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1.
SEPT12 is a testis‐specific gene involved in the terminal differentiation of male germ cells. SEPT12 protein is required for sperm head‐tail formation and acts as a fundamental constituent of sperm tail annulus. In this study, we screened genetic variations in exons 5, 6, 7 of the SEPT12 and assessed the annulus status in teratozoospermic, globozoospermic, and patients with immotile short tail sperm. DNA sequencing was performed for 90 teratozoospermic and 30 normozoospermic individuals. Immunocytochemistry, transmission electron microscopy and western blotting were conducted to evaluate annulus status and the expression level of SEPT12 in patients with a distinct exonic variation (c.474G>A), respectively. Five polymorphisms identified within the desired regions of the SEPT12, among them c.474G>A had the potential to induce aberrant splicing results in the expression of a truncated protein. The annulus was detected in most of the spermatozoa from teratozoospermic and normozoospermic men with c.474G>A. In contrast, in the patient with short tail sperm defect carrying c.474G>A, 99% of spermatozoa were devoid of the annulus. Based on our findings there would be no association between exons 5, 6, 7 polymorphisms of the SEPT12 gene and the occurrence of mentioned disease but c.474G>A would be a predisposing factor in male infertility.  相似文献   
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Biochemical Genetics - Several studies have noted that vitamin D receptor (VDR) gene polymorphisms are involved in the susceptibility to Coronary artery disease (CAD). Nonetheless, the results have...  相似文献   
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Hydrobiologia - Many populations of Caspian Sea trout (Salmo caspius)—a nationally endangered species in Iran—have been extirpated or depleted due to anthropogenic impacts. The Lar...  相似文献   
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The current study aimed at evaluating the possibility of native Bacillus pumilus species to control Fusarium wilt in tomato and examine its effect on plant growth. Biocontrol traits of B. pumilus strains, biofilm assay, root colonisation and in vivo studies under pot conditions were determined. Strain ToIrMA-KC806242 formed biofilm efficiently and could colonise and survive on tomato rhizosphere (3.1 × 104 CFU/g of root). The amount of auxin production was recorded 29.7 μg/ml at the 96th hour of incubation. Siderophore production was determined positive, while ToIrMA was not able to solubilise phosphate compounds or produce cyanide hydrogen. Statistical analysis of data revealed that the increase in root and shoot length was recorded 60 and 84%, respectively, over control. In addition, about 73% reduction in disease incidence was determined in vivo experiments. In conclusion, this study suggests B. pumilus ToIrMA strain as a possible biocontrol agent in the field experiments.  相似文献   
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Understanding the penetration mechanisms of carbon nanotube (CNTs)-encapsulated drugs through the phospholipid bilayer cell membrane is an important issue for the development of intracellular drug delivery systems. In the present work, steered molecular dynamics (SMD) simulation was used to explore the possibility of penetration of a polar drug, paclitaxel (PTX), encapsulated inside the CNT, through a dipalmitoylphosphatidylcholine bilayer membrane. The interactions between PTX and CNT and between PTX and the confined water molecules inside the CNT had a significant effect on the penetration process of PTX. The results reveal that the presence of a PTX molecule increases the magnitude of the pulling force. The effect of pulling velocity on the penetration mechanism was also investigated by a series of SMD simulations, and it is shown that the pulling velocity had a significant effect on pulling force and the interaction between lipid bilayer and drug molecule.  相似文献   
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Studying the effect of a magnetic field on oligonucleotide DNA can provide a novel DNA manipulation technique for potential application in bioengineering and medicine. In this work, the optical and electrochemical response of a 100 bases oligonucleotides DNA, cytosine-guanine (CG100), is investigated via exposure to different magnetic fields (250, 500, 750, and 1000 mT). As a result of the optical response of CG100 to the magnetic field, the ultra-violet-visible spectrum indicated a slight variation in the band gap of CG100 of about 0.3 eV. Raman spectroscopy showed a significant deviation in hydrogen and phosphate bonds’ vibration after exposure to the magnetic field. Oligonucleotide DNA mobility was investigated in the external electric field using the gel electrophoresis technique, which revealed a small decrease in the migration of CG100 after exposure to the magnetic field.  相似文献   
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Gastric cancer is the second cause of cancer-related mortality and the fourth most common cancers worldwide. Owing to the immune modulatory effect of vitamin D in the body, the role of vitamin D receptor gene in vitamin D regulation receives a great deal of research interest. The aim of the current study was to highlight the association between two variants of TaqI and FokI in the vitamin D receptor gene and gastric cancer predisposition in a sample of South Khorasan population. The present investigation consisted of 69 patients affected with gastric cancer and 100 healthy individuals. The genomic DNA was extracted by salting out the protocol from peripheral venous blood. Genotyping of TaqI and FokI variants were performed by PCR-RFLP method. Our findings manifested that TC genotype of TaqI polymorphism was statistically significant between the case and the control groups (p = 0.002). Moreover, the frequency of TC + CC genotypes was statistically significant between the two groups (p = 0.009). Furthermore, we could not find any meaningful association between FokI variant and the participant groups. The present results declared that, in our population, TC genotype of TaqI polymorphism has an association with gastric cancer susceptibility. In addition, more investigation with greater sample sizes is needed to confirm our results.  相似文献   
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