Unnamed: 0
int64 0
160k
| title
stringlengths 3
1.06k
⌀ | abstract
stringlengths 3
122k
⌀ |
|---|---|---|
3,500 | Benefits and Inputs From Lactic Acid Bacteria and Their Bacteriocins as Alternatives to Antibiotic Growth Promoters During Food-Animal Production | Resistance to antibiotics is escalating and threatening humans and animals worldwide. Different countries have legislated or promoted the ban of antibiotics as growth promoters in livestock and aquaculture to reduce this phenomenon. Therefore, to improve animal growth and reproduction performance and to control multiple bacterial infections, there is a potential to use probiotics as non-antibiotic growth promoters. Lactic acid bacteria (LAB) offer various advantages as potential probiotics and can be considered as alternatives to antibiotics during food-animal production. LAB are safe microorganisms with abilities to produce different inhibitory compounds such as bacteriocins, organic acids as lactic acid, hydrogen peroxide, diacetyl, and carbon dioxide. LAB can inhibit harmful microorganisms with their arsenal, or through competitive exclusion mechanism based on competition for binding sites and nutrients. LAB endowed with specific enzymatic functions (amylase, protease…) can improve nutrients acquisition as well as animal immune system stimulation. This review aimed at underlining the benefits and inputs from LAB as potential alternatives to antibiotics in poultry, pigs, ruminants, and aquaculture production. |
3,501 | Using noninvasive metagenomics to characterize viral communities from wildlife | Microbial communities play an important role in organismal and ecosystem health. While high‐throughput metabarcoding has revolutionized the study of bacterial communities, generating comparable viral communities has proven elusive, particularly in wildlife samples where the diversity of viruses and limited quantities of viral nucleic acid present distinctive challenges. Metagenomic sequencing is a promising solution for studying viral communities, but the lack of standardized methods currently precludes comparisons across host taxa or localities. Here, we developed an untargeted shotgun metagenomic sequencing protocol to generate comparable viral communities from noninvasively collected faecal and oropharyngeal swabs. Using samples from common vampire bats (Desmodus rotundus), a key species for virus transmission to humans and domestic animals, we tested how different storage media, nucleic acid extraction procedures and enrichment steps affect viral community detection. Based on finding viral contamination in foetal bovine serum, we recommend storing swabs in RNAlater or another nonbiological medium. We recommend extracting nucleic acid directly from swabs rather than from supernatant or pelleted material, which had undetectable levels of viral RNA. Results from a low‐input RNA library preparation protocol suggest that ribosomal RNA depletion and light DNase treatment reduce host and bacterial nucleic acid, and improve virus detection. Finally, applying our approach to twelve pooled samples from seven localities in Peru, we showed that detected viral communities saturated at the attained sequencing depth, allowing unbiased comparisons of viral community composition. Future studies using the methods outlined here will elucidate the determinants of viral communities across host species, environments and time. |
3,502 | A decision-support framework to optimize border control for global outbreak mitigation | The introduction and spread of emerging infectious diseases is increasing in both prevalence and scale. Whether naturally, accidentally or maliciously introduced, the substantial uncertainty surrounding the emergence of novel viruses, specifically where they may come from and how they will spread, demands robust and quantifiably validated outbreak control policies that can be implemented in real time. This work presents a novel mathematical modeling framework that integrates both outbreak dynamics and outbreak control into a decision support tool for mitigating infectious disease pandemics that spread through passenger air travel. An ensemble of border control strategies that exploit properties of the air traffic network structure and expected outbreak behavior are proposed. A stochastic metapopulation epidemic model is developed to evaluate and rank the control strategies based on their effectiveness in reducing the spread of outbreaks. Sensitivity analyses are conducted to illustrate the robustness of the proposed control strategies across a range of outbreak scenarios, and a case study is presented for the 2009 H1N1 influenza pandemic. This study highlights the importance of strategically allocating outbreak control resources, and the results can be used to identify the most robust border control policy that can be implemented in the early stages of an outbreak. |
3,503 | Invasive and non-invasive diagnostic approaches for microbiological diagnosis of hospital-acquired pneumonia | BACKGROUND: Data on the methods used for microbiological diagnosis of hospital-acquired pneumonia (HAP) are mainly extrapolated from ventilator-associated pneumonia. HAP poses additional challenges for respiratory sampling, and the utility of sputum or distal sampling in HAP has not been comprehensively evaluated, particularly in HAP admitted to the ICU. METHODS: We analyzed 200 patients with HAP from six ICUs in a teaching hospital in Barcelona, Spain. The respiratory sampling methods used were divided into non-invasive [sputum and endotracheal aspirate (EAT)] and invasive [fiberoptic-bronchoscopy aspirate (FBAS), and bronchoalveolar lavage (BAL)]. RESULTS: A median of three diagnostic methods were applied [range 2–4]. At least one respiratory sampling method was applied in 93% of patients, and two or more were applied in 40%. Microbiological diagnosis was achieved in 99 (50%) patients, 69 (70%) by only one method (42% FBAS, 23% EAT, 15% sputum, 9% BAL, 7% blood culture, and 4% urinary antigen). Seventy-eight (39%) patients underwent a fiberoptic-bronchoscopy when not receiving mechanical ventilation. Higher rates of microbiological diagnosis were observed in the invasive group (56 vs. 39%, p = 0.018). Patients with microbiological diagnosis more frequently presented changes in their empirical antibiotic scheme, mainly de-escalation. CONCLUSIONS: A comprehensive approach might be undertaken for microbiological diagnosis in critically ill nonventilated HAP. Sputum sampling determined one third of microbiological diagnosis in HAP patients who were not subsequently intubated. Invasive methods were associated with higher rates of microbiological diagnosis. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13054-019-2348-2) contains supplementary material, which is available to authorized users. |
3,504 | The origins of the great pandemic | The timing and location of the first cases of the 1918 influenza pandemic are still controversial, a century after the pandemic became widely recognized. Here, we critically review competing hypotheses on the timing and geographical origin of this important outbreak and provide new historical insights into debates within military circles as to the nature of putative pre-1918 influenza activity. We also synthesize current knowledge about why the 1918 pandemic was so intense in young adults. Although it is still not clear precisely when and where the outbreak began and symptom-based reports are unlikely to reveal the answer, indirect methods including phylogenetics provide important clues, and we consider whether intense influenza activity as far back as 1915 in the USA may have been caused by viral strains closely related to the 1918 one. |
3,505 | Viral infection detection using metagenomics technology in six poultry farms of eastern China | With rapidly increasing animal pathogen surveillance requirements, new technologies are needed for a comprehensive understanding of the roles of pathogens in the occurrence and development of animal diseases. We applied metagenomic technology to avian virus surveillance to study the main viruses infecting six poultry farms in two provinces in eastern China. Cloacal/throat double swabs were collected from 60 birds at each farm according to a random sampling method. The results showed that the method could simultaneously detect major viruses infecting farms, including avian influenza virus, infectious bronchitis virus, Newcastle disease virus, rotavirus G, duck hepatitis B virus, and avian leukemia virus subgroup J in several farms. The test results were consistent with the results from traditional polymerase chain reaction (PCR) or reverse transcription-PCR analyses. Five H9N2 and one H3N8 avian influenza viruses were detected at the farms and were identified as low pathogenic avian influenza viruses according to HA cleavage sites analysis. One detected Newcastle disease virus was classified as Class II genotype I and avirulent type according to F0 cleavage sites analysis. Three avian infectious bronchitis viruses were identified as 4/91, CK/CH/LSC/99I and TC07-2 genotypes by phylogenetic analysis of S1 genes. The viral infection surveillance method using metagenomics technology enables the monitoring of multiple viral infections, which allows the detection of main infectious viruses. |
3,506 | Experimental Zika virus infection of Jamaican fruit bats (Artibeus jamaicensis) and possible entry of virus into brain via activated microglial cells | The emergence of Zika virus (ZIKV) in the New World has led to more than 200,000 human infections. Perinatal infection can cause severe neurological complications, including fetal and neonatal microcephaly, and in adults there is an association with Guillain-Barré syndrome (GBS). ZIKV is transmitted to humans by Aedes sp. mosquitoes, yet little is known about its enzootic cycle in which transmission is thought to occur between arboreal Aedes sp. mosquitos and non-human primates. In the 1950s and ‘60s, several bat species were shown to be naturally and experimentally susceptible to ZIKV with acute viremia and seroconversion, and some developed neurological disease with viral antigen detected in the brain. Because of ZIKV emergence in the Americas, we sought to determine susceptibility of Jamaican fruit bats (Artibeus jamaicensis), one of the most common bats in the New World. Bats were inoculated with ZIKV PRVABC59 but did not show signs of disease. Bats held to 28 days post-inoculation (PI) had detectable antibody by ELISA and viral RNA was detected by qRT-PCR in the brain, saliva and urine in some of the bats. Immunoreactivity using polyclonal anti-ZIKV antibody was detected in testes, brain, lung and salivary glands plus scrotal skin. Tropism for mononuclear cells, including macrophages/microglia and fibroblasts, was seen in the aforementioned organs in addition to testicular Leydig cells. The virus likely localized to the brain via infection of Iba1(+) macrophage/microglial cells. Jamaican fruit bats, therefore, may be a useful animal model for the study of ZIKV infection. This work also raises the possibility that bats may have a role in Zika virus ecology in endemic regions, and that ZIKV may pose a wildlife disease threat to bat populations. |
3,507 | Modeling the impact of quarantine during an outbreak of Ebola virus disease | The quarantine of people suspected of being exposed to an infectious agent is one of the most basic public health measure that has historically been used to combat the spread of communicable diseases in human communities. This study presents a new deterministic model for assessing the population-level impact of the quarantine of individuals suspected of being exposed to disease on the spread of the 2014–2015 outbreaks of Ebola viral disease. It is assumed that quarantine is imperfect (i.e., individuals can acquire infection during quarantine). In the absence of quarantine, the model is shown to exhibit global dynamics with respect to the disease-free and its unique endemic equilibrium when a certain epidemiological threshold (denoted by [Formula: see text]) is either less than or greater than unity. Thus, unlike the full model with imperfect quarantine (which is known to exhibit the phenomenon of backward bifurcation), the version of the model with no quarantine does not undergo a backward bifurcation. Using data relevant to the 2014–2015 Ebola transmission dynamics in the three West African countries (Guinea, Liberia and Sierra Leone), uncertainty analysis of the model show that, although the current level and effectiveness of quarantine can lead to significant reduction in disease burden, they fail to bring the associated quarantine reproduction number ([Formula: see text]) to a value less than unity (which is needed to make effective disease control or elimination feasible). This reduction of [Formula: see text] is, however, very possible with a modest increase in quarantine rate and effectiveness. It is further shown, via sensitivity analysis, that the parameters related to the effectiveness of quarantine (namely the parameter associated with the reduction in infectiousness of infected quarantined individuals and the contact rate during quarantine) are the main drivers of the disease transmission dynamics. Overall, this study shows that the singular implementation of a quarantine intervention strategy can lead to the effective control or elimination of Ebola viral disease in a community if its coverage and effectiveness levels are high enough. |
3,508 | Evaluation of the effectiveness of the SurePure Turbulator ultraviolet-C irradiation equipment on inactivation of different enveloped and non-enveloped viruses inoculated in commercially collected liquid animal plasma | The objective of this study was to evaluate the effectiveness of the SurePure Turbulator ultraviolet-C (UV-C, 254 nm wavelength) irradiation equipment on inactivation of different enveloped and non-enveloped viruses in commercially collected liquid animal plasma. Specifically, Pseudorabies virus (PRV), Porcine reproductive and respiratory syndrome virus (PRRSV), Porcine epidemic diarrhea virus (PEDV), Bovine viral diarrhea virus (BVDV), Classical swine fever virus (CSFV), Swine influenza virus (SIV) as enveloped viruses and Porcine parvovirus (PPV), Swine vesicular disease virus (SVDV), Porcine circovirus type 2 (PCV-2) and Senecavirus A (SVA) as non-enveloped viruses, were inoculated in bovine or porcine plasma and subjected to different UV-C irradiation doses (0, 750, 1500, 3000, 6000 and 9000 J/L) using an UV-C device developed for opaque liquid working under turbulent flow. The enveloped viruses tested were inactivated at < 3000 J/L of UV-C, being the dose needed to inactivate 4 log TCID(50) (4D) of 1612 J/L for PRV,1004 J/L for PRRSV, 1953 J/L for PEDV, 1639 J/L for SIV, 1641 J/L for CSFV and 1943 J/L for BVDV. The non-enveloped viruses tended to have higher 4D values: 2161 J/L for PPV, 3223 J/L for SVA and 3708 J/L for SVDV. Because the initial viral concentration was <4.0 Log for PCV-2, it was not possible to calculate the 4D value for this virus. In conclusion, these results demonstrated that the SurePure Turbulator UV-C treatment system is capable of inactivating significant levels of swine viruses inoculated in commercially collected porcine or bovine plasma. It was concluded that irradiation with UV-C can provide an additional redundant biosafety feature in the manufacturing process of spray-dried animal plasma. |
3,509 | Octa-repeat domain of the mammalian prion protein mRNA forms stable A-helical hairpin structure rather than G-quadruplexes | Misfolding and aggregation of prion protein (PrP) causes neurodegenerative diseases like Creutzfeldt-Jakob disease (CJD) and scrapie. Besides the consensus that spontaneous conversion of normal cellular PrP(C) into misfolded and aggregating PrP(Sc) is the central event in prion disease, an alternative hypothesis suggests the generation of pathological PrP(Sc) by rare translational frameshifting events in the octa-repeat domain of the PrP mRNA. Ribosomal frameshifting most commonly relies on a slippery site and an adjacent stable RNA structure to stall translating ribosome. Hence, it is crucial to unravel the secondary structure of the octa-repeat domain of PrP mRNA. Each of the five octa-repeats contains a motif (GGCGGUGGUGGCUGGG) which alone in vitro forms a G-quadruplex. Since the propensity of mRNA to form secondary structure depends on the sequence context, we set to determine the structure of the complete octa-repeat region. We assessed the structure of full-length octa-repeat domain of PrP mRNA using dynamic light scattering (DLS), small angle X-ray scattering (SAXS), circular dichroism (CD) spectroscopy and selective 2′-hydroxyl acylation analysis by primer extension (SHAPE). Our data show that the PrP octa-repeat mRNA forms stable A-helical hairpins with no evidence of G-quadruplex structure even in the presence of G-quadruplex stabilizing agents. |
3,510 | Estimation of the effective reproduction number of influenza based on weekly reports in Miyazaki Prefecture | In Japan, as part of surveillance for seasonal influenza, the number of patients per influenza sentinel site is counted on a weekly basis. Currently, reference values are set for the weekly reported number of influenza cases per sentinel, and pre-epidemic and epidemic warnings are issued based on these values. In this study, we examined the association between these reference values and the effective reproduction number (R(t)) using surveillance data for Miyazaki Prefecture collected from 2010 to 2011. There are nine public health centre jurisdictions in this prefecture, and R(t) exceeded 1.0 at the time when pre-epidemic warnings were issued in almost all the jurisdictions. Thus, it was indicated that the validity of the reference value was also high for influenza transmission. However, our results indicated the presence of secondary epidemic caused by infections originating both from other jurisdictions and inner jurisdictions, and it is occasionally not possible to evaluate the end of an epidemic in a jurisdiction using only the reference value of termination. It is necessary to establish new methods after considering the situation in the surrounding jurisdictions for more detailed epidemic predictions. |
3,511 | Mapping novel genetic loci associated with female liver weight variations using Collaborative Cross mice | BACKGROUND: Liver weight is a complex trait, controlled by polygenic factors and differs within populations. Dissecting the genetic architecture underlying these variations will facilitate the search for key role candidate genes involved directly in the hepatomegaly process and indirectly involved in related diseases etiology. METHODS: Liver weight of 506 mice generated from 39 different Collaborative Cross (CC) lines with both sexes at age 20 weeks old was determined using an electronic balance. Genomic DNA of the CC lines was genotyped with high‐density single nucleotide polymorphic markers. RESULTS: Statistical analysis revealed a significant (P < 0.05) variation of liver weight between the CC lines, with broad sense heritability (H (2)) of 0.32 and genetic coefficient of variation (CV(G)) of 0.28. Subsequently, quantitative trait locus (QTL) mapping was performed, and results showed a significant QTL only for females on chromosome 8 at genomic interval 88.61‐93.38 Mb (4.77 Mb). Three suggestive QTL were mapped at chromosomes 4, 12 and 13. The four QTL were designated as LWL1‐LWL4 referring to liver weight loci 1‐4 on chromosomes 8, 4, 12 and 13, respectively. CONCLUSION: To our knowledge, this report presents, for the first time, the utilization of the CC for mapping QTL associated with baseline liver weight in mice. Our findings demonstrate that liver weight is a complex trait controlled by multiple genetic factors that differ significantly between sexes. |
3,512 | Respiratory mechanics in infants with severe bronchiolitis on controlled mechanical ventilation | BACKGROUND: Analysis of respiratory mechanics during mechanical ventilation (MV) is able to estimate resistive, elastic and inertial components of the working pressure of the respiratory system. Our aim was to discriminate the components of the working pressure of the respiratory system in infants on MV with severe bronchiolitis admitted to two PICU’s. METHODS: Infants younger than 1 year old with acute respiratory failure caused by severe bronchiolitis underwent neuromuscular blockade, tracheal intubation and volume controlled MV. Shortly after intubation studies of pulmonary mechanics were performed using inspiratory and expiratory breath hold. The maximum inspiratory and expiratory flow (QI and QE) as well as peak inspiratory (PIP), plateau (PPL) and total expiratory pressures (tPEEP) were measured. Inspiratory and expiratory resistances (RawI and RawE) and Time Constants (K(TI) and K(TE)) were calculated. RESULTS: We included 16 patients, of median age 2.5 (1–5.8) months. Bronchiolitis due to respiratory syncytial virus was the main etiology (93.8%) and 31.3% had comorbidities. Measured respiratory pressures were PIP 29 (26–31), PPL 24 (20–26), tPEEP 9 [8–11] cmH2O. Elastic component of the working pressure was significantly higher than resistive and both higher than threshold (tPEEP – PEEP) (P < 0.01). QI was significantly lower than QE [5 (4.27–6.75) v/s 16.5 (12–23.8) L/min. RawI and RawE were 38.8 (32–53) and 40.5 (22–55) cmH2O/L/s; K(TI) and K(TE) [0.18 (0.12–0.30) v/s 0.18 (0.13–0.22) s], and K(TI):K(TE) ratio was 1:1.04 (1:0.59–1.42). CONCLUSIONS: Analysis of respiratory mechanics of infants with severe bronchiolitis receiving MV shows that the elastic component of the working pressure of the respiratory system is the most important. The elastic and resistive components in conjunction with flow profile are characteristic of restrictive diseases. A better understanding of lung mechanics in this group of patients may lead to change the traditional ventilatory approach to severe bronchiolitis. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12890-017-0475-6) contains supplementary material, which is available to authorized users. |
3,513 | Transient plant production of Salmonella Typhimurium diagnostic antibodies | Salmonella Typhimurium is one of the most important zoonotic pathogens worldwide and a major cause of economic losses in the pig production chain. The emergence of multi-drug resistant strains over the past years has led to considerations about an enhanced surveillance of bacterial food contamination. Currently, ELISA is the method of choice for high throughput identification of S. Typhimurium. The sensitivity and specificity of this assay might be improved by application of new diagnostic antibodies. We focused on plant-based expression of candidate diagnostic TM43-E10 antibodies discovered using as antigen the S. Typhimurium OmpD protein. The scFv-TM43-E10 and scFv-Fc-TM43-E10 antibody derivatives have been successfully produced in N. benthamiana using a deconstructed movement-deficient PVX vector supplemented with the γb silencing suppressor from Poa semilatent virus. The plant-made antibodies showed the same antigen-binding specificity as that of the microbial/mammalian cell-produced counterparts and could recognize the OmpD antigen in S. Typhimurium infected plant samples. |
3,514 | Quantitative impacts of incubation phase transmission of foot-and-mouth disease virus | The current investigation applied a Bayesian modeling approach to a unique experimental transmission study to estimate the occurrence of transmission of foot-and-mouth disease (FMD) during the incubation phase amongst group-housed pigs. The primary outcome was that transmission occurred approximately one day prior to development of visible signs of disease (posterior median 21 hours, 95% CI: 1.1–45.0). Updated disease state durations were incorporated into a simulation model to examine the importance of addressing preclinical transmission in the face of robust response measures. Simulation of FMD outbreaks in the US pig production sector demonstrated that including a preclinical infectious period of one day would result in a 40% increase in the median number of farms affected (166 additional farms and 664,912 pigs euthanized) compared to the scenario of no preclinical transmission, assuming suboptimal outbreak response. These findings emphasize the importance of considering transmission of FMD during the incubation phase in modeling and response planning. |
3,515 | Early and dynamic alterations of Th2/Th1 in previously immunocompetent patients with community-acquired severe sepsis: a prospective observational study | BACKGROUND: T helper (Th) cells regulate sepsis processes, including primary pathogen clear and secondary pathogen defence. The objectives of this study were to determine the early and dynamic alterations of Th1 and Th2 populations to community-acquired severe sepsis upon onset among previously immunocompetent patients and whether it was related to clinical outcomes. METHODS: This prospective observational cohort study was conducted at a general intensive care unit (ICU) of a tertiary teaching hospital in China. Immunocompetent patients with community-acquired severe sepsis within 24 h upon onset were included as septic group. Healthy volunteers and critically ill patients without severe sepsis were recruited as controls. Whole blood was collected on D0, 3rd day (D3) and 7th day (D7) for septic group and once upon enrollment for controls. Th1 and Th2 populations were measured by flow cytometry and assessed for associations with 28-day mortality using cox proportional hazard models. Associations of dynamic alterations of Th cell subpopulations with clinical outcomes were investigated. RESULTS: This study demonstrated that community-acquired severe sepsis patients (n = 71) had increased Th2/Th1 and Th2 populations, compared to healthy controls (n = 7) and critically ill patients without severe sepsis (n = 7) at admission. Among the septic cohort, values of Th2/Th1 were significantly higher in non-survivors than survivors on D0 (p = 0.04), D3 (p < 0.001) and D7 (p < 0.001). Patients with persistently increasing Th2/Th1 demonstrated the highest mortality (47.1%) and incidence of ICU-acquired infections (64.7%). CONCLUSIONS: Th2/Th1 was markedly up-regulated with Th2 dominance upon community-acquired severe sepsis onset among previously immunocompetent patients and its persistently dynamic increase was associated with ICU-acquired infections and 28-day death. Trial registration Institutional Ethics Committee of Zhongda Hospital, 2014ZDSYLL086, registered in June 2014-prospectively registered; ClinicalTrials.gov, NCT02883218, registered on 25 Aug 2016-retrospectively registered, https://www.clinicaltrials.gov/ct2/show/NCT02883218?cond=NCT02883218&rank=1 ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12967-019-1811-9) contains supplementary material, which is available to authorized users. |
3,516 | Key Gaps in the Knowledge of the Porcine Respiratory Reproductive Syndrome Virus (PRRSV) | The porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important swine diseases in the world. It is causing an enormous economic burden due to reproductive failure in sows and a complex respiratory syndrome in pigs of all ages, with mortality varying from 2 to 100% in the most extreme cases of emergent highly pathogenic strains. PRRSV displays complex interactions with the immune system and a high mutation rate, making the development, and implementation of control strategies a major challenge. In this review, the biology of the virus will be addressed focusing on newly discovered functions of non-structural proteins and novel dissemination mechanisms. Secondly, the role of different cell types and viral proteins will be reviewed in natural and vaccine-induced immune response together with the role of different immune evasion mechanisms focusing on those gaps of knowledge that are critical to generate more efficacious vaccines. Finally, novel strategies for antigen discovery and vaccine development will be discussed, in particular the use of exosomes (extracellular vesicles of endocytic origin). As nanocarriers of lipids, proteins and nucleic acids, exosomes have potential effects on cell activation, modulation of immune responses and antigen presentation. Thus, representing a novel vaccination approach against this devastating disease. |
3,517 | Counteraction of HCV-Induced Oxidative Stress Concurs to Establish Chronic Infection in Liver Cell Cultures | Hepatitis C virus (HCV) is a blood-borne pathogen causing acute and chronic hepatitis. A significant number of people chronically infected with HCV develop cirrhosis and/or liver cancer. The pathophysiologic mechanisms of hepatocyte damage associated with chronic HCV infection are not fully understood yet, mainly due to the lack of an in vitro system able to recapitulate the stages of infection in vivo. Several studies underline that HCV virus replication depends on redox-sensitive cellular pathways; in addition, it is known that virus itself induces alterations of the cellular redox state. However, the exact interplay between HCV replication and oxidative stress has not been elucidated. In particular, the role of reduced glutathione (GSH) in HCV replication and infection is still not clear. We set up an in vitro system, based on low m.o.i. of Huh7.5 cell line with a HCV infectious clone (J6/JFH1), that reproduced the acute and persistent phases of HCV infection up to 76 days of culture. We demonstrated that the acute phase of HCV infection is characterized by the elevated levels of reactive oxygen species (ROS) associated in part with an increase of NADPH-oxidase transcripts and activity and a depletion of GSH accompanied by high rates of viral replication and apoptotic cell death. Conversely, the chronic phase is characterized by a reestablishment of reduced environment due to a decreased ROS production and increased GSH content in infected cells that might concur to the establishment of viral persistence. Treatment with the prooxidant auranofin of the persistently infected cultures induced the increase of viral RNA titer, suggesting that a prooxidant state could favor the reactivation of HCV viral replication that in turn caused cell damage and death. Our results suggest that targeting the redox-sensitive host-cells pathways essential for viral replication and/or persistence may represent a promising option for contrasting HCV infection. |
3,518 | Antibiotic misuse in respiratory tract infections in children and adults—a prospective, multicentre study (TAILORED Treatment) | Respiratory tract infections (RTI) are more commonly caused by viral pathogens in children than in adults. Surprisingly, little is known about antibiotic use in children as compared to adults with RTI. This prospective study aimed to determine antibiotic misuse in children and adults with RTI, using an expert panel reference standard, in order to prioritise the target age population for antibiotic stewardship interventions. We recruited children and adults who presented at the emergency department or were hospitalised with clinical presentation of RTI in The Netherlands and Israel. A panel of three experienced physicians adjudicated a reference standard diagnosis (i.e. bacterial or viral infection) for all the patients using all available clinical and laboratory information, including a 28-day follow-up assessment. The cohort included 284 children and 232 adults with RTI (median age, 1.3 years and 64.5 years, respectively). The proportion of viral infections was larger in children than in adults (209(74%) versus 89(38%), p < 0.001). In case of viral RTI, antibiotics were prescribed (i.e. overuse) less frequently in children than in adults (77/209 (37%) versus 74/89 (83%), p < 0.001). One (1%) child and three (2%) adults with bacterial infection were not treated with antibiotics (i.e. underuse); all were mild cases. This international, prospective study confirms major antibiotic overuse in patients with RTI. Viral infection is more common in children, but antibiotic overuse is more frequent in adults with viral RTI. Together, these findings support the need for effective interventions to decrease antibiotic overuse in RTI patients of all ages. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10096-018-03454-2) contains supplementary material, which is available to authorized users. |
3,519 | Schmallenberg virus induces apoptosis in Vero cell line via extrinsic and intrinsic pathways in a time and dose dependent manner | Schmallenberg virus (SBV), discovered in 2011 in Germany, is associated with clinical manifestations of fever, diarrhea, reduced milk yield, abortions and congenital malformations in ruminants. Despite many studies performed for SBV, there is no detailed research on in vitro apoptotic effect of SBV. This study is aimed to determine apoptosis pathways and role of pro-apoptotic and anti-apoptotic molecules in Vero cells infected with SBV. The study results showed that SBV induced apoptosis via both extrinsic and intrinsic pathways by activating both caspase-8 and caspase-9, respectively. Expression analyses of pro-apoptotic (Bax, Bak and Puma) and anti-apoptotic (Bcl-2 and Bcl-XL) genes revealed that SBV-induced apoptosis causes upregulation of pro-apoptotic genes, dominantly via Puma gene, whereas Bcl-2 and Bcl-XL genes were downregulated. In conclusion, this is the first detailed report about SBV induced apoptosis in the Vero cells via both extrinsic and intrinsic cascades and apoptosis induction is seem to be regulated by Puma. |
3,520 | Adenovirus flow in host cell networks | Viruses are obligatory parasites that take advantage of intracellular niches to replicate. During infection, their genomes are carried in capsids across the membranes of host cells to sites of virion production by exploiting cellular behaviour and resources to guide and achieve all aspects of delivery and the downstream virus manufacturing process. Successful entry hinges on execution of a precisely tuned viral uncoating program where incoming capsids disassemble in consecutive steps to ensure that genomes are released at the right time, and in the right place for replication to occur. Each step of disassembly is cell-assisted, involving individual pathways that transmit signals to regulate discrete functions, but at the same time, these signalling pathways are organized into larger networks, which communicate back and forth in complex ways in response to the presence of virus. In this review, we consider the elegant strategy by which adenoviruses (AdVs) target and navigate cellular networks to initiate the production of progeny virions. There are many remarkable aspects about the AdV entry program; for example, the virus gains targeted control of a large well-defined local network neighbourhood by coupling several interacting processes (including endocytosis, autophagy and microtubule trafficking) around a collective reference state centred on the interactional topology and multifunctional nature of protein VI. Understanding the network targeting activity of protein VI, as well as other built-in mechanisms that allow AdV particles to be efficient at navigating the subsystems of the cell, can be used to improve viral vectors, but also has potential to be incorporated for use in entirely novel delivery systems. |
3,521 | IFITM proteins drive type 2 T helper cell differentiation and exacerbate allergic airway inflammation | The interferon‐inducible transmembrane (Ifitm/Fragilis) genes encode homologous proteins that are induced by IFNs. Here, we show that IFITM proteins regulate murine CD4(+) Th cell differentiation. Ifitm2 and Ifitm3 are expressed in wild‐type (WT) CD4(+) T cells. On activation, Ifitm3 was downregulated and Ifitm2 was upregulated. Resting Ifitm‐family‐deficient CD4(+) T cells had higher expression of Th1‐associated genes than WT and purified naive Ifitm‐family‐deficient CD4(+) T cells differentiated more efficiently to Th1, whereas Th2 differentiation was inhibited. Ifitm‐family‐deficient mice, but not Ifitm3‐deficient mice, were less susceptible than WT to induction of allergic airways disease, with a weaker Th2 response and less severe disease and lower Il4 but higher Ifng expression and IL‐27 secretion. Thus, the Ifitm family is important in adaptive immunity, influencing Th1/Th2 polarization, and Th2 immunopathology. |
3,522 | A system for production of defective interfering particles in the absence of infectious influenza A virus | Influenza A virus (IAV) infection poses a serious health threat and novel antiviral strategies are needed. Defective interfering particles (DIPs) can be generated in IAV infected cells due to errors of the viral polymerase and may suppress spread of wild type (wt) virus. The antiviral activity of DIPs is exerted by a DI genomic RNA segment that usually contains a large deletion and suppresses amplification of wt segments, potentially by competing for cellular and viral resources. DI-244 is a naturally occurring prototypic segment 1-derived DI RNA in which most of the PB2 open reading frame has been deleted and which is currently developed for antiviral therapy. At present, coinfection with wt virus is required for production of DI-244 particles which raises concerns regarding biosafety and may complicate interpretation of research results. Here, we show that cocultures of 293T and MDCK cell lines stably expressing codon optimized PB2 allow production of DI-244 particles solely from plasmids and in the absence of helper virus. Moreover, we demonstrate that infectivity of these particles can be quantified using MDCK-PB2 cells. Finally, we report that the DI-244 particles produced in this novel system exert potent antiviral activity against H1N1 and H3N2 IAV but not against the unrelated vesicular stomatitis virus. This is the first report of DIP production in the absence of infectious IAV and may spur efforts to develop DIPs for antiviral therapy. |
3,523 | Effectiveness of Integrative Therapy for Parkinson’s Disease Management | Objectives: To investigate the effectiveness of integrative therapy on prevalence and length of hospitalization and management of major complications of Parkinson’s disease (PD) in the South Korea. Methods: This study was a retrospective cohort analysis conducted using the National Health Insurance Service-National Sample Cohort in the South Korea. Patients over 65 years old who were newly diagnosed with PD during 2007–2011 were identified. The integrative therapy group was defined as patients treated with both Korean medicine (KM) and biomedicine, and the monotherapy group consisted of patients treated with biomedicine alone. From PD diagnosis to 2013, the prevalence and annual length of hospitalization because of PD and major complications (dementia, depression and pneumonia/sepsis) were analyzed using logistic regression, ANOVA and t-tests after propensity score (PS) matching with a 1:1 ratio. Results: After PS estimation and matching, the cohort used in the analysis included 228 subjects (114 integrative therapy group, 114 monotherapy group). Sex, age, index year, comorbidity, severity of disability, neurologic care, and anti-parkinsonism medication (levodopa, ropinirole, pramipexole, selegiline) were adjusted in both groups. The prevalence of hospitalization due to pneumonia/sepsis was 0.50 times (95% C.I.: 0.26–0.96) lower in the integrative therapy group than the monotherapy group, which was statistically significant (p = 0.038). The prevalence and annual length of total hospitalization and hospitalization because of PD, dementia, and depression in the integrative therapy group showed positive results compared to the monotherapy group, but these differences were not statistically significant. Conclusion: It has not been clearly identified that integrative therapy with KM and biomedicine for PD management is better treatment for patients compared to biomedicine monotherapy; however, we found a clue of better result in integrated therapy. Therefore, further investigation by increasing the number of subjects is needed to confirm the findings presented herein. |
3,524 | Identification and genetic characterization of a novel Orthobunyavirus species by a straightforward high-throughput sequencing-based approach | Identification and characterization of novel unknown viruses is of great importance. The introduction of high-throughput sequencing (HTS)-based methods has paved the way for genomics-based detection of pathogens without any prior assumptions about the characteristics of the organisms. However, the use of HTS for the characterization of viral pathogens from clinical samples remains limited. Here, we report the identification of a novel Orthobunyavirus species isolated from horse plasma. The identification was based on a straightforward HTS approach. Following enrichment in cell culture, RNA was extracted from the growth medium and rapid library preparation, HTS and primary bioinformatic analyses were performed in less than 12 hours. Taxonomical profiling of the sequencing reads did not reveal sequence similarities to any known virus. Subsequent application of de novo assembly tools to the sequencing reads produced contigs, of which three showed some similarity to the L, M, and S segments of viruses belonging to the Orthobunyavirus genus. Further refinement of these contigs resulted in high-quality, full-length genomic sequences of the three genomic segments (L, M and S) of a novel Orthobunyavirus. Characterization of the genomic sequence, including the prediction of open reading frames and the inspection of consensus genomic termini and phylogenetic analysis, further confirmed that the novel virus is indeed a new species, which we named Ness Ziona virus. |
3,525 | Genetic control of the mouse HDL proteome defines HDL traits, function, and heterogeneity | HDLs are nanoparticles with more than 80 associated proteins, phospholipids, cholesterol, and cholesteryl esters. The potential inverse relation of HDL to coronary artery disease (CAD) and the effects of HDL on myriad other inflammatory conditions warrant a better understanding of the genetic basis of the HDL proteome. We conducted a comprehensive genetic analysis of the regulation of the proteome of HDL isolated from a panel of 100 diverse inbred strains of mice (the hybrid mouse diversity panel) and examined protein composition and efflux capacity to identify novel factors that affect the HDL proteome. Genetic analysis revealed widely varied HDL protein levels across the strains. Some of this variation was explained by local cis-acting regulation, termed cis-protein quantitative trait loci (QTLs). Variations in apoA-II and apoC-3 affected the abundance of multiple HDL proteins, indicating a coordinated regulation. We identified modules of covarying proteins and defined a protein-protein interaction network that describes the protein composition of the naturally occurring subspecies of HDL in mice. Sterol efflux capacity varied up to 3-fold across the strains, and HDL proteins displayed distinct correlation patterns with macrophage and ABCA1-specific cholesterol efflux capacity and cholesterol exchange, suggesting that subspecies of HDL participate in discrete functions. The baseline and stimulated sterol efflux capacity phenotypes were associated with distinct QTLs with smaller effect size, suggesting a multigenetic regulation. Our results highlight the complexity of HDL particles by revealing the high degree of heterogeneity and intercorrelation, some of which is associated with functional variation, and support the concept that HDL-cholesterol alone is not an accurate measure of HDL’s properties, such as protection against CAD. |
3,526 | Consequences of delays and imperfect implementation of isolation in epidemic control | For centuries isolation has been the main control strategy of unforeseen epidemic outbreaks. When implemented in full and without delay, isolation is very effective. However, flawless implementation is seldom feasible in practice. We present an epidemic model called SIQ with an isolation protocol, focusing on the consequences of delays and incomplete identification of infected hosts. The continuum limit of this model is a system of Delay Differential Equations, the analysis of which reveals clearly the dependence of epidemic evolution on model parameters including disease reproductive number, isolation probability, speed of identification of infected hosts and recovery rates. Our model offers estimates on minimum response capabilities needed to curb outbreaks, and predictions of endemic states when containment fails. Critical response capability is expressed explicitly in terms of parameters that are easy to obtain, to assist in the evaluation of funding priorities involving preparedness and epidemics management. |
3,527 | Phylogeographic investigation of 2014 porcine epidemic diarrhea virus (PEDV) transmission in Taiwan | The porcine epidemic diarrhea virus (PEDV) that emerged and spread throughout Taiwan in 2014 triggered significant concern in the country’s swine industry. Acknowledging the absence of a thorough investigation at the geographic level, we used 2014 outbreak sequence information from the Taiwan government’s open access databases plus GenBank records to analyze PEDV dissemination among Taiwanese pig farms. Genetic sequences, locations, and dates of identified PEDV-positive cases were used to assess spatial, temporal, clustering, GIS, and phylogeographic factors affecting PEDV dissemination. Our conclusion is that S gene sequences from 2014 PEDV-positive clinical samples collected in Taiwan were part of the same Genogroup 2 identified in the US in 2013. According to phylogenetic and phylogeographic data, viral strains collected in different areas were generally independent of each other, with certain clusters identified across different communities. Data from GIS and multiple potential infection factors were used to pinpoint cluster dissemination in areas with large numbers of swine farms in southern Taiwan. The data indicate that the 2014 Taiwan PEDV epidemic resulted from the spread of multiple strains, with strong correlations identified with pig farm numbers and sizes (measured as animal concentrations), feed mill numbers, and the number of slaughterhouses in a specifically defined geographic area. |
3,528 | Bacillus Calmette-Guérin Induces PD-L1 Expression on Antigen-Presenting Cells via Autocrine and Paracrine Interleukin-STAT3 Circuits | Bacillus Calmette-Guérin (BCG) is the only licensed vaccine for tuberculosis (TB), and is also used as an immunotherapy for bladder cancer and other malignancies due to its immunostimulatory properties. Mycobacteria spp., however, are well known for their numerous immune evasion mechanisms that limit the true potential of their therapeutic use. One such major mechanism is the induction of programmed death ligand-1 (PD-L1), which mitigates adaptive immune responses. Here, we sought to unravel the molecular pathways behind PD-L1 up-regulation on antigen-presenting cells (APCs) by BCG. We found that infection of APCs with BCG induced PD-L1 up-regulation, but that this did not depend on direct infection, suggesting a soluble mediator for this effect. BCG induced potent quantities of IL-6 and IL-10, and the downstream transcription factor STAT3 was hyper-phosphorylated. Intracellular analyses revealed that levels of PD-L1 molecules were associated with the STAT3 phosphorylation state, suggesting a causal link. Neutralisation of the IL-6 or IL-10 cytokine receptors dampened STAT3 phosphorylation and BCG-mediated up-regulation of PD-L1 on APCs. Pharmacological inhibition of STAT3 achieved the same effect, confirming an autocrine-paracrine cytokine loop as a mechanism for BCG-mediated up-regulation of PD-L1. Finally, an in vivo immunisation model showed that BCG vaccination under PD-L1 blockade could enhance antigen-specific memory CD4 T-cell responses. These novel findings could lead to refinement of BCG as both a vaccine for infectious disease and as a cancer immunotherapy. |
3,529 | A colorimetric strategy based on dynamic chemistry for direct detection of Trypanosomatid species | Leishmaniasis and Chagas disease are endemic in many countries, and re-emerging in the developed countries. A rapid and accurate diagnosis is important for early treatment for reducing the duration of infection as well as for preventing further potential health complications. In this work, we have developed a novel colorimetric molecular assay that integrates nucleic acid analysis by dynamic chemistry (ChemNAT) with reverse dot-blot hybridization in an array format for a rapid and easy discrimination of Leishmania major and Trypanosoma cruzi. The assay consists of a singleplex PCR step that amplifies a highly homologous DNA sequence which encodes for the RNA component of the large ribosome subunit. The amplicons of the two different parasites differ between them by single nucleotide variations, known as “Single Nucleotide Fingerprint” (SNF) markers. The SNF markers can be easily identified by naked eye using a novel micro Spin-Tube device "Spin-Tube", as each of them creates a specific spot pattern. Moreover, the direct use of ribosomal RNA without requiring the PCR pre-amplification step is also feasible, further increasing the simplicity of the assay. The molecular assay delivers sensitivity capable of identifying up to 8.7 copies per µL with single mismatch specificity. The Spin-Tube thus represents an innovative solution providing benefits in terms of time, cost, and simplicity, all of which are crucial for the diagnosis of infectious disease in developing countries. |
3,530 | A balanced game: chicken macrophage response to ALV-J infection | Avian leukosis virus subgroup J (ALV-J) infection can cause tumors and immunosuppression in infected chickens. Macrophages play a central role in host defense against invading pathogens. In this study, we discovered an interesting phenomenon: ALV-J replication is weakened from 3 hours post-infection (hpi) to 36 hpi, which was verified using Western blotting and RT-PCR. To further investigate the interaction between ALV-J and macrophages, transcriptome analysis was performed to analyze the host genes’ function in chicken primary monocyte-derived macrophages (MDM). Compared to the uninfected control, 624 up-regulated differentially expressed genes (DEG) and 341 down-regulated DEG at 3 hpi, and 174 up-regulated DEG and 87 down-regulated DEG at 36 hpi were identified in chicken MDM, respectively. ALV-J infection induced strong innate immune responses in chicken MDM at 3 hpi, instead of 36 hpi, according to the analysis results of Gene Ontology and KEGG pathway. Importantly, the host factors, such as up-regulated MIP-3α, IL-1β, iNOS, K60, IRG1, CH25H, NFKBIZ, lysozyme and OASL were involved in the host defense response during the course of ALV-J infection. On the contrary, up-regulated EX-FABP, IL4I1, COX-2, NFKBIA, TNFAIP3 and the Jak STAT pathway inhibitors including CISH, SOCS1 and SOCS3 are beneficial to ALV-J survival in chicken macrophages. We speculated that ALV-J tropism for macrophages helps to establish a latent infection in chicken MDM from 6 to 36 hpi. The present study provides a comprehensive view of the interactions between macrophages and ALV-J. It suggests the mechanisms of defense of chicken macrophages against ALV-J invasion and how ALV-J escape the host innate immune responses. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13567-019-0638-y) contains supplementary material, which is available to authorized users. |
3,531 | Projections of Ebola outbreak size and duration with and without vaccine use in Équateur, Democratic Republic of Congo, as of May 27, 2018 | As of May 27, 2018, 6 suspected, 13 probable and 35 confirmed cases of Ebola virus disease (EVD) had been reported in Équateur Province, Democratic Republic of Congo. We used reported case counts and time series from prior outbreaks to estimate the total outbreak size and duration with and without vaccine use. We modeled Ebola virus transmission using a stochastic branching process model that included reproduction numbers from past Ebola outbreaks and a particle filtering method to generate a probabilistic projection of the outbreak size and duration conditioned on its reported trajectory to date; modeled using high (62%), low (44%), and zero (0%) estimates of vaccination coverage (after deployment). Additionally, we used the time series for 18 prior Ebola outbreaks from 1976 to 2016 to parameterize the Thiel-Sen regression model predicting the outbreak size from the number of observed cases from April 4 to May 27. We used these techniques on probable and confirmed case counts with and without inclusion of suspected cases. Probabilistic projections were scored against the actual outbreak size of 54 EVD cases, using a log-likelihood score. With the stochastic model, using high, low, and zero estimates of vaccination coverage, the median outbreak sizes for probable and confirmed cases were 82 cases (95% prediction interval [PI]: 55, 156), 104 cases (95% PI: 58, 271), and 213 cases (95% PI: 64, 1450), respectively. With the Thiel-Sen regression model, the median outbreak size was estimated to be 65.0 probable and confirmed cases (95% PI: 48.8, 119.7). Among our three mathematical models, the stochastic model with suspected cases and high vaccine coverage predicted total outbreak sizes closest to the true outcome. Relatively simple mathematical models updated in real time may inform outbreak response teams with projections of total outbreak size and duration. |
3,532 | The association between low glucose-6-phosphate dehydrogenase activity level and hepatitis B virus infection among pre-pregnant reproductive-age Chinese females | The relationship between females with low glucose-6-phosphate dehydrogenase activity level (LG6PD) and HBV infection is unclear. We conducted a cross sectional study of 124 406 reproductive-age Chinese females who participated in the National Free Pre-conception Check-up Projects to investigate the risk of HBV infection among females with LG6PD and its effect on liver enzyme. Based on HBV serological test results, the participants were divided into the susceptible, immunized, and HBV infected groups. The multivariable-adjusted odds ratios (ORs) for HBV infection in LG6PD participants were 1.71 (95% confidence interval (CI): 1.45–2.01) and 1.41 (95% CI: 1.23–1.62), respectively with the susceptible and immunized participants as references, compared to those without LG6PD. Participants with HBV infection only and combined with HBV infection and LG6PD had 184% and 249% significantly higher risks of elevated alanine transaminase (ALT) (susceptible participants as reference). If the immunized participants were used as reference, significant higher odds of elevated ALT occurred (3.48 (95% CI: 3.18–3.80), 4.28 (95% CI: 2.92–6.28)). Thus, reproductive-age females with LG6PD had a higher prevalence of HBV infection, and LG6PD might exacerbate ALT elevation in HBV infected females. Our findings underscore the need to explore collaborative management approaches for these two diseases among reproductive-age females for maternal and child health. |
3,533 | Rodents Versus Pig Model for Assessing the Performance of Serotype Chimeric Ad5/3 Oncolytic Adenoviruses | Oncolytic adenoviruses (Ad) are promising tools for cancer therapeutics. Most Ad-based therapies utilize species C serotypes, with Adenovirus type 5 (Ad5) most commonly employed. Prior clinical trials demonstrated low efficiency of oncolytic Ad5 vectors, mainly due to the absence of Ad5 primary receptor (Coxsackie and Adenovirus Receptor, CAR) on cancer cells. Engineering serotype chimeric vectors (Ad5/3) to utilize Adenovirus type 3 (Ad3) receptors has greatly improved their oncolytic potential. Clinical translation of these infectivity-enhanced vectors has been challenging due to a lack of replication permissive animal models. In this study, we explored pigs as a model to study the performance of fiber-modified Ad5/3 chimeric vectors. As a control, the Ad5 fiber-unmodified virus was used. We analyzed binding, gene transfer, replication, and cytolytic ability of Ad5 and Ad5/3 in various non-human cell lines (murine, hamster, canine, porcine). Among all tested cell lines only porcine cells supported active binding and replication of Ad5/3. Syrian hamster cells supported Ad5 replication but showed no evidence of productive viral replication after infection with Ad5/3 vectors. Transduction and replication ability of Ad5/3 in porcine cells outperformed Ad5, a phenomenon often observed in human cancer cell lines. Replication of Ad5 and Ad5/3 was subsequently evaluated in vivo in immunocompetent pigs. Quantitative PCR analyses 7 days post infection revealed Ad5 and Ad5/3 DNA and replication-dependent luciferase activity in the swine lungs and spleen indicating active replication in these tissues. These studies demonstrated the flaws in using Syrian hamsters for testing serotype chimeric Ad5/3 vectors. This is the first report to validate the pig as a valuable model for preclinical testing of oncolytic adenoviruses utilizing Adenovirus type 3 receptors. We hope that these data will help to foster the clinical translation of oncolytic adenoviruses including those with Ad3 retargeted tropism. |
3,534 | Diagnostic tests for Crimean-Congo haemorrhagic fever: a widespread tickborne disease | Crimean-Congo haemorrhagic fever (CCHF) is a widespread tickborne disease that circulates in wild and domestic animal hosts, and causes severe and often fatal haemorrhagic fever in infected humans. Due to the lack of treatment options or vaccines, and a high fatality rate, CCHF virus (CCHFV) is considered a high-priority pathogen according to the WHO R&D Blueprint. Several commercial reverse transcriptase PCR (RT-PCR) and serological diagnostic assays for CCHFV are already available, including febrile agent panels to distinguish CCHFV from other viral haemorrhagic fever agents; however, the majority of international laboratories use inhouse assays. As CCHFV has numerous amplifying animal hosts, a cross-sectoral ‘One Health’ approach to outbreak prevention is recommended to enhance notifications and enable early warning for genetic and epidemiological shifts in the human, animal and tick populations. However, a lack of guidance for surveillance in animals, harmonisation of case identification and validated serodiagnostic kits for animal testing hinders efforts to strengthen surveillance systems. Additionally, as RT-PCR tests tend to be lineage-specific for regional circulating strains, there is a need for pan-lineage sensitive diagnostics. Adaptation of existing tests to point-of-care molecular diagnostic platforms that can be implemented in clinic or field-based settings would be of value given the potential for CCHFV outbreaks in remote or low-resource areas. Finally, improved access to clinical specimens for validation of diagnostics would help to accelerate development of new tests. These gaps should be addressed by updated target product profiles for CCHFV diagnostics. |
3,535 | Diagnostics for Lassa fever virus: a genetically diverse pathogen found in low-resource settings | Lassa fever virus (LASV) causes acute viral haemorrhagic fever with symptoms similar to those seen with Ebola virus infections. LASV is endemic to West Africa and is transmitted through contact with excretions of infected Mastomys natalensis rodents and other rodent species. Due to a high fatality rate, lack of treatment options and difficulties with prevention and control, LASV is one of the high-priority pathogens included in the WHO R&D Blueprint. The WHO LASV vaccine strategy relies on availability of effective diagnostic tests. Current diagnostics for LASV include in-house and commercial (primarily research-only) laboratory-based serological and nucleic acid amplification tests. There are two commercially available (for research use only) rapid diagnostic tests (RDTs), and a number of multiplex panels for differential detection of LASV infection from other endemic diseases with similar symptoms have been evaluated. However, a number of diagnostic gaps remain. Lineage detection is a challenge due to the genomic diversity of LASV, as pan-lineage sensitivity for both molecular and immunological detection is necessary for surveillance and outbreak response. While pan-lineage ELISA and RDTs are commercially available (for research use only), validation and external quality assessment (EQA) is needed to confirm detection sensitivity for all known or relevant strains. Variable sensitivity of LASV PCR tests also highlights the need for improved validation and EQA. Given that LASV outbreaks typically occur in low-resource settings, more options for point-of-care testing would be valuable. These requirements should be taken into account in target product profiles for improved LASV diagnostics. |
3,536 | Acute fibrinous and organizing pneumonia: A case report | RATIONALE: Acute fibrinous and organizing pneumonia (AFOP) is an uncommon type of acute lung injury associated with infection, connective tissue disorders, drug exposure, and hematologic malignancies. PATIENT CONCERNS: A 53-year-old female presented with intermittent fever, chills, and dry cough since 10 days. Chest computed tomography scan showed multiple bilateral patchy infiltrates. PPD skin test was positive but tuberculosis antibody test and T-SPOT were negative. DIAGNOSES: Histologic examination revealed massive fibrinous exudation with organization within alveolar spaces and scattered neutrophilic infiltrates, which was consistent with AFOP. INTERVENTIONS: This patient was treated with prednisolone therapy. OUTCOMES: Chest radiograph improvement and symptom improvement, including fever and respiratory symptoms, was observed after 2 week of oral prednisolone treatment. After 9-month of treatment, the patient was asymptomatic with stable disease and improved quality of life. LESSONS: AFOP has unique pathologic manifestations; however, the condition is liable to be misdiagnosed as community-acquired pneumonia ortuberculosis. Antibiotics are ineffective, while some patients show good response to glucocorticoid therapy. |
3,537 | Multidrug Resistant Gram-Negative Bacteria in Community-Acquired Pneumonia | This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2019. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2019. Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901. |
3,538 | Dynamic Expression of Interferon Lambda Regulated Genes in Primary Fibroblasts and Immune Organs of the Chicken | Interferons (IFNs) are pleiotropic cytokines that establish a first line of defense against viral infections in vertebrates. Several types of IFN have been identified; however, limited information is available in poultry, especially using live animal experimental models. IFN-lambda (IFN-λ) has recently been shown to exert a significant antiviral impact against viral pathogens in mammals. In order to investigate the in vivo potential of chicken IFN-λ (chIFN-λ) as a regulator of innate immunity, and potential antiviral therapeutics, we profiled the transcriptome of chIFN-λ-stimulated chicken immune organs (in vivo) and compared it with primary chicken embryo fibroblasts (in vitro). Employing the baculovirus expression vector system (BEVS), recombinant chIFN-λ3 (rchIFN-λ3) was produced and its biological activities were demonstrated. The rchIFNλ3 induced a great array of IFN-regulated genes in primary chicken fibroblast cells. The transcriptional profiling using RNA-seq and subsequent bioinformatics analysis (gene ontology, differential expressed genes, and KEGGs analysis) of the bursa of Fabricious and the thymus demonstrated an upregulation of crucial immune genes (viperin, IKKB, CCL5, IL1β, and AP1) as well as the antiviral signaling pathways. Interestingly, this experimental approach revealed contrasting evidence of the antiviral potential of chIFN-λ in both in vivo and in vitro models. Taken together, our data signifies the potential of chIFN-λ as a potent antiviral cytokine and highlights its future possible use as an antiviral therapeutic in poultry. |
3,539 | Characterization of Host and Bacterial Contributions to Lung Barrier Dysfunction Following Co-infection with 2009 Pandemic Influenza and Methicillin Resistant Staphylococcus aureus | Influenza viruses are a threat to global public health resulting in ~500,000 deaths each year. Despite an intensive vaccination program, influenza infections remain a recurrent, yet unsolved public health problem. Secondary bacterial infections frequently complicate influenza infections during seasonal outbreaks and pandemics, resulting in increased morbidity and mortality. Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), is frequently associated with these co-infections, including the 2009 influenza pandemic. Damage to alveolar epithelium is a major contributor to severe influenza-bacterial co-infections and can result in gas exchange abnormalities, fluid leakage, and respiratory insufficiency. These deleterious manifestations likely involve both pathogen- and host-mediated mechanisms. However, there is a paucity of information regarding the mechanisms (pathogen- and/or host-mediated) underlying influenza-bacterial co-infection pathogenesis. To address this, we characterized the contributions of viral-, bacterial-, and host-mediated factors to the altered structure and function of alveolar epithelial cells during co-infection with a focus on the 2009 pandemic influenza (pdm2009) and MRSA. Here, we characterized pdm2009 and MRSA replication kinetics, temporal host kinome responses, modulation of MRSA virulence factors, and disruption of alveolar barrier integrity in response to pdm2009-MRSA co-infection. Our results suggest that alveolar barrier disruption during co-infection is mediated primarily through host response dysregulation, resulting in loss of alveolar barrier integrity. |
3,540 | A Survey of Recent Adenoviral Respiratory Pathogens in Hong Kong Reveals Emergent and Recombinant Human Adenovirus Type 4 (HAdV-E4) Circulating in Civilian Populations | Human adenovirus type 4 (HAdV-E4), which is intriguingly limited to military populations, causes acute respiratory disease with demonstrated morbidity and mortality implications. This respiratory pathogen contains genome identity with chimpanzee adenoviruses, indicating zoonotic origins. A signature of these “old” HAdV-E4 is the absence of a critical replication motif, NF-I, which is found in all HAdV respiratory pathogens and most HAdVs. However, our recent survey of flu-like disease in children in Hong Kong reveals that the emergent HAdV-E4 pathogens circulating in civilian populations contain NF-I, indicating recombination and reflecting host-adaptation that enables the “new” HAdV-E4 to replicate more efficiently in human cells and foretells more potential HAdV-E4 outbreaks in immune-naïve civilian populations. Special attention should be paid by clinicians to this emergent and recombinant HAdV-E4 circulating in civilian populations. |
3,541 | Human Polyclonal Antibodies Produced from Transchromosomal Bovine Provides Prophylactic and Therapeutic Protections Against Zika Virus Infection in STAT2 KO Syrian Hamsters | Zika virus (ZIKV) infection can cause severe congenital diseases, such as microcephaly, ocular defects and arthrogryposis in fetuses, and Guillain–Barré syndrome in adults. Efficacious therapeutic treatments for infected patients, as well as prophylactic treatments to prevent new infections are needed for combating ZIKV infection. Here, we report that ZIKV-specific human polyclonal antibodies (SAB-155), elicited in transchromosomal bovine (TcB), provide significant protection from infection by ZIKV in STAT2 knockout (KO) golden Syrian hamsters both prophylactically and therapeutically. These antibodies also prevent testicular lesions in this hamster model. Our data indicate that antibody-mediated immunotherapy is effective in treating ZIKV infection. Because suitable quantities of highly potent human polyclonal antibodies can be quickly produced from the TcB system against ZIKV and have demonstrated therapeutic efficacy in a small animal model, they have the potential as an effective countermeasure against ZIKV infection. |
3,542 | Transmission of Respiratory Syncytial Virus Among Children Under 5 Years in Households of Rural Communities, the Philippines | BACKGROUND: To develop a more effective vaccination strategy for reducing the impact of respiratory syncytial virus (RSV) infection, especially in young infants (<6 months old), it is necessary to understand the transmission dynamics of RSV. METHODS: We conducted a community-based prospective cohort study from 2014 to 2016 in Biliran Province, the Philippines, on children <5 years old. We collected nasopharyngeal swabs from symptomatic children with acute respiratory infection (ARI) during household visits and at health facilities. In households (n = 181) with RSV-positive ARI cases (RSV-ARI), we also identified ARI episodes among other children <5 years old in the same household. In addition, we determined the serial interval to estimate the basic reproduction number (R(0)), the average number of secondary cases generated by a single primary case. RESULTS: In the 181 households analyzed, we found 212 RSV-ARI in 152 households with a single case and 29 households with multiple cases, which included 29 1st RSV-ARI and 31 2nd RSV-ARI. We also found possible index cases among children <5 years old in the same household for 29.0% (18 of 62) of young infants with RSV-ARI. The estimated mean serial interval was 3.2 days, and R(0) was estimated to be 0.92–1.33 for RSV-A and 1.04–1.76 for RSV-B, which varied between different times (2014 and 2015) and places. CONCLUSIONS: Young infants are likely to acquire RSV infection from older children in the same household. Therefore, vaccination targeting older children might protect infants from RSV infection. |
3,543 | C3P3-G1: first generation of a eukaryotic artificial cytoplasmic expression system | Most eukaryotic expression systems make use of host-cell nuclear transcriptional and post-transcriptional machineries. Here, we present the first generation of the chimeric cytoplasmic capping-prone phage polymerase (C3P3-G1) expression system developed by biological engineering, which generates capped and polyadenylated transcripts in host-cell cytoplasm by means of two components. First, an artificial single-unit chimeric enzyme made by fusing an mRNA capping enzyme and a DNA-dependent RNA polymerase. Second, specific DNA templates designed to operate with the C3P3-G1 enzyme, which encode for the transcripts and their artificial polyadenylation. This system, which can potentially be adapted to any in cellulo or in vivo eukaryotic expression applications, was optimized for transient expression in mammalian cells. C3P3-G1 shows promising results for protein production in Chinese Hamster Ovary (CHO-K1) cells. This work also provides avenues for enhancing the performances for next generation C3P3 systems. |
3,544 | Free Fatty Acids’ Level and Nutrition in Critically Ill Patients and Association with Outcomes: A Prospective Sub-Study of PermiT Trial | Objectives: The objectives of this study were to evaluate the clinical and nutritional correlates of high free fatty acids (FFAs) level in critically ill patients and the association with outcomes, and to study the effect of short-term caloric restriction (permissive underfeeding) on FFAs level during critical illness. Patients/Method: In this pre-planned sub-study of the PermiT (Permissive Underfeeding vs. Target Enteral Feeding in Adult Critically Ill Patients) trial, we included critically ill patients who were expected to stay for ≥14 days in the intensive care unit. We measured FFAs level on day 1, 3, 5, 7, and 14 of enrollment. Of 70 enrolled patients, 23 (32.8%) patients had high FFAs level (baseline FFAs level >0.45 mmol/L in females and >0.6 mmol/L in males). Results: Patients with high FFAs level were significantly older and more likely to be females and diabetics and they had lower ratio of partial pressure of oxygen to the fraction of inspired oxygen, higher creatinine, and higher total cholesterol levels than those with normal FFAs level. During the study period, patients with high FFAs level had higher blood glucose and required more insulin. On multivariable logistic regression analysis, the predictors of high baseline FFAs level were diabetes (adjusted odds ratio (aOR): 5.36; 95% confidence interval (CI): 1.56, 18.43, p = 0.008) and baseline cholesterol level (aOR, 4.29; 95% CI: 11.64, 11.19, p = 0.003). Serial levels of FFAs did not differ with time between permissive underfeeding and standard feeding groups. FFAs level was not associated with 90-day mortality (aOR: 0.49; 95% CI: 0.09, 2.60, p = 0.40). Conclusion: We conclude that high FFAs level in critically ill patients is associated with features of metabolic syndrome and is not affected by short-term permissive underfeeding. |
3,545 | Quality Screening of Incorrectly Folded Soluble Aggregates from Functional Recombinant Proteins | Solubility is the prime criterion for determining the quality of recombinant proteins, yet it often fails to represent functional activity due to the involvement of non-functional, misfolded, soluble aggregates, which compromise the quality of recombinant proteins. However, guidelines for the quality assessment of soluble proteins have neither been proposed nor rigorously validated experimentally. Using the aggregation-prone enhanced green-fluorescent protein (EGFP) folding reporter system, we evaluated the folding status of recombinant proteins by employing the commonly used sonication and mild lysis of recombinant host cells. We showed that the differential screening of solubility and folding competence is crucial for improving the quality of recombinant proteins without sacrificing their yield. These results highlight the importance of screening out incorrectly folded soluble aggregates at the initial purification step to ensure the functional quality of recombinant proteins. |
3,546 | Appropriate scaling approach for evaluating peak VO(2) development in Southern Chinese 8 to 16 years old | OBJECTIVE: To investigate scaling approaches for evaluating the development of peak VO(2) and improving the identification of low cardiopulmonary fitness in Southern Chinese children and adolescents. METHODS: Nine hundred and twenty Chinese children and adolescents (8 to 16 years) underwent graded cardiopulmonary exercise test on a treadmill until volitional exhaustion. Peak VO(2) was corrected for the effects of body mass by ratio or allometric scaling. Z score equations for predicting peak VO(2) were developed. Correlations between scaled peak VO(2), z scores, body size and age were tested to examine the effectiveness of the approach. RESULTS: Eight hundred and fifty-two participants (48% male) were included in the analyses. Absolute peak VO(2) significantly increased with age in both sexes (both P<0.05), while ratio-scaled peak VO(2) increased only in males (P<0.05). Allometrically scaled peak VO(2) increased from 11 years in both sexes, plateauing by 12 years in girls and continuing to rise until 15 years in boys. Allometically scaled peak VO(2) was not correlated with body mass, but remained correlated with height and age in all but the older girls. Peak VO(2) z score was not correlated with body mass, height or age. CONCLUSIONS: Absolute and allometric scaled peak VO(2) values are provided for Hong Kong Chinese children and adolescents by age and sex. Peak VO(2) z scores improve the evaluation of cardiopulmonary fitness, allowing comparisons across ages and sex and will likely provide a better metric for tracking change over time in children and adolescents, regardless of body size and age. |
3,547 | Influenza C virus in pre-school children with respiratory infections: retrospective analysis of data from the national influenza surveillance system in Germany, 2012 to 2014 | INTRODUCTION: Recent data on influenza C virus indicate a possible higher clinical impact in specified patient populations than previously thought. AIM: We aimed to investigate influenza C virus circulation in Germany. METHODS: A total of 1,588 samples from 0 to 4 year-old children presenting as outpatients with influenza-like illness (ILI) or acute respiratory infection were analysed retrospectively. The samples represented a subset of all samples from the German national surveillance system for influenza in this age group in 2012–14. The presence of influenza C virus was investigated by real-time PCR. For positive samples, information on symptoms as well as other respiratory virus co-infections was considered. Retrieved influenza C viral sequences were phylogenetically characterised. RESULTS: Influenza C viral RNA was detected in 20 (1.3% of) samples, including 16 during the 2012/13 season. The majority (18/20) of influenza C-positive patients had ILI according to the European Union definition, one patient had pneumonia. Viruses belonged to the C/Sao Paulo and C/Kanagawa lineages. Most (11/20) samples were co-infected with other respiratory viruses. CONCLUSION: Our data are the first on influenza C virus circulation in Germany and notably from a European national surveillance system. The low detection frequency and the identified virus variants confirm earlier observations outside a surveillance system. More virus detections during the 2012/13 season indicate a variable circulation intensity in the different years studied. Influenza C virus can be considered for ILI patients. Future studies addressing its clinical impact, especially in patients with severe disease are needed. |
3,548 | An Effective Neutralizing Antibody Against Influenza Virus H1N1 from Human B Cells | Influenza is a contagious acute respiratory disease caused by the influenza virus infection. Hemagglutinin (HA) is an important target in the therapeutic treatment and diagnostic detection of the influenza virus. Influenza A virus encompasses several different HA subtypes with different strains, which are constantly changing. In this study, we identified a fully human H1N1 neutralizing antibody (32D6) via an Epstein-Barr virus-immortalized B cell-based technology. 32D6 specifically neutralizes the clinically isolated H1N1 strains after the 2009 pandemic but not the earlier strains. The epitope was identified through X-ray crystallographic analysis of the 32D6-Fab/HA1 complex structure, which revealed a unique loop conformation located on the top surface of HA. The major region is composed of two peptide segments (residues 172–177 and 206–213), which form an abreast loop conformation. The residue T262 between the two loops forms a conformational epitope for recognition by 32D6. Three water molecules were observed at the interface of HA and the heavy chain, and they may constitute a stabilizing element for the 32D6-HA association. In addition, each 32D6-Fab is likely capable of blocking one HA trimer. This study provides important information on the strain specificity of 32D6 for the therapeutic treatment and detection of viral infection. |
3,549 | High Environmental Stability of Hepatitis B Virus and Inactivation Requirements for Chemical Biocides | Hepatitis B virus (HBV) infection is considered a major public health problem worldwide, and a significant number of reports on nosocomial and occupational outbreaks have been reported. This systematic investigation of HBV stability and susceptibility to different antiseptics revealed that HBV infectivity was very stable, with a half-life of >22 days at 37°C. At 4°C, infectivity was barely reduced for up to 9 months. Different alcohols and commercially available hand antiseptics had a virucidal effect against HBV. We propose that very strict compliance with established hygienic guidelines should be mandatory to avoid and prevent HBV infections. |
3,550 | Capillary leak-syndrome triggered by Maripa virus in French Guiana: case report and implication for pathogenesis | BACKGROUND: We report hereby a severe case of Hantavirus Pulmonary Syndrome” (HPS) induced by Maripa virus in French Guiana and describe the mechanism of severity of the human disease. CASE PRESENTATION: A 47-year- old patient started presenting a prodromic period with fever, dyspnea, cough and head ache. This clinical presentation was followed by a rapid respiratory, hemodynamic and renal failure leading to admission in the ICU. Biological exams revealed an increased haematocrit level with a paradoxical low protein level. Echocardiographic and hemodynamic monitoring showed a normal left ventricular function with low filling pressures, an elevated extravascular lung water index and pulmonary vascular permeability index. These findings were compatible with a capillary leak-syndrome (CLS). CONCLUSIONS: The severity of HPS caused by the virus Maripa in French Guiana can be explained by the tropism of hantavirus for the microvascular endothelial cell leading to a CLS. |
3,551 | The Screening Research of NF-κB Inhibitors from Moutan Cortex Based on Bioactivity-Integrated UPLC-Q/TOF-MS | Inflammation is a common and important pathological process, and nuclear factor-κB (NF-κB) is a key mediator of it. Moutan Cortex (MC), the dried root cortex of Paeonia suffruticosa Andr., is widely used as a remedy for the treatment of inflammatory diseases in Asian region. However, there are few studies on the systematic identification of NF-κB inhibitors of MC. In this study, the effect of inhibiting NF-κB activation of MC was assessed at the cellular level using a tumor necrosis factor-α (TNF-α) induced inflammatory model. Subsequently, ultra-performance liquid chromatography-quadrupole/time of flight-mass spectrometry (UPLC-Q/TOF-MS) combined with biological activity assay was established to screen and identify potential anti-inflammatory ingredients in MC. The results revealed that MC significantly inhibited the activation of NF-κB. Seven potential NF-κB inhibitors were screened from MC, including oxypaeoniflorin, paeoniflorin, galloylpaeoniflorin, benzoyloxypaeoniflorin, mudanpioside C, gallic acid, and paeonol. Among them, the NF-κB inhibitor activity of galloylpaeoniflorin, benzoyloxypaeoniflorin, and mudanpioside C is first reported here. In conclusion, the anti-inflammatory activity of MC was associated with the seven components mentioned above. And the bioactivity-integrated UPLC-Q/TOF which contains both chemical and bioactive details is suitable for screening active ingredients from natural medicines. |
3,552 | Identification of Urinary CD44 and Prosaposin as Specific Biomarkers of Urinary Tract Infections in Children With Neurogenic Bladders | PURPOSE: Distinguishing urinary tract infection (UTI) from urinary tract colonization (UTC) in children with neurogenic bladders who require clean intermittent catheterization (CIC) is challenging. Our objective was to identify urinary proteins to distinguish UTI from UTC in CIC-dependent children that have potential to serve as objective markers of UTI. EXPERIMENTAL DESIGN: A total of 10 CIC-dependent children were included in the mass spectrometry analysis (UTI = 5, UTC = 5). Quantitative profiling of urine proteins with isobaric protein labeling was performed using tandem mass spectrometry. Candidate markers were normalized using a collective mixture of proteins from all samples. Relative quantitative abundance of proteins across all samples were compared. Proteins with >50% change in the average abundance were identified as proteins of interest, which were then measured using enzyme-linked immunosorbent assay (ELISA) in an additional 40 samples (no growth = 10, UTC = 15, UTI = 15). RESULTS: Mass spectrometry revealed 8 differentially expressed proteins. Of these, apolipoprotein D, alpha-amylase 2B, non-secretory ribonuclease, CD44 antigen, and prosaposin were measurable by ELISA. Concentrations of both CD44 and prosaposin were significantly higher in UTI, with area under the curves (AUCs) of 0.72 and 0.78, respectively. CONCLUSION: Urinary CD44 and prosaposin are candidate markers that may assist with the diagnosis of UTI in CIC-dependent children. |
3,553 | Cellular entry and uncoating of naked and quasi-enveloped human hepatoviruses | Many ‘non-enveloped’ viruses, including hepatitis A virus (HAV), are released non-lytically from infected cells as infectious, quasi-enveloped virions cloaked in host membranes. Quasi-enveloped HAV (eHAV) mediates stealthy cell-to-cell spread within the liver, whereas stable naked virions shed in feces are optimized for environmental transmission. eHAV lacks virus-encoded surface proteins, and how it enters cells is unknown. We show both virion types enter by clathrin- and dynamin-dependent endocytosis, facilitated by integrin β(1), and traffic through early and late endosomes. Uncoating of naked virions occurs in late endosomes, whereas eHAV undergoes ALIX-dependent trafficking to lysosomes where the quasi-envelope is enzymatically degraded and uncoating ensues coincident with breaching of endolysosomal membranes. Neither virion requires PLA2G16, a phospholipase essential for entry of other picornaviruses. Thus naked and quasi-enveloped virions enter via similar endocytic pathways, but uncoat in different compartments and release their genomes to the cytosol in a manner mechanistically distinct from other Picornaviridae. |
3,554 | Yersinia pestis Interacts With SIGNR1 (CD209b) for Promoting Host Dissemination and Infection | Yersinia pestis, a Gram-negative bacterium and the etiologic agent of plague, has evolved from Yersinia pseudotuberculosis, a cause of a mild enteric disease. However, the molecular and biological mechanisms of how Y. pseudotuberculosis evolved to such a remarkably virulent pathogen, Y. pestis, are not clear. The ability to initiate a rapid bacterial dissemination is a characteristic hallmark of Y. pestis infection. A distinguishing characteristic between the two Yersinia species is that Y. pseudotuberculosis strains possess an O-antigen of lipopolysaccharide (LPS) while Y. pestis has lost the O-antigen during evolution and therefore exposes its core LPS. In this study, we showed that Y. pestis utilizes its core LPS to interact with SIGNR1 (CD209b), a C-type lectin receptor on antigen presenting cells (APCs), leading to bacterial dissemination to lymph nodes, spleen and liver, and the initiation of a systemic infection. We therefore propose that the loss of O-antigen represents a critical step in the evolution of Y. pseudotuberculosis into Y. pestis in terms of hijacking APCs, promoting bacterial dissemination and causing the plague. |
3,555 | An outbreak of leptospirosis with predominant cardiac involvement: a case series | BACKGROUND: Severe leptospirosis is known to cause multi organ dysfunction including cardiac involvement. In the clinical setting with limited resources, high degree of suspicion is needed to diagnose cardiac involvement including myocarditis. Although myocarditis is not reported as a common complication due to lack of diagnostic facilities, there are evidence to support myocarditis is more prevalent in post mortem studies of patients died due to leptospirosis. We present a case series of severe leptospirosis with cardiac involvement observed during a period of one month at Colombo-North Teaching Hospital, Sri Lanka. CASE PRESENTATION: We report here five patients with severe leptospirosis complicated with cardiac involvement, admitted to a single medical ward, Colombo-North Teaching Hospital, Sri Lanka during a one-month period. Out of six suspected leptospirosis patients admitted during that period, five in a raw developed severe leptospirosis with cardiac involvement. In this case series, four patients were confirmed serologically or quantitative PCR and one patient had possible leptospirosis. All patients developed shock during their course of illness. Two patients developed rapid atrial fibrillation. One patient had dynamic T wave changes in ECG and the other two had sinus tachycardia. Two patients had evidence of myocarditis in 2D echocardiogram, whereas other two patients had nonspecific findings and one patient had normal 2D echocardiogram. All five patients had elevated cardiac troponin I titre and it was normalized with the recovery. All five patients developed acute kidney injury. Four patients needed inotropic/vasopressor support to maintain mean arterial pressure and one patient recovered from shock with fluid resuscitation. All patients were recovered from their illness and repeat 2D echocardiograms after recovery did not show residual complications. One patient had serologically proven dengue co-infection with leptospirosis. CONCLUSIONS: Myocarditis and cardiac involvement in leptospirosis may be overlooked due to non-specific clinical findings and co-existing multi-organ dysfunction. Atypical presentation of this case series may be due to micro-geographic variation and unusual outbreak of leptospirosis. Co-infection of dengue with leptospirosis should be considered in managing patients especially in endemic areas. |
3,556 | Hemorrhagic Fever-Causing Arenaviruses: Lethal Pathogens and Potent Immune Suppressors | Hemorrhagic fevers (HF) resulting from pathogenic arenaviral infections have traditionally been neglected as tropical diseases primarily affecting African and South American regions. There are currently no FDA-approved vaccines for arenaviruses, and treatments have been limited to supportive therapy and use of non-specific nucleoside analogs, such as Ribavirin. Outbreaks of arenaviral infections have been limited to certain geographic areas that are endemic but known cases of exportation of arenaviruses from endemic regions and socioeconomic challenges for local control of rodent reservoirs raise serious concerns about the potential for larger outbreaks in the future. This review synthesizes current knowledge about arenaviral evolution, ecology, transmission patterns, life cycle, modulation of host immunity, disease pathogenesis, as well as discusses recent development of preventative and therapeutic pursuits against this group of deadly viral pathogens. |
3,557 | Quantifying heterogeneous contact patterns in Japan: a social contact survey | BACKGROUND: Social contact surveys can greatly help in quantifying the heterogeneous patterns of infectious disease transmission. The present study aimed to conduct a contact survey in Japan, offering estimates of contact by age and location and validating a social contact matrix using a seroepidemiological dataset of influenza. METHODS: An internet-based questionnaire survey was conducted, covering all 47 prefectures in Japan and including a total of 1476 households. The social contact matrix was quantified assuming reciprocity and using the maximum likelihood method. By imposing several parametric assumptions for the next-generation matrix, the empirical seroepidemiological data of influenza A (H1N1) 2009 was analysed and we estimated the basic reproduction number, R(0). RESULTS: In total, the reported number of contacts on weekdays was 10,682 whereas that on weekend days was 8867. Strong age-dependent assortativity was identified. Forty percent of weekday contacts took place at schools or workplaces, but that declined to 14% on weekends. Accounting for the age-dependent heterogeneity with the known social contact matrix, the minimum value of the Akaike information criterion was obtained and R(0) was estimated at 1.45 (95% confidence interval: 1.42, 1.49). CONCLUSIONS: Survey datasets will be useful for parameterizing the heterogeneous transmission model of various directly transmitted infectious diseases in Japan. Age-dependent assortativity, especially among children, along with numerous contacts in school settings on weekdays implies the potential effectiveness of school closure. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12976-019-0102-8) contains supplementary material, which is available to authorized users. |
3,558 | Targeting pericytes for neurovascular regeneration | Pericytes, as a key cellular part of the blood-brain barrier, play an important role in the maintenance of brain neurovascular unit. These cells participate in brain homeostasis by regulating vascular development and integrity mainly through secreting various factors. Pericytes per se show different restorative properties after blood-brain barrier injury. Upon the occurrence of brain acute and chronic diseases, pericytes provoke immune cells to regulate neuro-inflammatory conditions. Loss of pericytes in distinct neurologic disorders intensifies blood-brain barrier permeability and leads to vascular dementia. The therapeutic potential of pericytes is originated from the unique morphological shape, location, and their ability in providing vast paracrine and juxtacrine interactions. A subset of pericytes possesses multipotentiality and exhibit trans-differentiation capacity in the context of damaged tissue. This review article aimed to highlight the critical role of pericytes in restoration of the blood-brain barrier after injury by focusing on the dynamics of pericytes and cross-talk with other cell types. |
3,559 | Intratracheal Administration of siRNA Triggers mRNA Silencing in the Lung to Modulate T Cell Immune Response and Lung Inflammation | Clinical application of siRNA-based therapeutics outside of the liver has been hindered by the inefficient delivery of siRNA effector molecules into extra-hepatic organs and cells of interest. To understand the parameters that enable RNAi activity in vivo, it is necessary to develop a systematic approach to identify which cells within a tissue are permissive to oligonucleotide internalization and activity. In the present study, we evaluate the distribution and activity within the lung of chemically stabilized siRNA to characterize cell-type tropism and structure-activity relationship. We demonstrate intratracheal delivery of fully modified siRNA for RNAi-mediated target knockdown in lung CD11c(+) cells (dendritic cells, alveolar macrophages) and alveolar epithelial cells. Finally, we use an allergen-induced model of lung inflammation to demonstrate the capacity of inhaled siRNA to induce target knockdown in dendritic cells and ameliorate lung pathology. |
3,560 | Evaluation of the Inhibitory Effects of (E)-1-(2-hydroxy-4,6-dimethoxyphenyl)-3-(naphthalen-1-yl)prop-2-en-1-one (DiNap), a Natural Product Analog, on the Replication of Type 2 PRRSV In Vitro and In Vivo | DiNap [(E)-1-(2-hydroxy-4,6-dimethoxyphenyl)-3-(naphthalen-1-yl)prop-2-en-1-one], an analog of a natural product (the chalcone flavokawain), was synthesized and characterized in this study. Porcine reproductive and respiratory syndrome virus (PRRSV) is the most challenging threat to the swine industry worldwide. Currently, commercially available vaccines are ineffective for controlling porcine reproductive and respiratory syndrome (PRRS) in pigs. Therefore, a pharmacological intervention may represent an alternative control measure for PRRSV infection. Hence, the present study evaluated the effects of DiNap on the replication of VR2332 (a prototype strain of type 2 PRRSV). Initially, in vitro antiviral assays against VR2332 were performed in MARC-145 cells and porcine alveolar macrophages (PAMs). Following this, a pilot study was conducted in a pig model to demonstrate the effects of DiNap following VR2332 infection. DiNap inhibited VR2332 replication in both cell lines in a dose-dependent manner, and viral growth was completely suppressed at concentrations ≥0.06 mM, without significant cytotoxicity. Consistent with these findings, in the pig study, DiNap also reduced viral loads in the serum and lungs and enhanced the weight gain of pigs following VR2332 infection, as indicated by comparison of the DiNap-treated groups to the untreated control (NC) group. In addition, DiNap-treated pigs had fewer gross and microscopic lesions in their lungs than NC pigs. Notably, virus transmission was also delayed by approximately 1 week in uninfected contact pigs within the same group after treatment with DiNap. Taken together, these results suggest that DiNap has potential anti-PRRSV activity and could be useful as a prophylactic or post-exposure treatment drug to control PRRSV infection in pigs. |
3,561 | Design and Synthesis of Novel Anti-Proliferative Emodin Derivatives and Studies on their Cell Cycle Arrest, Apoptosis Pathway and Migration | Emodin is a cell arrest and apoptosis-inducing compound that is widely distributed in different plants (rhubarb, aloe), lichens and terrestrial fungi, and also isolated from marine-derived fungi and marine sponge-associated fungi. In this study, we designed and synthesized a novel series of emodin derivatives by binding emodin to an amino acid using linkers of varying lengths and composition, and evaluated their anti-proliferative activities using HepG2 cells (human hepatic carcinoma), MCF-7 cells (human breast cancer) and human normal liver L02 cells. Most of these derivatives showed moderate to potent anti-proliferative activities. Notably, compound 7a exhibited potent anti-proliferative activity against HepG2 cells with the half maximal inhibitory concentration (IC(50)) value of 4.95 µM, which was enhanced 8.8-fold compared to the parent compound emodin (IC(50) = 43.87 µM), and it also exhibited better selective anti-proliferative activity and specificity than emodin. Moreover, further experiments demonstrated that compound 7a displayed a significant efficacy of inducing apoptosis through mitochondrial pathway via release of cytochrome c from mitochondria and subsequent activation of caspase-9 and caspase-3, inducing cell arrest at G0/G1 phase, as well as suppression of cell migration of tumor cells. The preliminary results suggested that compound 7a could be a promising lead compound for the discovery of novel anti-tumor drugs and has the potential for further investigations as an anti-cancer drug. |
3,562 | Advances in Zika Virus–Host Cell Interaction: Current Knowledge and Future Perspectives | Emerging mosquito-transmitted RNA viruses, such as Zika virus (ZIKV) and Chikungunya represent human pathogens of an immense global health problem. In particular, ZIKV has emerged explosively since 2007 to cause a series of epidemics in the South Pacific and most recently in the Americas. Although typical ZIKV infections are asymptomatic, ZIKV infection during pregnancy is increasingly associated with microcephaly and other fetal developmental abnormalities. In the last few years, genomic and molecular investigations have established a remarkable progress on the pathogenic mechanisms of ZIKV infection using in vitro and in vivo models. Here, we highlight recent advances in ZIKV-host cell interaction studies, including cellular targets of ZIKV, ZIKV-mediated cell death mechanisms, host cell restriction factors that limit ZIKV replication, and immune evasion mechanisms utilized by ZIKV. Understanding of the mechanisms of ZIKV–host interaction at the cellular level will contribute crucial insights into the development of ZIKV therapeutics and vaccines. |
3,563 | Lethal Influenza in Two Related Adults with Inherited GATA2 Deficiency | The pathogenesis of life-threatening influenza A virus (IAV) disease remains elusive, as infection is benign in most individuals. We studied two relatives who died from influenza. We Sanger sequenced GATA2 and evaluated the mutation by gene transfer, measured serum cytokine levels, and analyzed circulating T- and B-cells. Both patients (father and son, P1 and P2) died in 2011 of H1N1pdm IAV infection at the ages of 54 and 31 years, respectively. They had not suffered from severe or moderately severe infections in the last 17 (P1) and 15 years (P2). A daughter of P1 had died at 20 years from infectious complications. Low B-cell, NK- cell, and monocyte numbers and myelodysplastic syndrome led to sequence GATA2. Patients were heterozygous for a novel, hypomorphic, R396L mutation leading to haplo-insufficiency. B- and T-cell rearrangement in peripheral blood from P1 during the influenza episode showed expansion of one major clone. No T-cell receptor excision circles were detected in P1 and P3 since they were 35 and 18 years, respectively. Both patients presented an exuberant, interferon (IFN)-γ-mediated hypercytokinemia during H1N1pdm infection. No data about patients with viremia was available. Two previously reported adult GATA2-deficient patients died from severe H1N1 IAV infection; GATA2 deficiency may predispose to life-threatening influenza in adulthood. However, a role of other genetic variants involved in immune responses cannot be ruled out. Patients with GATA2 deficiency can reach young adulthood without severe infections, including influenza, despite long-lasting complete B-cell and natural killer (NK) cell deficiency, as well as profoundly diminished T-cell thymic output. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10875-018-0512-0) contains supplementary material, which is available to authorized users. |
3,564 | ACVIM consensus statement on the diagnosis of immune‐mediated hemolytic anemia in dogs and cats | Immune‐mediated hemolytic anemia (IMHA) is an important cause of morbidity and mortality in dogs. IMHA also occurs in cats, although less commonly. IMHA is considered secondary when it can be attributed to an underlying disease, and as primary (idiopathic) if no cause is found. Eliminating diseases that cause IMHA may attenuate or stop immune‐mediated erythrocyte destruction, and adverse consequences of long‐term immunosuppressive treatment can be avoided. Infections, cancer, drugs, vaccines, and inflammatory processes may be underlying causes of IMHA. Evidence for these comorbidities has not been systematically evaluated, rendering evidence‐based decisions difficult. We identified and extracted data from studies published in the veterinary literature and developed a novel tool for evaluation of evidence quality, using it to assess study design, diagnostic criteria for IMHA, comorbidities, and causality. Succinct evidence summary statements were written, along with screening recommendations. Statements were refined by conducting 3 iterations of Delphi review with panel and task force members. Commentary was solicited from several professional bodies to maximize clinical applicability before the recommendations were submitted. The resulting document is intended to provide clinical guidelines for diagnosis of, and underlying disease screening for, IMHA in dogs and cats. These should be implemented with consideration of animal, owner, and geographical factors. |
3,565 | Sequelae of Acute Respiratory Distress Syndrome: Interest of Rehabilitation | CASE PRESENTATION: This clinical case presents the history of a woman hospitalized for acute respiratory distress syndrome (ARDS). A 62-year-old woman, with regular physical activity and no history of respiratory disease or smoking, was hospitalized for moderate ARDS with bilateral pneumonitis. Fourteen days later, she was discharged from the intensive care unit and received respiratory physical therapy. One month later, she experienced exertional dyspnea. A regression of alveolar condensation with persistent sequelae at the pulmonary bases was noted. Three months later, the patient continued daily physical activity with satisfactory tolerance. A reduction in alveolar-capillary transfer, inappropriate hyperventilation upon exercise, and impairment of gas exchanges at maximal effort, suggestive of pulmonary shunt, were demonstrated. At the 6-month evaluation, the patient displayed exertional dyspnea with residual bilateral basal consolidations. Six months later, the dyspnea had ceased. The persistence of bilateral basal interstitial syndrome associated with bronchial dilatation and pleural-based consolidations was noted, as well as a stable impaired alveolar-capillary diffusing capacity. DISCUSSION: Upon discharge from intensive care, pulmonary follow-up should be proposed to ARDS survivors. Moreover, pulmonary function testing at rest and exercise is advised as soon as possible to evaluate the respiratory sequelae. This will help to limit the severity of complications through adapted exercise rehabilitation and then regular physical activity. |
3,566 | An RT-PCR panel for rapid serotyping of dengue virus serotypes 1 to 4 in human serum and mosquito on a field-deployable PCR system | BACKGROUND: Dengue fever, a mosquito-borne disease, is caused by dengue virus (DENV) which includes four major serotypes (DENV-1, -2, -3, and -4). Some serotypes cause more severe diseases than the other; severe dengue is associated with secondary infections by a different serotype. Timely serotyping can provide early warning of dengue epidemics to improve management of patients and outbreaks. A mobile insulated isothermal PCR (iiPCR) system is available to allow molecular detection of pathogens near points of need. METHODOLOGY/PRINCIPLE FINDINGS: In this study, side-by-side comparison with the CDC DENV-1-4 Real Time RT-PCR (qRT-PCR) was performed to evaluate the performance of four singleplex DENV-1–4 serotyping reverse transcription-iiPCR (RT-iiPCR) reagents for DENV subtyping on the mobile PCR system. The four RT-iiPCRs did not react with Zika virus and chikungunya virus; tests with serial dilutions of the four DENV serotypes made in human serum showed they had detection endpoints comparable to those of the reference method, indicating great analytical sensitivity and specificity. Clinical performance of the RT-iiPCR reagents was evaluated by testing 40 serum samples each (around 20 target serotype-positive and 20 DENV-negative); all four reagents had high agreement (97.5–100%) with the reference qRT-PCR. Moreover, testing of mosquitoes separately infected experimentally with each serotype showed that the four reagents detected specifically their target DENV serotypes in mosquito. CONCLUSIONS/SIGNIFICANCE: With analytical and clinical performance comparable to the reference qRT-PCR assay, the four index RT-iiPCR reagents on the field-deployable PCR system can serve as a useful tool for DENV detection near points of needs. |
3,567 | Fish Autophagy Protein 5 Exerts Negative Regulation on Antiviral Immune Response Against Iridovirus and Nodavirus | Autophagy is an important biological activity that maintains homeostasis in eukaryotic cells. However, little is known about the functions of fish autophagy-related genes (Atgs). In this study, we cloned and characterized Atg5, a key gene in the autophagy gene superfamily, from orange-spotted grouper (Epinephelus coioides) (EcAtg5). EcAtg5 encoded a 275-amino acid protein that shared 94 and 81% identity to seabass (Lates calcarifer) and humans (Homo sapiens), respectively. The transcription level of EcAtg5 was significantly increased in cells infected with red-spotted grouper nervous necrosis virus (RGNNV). In cells infected with Singapore grouper iridovirus (SGIV), EcAtg5 expression declined during the early stage of infection and increased in the late stage. Fluorescence microscopy revealed that EcAtg5 mainly localized with a dot-like pattern in the cytoplasm of grouper cells. Overexpression of EcAtg5 significantly increased the replication of RGNNV and SGIV at different levels of detection, as indicated by increased severity of the cytopathic effect, transcription levels of viral genes, and levels of viral proteins. Knockdown of EcAtg5 decreased the replication of RGNNV and SGIV. Further studies showed that overexpression EcAtg5 activated autophagy, decreased expression levels of interferon related cytokines or effectors and pro-inflammatory factors, and inhibited the activation of nuclear factor κB, IFN-sensitive response element, and IFNs. In addition, ectopic expression of EcAtg5 affected cell cycle progression by hindering the G1/S transition. Taken together, our results demonstrated that fish Atg5 exerted a crucial role in virus replication by promoting autophagy, down-regulating antiviral IFN responses, and affecting the cell cycle. |
3,568 | A DNA Vaccine Encoding the VAA Gene of Vibrio anguillarum Induces a Protective Immune Response in Flounder | Vibrio anguillarum is a pathogenic bacterium that infects flounder resulting in significant losses in the aquaculture industry. The VAA protein previously identified in flounder is associated with a role in immune protection within these fish. In the present study, a recombinant DNA plasmid encoding the VAA gene of V. anguillarum was constructed and its potential as a DNA vaccine, to prevent the infection of V. anguillarum in flounder fish, investigated. We verified the expression of the VAA protein both in vitro in cell lines and in vivo in flounder fish. The protective effects of pcDNA3.1-VAA (pVAA) were analyzed by determination of the percentage of sIgM(+), CD4-1(+), CD4-2(+), CD8β(+) lymphocytes, and the production of VAA-specific antibodies in flounder following their immunization with the DNA vaccine. Histopathological changes in immune related tissues, bacterial load, and relative percentage survival rates of flounder post-challenge with V. anguillarum, were all investigated to assess the efficacy of the pVAA DNA vaccine candidate. Fish intramuscularly immunized with pVAA showed a significant increase in CD4-1(+), CD4-2(+), and CD8β(+) T lymphocytes at days 9, 11, and 14 post-vaccination, reaching peak T-cell levels at days 11 or 14 post-immunization. The percentage of sIgM(+) lymphocytes reached peak levels at weeks 4–5 post-immunization. Specific anti-V. anguillarum or anti-rVAA antibodies were induced in inoculated fish at days 28–35 post-immunization. The liver of vaccinated flounder exhibited only slight histopathological changes compared with a significant pathology observed in control immunized fish. Additionally, a lower bacterial burden in the liver, spleen, and kidney were observed in pVAA protected fish in response to bacterial challenge, compared with pcDNA3.1 vector control injected fish. Moreover, the pVAA vaccine confers a relative percentage survival of 50.00% following V. anguillarum infection. In summary, this is the first study indicating an initial induction of the T lymphocyte response, followed by B lymphocyte induction of specific antibodies as a result of DNA immunization of flounder. This signifies the important potential of pVAA as a DNA vaccine candidate for the control of V. anguillarum infection. |
3,569 | Drug screening with human SMN2 reporter identifies SMN protein stabilizers to correct SMA pathology | Spinal muscular atrophy (SMA), the leading genetic cause of infant mortality, is caused by reduced levels of functional survival motor neuron (SMN) protein. To identify therapeutic agents for SMA, we established a versatile SMN2-GFP reporter line by targeting the human SMN2 gene. We then screened a compound library and identified Z-FA-FMK as a potent candidate. Z-FA-FMK, a cysteine protease inhibitor, increased functional SMN through inhibiting the protease-mediated degradation of both full-length and exon 7–deleted forms of SMN. Further studies reveal that CAPN1, CAPN7, CTSB, and CTSL mediate the degradation of SMN proteins, providing novel targets for SMA. Notably, Z-FA-FMK mitigated mitochondriopathy and neuropathy in SMA patient–derived motor neurons and showed protective effects in SMA animal model after intracerebroventricular injection. E64d, another cysteine protease inhibitor which can pass through the blood–brain barrier, showed even more potent therapeutic effects after subcutaneous delivery to SMA mice. Taken together, we have successfully established a human SMN2 reporter for future drug discovery and identified the potential therapeutic value of cysteine protease inhibitors in treating SMA via stabilizing SMN proteins. |
3,570 | Modulating the 3’ end-DNA and the fermentation process for enhanced production and biological activity of porcine interferon-gamma | Porcine gamma interferon is a cytokine produced by activated T cells and NK cells with broad-spectrum antiviral activity and immunomodulatory function. However, pIFN-γ is a secretory protein that has a short half-life in organisms and is easily inactivated, making it difficult to apply widely in clinics. Therefore, we tried to optimize the expression of pIFN-γ in Pichia pastoris to obtain a large amount of highly active, easily purified pIFN-γ protein in vitro. Through C-terminal sequence analysis, we found a signal sequence (EKREAEAE) that was easily enzymolysed by a signal peptide enzyme, resulting in degradation and inactivation of the pIFN-γ protein. In this study, we optimized the pIFN-γ gene recombination sequence and mutated the 3' end of the pIFN-γ gene, resulting in a higher expression level and stronger biological activity, as well as a significant upregulation in the expression of the interferon-stimulated genes Mx1 and OAS1 in IPEC-J2 jejunal epithelial cells. Our data also showed that the fermentation process could significantly improve productivity. A recombinant Pichia pastoris strain with the optimized pIFN-γ gene could obtain a high yield of pIFN-γ protein, up to 9536 mg/L, after staged incubation for 0–24 h at 28°C, pH 6.0, and 50% dissolved oxygen (DO), followed by incubation for 24–72 h at 25°C, pH 6.0 and 30% DO. These data demonstrated, for the first time, that the expression level of pIFN-γ in Pichia pastoris was improved significantly by gene optimization with 3' end mutation and a fermentation process that maintained good biological activity, which is beneficial to the application of pIFN-γ in animal husbandry. |
3,571 | Dual-degree MBBS-MPH programs in Saudi Arabia: A call for implementation | Nowadays, any healthcare problem should be dealt with in a multidisciplinary approach that employs not only treating the symptoms of the problem but also its source. This simply implies the necessity to produce well-rounded medical graduates (physicians) who can competently integrate clinical knowledge/skills (for disease treatment) and public health knowledge/skills (for disease prevention). Moreover, the medical training (MD/MBBS curriculum) largely gives emphasis to the clinical skills needed to treat individual patients, whereas public health training (MPH degree) emphasizes the methods needed to improve the overall community health. Bridging the gap between patients and community is best achieved through a combined multidisciplinary training in both medicine and public health, that is, dual-degree MBBS-MPH programs are the way forward. In United States, for example, there are >80 medical schools that offer such joint MD-MPH programs, whereas there is none in Saudi Arabia. Herein, I call on higher education bodies to implement dual-degree MBBS-MPH programs in Saudi Arabia. To the best of knowledge, this is the first ever report to call for such an innovative implementation. Also, this short communication briefly sheds light on background, rationale, benefits, curriculum design, and future directions of such programs. The implications of this perspective (i.e. dual-degree MBBS-MPH programs) should not be limited to Saudi Arabia only; rather, it should be contemplated by the other medical curricula in the different countries. |
3,572 | Combination of sphingosine-1-phosphate receptor 1 (S1PR1) agonist and antiviral drug: a potential therapy against pathogenic influenza virus | The pandemic 2009 influenza A H1N1 virus is associated with significant mortality. Targeting S1PR1, which is known to modulate the immune response, provides protection against pathogenic influenza virus. The functional role and molecular mechanism of S1PR1 were analysed by generating inducible endothelial cell-specific S1PR1 knockout mice and assessing the therapeutic efficacy of the selective S1PR1 agonist CYM5442 against acute lung injury (ALI) induced by the 2009 influenza A H1N1 virus. Immune-mediated pulmonary injury is aggravated by the absence of endothelial S1PR1 and alleviated by treatment with CYM-5442, suggesting a protective function of S1PR1 signaling during H1N1 infection. S1PR1 signaling does not affect viral clearance in mice infected with influenza. Mechanistically, the MAPK and NF-kB signaling pathways are involved in the ALI mediated by S1PR1 in infected mice. Combined administration of the S1PR1 agonist CYM-5442 and the antiviral drug oseltamivir provides maximum protection from ALI. Our current study provides insight into the molecular mechanism of S1PR1 mediating the ALI induced by H1N1 infection and indicates that the combination of S1PR1 agonist with antiviral drug could potentially be used as a therapeutic remedy for future H1N1 virus pandemics. |
3,573 | Synthetic sulfonated derivatives of poly(allylamine hydrochloride) as inhibitors of human metapneumovirus | Human metapneumovirus (hMPV) is a widely distributed pathogen responsible for acute upper and lower respiratory infections of varying severity. Previously, we reported that N-sulfonated derivatives of poly(allylamine hydrochloride) (NSPAHs) efficiently inhibit replication of the influenza virus in vitro and ex vivo. Here, we show a dose dependent inhibition of hMPV infection by NSPAHs in LLC-MK2 cells. The results showed strong antiviral properties of NSPAHs. While the activity of NSPAHs is comparable to those of carrageenans, they show better physicochemical properties and may be delivered at high concentrations. The functional assays showed that tested polymers block hMPV release from infected cells and, consequently, constrain virus spread. Moreover, further studies on viruses utilizing different egress mechanisms suggest that observed antiviral effect depend on selective inhibition of viruses budding from the cell surface. |
3,574 | Endemicity and prevalence of multipartite viruses under heterogeneous between-host transmission | Multipartite viruses replicate through a puzzling evolutionary strategy. Their genome is segmented into two or more parts, and encapsidated in separate particles that appear to propagate independently. Completing the replication cycle, however, requires the full genome, so that a systemic infection of a host requires the concurrent presence of several particles. This represents an apparent evolutionary drawback of multipartitism, while its advantages remain unclear. A transition from monopartite to multipartite viral forms has been described in vitro under conditions of high multiplicity of infection, suggesting that cooperation between defective mutants is a plausible evolutionary pathway towards multipartitism. However, it is unknown how the putative advantages that multipartitism might enjoy at the microscopic level affect its epidemiology, or if an explicit advantange is needed to explain its ecological persistence. In order to disentangle which mechanisms might contribute to the rise and fixation of multipartitism, we here investigate the interaction between viral spreading dynamics and host population structure. We set up a compartmental model of the spread of a virus in its different forms and explore its epidemiology using both analytical and numerical techniques. We uncover that the impact of host contact structure on spreading dynamics entails a rich phenomenology of ecological relationships that includes cooperation, competition, and commensality. Furthermore, we find out that multipartitism might rise to fixation even in the absence of explicit microscopic advantages. Multipartitism allows the virus to colonize environments that could not be invaded by the monopartite form, while homogeneous contacts between hosts facilitate its spread. We conjecture that these features might have led to an increase in the diversity and prevalence of multipartite viral forms concomitantly with the expansion of agricultural practices. |
3,575 | Plant-derived antiviral drugs as novel hepatitis B virus inhibitors: Cell culture and molecular docking study | Despite high anti-HBV efficacies, while the nucleoside analogs (e.g., lamivudine) lead to the emergence of drug-resistance, interferons (e.g., IFN-α causes adverse side-effects. Comparatively, various natural or plant products have shown similar or even better efficacy. Hence, new antiviral strategies must focus not only on synthetic molecules but also on potential natural compounds. In this report, we have combined the in vitro cell culture and in silico molecular docking methods to assess the novel anti-HBV activity and delineate the inhibitory mechanism of selected plant-derived pure compounds of different classes. Of the tested (2.5-50 μg/ml) twelve non-cytotoxic compounds, ten (10 μg/ml) were found to maximally inhibit HBsAg production at day 5. Compared to quercetin (73%), baccatin III (71%), psoralen (67%), embelin (65%), menisdaurin (64%) and azadirachtin (62%) that showed high inhibition of HBeAg synthesis, lupeol (52%), rutin (47%), β-sitosterol (43%) and hesperidin (41%) had moderate efficacies against HBV replication. Further assessment of quercetin in combination with the highly active compounds, enhanced its anti-HBV activity up to 10%. Being the most important drug target, a 3-D structure of HBV polymerase (Pol/RT) was modeled and docked with the active compounds, including lamivudine as standard. Docking of lamivudine indicated strong interaction with the modeled HBV Pol active-site residues that formed stable complex (∆G = −5.2 kcal/mol). Similarly, all the docked antiviral compounds formed very stable complexes with HBV Pol (∆G = −6.1 to −9.3 kcal/mol). Taken together, our data suggest the anti-HBV potential of the tested natural compounds as novel viral Pol/RT inhibitors. |
3,576 | Traumatic Spinal Cord Injury: An Overview of Pathophysiology, Models and Acute Injury Mechanisms | Traumatic spinal cord injury (SCI) is a life changing neurological condition with substantial socioeconomic implications for patients and their care-givers. Recent advances in medical management of SCI has significantly improved diagnosis, stabilization, survival rate and well-being of SCI patients. However, there has been small progress on treatment options for improving the neurological outcomes of SCI patients. This incremental success mainly reflects the complexity of SCI pathophysiology and the diverse biochemical and physiological changes that occur in the injured spinal cord. Therefore, in the past few decades, considerable efforts have been made by SCI researchers to elucidate the pathophysiology of SCI and unravel the underlying cellular and molecular mechanisms of tissue degeneration and repair in the injured spinal cord. To this end, a number of preclinical animal and injury models have been developed to more closely recapitulate the primary and secondary injury processes of SCI. In this review, we will provide a comprehensive overview of the recent advances in our understanding of the pathophysiology of SCI. We will also discuss the neurological outcomes of human SCI and the available experimental model systems that have been employed to identify SCI mechanisms and develop therapeutic strategies for this condition. |
3,577 | Visual tools to assess the plausibility of algorithm-identified infectious disease clusters: an application to mumps data from the Netherlands dating from January 2009 to June 2016 | INTRODUCTION: With growing amounts of data available, identification of clusters of persons linked to each other by transmission of an infectious disease increasingly relies on automated algorithms. We propose cluster finding to be a two-step process: first, possible transmission clusters are identified using a cluster algorithm, second, the plausibility that the identified clusters represent genuine transmission clusters is evaluated. AIM: To introduce visual tools to assess automatically identified clusters. METHODS: We developed tools to visualise: (i) clusters found in dimensions of time, geographical location and genetic data; (ii) nested sub-clusters within identified clusters; (iii) intra-cluster pairwise dissimilarities per dimension; (iv) intra-cluster correlation between dimensions. We applied our tools to notified mumps cases in the Netherlands with available disease onset date (January 2009 – June 2016), geographical information (location of residence), and pathogen sequence data (n = 112). We compared identified clusters to clusters reported by the Netherlands Early Warning Committee (NEWC). RESULTS: We identified five mumps clusters. Three clusters were considered plausible. One was questionable because, in phylogenetic analysis, genetic sequences related to it segregated in two groups. One was implausible with no smaller nested clusters, high intra-cluster dissimilarities on all dimensions, and low intra-cluster correlation between dimensions. The NEWC reports concurred with our findings: the plausible/questionable clusters corresponded to reported outbreaks; the implausible cluster did not. CONCLUSION: Our tools for assessing automatically identified clusters allow outbreak investigators to rapidly spot plausible transmission clusters for mumps and other human-to-human transmissible diseases. This fast information processing potentially reduces workload. |
3,578 | A staphylococcal cyclophilin carries a single domain and unfolds via the formation of an intermediate that preserves cyclosporin A binding activity | Cyclophilin (Cyp), a peptidyl-prolyl cis-trans isomerase (PPIase), acts as a virulence factor in many bacteria including Staphylococcus aureus. The enzymatic activity of Cyp is inhibited by cyclosporin A (CsA), an immunosuppressive drug. To precisely determine the unfolding mechanism and the domain structure of Cyp, we have investigated a chimeric S. aureus Cyp (rCyp) using various probes. Our limited proteolysis and the consequent analysis of the proteolytic fragments indicate that rCyp is composed of one domain with a short flexible tail at the C-terminal end. We also show that the urea-induced unfolding of both rCyp and rCyp-CsA is completely reversible and proceeds via the synthesis of at least one stable intermediate. Both the secondary structure and the tertiary structure of each intermediate appears very similar to those of the corresponding native protein. Conversely, the hydrophobic surface areas of the intermediates are comparatively less. Further analyses reveal no loss of CsA binding activity in rCyp intermediate. The thermodynamic stability of rCyp was also significantly increased in the presence of CsA, recommending that this protein could be employed to screen new CsA derivatives in the future. |
3,579 | Clinical Scenarios of the Application of Electrical Impedance Tomography in Paediatric Intensive Care | EIT is a radiation-free functional modality that enables bedside imaging and monitoring of lung function and expansion. Clinical interest in this method has been driven by the need for bedside monitoring of the dynamics of the lungs and the effects of ventilatory manoeuvres, including changes in ventilator settings, suctioning, chest drains, positioning and physiotherapy. We aimed to describe the use of Electrical Impedance Tomography (EIT) as a clinical tool in a tertiary Paediatric Intensive Care unit. Children requiring intensive care with a variety of clinical conditions had an electrode belt with 16 electrodes wrapped around the chest, which sequentially applied a small alternating current from each electrode pair. The signal gives information on both real time, regional, global, and relative data. With the correct application, and understanding of the monitor, much clinical information can be gained, with potentially significant patient benefit. We present the clinical use of EIT in six conditions: Asthma, Ventilation weaning and expansion recoil, Sequential Lobar Collapse, Targeted Physiotherapy, Pleural Effusion assessment, and PEEP optimisation. Screenshots and analyses are offered displaying the pragmatic use of this technology. Electrical Impedance Tomography is a clinically useful tool on the Paediatric Intensive Care unit. It allows monitoring of a patient’s respiratory function in ways which are not possible through any other means. An understanding of respiratory physiology will allow use of this information to improve patient outcomes. |
3,580 | The Role of Microglia in Bacterial Meningitis: Inflammatory Response, Experimental Models and New Neuroprotective Therapeutic Strategies | Microglia have a pivotal role in the pathophysiology of bacterial meningitis. The goal of this review is to provide an overview on how microglia respond to bacterial pathogens targeting the brain, how the interplay between microglia and bacteria can be studied experimentally, and possible ways to use gained knowledge to identify novel preventive and therapeutic strategies. We discuss the dual role of microglia in disease development, the beneficial functions crucial for bacterial clearing, and the destructive properties through triggering neuroinflammation, characterized by cytokine and chemokine release which leads to leukocyte trafficking through the brain vascular endothelium and breakdown of the blood-brain barrier integrity. Due to intrinsic complexity of microglia and up until recently lack of specific markers, the study of microglial response to bacterial pathogens is challenging. New experimental models and techniques open up possibilities to accelerate progress in the field. We review existing models and discuss possibilities and limitations. Finally, we summarize recent findings where bacterial virulence factors are identified to be important for the microglial response, and how manipulation of evoked responses could be used for therapeutic or preventive purposes. Among promising approaches are: modulations of microglia phenotype switching toward anti-inflammatory and phagocytic functions, the use of non-bacterolytic antimicrobials, preventing release of bacterial components into the neural milieu and consequential amplification of immune activation, and protection of the blood-brain barrier integrity. |
3,581 | OAS1 and OAS3 negatively regulate the expression of chemokines and interferon-responsive genes in human macrophages | Upon viral infection, the 2′, 5′-oligoadenylate synthetase (OAS)-ribonuclease L (RNaseL) system works to cleave viral RNA, thereby blocking viral replication. However, it is unclear whether OAS proteins have a role in regulating gene expression. Here, we show that OAS1 and OAS3 act as negative regulators of the expression of chemokines and interferon-responsive genes in human macrophages. Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease (Cas9) technology was used to engineer human myeloid cell lines in which the OAS1 or OAS3 gene was deleted. Neither OAS1 nor OAS3 was exclusively responsible for the degradation of rRNA in macrophages stimulated with poly(I:C), a synthetic surrogate for viral double-stranded (ds)RNA. An mRNA sequencing analysis revealed that genes related to type I interferon signaling and chemokine activity were increased in OAS1(−/−) and OAS3(−/−) macrophages treated with intracellular poly(I:C). Indeed, retinoic-acid-inducible gene (RIG)-I- and interferon-induced helicase C domain-containing protein (IFIH1 or MDA5)-mediated induction of chemokines and interferon-stimulated genes was regulated by OAS3, but Toll-like receptor 3 (TLR3)- and TLR4-mediated induction of those genes was modulated by OAS1 in macrophages. However, stimulation of these cells with type I interferons had no effect on OAS1- or OAS3-mediated chemokine secretion. These data suggest that OAS1 and OAS3 negatively regulate the expression of chemokines and interferon-responsive genes in human macrophages. |
3,582 | The protonation state of an evolutionarily conserved histidine modulates domainswapping stability of FoxP1 | Forkhead box P (FoxP) proteins are members of the versatile Fox transcription factors, which control the timing and expression of multiple genes for eukaryotic cell homeostasis. Compared to other Fox proteins, they can form domain-swapped dimers through their DNA-binding –forkhead– domains, enabling spatial reorganization of distant chromosome elements by tethering two DNA molecules together. Yet, domain swapping stability and DNA binding affinity varies between different FoxP proteins. Experimental evidence suggests that the protonation state of a histidine residue conserved in all Fox proteins is responsible for pH-dependent modulation of these interactions. Here, we explore the consequences of the protonation state of another histidine (H59), only conserved within FoxM/O/P subfamilies, on folding and dimerization of the forkhead domain of human FoxP1. Dimer dissociation kinetics and equilibrium unfolding experiments demonstrate that protonation of H59 leads to destabilization of the domain-swapped dimer due to an increase in free energy difference between the monomeric and transition states. This pH–dependence is abolished when H59 is mutated to alanine. Furthermore, anisotropy measurements and molecular dynamics evidence that H59 has a direct impact in the local stability of helix H3. Altogether, our results highlight the relevance of H59 in domain swapping and folding stability of FoxP1. |
3,583 | Negative Immunomodulatory Effects of Type 2 Porcine Reproductive and Respiratory Syndrome Virus-Induced Interleukin-1 Receptor Antagonist on Porcine Innate and Adaptive Immune Functions | Impaired innate and adaptive immune responses are evidenced throughout the course of PRRSV infection. We previously reported that interleukin-1 receptor antagonist (IL-1Ra) was involved in PRRSV-induced immunosuppression during an early phase of infection. However, the exact mechanism associated with PRRSV-induced IL-1Ra immunomodulation remains unknown. To explore the immunomodulatory properties of PRRSV-induced IL-1Ra on porcine immune functions, monocyte-derived dendritic cells (MoDC) and leukocytes were cultured with type 2 PRRSV, and the immunological role of IL-1Ra was assessed by addition of anti-porcine IL-1Ra Ab. The results demonstrated that PRRSV-induced IL-1Ra reduced phagocytosis, surface expression of MHC II (SLA-DR) and CD86, as well as downregulation of IFNA and IL1 gene expression in the MoDC culture system. Interestingly, IL-1Ra secreted by the PRRSV-infected MoDC also inhibited T lymphocyte differentiation and proliferation, but not IFN-γ production. Although PRRSV-induced IL-1Ra was not directly linked to IL-10 production, it contributed to the differentiation of regulatory T lymphocytes (Treg) within the culture system. Taken together, our results demonstrated that PRRSV-induced IL-1Ra downregulates innate immune functions, T lymphocyte differentiation and proliferation, and influences collectively with IL-10 in the Treg induction. The immunomodulatory roles of IL-1Ra elucidated in this study increase our understanding of the immunobiology of PRRSV. |
3,584 | Acute Flaccid Myelitis: Something Old and Something New | Since 2014, acute flaccid myelitis (AFM), a long-recognized condition associated with polioviruses, nonpolio enteroviruses, and various other viral and nonviral causes, has been reemerging globally in epidemic form. This unanticipated reemergence is ironic, given that polioviruses, once the major causes of AFM, are now at the very threshold of global eradication and cannot therefore explain any aspect of AFM reemergence. Instead, the new AFM epidemic has been temporally associated with reemergences of nonpolio enteroviruses such as EV-D68, until recently thought to be an obscure virus of extremely low endemicity. This perspective reviews the enigmatic epidemiologic, virologic, and diagnostic aspects of epidemic AFM reemergence; examines current options for clinical management; discusses future research needs; and suggests that the AFM epidemic offers important clues to mechanisms of viral disease emergence. |
3,585 | Safety and Immunogenicity of MF59-Adjuvanted Cell Culture–Derived A/H5N1 Subunit Influenza Virus Vaccine: Dose-Finding Clinical Trials in Adults and the Elderly | BACKGROUND: A/H5N1 influenza viruses have high pandemic potential; consequently, vaccines need to be produced rapidly. MF59® adjuvant reduces the antigen required per dose, allowing for dose sparing and more rapid vaccine availability. METHODS: Two multicenter, phase II trials were conducted to evaluate the safety and immunogenicity of an MF59-adjuvanted, cell culture–derived, A/H5N1 vaccine (aH5N1c) among 979 adult (18–64 years old) and 1393 elderly (≥65 years old) subjects. Participants were equally randomized to receive 2 full-dose (7.5 μg of hemagglutinin antigen per dose) or 2 half-dose aH5N1c vaccinations 3 weeks apart. Outcomes were based on Center for Biologics Evaluation Research and Review (CBER) and Committee for Medicinal Products for Human Use (CHMP) licensure criteria (titers ≥1:40 and seroconversions on day 43). Solicited reactions and adverse events were assessed (www.clinicaltrials.gov: NCT01776541 and NCT01766921). RESULTS: CBER and CHMP criteria were met by both age groups. CBER criteria for hemagglutination titers were met for the full-dose formulation. Solicited reaction frequencies tended to be higher in the full-dose group and were of mild to moderate intensity. No vaccine-related serious adverse events occurred. CONCLUSIONS: In adult and elderly participants, the full-dose aH5N1c vaccine formulation was well tolerated and met US and European licensure criteria for pandemic vaccines. |
3,586 | Zika Virus Infection Disrupts Astrocytic Proteins Involved in Synapse Control and Axon Guidance | The first human Zika virus (ZIKV) outbreak was reported in Micronesia in 2007, followed by one in Brazil in 2015. Recent studies have reported cases in Europe, Oceania and Latin America. In 2016, ZIKV transmission was also reported in the US and the World Health Organization declared it a Public Health Emergency of International Concern. Because various neurological conditions are associated with ZIKV, such as microcephaly, Guillain-Barré syndrome, and other disorders of both the central and peripheral nervous systems, including encephalopathy, (meningo)encephalitis and myelitis, and because of the lack of reliable patient diagnosis, numerous ongoing studies seek to understand molecular mechanisms underlying ZIKV pathogenesis. Astrocytes are one of the most abundant cells in the CNS. They control axonal guidance, synaptic signaling, neurotransmitter trafficking and maintenance of neurons, and are targeted by ZIKV. In this study, we used a newly developed multiplexed aptamer-based technique (SOMAScan) to examine > 1300 human astrocyte cell proteins. We identified almost 300 astrocyte proteins significantly dysregulated by ZIKV infection that span diverse functions and signaling pathways, including protein translation, synaptic control, cell migration and differentiation. |
3,587 | The Way Forward: Potentiating Protective Immunity to Novel and Pandemic Influenza Through Engagement of Memory CD4 T Cells | Potentially pandemic strains of influenza pose an undeniable threat to human populations. Therefore, it is essential to develop better strategies to enhance vaccine design and predict parameters that identify susceptible humans. CD4 T cells are a central component of protective immunity to influenza, delivering direct effector function and potentiating responses of other lymphoid cells. Humans have highly diverse influenza-specific CD4 T-cell populations that vary in stimulation history, specificity, and functionality. These complexities constitute a formidable obstacle to predicting immune responses to pandemic strains of influenza and derivation of optimal vaccine strategies. We suggest that more precise efforts to identify and enumerate both the positive and negative contributors of immunity in the CD4 T-cell compartment will aid in both predicting susceptible hosts and in development of vaccination strategies that will poise most human subjects to respond to pandemic influenza strains with protective immune responses. |
3,588 | Predicting the Next Influenza Pandemics | Worldwide outbreaks of influenza (pandemics) are caused by influenza A viruses to which persons lack protective immune responses. Currently, we are unable to predict which influenza virus strains may cause a pandemic. In this article, we summarize some of the information that will be needed to better assess the pandemic potential of influenza viruses, and we discuss our current gaps in knowledge. |
3,589 | Making Universal Influenza Vaccines: Lessons From the 1918 Pandemic | The year 2018 marked the 100th anniversary of the deadliest event in human history. In 1918–1919, pandemic influenza spread globally and caused an estimated 50–100 million deaths associated with unexpected clinical and epidemiological features. The descendants of the 1918 virus continue to circulate as annual epidemic viruses causing significant mortality each year. The 1918 influenza pandemic serves as a benchmark for the development of universal influenza vaccines. Challenges to producing a truly universal influenza vaccine include eliciting broad protection against antigenically different influenza viruses that can prevent or significantly downregulate viral replication and reduce morbidity by preventing development of viral and secondary bacterial pneumonia. Perhaps the most important goal of such vaccines is not to prevent influenza, but to prevent influenza deaths. |
3,590 | The 1918 Influenza Pandemic: Looking Back, Looking Forward | In commemoration of the centennial of the 1918 influenza pandemic, the American Journal of Epidemiology has convened a collection of 12 articles that further illuminate the epidemiology of that pandemic and consider whether we would be more prepared if an equally deadly influenza virus were to emerge again. In the present commentary, we place these 12 articles in the context of a growing body of work on the archeo-epidemiology of past pandemics, the socioeconomic and geographic drivers of influenza mortality and natality impact, and renewed interest in immune imprinting mechanisms and the development of novel influenza vaccines. We also highlight persisting mysteries in the origins and severity of the 1918 pandemic and the need to preserve rapidly decaying information that may provide treasure troves for future generations. |
3,591 | Age-Specific Excess Mortality Patterns During the 1918–1920 Influenza Pandemic in Madrid, Spain | Although much progress has been made to uncover age-specific mortality patterns of the 1918 influenza pandemic in populations around the world, more studies in different populations are needed to make sense of the heterogeneous death impact of this pandemic. We assessed the absolute and relative magnitudes of 3 pandemic waves in the city of Madrid, Spain, between 1918 and 1920, on the basis of age-specific all-cause and respiratory excess death rates. Excess death rates were estimated using a Serfling model with a parametric bootstrapping approach to calibrate baseline death levels with quantified uncertainty. Excess all-cause and pneumonia and influenza mortality rates were estimated for different pandemic waves and age groups. The youngest and oldest persons experienced the highest excess mortality rates, and young adults faced the highest standardized mortality risk. Waves differed in strength; the peak standardized mortality risk occurred during the herald wave in spring 1918, but the highest excess rates occurred during the fall and winter of 1918/1919. Little evidence was found to support a “W”-shaped, age-specific excess mortality curve. Acquired immunity may have tempered a protracted fall wave, but recrudescent waves following the initial 2 outbreaks heightened the total pandemic mortality impact. |
3,592 | Protection against homo and hetero-subtypic influenza A virus by optimized M2e DNA vaccine | Current influenza vaccines provide hemagglutinin strain-specific protection, but rarely provide cross-protection against divergent strains. It is, therefore, particularly important to develop a universal vaccine against conserved proteins or conserved regions of the virus. In this study, we used N-terminal extracellular region of the influenza virus M2 protein (M2e) as the target antigen and constructed two optimized M2e DNA vaccines (p-tPA-p3M2e and p-p3M2e) with increased antigenic epitope density and enhanced antigen secretion. Both vaccines induced high M2e-specific humoral and cellular immune responses in the vaccinated mice. These two vaccines also conferred protection against a lethal infection of homo-subtypic H1N1 virus, with p-tPA-p3M2e being the most effective. In addition, p-tPA-p3M2e also showed cross-protection against different subtypes of the influenza virus (H9N2, H6N6, and H10N8) at varying rates (80%, 40%, and 20%, respectively). After passive immunization, M2e DNA vaccine-induced antibodies in the sera provided complete protection against homologous virus challenge. An analysis of the mechanism underlying this immunization-mediated protection indicates that M2e-specific IgG and T-cell immune responses may play critical roles in the prevention of infection and viral clearance. Taken together, our results indicate that this optimized M2e DNA vaccine is a promising candidate for the development of a universal, broad-spectrum influenza virus vaccine. |
3,593 | Trajectories of School Recovery After a Natural Disaster: Risk and Protective Factors | Disasters may have significant and lasting impacts on educational programs and academic achievement, yet the examination of differing patterns of school recovery after disasters is understudied. This paper focused on two aims: (i) identification of school academic recovery trajectories; and (ii) examination of potential risk factors associated with these trajectories. We used latent class growth analysis to identify school academic recovery trajectories for a cohort of 462 Texas public schools that were in the path of Hurricane Ike in 2008. Using Texas Assessment of Knowledge and Skills (TAKS) data from 2005 to 2011, we found that attendance and percent of economically disadvantaged youth emerged as significant risk factors for two identified academic recovery trajectories (High‐Stable and Low‐Interrupted). Higher levels of economically disadvantaged youth were associated with lower likelihood of falling in the High‐Stable trajectory, relative to the Low‐Interrupted trajectory. Higher levels of attendance were associated with higher likelihood of membership in the High‐Stable trajectory, relative to the Low‐Interrupted trajectory. These findings are consistent with the notion that disasters do not affect all people or communities equally. Findings highlight the need for policy initiatives that focus on low performing schools, as these schools are at highest risk for adverse outcomes post‐disaster. |
3,594 | Misdiagnosis of scrub typhus complicated by hemophagocytic syndrome | BACKGROUND: This study sought to analyze the cases of clinical misdiagnosis of scrub typhus complicated by hemophagocytic syndrome. METHODS: We retrospectively reviewed the medical records for diagnoses, clinical course, chest X-ray findings, laboratory data, and antibiotic therapy. RESULTS: All nine patients were misdiagnosed at the outpatient department between 07/2009 and 07/2017. They were diagnosed with septicemia and hemophagocytic syndrome, sepsis and hemophagocytic syndrome, severe infection, hepatitis and hemophagocytic syndrome, or upper respiratory tract infection. Among the nine patients, hepatic function examination showed decreased albumin and elevated C-reactive protein levels in all patients; alanine aminotransferase was increased and platelets were decreased in eight patients. Weil-Felix reaction was positive in three of nine patients. Indirect immunofluorescence demonstrated positive IgM antibody and EB virus-IgM in all nine patients; Mycoplasma pneumoniae antibody was positive in seven patients. All nine patients underwent chest computed tomography; no abnormality was found in two patients. Patch shadow with increased density was found in seven patients, including four patients with right pleural effusion and two with bilateral pleural effusion. Bone marrow biopsy was performed in all nine patients and hemophagocytic cells were seen. The nine misdiagnosed cases were given multiple broad-spectrum antibiotics either successively or concomitantly before and after admission, but no effective antibiotics against Orientis tsutsugamushi were applied. After diagnosis was corrected to scrub typhus, five patients were switched to chloramphenicol and dexamethasone, two patients were given azithromycin and dexamethasone, and two patients were treated with chloramphenicol. Body temperature returned to normal within 2–3 days and the children were quickly relieved from their condition. CONCLUSION: Hemophagocytic syndrome may be the presenting clinical feature of scrub typhus and initially mask the disease. Initial misdiagnosis is common and includes septicemia and hemophagocytic syndrome. The eschar is a useful diagnostic clue and febrile patients without any localizing signs should be thoroughly examined for its presence. |
3,595 | An OpenMP-based tool for finding longest common subsequence in bioinformatics | OBJECTIVE: Finding the longest common subsequence (LCS) among sequences is NP-hard. This is an important problem in bioinformatics for DNA sequence alignment and pattern discovery. In this research, we propose new CPU-based parallel implementations that can provide significant advantages in terms of execution times, monetary cost, and pervasiveness in finding LCS of DNA sequences in an environment where Graphics Processing Units are not available. For general purpose use, we also make the OpenMP-based tool publicly available to end users. RESULT: In this study, we develop three novel parallel versions of the LCS algorithm on: (i) distributed memory machine using message passing interface (MPI); (ii) shared memory machine using OpenMP, and (iii) hybrid platform that utilizes both distributed and shared memory using MPI-OpenMP. The experimental results with both simulated and real DNA sequence data show that the shared memory OpenMP implementation provides at least two-times absolute speedup than the best sequential version of the algorithm and a relative speedup of almost 7. We provide a detailed comparison of the execution times among the implementations on different platforms with different versions of the algorithm. We also show that removing branch conditions negatively affects the performance of the CPU-based parallel algorithm on OpenMP platform. |
3,596 | The Long Pentraxin PTX3 as a Link Between Innate Immunity, Tissue Remodeling, and Cancer | The innate immune system comprises a cellular and a humoral arm. Humoral pattern recognition molecules include complement components, collectins, ficolins, and pentraxins. These molecules are involved in innate immune responses by recognizing microbial moieties and damaged tissues, activating complement, exerting opsonic activity and facilitating phagocytosis, and regulating inflammation. The long pentraxin PTX3 is a prototypic humoral pattern recognition molecule that, in addition to providing defense against infectious agents, plays several functions in tissue repair and regulation of cancer-related inflammation. Characterization of the PTX3 molecular structure and biochemical properties, and insights into its interactome and multiple roles in tissue damage and remodeling support the view that microbial and matrix recognition are evolutionarily conserved functions of humoral innate immunity molecules. |
3,597 | Characterization and bioactivity of self-assembled anti-angiogenic chondroitin sulfate-ES2-AF nanoparticle conjugate | BACKGROUND: In the past few years, significant progress has been made in inhibiting neovascularization at the tumor site, cutting off the nutrient supply of the tumor, and inhibiting tumor growth and metastasis. However, many proteins/peptides have the disadvantage of poor stability, short half-life, and uncertain targeting ability. Chemical modification can be used to overcome these disadvantages; many polyethylene glycol-modified proteins/peptides have been approved by US FDA. The purpose of this study was to obtain a novel anti-angiogenic chondroitin sulfate (CS)-peptide nanoparticle conjugate with efficient anti-neovascularization and tumor targeting ability and an acceptable half-life. MATERIALS AND METHODS: The CS-ES2-AF nanoparticle conjugate was synthesized and characterized using (1)H-nuclear magnetic resonance spectroscopy, transmission electron microscopy, and particle size and zeta potential analyzer. The anti-angiogenic ability was studied using MTT, migration, tube formation, and chick chorioallantoic membrane assays. The targeting ability of CS-ES2-AF was studied by ELISA, surface plasmon resonance, and bioimaging. The pharmacokinetics was also studied. RESULTS: The CS-ES2-AF could self-assemble into stable nanoparticles in aqueous solution, which significantly enhances its anti-neovascularization activity, tumor targeting more explicit, and prolongs its half-life. CONCLUSION: CS is an effective protein/peptide modifier, and CS-ES2-AF displayed good potential in tumor targeting therapy. |
3,598 | Zika Outbreak Emergency Preparedness and Response of Malaysian Private Healthcare Professionals: Are They Ready? | Zika virus has been declared as a public health emergency of international concern. The Center for Disease Control and Prevention has issued guidelines reminding healthcare workers about the importance of taking steps to prevent the spread of Zika virus, how to test and isolate patients suspected of carrying the Zika virus, and how to protect themselves from infection. Therefore, it is of utmost importance for healthcare professionals to be fully aware of Zika virus preparedness, and response measures should an outbreak occur in Malaysia in order to quickly and efficiently contain the outbreak, ensure the safety of individual or healthcare personnel safety, as well as to prevent further spreading of the disease. This research aims to show how prepared Malaysian healthcare professionals are against Zika virus and how well can they respond during an outbreak. In total, 504 healthcare professionals (128 general practitioners, 215 community pharmacists, 161 nurses) from private health clinics were the target population of the four states of Malaysia where Zika cases suspected. The sample size of each category was calculated by using a formula for estimating the population proportion. An additional 10% of the calculated sample size was added to compensate the non-response rate. The Center For Disease Control and Prevention and World Health Organisation provided a checklist to assess how prepared healthcare professionals are for an Zika outbreak. This checklist was modified to a questionnaire in order to assess health care professionals’ preparedness and response to the Zika outbreak. Community pharmacists are still lacking in their preparedness and perceived response to the Zika outbreak compared to the general practitioners in the private sector. Hence community pharmacists should attend training given by the Ministry of Health Malaysia as a continuing education, which may help them to respond during a Zika outbreak. |
3,599 | Rabies-based vaccine induces potent immune responses against Nipah virus | Nipah Virus (NiV) is a re-emerging zoonotic pathogen in the genus Henipavirus of the Paramyxoviridae family of viruses. NiV is endemic to Bangladesh and Malaysia and is highly fatal to both livestock and humans (human case fatality rate = 74.5%). Currently, there is no approved vaccine against NiV on the market. The goal of this study was to use a recombinant RABV vector expressing NiV glycoprotein (NiV G) to develop a bivalent candidate vaccine against NiV disease and rabies virus (RABV) disease, which is also a significant health burden in the regions where NiV is endemic. The rabies vector is a well-established vaccine strain that lacks neurovirulence and can stably expresses foreign antigens that are immunogenic in various animal models. Mice inoculated intranasally with the live recombinant RABV/NiV vaccine (NIPARAB) showed no signs of disease. To test the immunogenicity of the vaccine candidate, groups of C57BL/6 mice were immunized intramuscularly with a single dose of live vaccine particles or two doses of chemically inactivated viral particles. Both vaccination groups showed NiV G-specific seroconversion, and the inactivated (INAC) vaccine group yielded higher titers of NiV G-specific antibodies. Furthermore, cross-reactivity of NiV G-specific immune sera against Hendra virus (HeV), was confirmed by immunofluorescence (IF) and indirect ELISA against soluble recombinant HeV glycoprotein (HeV G). Both live and killed vaccines induced neutralizing antibodies. These results indicate that NIPARAB may be used as a killed virus vaccine to protect humans against NiV and RABV, and possibly as a preventative measure against HeV as well. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.