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BACKGROUND: The ability of tumour suppressor protein p53 (P53) to regulate cell cycle processes can be modulated by hepatitis B virus (HBV). While preliminary evidences indicates the involvement of protein-x of HBV (HBx) in altering p53 DNA binding, no further data have been accumulated for the significance of serum p53 in chronic hepatitis B virus infected patients. METHODS: 72 non-cirrhotic and 19 cirrhotic patients infected by HBV were enrolled for the analysis in this study. Enzyme linked immunosorbent assay (ELISA) was performed to study the concentrations of serum p53 protein. The tertiary structures of HBx and P53 were docked by Z-dock and Hex servers for in-silico protein-protein interaction analysis. RESULTS: There was a significant association between the serum p53 and cirrhosis (OR=1.81 95% CI: 1.017-3.2, P=0.044). Cirrhotic patients had higher level of serum p53 compare with chronic infection of HBV (1.98±1.22 vs. 1.29±0.72 U/ml, P=0.05). No evidence of correlation was seen between the different variables such as age, gender, log viral load, serum alkaline phosphatase (ALP) and alanine aminotransferase (ALT) with serum p53. Tertiary model shows that the amino acid residues from Arg110 to Lys132 of the N-terminal of P53 which is critical for ubiquitination, are bonded to a region in N- terminal of HBx amino acid residues from Arg19 to Ser33. CONCLUSION: There is an increase in serum p53 in HBV-related cirrhosis patients. In this case, HBx might be responsible for such higher concentration of p53 through HBx-p53 protein-protein interaction, as is shown by molecular modeling approach.
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The development of the liver disease in chronic hepatitis B with common viral variants can be determined through the interaction between the virus and the host immune response. B cells constitute half of the intrahepatic lymphocyte population with an impact on fibrosis. A proliferation-inducing ligand (APRIL) has been shown to have a co-stimulatory activity on B cells. For this study HBV DNA was amplified and then sequenced to show the presence of the basal core promoter (BCP) mutations in the serum from 57 patients with chronic hepatitis B. The range of IgD-positive B cells was detected by immunohistochemistry in liver biopsies; and patients serum was assayed for APRIL levels by enzyme immunoassay. Twenty-seven patients (47.4%) harbored the A1762T-G1764A BCP mutations. Coefficients of logistic regression showed that the effect of increasing IgD-positive B cells in rising odds of the liver disease is the same in the patients with BCP mutation A1762T-G1764A and in the patients without mutation, nevertheless the effect of APRIL is not similar in these two groups of patients. Logistic regression in patients with BCP A1762T-G1764A mutations demonstrated that increasing one score of APRIL decreased the odds of fibrosis stage about 8%. These results suggest that in infection with viral variants of hepatitis B virus, the population of IgD-positive B cells may play a decisive role in later stages of the liver disease which is reduced by APRIL in chronic hepatitis patients with BCP mutations.
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Linfocitos B/inmunología , Virus de la Hepatitis B/genética , Hepatitis B Crónica/inmunología , Cirrosis Hepática/inmunología , Mutación , Regiones Promotoras Genéticas , Adulto , Biopsia , ADN Viral/genética , Ensayo de Inmunoadsorción Enzimática , Femenino , Genoma Viral , Hepatitis B/virología , Antígenos de Superficie de la Hepatitis B/análisis , Hepatitis B Crónica/virología , Humanos , Inmunohistoquímica , Hígado/patología , Hígado/virología , Cirrosis Hepática/virología , Modelos Logísticos , Masculino , Receptores Fc/inmunología , Miembro 13 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/sangreRESUMEN
BACKGROUND: Even though many functions of protein-x from the Hepatitis B virus (HBV) have been revealed, the nature of protein-x is yet unknown. This protein is well-known for its transactivation activity through interaction with several cellular transcription factors, it is also known as an oncogene. In this work, we have presented computational approaches to design a model to show the structure of protein-x and its respective binding sites associated with the CCAAT/enhancer-binding protein α (C/EBPα). C/EBPα belongs to the bZip family of transcription factors, which activates transcription of several genes through its binding sites in liver and fat cells. The C/EBPα has been shown to bind and modulate enhancer I and the enhancer II/core promoter of HBV. In this study using the bioinformatics tools we tried to present a reliable model for the protein-x interaction with C/EBPα. RESULTS: The amino acid sequence of protein-x was extracted from UniProt [UniProt:Q80IU5] and the x-ray crystal structure of the partial CCAAT-enhancer α [PDB:1NWQ] was retrieved from the Protein Data Bank (PDB). Similarity search for protein-x was carried out by psi-blast and bl2seq using NCBI [GenBank: BAC65106.1] and Local Meta-Threading-Server (LOMETS) was used as a threading server for determining the maximum tertiary structure similarities. Advanced MODELLER was implemented to design a comparative model, however, due to the lack of a suitable template, Quark was used for ab initio tertiary structure prediction.The PDB-blast search indicated a maximum of 23% sequence identity and 33% similarity with crystal structure of the porcine reproductive and respiratory syndrome virus leader protease Nsp1α [PDB:3IFU]. This meant that protein-x does not have a suitable template to predict its tertiary structure using comparative modeling tools, therefore we used QUARK as an ab initio 3D prediction approach. Docking results from the ab initio tertiary structure of protein-x and crystal structure of the C/EBPα- DNA region [PDB:1NWQ] illustrated the protein-binding site interactions. Indeed, the N-terminal part of 1NWQ has a high affinity for certain regions in protein-x (e.g. from Ala76 to Ser101 and Thr105 to Glu125). CONCLUSION: In this study, we predicted the structure of protein-x of HBV in interaction with C/EBPα. The docking results showed that protein-x has an interaction synergy with C/EBPα. However, despite previous experimental data, protein-x was found to interact with DNA. This can lead to a better understanding of the function of protein-x and may provide an opportunity to use it as a therapeutic target.
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Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Biología Computacional/métodos , Virus de la Hepatitis B/metabolismo , Transactivadores/metabolismo , Sitios de Unión , ADN/metabolismo , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Estructura Terciaria de Proteína , Transactivadores/química , Proteínas Reguladoras y Accesorias ViralesRESUMEN
OBJECTIVES: Hepatitis B virus infection causes chronic disease such as cirrhosis and hepatocellular carcinoma. The metabolomics investigations have been demonstrated to be related to pathophysiologic mechanisms in many disorders such as hepatitis B infection. The aim of this study was to investigate the saliva metabolic profile of patients with chronic hepatitis B infection and to identify underlying mechanisms as well as potential biomarkers associated with the disease. MATERIALS AND METHODS: Saliva from 16 healthy subjects and 20 patients with chronic hepatitis B virus were analyzed by nuclear magnetic resonance (NMR). Then, multivariate statistical analysis was performed to identify discriminative metabolites between two groups. RESULTS: A set of metabolites were detected, including propionic acid, putrescine, acetic acid, succinic acid, tyrosine, lactic acid, butyric acid, pyruvic acid, 4-pyridoxic acid and 4-hydroxybenzoic acid, which in combination with one another could accurately distinguish patients from healthy controls. Our results clearly demonstrated altered metabolites are involved in nine metabolic pathways. CONCLUSION: Metabolomics has the potential to be considered as a novel clinical tool for hepatitis B diagnosis while contributing to a comprehensive understanding of disease mechanisms.
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BACKGROUND: Infertile couples are faced with problems that affect their marital life. Infertility treatment is expensive and time consuming and occasionally isn't simply possible. Prediction models for infertility treatment have been proposed and prediction of treatment success is a new field in infertility treatment. Because prediction of treatment success is a new need for infertile couples, this paper reviewed previous studies for catching a general concept in applicability of the models. METHODS: This study was conducted as a systematic review at Avicenna Research Institute in 2015. Six data bases were searched based on WHO definitions and MESH key words. Papers about prediction models in infertility were evaluated. RESULTS: Eighty one papers were eligible for the study. Papers covered years after 1986 and studies were designed retrospectively and prospectively. IVF prediction models have more shares in papers. Most common predictors were age, duration of infertility, ovarian and tubal problems. CONCLUSION: Prediction model can be clinically applied if the model can be statistically evaluated and has a good validation for treatment success. To achieve better results, the physician and the couples' needs estimation for treatment success rate were based on history, the examination and clinical tests. Models must be checked for theoretical approach and appropriate validation. The privileges for applying the prediction models are the decrease in the cost and time, avoiding painful treatment of patients, assessment of treatment approach for physicians and decision making for health managers. The selection of the approach for designing and using these models is inevitable.
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Recognition mechanisms of innate immune response help to improve immunotherapeutic strategies in HBeAg-negative chronic hepatitis B (CHB). Toll-like receptor 2 (TLR2) is an important component of innate immunity. In this study, the frequency of precore mutations of the hepatitis B virus (HBV) and serum TLR2 were evaluated in CHB patients. Fifty-one patients with chronic hepatitis B, negative for HBeAg and detectable HBV DNA, were examined for the presence of mutations in pre-core region of HBV genome by direct sequencing. Serum TLR2 was measured by enzyme-linked immunosorbent assay. Interactions of truncated HBeAg and TLR2 proteins were evaluated with molecular docking software. The G1896A pre-core mutation were detected in 29 (57%) which was significantly associated with higher concentration of serum TLR2 in comparison with patients without this mutation (4.8 ± 2.9 versus 3.4 ± 2.2 ng/mL, P = 0.03). There was also a significant correlation between serum ALT and TLR-2 (r = 0.46; P = 0.01). Docking results illustrated residues within the N-terminus of truncated HBeAg and TLR2, which might facilitate the interaction of these proteins. These findings showed the dominance of G1896A pre-core mutation of HBV variants in this community which was correlated with serum TLR2. Moreover TLR2 is critical for induction of inflammatory cytokines and therefore ALT elevation.