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1.
Rev Med Virol ; 32(1): e2259, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34997676

RESUMO

Group A rotaviruses (RVAs) are the leading cause of gastroenteritis, causing 0.2 million deaths and several million hospitalisations globally each year. Four rotavirus vaccines (RotarixTM , RotaTeqTM , Rotavac® and ROTASIIL® ) have been pre-qualified by the World Health Organization (WHO), but the two newly pre-qualified vaccines (Rotavac® and ROTASIIL® ) are currently only in use in Palestine and India, respectively. In 2009, WHO strongly proposed that rotavirus vaccines be included in the routine vaccination schedule of all countries around the world. By the end of 2019, a total of 108 countries had administered rotavirus vaccines, and 10 countries have currently been approved by Gavi for the introduction of rotavirus vaccine in the near future. With 39% of global coverage, rotavirus vaccines have had a substantial effect on diarrhoeal morbidity and mortality in different geographical areas, although efficacy appears to be higher in high income settings. Due to the segmented RNA genome, the pattern of RVA genotypes in the human population is evolving through interspecies transmission and/or reassortment events for which the vaccine might be less effective in the future. However, despite the relative increase in some particular genotypes after rotavirus vaccine use, the overall efficacy of rotavirus mass vaccination worldwide has not been affected. Some of the challenges to improve the effect of current rotavirus vaccines can be solved in the future by new rotavirus vaccines and by vaccines currently in progress.


Assuntos
Gastroenterite , Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Variação Genética , Humanos , Lactente , Rotavirus/genética , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas Atenuadas/genética
2.
Rev Med Virol ; 29(4): e2041, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31050070

RESUMO

Bacteriophages or phages, being the most abundant entities on earth, represent a potential solution to a diverse range of problems. Phages are successful antibacterial agents whose use in therapeutics was hindered by the discovery of antibiotics. Eventually, because of the development and spread of antibiotic resistance among most bacterial species, interest in phage as therapeutic entities has returned, because their noninfectious nature to humans should make them safe for human nanomedicine. This review highlights the most recent advances and progress in phage therapy and bacterial hosts against which phage research is currently being conducted with respect to food, human, and marine pathogens. Bacterial immunity against phages and tactics of phage revenge to defeat bacterial defense systems are also summarized. We have also discussed approved phage-based products (whole phage-based products and phage proteins) and shed light on their influence on the eukaryotic host with respect to host safety and induction of immune response against phage preparations. Moreover, creation of phages with desirable qualities and their uses in cancer treatment, vaccine production, and other therapies are also reviewed to bring together evidence from the scientific literature about the potentials and possible utility of phage and phage encoded proteins in the field of therapeutics and industrial biotechnology.


Assuntos
Doenças Transmissíveis/terapia , Microbiologia de Alimentos , Inocuidade dos Alimentos/métodos , Terapia por Fagos/métodos , Animais , Bacteriófagos/imunologia , Bacteriófagos/patogenicidade , Doenças Transmissíveis/veterinária , Humanos , Nanomedicina/métodos , Nanomedicina/tendências , Terapia por Fagos/tendências , Proteínas Virais/imunologia
3.
BMC Infect Dis ; 19(1): 978, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752744

RESUMO

BACKGROUND: Acute diarrhea is a leading cause of morbidity and mortality in children particularly in developing countries of Asia and Africa. The present study was conducted to detect the two most important pathogens, rotavirus and Campylobacter Jejuni in children suffering with diarrhea in Rawalpindi and Islamabad, Pakistan in 2014. The clinical and epidemiological aspects of the disease were also investigated. METHODS: A total of 500 stool samples were collected from children presented with clinical signs and symptoms of acute diarrhea. The samples were initially screened for the presence of rotavirus A (RVA) via ELISA (Enzyme-linked immunosorbent assay) and RT-PCR (Reverse Transcriptase PCR) and then were analysed for C. jejuni by using species specific PCR assay. RESULTS: The detection rate of RVA was 26.4% (132/500) while, Campylobacter was detected in 52% (260/500) of samples with C. jejuni accounted for 48.2% (241/500) of all study cases. Co-infection of C. jejuni with RVA was identified in 21.8% of all cases. Children with RVA and C. jejuni co-infection showed a higher probability (p = 0.01) to be dehydrated. A significant association (p = 0.02) was found between C. jejuni positive status and fever in children. The median age of children with both RVA and C. jejuni infection was 6-11 months. The RVA detection rate was high in winter months of the year while, C. jejuni infections were documented high in summer over 1 year study period. CONCLUSIONS: The overall results have demonstrated the high prevalence of C. jejuni in Rawalpindi, Islamabad, Pakistan in 2014. The results of present study will not only help to calculate disease burden caused by C. jejuni and rotavirus but also will provide critical information to health authorities in planning public health care strategies against these pathogens.


Assuntos
Infecções por Campylobacter/microbiologia , Campylobacter jejuni/isolamento & purificação , Diarreia/microbiologia , Diarreia/virologia , Infecções por Rotavirus/virologia , Rotavirus/isolamento & purificação , Infecções por Campylobacter/epidemiologia , Campylobacter jejuni/classificação , Campylobacter jejuni/genética , Pré-Escolar , Cidades , Coinfecção/epidemiologia , Coinfecção/microbiologia , Coinfecção/virologia , Diarreia/epidemiologia , Fezes/microbiologia , Fezes/virologia , Feminino , Humanos , Lactente , Masculino , Paquistão/epidemiologia , Prevalência , Rotavirus/classificação , Rotavirus/genética , Infecções por Rotavirus/epidemiologia
4.
Rev Med Virol ; 28(6): e2003, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30156344

RESUMO

Since its discovery 40 years ago, rotavirus (RV) is considered to be a major cause of infant and childhood morbidity and mortality particularly in developing countries. Nearly every child in the world under 5 years of age is at the risk of RV infection. It is estimated that 90% of RV-associated mortalities occur in developing countries of Africa and Asia. Two live oral vaccines, RotaTeq (RV5, Merck) and Rotarix (RV1, GlaxoSmithKline) have been successfully deployed to scale down the disease burden in Europe and America, but they are less effective in Africa and Asia. In April 2009, the World Health Organization recommended the inclusion of RV vaccination in national immunization programs of all countries with great emphasis in developing countries. To date, 86 countries have included RV vaccines into their national immunization programs including 41 Global Alliance for Vaccines and Immunization eligible countries. The predominant RV genotypes circulating all over the world are G1P[8], G2P[4], G3P[8], G4P[8], and G9P[8], while G12[P6] and G12[P8] are emerging genotypes. On account of the segmented genome, RV shows an enormous genetic diversity that leads to the evolution of new genotypes that can influence the efficacy of current vaccines. The current need is for a global RV surveillance program to monitor the prevalence and antigenic variability of new genotypes to formulate future vaccine development planning. In this review, we will summarize the previous and recent insights into RV structure, classification, and epidemiology and current status of RV vaccination around the globe and will also cover the status of RV research and vaccine policy in Pakistan.


Assuntos
Surtos de Doenças , Transmissão de Doença Infecciosa/prevenção & controle , Variação Genética , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologia , Rotavirus/patogenicidade , Pré-Escolar , Genótipo , Saúde Global , Humanos , Programas de Imunização , Lactente , Recém-Nascido , Prevalência , Rotavirus/classificação , Rotavirus/genética , Rotavirus/imunologia , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus/isolamento & purificação , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/isolamento & purificação
5.
Rev Med Virol ; 27(1)2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27597296

RESUMO

Dengue fever is regarded as one of the most prominent emerging arboviral infections in Pakistan since its first epidemic almost 2 decades ago. Interplay between potential vectors, susceptible host, and lax environmental conditions may promote the infection, leading to an epidemic. These factors may indeed have played a major role in the spread of the disease in the country, which was limited to Karachi till 2006. With recent natural disasters such as the earthquake in 2005 and flooding in 2010, 2011 and 2012, numbers of vector-borne diseases and outbreaks including dengue fever are on the rise in Pakistan. Therefore, it is a major concern for health sector workers and of utmost importance to have some understanding of the factors affecting disease outbreak for better risk assessment in the region. In the following report we review the climatic as well as host- and vector-associated factors involved in the outbreak of dengue epidemics in Pakistan and highlight high-risk zones in the country.


Assuntos
Dengue/epidemiologia , Surtos de Doenças , Mosquitos Vetores/crescimento & desenvolvimento , Humanos , Paquistão/epidemiologia , Estações do Ano , Temperatura
6.
Environ Geochem Health ; 37(3): 515-27, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25471479

RESUMO

Aims of this study were to provide firsthand data on the incidence of trace metals in human seminal plasma and find possible correlations between levels of toxic metals and semen quality of Pakistani population. Human semen samples were collected from male partners of couples undergoing infertility assessment at the National Institute of Health Islamabad (Pakistan). We investigated seventy-five seminal plasma samples, which were further categorized into three groups (normozoospermia, oligozoospermia and azoospermia) according to WHO guidelines. The concentration of 17 different toxic metals in human seminal plasma was determined simultaneously by using Inductively coupled plasma mass spectrometry (ICP-MS). Out of 17 trace metals, Cd and Ni showed significant difference (p < 0.05) among three monitored groups. Ni and Cd concentrations in the seminal plasma were negatively correlated with sperm concentration (r = -0.26, -0.29) and motility (r = -0.33, -0.37), respectively. This study suggested that exposure of Ni and Cd is mainly related with the consumption of contaminated dietary items, including ghee (cooking oil), flour and other agri-products. In some semen samples, the concentrations of Sn, V, Cu, Pb, Cr and Hg exhibited high levels suggesting a recent human exposure to surrounding sources. In Pakistani human semen samples, the levels of trace metals were lower and/or comparable to that found in populations of other countries. The results show the first evidence of the effect of toxic metals on semen quality and male infertility in Pakistan.


Assuntos
Infertilidade Masculina/epidemiologia , Metais Pesados/análise , Análise do Sêmen , Sêmen/química , Oligoelementos/análise , Cádmio/análise , Humanos , Masculino , Níquel/análise , Paquistão/epidemiologia
7.
Diagn Microbiol Infect Dis ; 109(4): 116346, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38759540

RESUMO

Rotaviruses belong to genotype VP4-P[8] are a significant cause of severe loose diarrhea in infants and young children. In the present study, we characterised the complete genome of three of the Pakistani P[8]b RVA strains by Illumina HiSeq sequencing technology to determine the complete genotype constellation providing insight into the evolutionary dynamics of their genes using maximum likelihood analysis. The maximum genomic sequences of our study strains were similar to more recent human Wa-Like G1P[8]a, G3P[8]a, G4P[6], G4P[8], G9P[4], G9P[8]a, G11P[25],G12P[8]a and G12P[6] strains circulating around the world. Therefore, strains PAK274, PAK439 and PAK624 carry natively distinctive VP4 gene with universally common human Wa-Like genetic backbone. Comparing our study P[8]b strains with vaccines strains RotarixTM and RotaTeqTM, multiple amino acid differences were examined between vaccine virus antigenic epitopes and Pakistani isolates. Over time, these differences may result in the selection for strains that will escape the vaccine-induced RVA-neutralizing-antibody effect.


Assuntos
Antígenos Virais , Proteínas do Capsídeo , Epitopos , Genoma Viral , Genótipo , Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Rotavirus/genética , Rotavirus/classificação , Rotavirus/imunologia , Rotavirus/isolamento & purificação , Humanos , Infecções por Rotavirus/virologia , Paquistão , Vacinas contra Rotavirus/imunologia , Epitopos/genética , Epitopos/imunologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Genoma Viral/genética , Antígenos Virais/genética , Antígenos Virais/imunologia , Lactente , Filogenia , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/genética , Pré-Escolar
8.
Sci Rep ; 14(1): 14569, 2024 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914650

RESUMO

Mastitis is considered one of the most widespread infectious disease of cattle and buffaloes, affecting dairy herds. The current study aimed to characterize the Staphylococcus aureus isolates recovered from subclinical mastitis animals in Pothohar region of the country. A total of 278 milk samples from 17 different dairy farms around two districts of the Pothohar region, Islamabad and Rawalpindi, were collected and screened for sub clinical mastitis using California Mastitis Test. Positive milk samples were processed for isolation of Staphylococcus aureus using mannitol salt agar. The recovered isolates were analyzed for their antimicrobial susceptibility and virulence genes using disc diffusion and PCR respectively. 62.2% samples were positive for subclinical mastitis and in total 70 Staphylococcus aureus isolates were recovered. 21% of these isolates were determined to be methicillin resistant, carrying the mecA gene. S. aureus isolates recovered during the study were resistant to all first line therapeutic antibiotics and in total 52% isolates were multidrug resistant. SCCmec typing revealed MRSA SCCmec types IV and V, indicating potential community-acquired MRSA (CA-MRSA) transmission. Virulence profiling revealed high prevalence of key genes associated with adhesion, toxin production, and immune evasion, such as hla, hlb, clfA, clfB and cap5. Furthermore, the Panton-Valentine leukocidin (PVL) toxin, that is often associated with recurrent skin and soft tissue infections, was present in 5.7% of isolates. In conclusion, the increased prevalence of MRSA in bovine mastitis is highlighted by this study, which also reveals a variety of virulence factors in S. aureus and emphasizes the significance of appropriate antibiotic therapy in combating this economically burdensome disease.


Assuntos
Antibacterianos , Mastite Bovina , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Bovinos , Mastite Bovina/microbiologia , Feminino , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/veterinária , Paquistão , Virulência/genética , Antibacterianos/farmacologia , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fatores de Virulência/genética , Testes de Sensibilidade Microbiana , Leite/microbiologia , Proteínas de Bactérias/genética
9.
J Infect Public Health ; 16(2): 266-271, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36621204

RESUMO

BACKGROUND: Neonatal sepsis has high incidence with significant mortality and morbidity rates in Pakistan. We investigated common etiological patterns of neonatal sepsis at a tertiary care setup. METHODS: 90 pus and blood, gram negative and gram positive bacterial isolates were analyzed for virulence and antibiotic resistance gene profiling using PCR and disc diffusion methods. RESULTS: Staphylococcus aureus showed strong association with neonatal sepsis (43 %) followed by Citrobacter freundii (21 %), Pseudomonas aeruginosa (13 %), Escherichia coli (15 %) and Salmonella enterica (8 %). Molecular typing of E. coli isolates depicted high prevalence of the virulent F and B2 phylogroups, with 4 hypervirulent phylogroup G isolates. 76.9 % S. aureus isolates showed presence of Luk-PV, encoding for Panton-valentine leucocidin (PVL) toxin with majority also carrying MecA gene and classified as methicillin resistant S. aureus (MRSA). ecpA, papC, fimH and traT virulence genes were detected in E. coli and Salmonella isolates. 47 % Citrobacter freundii isolates carried the shiga like toxin SltII B. Antimicrobial resistance profiling depicted common resistance to cephalosporins, beta lactams and fluoroquinolones. CONCLUSION: Presence of PVL carrying MRSA and multidrug resistant gram negative bacteria, all isolated from late onset sepsis neonates indicate a predominant nosocomial transmission pattern which may complicate management of the disease in NICU setups.


Assuntos
Infecção Hospitalar , Staphylococcus aureus Resistente à Meticilina , Sepse Neonatal , Infecções Estafilocócicas , Humanos , Recém-Nascido , Antibacterianos/farmacologia , Infecção Hospitalar/epidemiologia , Escherichia coli , Exotoxinas/genética , Leucocidinas/genética , Testes de Sensibilidade Microbiana , Paquistão/epidemiologia , Prevalência , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Centros de Atenção Terciária , Resistência a Múltiplos Medicamentos
10.
ACS Omega ; 8(29): 25808-25816, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37521645

RESUMO

Tamoxifen is the drug of choice as hormonal therapy for hormone receptor-positive breast cancers and can reduce the risk of breast cancer recurrence. However, oral tamoxifen has a low bioavailability due to liver and intestinal metabolic passes. To overcome this problem and utilize the potential of this drug to its maximum, inorganic nanoparticle carriers have been exploited and tested to increase its bioavailability. Biocompatibility and unique magnetic properties make iron oxide nanoparticles an excellent choice as a drug delivery system. In this study, we developed and tested a "green synthesis" approach to synthesize iron nanoparticles from green tea extract and coated them with agar for longer stability (AG-INPs). Later, these hybrid nanoparticles were conjugated with tamoxifen (TMX). By using this approach, we synthesized stable agar-coated tamoxifen-conjugated iron nanoparticles (TMX-AG-INPs) and characterized them with Fourier-transform infrared (FTIR) spectroscopy. The average particle size of AG-INPs was 26.8 nm, while the average particle size of tamoxifen-loaded iron nanoparticles, TMX-AG-INPs, was 32.1 nm, as measured by transmission and scanning electron microscopy. The entrapment efficiency of TMX-AG-INPs obtained by the drug release profile was 88%, with a drug loading capacity of 43.5%. TMX-AG-INPs were significantly (p < 0.001) efficient in killing breast cancer cells when tested in vitro on the established breast cancer cell line MCF-7 by cell viability assay, indicating their potential to control cell proliferation.

11.
Sci Rep ; 13(1): 10043, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340022

RESUMO

Avian pathogenic E. coli (APEC) is associated with local and systemic infections in poultry, ducks, turkeys, and many other avian species, leading to heavy economical losses. These APEC strains are presumed to possess zoonotic potential due to common virulence markers that can cause urinary tract infections in humans. The prophylactic use of antibiotics in the poultry sector has led to the rapid emergence of Multiple Drug Resistant (MDR) APEC strains that act as reservoirs and put human populations at risk. This calls for consideration of alternative strategies to decrease the bacterial load. Here, we report isolation, preliminary characterization, and genome analysis of two novel lytic phage species (Escherichia phage SKA49 and Escherichia phage SKA64) against MDR strain of APEC, QZJM25. Both phages were able to keep QZJM25 growth significantly less than the untreated bacterial control for approximately 18 h. The host range was tested against Escherichia coli strains of poultry and human UTI infections. SKA49 had a broader host range in contrast to SKA64. Both phages were stable at 37 °C only. Their genome analysis indicated their safety as no recombination, integration and host virulence genes were identified. Both these phages can be good candidates for control of APEC strains based on their lysis potential.


Assuntos
Bacteriófagos , Infecções por Escherichia coli , Doenças das Aves Domésticas , Animais , Humanos , Escherichia coli/genética , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/microbiologia , Bacteriófagos/genética , Aves/microbiologia , Aves Domésticas , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/microbiologia , Galinhas
12.
Sci Rep ; 12(1): 4161, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264739

RESUMO

Worldwide, breast cancer has an eminent morbidity and mortality rate, as it is a neoplastic disease among females. The query of the prospective danger of bovine leukemia virus (BLV) to humans is an old but exceedingly topical focus of scientific debate. The objective of the current study was to determine the possible relationship between BLV and breast cancer. A total of 2710 formalin-fixed paraffin-embedded (FFPE) breast cancer samples were selected regardless of the age, ethnicity, or municipality origin of the subjects. The presence of BLV in human breast cancer was determined through nested PCR by amplifying tax and gag genes followed by partial sequencing. Homology was confirmed by using the online BLAST Tool. BLV genes were found to be positive in 26.8% (728/2710) of the samples from breast cancer patients and 10% (10/80) of the samples without cancer (negative control). The results indicated a correlation between the presence of the BLV gene and breast cancer (odds ratio = 0.3889; confidence interval = 1,18; p = 0.0029). The current findings suggest a possible link between BLV and human breast carcinoma. Therefore, screening cattle herds and milk products is suggested to reduce the viral transmission risk to humans.


Assuntos
Neoplasias da Mama , Vírus da Leucemia Bovina , Animais , Neoplasias da Mama/patologia , Bovinos , DNA Viral/genética , Feminino , Humanos , Vírus da Leucemia Bovina/genética , Masculino , Reação em Cadeia da Polimerase , Estudos Prospectivos
13.
Viruses ; 14(8)2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35893699

RESUMO

Foot and mouth disease (FMD) causes severe economic losses to the livestock industry of endemic countries, including Pakistan. Pakistan is part of the endemic pool 3 for foot and mouth disease viruses (FMDV), characterized by co-circulating O, A, and Asia 1 serotypes, as designated by the world reference laboratory for FMD (WRL-FMD). FMDV serotype A lineage ASIA/Iran-05 is widespread in buffalos and cattle populations and was first reported in Pakistan in 2006. This lineage has a high turnover, with as many as 10 sub-lineages reported from Pakistan over the years. In this study, we reconstructed the evolutionary, demographic, and spatial history of serotype A and one of its sub-lineages, A/ASIA/Iran-05/SIS-13, prevalent in Pakistan. We sequenced nearly complete genomes of three isolates belonging to sub-lineage A/ASIA/Iran-05/SIS-13. We estimated recombination patterns and natural selection acting on the serotype A genomes. Source and transmission routes in Pakistan were inferred, and the clustering pattern of isolates of the SIS-13 sub-lineage were mapped on a tree. We hereby report nearly complete genome sequences of isolates belonging to sub-lineage A/ASIA/Iran-05/SIS-13, along with purported recombinant genomes, and highlight that complete coding sequences can better elucidate the endemic history and evolutionary pressures acting on long-term co-circulating FMDV strains.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Animais , Bovinos , Febre Aftosa/epidemiologia , Irã (Geográfico) , Paquistão/epidemiologia , Filogenia , Sorogrupo
14.
Viruses ; 14(2)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35215834

RESUMO

Salmonella Typhimurium, a foodborne pathogen, is a major concern for food safety. Its MDR serovars of animal origin pose a serious threat to the human population. Phage therapy can be an alternative for the treatment of such MDR Salmonella serovars. In this study, we report on detailed genome analyses of a novel Salmonella phage (Salmonella-Phage-SSBI34) and evaluate its therapeutic potential. The phage was evaluated for latent time, burst size, host range, and bacterial growth reduction in liquid cultures. The phage stability was examined at various pH levels and temperatures. The genome analysis (141.095 Kb) indicated that its nucleotide sequence is novel, as it exhibited only 1-7% DNA coverage. The phage genome features 44% GC content, and 234 putative open reading frames were predicted. The genome was predicted to encode for 28 structural proteins and 40 enzymes related to nucleotide metabolism, DNA modification, and protein synthesis. Further, the genome features 11 tRNA genes for 10 different amino acids, indicating alternate codon usage, and hosts a unique hydrolase for bacterial lysis. This study provides new insights into the subfamily Vequintavirinae, of which SSBI34 may represent a new genus.


Assuntos
Myoviridae/genética , Fagos de Salmonella/genética , Salmonella typhimurium/virologia , Animais , Bacteriólise , Agentes de Controle Biológico , Genoma Viral , Especificidade de Hospedeiro , Myoviridae/classificação , Myoviridae/isolamento & purificação , Myoviridae/fisiologia , Fases de Leitura Aberta , Terapia por Fagos , Filogenia , Aves Domésticas/microbiologia , Infecções por Salmonella/terapia , Fagos de Salmonella/classificação , Fagos de Salmonella/isolamento & purificação , Fagos de Salmonella/fisiologia , Salmonella typhimurium/isolamento & purificação
15.
Sci Rep ; 12(1): 2790, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35181674

RESUMO

Lower respiratory illness is one of the leading causes of death among children in low- and high-income countries. Human metapneumovirus (hMPV) is a key contributor to respiratory illnesses commonly reported among children and causes serious clinical complications ranging from mild respiratory infections to severe lower respiratory tract anomalies mainly in the form of bronchiolitis and pneumonia. However, due to the lack of a national surveillance system, the clinical significance of hMPV remains obscure in the Pakistani population. This study was conducted to screen throat swabs samples collected from 127 children reported with respiratory symptoms at a tertiary care hospital in Islamabad. Out of 127, 21 (16.5%) samples were positive for hMPV with its genotype distribution as A2a (10%), A2b (20%), B1 (10%), and B2 (60%). Phylogenetic analysis showed that the hMPV viruses were closely related to those reported from neighboring countries including India and China. This work will contribute to a better understanding of this virus, its diagnosis, and the handling of patients in clinical setups. Further studies at a large-scale are warranted for a better understanding of the disease burden and epidemiology of hMPV in Pakistan.


Assuntos
Metapneumovirus/isolamento & purificação , Infecções por Paramyxoviridae/diagnóstico , Infecções Respiratórias/diagnóstico , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Masculino , Metapneumovirus/genética , Metapneumovirus/patogenicidade , Epidemiologia Molecular , Paquistão/epidemiologia , Infecções por Paramyxoviridae/epidemiologia , Infecções por Paramyxoviridae/genética , Infecções por Paramyxoviridae/virologia , Filogenia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/genética , Infecções Respiratórias/virologia
16.
Sci Rep ; 12(1): 5732, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35388062

RESUMO

Salmonella enterica serovar Typhimurium is a foodborne pathogen causing occasional outbreaks of enteric infections in humans. Salmonella has one of the largest pools of temperate phages in its genome that possess evolutionary significance for pathogen. In this study, we characterized a novel temperate phage Salmonella phage BIS20 (BIS20) with unique tail fiber genes. It belongs to the subfamily Peduovirinae genus Eganvirus and infects Salmonella Typhimurium strain (SE-BS17; Acc. NO MZ503545) of poultry origin. Phage BIS20 was viable only at biological pH and temperature ranges (pH7 and 37 °C). Despite being temperate BIS20 significantly slowed down the growth of host strain for 24 h as compared to control (P < 0.009). Phage BIS20 features 29,477-base pair (bp) linear DNA genome with 53% GC content and encodes for 37 putative ORFs. These ORFs have mosaic arrangement as indicated by its ORF similarity to various phages and prophages in NCBI. Genome analysis indicates its similarity to Salmonella enterica serovar Senftenberg prophage (SEStP) sequence (Nucleotide similarity 87.7%) and Escherichia virus 186 (~ 82.4% nucleotide similarity). Capsid genes were conserved however those associated with tail fiber formation and assembly were unique to all members of genus Eganvirus. We found strong evidence of recombination hotspot in tail fiber gene. Our study identifies BIS20 as a new species of genus Eganvirus temperate phages as its maximum nucleotide similarity is 82.4% with any phage in NCBI. Our findings may contribute to understanding of origin of new temperate phages.


Assuntos
Bacteriófagos , Fagos de Salmonella , Bacteriófagos/genética , Genoma Viral , Humanos , Myoviridae/genética , Nucleotídeos , Prófagos/genética , Salmonella , Fagos de Salmonella/genética , Salmonella typhimurium/genética
17.
Virus Res ; 299: 198437, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-33901591

RESUMO

Viruses are the primary cause of acute gastroenteritis in children all over the world. Understanding the emergence and genetic variation of these viruses may help to prevent infections. Aichivirus (AiV) is a member of the Kobuvirus genus, which currently contains six officially recognized species: Aichivirus A-F. The species AiV A contains six types including Aichivirus 1 (AiV 1) and eventually, three genotypes have been identified in the human AiV 1 (named A to C). The present study describes the identification and sequencing of the polyprotein gene of a human AiV 1 strain PAK419 via NGS in Pakistani children with acute gastroenteritis. Our study strain PAK419 was classified as AiV 1 genotype A, most commonly found in Japan and Europe, and closely related to non-Japanese and European strains on the phylogenetic tree. PAK419 showed 95-98 % nucleotide sequence identity with strains isolated from Ethiopia (ETH/2016/P4), Australia (FSS693) and China (Chshc7). On phylogenetic observation PAK419 formed a distinct cluster in the AiV 1 genotype A with the above mentioned and other human AiV strains detected around the world (Germany, Brazil, Japan, Thailand, Korea and Vietnam). The data clearly showed that Pakistani AiV strains and human strains identified from all over the world are distinct from Aichivirus strains found in bovine, swine, canine, feline, caprine, ferret, bat, and environmental samples. The distinguishing characteristics of the AiV genome showed a lower probability of inter-genotypic recombination events, which may support the lack of AiV serotypes. PAK419 also had a high content of C nucleotide (37.4 %), as found in previous studies, which could also restrict the possible genetic variation of AiV. This study demonstrate the power of NGS in uncovering unknown gastroenteric etiological agents circulating in the population.


Assuntos
Gastroenterite , Kobuvirus , Infecções por Picornaviridae , Animais , Gatos , Bovinos , Cães , Fezes , Furões , Gastroenterite/epidemiologia , Genótipo , Cabras , Humanos , Kobuvirus/genética , Paquistão/epidemiologia , Filogenia , Infecções por Picornaviridae/veterinária , Suínos
18.
Crit Rev Microbiol ; 36(2): 91-133, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20345213

RESUMO

Hepatitis C (HCV) is the disease that has affected around 200 million people globally. HCV is a life threatening human pathogen, not only because of its high prevalence and worldwide burden but also because of the potentially serious complications of persistent HCV infection. Chronicity of the disease leads to cirrhosis, hepatocellular carcinoma and end-stage liver disease. HCV positive hepatocytes vary between less than 5% and up to 100%, indicating the high rate of replication of viral RNA. HCV has a very high mutational rate that enables it to escape the immune system. Viral diversity has two levels; the genotypes and Quasiaspecies. Major HCV genotypes constitute genotype 1, 2, 3, 4, 5 and 6 while more than 50 subtypes are known. All HCV genotypes have their particular patterns of geographical distribution and a slight drift in viral population has been observed in some parts of the globe.


Assuntos
Hepacivirus/patogenicidade , Hepatite C/epidemiologia , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/virologia , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/complicações , Humanos , Evasão da Resposta Imune , Cirrose Hepática/epidemiologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/virologia , Mutação , Polimorfismo Genético , RNA Viral/genética
19.
Virus Res ; 290: 198178, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33010373

RESUMO

Human parechoviruses (HPeVs) are highly common pathogens in children under 2 years of age. Of the 19 distinct HPeV genotypes identified worldwide, HPeV1 is still the most prevalent type associated with respiratory and gastrointestinal symptoms in infants and young children. Pakistan's previous studies have focused only on the detection and partial sequencing of HPeV genotypes. In the present study, we have obtained the complete genomes of 2 HPeV1 strains (PAK419 and PAK663) from children using NGS method on Illumina Hiseq Platform. These samples were collected from children suffering from acute gastroenteritis in Rawalpindi, Pakistan during 2016. The near complete genome sequences obtained for two HPeV1 strains (PAK419 and PAK663) consist of total 6877 nucleotides with a single, large open reading frame (ORF) encoding a polyprotein gene. Phylogenetic analysis showed that both HPeV1 strains exhibited maximum amino acid similarity (97 %) to HPeV1 strains from The Nederlands (2007-863, GQ183034) and clustered closely with this and with other HPeV1 strains isolated from other countries in the world (Ethiopia, Taiwan, Russia and Brazil). A motif of arginine-glycine-aspartic acid (RGD) in the VP1 (Outer capsid protein) C-terminus region that is suggested to help virus entry into the host cell also identified in PAK419 and PAK663. SimPlot analysis revealed that intergenotypic recombination events may have take place in the non-structural region between both HPeV1 strains (PAK419, PAK663), two major strains of HPeV1 (GQ183034 and MG873157) and four minor strains of HPeV4 (AM235750), HPeV7 (EU556224), HPeV15 (MN265386) and HPeV18 (KT879915). The full genome of HPeV1 strains characterized in the current study will provide complete information on these newly isolated strains for further preventive or treatment measures.


Assuntos
Genoma Viral , Genótipo , Parechovirus/genética , Sequenciamento Completo do Genoma , Fezes/virologia , Humanos , Metagenômica , Fases de Leitura Aberta , Paquistão/epidemiologia , Parechovirus/classificação , Filogenia , Infecções por Picornaviridae/epidemiologia , Infecções por Picornaviridae/virologia , RNA Viral/genética , Análise de Sequência de DNA
20.
Front Immunol ; 11: 625157, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33391290

RESUMO

[This corrects the article DOI: 10.3389/fimmu.2020.562282.].

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