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341.
In this case–control study, we aimed to evaluate the serum and seminal plasma levels of Selenium (Se), total antioxidant capacity (TAC), and Coenzyme Q10 (CoQ-10) and determine their relationship with sperm concentration, motility, and morphology in men with idiopathic infertility. A total of 59 subjects were enrolled in the study. Forty four patients were diagnosed with idiopathic male infertility and had abnormal sperm parameters, and 15 subjects had normal sperm parameters with proven fertility. Serum Se, semen Se, and semen TAC levels were significantly different in the fertile and infertile groups (p?<?0.01, p?<?0.001, and p?<?0.001, respectively). However, serum TAC, serum, and seminal plasma CoQ-10 levels did not differ between fertile and infertile groups. When the levels of the measured parameters were compared in serum and seminal plasma, serum levels of Se were found to be correlated positively with the semen levels in all subjects included into the study (N?=?59) (r?=?0.46, p?<?0.01). A relationship was found between neither serum and semen levels of TAC nor between serum and semen levels of CoQ-10. Correlations among measured serum and semen parameters with sperm parameters demonstrated that both the serum and semen levels of Se were correlated positively with spermatozoa concentration, motility, and morphology. Additionally, seminal plasma levels of TAC correlated positively with all these sperm parameters. On the other hand, seminal plasma levels of CoQ-10 correlated only with sperm morphology but not with concentration or motility. No relationship was observed between serum levels of TAC or serum levels of CoQ-10 and sperm parameters. In conclusion, serum and seminal plasma Se deficiency may be a prominent determinant of abnormal sperm parameters and idiopathic male infertility. Measurement of serum Se levels may help determine nutritional status and antioxidant capacity in infertile patients, which may help distinguish those patients who will benefit from supplementation therapy.  相似文献   
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Cisplatin is one of the most effective chemotherapeutic agents but injury may occur at higher doses. The aim of this study was to investigate the effect of bilberry on cisplatin induced toxic effects in rat ovary. Twenty-one female Wistar–Albino rats were utilized to form three groups: In group 1 (control group), each rat received intraperitoneal injection of 1 mL of 0.9 % NaCl saline solution during 10-days. In group 2 (cisplatin group), a single dose of 7.5 mg/kg b.w. cisplatin was given. In group 3 (cisplatin + bilberry group), a single dose of 7.5 mg/kg cisplatin and bilberry at 200 mg/kg b.w. were given for 10 days. Ovaries were surgically removed in all groups and prepared for biochemical and light microscopic investigations at the examination times. Malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) of tissue samples were measured. Histopathological damages in cisplatin administrated rats were seen such as severe edema, vascular congestion, hemorrhage and follicular degeneration in the ovary tissue. Moderate pathological alterations were observed in rats treated with bilberry plus cisplatin. Cisplatin administration significantly increased MDA production and decreased SOD, CAT, GPx and GST activities in the ovarian tissue when compared to the control group (p < 0.05). Cisplatin + bilberry administration increased antioxidant enzymes activities and reduced MDA levels. Bilberry administration seems to reduce the cisplatin induced ovarian toxicity thus it alleviates free radical damage. But it dose not protect completely rat ovary tissues.  相似文献   
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Catalase (CAT, EC 1.11.1.6) is an important enzyme in antioxidant defense system protecting animals from oxidative stress. Freshwater fish Oreochromis niloticus were exposed for 96 h to different concentrations of Ag(+), Cd(2+), Cr(6+), Cu(2+) and Zn(2+), known to cause oxidative stress, and subsequently CAT activities in liver, kidney, gill, intestine and brain were measured. In vivo, CAT was stimulated by all metals except Ag(+) in the liver and the highest increase in CAT activity (183%) resulted from 1.0 mg Cd(2+)/L exposure, whereas 0.5 mg Ag(+)/L exposure resulted in a sharp decrease (44%). In tilapia kidney, cadmium and zinc had no significant effects on CAT activity, whereas 0.1 mg Cr(6+)/L exposure caused a decrease (44%). Cadmium and zinc did not significantly affect the CAT activity in gill; however, 0.5 mg Ag(+)/L exposure caused an increase (66%) and 1.5 mg Cr(6+)/L exposure caused a decrease (97%) in CAT activity. All metals, except Cu(2+)(41% increase), caused significant decreases in CAT activity in the intestine. In brain, 1.0 mg Zn(2+)/L resulted in an increase in CAT activity (126%), while 1.5 mg Ag(+)/L exposure caused a 54% decrease. In vitro, all metals -- except Ag(+) and Cu(2+) in kidney -- significantly inhibited the CAT activity in all tissues. Results emphasized that CAT may be considered as a sensitive bioindicator of the antioxidant defense system.  相似文献   
345.
The aim of this study was to formulate silica and alginate hydrogels for immobilization of β‐glucosidase. For this purpose, enzyme kinetics in hydrogels were determined, activity of immobilized enzymes was compared with that of free enzyme, and structures of silica and alginate hydrogels were characterized in terms of surface area and pore size. The addition of polyethylene oxide improved the mechanical strength of the silica gels and 68% of the initial activity of the enzyme was preserved after immobilizing into tetraethyl orthosilicate–polyethylene oxide matrix where the relative activity in alginate beads was 87%. The immobilized β‐glucosidase was loaded into glass–silicon–glass microreactors and catalysis of 4‐nitrophenyl β‐d ‐glucopyranoside was carried out at various retention times (5, 10, and 15 min) to compare the performance of silica and alginate hydrogels as immobilization matrices. The results indicated that alginate hydrogels exhibited slightly better properties than silica, which can be utilized for biocatalysis in microfluidic platforms.  相似文献   
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Nonalcoholic fatty liver disease (NAFLD) refers to excess fat accumulation in the liver. In animal experiments and human kinetic study, we found that administration of combined metabolic activators (CMAs) promotes the oxidation of fat, attenuates the resulting oxidative stress, activates mitochondria, and eventually removes excess fat from the liver. Here, we tested the safety and efficacy of CMA in NAFLD patients in a placebo‐controlled 10‐week study. We found that CMA significantly decreased hepatic steatosis and levels of aspartate aminotransferase, alanine aminotransferase, uric acid, and creatinine, whereas found no differences on these variables in the placebo group after adjustment for weight loss. By integrating clinical data with plasma metabolomics and inflammatory proteomics as well as oral and gut metagenomic data, we revealed the underlying molecular mechanisms associated with the reduced hepatic fat and inflammation in NAFLD patients and identified the key players involved in the host–microbiome interactions. In conclusion, we showed that CMA can be used to develop a pharmacological treatment strategy in NAFLD patients.  相似文献   
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Journal of Molecular Modeling - Weak interactions of graphene surface with reactive molecular impurities are the subject of many studies since noncovalent functionalization of surface via molecular...  相似文献   
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In this study, total phenolic and flavonoid analyses of flower, leaf, and stem aqueous extracts of C. orientalis were performed. Total phenolic contents of C. orientalis extracts ranged from 12.2±0.06 to 19.0±0.07 mg GAE/g extract. Total flavonoid values range between 2.0±0.11 and 6.6±0.19 mg CE/g extract. Urease, collagenase, tyrosinase, and α-glucosidase inhibition activities were determined in vitro and the relationship between them was examined. IC50 results for all enzymes were obtained between 0.18 and 3.53 μg/mL. The aqueous extract of the plant C. orientalis showed potent cytotoxic effects against the human colon cancer cell lines DLD-1. As the extract concentration increases, cell death increases. The main fatty acid composition by GC/MS analysis is erucic acid (36.5 %). The potential binding modes of the fatty acids in the plant extract to the enzymes and possible inhibition mechanisms were determined by molecular docking calculation.  相似文献   
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