82 research outputs found
Hepatitis B virus X protein impedes the DNA repair via its association with transcription factor, TFIIH
<p>Abstract</p> <p>Background</p> <p>Hepatitis B virus (HBV) infections play an important role in the development of hepatocellular carcinoma (HCC). HBV X protein (HBx) is a multifunctional protein that can modulate various cellular processes and plays a crucial role in the pathogenesis of HCC. HBx is known to interact with DNA helicase components of TFIIH, a basal transcriptional factor and an integral component of DNA excision repair.</p> <p>Results</p> <p>In this study, the functional relevance of this association was further investigated in the context to DNA repair. By site-directed mutagenesis HBx's critical residues for interaction with TFIIH were identified. Similarly, TFIIH mutants lacking ATPase domain and the conserved carboxyl-terminal domain failed to interact with HBx. Yeast and mammalian cells expressing HBx<sup>wt </sup>conferred hypersensitivity to UV irradiation, which is interpreted as a basic deficiency in nucleotide excision repair. HBx<sup>mut120 </sup>(Glu to Val) was defective in binding to TFIIH and failed to respond to UV.</p> <p>Conclusions</p> <p>We conclude that HBx may act as the promoting factor by inhibiting DNA repair causing DNA damage and accumulation of errors, thereby contributing to HCC development.</p
Prevalence and Genotyping of High Risk Human Papillomavirus in Cervical Cancer Samples from Punjab, Pakistan
Cervical cancer is the third most common cause of cancer-related death in women worldwide. Infection with high-risk human papillomavirus (HPV) is established as the cause of cervical carcinoma, therefore, high risk HPV detection may have prognostic significance for the women who are at increased risk of disease progression. The paucity of data on the incidence of cervical cancer in Pakistan makes it difficult to determine disease burden. Even less information is available regarding the prevalent HPV strains in cervical specimens collected from this region. Cervical cancer is a neglected disease in Pakistan in terms of screening, prevention, and vaccination. Identification and accurate genotyping of the virus burden in cancer specimens is important to inform intervention policies for future management of HPV associated disease and to potentially stratify patients dependent on HPV status. In this study, detection and genotyping of HPV types 16 and 18 from 77 cervical specimens were carried out. Consensus primers GP5+/GP6+, which detect 44 genital HPV types, and type specific primers (TS16 and TS18) were used in conjunction with newly designed type specific primers. Using a combination of these methods of detection, a total of 94.81% (95% CI ±4.95) of cervical lesions were positive for HPV. Single infections of HPV16 were detected in 24.68% (95% CI ±9.63) of total samples and HPV18 was found in 25.97% (95% CI ±9.79) samples. Interestingly, a high proportion of samples (40.26%, 95% CI ±10.95) was positive for both HPV16 and 18, indicating a higher incidence of co-infection than previously reported for similar ethnic regions. The HPV genotype of 3.90% of HPV positive samples remained undetected, although these samples were positive with the GP5+/GP6+ primer set indicating infection with an HPV type other than 16 or 18. These data indicate that the overall incidence of high risk HPV infection in cervical cancer and intraepithelial neoplasia specimens in Punjab, Pakistan is in line with the worldwide prevalence, but that the incidence of HPV16 and 18 co-infections in our cohort is higher than that previously reported
Hepatitis C Virus Infection: Molecular Pathways to Insulin resistance
Chronic Hepatitis C virus has the potential of inducing insulin resistance and type 2 Diabetes Mellitus in vitro as well as in vivo . Structural and non-structural proteins of HCV modulate cellular gene expression in such a way that insulin signaling is hampered, concomitantly leads toward diabetes mellitus. A number of mechanisms have been proposed in regard to the HCV induced insulin resistance involving the upregulation of Inflammatory cytokine TNF-α, hypophosphorylation of IRS-1 and IRS-2, phosphorylation of Akt, up-regulation of gluconeogenic genes, accumulation of lipids and targeting lipid storage organelles. This review provides an insight of molecular mechanisms by which HCV structural and non-structural proteins can induce insulin resistance
CHEMICAL COMPOSITION OF THE HEXANE EXTRACT OF LEAVES OF AZIMA TETRACANTHA (LAM)
Objective: In the present study, the phytochemical constituents of hexane extract from Azima tetracantha (AT) leaves were done by using Gas Chromatography Mass Spectrometry analysis technique (GC-MS). Azima tetracantha has been an important medicinal herb being used in tribal medicines since long, but chemical constituents of its bark responsible for the activities are still not studied in depth.Methods: Azima tetracantha leaves were collected from Ariyalur District, Tamil Nadu. The dried leaf was powdered and was extracted with the solvent hexane by using a Soxhlet apparatus. One microlitre of the extract was subjected to analysis by GC-MS to detect the presence of bioactive compounds present in the leaves of the plant.Results: The results showed that the leaves of Azima tetracantha contained 47 compounds, of which the major is n-hexadecanoic acid (39.10%) followed by oleic acid (11.54%). Analysis and identification of the presence of the compound in the extract were done by using the database of the National Institute of Standards and Technology (NIST) library.Conclusion: In the present study, 47 chemical constituents have been identified from the hexane leaf extract of Azima tetracantha by GC-MS analysis. The hexane extract is mainly composed of terpenoids and sterols. Thus, Azima tetracantha is found to possess significant phytonutrients, which attribute to its medicinal worth.Â
PREVALENT RISK FACTORS OF HCV TRANSMISSION IN HEALTH CARE WORKERS (HCWS) IN PAKISTAN
Objective: To study and analyze the prevalent risk factors of Hepatitis C Virus (HCV) transmission in Health Care Workers (HCWs) in PakistanMethods: A literature survey (2005-2012) was conducted from the available literatures to identify the most prominent risk factors and prevalence rate of HCV affected workers in Pakistan. Health care workers include doctors, nurses, paramedical staffs, dispensers, laboratory technicians and pharmacists. The most common risk factors associated with the high incidence rate of HCV in HCWs are lack of well-trained paramedical staff and their non-scientific behavior, improper disposal of hospital waste, lack of sterilization facilities, poor infrastructure, direct exposure to blood and its products and finally needle stick injury.Results: The mean prevalence of HCV in HCWs is 4.46%±2, with the highest prevalence (6%) in Islamabad and Rawalpindi area.Conclusion: We recommend for the HCWs to become aware of the possible risks of HCV spread and minimize the complications of hospital care. The government should have to initiate awareness program on HCV infection among health care professionals.Â
Identification of ionotrophic purinergic receptors in Huh-7 cells and their response towards structural proteins of HCV genotype 3a
Hepatitis C virus (HCV) is a major health problem in developing countries including Pakistan. Chronic HCV infection results in progressive liver disease including fibrosis, cirrhosis, insulin resistance and eventually hepatocellular carcinoma (HCC). Ionotrophic purinergic (P2X) receptors are identified to involve in a spectrum of physiological and pathophysiological processes. However, the role of P2X receptors in HCV liver associated diseases still remains to be investigated. The current study was designed to identify the presence of P2X receptors in human liver cells. Furthermore, it investigates the response of P2X receptors towards HCV structural proteins (E1E2). To determine that how many isoforms of P2X receptors are expressed in human liver cells, human hepatoma cell line (Huh-7) was used. Transcripts (mRNA) of five different isoforms of P2X receptors were identified in Huh-7 cells. To examine the gene expression of identified isoforms of P2X receptors in presence of HCV structural proteins E1E2, Huh-7/E1E2 cell line (stably expressing HCV structural proteins E1E2) was used. The results showed significant increase (6.2 fold) in gene expression of P2X4 receptors in Huh-7/E1E2 cells as compared to control Huh-7 cells. The findings of present study confirmed the presence of transcripts of five different isoforms of P2X receptors in human liver cells and suggest that P2X4 receptors could be represented an important component of the purinergic signaling complex in HCV induced liver pathogenesis
Role of Potash Alum in Hepatitis C virus Transmission at Barber's Shop
Hepatitis C virus (HCV) is the main cause of severe liver disease, including hepatocellular carcinoma, cirrhosis and end stage liver disease. In Pakistan most of HCV positive patients have history of facial/armpit shaving from barbers. 79% of barbers are rubbing Potash Alum stone on facial shaving cuts. Dark blood spots are analyzed on Potash Alum stones being used at different barber shops. The aim of the study was to check the viability of hepatitis C virus on potash alum stone being used at barber shops. Blood samples from HCV positive patients were taken and treated with 0.1, 0.2, 0.3, 0.4 and 0.5 molar concentrations of Potash Alum for different periods of time. Blood was centrifuged to isolate the serum; HCV RNA was extracted from serum and subjected to first strand synthesis and PCR. PCR fragments were confirmed by sequencing. PCR amplification was observed in all the samples, treated with different concentrations of Potash Alum, indicated that the virus remains alive on Potash Alum stone for a long period of time. Potash Alum being used by barbers on facial shaving cuts has definite role in HCV transmission in Pakistani population. Therefore use of Potash Alum stone should be banned on facial shaving cuts at barber shops
PCR-Based Molecular Diagnosis of Hepatitis Virus (HBV and HDV) in HCV Infected Patients and Their Biochemical Study
Seroprevalence of HCV indicates that HCV is found in more than 10% of HBV-or HDV-infected patients worldwide leading to liver disease. Here we show HBV and HDV coinfection association with HCV infected Pakistani patients, study of disease severity, and possible interpretation of associated risk factors in coinfected patients. A total of 730 liver diseased patients were included, out of which 501 were found positive for HCV infection via PCR. 5.1% of patients were coinfected with HBV while 1% were coinfected with HBV and HDV both. LFTs were significantly altered in dually and triply infected patients as compared to single HCV infection. Mean bilirubin, AST, and ALT levels were highest (3.25 mg/dL, 174 IU/L, and 348 IU/L) in patients with triple infection while dual infection LFTs (1.6 mg/dL, 61 IU/L, and 74 IU/L) were not high as in single infection (1.9 mg/dL, 76 IU/L, and 91 IU/L). The most prominent risk factor in case of single (22%) and dual infection (27%) group was "reuse of syringes" while in triple infection it was "intravenous drug users" (60%). It is concluded that HBV and HDV coinfections are strongly associated with HCV infected Pakistani patients and in case of severe liver disease the possibility of double and triple coinfection should be kept in consideration
Expression of EBV Encoded viral RNA 1, 2 and anti-inflammatory Cytokine (interleukin-10) in FFPE lymphoma specimens: a preliminary study for diagnostic implication in Pakistan
<p>Abstract</p> <p>Background</p> <p>Epstein Barr Virus (EBV) plays a significant role as a cofactor in the process of tumorigenesis and has consistently been associated with a variety of malignancies. EBV encoded RNAs (EBER1 and EBER2) are the most abundant viral transcripts in latently EBV-infected cells and their role in viral infection is still unclear. Formalin Fixed Paraffin Embedded (FFPE) tissues of surgically removed carcinoma biopsies are widely available form but have never been exploited for expressional studies previously in Pakistan. Immunohistochemistry (IHC) and <it>in situ </it>hybridization (ISH) in FFPE biopsy tissues remains the gold standard for proving EBV relationship in a histopathological lesion but their reagents associated limitations confines their reliability in some applications. Recently introduced targeted drug delivery systems induce viral lytic gene expression and therefore require more sensitive method to quantify viral as well as cellular gene expression.</p> <p>Methods</p> <p>Eight (8) lymphoma samples were screened to detect the EBV genome. Qualitative and quantitative expression of EBV Encoded RNAs (EBER1, EBER2) and anti-inflammatory cytokine (interleukin-10) in FFPE EBV positive lymphoma tissue samples were then analysed by using Reverse transcriptase Polymerase Chain Reaction (RT-PCR) and Real Time Polymerase Chain Reaction (qRT-PCR), respectively.</p> <p>Results</p> <p>In this study we have successfully quantified elevated expressional levels of both cellular and viral transcripts, namely EBER1, EBER2 and anti-inflammatory cytokine (IL-10) in the FFPE Burkitt's lymphoma (BL) specimens of Pakistani origin.</p> <p>Conclusions</p> <p>These results indicate that FFPE samples may retain viral as well as cellular RNA expression information at detectable level. To our knowledge, this is first study which represents elevated expressional levels of EBER1, EBER2 and IL-10 in FFPE tissue samples of Burkitt's lymphoma in Pakistan. These observations will potentially improve current lacunas in clinical as well as diagnostic practices in Pakistan and can be further exploited to develop new strategies for studying cellular and/or viral gene expression.</p
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