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Background and Objective: Several strains of the Echinococcus granulosus have been described based on morphological characters, intermediate host specificity and/or genetic analysis of mitochondrial and nuclear DNA. The aim of this study was to characterize different E.granulosus isolates by using sequences of mitochondrial atp6 gene.

Materials and Methods: In this study, Sixty infected liver and lungs of cattle, sheep and goats were collected from the abattoir of Varamin city-Iran during 2008. Protoscoleces were removed from each fertile cyst and DNA extracted. New and specific primers were designed for two existing genotypes (G1 and G6) of E. granulosus known to occur in Iran and applied in PCR reactions.

Results: The new primers selectively amplified the G1 and G6 genotypes of E. granulosus with specific bands of 708 and 705 bp respectively. The G1 genotype was identified in all fertile cyst samples.

Conclusion: This study showed that the new primer pairs which specifically amplify portions of the mitochondrial atp6 gene of the G1 and G6 strains of Echinococcus granulosus are proper molecular marker for investigating genetic variation in a number of isolates of E. granulosus from a range of hosts (sheep, goats, cattle) in Iran. The result of sequenced samples showed that our sequences were the same as those reported previously for these strains.

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Background and Objective: Polycystic ovary syndrome (PCOS) is the most endocrine disorder in women. This study was done to determine the effect of N-acetylcysteine with letrozole to induction of ovulation in infertile women with polycystic ovarian syndrome.

Methods: This clinical trail study was carried out on forty PCOS women with normal TSH, prolactin, hysterosalpingographies and normal spermograms. The patients in control group were received letrozole 5 mg/d for 5 days starting at day 3 of the cycle. The patients in interventional group were received letrozole 5 mg/d with NAC 1.2 g/d (group II) for 5 days starting at day 3 of the cycle. On 14^th day of cycle, transvaginal ultrasonography was performed to evaluate endometrial thickness and follicles properties. If mature follicle detected, hCG was injected and timed coitus at 12, 36 and 60 hours later advised. β-hCG level was checked on day 16 after hCG injection.

Results: The mean of endometrial thickness and follicles ovulation in hCG injection day was similar in the two groups. The pregnancy rate was 15% and 20% in control and interventional groups, respectively. This difference was not significant. The mean of follicles number was 1.13% and 1.47% in control and interventional groups, respectively. This difference was not significant.

Conclusion: NAC as an adjuvant to letrozole was not effective for ovulation induction in patients with PCOS.

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Background and Objective: Chronic infection with Hepatitis B virus (HBV) is one of the main causes of cirrhosis and hepatocellular carcinoma (HCC). The pathogenicity of the virus is determined by the multi-functional protein x (HBx). Changing the sequence of the gene encoding this protein causes the regulation of transcription and pathogenicity factors. This study was done to analyze the genetic dynamics of the HBx coding gene in a person with chronic HBV.
Methods: In this descriptive laboratory study, an infected person with chronic hepatitis B virus infection was first amplified and cloned into complete sequence of HBx encoder. Then, the reference sequences of genotypes, serotypes and different virus subtypes of the GenBank database were matched by CLC Sequence Viewer software. The comparative result was used to plot the phylogenic tree by T-rex server and population genetic analysis using DnaSP software. Natural selection at the nucleotide and protein level was performed by the Tajima's D test.
Results: No known mutation at the level of the protein was found in the chronic sequence of the HBx encoder. The results of natural selection indicated neutral mutations in the HBx gene. The phylogenetic results showed that the HBx encoding sequences in the chronic infected individual had a genetic affinity with genotype D and ayw2 subtype.
Conclusion: Neutrality polymorphism takes place in HBx coding region. Also, the phylogenetic results of the present study are consistent with the previous findings of Golestan province and Iran which have reported the prevalence of genotype D and subspecies ayw2.