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1.
Virusdisease ; 32(1): 137-139, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33969157

RESUMO

Epstein-Barr Virus (EBV) is associated with the Hodgkin's and Non-Hodgkin's lymphoma (HL and NHL respectively). HIV is a risk factor for EBV infections and previously published data indicate that HIV infected individuals have higher chances of getting EBV infections compared to HIV uninfected individuals. Very limited information is available from India about the the prevalence of EBV in HIV positivity, with or without malignancy. In a recent study (Sinha et al. Current HIV Res 16:1-6, 2018) from All India Institute of Medical Sciences (AIIMS), New Delhi, we have shown that 2% among the HIV-1 infected individuals have malignancies including HL and NHL. To determine the prevalence of EBV among these individuals, clinical specimen obtained from ART clinic of AIIMS were tested for the presence of EBV DNA in plasma samples by quantitative real-time PCR. We have observed high prevalence of EBV (30%) among the 92 specimen tested. Prevalence is higher in patients with malignancy (37%) compared to those without maliganancy (27%). No correlation was observed with the CD4 counts or HIV viral load with EBV positivity.

2.
Virusdisease ; 31(2): 71-74, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32313825

RESUMO

Recent novel coronavirus outbreak in Wuhan City of Hubei province in China infected nearly 70,000 individuals and killed more than 1700 people within a short span of time leading to global pandemic. The disease is now spread to 26 countries in Asia, North America, Europe and Australasia. The virus is spreading rapidly to Asia-pacific and Southeast Asian countries. The disease is posing a serious threat to human population and has devastating impact on public health and economy. So far 3 Indians are infected and India is at risk of rapid spread of the disease because of its geographical location and other favorable conditions. With a poorer global health security index compared to China (India-57 and China-51), any such situation will have worse outcome. In near future there are also possibilities of similar kind of disease outbreak caused by new strains of coronaviruses due to factors like species jump of new viruses, high population density and inadequate medical facilities. In this short review we have highlighted the risk factors and transmission dynamics of coronaviruses that may pose a serious threat to India. We have also discussed about the possible preventive measure our country should take to control any such outbreak situation.

3.
Curr HIV Res ; 16(4): 315-320, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30338741

RESUMO

BACKGROUND AND OBJECTIVES: People living with HIV/AIDS are at an increased risk of developing cancer. The goals of this study were to obtain data on the prevalence of HIV in the cancer population and vice versa at a major tertiary cancer and HIV center in North India. METHODS: This cross-sectional study was conducted over a 3-year period from July 2013 to June 2016, wherein successive HIV positive patients from an anti-retroviral therapy (ART) center were screened for malignancy. Simultaneously, successive cancer patients at the cancer center were screened for HIV. Baseline demographic details, risk factors, and laboratory investigations were obtained for all the patients. RESULTS: Among the 999 HIV-positive patients at the ART center, the prevalence of malignancy was 2% (n=20; 95% confidence interval (CI) 1.13, 2.87). Among the 998 patients with a malignancy, the prevalence of HIV infection was 0.9% (n=9; 95% CI 0.31, 1.49). Weight loss, loss of appetite, and fever were the most common symptoms in patients with HIV and cancer. Among 29 patients with HIV and cancer, AIDS-defining cancer was found in 19 patients; non-Hodgkin's lymphoma was the most common malignancy reported (n=13). INTERPRETATION AND CONCLUSION: There is a low prevalence of HIV in cancer patients as well as a low prevalence of cancer in HIV patients. AIDS-defining cancers remain much more common than non-AIDS-defining cancers. With the increased coverage of ART, it is expected that non-AIDSdefining cancers will increase, as is evident from data from more developed countries.


Assuntos
Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Neoplasias/complicações , Neoplasias/epidemiologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Centros de Atenção Terciária
4.
Infect Dis (Auckl) ; 11: 1178633718788870, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30046244

RESUMO

BACKGROUND: Emergence of human immunodeficiency virus (HIV) drug resistance mutations prior to highly active antiretroviral therapy is a serious problem in clinical management of HIV/AIDS. Risk factors for appearance of drug resistance mutations are not known. We hypothesize that Mycobacterium tuberculosis infection may contribute to rapid emergence of such mutations in antiretroviral therapy-naïve patients. METHODS: A total of 115 patients were recruited in this study of which 75 were HIV+TB+ coinfected (group 1) and 40 were HIV+TB- (group 2). Blood samples from all the patients were collected and CD4+ cell counts; HIV-1 plasma viral load and sequencing of protease and two-third region of reverse transcriptase of HIV-1 was performed and analyzed for drug resistance pattern. RESULTS: For patients with HIV+TB+, 10.6% (8/75) had mutations to non-nucleoside reverse transcriptase inhibitors (NNRTIs), 4% (3/75) to nucleoside reverse transcriptase inhibitors, and only 2.6% (2/75) patients had mutations to protease inhibitors. Interestingly, for group 2 (HIV+TB-), there were only NNRTI mutations found among these patients, and only 3 patients (7.5%) had these drug-resistant mutations. Clade typing and phylogenetic tree analysis showed HIV-1 subtype C predominance in these patients. CONCLUSIONS: Our study showed that higher percentage of HIV drug resistance mutations was found among HIV+TB+ individuals compared with tuberculosis-uninfected patients. Tuberculosis coinfection may be a risk factor for emergence of high frequency of drug resistance mutations. Studies with a larger sample size will help to confirm these findings from the Indian population.

5.
Curr HIV Res ; 16(2): 167-173, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29807518

RESUMO

BACKGROUND: Vitamin D is an immunomodulator, and its deficiency is associated with Tuberculosis (TB) infection. Bronchoalveolar lavage fluid (BALF) is a rich milieu of macrophages that form the first line of defense against invading TB bacilli. As there is an increased prevalence of vitamin D deficiency in TB and human immunodeficiency virus-1 (HIV-1) subjects, we intend exploring the possibility of a localized deficiency of vitamin D metabolites in BALF of these patients. OBJECTIVE: The primary objective was to assess the level of 25D3 in serum and BALF of subjects and look for a significant difference among patients and controls. The secondary objective was to find a correlation between serum and BALF 25D3 levels. METHODS: We performed a cross-sectional study with subjects divided into four groups: Controls (group 1), HIV positive without active TB (group 2), active TB without HIV (group 3), and HIV-TB coinfection (group 4). BALF and serum 25D3 levels were compared between the groups. RESULTS: Among the 149 (an immunomodulator) successive subjects enrolled, there were 40 subjects in group 1 (HIV-TB-), 48 in group 2 (HIV+TB-), 37 in group 3 (HIV-TB+), and 24 in group 4 (HIV+TB+). Females constituted 31.6% of the study subjects. In groups 3 and 4, there were significantly lower serum 25D3 levels compared to group 1 (p-value group 3: 0.002; group 4: 0.012). In groups 2, 3, and 4, there were significantly lower BALF 25D3 levels compared to group 1 (p-value group 2: 0.000; group 3: 0.000; group 4: 0.001). There was a significant correlation between serum and BALF 25D3 levels (Spearman's rank correlation coefficient 0.318, p-value = 0.0001). CONCLUSION: Lower levels of serum and BALF 25D3 were observed in HIV, TB, and HIV-TB coinfected patients. Localized deficiency of vitamin D metabolites might be associated with increased vulnerability to TB infection.


Assuntos
Líquido da Lavagem Broncoalveolar , Calcifediol/metabolismo , Infecções por HIV/epidemiologia , Infecções por HIV/metabolismo , Tuberculose/epidemiologia , Adulto , Biomarcadores , Contagem de Linfócito CD4 , Calcifediol/sangue , Coinfecção , Estudos Transversais , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Centros de Atenção Terciária
6.
J Virol ; 84(24): 12790-800, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20926575

RESUMO

HIV-1 RNA undergoes a complex splicing process whereby over 40 different mRNA species are produced by alternative splicing. In addition, approximately half of the RNA transcripts remain unspliced and either are used to encode Gag and Gag-Pol proteins or are packaged into virions as genomic RNA. It has previously been shown that HIV-1 splicing is regulated by cis elements that bind to cellular factors. These factors either enhance or repress definition of exons that are flanked by the HIV-1 3' splice sites. Here we report that expression of modified U1 snRNPs with increased affinity to HIV-1 downstream 5' splice sites and to sequences within the first tat coding exon act to selectively increase splicing at the upstream 3' splice sites in cotransfected 293T cells. This results in a decrease of unspliced viral RNA levels and an approximately 10-fold decrease in virus production. In addition, excessive splicing of viral RNA is concomitant with a striking reduction in the relative amounts of Gag processing intermediates and products. We also show that T cell lines expressing modified U1 snRNAs exhibit reduced HIV-1 replication. Our results suggest that induction of excessive HIV-1 RNA splicing may be a novel strategy to inhibit virus replication in human patients.


Assuntos
Processamento Alternativo , Infecções por HIV/genética , HIV-1/fisiologia , RNA Nuclear Pequeno/genética , RNA Viral/genética , Replicação Viral/fisiologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Northern Blotting , Western Blotting , Células Cultivadas , Regulação Viral da Expressão Gênica , Infecções por HIV/virologia , Humanos , Sítios de Splice de RNA/fisiologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/metabolismo , Linfócitos T/virologia
7.
J Virol ; 83(12): 6067-78, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19357165

RESUMO

The human immunodeficiency virus type 1 (HIV-1) accessory protein Vif is encoded by an incompletely spliced mRNA resulting from splicing of the major splice donor in the HIV-1 genome, 5' splice site (5'ss) D1, to the first splice acceptor, 3'ss A1. We have shown previously that splicing of HIV-1 vif mRNA is tightly regulated by suboptimal 5'ss D2, which is 50 nucleotides downstream of 3'ss A1; a GGGG silencer motif proximal to 5'ss D2; and an SRp75-dependent exonic splicing enhancer (ESEVif). In agreement with the exon definition hypothesis, mutations within 5'ss D2 that are predicted to increase or decrease U1 snRNP binding affinity increase or decrease the usage of 3'ss A1 (D2-up and D2-down mutants, respectively). In this report, the importance of 5'ss D2 and ESEVif for avoiding restriction of HIV-1 by APOBEC3G (A3G) was determined by testing the infectivities of a panel of mutant viruses expressing different levels of Vif. The replication of D2-down and ESEVif mutants in permissive CEM-SS cells was not significantly different from that of wild-type HIV-1. Mutants that expressed Vif in 293T cells at levels greater than 10% of that of the wild type replicated similarly to the wild type in H9 cells, and Vif levels as low as 4% were affected only modestly in H9 cells. This is in contrast to Vif-deleted HIV-1, whose replication in H9 cells was completely inhibited. To test whether elevated levels of A3G inhibit replication of D2-down and ESEVif mutants relative to wild-type virus replication, a Tet-off Jurkat T-cell line that expressed approximately 15-fold-higher levels of A3G than control Tet-off cells was generated. Under these conditions, the fitness of all D2-down mutant viruses was reduced relative to that of wild-type HIV-1, and the extent of inhibition was correlated with the level of Vif expression. The replication of an ESEVif mutant was also inhibited only at higher levels of A3G. Thus, wild-type 5'ss D2 and ESEVif are required for production of sufficient Vif to allow efficient HIV-1 replication in cells expressing relatively high levels of A3G.


Assuntos
Citidina Desaminase/metabolismo , Sítios de Splice de RNA , Splicing de RNA , RNA Viral/genética , Produtos do Gene vif do Vírus da Imunodeficiência Humana/metabolismo , Desaminase APOBEC-3G , Linhagem Celular , Regulação Viral da Expressão Gênica , HIV-1/genética , HIV-1/fisiologia , Humanos , Mutação , Replicação Viral
8.
Methods Mol Biol ; 485: 73-85, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19020819

RESUMO

The unintegrated viral DNA synthesized during human immunodeficiency virus type 1 infection includes linear and circular forms. Circular forms of viral DNA are surrogate markers for nuclear import of viral DNA during virus replication as well as events surrounding the completion of reverse transcription. Analysis of 2-LTR circles is convenient and the quantity of 2-LTR circle formed is directly proportional to the amount of viral DNA imported into the cell nucleus. In addition, correct synthesis of 2-LTR circles is an outcome of HIV-1 Gag-Pol function. Thus, quantitation and sequence analysis of 2-LTR circles have been very important in studying the structure and function relationship of key viral proteins. In this chapter, we describe the methods of quantitation and analysis of 2-LTR circle junctions isolated from HIV-1 infected cells.


Assuntos
DNA Circular/análise , DNA Circular/genética , DNA Viral/análise , DNA Viral/genética , Repetição Terminal Longa de HIV/genética , HIV-1/genética , Linhagem Celular , HIV-1/fisiologia , Humanos , Linfócitos T/química , Linfócitos T/virologia , Replicação Viral/fisiologia
9.
J Virol ; 82(3): 1600-4, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18032510

RESUMO

We have previously described several human immunodeficiency virus type 1 (HIV-1) mutants that are characterized by an excessive-RNA-splicing phenotype and reduced virus particle production. In one of these mutants (NLD2up), the sequence of 5' splice site D2 was changed to a consensus splice donor site. This splice site overlaps the HIV-1 integrase reading frame, and thus, the NLD2up mutant also bears a G-to-W change at amino acid 247 of the integrase. A previously described E-to-K mutant at position 246 of the C-terminal domain of the integrase, which resulted in a G-to-A mutation at the +3 position of overlapping splice donor D2 (NLD2A3), was also shown to affect virus particle production and Gag protein processing. By using second-site mutations to revert the excessive-splicing phenotype, we show that the effects on Gag protein processing and virus particle production of both the NLD2up and NLD2A3 mutants are caused by excessive viral RNA splicing due to the activation of the overlapping 5' splice site and not to the changes in the integrase protein. Both integrase protein mutations, however, are lethal for virus infectivity. These studies suggest that changes in the usage of overlapping splice sites may be a possible alternative explanation for a defective virus phenotype resulting from changes in protein-coding sequences or in the nucleotide sequence during codon optimization.


Assuntos
Processamento Alternativo , Substituição de Aminoácidos , Integrase de HIV/metabolismo , HIV-1/genética , Replicação Viral , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Integrase de HIV/genética , HIV-1/metabolismo , Humanos , RNA Viral/genética , RNA Viral/metabolismo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
10.
Nucleic Acids Res ; 34(10): 2853-63, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16723431

RESUMO

We reported previously that substitutions F61L, F61W, F61Y and F61A in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase affect strand displacement synthesis [T. S. Fisher, T. Darden and V. R. Prasad (2003) J. Mol. Biol., 325, 443-459]. We have now determined the effect of these mutations on HIV replication. All mutant viruses were replication defective. Measuring replication intermediates in infected cells did not reveal a specific block as all mutants displayed reduced DNA synthesis (wild-type>F61L>F61W>F61Y>F61A). Analysis of 2-LTR circle junctions revealed that F61W and F61Y mutants generated increased aberrant circle junctions. Circle junctions corresponding to F61Y included 3'-PPT insertions suggesting ribonuclease H defect. In vitro assays mimicking PPT primer generation indicated that F61L, F61W and F61Y mutant RTs were unaffected, while F61A mutant cleaved both at PPT/U3 junction and at +6 with similar efficiencies. In assays measuring cleavage at the RNA/DNA junction to remove the PPT primer, all mutants were significantly affected with F61Y and F61A being most severely impaired. Our results show that (i) replication block of most mutants is due to more than one biochemical defect; (ii) mutations in polymerase domain can affect the function of a distal domain; and (iii) virological analyses of RT mutations can yield insight into structure-function relationship that is otherwise not obvious.


Assuntos
Transcriptase Reversa do HIV/genética , HIV-1/enzimologia , HIV-1/genética , Ribonuclease H/metabolismo , Replicação Viral , Substituição de Aminoácidos , Linhagem Celular Tumoral , Primers do DNA , Replicação do DNA , DNA Viral/biossíntese , DNA Viral/química , Repetição Terminal Longa de HIV , Transcriptase Reversa do HIV/química , Transcriptase Reversa do HIV/metabolismo , HIV-1/fisiologia , Humanos , Fenilalanina/genética , Transcrição Reversa , Análise de Sequência de DNA
11.
AIDS Res Hum Retroviruses ; 18(16): 1219-27, 2002 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-12494921

RESUMO

Genetic subtyping has been a powerful tool in tracking the global spread of HIV. To determine the HIV-1 subtypes circulating in eastern and northeastern regions of India blood samples were collected from female sex workers in Calcutta and intravenous drug users (IDUs) in Manipur. Fifty-four samples from Calcutta and 25 samples from Manipur were analyzed for HIV-1 subtyping by heteroduplex mobility assay (HMA). Twenty-six samples from these regions were sequenced. HMA and sequencing of the samples from these regions revealed subtype C as the major subtype, circulating within both eastern and northeastern regions. In Manipur, subtype ThaiB was also detected as the second major subtype. Some of the IDUs from Manipur were found to be dual infected with subtype C and ThaiB.


Assuntos
HIV-1/classificação , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Produtos do Gene env/química , HIV-1/genética , Humanos , Índia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
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