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1.
Biopreserv Biobank ; 18(6): 561-569, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33181021

RESUMO

When a new virus emerges and causes a significant epidemic, the emergency response relies on diagnostics, surveillance, testing, and proposal of treatments if they exist, and also in the longer term, redirection of research efforts toward understanding the newly discovered pathogen. To serve these goals, viral biobanks play a crucial role. The European Virus Archive (EVA) is a network of biobanks from research laboratories worldwide that has combined into a common set of practices and mutually beneficial objectives to give scientists the tools that they need to study viruses in general, and also to respond to a pandemic caused by emerging viruses. Taking the most recent outbreaks of the Zika virus and SARS-CoV-2 as examples, by looking at who orders what and when to the EVA, we illustrate how the global science community at large, public health, fundamental research and private companies, reorganize their activity toward diagnosing, understanding, and fighting the new pathogen.


Assuntos
Bancos de Espécimes Biológicos , COVID-19 , Pandemias , SARS-CoV-2/metabolismo , Infecção por Zika virus , Zika virus/metabolismo , COVID-19/epidemiologia , COVID-19/metabolismo , Europa (Continente)/epidemiologia , Humanos , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-28131384

RESUMO

West Nile fever (WNF) is a viral disease of wild birds transmitted by mosquitoes. Humans and equids can also be affected and suffer from meningoencephalitis. In Algeria, since the 1994 epidemic, no data on WNV circulation was available until 2012. In September 2012, a fatal human case of WNV neuro-invasive infection occurred in Jijel province. This study describes the first seroprevalence study of West Nile virus (WNV) antibodies conducted in the equine population in Algeria. During 2014, serum samples were collected from 293 equids (222 donkeys and 71 horses) asymptomatic and unvaccinated for WNV in three localities in Northeastern wetlands of Algeria. Antibodies against WNV were found in 51 samples (seroprevalence 17.4%) of sampled equids, distributed as follows: 19 (seroprevalence 26.8%) horses and 32 (seroprevalence 14.4%) donkeys. Moreover 7 horses coming from Blida, in the center of Algeria, were tested before and after an 8-months stay in North-East Algeria. We observe a seroconversion in 2 horses, showing WNV circulation in 2014 in this specific region of Algeria.


Assuntos
Anticorpos Antivirais/sangue , Equidae , Doenças dos Cavalos/imunologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/isolamento & purificação , Argélia/epidemiologia , Animais , Animais Selvagens/imunologia , Animais Selvagens/virologia , Doenças Assintomáticas/epidemiologia , Culicidae/virologia , Ensaio de Imunoadsorção Enzimática/veterinária , Equidae/imunologia , Cavalos/imunologia , Humanos , Soroconversão , Estudos Soroepidemiológicos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/imunologia , Febre do Nilo Ocidental/virologia , Áreas Alagadas
4.
Emerg Infect Dis ; 20(12): 2129-32, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25418184

RESUMO

Chikungunya virus (CHIKV) is present or emerging in dengue virus-endemic areas. Infections caused by these viruses share some common signs/symptoms, but prognosis, patient care, and persistent symptoms differ. Thus, accurate diagnostic methods are essential for differentiating the infections. We evaluated 4 CHIKV serologic diagnostic tests, 2 of which showed poor sensitivity and specificity.


Assuntos
Febre de Chikungunya/diagnóstico , Vírus Chikungunya/classificação , Kit de Reagentes para Diagnóstico , Testes Sorológicos/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Testes Sorológicos/normas
5.
Arch Virol ; 155(5): 789-93, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20333534

RESUMO

Mutational analysis of the phosphate acceptor sites of the Borna disease virus (BDV) phosphoprotein (P) has suggested a role of phosphorylation for viral spread. However, the studied mutant viruses also had two amino acid exchanges in the X protein, because the reading frames of P and X overlap. To determine the relative contribution of P and X to viral attenuation, we studied a P variant with serine-to-leucine substitutions (P(S26L,S28L)) in which the wild-type X sequence was conserved. Viral spread of rBDV-P(S26L,S28L) was impaired in human oligodendroglioma cells and in adult rats. Thus, BDV-P phosphorylation contributes to efficient viral dissemination.


Assuntos
Vírus da Doença de Borna/fisiologia , Fosfoproteínas/metabolismo , Proteína Quinase C/fisiologia , Proteínas Estruturais Virais/metabolismo , Animais , Células Cultivadas , Humanos , Fosforilação , Proteína Quinase C/química , Ratos , Ratos Endogâmicos Lew
6.
PLoS Pathog ; 5(5): e1000425, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19424436

RESUMO

Understanding the pathogenesis of infection by neurotropic viruses represents a major challenge and may improve our knowledge of many human neurological diseases for which viruses are thought to play a role. Borna disease virus (BDV) represents an attractive model system to analyze the molecular mechanisms whereby a virus can persist in the central nervous system (CNS) and lead to altered brain function, in the absence of overt cytolysis or inflammation. Recently, we showed that BDV selectively impairs neuronal plasticity through interfering with protein kinase C (PKC)-dependent signaling in neurons. Here, we tested the hypothesis that BDV phosphoprotein (P) may serve as a PKC decoy substrate when expressed in neurons, resulting in an interference with PKC-dependent signaling and impaired neuronal activity. By using a recombinant BDV with mutated PKC phosphorylation site on P, we demonstrate the central role of this protein in BDV pathogenesis. We first showed that the kinetics of dissemination of this recombinant virus was strongly delayed, suggesting that phosphorylation of P by PKC is required for optimal viral spread in neurons. Moreover, neurons infected with this mutant virus exhibited a normal pattern of phosphorylation of the PKC endogenous substrates MARCKS and SNAP-25. Finally, activity-dependent modulation of synaptic activity was restored, as assessed by measuring calcium dynamics in response to depolarization and the electrical properties of neuronal networks grown on microelectrode arrays. Therefore, preventing P phosphorylation by PKC abolishes viral interference with neuronal activity in response to stimulation. Our findings illustrate a novel example of viral interference with a differentiated neuronal function, mainly through competition with the PKC signaling pathway. In addition, we provide the first evidence that a viral protein can specifically interfere with stimulus-induced synaptic plasticity in neurons.


Assuntos
Vírus da Doença de Borna/fisiologia , Neurônios/virologia , Proteína Quinase C/genética , Sinapses/virologia , Transmissão Sináptica/fisiologia , Potenciais de Ação , Animais , Western Blotting , Doença de Borna/fisiopatologia , Células Cultivadas , Imunofluorescência , Mutação , Plasticidade Neuronal/fisiologia , Técnicas de Patch-Clamp , Fosfoproteínas , Fosforilação , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Proteínas Virais/genética , Proteínas Virais/metabolismo
7.
J Virol ; 81(16): 8833-7, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17553893

RESUMO

The mechanisms whereby Borna disease virus (BDV) can impair neuronal function and lead to neurobehavioral disease are not well understood. To analyze the electrophysiological properties of neurons infected with BDV, we used cultures of neurons grown on multielectrode arrays, allowing a real-time monitoring of the electrical activity across the network shaped by synaptic transmission. Although infection did not affect spontaneous neuronal activity, it selectively blocked activity-dependent enhancement of neuronal network activity, one form of synaptic plasticity thought to be important for learning and memory. These findings highlight the original mechanism of the neuronal dysfunction caused by noncytolytic infection with BDV.


Assuntos
Doença de Borna/fisiopatologia , Vírus da Doença de Borna , Córtex Cerebral/fisiopatologia , Plasticidade Neuronal , Sinapses/virologia , Animais , Córtex Cerebral/virologia , Eletrofisiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neurônios/virologia , Fosfoproteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Transmissão Sináptica , Proteínas Estruturais Virais/metabolismo
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