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1.
JMIR Res Protoc ; 9(1): e16320, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31922493

RESUMO

BACKGROUND: Alcohol warning labels are a promising, well-targeted strategy to increase public awareness of alcohol-related health risks and support more informed and safer use. However, evidence of their effectiveness in real-world settings remains limited and inconclusive. OBJECTIVE: This paper presents a protocol for a real-world study examining the population-level impact of enhanced alcohol warning labels with a cancer message; national drinking guidelines; and standard drink information on attention, processing, and alcohol-related behaviors among consumers in Canada. Postimplementation modifications to the original protocol due to interference by national alcohol industry representatives are also described. METHODS: This quasi-experimental study involved partnering with local governments in two northern Canadian territories already applying alcohol warning labels on alcohol containers for sale in liquor stores. The study tested an 8-month intervention consisting of three new enhanced, rotating alcohol warning labels in an intervention site (Whitehorse, Yukon) relative to a comparison site (Yellowknife, Northwest Territories) where labelling practices would remain unchanged. Pre-post surveys were conducted at both sites to measure changes in awareness and processing of label messages, alcohol-related knowledge, and behaviors. Liquor store transaction data were collected from both sites to assess changes in population-level alcohol consumption. The intervention was successfully implemented for 1 month before it was halted due to complaints from the alcohol industry. The government of the intervention site allowed the study to proceed after a 2-month pause, on the condition that the cancer warning label was removed from rotation. Modifications to the protocol included applying the two remaining enhanced labels for the balance of the intervention and adding a third wave of surveys during the 2-month pause to capture any impact of the cancer label. RESULTS: This study protocol describes a real-world quasi-experimental study that aimed to test the effectiveness of new enhanced alcohol warning labels as a tool to support consumers in making more informed and safer alcohol choices. Alcohol industry interference shortly after implementation compromised both the intervention and the original study design; however, the study design was modified to enable completion of three waves of surveys with cohort participants (n=2049) and meet the study aims. CONCLUSIONS: Findings from this study will directly inform alcohol labelling policies in Canada and internationally and provide further insight into the alcohol industry's attempts to disrupt research in this area. Additional unimpeded real-world evaluations of enhanced alcohol warning labels are recommended. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/16320.

3.
Emerg Microbes Infect ; 7(1): 10, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29410402

RESUMO

Human adenoviruses (HAdVs) are uniquely important "model organisms" as they have been used to elucidate fundamental biological processes, are recognized as complex pathogens, and are used as remedies for human health. As pathogens, HAdVs may effect asymptomatic or mild and severe symptomatic disease upon their infection of respiratory, ocular, gastrointestinal, and genitourinary systems. High-resolution genomic data have enhanced the understanding of HAdV epidemiology, with recombination recognized as an important and major pathway in the molecular evolution and genesis of emergent HAdV pathogens. To support this view and to actualize an algorithm for identifying, characterizing, and typing novel HAdVs, we determined the DNA sequence of 95 isolates from archives containing historically important pathogens and collections housing currently circulating strains to be sequenced. Of the 85 samples that were completely sequenced, 18 novel recombinants within species HAdV-B and D were identified. Two HAdV-D genomes were found to contain novel penton base and fiber genes with significant divergence from known molecular types. In this data set, we found additional isolates of HAdV-D53 and HAdV-D58, two novel genotypes recognized recently using genomics. This supports the thesis that novel HAdV genotypes are not limited to "one-time" appearances of the prototype but are of importance in HAdV epidemiology. These data underscore the significance of lateral genomic transfer in HAdV evolution and reinforce the potential public health impact of novel genotypes of HAdVs emerging in the population.


Assuntos
Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , DNA Viral/genética , Genoma Viral , Genômica , Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/patogenicidade , Sequência de Bases , Biologia Computacional , Evolução Molecular , Genótipo , Humanos , Filogenia , Recombinação Genética , Análise de Sequência de DNA
5.
PLoS Negl Trop Dis ; 11(8): e0005693, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28771475

RESUMO

Venezuelan equine encephalitis (VEE) complex alphaviruses are important re-emerging arboviruses that cause life-threatening disease in equids during epizootics as well as spillover human infections. We conducted a comprehensive analysis of VEE complex alphaviruses by sequencing the genomes of 94 strains and performing phylogenetic analyses of 130 isolates using complete open reading frames for the nonstructural and structural polyproteins. Our analyses confirmed purifying selection as a major mechanism influencing the evolution of these viruses as well as a confounding factor in molecular clock dating of ancestors. Times to most recent common ancestors (tMRCAs) could be robustly estimated only for the more recently diverged subtypes; the tMRCA of the ID/IAB/IC/II and IE clades of VEE virus (VEEV) were estimated at ca. 149-973 years ago. Evolution of the IE subtype has been characterized by a significant evolutionary shift from the rest of the VEEV complex, with an increase in structural protein substitutions that are unique to this group, possibly reflecting adaptation to its unique enzootic mosquito vector Culex (Melanoconion) taeniopus. Our inferred tree topologies suggest that VEEV is maintained primarily in situ, with only occasional spread to neighboring countries, probably reflecting the limited mobility of rodent hosts and mosquito vectors.


Assuntos
Vírus da Encefalite Equina Venezuelana/genética , Encefalomielite Equina Venezuelana/epidemiologia , Evolução Molecular , Doenças dos Cavalos/virologia , América , Sequência de Aminoácidos , Animais , Culex/virologia , Vírus da Encefalite Equina Venezuelana/isolamento & purificação , Encefalomielite Equina Venezuelana/virologia , Doenças dos Cavalos/epidemiologia , Cavalos/virologia , Humanos , Insetos Vetores/virologia , Filogenia
6.
Sci Rep ; 6: 26311, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27212633

RESUMO

Respiratory Syncytial Virus (RSV) is responsible for considerable morbidity and mortality worldwide and is the most important respiratory viral pathogen in infants. Extensive sequence variability within and between RSV group A and B viruses and the ability of multiple clades and sub-clades of RSV to co-circulate are likely mechanisms contributing to the evasion of herd immunity. Surveillance and large-scale whole-genome sequencing of RSV is currently limited but would help identify its evolutionary dynamics and sites of selective immune evasion. In this study, we performed complete-genome next-generation sequencing of 92 RSV isolates from infants in central Tennessee during the 2012-2014 RSV seasons. We identified multiple co-circulating clades of RSV from both the A and B groups. Each clade is defined by signature N- and O-linked glycosylation patterns. Analyses of specific RSV genes revealed high rates of positive selection in the attachment (G) gene. We identified RSV-A viruses in circulation with and without a recently reported 72-nucleotide G gene sequence duplication. Furthermore, we show evidence of convergent evolution of G gene sequence duplication and fixation over time, which suggests a potential fitness advantage of RSV with the G sequence duplication.


Assuntos
Evolução Molecular , Genoma Viral , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/genética , Proteínas do Envelope Viral/genética , Teorema de Bayes , Feminino , Duplicação Gênica , Glicosilação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Estudos Longitudinais , Masculino , Filogenia , Sequências Repetitivas de Ácido Nucleico , Infecções por Vírus Respiratório Sincicial/epidemiologia , Análise de Sequência de RNA , Tennessee/epidemiologia , Proteínas do Envelope Viral/química
7.
Nature ; 526(7571): 122-5, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26416728

RESUMO

Influenza A viruses pose a major public health threat by causing seasonal epidemics and sporadic pandemics. Their epidemiological success relies on airborne transmission from person to person; however, the viral properties governing airborne transmission of influenza A viruses are complex. Influenza A virus infection is mediated via binding of the viral haemagglutinin (HA) to terminally attached α2,3 or α2,6 sialic acids on cell surface glycoproteins. Human influenza A viruses preferentially bind α2,6-linked sialic acids whereas avian influenza A viruses bind α2,3-linked sialic acids on complex glycans on airway epithelial cells. Historically, influenza A viruses with preferential association with α2,3-linked sialic acids have not been transmitted efficiently by the airborne route in ferrets. Here we observe efficient airborne transmission of a 2009 pandemic H1N1 (H1N1pdm) virus (A/California/07/2009) engineered to preferentially bind α2,3-linked sialic acids. Airborne transmission was associated with rapid selection of virus with a change at a single HA site that conferred binding to long-chain α2,6-linked sialic acids, without loss of α2,3-linked sialic acid binding. The transmissible virus emerged in experimentally infected ferrets within 24 hours after infection and was remarkably enriched in the soft palate, where long-chain α2,6-linked sialic acids predominate on the nasopharyngeal surface. Notably, presence of long-chain α2,6-linked sialic acids is conserved in ferret, pig and human soft palate. Using a loss-of-function approach with this one virus, we demonstrate that the ferret soft palate, a tissue not normally sampled in animal models of influenza, rapidly selects for transmissible influenza A viruses with human receptor (α2,6-linked sialic acids) preference.


Assuntos
Adaptação Fisiológica , Vírus da Influenza A Subtipo H1N1/fisiologia , Palato Mole/metabolismo , Palato Mole/virologia , Receptores Virais/metabolismo , Seleção Genética , Adaptação Fisiológica/genética , Animais , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Feminino , Furões/virologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Vírus da Influenza A Subtipo H1N1/química , Vírus da Influenza A Subtipo H1N1/genética , Masculino , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Palato Mole/química , Sistema Respiratório/citologia , Sistema Respiratório/metabolismo , Sistema Respiratório/virologia , Seleção Genética/genética , Ácidos Siálicos/química , Ácidos Siálicos/metabolismo , Suínos/virologia
8.
mBio ; 5(6): e02011, 2014 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-25370495

RESUMO

UNLABELLED: Deep sequencing of RNAs produced by Zaire ebolavirus (EBOV) or the Angola strain of Marburgvirus (MARV-Ang) identified novel viral and cellular mechanisms that diversify the coding and noncoding sequences of viral mRNAs and genomic RNAs. We identified previously undescribed sites within the EBOV and MARV-Ang mRNAs where apparent cotranscriptional editing has resulted in the addition of non-template-encoded residues within the EBOV glycoprotein (GP) mRNA, the MARV-Ang nucleoprotein (NP) mRNA, and the MARV-Ang polymerase (L) mRNA, such that novel viral translation products could be produced. Further, we found that the well-characterized EBOV GP mRNA editing site is modified at a high frequency during viral genome RNA replication. Additionally, editing hot spots representing sites of apparent adenosine deaminase activity were found in the MARV-Ang NP 3'-untranslated region. These studies identify novel filovirus-host interactions and reveal production of a greater diversity of filoviral gene products than was previously appreciated. IMPORTANCE: This study identifies novel mechanisms that alter the protein coding capacities of Ebola and Marburg virus mRNAs. Therefore, filovirus gene expression is more complex and diverse than previously recognized. These observations suggest new directions in understanding the regulation of filovirus gene expression.


Assuntos
Ebolavirus/genética , Marburgvirus/genética , Edição de RNA , RNA Mensageiro/metabolismo , Replicação Viral , Animais , Linhagem Celular , Chlorocebus aethiops , Ebolavirus/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno , Humanos , Marburgvirus/fisiologia , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Viral/genética , RNA Viral/metabolismo , Análise de Sequência de DNA
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