abstract
stringlengths 0
122k
|
|---|
BACKGROUND: Increased vascular permeability is a key feature in the pathophysiology of sepsis and the development of organ failure. Shedding of the endothelial glycocalyx is increasingly being recognized as an important pathophysiological mechanism but at present it is unclear if glypicans contribute to this response. We hypothesized that plasma levels of glypicans (GPC) are elevated in patients with sepsis. METHODS: Plasma GPC 1–6 levels were measured by ELISA in 10 patients with sepsis and 10 healthy controls as an initial screening. Plasma GPC 1, 3, and 4 were further measured in a cohort of 184 patients with a clinically confirmed infection. Patients were divided into groups of those who had sepsis and those who had an infection without organ failure. To determine whether plasma glypicans could predict the development of organ failure, patients were further subdivided to those who had organ failure at enrolment and those who developed it after enrollment. The association of plasma GPC 1, 3, and 4 with organ failure and with various markers of inflammation, disease severity, and glycocalyx shedding was investigated. RESULTS: In the pilot study, only GPC 1, 3, and 4 were detectable in the plasma of sepsis patients. In the larger cohort, GPC 1, 3, and 4 levels were significantly higher (p < 0.001) in patients with sepsis than in those with infection without organ failure. GPC 1, 3, and 4 were significantly positively correlated with plasma levels of the disease severity markers C-reactive protein, lactate, procalcitonin, and heparin binding protein, and with the marker of glycocalyx degradation syndecan 1. They were significantly negatively correlated with plasma levels of the glycocalyx-protective factors apolipoprotein M and sphingosine-1-phosphate. CONCLUSIONS: We show that GPC 1, 3, and 4 are elevated in plasma of patients with sepsis and correlate with markers of disease severity, systemic inflammation, and glycocalyx damage. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s40635-018-0216-z) contains supplementary material, which is available to authorized users. |
The Integrated Microbial Genome/Virus (IMG/VR) system v.2.0 (https://img.jgi.doe.gov/vr/) is the largest publicly available data management and analysis platform dedicated to viral genomics. Since the last report published in the 2016, NAR Database Issue, the data has tripled in size and currently contains genomes of 8389 cultivated reference viruses, 12 498 previously published curated prophages derived from cultivated microbial isolates, and 735 112 viral genomic fragments computationally predicted from assembled shotgun metagenomes. Nearly 60% of the viral genomes and genome fragments are clustered into 110 384 viral Operational Taxonomic Units (vOTUs) with two or more members. To improve data quality and predictions of host specificity, IMG/VR v.2.0 now separates prokaryotic and eukaryotic viruses, utilizes known prophage sequences to improve taxonomic assignments, and provides viral genome quality scores based on the estimated genome completeness. New features also include enhanced BLAST search capabilities for external queries. Finally, geographic map visualization to locate user-selected viral genomes or genome fragments has been implemented and download options have been extended. All of these features make IMG/VR v.2.0 a key resource for the study of viruses. |
BACKGROUND: Human adenovirus type 3 (HAdV-3) and 7 (HAdV-7) cause significant morbidity and develop severe complications and long-term pulmonary sequelae in children. However, epidemiologic reports have suggested that nearly all highly severe or fatal adenoviral diseases in children are associated with HAdV-7 rather than HAdV-3. Here, we conduct in-depth investigations to confirm and extend these findings through a comprehensive series of assays in vitro and in vivo as well as clinical correlates. METHODS: A total of 8248 nasopharyngeal aspirate (NPA) samples were collected from hospitalized children with acute respiratory infections in Children’s Hospital of Chongqing Medical University from June 2009 to May 2015. Among 289 samples that tested positive for HAdVs, clinical data of 258 cases of HAdV-3 (127) and HAdV-7 (131) infections were analyzed. All HAdV-positive samples were classified by sequencing the hexon and fiber genes, and compared with clinical data and virological assays. We also performed in vitro assays of virus quantification, viral growth kinetics, competitive fitness, cytotoxicity and C3a assay of the two strains. Mouse adenovirus model was used to evaluate acute inflammatory responses. RESULTS: Clinical characteristics revealed that HAdV-7 infection caused more severe pneumonia, toxic encephalopathy, respiratory failure, longer mean hospitalization, significantly lower white blood cell (WBC) and platelet counts, compared to those of HAdV-3. In cell culture, HAdV-7 replicated at a higher level than HAdV-3, and viral fitness showed significant differences as well. HAdV-7 also exhibited higher C3a production and cytotoxic effects, and HAdV-7-infected mice showed aggravated pathology and higher pulmonary virus loads, compared to HAdV-3-infected mice. Macrophages in BALF remained markedly high during infection, with concomitant increase in pro-inflammatory cytokines (TNF-α, IL-1β, IFN-γ, and IL-6), compared HAdV-3 infection. CONCLUSIONS: These results document that HAdV-7 replicates more robustly than HAdV-3, and promotes an exacerbated cytokine response, causing a more severe airway inflammation. The findings merit further mechanistic studies that offer the pediatricians an informed decision to proceed with early diagnosis and treatment of HAdV-7 infection. |
Apoptosis is a form of cell death by which the body maintains the homeostasis of the internal environment. Apoptosis is an initiative cell death process that is controlled by genes and is mainly divided into endogenous pathways (mitochondrial pathway), exogenous pathways (death receptor pathway), and apoptotic pathways induced by endoplasmic reticulum (ER) stress. The homeostasis imbalance in ER results in ER stress. Under specific conditions, ER stress can be beneficial to the body; however, if ER protein homeostasis is not restored, the prolonged activation of the unfolded protein response may initiate apoptotic cell death via the up-regulation of the C/EBP homologous protein (CHOP). CHOP plays an important role in ER stress-induced apoptosis and this review focuses on its multifunctional roles in that process, as well as its role in apoptosis during microbial infection. We summarize the upstream and downstream pathways of CHOP in ER stress induced apoptosis. We also focus on the newest discoveries in the functions of CHOP-induced apoptosis during microbial infection, including DNA and RNA viruses and some species of bacteria. Understanding how CHOP functions during microbial infection will assist with the development of antimicrobial therapies. |
Eight novel N′-(2-oxoindolin-3-ylidene)-2-propylpentane hydrazide-hydrazone derivatives 4a–h were synthesized and fully characterized by IR, NMR ((1)H-NMR and (13)C-NMR), elemental analysis, and X-ray crystallography. The cyto-toxicity and in vitro anti-cancer evaluation of the prepared compounds have been assessed against two different human tumour cell lines including human liver (HepG2) and leukaemia (Jurkat), as well as in normal cell lines derived from human embryonic kidney (HEK293) using MTT assay. The compounds 3e, 3f, 4a, 4c, and 4e revealed promising anti-cancer activities in tested human tumour cells lines (IC(50) values between 3 and 7 μM) as compared to the known anti-cancer drug 5-Fluorouracil (IC(50) 32–50 μM). Among the tested compounds, 4a showed specificity against leukaemia (Jurkat) cells, with an IC(50) value of 3.14 μM, but this compound was inactive in liver cancer and normal cell lines. |
The functionalisation of microbeads with oligonucleotides has become an indispensable technique for high-throughput aptamer selection in SELEX protocols. In addition to simplifying the separation of binding and non-binding aptamer candidates, microbeads have facilitated the integration of other technologies such as emulsion PCR (ePCR) and Fluorescence Activated Cell Sorting (FACS) to high-throughput selection techniques. Within these systems, monoclonal aptamer microbeads can be individually generated and assayed to assess aptamer candidate fitness thereby helping eliminate stochastic effects which are common to classical SELEX techniques. Such techniques have given rise to aptamers with 1000 times greater binding affinities when compared to traditional SELEX. Another emerging technique is Fluorescence Activated Droplet Sorting (FADS) whereby selection does not rely on binding capture allowing evolution of a greater diversity of aptamer properties such as fluorescence or enzymatic activity. Within this review we explore examples and applications of oligonucleotide functionalised microbeads in aptamer selection and reflect upon new opportunities arising for aptamer science. |
Acute lung injury (ALI) affects over 10% of patients hospitalised in critical care, with acute respiratory distress syndrome (ARDS) being the most severe form of ALI and having a mortality rate in the region of 40%. There has been slow but incremental progress in identification of biomarkers that contribute to the pathophysiology of ARDS, have utility in diagnosis and monitoring, and that are potential therapeutic targets (Calfee CS, Delucchi K, Parsons PE, Thompson BT, Ware LB, Matthay MA, Thompson T, Ware LB, Matthay MA, Lancet Respir Med 2014, 2:611–-620). However, a major issue is that ARDS is such a heterogeneous, multi-factorial, end-stage condition that the strategies for “lumping and splitting” are critical (Prescott HC, Calfee CS, Thompson BT, Angus DC, Liu VX, Am J Respir Crit Care Med 2016, 194:147–-155). Nevertheless, sequencing of the human genome, the availability of improved methods for analysis of transcription to mRNA (gene expression), and development of sensitive immunoassays has allowed the application of network biology to ARDS, with these biomarkers offering potential for personalised or precision medicine (Sweeney TE, Khatri P, Toward precision medicine Crit Care Med; 2017 45:934-939). Biomarker panels have potential applications in molecular phenotyping for identifying patients at risk of developing ARDS, diagnosis of ARDS, risk stratification and monitoring. Two subphenotypes of ARDS have been identified on the basis of blood biomarkers: hypo-inflammatory and hyper-inflammatory. The hyper-inflammatory subphenotype is associated with shock, metabolic acidosis and worst clinical outcomes. Biomarkers of particular interest have included interleukins (IL-6 and IL-8), interferon gamma (IFN-γ), surfactant proteins (SPD and SPB), von Willebrand factor antigen, angiopoietin 1/2 and plasminogen activator inhibitor-1 (PAI-1). In terms of gene expression (mRNA) in blood there have been found to be increases in neutrophil-related genes in sepsis-induced and influenza-induced ARDS, but whole blood expression does not give a robust diagnostic test for ARDS. Despite improvements in management of ARDS on the critical care unit, this complex disease continues to be a major life-threatening event. Clinical trials of β(2)-agonists, statins, surfactants and keratinocyte growth factor (KGF) have been disappointing. In addition, monoclonal antibodies (anti-TNF) and TNFR fusion protein have also been unconvincing. However, there have been major advances in methods of mechanical ventilation, a neuromuscular blocker (cisatracurium besilate) has shown some benefit, and stem cell therapy is being developed. In the future, by understanding the role of biomarkers in the pathophysiology of ARDS and lung injury, it is hoped that this will provide rational therapeutic targets and ultimately improve clinical care (Seymour CW, Gomez H, Chang CH, Clermont G, Kellum JA, Kennedy J, Yende S, Angus DC, Crit Care 2017, 21:257). |
Interferon-induced transmembrane protein 3 (IFITM3) is a potent antiviral protein that enhances cellular resistance to a variety of pathogens, including influenza virus. Classically defined as an interferon-stimulated gene, expression of IFITM3 on cells is rapidly up-regulated in response to type I and II interferon. Here we found that IFITM3 is rapidly up-regulated by T cells following their activation and this occurred independently of type I and II interferon and the interferon regulatory factors 3 and 7. Up-regulation of IFITM3 on effector T cells protected these cells from virus infection and imparted a survival advantage at sites of virus infection. Our results show that IFITM3 expression on effector T cells is crucial for these cells to mediate their effector function and highlights an interferon independent pathway for the induction of IFITM3 which, if targeted, could be an effective approach to harness the activity of IFITM3 for infection prevention. |
Many viruses interface with the autophagy pathway, a highly conserved process for recycling cellular components. For three viral infections in which autophagy constituents are proviral (poliovirus, dengue, and Zika), we developed a panel of knockouts (KOs) of autophagy-related genes to test which components of the canonical pathway are utilized. We discovered that each virus uses a distinct set of initiation components; however, all three viruses utilize autophagy-related gene 9 (ATG9), a lipid scavenging protein, and LC3 (light-chain 3), which is involved in membrane curvature. These results show that viruses use noncanonical routes for membrane sculpting and LC3 recruitment. By measuring viral RNA abundance, we also found that poliovirus utilizes these autophagy components for intracellular growth, while dengue and Zika virus only use autophagy components for post-RNA replication processes. Comparing how RNA viruses manipulate the autophagy pathway reveals new noncanonical autophagy routes, explains the exacerbation of disease by starvation, and uncovers common targets for antiviral drugs. |
BACKGROUND: The 2009 influenza pandemic was caused by the A/H1N1pdm09 virus, which was subsequently included in the seasonal vaccine, up to 2016/2017, as the A/H1N1 strain. This provided a unique opportunity to investigate the antibody response to H1N1pdm09 over time. METHODS: Healthcare workers (HCWs) were immunized with the AS03-adjuvanted H1N1pdm09 vaccine in 2009 (N = 250), and subsequently vaccinated with seasonal vaccines containing H1N1pdm09 for 4 seasons (repeated group), <4 seasons (occasional group), or no seasons (single group). Blood samples were collected pre and at 21 days and 3, 6, and 12 months after each vaccination, or annually (pre-season) from 2010 in the single group. The H1N1pdm09-specific antibodies were measured by the hemagglutination inhibition (HI) assay. RESULTS: Pandemic vaccination robustly induced HI antibodies that persisted above the 50% protective threshold (HI titers ≥ 40) over 12 months post-vaccination. Previous seasonal vaccination and the duration of adverse events after the pandemic vaccination influenced the decision to vaccinate in subsequent seasons. During 2010/2011–2013/2014, antibodies were boosted after each seasonal vaccination, although no significant difference was observed between the repeated and occasional groups. In the single group without seasonal vaccination, 32% of HCWs seroconverted (≥4-fold increase in HI titers) during the 4 subsequent years, most of whom had HI titers <40 prior to seroconversion. When excluding these seroconverted HCWs, HI titers gradually declined from 12 to 60 months post–pandemic vaccination. CONCLUSIONS: Pandemic vaccination elicited durable antibodies, supporting the incorporation of adjuvant. Our findings support the current recommendation of annual influenza vaccination in HCWs. CLINICAL TRIALS REGISTRATION: NCT01003288. |
To replicate and disseminate, viruses need to manipulate and modify the cellular machinery for their own benefit. We are interested in translation, which is one of the key steps of gene expression and viruses that have developed several strategies to hijack the ribosomal complex. The type 1 human immunodeficiency virus is a good paradigm to understand the great diversity of translational control. Indeed, scanning, leaky scanning, internal ribosome entry sites, and adenosine methylation are used by ribosomes to translate spliced and unspliced HIV-1 mRNAs, and some require specific cellular factors, such as the DDX3 helicase, that mediate mRNA export and translation. In addition, some viral and cellular proteins, including the HIV-1 Tat protein, also regulate protein synthesis through targeting the protein kinase PKR, which once activated, is able to phosphorylate the eukaryotic translation initiation factor eIF2α, which results in the inhibition of cellular mRNAs translation. Finally, the infection alters the integrity of several cellular proteins, including initiation factors, that directly or indirectly regulates translation events. In this review, we will provide a global overview of the current situation of how the HIV-1 mRNAs interact with the host cellular environment to produce viral proteins. |
BACKGROUND: Epidemiological surveillance of HIV infection in Japan involves two technical problems for directly applying a classical backcalculation method, i.e., (i) all AIDS cases are not counted over time and (ii) people diagnosed with HIV have received antiretroviral therapy, extending the incubation period. The present study aimed to address these issues and estimate the HIV incidence and the proportion of diagnosed HIV infections, using a simple statistical model. METHODS: From among Japanese nationals, yearly incidence data of HIV diagnoses and patients with AIDS who had not previously been diagnosed as HIV positive, from 1985 to 2017, were analyzed. Using the McKendrick partial differential equation, general convolution-like equations were derived, allowing estimation of the HIV incidence and the time-dependent rate of diagnosis. A likelihood-based approach was used to obtain parameter estimates. RESULTS: Assuming that the median incubation period was 10.0 years, the cumulative number of HIV infections was estimated to be 29,613 (95% confidence interval (CI): 29,059, 30,167) by the end of 2017, and the proportion of diagnosed HIV infections was estimated at 80.3% (95% CI [78.7%–82.0%]). Allowing the median incubation period to range from 7.5 to 12.3 years, the estimate of the proportion diagnosed can vary from 77% to 84%. DISCUSSION: The proportion of diagnosed HIV infections appears to have not yet reached 90% among Japanese nationals. Compared with the peak incidence from 2005–2008, new HIV infections have clearly been in a declining trend; however, there are still more than 1,000 new HIV infections per year in Japan. To increase the diagnosed proportion of HIV infections, it is critical to identify people who have difficulty accessing consultation, testing, and care, and to explore heterogeneous patterns of infection. |
While active immunization elicits a lasting immune response by the body, passive immunotherapy transiently equips the body with exogenously generated immunological effectors in the form of either target-specific antibodies or lymphocytes functionalized with target-specific receptors. In either case, administration or expression of recombinant proteins plays a fundamental role. mRNA prepared by in vitro transcription (IVT) is increasingly appreciated as a drug substance for delivery of recombinant proteins. With its biological role as transient carrier of genetic information translated into protein in the cytoplasm, therapeutic application of mRNA combines several advantages. For example, compared to transfected DNA, mRNA harbors inherent safety features. It is not associated with the risk of inducing genomic changes and potential adverse effects are only temporary due to its transient nature. Compared to the administration of recombinant proteins produced in bioreactors, mRNA allows supplying proteins that are difficult to manufacture and offers extended pharmacokinetics for short-lived proteins. Based on great progress in understanding and manipulating mRNA properties, efficacy data in various models have now demonstrated that IVT mRNA constitutes a potent and flexible platform technology. Starting with an introduction into passive immunotherapy, this review summarizes the current status of IVT mRNA technology and its application to such immunological interventions. |
Chikungunya virus (CHIKV) is a reemerging global health threat that produces debilitating arthritis in people. Like other RNA viruses with high mutation rates, CHIKV produces populations of genetically diverse genomes within a host. While several known CHIKV mutations influence disease severity in vertebrates and transmission by mosquitoes, the role of intrahost diversity in chikungunya arthritic disease has not been studied. In this study, high- and low-fidelity CHIKV variants, previously characterized by altered in vitro population mutation frequencies, were used to evaluate how intrahost diversity influences clinical disease, CHIKV replication, and antibody neutralization in immunocompetent adult mice inoculated in the rear footpads. Both high- and low-fidelity mutations were hypothesized to attenuate CHIKV arthritic disease, replication, and neutralizing antibody levels compared to wild-type (WT) CHIKV. Unexpectedly, high-fidelity mutants elicited more severe arthritic disease than the WT despite comparable CHIKV replication, whereas a low-fidelity mutant produced attenuated disease and replication. Serum antibody developed against both high- and low-fidelity CHIKV exhibited reduced neutralization of WT CHIKV. Using next-generation sequencing (NGS), the high-fidelity mutations were demonstrated to be genetically stable but produced more genetically diverse populations than WT CHIKV in mice. This enhanced diversification was subsequently reproduced after serial in vitro passage. The NGS results contrast with previously reported population diversities for fidelity variants, which focused mainly on part of the E1 gene, and highlight the need for direct measurements of mutation rates to clarify CHIKV fidelity phenotypes. IMPORTANCE CHIKV is a reemerging global health threat that elicits debilitating arthritis in humans. There are currently no commercially available CHIKV vaccines. Like other RNA viruses, CHIKV has a high mutation rate and is capable of rapid intrahost diversification during an infection. In other RNA viruses, virus population diversity associates with disease progression; however, potential impacts of intrahost viral diversity on CHIKV arthritic disease have not been studied. Using previously characterized CHIKV fidelity variants, we addressed whether CHIKV population diversity influences the severity of arthritis and host antibody response in an arthritic mouse model. Our findings show that CHIKV populations with greater genetic diversity can cause more severe disease and stimulate antibody responses with reduced neutralization of low-diversity virus populations in vitro. The discordant high-fidelity phenotypes in this study highlight the complexity of inferring replication fidelity indirectly from population diversity. |
Memory B cells that are generated during an infection or following vaccination act as sentinels to guard against future infections. Upon repeat antigen exposure memory B cells differentiate into new antibody-secreting plasma cells to provide rapid and sustained protection. Some pathogens evade or suppress the humoral immune system, or induce memory B cells with a diminished ability to differentiate into new plasma cells. This leaves the host vulnerable to chronic or recurrent infections. Single cell approaches coupled with next generation antibody gene sequencing facilitate a detailed analysis of the pathogen-specific memory B cell repertoire. Monoclonal antibodies that are generated from antibody gene sequences allow a functional analysis of the repertoire. This review discusses what has been learned thus far from analysis of diverse pathogen-specific memory B cell compartments and describes major differences in their repertoires. Such information may illuminate ways to advance the goal of improving vaccine and therapeutic antibody design. |
BACKGROUND: The acute respiratory distress syndrome (ARDS) is characterized by the acute onset of hypoxemia and bilateral lung infiltrates in response to an inciting event, and is associated with high morbidity and mortality. Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are at increased risk for ARDS. We hypothesized that HSCT patients with ARDS would have a unique transcriptomic profile identifiable in peripheral blood compared to those that did not undergo HSCT. METHODS: We isolated RNA from banked peripheral blood samples from a biorepository of critically ill ICU patients. RNA-Seq was performed on 11 patients with ARDS (5 that had undergone HSCT and 6 that had not) and 12 patients with sepsis without ARDS (5 that that had undergone HCST and 7 that had not). RESULTS: We identified 687 differentially expressed genes between ARDS and ARDS-HSCT (adjusted p-value < 0.01), including IFI44L, OAS3, LY6E, and SPATS2L that had increased expression in ARDS vs. ARDS-HSCT; these genes were not differentially expressed in sepsis vs sepsis-HSCT. Gene ontology enrichment analysis revealed that many differentially expressed genes were related to response to type I interferon. CONCLUSIONS: Our findings reveal significant differences in whole blood transcriptomic profiles of patients with non-HSCT ARDS compared to ARDS-HSCT patients and point toward different immune responses underlying ARDS and ARDS-HSCT that contribute to lung injury. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12931-019-0981-6) contains supplementary material, which is available to authorized users. |
Basal cell carcinoma (BCC) is the most common type of human skin cancer, which is driven by the aberrant activation of Hedgehog signaling. Previous evidence indicated that sex determining region Y-box 2 (SOX2) is associated with the tumor metastasis. However, the expression and role of SOX2 in BCC remain unknown. Therefore, the aim of the current study was to analyze the possible mechanism of SOX2 in the progression of BCC. The levels of SOX2 in BCC cells were detected by reverse transcription-quantitative polymerase chain reaction. Transwell assays were also used to determine the migration and invasion of BCC cells. Immunoblotting and immunofluorescence were used for analyzing the role of SOX2 knockdown in the serine-arginine protein kinase 1 (SRPK1)-mediated phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signaling pathway in BCC cells. The results demonstrated that SOX2 is overexpressed in BCC tissues and cells. In addition, SOX2 knockdown inhibited the migration and invasion of BCC cells, and the epithelial-mesenchymal transition (EMT) progress of BCC cells. It was also observed that SOX2 knockdown decreased SRPK1 expression, which further led to the downregulation of PI3K and AKT expression levels in BCC cells. Furthermore, SRPK1 transfection or PI3K/AKT pathway activation abolished the inhibitory effects of SOX2 knockdown on the migration, invasion and EMT progress of BCC cells. In conclusion, these results indicated that SOX2 may potentially serve as a target for BCC therapy by targeting the SRPK1-mediated PI3K/AKT signaling pathway. |
Recent evidence has confirmed that a mutation of the isocitrate dehydrogenase (IDH) gene occurs early in gliomagenesis and contributes to suppressed immunity. The present study aimed to determine the candidate genes associated with IDH mutation status that could serve as biomarkers of immune suppression for improved prognosis prediction. Clinical information and RNA-seq gene expression data were collected for 932 glioma samples from the CGGA and TCGA databases, and differentially expressed genes in both lower-grade glioma (LGG) and glioblastoma (GBM) samples were identified according to IDH mutation status. Only one gene, interferon-stimulated exonuclease gene 20 (ISG20), with reduced expression in IDH mutant tumors, demonstrated significant prognostic value. ISG20 expression level significantly increased with increasing tumor grade, and its high expression was associated with a poor clinical outcome. Moreover, increased ISG20 expression was associated with increased infiltration of monocyte-derived macrophages and neutrophils, and suppressed adaptive immune response. ISG20 expression was also positively correlated with PD-1, PD-L1, and CTLA4 expression, along with the levels of several chemokines. We conclude that ISG20 is a useful biomarker to identify IDH-mediated immune processes in glioma and may serve as a potential therapeutic target. |
Post-translational modification of host and viral proteins by ubiquitin (Ub) and Ub-like proteins, such as interferon stimulated gene product 15 (ISG15), plays a key role in response to infection. Viruses have been increasingly identified that contain proteases possessing deubiquitinase (DUB) and/or deISGylase functions. This includes viruses in the Nairoviridae family that encode a viral homologue of the ovarian tumor protease (vOTU). vOTU activity was recently demonstrated to be critical for replication of the often-fatal Crimean-Congo hemorrhagic fever virus, with DUB activity suppressing the type I interferon responses and deISGylase activity broadly removing ISG15 conjugated proteins. There are currently about 40 known nairoviruses classified into fourteen species. Recent genomic characterization has revealed a high degree of diversity, with vOTUs showing less than 25% amino acids identities within the family. Previous investigations have been limited to only a few closely related nairoviruses, leaving it unclear what impact this diversity has on vOTU function. To probe the effects of vOTU diversity on enzyme activity and specificity, we assessed representative vOTUs spanning the Nairoviridae family towards Ub and ISG15 fluorogenic substrates. This revealed great variation in enzymatic activity and specific substrate preferences. A subset of the vOTUs were further assayed against eight biologically relevant di-Ub substrates, uncovering both common trends and distinct preferences of poly-Ub linkages by vOTUs. Four novel X-ray crystal structures were obtained that provide a biochemical rationale for vOTU substrate preferences and elucidate structural features that distinguish the vOTUs, including a motif in the Hughes orthonairovirus species that has not been previously observed in OTU domains. Additionally, structure-informed mutagenesis provided the first direct evidence of a second site involved in di-Ub binding for vOTUs. These results provide new insight into nairovirus evolution and pathogenesis, and further enhances the development of tools for therapeutic purposes. |
To address the unmet needs for human polyclonal antibodies both as therapeutics and diagnostic reagents, building upon our previously established transchromosomic (Tc) cattle platform, we report herein the development of a Tc goat system expressing human polyclonal antibodies in their sera. In the Tc goat system, a human artificial chromosome (HAC) comprising the entire human immunoglobulin (Ig) gene repertoire in the germline configuration was introduced into the genetic makeup of the domestic goat. We achieved this by transferring the HAC into goat fetal fibroblast cells followed by somatic cell nuclear transfer for Tc goat production. Gene and protein expression analyses in the peripheral blood mononuclear cells (PBMC) and the sera, respectively, of Tc caprine demonstrated the successful expression of human Ig genes and antibodies. Furthermore, immunization of Tc caprine with inactivated influenza A (H7N9) viruses followed by H7N9 Hemagglutinin 1 (HA1) boosting elicited human antibodies with high neutralizing activities against H7N9 viruses in vitro. As a small ungulate, Tc caprine offers the advantages of low cost and quick establishment of herds, therefore complementing the Tc cattle platform in responses to a range of medical needs and diagnostic applications where small volumes of human antibody products are needed. |
Sublingual immunization is emerging as an alternative to nasal immunization and induction of mucosal IgA responses. Using Bacillus anthracis edema toxin (EdTx) as an adjuvant, we previously showed that innate responses triggered after sublingual immunization could limit generation of IgA responses. We tested whether co-administration of a neutrophil elastase inhibitor (NEI) could rescue the ability of EdTx to induce broad antibody responses, including mucosal IgA. NEI supplementation of sublingual vaccines containing EdTx promoted antigen-specific serum IgA responses but also enhanced serum IgG1, and IgG2b responses. This enhancing effect of NEI did not extend to all antibody isotypes and IgG sublclasses, since NEI reduced serum IgE responses and did not affect IgG2a/c and IgG3 responses. NEI supplementation also promoted anti-Bacillus anthracis protective antigen (PA) neutralizing antibodies and enhanced high affinity IgG1 and IgA antibodies. In addition to serum IgA, NEI supplementation stimulated antigen-specific mucosal IgA responses in the GI tract, and enhanced antigen-specific IgG responses in vaginal washes. Analysis of CD4(+) T helper cell responses revealed that co-administration of NEI broadened the profile of cytokine responses, by stimulating Th1, Th2, Th17, and Tfh cytokines. We also noted that NEI had a higher stimulatory effect on IL-5, IL-10, IL-17 responses. |
BACKGROUND: China, which used to be an export country for migrants, has become a new destination for international migrants due to its rapid economic growth. However, little empirical data is available on the health status of and health service access barriers faced by these international migrants. METHODS: Foreigners who visited the Guangzhou Municipal Exit-Entry Administration Office to extend their visas were invited to participate in the study. Quantitative data were collected using electronic questionnaire in 13 languages. The participants were characterised by the income level of their country of origin (high-, middle- and low-income countries (HICs, MICs and LICs, respectively)), and the key factors associated with their health status, medical insurance coverage and perceptions of health services in China were examined. RESULTS: Overall, 1146 participants from 119 countries participated in the study, 57.1, 25.1 and 17.8% of whom were from MICs, HICs and LICs, respectively. Over one fifth of the participants experienced health problems while staying in China, and about half had no health insurance. Although the participants from HICs were more likely than those from MICs and LICs to have medical insurance, they were also more likely to have health problems. Furthermore, 43.0, 45.0 and 12.0% of the participants thought that the health services in China were good, fair and poor, respectively. Among the participants, those from HICs were less likely to have positive feedback. CONCLUSIONS: Our study is the first to report a quantitative survey of the health status, health insurance coverage, and health service perceptions of a diverse and surging population of international migrants in China. The findings call for more in-depth studies on the challenges presented by the increasing global migration to the health system. |
A 79-year-old gentleman presented with spontaneous pneumomediastinum and subcutaneous emphysema with pneumonia but no pre-existing lung disease. He presented with a 4-day history of increased shortness of breath, pleuritic chest pain, fevers, and non-productive cough. After 4 days of intravenous antibiotics, the patient developed considerable subcutaneous emphysema and pneumomediastinum. Pneumomediastinum presents most commonly with chest pain, shortness of breath, and subcutaneous emphysema. It has previously been associated with cases of pneumonia but often with rare strains such as P. jirovecii pneumonia in immunocompromised patients. This case highlights spontaneous pneumomediastinum as a rare complication of pneumonia. Treatment of pneumomediastinum is typically conservative, and although options may be limited, aggressive management of any causative factor may be essential in selected cases. LEARNING POINTS: Pneumomediastinum and subcutaneous emphysema are rare complications of pneumonia. Computerised tomography is a valuable diagnostic tool for identifying pneumomediastinum in patients with subcutaneous emphysema. While pneumomediastinum is typically a benign condition, aggressive management may occasionally be required. Evidence regarding use of non-invasive/invasive ventilation remains limited but it may theoretically aggravate any air leakage. |
East Africa is undergoing rapid expansion of pig rearing, driven by increasing pork consumption. Introduction and expansion of pig production systems in this biodiverse landscape may create new risks, including zoonotic pathogen transmission. Historically, biosecurity measures have primarily been focused at farm level, ignoring the important function pig traders fulfill between farmers and consumers. This study interviewed pig traders operating at Uganda’s only registered pork abattoir to describe their characteristics, business practices, biosecurity practices, and pig health management and reporting practices. All the traders were male, and nearly all (90.5%) relied on pig trading as their primary source of income. Most of the pigs brought for processing at the slaughterhouse were purchased from smallholder farms (87.3%). In addition, there was a significant difference in the high price paid per kilogram at farm gate by region (P = 0.005). High prices paid at farm gate were associated with holiday periods (P < 0.001), harvest season (P < 0.001), and drought (P < 0.001). Traders preferred buying live pigs from male farmers (88.9%) because they were considered the final decision makers and owned the pigs being sold. All pig traders were aware of clinical signs indicating a pig was sick. This study has provided baseline information on pig trader practices in Uganda. Improvements in local pork slaughterhouses and markets will benefit not only pig traders in accessing consistent customers but also individual pig farmers by increasing their market access. Finally, given their role as a link between farmers and consumers, traders would benefit from targeted inclusion in disease control and prevention strategies. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11250-018-1668-6) contains supplementary material, which is available to authorized users. |
BACKGROUND: The literature in statistics presents methods by which autocorrelation can identify the best period of measurement to improve the performance of a time-series prediction. The period of measurement plays an important role in improving the performance of disease-count predictions. However, from the operational perspective in public health surveillance, there is a limitation to the length of the measurement period that can offer meaningful and valuable predictions. OBJECTIVE: This study aimed to establish a method that identifies the shortest period of measurement without significantly decreasing the prediction performance for time-series analysis of disease counts. METHODS: The data used in this evaluation include disease counts from 2007 to 2017 in northern Nevada. The disease counts for chlamydia, salmonella, respiratory syncytial virus, gonorrhea, viral meningitis, and influenza A were predicted. RESULTS: Our results showed that autocorrelation could not guarantee the best performance for prediction of disease counts. However, the proposed method with the change-point analysis suggests a period of measurement that is operationally acceptable and performance that is not significantly different from the best prediction. CONCLUSIONS: The use of change-point analysis with autocorrelation provides the best and most practical period of measurement. |
Healthcare settings have played a major role in propagation of Ebola virus (EBOV) outbreaks. Healthcare workers (HCWs) have elevated risk of contact with EBOV-infected patients, particularly if safety precautions are not rigorously practiced. We conducted a serosurvey to determine seroprevalence against multiple EBOV antigens among HCWs of Boende Health Zone, Democratic Republic of the Congo, the site of a 2014 EBOV outbreak. Interviews and specimens were collected from 565 consenting HCWs. Overall, 234 (41.4%) of enrolled HCWs were reactive to at least 1 EBOV protein: 159 (28.1%) were seroreactive for anti-glycoprotein immunoglobulin G (IgG), 89 (15.8%) were seroreactive for anti-nucleoprotein IgG, and 54 (9.5%) were VP40 positive. Additionally, sera from 16 (2.8%) HCWs demonstrated neutralization capacity. These data demonstrate that a significant proportion of HCWs have the ability to neutralize virus, despite never having developed Ebola virus disease symptoms, highlighting an important and poorly documented aspect of EBOV infection and progression. |
In November 2018, yellow fever was diagnosed in a Dutch traveller returning from a bicycle tour in the Gambia-Senegal region. A complete genome sequence of yellow fever virus (YFV) from the case was generated and clustered phylogenetically with YFV from the Gambia and Senegal, ruling out importation into the Netherlands from recent outbreaks in Brazil or Angola. We emphasise the need for increased public awareness of YFV vaccination before travelling to endemic countries. |
INTRODUCTION: Robust metrics for national-level preparedness are critical for assessing global resilience to epidemic and pandemic outbreaks. However, existing preparedness assessments focus primarily on public health systems or specific legislative frameworks, and do not measure other essential capacities that enable and support public health preparedness and response. METHODS: We developed an Epidemic Preparedness Index (EPI) to assess national-level preparedness. The EPI is global, covering 188 countries. It consists of five subindices measuring each country’s economic resources, public health communications, infrastructure, public health systems and institutional capacity. To evaluate the construct validity of the EPI, we tested its correlation with proxy measures for preparedness and response capacity, including the timeliness of outbreak detection and reporting, as well as vaccination rates during the 2009 H1N1 influenza pandemic. RESULTS: The most prepared countries were concentrated in Europe and North America, while the least prepared countries clustered in Central and West Africa and Southeast Asia. Better prepared countries were found to report infectious disease outbreaks more quickly and to have vaccinated a larger proportion of their population during the 2009 pandemic. CONCLUSION: The EPI measures a country’s capacity to detect and respond to infectious disease events. Existing tools, such as the Joint External Evaluation (JEE), have been designed to measure preparedness within a country over time. The EPI complements the JEE by providing a holistic view of preparedness and is constructed to support comparative risk assessment between countries. The index can be updated rapidly to generate global estimates of pandemic preparedness that can inform strategy and resource allocation. |
Camels are livestock with unique adaptations to hot-arid regions. To effectively study camel traits, a biobank of camel DNA specimens with associated biological information is needed. We examined whole-blood, saliva (buccal swabs), and tail-hair follicle samples to determine which is the best source for establishing a DNA biobank. We inspected five amounts of each of whole-blood, buccal swabs, and tail-hair follicles in nine camels, both qualitatively via gel electrophoresis and quantitatively using a NanoDrop spectrophotometer. We also tested the effects of long term-storage on the quality and quantity of DNA, and measured the rate of degradation, by analyzing three buccal swab samples and 30 tail-hair follicles over a period of nine months. Good quality DNA, in the form of visible large size DNA bands, was extracted from all three sources, for all five amounts. The five volumes of whole-blood samples (20–100μl) provided ~0.4–3.6 μg, the five quantities of buccal swabs (1–5) produced ~0.1–12 μg, while the five amounts of tail-hair follicles (10–50) resulted in ~0.7–25 μg. No differences in the rate of degradation of buccal swab and tail-hair follicle DNA were detected, but there was clearly greater deterioration in the quality of DNA extracted from buccal swabs when compared to tail-hair follicles. We recommend using tail-hair samples for camel DNA biobanking, because it resulted in both an adequate quality and quantity of DNA, along with its ease of collection, transportation, and storage. Compared to its success in studies of other domesticated animals, we anticipate that using ~50 tail-hair follicles will provide sufficient DNA for sequencing or SNP genotyping. |
Zika virus (ZIKV) has been associated with serious health conditions, and an intense search to discover different ways to prevent and treat ZIKV infection is underway. Berberine and emodin possess several pharmacological properties and have been shown to be particularly effective against the entry and replication of several viruses. We show that emodin and berberine trigger a virucidal effect on ZIKV. When the virus was exposed to 160 µM of berberine, a reduction of 77.6% in the infectivity was observed; when emodin was used (40 µM), this reduction was approximately 83.3%. Dynamic light scattering data showed that both compounds significantly reduce the hydrodynamic radius of virus particle in solution. We report here that berberine and emodin, two natural compounds, have strong virucidal effect in Zika virus. |
The recombinant antibody fragments generated against the toxic components of scorpion venoms are considered a promising alternative for obtaining new antivenoms for therapy. Using directed evolution and site-directed mutagenesis, it was possible to generate a human single-chain antibody fragment with a broad cross-reactivity that retained recognition for its original antigen. This variant is the first antibody fragment that neutralizes the effect of an estimated 13 neurotoxins present in the venom of nine species of Mexican scorpions. This single antibody fragment showed the properties of a polyvalent antivenom. These results represent a significant advance in the development of new antivenoms against scorpion stings, since the number of components would be minimized due to their broad cross-neutralization capacity, while at the same time bypassing animal immunization. |
Many plant viruses express their proteins through a polyprotein strategy, requiring the acquisition of protease domains to regulate the release of functional mature proteins and/or intermediate polyproteins. Positive-strand RNA viruses constitute the vast majority of plant viruses and they are diverse in their genomic organization and protein expression strategies. Until recently, proteases encoded by positive-strand RNA viruses were described as belonging to two categories: (1) chymotrypsin-like cysteine and serine proteases and (2) papain-like cysteine protease. However, the functional characterization of plant virus cysteine and serine proteases has highlighted their diversity in terms of biological activities, cleavage site specificities, regulatory mechanisms, and three-dimensional structures. The recent discovery of a plant picorna-like virus glutamic protease with possible structural similarities with fungal and bacterial glutamic proteases also revealed new unexpected sources of protease domains. We discuss the variety of plant positive-strand RNA virus protease domains. We also highlight possible evolution scenarios of these viral proteases, including evidence for the exchange of protease domains amongst unrelated viruses. |
The rostral ventrolateral medulla (RVLM) is a key region in cardiovascular regulation. It has been demonstrated that cholinergic synaptic transmission in the RVLM is enhanced in hypertensive rats. Angiotensin-converting enzyme 2 (ACE2) in the brain plays beneficial roles in cardiovascular function in hypertension. The purpose of this study was to determine the effect of ACE2 overexpression in the RVLM on cholinergic synaptic transmission in spontaneously hypertensive rats (SHRs). Four weeks after injecting lentiviral particles containing enhanced green fluorescent protein and ACE2 bilaterally into the RVLM, the blood pressure and heart rate were notably decreased. ACE2 overexpression significantly reduced the concentration of acetylcholine in microdialysis fluid from the RVLM and blunted the decrease in blood pressure evoked by bilateral injection of atropine into the RVLM in SHRs. In conclusion, we suggest that ACE2 overexpression in the RVLM attenuates the enhanced cholinergic synaptic transmission in SHRs. |
Bronchial epithelial cells are the first target cell for rhinovirus infection. The course of viral infections in patients with acute bronchitis, asthma and COPD can be improved by oral application of Pelargonium sidoides radix extract; however, the mechanism is not well understood. This study investigated the in vitro effect of Pelargonium sidoides radix extract (EPs 7630) on the expression of virus binding cell membrane and host defence supporting proteins on primary human bronchial epithelial cells (hBEC). Cells were isolated from patients with severe asthma (n = 6), moderate COPD (n = 6) and non-diseased controls (n = 6). Protein expression was determined by Western-blot and immunofluorescence. Rhinovirus infection was determined by immunofluorescence as well as by polymerase chain reaction. Cell survival was determined by manual cell count after live/death immunofluorescence staining. All parameters were determined over a period of 3 days. The results show that EPs 7630 concentration-dependently and significantly increased hBEC survival after rhinovirus infection. This effect was paralleled by decreased expression of the inducible co-stimulator (ICOS), its ligand ICOSL and cell surface calreticulin (C1qR). In contrast, EPs 7630 up-regulated the expression of the host defence supporting proteins β-defensin-1 and SOCS-1, both in rhinovirus infected and un-infected hBEC. The expression of other virus interacting cell membrane proteins such as MyD88, TRL2/4 or ICAM-1 was not altered by EPs 7630. The results indicate that EPs 7630 may reduce rhinovirus infection of human primary BEC by down-regulating cell membrane docking proteins and up-regulating host defence proteins. |
Checkpoint protein inhibitor antibodies (CPI), including cytotoxic T-lymphocyte-associated antigen 4 inhibitors (ipilimumab, tremelimumab) and the programmed cell death protein 1 pathway/programmed cell death protein 1 ligand inhibitors (pembrolizumab, nivolumab, durvalumab, atezolizumab), have entered routine practice for the treatment of many cancers. They improve the outcome for many cancers, and more patients will be treated with CPI in the future. Although CPI can lead to adverse events (AE) less frequently than for chemotherapy, their use can require intensive care unit admission in case of severe immune-related adverse events (IrAE). Moreover, some of these events, particularly late events, are poorly documented, so a high level of suspicion should be maintained for patients receiving CPI. Intensivists should be aware in general of the known complications and appropriate management of these AE. Nevertheless, a multidisciplinary collaboration remains essential for their diagnosis and management. This review described the most severe complications related to CPI. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13613-019-0487-x) contains supplementary material, which is available to authorized users. |
BACKGROUND: Porcine circovirus type 2 (PCV2) is the causal agent of postweaning multisystemic wasting syndrome (PMWS), causing large economical losses of the global swine industry. Nitric oxide (NO), as an important signaling molecule, has antiviral activity on some viruses. To date, there is little information on the role of NO during PCV2 infection. RESULTS: We used indirect fluorescence assay (IFA), TCID(50), real-time RT-qPCR and western blot assay to reveal the role of NO in restricting PCV2 replication. PCV2 replication was inhibited by a form of NO, NO(•), whereas PCV2 was not susceptible to another form of NO, NO(+). CONCLUSION: Our findings indicate that the form of NO(•) has a potential role in the fight against PCV2 infection. |
BACKGROUND: To investigate the status of anti-tuberculosis treatment in critically ill patients, and to explore the value of APACHE-II score in guiding anti-tuberculosis treatment. METHODS: This analysis included critically ill patients with tuberculosis. The utility of APACHE-II score for predicting drug withdrawal was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: Among 320 patients enrolled (58 ± 22 years; 256 males), 147 (45.9%) had drugs withdrawn. The drug withdrawal group had higher APACHE-II score (median [interquartile range]: 21 [3–52] vs. 17 [4–42] points), higher CD4%, lower hemoglobin level, higher rates of chronic obstructive pulmonary disease (COPD) and chronic renal failure, and lower rate of extrapulmonary tuberculosis (P < 0.05). Logistic regression identified APACHE-II score > 18 (odds ratio [95% confidence interval]: 2.099 [1.321–3.334], P < 0.01), COPD (1.913 [1.028–3.561], P < 0.05) and hemoglobin level (0.987 [0.977–0.997], P < 0.05) as independent factors associated with drug withdrawal. At an optimal cutoff of 18.5, the sensitivity, specificity, positive predictive value and negative predictive value of APACHE-II score for predicting drug withdrawal was 59.2, 61.8, 56.9 and 64.1%, respectively. CONCLUSIONS: APACHE-II score > 18 points might predict patient tolerance of anti-tuberculosis treatment. |
Understanding the effect of media on disease spread can help improve epidemic forecasting and uncover preventive measures to slow the spread of disease. Most previously introduced models have approximated media effect through disease incidence, making media influence dependent on the size of epidemic. We propose an alternative approach, which relies on real data about disease coverage in the news, allowing us to model low incidence/high interest diseases, such as SARS, Ebola or H1N1. We introduce a network-based model, in which disease is transmitted through local interactions between individuals and the probability of transmission is affected by media coverage. We assume that media attention increases self-protection (e.g. hand washing and compliance with social distancing), which, in turn, decreases disease model. We apply the model to the case of H1N1 transmission in Mexico City in 2009 and show how media influence—measured by the time series of the weekly count of news articles published on the outbreak—helps to explain the observed transmission dynamics. We show that incorporating the media attention based on the observed media coverage of the outbreak better estimates the disease dynamics from what would be predicted by using media function that approximate the media impact using the number of cases and rate of spread. Finally, we apply the model to a typical influenza season in Washington, DC and estimate how the transmission pattern would have changed given different levels of media coverage. |
Macromolecular crowding decreases the diffusion rate, shifts the equilibrium of protein–protein and protein–substrate interactions, and changes protein conformational dynamics. Collectively, these effects contribute to enzyme catalysis. Here we describe how crowding may bias the conformational change and dynamics of enzyme populations and in this way affect catalysis. Crowding effects have been studied using artificial crowding agents and in vivo-like environments. These studies revealed a correlation between protein dynamics and function in the crowded environment. We suggest that crowded environments be classified into uniform crowding and structured crowding. Uniform crowding represents random crowding conditions created by synthetic particles with a narrow size distribution. Structured crowding refers to the highly coordinated cellular environment, where proteins and other macromolecules are clustered and organized. In structured crowded environments the perturbation of protein thermal stability may be lower; however, it may still be able to modulate functions effectively and dynamically. Dynamic, allosteric enzymes could be more sensitive to cellular perturbations if their free energy landscape is flatter around the native state; on the other hand, if their free energy landscape is rougher, with high kinetic barriers separating deep minima, they could be more robust. Above all, cells are structured; and this holds both for the cytosol and for the membrane environment. The crowded environment is organized, which limits the search, and the crowders are not necessarily inert. More likely, they too transmit allosteric effects, and as such play important functional roles. Overall, structured cellular crowding may lead to higher enzyme efficiency and specificity. |
Data on the genetic diversity of Pneumocystis jirovecii causing Pneumocystis pneumonia (PCP) among children are still limited, and there are no available data from the Indian subcontinent, particularly associations between genotypes and clinical characteristics. A total of 37 children (62 days-12 years [median 5.5 years]) were included in this study. Pneumocystis was diagnosed by microscopy using Grocott-Gomori methenamine silver stain in 12 cases and by nested PCR using mtLSUrRNA in 25 cases. Genotyping was performed using three different genes, mitochondrial large subunit ribosomal RNA (mtLSUrRNA), dihydropteroate synthase (DHPS) and dihydrofolate reductase (DHFR). mtLSUrRNA genotype 3 and novel mutations at the gene target DHFR (401 T > C) and DHPS 96/98 were frequently observed and clinically associated with severe PCP and treatment failure. Phylogenetic analyses revealed 13 unique sequence types (STs). Two STs (i) 3-DHFR 401 T > C-DHPS 96/98 – PJ1 and (ii) 3-DHFR 401 T > C-DHPS 96- PJ3 were significantly associated with treatment failure and high mortality among PCP-positive patients. In conclusion, the present study strongly suggests the emergence of virulent P. jirovecii strains or genetic polymorphisms, leading to treatment failure and high mortality. Our study is the first of its kind from the Indian subcontinent and has highlighted the genetic diversity of Pneumocystis jirovecii among children and their clinical outcomes. These findings emphasize the need to focus more on genotypes to better understand the epidemiology of Pneumocystis pneumonia. |
BACKGROUND: Diabetes mellitus is a chronic disease with a steadfast increase in prevalence. Due to the chronic course of the disease combining with devastating complications, this disorder could easily carry a financial burden. The early diagnosis of diabetes remains as one of the major challenges medical providers are facing, and the satisfactory screening tools or methods are still required, especially a population- or community-based tool. METHODS: This is a retrospective cross-sectional study involving 15,323 subjects who underwent the annual check-up in the Department of Family Medicine of Shengjing Hospital of China Medical University from January 2017 to June 2017. With a strict data filtration, 10,436 records from the eligible participants were utilized to develop a prediction model using the J48 decision tree algorithm. Nine variables, including age, gender, body mass index (BMI), hypertension, history of cardiovascular disease or stroke, family history of diabetes, physical activity, work-related stress, and salty food preference, were considered. RESULTS: The accuracy, precision, recall, and area under the receiver operating characteristic curve (AUC) value for identifying potential diabetes were 94.2%, 94.0%, 94.2%, and 94.8%, respectively. The structure of the decision tree shows that age is the most significant feature. The decision tree demonstrated that among those participants with age ≤ 49, 5497 participants (97%) of the individuals were identified as nondiabetic, while age > 49, 771 participants (50%) of the individuals were identified as nondiabetic. In the subgroup where people were 34 < age ≤ 49 and BMI ≥ 25, when with positive family history of diabetes, 89 (92%) out of 97 individuals were identified as diabetic and, when without family history of diabetes, 576 (58%) of the individuals were identified as nondiabetic. Work-related stress was identified as being associated with diabetes. In individuals with 34 < age ≤ 49 and BMI ≥ 25 and without family history of diabetes, 22 (51%) of the individuals with high work-related stress were identified as nondiabetic while 349 (88%) of the individuals with low or moderate work-related stress were identified as not having diabetes. CONCLUSIONS: We proposed a classifier based on a decision tree which used nine features of patients which are easily obtained and noninvasive as predictor variables to identify potential incidents of diabetes. The classifier indicates that a decision tree analysis can be successfully applied to screen diabetes, which will support clinical practitioners for rapid diabetes identification. The model provides a means to target the prevention of diabetes which could reduce the burden on the health system through effective case management. |
Cellular membranes are continuously remodeled. The crescent-shaped bin-amphiphysin-rvs (BAR) domains remodel membranes in multiple cellular pathways. Based on studies of isolated BAR domains in vitro, the current paradigm is that BAR domain–containing proteins polymerize into cylindrical scaffolds that stabilize lipid tubules. But in nature, proteins that contain BAR domains often also contain large intrinsically disordered regions. Using in vitro and live cell assays, here we show that full-length BAR domain–containing proteins, rather than stabilizing membrane tubules, are instead surprisingly potent drivers of membrane fission. Specifically, when BAR scaffolds assemble at membrane surfaces, their bulky disordered domains become crowded, generating steric pressure that destabilizes lipid tubules. More broadly, we observe this behavior with BAR domains that have a range of curvatures. These data suggest that the ability to concentrate disordered domains is a key driver of membrane remodeling and fission by BAR domain–containing proteins. |
BACKGROUND: In the spring of 1918, the “War to End All Wars”, which would ultimately claim more than 37 million lives, had entered into its final year and would change the global political and economic landscape forever. At the same time, a new global threat was emerging and would become one of the most devastating global health crises in recorded history. MAIN TEXT: The 1918 H1N1 pandemic virus spread across Europe, North America, and Asia over a 12-month period resulting in an estimated 500 million infections and 50–100 million deaths worldwide, of which ~ 50% of these occurred within the fall of 1918 (Emerg Infect Dis 12:15-22, 2006, Bull Hist Med 76:105-115, 2002). However, the molecular factors that contributed to the emergence of, and subsequent public health catastrophe associated with, the 1918 pandemic virus remained largely unknown until 2005, when the characterization of the reconstructed pandemic virus was announced heralding a new era of advanced molecular investigations (Science 310:77-80, 2005). In the century following the emergence of the 1918 pandemic virus we have landed on the Moon, developed the electronic computer (and a global internet), and have eradicated smallpox. In contrast, we have a largely remedial knowledge and understanding of one of the greatest scourges in recorded history. CONCLUSION: Here, we reflect on the 1918 influenza pandemic, including its emergence and subsequent rapid global spread. In addition, we discuss the pathophysiology associated with the 1918 virus and its predilection for the young and healthy, the rise of influenza therapeutic research following the pandemic, and, finally, our level of preparedness for future pandemics. |
When analysing new emerging infectious disease outbreaks, one typically has observational data over a limited period of time and several parameters to estimate, such as growth rate, the basic reproduction number R(0), the case fatality rate and distributions of serial intervals, generation times, latency and incubation times and times between onset of symptoms, notification, death and recovery/discharge. These parameters form the basis for predicting a future outbreak, planning preventive measures and monitoring the progress of the disease outbreak. We study inference problems during the emerging phase of an outbreak, and point out potential sources of bias, with emphasis on: contact tracing backwards in time, replacing generation times by serial intervals, multiple potential infectors and censoring effects amplified by exponential growth. These biases directly affect the estimation of, for example, the generation time distribution and the case fatality rate, but can then propagate to other estimates such as R(0) and growth rate. We propose methods to remove or at least reduce bias using statistical modelling. We illustrate the theory by numerical examples and simulations. |
[Image: see text] APOBEC3 enzymes form part of the innate immune system by deaminating cytosine to uracil in single-stranded DNA (ssDNA) and thereby preventing the spread of pathogenic genetic information. However, APOBEC mutagenesis is also exploited by viruses and cancer cells to increase rates of evolution, escape adaptive immune responses, and resist drugs. This raises the possibility of APOBEC3 inhibition as a strategy for augmenting existing antiviral and anticancer therapies. Here we show that, upon incorporation into short ssDNAs, the cytidine nucleoside analogue 2′-deoxyzebularine (dZ) becomes capable of inhibiting the catalytic activity of selected APOBEC variants derived from APOBEC3A, APOBEC3B, and APOBEC3G, supporting a mechanism in which ssDNA delivers dZ to the active site. Multiple experimental approaches, including isothermal titration calorimetry, fluorescence polarization, protein thermal shift, and nuclear magnetic resonance spectroscopy assays, demonstrate nanomolar dissociation constants and low micromolar inhibition constants. These dZ-containing ssDNAs constitute the first substrate-like APOBEC3 inhibitors and, together, comprise a platform for developing nucleic acid-based inhibitors with cellular activity. |
Membrane proteins (such as ion channels, transporters, and receptors) and secreted proteins are essential for cellular activities. N-linked glycosylation is involved in stability and function of these proteins and occurs at Asn residues. In several organs, profiles of N-glycans have been determined by comprehensive analyses. Nevertheless, the cochlea of the mammalian inner ear, a tiny organ mediating hearing, has yet to be examined. Here, we focused on the stria vascularis, an epithelial-like tissue in the cochlea, and characterised N-glycans by liquid chromatography with mass spectrometry. This hypervascular tissue not only expresses several ion transporters and channels to control the electrochemical balance in the cochlea but also harbours different transporters and receptors that maintain structure and activity of the organ. Seventy-nine N-linked glycans were identified in the rat stria vascularis. Among these, in 55 glycans, the complete structures were determined; in the other 24 species, partial glycosidic linkage patterns and full profiles of the monosaccharide composition were identified. In the process of characterisation, several sialylated glycans were subjected sequentially to two different alkylamidation reactions; this derivatisation helped to distinguish α2,3-linkage and α2,6-linkage sialyl isomers with mass spectrometry. These data should accelerate elucidation of the molecular architecture of the cochlea. |
The amyloid precursor protein plus presenilin-1 (APP/PS1) mice are a frequently-used model for Alzheimer's disease studies (AD). However, the data relevant to which proteins are involved in inflammatory mechanism are not sufficiently well-studied using the AD mouse model. Using behavioral studies, quantitative RT-PCR and Western-blot techniques, significant findings were determined by the expression of proteins involved in inflammation comparing APP/PS1 and Wild type mice. Increased GFAP expression could be associated with the elevation in number of reactive astrocytes. IL-3 is involved in inflammation and ABDF1 intervenes normally in the transport across cell membranes and both were found up-regulated in APP/PS1 mice compared to Wild type mice. Furthermore, CCR5 expression was decreased and both CCL3 and CCL4 chemokines were highly expressed indicating a possible gliosis and probably an increase in chemotaxis from lymphocytes and T cell generation. We also noted for the first time, a CCR8 increase expression with diminution of its CCL1 chemokine, both normally involved in protection from bacterial infection and demyelination. Control of inflammatory proteins will be the next step in understanding the progression of AD and also in determining the mechanisms that can develop in this disease. |
PURPOSE: The aim of the present study was to develop a serodiagnostic test for differentiation infected from vaccinated animal (DIVA) strategy accompanying the marker vaccine lacking an immunodominant epitope (IDE) of nucleoprotein of Newcastle disease virus (NDV). MATERIALS AND METHODS: Recombinant epitope-repeat protein (rERP) gene encoding eight repeats of the IDE sequence (ETQFLDLMRAVANSMR) by tetra-glycine linker was synthesized. Recombinant baculovirus carrying the rERP gene was generated to express the rERP in insect cells. Specificity and sensitivity of an indirect enzyme-linked immunosorbent assay (ELISA) employing the rERP was evaluated. RESULTS: The rERP with molecular weight of 20 kDa was successfully expressed by the recombinant baculovirus in an insect-baculovirus system. The rERP was antigenically functional as demonstrated by Western blotting. An indirect ELISA employing the rERP was developed and its specificity and sensitivity was determined. The ELISA test allowed discrimination of NDV infected sera from epitope deletion virus vaccinated sera. CONCLUSION: The preliminary results represent rERP ELISA as a promising DIVA diagnostic tool. |
Central players of the adaptive immune system are the groups of proteins encoded in the major histocompatibility complex (MHC), which shape the immune response against pathogens and tolerance to self-peptides. The corresponding genomic region is of particular interest, as it harbors more disease associations than any other region in the human genome, including associations with infectious diseases, autoimmune disorders, cancers, and neuropsychiatric diseases. Certain MHC molecules can bind to a much wider range of epitopes than others, but the functional implication of such an elevated epitope-binding repertoire has remained largely unclear. It has been suggested that by recognizing more peptide segments, such promiscuous MHC molecules promote immune response against a broader range of pathogens. If so, the geographical distribution of MHC promiscuity level should be shaped by pathogen diversity. Three lines of evidence support the hypothesis. First, we found that in pathogen-rich geographical regions, humans are more likely to carry highly promiscuous MHC class II DRB1 alleles. Second, the switch between specialist and generalist antigen presentation has occurred repeatedly and in a rapid manner during human evolution. Third, molecular positions that define promiscuity level of MHC class II molecules are especially diverse and are under positive selection in human populations. Taken together, our work indicates that pathogen load maintains generalist adaptive immune recognition, with implications for medical genetics and epidemiology. |
The enterovirus genus of the picornavirus family includes a large number of important human pathogens such as poliovirus, coxsackievirus, enterovirus A71, and rhinoviruses. Like all other positive-strand RNA viruses, genome replication of enteroviruses occurs on rearranged membranous structures called replication organelles (ROs). Phosphatidylinositol 4-kinase IIIβ (PI4KB) is required by all enteroviruses for RO formation. The enteroviral 3A protein recruits PI4KB to ROs, but the exact mechanism remains elusive. Here, we investigated the role of acyl-coenzyme A binding domain containing 3 (ACBD3) in PI4KB recruitment upon enterovirus replication using ACBD3 knockout (ACBD3(KO)) cells. ACBD3 knockout impaired replication of representative viruses from four enterovirus species and two rhinovirus species. PI4KB recruitment was not observed in the absence of ACBD3. The lack of ACBD3 also affected the localization of individually expressed 3A, causing 3A to localize to the endoplasmic reticulum instead of the Golgi. Reconstitution of wild-type (wt) ACBD3 restored PI4KB recruitment and 3A localization, while an ACBD3 mutant that cannot bind to PI4KB restored 3A localization, but not virus replication. Consistently, reconstitution of a PI4KB mutant that cannot bind ACBD3 failed to restore virus replication in PI4KB(KO) cells. Finally, by reconstituting ACBD3 mutants lacking specific domains in ACBD3(KO) cells, we show that acyl-coenzyme A binding (ACB) and charged-amino-acid region (CAR) domains are dispensable for 3A-mediated PI4KB recruitment and efficient enterovirus replication. Altogether, our data provide new insight into the central role of ACBD3 in recruiting PI4KB by enterovirus 3A and reveal the minimal domains of ACBD3 involved in recruiting PI4KB and supporting enterovirus replication. |
Degenerative retinal disease leads to significant visual morbidity worldwide. Diabetic retinopathy and macular degeneration are leading causes of blindness in the developed world. While current therapies for these diseases slow disease progression, stem cell and gene therapy may also reverse the effects of these, and other, degenerative retinal conditions. Novel therapies being investigated include the use of various types of stem cells in the regeneration of atrophic or damaged retinal tissue, the prolonged administration of neurotrophic factors and/or drug delivery, immunomodulation, as well as the replacement of mutant genes, and immunomodulation through viral vector delivery. This review will update the reader on aspects of stem cell and gene therapy in diabetic retinopathy, age-related macular degeneration, retinitis pigmentosa and other less common inherited retinal dystrophies. These therapies include the use of adeno-associated viral vector-based therapies for treatment of various types of retinitis pigmentosa and dry age-related macular degeneration. Other potential therapies reviewed include the use of mesenchymal stem cells in local immunomodulation, and the use of stem cells in generating structures like three-dimensional retinal sheets for transplantation into degenerative retinas. Finally, aspects of stem cell and gene therapy in diabetic retinopathy, age-related macular degeneration, retinitis pigmentosa, and other less common inherited retinal dystrophies will be reviewed. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
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. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.