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1.
J Med Virol ; 93(6): 3656-3665, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32975838

RESUMO

Fulminant hepatic failure (FHF) is a lethal manifestation of hepatitis A virus (HAV) infection, whose underlying mechanisms are poorly understood. We aimed to evaluate the importance of the modulation of the RANTES-chemokine receptor type 5 (CCR5) signaling axis and its immunomodulatory effects in directing hepatitis A disease pathogenesis using an in silico, in vitro and patient cohort-based approach. In silico interaction studies were performed using computation approaches with suitable software. Differential expression of relevant cytokines and immune cell markers were studied using real-time quantitative reverse transcription PCR (qRT-PCR), enzyme-linked immunosorbent assay, and flow-cytometry-based methods. In the HepG2 cell line, we studied inflammatory responses and susceptibility to HAV infection following RANTES stimulation and antibody blockade of CCR5. The HAV-VP3 region exhibited high interaction in CCR5: HAV complexes. RANTES levels were significantly increased in FHF cases. Reduced monocyte and T-cell activation were observed in FHF cases. RANTES expression inversely correlated with viremia but positively correlated with proinflammatory responses. Hyper Th1-biased immune responses, marked by high interleukin (IL)-12/IL-10 ratio were observed in FHF cases, which were also characterized by upregulated tumor necrosis factor-alpha (TNF-α) expression and reduced interferon-gamma expression. In vitro, RANTES was protective against HAV infection but resulted in upregulated TNF-α expression. Although viral load increased upon the regulation of inflammatory responses by CCR5 blocking, it was still significantly lower compared to control HAV-infected cells. Our study suggests the importance of RANTES-CCR5 signaling and linked-immunomodulation in HAV disease pathogenesis, as well as highlights the utility of CCR5 antagonists as a risk-reduction strategy in FHF patients. Our findings, therefore, have important implications for the management of high-risk HAV infections.


Assuntos
Quimiocina CCL5/genética , Quimiocina CCL5/imunologia , Vírus da Hepatite A/imunologia , Hepatite A/imunologia , Receptores CCR5/genética , Receptores CCR5/imunologia , Adulto , Quimiocina CCL5/farmacologia , Estudos de Coortes , Simulação por Computador , Feminino , Células Hep G2 , Hepatite A/virologia , Hepatócitos/efeitos dos fármacos , Humanos , Imunomodulação , Falência Hepática Aguda , Masculino , Pessoa de Meia-Idade , Prognóstico , Carga Viral
2.
Indian J Pharmacol ; 51(3): 214-221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31391689

RESUMO

Advancements in the field of biomedical and health research pose new ethical challenges warranting the need for constant updation in the existing ethics guidance. Realizing this, revision of "Ethical Guidelines for Biomedical Research on Human Participants (2006)" was initiated in the year 2015. The preparation of guidelines was a participatory process involving large number of stakeholders from various backgrounds in order to get a variety of perspectives. The initial draft went through an extensive process of consultation at both regional and national level, with experts and stakeholders from academia, govt. agencies, departments and ministries, public and private institutions, pharmaceutical industry, non-governmental organizations, patient organizations, regulators, international agencies as well as with public. The revised "National Ethical Guidelines for Biomedical and Health Research Involving Human Participants, 2017" were released on October 12, 2017, and address ethical concerns, in accordance to the sociocultural milieu of our country. New sections have been added on informed consent process, vulnerability, biological materials, biobanking and datasets, responsible conduct of research, sociobehavioral research, research in emergencies or disasters. The revised guidelines must be followed by all stakeholders who are engaged in biomedical and health research including sponsors, institutions, ethics committees, and researchers. It is expected that the implementation of these guidelines would help to protect the dignity, rights, safety and well-being of research participants and also to improve the quality of biomedical and health research.


Assuntos
Pesquisa Biomédica/ética , Guias como Assunto , Bancos de Espécimes Biológicos , Ensaios Clínicos como Assunto , Desastres , Ética em Pesquisa , Testes Genéticos , Humanos , Índia , Consentimento Livre e Esclarecido
3.
Indian J Gastroenterol ; 37(4): 293-298, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30109600

RESUMO

BACKGROUND: The level of inflammatory cytokine Interleukin (IL)-10 is increased in patients infected with hepatitis-related acute liver failure (ALF), and this was thought to be because of the regulatory polymorphism in the IL-10 gene promoter region. The present study was designed to analyze the possible association between IL-10 gene promoter polymorphism and acute viral hepatitis (AVH), and ALF. An attempt was made to quantify IL-10 levels at admission, during the hospital stay, and at the final outcome to study its relationship with liver injury among patients with AVH, ALF, and controls. METHODS: The study included 40 patients each with ALF and AVH. IL-10 gene promoter polymorphism was detected by the PCR-RFLP method. Quantification of IL-10 was done using commercially available ELISA kits. RESULTS: The individuals with -592 AC, -819 TC, -1082 AA genotypes were found to have a significantly higher risk of ALF whereas those with -592 AA and - 819 CC polymorphism were found to be less susceptible. Individuals with - 819 CC were found to be more susceptible to AVH while those with -592 AA and -819 TT were less susceptible as compared to controls. Mean serum IL-10 at admission was significantly elevated in patients with ALF (38.4±11.3 pg/mL) as compared to patients with AVH (16.7±5.4 pg/mL) and control population (8.3±3.6 pg/mL, p < 0.05). CONCLUSION: Regulatory polymorphism in the IL-10 gene promoter has a possible and significant association with severity and outcome in patients with AVH and ALF. Raised levels of IL-10 could be predictive of prognosis in patients with ALF.


Assuntos
Estudos de Associação Genética , Hepatite Viral Humana/genética , Interleucina-10/genética , Falência Hepática Aguda/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Doença Aguda , Ensaio de Imunoadsorção Enzimática , Genótipo , Humanos , Interleucina-10/sangue , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Valor Preditivo dos Testes , Prognóstico , Risco , Índice de Gravidade de Doença
4.
J Gen Virol ; 95(Pt 6): 1266-1271, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24622580

RESUMO

The incidence and severity of hepatitis E virus (HEV) infection in pregnant women is high in developing countries. Transplacental transmission of HEV in the third trimester of pregnancy has been found to be associated with high fetal mortality. Based on this evidence and in the absence of reports on HEV replication in extrahepatic sites, this study was carried out to investigate if HEV replication occurs in the placenta of infected mothers. The study included 68 acute viral hepatitis (AVH) and 22 acute liver failure (ALF) pregnant patients. Viral RNA was extracted from blood and placenta. HEV replication in placenta was confirmed by a replicative negative-strand-specific reverse transcriptase PCR. Viral load was estimated by real-time PCR. Immunohistochemical studies were also carried out for in situ detection of HEV in placental tissue sections. Replicative HEV RNA was detectable only in the placenta in ALF and AVH cases and not in blood samples. Positive staining of placental tissue sections with HEV antibody against the viral structural protein ORF3 was observed. HEV replication in placenta also correlated with fetal and maternal mortality in ALF patients. It is demonstrated for the first time that HEV replication occurs in human placenta and that placenta may be a site of extrahepatic replication of HEV in humans.


Assuntos
Vírus da Hepatite E/fisiologia , Vírus da Hepatite E/patogenicidade , Hepatite E/complicações , Hepatite E/virologia , Placenta/virologia , Complicações Infecciosas na Gravidez/virologia , Doença Aguda , Antígenos Virais/metabolismo , Países em Desenvolvimento , Feminino , Hepatite E/transmissão , Vírus da Hepatite E/genética , Humanos , Imuno-Histoquímica , Índia , Transmissão Vertical de Doenças Infecciosas , Fígado/virologia , Falência Hepática Aguda/complicações , Falência Hepática Aguda/virologia , Gravidez , RNA Viral/sangue , RNA Viral/genética , RNA Viral/isolamento & purificação , Carga Viral , Replicação Viral
5.
J Med Virol ; 85(4): 620-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23280991

RESUMO

The incidence and mortality in pregnant women with acute liver failure caused by hepatitis E virus (HEV) is high. Data on the viral load of HEV during pregnancy are limited. The study was designed to determine the viral load of HEV and its association with the disease severity in patients with acute liver failure. A total of HEV related 163 patients with acute liver failure which included 105 pregnant, 46 non-pregnant women and girls and 12 men and 730 patients with acute viral hepatitis which comprised of 220 pregnant women; 282 non-pregnant women and girls and 228 men were included. Viral load was measured by real-time PCR. Comparison was made between the pregnant and non-pregnant women. HEV RNA was detectable in 265 patients (142 pregnant; 75 non-pregnant and 48 men) and 104 patients with acute liver failure (64 pregnant, 34 non-pregnant and 6 men). The viral load of HEV in pregnant women with acute liver failure and acute viral hepatitis was significantly higher 129,984.0 ± 103,104.17 and 768.92 ± 1,105.40 copies/ml, respectively compared to the non-pregnant women which was 189.2 ± 225 and 12.73 ± 7.8 copies/ml (P < 0.0001). The viral load of HEV was also significantly higher in the pregnant patients with acute liver failure compared to the pregnant women with acute viral hepatitis and also men (P < 0.0001). High viral load of HEV during pregnancy could be one of the factors responsible for the severity of the infection during pregnancy.


Assuntos
Vírus da Hepatite E/isolamento & purificação , Hepatite E/complicações , Hepatite E/virologia , Falência Hepática Aguda/diagnóstico , Complicações Infecciosas na Gravidez/virologia , Índice de Gravidade de Doença , Carga Viral , Adolescente , Adulto , Criança , Feminino , Hepatite E/patologia , Humanos , Falência Hepática Aguda/virologia , Masculino , Pessoa de Meia-Idade , Gravidez , Complicações Infecciosas na Gravidez/patologia , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
6.
Arch Virol ; 155(8): 1227-33, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20532928

RESUMO

Hepatitis E virus infection is one of the major causes of hepatitis and has been responsible for many sporadic waterborne hepatitis epidemics. We studied 141 cases of viral hepatitis in the Gokulpuri area and collected the tap water, sewage water and serum samples from the individual cases of hepatitis in the community. Samples were analysed for the presence of hepatitis E virus (HEV) by RT-PCR, followed by sequencing. Forty-one out of 141 (29.08%) cases of viral hepatitis had evidence of HEV infection, detected by serology and/or RT-PCR. Six out of 141 (4.25%) sewage samples and 2 out of 141 (1.42%) drinking water samples were found to be positive for HEV RNA. The HEV isolates belonged to genotype 1. Evidence of HEV infection in sewage and drinking water samples indicates contamination of drinking water with sewage; good sanitary practice still remains a subject of alarm in the subcontinent.


Assuntos
Água Doce/virologia , Vírus da Hepatite E , Hepatite E , Vigilância da População/métodos , Esgotos/virologia , Abastecimento de Água , Adolescente , Adulto , Feminino , Anticorpos Anti-Hepatite/sangue , Hepatite E/diagnóstico , Hepatite E/epidemiologia , Hepatite E/transmissão , Hepatite E/virologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/imunologia , Vírus da Hepatite E/isolamento & purificação , Humanos , Incidência , Índia/epidemiologia , Masculino , Reação em Cadeia da Polimerase , RNA Viral/análise , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Poluição da Água , Adulto Jovem
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