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1.
J Med Virol ; 92(12): 3179-3186, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31696948

RESUMO

Multiple Rotavirus A (RVA) strains are linked with gastrointestinal infections in children that fall in age bracket of 0 to 60 months. However, the problem is augmented with emergence of unique strains that reassort with RVA strains of animal origin. The study describes the sequence analysis of a rare G6P[1] rotavirus strain isolated from a less than 1 year old child, during rotavirus surveillance in Rawalpindi district, Pakistan in 2010. Extracted RNA from fecal specimen was subjected to high throughput RT-PCR for structural and nonstructural gene segments. The complete rotavirus genome of one isolate RVA/Human-wt/PAK/PAK99/2010/G6P[1] was sequenced for phylogenetic analysis to elucidate the evolutionary linkages and origin. Full genome examination of novel strain RVA/Human-wt/PAK/PAK99/2010/G6P[1] revealed the unique genotype assemblage: G6-P[1]-I2-R2-C2-M2-A3-N2-T6-E2-H1. The evolutionary analyses of VP7, VP4, NSP1 and NSP3 gene segments revealed that PAK99 clustered with bovine, or cattle-like rotavirus strains from other closely related species, in the genotypes G6, P[1], A3 and T6 respectively. Gene segments VP6, VP1, VP2, VP3, NSP2 and NSP4 all possessed the DS-1-like bovine genotype 2 and bovine (-like) RVA strains instead of RVA strains having human origin. However, the NSP5 gene was found to cluster closely with contemporary human Wa-like rotavirus strains of H1 genotype. This is the first report on bovine-human (Wa-like reassortant) genotype constellation of G6P[1] strain from a human case in Pakistan (and the second description worldwide). Our results emphasize the significance of incessant monitoring of circulating RVA strains in humans and animals for better understanding of RV evolution.

2.
Arch Virol ; 164(7): 1781-1791, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31079214

RESUMO

Introduction of animal group A rotavirus (RVA) gene segments into the human RVA population is a major factor shaping the genetic landscape of human RVA strains. The VP6 and NSP4 genes of 74 G/P-genotyped RVA isolates collected in Rawalpindi during 2010 were analyzed, revealing the presence of VP6 genotypes I1 (60.8%) and I2 (39.2%) and NSP4 genotypes E1 (60.8%), E2 (28.3%) and E-untypable (10.8%) among the circulating human RVA strains. The typical human RVA combinations I1E1 and I2E2 were found in 59.4% and 24.3% of the cases, respectively, whereas 5.4% of the RVA strains were reassortants, i.e., either I1E2 or I2E1. The phylogeny of the NSP4 gene showed that one G2P[4] and two G1P[6] RVA strains clustered with porcine E1 RVA strains or RVA strains that were considered to be (partially) of porcine origin. In addition, the NSP4 gene segment of the unusual human G6P[1] RVA strains clustered closely with bovine E2 RVA strains, further strengthening the hypothesis of an interspecies transmission event. The study further demonstrates the role of genomic re-assortment and the involvement of interspecies transmission in the evolution of human RVA strains. The VP6 and NSP4 nucleotide sequences analyzed in the study received the GenBank accession numbers KC846908- KC846971 and KC846972-KC847037, respectively.


Assuntos
Antígenos Virais/genética , Proteínas do Capsídeo/genética , Glicoproteínas/genética , Infecções por Rotavirus/transmissão , Rotavirus/genética , Rotavirus/isolamento & purificação , Toxinas Biológicas/genética , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Animais , Bovinos , Pré-Escolar , Gastroenterite/virologia , Genoma Viral/genética , Genótipo , Humanos , Paquistão , Filogenia , Infecções por Rotavirus/virologia , Alinhamento de Sequência , Suínos , Zoonoses/virologia
3.
Mol Biol Evol ; 32(8): 2060-71, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25858434

RESUMO

The majority of human group A rotaviruses possess the P[8] VP4 genotype. Recently, a genetically distinct subtype of the P[8] genotype, also known as OP354-like P[8] or lineage P[8]-4, emerged in several countries. However, it is unclear for how long the OP354-like P[8] gene has been circulating in humans and how it has spread. In a global collaborative effort 98 (near-)complete OP354-like P[8] VP4 sequences were obtained and used for phylogeographic analysis to determine the viral migration patterns. During the sampling period, 1988-2012, we found that South and East Asia acted as a source from which strains with the OP354-like P[8] gene were seeded to Africa, Europe, and North America. The time to the most recent common ancestor (TMRCA) of all OP354-like P[8] genes was estimated at 1987. However, most OP354-like P[8] strains were found in three main clusters with TMRCAs estimated between 1996 and 2001. The VP7 gene segment of OP354-like P[8] strains showed evidence of frequent reassortment, even in localized epidemics, suggesting that OP354-like P[8] genes behave in a similar manner on the evolutionary level as other P[8] subtypes. The results of this study suggest that OP354-like P[8] strains have been able to disperse globally in a relatively short time period. This, in combination with a relatively large genetic distance to other P[8] subtypes, might result in a lower vaccine effectiveness, underscoring the need for a continued surveillance of OP354-like P[8] strains, especially in countries where rotavirus vaccination programs are in place.


Assuntos
Genes Virais , Genótipo , Infecções por Rotavirus , Rotavirus , Ásia , Humanos , Filogeografia , Rotavirus/genética , Rotavirus/patogenicidade , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/genética , Infecções por Rotavirus/transmissão
5.
J Med Microbiol ; 73(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38757423

RESUMO

Introduction. Human immunodeficiency virus (HIV)-1 subtype C is the most prevalent globally and is thought to have originated in non-human primates in the Democratic Republic of Congo.Hypothesis/Gap Statement. Although the global dominance of HIV-1 subtype C is well established, a thorough understanding of its evolutionary history and transmission dynamics across various risk populations remains elusive. The current knowledge is insufficient to fully capture the global diversification and dissemination of this subtype.Aim. We for the first time sought to investigate the global evolutionary history and spatiotemporal dynamics of HIV-1 subtype C using a selection of maximum-likelihood-based phylodynamic approaches on a total of 1210 near full-length genomic sequences sampled from 32 countries, collected in 4 continents, with sampling dates between 1986-2019 among various risk groups were analysed.Methodology. We subsampled the HIV-1 subtype C genomic datasets based on continent and risk group traits, and performed nucleotide substitution model selection analysis, maximum likelihood (ML) phylogenetic reconstruction, phylogenetic tree topology similarity analysis, temporal signal analysis and traced the timings of viral spread both geographically and by risk group.Results. Based on the phylodynamic analyses of four datasets (full1210, locrisk626, loc562 and risk393), we inferred the time to the most recent common ancestor (TMRCA) in the 1930s and an evolutionary rate of 0.0023 substitutions per site per year. The total number of introduction events of HIV-1 subtype C between continents and between risk groups is estimated to be 71 and 115, respectively. The largest number of introductions occurred from Africa to Europe (n=32), from not-recorded to heterosexual (n=40) and from heterosexual to not-recorded (n=51) risk groups.Conclusion. Our results emphasize that HIV subtype C has mainly spread from Africa to Europe, likely through heterosexual transmission.


Assuntos
Infecções por HIV , HIV-1 , Filogenia , HIV-1/genética , HIV-1/classificação , HIV-1/isolamento & purificação , Humanos , Infecções por HIV/virologia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Evolução Molecular
6.
Appl Biosaf ; 27(1): 33-41, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36032320

RESUMO

Introduction: Healthcare organizations are complex systems where healthcare professionals, patients, biological materials, and equipment constantly interact and provide feedback with highly consequential outcomes. These are the characteristics of a complex adaptive system. Healthcare delivery requires coordination but it necessarily relies on delegation of essential functions. It is thus essential to have an engaged workforce to ensure optimal outcomes for patients. Thus human performance factors play a key role in ensuring both the presence of excellent healthcare provision and the absence of outcomes that must be avoided-"never events." Methods: The commitment of management was a precondition for the implementation of the high-reliability organization (HRO) principles. A team from middle management was engaged and provided with appropriate management tools for identifying, prioritizing, assessing, and applying solutions for the safety concern in their operating systems. Results: This article documents efforts at the National Institute of Health (NIH) to adapt the principles of HROs to diagnostic laboratories and vaccine production facilities at its campus in Islamabad, Pakistan, and seeks to draw some lessons for how this approach can be usefully replicated in such facilities elsewhere. Conclusion: Public health institutes such as NIH deliver vital products and services that are inherently risky to produce, where the consequence of failure can be catastrophic. Adopting the HRO principles is an approach to improving not just safety, but also the overall organizational performance in any setting, including low-resource settings, and can serve as an implementable process for other institutions.

7.
Infect Genet Evol ; 94: 105003, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34271187

RESUMO

Genomic epidemiology of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has provided global epidemiological insight into the COVID-19 pandemic since it began. Sequencing of the virus has been performed at scale, with many countries depositing data into open access repositories to enable in-depth global phylogenetic analysis. To contribute to these efforts, we established an Oxford Nanopore Technologies (ONT) sequencing capability at the National Institutes of Health (NIH), Pakistan. This study highlights multiple SARS-CoV-2 lineages co-circulating during the peak of a second COVID-19 wave in Pakistan (Nov 2020-Feb 2021), with virus origins traced to the United States of America and Saudi Arabia. Ten SARS-CoV-2 positive samples were used for ONT library preparation. Sequence and phylogenetic analysis determined that the patients were infected with lineage B.1.1.250, originally identified in the United Kingdom and Bangladesh during March and April of 2020, and in circulation until the time of this study in Europe, USA and Australia. Lineage B.1.261 was originally identified in Saudi Arabia with widespread local dissemination in Pakistan. One sample clustered with the parental B.1 lineage and the other with lineage B.6 originally from Singapore. In the future, monitoring the evolutionary dynamics of circulating lineages in Pakistan will enable improved tracing of the viral spread, changing trends of their expansion trajectories, persistence, changes in their demographic dynamics, and provide guidance for better implementation of control measures.


Assuntos
COVID-19/virologia , SARS-CoV-2/isolamento & purificação , COVID-19/diagnóstico , COVID-19/epidemiologia , Humanos , Nasofaringe/virologia , Paquistão/epidemiologia , Pandemias , Filogenia , RNA Viral/genética , SARS-CoV-2/classificação , SARS-CoV-2/genética , Sequenciamento Completo do Genoma
8.
PLoS One ; 16(6): e0249568, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34185787

RESUMO

The ongoing COVID-19 pandemic is caused by SARs-CoV-2. The virus is transmitted from person to person through droplet infections i.e. when infected person is in close contact with another person. In January 2020, first report of detection of SARS-CoV-2 in faeces, has made it clear that human wastewater might contain this virus. This may illustrate the probability of environmentally facilitated transmission, mainly the sewage, however, environmental conditions that could facilitate faecal oral transmission is not yet clear. We used existing Pakistan polio environment surveillance network to investigate presence of SARs-CoV-2 using three commercially available kits and E-Gene detection published assay for surety and confirmatory of positivity. A Two-phase separation method is used for sample clarification and concentration. An additional high-speed centrifugation (14000Xg for 30 min) step was introduced, prior RNA extraction, to increase viral RNA yield resulting a decrease in Cq value. A total of 78 wastewater samples collected from 38 districts across Pakistan, 74 wastewater samples from existing polio environment surveillance sites, 3 from drains of COVID-19 infected areas and 1 from COVID 19 quarantine center drainage, were tested for presence of SARs-CoV-2. 21 wastewater samples (27%) from 13 districts turned to be positive on RT-qPCR. SARs-COV-2 RNA positive samples from areas with COVID 19 patients and quarantine center strengthen the findings and use of wastewater surveillance in future. Furthermore, sequence data of partial ORF 1a generated from COVID 19 patient quarantine center drainage sample also reinforce our findings that SARs-CoV-2 can be detected in wastewater. This study finding indicates that SARs-CoV-2 detection through wastewater surveillance has an epidemiologic potential that can be used as supplementary system to monitor viral tracking and circulation in cities with lower COVID-19 testing capacity or heavily populated areas where door-to-door tracing may not be possible. However, attention is needed on virus concentration and detection assay to increase the sensitivity. Development of highly sensitive assay will be an indicator for virus monitoring and to provide early warning signs.


Assuntos
Monitoramento Ambiental , RNA Viral/análise , SARS-CoV-2/genética , Águas Residuárias/virologia , COVID-19/patologia , COVID-19/transmissão , COVID-19/virologia , Humanos , Paquistão , Poliproteínas/genética , Quarentena , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2/isolamento & purificação , Proteínas Virais/genética
9.
PeerJ ; 5: e2733, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28070453

RESUMO

G1P[8] rotaviruses are responsible for the majority of human rotavirus infections worldwide. The effect of universal mass vaccination with rotavirus vaccines on circulating G1P[8] rotaviruses is still poorly understood. Therefore we analyzed the complete genomes of the Rotarix™ vaccine strain, and 70 G1P[8] rotaviruses, detected between 1999 and 2010 in Belgium (36 before and 34 after vaccine introduction) to investigate the impact of rotavirus vaccine introduction on circulating G1P[8] strains. All rotaviruses possessed a complete Wa-like genotype constellation, but frequent intra-genogroup reassortments were observed as well as multiple different cluster constellations circulating in a single season. In addition, identical cluster constellations were found to circulate persistently over multiple seasons. The Rotarix™ vaccine strain possessed a unique cluster constellation that was not present in currently circulating G1P[8] strains. At the nucleotide level, the VP6, VP2 and NSP2 gene segments of Rotarix™ were relatively distantly related to any Belgian G1P[8] strain, but other gene segments of Rotarix™ were found in clusters also containing circulating Belgian strains. At the amino acid level, the genetic distance between Rotarix™ and circulating Belgian strains was considerably lower, except for NSP1. When we compared the Belgian G1P[8] strains collected before and after vaccine introduction a reduction in the proportion of strains that were found in the same cluster as the Rotarix™ vaccine strain was observed for most gene segments. The reduction in the proportion of strains belonging to the same cluster may be the result of the vaccine introduction, although natural fluctuations cannot be ruled out.

10.
J Hum Genet ; 53(2): 101-105, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18084694

RESUMO

Hereditary hearing impairment (HI) displays extensive genetic heterogeneity. To date, 67 autosomal recessive nonsyndromic hearing impairment (ARNSHI) loci have been mapped, and 24 genes have been identified. This report describes three large consanguineous ARNSHI Pakistani families, all of which display linkage to marker loci located in the genetic interval of DFNB49 locus on chromosome 5q13. Recently, Riazuddin et al. (Am J Hum Genet 2006; 79:1040-1051) reported that variants within the TRIC gene, which encodes tricellulin, are responsible for HI due to DFNB49. TRIC gene sequencing in these three families led to the identification of a novel mutation (IVS4+1G> A) in one family and the discovery of a previously described mutation (IVS4+2T> C) in two families. It is estimated that 1.06% (95% confidence interval 0.02-3.06%) of families with ARNSHI in Pakistan manifest HI due to mutations in the TRIC gene.


Assuntos
Genes Recessivos/genética , Perda Auditiva/genética , Proteínas de Membrana/genética , Mutação/genética , Sítios de Splice de RNA/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 2/genética , Consanguinidade , Análise Mutacional de DNA , Feminino , Ligação Genética , Genótipo , Humanos , Escore Lod , Proteína 2 com Domínio MARVEL , Masculino , Paquistão , Linhagem , Reação em Cadeia da Polimerase , Junções Íntimas
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