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1.
Exp Parasitol ; 221: 108051, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33301754

RESUMO

This study aimed to evaluate the efficacy of methanolic extract of P. longum (PLM) against protoscolices of hydatid cyst in vitro. Four different concentrations of PLM extract (25, 50, 100 and 150 mg/ml) were used for the experiments. The metabolites in the PLM extract were characterized by Gas chromatography-mass spectrometry (GC-MS). The results showed the highest lethality of PLM extract in 50 mg/ml for 60 min exposure. The IC50 value obtained about 20 mg/ml for 60 min of PLM extract exposure. In this study, valuable findings were obtained for the first time about the scolicidal activity of P. longum, which is expected to conduct further studies in this field in the future.


Assuntos
Equinococose/tratamento farmacológico , Echinococcus granulosus/efeitos dos fármacos , Piper/química , Extratos Vegetais/uso terapêutico , Alcaloides/análise , Animais , Equinococose/parasitologia , Flavonoides/análise , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Glicosídeos/análise , Cabras , Concentração Inibidora 50 , Fígado/parasitologia , Microscopia Eletrônica de Varredura , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Saponinas/análise , Ovinos , Taninos/análise , Terpenos/análise
2.
Sci Rep ; 10(1): 8441, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439885

RESUMO

Avian influenza viruses (AIV) are negative sense RNA viruses posing a major threat to the poultry industry worldwide, with the potential to spread to mammals, including humans; hence, an accurate and rapid AIV diagnosis is essential. To date AIV detection relies on molecular methods, mainly RT-qPCR directed against AIV M gene segment. The evolution of AIV represents a relevant issue in diagnostic RT-qPCR due to possible mispriming and/or probe-binding failures resulting in false negative results. Consequently, RT-qPCR for AIV detection should be periodically re-assessed both in silico and in vitro. To this end, a specific workflow was developed to evaluate in silico the complementarity of primers and probes of four published RT-qPCR protocols to their target regions. The four assays and one commercially available kit for AIV detection were evaluated both for their analytical sensitivity using eight different viral dilution panels and for their diagnostic performances against clinical specimens of known infectious status. Differences were observed among the tests under evaluation, both in terms of analytical sensitivity and of diagnostic performances. This finding confirms the importance of continuously monitoring the primers and probes complementarity to their binding regions.


Assuntos
Simulação por Computador , Variação Genética , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Aviária/diagnóstico , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Proteínas Virais/genética , Animais , Aves , Técnicas In Vitro , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/genética , Influenza Aviária/virologia , RNA Viral/genética , Curva ROC
3.
Infect Genet Evol ; 83: 104342, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32348876

RESUMO

Since 2005, H5Nx highly pathogenic avian influenza (HPAI) viruses of the Goose/Guangdong (Gs/GD) lineage have spread worldwide, affecting poultry and wild birds in Asia, Europe, Africa and North America. So far, the role of Western Asia and the Middle East in the diffusion dynamics of this virus has been poorly explored. In order to investigate the genetic diversity and the role of Iran in the transmission dynamics of the Gs/GD lineage, we sequenced the complete genome of twenty-eight H5Nx viruses which were circulating in the country between 2016 and 2018. We reported the first characterization of the HPAI H5N6 subtype of clade 2.3.4.4B in Iran and gave evidence of the high propensity of the Gs/GD H5 AIVs to reassort, describing six novel H5N8 genotypes of clade 2.3.4.4B, some of them likely generated in this area, and one H5N1 reassortant virus of clade 2.3.2.1c. Our spatial analyses demonstrated that the viruses resulted from different viral introductions from Asia and Europe and provided evidence of virus spread from Iran to the Middle East. Therefore, Iran may represent a hot-spot for virus introduction, dissemination and for the generation of new genetic variability. Increasing surveillance efforts in this high-risk area is of utmost importance for the early detection of novel emerging strains with zoonotic potential.


Assuntos
Virus da Influenza A Subtipo H5N1/genética , Vírus da Influenza A Subtipo H5N8/genética , Vírus Reordenados/genética , Animais , Aves , Genótipo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Virus da Influenza A Subtipo H5N1/patogenicidade , Vírus da Influenza A Subtipo H5N8/patogenicidade , Influenza Aviária/virologia , Irã (Geográfico) , Filogenia , Filogeografia
4.
J Virol ; 85(16): 8413-21, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21680519

RESUMO

Avian influenza viruses of the H9N2 subtype have seriously affected the poultry industry of the Far and Middle East since the mid-1990s and are considered one of the most likely candidates to cause a new influenza pandemic in humans. To understand the genesis and epidemiology of these viruses, we investigated the spatial and evolutionary dynamics of complete genome sequences of H9N2 viruses circulating in nine Middle Eastern and Central Asian countries from 1998 to 2010. We identified four distinct and cocirculating groups (A, B, C, and D), each of which has undergone widespread inter- and intrasubtype reassortments, leading to the generation of viruses with unknown biological properties. Our analysis also suggested that eastern Asia served as the major source for H9N2 gene segments in the Middle East and Central Asia and that in this geographic region within-country evolution played a more important role in shaping viral genetic diversity than migration between countries. The genetic variability identified among the H9N2 viruses was associated with specific amino acid substitutions that are believed to result in increased transmissibility in mammals, as well as resistance to antiviral drugs. Our study highlights the need to constantly monitor the evolution of H9N2 viruses in poultry to better understand the potential risk to human health posed by these viruses.


Assuntos
Evolução Molecular , Variação Genética , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/virologia , Influenza Humana/virologia , Vírus Reordenados/genética , Substituição de Aminoácidos , Animais , Ásia Central , Sequência de Bases , Farmacorresistência Viral/genética , Humanos , Vírus da Influenza A Subtipo H9N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Aviária/epidemiologia , Influenza Humana/epidemiologia , Oriente Médio , Filogenia , Filogeografia , Aves Domésticas , Vírus Reordenados/efeitos dos fármacos , Vírus Reordenados/patogenicidade , Risco , Análise de Sequência de RNA
5.
Emerg Infect Dis ; 13(5): 713-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17553249

RESUMO

To better understand the ecology and epidemiology of the highly pathogenic avian influenza virus in its transcontinental spread, we sequenced and analyzed the complete genomes of 36 recent influenza A (H5N1) viruses collected from birds in Europe, northern Africa, and southeastern Asia. These sequences, among the first complete genomes of influenza (H5N1) viruses outside Asia, clearly depict the lineages now infecting wild and domestic birds in Europe and Africa and show the relationships among these isolates and other strains affecting both birds and humans. The isolates fall into 3 distinct lineages, 1 of which contains all known non-Asian isolates. This new Euro-African lineage, which was the cause of several recent (2006) fatal human infections in Egypt and Iraq, has been introduced at least 3 times into the European-African region and has split into 3 distinct, independently evolving sublineages. One isolate provides evidence that 2 of these sublineages have recently reassorted.


Assuntos
Aves/virologia , Evolução Molecular , Genes Virais/genética , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/genética , África do Norte/epidemiologia , Animais , Europa (Continente)/epidemiologia , Virus da Influenza A Subtipo H5N1/classificação , Influenza Aviária/classificação , Oriente Médio/epidemiologia , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia
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