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Parkinson??s disease (PD) is a progressive degenerative disorder of the central nervous system. Levodopa (L-dopa), dopamine precursor is the most effective therapeutic drug for PD patients. Levodopa (LDP) and its three metabolites in rat plasma were determined using high performance liquid chromatography coupled with tandem mass spectrometry (LC?CMS/MS). Method validation was conducted in terms of linearity, accuracy, precision, recovery, specificity, limit of detection, limit of quantification and stability. Correlation coefficients (r 2) were above 0.9965. The intra-day accuracy values at LLOQ (low limit of quantification), LQC (low quality control), MQC (medium quality control) and HQC (high quality control) levels were 85.7?C103.3, 96.5?C105.1, 90.7?C100.1 and 94.2?C101.3?%, respectively. The inter-day accuracy values at LLOQ, LQC, MQC and HQC levels were 77.6?C112.0, 91.1?C109.3, 84.3?C101.0 and 88.2?C103.9?%, respectively. The coefficient of variation (RSD) values of both intra- and inter-day results were within 6.7 and 8.5?%, respectively. The recoveries (mean?±?%SD) for LLOQ, LQC, MQC and HQC were 82.7?±?3.7?C113?±?2.8?%, 86.6?±?5.7?C110.3±3.4?%, 90.9?±?3.6?C106?±?6.5 and 89.7?±?4.5?C97.4?±?6.7?%, respectively. The coefficient of variation (RSD) values of both intra- and inter-day results were within 6.7 and 8.5?%, respectively. The validated LC?CMS/MS method was applied successfully to the measurement of LDP and its metabolites in the rat plasma samples.  相似文献   
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Adenosine deaminases (ADA) are key enzymes that deaminate adenosine (A) or deoxyadenosine (dA) and produce inosine or deoxyinosine (dI), respectively. While ADA only deaminates free dA, reactive nitrogen species (RNS) or reactive oxygen species (ROS) deaminate adenine base on the DNA and leave dI, which is a pre-mutagenic lesion. Therefore, dI adduct in the genomic DNA has been considered a biomarker of DNA damage caused by RNS or by ROS.  相似文献   
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ABSTRACT: BACKGROUND: Although soybeans have the ability to attenuate insulin resistance, it is insufficient to alleviate type 2 diabetic symptoms and different types of fermented soybeans may have even better anti-diabetic effects. Meju, unsalted fermented soybeans exhibited better insulin sensitizing and insulinotropic actions than unfermented cooked soybeans (CSB). We investigated whether meju fermented in the traditional (TMS) manner for 60 days and meju fermented in the standardized (MMS) method inoculating Bacillus subtilis and Aspergillus oryzae for 6 days modulated insulin resistance, insulin secretion, and pancreatic beta-cell growth and survival in 90% pancreatectomized (Px) diabetic rats, a moderate and non-obese type 2 diabetic animal model. METHODS: Diabetic rats were divided into 3 groups: 1) TMS (n = 20), 2) MMS (n = 20) or 3) casein (control; n = 20). Rats were provided with a high fat diet (40 energy % fat) containing assigned 10% meju for 8 weeks. At the end of experiment insulin resistance and insulin secretion capacity were measured by euglycemic hyperinsulinemic clamp and by hyperglycemic clamp, respectively. Additionally, beta-cell mass and islet morphohometry were determined by immunohistochemistry and insulin signaling in the liver was measured by western blot. RESULTS: TMS and MMS increased isoflavonoid aglycones much more than CSB. CSB and TMS/MMS improved glucose tolerance in diabetic rats but the mechanism was different between treatments (P < 0.05). CSB enhanced peripheral insulin sensitivity including hepatic insulin sensitivity better than the control but TMS and MMS enhanced only hepatic insulin sensitivity through activating insulin signaling in diabetic rats (P < 0.05). However, TMS and MMS, but not CSB, potentiated glucose-stimulated insulin secretion and beta-cell mass (P <0.05). MMS had better insulinotropic actions than the control (P < 0.05). CONCLUSIONS: The anti-diabetic action of MMS, especially when fermented with Bacillus subtilis and Aspergillus oryzae, was superior to CSB by increasing isoflavonoid aglycones and small peptides with regard to type 2 diabetic rats.  相似文献   
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This study investigated the hypoglycemic, hypolipidemic, and antioxidant effects of dietary quercetin in an animal model of type 2 diabetes mellitus. Four-week-old C57BL/KsJ-db/db mice (n = 18) were offered an AIN-93G diet or a diet containing quercetin at 0.04% (low quercetin, LQE) or 0.08% of the diet (high quercetin, HQE) for 6 weeks after 1 week of adaptation. Plasma glucose, insulin, adiponectin, and lipid profiles, and lipid peroxidation of the liver were determined. Plasma glucose levels were significantly lower in the LQE group than in the control group, and those in the HQE group were even further reduced compared with the LQE group. The homeostasis model assessment for insulin resistance (HOMA-IR) showed lower values for LQE and HQE than for the control group without significant influence on insulin levels. High quercetin increased plasma adiponectin compared with the control group. Plasma triglycerides in the LQE and HQE groups were lower than those in the control group. Supplementation with high quercetin decreased plasma total cholesterol and increased HDL-cholesterol compared with the control group. Consumption of low and high quercetin reduced thiobarbituric acid reactive substances (TBARS) levels and elevated activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the liver. Thus, quercetin could be effective in improving hyperglycemia, dyslipidemia, and antioxidant status in type 2 diabetes.  相似文献   
96.
Dysembryoplastic neuroepithelial tumors (DNETs) arise mostly in the supratentorial cerebral cortex. A very rare case of intraventricular DNET with diffuse ependymal involvement, which causes spinal drop metastasis, is presented.  相似文献   
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