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Find video protocols related to scientific articles indexed in Pubmed.
Closure of the cytoplasmic gate formed by TM5 and TM11 during transport in the oxalate/formate exchanger from Oxalobacter formigenes.
Biochemistry
PUBLISHED: 11-20-2014
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OxlT, the oxalate/formate exchanger of Oxalobacter formigenes, is a member of the Major Facilitator Superfamily of transporters. In the present work, substrate (oxalate) was found to enhance the reactivity of the cysteine mutant S336C on the cytoplasmic end of helix 11 to methanethiosulfonate ethyl carboxylate. In addition, S336C is found to spontaneously cross-link to S143C in TM5 in either native or reconstituted membranes under conditions that support transport. Continuous wave EPR measurements are consistent with this result and indicate that positions 143 and 336 are in close proximity in the presence of substrate. These two residues are localized within helix interacting GxxxG-like motifs (G140LASG144 and S336DIFG340) at the cyto-plasmic poles of TM5 and TM11. Pulse EPR measurements were used to determine distances and distance distributions across the cytoplasmic or periplasmic ends of OxlT and were compared with the predictions of an inside-open homology model. The data indicate that a significant population of transporter is in an outside-open configuration in the presence of substrate; however, each end of the transporter exhibits significant conformational heterogeneity, where both inside-open and outside-open configurations are present. These data indicate that TM5 and TM11, which form part of the transport pathway, transiently close during transport, and that there is a conformational equilibrium between inside-open and outside-open states of OxlT in the presence of substrate.
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Dose-response for Starting and Stopping HIV Pre-Exposure Prophylaxis (PrEP) for MSM.
Clin. Infect. Dis.
PUBLISHED: 11-20-2014
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?This study estimated the number of daily tenofovir disoproxil fumarate/ emtricitabine (TDF/FTC) doses required to achieve and maintain (after discontinuation) intracellular drug concentrations that protect against HIV infection for men who have sex with men (MSM).
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Under-reporting of conflicts of interest among trialists: a cross-sectional study.
J R Soc Med
PUBLISHED: 11-13-2014
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To determine the prevalence of conflicts of interest (COIs) among Danish physicians who are authors of clinical drug trial reports and determine the extent of undisclosed COIs in trial publications.
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Simian Hemorrhagic Fever Virus Cell Entry is Dependent on CD163 and Uses a Clathrin-mediated Endocytosis-like Pathway.
J. Virol.
PUBLISHED: 10-31-2014
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Simian hemorrhagic fever virus (SHFV) causes a severe and almost uniformly fatal viral hemorrhagic fever in Asian macaques, but is thought to be nonpathogenic for humans. To date, the SHFV lifecycle is almost completely uncharacterized on the molecular level. Here we describe the first steps of the SHFV lifecycle. Our experiments indicate that SHFV enters target cells by low pH-dependent endocytosis. Dynamin inhibitors, chlorpromazine, methyl-?-cyclodextrin, chloroquine, and concanamycin A dramatically reduced SHFV entry efficiency, whereas the macropinocytosis inhibitors EIPA, blebbistatin, and wortmannin, and the caveolin-mediated endocytosis inhibitors nystatin and filipin III had no effect. Furthermore, overexpression and knock-out study and electron-microscopy results indicate that SHFV entry occurs by a dynamin-dependent clathrin-mediated endocytosis-like pathway. Experiments utilizing latrunculin B, cytochalasin B, and cytochalasin D indicate that SHFV does not hijack the actin polymerization pathway. Treatment of target cells with proteases (proteinase K, papain, ?-chymotrypsin, trypsin) abrogated entry, indicating that the SHFV cell-surface receptor is a protein. Phospholipases A2 and D had no effect on SHFV entry. Finally, treatment of cells with antibodies targeting CD163, a cell surface molecule identified as an entry factor for the SHFV-related porcine reproductive and respiratory syndrome virus, diminished SHFV replication, identifying CD163 as an important SHFV entry component.
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Our prescription drugs kill us in large numbers.
Pol. Arch. Med. Wewn.
PUBLISHED: 10-30-2014
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Our prescription drugs are the third leading cause of death after heart disease and cancer in the United States and Europe. Around half of those who die have taken their drugs correctly; the other half die because of errors, such as too high dose or use of a drug despite contraindications. Our drug agencies are not particularly helpful, as they rely on fake fixes, which are a long list of warnings, precautions and contraindications for each drug, although they know that no doctor can possible master all of these. Major reasons for the many drug deaths are impotent drug regulation, widespread crime that includes corruption of the scientific evidence about drugs and bribery of doctors, and lies in drug marketing, which is similar harmful as marketing of tobacco and therefore should be banned. We should take far fewer drugs, and patients should study carefully the package inserts of the drugs their doctors prescribe for them and independent information sources about drugs such as Cochrane reviews, which will make it easier for them to say no thanks.
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Tenofovir Diphosphate in Dried Blood Spots As an Objective Measure of Adherence in HIV-Infected Women.
AIDS Res. Hum. Retroviruses
PUBLISHED: 10-21-2014
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Abstract Simple and reproducible tools to assess antiretroviral adherence are needed. A level of tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) <1,250?fmol/punch is predicted to identify imperfect adherence. Herein we evaluated TFV-DP in DBS as a measure of adherence among HIV-infected women. DBS and peripheral blood mononuclear cells (PBMCs) were collected twice (?1 week apart) in 35 well-controlled HIV-infected women [median age 42 years, 14 African American/black (AA)] receiving daily coformulated tenofovir/emtricitabine and either atazanavir/ritonavir (n=20) or raltegravir (n=16). TFV-DP in DBS and PBMCs was quantified by LC-MS/MS. Six-month adherence was measured as average days between monthly pharmacy refills. Data were loge transformed for analysis and presented as median (range); the correlation between continuous variables was analyzed using the Pearson correlation coefficient. The average TFV-DP between the two visits (aTFV-DP) in DBS and PBMCs was 1,874 (706-3,776) fmol/punch and 125 (1-278) fmol/10(6) cells, respectively. AA women had lower levels of aTFV-DP in DBS compared to whites (1,660 vs. 1,970?fmol/punch; p=0.04), with a viremic patient having the lowest drug levels (706?fmol/punch). Days between pharmacy refills were 34 (30-54) vs. 30 (26-40) in women with TFV-DP in DBS <1,250 vs. ?1,250?fmol/punch (p=0.006). TFV-DP in DBS was negatively correlated with an increasing number of days between refills (r=-0.56, p=0.002). TFV-DP DBS was a reliable and objective measure of adherence in HIV-infected women based on a strong inverse relationship with pharmacy refill adherence.
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Genome Sequences of Simian Hemorrhagic Fever Virus Variant NIH LVR42-0/M6941 Isolates (Arteriviridae: Arterivirus).
Genome Announc
PUBLISHED: 10-11-2014
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Simian hemorrhagic fever virus (SHFV) variant NIH LVR42-0/M6941 is the only remaining SHFV in culture, and only a single genome sequence record exists in GenBank/RefSeq. We compared the genomic sequence of NIH LVR42-0/M6941 acquired from the ATCC in 2011 to NIH LVR42-0/M6941 genomes sequenced directly from nonhuman primates experimentally infected in 1989.
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Comparing the Novel Method of Assessing PrEP Adherence/Exposure using Hair Samples to other Pharmacologic and Traditional Measures.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 10-09-2014
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The efficacy of pre-exposure-prophylaxis (PrEP) in HIV can diminish with poor adherence; pharmacologic measures of drug exposure have proven critical to PrEP trial interpretation. We assessed drug exposure in hair against other pharmacologic and more routinely-used measures to assess pill-taking.
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Filovirus RefSeq entries: evaluation and selection of filovirus type variants, type sequences, and names.
Viruses
PUBLISHED: 09-17-2014
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Sequence determination of complete or coding-complete genomes of viruses is becoming common practice for supporting the work of epidemiologists, ecologists, virologists, and taxonomists. Sequencing duration and costs are rapidly decreasing, sequencing hardware is under modification for use by non-experts, and software is constantly being improved to simplify sequence data management and analysis. Thus, analysis of virus disease outbreaks on the molecular level is now feasible, including characterization of the evolution of individual virus populations in single patients over time. The increasing accumulation of sequencing data creates a management problem for the curators of commonly used sequence databases and an entry retrieval problem for end users. Therefore, utilizing the data to their fullest potential will require setting nomenclature and annotation standards for virus isolates and associated genomic sequences. The National Center for Biotechnology Information's (NCBI's) RefSeq is a non-redundant, curated database for reference (or type) nucleotide sequence records that supplies source data to numerous other databases. Building on recently proposed templates for filovirus variant naming [ ()////-], we report consensus decisions from a majority of past and currently active filovirus experts on the eight filovirus type variants and isolates to be represented in RefSeq, their final designations, and their associated sequences.
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Nystatin prophylaxis and treatment in severely immunodepressed patients.
Cochrane Database Syst Rev
PUBLISHED: 09-04-2014
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Nystatin is sometimes used prophylactically in patients with severe immunodeficiency or in the treatment of fungal infection in such patients, although its effect seems to be equivocal.
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Amphotericin B versus fluconazole for controlling fungal infections in neutropenic cancer patients.
Cochrane Database Syst Rev
PUBLISHED: 09-04-2014
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Systemic fungal infection is considered to be an important cause of morbidity and mortality in cancer patients, particularly those with neutropenia. Antifungal drugs are often given prophylactically, or empirically to patients with persistent fever.
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Routine versus selective antifungal administration for control of fungal infections in patients with cancer.
Cochrane Database Syst Rev
PUBLISHED: 09-04-2014
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Systemic fungal infection is considered to be an important cause of morbidity and mortality in cancer patients, particularly those with neutropenia. Antifungal drugs are often given prophylactically, or empirically to patients with persistent fever.
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Amphotericin B lipid soluble formulations versus amphotericin B in cancer patients with neutropenia.
Cochrane Database Syst Rev
PUBLISHED: 09-04-2014
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Patients with cancer who are treated with chemotherapy or receive a bone marrow transplant have an increased risk of acquiring fungal infections. Such infections can be life-threatening. Antifungal drugs are therefore often given prophylactically to such patients, or when they have a fever.
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Two Novel Simian Arteriviruses in Captive and Wild Baboons (Papio spp.).
J. Virol.
PUBLISHED: 09-03-2014
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Since the 1960s, simian hemorrhagic fever virus (SHFV; Nidovirales, Arteriviridae) has caused highly fatal outbreaks of viral hemorrhagic fever in captive Asian macaque colonies. However, the source(s) of these outbreaks and the natural reservoir(s) of this virus remain obscure. Here we report the identification of two novel, highly divergent simian arteriviruses related to SHFV, Mikumi yellow baboon virus 1 (MYBV-1) and Southwest baboon virus 1 (SWBV-1), in wild and captive baboons, respectively, and demonstrate the recent transmission of SWBV-1 among captive baboons. These findings extend our knowledge of the genetic and geographic diversity of the simian arteriviruses, identify baboons as a natural host of these viruses, and provide further evidence that baboons may have played a role in previous outbreaks of simian hemorrhagic fever in macaques, as has long been suspected. This knowledge should aid in the prevention of disease outbreaks in captive macaques and supports the growing body of evidence that suggests that simian arterivirus infections are common in Old World monkeys of many different species throughout Africa.
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Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): Explanation and elaboration.
Int J Surg
PUBLISHED: 07-22-2014
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Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies. The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies and cross-sectional studies and four are specific to each of the three study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers. This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, one or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated Web site (http://www.strobe-statement.org/) should be helpful resources to improve reporting of observational research.
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The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement: Guidelines for reporting observational studies.
Int J Surg
PUBLISHED: 07-22-2014
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Much biomedical research is observational. The reporting of such research is often inadequate, which hampers the assessment of its strengths and weaknesses and of a study's generalisability. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Initiative developed recommendations on what should be included in an accurate and complete report of an observational study. We defined the scope of the recommendations to cover three main study designs: cohort, case-control, and cross-sectional studies. We convened a 2-day workshop in September 2004, with methodologists, researchers, and journal editors to draft a checklist of items. This list was subsequently revised during several meetings of the coordinating group and in e-mail discussions with the larger group of STROBE contributors, taking into account empirical evidence and methodological considerations. The workshop and the subsequent iterative process of consultation and revision resulted in a checklist of 22 items (the STROBE Statement) that relate to the title, abstract, introduction, methods, results, and discussion sections of articles. 18 items are common to all three study designs and four are specific for cohort, case-control, or cross-sectional studies. A detailed Explanation and Elaboration document is published separately and is freely available on the Web sites of PLoS Medicine, Annals of Internal Medicine, and Epidemiology. We hope that the STROBE Statement will contribute to improving the quality of reporting of observational studies.
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Ebola virus modulates transforming growth factor ? signaling and cellular markers of mesenchyme-like transition in hepatocytes.
J. Virol.
PUBLISHED: 06-18-2014
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Ebola virus (EBOV) causes a severe hemorrhagic disease in humans and nonhuman primates, with a median case fatality rate of 78.4%. Although EBOV is considered a public health concern, there is a relative paucity of information regarding the modulation of the functional host response during infection. We employed temporal kinome analysis to investigate the relative early, intermediate, and late host kinome responses to EBOV infection in human hepatocytes. Pathway overrepresentation analysis and functional network analysis of kinome data revealed that transforming growth factor (TGF-?)-mediated signaling responses were temporally modulated in response to EBOV infection. Upregulation of TGF-? signaling in the kinome data sets correlated with the upregulation of TGF-? secretion from EBOV-infected cells. Kinase inhibitors targeting TGF-? signaling, or additional cell receptors and downstream signaling pathway intermediates identified from our kinome analysis, also inhibited EBOV replication. Further, the inhibition of select cell signaling intermediates identified from our kinome analysis provided partial protection in a lethal model of EBOV infection. To gain perspective on the cellular consequence of TGF-? signaling modulation during EBOV infection, we assessed cellular markers associated with upregulation of TGF-? signaling. We observed upregulation of matrix metalloproteinase 9, N-cadherin, and fibronectin expression with concomitant reductions in the expression of E-cadherin and claudin-1, responses that are standard characteristics of an epithelium-to-mesenchyme-like transition. Additionally, we identified phosphorylation events downstream of TGF-? that may contribute to this process. From these observations, we propose a model for a broader role of TGF-?-mediated signaling responses in the pathogenesis of Ebola virus disease.
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Coding of adverse events of suicidality in clinical study reports of duloxetine for the treatment of major depressive disorder: descriptive study.
BMJ
PUBLISHED: 06-06-2014
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To assess the effects of coding and coding conventions on summaries and tabulations of adverse events data on suicidality within clinical study reports.
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Benefits and harms in clinical trials of duloxetine for treatment of major depressive disorder: comparison of clinical study reports, trial registries, and publications.
BMJ
PUBLISHED: 06-06-2014
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To determine, using research on duloxetine for major depressive disorder as an example, if there are inconsistencies between protocols, clinical study reports, and main publicly available sources (journal articles and trial registries), and within clinical study reports themselves, with respect to benefits and major harms.
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Tenofovir diphosphate concentrations and prophylactic effect in a macaque model of rectal simian HIV transmission.
J. Antimicrob. Chemother.
PUBLISHED: 05-26-2014
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This study evaluated the relationship between intracellular tenofovir diphosphate concentrations in peripheral blood mononuclear cells and prophylactic efficacy in a macaque model for HIV pre-exposure prophylaxis (PrEP).
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Study product adherence measurement in the iPrEx placebo-controlled trial: concordance with drug detection.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 05-24-2014
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To evaluate the concordance between adherence estimated by self-report (in-person interview or computer-assisted self-interview), in-clinic pill counts, and pharmacy dispensation records and drug detection among participants in a placebo-controlled pre-exposure prophylaxis HIV prevention trial (iPrEx).
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Repurposing of clinically developed drugs for treatment of Middle East respiratory syndrome coronavirus infection.
Antimicrob. Agents Chemother.
PUBLISHED: 05-19-2014
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Outbreaks of emerging infections present health professionals with the unique challenge of trying to select appropriate pharmacologic treatments in the clinic with little time available for drug testing and development. Typically, clinicians are left with general supportive care and often untested convalescent-phase plasma as available treatment options. Repurposing of approved pharmaceutical drugs for new indications presents an attractive alternative to clinicians, researchers, public health agencies, drug developers, and funding agencies. Given the development times and manufacturing requirements for new products, repurposing of existing drugs is likely the only solution for outbreaks due to emerging viruses. In the studies described here, a library of 290 compounds was screened for antiviral activity against Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus (SARS-CoV). Selection of compounds for inclusion in the library was dependent on current or previous FDA approval or advanced clinical development. Some drugs that had a well-defined cellular pathway as target were included. In total, 27 compounds with activity against both MERS-CoV and SARS-CoV were identified. The compounds belong to 13 different classes of pharmaceuticals, including inhibitors of estrogen receptors used for cancer treatment and inhibitors of dopamine receptor used as antipsychotics. The drugs identified in these screens provide new targets for in vivo studies as well as incorporation into ongoing clinical studies.
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HIV-1 drug resistance in the iPrEx preexposure prophylaxis trial.
J. Infect. Dis.
PUBLISHED: 04-16-2014
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The iPrEx study demonstrated that combination oral emtricitabine and tenofovir disoproxil fumarate (FTC/TDF) as preexposure prophylaxis (PrEP) protects against HIV acquisition in men who have sex with men and transgender women. Selection for drug resistance could offset PrEP benefits.
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The NIAID Integrated Research Facility at Frederick, Maryland: a unique international resource to facilitate medical countermeasure development for BSL-4 pathogens.
Pathog Dis
PUBLISHED: 03-14-2014
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Scientists at the National Institute of Allergy and Infectious Diseases Integrated Research Facility at Fort Detrick, Frederick, Maryland, coordinate and facilitate preclinical research on infectious diseases to develop medical countermeasures for high-consequence pathogens. This facility is unique in that it is the only maximum containment laboratory in the world where conventional and molecular medical imaging equipments are incorporated into the design of the facility. This capability provides investigators with unique tools to dissect disease pathogenesis, evaluate the ability of animal models to recapitulate human disease, and test candidate countermeasures. Importantly, advanced molecular imaging has the potential to provide alternative endpoints to lethality. Using these alternative endpoints, investigators can reduce the number of animals used in experiments and evaluate countermeasures in sublethal models. With the incorporation of medical imaging modalities, a clinical laboratory modeled after those existing in hospitals, and a highly trained veterinary medicine team, IRF-Frederick is uniquely suited to advance our understanding of emerging infectious diseases and to facilitate the development of medical countermeasures and clinical care paradigms previously considered impossible.
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Voriconazole versus amphotericin B or fluconazole in cancer patients with neutropenia.
Cochrane Database Syst Rev
PUBLISHED: 02-25-2014
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Opportunistic fungal infections are a major cause of morbidity and mortality in neutropenic cancer patients and antifungal therapy is used both empirically and therapeutically in these patients.
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Systems kinomics for characterizing host responses to high-consequence pathogens at the NIH/NIAID Integrated Research Facility-Frederick.
Pathog Dis
PUBLISHED: 02-04-2014
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Currently, there is a paucity of information regarding the molecular pathogenesis for many high-consequence pathogens (HCPs) that pose threats to both national and international public health. In spite of this, investigations of the molecular pathogenesis for many HCPs have been limited to gross pathological changes in animal models or global analysis of gene expression. Further, questions remain regarding the ability of animal models of disease to recapitulate human molecular pathogenesis or act as predictors of therapeutic efficacy. Thus, it is likely that medical countermeasure development for HCPs will rely on identifying therapeutic targets that are uniquely modulated during HCP infection. It is also appreciated that many cellular processes can be regulated independently of changes in transcription or translation through phosphorylation events. Cellular kinases, individually or collectively (the kinome), play critical roles in regulating complex biology, underlie various malignancies, and represent high-priority drug targets. The growing interest in kinases in both basic and translational research has driven efforts to develop technologies that enable characterization of phosphorylation-mediated signal transduction. To this end, enhanced technical capabilities at the IRF-Frederick provide the unique capability for characterizing host responses to HCP insult during the course of infection and identify novel targets for therapeutic intervention.
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Lead-time models should not be used to estimate overdiagnosis in cancer screening.
J Gen Intern Med
PUBLISHED: 01-27-2014
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Lead-time can mean two different things: Clinical lead-time is the lead-time for clinically relevant tumors; that is, those that are not overdiagnosed. Model-based lead-time is a theoretical construct where the time when the tumor would have caused symptoms is not limited by the person's death. It is the average time at which the diagnosis is brought forward for both clinically relevant and overdiagnosed cancers. When screening for breast cancer, clinical lead-time is about 1 year, while model-based lead-time varies from 2 to 7 years. There are two different methods to calculate overdiagnosis in cancer screening--the excess-incidence approach and the lead-time approach--that rely on two different lead-time definitions. Overdiagnosis when screening with mammography has varied from 0 to 75 %. We have explained that these differences are mainly caused by using different definitions and methods and not by variations in data. High levels of overdiagnosis of cancer have usually been explained by detection of many slow-growing tumors with long lead-times. This theory can be tested by studying if slow-growing tumors accumulate in the absence of screening, which they don't. Thus, it is likely that the natural history of many subclinical cancers is spontaneous regression.
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Validation of a sensitive LC/MS/MS method for the determination of telaprevir and its R-isomer in human plasma.
Biomed. Chromatogr.
PUBLISHED: 01-24-2014
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The purpose of this study was to validate a reversed-phase high-performance liquid chromatographic (HPLC), tandem mass spectrometry (MS/MS) assay for the determination of telaprevir and its R-diastereomer (VRT-127394) in acidified and nonacidified human plasma. The chromatographic baseline separation of telaprevir and telaprevir-R was performed on a Waters XBridge(TM) BEH Shield C18 , 2.1?×?75?mm column with a 2.5?µm particle size, under isocratic conditions consisting of a mobile phase of 50:45:5 water-acetonitrile-isopropanol with 1% ammonia at 0.2?mL/min. This method utilized a stable isotope internal standard with 11 deuterium atoms on the structure of the telaprevir molecule (telaprevir-d11). An internal standard for the telaprevir-R (telaprevir-R-d11) was also prepared by incubating telaprevir-d11 in basic solution, which facilitated isomer inter-conversion. The detection and quantitation of telaprevir, telaprevir-R, telaprevir-IS and telaprevir-R-IS was achieved by positive ion electrospray (ESI+) MS/MS detection. The assay quantifiable limit was 5.0?ng/mL when 0.100?mL of acidified human plasma was extracted. Accuracy and precision were validated over the calibration range of 5.0-5000?ng/mL. It was demonstrated using patient samples that, contrary to previous recommendations, quantitation of telaprevir does not require acidified plasma. Copyright © 2014 John Wiley & Sons, Ltd.
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ABSL-4 aerobiology biosafety and technology at the NIH/NIAID integrated research facility at Fort Detrick.
Viruses
PUBLISHED: 01-10-2014
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The overall threat of a viral pathogen to human populations is largely determined by the modus operandi and velocity of the pathogen that is transmitted among humans. Microorganisms that can spread by aerosol are considered a more challenging enemy than those that require direct body-to-body contact for transmission, due to the potential for infection of numerous people rather than a single individual. Additionally, disease containment is much more difficult to achieve for aerosolized viral pathogens than for pathogens that spread solely via direct person-to-person contact. Thus, aerobiology has become an increasingly necessary component for studying viral pathogens that are naturally or intentionally transmitted by aerosol. The goal of studying aerosol viral pathogens is to improve public health preparedness and medical countermeasure development. Here, we provide a brief overview of the animal biosafety level 4 Aerobiology Core at the NIH/NIAID Integrated Research Facility at Fort Detrick, Maryland, USA.
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Increasing value and reducing waste: addressing inaccessible research.
Lancet
PUBLISHED: 01-08-2014
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The methods and results of health research are documented in study protocols, full study reports (detailing all analyses), journal reports, and participant-level datasets. However, protocols, full study reports, and participant-level datasets are rarely available, and journal reports are available for only half of all studies and are plagued by selective reporting of methods and results. Furthermore, information provided in study protocols and reports varies in quality and is often incomplete. When full information about studies is inaccessible, billions of dollars in investment are wasted, bias is introduced, and research and care of patients are detrimentally affected. To help to improve this situation at a systemic level, three main actions are warranted. First, academic institutions and funders should reward investigators who fully disseminate their research protocols, reports, and participant-level datasets. Second, standards for the content of protocols and full study reports and for data sharing practices should be rigorously developed and adopted for all types of health research. Finally, journals, funders, sponsors, research ethics committees, regulators, and legislators should endorse and enforce policies supporting study registration and wide availability of journal reports, full study reports, and participant-level datasets.
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CD26/DPP4 Cell-Surface Expression in Bat Cells Correlates with Bat Cell Susceptibility to Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Infection and Evolution of Persistent Infection.
PLoS ONE
PUBLISHED: 01-01-2014
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Middle East respiratory syndrome coronavirus (MERS-CoV) is a recently isolated betacoronavirus identified as the etiologic agent of a frequently fatal disease in Western Asia, Middle East respiratory syndrome. Attempts to identify the natural reservoirs of MERS-CoV have focused in part on dromedaries. Bats are also suspected to be reservoirs based on frequent detection of other betacoronaviruses in these mammals. For this study, ten distinct cell lines derived from bats of divergent species were exposed to MERS-CoV. Plaque assays, immunofluorescence assays, and transmission electron microscopy confirmed that six bat cell lines can be productively infected. We found that the susceptibility or resistance of these bat cell lines directly correlates with the presence or absence of cell surface-expressed CD26/DPP4, the functional human receptor for MERS-CoV. Human anti-CD26/DPP4 antibodies inhibited infection of susceptible bat cells in a dose-dependent manner. Overexpression of human CD26/DPP4 receptor conferred MERS-CoV susceptibility to resistant bat cell lines. Finally, sequential passage of MERS-CoV in permissive bat cells established persistent infection with concomitant downregulation of CD26/DPP4 surface expression. Together, these results imply that bats indeed could be among the MERS-CoV host spectrum, and that cellular restriction of MERS-CoV is determined by CD26/DPP4 expression rather than by downstream restriction factors.
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Comparison of Results from Different Imputation Techniques for Missing Data from an Anti-Obesity Drug Trial.
PLoS ONE
PUBLISHED: 01-01-2014
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In randomised trials of medical interventions, the most reliable analysis follows the intention-to-treat (ITT) principle. However, the ITT analysis requires that missing outcome data have to be imputed. Different imputation techniques may give different results and some may lead to bias. In anti-obesity drug trials, many data are usually missing, and the most used imputation method is last observation carried forward (LOCF). LOCF is generally considered conservative, but there are more reliable methods such as multiple imputation (MI).
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Strong relationship between oral dose and tenofovir hair levels in a randomized trial: hair as a potential adherence measure for pre-exposure prophylaxis (PrEP).
PLoS ONE
PUBLISHED: 01-01-2014
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Pre-exposure prophylaxis (PrEP) trials using tenofovir-based regimens have demonstrated that high levels of adherence are required to evaluate efficacy; the incorporation of objective biomarkers of adherence in trial design has been essential to interpretation, given the inaccuracy of self-report. Antiretroviral measurements in scalp hair have been useful as a marker of long-term exposure in the HIV treatment setting, and hair samples are relatively easy and inexpensive to collect, transport, and store for analysis. To evaluate the relationship between dose and tenofovir concentrations in hair, we examined the dose proportionality of tenofovir in hair in healthy, HIV-uninfected adults.
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Interferon-beta and mycophenolic acid are potent inhibitors of Middle East respiratory syndrome coronavirus in cell-based assays.
J. Gen. Virol.
PUBLISHED: 12-09-2013
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The Middle East respiratory syndrome coronavirus (MERS-CoV) presents a novel emerging threat to public health worldwide. Several treatments for infected individuals have been suggested including interferon (IFN), ribavirin, and passive immunotherapy with convalescent plasma. Administration of IFN-?2b and ribavirin has improved outcomes of MERS-CoV infection in rhesus macaques when administered within eight hours post challenge. However, detailed and systematic evidence on the activity of other clinically available drugs is limited. Here we compared the susceptibility of MERS-CoV to different interferon products (IFN-?2b, IFN-?, IFN-universal, and IFN-?2a, IFN-?) as well as to two antivirals, ribavirin and mycophenolic acid (MPA) against MERS-CoV (Hu/Jordan-N3/2012) in vitro. Out of all IFNs tested, IFN-? had the strongest inhibition of MERS-CoV in vitro, with an IC50 of 1.37 U ml-1, 41 times lower than the previously reported IC50 (56.08 U ml-1) of IFN-?2b. IFN-? inhibition was confirmed in the virus yield reduction assay with an IC90 of 38.8 U ml-1. Ribavirin did not inhibit viral replication in vitro at a dose that would be applicable to current treatment protocols in humans. In contrast, MPA showed strong inhibition with an IC50 = 2.87 µM. This drug has not been previously tested against MERS-CoV and may provide an alternative to ribavirin for treatment of MERS-CoV. In conclusion, IFN-?, MPA, or a combination of the two may be beneficial in the treatment of MERS-CoV or as a post exposure intervention in high risk patients with known exposures to MERS-CoV.
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Nonhuman transferrin receptor 1 is an efficient cell entry receptor for ocozocoautla de espinosa virus.
J. Virol.
PUBLISHED: 10-09-2013
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Ocozocoautla de Espinosa virus (OCEV) is a novel, uncultured arenavirus. We found that the OCEV glycoprotein mediates entry into grivet and bat cells through transferrin receptor 1 (TfR1) binding but that OCEV glycoprotein precursor (GPC)-pseudotyped retroviruses poorly entered 53 human cancer cell lines. Interestingly, OCEV and Tacaribe virus could use bat, but not human, TfR1. Replacing three human TfR1 amino acids with their bat ortholog counterparts transformed human TfR1 into an efficient OCEV and Tacaribe virus receptor.
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Dependence and withdrawal reactions to benzodiazepines and selective serotonin reuptake inhibitors. How did the health authorities react?
Int J Risk Saf Med
PUBLISHED: 09-20-2013
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Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time.
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Development and validation of a dried blood spot assay for the quantification of ribavirin using liquid chromatography coupled to mass spectrometry.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 08-15-2013
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Efficient, inexpensive and sensitive assays for the measurement of drugs are of interest for pharmacokinetic and pharmacodynamics (PK-PD) analysis. Dried blood spots (DBS) are a unique bioanaltyical matrix with the potential to fulfill this interest for the measurement of numerous analytes. Here we describe the development and validation of a reversed-phase high performance liquid chromatographic (LC), tandem mass spectrometry (MS/MS) assay for the determination of ribavirin (RBV) in DBS. A 3mm punch from spotted and dried whole blood was extracted in methanol utilizing isotopically labeled internal standard for LC-MS/MS analysis. Validation was performed over a range of 0.05?g/mL to 10.0?g/mL and the method was shown to be precise (coefficient of variation ?15%) and accurate (within ±15% of control). These acceptance criteria were met for hematocrit ranges of 20-54%, for center versus edge punches and for spot volumes from 10 to 60?L. RBV was stable for up to 140 days at room temperature and -20°C as well as for three freeze/thaw cycles. Correlation of RBV in DBS versus in plasma yielded r(2)?0.98 demonstrating that DBS can be used as an alternative to plasma for PK-PD studies in human subjects.
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Virus nomenclature below the species level: a standardized nomenclature for filovirus strains and variants rescued from cDNA.
Arch. Virol.
PUBLISHED: 07-24-2013
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Specific alterations (mutations, deletions, insertions) of virus genomes are crucial for the functional characterization of their regulatory elements and their expression products, as well as a prerequisite for the creation of attenuated viruses that could serve as vaccine candidates. Virus genome tailoring can be performed either by using traditionally cloned genomes as starting materials, followed by site-directed mutagenesis, or by de novo synthesis of modified virus genomes or parts thereof. A systematic nomenclature for such recombinant viruses is necessary to set them apart from wild-type and laboratory-adapted viruses, and to improve communication and collaborations among researchers who may want to use recombinant viruses or create novel viruses based on them. A large group of filovirus experts has recently proposed nomenclatures for natural and laboratory animal-adapted filoviruses that aim to simplify the retrieval of sequence data from electronic databases. Here, this work is extended to include nomenclature for filoviruses obtained in the laboratory via reverse genetics systems. The previously developed template for natural filovirus genetic variant naming, (/)///-, is retained, but we propose to adapt the type of information added to each field for cDNA clone-derived filoviruses. For instance, the full-length designation of an Ebola virus Kikwit variant rescued from a plasmid developed at the US Centers for Disease Control and Prevention could be akin to "Ebola virus H.sapiens-rec/COD/1995/Kikwit-abc1" (with the suffix "rec" identifying the recombinant nature of the virus and "abc1" being a placeholder for any meaningful isolate designator). Such a full-length designation should be used in databases and the methods section of publications. Shortened designations (such as "EBOV H.sap/COD/95/Kik-abc1") and abbreviations (such as "EBOV/Kik-abc1") could be used in the remainder of the text, depending on how critical it is to convey information contained in the full-length name. "EBOV" would suffice if only one EBOV strain/variant/isolate is addressed.
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Characterizing monkeypox virus specific CD8+ T cell epitopes in rhesus macaques.
Virology
PUBLISHED: 07-08-2013
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To characterize T cell epitopes in monkeypox virus (MPXV) infected rhesus macaques, we utilized IFN? Elispot assay to screen 400 predicted peptides from 20MPXV proteins. Two peptides from the F8L protein, an analog of E9L protein in vaccinia, were found to elicit CD8+ T cell responses. Prediction and in vitro MHC binding analyses suggest that one is restricted by Mamu-A1(?)001 and another by Mamu-A1(?)002. The Mamu-A1(?)002 epitope is completely identical in all reported sequences for variola, vaccinia, cowpox and MPXV. The Mamu-A1(?)001 epitope is conserved in MPXV and vaccinia, and has one residue substitution (V6>I) in some cowpox sequences and all variola sequences. Given CD8+ T-cell epitopes from E9L were also identified in humans and mice, our data suggested that F8L/E9L may be a dominant pox viral protein for CD8+ T cell responses, and may be considered as a target when designing vaccines that target pox-specific T cell responses.
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Endothelial cell permeability during hantavirus infection involves factor XII-dependent increased activation of the kallikrein-kinin system.
PLoS Pathog.
PUBLISHED: 07-01-2013
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Hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS) are diseases caused by hantavirus infections and are characterized by vascular leakage due to alterations of the endothelial barrier. Hantavirus-infected endothelial cells (EC) display no overt cytopathology; consequently, pathogenesis models have focused either on the influx of immune cells and release of cytokines or on increased degradation of the adherens junction protein, vascular endothelial (VE)-cadherin, due to hantavirus-mediated hypersensitization of EC to vascular endothelial growth factor (VEGF). To examine endothelial leakage in a relevant in vitro system, we co-cultured endothelial and vascular smooth muscle cells (vSMC) to generate capillary blood vessel-like structures. In contrast to results obtained in monolayers of cultured EC, we found that despite viral replication in both cell types as well as the presence of VEGF, infected in vitro vessels neither lost integrity nor displayed evidence of VE-cadherin degradation. Here, we present evidence for a novel mechanism of hantavirus-induced vascular leakage involving activation of the plasma kallikrein-kinin system (KKS). We show that incubation of factor XII (FXII), prekallikrein (PK), and high molecular weight kininogen (HK) plasma proteins with hantavirus-infected EC results in increased cleavage of HK, higher enzymatic activities of FXIIa/kallikrein (KAL) and increased liberation of bradykinin (BK). Measuring cell permeability in real-time using electric cell-substrate impedance sensing (ECIS), we identified dramatic increases in endothelial cell permeability after KKS activation and liberation of BK. Furthermore, the alterations in permeability could be prevented using inhibitors that directly block BK binding, the activity of FXIIa, or the activity of KAL. Lastly, FXII binding and autoactivation is increased on the surface of hantavirus-infected EC. These data are the first to demonstrate KKS activation during hantavirus infection and could have profound implications for treatment of hantavirus infections.
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General health checks in adults for reducing morbidity and mortality from disease.
JAMA
PUBLISHED: 06-20-2013
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What are the benefits and harms of general health checks for adult populations?
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Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis..
Cochrane Database Syst Rev
PUBLISHED: 06-18-2013
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Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed.
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Quantitation of tenofovir and emtricitabine in dried blood spots (DBS) with LC-MS/MS.
J Pharm Biomed Anal
PUBLISHED: 06-14-2013
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A reversed-phase high performance liquid chromatographic (LC), tandem mass spectrometry (MS/MS) assay for the determination of tenofovir (TFV) and emtricitabine (FTC) in dried blood spots (DBS) from human whole blood was developed and validated. Whole blood samples were spotted, dried, and a 3mm punch was extracted with methanol for analysis by LC-MS/MS utilizing stable isotope labeled internal standards. The assay was validated over the range of 2.5-1000ng/mL for TFV and 2.5-5000ng/mL for FTC. The method was accurate (within ±15% of control) and precise (coefficient of variation ?15%) for hematocrit concentrations ranging from 25% to 76%; using edge punches vs. center punches; and spot volumes of 10-50?L. Analytes were stable for five freeze/thaw cycles and up to 6 days at room temperature, whereas long-term storage required -20°C or -80°C. Comparison of TFV and FTC in DBS vs. plasma yielded r(2)?0.96, indicating that DBS can be used as a plasma alternative for pharmacokinetic analyses in vivo.
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Screening for breast cancer with mammography.
Cochrane Database Syst Rev
PUBLISHED: 06-06-2013
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A variety of estimates of the benefits and harms of mammographic screening for breast cancer have been published and national policies vary.
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Citations of scientific results and conflicts of interest: the case of mammography screening.
Evid Based Med
PUBLISHED: 05-01-2013
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In 2001, a Cochrane review of mammography screening questioned whether screening reduces breast cancer mortality, and a more comprehensive review in Lancet, also in 2001, reported considerable overdiagnosis and overtreatment. This led to a heated debate and a recent review of the evidence by UK experts intended to be independent.
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Searching for unpublished data for Cochrane reviews: cross sectional study.
BMJ
PUBLISHED: 04-25-2013
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To describe the experiences of authors of Cochrane reviews in searching for, getting access to, and using unpublished data.
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Underreporting of conflicts of interest in clinical practice guidelines: cross sectional study.
BMC Med Ethics
PUBLISHED: 04-24-2013
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Conflicts of interest affect recommendations in clinical guidelines and disclosure of such conflicts is important. However, not all conflicts of interest are disclosed. Using a public available disclosure list we determined the prevalence and underreporting of conflicts of interest among authors of clinical guidelines on drug treatments.
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PRISMA for Abstracts: reporting systematic reviews in journal and conference abstracts.
PLoS Med.
PUBLISHED: 04-01-2013
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Elaine Beller and colleagues from the PRISMA for Abstracts group provide a reporting guidelines for reporting abstracts of systematic reviews in journals and at conferences.
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Clinical pharmacokinetics of antiretroviral drugs in older persons.
Expert Opin Drug Metab Toxicol
PUBLISHED: 03-20-2013
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Combination antiretroviral therapy has enabled HIV-infected persons to reach older ages in high numbers. Hepatic and renal changes that normally occur with advancing age occur earlier and with higher incidence in HIV-infected individuals. A limited number of prospective controlled studies have demonstrated small reductions (17 to 41%) in lopinavir, atazanavir and lamivudine clearance in older versus younger adults. A much larger number of retrospective studies in adults (age range ? 20 to 60 years), including all antiretroviral drugs, have evaluated age as a covariate for pharmacokinetics. Most studies did not detect substantial associations between drug exposures and age.
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Gout-causing Q141K mutation in ABCG2 leads to instability of the nucleotide-binding domain and can be corrected with small molecules.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 03-14-2013
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The multidrug ATP-binding cassette, subfamily G, 2 (ABCG2) transporter was recently identified as an important human urate transporter, and a common mutation, a Gln to Lys substitution at position 141 (Q141K), was shown to cause hyperuricemia and gout. The nature of the Q141K defect, however, remains undefined. Here we explore the Q141K ABCG2 mutation using a comparative approach, contrasting it with another disease-causing mutation in an ABC transporter, the deletion of Phe-508 (?F508) in the cystic fibrosis transmembrane conductance regulator (CFTR). We found, much like in ?F508 CFTR, that the Q141K mutation leads to instability in the nucleotide-binding domain (NBD), a defect that translates to significantly decreased protein expression. However, unlike the CFTR mutant, the Q141K mutation does not interfere with the nucleotide-binding domain/intracellular loop interactions. This investigation has also led to the identification of critical residues involved in the protein-protein interactions necessary for the dimerization of ABCG2: Lys-473 (K473) and Phe-142 (F142). Finally, we have demonstrated the utility of using small molecules to correct the Q141K defect in expression and function as a possible therapeutic approach for hyperuricemia and gout.
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Poxvirus antigen staining of immune cells as a biomarker to predict disease outcome in monkeypox and cowpox virus infection in non-human primates.
PLoS ONE
PUBLISHED: 02-27-2013
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Infection of non-human primates (NHPs) such as rhesus and cynomolgus macaques with monkeypox virus (MPXV) or cowpox virus (CPXV) serve as models to study poxvirus pathogenesis and to evaluate vaccines and anti-orthopox therapeutics. Intravenous inoculation of macaques with high dose of MPXV (>1-2×10(7) PFU) or CPXV (>10(2) PFU) results in 80% to 100% mortality and 66 to 100% mortality respectively. Here we report that NHPs with positive detection of poxvirus antigens in immune cells by flow cytometric staining, especially in monocytes and granulocytes succumbed to virus infection and that early positive pox staining is a strong predictor for lethality. Samples from four independent studies were analyzed. Eighteen NHPs from three different experiments were inoculated with two different MPXV strains at lethal doses. Ten NHPs displayed positive pox-staining and all 10 NHPs reached moribund endpoint. In contrast, none of the three NHPs that survived anticipated lethal virus dose showed apparent virus staining in the monocytes and granulocytes. In addition, three NHPs that were challenged with a lethal dose of MPXV and received cidofovir treatment were pox-antigen negative and all three NHPs survived. Furthermore, data from a CPXV study also demonstrated that 6/9 NHPs were pox-antigen staining positive and all 6 NHPs reached euthanasia endpoint, while the three survivors were pox-antigen staining negative. Thus, we conclude that monitoring pox-antigen staining in immune cells can be used as a biomarker to predict the prognosis of virus infection. Future studies should focus on the mechanisms and implications of the pox-infection of immune cells and the correlation between pox-antigen detection in immune cells and disease progression in human poxviral infection.
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The International Code of Virus Classification and Nomenclature (ICVCN): proposal for text changes for improved differentiation of viral taxa and viruses.
Arch. Virol.
PUBLISHED: 02-16-2013
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The International Committee on Taxonomy of Viruses (ICTV) is responsible for the classification of viruses into taxa. Importantly, the ICTV is currently not responsible for the nomenclature of viruses or their subclassification into strains, lineages, or genotypes. ICTV rules for classification of viruses and nomenclature of taxa are laid out in a code, the International Code of Virus Classification and Nomenclature (ICVCN). The most recent version of the Code makes it difficult for the unfamiliar reader to distinguish between viruses and taxa, thereby often giving the impression that certain Rules apply to viruses. Here, Code text changes are proposed to address this problem.
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Nyamiviridae: proposal for a new family in the order Mononegavirales.
Arch. Virol.
PUBLISHED: 02-12-2013
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Nyamanini virus (NYMV) and Midway virus (MIDWV) are unclassified tick-borne agents that infect land birds and seabirds, respectively. The recent molecular characterization of both viruses confirmed their already known close serological relationship and revealed them to be nonsegmented, single- and negative-stranded RNA viruses that are clearly related to, but quite distinct from, members of the order Mononegavirales (bornaviruses, filoviruses, paramyxoviruses, and rhabdoviruses). A third agent, soybean cyst nematode virus 1 (SbCNV-1, previously named soybean cyst nematode nyavirus), was recently found to be an additional member of this new virus group. Here, we review the current knowledge about all three viruses and propose classifying them as members of a new mononegaviral family, Nyamiviridae.
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Strategies for obtaining unpublished drug trial data: a qualitative interview study.
Syst Rev
PUBLISHED: 01-24-2013
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Authors of systematic reviews have difficulty obtaining unpublished data for their reviews. This project aimed to provide an in-depth description of the experiences of authors in searching for and gaining access to unpublished data for their systematic reviews, and to give guidance on best practices for identifying, obtaining and using unpublished data.
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Monkeypox virus infection of rhesus macaques induces massive expansion of natural killer cells but suppresses natural killer cell functions.
PLoS ONE
PUBLISHED: 01-01-2013
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Natural killer (NK) cells play critical roles in innate immunity and in bridging innate and adaptive immune responses against viral infection. However, the response of NK cells to monkeypox virus (MPXV) infection is not well characterized. In this intravenous challenge study of MPXV infection in rhesus macaques (Macaca mulatta), we analyzed blood and lymph node NK cell changes in absolute cell numbers, cell proliferation, chemokine receptor expression, and cellular functions. Our results showed that the absolute number of total NK cells in the blood increased in response to MPXV infection at a magnitude of 23-fold, manifested by increases in CD56+, CD16+, CD16-CD56- double negative, and CD16+CD56+ double positive NK cell subsets. Similarly, the frequency and NK cell numbers in the lymph nodes also largely increased with the total NK cell number increasing 46.1-fold. NK cells both in the blood and lymph nodes massively proliferated in response to MPXV infection as measured by Ki67 expression. Chemokine receptor analysis revealed reduced expression of CXCR3, CCR7, and CCR6 on NK cells at early time points (days 2 and 4 after virus inoculation), followed by an increased expression of CXCR3 and CCR5 at later time points (days 7-8) of infection. In addition, MPXV infection impaired NK cell degranulation and ablated secretion of interferon-? and tumor necrosis factor-?. Our data suggest a dynamic model by which NK cells respond to MPXV infection of rhesus macaques. Upon virus infection, NK cells proliferated robustly, resulting in massive increases in NK cell numbers. However, the migrating capacity of NK cells to tissues at early time points might be reduced, and the functions of cytotoxicity and cytokine secretion were largely compromised. Collectively, the data may explain, at least partially, the pathogenesis of MPXV infection in rhesus macaques.
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Systems kinomics demonstrates Congo Basin monkeypox virus infection selectively modulates host cell signaling responses as compared to West African monkeypox virus.
Mol. Cell Proteomics
PUBLISHED: 12-28-2011
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Monkeypox virus (MPXV) is comprised of two clades: Congo Basin MPXV, with an associated case fatality rate of 10%, and Western African MPXV, which is associated with less severe infection and minimal lethality. We thus postulated that Congo Basin and West African MPXV would differentially modulate host cell responses and, as many host responses are regulated through phosphorylation independent of transcription or translation, we employed systems kinomics with peptide arrays to investigate these functional host responses. Using this approach we have demonstrated that Congo Basin MPXV infection selectively down-regulates host responses as compared with West African MPXV, including growth factor- and apoptosis-related responses. These results were confirmed using fluorescence-activated cell sorting analysis demonstrating that West African MPXV infection resulted in a significant increase in apoptosis in human monocytes as compared with Congo Basin MPXV. Further, differentially phosphorylated kinases were identified through comparison of our MPXV data sets and validated as potential targets for pharmacological inhibition of Congo Basin MPXV infection, including increased Akt S473 phosphorylation and decreased p53 S15 phosphorylation. Inhibition of Akt S473 phosphorylation resulted in a significant decrease in Congo Basin MPXV virus yield (261-fold) but did not affect West African MPXV. In addition, treatment with staurosporine, an apoptosis activator resulted in a 49-fold greater decrease in Congo Basin MPXV yields as compared with West African MPXV. Thus, using a systems kinomics approach, our investigation demonstrates that West African and Congo Basin MPXV differentially modulate host cell responses and has identified potential host targets of therapeutic interest.
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Influence of SLCO1B1 polymorphisms on the drug-drug interaction between darunavir/ritonavir and pravastatin.
J Clin Pharmacol
PUBLISHED: 12-14-2011
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The authors investigated whether SLCO1B1 polymorphisms contribute to variability in pravastatin pharmacokinetics when pravastatin is administered alone versus with darunavir/ritonavir. HIV-negative healthy participants were prospectively enrolled on the basis of SLCO1B1 diplotype: group 1 (*1A/*1A, n = 9); group 2 (*1A/*1B, n = 10; or *1B/*1B, n = 2); and group 3 (*1A/*15, n = 1; *1B/*15, n = 5; or *1B/*17, n = 1). Participants received pravastatin (40 mg) daily on days 1 through 4, washout on days 5 through 11, darunavir/ritonavir (600/100 mg) twice daily on days 12 through 18, with pravastatin 40 mg added back on days 15 through 18. Pharmacokinetic studies were conducted on day 4 (pravastatin alone) and day 18 (pravastatin + darunavir/ritonavir). Pravastatin area under the plasma concentration-time curve (AUC(tau)) was 21% higher during administration with darunavir/ritonavir compared with pravastatin alone; however, this difference was not statistically significant (P = .11). Group 3 variants had 96% higher pravastatin AUC(tau) on day 4 and 113% higher pravastatin AUC(tau) on day 18 compared with group 1. The relative change in pravastatin pharmacokinetics was largest in group 3 but did not differ significantly between diplotype groups. In sum, the influence of SLCO1B1*15 and *17 haplotypes on pravastatin pharmacokinetics was maintained in the presence of darunavir/ritonavir. Because OATP1B1 inhibition would be expected to be greater in carriers of normal or high-functioning SLCO1B1 haplotypes, these findings suggest that darunavir/ritonavir is not a potent inhibitor of OATP1B1-mediated pravastatin transport in vivo.
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Evaluation of perceived threat differences posed by filovirus variants.
Biosecur Bioterror
PUBLISHED: 11-09-2011
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In the United States, filoviruses (ebolaviruses and marburgviruses) are listed as National Institute of Allergy and Infectious Diseases (NIAID) Category A Priority Pathogens, Select Agents, and Centers for Disease Control and Prevention (CDC) Category A Bioterrorism Agents. In recent months, U.S. biodefense professionals and policy experts have initiated discussions on how to optimize filovirus research in regard to medical countermeasure (ie, diagnostics, antiviral, and vaccine) development. Standardized procedures and reagents could accelerate the independent verification of research results across government agencies and establish baselines for the development of animal models acceptable to regulatory entities, such as the Food and Drug Administration (FDA), while being fiscally responsible. At the root of standardization lies the question of which filovirus strains, variants, or isolates ought to be the prototypes for product development, evaluation, and validation. Here we discuss a rationale for their selection. We conclude that, based on currently available data, filovirus biodefense research ought to focus on the classical taxonomic filovirus prototypes: Marburg virus Musoke in the case of marburgviruses and Ebola virus Mayinga in the case of Zaire ebolaviruses. Arguments have been made in various committees in favor of other variants, such as Marburg virus Angola, Ci67 or Popp, or Ebola virus Kikwit, but these rationales seem to be largely based on anecdotal or unpublished and unverified data, or they may reflect a lack of awareness of important facts about the variants isolation history and genomic properties.
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Evaluation of monkeypox disease progression by molecular imaging.
J. Infect. Dis.
PUBLISHED: 10-19-2011
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Infection of nonhuman primates (NHPs) with monkeypox virus (MPXV) is currently being developed as an animal model of variola infection in humans. We used positron emission tomography and computed tomography (PET/CT) to identify inflammatory patterns as predictors for the outcome of MPXV disease in NHPs. Two NHPs were sublethally inoculated by the intravenous (IV) or intrabronchial (IB) routes and imaged sequentially using fluorine-18 fluorodeoxyglucose ((18)FDG) uptake as a nonspecific marker of inflammation/immune activation. Inflammation was observed in the lungs of IB-infected NHPs, and bilobular involvement was associated with morbidity. Lymphadenopathy and immune activation in the axillary lymph nodes were evident in IV- and IB-infected NHPs. Interestingly, the surviving NHPs had significant (18)FDG uptake in the axillary lymph nodes at the time of MPXV challenge with no clinical signs of illness, suggesting an association between preexisting immune activation and survival. Molecular imaging identified patterns of inflammation/immune activation that may allow risk assessment of monkeypox disease.
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CONSORT 2010 explanation and elaboration: updated guidelines for reporting parallel group randomised trials.
Int J Surg
PUBLISHED: 10-12-2011
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Overwhelming evidence shows the quality of reporting of randomised controlled trials (RCTs) is not optimal. Without transparent reporting, readers cannot judge the reliability and validity of trial findings nor extract information for systematic reviews. Recent methodological analyses indicate that inadequate reporting and design are associated with biased estimates of treatment effects. Such systematic error is seriously damaging to RCTs, which are considered the gold standard for evaluating interventions because of their ability to minimise or avoid bias. A group of scientists and editors developed the CONSORT (Consolidated Standards of Reporting Trials) statement to improve the quality of reporting of RCTs. It was first published in 1996 and updated in 2001. The statement consists of a checklist and flow diagram that authors can use for reporting an RCT. Many leading medical journals and major international editorial groups have endorsed the CONSORT statement. The statement facilitates critical appraisal and interpretation of RCTs. During the 2001 CONSORT revision, it became clear that explanation and elaboration of the principles underlying the CONSORT statement would help investigators and others to write or appraise trial reports. A CONSORT explanation and elaboration article was published in 2001 alongside the 2001 version of the CONSORT statement. After an expert meeting in January 2007, the CONSORT statement has been further revised and is published as the CONSORT 2010 Statement. This update improves the wording and clarity of the previous checklist and incorporates recommendations related to topics that have only recently received recognition, such as selective outcome reporting bias. This explanatory and elaboration document-intended to enhance the use, understanding, and dissemination of the CONSORT statement-has also been extensively revised. It presents the meaning and rationale for each new and updated checklist item providing examples of good reporting and, where possible, references to relevant empirical studies. Several examples of flow diagrams are included. The CONSORT 2010 Statement, this revised explanatory and elaboration document, and the associated website (www.consort-statement.org) should be helpful resources to improve reporting of randomised trials.
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Natural history of breast cancers detected in the Swedish mammography screening programme: a cohort study.
Lancet Oncol.
PUBLISHED: 10-11-2011
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The natural history of screen-detected breast cancers is not well understood. A previous analysis of the incidence change during the introduction of the Norwegian screening programme in the late 1990s suggested that the natural history of many screen-detected invasive breast cancers is to regress spontaneously but the study was possibly confounded by use of hormone replacement therapy in the population. We did a similar analysis of data collected during an earlier period when few women were exposed to hormone replacement therapy.
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Intrabronchial inoculation of cynomolgus macaques with cowpox virus.
J. Gen. Virol.
PUBLISHED: 09-21-2011
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The public health threat of orthopoxviruses from bioterrorist attacks has prompted researchers to develop suitable animal models for increasing our understanding of viral pathogenesis and evaluation of medical countermeasures (MCMs) in compliance with the FDA Animal Efficacy Rule. We present an accessible intrabronchial cowpox virus (CPXV) model that can be evaluated under biosafety level-2 laboratory conditions. In this dose-ranging study, utilizing cynomolgus macaques, signs of typical orthopoxvirus disease were observed with the lymphoid organs, liver, skin (generally mild) and respiratory tract as target tissues. Clinical and histopathological evaluation suggests that intrabronchial CPXV recapitulated many of the features of monkeypox and variola virus, the causative agent of smallpox, infections in cynomolgus macaque models. These similarities suggest that CPXV infection in non-human primates should be pursued further as an alternative model of smallpox. Further development of the CPXV primate model, unimpeded by select agent and biocontainment restrictions, should facilitate the development of MCMs for smallpox.
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Oligomeric state of the oxalate transporter, OxlT.
Biochemistry
PUBLISHED: 09-08-2011
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OxlT, the oxalate transporter of Oxalobacter formigenes, was studied to determine its oligomeric state in solution and in the membrane. Three independent approaches were used. First, we used triple-detector (SEC-LS) size exclusion chromatography to analyze purified OxlT in detergent/lipid micelles. These measurements evaluate protein mass in a manner independent of contributions from detergent and lipid; such work shows an average OxlT mass near 47 kDa for detergent-solubilized material, consistent with that expected for monomeric OxlT (46 kDa). A disulfide-linked OxlT mutant was used to verify that it was possible detect dimers under these conditions. A second approach used amino-reactive cross-linkers of varying spacer lengths to study OxlT in detergent/lipid micelles and in natural or artificial membranes, followed by analysis via sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These tests, performed under conditions where the presence of dimers can be documented for either of two known dimeric transporters (AdiC or TetL), indicate that OxlT exists as a monomer in the membrane and retains this status upon detergent solubilization. In a final test, we showed that reconstitution of OxlT into lipid vesicles at variable protein/lipid ratios has no effect on the specific activity of subsequent oxalate transport, as the OxlT content varies between 0.027 and 5.4 OxlT monomers/proteoliposome. We conclude that OxlT is a functional monomer in the membrane and in detergent/lipid micelles.
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The breast screening programme and misinforming the public.
J R Soc Med
PUBLISHED: 09-02-2011
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The information provided to the public by the NHS Breast Screening Programme has been criticized for lack of balance, omission of information on harms and substantially exaggerated estimates of benefit. These shortcomings have been particularly evident in the various invitation leaflets for breast screening and in the Programmes own 2008 Annual Review, which celebrated 20 years of screening. The debate on screening has been heated after new data published in the last two years questioned the benefit and documented substantial harm. We therefore analysed whether the recent debate and new pivotal data about breast screening has had any impact on the contents of the new 2010 leaflet and on the 2010 Annual Review. We conclude that spokespeople for the Programme have stuck to the beliefs about benefit that prevailed 25 years ago. Concerns about over-diagnosis have not been addressed either and official documents still downplay this most important harm of breast cancer screening.
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Multiplicity of data in trial reports and the reliability of meta-analyses: empirical study.
BMJ
PUBLISHED: 09-01-2011
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To examine the extent of multiplicity of data in trial reports and to assess the impact of multiplicity on meta-analysis results.
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Inhibition of cowpox virus and monkeypox virus infection by mitoxantrone.
Antiviral Res.
PUBLISHED: 08-21-2011
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Mitoxantrone, an FDA-approved therapeutic for the treatment of cancer and multiple sclerosis, was previously reported to exhibit antiviral activity against vaccinia virus. To determine whether this activity extends to other orthopoxviruses, mitoxantrone was tested against cowpox and monkeypox. Mitoxantrone demonstrated an EC(50) of 0.25 ?M against cowpox and 0.8 ?M against monkeypox. Intraperitoneal treatment of cowpox virus-challenged C57Bl/6 mice with 0.5 mg/kg mitoxantrone resulted in 25% survival and a significant increase in survival time. In an effort to improve its efficacy, mitoxantrone was tested for synergistic activity with cidofovir. In vitro tests demonstrated significant synergy between the two drugs against cowpox; however, no synergistic effect on animal survival or median time-to-death was seen in intranasally-infected BALB/c mice. Significantly fewer animals survived when treated with a combination of 0.5 mg/kg mitoxantrone and 100 mg/kg cidofovir than with 100 mg/kg cidofovir alone. This is, to our knowledge, the first report of limited anti-orthopoxvirus activity by mitoxantrone in an animal model.
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Inactivated or live-attenuated bivalent vaccines that confer protection against rabies and Ebola viruses.
J. Virol.
PUBLISHED: 08-17-2011
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The search for a safe and efficacious vaccine for Ebola virus continues, as no current vaccine candidate is nearing licensure. We have developed (i) replication-competent, (ii) replication-deficient, and (iii) chemically inactivated rabies virus (RABV) vaccines expressing Zaire Ebola virus (ZEBOV) glycoprotein (GP) by a reverse genetics system based on the SAD B19 RABV wildlife vaccine. ZEBOV GP is efficiently expressed by these vaccine candidates and is incorporated into virions. The vaccine candidates were avirulent after inoculation of adult mice, and viruses with a deletion in the RABV glycoprotein had greatly reduced neurovirulence after intracerebral inoculation in suckling mice. Immunization with live or inactivated RABV vaccines expressing ZEBOV GP induced humoral immunity against each virus and conferred protection from both lethal RABV and EBOV challenge in mice. The bivalent RABV/ZEBOV vaccines described here have several distinct advantages that may speed the development of inactivated vaccines for use in humans and potentially live or inactivated vaccines for use in nonhuman primates at risk of EBOV infection in endemic areas.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.