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Aim: To determine the distribution of important mutations of the "a" determinant region in the HBV genome among patients in different clinical phases of HBV infection. Background: Variations in Hepatitis B infection not only change the outcome of the disease but also the symptoms from which the chronic HBV patients are suffering. Methods: We have meticulously selected a total of 40 chronic HBV patients from four different subclasses of chronic HBV clinical phases including immune tolerant (IT), immune active (IA), inactive carrier (IC) and hepatitis B e antigen (HBeAg)-negative (ENEG); 10 samples per each phase. Mutations of the "a" determinant region were identified using PCR-Direct sequencing method. Results: 17 amino-acid substitutions at 12 positions inside the "a" determinant were identified in all forty samples; 3 mutations in the IT group, 6 mutations in the IA phase, 3 mutations in the IC patients and 5 mutations in the ENEG phase. Different substitutions were observed in all four clinical phases. The IA phase was the most variant group with the highest number of amino-acid substitutions. Conclusion: These results did not reveal a strong pattern to distinguish different clinical phases of Chronic HBV infection, but there are some obvious differences regarding the number and position of mutations between these four clinical phases. [ABSTRACT FROM AUTHOR]

Colorectal cancer is the third-most-prevalent form of cancer in the world. Several studies report that prostaglandins are mediators of carcinogenesis. Cyclooxygenase, also known as prostaglandin endoperoxidase H synthase, is a pro-inflammatory enzyme that intercedes in the formation of eicosanoids from arachidonic acid. Polymorphisms in the COX-2 gene have been associated with increased risk of different tumors, including colorectal. Genetic variations in COX-2 may affect enzyme activity or expression, thereby altering the production of prostaglandins and potentially modulating an individual's inflammatory response and risk of colorectal cancer. A functional polymorphism in the COX-2 promoter region (-765G>C), located at a putative stimulatory protein-1 (SP1) binding site, suggests the involvement of a complex array of factors regulating its expression. This study was designed to evaluate the status of -765G>C polymorphism (rs20417) and risk of sporadic colorectal cancer in an Iranian population. [ABSTRACT FROM AUTHOR]

Background: Tumor necrosis factor-alpha (TNF-αl), a multifunctional proinflammatory cytokine, plays an essential role in the host immune response to hepatitis B virus (HBV). The aim of this study was to examine the relationship between single-nucleotide polymorphism (SNP) in the TNF- 308 gene locus promoter and the susceptibility to chronic HBV infection. Materials and Methods: In this case-control study, genomic DNA was extracted from peripheral blood samples of 119 chronically HBV infected patients referred to Tehran Taleghani hospital and 111 healthy controls using the phenol-chloroform method. Afterwards, genotyping was performed by the ARMS-PCR method. Data were analyzed using the Chi-square test. Results: The frequencies of TNF-α genotypes (GG and GA) 308 on locus were 84.9%, 15.1% and 80.2%, 19.8% in the case and control groups, respectively. No AA genotype was seen in both groups. Moreover, no significant difference was found between the case and control groups. Conclusion: The genetic capacity for cytokine production in individuals has a major effect on their immune system response. Several SNPs have been identified in the human TNF-α gene promoter; the polymorphism at 308 locus, which involves substituting guanine (G) for adenine (A), has been linked to an increased susceptibility to several chronic inflammatory diseases. However, the results of this study indicate that there is no relation between the TNF-α-308 locus SNP and susceptibility to chronic HBV infection in Iranian population. [ABSTRACT FROM AUTHOR]

The aim of the present study was to isolate and characterize the cellulose-degrading bacteria from the gut of the local termite, Microcerotermes diversus (Silvestri), inhabiting the Khuzestan province of Iran. The microorganisms capable of growing in the liquid medium containing cellulose as the only source of carbon were isolated and their cellulolytic activity on CMC-containing media was confirmed by the congo red clearing zone assay. The isolates were identified based on biochemical characteristics and the phylogenetic analysis of 16S rRNA gene fragments. The results of the present study show that three cellulose-degrading bacteria isolated from local termite guts belonged to the genera Acinetobacter, Pseudomonas and Staphylococcus and four cellulose-degrading bacteria belonged to Enterobacteriaceae and Bacillaceae families. Several isolates recovered from separate termite Microcerotermes diversus samples closely clustered in phylogenetic trees indicating high similarity and the abundance of particular cellulolytic strains. Bacillus B5B and Acinetobacter L9B hydrolyzed cellulose faster than the other isolates (with CMCase activity of 1.47 and 1.22 U/mL, respectively). The stability of CMCase produced by Bacillus B5B over a broad range of pH and high temperature indicated that the enzyme may be of great commercial value. [ABSTRACT FROM AUTHOR]

Aim: Since data about prevalence of JC virus in Iranian population is scarce, this study was designed to evaluate the prevalence of JC virus in healthy individuals who had attended Fajr hospital and Farjam clinical laboratory in Tehran, Iran. Background: JC virus is the causative agent of progressive multifocal encephalopathy (PML) in individuals with suppressed immune system. There are some evidences that this virus is responsible for some forms of cancers for example colorectal and gastric cancers in humans. Patients and methods: Urine samples from 133 healthy individuals older than 18 years old were collected and after extraction of viral DNA, PCR was performed to determine the presence of virus. Results of the test and demographic data of subjects were entered into SPSS program and were analyzed by it. Results: 71 subjects were male and 62 individuals were female. Mean age of the population was 42.23 ± 13.47. From the total number of 133 subjects, 51 (38.3%) individuals were positive for the presence of JC virus. Gender had statistically significant relationship with JC virus presence (p= 0.042). Age was not significantly related to JC virus presence status (p= 0.3). Conclusion: Obtained rate of JC prevalence in this study is similar to the results of studies in India and Philippine. Because of this virus's role in AIDS and the role of this virus in gastrointestinal cancers have been revealed in recent years, the more extended studies on the prevalence of this virus in different populations in Iran is necessary. [ABSTRACT FROM AUTHOR]

Background: A number of methods for detecting diversity in Entamoeba have been described over the years. In the present study the genetic polymorphism of noncoding locus A-L was analyzed using PCR and sequencing in order to clarify the genotypic differences among E. dispar isolates. Methods: A total of 28 E. dispar from patients with gastrointestinal symptoms were determined and the genomic DNA was extracted directly from stool. For genotype analysis; Locus A-L was amplified by PCR and PCR products were sequenced .The sequences obtained were edited manually and aligned using Gene Runner software. Results: With sequencing of PCR products a reliable genetic diversity in size, number and position of the repeat units were observed among the Iranian E. dispar isolates in locus A-L gene. Sequences showed variation in length from 448bp to 507bp and seven distinct types were identified. Conclusion: The genetic diversity of loci like A-L shows them to be suitable for epidemiological studies such as the characterization of the routes of transmission of these parasites in Iran. [ABSTRACT FROM AUTHOR]

Aim: This study investigated the prevalence of sapovirus infections in patient with acute gastroenteritis in Tehran, Iran. Background: Sapovirus, a member of the family Caliciviridae is one of the major causative agents of viral gastroenteritis affecting both children and adult individuals. There isn't enough data about prevalence and genotypes of sapovirus infection in Tehran, the capital city of Iran. Patients and methods: A total of 42 fecal samples were collected from patients with acute gastroenteritis from May to July 2009. RT nested- PCR was performed for screening. To genotype the sapovirus isolates, some positive samples were subjected to phylogenetic analysis by sequencing of fragments of viral capsid gene region. Results: Sapovirus was detected in 5 of 42 stool specimens from patients with acute gastroenteritis. Sapovirus detected in this study was clustered into only one distinct genogroup I/2. Sapovirus GI/2 was predominant. Conclusion: Our results show that among the studied viruses responsible for this disease, sapovirus was a major viral isolate virus. [ABSTRACT FROM AUTHOR]

Background & Aims: A number of theories have been put forward to clarify the etiology of colorectal cancer (CRC), such as genetic alterations and cytokine production. A combination of inflammatory cytokines has an important role in cancer development. The aim of our study was to screen for alterations located in promoter and exons of IL-16 gene sequence, to determine the distribution of genotypes in individuals with CRC and healthy controls in a sample of Iranian population. Methods: The case group consisted of 260 individuals with colorectal cancer and the control group included 405 healthy individuals. Three IL-16 gene polymorphisms (rs4072111, rs11556218, rs4778889) were genotyped using PCR-RFLP method. RFLP results were confirmed by direct sequencing. Results: A significant association between rs11556218 SNP in the IL-16 gene and the risk of CRC was found. The TG genotype of rs11556218 T/G polymorphism showed significant association with a 1.75 fold increased risk of CRC (P=0.005; adjusted OR: 1.759; 95% CI: 1.191- 2.598). In addition a significant association between CC genotype of rs4778889 T/C polymorphism and decreased risk of CRC in male subjects (P=0.045; adjusted OR: 0.192; 95% CI: 0.038-0.967) was determined. Conclusion: This study is the first report of IL-16 gene polymorphisms among CRC patients from Iran. Our results suggest an influence of rs11556218 T>G and rs4778889 T/C polymorphisms on the altered risk of CRC. [ABSTRACT FROM AUTHOR]

Background: Cryptosporidium is a worldwide protozoan parasite and one of the most common causes of infection and diarrhea in humans and cattle. The aim of the present study was determination of subtypes of Cryptosporidium among children with diarrhea in Tehran by sequence analysis of the highly polymorphic 60-kDa glycoprotein (GP60) gene. Methods: Fecal samples were collected from 794 diarrheic children. Initial identification of Cryptosporidium was carried out on stool samples by Ziehl-Neelsen acid-fast staining method. DNA was extracted from positive microscopically samples and Cryptosporidium genotypes and subtypes were determined, accordingly. Results: Out of 794 collected samples, 19 (2.40 %) were positive for Cryptosporidium oocysts. Sequences analysis of GP60 gene showed that 17 (89.47 %) of the positive isolates were Cryptosporidium parvum and 2 (10.52 %) were C. hominis. All subtypes of C. parvum isolates belonged to allele families IIa (6/17) and IId (11/17). The most common allele in all 17 isolates belonged to IId A20G1a (41.18%). A22G1 (IF) subtype was detected in two C. hominis isolates of the children. Conclusion: The predominancy of C. parvum species (specially, IId A20G1a subtype) in current study underlines the importance of zoonotic Cryptosporidium transmission in Iran. [ABSTRACT FROM AUTHOR]

Background: Chronic hepatitis C infection is caused by the hepatitis C virus (HCV), and its clinical complications include liver cirrhosis, liver failure, and hepatocellular carcinoma. Transforming growth factor-β1 (TGF-β1) is an important cytokine in cell growth and differentiation, angiogenesis, extracellular matrix formation, immune response regulation, and cancer development and progression. Objectives: The aim of this study was to investigate the relationship between single nucleotide polymorphisms (SNPs) in TGF-β1 and chronic HCV infection among patients referred to the Taleghani Hospital, Tehran, Iran between 2008 and 2010. Patients and Methods: In this case-control study, samples were collected using a convenience sampling method. We genotyped 164 HCV patients and 169 healthy controls for 3 SNPs in the TGF-β1 gene (-509 promoter, codon 10, and codon 25). We determined the SNP genotypes by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. To confirm the PCR-RFLP genotyping results, 10% of the samples were re-genotyped using a direct sequencing method. Results: There were no significant differences in the allelic frequency distribution of SNPs at -509 C/T, +869 C/T, or +915 G/C between HCV patients and the healthy controls. Genotyping results for all three polymorphic sites were similar with no statistically significant differences between the groups. Conclusions: Most of the Iranian patients (over 85%), both healthy controls and HCV patients, had the GG genotype at the +915 G/C position, resulting in a high level of TGF-β1 production. Therefore, we concluded that the SNPs investigated by us cannot be considered as prognostic factors for HCV infection in our population, despite being reported as prognostic markers in other populations. Moreover, there is a possibility that most of the population is susceptible to HCV infection. [ABSTRACT FROM AUTHOR]

Saffron samples from Italy and Iran were analyzed for their content in aroma and bioactive compounds with different analytical techniques. HPLC was used for the identification and quantification of crocins, picrocrocin, safranal and flavonoids content, while the novel proton transfer reaction time-of-flight mass spectrometer was employed for the aroma compounds analysis. Italian saffron turned out to be richer in total crocins and safranal contents. Sample characterization was performed with an unsupervised statistical approach; tests involving different numbers of parameters deriving from the two analytical techniques were performed. The results achieved showed that the best samples classification was obtained by joining the information acquired from both techniques; following such an approach, a sharper separation between Iranian and Italian samples was achieved. Finally, among the variables that most contribute to the description of variability, isophorone, safranal and picrocrocin were identified to be the most significant. [ABSTRACT FROM AUTHOR]

Background: Chronic hepatitis B is one of the world's major health concern. The etiological agent of this infection is hepatitis B virus (HBV), which can evade the immune system response. Transforming growth factor beta 1 (TGF-β1) can act against HBV by suppressing the viral replication. The TGF-β1 also plays an important role in preventing liver damage in chronically HBV infected patients. Objectives: In this study, the association of TGF-β1 +915G/C and -509C/T gene polymorphisms with chronic hepatitis B was evaluated in Iranian patients. Materials and Methods: A population-based case–control study was conducted in Taleghani Hospital, Tehran. A number of 220 patients with chronic hepatitis B and the same number of healthy control subjects were designated the case and the control groups. The PCR-Restriction Fragment Length Polymorphism Method (PCR-RFLP) method was used for genotyping both polymorphisms. Ten percent of the control samples were sequenced to confirm the results. Results: No statically significant differences in genotype distribution and allele frequency were observed for both polymorphisms between healthy controls and patients with chronic hepatitis B. Conclusions: There was no association between TGF-β1 -509C/T and +915G/C polymorphisms with chronic hepatitis B and it seems that these changes don not play a significant role in increasing the risk of chronic infection in Iranian patients. [ABSTRACT FROM AUTHOR]

Background: chronic hepatitis B virus (HBV) infection is a multifactorial disease that can result in serious clinical complications. Host genetic background especially the genes that encode immunologic factors like INF-γ and its receptor (IFN-γ R) are critical in the pathogenesis of infection. Objectives: The current study aimed to investigate the association between two single nucleotide polymorphisms (SNPs) at positions -611 and -56 within the promoter region of gamma interferon receptor1 gene (IFN-γ R1) and chronic HBV infection. Materials and Methods: Genomic DNA from peripheral blood samples of 200 chronically HBV infected patients and 200 healthy blood donors, as controls, were collected and genomic DNA was extracted by phenol-chloroform method and DNA analysis genotype identification was performed by PCR-RFLP. Results: The results indicated that both SNP's frequency had a significant difference in the patient and control groups. At position -56, TT genotype was associated with patient group and P value was 0.002 and at position -611, GG genotype was further observed in control group and P value was 0.006. Conclusions: Presence of G allele at position -611 within promoter of IFN-γ R1 gene in the enrolled population for the study was related to lower risk of disease, and presence of T allele at position -56 was also related to susceptibility to chronic HBV infection. Men had higher frequency of chronic HBV infection, which might be the result of high risk behavior. [ABSTRACT FROM AUTHOR]

Background: Co-infection with hepatitis C virus (HCV) and/or human immunodeficiency virus (HIV) in patients with chronic hepatitis B virus (HBV) infection can alter the course of the disease. Objectives: In this study, we investigated the frequency of HIV and/or HCV co-infection in chronic HBV patients and related risk factors in acquiring the HCV and or HIV co-infectionit. Patients and Methods: We studied 264 chronic HBV patients who visited the Gastrointestinal and Liver Ward of the Taleghani Hospital, Tehran, Iran between 2006 and 2010. Demographic information and records of possible risky behavior were obtained. Antibodies against HBV, HCV, and HIV, levels of alanine transaminase (ALT) and aspartate transaminase (AST), and conversion from hepatitis B e antigen (HBeAg) to hepatitis B e antibody (HBeAb) were evaluated. Results: of 264 patients with chronic HBV in this study, 184 patients (70%) were men and 78 patients (30%) were women. only 1 patient (0.37%) was positive for anti-HIV antibody, whereas 12 patients (4.54%) were positive for anti-HCV antibody. none of the patients had co-infection with all 3 viruses (HBV, HIV, and HCV). Conclusions: This study demonstrated that the prevalence of HCV is higher than that of HIV in chronic HBV patients. Since HCV or HIV co-infection affects the therapeutic outcome in chronic HBV patients, testing for HIV and HCV is recommended, especially for patients with a history of risky behavior. [ABSTRACT FROM AUTHOR]