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1,600 | Pathophysiology and biomarkers of acute respiratory distress syndrome | Acute respiratory distress syndrome (ARDS) is defined as an acute-onset, progressive, hypoxic condition with radiographic bilateral lung infiltration, which develops after several diseases or injuries, and is not derived from hydrostatic pulmonary edema. One specific pathological finding of ARDS is diffuse alveolar damage. In 2012, in an effort to increase diagnostic specificity, a revised definition of ARDS was published in JAMA. However, no new parameters or biomarkers were adopted by the revised definition. Discriminating between ARDS and other similar diseases is critically important; however, only a few biomarkers are currently available for diagnostic purposes. Furthermore, predicting the severity, response to therapy, or outcome of the illness is also important for developing treatment strategies for each patient. However, the PaO(2)/FIO(2) ratio is currently the sole clinical parameter used for this purpose. In parallel with progress in understanding the pathophysiology of ARDS, various humoral factors induced by inflammation and molecules derived from activated cells or injured tissues have been shown as potential biomarkers that may be applied in clinical practice. In this review, the current understanding of the basic pathophysiology of ARDS and associated candidate biomarkers will be discussed. |
1,601 | Genome Sequence of Torovirus Identified from a Pig with Porcine Epidemic Diarrhea Virus from the United States | Porcine torovirus (PToV) strain PToV-NPL/2013 was identified from a pig that tested positive for porcine epidemic diarrhea virus (PEDV). The spike protein-encoding gene from PToV-NPL/2013 had 92% identity with PToV-SH1, suggesting that PToV circulating in the United States is slightly different from the isolates circulating in China. To our knowledge, this is the first report of PToV in the United States. |
1,602 | Xyloketal B, a marine compound, acts on a network of molecular proteins and regulates the activity and expression of rat cytochrome P450 3a: a bioinformatic and animal study | Natural compounds are becoming popular for the treatment of illnesses and health promotion, but the mechanisms of action and safety profiles are often unknown. Xyloketal B (XKB) is a novel marine compound isolated from the mangrove fungus Xylaria sp., with potent antioxidative, neuroprotective, and cardioprotective effects. However, its molecular targets and effects on drug-metabolizing enzymes are unknown. This study aimed to investigate the potential molecular targets of XKB using bioinformatic approaches and to examine the effect of XKB on the expression and activity of rat cytochrome P450 3a (Cyp3a) subfamily members using midazolam as a model probe. DDI-CPI, a server that can predict drug–drug interactions via the chemical–protein interactome, was employed to predict the targets of XKB, and the Database for Annotation, Visualization and Integrated Discovery (DAVID) was used to analyze the pathways of the predicted targets of XKB. Homology modeling was performed using the Discovery Studio program 3.1. The activity and expression of rat hepatic Cyp3a were examined after the rats were treated with XKB at 7 and 14 mg/kg for 8 consecutive days. Rat plasma concentrations of midazolam and its metabolite 1′-OH-midazolam were determined using a validated high-performance liquid chromatographic method. Bioinformatic analysis showed that there were over 324 functional proteins and 61 related signaling pathways that were potentially regulated by XKB. A molecular docking study showed that XKB bound to the active site of human cytochrome P450 3A4 and rat Cyp3a2 homology model via the formation of hydrogen bonds. The in vivo study showed that oral administration of XKB at 14 mg/kg to rats for 8 days significantly increased the area under the plasma concentration-time curve (AUC) of midazolam, with a concomitant decrease in the plasma clearance and AUC ratio of 1′-OH-midazolam over midazolam. Further, oral administration of 14 mg/kg XKB for 8 days markedly reduced the activity and expression of hepatic Cyp3a in rats. Taken together, the results show that XKB could regulate networks of molecular proteins and related signaling pathways and that XKB downregulated hepatic Cyp3a in rats. XKB might cause drug interactions through modulation of the activity and expression of Cyp3a members. More studies are warranted to confirm the mechanisms of action of XKB and to investigate the underlying mechanism for the regulating effect of XKB on Cyp3a subfamily members. |
1,603 | Attenuating effect of Ginsenoside Rb1 on LPS-induced lung injury in rats | BACKGROUND: Sepsis causes neutrophil sequestration in the lung which leads to acute lung injury (ALI). Radix Ginseng (RG), a traditional herb used as herbal remedy in eastern Asia for thousands of years, which has been traditionally used in China to improve blood circulation and ameliorate pathological hemostasis. This study investigated whether Ginsenoside Rb1, the main components of RG, can attenuate ALI induced by LPS. METHODS: In vivo, 30 male Wistar rats were divided into three groups (n = 10 each groups) on the basis of the reagent used, which were subjected to LPS injection with or without Ginsenoside Rb1 (5 mg/kg) treatments to induce ALI model. Lung injury was assessed by pulmonary histology, lung wet-weight to dry-weight (W/D) ratio, the number of myeloperoxidase (MPO) positive cells, immunohistochemical analysis of intercellular adhesion molecule-1 (ICAM-1), gene expression of ICAM-1, ultrastructure changes of pulmonary microvasculature, concentration of inflammatory markers and in plasma. In vitro, pulmonary microvascular endothelial cells (PMVECs) were stimulated with LPS in the presence and absence of Ginsenoside Rb1 (50 mM), nuclear factor-κB (NF-κB) p65 was measured by immunocytochemistry staining and western blotting. RESULTS: Infusion of LPS induced lung injury, in vivo, as demonstrated by pulmonary edema with infiltration of neutrophils and hemorrhage, the increase in lung W/D ratio, the number of MPO positive cells, the level of inflammatory markers such as TNF-α, MCP-1 and IL-8, enhanced expression of ICAM-1 and ICAM-1 gene. Moreover, resulted in the changes of intercellular junctions in the endothelial cells of pulmonary microvasculature. In vitro, the significant increased release of NF-κB p65 and its subsequent translocation into the nucleus in PMVECs were observed. In contrast, Ginsenoside Rb1 treatment significantly ameliorated the LPS-induced lung injury, as judged by the marked improvement in all these indices. CONCLUSIONS: These results indicate that Ginsenoside Rb1 attenuated LPS-induced lung injury through an inhibition of the inflammatory signaling pathway, besides the direct inhibitory effect on proinflammatory molecules. |
1,604 | Chemical and Biological Mechanisms of Pathogen Reduction Technologies | Within the last decade new technologies have been developed and implemented which employ light, often in the presence of a photosensitizer, to inactivate pathogens that reside in human blood products for the purpose of transfusion. These pathogen reduction technologies attempt to find the proper balance between pathogen kill and cell quality. Each system utilizes various chemistries that not only impact which pathogens they can inactivate and how, but also how the treatments affect the plasma and cellular proteins and to what degree. This paper aims to present the various chemical mechanisms for pathogen reduction in transfusion medicine that are currently practiced or in development. |
1,605 | Pathway and Network Approaches for Identification of Cancer Signature Markers from Omics Data | The advancement of high throughput omic technologies during the past few years has made it possible to perform many complex assays in a much shorter time than the traditional approaches. The rapid accumulation and wide availability of omic data generated by these technologies offer great opportunities to unravel disease mechanisms, but also presents significant challenges to extract knowledge from such massive data and to evaluate the findings. To address these challenges, a number of pathway and network based approaches have been introduced. This review article evaluates these methods and discusses their application in cancer biomarker discovery using hepatocellular carcinoma (HCC) as an example. |
1,606 | Novel PDE4 Inhibitors Derived from Chinese Medicine Forsythia | Cyclic adenosine monophosphate (cAMP) is a crucial intracellular second messenger molecule that converts extracellular molecules to intracellular signal transduction pathways generating cell- and stimulus-specific effects. Importantly, specific phosphodiesterase (PDE) subtypes control the amplitude and duration of cAMP-induced physiological processes and are therefore a prominent pharmacological target currently used in a variety of fields. Here we tested the extracts from traditional Chinese medicine, Forsythia suspense seeds, which have been used for more than 2000 years to relieve respiratory symptoms. Using structural-functional analysis we found its major lignin, Forsynthin, acted as an immunosuppressant by inhibiting PDE4 in inflammatory and immune cell. Moreover, several novel, selective small molecule derivatives of Forsythin were tested in vitro and in murine models of viral and bacterial pneumonia, sepsis and cytokine-driven systemic inflammation. Thus, pharmacological targeting of PDE4 may be a promising strategy for immune-related disorders characterized by amplified host inflammatory response. |
1,607 | Finding and identifying the viral needle in the metagenomic haystack: trends and challenges | Collectively, viruses have the greatest genetic diversity on Earth, occupy extremely varied niches and are likely able to infect all living organisms. Viral infections are an important issue for human health and cause considerable economic losses when agriculturally important crops or husbandry animals are infected. The advent of metagenomics has provided a precious tool to study viruses by sampling them in natural environments and identifying the genomic composition of a sample. However, reaching a clear recognition and taxonomic assignment of the identified viruses has been hampered by the computational difficulty of these problems. In this perspective paper we examine the trends in current research for the identification of viral sequences in a metagenomic sample, pinpoint the intrinsic computational difficulties for the identification of novel viral sequences within metagenomic samples, and suggest possible avenues to overcome them. |
1,608 | ACE2: Angiotensin II/Angiotensin-(1-7) balance in cardiorenal injury | Our current recognition of the renin-angiotensin system is more convoluted than originally thought due to the discovery of multiple novel enzymes, peptides, and receptors inherent to this interactive biochemical cascade. Over the last decade angiotensin converting enzyme 2 (ACE2) has emerged as a key player in the pathophysiology of hypertension and cardiovascular and renal disease due to its pivotal role in metabolizing vasoconstrictive/hypertrophic/proliferative angiotensin II into favorable angiotensin-(1-7). This review addresses a considerable advancement in research on the role of tissue ACE2 in development and progression of hypertension and cardiorenal injury. We also summarize the results from recent clinical and experimental studies suggesting that serum or urine soluble ACE2 may serve as a novel biomarker or independent risk factor relevant for diagnosis and prognosis of cardiorenal disease. Recent proceedings on novel therapeutic approaches to enhance ACE2/angiotensin-(1-7) axis are also reviewed. |
1,609 | Bi-specific splice-switching PMO oligonucleotides conjugated via a single peptide active in a mouse model of Duchenne muscular dystrophy | The potential for therapeutic application of splice-switching oligonucleotides (SSOs) to modulate pre-mRNA splicing is increasingly evident in a number of diseases. However, the primary drawback of this approach is poor cell and in vivo oligonucleotide uptake efficacy. Biological activities can be significantly enhanced through the use of synthetically conjugated cationic cell penetrating peptides (CPPs). Studies to date have focused on the delivery of a single SSO conjugated to a CPP, but here we describe the conjugation of two phosphorodiamidate morpholino oligonucleotide (PMO) SSOs to a single CPP for simultaneous delivery and pre-mRNA targeting of two separate genes, exon 23 of the Dmd gene and exon 5 of the Acvr2b gene, in a mouse model of Duchenne muscular dystrophy. Conjugations of PMOs to a single CPP were carried out through an amide bond in one case and through a triazole linkage (‘click chemistry’) in the other. The most active bi-specific CPP–PMOs demonstrated comparable exon skipping levels for both pre-mRNA targets when compared to individual CPP–PMO conjugates both in cell culture and in vivo in the mdx mouse model. Thus, two SSOs with different target sequences conjugated to a single CPP are biologically effective and potentially suitable for future therapeutic exploitation. |
1,610 | Subgenomic promoter recognition by the norovirus RNA-dependent RNA polymerases | The replication enzyme of RNA viruses must preferentially recognize their RNAs in an environment that contains an abundance of cellular RNAs. The factors responsible for specific RNA recognition are not well understood, in part because viral RNA synthesis takes place within enzyme complexes associated with modified cellular membrane compartments. Recombinant RNA-dependent RNA polymerases (RdRps) from the human norovirus and the murine norovirus (MNV) were found to preferentially recognize RNA segments that contain the promoter and a short template sequence for subgenomic RNA synthesis. Both the promoter and template sequence contribute to stable RdRp binding, accurate initiation of the subgenomic RNAs and efficient RNA synthesis. Using a method that combines RNA crosslinking and mass spectrometry, residues near the template channel of the MNV RdRp were found to contact the hairpin RNA motif. Mutations in the hairpin contact site in the MNV RdRp reduced MNV replication and virus production in cells. This work demonstrates that the specific recognition of the norovirus subgenomic promoter is through binding by the viral RdRp. |
1,611 | Using Modelling to Disentangle the Relative Contributions of Zoonotic and Anthroponotic Transmission: The Case of Lassa Fever | BACKGROUND: Zoonotic infections, which transmit from animals to humans, form the majority of new human pathogens. Following zoonotic transmission, the pathogen may already have, or may acquire, the ability to transmit from human to human. With infections such as Lassa fever (LF), an often fatal, rodent-borne, hemorrhagic fever common in areas of West Africa, rodent-to-rodent, rodent-to-human, human-to-human and even human-to-rodent transmission patterns are possible. Indeed, large hospital-related outbreaks have been reported. Estimating the proportion of transmission due to human-to-human routes and related patterns (e.g. existence of super-spreaders), in these scenarios is challenging, but essential for planned interventions. METHODOLOGY/PRINCIPAL FINDINGS: Here, we make use of an innovative modeling approach to analyze data from published outbreaks and the number of LF hospitalized patients to Kenema Government Hospital in Sierra Leone to estimate the likely contribution of human-to-human transmission. The analyses show that almost [Image: see text] of the cases at KGH are secondary cases arising from human-to-human transmission. However, we found much of this transmission is associated with a disproportionally large impact of a few individuals (‘super-spreaders’), as we found only [Image: see text] of human cases result in an effective reproduction number (i.e. the average number of secondary cases per infectious case) [Image: see text], with a maximum value up to [Image: see text]. CONCLUSIONS/SIGNIFICANCE: This work explains the discrepancy between the sizes of reported LF outbreaks and a clinical perception that human-to-human transmission is low. Future assessment of risks of LF and infection control guidelines should take into account the potentially large impact of super-spreaders in human-to-human transmission. Our work highlights several neglected topics in LF research, the occurrence and nature of super-spreading events and aspects of social behavior in transmission and detection. |
1,612 | CryptoDex: A randomised, double-blind, placebo-controlled phase III trial of adjunctive dexamethasone in HIV-infected adults with cryptococcal meningitis: study protocol for a randomised control trial | BACKGROUND: Cryptococcal meningitis (CM) is a severe AIDS-defining illness with 90-day case mortality as high as 70% in sub-Saharan Africa, despite treatment. It is the leading cause of death in HIV patients in Asia and Africa. No major advance has been made in the treatment of CM since the 1970s. The mainstays of induction therapy are amphotericin B and flucytosine, but these are often poorly available where the disease burden is highest. Adjunctive treatments, such as dexamethasone, have had dramatic effects on mortality in other neurologic infections, but are untested in CM. Given the high death rates in patients receiving current optimal treatment, and the lack of new agents on the horizon, adjuvant treatments, which offer the potential to reduce mortality in CM, should be tested. The principal research question posed by this study is as follows: does adding dexamethasone to standard antifungal therapy for CM reduce mortality? Dexamethasone is a cheap, readily available, and practicable intervention. METHOD: A double-blind placebo-controlled trial with parallel arms in which patients are randomised to receive either dexamethasone or placebo, in addition to local standard of care. The study recruits patients in both Asia and Africa to ensure the relevance of its results to the populations in which the disease burden is highest. The 10-week mortality risk in the control group is expected to be between 30% and 50%, depending on location, and the target hazard ratio of 0.7 corresponds to absolute risk reductions in mortality from 30% to 22%, or from 50% to 38%. Assuming an overall 10-week mortality of at least 30% in our study population, recruitment of 824 patients will be sufficient to observe the expected number of deaths. Allowing for some loss to follow-up, the total sample size for this study is 880 patients. To generate robust evidence across both continents, we aim to recruit roughly similar numbers of patients from each continent. The primary end point is 10-week mortality. Ethical approval has been obtained from Oxford University’s Tropical Research Ethics Committee (OxTREC), and as locally mandated at each site. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number: ISRCTN59144167 26-July-2012 |
1,613 | “Only your blood can tell the story” – a qualitative research study using semi- structured interviews to explore the hepatitis B related knowledge, perceptions and experiences of remote dwelling Indigenous Australians and their health care providers in northern Australia | BACKGROUND: Hepatitis B is endemic in the Indigenous communities of the Northern Territory of Australia and significantly contributes to liver-related morbidity and mortality. It is recognised that low health literacy levels, different worldviews and English as a second language all contribute to the difficulties health workers often have in explaining biomedical health concepts, relevant to hepatitis B infection, to patients. The aim of this research project was to explore the knowledge, perceptions and experiences of remote dwelling Indigenous adults and their health care providers relating to hepatitis B infection with a view to using this as the evidence base to develop a culturally appropriate educational tool. METHODS: The impetus for this project came from health clinic staff at a remote community in Arnhem Land in the Northern Territory, in partnership with a visiting specialist liver clinic from the Royal Darwin Hospital. Participants were clinic patients with hepatitis B (n = 12), community members (n = 9) and key informants (n = 13); 25 were Indigenous individuals. A participatory action research project design was used with purposive sampling to identify participants. Semi-structured interviews were undertaken to explore: current understanding of hepatitis B, desire for knowledge, and perspectives on how people could acquire the information needed. All individuals were offered the use of an interpreter. The data were examined using deductive and inductive thematic analysis. RESULTS: Low levels of biomedical knowledge about Hepatitis B, negative perceptions of Hepatitis B, communication (particularly language) and culture were the major themes that emerged from the data. Accurate concepts grounded in Indigenous culture such as “only your blood can tell the story” were present but accompanied by a feeling of disempowerment due to perceived lack of “medical” understanding, and informed partnerships between caregiver and patient. Culturally appropriate discussions in a patient’s first language using visual aids were identified as vital to improving communication. CONCLUSIONS: Having an educational tool in Indigenous patient’s first language is crucial in developing treatment partnerships for Indigenous patients with hepatitis B. Using a culturally appropriate worldview as the foundation for development should help to reduce disempowerment and improve health literacy. |
1,614 | Unequivocal glycyrrhizin isomer determination and comparative in vitro bioactivities of root extracts in four Glycyrrhiza species | Glycyrrhiza glabra, commonly known as licorice, is a popular herbal supplement used for the treatment of chronic inflammatory conditions and as sweetener in the food industry. This species contains a myriad of phytochemicals including the major saponin glycoside glycyrrhizin (G) of Glycyrrhetinic acid (GA) aglycone. In this study, 2D-ROESY NMR technique was successfully applied for distinguishing 18α and 18β glycyrrhetinic acid (GA). ROESY spectra acquired from G. glabra, Glycyrrhiza uralensis and Glycyrrhiza inflata crude extracts revealed the presence of G in its β-form. Anti-inflammatory activity of four Glycyrrhiza species, G, glabra, G. uralensis, G. inflata, and G. echinata roots was assessed against COX-1 inhibition revealing that phenolics rather than glycyrrhizin are biologically active in this assay. G. inflata exhibits a strong cytotoxic effect against PC3 and HT29 cells lines, whereas other species are inactive. This study presents an effective NMR method for G isomer assignment in licorice extracts that does not require any preliminary chromatography or any other purification step. |
1,615 | Poultry farms as a source of avian influenza A (H7N9) virus reassortment and human infection | Live poultry markets are a source of human infection with avian influenza A (H7N9) virus. On February 21, 2014, a poultry farmer infected with H7N9 virus was identified in Jilin, China, and H7N9 and H9N2 viruses were isolated from the patient's farm. Reassortment between these subtype viruses generated five genotypes, one of which caused the human infection. The date of H7N9 virus introduction to the farm is estimated to be between August 21, 2013 (95% confidence interval [CI] June 6, 2013-October 6, 2013) and September 25, 2013 (95% CI May 28, 2013-January 4, 2014), suggesting that the most likely source of virus introduction was the first batch of poultry purchased in August 2013. The reassortment event that led to the human virus may have occurred between January 2, 2014 (95% CI November 8, 2013-February 12, 2014) and February 12, 2014 (95% CI January 19, 2014-February 18, 2014). Our findings demonstrate that poultry farms could be a source of reassortment between H7N9 virus and H9N2 virus as well as human infection, which emphasizes the importance to public health of active avian influenza surveillance at poultry farms. |
1,616 | Accuracy of using automated methods for detecting adverse events from electronic health record data: a research protocol | BACKGROUND: Adverse events are associated with significant morbidity, mortality and cost in hospitalized patients. Measuring adverse events is necessary for quality improvement, but current detection methods are inaccurate, untimely and expensive. The advent of electronic health records and the development of automated methods for encoding and classifying electronic narrative data, such as natural language processing, offer an opportunity to identify potentially better methods. The objective of this study is to determine the accuracy of using automated methods for detecting three highly prevalent adverse events: a) hospital-acquired pneumonia, b) catheter-associated bloodstream infections, and c) in-hospital falls. METHODS/DESIGN: This validation study will be conducted at two large Canadian academic health centres: the McGill University Health Centre (MUHC) and The Ottawa Hospital (TOH). The study population consists of all medical, surgical and intensive care unit patients admitted to these centres between 2008 and 2014. An automated detection algorithm will be developed and validated for each of the three adverse events using electronic data extracted from multiple clinical databases. A random sample of MUHC patients will be used to develop the automated detection algorithms (cohort 1, development set). The accuracy of these algorithms will be assessed using chart review as the reference standard. Then, receiver operating characteristic curves will be used to identify optimal cut points for each of the data sources. Multivariate logistic regression and the areas under curve (AUC) will be used to identify the optimal combination of data sources that maximize the accuracy of adverse event detection. The most accurate algorithms will then be validated on a second random sample of MUHC patients (cohort 1, validation set), and accuracy will be measured using chart review as the reference standard. The most accurate algorithms validated at the MUHC will then be applied to TOH data (cohort 2), and their accuracy will be assessed using a reference standard assessment of the medical chart. DISCUSSION: There is a need for more accurate, timely and efficient measures of adverse events in acute care hospitals. This is a critical requirement for evaluating the effectiveness of preventive interventions and for tracking progress in patient safety through time. |
1,617 | Animal board invited review: advances in proteomics for animal and food sciences | Animal production and health (APH) is an important sector in the world economy, representing a large proportion of the budget of all member states in the European Union and in other continents. APH is a highly competitive sector with a strong emphasis on innovation and, albeit with country to country variations, on scientific research. Proteomics (the study of all proteins present in a given tissue or fluid – i.e. the proteome) has an enormous potential when applied to APH. Nevertheless, for a variety of reasons and in contrast to disciplines such as plant sciences or human biomedicine, such potential is only now being tapped. To counter such limited usage, 6 years ago we created a consortium dedicated to the applications of Proteomics to APH, specifically in the form of a Cooperation in Science and Technology (COST) Action, termed FA1002 – Proteomics in Farm Animals: www.cost-faproteomics.org. In 4 years, the consortium quickly enlarged to a total of 31 countries in Europe, as well as Israel, Argentina, Australia and New Zealand. This article has a triple purpose. First, we aim to provide clear examples on the applications and benefits of the use of proteomics in all aspects related to APH. Second, we provide insights and possibilities on the new trends and objectives for APH proteomics applications and technologies for the years to come. Finally, we provide an overview and balance of the major activities and accomplishments of the COST Action on Farm Animal Proteomics. These include activities such as the organization of seminars, workshops and major scientific conferences, organization of summer schools, financing Short-Term Scientific Missions (STSMs) and the generation of scientific literature. Overall, the Action has attained all of the proposed objectives and has made considerable difference by putting proteomics on the global map for animal and veterinary researchers in general and by contributing significantly to reduce the East–West and North–South gaps existing in the European farm animal research. Future activities of significance in the field of scientific research, involving members of the action, as well as others, will likely be established in the future. |
1,618 | Characterizing the Transmission Dynamics and Control of Ebola Virus Disease | Carefully calibrated transmission models have the potential to guide public health officials on the nature and scale of the interventions required to control epidemics. In the context of the ongoing Ebola virus disease (EVD) epidemic in Liberia, Drake and colleagues, in this issue of PLOS Biology, employed an elegant modeling approach to capture the distributions of the number of secondary cases that arise in the community and health care settings in the context of changing population behaviors and increasing hospital capacity. Their findings underscore the role of increasing the rate of safe burials and the fractions of infectious individuals who seek hospitalization together with hospital capacity to achieve epidemic control. However, further modeling efforts of EVD transmission and control in West Africa should utilize the spatial-temporal patterns of spread in the region by incorporating spatial heterogeneity in the transmission process. Detailed datasets are urgently needed to characterize temporal changes in population behaviors, contact networks at different spatial scales, population mobility patterns, adherence to infection control measures in hospital settings, and hospitalization and reporting rates. |
1,619 | A family cluster of three confirmed cases infected with avian influenza A (H7N9) virus in Zhejiang Province of China | BACKGROUND: A total of 453 laboratory-confirmed cases infected with avian influenza A (H7N9) virus (including 175 deaths) have been reported till October 2,2014, of which 30.68% (139/453) of the cases were identified from Zhejiang Province. We describe the largest reported cluster of virologically confirmed H7N9 cases, comprised by a fatal Index case and two mild secondary cases. METHODS: A retrospective investigation was conducted in January of 2014. Three confirmed cases, their close contacts, and relevant environments samples were tested by real-time reverse transcriptase-polymerase chain reaction (RT-PCR), viral culture, and sequencing. Serum samples were tested by haemagglutination inhibition (HI) assay. RESULTS: The Index case, a 49-year-old farmer with type II diabetes, who lived with his daughter (Case 2, aged 24) and wife (Case 3, aged 43) and his son-in-law (H7N9 negative). The Index case and Case 3 worked daily in a live bird market. Onset of illness in Index case occurred in January 13, 2014 and subsequently, he died of multi-organ failure on January 20. Case 2 presented with mild symptoms on January 20 following frequent unprotected bed-side care of the Index case between January 14 to 19, and exposed to live bird market on January 17. Case 3 became unwell on January 23 after providing bedside care to the Index case on January 17 to 18, and following the contact with Case 2 during January 21 to 22 at the funeral of the Index case. The two secondary cases were discharged on February 2 and 5 separately after early treatment with antiviral medication. Four virus strains were isolated and genome analyses showed 99.6 ~100% genetic homology, with two amino mutations (V192I in NS and V280A in NP). 42% (11/26) of environmental samples collected in January were H7N9 positive. Twenty-five close contacts remained well and were negative for H7N9 infection by RT-PCR and HI assay. CONCLUSIONS: In the present study, the Index case was infected from a live bird market while the two secondary cases were infected by the Index case during unprotected exposure. This family cluster is, therefore, compatible with non-sustained person-to-person transmission of avian influenza A/H7N9. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12879-014-0698-6) contains supplementary material, which is available to authorized users. |
1,620 | A common feature pharmacophore for FDA-approved drugs inhibiting the Ebola virus | We are currently faced with a global infectious disease crisis which has been anticipated for decades. While many promising biotherapeutics are being tested, the search for a small molecule has yet to deliver an approved drug or therapeutic for the Ebola or similar filoviruses that cause haemorrhagic fever. Two recent high throughput screens published in 2013 did however identify several hits that progressed to animal studies that are FDA approved drugs used for other indications. The current computational analysis uses these molecules from two different structural classes to construct a common features pharmacophore. This ligand-based pharmacophore implicates a possible common target or mechanism that could be further explored. A recent structure based design project yielded nine co-crystal structures of pyrrolidinone inhibitors bound to the viral protein 35 (VP35). When receptor-ligand pharmacophores based on the analogs of these molecules and the protein structures were constructed, the molecular features partially overlapped with the common features of solely ligand-based pharmacophore models based on FDA approved drugs. These previously identified FDA approved drugs with activity against Ebola were therefore docked into this protein. The antimalarials chloroquine and amodiaquine docked favorably in VP35. We propose that these drugs identified to date as inhibitors of the Ebola virus may be targeting VP35. These computational models may provide preliminary insights into the molecular features that are responsible for their activity against Ebola virus in vitro and in vivo and we propose that this hypothesis could be readily tested. |
1,621 | Accounting for behavioral responses during a flu epidemic using home television viewing | BACKGROUND: Theory suggests that individual behavioral responses impact the spread of flu-like illnesses, but this has been difficult to empirically characterize. Social distancing is an important component of behavioral response, though analyses have been limited by a lack of behavioral data. Our objective is to use media data to characterize social distancing behavior in order to empirically inform explanatory and predictive epidemiological models. METHODS: We use data on variation in home television viewing as a proxy for variation in time spent in the home and, by extension, contact. This behavioral proxy is imperfect but appealing since information on a rich and representative sample is collected using consistent techniques across time and most major cities. We study the April-May 2009 outbreak of A/H1N1 in Central Mexico and examine the dynamic behavioral response in aggregate and contrast the observed patterns of various demographic subgroups. We develop and calibrate a dynamic behavioral model of disease transmission informed by the proxy data on daily variation in contact rates and compare it to a standard (non-adaptive) model and a fixed effects model that crudely captures behavior. RESULTS: We find that after a demonstrable initial behavioral response (consistent with social distancing) at the onset of the outbreak, there was attenuation in the response before the conclusion of the public health intervention. We find substantial differences in the behavioral response across age subgroups and socioeconomic levels. We also find that the dynamic behavioral and fixed effects transmission models better account for variation in new confirmed cases, generate more stable estimates of the baseline rate of transmission over time and predict the number of new cases over a short horizon with substantially less error. CONCLUSIONS: Results suggest that A/H1N1 had an innate transmission potential greater than previously thought but this was masked by behavioral responses. Observed differences in behavioral response across demographic groups indicate a potential benefit from targeting social distancing outreach efforts. |
1,622 | Therapeutic vaccination and immunomodulation in the treatment of chronic hepatitis B: preclinical studies in the woodchuck | Infection with hepatitis B virus (HBV) may lead to subclinical, acute or chronic hepatitis. In the prevaccination era, HBV infections were endemic due to frequent mother to child transmission in large regions of the world. However, there are still estimated 240 million chronic HBV carriers today and ca. 620,000 patients die per year due to HBV-related liver diseases. Recommended treatment of chronic hepatitis B with interferon-α and/or nucleos(t)ide analogues does not lead to satisfactory results. Induction of HBV-specific T cells by therapeutic vaccination or immunomodulation may be an innovative strategy to overcome virus persistence. Vaccination with commercially available HBV vaccines in patients with or without therapeutic reduction of viral load did not result in effective immune control of HBV infection, suggesting that combination of antiviral treatment with new formulations of therapeutic vaccines is needed. The woodchuck (Marmota monax) and its HBV-like woodchuck hepatitis virus are a useful preclinical animal model for developing new therapeutic approaches in chronic hepadnaviral infections. Several innovative approaches combining antiviral treatments using nucleos(t)ide analogues, with prime-boost vaccination using DNA vaccines, new hepadnaviral antigens or recombinant adenoviral vectors were tested in the woodchuck model. In this review, we summarize these encouraging results obtained with these therapeutic vaccines. In addition, we present potential innovations in immunostimulatory strategies by blocking the interaction of the inhibitory programmed death receptor 1 with its ligand in this animal model. |
1,623 | A comparison of smartphones to paper-based questionnaires for routine influenza sentinel surveillance, Kenya, 2011–2012 | BACKGROUND: For disease surveillance, manual data collection using paper-based questionnaires can be time consuming and prone to errors. We introduced smartphone data collection to replace paper-based data collection for an influenza sentinel surveillance system in four hospitals in Kenya. We compared the quality, cost and timeliness of data collection between the smartphone data collection system and the paper-based system. METHODS: Since 2006, the Kenya Ministry of Health (MoH) with technical support from the Kenya Medical Research Institute/Centers for Disease Control and Prevention (KEMRI/CDC) conducted hospital-based sentinel surveillance for influenza in Kenya. In May 2011, the MOH replaced paper-based collection with an electronic data collection system using Field Adapted Survey Toolkit (FAST) on HTC Touch Pro2 smartphones at four sentinel sites. We compared 880 paper-based questionnaires dated Jan 2010-Jun 2011 and 880 smartphone questionnaires dated May 2011-Jun 2012 from the four surveillance sites. For each site, we compared the quality, cost and timeliness of each data collection system. RESULTS: Incomplete records were more likely seen in data collected using pen-and-paper compared to data collected using smartphones (adjusted incidence rate ratio (aIRR) 7, 95% CI: 4.4-10.3). Errors and inconsistent answers were also more likely to be seen in data collected using pen-and-paper compared to data collected using smartphones (aIRR: 25, 95% CI: 12.5-51.8). Smartphone data was uploaded into the database in a median time of 7 days while paper-based data took a median of 21 days to be entered (p < 0.01). It cost USD 1,501 (9.4%) more to establish the smartphone data collection system ($17,500) than the pen-and-paper system (USD $15,999). During two years, however, the smartphone data collection system was $3,801 (7%) less expensive to operate ($50,200) when compared to pen-and-paper system ($54,001). CONCLUSIONS: Compared to paper-based data collection, an electronic data collection system produced fewer incomplete data, fewer errors and inconsistent responses and delivered data faster. Although start-up costs were higher, the overall costs of establishing and running the electronic data collection system were lower compared to paper-based data collection system. Electronic data collection using smartphones has potential to improve timeliness, data integrity and reduce costs. |
1,624 | Minimal within-host dengue models highlight the specific roles of the immune response in primary and secondary dengue infections | In recent years, the within-host viral dynamics of dengue infections have been increasingly characterized, and the relationship between aspects of these dynamics and the manifestation of severe disease has been increasingly probed. Despite this progress, there are few mathematical models of within-host dengue dynamics, and the ones that exist focus primarily on the general role of immune cells in the clearance of infected cells, while neglecting other components of the immune response in limiting viraemia. Here, by considering a suite of mathematical within-host dengue models of increasing complexity, we aim to isolate the critical components of the innate and the adaptive immune response that suffice in the reproduction of several well-characterized features of primary and secondary dengue infections. By building up from a simple target cell limited model, we show that only the innate immune response is needed to recover the characteristic features of a primary symptomatic dengue infection, while a higher rate of viral infectivity (indicative of antibody-dependent enhancement) and infected cell clearance by T cells are further needed to recover the characteristic features of a secondary dengue infection. We show that these minimal models can reproduce the increased risk of disease associated with secondary heterologous infections that arises as a result of a cytokine storm, and, further, that they are consistent with virological indicators that predict the onset of severe disease, such as the magnitude of peak viraemia, time to peak viral load, and viral clearance rate. Finally, we show that the effectiveness of these virological indicators to predict the onset of severe disease depends on the contribution of T cells in fuelling the cytokine storm. |
1,625 | HIV-1 Replication and the Cellular Eukaryotic Translation Apparatus | Eukaryotic translation is a complex process composed of three main steps: initiation, elongation, and termination. During infections by RNA- and DNA-viruses, the eukaryotic translation machinery is used to assure optimal viral protein synthesis. Human immunodeficiency virus type I (HIV-1) uses several non-canonical pathways to translate its own proteins, such as leaky scanning, frameshifting, shunt, and cap-independent mechanisms. Moreover, HIV-1 modulates the host translation machinery by targeting key translation factors and overcomes different cellular obstacles that affect protein translation. In this review, we describe how HIV-1 proteins target several components of the eukaryotic translation machinery, which consequently improves viral translation and replication. |
1,626 | Clinical vaccine development | Vaccination is regarded as one of the biggest triumphs in the history of medicine. We are living in the most successful period of vaccine development. The accumulation of multidisciplinary knowledge and the investment of massive funding have enabled the development of vaccines against many infectious diseases as well as other diseases including malignant tumors. The paradigm of clinical vaccine evaluation and licensure has also been modernized based on scientific improvements and historical experience. However, there remain a number of hurdles to overcome. Continuous efforts are focused on increasing the efficacy and reducing the risks related to vaccine use. Cutting-edge knowledge about immunology and microbiology is being rapidly translated to vaccine development. Thus, physicians and others involved in the clinical development of vaccines should have sufficient understanding of the recent developmental trends in vaccination and the diseases of interest. |
1,627 | Influenza D Virus in Cattle, France, 2011–2014 | A new influenza virus, genus D, isolated in US pigs and cattle, has also been circulating in cattle in France. It was first identified there in 2011, and an increase was detected in 2014. The virus genome in France is 94%–99% identical to its US counterpart, which suggests intercontinental spillover. |
1,628 | Exploration of diarrhoea seasonality and its drivers in China | This study investigated the diarrhoea seasonality and its potential drivers as well as potential opportunities for future diarrhoea control and prevention in China. Data on weekly infectious diarrhoea cases in 31 provinces of China from 2005 to 2012, and data on demographic and geographic characteristics, as well as climatic factors, were complied. A cosinor function combined with a Poisson regression was used to calculate the three seasonal parameters of diarrhoea in different provinces. Regression tree analysis was used to identify the predictors of diarrhoea seasonality. Diarrhoea cases in China showed a bimodal distribution. Diarrhoea in children <5 years was more likely to peak in fall-winter seasons, while diarrhoea in persons > = 5 years peaked in summer. Latitude was significantly associated with spatial pattern of diarrhoea seasonality, with peak and trough times occurring earlier at high latitudes (northern areas), and later at low latitudes (southern areas). The annual amplitudes of diarrhoea in persons > = 5 years increased with latitude (r = 0.62, P<0.001). Latitude 27.8° N and 38.65° N were the latitudinal thresholds for diarrhoea seasonality in China. Regional-specific diarrhoea control and prevention strategies may be optimal for China. More attention should be paid to diarrhoea in children <5 years during fall-winter seasons. |
1,629 | Resistance Prediction in AML: Analysis of 4,601 Patients from MRC/NCRI, HOVON/SAKK, SWOG, and MD Anderson Cancer Center | Therapeutic resistance remains the principal problem in acute myeloid leukemia (AML). We used area under receiver operator characteristic curves (AUC) to quantify our ability to predict therapeutic resistance in individual patients where AUC=1.0 denotes perfect prediction and AUC=0.5 denotes a coin flip, using data from 4,601 patients with newly diagnosed AML given induction therapy with 3+7 or more intense standard regimens in MRC/NCRI, HOVON, SWOG, and MD Anderson Cancer Center studies. Age, performance status, white blood cell count, secondary disease, cytogenetic risk, and FLT3-ITD/NPM1 mutation status were each independently associated with failure to achieve complete remission despite no early death (“primary refractoriness”). However, the AUC of a bootstrap-corrected multivariable model predicting this outcome was only 0.78, indicating only fair predictive ability. Removal of FLT3-ITD and NPM1 information only slightly decreased the AUC (0.76). Prediction of resistance, defined as primary refractoriness or short relapse-free survival (RFS), was even more difficult. Our ability to forecast resistance based on routinely available pre-treatment covariates provides a rationale for continued randomization between standard and new therapies and supports further examination of genetic and post-treatment data to optimize resistance prediction in AML. |
1,630 | AS03(B)-Adjuvanted H5N1 Influenza Vaccine in Children 6 Months Through 17 Years of Age: A Phase 2/3 Randomized, Placebo-Controlled, Observer-Blinded Trial | Background. This phase 2/3, randomized, placebo-controlled, observer-blinded study assessed the immunogenicity, reactogenicity, and safety of an inactivated, split-virion H5N1 influenza vaccine (A/Indonesia/5/2005) in children aged 6 months through 17 years. Methods. Children received 2 influenza vaccine doses 21 days apart, each containing 1.9 µg of hemagglutinin and AS03(B) adjuvant (5.93 mg of α-tocopherol). The randomization ratio was 8:3 for vaccine to placebo, with equal allocation between 3 age strata (6–35 months, 3–8 years, and 9–17 years). Immunogenicity against the vaccine strain was assessed 21 days after the first and second vaccine doses for all vaccinees, at day 182 for half, and at day 385 for the remaining half. Reactogenicity after each dose and safety up to 1 year after vaccination were evaluated. Results. Within each age stratum, the lower limit of the 98.3% confidence interval for the day 42 seroprotection rate was ≥70%, thus fulfilling the US and European licensure criteria. The immune responses elicited by vaccine persisted well above baseline levels for 1 year. The vaccine was more reactogenic than placebo, but no major safety concerns were identified. Conclusions. AS03(B)-adjuvanted H5N1 influenza vaccine was immunogenic and showed an acceptable safety profile in all age groups studied. Clinical Trials Registration. NCT01310413. |
1,631 | In Vitro Bactericidal Activity of 4- and 5-Chloro-2-hydroxy-N-[1-oxo-1-(phenylamino)alkan-2-yl]benzamides against MRSA | A series of nine substituted 2-hydroxy-N-[1-oxo-1-(phenylamino)alkan-2-yl]benzamides was assessed as prospective bactericidal agents against three clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus ATCC 29213 as the reference and quality control strain. The minimum bactericidal concentration was determined by subculturing aliquots from MIC determination onto substance-free agar plates. The bactericidal kinetics of compounds 5-chloro-2-hydroxy-N-[(2S)-3-methyl-1-oxo-1-{[4-(trifluoromethyl)phenyl]amino}butan-2-yl]benzamide (1f), N-{(2S)-1-[(4-bromophenyl)amino]-3-methyl-1-oxobutan-2-yl}-4-chloro-2-hydroxybenzamide (1g), and 4-chloro-N-{(2S)-1-[(3,4-dichlorophenyl)amino]-3-methyl-1-oxobutan-2-yl}-2-hydroxybenzamide (1h) was established by time-kill assay with a final concentration of the compound equal to 1x, 2x, and 4x MIC; aliquots were removed at 0, 4, 6, 8, and 24 h time points. The most potent bactericidal agent was compound 1f exhibiting remarkable rapid concentration-dependent bactericidal effect even at 2x MIC at 4, 6, and 8 h (with a reduction in bacterial count ranging from 3.08 to 3.75 log(10) CFU/mL) and at 4x MIC at 4, 6, 8, and 24 h (5.30 log(10) CFU/mL reduction in bacterial count) after incubation against MRSA 63718. Reliable bactericidal effect against other strains was maintained at 4x MIC at 24 h. |
1,632 | A co-culture genome-wide RNAi screen with mammary epithelial cells reveals transmembrane signals required for growth and differentiation | INTRODUCTION: The extracellular signals regulating mammary epithelial cell growth are of relevance to understanding the pathophysiology of mammary epithelia, yet they remain poorly characterized. In this study, we applied an unbiased approach to understanding the functional role of signalling molecules in several models of normal physiological growth and translated these results to the biological understanding of breast cancer subtypes. METHODS: We developed and utilized a cytogenetically normal clonal line of hTERT immortalized human mammary epithelial cells in a fibroblast-enhanced co-culture assay to conduct a genome-wide small interfering RNA (siRNA) screen for evaluation of the functional effect of silencing each gene. Our selected endpoint was inhibition of growth. In rigorous postscreen validation processes, including quantitative RT-PCR, to ensure on-target silencing, deconvolution of pooled siRNAs and independent confirmation of effects with lentiviral short-hairpin RNA constructs, we identified a subset of genes required for mammary epithelial cell growth. Using three-dimensional Matrigel growth and differentiation assays and primary human mammary epithelial cell colony assays, we confirmed that these growth effects were not limited to the 184-hTERT cell line. We utilized the METABRIC dataset of 1,998 breast cancer patients to evaluate both the differential expression of these genes across breast cancer subtypes and their prognostic significance. RESULTS: We identified 47 genes that are critically important for fibroblast-enhanced mammary epithelial cell growth. This group was enriched for several axonal guidance molecules and G protein–coupled receptors, as well as for the endothelin receptor PROCR. The majority of genes (43 of 47) identified in two dimensions were also required for three-dimensional growth, with HSD17B2, SNN and PROCR showing greater than tenfold reductions in acinar formation. Several genes, including PROCR and the neuronal pathfinding molecules EFNA4 and NTN1, were also required for proper differentiation and polarization in three-dimensional cultures. The 47 genes identified showed a significant nonrandom enrichment for differential expression among 10 molecular subtypes of breast cancer sampled from 1,998 patients. CD79A, SERPINH1, KCNJ5 and TMEM14C exhibited breast cancer subtype–independent overall survival differences. CONCLUSION: Diverse transmembrane signals are required for mammary epithelial cell growth in two-dimensional and three-dimensional conditions. Strikingly, we define novel roles for axonal pathfinding receptors and ligands and the endothelin receptor in both growth and differentiation. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13058-014-0510-y) contains supplementary material, which is available to authorized users. |
1,633 | Point-of-Use Mixing of Influenza H5N1 Vaccine and MF59 Adjuvant for Pandemic Vaccination Preparedness: Antibody Responses and Safety. A Phase 1 Clinical Trial | BACKGROUND: Avian influenza A/H5N1 has threatened human health for nearly 2 decades. Avian influenza A vaccine without adjuvant is poorly immunogenic. A flexible rapid tactic for mass vaccination will be needed if a pandemic occurs. METHODS: A multicenter, randomized, blinded phase 1 clinical trial evaluated safety and antibody responses after point-of-use mixing of influenza A/Indonesia/05/2005 (H5N1) vaccine with MF59 adjuvant. Field-site pharmacies mixed 3.75, 7.5, or 15 mcg of antigen with or without MF59 adjuvant just prior to intramuscular administration on days 0 and 21 of healthy adults aged 18–49 years. RESULTS: Two hundred and seventy subjects were enrolled. After vaccination, titers of hemagglutination inhibition antibody ≥1:40 were achieved in 80% of subjects receiving 3.75 mcg + MF59 vs only 14% receiving 15 mcg without adjuvant (P < .0001). Peak hemagglutination inhibition antibody geometric mean titers for vaccine + MF59 were ∼65 regardless of antigen dose, and neutralizing titers were 2- to 3-fold higher. Vaccine + MF59 produced cross-reactive antibody responses against 4 heterologous H5N1 viruses. Excellent safety and tolerability were demonstrated. CONCLUSIONS: Point-of-use mixing of H5N1 antigen and MF59 adjuvant achieved target antibody titers in a high percentage of subjects and was safe. The feasibility of the point-of-use mixing should be studied further. |
1,634 | Safety, Reactogenicity, and Immunogenicity of Inactivated Monovalent Influenza A(H5N1) Virus Vaccine Administered With or Without AS03 Adjuvant | BACKGROUND: The national stockpile for influenza pandemic preparedness includes vaccines against an array of strains and adjuvants that could be utilized to induce immunologic priming as a pandemic wave emerges. We assessed the feasibility of a strategy that allows the flexibility of postmanufacture mixture of vaccine and adjuvant at the point of care. METHODS: We conducted a randomized, double-blind, multicenter trial among healthy adults aged 18–49 years who received 2 doses of inactivated influenza A/Indonesia/05/2005 (H5N1 clade 2.2.3) virus vaccine containing either 3.75, 7.5, or 15 µg of hemagglutinin (HA) with or without AS03 adjuvant, administered 21 days apart. Subjects were observed for local (injection site) and systemic reactogenicity and adverse events. Sera were tested for hemagglutination inhibition (HAI) and microneutralization (MN) antibody levels against the homologous strain and 4 heterologous avian strains. RESULTS: Vaccine containing ASO3 adjuvant was associated with significantly more local reactions compared with nonadjuvanted vaccine, but these were short-lived and resolved spontaneously. Although the immune response to nonadjuvanted vaccine was poor, 2 doses of AS03-adjuvanted vaccine containing as little as 3.75 µg of HA elicited robust immune responses resulting in seroprotective titers (≥1:40) to the homologous strain in ≥86% of subjects by HAI and in 95% of subjects by MN. Cross-clade antibody responses were also observed with AS03-adjuvanted vaccine, but not nonadjuvanted vaccine. CONCLUSIONS: AS03 adjuvant formulated with inactivated vaccine at the administration site significantly enhanced the immune responses to H5N1 vaccine and has the potential to markedly improve vaccine responses and accelerate delivery during an influenza pandemic. CLINICAL TRIALS REGISTRATION: NCT01317758. |
1,635 | Nelfinavir Impairs Glycosylation of Herpes Simplex Virus 1 Envelope Proteins and Blocks Virus Maturation | Nelfinavir (NFV) is an HIV-1 aspartyl protease inhibitor that has numerous effects on human cells, which impart attractive antitumor properties. NFV has also been shown to have in vitro inhibitory activity against human herpesviruses (HHVs). Given the apparent absence of an aspartyl protease encoded by HHVs, we investigated the mechanism of action of NFV herpes simplex virus type 1 (HSV-1) in cultured cells. Selection of HSV-1 resistance to NFV was not achieved despite multiple passages under drug pressure. NFV did not significantly affect the level of expression of late HSV-1 gene products. Normal numbers of viral particles appeared to be produced in NFV-treated cells by electron microscopy but remain within the cytoplasm more often than controls. NFV did not inhibit the activity of the HSV-1 serine protease nor could its antiviral activity be attributed to inhibition of Akt phosphorylation. NFV was found to decrease glycosylation of viral glycoproteins B and C and resulted in aberrant subcellular localization, consistent with induction of endoplasmic reticulum stress and the unfolded protein response by NFV. These results demonstrate that NFV causes alterations in HSV-1 glycoprotein maturation and egress and likely acts on one or more host cell functions that are important for HHV replication. |
1,636 | IFNL4 and IFNL3 Associated Polymorphisms Strongly Influence the Spontaneous IFN-Alpha Receptor-1 Expression in HCV-Infected Patients | Single-nucleotide polymorphism in IFNL3 gene (rs12979860) predicts spontaneous and therapy-induced HCV clearance. In a previous study from our group PBMC from patients with favourable rs12979860 genotype showed higher levels of IFNAR-1 mRNA. Recently, a dinucleotide polymorphism, ss469415590 (TT or ΔG), has been discovered in the region upstream IFNL3 gene, which is in high linkage disequilibrium with rs12979860. ss469415590[ΔG] is a frameshift variant that creates a novel gene, designed IFNL4, encoding the interferon-lambda 4 protein (IFNL4). The aim of the present study was to extend the analysis of IFNAR-1 mRNA levels to the ss469415590 variants. Our results highlight that the difference of IFNAR-1 mRNA levels between favourable and unfavourable genotype combinations, at both rs12979860 and ss469415590 loci, is stronger than that observed for single polymorphisms at each locus. These findings suggest may represent the biological basis for the observed association between IFNL3 CC and IFNL4 TT/TT genotypes and favourable outcome of either natural HCV infection (clearance vs chronic evolution) or IFN-based therapy. |
1,637 | Conformational B-Cell Epitope Prediction Method Based on Antigen Preprocessing and Mimotopes Analysis | Identification of epitopes which invokes strong humoral responses is an essential issue in the field of immunology. Various computational methods that have been developed based on the antigen structures and the mimotopes these years narrow the search for experimental validation. These methods can be divided into two categories: antigen structure-based methods and mimotope-based methods. Though new methods of the two kinds have been proposed in these years, they cannot maintain a high degree of satisfaction in various circumstances. In this paper, we proposed a new conformational B-cell epitope prediction method based on antigen preprocessing and mimotopes analysis. The method classifies the antigen surface residues into “epitopes” and “nonepitopes” by six epitope propensity scales, removing the “nonepitopes” and using the preprocessed antigen for epitope prediction based on mimotope sequences. The proposed method gives out the mean F score of 0.42 on the testing dataset. When compared with other publicly available servers by using the testing dataset, the new method yields better performance. The results demonstrate the proposed method is competent for the conformational B-cell epitope prediction. |
1,638 | RPI-Pred: predicting ncRNA-protein interaction using sequence and structural information | RNA-protein complexes are essential in mediating important fundamental cellular processes, such as transport and localization. In particular, ncRNA-protein interactions play an important role in post-transcriptional gene regulation like mRNA localization, mRNA stabilization, poly-adenylation, splicing and translation. The experimental methods to solve RNA-protein interaction prediction problem remain expensive and time-consuming. Here, we present the RPI-Pred (RNA-protein interaction predictor), a new support-vector machine-based method, to predict protein-RNA interaction pairs, based on both the sequences and structures. The results show that RPI-Pred can correctly predict RNA-protein interaction pairs with ∼94% prediction accuracy when using sequence and experimentally determined protein and RNA structures, and with ∼83% when using sequences and predicted protein and RNA structures. Further, our proposed method RPI-Pred was superior to other existing ones by predicting more experimentally validated ncRNA-protein interaction pairs from different organisms. Motivated by the improved performance of RPI-Pred, we further applied our method for reliable construction of ncRNA-protein interaction networks. The RPI-Pred is publicly available at: http://ctsb.is.wfubmc.edu/projects/rpi-pred. |
1,639 | Year in review 2013: critical care - respiratory infections | Infectious complications, particularly in the respiratory tract of critically ill patients, are related to increased mortality. Severe infection is part of a multiple system illness and female patients with severe sepsis have a worse prognosis compared to males. Kallistatin is a protective hormokine released during monocyte activation and low levels in the setting of septic shock can predict adverse outcomes. Presepsin is another biomarker that was recently evaluated and is elevated in patients with severe sepsis patients at risk of dying. The Centers for Disease Control and Prevention has introduced new definitions for identifying patients at risk of ventilator-associated complications (VACs), but several other conditions, such as pulmonary edema and acute respiratory distress syndrome, may cause VACs, and not all patients with VACs may have ventilator-associated pneumonia. New studies have suggested strategies to identify patients at risk for resistant pathogen infection and therapies that optimize efficacy, without the overuse of broad-spectrum therapy in patients with healthcare-associated pneumonia. Innovative strategies using optimized dosing of antimicrobials, maximizing the pharmacokinetic and pharmacodynamic properties of drugs in critically ill patients, and newer routes of drug delivery are being explored to combat drug-resistant pathogens. We summarize the major clinical studies on respiratory infections in critically ill patients published in 2013. |
1,640 | Genomic Characterization of Novel Circular ssDNA Viruses from Insectivorous Bats in Southern Brazil | Circoviruses are highly prevalent porcine and avian pathogens. In recent years, novel circular ssDNA genomes have recently been detected in a variety of fecal and environmental samples using deep sequencing approaches. In this study the identification of genomes of novel circoviruses and cycloviruses in feces of insectivorous bats is reported. Pan-reactive primers were used targeting the conserved rep region of circoviruses and cycloviruses to screen DNA bat fecal samples. Using this approach, partial rep sequences were detected which formed five phylogenetic groups distributed among the Circovirus and the recently proposed Cyclovirus genera of the Circoviridae. Further analysis using inverse PCR and Sanger sequencing led to the characterization of four new putative members of the family Circoviridae with genome size ranging from 1,608 to 1,790 nt, two inversely arranged ORFs, and canonical nonamer sequences atop a stem loop. |
1,641 | Fatal outcome of human influenza A (H5N1) is associated with high viral load and hypercytokinemia | Avian influenza A (H5N1) viruses cause severe disease in humans(1,2), but the basis for their virulence remains unclear. In vitro and animal studies indicate that high and disseminated viral replication is important for disease pathogenesis(3,4,5). Laboratory experiments suggest that virus-induced cytokine dysregulation may contribute to disease severity(6,7,8,9). To assess the relevance of these findings for human disease, we performed virological and immunological studies in 18 individuals with H5N1 and 8 individuals infected with human influenza virus subtypes. Influenza H5N1 infection in humans is characterized by high pharyngeal virus loads and frequent detection of viral RNA in rectum and blood. Viral RNA in blood was present only in fatal H5N1 cases and was associated with higher pharyngeal viral loads. We observed low peripheral blood T-lymphocyte counts and high chemokine and cytokine levels in H5N1-infected individuals, particularly in those who died, and these correlated with pharyngeal viral loads. Genetic characterization of H5N1 viruses revealed mutations in the viral polymerase complex associated with mammalian adaptation and virulence. Our observations indicate that high viral load, and the resulting intense inflammatory responses, are central to influenza H5N1 pathogenesis. The focus of clinical management should be on preventing this intense cytokine response, by early diagnosis and effective antiviral treatment. SUPPLEMENTARY INFORMATION: The online version of this article (doi:10.1038/nm1477) contains supplementary material, which is available to authorized users. |
1,642 | Resveratrol Inhibits Enterovirus 71 Replication and Pro-Inflammatory Cytokine Secretion in Rhabdosarcoma Cells through Blocking IKKs/NF-κB Signaling Pathway | Polydatin and resveratrol, as major active components in Polygonum cuspidatum, have anti-inflammatory, antioxidant and antitumor functions. However, the effect and mechanism of polydatin and resveratrol on enterovirus 71 (EV71) have not been reported. In this study, resveratrol revealed strong antiviral activity on EV71, while polydatin had weak effect. Neither polydatin nor resveratrol exhibited influence on viral attachment. Resveratrol could effectively inhibit the synthesis of EV71/VP1 and the phosphorylation of IKKα, IKKβ, IKKγ, IKBα, NF-κB p50 and NF-κB p65, respectively. Meanwhile, the remarkably increased secretion of IL-6 and TNF-α in EV71-infected rhabdosarcoma (RD) cells could be blocked by resveratrol. These results demonstrated that resveratrol inhibited EV71 replication and cytokine secretion in EV71-infected RD cells through blocking IKKs/NF-κB signaling pathway. Thus, resveratrol may have potent antiviral effect on EV71 infection. |
1,643 | Unrealistic Optimism, Sex, and Risk Perception of Type 2 Diabetes Onset: Implications for Education Programs | This study examined links among unrealistic optimism, sex, and risk perception of type 2 diabetes onset in college students. Participants included 660 college students who consented to complete a questionnaire. The results showed significant differences between students who perceived that they were at risk for type 2 diabetes onset and those who thought their peers were the ones at risk. A higher prevalence of participants thought their peers were the ones at risk for type 2 diabetes. Women were more likely than men to report a higher risk perception, indicating that their peers were at lower risk for diabetes onset. |
1,644 | Evolution of Genome Size and Complexity in the Rhabdoviridae | RNA viruses exhibit substantial structural, ecological and genomic diversity. However, genome size in RNA viruses is likely limited by a high mutation rate, resulting in the evolution of various mechanisms to increase complexity while minimising genome expansion. Here we conduct a large-scale analysis of the genome sequences of 99 animal rhabdoviruses, including 45 genomes which we determined de novo, to identify patterns of genome expansion and the evolution of genome complexity. All but seven of the rhabdoviruses clustered into 17 well-supported monophyletic groups, of which eight corresponded to established genera, seven were assigned as new genera, and two were taxonomically ambiguous. We show that the acquisition and loss of new genes appears to have been a central theme of rhabdovirus evolution, and has been associated with the appearance of alternative, overlapping and consecutive ORFs within the major structural protein genes, and the insertion and loss of additional ORFs in each gene junction in a clade-specific manner. Changes in the lengths of gene junctions accounted for as much as 48.5% of the variation in genome size from the smallest to the largest genome, and the frequency with which new ORFs were observed increased in the 3’ to 5’ direction along the genome. We also identify several new families of accessory genes encoded in these regions, and show that non-canonical expression strategies involving TURBS-like termination-reinitiation, ribosomal frame-shifts and leaky ribosomal scanning appear to be common. We conclude that rhabdoviruses have an unusual capacity for genomic plasticity that may be linked to their discontinuous transcription strategy from the negative-sense single-stranded RNA genome, and propose a model that accounts for the regular occurrence of genome expansion and contraction throughout the evolution of the Rhabdoviridae. |
1,645 | Human Ebola virus infection in West Africa: a review of available therapeutic agents that target different steps of the life cycle of Ebola virus | The recent outbreak of the human Zaire ebolavirus (EBOV) epidemic is spiraling out of control in West Africa. Human EBOV hemorrhagic fever has a case fatality rate of up to 90%. The EBOV is classified as a biosafety level 4 pathogen and is considered a category A agent of bioterrorism by Centers for Disease Control and Prevention, with no approved therapies and vaccines available for its treatment apart from supportive care. Although several promising therapeutic agents and vaccines against EBOV are undergoing the Phase I human trial, the current epidemic might be outpacing the speed at which drugs and vaccines can be produced. Like all viruses, the EBOV largely relies on host cell factors and physiological processes for its entry, replication, and egress. We have reviewed currently available therapeutic agents that have been shown to be effective in suppressing the proliferation of the EBOV in cell cultures or animal studies. Most of the therapeutic agents in this review are directed against non-mutable targets of the host, which is independent of viral mutation. These medications are approved by the Food and Drug Administration (FDA) for the treatment of other diseases. They are available and stockpileable for immediate use. They may also have a complementary role to those therapeutic agents under development that are directed against the mutable targets of the EBOV. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/2049-9957-3-43) contains supplementary material, which is available to authorized users. |
1,646 | Inaugural editorial: Military Medical Research | Military medicine is one of the most innovative part of human civilization. Along with the rapid development of medicine and advances in military techniques, military medicine has become the focus and intersection of new knowledge and new technologies. Innovation and development within military medicine are always ongoing, with a long and challenging path ahead. The establishment of “Military Medical Research” is expected to be a bounden responsibility in the frontline of Chinese military medicine. |
1,647 | Military medicine in China: old topic, new concept | Military medicine is important in both war and peace. In China, military medicine plays a key role in supporting and maintaining health, in preventing injuries and diseases in military staff and in enhancing the military armed forces during war. Additionally, military medicine participates in actions such as emergency public health crises, natural disasters, emerging conflicts and anti-terrorist campaigns during peacetime. In this paper, we summary the current condition and achievements in military medicine in China and provide our perspective for its future. |
1,648 | Effects of Storage Time on Total Protein and Globulin Concentrations in Bovine Fresh Frozen Plasma Obtained for Transfusion | To evaluate the effects of storage conditions on total protein (TP) and globulin fractions in fresh frozen bovine plasma units prepared and stored for transfusion, TP and globulin fractions were evaluated in fresh plasma and at 1 month and 6 and 12 months after blood collection in plasma stored at −20°C. Significant differences in concentrations were found in the median concentration of total protein (P = 0.0336), between 0 months and 1 month (P = 0.0108), 0 and 6 months (P = 0.0023), and 0 and 12 months (P = 0.0027), in mean concentration (g/dL) of albumin (P = 0.0394), between 0 months and 1 month (P = 0.0131), 0 and 6 months (P = 0.0035), and 0 and 12 months (P = 0.0038), and beta-2 fraction (P = 0.0401), between 0 and 6 months (P = 0.0401) and 0 and 12 months (P = 0.0230). This study suggests that total gamma globulin concentration in bovine frozen plasma is stable for 12 months at −20°C. Total protein, ALB, and beta-2 fraction have significantly different concentrations (g/dL) when compared to prestorage. This study has shown IgG protein fraction stability in bovine fresh frozen plasma collected for transfusion; therefore, bovine fresh frozen plasma seems to be suitable for the treatment of hypogammaglobulinemia (failure of passive transfer) in calves when stored for 12 months at −20°C. |
1,649 | Virus-Like Particles Activate Type I Interferon Pathways to Facilitate Post-Exposure Protection against Ebola Virus Infection | Ebola virus (EBOV) causes a severe hemorrhagic disease with high fatality. Virus-like particles (VLPs) are a promising vaccine candidate against EBOV. We recently showed that VLPs protect mice from lethal EBOV infection when given before or after viral infection. To elucidate pathways through which VLPs confer post-exposure protection, we investigated the role of type I interferon (IFN) signaling. We found that VLPs lead to accelerated induction of IFN stimulated genes (ISGs) in liver and spleen of wild type mice, but not in Ifnar(-/-) mice. Accordingly, EBOV infected Ifnar(-/-) mice, unlike wild type mice succumbed to death even after VLP treatment. The ISGs induced in wild type mice included anti-viral proteins and negative feedback factors known to restrict viral replication and excessive inflammatory responses. Importantly, proinflammatory cytokine/chemokine expression was much higher in WT mice without VLPs than mice treated with VLPs. In EBOV infected Ifnar(-/-) mice, however, uninhibited viral replication and elevated proinflammatory factor expression ensued, irrespective of VLP treatment, supporting the view that type I IFN signaling helps to limit viral replication and attenuate inflammatory responses. Further analyses showed that VLP protection requires the transcription factor, IRF8 known to amplify type I IFN signaling in dendritic cells and macrophages, the probable sites of initial EBOV infection. Together, this study indicates that VLPs afford post-exposure protection by promoting expeditious initiation of type I IFN signaling in the host. |
1,650 | New Insights into Flavivirus Evolution, Taxonomy and Biogeographic History, Extended by Analysis of Canonical and Alternative Coding Sequences | To generate the most diverse phylogenetic dataset for the flaviviruses to date, we determined the genomic sequences and phylogenetic relationships of 14 flaviviruses, of which 10 are primarily associated with Culex spp. mosquitoes. We analyze these data, in conjunction with a comprehensive collection of flavivirus genomes, to characterize flavivirus evolutionary and biogeographic history in unprecedented detail and breadth. Based on the presumed introduction of yellow fever virus into the Americas via the transatlantic slave trade, we extrapolated a timescale for a relevant subset of flaviviruses whose evolutionary history, shows that different Culex-spp. associated flaviviruses have been introduced from the Old World to the New World on at least five separate occasions, with 2 different sets of factors likely to have contributed to the dispersal of the different viruses. We also discuss the significance of programmed ribosomal frameshifting in a central region of the polyprotein open reading frame in some mosquito-associated flaviviruses. |
1,651 | Knowledge, Attitudes, and Practices Regarding Avian Influenza A (H7N9) Among Mobile Phone Users: A Survey in Zhejiang Province, China | BACKGROUND: Understanding people’s knowledge, attitudes, and practices (KAP) regarding a new infectious disease is crucial to the prevention and control of it. Human infection with avian influenza A (H7N9) was first identified on March 31, 2013 in China. Out of the total number of 134 cases confirmed from March to September 2013 in China, Zhejiang Province saw the greatest number (46 cases). OBJECTIVE: This study employed a mobile Internet survey to assess KAP regarding H7N9 among mobile phone users in Zhejiang Province. This study intended to examine KAP by region and the association between sociodemographic variables and KAP. METHODS: An anonymous questionnaire was designed by Zhejiang Provincial Center for Disease Control and Prevention (CDC). A cross-sectional survey was executed through a mobile Internet application platform of China Unicom in 5 regions in Zhejiang Province. Stratified and clustered sampling methods were applied and mobile phone users were invited to participate in the study voluntarily. RESULTS: A total of 9582 eligible mobile phone users participated in the survey with a response rate of 1.92% (9582/5,000,000). A total of 9105 valid responses (95.02%) were included for statistical analysis. Generally, more than three-quarters of the participants had some basic knowledge of H7N9 and held the attitude recommended by the Zhejiang CDC toward eating cooked poultry (77.55%, 7061/9105) and visiting a hospital at the occurrence of symptoms (78.51%, 7148/9105). Approximately half of the participants worried about contracting H7N9, and took preventive practices recommended by the Zhejiang CDC. But only 14.29% (1301/9105) of participants kept eating cooked poultry as usual. Although worry about H7N9 infection did not differ by region, Hangzhou saw the largest proportion of participants with knowledge of H7N9, which was probably because Hangzhou had the greatest number of H7N9 cases. KAP varied by some sociodemographic variables. Female participants were more likely to know about symptoms of H7N9 (OR 1.32, 95% CI 1.08-1.61), to worry about contracting it (OR 1.15, 95% CI 1.04-1.27), and to report their lives being influenced by it (OR 1.27, 95% CI 1.15-1.41). They were also more likely to take the recommended precautions. Male participants and younger participants were less likely to comply with advocated protective practices. CONCLUSIONS: The results suggest that health education should be customized depending on sociodemographic variables to achieve more effective behavioral outcomes. |
1,652 | A Bayesian Inferential Approach to Quantify the Transmission Intensity of Disease Outbreak | Background. Emergence of infectious diseases like influenza pandemic (H1N1) 2009 has become great concern, which posed new challenges to the health authorities worldwide. To control these diseases various studies have been developed in the field of mathematical modelling, which is useful tool for understanding the epidemiological dynamics and their dependence on social mixing patterns. Method. We have used Bayesian approach to quantify the disease outbreak through key epidemiological parameter basic reproduction number (R (0)), using effective contacts, defined as sum of the product of incidence cases and probability of generation time distribution. We have estimated R (0) from daily case incidence data for pandemic influenza A/H1N1 2009 in India, for the initial phase. Result. The estimated R (0) with 95% credible interval is consistent with several other studies on the same strain. Through sensitivity analysis our study indicates that infectiousness affects the estimate of R (0). Conclusion. Basic reproduction number R (0) provides the useful information to the public health system to do some effort in controlling the disease by using mitigation strategies like vaccination, quarantine, and so forth. |
1,653 | CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production | B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1(−/−) mice limits the survival of B cells. During systemic infection with cytopathic vesicular stomatitis virus, Ceacam1(−/−) mice can barely induce neutralizing antibody responses and die early after infection. We find, therefore, that CEACAM1 is a crucial regulator of B-cell survival, influencing B-cell numbers and protective antiviral antibody responses. |
1,654 | Innate Immune Sensing and Response to Influenza | Influenza viruses pose a substantial threat to human and animal health worldwide. Recent studies in mouse models have revealed an indispensable role for the innate immune system in defense against influenza virus. Recognition of the virus by innate immune receptors in a multitude of cell types activates intricate signaling networks, functioning to restrict viral replication. Downstream effector mechanisms include activation of innate immune cells and, induction and regulation of adaptive immunity. However, uncontrolled innate responses are associated with exaggerated disease, especially in pandemic influenza virus infection. Despite advances in the understanding of innate response to influenza in the mouse model, there is a large knowledge gap in humans, particularly in immunocompromised groups such as infants and the elderly. We propose here, the need for further studies in humans to decipher the role of innate immunity to influenza virus, particularly at the site of infection. These studies will complement the existing work in mice and facilitate the quest to design improved vaccines and therapeutic strategies against influenza. |
1,655 | Detection of rickettsial DNA in ticks and wild boars in Kyoto City, Japan | The tick is a well-known vector for arthropod-borne pathogens, such as tick-borne encephalitis, Lyme disease, Japanese spotted fever and severe fever with thrombocytopenia syndrome. It is therefore important to know the tick population and distribution in our environment and wild animals in order to prevent tick-borne diseases. Here, we report the results of tick surveillance from May to September 2011 at 14 geographical points and in 5 wild boars in Kyoto City, Kyoto prefecture, Japan. We collected 3,198 ticks comprising 5 tick species, Haemaphysalis (H.) longicornis, H. flava, H. kitaokai, Amblyomma testudinarium and Dermacentor taiwanensis. Interestingly, the proportion of tick species varied according to geographical region within the city. The ticks collected in the city were reported as potential vectors of pathogens, such as rickettsiosis. We detected rickettsial DNA by PCR in 71.1% of 201 ticks investigated. The ticks that carried rickettsiae were distributed across the whole the city. The sequences of PCR-amplified DNA fragments were determined and showed similarities to spotted fever group rickettsiae. Although their pathogenicity for animals including humans is still unclear, it is important to stay alert and pay attention to tick-borne diseases in order to ensure the safety of the citizens of the city as well as that of visitors. |
1,656 | Do corticosteroids reduce the mortality of influenza A (H1N1) infection? A meta-analysis | INTRODUCTION: Corticosteroids are used empirically in influenza A (H1N1) treatment despite lack of clear evidence for effective treatment. This study aims to assess the efficacy of corticosteroids treatment for H1N1 infection. METHODS: Systematic review and meta-analysis were used to estimate the efficacy of corticosteroids for the prevention of mortality in H1N1 infection. Databases searched included MEDLINE, EMBASE, PubMed, Cochrane Central Register of Controlled Clinical Trials and so on, and bibliographies of retrieved articles, from April 2009 to October 2014. We included both cohort studies and case-control studies reported in English or Chinese that compared treatment effects between corticosteroids and non-corticosteroids therapy in inpatients with H1N1 virus infection. Cohort studies employed mortality as outcome, and case-control studies employed deaths as cases and survivors as controls; both were assessed in this meta-analysis. RESULTS: In total twenty-three eligible studies were included. Both cohort studies (nine studies, n = 1,405) and case-control studies (14 studies, n = 4,700) showed a similar trend toward increased mortality (cohort studies relative risk was 1.85 with 95% confidence interval (CI) 1.46 to 2.33; case-control studies odds ratio was 4.22 with 95% CI 3.10 to 5.76). The results from both subgroup analyses and sensitive analyses were consistent with each other, showing that steroid treatment is associated with mortality. However, considering the fact that corticosteroids were tend to be used in sickest case-patients and heterogeneity was observed between studies, we cannot make a solid conclusion. CONCLUSIONS: Available evidence did not support the use of corticosteroids as standard care for patients with severe influenza. We conclude that further research is required. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13054-015-0764-5) contains supplementary material, which is available to authorized users. |
1,657 | Structure determination of Murine Norovirus NS6 proteases with C-terminal extensions designed to probe protease–substrate interactions | Noroviruses are positive-sense single-stranded RNA viruses. They encode an NS6 protease that cleaves a viral polyprotein at specific sites to produce mature viral proteins. In an earlier study we obtained crystals of murine norovirus (MNV) NS6 protease in which crystal contacts were mediated by specific insertion of the C-terminus of one protein (which contains residues P5-P1 of the NS6-7 cleavage junction) into the peptide binding site of an adjacent molecule, forming an adventitious protease-product complex. We sought to reproduce this crystal form to investigate protease–substrate complexes by extending the C-terminus of NS6 construct to include residues on the C-terminal (P′) side of the cleavage junction. We report the crystallization and crystal structure determination of inactive mutants of murine norovirus NS6 protease with C-terminal extensions of one, two and four residues from the N-terminus of the adjacent NS7 protein (NS6 1′, NS6 2′, NS6 4′). We also determined the structure of a chimeric extended NS6 protease in which the P4-P4′ sequence of the NS6-7 cleavage site was replaced with the corresponding sequence from the NS2-3 cleavage junction (NS6 4′ 2|3).The constructs NS6 1′ and NS6 2′ yielded crystals that diffracted anisotropically. We found that, although the uncorrected data could be phased by molecular replacement, refinement of the structures stalled unless the data were ellipsoidally truncated and corrected with anisotropic B-factors. These corrections significantly improved phasing by molecular replacement and subsequent refinement.The refined structures of all four extended NS6 proteases are very similar in structure to the mature MNV NS6—and in one case reveal additional details of a surface loop. Although the packing arrangement observed showed some similarities to those observed in the adventitious protease-product crystals reported previously, in no case were specific protease–substrate interactions observed. |
1,658 | Successful use of extracorporeal membrane oxygenation in a human immunodeficiency virus infected patient with severe acute respiratory distress syndrome | INTRODUCTION: We report a case of an adult patient with human immunodeficiency virus (HIV), acute respiratory distress syndrome (ARDS) and ventilator associated pneumonia (VAP) caused by multidrug resistant (MDR) bacteria that was successfully managed with veno-venous extracorporeal membrane oxygenation (ECMO). CASE REPORT: A 25 year old male with no significant past medical history had been admitted to a local hospital due to dyspnea and fever. His pulmonary function subsequently failed necessitating mechanical ventilation (MV) and introduction of ECMO support. The patient was transported for 300 km by road on ECMO to a tertiary medical center. The diagnosis of ARDS, HIV infection and MDR bacterial and fungal VAP was made. Patient was successfully treated with antiretroviral therapy (ART), anti-infective agents and 58 days of veno-venous ECMO support, with complete resolution of the respiratory symptoms. CONCLUSION: HIV infected patients with ARDS and MDR bacterial VAP whose HIV replication is controlled by ART could be successfully managed with ECMO. |
1,659 | Innovations in research ethics governance in humanitarian settings | BACKGROUND: Médecins Sans Frontières (MSF) is one of the world’s leading humanitarian medical organizations. The increased emphasis in MSF on research led to the creation of an ethics review board (ERB) in 2001. The ERB has encouraged innovation in the review of proposals and the interaction between the ERB and the organization. This has led to some of the advances in ethics governance described in this paper. DISCUSSION: We first update our previous work from 2009 describing ERB performance and then highlight five innovative practices: • A new framework to guide ethics review • The introduction of a policy exempting a posteriori analysis of routinely collected data • The preapproval of “emergency” protocols • General ethical approval of “routine surveys” • Evaluating the impact of approved studies The new framework encourages a conversation about ethical issues, rather than imposing quasi-legalistic rules, is more engaged with the specific MSF research context and gives greater prominence to certain values and principles. Some of the innovations implemented by the ERB, such as review exemption or approval of generic protocols, may run counter to many standard operating procedures. We argue that much standard practice in research ethics review ought to be open to challenge and revision. Continued interaction between MSF researchers and independent ERB members has allowed for progressive innovations based on a trustful and respectful partnership between the ERB and the researchers. In the future, three areas merit particular attention. First, the impact of the new framework should be assessed. Second, the impact of research needs to be defined more precisely as a first step towards being meaningfully assessed, including changes of impact over time. Finally, the dialogue between the MSF ERB and the ethics committees in the study countries should be enhanced. SUMMARY: We hope that the innovations in research ethics governance described may be relevant for other organisations carrying out research in fragile contexts and for ethics committees reviewing such research. |
1,660 | The Role of Misshapen NCK-related kinase (MINK), a Novel Ste20 Family Kinase, in the IRES-Mediated Protein Translation of Human Enterovirus 71 | Human Enterovirus 71 (EV71) commonly causes Hand, Foot and Mouth Disease in young children, and occasional occurrences of neurological complications can be fatal. In this study, a high-throughput cell-based screening on the serine/threonine kinase siRNA library was performed to identify potential antiviral agents against EV71 replication. Among the hits, Misshapen/NIKs-related kinase (MINK) was selected for detailed analysis due to its strong inhibitory profile and novelty. In the investigation of the stage at which MINK is involved in EV71 replication, virus RNA transfection in MINK siRNA-treated cells continued to cause virus inhibition despite bypassing the normal entry pathway, suggesting its involvement at the post-entry stage. We have also shown that viral RNA and protein expression level was significantly reduced upon MINK silencing, suggesting its involvement in viral protein synthesis which feeds into viral RNA replication process. Through proteomic analysis and infection inhibition assay, we found that the activation of MINK was triggered by early replication events, instead of the binding and entry of the virus. Proteomic analysis on the activation profile of p38 Mitogen-activated Protein Kinase (MAPK) indicated that the phosphorylation of p38 MAPK was stimulated by EV71 infection upon MINK activation. Luciferase reporter assay further revealed that the translation efficiency of the EV71 internal ribosomal entry site (IRES) was reduced after blocking the MINK/p38 MAPK pathway. Further investigation on the effect of MINK silencing on heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) localisation demonstrated that cytoplasmic relocalisation of hnRNP A1 upon EV71 infection may be facilitated via the MINK/p38 MAPK pathway which then positively regulates the translation of viral RNA transcripts. These novel findings hence suggest that MINK plays a functional role in the IRES-mediated translation of EV71 viral RNA and may provide a potential target for the development of specific antiviral strategies against EV71 infection. |
1,661 | Genetic diversity of the 2013–14 human isolates of influenza H7N9 in China | BACKGROUND: Influenza H7N9 has become an endemic pathogen in China where circulating virus is found extensively in wild birds and domestic poultry. Two epidemic waves of Human H7N9 infections have taken place in Eastern and South Central China during the years of 2013 and 2014. In this study, we report on the first four human cases of influenza H7N9 in Shantou, Guangdong province, which occurred during the second H7N9 wave, and the subsequent analysis of the viral isolates. METHODS: Viral genomes were subjected to multisegment amplification and sequenced in an Illumina MiSeq. Later, phylogenetic analyses of influenza H7N9 viruses were performed to establish the evolutionary context of the disease in humans. RESULTS: The sequences of the isolates from Shantou have closer evolutionary proximity to the predominant Eastern H7N9 cluster (similar to A/Shanghai/1/2013 (H7N9)) than to the Southern H7N9 cluster (similar to A/Guangdong/1/2013 (H7N9)). CONCLUSIONS: Two distinct phylogenetic groups of influenza H7N9 circulate currently in China and cause infections in humans as a consequence of cross-species spillover from the avian disease. The Eastern cluster, which includes the four isolates from Shantou, presents a wide geographic distribution and overlaps with the more restricted area of circulation of the Southern cluster. Continued monitoring of the avian disease is of critical importance to better understand and predict the epidemiological behaviour of the human cases. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12879-015-0829-8) contains supplementary material, which is available to authorized users. |
1,662 | Explaining and responding to the Ebola epidemic | The Ebola epidemic in West Africa is not merely a biomedical problem that can be seen in isolation and dealt with only through emergency medical rescue processes. The ethical dilemmas surfaced by this epidemic are also not confined to the usual micro-ethical problems associated with medical care and medical research. The pandemic, as one of many manifestations of failed human and social development that has brought the world to dangerous ‘tipping points’, requires deep introspection and action to address upstream causal processes. |
1,663 | Why language matters: insights and challenges in applying a social determination of health approach in a North-South collaborative research program | BACKGROUND: Focus on “social determinants of health” provides a welcome alternative to the bio-medical illness paradigm. However, the tendency to concentrate on the influence of “risk factors” related to living and working conditions of individuals, rather than to more broadly examine dynamics of the social processes that affect population health, has triggered critical reaction not only from the Global North but especially from voices the Global South where there is a long history of addressing questions of health equity. In this article, we elaborate on how focusing instead on the language of “social determination of health” has prompted us to attempt to apply a more equity-sensitive approaches to research and related policy and praxis. DISCUSSION: In this debate, we briefly explore the epistemological and historical roots of epidemiological approaches to health and health equity that have emerged in Latin America to consider its relevance to global discourse. In this region marked by pronounced inequity, context-sensitive concepts such as “collective health” and “critical epidemiology” have been prominent, albeit with limited acknowledgement by the Global North. We illustrate our attempts to apply a social determination approach (and the “4 S” elements of bio-Security, Sovereignty, Solidarity and Sustainability) in five projects within our research collaboration linking researchers and knowledge users in Ecuador and Canada, in diverse settings (health of healthcare workers; food systems; antibiotic resistance; vector borne disease [dengue]; and social circus with street youth). CONCLUSIONS: We argue that the language of social determinants lends itself to research that is more reductionist and beckons the development of different skills than would be applied when adopting the language of social determination. We conclude that this language leads to more direct analysis of the systemic factors that drive, promote and reinforce disparities, while at the same time directly considering the emancipatory forces capable of countering negative health impacts. It follows that “reverse innovation” must not only recognize practical solutions being developed in low and middle income countries, but must also build on the strengths of the theoretical-methodological reasoning that has emerged in the South. |
1,664 | Prevalence and Correlation of Infectious Agents in Hospitalized Children with Acute Respiratory Tract Infections in Central China | Acute respiratory tract infections (ARTIs) are associated with significant morbidity and mortality worldwide, especially in children under the age of 5 years. Almost 2 million children die from ARTIs each year, and most of them are from developing countries. The prevalence and correlation of pathogens in ARTIs are poorly understood, but are critical for improving case prevention, treatment, and management. In this study, we investigated the prevalence and correlation of infectious agents in children with ARTIs. A total of 39,756 children with one or more symptoms, including fever, cough, sore throat, tonsillitis, pharyngitis, herpangina, pneumonia, and bronchiolitis, were enrolled in the study. All patients were hospitalized in Wuhan Children’s Hospital between October 1, 2010 and September 30, 2012, and were evaluated for infectious agents. Pathogens, including Mycoplasma pneumoniae, influenza A virus, influenza B virus, adenoviruses, respiratory syncytial virus, parainfluenza virus, Legionella pneumophila, Chlamydophila pneumoniae, and Coxiella burnetii, were screened simultaneously in patient blood samples using anti-pathogen IgM tests. Regression analysis was used to reveal correlations among the pathogens. Our results showed that one or more pathogens were identified in 10,206 patients, and that Mycoplasma pneumoniae, adenoviruses, and influenza B virus were the leading infectious agents. Mixed-infections of pathogens were detected in 2,391 cases, with Mycoplasma pneumoniae as the most frequent pathogen. The most common agents in the co-infections were Mycoplasma pneumoniae and influenza B virus. Regression analysis revealed a linear correlation between the proportion of mixed infections and the incidence of multi-pathogen infections. The prevalence of infectious agents in children with ARTIs was determined. Equations were established to estimate multiple infections by single-pathogen detection. This revealed a linear correlation for pathogens in children with ARTIs. This study provides useful information for improving case prevention and management. |
1,665 | A Micropolymorphism Altering the Residue Triad 97/114/156 Determines the Relative Levels of Tapasin Independence and Distinct Peptide Profiles for HLA-A(*)24 Allotypes | While many HLA class I molecules interact directly with the peptide loading complex (PLC) for conventional loading of peptides certain class I molecules are able to present peptides in a way that circumvents the PLC components. We investigated micropolymorphisms at position 156 of HLA-A(*)24 allotypes and their effects on PLC dependence for assembly and peptide binding specificities. HLA-A(*)24:06(156Trp) and HLA-A(*)24:13(156Leu) showed high levels of cell surface expression while HLA-A(*)24:02(156Gln) was expressed at low levels in tapasin deficient cells. Peptides presented by these allelic variants showed distinct differences in features and repertoire. Immunoprecipitation experiments demonstrated all the HLA-A(*)24/156 variants to associate at similar levels with tapasin when present. Structurally, HLA-A(*)24:02 contains the residue triad Met97/His114/Gln156 and a Trp156 or Leu156 polymorphism provides tapasin independence by stabilizing these triad residues, thus generating an energetically stable and a more peptide receptive environment. Micropolymorphisms at position 156 can influence the generic peptide loading pathway for HLA-A(*)24 by altering their tapasin dependence for peptide selection. The trade-off for this tapasin independence could be the presentation of unusual ligands by these alleles, imposing significant risk following hematopoietic stem cell transplantation (HSCT). |
1,666 | Setting healthcare priorities in hospitals: a review of empirical studies | Priority setting research has focused on the macro (national) and micro (bedside) level, leaving the meso (institutional, hospital) level relatively neglected. This is surprising given the key role that hospitals play in the delivery of healthcare services and the large proportion of health systems resources that they absorb. To explore the factors that impact upon priority setting at the hospital level, we conducted a thematic review of empirical studies. A systematic search of PubMed, EBSCOHOST, Econlit databases and Google scholar was supplemented by a search of key websites and a manual search of relevant papers’ reference lists. A total of 24 papers were identified from developed and developing countries. We applied a policy analysis framework to examine and synthesize the findings of the selected papers. Findings suggest that priority setting practice in hospitals was influenced by (1) contextual factors such as decision space, resource availability, financing arrangements, availability and use of information, organizational culture and leadership, (2) priority setting processes that depend on the type of priority setting activity, (3) content factors such as priority setting criteria and (4) actors, their interests and power relations. We observe that there is need for studies to examine these issues and the interplay between them in greater depth and propose a conceptual framework that might be useful in examining priority setting practices in hospitals. |
1,667 | Intranasal Administration of Maleic Anhydride-Modified Human Serum Albumin for Pre-Exposure Prophylaxis of Respiratory Syncytial Virus Infection | Respiratory syncytial virus (RSV) is the leading cause of pediatric viral respiratory tract infections. Neither vaccine nor effective antiviral therapy is available to prevent and treat RSV infection. Palivizumab, a humanized monoclonal antibody, is the only product approved to prevent serious RSV infection, but its high cost is prohibitive in low-income countries. Here, we aimed to identify an effective, safe, and affordable antiviral agent for pre-exposure prophylaxis (PrEP) of RSV infection in children at high risk. We found that maleic anhydride (ML)-modified human serum albumin (HSA), designated ML-HSA, exhibited potent antiviral activity against RSV and that the percentages of the modified lysines and arginies in ML- are correlated with such anti-RSV activity. ML-HSA inhibited RSV entry and replication by interacting with viral G protein and blocking RSV attachment to the target cells, while ML-HAS neither bound to F protein, nor inhibited F protein-mediated membrane fusion. Intranasal administration of ML-HSA before RSV infection resulted in significant decrease of the viral titers in the lungs of mice. ML-HSA shows promise for further development into an effective, safe, affordable, and easy-to-use intranasal regimen for pre-exposure prophylaxis of RSV infection in children at high risk in both low- and high-income countries. |
1,668 | Development of Monoclonal Antibodies in China: Overview and Prospects | Monoclonal antibodies (mAbs) have become increasingly important as human therapeutic agents. Yet, current research concentrates on technology itself and pays attention to developed countries. This paper aims to provide a comprehensive review of mAbs development in China through systematic analysis of drug registry, patent applications, clinical trials, academic publication, and ongoing R&D projects. The trends in therapeutic areas and industrialization process are also highlighted. Development and research trends of mAbs are analyzed to provide a future perspective of mAbs as therapeutic agents in China. |
1,669 | Proteome mapping of epidermal growth factor induced hepatocellular carcinomas identifies novel cell metabolism targets and mitogen activated protein kinase signalling events | BACKGROUND: Hepatocellular carcinoma (HCC) is on the rise and the sixth most common cancer worldwide. To combat HCC effectively research is directed towards its early detection and the development of targeted therapies. Given the fact that epidermal growth factor (EGF) is an important mitogen for hepatocytes we searched for disease regulated proteins to improve an understanding of the molecular pathogenesis of EGF induced HCC. Disease regulated proteins were studied by 2DE MALDI-TOF/TOF and a transcriptomic approach, by immunohistochemistry and advanced bioinformatics. RESULTS: Mapping of EGF induced liver cancer in a transgenic mouse model identified n = 96 (p < 0.05) significantly regulated proteins of which n = 54 were tumour-specific. To unravel molecular circuits linked to aberrant EGFR signalling diverse computational approaches were employed and this defined n = 7 key nodes using n = 82 disease regulated proteins for network construction. STRING analysis revealed protein-protein interactions of > 70% disease regulated proteins with individual proteins being validated by immunohistochemistry. The disease regulated network proteins were mapped to distinct pathways and bioinformatics provided novel insight into molecular circuits associated with significant changes in either glycolysis and gluconeogenesis, argine and proline metabolism, protein processing in endoplasmic reticulum, Hif- and MAPK signalling, lipoprotein metabolism, platelet activation and hemostatic control as a result of aberrant EGF signalling. The biological significance of the findings was corroborated with gene expression data derived from tumour tissues to evntually define a rationale by which tumours embark on intriguing changes in metabolism that is of utility for an understanding of tumour growth. Moreover, among the EGF tumour specific proteins n = 11 were likewise uniquely expressed in human HCC and for n = 49 proteins regulation in human HCC was confirmed using the publically available Human Protein Atlas depository, therefore demonstrating clinical significance. CONCLUSION: Novel insight into the molecular pathogenesis of EGF induced liver cancer was obtained and among the 37 newly identified proteins several are likely candidates for the development of molecularly targeted therapies and include the nucleoside diphosphate kinase A, bifunctional ATP-dependent dihydroyacetone kinase and phosphatidylethanolamine-binding protein1, the latter being an inhibitor of the Raf-1 kinase. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-015-1312-z) contains supplementary material, which is available to authorized users. |
1,670 | Neonatal Outcomes After Antenatal Influenza Immunization During the 2009 H1N1 Influenza Pandemic: Impact on Preterm Birth, Birth Weight, and Small for Gestational Age Birth | Background. Influenza infection during pregnancy is associated with adverse fetal outcomes such as preterm birth and small for gestational age (SGA). Maternal influenza immunization may prevent these adverse infant outcomes during periods of influenza circulation. Methods. We conducted a retrospective cohort study of live births within Kaiser Permanente (KP) Georgia and Mid-Atlantic States (n = 3327) during the period of 2009 influenza A (H1N1) virus circulation. Primary outcomes were third-trimester preterm birth (27–36 weeks), birth weight, low birth weight (LBW, <2500 g), and SGA. Results. There were 327 (9.8%) preterm, 236 (7.4%) LBW, and 267 (8.4%) SGA births. Among H1N1-vaccinated mothers (n = 1125), there were 86 (7.6%) preterm, 68 (6.4%) LBW, and 99 (9.3%) SGA births, and the mean birth weight was 3308.5 g (95% confidence interval [CI], 3276.6–3340.4). Among unvaccinated mothers (n = 1581), there were 191 (12.1%) preterm, 132 (8.8%) LBW, and 123 (8.2%) SGA births, and the mean birth weight was 3245.3 g (95% CI, 3216.5–3274.2). Infants of H1N1-vaccinated mothers had 37% lower odds of being born preterm than infants of unvaccinated mothers (adjusted odds ratio, 0.63 [95% CI, .47–.84]). The mean birth weight difference between infants of H1N1-vaccinated mothers and infants of unvaccinated mothers was 45.1 g (95% CI, 1.8–88.3). There was no significant association between maternal H1N1 influenza immunization and LBW or SGA. Conclusions. Pregnant women who received H1N1 influenza vaccine were less likely to give birth preterm, and gave birth to heavier infants. The findings support US vaccine policy choices to prioritize pregnant women during the 2009 influenza A (H1N1) pandemic. |
1,671 | Vimentin regulates activation of the NLRP3 inflammasome | Activation of the NLRP3 inflammasome and subsequent maturation of IL-1β have been implicated in acute lung injury (ALI), resulting in inflammation and fibrosis. We investigated the role of vimentin, a type III intermediate filament, in this process using three well-characterized murine models of ALI known to require NLRP3 inflammasome activation. We demonstrate that central pathophysiologic events in ALI (inflammation, IL-1β levels, endothelial and alveolar epithelial barrier permeability, remodelling and fibrosis) are attenuated in the lungs of Vim(−/−) mice challenged with LPS, bleomycin and asbestos. Bone marrow chimeric mice lacking vimentin have reduced IL-1β levels and attenuated lung injury and fibrosis following bleomycin exposure. Furthermore, decreased active caspase-1 and IL-1β levels are observed in vitro in Vim(−/−) and vimentin-knockdown macrophages. Importantly, we show direct protein–protein interaction between NLRP3 and vimentin. This study provides insights into lung inflammation and fibrosis and suggests that vimentin may be a key regulator of the NLRP3 inflammasome. SUPPLEMENTARY INFORMATION: The online version of this article (doi:10.1038/ncomms7574) contains supplementary material, which is available to authorized users. |
1,672 | Chest radiographic data acquisition and quality assurance in multicenter studies | Background. Multicenter studies rely on data derived from different institutions. Forms can be designed to standardize the reporting process allowing reliable comparison of data. Objective. The purpose of the report is to provide a standardized method, developed as a part of a multicenter study of vertically transmitted HIV, for assessing chest radiographic results. Materials and methods. Eight hundred and five infants and children were studied at five centers; 3057 chest radiographs were scored. Data were entered using a forced-choice, graded response for 12 findings. Quality assurance measures and inter-rater agreement statistics are reported. Results. The form used for reporting chest radiographic results is presented. Inter-rater agreement was moderate to high for most findings, with the best correlation reported for the presence of bronchovascular markings and/or reticular densities addressed as a composite question (kappa = 0.71). The presence of nodular densities (kappa = 0.56) and parenchymal consolidation (kappa = 0.57) had moderate agreement. Agreement for lung volume was low. Conclusion. The current tool, developed for use in the pediatric population, is applicable to any study involving the assessment of pediatric chest radiographs for a large population, whether at one or many centers. |
1,673 | Impact of Porcine Epidemic Diarrhea on Performance of Growing Pigs | The impact of porcine epidemic diarrhea virus (PEDv) infection on the US pork industry has mainly been attributed to the mortality that it causes in suckling piglets, and, consequently, much effort has been invested in the quantification of its effect in sow farms. However, no information on the performance of surviving pigs that were exposed to the PEDv as piglets is available. Here, a retrospective cohort study to evaluate the impact of porcine epidemic diarrhea virus (PEDv) infection on growing pigs’ performance, as indicated by mortality, average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) was performed using production records from weaned pigs in nursery and wean-to-finish sites from sow farms that became PEDv-infected between May 2013 and June 2014. Production records from the first batch of growing pigs weaned in infected flows after the PEDv outbreak (“infected batches”) were compared with those from pigs weaned within the previous 14 to 120 days (“control batches”). Performance records from infected and control batches, paired by flow, were compared using non-parametric paired tests. Mortality, ADG and FCR were significantly different in PEDv-positive (infected) compared with PEDv-negative (control) batches, with a mean increase of mortality and FCR of 11% and 0.5, respectively, and a decrease of ADG of 0.16 lb/day. Our results demonstrate a poorer performance of growing pigs weaned after a PEDv outbreak compared with those weaned within the previous 14-120 days, suggesting that in addition to the mortality induced by PEDv in suckling pigs, the disease also impairs the performance of surviving pig. These findings help to quantify the impact of PEDv infection in the US and, ultimately, contribute to efforts to quantify the cost-effectiveness of disease prevention and control measures. |
1,674 | Hematopoietic Cancer Cell Lines Can Support Replication of Sabin Poliovirus Type 1 | Viral vaccines can be produced in adherent or in suspension cells. The objective of this work was to screen human suspension cell lines for the capacity to support viral replication. As the first step, it was investigated whether poliovirus can replicate in such cell lines. Sabin poliovirus type 1 was serially passaged on five human cell lines, HL60, K562, KG1, THP-1, and U937. Sabin type 1 was capable of efficiently replicating in three cell lines (K562, KG1, and U937), yielding high viral titers after replication. Expression of CD155, the poliovirus receptor, did not explain susceptibility to replication, since all cell lines expressed CD155. Furthermore, we showed that passaged virus replicated more efficiently than parental virus in KG1 cells, yielding higher virus titers in the supernatant early after infection. Infection of cell lines at an MOI of 0.01 resulted in high viral titers in the supernatant at day 4. Infection of K562 with passaged Sabin type 1 in a bioreactor system yielded high viral titers in the supernatant. Altogether, these data suggest that K562, KG1, and U937 cell lines are useful for propagation of poliovirus. |
1,675 | Introduction of a point mutation into an HLA class I single-chain trimer induces enhancement of CTL priming and antitumor immunity | We previously discovered one particular HLA-A*02:01 mutant that enhanced peptide-specific cytotoxic T lymphocyte (CTL) recognition in vitro compared to wild-type HLA-A*02:01. This mutant contains a single amino acid substitution from histidine to leucine at position 74 (H74L) that is located in the peptide-binding groove. To investigate the effect of the H74L mutation on the in vivo CTL priming, we took advantage of the technology of the HLA class I single-chain trimer (SCT) in which three components involving a peptide, β2 microglobulin and the HLA class I heavy chain are joined together via flexible linkers. We generated recombinant adenovirus expressing SCT comprised influenza A matrix protein (FMP)-derived peptide, β2 microglobulin and the H74L heavy chain. HLA-A*02:01 transgenic mice were immunized with the adenovirus, and the induction of peptide-specific CTLs and antitumor immunity was investigated. It was clearly shown that the H74L mutation enabled the HLA-A*02:01 SCT molecule to dramatically enhance both in vivo priming of FMP-specific CTLs and protection against a lethal challenge of tumor cells expressing FMP. These data present the first evidence that a simple point mutation in the HLA class I heavy chain of SCT is beneficial for improving CTL-based immunotherapy and prophylaxis to control tumors. |
1,676 | Preparing for Ebola Virus Disease in West African countries not yet affected: perspectives from Ghanaian health professionals | BACKGROUND: The current Ebola Virus Disease (EVD) epidemic has ravaged the social fabric of three West African countries and affected people worldwide. We report key themes from an agenda-setting, multi-disciplinary roundtable convened to examine experiences and implications for health systems in Ghana, a nation without cases but where risk for spread is high and the economic, social and political impact of the impending threat is already felt. DISCUSSION: Participants’ personal stories and the broader debates to define fundamental issues and opportunities for preparedness focused on three inter-related themes. First, the dangers of the fear response itself were highlighted as a threat to the integrity and continuity of quality care. Second, healthcare workers’ fears were compounded by a demonstrable lack of societal and personal protections for infection prevention and control in communities and healthcare facilities, as evidenced by an ongoing cholera epidemic affecting over 20,000 patients in the capital Accra alone since June 2014. Third, a lack of coherent messaging and direction from leadership seems to have limited coordination and reinforced a level of mistrust in the government’s ability and commitment to mobilize an adequate response. Initial recommendations include urgent investment in the needed supplies and infrastructure for basic, routine infection control in communities and healthcare facilities, provision of assurances with securities for frontline healthcare workers, establishment of a multi-sector, “all-hazards” outbreak surveillance system, and engaging directly with key community groups to co-produce contextually relevant educational messages that will help decrease stigma, fear, and the demoralizing perception that the disease defies remedy or control. SUMMARY: The EVD epidemic provides an unprecedented opportunity for West African countries not yet affected by EVD cases to make progress on tackling long-standing health systems weaknesses. This roundtable discussion emphasized the urgent need to strengthen capacity for infection control, occupational health and safety, and leadership coordination. Significant commitment is needed to raise standards of hygiene in communities and health facilities, build mechanisms for collaboration across sectors, and engage community stakeholders in creating the needed solutions. It would be both devastating and irresponsible to waste the opportunity. |
1,677 | The Relationship of CSF and Plasma Cytokine Levels in HIV Infected Patients with Neurocognitive Impairment | Although HAD is now rare due to HAART, the milder forms of HAND persist in HIV-infected patients. HIV-induced systemic and localized inflammation is considered to be one of the mechanisms of HAND. The levels of cytokines in CSF were associated with neurocognitive impairment in HIV infection. However, the changes of cytokines involved in cognition impairment in plasma have not been shown, and their relationships between CSF and plasma require to be addressed. We compared cytokine levels in paired CSF and plasma samples from HIV-infected individuals with or without neurocognitive impairment. Cytokine concentrations were measured by Luminex xMAP. In comparing the expression levels of cytokines in plasma and CSF, IFN-α2, IL-8, IP-10, and MCP-1 were significantly higher in CSF. Eotaxin was significantly higher in plasma, whereas G-CSF showed no difference between plasma and CSF. G-CSF (P = 0.0079), IL-8 (P = 0.0223), IP-10 (P = 0.0109), and MCP-1 (P = 0.0497) in CSF showed significant difference between HIV-CI and HIV-NC group, which may indicate their relationship to HIV associated neurocognitive impairment. In addition, G-CSF (P = 0.0191) and IP-10 (P = 0.0377) in plasma were significantly higher in HIV-CI than HIV-NC. The consistent changes of G-CSF and IP-10 in paired plasma and CSF samples might enhance their potential for predicting HAND. |
1,678 | Vaccination with Human Papillomavirus Pseudovirus-Encapsidated Plasmids Targeted to Skin Using Microneedles | Human papilloma virus-like particles (HPV VLP) serve as the basis of the current licensed vaccines for HPV. We have previously shown that encapsidation of DNA expressing the model antigen M/M2 from respiratory syncytial virus (RSV) in HPV pseudovirions (PsV) is immunogenic when delivered intravaginally. Because the HPV capsids confer tropism for basal epithelium, they represent attractive carriers for vaccination targeted to the skin using microneedles. In this study we asked: 1) whether HPV16 VLP administered by microneedles could induce protective immune responses to HPV16 and 2) whether HPV16 PsV-encapsidated plasmids delivered by microneedles could elicit immune responses to both HPV and the antigen delivered by the transgene. Mice immunized with HPV16 VLP coated microneedles generated robust neutralizing antibody responses and were protected from HPV16 challenge. Microneedle arrays coated with HPV16-M/M2 or HPV16-F protein (genes of RSV) were then tested and dose-dependent HPV and F-specific antibody responses were detected post-immunization, and M/M2-specific T-cell responses were detected post RSV challenge, respectively. HPV16 PsV-F immunized mice were fully protected from challenge with HPV16 PsV and had reduced RSV viral load in lung and nose upon intranasal RSV challenge. In summary, HPV16 PsV-encapsidated DNA delivered by microneedles induced neutralizing antibody responses against HPV and primed for antibody and T-cell responses to RSV antigens encoded by the encapsidated plasmids. Although the immunogenicity of the DNA component was just above the dose response threshold, the HPV-specific immunity was robust. Taken together, these data suggest microneedle delivery of lyophilized HPV PsV could provide a practical, thermostable combined vaccine approach that could be developed for clinical evaluation. |
1,679 | A Novel Host-Proteome Signature for Distinguishing between Acute Bacterial and Viral Infections | Bacterial and viral infections are often clinically indistinguishable, leading to inappropriate patient management and antibiotic misuse. Bacterial-induced host proteins such as procalcitonin, C-reactive protein (CRP), and Interleukin-6, are routinely used to support diagnosis of infection. However, their performance is negatively affected by inter-patient variability, including time from symptom onset, clinical syndrome, and pathogens. Our aim was to identify novel viral-induced host proteins that can complement bacterial-induced proteins to increase diagnostic accuracy. Initially, we conducted a bioinformatic screen to identify putative circulating host immune response proteins. The resulting 600 candidates were then quantitatively screened for diagnostic potential using blood samples from 1002 prospectively recruited patients with suspected acute infectious disease and controls with no apparent infection. For each patient, three independent physicians assigned a diagnosis based on comprehensive clinical and laboratory investigation including PCR for 21 pathogens yielding 319 bacterial, 334 viral, 112 control and 98 indeterminate diagnoses; 139 patients were excluded based on predetermined criteria. The best performing host-protein was TNF-related apoptosis-inducing ligand (TRAIL) (area under the curve [AUC] of 0.89; 95% confidence interval [CI], 0.86 to 0.91), which was consistently up-regulated in viral infected patients. We further developed a multi-protein signature using logistic-regression on half of the patients and validated it on the remaining half. The signature with the highest precision included both viral- and bacterial-induced proteins: TRAIL, Interferon gamma-induced protein-10, and CRP (AUC of 0.94; 95% CI, 0.92 to 0.96). The signature was superior to any of the individual proteins (P<0.001), as well as routinely used clinical parameters and their combinations (P<0.001). It remained robust across different physiological systems, times from symptom onset, and pathogens (AUCs 0.87-1.0). The accurate differential diagnosis provided by this novel combination of viral- and bacterial-induced proteins has the potential to improve management of patients with acute infections and reduce antibiotic misuse. |
1,680 | Personal genomes, quantitative dynamic omics and personalized medicine | The rapid technological developments following the Human Genome Project have made possible the availability of personalized genomes. As the focus now shifts from characterizing genomes to making personalized disease associations, in combination with the availability of other omics technologies, the next big push will be not only to obtain a personalized genome, but to quantitatively follow other omics. This will include transcriptomes, proteomes, metabolomes, antibodyomes, and new emerging technologies, enabling the profiling of thousands of molecular components in individuals. Furthermore, omics profiling performed longitudinally can probe the temporal patterns associated with both molecular changes and associated physiological health and disease states. Such data necessitates the development of computational methodology to not only handle and descriptively assess such data, but also construct quantitative biological models. Here we describe the availability of personal genomes and developing omics technologies that can be brought together for personalized implementations and how these novel integrated approaches may effectively provide a precise personalized medicine that focuses on not only characterization and treatment but ultimately the prevention of disease. |
1,681 | Merging Economics and Epidemiology to Improve the Prediction and Management of Infectious Disease | Mathematical epidemiology, one of the oldest and richest areas in mathematical biology, has significantly enhanced our understanding of how pathogens emerge, evolve, and spread. Classical epidemiological models, the standard for predicting and managing the spread of infectious disease, assume that contacts between susceptible and infectious individuals depend on their relative frequency in the population. The behavioral factors that underpin contact rates are not generally addressed. There is, however, an emerging a class of models that addresses the feedbacks between infectious disease dynamics and the behavioral decisions driving host contact. Referred to as “economic epidemiology” or “epidemiological economics,” the approach explores the determinants of decisions about the number and type of contacts made by individuals, using insights and methods from economics. We show how the approach has the potential both to improve predictions of the course of infectious disease, and to support development of novel approaches to infectious disease management. |
1,682 | Proteomic Analysis of Urine Exosomes Reveals Renal Tubule Response to Leptospiral Colonization in Experimentally Infected Rats | BACKGROUND: Infectious Leptospira colonize the kidneys of reservoir (e.g. rats) and accidental hosts such as humans. The renal response to persistent leptospiral colonization, as measured by urinary protein biosignatures, has not been systematically studied. Urinary exosomes--bioactive membrane-bound nanovesicles--contain cell-state specific cargo that additively reflect formation all along the nephron. We hypothesized that Leptospira-infection will alter the content of urine exosomes, and further, that these Leptospira-induced alterations will hold clues to unravel novel pathways related to bacterial-host interactions. METHODOLOGY/PRINCIPAL FINDINGS: Exosome protein content from 24 hour urine samples of Leptospira-infected rats was compared with that of uninfected rats using SDS-PAGE and liquid chromatography/tandem mass spectrometry (LC-MS/MS). Statistical models were used to identify significantly dysregulated proteins in Leptospira-infected and uninfected rat urine exosomes. In all, 842 proteins were identified by LC-MS/MS proteomics of total rat urine and 204 proteins associated specifically with exosomes. Multivariate analysis showed that 25 proteins significantly discriminated between uninfected control and infected rats. Alanyl (membrane) aminopeptidase, also known as CD13 topped this list with the highest score, a finding we validated by Western immunoblotting. Whole urine analysis showed Tamm-Horsfall protein level reduction in the infected rat urine. Total urine and exosome proteins were significantly different in male vs. female infected rats. CONCLUSIONS: We identified exosome-associated renal tubule-specific responses to Leptospira infection in a rat chronic colonization model. Quantitative differences in infected male and female rat urine exosome proteins vs. uninfected controls suggest that urine exosome analysis identifies important differences in kidney function that may be of clinical and pathological significance. |
1,683 | Using the Pathogenic and Nonpathogenic Nonhuman Primate Model for Studying Non-AIDS Comorbidities | With the advent of antiretroviral therapy that can control virus replication below the detection levels of conventional assays, a new clinical landscape of AIDS emerged, in which non-AIDS complications prevail over AIDS-defining conditions. These comorbidities are diverse and affect multiple organs, thus resulting in cardiovascular, kidney, neurocognitive and liver disease, osteopenia/osteoporosis, and cancers. A common feature of these conditions is that they are generally associated with accelerated aging. The mechanism behind these comorbidities is chronic excessive inflammation induced by HIV infection, which persists under antiretroviral therapy. Progressive simian immunodeficiency virus (SIV) infection of nonhuman primates (NHPs) closely reproduces these comorbidities and offers a simplified system in which most of the traditional human risk factors for comorbidities (i.e., smoking, hyperlipidemia) are absent. Additionally, experimental conditions can be properly controlled during a shorter course of disease for SIV infection. As such, NHPs can be employed to characterize new paradigms of AIDS pathogenesis and to test the efficacy of interventions aimed at alleviating non-AIDS-related comorbidities. |
1,684 | The combination of decoy receptor 3 and soluble triggering receptor expressed on myeloid cells-1 for the diagnosis of nosocomial bacterial meningitis | BACKGROUND: Early diagnosis and appropriate antibiotic treatment can significantly reduce mortality of nosocomial bacterial meningitis. However, it is a challenge for clinicians to make an accurate and rapid diagnosis of bacterial meningitis. This study aimed at determining whether combined biomarkers can provide a useful tool for the diagnosis of bacterial meningitis. METHODS: A retrospective study was carried out. Cerebrospinal fluid (CSF) levels of decoy receptor 3 (DcR3) and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: The patients with bacterial meningitis had significantly elevated levels of the above mentioned biomarkers. The two biomarkers were all risk factors with bacterial meningitis. The biomarkers were constructed into a “bioscore”. The discriminative performance of the bioscore was better than that of each biomarker, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.842 (95% confidence intervals (CI) 0.770–0.914; p< 0.001). CONCLUSIONS: Combined measurement of CSF DcR3 and sTREM-1 concentrations improved the prediction of nosocomial bacterial meningitis. The combined strategy is of interest and the validation of that improvement needs further studies. |
1,685 | Gaining Insights into the Codon Usage Patterns of TP53 Gene across Eight Mammalian Species | TP53 gene is known as the “guardian of the genome” as it plays a vital role in regulating cell cycle, cell proliferation, DNA damage repair, initiation of programmed cell death and suppressing tumor growth. Non uniform usage of synonymous codons for a specific amino acid during translation of protein known as codon usage bias (CUB) is a unique property of the genome and shows species specific deviation. Analysis of codon usage bias with compositional dynamics of coding sequences has contributed to the better understanding of the molecular mechanism and the evolution of a particular gene. In this study, the complete nucleotide coding sequences of TP53 gene from eight different mammalian species were used for CUB analysis. Our results showed that the codon usage patterns in TP53 gene across different mammalian species has been influenced by GC bias particularly GC(3) and a moderate bias exists in the codon usage of TP53 gene. Moreover, we observed that nature has highly favored the most over represented codon CTG for leucine amino acid but selected against the ATA codon for isoleucine in TP53 gene across all mammalian species during the course of evolution. |
1,686 | The Highly Conserved Codon following the Slippery Sequence Supports −1 Frameshift Efficiency at the HIV-1 Frameshift Site | HIV-1 utilises −1 programmed ribosomal frameshifting to translate structural and enzymatic domains in a defined proportion required for replication. A slippery sequence, U UUU UUA, and a stem-loop are well-defined RNA features modulating −1 frameshifting in HIV-1. The GGG glycine codon immediately following the slippery sequence (the ‘intercodon’) contributes structurally to the start of the stem-loop but has no defined role in current models of the frameshift mechanism, as slippage is inferred to occur before the intercodon has reached the ribosomal decoding site. This GGG codon is highly conserved in natural isolates of HIV. When the natural intercodon was replaced with a stop codon two different decoding molecules—eRF1 protein or a cognate suppressor tRNA—were able to access and decode the intercodon prior to −1 frameshifting. This implies significant slippage occurs when the intercodon is in the (perhaps distorted) ribosomal A site. We accommodate the influence of the intercodon in a model of frame maintenance versus frameshifting in HIV-1. |
1,687 | Transcriptional regulation of secretory capacity by bZip transcription factors | Cells of specialized secretory organs expand their secretory pathways to accommodate the increased protein load necessary for their function. The endoplasmic reticulum (ER), the Golgi apparatus and the secretory vesicles, expand not only the membrane components but also the protein machinery required for increased protein production and transport. Increased protein load causes an ER stress response akin to the Unfolded Protein Response (UPR). Recent work has implicated several bZip transcription factors in the regulation of protein components of the early secretory pathway necessary to alleviate this stress. Here, we highlight eight bZip transcription factors in regulating secretory pathway component genes. These include components of the three canonical branches of the UPR-ATF4, XBP1, and ATF6, as well as the five members of the Creb3 family of transcription factors.We review findings from both invertebrate and vertebrate model systems suggesting that all of these proteins increase secretory capacity in response to increased protein load. Finally, we propose that the Creb3 family of factors may have a dual role in secretory cell differentiation by also regulating the pathways necessary for cell cycle exit during terminal differentiation. ELECTRONIC SUPPLEMENTARY MATERIAL: Supplementary material is available for this article at 10.1007/s11515-014-1338-7 and is accessible for authorized users. |
1,688 | Cleavage of Dicer Protein by I7 Protease during Vaccinia Virus Infection | Dicer is the key component in the miRNA pathway. Degradation of Dicer protein is facilitated during vaccinia virus (VV) infection. A C-terminal cleaved product of Dicer protein was detected in the presence of MG132 during VV infection. Thus, it is possible that Dicer protein is cleaved by a viral protease followed by proteasome degradation of the cleaved product. There is a potential I7 protease cleavage site in the C-terminus of Dicer protein. Indeed, reduction of Dicer protein was detected when Dicer was co-expressed with I7 protease but not with an I7 protease mutant protein lack of the protease activity. Mutation of the potential I7 cleavage site in the C-terminus of Dicer protein resisted its degradation during VV infection. Furthermore, Dicer protein was reduced dramatically by recombinant VV vI7Li after the induction of I7 protease. If VV could facilitate the degradation of Dicer protein, the process of miRNA should be affected by VV infection. Indeed, accumulation of precursor miR122 was detected after VV infection or I7 protease expression. Reduction of miR122 would result in the suppression of HCV sub-genomic RNA replication, and, in turn, the amount of viral proteins. As expected, significant reduction of HCVNS5A protein was detected after VV infection and I7 protease expression. Therefore, our results suggest that VV could cleave Dicer protein through I7 protease to facilitate Dicer degradation, and in turn, suppress the processing of miRNAs. Effect of Dicer protein on VV replication was also studied. Exogenous expression of Dicer protein suppresses VV replication slightly while knockdown of Dicer protein does not affect VV replication significantly. |
1,689 | Candidate New Rotavirus Species in Sheltered Dogs, Hungary | We identified unusual rotavirus strains in fecal specimens from sheltered dogs in Hungary by viral metagenomics. The novel rotavirus species displayed limited genome sequence homology to representatives of the 8 rotavirus species, A–H, and qualifies as a candidate new rotavirus species that we tentatively named Rotavirus I. |
1,690 | Advanced Molecular Surveillance of Hepatitis C Virus | Hepatitis C virus (HCV) infection is an important public health problem worldwide. HCV exploits complex molecular mechanisms, which result in a high degree of intrahost genetic heterogeneity. This high degree of variability represents a challenge for the accurate establishment of genetic relatedness between cases and complicates the identification of sources of infection. Tracking HCV infections is crucial for the elucidation of routes of transmission in a variety of settings. Therefore, implementation of HCV advanced molecular surveillance (AMS) is essential for disease control. Accounting for virulence is also important for HCV AMS and both viral and host factors contribute to the disease outcome. Therefore, HCV AMS requires the incorporation of host factors as an integral component of the algorithms used to monitor disease occurrence. Importantly, implementation of comprehensive global databases and data mining are also needed for the proper study of the mechanisms responsible for HCV transmission. Here, we review molecular aspects associated with HCV transmission, as well as the most recent technological advances used for virus and host characterization. Additionally, the cornerstone discoveries that have defined the pathway for viral characterization are presented and the importance of implementing advanced HCV molecular surveillance is highlighted. |
1,691 | Both ERK1 and ERK2 Are Required for Enterovirus 71 (EV71) Efficient Replication | It has been demonstrated that MEK1, one of the two MEK isoforms in Raf-MEK-ERK1/2 pathway, is essential for successful EV71 propagation. However, the distinct function of ERK1 and ERK2 isoforms, the downstream kinases of MEKs, remains unclear in EV71 replication. In this study, specific ERK siRNAs and selective inhibitor U0126 were applied. Silencing specific ERK did not significantly impact on the EV71-caused biphasic activation of the other ERK isoform, suggesting the EV71-induced activations of ERK1 and ERK2 were non-discriminative and independent to one another. Knockdown of either ERK1 or ERK2 markedly impaired progeny EV71 propagation (both by more than 90%), progeny viral RNA amplification (either by about 30% to 40%) and protein synthesis (both by around 70%), indicating both ERK1 and ERK2 were critical and not interchangeable to EV71 propagation. Moreover, suppression of EV71 replication by inhibiting both early and late phases of ERK1/2 activation showed no significant difference from that of only blocking the late phase, supporting the late phase activation was more importantly responsible for EV71 life cycle. Taken together, this study for the first time identified both ERK1 and ERK2 were required for EV71 efficient replication and further verified the important role of MEK1-ERK1/2 in EV71 replication. |
1,692 | Molecular characterization and phylogenetic analysis of transmissible gastroenteritis virus HX strain isolated from China | BACKGROUND: Porcine transmissible gastroenteritis virus (TGEV) is the major etiological agent of viral enteritis and severe diarrhea in suckling piglets. In China, TGEV has caused great economic losses, but its role in epidemic diarrhea is unclear. This study aims to reveal the etiological role of TGEV in piglet diarrhea via molecular characterization and phylogenetic analysis. RESULTS: A TGEV-HX strain was isolated from China, and its complete genome was amplified, cloned, and sequenced. Sequence analysis indicated that it was conserved in the 5′ and 3′-non-translated regions, and there were no insertions or deletions in nonstructural genes, such as ORF1a, ORF1b, ORF3a, ORF3b, and ORF7, as well as in genes encoding structural proteins, such as the envelope (E), membrane (M), and nucleoprotein (N) proteins. Furthermore, the phylogenetic analysis indicated that the TGEV-HX strain was more similar to the TGEV Purdue cluster than to the Miller cluster. CONCLUSIONS: The present study described the isolation and genetic characterization of a TGEV-HX strain. The detailed analysis of the genetic variation of TGEVs in China provides essential information for further understanding the evolution of TGEVs. |
1,693 | The Placental Protein Syncytin-1 Impairs Antiviral Responses and Exaggerates Inflammatory Responses to Influenza | BACKGROUND: Pregnancy increases susceptibility to influenza. The placenta releases an immunosuppressive endogenous retroviral protein syncytin-1. We hypothesised that exposure of peripheral monocytes (PBMCs) to syncytin-1 would impair responses to H1N1pdm09 influenza. METHODS AND FINDINGS: Recombinant syncytin-1 was produced. PBMCs from non-pregnant women (n=10) were exposed to H1N1pdm09 in the presence and absence of syncytin-1 and compared to responses of PBMCs from pregnant women (n=12). PBMCs were characterised using flow cytometry, release of interferon (IFN)-α, IFN-λ, IFN-γ, IL-10, IL-2, IL-6 and IL-1β were measured by cytometric bead array or ELISA. Exposure of PBMCs to H1N1pdm09 resulted in the release of IFN-α, (14,787 pg/mL, 95% CI 7311-22,264 pg/mL) IFN-λ (1486 pg/mL, 95% CI 756-2216 pg/mL) and IFN-γ (852 pg/mL, 95% CI 193-1511 pg/mL) after 48 hours. This was significantly impaired in pregnant women (IFN-α; p<0.0001 and IFN-λ; p<0.001). Furthermore, in the presence of syncytin-1, PBMCs demonstrated marked reductions in IFN-α and IFN-λ, while enhanced release of IL-10 as well as IL-6 and IL-1β. CONCLUSIONS: Our data indicates that a placental derived protein, syncytin-1 may be responsible for the heightened vulnerability of pregnant women to influenza. |
1,694 | Type I Interferon Response Is Delayed in Human Astrovirus Infections | Type I interferon (IFN) activation and its subsequent effects are important in the response to viral infections. Here we show that human astroviruses (HAstVs), which are important agents of acute gastroenteritis in children, induce a mild and delayed IFN response upon infecting CaCo-2 cells. Although IFN-β mRNA is detected within infected cells and supernatant from infected cells show antiviral activity against the replication of other well-known IFN-sensitive viruses, these responses occur at late stages of infection once genome replication has taken place. On the other hand, HAstV replication can be partially reduced by the addition of exogenous IFN, and inhibition of IFN activation by BX795 enhances viral replication, indicating that HAstVs are IFN-sensitive viruses. Finally, different levels of IFN response were observed in cells infected with different HAstV mutants with changes in the hypervariable region of nsP1a/4, suggesting that nsP1a/4 genotype may potentially have clinical implications due to its correlation with the viral replication phenotype and the antiviral responses induced within infected cells. |
1,695 | Sensitivity and Specificity of a Novel Classifier for the Early Diagnosis of Dengue | BACKGROUND: Dengue is the commonest arboviral disease of humans. An early and accurate diagnosis of dengue can support clinical management, surveillance and disease control and is central to achieving the World Health Organisation target of a 50% reduction in dengue case mortality by 2020. METHODS: 5729 children with fever of <72hrs duration were enrolled into this multicenter prospective study in southern Vietnam between 2010-2012. A composite of gold standard diagnostic tests identified 1692 dengue cases. Using statistical methods, a novel Early Dengue Classifier (EDC) was developed that used patient age, white blood cell count and platelet count to discriminate dengue cases from non-dengue cases. RESULTS: The EDC had a sensitivity of 74.8% (95%CI: 73.0-76.8%) and specificity of 76.3% (95%CI: 75.2-77.6%) for the diagnosis of dengue. As an adjunctive test alongside NS1 rapid testing, sensitivity of the composite test was 91.6% (95%CI: 90.4-92.9%). CONCLUSIONS: We demonstrate that the early diagnosis of dengue can be enhanced beyond the current standard of care using a simple evidence-based algorithm. The results should support patient management and clinical trials of specific therapies. |
1,696 | Transcriptional Regulation of Chemokine Expression in Ovarian Cancer | The increased expression of pro-inflammatory and pro-angiogenic chemokines contributes to ovarian cancer progression through the induction of tumor cell proliferation, survival, angiogenesis, and metastasis. The substantial potential of these chemokines to facilitate the progression and metastasis of ovarian cancer underscores the need for their stringent transcriptional regulation. In this Review, we highlight the key mechanisms that regulate the transcription of pro-inflammatory chemokines in ovarian cancer cells, and that have important roles in controlling ovarian cancer progression. We further discuss the potential mechanisms underlying the increased chemokine expression in drug resistance, along with our perspective for future studies. |
1,697 | In silico modification of oseltamivir as neuraminidase inhibitor of influenza A virus subtype H1N1 | This research focused on the modification of the functional groups of oseltamivir as neuraminidase inhibitor against influenza A virus subtype H1N1. Interactions of three of the best ligands were evaluated in the hydrated state using molecular dynamics simulation at two different temperatures. The docking result showed that AD3BF2D ligand (N-[(1S,6R)-5-amino-5-{[(2R,3S,4S)-3,4-dihydroxy-4-(hydroxymethyl) tetrahydrofuran-2-yl]oxy}-4-formylcyclohex-3-en-1-yl]acetamide-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate) had better binding energy values than standard oseltamivir. AD3BF2D had several interactions, including hydrogen bonds, with the residues in the catalytic site of neuraminidase as identified by molecular dynamics simulation. The results showed that AD3BF2D ligand can be used as a good candidate for neuraminidase inhibitor to cope with influenza A virus subtype H1N1. |
1,698 | Analysis of Chemokines and Receptors Expression Profile in the Myelin Mutant Taiep Rat | Taiep rat has a failure in myelination and remyelination processes leading to a state of hypomyelination throughout its life. Chemokines, which are known to play a role in inflammation, are also involved in the remyelination process. We aimed to demonstrate that remyelination-stimulating factors are altered in the brainstem of 1- and 6-month-old taiep rats. We used a Rat RT(2) Profiler PCR Array to assess mRNA expression of 84 genes coding for cytokines, chemokines, and their receptors. We also evaluated protein levels of CCL2, CCR1, CCR2, CCL5, CCR5, CCR8, CXCL1, CXCR2, CXCR4, FGF2, and VEGFA by ELISA. Sprague-Dawley rats were used as a control. PCR Array procedure showed that proinflammatory cytokines were not upregulated in the taiep rat. In contrast, some mRNA levels of beta and alpha chemokines were upregulated in 1-month-old rats, but CXCR4 was downregulated at their 6 months of age. ELISA results showed that CXCL1, CCL2, CCR2, CCR5, CCR8, and CXCR4 protein levels were decreased in brainstem at the age of 6 months. These results suggest the presence of a chronic neuroinflammation process with deficiency of remyelination-stimulating factors (CXCL1, CXCR2, and CXCR4), which might account for the demyelination in the taiep rat. |
1,699 | Heterologous Prime-Boost Regimens with a Recombinant Chimpanzee Adenoviral Vector and Adjuvanted F4 Protein Elicit Polyfunctional HIV-1-Specific T-Cell Responses in Macaques | HIV-1-specific CD4(+) and CD8(+) T lymphocytes are important for HIV-1 replication control. F4/AS01 consists of F4 recombinant fusion protein (containing clade B Gag/p24, Pol/RT, Nef and Gag/p17) formulated in AS01 Adjuvant System, and was shown to induce F4-specific polyfunctional CD4(+) T-cell responses in humans. While replication-incompetent recombinant HIV-1/SIV antigen-expressing human adenoviral vectors can elicit high-frequency antigen-specific CD8(+) T-cell responses, their use is hampered by widespread pre-existing immunity to human serotypes. Non-human adenovirus serotypes associated with lower prevalence may offer an alternative strategy. We evaluated the immunogenicity of AdC7-GRN (‘A’), a recombinant chimpanzee adenovirus type 7 vector expressing clade B Gag, RT and Nef, and F4/AS01 (‘P’), when delivered intramuscularly in homologous (PP or AA) and heterologous (AAPP or PPAA) prime-boost regimens, in macaques and mice. Vaccine-induced HIV-1-antigen-specific T cells in peripheral blood (macaques), liver, spleen, and intestinal and genital mucosa (mice) were characterized by intracellular cytokine staining. Vaccine-specific IgG antibodies (macaques) were detected using ELISA. In macaques, only the heterologous prime-boost regimens induced polyfunctional, persistent and balanced CD4(+) and CD8(+) T-cell responses specific to each HIV-1 vaccine antigen. AdC7-GRN priming increased the polyfunctionality of F4/AS01-induced CD4(+) T cells. Approximately 50% of AdC7-GRN-induced memory CD8(+) T cells exhibited an effector-memory phenotype. HIV-1-specific antibodies were detected with each regimen. In mice, antigen-specific CD4(+) and CD8(+) T-cell responses were detected in the mucosal and systemic anatomical compartments assessed. When administered in heterologous prime-boost regimens, AdC7-GRN and F4/AS01 candidate vaccines acted complementarily in inducing potent and persistent peripheral blood HIV-1-specific CD4(+) and CD8(+) T-cell responses and antibodies in macaques. Besides, adenoviral vector priming modulated the cytokine-expression profile of the protein-induced CD4(+) T cells. Each regimen induced HIV-1-specific T-cell responses in systemic/local tissues in mice. This suggests that prime-boost regimens combining adjuvanted protein and low-seroprevalent chimpanzee adenoviral vectors represent an attractive vaccination strategy for clinical evaluation. |
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