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2.
J Med Virol ; 87(4): 656-63, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25611467

RESUMO

Human Bocaviruses (HBoV) have been detected in human respiratory and gastrointestinal infections worldwide. Four genotypes of HBoV (HBoV1-4) have been described; HBoV-1 is associated with respiratory tract infections while HBoV-2, -3, and -4 genotypes are considered as entero-pathogenic although the exact role largely remains unclear. The global prevalence of HBoV has been reported, but the epidemiological data from Pakistan is largely unavailable to date. This study was conducted to understand the genetic diversity and disease prevalence of HBoV in hospitalized Pakistani children with acute diarrhea. During 2009, a total of 365 stool samples were collected from children hospitalized with gastrointestinal symptoms (as per WHO case definitions) at Rawalpindi General Hospital, Pakistan. Demographic and clinical data were recorded using a standardized questionnaire. The samples were tested for HBoV and rotavirus using real-time RT-PCR and ELISA, respectively. There were 47 (13%) samples positive for HBoV with 98% (n = 46) showing co-infection with rotavirus. HBoV-1 was the most frequently detected and was found in 94% samples followed by HBoV-2 and HBoV-3 genotypes. The mean age of infected children was 7.57 ± 5.4 months while detection was more frequent in males (n = 32, 68%). All cases recovered after 2.43 ± 1.0 mean days of treatment. On phylogenetic analysis, HBoV strains from Pakistan clustered closely with viruses from neighboring Bangladesh and China. These findings represent the first known epidemiological study in Pakistan to investigate the role of HBoV in acute gastroenteritis. The clinical data demonstrates that HBoV is not significantly associated with gastroenteritis alone and predominantly co-infections with rotavirus are found.


Assuntos
Diarreia/epidemiologia , Diarreia/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Bocavirus Humano/isolamento & purificação , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Distribuição por Idade , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , Ensaio de Imunoadsorção Enzimática , Fezes/virologia , Feminino , Variação Genética , Genótipo , Bocavirus Humano/classificação , Bocavirus Humano/genética , Humanos , Lactente , Masculino , Epidemiologia Molecular , Filogenia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/genética , Rotavirus/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência , Distribuição por Sexo
3.
J Infect Dev Ctries ; 15(3): 366-369, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33839711

RESUMO

Pandemic of novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infections in China is now become global public health crisis. At present 87.64% of the world is infected by this deadly illness. The risk from this epidemic depends on the nature of the virus, including how well it transmits from person to person, and the complications resulting from this current illness. The novel coronavirus has killed thousands of people in China and other countries as well; its rate of mortality is increasing day by day. There is an urgent need to control the virus by developing vaccine or any other antiviral drugs to save the world from this deadly viral infection.


Assuntos
COVID-19/epidemiologia , COVID-19/transmissão , Saúde Global/estatística & dados numéricos , Saúde Pública , SARS-CoV-2/patogenicidade , Antivirais/uso terapêutico , COVID-19/mortalidade , China/epidemiologia , Países em Desenvolvimento , Humanos
4.
PLoS One ; 16(3): e0248371, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33755704

RESUMO

Since its emergence in China, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide including Pakistan. During the pandemic, whole genome sequencing has played an important role in understanding the evolution and genomic diversity of SARS-CoV-2. Although an unprecedented number of SARS-CoV-2 full genomes have been submitted in GISAID and NCBI, data from Pakistan is scarce. We report the sequencing, genomic characterization, and phylogenetic analysis of five SARS-CoV-2 strains isolated from patients in Pakistan. The oropharyngeal swabs of patients that were confirmed positive for SARS-CoV-2 through real-time RT-PCR at National Institute of Health, Pakistan, were selected for whole-genome sequencing. Sequencing was performed using NEBNext Ultra II Directional RNA Library Prep kit for Illumina (NEW ENGLAND BioLabs Inc., MA, US) and Illumina iSeq 100 instrument (Illumina, San Diego, US). Based on whole-genome analysis, three Pakistani SARS-CoV-2 strains clustered into the 20A (GH) clade along with the strains from Oman, Slovakia, United States, and Pakistani strain EPI_ISL_513925. The two 19B (S)-clade strains were closely related to viruses from India and Oman. Overall, twenty-nine amino acid mutations were detected in the current study genome sequences, including fifteen missense and four novel mutations. Notably, we have found a D614G (aspartic acid to glycine) mutation in spike protein of the sequences from the GH clade. The G614 variant carrying the characteristic D614G mutation has been shown to be more infectious that lead to its rapid spread worldwide. This report highlights the detection of GH and S clade strains and G614 variant from Pakistan warranting large-scale whole-genome sequencing of strains prevalent in different regions to understand virus evolution and to explore their genetic diversity.


Assuntos
Variação Genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Idoso de 80 Anos ou mais , COVID-19/patologia , COVID-19/virologia , Feminino , Deleção de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Orofaringe/virologia , Paquistão , Filogenia , RNA Viral/química , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2/classificação , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/metabolismo , Sequenciamento Completo do Genoma , Adulto Jovem
5.
Saudi J Biol Sci ; 28(2): 1226-1232, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33613051

RESUMO

Some nanoscale morphologies of titanium oxide nanostructures blend with gold nanoparticles and act as satellites and targeted weapon methodologies in biomedical applications. Simultaneously, titanium oxide can play an important role when combined with gold after blending with polyethylene glycol (PEG). Our experimental approach is novel with respect to the plasmonic role of metal nanoparticles as an efficient PDT drug. The current experimental strategy floats the comprehensive and facile way of experimental strategy on the critical influence that titanium with gold nanoparticles used as novel photosensitizing agents after significant biodistribution of proposed nanostructures toward targeted site. In addition, different morphologies of PEG-coated Au-doped titanium nanostructures were shown to provide various therapeutic effects due to a wide range of electromagnetic field development. This confirms a significantly amplified population of hot electron generation adjacent to the interface between Au and TiO2 nanostructures, leading to maximum cancerous cell injury in the MCF-7 cell line. The experimental results were confirmed by applying a least squares fit math model which verified our results with 99% goodness of fit. These results can pave the way for comprehensive rational designs for satisfactory response of performance phototherapeutic model mechanisms along with new horizons of photothermal therapy (HET) and photodynamic therapy (HET) operating under visible and near-infrared (NIR) light.

6.
Saudi J Biol Sci ; 28(1): 942-947, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33424386

RESUMO

The sudden outbreak of the novel Coronavirus infectious disease (COVID-19) resulted in significant challenges to global health systems. One of the primary challenges is rapid, reliable, and accurate detection of the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) virus among the suspected COVID-19-infected individuals. At present, quantitative real-time PCR (qRT-PCR) is a widely used diagnostic method. However, it requires expensive instruments and expertise in the interpretation of results. These constraints reflect the significant need for the development of alternative diagnostic options. This study will validate the use and efficiency of the reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay as a potential alternative for the detection of COVID-19. For this purpose, a cohort of 297 suspected COVID-19 patients was tested using both the RT-LAMP assay and the conventional RT-PCR method. For the RT-LAMP assay, three genes (orf-1ab, N, and S) were identified as the target sites for the detection of COVID-19. Based on a comparative assessment, 117 out of 124 positive COVID-19 cases were observed using the RT-LAMP technique with an overall 91.45% sensitivity. Interestingly, where a consensus on 163 individuals free of SARS-Cov-2 was observed, RT-LAMP specificity was 90%. Based on these findings, the robustness of the technique, and the reduced dependency on expensive instrumentation, RT-LAMP-based COVID-19 detection is strongly recommended as a potential alternative assay.

7.
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
8.
Saudi J Biol Sci ; 27(12): 3199-3207, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33304125

RESUMO

This study focuses on the synthesis, characterization, and assessment of the synergistic effect of 2,2,6,6, tetramethylpiperidine-N-oxyl (TEMPO)-coated titanium dioxide nanorods (TiO2 NRs) for photodynamic therapy (PDT). Firstly, TiO2 NRs were synthesized by the sol-gel technique. Then, TEMPO was grafted on TiO2 NRs with the aid of oxoammonium salts. Next, the final product was characterized by applying manifold characterization techniques. X-ray diffraction was used to perform crystallographic analysis; transmission electron microscopy (TEM) was used to conduct morphological analysis; Fourier transform infrared (FTIR) and Raman spectra were recorded to perform molecular fingerprint analysis. Furthermore, experimental and empirical modeling was performed to confirm the suitability of as-prepared samples for PDT applications using (MCF-7 cell line) Human Breast Cancer cell line. Our results revealed that bare TiO2 NRs did not exhibit a significant response for therapeutic applications compared to TEMPO-conjugated TiO2 NRs in the dark; however, they exhibited a prominent response for the PDT application under UV-A light. Therefore, it is concluded that TEMPO-coated TiO2 NRs shows the synergistic response for therapeutic approach under UV-A light irradiation. In addition, TEMPO capped TiO2 nanorods not only overcome the multidrug resistance (MDR) hindrance but also exhibit excellent response for cancer cell (MCF-7 cells) treatment only under UV light irradiation via PDT. It is expected that the proposed TiO2 NRs + TEMPO nanocomposite, which is suitable for PDT treatment, may be essential for photodynamic therapy.

10.
J Infect Public Health ; 11(4): 540-545, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29129527

RESUMO

BACKGROUND: Measles virus infection remains a significant cause of childhood mortality and morbidity despite continued global efforts and the availability of a safe and effective vaccine. Molecular analysis of indigenous measles viruses could provide critical information on outbreak linkages and transmission pathways that can aid the implementation of appropriate control programs in Pakistan. METHODS: Blood samples and throat swabs were collected from subjects suspected with measles in Islamabad, Pakistan from 2013 to 2015. Serum samples were tested for the presence of measles immunoglobulin M (IgM) antibodies using enzyme-linked immunosorbent assay (ELISA) while throat swabs were used for the isolation (Vero/SLAM cell line) and subsequent characterization and phylogenetic analysis of measles strains. RESULTS: Of 373 blood samples, 66% tested positive for measles IgM. Male subjects were more often infected (58%) than female (42%) with the highest frequency of positive cases (63%) in the 0-5-years age group. Among the positive cases, only 13% had received one or two doses of the measles vaccine, while 87% were unvaccinated. Of 80 throat swabs, 29 (36%) showed a measles virus-specific cytopathic effect (CPE) and were characterized as genotype B3 through partial sequencing of the nucleoprotein (N) gene. Phylogenetic analysis revealed the Pakistani B3 strains to be closely related to strains from neighboring countries (Iran and Afghanistan) as well as with B3 viruses from the USA, Germany, and the UK. CONCLUSIONS: The study results showed that despite the availability of an effective vaccine, the burden of measles infections is very high in Pakistan due to poor routine immunization coverage even in major cities, including the capital city of Islamabad. It is imperative that national health authorities take urgent strategic steps to improve routine immunization and implement adequate molecular identification methods to tackle future measles outbreaks.


Assuntos
Genótipo , Vírus do Sarampo/genética , Sarampo/epidemiologia , Sarampo/virologia , Afeganistão/epidemiologia , Anticorpos Antivirais/sangue , Pré-Escolar , Surtos de Doenças , Ensaio de Imunoadsorção Enzimática , Europa (Continente)/epidemiologia , Feminino , Humanos , Imunoglobulina M/sangue , Lactente , Recém-Nascido , Irã (Geográfico)/epidemiologia , Masculino , Sarampo/sangue , Sarampo/prevenção & controle , Vacina contra Sarampo/administração & dosagem , Vírus do Sarampo/isolamento & purificação , Proteínas do Nucleocapsídeo , Nucleoproteínas/genética , Paquistão/epidemiologia , Faringe/virologia , Filogenia , RNA Viral/genética , Estados Unidos/epidemiologia , Vacinação/estatística & dados numéricos , Proteínas Virais/genética
11.
PLoS One ; 8(6): e67998, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23825693

RESUMO

Pakistan harbors high disease burden of gastro-enteric infections with majority of these caused by rotavirus. Unfortunately, lack of proper surveillance programs and laboratory facilities have resulted in scarcity of available data on rotavirus associated disease burden and epidemiological information in the country. We investigated 1306 stool samples collected over two years (2008-2009) from hospitalized children under 5 years of age for the presence of rotavirus strains and its genotypic diversity in Lahore. The prevalence rate during 2008 and 2009 was found to be 34% (n = 447 out of 1306). No significant difference was found between different age groups positive for rotavirus (p>0.05). A subset of EIA positive samples was further screened for rotavirus RNA through RT-PCR and 44 (49.43%) samples, out of total 89 EIA positive samples, were found positive. G and P type prevalence was found as follows: G1P [4] = 3(6.81%); G1P [6] = 9(20.45%); G1P [8] = 1(2.27%); G2P [4] = 21(47.72%); G2P [8] = 1(2.27%); G9P [4] = 1(2.27%); G9P [6] = 1(2.27%) and G9P [8] = 7(15.90%). Phylogenetic analysis revealed that the VP7 and VP4 sequences clustered closely with the previously detected strains in the country as well as Belgian rotaviruses. Antigenic characterization was performed by analyzing major epitopes in the immunodominant VP7 and VP4 gene segments. Although the neutralization conferring motifs were found variable between the Pakistani strains and the two recommended vaccines strains (Rotarix™ and RotaTeq™), we validate the use of rotavirus vaccine in Pakistan based on the proven and recognized vaccine efficacy across the globe. Our findings constitute the first report on rotavirus' genotype diversity, their phylogenetic relatedness and epidemiology during the pre-vaccination era in Lahore, Pakistan and support the immediate introduction of rotavirus vaccine in the routine immunization program of the country.


Assuntos
Gastroenterite/epidemiologia , Gastroenterite/virologia , Variação Genética , Rotavirus/genética , Rotavirus/fisiologia , Doença Aguda/epidemiologia , Doença Aguda/terapia , Sequência de Aminoácidos , Antígenos Virais/química , Antígenos Virais/genética , Antígenos Virais/imunologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Pré-Escolar , Desidratação/complicações , Diarreia/complicações , Diarreia/epidemiologia , Diarreia/terapia , Diarreia/virologia , Epitopos/química , Epitopos/imunologia , Gastroenterite/terapia , Genótipo , Hospitalização , Humanos , Dados de Sequência Molecular , Paquistão/epidemiologia , Filogenia , Prevalência , Rotavirus/imunologia , Vacinas Virais/imunologia
12.
Infect Genet Evol ; 14: 161-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23187023

RESUMO

Human group A rotaviruses (RVAs) possess a large genetic diversity and new RVA strains and G/P genotype combinations are been identified frequently. Only a few studies reporting the distribution and co-circulation of RVA G and P genotypes are available for Pakistan. This hospital based study showed a RVA prevalence rate of 23.8%, which is similar to RVA detection rates estimated in other Eastern Mediterranean countries. During 2010, the following RVA strains were found to co-circulate: G1P[8] and G2P[4] (both 24.3%), G1P[6] (12.1%), G9P[8] (10.8%), G9P[6] (5.4%), G12P[6] (6.7%), G6P[1] (2.7%) and mixed infections (6.7%). Sequence analyses of selected G1, G2, G9 and G12 RVA strains revealed a close evolutionary relationship with typical human RVA strains. Sequence identities among the Pakistani VP7 RVA genes encoding G1, G2, G9 and G12 ranged between 91.5-98.7%, 99.6-98.9%, 97.7-99.5% and 99.2-99.9%, respectively. Analysis of the VP4 genes revealed co-prevalence of distinct lineages of the P[8] genotype. P[6] and P[4] showed a close relationship with typical human RVA strains detected in several Asian countries. The two G6P[1] RVA strains were closely related to typical bovine RVA strains, suggesting one or multiple interspecies transmission events. Our data provide important baseline data on the burden of RVA disease and genotype distribution in Rawalpindi, Pakistan, which is important with respect to vaccine introduction in national immunization programs.


Assuntos
Antígenos Virais/genética , Proteínas do Capsídeo/genética , Filogenia , Infecções por Rotavirus/epidemiologia , Rotavirus/classificação , Rotavirus/genética , Pré-Escolar , Genótipo , Humanos , Lactente , Recém-Nascido , Dados de Sequência Molecular , Paquistão/epidemiologia , Prevalência
13.
PLoS One ; 7(8): e41866, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22916112

RESUMO

BACKGROUND: In early 2009, a novel influenza A(H1N1) virus that emerged in Mexico and United States rapidly disseminated worldwide. The spread of this virus caused considerable morbidity with over 18000 recorded deaths. The new virus was found to be a reassortant containing gene segments from human, avian and swine influenza viruses. METHODS/RESULTS: The first case of human infection with A(H1N1)pdm09 in Pakistan was detected on 18(th) June 2009. Since then, 262 laboratory-confirmed cases have been detected during various outbreaks with 29 deaths (as of 31(st) August 2010). The peak of the epidemic was observed in December with over 51% of total respiratory cases positive for influenza. Representative isolates from Pakistan viruses were sequenced and analyzed antigenically. Sequence analysis of genes coding for surface glycoproteins HA and NA showed high degree of high levels of sequence identity with corresponding genes of regional viruses circulating South East Asia. All tested viruses were sensitive to Oseltamivir in the Neuraminidase Inhibition assays. CONCLUSIONS: Influenza A(H1N1)pdm09 viruses from Pakistan form a homogenous group of viruses. Their HA genes belong to clade 7 and show antigenic profile similar to the vaccine strain A/California/07/2009. These isolates do not show any amino acid changes indicative of high pathogenicity and virulence. It is imperative to continue monitoring of these viruses for identification of potential variants of high virulence or drug resistance.


Assuntos
Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/epidemiologia , Epidemiologia Molecular , Glicosilação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Vírus da Influenza A Subtipo H1N1/enzimologia , Vírus da Influenza A Subtipo H1N1/metabolismo , Influenza Humana/virologia , Neuraminidase/metabolismo , Paquistão/epidemiologia , Filogenia
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