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1.
South Asian J Cancer ; 7(2): 69-71, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29721466

RESUMO

Magnetic resonance imaging (MRI) of the breast is primarily used as a supplemental tool to breast screening with mammography or ultrasound. A breast MRI is mainly used for women who have been diagnosed with breast cancer, to help measure the size of the cancer, look for other tumors in the breast, and to check for tumors in the opposite breast. For certain women at high risk for breast cancer, a screening MRI is recommended along with a yearly mammogram. MRI is known to give some false positive results which mean more test and/or biopsies for the patient. Thus, although breast MRI is useful for women at high risk, it is rarely recommended as a screening test for women at average risk of breast cancer. Also, breast MRI does not show calcium deposits, known as micro-calcifications which can be a sign of breast cancer.

2.
J Gen Virol ; 98(5): 962-976, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28221101

RESUMO

Hepatitis C virus (HCV) is a leading cause of chronic viral hepatitis, but an effective vaccine is still not available to prevent infection. Use of neutralizing antibodies could be a potential therapeutic option. In this study, the presence of anti-HCV antibodies in HCV-infected patients was assessed from 50 patients and the presence of neutralizing antibodies was examined using 'hepatitis C virus-like particles'. Antibodies from two samples exhibited significant inhibitory activity, suggesting that these may neutralize viral infection. Antigenic determinants generating the neutralizing antibodies from these two samples were delineated by epitope mapping using the core, E1 and E2 regions and a stretch of 45 amino acid peptide (E2C45) derived from the C-terminal region of HCV-E2 protein (aa 634-679) was designed. Results suggest that this hitherto uncharacterized region has the potential to generate neutralizing antibodies against HCV and thus be effective in preventing virus entry into liver cells. Computational analysis of the structure of the modelled peptide (E2C45) suggested high conformational entropy for this region. Furthermore, E2C45 peptide-generated antibodies could block virus entry and monoclonal antibodies generated against this peptide could also significantly reduce virus replication in a cell culture system. It is possible that the inhibition could be partly due to a conformational alteration of the CD81-binding region, preventing virus attachment to liver cells. In conclusion, this work focused on the discovery of a novel epitope at the C terminus of E2 that induces potent neutralizing antibodies in HCV-infected patients.


Assuntos
Anticorpos Neutralizantes/sangue , Reações Cruzadas , Epitopos/imunologia , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Linhagem Celular , Mapeamento de Epitopos , Epitopos/química , Hepacivirus/fisiologia , Anticorpos Anti-Hepatite C/imunologia , Hepatócitos/virologia , Humanos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Conformação Proteica , Proteínas do Envelope Viral/química , Internalização do Vírus/efeitos dos fármacos
3.
J Gen Virol ; 95(Pt 8): 1654-1667, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24784414

RESUMO

Persistent infection of hepatitis C virus (HCV) can lead to liver cirrhosis and hepatocellular carcinoma, which are currently diagnosed by invasive liver biopsy. Approximately 15-20 % of cases of chronic liver diseases in India are caused by HCV infection. In North India, genotype 3 is predominant, whereas genotype 1 is predominant in southern parts of India. The aim of this study was to identify differentially regulated serum proteins in HCV-infected Indian patients (genotypes 1 and 3) using a two-dimensional electrophoresis approach. We identified eight differentially expressed proteins by MS. Expression levels of one of the highly upregulated proteins, retinol-binding protein 4 (RBP4), was validated by ELISA and Western blotting in two independent cohorts. We also confirmed our observation in the JFH1 infectious cell culture system. Interestingly, the HCV core protein enhanced RBP4 levels and partial knockdown of RBP4 had a positive impact on HCV replication, suggesting a possible role for this cellular protein in regulating HCV infection. Analysis of RBP4-interacting partners using a bioinformatic approach revealed novel insights into the possible involvement of RBP4 in HCV-induced pathogenesis. Taken together, this study provided information on the proteome profile of the HCV-infected Indian population, and revealed a link between HCV infection, RBP4 and insulin resistance.


Assuntos
Hepatite C Crônica/imunologia , Proteoma/análise , Proteínas Plasmáticas de Ligação ao Retinol/análise , Soro/química , Adulto , Idoso , Western Blotting , Eletroforese em Gel Bidimensional , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Índia , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade
4.
Sci Rep ; 3: 1555, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23549102

RESUMO

Changes in circulating miRNA profiles have been associated with different diseases. Here we demonstrate the circulating miRNA profile in serum of HCV infected individuals using a microRNA array that profiles the expression of 940 miRNAs. Serum samples from two HCV genotype - 1 and two HCV genotype - 3 infected individuals were compared with healthy controls. Expression levels of miR-134, miR-198, miR-320c and miR-483-5p that were commonly upregulated in case of both genotypes were validated in 36 individual patient serum samples. Serum miR-134, miR-320c and miR-483-5p were significantly upregulated during HCV infection. miR-320c and miR-483-5p were also upregulated in HCV- JFH1 infected cells and cell culture supernatant. Pathway analysis of putative target genes of these miRNAs indicated involvement of PI3K-Akt, NFKB and MAPK signaling pathways. Results revealed novel insights on the role of circulating miRNAs in mediating pathogenesis in HCV-infected cells.


Assuntos
Hepacivirus/genética , Hepacivirus/patogenicidade , Hepatite C/sangue , Hepatite C/virologia , MicroRNAs/sangue , MicroRNAs/genética , Transdução de Sinais/genética , Hepatite C/genética , Humanos , MicroRNAs/isolamento & purificação
5.
Indian J Hum Genet ; 17(1): 17-21, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21814338

RESUMO

INTRODUCTION: Designing a rapid, reliable and sensitive assay for detection of hepatitis B virus (HBV) variants by real-time PCR is challenging at best. A recent approach for quantifying the viral load using a sensitive fluorescent principle was brushed in this study. MATERIALS AND METHODS: : A total of 250 samples were collected from the outpatient unit, CLRD. Complete Human HBVDNA sequences (n = 944) were selected from the National Centre for Biotechnology Information (NCBI), primers and probes were designed and synthesized from the core, surface, and x region. Real-time based quantification was carried out using a standard kit and in-house generated standards and RT-PCR protocols. RESULTS AND DISCUSSION: The standard calibration curve was generated by using serial dilution 10(2) to 10(8). The calibration curve was linear in a range from 10(2) to 10(8) copies/ml, with an R(2) value of 0.999. Reproducibility as measured by dual testing of triplicates of serum samples was acceptable, with coefficients of variation at 6.5%, 7.5%, and 10.5%. Our results showed that amplification performance was good in the case of the x-region-based design (98%). Out of 100 negative samples screened by enzyme linked immunosorbent assay and the standard RT-PCR kit, one sample was detected as positive with the in-house developed RT-PCR assay, the positivity of the sample was confirmed by sequencing the amplified product, NCBI accession EU684022. CONCLUSION: This assay is reproducible showing limited inter- and intra-assay variability. We demonstrate that the results of our assay correlated well with the standard kit for the HBV viral load monitor.

6.
Infect Genet Evol ; 7(6): 724-30, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17540621

RESUMO

Hepatitis C virus shows substantial nucleotide sequence diversity distributed throughout the viral genome. In the present study genotyping for Hepatitis C virus (HCV) infected patients was based on RFLP analysis of 5' UTR and using type specific primers of NS5B regions. It was observed that 60% of the patients (30 patients with chronic hepatitis) were infected with variants of genotype 1 and 40% of the patients (4 chronic hepatitis patients, 12 patients with chronic renal failure and 4 cirrhosis) were infected with variants of type 3 of HCV. None of the cirrhotic patients and patients with chronic renal failure, in the present study, were infected with type 1 of HCV. While PCR-RFLP, typing was rapid in conjunction with the primers used for RT-PCR, NS5 typing was helpful in determining the subtype. There was good correlation between the two typing methods and this method can be used as a cost-effective method for studying large number of samples. The study shows that predominant genotypes of HCV in South India include type 1 and 3. Type 3 seems to be transmitted nosocomially as suggested by the results in patients with chronic renal failure, as these patients are exposed to multiple medical interventions.


Assuntos
Hepacivirus/genética , Hepatite C/virologia , Regiões 5' não Traduzidas , Adulto , Sequência de Bases , Primers do DNA , Feminino , Genótipo , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas não Estruturais Virais/genética
7.
J Clin Virol ; 37(1): 58-64, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16846749

RESUMO

BACKGROUND: Genotypes or genetic subtypes describe genetically related strains and have been described for viruses belonging to several different families. The eight major genotypes of hepatitis B virus (HBV) have distinct geographic distribution. Recent studies suggest possible pathogenic and therapeutic differences among HBV genotypes. OBJECTIVES: To evaluate the HBV genotypes of 85 samples by RFLP analysis and sequence the desired region to look for variations and identify the subtypes of the surface region. STUDY DESIGN: We studied 85 patients with HBV in order to identify the most prevalent genotype and subtype. Patients with HBV-related liver disease attending the Department of Gastroenterology at Owaisi Hospital and Research Centre were studied. RESULTS AND CONCLUSIONS: Genotype D1 was most prevalent. Genotyping was carried out by RFLP analysis and confirmed by sequencing. Nucleotide sequences showed significant homology (96-97%) with the other genotypes that have been reported. Subtype ayw was the most prevalent subtype within the surface region. Construction of a phylogenetic tree incorporating these isolates and other published HBV sequences showed that the isolates are derived from the same evolutionary tree. The study adds to our understanding of the genetic diversity of HBV and the geographical distribution of its subtypes, and will be useful for reconstructing the evolutionary history of HBV.


Assuntos
Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B/virologia , Adulto , Análise por Conglomerados , Impressões Digitais de DNA , DNA Viral/genética , Evolução Molecular , Feminino , Genótipo , Geografia , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
8.
Intervirology ; 47(6): 374-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15564751

RESUMO

The present study reports prevalence of posttransplant hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in 256 patients with chronic renal failure (CRF) and with a history of either renal transplant or hemodialysis. Out of 256 patients 138 had renal transplant and 118 were on maintenance hemodialysis. Among the patients screened, 7% had HBV infection alone, 46% were infected with HCV alone, while 37.10% were found to have co-infection of both the viruses. Our findings implicate these viruses as the major cause of posttransplant hepatitis in Indian patients with CRF and indicate implementation of stringent screening procedures for these two viral infections.


Assuntos
Hepatite B Crônica/epidemiologia , Hepatite C Crônica/epidemiologia , Falência Renal Crônica/complicações , DNA Viral/análise , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Humanos , Índia/epidemiologia , Falência Renal Crônica/terapia , Transplante de Rim/efeitos adversos , Prevalência , Diálise Renal , Transplante Homólogo
9.
Trop Gastroenterol ; 24(4): 193-5, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15164530

RESUMO

Viral hepatitis caused by the hepatitis C virus (HCV) and hepatitis B virus (HBV) represents a major public health problem in India. These viruses share common modes of transmission, such as parenteral routes. We aimed to assess the exposure of a tribal population to these viruses in south India. The present study was carried out on serum samples from 890 individuals (526 males and 324 females) belonging to the Lambada tribe residing in the state of Andhra Pradesh, south India. Anti-HCV antibody and hepatitis B surface antigen (HBsAg) status in the sera were analyzed using commercially available enzyme immunoassays (Abbott Labs, Chicago, IL). HCV-RNA and HBV-DNA in the sera was tested by reverse transcriptase polymerase chain reaction (RT-PCR) and PCR, respectively. The infecting genotype of HCV was determined using type-specific primers corresponding to the NS5 region of the virus. Out of the 890 samples, 18 (2.02%; male 11/526; female 7/364) were positive for HCV-RNA by RT-PCR and, 17 of them were positive for anti-HCV antibody. Genotyping of HCV isolates from the 18 individuals positive for HCV-RNA revealed that 66.67% (12/18) were infected with type 1 of HCV and its variants; while in the remaining (6/18), the infecting genotype was found to be type 3 and its variants. A total of 46 samples (5.16%; males 28/526; female 18/364) were positive for HBsAg; while 11 were positive only for HBV-DNA, 9 were positive for both hepatitis B e antigen (HBeAg) and HBV-DNA. Cultural practices such as tattooing, traditional medicine (e.g. blood-letting), rituals (e.g. scarification), body-piercing etc are the potential sources of spread of infection in this tribe. None of the samples analyzed revealed co-infection with the 2 viruses.


Assuntos
Hepacivirus/genética , Vírus da Hepatite B/genética , Hepatite B/etnologia , Hepatite C/etnologia , Adolescente , Adulto , Idoso , Criança , Feminino , Genótipo , Hepatite B/virologia , Hepatite C/virologia , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Grupos Populacionais/estatística & dados numéricos , Prevalência , Fatores de Risco
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