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Find video protocols related to scientific articles indexed in Pubmed.
Viral aetiology of central nervous system infections in adults admitted to a tertiary referral hospital in southern Vietnam over 12 years.
PLoS Negl Trop Dis
PUBLISHED: 08-28-2014
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Central nervous system (CNS) infections are important diseases in both children and adults worldwide. The spectrum of infections is broad, encompassing bacterial/aseptic meningitis and encephalitis. Viruses are regarded as the most common causes of encephalitis and aseptic meningitis. Better understanding of the viral causes of the diseases is of public health importance, in order to better inform immunization policy, and may influence clinical management.
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Evaluation of Intravenous Peramivir for Treatment of Influenza in Hospitalized Patients.
Clin. Infect. Dis.
PUBLISHED: 08-12-2014
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?Seasonal influenza causes >200 000 annual hospitalizations in the United States. Current antiviral treatment options are limited to oral or inhaled agents. There is an urgent unmet need for intravenous antiviral treatments.
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[Is enterovirus 71 vaccination also necessary in the Netherlands?].
Ned Tijdschr Geneeskd
PUBLISHED: 07-03-2014
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Enterovirus 71 (EV71) is an emerging infection, causing large outbreaks in Asia with high morbidity and mortality in children. New vaccines against EV71 have been developed and tested in China, leading to two recent publications on the efficacy of these vaccines in The New England Journal of Medicine. Although the results look promising, it is not expected that vaccination against EV71 will be introduced in Europe any time soon. Large outbreaks with high morbidity have not yet been observed in Europe, and the genotypes causing these outbreaks in Asia circulate only to a low extent in Europe. However, in the future this might change, and experience with EV71 vaccination as is now gained in China might be valuable.
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The Carriage Of Multiresistant Bacteria After Travel (COMBAT) prospective cohort study: methodology and design.
BMC Public Health
PUBLISHED: 04-03-2014
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Antimicrobial resistance (AMR) is one of the major threats to public health around the world. Besides the intense use and misuse of antimicrobial agents as the major force behind the increase in antimicrobial resistance, the exponential increase of international travel may also substantially contribute to the emergence and spread of AMR. However, knowledge on the extent to which international travel contributes to this is still limited. The Carriage Of Multiresistant Bacteria After Travel (COMBAT) study aims to 1. determine the acquisition rate of multiresistant Enterobacteriaceae during foreign travel 2. ascertain the duration of carriage of these micro-organisms 3. determine the transmission rate within households 4. identify risk factors for acquisition, persistence of carriage and transmission of multiresistant Enterobacteriaceae.
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Performance of Kiestra total laboratory automation combined with MS in clinical microbiology practice.
Ann Lab Med
PUBLISHED: 02-13-2014
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Microbiological laboratories seek technologically innovative solutions to cope with large numbers of samples and limited personnel and financial resources. One platform that has recently become available is the Kiestra Total Laboratory Automation (TLA) system (BD Kiestra B.V., the Netherlands). This fully automated sample processing system, equipped with digital imaging technology, allows superior detection of microbial growth. Combining this approach with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MS) (Bruker Daltonik, Germany) is expected to enable more rapid identification of pathogens.
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Pandemic H1N1 virus transmission and shedding dynamics in index case households of a prospective Vietnamese cohort.
J. Infect.
PUBLISHED: 01-21-2014
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Influenza household transmission studies are required to guide prevention strategies but most passively recruit index cases that seek healthcare. We investigated A(H1N1)pdm09 transmission in a household-based cohort during 2009.
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Limited geographic distribution of the novel cyclovirus CyCV-VN.
Sci Rep
PUBLISHED: 01-17-2014
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A novel cyclovirus, CyCV-VN, was recently identified in cerebrospinal fluid (CSF) from patients with central nervous system (CNS) infections in central and southern Vietnam. To explore the geographic distribution of this novel virus, more than 600?CSF specimens from patients with suspected CNS infections in northern Vietnam, Cambodia, Nepal and The Netherlands were screened for the presence of CyCV-VN but all were negative. Sequence comparison and phylogenetic analysis between CyCV-VN and another novel cyclovirus recently identified in CSF from Malawian patients indicated that these represent distinct cycloviral species, albeit phylogenetically closely related. The data suggest that CyCV-VN has a limited geographic distribution within southern and central Vietnam. Further research is needed to determine the global distribution and diversity of cycloviruses and importantly their possible association with human disease.
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Patient-based transcriptome-wide analysis identify interferon and ubiquination pathways as potential predictors of influenza a disease severity.
PLoS ONE
PUBLISHED: 01-01-2014
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The influenza A virus is an RNA virus that is responsible for seasonal epidemics worldwide with up to five million cases of severe illness and 500,000 deaths annually according to the World Health Organization estimates. The factors associated with severe diseases are not well defined, but more severe disease is more often seen among persons aged >65 years, infants, pregnant women, and individuals of any age with underlying health conditions.
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How integration of global omics-data could help preparing for pandemics - a scent of influenza.
Front Genet
PUBLISHED: 01-01-2014
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Pandemics caused by novel emerging or re-emerging infectious diseases could lead to high mortality and morbidity world-wide when left uncontrolled. In this perspective, we evaluate the possibility of integration of global omics-data in order to timely prepare for pandemics. Such an approach requires two major innovations. First, data that is obtained should be shared with the global community instantly. The strength of rapid integration of simple signals is exemplified by Google's(TM) Flu Trend, which could predict the incidence of influenza-like illness based on online search engine queries. Second, omics technologies need to be fast and high-throughput. We postulate that analysis of the exhaled breath would be a simple, rapid and non-invasive alternative. Breath contains hundreds of volatile organic compounds that are altered by infection and inflammation. The molecular fingerprint of breath (breathprint) can be obtained using an electronic nose, which relies on sensor technology. These breathprints can be stored in an online database (a "breathcloud") and coupled to clinical data. Comparison of the breathprint of a suspected subject to the breathcloud allows for a rapid decision on the presence or absence of a pathogen.
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Emergence of the Virulence-associated PB2 E627K Substitution in a Fatal Human Case of Highly Pathogenic Avian Influenza Virus A(H7N7) Infection Determined by Illumina Ultra-deep Sequencing.
J. Virol.
PUBLISHED: 11-20-2013
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Avian influenza viruses are capable of crossing the species barrier and infect humans. Although evidence of human-to-human transmission of avian influenza viruses to date is limited, evolution of variants towards more efficient human-to-human transmission could result in a new influenza virus pandemic. In both the avian influenza A(H5N1) and the recently emerging avian influenza A(H7N9) viruses, the PB2 E627K mutation appears of key importance for human adaptation. During a large influenza A(H7N7) outbreak in the Netherlands in 2003, the A(H7N7) virus isolated from a fatal human case contained the PB2 E627K mutation as well as a HA K416R mutation. In this study, we aimed to investigate whether these mutations occurred in the avian or the human host by Illumina ultra-deep sequencing of three previously uninvestigated clinical samples obtained from the fatal case. In addition, we investigated three chicken samples, two of which were obtained from the source farm. Results showed that the PB2 E627K mutation was not present in any of the chicken samples tested. Surprisingly, the avian samples were characterized by the presence of influenza defective RNA segments, suggestive for the synthesis of defective-interfering viruses during infection in poultry. In the human samples, the PB2 E627K mutation was identified with increasing frequency during infection. Our results strongly suggest that human adaptation marker PB2 E627K has emerged during virus infection of a single human host, emphasizing the importance of reducing human exposure to avian influenza viruses to reduce the likelihood of viral adaptation to humans.
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Subclinical avian influenza A(H5N1) virus infection in human, Vietnam.
Emerging Infect. Dis.
PUBLISHED: 09-20-2013
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Laboratory-confirmed cases of subclinical infection with avian influenza A(H5N1) virus in humans are rare, and the true number of these cases is unknown. We describe the identification of a laboratory-confirmed subclinical case in a woman during an influenza A(H5N1) contact investigation in northern Vietnam.
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Using routine diagnostic data as a method of surveillance of arboviral infection in travellers: A comparative analysis with a focus on dengue.
Travel Med Infect Dis
PUBLISHED: 06-25-2013
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In a large part of the developing world, limited infectious disease surveillance is performed. In laboratory information management systems data on diagnostic requests is available and may be amenable to trend analyses. We explored this potential, using DENV diagnostic requests as a model.
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Changes in the hemagglutinin of H5N1 viruses during human infection--influence on receptor binding.
Virology
PUBLISHED: 06-21-2013
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As avian influenza A(H5N1) viruses continue to circulate in Asia and Africa, global concerns of an imminent pandemic persist. Recent experimental studies suggest that efficient transmission between humans of current H5N1 viruses only requires a few genetic changes. An essential step is alteration of the virus hemagglutinin from preferential binding to avian receptors for the recognition of human receptors present in the upper airway. We have identified receptor-binding changes which emerged during H5N1 infection of humans, due to single amino acid substitutions, Ala134Val and Ile151Phe, in the hemagglutinin. Detailed biological, receptor-binding, and structural analyses revealed reduced binding of the mutated viruses to avian-like receptors, but without commensurate increased binding to the human-like receptors investigated, possibly reflecting a receptor-binding phenotype intermediate in adaptation to more human-like characteristics. These observations emphasize that evolution in nature of avian H5N1 viruses to efficient binding of human receptors is a complex multistep process.
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Identification of a new cyclovirus in cerebrospinal fluid of patients with acute central nervous system infections.
MBio
PUBLISHED: 06-20-2013
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Acute central nervous system (CNS) infections cause substantial morbidity and mortality, but the etiology remains unknown in a large proportion of cases. We identified and characterized the full genome of a novel cyclovirus (tentatively named cyclovirus-Vietnam [CyCV-VN]) in cerebrospinal fluid (CSF) specimens of two Vietnamese patients with CNS infections of unknown etiology. CyCV-VN was subsequently detected in 4% of 642 CSF specimens from Vietnamese patients with suspected CNS infections and none of 122 CSFs from patients with noninfectious neurological disorders. Detection rates were similar in patients with CNS infections of unknown etiology and those in whom other pathogens were detected. A similar detection rate in feces from healthy children suggested food-borne or orofecal transmission routes, while high detection rates in feces from pigs and poultry (average, 58%) suggested the existence of animal reservoirs for such transmission. Further research is needed to address the epidemiology and pathogenicity of this novel, potentially zoonotic virus.
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Febrile neutropenia: significance of elaborated screening for respiratory viruses, and the comparison of different sampling methods, in neutropenic patients with hematological malignancies.
Virol. J.
PUBLISHED: 05-23-2013
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During febrile neutropenia in only 30 to 60 percent an infectious agent is identified. This diagnostic gap could hypothetically be reduced with the broad implementation of molecular detection techniques like PCR, which has revolutionized the detection of infectious diseases during the last two decades.
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2D and 3D self-assembling nanofiber hydrogels for cardiomyocyte culture.
Biomed Res Int
PUBLISHED: 04-11-2013
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Collagen is a widely used biomaterial in cardiac tissue engineering studies. However, as a natural material, it suffers from variability between batches that can complicate the standardization of culture conditions. In contrast, synthetic materials are modifiable, have well-defined structures and more homogeneous batches can be produced. In this study, several collagen-like synthetic self-assembling nanofiber hydrogels were examined for their suitability for cardiomyocyte culture in 2D and 3D. Six different nanofiber coatings were used in the 2D format with neonatal rat cardiomyocytes (NRCs) and human embryonic stem-cell-derived cardiomyocytes (hESC-CMs). The viability, growth, and functionality of the 2D-cultured cardiomyocytes were evaluated. The best-performing nanofiber coatings were selected for 3D experiments. Hydrophilic pH-sensitive nanofiber hydrogel coassembled with hyaluronic acid performed best with both NRCs and hESC-CMs. Hydrophilic non-pH-sensitive nanofiber hydrogels supported the growth of NRCs; however, their ability to promote attachment and growth of hESC-CMs was limited. NRCs also grew on hydrophobic nanofiber hydrogels; however, the cell-supporting capacity of these hydrogels was inferior to that of the hydrophilic hydrogel materials. This is the first study demonstrating that hydrophilic self-assembling nanofiber hydrogels support the culture of both NRCs and hESC-CMs, which suggests that these biomaterials hold promise for cardiac tissue engineering.
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Childrens perspectives on cyberbullying: insights based on participatory research.
Cyberpsychol Behav Soc Netw
PUBLISHED: 02-25-2013
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Cyberbullying is an emerging problem among youngsters. Although the current body of knowledge about cyberbullying is expanding rapidly, it lacks a more in-depth research approach honoring adolescents perspectives on the problem. Moreover, very few studies have focused on cyberbullying among elementary school children. The purpose of this study therefore, was to explore childrens perspectives on the problem of cyberbullying. A participatory research design was used in which 28 children (aged 11-12 from four elementary schools) actively participated for 6 weeks in weekly scheduled group sessions. In these sessions, different aspects of cyberbullying were discussed using various enabling techniques. Between sessions, the children were given preparation assignments. The research revealed several ambiguities that should be addressed in interventions against cyberbullying. First, it appears difficult for all parties involved to distinguish cyberbullying from innocent pranks. Frequency and intention are key variables, but these are ambiguous in the context of cyberbullying. Second, cyberbullies may have very different motives, not all of which have to do with their relationship with the victim. Third, the expectations children have of the way their parents or teachers will react to incidents of cyberbullying are an obstacle for seeking help. Children are particularly afraid of overreaction and the subsequent loss of their Internet privileges. These results confirm earlier insights from research on cyberbullying, and examine the ambiguities in more detail. In addition, the research demonstrates the usefulness of participatory research to investigate cyberbullying among younger children and demonstrates that the research led to mutual learning.
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One more beer? Serving alcohol to pseudo-intoxicated guests in bars.
Alcohol. Clin. Exp. Res.
PUBLISHED: 02-21-2013
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Consuming large quantities of alcohol might result in negative consequences for both individual drinkers (alcohol dependency and addiction) and society (violence, traffic crashes). In order to decrease the prevalence of alcohol abuse, many countries have adopted regulations prohibiting the catering industry to serve alcohol to intoxicated guests. This article investigated compliance with these regulations in the Netherlands.
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Autologous antibody capture to enrich immunogenic viruses for viral discovery.
PLoS ONE
PUBLISHED: 01-01-2013
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Discovery of new viruses has been boosted by novel deep sequencing technologies. Currently, many viruses can be identified by sequencing without knowledge of the pathogenicity of the virus. However, attributing the presence of a virus in patient material to a disease in the patient can be a challenge. One approach to meet this challenge is identification of viral sequences based on enrichment by autologous patient antibody capture. This method facilitates identification of viruses that have provoked an immune response within the patient and may increase the sensitivity of the current virus discovery techniques. To demonstrate the utility of this method, virus discovery deep sequencing (VIDISCA-454) was performed on clinical samples from 19 patients: 13 with a known respiratory viral infection and 6 with a known gastrointestinal viral infection. Patient sera was collected from one to several months after the acute infection phase. Input and antibody capture material was sequenced and enrichment was assessed. In 18 of the 19 patients, viral reads from immunogenic viruses were enriched by antibody capture (ranging between 1.5x to 343x in respiratory material, and 1.4x to 53x in stool). Enriched reads were also determined in an identity independent manner by using a novel algorithm Xcompare. In 16 of the 19 patients, 21% to 100% of the enriched reads were derived from infecting viruses. In conclusion, the technique provides a novel approach to specifically identify immunogenic viral sequences among the bulk of sequences which are usually encountered during virus discovery metagenomics.
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Low primary and secondary HIV drug-resistance after 12 months of antiretroviral therapy in human immune-deficiency virus type 1 (HIV-1)-infected individuals from Kigali, Rwanda.
PLoS ONE
PUBLISHED: 01-01-2013
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Treatment outcomes of HIV patients receiving antiretroviral therapy (ART) in Rwanda are scarcely documented. HIV viral load (VL) and HIV drug-resistance (HIVDR) outcomes at month 12 were determined in a prospective cohort study of antiretroviral-naïve HIV patients initiating first-line therapy in Kigali. Treatment response was monitored clinically and by regular CD4 counts and targeted HIV viral load (VL) to confirm drug failure. VL measurements and HIVDR genotyping were performed retrospectively on baseline and month 12 samples. One hundred and fifty-eight participants who completed their month 12 follow-up visit had VL data available at month 12. Most of them (88%) were virologically suppressed (VL?1000 copies/mL) but 18 had virological failure (11%), which is in the range of WHO-suggested targets for HIVDR prevention. If only CD4 criteria had been used to classify treatment response, 26% of the participants would have been misclassified as treatment failure. Pre-therapy HIVDR was documented in 4 of 109 participants (3.6%) with an HIVDR genotyping results at baseline. Eight of 12 participants (66.7%) with virological failure and HIVDR genotyping results at month 12 were found to harbor mutation(s), mostly NNRTI resistance mutations, whereas 4 patients had no HIVDR mutations. Almost half (44%) of the participants initiated ART at CD4 count ?200 cell/µl and severe CD4 depletion at baseline (<50 cells/µl) was associated with virological treatment failure (p?=?0.008). Although the findings may not be generalizable to all HIV patients in Rwanda, our data suggest that first-line ART regimen changes are currently not warranted. However, the accumulation of acquired HIVDR mutations in some participants underscores the need to reinforce HIVDR prevention strategies, such as increasing the availability and appropriate use of VL testing to monitor ART response, ensuring high quality adherence counseling, and promoting earlier identification of HIV patients and enrollment into HIV care and treatment programs.
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Virulence attenuation during an influenza A/H5N1 pandemic.
Philos. Trans. R. Soc. Lond., B, Biol. Sci.
PUBLISHED: 01-01-2013
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More than 15 years after the first human cases of influenza A/H5N1 in Hong Kong, the world remains at risk for an H5N1 pandemic. Preparedness activities have focused on antiviral stockpiling and distribution, development of a human H5N1 vaccine, operationalizing screening and social distancing policies, and other non-pharmaceutical interventions. The planning of these interventions has been done in an attempt to lessen the cumulative mortality resulting from a hypothetical H5N1 pandemic. In this theoretical study, we consider the natural limitations on an H5N1 pandemics mortality imposed by the virus epidemiological-evolutionary constraints. Evolutionary theory dictates that pathogens should evolve to be relatively benign, depending on the magnitude of the correlation between a pathogens virulence and its transmissibility. Because the case fatality of H5N1 infections in humans is currently 60 per cent, it is doubtful that the current viruses are close to their evolutionary optimum for transmission among humans. To describe the dynamics of virulence evolution during an H5N1 pandemic, we build a mathematical model based on the patterns of clinical progression in past H5N1 cases. Using both a deterministic model and a stochastic individual-based simulation, we describe (i) the drivers of evolutionary dynamics during an H5N1 pandemic, (ii) the range of case fatalities for which H5N1 viruses can successfully cause outbreaks in humans, and (iii) the effects of different kinds of social distancing on virulence evolution. We discuss two main epidemiological-evolutionary features of this system (i) the delaying or slowing of an epidemic which results in a majority of hosts experiencing an attenuated virulence phenotype and (ii) the strong evolutionary pressure for lower virulence experienced by the virus during a period of intense social distancing.
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Viral population analysis and minority-variant detection using short read next-generation sequencing.
Philos. Trans. R. Soc. Lond., B, Biol. Sci.
PUBLISHED: 01-01-2013
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RNA viruses within infected individuals exist as a population of evolutionary-related variants. Owing to evolutionary change affecting the constitution of this population, the frequency and/or occurrence of individual viral variants can show marked or subtle fluctuations. Since the development of massively parallel sequencing platforms, such viral populations can now be investigated to unprecedented resolution. A critical problem with such analyses is the presence of sequencing-related errors that obscure the identification of true biological variants present at low frequency. Here, we report the development and assessment of the Quality Assessment of Short Read (QUASR) Pipeline (http://sourceforge.net/projects/quasr) specific for virus genome short read analysis that minimizes sequencing errors from multiple deep-sequencing platforms, and enables post-mapping analysis of the minority variants within the viral population. QUASR significantly reduces the error-related noise in deep-sequencing datasets, resulting in increased mapping accuracy and reduction of erroneous mutations. Using QUASR, we have determined influenza virus genome dynamics in sequential samples from an in vitro evolution of 2009 pandemic H1N1 (A/H1N1/09) influenza from samples sequenced on both the Roche 454 GSFLX and Illumina GAIIx platforms. Importantly, concordance between the 454 and Illumina sequencing allowed unambiguous minority-variant detection and accurate determination of virus population turnover in vitro.
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The ecology, genetic diversity, and phylogeny of Huaiyangshan virus in China.
J. Virol.
PUBLISHED: 12-21-2011
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Surveys were carried out to better understand the tick vector ecology and genetic diversity of Huaiyangshan virus (HYSV) in both regions of endemicity and regions of nonendemicity. Haemaphysalis longicornis ticks were dominant in regions of endemicity, while Rhipicephalus microplus is more abundant in regions of nonendemicity. HYSV RNA was found in human and both tick species, with greater prevalence in H. longicornis and lesser prevalence in R. microplus. Phylogenetic analyses indicate that HYSV is a novel species of the genus Phlebovirus.
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Hemorrhagic fever caused by a novel Bunyavirus in China: pathogenesis and correlates of fatal outcome.
Clin. Infect. Dis.
PUBLISHED: 12-05-2011
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?Hemorrhagic fever-like illness caused by a novel Bunyavirus, Huaiyangshan virus (HYSV, also known as Severe Fever with Thrombocytopenia virus [SFTSV] and Fever, Thrombocytopenia and Leukopenia Syndrome [FTLS]), has recently been described in China.
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High-resolution analysis of intrahost genetic diversity in dengue virus serotype 1 infection identifies mixed infections.
J. Virol.
PUBLISHED: 11-16-2011
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Little is known about the rate at which genetic variation is generated within intrahost populations of dengue virus (DENV) and what implications this diversity has for dengue pathogenesis, disease severity, and host immunity. Previous studies of intrahost DENV variation have used a low frequency of sampling and/or experimental methods that do not fully account for errors generated through amplification and sequencing of viral RNAs. We investigated the extent and pattern of genetic diversity in sequence data in domain III (DIII) of the envelope (E) gene in serial plasma samples (n = 49) taken from 17 patients infected with DENV type 1 (DENV-1), totaling some 8,458 clones. Statistically rigorous approaches were employed to account for artifactual variants resulting from amplification and sequencing, which we suggest have played a major role in previous studies of intrahost genetic variation. Accordingly, nucleotide sequence diversities of viral populations were very low, with conservative estimates of the average levels of genetic diversity ranging from 0 to 0.0013. Despite such sequence conservation, we observed clear evidence for mixed infection, with the presence of multiple phylogenetically distinct lineages present within the same host, while the presence of stop codon mutations in some samples suggests the action of complementation. In contrast to some previous studies we observed no relationship between the extent and pattern of DENV-1 genetic diversity and disease severity, immune status, or level of viremia.
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Improving shop floor compliance with age restrictions for alcohol sales: effectiveness of a feedback letter intervention.
Eur J Public Health
PUBLISHED: 11-10-2011
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In this study, we investigated the effects and handling of an intervention to increase compliance with age limits regarding alcohol sales. The intervention tested in this field experiment was a feedback letter sent to alcohol outlets about their individual compliance results based on a mystery shopping study.
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Frequent detection of respiratory viruses without symptoms: toward defining clinically relevant cutoff values.
J. Clin. Microbiol.
PUBLISHED: 05-04-2011
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Highly sensitive techniques, such as PCR, have greatly improved the detection of respiratory viruses. However, the sensitivity of PCR tests also complicates clinical interpretation, as the presence of small amounts of viral targets may not necessarily have clinical relevance. We performed a prospective case-control study in asymptomatic and symptomatic young children. PCR detection of 14 respiratory viruses was performed in nasal washes, and results were quantified in copies per milliliter. A total of 141 cases and 157 controls were included. In 72% of the cases and 28% of the controls, at least one virus was identified. When stratified for age, at least one virus was identified in 47% of the controls younger than 1 year old. Rhinovirus (RV) was frequently detected in both symptomatic and asymptomatic individuals. Receiver operating characteristic analysis for quantitative rhinovirus detection showed that cutoff values for clinical relevance are feasible for RV. In contrast to rhinovirus, respiratory syncytial virus (RSV) was rarely detected in controls, suggesting that a positive RSV test result is almost always of clinical relevance, independent of viral quantity. In conclusion, our study shows that asymptomatic carriage of a respiratory virus occurs frequently in young children. However, significant differences in the amount of virus present were observed between cases and controls. This suggests that defining cutoff levels should be feasible and represents the next necessary step for diagnosing viral respiratory infections using molecular tests.
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Effects of a national information campaign on compliance with age restrictions for alcohol sales.
J Adolesc Health
PUBLISHED: 04-12-2011
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To investigate the effect of a national information campaign, introduced by the Dutch Food Retail Organization, named "Under 20? Show Your ID!," on compliance with age restrictions on alcohol sales. The compliance level after the campaign was compared with a baseline compliance, that we calculated based on 458 preintervention compliance measurements.
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Hemorrhagic fever caused by a novel tick-borne Bunyavirus in Huaiyangshan, China.
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 04-05-2011
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From April to July in 2009 and 2010, unexplained severe hemorrhagic fever-like illnesses occurred in farmers from the Huaiyangshan mountains range.
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Making sense of alcohol experiences: young adolescents accounts of alcohol-related critical incidents.
Addict Behav
PUBLISHED: 03-29-2011
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This study explores how alcohol use is incorporated in the lives of young adolescents in the Netherlands. To this end, critical incidents involving alcohol use situations are analyzed. Special attention is paid to the consequences associated with alcohol use, the role of the parents, and the way adolescents evaluate incidents and link them to behavioral intentions.
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Random PCR and ultracentrifugation increases sensitivity and throughput of VIDISCA for screening of pathogens in clinical specimens.
J Infect Dev Ctries
PUBLISHED: 03-11-2011
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Virus discovery based on cDNA-AFLP (VIDISCA) is a sequence-independent virus discovery method that was recently developed and successfully used to characterize unknown viruses in cell cultures. Its applicability, however, is limited by its low sensitivity.
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Development and evaluation of a four-tube real time multiplex PCR assay covering fourteen respiratory viruses, and comparison to its corresponding single target counterparts.
J. Clin. Virol.
PUBLISHED: 02-28-2011
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Multiplex real time PCR is increasingly used to diagnose respiratory viruses and has shown to be superior to traditional methods, like culture and antigen detection. However, comprehensive data on sensitivity, specificity and performance of the multiplex PCR compared to the single target PCRs is limited for most published respiratory multiplex real time PCR assays.
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Viral etiologies of acute respiratory infections among hospitalized Vietnamese children in Ho Chi Minh City, 2004-2008.
PLoS ONE
PUBLISHED: 02-27-2011
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The dominant viral etiologies responsible for acute respiratory infections (ARIs) are poorly understood, particularly among hospitalized children in resource-limited tropical countries where morbidity and mortality caused by ARIs are highest. Improved etiological insight is needed to improve clinical management and prevention.
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Taming membranes: functional immobilization of biological membranes in hydrogels.
PLoS ONE
PUBLISHED: 02-16-2011
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Single molecule studies on membrane proteins embedded in their native environment are hampered by the intrinsic difficulty of immobilizing elastic and sensitive biological membranes without interfering with protein activity. Here, we present hydrogels composed of nano-scaled fibers as a generally applicable tool to immobilize biological membrane vesicles of various size and lipid composition. Importantly, membrane proteins immobilized in the hydrogel as well as soluble proteins are fully active. The triggered opening of the mechanosensitive channel of large conductance (MscL) reconstituted in giant unilamellar vesicles (GUVs) was followed in time on single GUVs. Thus, kinetic studies of vectorial transport processes across biological membranes can be assessed on single, hydrogel immobilized, GUVs. Furthermore, protein translocation activity by the membrane embedded protein conducting channel of bacteria, SecYEG, in association with the soluble motor protein SecA was quantitatively assessed in bulk and at the single vesicle level in the hydrogel. This technique provides a new way to investigate membrane proteins in their native environment at the single molecule level by means of fluorescence microscopy.
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A sensitive real-time PCR for detection and subgrouping of human respiratory syncytial virus.
J. Virol. Methods
PUBLISHED: 01-07-2011
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Improved diagnostic tools for rapid detection, quantitation, and subgrouping of human respiratory syncytial virus (RSV) are needed to aid the development and evaluation of novel intervention strategies. A quantitative real-time RT-PCR using specific locked nucleic acid (LNA) probes was developed to identify RSV and to distinguish RSV subgroups A and B (RSV LNA assay). RSV subgroup diversity and the relationship between viral load and disease severity in confirmed RSV infections were also explored. 264 archived respiratory specimens from pediatric patients were tested in parallel using the commercial multiplex Seeplex™ RV detection kit (Seegene) and the novel RSV LNA assay. The LNA assay demonstrated a significantly higher sensitivity than Seeplex, improving overall detection rates from 24% (64/264) to 32% (84/264). Detection limits of 9.0×10(1) and 6.0×10(2)copies/mL were observed for RSV A and B, respectively. RSV A was detected in 53/84 (63%) cases, and 31/84 (37%) were positive for RSV B. This novel method offers a rapid, quantitative, highly specific and sensitive approach to laboratory diagnosis of RSV.
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Viral etiology of encephalitis in children in southern Vietnam: results of a one-year prospective descriptive study.
PLoS Negl Trop Dis
PUBLISHED: 05-19-2010
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Acute encephalitis is an important and severe disease in children in Vietnam. However, little is known about the etiology while such knowledge is essential for optimal prevention and treatment. To identify viral causes of encephalitis, in 2004 we conducted a one-year descriptive study at Childrens Hospital Number One, a referral hospital for children in southern Vietnam including Ho Chi Minh City.
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End points for testing influenza antiviral treatments for patients at high risk of severe and life-threatening disease.
J. Infect. Dis.
PUBLISHED: 04-29-2010
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Influenza infection results in substantial morbidity and mortality in hospitalized patients, including those who are immunocompromised or pregnant. Antiviral therapy likely provides considerable benefit to these patients, but few studies have been successfully conducted in these high-risk populations, and no drugs are specifically licensed for treating these subgroups. One of the key challenges facing novel antiviral drug development for influenza is determining the appropriate efficacy end points that would enable rapid regulatory approval for drug use in seriously ill patients, for whom risk-benefit assessments differ from those with uncomplicated illness. All available antiviral drugs currently affect viral replication, and respiratory tract viral titers correlate with both symptoms and measures of host inflammatory responses, including cytokine and chemokine expression that are likely responsible for many of the clinical symptoms. Consequently, we outline the evidence to support the use of primary virological end points in studies of antiviral agents involving patients who are hospitalized with severe influenza or those who are at high risk of severe and life-threatening disease.
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Nanowires formed by the co-assembly of a negatively charged low-molecular weight gelator and a zwitterionic polythiophene.
Chemphyschem
PUBLISHED: 04-09-2010
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Conjugated organic nanowires have been prepared by co-assembling a carboxylate containing low-molecular weight gelator (LMWG) and an amino acid substituted polythiophene derivative (PTT). Upon introducing the zwitterionic polyelectrolyte PTT to a basic molecular solution of the organogelator, the negative charges on the LMWG are compensated by the positive charges of the PTT. As a result, nanowires form through co-assembly. These nanowires are visualized by both transmission electron microscopy (TEM) and atomic force microscopy (AFM). Depending on the concentration and ratio of the components these nanowires can be micrometers long. These measurements further suggest that the aggregates adopt a helical conformation. The morphology of these nanowires are studied with fluorescent confocal laser scanning microscopy (CLSM). The interactions between LMWG and PTT are characterized by steady-state and time-resolved fluorescence spectroscopy studies. The steady-state spectra indicate that the backbone of the PTT adopts a more planar and more aggregated conformation when interacting with LMWG. The time- resolved fluorescence decay studies confirm this interpretation.
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Guidelines for identifying homologous recombination events in influenza A virus.
PLoS ONE
PUBLISHED: 03-10-2010
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The rapid evolution of influenza viruses occurs both clonally and non-clonally through a variety of genetic mechanisms and selection pressures. The non-clonal evolution of influenza viruses comprises relatively frequent reassortment among gene segments and a more rarely reported process of non-homologous RNA recombination. Homologous RNA recombination within segments has been proposed as a third such mechanism, but to date the evidence for the existence of this process among influenza viruses has been both weak and controversial. As homologous recombination has not yet been demonstrated in the laboratory, supporting evidence, if it exists, may come primarily from patterns of phylogenetic incongruence observed in gene sequence data. Here, we review the necessary criteria related to laboratory procedures and sample handling, bioinformatic analysis, and the known ecology and evolution of influenza viruses that need to be met in order to confirm that a homologous recombination event occurred in the history of a set of sequences. To determine if these criteria have an effect on recombination analysis, we gathered 8307 publicly available full-length sequences of influenza A segments and divided them into those that were sequenced via the National Institutes of Health Influenza Genome Sequencing Project (IGSP) and those that were not. As sample handling and sequencing are executed to a very high standard in the IGSP, these sequences should be less likely to be exposed to contamination by other samples or by laboratory strains, and thus should not exhibit laboratory-generated signals of homologous recombination. Our analysis shows that the IGSP data set contains only two phylogenetically-supported single recombinant sequences and no recombinant clades. In marked contrast, the non-IGSP data show a very large amount of potential recombination. We conclude that the presence of false positive signals in the non-IGSP data is more likely than false negatives in the IGSP data, and that given the evidence to date, homologous recombination seems to play little or no role in the evolution of influenza A viruses.
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Kinetics of neutralizing antibodies in patients naturally infected by H5N1 virus.
PLoS ONE
PUBLISHED: 03-01-2010
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Little is known about the kinetics of anti-H5 neutralizing antibodies in naturally H5N1-infected patients with severe clinical illness or asymptomatic infection.
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A real-time RT-PCR for detection of clade 1 and 2 H5N1 influenza A virus using locked nucleic acid (LNA) TaqMan probes.
Virol. J.
PUBLISHED: 02-22-2010
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The emergence and co-circulation of two different clades (clade 1 and 2) of H5N1 influenza viruses in Vietnam necessitates the availability of a diagnostic assay that can detect both variants.
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Triple combination of amantadine, ribavirin, and oseltamivir is highly active and synergistic against drug resistant influenza virus strains in vitro.
PLoS ONE
PUBLISHED: 02-03-2010
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The rapid emergence and subsequent spread of the novel 2009 Influenza A/H1N1 virus (2009 H1N1) has prompted the World Health Organization to declare the first pandemic of the 21st century, highlighting the threat of influenza to public health and healthcare systems. Widespread resistance to both classes of influenza antivirals (adamantanes and neuraminidase inhibitors) occurs in both pandemic and seasonal viruses, rendering these drugs to be of marginal utility in the treatment modality. Worldwide, virtually all 2009 H1N1 and seasonal H3N2 strains are resistant to the adamantanes (rimantadine and amantadine), and the majority of seasonal H1N1 strains are resistant to oseltamivir, the most widely prescribed neuraminidase inhibitor (NAI). To address the need for more effective therapy, we evaluated the in vitro activity of a triple combination antiviral drug (TCAD) regimen composed of drugs with different mechanisms of action against drug-resistant seasonal and 2009 H1N1 influenza viruses. Amantadine, ribavirin, and oseltamivir, alone and in combination, were tested against amantadine- and oseltamivir-resistant influenza A viruses using an in vitro infection model in MDCK cells. Our data show that the triple combination was highly synergistic against drug-resistant viruses, and the synergy of the triple combination was significantly greater than the synergy of any double combination tested (P<0.05), including the combination of two NAIs. Surprisingly, amantadine and oseltamivir contributed to the antiviral activity of the TCAD regimen against amantadine- and oseltamivir-resistant viruses, respectively, at concentrations where they had no activity as single agents, and at concentrations that were clinically achievable. Our data demonstrate that the TCAD regimen composed of amantadine, ribavirin, and oseltamivir is highly synergistic against resistant viruses, including 2009 H1N1. The TCAD regimen overcomes baseline drug resistance to both classes of approved influenza antivirals, and thus may represent a highly active antiviral therapy for seasonal and pandemic influenza.
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Determinants of parental support for governmental alcohol control policies.
Health Policy
PUBLISHED: 01-12-2010
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To explore determinants that predict parental support for governmental alcohol control policies in the Netherlands.
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Clinical, epidemiological and virological features of Dengue virus infections in Vietnamese patients presenting to primary care facilities with acute undifferentiated fever.
J. Infect.
PUBLISHED: 01-08-2010
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To explore clinical and virological characteristics and describe the epidemiology of dengue in patients who presented with acute undifferentiated fever (AUF) at primary health centers (PHC) in Binh Thuan Province, Vietnam.
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[Combating the new influenza A (H1N1) virus. I. Overview of the relevant virological aspects].
Ned Tijdschr Geneeskd
PUBLISHED: 09-30-2009
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In April 2009 a new influenza virus was discovered, which spread from Mexico to the rest of the world. The new influenza A (H1N1) virus is genetically related to swine flu viruses, and differs substantially from circulating human influenza viruses. It is able to spread from person to person. Because it is a completely new virus, there is probably little immunity in the population. The course of the infection is relatively mild, but the virus will mutate and it is not yet certain whether this will affect severity of the influenza. General practitioners have an important role in surveillance and treatment. The Community Health Services must be notified of any patients who are suspected of having the new influenza. Hygiene measures and administration of antiviral drugs to patients and their contacts may slow the spread. A delay in large-scale spread in the Netherlands allows time for the development of vaccines.
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Prevalence of antibodies against avian influenza A (H5N1) virus among Cullers and poultry workers in Ho Chi Minh City, 2005.
PLoS ONE
PUBLISHED: 08-06-2009
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Between 2003 and 2005, highly pathogenic avian influenza A (H5N1) viruses caused large scale outbreaks in poultry in the Ho Chi Minh City area in Vietnam. We studied the prevalence of antibodies against H5N1 in poultry workers and cullers who were active in the program in Ho Chi Minh City in 2004 and 2005.
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Theres alcohol in my soap: portrayal and effects of alcohol use in a popular television series.
Health Educ Res
PUBLISHED: 07-15-2009
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Two studies are reported addressing the media influences on adolescents alcohol-related attitudes and behaviours. A content analysis was conducted to investigate the prevalence of alcohol portrayal in a Dutch soap series. The coding scheme covered the alcohol consumption per soap character, drinking situations and drinking times. Inter-coder reliability was satisfactory. The results showed that alcohol portrayal was prominent and that many instances of alcohol use reflected undesirable behaviours. To assess the influence of such alcohol cues on adolescents, a 2x2 experiment was conducted focusing on the separate and combined effects of alcohol portrayal in the soap series and surrounding alcohol commercials. Whereas the alcohol commercials had the expected effects on adolescents attitudes, the alcohol-related soap content only appeared to have unexpected effects. Adolescents who were exposed to the alcohol portrayal in the soap series had a less positive attitude towards alcohol and lower drinking intentions. Implications of these findings for health policy and future research are discussed.
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Optimization and evaluation of an influenza A (H5) pseudotyped lentiviral particle-based serological assay.
J. Clin. Virol.
PUBLISHED: 06-03-2009
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Novel serological methods provide alternative options for sero-diagnosis, sero-epidemiology and for determining evidence of naturally acquired or vaccine induced immunity. Micro-neutralization tests are currently the gold standard for serological studies of highly pathogenic avian influenza in mammalian species but require handling live virus in a biosafety level (BSL) 3 environment. We previously reported the use of H5 pseudotyped lentiviral particles (H5pp) as an alternative to micro-neutralization tests in a BSL-2 setting (Nefkens et al., 2007).
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Shop floor compliance with age restrictions for tobacco sales: remote versus in-store age verification.
J Adolesc Health
PUBLISHED: 03-30-2009
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To compare traditional in-store age verification with a newly developed remote age verification system, 100 cigarette purchase attempts were made by 15-year-old "mystery shoppers." The remote system led to a strong increase in compliance (96% vs. 12%), reflecting more identification requests and more sale refusals when adolescents showed their identification cards.
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Combination therapy with amantadine, oseltamivir and ribavirin for influenza A infection: safety and pharmacokinetics.
Antivir. Ther. (Lond.)
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Antiviral resistance among influenza A viruses is associated with high morbidity and mortality in immunocompromised hosts. However, treatment strategies for drug-resistant influenza A are not established. A triple-combination antiviral drug (TCAD) regimen consisting of amantadine (AMT), oseltamivir (OSL) and ribavirin (RBV) demonstrated good efficacy in an animal model.
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The co-selection of fluoroquinolone resistance genes in the gut flora of Vietnamese children.
PLoS ONE
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Antimicrobial consumption is one of the major contributing factors facilitating the development and maintenance of bacteria exhibiting antimicrobial resistance. Plasmid-mediated quinolone resistance (PMQR) genes, such as the qnr family, can be horizontally transferred and contribute to reduced susceptibility to fluoroquinolones. We performed an observational study, investigating the copy number of PMQR after antimicrobial therapy. We enrolled 300 children resident in Ho Chi Minh City receiving antimicrobial therapy for acute respiratory tract infections (ARIs). Rectal swabs were taken on enrollment and seven days subsequently, counts for Enterobacteriaceae were performed and qnrA, qnrB and qnrS were quantified by using real-time PCR on metagenomic stool DNA. On enrollment, we found no association between age, gender or location of the participants and the prevalence of qnrA, qnrB or qnrS. Yet, all three loci demonstrated a proportional increase in the number of samples testing positive between day 0 and day 7. Furthermore, qnrB demonstrated a significant increase in copy number between paired samples (p<0.001; Wilcoxon rank-sum), associated with non-fluoroquinolone combination antimicrobial therapy. To our knowledge, this is the first study describing an association between the use of non-fluoroquinolone antimicrobials and the increasing relative prevalence and quantity of qnr genes. Our work outlines a potential mechanism for the selection and maintenance of PMQR genes and predicts a strong effect of co-selection of these resistance determinants through the use of unrelated and potentially unnecessary antimicrobial regimes.
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Molecular and phylogeographic analysis of human immuno-deficiency virus type 1 strains infecting treatment-naive patients from Kigali, Rwanda.
PLoS ONE
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This study aimed at describing the genetic subtype distribution of HIV-1 strains circulating in Kigali and their epidemiological link with the HIV-1 strains from the five countries surrounding Rwanda. One hundred and thirty eight pol (RT and PR) sequences from 116 chronically- and 22 recently-infected antiretroviral therapy (ART)-naïve patients from Kigali were generated and subjected to HIV drug resistance (HIV-DR), phylogenetic and recombinant analyses in connection with 366 reference pol sequences from Rwanda, Burundi, Kenya, Democratic Republic of Congo, Tanzania and Uganda (Los Alamos database). Among the Rwandan samples, subtype A1 predominated (71.7%), followed by A1/C recombinants (18.1%), subtype C (5.8%), subtype D (2.9%), one A1/D recombinant (0.7%) and one unknown subtype (0.7%). Thirteen unique and three multiple A1/C recombinant forms were identified. No evidence for direct transmission events was found within the Rwandan strains. Molecular characteristics of HIV-1 were similar between chronically and recently-infected individuals and were not significantly associated with demographic or social factors. Our report suggests that the HIV-1 epidemic in Kigali is characterized by the emergence of A1/C recombinants and is not phylogenetically connected with the HIV-1 epidemic in the five neighboring countries. The relatively low level of transmitted HIV-DR mutations (2.9%) reported here indicates the good performance of the ART programme in Rwanda. However, the importance of promoting couples counseling, testing and disclosure during HIV prevention strategies is highlighted.
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Specific cell tropism and neutralization of human parechovirus types 1 and 3: implications for pathogenesis and therapy development.
J. Gen. Virol.
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Human parechoviruses (HPeVs) are picornaviruses frequently infecting humans. While HPeV1 is associated with mild disease, HPeV3 is the cause of neonatal sepsis and meningitis. To test whether in vitro replication kinetics of HPeV1 and HPeV3 could be related to pathogenicity, HPeV1 and HPeV3 strains isolated from patients were cultured on cell lines of gastrointestinal, respiratory and neural origin, and replication kinetics were measured by real-time PCR. No relationship was found between clinical symptoms and in vitro replication of the HPeV1 strains. In contrast, the HPeV3 strains showed faster replication in neural cells and there was a relationship between higher in vitro replication kinetics and neuropathogenicity in the patient. Furthermore, HPeV1 could be neutralized efficiently by its specific antibody and by intravenous immunoglobulins (IVIG), while most HPeV3 strains could not be neutralized. In IVIG, very low neutralizing antibody (nAb) titres against HPeV3 were found. Additionally, very low nAb titres were observed in sera of two HPeV3-infected donors, while high nAb titres against HPeV1 could be detected. Our data suggest that the mild clinical course of HPeV1 infection is primarily influenced by strong nAb responses, while HPeV3 might be difficult to neutralize in vivo and therefore the course of infection will mainly be determined by in vivo cell tropism.
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Aetiologies of central nervous system infection in Viet Nam: a prospective provincial hospital-based descriptive surveillance study.
PLoS ONE
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Infectious diseases of the central nervous system (CNS) remain common and life-threatening, especially in developing countries. Knowledge of the aetiological agents responsible for these infections is essential to guide empiric therapy and develop a rational public health policy. To date most data has come from patients admitted to tertiary referral hospitals in Asia and there is limited aetiological data at the provincial hospital level where most patients are seen.
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HIV-1 drug resistance in antiretroviral-naive individuals with HIV-1-associated tuberculous meningitis initiating antiretroviral therapy in Vietnam.
Antivir. Ther. (Lond.)
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Access to antiretroviral therapy (ART) for HIV-infected individuals in Vietnam is rapidly expanding, but there are limited data on HIV drug resistance (HIVDR) to guide ART strategies.
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Course of pandemic influenza A(H1N1) 2009 virus infection in Dutch patients.
Influenza Other Respir Viruses
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The clinical dynamics of influenza A(H1N1) 2009 infections in 61 laboratory-confirmed Dutch cases were examined. An episode lasted a median of 7·5 days of which 2 days included fever. Respiratory symptoms resolved slowly, while systemic symptoms peaked early in the episode and disappeared quickly. Severity of each symptom was rated highest in the first few days. Furthermore, diarrhoea was negatively associated with viral load, but not with faecal excretion of influenza virus. Cases with comorbidities appeared to have higher viral loads than the cases without, suggesting a less effective immune response. These results complement information obtained through traditional surveillance.
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Clinical validation of a point-of-care multiplexed in vitro immunoassay using monoclonal antibodies (the MSD influenza test) in four hospitals in Vietnam.
J. Clin. Microbiol.
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Point-of-care (POC) diagnostic tests for influenza can considerably shorten the time to clinical decision making. An investigational POC test based on a multiplexed immunoassay was developed by Meso Scale Diagnostics, LLC (MSD), with the objective to make a more sensitive rapid test that can also subtype influenza A viruses (1977 H1, H3, and H5). Between February and November 2010, we conducted a prospective multicenter study at four hospitals in Vietnam and compared the performance of this test to that of the WHO/CDC real-time reverse transcriptase PCR (RT-PCR) on nasal and throat swab specimens from patients presenting with influenza-like illness. Five hundred sixty-three adults and children with a median age of 25 months were enrolled. Sensitivity and specificity of the test with combined results from nasal and throat swab samples were 74.0% (131/177) and 99.7% (351/352), respectively, compared to RT-PCR. The POC test was as sensitive for influenza virus B as for influenza virus A (74.4% [64/86] versus 73.6% [67/91]). The positivity rate was associated with lower cycle threshold values (a marker for higher viral loads), sample type (73.6% for nasal swab versus 52.4% for throat swab), and younger age. A total of 210 (18.7%) out of 1,126 MSD tests failed, and for 34 (6%) of patients, both test samples failed (these were excluded from the performance analysis). Subtyping could be assessed only for influenza virus A/H3N2, as 1977 H1N1 was not circulating at the time and no H5N1-infected patients were enrolled, and was successful only in 9/54 patients infected with H3 influenza virus who had a positive POC test result for influenza virus A. This novel POC test provided highly sensitive detection of influenza viruses A and B compared to the reported sensitivities of other rapid tests. However, 18.7% of tests failed for technical reasons and subtyping for H3 was poor. Drawbacks to the technology include the requirement for a dedicated reader instrument and the need for continual updating of subtyping antibodies within the test array.
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Current research on respiratory viral infections: XIIth International Symposium.
Antivir. Ther. (Lond.)
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The XIIth International Symposium on Respiratory Viral Infections was convened by The Macrae Group (New York, NY, USA) in Taipei, Taiwan on 11-14 March 2010. This annual symposium provides a forum to discuss recent advances in respiratory virus research in an interdisciplinary fashion with specialists ranging from basic virology, epidemiology, vaccines, antivirals and management strategies. The 2010 symposium provided a detailed examination of lessons learned from the 2009 influenza pandemic with a common theme, emphasized by many speakers, being the importance of international collaboration and cooperation in responding to new infectious disease threats.
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Efficacy of combined therapy with amantadine, oseltamivir, and ribavirin in vivo against susceptible and amantadine-resistant influenza A viruses.
PLoS ONE
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The limited efficacy of existing antiviral therapies for influenza--coupled with widespread baseline antiviral resistance--highlights the urgent need for more effective therapy. We describe a triple combination antiviral drug (TCAD) regimen composed of amantadine, oseltamivir, and ribavirin that is highly efficacious at reducing mortality and weight loss in mouse models of influenza infection. TCAD therapy was superior to dual and single drug regimens in mice infected with drug-susceptible, low pathogenic A/H5N1 (A/Duck/MN/1525/81) and amantadine-resistant 2009 A/H1N1 influenza (A/California/04/09). Treatment with TCAD afforded >90% survival in mice infected with both viruses, whereas treatment with dual and single drug regimens resulted in 0% to 60% survival. Importantly, amantadine had no activity as monotherapy against the amantadine-resistant virus, but demonstrated dose-dependent protection in combination with oseltamivir and ribavirin, indicative that amantadines activity had been restored in the context of TCAD therapy. Furthermore, TCAD therapy provided survival benefit when treatment was delayed until 72 hours post-infection, whereas oseltamivir monotherapy was not protective after 24 hours post-infection. These findings demonstrate in vivo efficacy of TCAD therapy and confirm previous reports of the synergy and broad spectrum activity of TCAD therapy against susceptible and resistant influenza strains in vitro.
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Why should I comply? Sellers accounts for (non-)compliance with legal age limits for alcohol sales.
Subst Abuse Treat Prev Policy
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Availability is an important predictor of early and excessive alcohol consumption by adolescents. Many countries have implemented age limits to prevent underage purchases of alcohol. However, shop-floor compliance with these age limits appears to be problematic. This study addresses the issue of non-compliance with age limits. Which measures do vendors take to avoid underage alcohol sales, and what do they report as important reasons to comply or not with age limits for alcohol sales?
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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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.