RESUMO
Background: Recurrent miscarriage is one of the most prevalent reproductive diseases. This phenomenon has several reasons, including maternal, hormonal, immunological, and parental genetic factors. Idiopathic recurrent miscarriage (IRM), with no distinctive etiology, involves about half of the recurrent miscarriage cases. Some mutations in mitochondrial DNA can lead to miscarriage. Mitochondrial tRNA (mt-tRNA) mutations cause nearly half of the mitochondrial disorders. Objective: To identify mt- tRNACys&Tyr gene mutations in Iranian women with IRM. Materials and Methods: In this case-control study, 100 Iranian women with IRM and 100 women as control without any history of miscarriage were investigated by polymerase chain reaction-single strand conformation polymorphism technique followed by gene sequencing. Bioinformatics analysis were done using human mitochondrial genome database, molecular evolutionary genetics analysis, mammalian mitochondrial-tRNA, etc. Results: Results showed 4 mt-tRNA mutations including 1 cysteine mt-tRNA mutation (5824C>T) and 3 tyrosine mt-tRNA mutations (5868T>A, 5849C>T, and 5836T>C) in our cases. Conclusion: Amongst the 4 mutations found, one was novel that is still not reported. Our bioinformatics analysis revealed that these mutations can be pathogenic. They occurred in tRNA-conserved regions and their secondary structure was changed, which can result in mitochondrial dysfunction. Mutations of these genes may help in the assessment of IRM. Further study of all 22 mt-tRNAs possible mutations is recommended to describe their etiologic role in IRM.
RESUMO
BACKGROUND: Infertility is a common problem in testicular cancer. Affected men often decide to undergo sperm banking before chemo/radiotherapy. The cumulative effects of therapy can considerably reduce fertility. OBJECTIVE: Testicular cancers impair fertilizing ability, even before diagnosis. This study tries to verify individual traits and semen quality in patients with testicular cancer. MATERIALS AND METHODS: This observational study analyzed 190 semen of patients with testicular cancer (16 to 47 yr old) referred to the sub-fertility laboratory at the St. Mary hospital for semen banking prior to treatment carcinoma. Several aspects of their semen analyses were examined. The cases were divided into four different categories: seminoma, teratoma, mixed germ cell tumors and others. RESULTS: The results showed that 23 cases were azoospermic, and 13 of the patients who were not azoospermic, their sperm of "normal" morphology were too few to count. Among patients that could produce spermatozoa, 59.4% had a sperm concentration of < 20 × 10 6 /ml. The mean of "motility excellent" and "sluggish" taken together in all the cases was 47.2%. More than 92% of the patients had an abnormal morphology. The morphology of sperm is the most sensitive semen parameter that is affected by testicular carcinoma. CONCLUSION: Abnormal spermatogenesis is seen in most patients with testicular cancer before treatment with radiation, chemotherapy, or surgery. The causes of poor semen quality in cancer patients are not well-understood, but the patients with impaired spermatogenesis should have precise examination to find out the correct diagnosis of problem and preserve the fertility before any treatment.
