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1.
Trop Anim Health Prod ; 53(1): 90, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33415381

RESUMO

Circulation of the dominant sub-genotype VII.2 of Avian Orthoavulavirus-1 (AOAV-1) is affecting multiple poultry and non-poultry avian species and causing significant economic losses to the poultry industry worldwide. In countries where ND is endemic, continuous monitoring and characterization of field strains are necessary. In this study, genetic characteristics of eleven AOAV-1 strains were analyzed isolated from wild birds including parakeets (n = 3), lovebird parrot (n = 1), pheasant (n = 1), peacock (n = 1), and backyard chickens (n = 5) during 2015-2016. Genetic characterization (genome size [15,192 nucleotides], the presence of typical cleavage site [112-RRQKRF-117]) and biological assessment (HA log 27 to 29 and intracerebral pathogenicity index [ICPI] value ranging from 1.50 to 1.86) showed virulent AOAV-1. Phylogenetic analysis showed that the studied isolates belonged to sub-genotype VII.2 and genetically very closely related (> 98.9%) to viruses repeatedly isolated (2011-2018) from commercial poultry. These findings provide evidence for the existence of epidemiological links between poultry and wild bird species in the region where the disease is prevalent. The deduced amino acid analysis revealed several substitutions in critical domains of fusion and hemagglutinin-neuraminidase genes. The pathogenesis and transmission potential of wild bird-origin AOAV-1 strain (AW-Pht/2015) was evaluated in 21-day-old chickens that showed the strain was highly virulent causing clinical signs and killed all chickens. High viral loads were detected in different organs of the infected chickens correlating with the severity of lesions developed. The continuous monitoring of AOAV-1 isolates in different species of birds will improve our knowledge of the evolution of these viruses, thereby preventing possible panzootic.


Assuntos
Infecções por Avulavirus/veterinária , Avulavirus/fisiologia , Galinhas , Genoma Viral , Doenças das Aves Domésticas/virologia , Sequência de Aminoácidos , Animais , Animais Selvagens , Avulavirus/genética , Infecções por Avulavirus/virologia , Doenças das Aves/virologia , Galliformes , Paquistão , Papagaios , Proteínas Virais de Fusão/análise
2.
Iran Biomed J ; 24(2): 64-80, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31677609

RESUMO

Aging, as a major risk factor of memory deficiency, affects neural signaling pathways in hippocampus. In particular, age-dependent androgens deficiency causes cognitive impairments. Several enzymes like protein kinase C (PKC) are involved in memory deficiency. Indeed, PKC regulatory process mediates α-secretase activation to cleave APP in ß-amyloid cascade and tau proteins phosphorylation mechanism. Androgens and cortisol regulate PKC signaling pathways, affecting the modulation of receptor for activated C kinase 1. Mitogen-activated protein kinase/ERK signaling pathway depends on CREB activity in hippocampal neurons and is involved in regulatory processes via PKC and androgens. Therefore, testosterone and PKC contribute in the neuronal apoptosis. The present review summarizes the current status of androgens, PKC, and their influence on cognitive learning. Inconsistencies in experimental investigations related to this fundamental correlation are also discussed, with emphasis on the mentioned contributors as the probable potent candidates for learning and memory improvement.


Assuntos
Doença de Alzheimer/patologia , Androgênios/metabolismo , Disfunção Cognitiva/patologia , Hipocampo/metabolismo , Proteína Quinase C/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Doença de Alzheimer/terapia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Cognição/fisiologia , Disfunção Cognitiva/terapia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Humanos , Aprendizagem/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Fosforilação , Receptores de Quinase C Ativada/metabolismo , Proteínas tau/metabolismo
3.
Arch Virol ; 164(3): 717-724, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30612199

RESUMO

Adaptation and evolution of avian avulavirus 1, or Newcastle disease virus (NDV), has led to tremendous economic losses worldwide. The occurrence of natural recombination and selection pressure has been traced for NDV based on a few recent reports, but a dominant pattern based on genomic characteristics is lacking. Here, we used bioinformatics tools to search for evidence of recombination in all of the available complete genome sequence of NDV (462 sequences) using RDP4 software. Geographical linkage and host cell relationships of recombinant viruses were also investigated, and a study of the adaptive evolution of avian avulavirus 1 was performed. The results revealed that recombination events could occur in any gene fragment of the NDV genome. Moreover, class I NDV isolates from wild birds could associate to generate a putative recombinant virus with a class II genome backbone. In addition, not only avirulent-virulent hybrid genotypes but also virulent-virulent natural recombinant NDV viruses were generated. Investigation of geographic relationships of recombinant isolates indicated that the highest rate of recombination occurs in Asia and the Middle East, which can be influenced by vaccination failure, evasion of the immune response, live-bird markets, and the bird trade. The M and NP genes were found to have higher negative selection rates than the other genes, which might lead to the deletion of inadaptable sequences and result in more conserved sequences. Based on our analysis, the highest rate of positive selection was observed in the L, F and HN genes, which we suggest could lead to the occurrence of evolved viruses with high pathogenicity and a better chance of survival under extreme conditions.


Assuntos
Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Doenças das Aves Domésticas/virologia , Recombinação Genética , Animais , Animais Selvagens/virologia , Ásia , Aves/virologia , Galinhas , Evolução Molecular , Genoma Viral , Oriente Médio , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/isolamento & purificação , Vírus da Doença de Newcastle/fisiologia , Filogenia , Proteínas Virais/genética
4.
Indian J Microbiol ; 58(3): 326-331, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30013277

RESUMO

Hemagglutinin-neuraminidase (HN) protein besides its mediation in viral pathogenesis, is composed of various antigenic sites which stimulate production of host's antibodies. Thus, application of this protein in serological tests and vaccination plays a major role in biosecurity and control programs. In the present study, we designed a recombinant HN protein containing different neutralizing antigenic sites with velogenic patterns, and sub-cloned it into pET-43.1a+ expression vector. The expression of NusA-HN recombinant protein was induced. Affinity chromatography protein purification using HisPur™ Ni-NTA was then conducted. Moreover, we performed western-blot technique using HRP-conjugated Anti His-Tag. Results revealed that following induction of recombinant protein, two distinct bands of HN-61 kDa and NusA-63 kDa were purified and identified by western-blotting. We recommend further analysis should be carried out to determine the functional role of this recombinant protein in enzyme-linked immunosorbent assays for Newcastle disease diagnosis. This HN protein containing multi neutralizing antigenic sites might also be applicable in vaccination programs to increase vaccines potency.

5.
Arch Virol ; 162(12): 3727-3743, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28864876

RESUMO

In the case of Newcastle disease virus, multiple factors such as host adaptation, immune response evasion, and selective pressures have been suggested to result in evolution of viruses and the emergence of genetic variants. Multiple studies on virus classification and global epidemiological links have yielded consistent data. Here, we have performed a molecular analysis study of circulating Newcastle disease viruses in Iran (1995-2016). According to evolutionary divergences, subgenotype VIg, VIj, VIIj, VIId, XIIIa and XIIId isolates have been circulating in the country during a 21-year period. Based on data analysis, VIg isolates shared highest sequence identity with Russian and Polish isolates of the VIg subgenotype, while VIj subgenotype isolates (2012) were most similar to a virus isolated in 2015 in India. Analysis of the evolutionary divergence of subgenotype VIIj suggests that Chinese and Ukrainian viruses may have played a crucial role in the emergence of VIIj isolates. Evolutionary difference studies also indicated that XIIIa isolates circulating in Iran may have caused the emergence of adapted variants of subgenotype XIIId. Therefore, we propose that the evolutionary and epidemiological study of virulent Newcastle disease viruses could help to provide accurate molecular data about variants circulating in the region, thus aiding in the design of more efficient recombinant vaccines.


Assuntos
Evolução Molecular , Variação Genética , Doença de Newcastle/epidemiologia , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/genética , Aves Domésticas , Animais , Genótipo , Irã (Geográfico)/epidemiologia , Epidemiologia Molecular , Vírus da Doença de Newcastle/isolamento & purificação , Filogenia , Homologia de Sequência
6.
Arch Virol ; 162(4): 971-978, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28004254

RESUMO

Newcastle disease virus (NDV) is believed to be the cause of fatal poultry disease worldwide. The fusion (F) protein plays a key role in virus pathogenesis, and it is also used for Newcastle disease virus classification. In this study, we determined the complete coding sequence of the F gene in new velogenic NDV isolates with an intravenous pathogenicity index (IVPI) of 1.8 and a mean death time (MDT) of 72 or 48 h. Complete sequences of the F genes of new Iranian isolates were amplified and sequenced in both directions. These isolates were compared to 195 nucleotide sequences from GenBank (available as of 07/17/2016). A phylogenetic tree was constructed for the F gene, using MEGA6 software with statistical analysis based on 500 bootstrap replicates. Evolutionary distances revealed that the new virulent isolates from Iran belonged to genotype VII in a new distinct sub-genotype named VII-(j). This new sub-genotype showed 3% divergence from genotype VIId. Recombination analysis showed that these new isolates were not recombinant NDVs.


Assuntos
Doença de Newcastle/virologia , Vírus da Doença de Newcastle/isolamento & purificação , Doenças das Aves Domésticas/virologia , Proteínas Virais de Fusão/genética , Animais , Galinhas , Genótipo , Irã (Geográfico) , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/genética , Filogenia
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