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31.
To investigate the involvement of the CYP17, SRD5A2, CYP1B1, and CYP2D6 variants with prostate cancer, a case-control study of 100 patients and an equal number of age-matched control men was conducted. There appears to be a nonsignificant increase with risk of prostate cancer for individuals carrying one copy of the CYP17 A2 allele (OR, 1.80; 95% CI, 0.99-3.29, P=0.05). The risk was increased in individuals having two A2 alleles (OR; 2.81, 95% CI, 1.06-7.40, P=0.03). Compared with men having the VV genotype of SRD5A2 gene, there was no significant association between the VL genotype and the risk of prostate cancer (OR; 0.54, 95% CI; 0.29-1.03, P=0.06). There was no difference in the occurrence of the genotype LL between controls and prostate cancer patients (OR; 0.90, 95% CI; 0.43-1.89, P=0.79). There was a nonsignificant increased risk of prostate cancer for individuals carrying the CYP1B1Leu/Val genotype (OR, 1.70, 95% CI, 0.91-3.17, P =0.09), which was increased in those having the Val/Val allele (OR, 3.38; 95% CI, 1.13-10.07, P=0.02). Relative to men homozygous for the wild-type allele in CYP2D6 gene, those heterozygous for the B allele had an odds ratio of 1.78 (95% CI, 0.76-4.17, P=0.18) for patients, and for homozygous individuals, it was 1.95 (0.55-6.93, P=0.30). These observations have suggested that the CYP17 A2/A2, CYP1B1 Val/Val, and CYP2D6 genotypes may be associated with an altered risk of prostate cancer, while the CYP2D6 and SRD5A2 V89L polymorphism have no association with its risk in the North Indian population.  相似文献   
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A series of iminopyridine ligands; cyclopropylpyridin-2-ylmethyleneamine (A), cyclopentylpyridin-2-ylmethyleneamine (B), cyclohexylpyridin-2-ylmethyleneamine (C), and cycloheptylpyridin-2-ylmethyleneamine, (D) and their copper(I) complexes, [Cu(L)2]+ (1a-1d) and [Cu(L)(PPh3)2]+ (2a-2d) have been synthesized and characterized by CHN analyses, 1H NMR and IR and UV-Vis spectroscopy. Structures of 1a, 1b, 1c and 2a were determined by X-ray crystallography. The coordination polyhedron about the CuI center in the complexes is best described as a distorted tetrahedron. The dihedral angles between the least-squares planes of the chelate ligands show considerable variation from 86.1° in 1a to 68.3° in 1b, indicating the importance of packing forces in the crystalline environment. The UV-Vis spectra of the complexes are characterized by first metal to ligand charge transfer bands increasing in wavelength with increasing size of the ring substituents in the ligands, except for the cyclopropyl compounds (1a and 2a), in good agreement with the variation of the dihedral angles between the ligand planes. Cyclic voltammetry of the complexes indicates a quasireversible redox behavior for the complexes. The bulkier ligands (PPh3) inhibit the geometric distortion within the oxidized form and the redox potentials of complexes 2a-2d are shifted to more positive values, therefore.  相似文献   
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This study was designed to investigate the possible effects of 24-Epibrassinolide (BR), arbuscular mycorrhizal (AM) fungus, Glomus mosseae, singularly and collectively under salt stress in wheat (Triticum aestivum L.) plants. After foliar spraying of mycorrhizal and non-mycorrhizal plants by 5 µM epibrassinolide (24-Epi), they were treated with 0 and 150 mM NaCl for 2 weeks and then harvested. The results showed interactions of G. mosseae and 24-Epi could alleviate the adverse effects of salinity by improving relative water content (RWC) of leaves (62%), relative growth rate (40.74%), shoot fresh weights (39.83%) and shoot phosphorous content (63.93%), stimulating leaf enzymatic antioxidant activities including catalase (2.24 fold) and ascorbate peroxidase (2.18 fold) as well as malondialdehyde (36.17%) and H2O2 concentrations (49.74%) as compared to those of NaCl treatments. Moreover, mycorrhizal dependency of root dry weight (2%) and phosphorus concentration (0.4%) increased with AM infection and 24-Epi application under saline condition. Leaf RWC, also, negatively correlated with membrane electrolyte leakage. Furthermore, the greatest mitigating effects were observed in mycorrhizal plants subjected to NaCl and 24-Epi. This study indicated that 24-Epi application and AM fungi may synergistically mitigate harmful impacts of salinity in wheat plants.  相似文献   
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Nickel oxide nanoparticles (NiO‐NPs) are progressively used for an immense number of new applications in modern industries sectors. Nevertheless, the toxic impact of NiO‐NPs has not been clearly elucidated on human melanoma cell lines at the cellular and molecular level. Hence, this study was designed to examine the in vitro cytotoxicity potentials of NiO‐NPs on malignant cutaneous melanoma (MCM) mitochondria. Results revealed that NiO‐NPs significantly increased reactive oxygen species level, lipid peroxidation, and mitochondrial membrane potential and decreased succinate dehydrogenase activity, glutathione level, and ATP content on skin mitochondria isolated from the mouse model of melanoma compared with the non‐cancerous mouse skin mitochondria. Our results revealed that NiO‐NPs induced lysosomal membrane labialization on mentioned mitochondria. The current study showed that NiO‐NPs could significantly induce selective cytotoxicity on MCM mitochondria. Therefore, this compound may be considered as a promising candidate for further in vivo and clinical studies to reach a new anti‐MCM drug.  相似文献   
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The role of somites and notochords in neuroectoderm differentiation from the embryonic ectoderm and its subsequent patterning into regional compartments along rostro-caudal and dorso-ventral axes, especially in humans, remains elusive. Here, we demonstrate the co-culture effect of somites and notochords isolated from chicken embryos on the neuronal differentiation and regional identity of an adherent culture of human embryonic stem cells (hESCs). Notochord increased the efficiency and speed of neuronal induction, whereas somites had a weak neuronal inducing effect on hESCs. However, a synergistic effect was not observed when notochords and somites were used together. Moreover, in somite and notochord co-culture groups, hESCs-derived neuronal cells expressed HOXB4, OTX2, IRX3 and PAX6, indicative of dorsal hindbrain and ventral anterior identities, respectively. Our results reveal the influence of embryonic notochord and somite co-culture in providing neuronal induction as well as rostro-caudal and dorso-ventral regional identity of hESCs-derived neuronal cells. This study provides a model through which in vivo neuronal induction events may be imitated.  相似文献   
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Effect of penconazole (PEN) on the expression level of two genes in the biosynthesis pathway of monoterpenes, isopiperitenone reductase (iPR) and pulegone reductase (PR), and essential oil (EO) compounds were studied at flowering stage of Mentha pulegium L. under drought stress. Plants were grown with different levels of field capacity (100 and 50 %) with or without PEN (15 mg l?1). Results showed that drought stress decreased the growth and productivity parameters. PEN treatment to drought-stressed plants decreased the negative effects of drought stress on these parameters. The EO yield increased by about 1.6 times under drought stress, and the highest amount of EO was obtained in drought-stressed with PEN. Drought stress increased pulegone and decreased menthone percentage, and the highest pulegone percentage (78.2 % of total constituents) was obtained in drought-stressed with PEN treatment. Semi-quantitative RT-PCR showed drought stress increased the expression level of iPR and PR genes. PEN treatment promoted the impact of drought stress on iPR gene expression and repressed PR gene expression. Our results suggest that PEN may be a useful tool for the regulation of monoterpene metabolism in M. pulegium under stress condition.  相似文献   
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