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1.
J Pharmacol Exp Ther ; 389(2): 229-242, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38453526

RESUMO

The drug-drug interaction (DDI) between amiodarone (AMIO) and sofosbuvir (SOF), a direct-acting hepatitis-C NS5B nucleotide polymerase inhibitor, has been associated with severe bradyarrhythmia in patients. Recent cryo-EM data has revealed that this DDI occurs at the α-subunit of L-type Cav channels, with AMIO binding at the fenestration site and SOF [or MSD nucleotide inhibitor #1 (MNI-1): analog of SOF] binding at the central cavity of the conductance pathway. In this study, we investigated the DDI between 21 AMIO analogs, including dronedarone (DRON) and MNI-1 (or SOF) in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and hCav1.2 models. Our findings indicate that among the tested AMIO analogs in hiPSC-CMs at clinically relevant concentrations, only three analogs (AA-9, AA-10, and AA-17) were able to effectively substitute for AMIO in this DDI with 1 µM MNI-1. This highlights the importance of the diethyl amino group of AMIO for interacting with MNI-1. In the hCav1.2 model, desethylamiodarone (AA-12) demonstrated synergy with 90 µM MNI-1, while three other analogs with modifications to the position of the diethyl amino group or removal of iodo groups showed weaker synergy with 90 µM MNI-1. Interestingly, DRON did not exhibit any interaction with 270 µM SOF or 90 µM MNI-1, suggesting that it could safely replace AMIO in patients requiring SOF treatment, other clinically relevant differences considered. Overall, our functional data align with the cryo-EM data, highlighting that this DDI is dependent on the structure of AMIO and cardiomyocyte resting membrane potential. SIGNIFICANCE STATEMENT: Our findings point to specific residues in the AMIO molecule playing a critical role in the DDI between AMIO and MNI-1 (SOF analog), confirming cryo-EM results. Applied at clinically relevant AMIO's concentrations or projected MNI-1's concentrations at the resting potentials mimicking the sinoatrial node, this DDI significantly slowed down or completely inhibited the beating of hiPSC-CMs. Finally, these in vitro results support the safe replacement of AMIO (Cordarone) with DRON (Multaq) for patients requiring SOF treatment, other clinical caveats considered.


Assuntos
Amiodarona , Células-Tronco Pluripotentes Induzidas , Humanos , Amiodarona/farmacologia , Amiodarona/metabolismo , Nucleotídeos/farmacologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Interações Medicamentosas , Relação Estrutura-Atividade
2.
PLoS Comput Biol ; 19(3): e1010885, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36972311

RESUMO

Surface antigens of pathogens are commonly targeted by vaccine-elicited antibodies but antigenic variability, notably in RNA viruses such as influenza, HIV and SARS-CoV-2, pose challenges for control by vaccination. For example, influenza A(H3N2) entered the human population in 1968 causing a pandemic and has since been monitored, along with other seasonal influenza viruses, for the emergence of antigenic drift variants through intensive global surveillance and laboratory characterisation. Statistical models of the relationship between genetic differences among viruses and their antigenic similarity provide useful information to inform vaccine development, though accurate identification of causative mutations is complicated by highly correlated genetic signals that arise due to the evolutionary process. Here, using a sparse hierarchical Bayesian analogue of an experimentally validated model for integrating genetic and antigenic data, we identify the genetic changes in influenza A(H3N2) virus that underpin antigenic drift. We show that incorporating protein structural data into variable selection helps resolve ambiguities arising due to correlated signals, with the proportion of variables representing haemagglutinin positions decisively included, or excluded, increased from 59.8% to 72.4%. The accuracy of variable selection judged by proximity to experimentally determined antigenic sites was improved simultaneously. Structure-guided variable selection thus improves confidence in the identification of genetic explanations of antigenic variation and we also show that prioritising the identification of causative mutations is not detrimental to the predictive capability of the analysis. Indeed, incorporating structural information into variable selection resulted in a model that could more accurately predict antigenic assay titres for phenotypically-uncharacterised virus from genetic sequence. Combined, these analyses have the potential to inform choices of reference viruses, the targeting of laboratory assays, and predictions of the evolutionary success of different genotypes, and can therefore be used to inform vaccine selection processes.


Assuntos
COVID-19 , Vírus da Influenza A , Influenza Humana , Humanos , Influenza Humana/prevenção & controle , Vírus da Influenza A Subtipo H3N2/genética , Teorema de Bayes , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , SARS-CoV-2 , Antígenos Virais/genética , Genótipo , Fenótipo , Anticorpos Antivirais/genética
3.
J Gen Virol ; 104(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36800222

RESUMO

The COVID-19 pandemic is the first to have emerged when Next Generation Sequencing was readily available and it has played the major role in following evolution of the causative agent, Severe Acute Respiratory Syndrome Coronavirus 2. Response to the pandemic was greatly facilitated though use of existing influenza surveillance networks: World Health Organization (WHO) Global Influenza Surveillance and Response System (GISRS), focussing largely on human influenza, and the OFFLU network of expertise on avian influenza established by the Food and Agricultural Organization of the United Nations (FAO) and the World Organization for Animal Health (WOAH). Data collection/deposition platforms associated with these networks, notably WHO's FluNet and the Global Initiative on Sharing All Influenza Data (GISAID) were/are being used intensely. Measures introduced to combat COVID-19 resulted in greatly decreased circulation of human seasonal influenza viruses for approximately 2 years, but circulation continued in the animal sector with an upsurge in the spread of highly pathogenic avian influenza subtype H5N1 with large numbers of wild bird deaths, culling of many poultry flocks and sporadic spill over into mammalian species, including humans, thereby increasing pandemic risk potential. While there are proposals/implementations to extend use of GISRS and GISAID to other infectious disease agents (e.g. Respiratory Syncytial Virus and Monkeypox), there is need to ensure that influenza surveillance is maintained and improved in both human and animal sectors in a sustainable manner to be truly prepared (early detection) for the next influenza pandemic.


Assuntos
COVID-19 , Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Influenza Humana , Orthomyxoviridae , Animais , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Influenza Aviária/epidemiologia , Pandemias , COVID-19/epidemiologia , Mamíferos
4.
J Virol ; 96(3): e0192821, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-34787455

RESUMO

From 2014 to week 07/2020 the Centre for Health Protection in Hong Kong conducted screening for influenza C virus (ICV). A retrospective analysis of ICV detections to week 26/2019 revealed persistent low-level circulation with outbreaks occurring biennially in the winters of 2015 to 2016 and 2017 to 2018 (R. S. Daniels et al., J Virol 94:e01051-20, 2020, https://doi.org/10.1128/JVI.01051-20). Here, we report on an outbreak occurring in 2019 to 2020, reinforcing the observation of biennial seasonality in Hong Kong. All three outbreaks occurred in similar time frames, were subsequently dwarfed by seasonal epidemics of influenza types A and B, and were caused by similar proportions of C/Kanagawa/1/76 (K)-lineage and C/São Paulo/378/82 S1- and S2-sublineage viruses. Ongoing genetic drift was observed in all genes, with some evidence of amino acid substitution in the hemagglutinin-esterase-fusion (HEF) glycoprotein possibly associated with antigenic drift. A total of 61 ICV genomes covering the three outbreaks were analyzed for reassortment, and 9 different reassortant constellations were identified, 1 K-lineage, 4 S1-sublineage, and 4 S2-sublineage, with 6 of these being identified first in the 2019-1920 outbreak (2 S2-lineage and 4 S1-lineage). The roles that virus interference/enhancement, ICV persistent infection, genome evolution, and reassortment might play in the observed seasonality of ICV in Hong Kong are discussed. IMPORTANCE Influenza C virus (ICV) infection of humans is common, with the great majority of people being infected during childhood, though reinfection can occur throughout life. While infection normally results in "cold-like" symptoms, severe disease cases have been reported in recent years. However, knowledge of ICV is limited due to poor systematic surveillance and an inability to propagate the virus in large amounts in the laboratory. Following recent systematic surveillance in Hong Kong SAR, China, and direct ICV gene sequencing from clinical specimens, a 2-year cycle of disease outbreaks (epidemics) has been identified, with gene mixing playing a significant role in ICV evolution. Studies like those reported here are key to developing an understanding of the impact of influenza C virus infection in humans, notably where comorbidities exist and severe respiratory disease can develop.


Assuntos
Surtos de Doenças , Gammainfluenzavirus/classificação , Gammainfluenzavirus/genética , Influenza Humana/epidemiologia , Influenza Humana/virologia , Vírus Reordenados , Hemaglutininas Virais/química , Hemaglutininas Virais/genética , Hong Kong/epidemiologia , Humanos , Modelos Moleculares , Mutação , Filogenia , Vigilância em Saúde Pública , Análise de Sequência de DNA , Relação Estrutura-Atividade , Proteínas Virais de Fusão/química , Proteínas Virais de Fusão/genética
7.
PLoS Pathog ; 17(3): e1009330, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33662023

RESUMO

Pigs are natural hosts for the same subtypes of influenza A viruses as humans and integrally involved in virus evolution with frequent interspecies transmissions in both directions. The emergence of the 2009 pandemic H1N1 virus illustrates the importance of pigs in evolution of zoonotic strains. Here we generated pig influenza-specific monoclonal antibodies (mAbs) from H1N1pdm09 infected pigs. The mAbs recognized the same two major immunodominant haemagglutinin (HA) epitopes targeted by humans, one of which is not recognized by post-infection ferret antisera that are commonly used to monitor virus evolution. Neutralizing activity of the pig mAbs was comparable to that of potent human anti-HA mAbs. Further, prophylactic administration of a selected porcine mAb to pigs abolished lung viral load and greatly reduced lung pathology but did not eliminate nasal shedding of virus after H1N1pdm09 challenge. Hence mAbs from pigs, which target HA can significantly reduce disease severity. These results, together with the comparable sizes of pigs and humans, indicate that the pig is a valuable model for understanding how best to apply mAbs as therapy in humans and for monitoring antigenic drift of influenza viruses in humans, thereby providing information highly relevant to making influenza vaccine recommendations.


Assuntos
Anticorpos Antivirais/farmacologia , Epitopos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Influenza Humana/tratamento farmacológico , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Hemaglutininas/imunologia , Hemaglutininas/farmacologia , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Suínos
8.
PLoS Pathog ; 17(2): e1009352, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33635919

RESUMO

Serological and plasmablast responses and plasmablast-derived IgG monoclonal antibodies (MAbs) have been analysed in three COVID-19 patients with different clinical severities. Potent humoral responses were detected within 3 weeks of onset of illness in all patients and the serological titre was elicited soon after or concomitantly with peripheral plasmablast response. An average of 13.7% and 3.5% of plasmablast-derived MAbs were reactive with virus spike glycoprotein or nucleocapsid, respectively. A subset of anti-spike (10 of 32) antibodies cross-reacted with other betacoronaviruses tested and harboured extensive somatic mutations, indicative of an expansion of memory B cells upon SARS-CoV-2 infection. Fourteen of 32 anti-spike MAbs, including five anti-receptor-binding domain (RBD), three anti-non-RBD S1 and six anti-S2, neutralised wild-type SARS-CoV-2 in independent assays. Anti-RBD MAbs were further grouped into four cross-inhibiting clusters, of which six antibodies from three separate clusters blocked the binding of RBD to ACE2 and five were neutralising. All ACE2-blocking anti-RBD antibodies were isolated from two recovered patients with prolonged fever, which is compatible with substantial ACE2-blocking response in their sera. Finally, the identification of non-competing pairs of neutralising antibodies would offer potential templates for the development of prophylactic and therapeutic agents against SARS-CoV-2.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/genética , Células Produtoras de Anticorpos/imunologia , Sítios de Ligação , Epitopos , Humanos , Imunoglobulina G/imunologia , Nucleocapsídeo/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
9.
Biochem J ; 478(13): 2405-2423, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34198322

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global public health challenge. While the efficacy of vaccines against emerging and future virus variants remains unclear, there is a need for therapeutics. Repurposing existing drugs represents a promising and potentially rapid opportunity to find novel antivirals against SARS-CoV-2. The virus encodes at least nine enzymatic activities that are potential drug targets. Here, we have expressed, purified and developed enzymatic assays for SARS-CoV-2 nsp13 helicase, a viral replication protein that is essential for the coronavirus life cycle. We screened a custom chemical library of over 5000 previously characterized pharmaceuticals for nsp13 inhibitors using a fluorescence resonance energy transfer-based high-throughput screening approach. From this, we have identified FPA-124 and several suramin-related compounds as novel inhibitors of nsp13 helicase activity in vitro. We describe the efficacy of these drugs using assays we developed to monitor SARS-CoV-2 growth in Vero E6 cells.


Assuntos
Antivirais/química , Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , RNA Helicases/antagonistas & inibidores , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Chlorocebus aethiops , Ensaios Enzimáticos , Transferência Ressonante de Energia de Fluorescência , Ensaios de Triagem em Larga Escala , RNA Helicases/metabolismo , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Suramina/farmacologia , Células Vero , Proteínas não Estruturais Virais/metabolismo
10.
J Gen Virol ; 102(10)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34596510

RESUMO

Neuraminidase (NA) inhibitors (NAI), oseltamivir and zanamivir, are the main antiviral medications for influenza and monitoring of susceptibility to these antivirals is routinely done by determining 50 % inhibitory concentrations (IC50) with MUNANA substrate. During 2010-2019, levels of A(H3N2) viruses presenting reduced NAI inhibition (RI) were low (~0.75 %) but varied year-on-year. The highest proportions of viruses showing RI were observed during the 2013-2014, 2016-2017 and 2017-2018 Northern Hemisphere seasons. The majority of RI viruses were found to contain positively charged NA amino acid substitutions of N329K, K/S329R, S331R or S334R, being notably higher during the 2016-2017 season. Sialidase activity kinetics were determined for viruses of RI phenotype and contemporary wild-type (WT) viruses showing close genetic relatedness and displaying normal inhibition (NI). RI phenotypes resulted from reduced sialidase activity compared to relevant WT viruses. Those containing S329R or N329K or S331R showed markedly higher Km for the substrate and Ki values for NAIs, while those with S334R showed smaller effects. Substitutions at N329 and S331 disrupt a glycosylation sequon (NDS), confirmed to be utilised by mass spectrometry. However, gain of positive charge at all three positions was the major factor influencing the kinetic effects, not loss of glycosylation. Because of the altered enzyme characteristics NAs carrying these substitutions cannot be assessed reliably for susceptibility to NAIs using standard MUNANA-based assays due to reductions in the affinity of the enzyme for its substrate and the concentration of the substrate usually used.


Assuntos
Vírus da Influenza A Subtipo H3N2/enzimologia , Neuraminidase/metabolismo , Substituição de Aminoácidos , Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Genes Virais , Glicosilação , Sequenciamento de Nucleotídeos em Larga Escala , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Cinética , Modelos Moleculares , Neuraminidase/antagonistas & inibidores , Neuraminidase/química , Neuraminidase/genética , Oseltamivir/farmacologia , Conformação Proteica , Zanamivir/farmacologia
11.
J Virol ; 94(21)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32817211

RESUMO

In 2014, the Centre for Health Protection in Hong Kong introduced screening for influenza C virus (ICV) as part of its routine surveillance for infectious agents in specimens collected from patients presenting with symptoms of respiratory viral infection, including influenza-like illness (ILI). A retrospective analysis of ICV detections up to week 26 of 2019 revealed persistent low-level circulation, with two outbreaks having occurred in the winters of 2015 to 2016 and 2017 to 2018. These outbreaks occurred at the same time as, and were dwarfed by, seasonal epidemics of influenza types A and B. Gene sequencing studies on stored ICV-positive clinical specimens from the two outbreaks have shown that the hemagglutinin-esterase (HE) genes of the viruses fall into two of the six recognized genetic lineages (represented by C/Kanagawa/1/76 and C/São Paulo/378/82), with there being significant genetic drift compared to earlier circulating viruses within both lineages. The location of a number of encoded amino acid substitutions in hemagglutinin-esterase fusion (HEF) glycoproteins suggests that antigenic drift may also have occurred. Observations of ICV outbreaks in other countries, with some of the infections being associated with severe disease, indicates that ICV infection has the potential to have significant clinical and health care impacts in humans.IMPORTANCE Influenza C virus infection of humans is common, and reinfection can occur throughout life. While symptoms are generally mild, severe disease cases have been reported, but knowledge of the virus is limited, as little systematic surveillance for influenza C virus is conducted and the virus cannot be studied by classical virologic methods because it cannot be readily isolated in laboratories. A combination of systematic surveillance in Hong Kong SAR, China, and new gene sequencing methods has been used in this study to assess influenza C virus evolution and provides evidence for a 2-year cycle of disease outbreaks. The results of studies like that reported here are key to developing an understanding of the impact of influenza C virus infection in humans and how virus evolution might be associated with epidemics.


Assuntos
Surtos de Doenças , Gammainfluenzavirus/genética , Hemaglutininas Virais/genética , Influenza Humana/epidemiologia , Mutação , Proteínas Virais de Fusão/genética , Adolescente , Adulto , Idoso , Substituição de Aminoácidos , Criança , Pré-Escolar , Monitoramento Epidemiológico , Feminino , Expressão Gênica , Hemaglutininas Virais/química , Hemaglutininas Virais/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Hong Kong/epidemiologia , Humanos , Lactente , Influenza Humana/patologia , Influenza Humana/virologia , Gammainfluenzavirus/enzimologia , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Epidemiologia Molecular , Filogenia , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Estudos Retrospectivos , Proteínas Virais de Fusão/química , Proteínas Virais de Fusão/metabolismo
12.
J Virol ; 94(4)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31748388

RESUMO

The majority of antibodies induced by influenza neuraminidase (NA), like those against hemagglutinin (HA), are relatively specific to viruses isolated within a limited time window, as seen in serological studies and the analysis of many murine monoclonal antibodies (MAbs). We report three broadly reactive human MAbs targeting N1 NA. Two were isolated from a young adult vaccinated with trivalent influenza vaccine (TIV), which inhibited N1 NA from viruses isolated from humans over a period of a hundred years. The third antibody, isolated from a child with acute mild H7N9 infection, inhibited both group 1 N1 and group 2 N9 NAs. In addition, the antibodies cross-inhibited the N1 NAs of highly pathogenic avian H5N1 influenza viruses. These antibodies are protective in prophylaxis against seasonal H1N1 viruses in mice. This study demonstrates that human antibodies to N1 NA with exceptional cross-reactivity can be recalled by vaccination and highlights the importance of standardizing the NA antigen in seasonal vaccines to offer optimal protection.IMPORTANCE Antibodies to the influenza virus NA can provide protection against influenza disease. Analysis of human antibodies to NA lags behind that of antibodies to HA. We show that human monoclonal antibodies against NA induced by vaccination and infection can be very broadly reactive, with the ability to inhibit a wide spectrum of N1 NAs on viruses isolated between 1918 and 2018. This suggests that antibodies to NA may be a useful therapy and that the efficacy of influenza vaccines could be enhanced by ensuring the appropriate content of NA antigen.


Assuntos
Proteção Cruzada/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Neuraminidase/imunologia , Animais , Anticorpos Monoclonais/imunologia , Criança , Reações Cruzadas/imunologia , Cães , Feminino , Células HEK293 , Hemaglutininas/imunologia , Humanos , Imunização Passiva , Vírus da Influenza A Subtipo H1N1/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Subtipo H7N9 do Vírus da Influenza A/imunologia , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Neuraminidase/metabolismo , Infecções por Orthomyxoviridae/virologia , Vacinação , Adulto Jovem
13.
Rev Med Virol ; 30(3): e2099, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32135031

RESUMO

The panzootic caused by A/goose/Guangdong/1/96-lineage highly pathogenic avian influenza (HPAI) A(H5) viruses has occurred in multiple waves since 1996. From 2013 onwards, clade 2.3.4.4 viruses of subtypes A(H5N2), A(H5N6), and A(H5N8) emerged to cause panzootic waves of unprecedented magnitude among avian species accompanied by severe losses to the poultry industry around the world. Clade 2.3.4.4 A(H5) viruses have expanded in distinct geographical and evolutionary pathways likely via long distance migratory bird dispersal onto several continents and by poultry trade among neighboring countries. Coupled with regional circulation, the viruses have evolved further by reassorting with local viruses. As of February 2019, there have been 23 cases of humans infected with clade 2.3.4.4 H5N6 viruses, 16 (70%) of which had fatal outcomes. To date, no HPAI A(H5) virus has caused sustainable human-to-human transmission. However, due to the lack of population immunity in humans and ongoing evolution of the virus, there is a continuing risk that clade 2.3.4.4 A(H5) viruses could cause an influenza pandemic if the ability to transmit efficiently among humans was gained. Therefore, multisectoral collaborations among the animal, environmental, and public health sectors are essential to conduct risk assessments and develop countermeasures to prevent disease and to control spread. In this article, we describe an assessment of the likelihood of clade 2.3.4.4 A(H5) viruses gaining human-to-human transmissibility and impact on human health should such human-to-human transmission occur. This structured analysis assessed properties of the virus, attributes of the human population, and ecology and epidemiology of these viruses in animal hosts.


Assuntos
Vírus da Influenza A Subtipo H5N2/fisiologia , Influenza Aviária/transmissão , Influenza Humana/transmissão , Doenças das Aves Domésticas/transmissão , Animais , Humanos , Vírus da Influenza A Subtipo H5N2/genética , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Pandemias , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia
14.
Nature ; 523(7559): 217-20, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26053121

RESUMO

Understanding the spatiotemporal patterns of emergence and circulation of new human seasonal influenza virus variants is a key scientific and public health challenge. The global circulation patterns of influenza A/H3N2 viruses are well characterized, but the patterns of A/H1N1 and B viruses have remained largely unexplored. Here we show that the global circulation patterns of A/H1N1 (up to 2009), B/Victoria, and B/Yamagata viruses differ substantially from those of A/H3N2 viruses, on the basis of analyses of 9,604 haemagglutinin sequences of human seasonal influenza viruses from 2000 to 2012. Whereas genetic variants of A/H3N2 viruses did not persist locally between epidemics and were reseeded from East and Southeast Asia, genetic variants of A/H1N1 and B viruses persisted across several seasons and exhibited complex global dynamics with East and Southeast Asia playing a limited role in disseminating new variants. The less frequent global movement of influenza A/H1N1 and B viruses coincided with slower rates of antigenic evolution, lower ages of infection, and smaller, less frequent epidemics compared to A/H3N2 viruses. Detailed epidemic models support differences in age of infection, combined with the less frequent travel of children, as probable drivers of the differences in the patterns of global circulation, suggesting a complex interaction between virus evolution, epidemiology, and human behaviour.


Assuntos
Variação Antigênica , Vírus da Influenza A/genética , Vírus da Influenza B/genética , Influenza Humana/epidemiologia , Influenza Humana/virologia , Fatores Etários , Saúde Global , Humanos , Vírus da Influenza A/classificação , Vírus da Influenza B/classificação , Filogenia , Filogeografia , Estações do Ano
15.
World J Urol ; 38(2): 263-268, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31606787

RESUMO

PURPOSE: To review the literature regarding the use of penile ultrasound in the evaluation and management of Peyronie's disease. METHODS: A literature review was performed using PubMed from 1980 to 2018 using the keywords: Peyronie's disease, ultrasound, sonography, calcification, penile fracture, and penile hematoma. Articles were reviewed for study size, image protocols, and findings. In addition, we reviewed images from 227 penile ultrasounds performed on Peyronie's disease patients at the Walter Reed National Military Medical Center between 2014 and 2018. RESULTS: Through extensive urological and radiographic literature review over the last four decades, common patterns and characteristic of Peyronie's plaques were identified. These characteristics are not always delineated by physical examination alone. The ultrasound images often added objective information including etiology of erectile dysfunction and location or plaques, and presence of calcifications which aid in patient counseling and treatment protocols. CONCLUSIONS: The use of B-mode ultrasound with color Doppler in the evaluation and management of Peyronie's disease is a quick, cost-effective process that provides objective information that can assist the urologist in the treatment of patients with Peyronie's disease.


Assuntos
Induração Peniana/diagnóstico , Pênis/diagnóstico por imagem , Ultrassonografia/estatística & dados numéricos , Humanos , Masculino
16.
Nature ; 511(7510): 475-7, 2014 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-24870229

RESUMO

H10N8 follows H7N9 and H5N1 as the latest in a line of avian influenza viruses that cause serious disease in humans and have become a threat to public health. Since December 2013, three human cases of H10N8 infection have been reported, two of whom are known to have died. To gather evidence relating to the epidemic potential of H10 we have determined the structure of the haemagglutinin of a previously isolated avian H10 virus and we present here results relating especially to its receptor-binding properties, as these are likely to be major determinants of virus transmissibility. Our results show, first, that the H10 virus possesses high avidity for human receptors and second, from the crystal structure of the complex formed by avian H10 haemagglutinin with human receptor, it is clear that the conformation of the bound receptor has characteristics of both the 1918 H1N1 pandemic virus and the human H7 viruses isolated from patients in 2013 (ref. 3). We conclude that avian H10N8 virus has sufficient avidity for human receptors to account for its infection of humans but that its preference for avian receptors should make avian-receptor-rich human airway mucins an effective block to widespread infection. In terms of surveillance, particular attention will be paid to the detection of mutations in the receptor-binding site of the H10 haemagglutinin that decrease its avidity for avian receptor, and could enable it to be more readily transmitted between humans.


Assuntos
Aves/virologia , Orthomyxoviridae/química , Orthomyxoviridae/metabolismo , Receptores Virais/química , Receptores Virais/metabolismo , Animais , Sítios de Ligação , Cristalografia por Raios X , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Vírus da Influenza A Subtipo H1N1/química , Subtipo H7N9 do Vírus da Influenza A/química , Modelos Moleculares , Zoonoses/transmissão , Zoonoses/virologia
17.
J Neurosci ; 38(4): 937-961, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29229708

RESUMO

There is an ongoing debate on the contribution of the neuronal glutamate transporter EAAC1 to the onset of compulsive behaviors. Here, we used behavioral, electrophysiological, molecular, and viral approaches in male and female mice to identify the molecular and cellular mechanisms by which EAAC1 controls the execution of repeated motor behaviors. Our findings show that, in the striatum, a brain region implicated with movement execution, EAAC1 limits group I metabotropic glutamate receptor (mGluRI) activation, facilitates D1 dopamine receptor (D1R) expression, and ensures long-term synaptic plasticity. Blocking mGluRI in slices from mice lacking EAAC1 restores D1R expression and synaptic plasticity. Conversely, activation of intracellular signaling pathways coupled to mGluRI in D1R-containing striatal neurons of mice expressing EAAC1 leads to reduced D1R protein level and increased stereotyped movement execution. These findings identify new molecular mechanisms by which EAAC1 can shape glutamatergic and dopaminergic signals and control repeated movement execution.SIGNIFICANCE STATEMENT Genetic studies implicate Slc1a1, a gene encoding the neuronal glutamate transporter EAAC1, with obsessive-compulsive disorder (OCD). EAAC1 is abundantly expressed in the striatum, a brain region that is hyperactive in OCD. What remains unknown is how EAAC1 shapes synaptic function in the striatum. Our findings show that EAAC1 limits activation of metabotropic glutamate receptors (mGluRIs) in the striatum and, by doing so, promotes D1 dopamine receptor (D1R) expression. Targeted activation of signaling cascades coupled to mGluRIs in mice expressing EAAC1 reduces D1R expression and triggers repeated motor behaviors. These findings provide new information on the molecular basis of OCD and suggest new avenues for its treatment.


Assuntos
Comportamento Compulsivo/metabolismo , Corpo Estriado/metabolismo , Transportador 3 de Aminoácido Excitatório/metabolismo , Plasticidade Neuronal/fisiologia , Receptores de Glutamato Metabotrópico/metabolismo , Animais , Comportamento Compulsivo/fisiopatologia , Dopamina/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Dopamina D1/metabolismo , Transdução de Sinais/fisiologia
18.
Emerg Infect Dis ; 25(3): 607-609, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30789339

RESUMO

We report 3 cases of influenza C virus in children hospitalized with severe acute respiratory infection in Cameroon. Two of these case-patients had grave clinical manifestations, but all 3 recovered. The lack of specific antiviral drugs for influenza C virus highlights the need to identify and describe cases involving this virus.


Assuntos
Gammainfluenzavirus/genética , Hospitalização , Influenza Humana/epidemiologia , Influenza Humana/virologia , Camarões/epidemiologia , Pré-Escolar , Genes Virais , Genoma Viral , Humanos , Lactente , Influenza Humana/diagnóstico , Gammainfluenzavirus/classificação , Filogenia , Vigilância da População
19.
J Gen Virol ; 100(7): 1079-1092, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31169484

RESUMO

Candidate vaccine viruses (CVVs) for seasonal influenza A virus are made by reassortment of the antigenic virus with an egg-adapted strain, typically A/Puerto Rico/8/34 (PR8). Many 2009 A(H1N1) pandemic (pdm09) high-growth reassortants (HGRs) selected this way contain pdm09 segment 2 in addition to the antigenic genes. To investigate this, we made CVV mimics by reverse genetics (RG) that were either 6 : 2 or 5 : 3 reassortants between PR8 and two pdm09 strains, A/California/7/2009 (Cal7) and A/England/195/2009, differing in the source of segment 2. The 5 : 3 viruses replicated better in MDCK-SIAT1 cells than the 6 : 2 viruses, but the 6 : 2 CVVs gave higher haemagglutinin (HA) antigen yields from eggs. This unexpected phenomenon reflected temperature sensitivity conferred by pdm09 segment 2, as the egg HA yields of the 5 : 3 viruses improved substantially when viruses were grown at 35 °C compared with 37.5 °C, whereas the 6 : 2 virus yields did not. However, the authentic 5 : 3 pdm09 HGRs, X-179A and X-181, were not markedly temperature sensitive despite their PB1 sequences being identical to that of Cal7, suggesting compensatory mutations elsewhere in the genome. Sequence comparisons of the PR8-derived backbone genes identified polymorphisms in PB2, NP, NS1 and NS2. Of these, PB2 N701D affected the temperature dependence of viral transcription and, furthermore, improved and drastically reduced the temperature sensitivity of the HA yield from the 5 : 3 CVV mimic. We conclude that the HA yield of pdm09 CVVs can be affected by an epistatic interaction between PR8 PB2 and pdm09 PB1, but that this can be minimized by ensuring that the backbones used for vaccine manufacture in eggs contain PB2 701D.


Assuntos
Epistasia Genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Influenza Humana/virologia , Proteínas Virais/genética , Animais , Embrião de Galinha , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/metabolismo , Vacinas contra Influenza/genética , Vacinas contra Influenza/metabolismo , Vírus Reordenados/genética , Vírus Reordenados/crescimento & desenvolvimento , Vírus Reordenados/metabolismo , Temperatura , Proteínas Virais/metabolismo
20.
PLoS Pathog ; 13(12): e1006749, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29284042

RESUMO

The global-scale epidemiology and genome-wide evolutionary dynamics of influenza B remain poorly understood compared with influenza A viruses. We compiled a spatio-temporally comprehensive dataset of influenza B viruses, comprising over 2,500 genomes sampled worldwide between 1987 and 2015, including 382 newly-sequenced genomes that fill substantial gaps in previous molecular surveillance studies. Our contributed data increase the number of available influenza B virus genomes in Europe, Africa and Central Asia, improving the global context to study influenza B viruses. We reveal Yamagata-lineage diversity results from co-circulation of two antigenically-distinct groups that also segregate genetically across the entire genome, without evidence of intra-lineage reassortment. In contrast, Victoria-lineage diversity stems from geographic segregation of different genetic clades, with variability in the degree of geographic spread among clades. Differences between the lineages are reflected in their antigenic dynamics, as Yamagata-lineage viruses show alternating dominance between antigenic groups, while Victoria-lineage viruses show antigenic drift of a single lineage. Structural mapping of amino acid substitutions on trunk branches of influenza B gene phylogenies further supports these antigenic differences and highlights two potential mechanisms of adaptation for polymerase activity. Our study provides new insights into the epidemiological and molecular processes shaping influenza B virus evolution globally.


Assuntos
Vírus da Influenza B/genética , Influenza Humana/epidemiologia , Influenza Humana/virologia , Substituição de Aminoácidos , Variação Antigênica , Antígenos Virais/genética , Bases de Dados Genéticas , Evolução Molecular , Variação Genética , Genoma Viral , Saúde Global , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza B/classificação , Vírus da Influenza B/imunologia , Modelos Moleculares , Epidemiologia Molecular , Filogenia , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/genética , Vírus Reordenados/genética , Proteínas Virais/química , Proteínas Virais/genética
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