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21.
This study was performed to determine the effects of levamisole and levamisole + vitamin C against Syphacia muris naturally infection in rats and to detect its effect on the oxidative parameters in blood and tissues of host. For this purpose, natural infection was diagnosed using the cellophane tape method on the perianal region of rats. Infected rats (total 18) were divided into three groups. On the other hand six without helminth rats were used in this study as negative control group. Group 2 was given an orally levamisole HCl treatment with gastric gavage at a dose level of 20 mg/kg body weight in distilled water, every alternate day. Group 3 was given levamisole HCl via gastric gavage at a dose level of 20 mg/kg and vitamin C was given 1 g/L added to the drinking water. All the treatments continued for a period of 7 days. As a result; levamisole administered to rats at dose of 20 mg/kg orally 98.34% was found to be effective against adult S. muris in the rats. In addition to levamisole + vitamin C is effective to alleviate the oxidative damage in rats infected with S. muris.  相似文献   
22.
Sinan S  Kockar F  Arslan O 《Biochimie》2006,88(5):565-574
Human serum paraoxonase (PON1, EC 3.1.8.1.) is a high-density lipid (HDL)-associated, calcium-dependent enzyme; its physiological substrates are not known. In this study, a new purification strategy for human PON1 enzyme was developed using two-step procedures, namely ammonium sulfate precipitation and sepharose-4B-l-tyrosine-1-napthylamine hydrophobic interaction chromatography. SDS-polyacrylamide gel electrophoresis of the enzyme indicates a single band with an apparent MW of 43 kDa. Overall purification rate of our method was found 227-fold. The V(max) and K(m) of the purified enzyme were determined 227.27 EU and 4.16 mM, respectively. The in vitro effects of commonly used antibiotics, namely gentamycin sulfate and cefazolin sodium was also investigated on the purified human serum PON1 enzyme and human liver PON1 enzyme from human hepatoma cell (HepG2). Gentamycin sulfate and cefazolin sodium caused a dose- and time-dependent decrease on PON1 activity in HepG2 cells. Moreover, gentamycin sulfate and cefazolin sodium were effective inhibitors on purified human serum PON1 activity with IC(50) of 0.887 and 0.0084 values, respectively. The kinetics of interaction of gentamycin sulfate and cefazolin sodium with the purified human serum PON1 indicated a different inhibition pattern. Cefazolin sodium showed a competitive inhibition with K(i) of 0.012+/-0.00065 mM. However, Gentamycin sulfate was inhibited in non-competitive manner with K(i) of 0.026+/-0.015. In order to determine the inhibition statue of these drugs on a living system, the effects of same antibiotics on PON1 enzyme activity of mouse serum PON1 and liver PON1 were investigated in vivo. Gentamycin sulfate (3.2 mg/kg) and cefazolin sodium (106.25 mg/kg) leads to the significant decrease in mouse serum PON1 after 2, 4, 6 h and 2, 4 h drug administration, respectively. Cefazolin sodium did not exhibit any inhibition effect for the liver PON1, in vivo.  相似文献   
23.
Human sex hormone binding globulin (hSHBG) is a serum glycoprotein central to the transport and targeted delivery of sex hormones to steroid‐sensitive tissues. Several molecular mechanisms of action of hSHBG, including the function of its attached glycans remain unknown. Here, we perform a detailed site‐specific characterization of the N‐ and O‐linked glycosylation of serum‐derived hSHBG. MS‐driven glycoproteomics and glycomics combined with exoglycosidase treatment were used in a bottom‐up and top‐down manner to determine glycosylation sites, site‐specific occupancies and monosaccharide compositions, detailed glycan structures, and the higher level arrangement of glycans on intact hSHBG. It was found that serum‐derived hSHBG is N‐glycosylated at Asn351 and Asn367 with average molar occupancies of 85.1 and 95.3%, respectively. Both sites are occupied by the same six sialylated and partly core fucosylated bi‐ and triantennary N‐Glycoforms with lactosamine‐type antennas of the form (±NeuAcα6)Galβ4GlcNAc. N‐Glycoforms of Asn367 were slightly more branched and core fucosylated than Asn351 N‐glycoforms due probably to a more surface‐exposed glycosylation site. The N‐terminal Thr7 was fully occupied by the two O‐linked glycans NeuAcα3Galβ3(NeuAcα6)GalNAc (where NeuAc is N‐acetylneuraminic acid and GalNAc is N‐acetylgalactosamine) and NeuAcα3Galβ3GalNAc in a 1:6 molar ratio. Electrophoretic analysis of intact hSHBG revealed size and charge heterogeneity of the isoforms circulating in blood serum. Interestingly, the size and charge heterogeneity were shown to originate predominantly from differential Asn351 glycan occupancies and N‐glycan sialylation that may modulate the hSHBG activity. To date, this work represents the most detailed structural map of the heterogeneous hSHBG glycosylation, which is a prerequisite for investigating the functional aspects of the hSHBG glycans.  相似文献   
24.
The ectoenzyme ENPP1 (also termed membrane glycoprotein PC-1 or ENPP1/PC-1) is an inhibitor of insulin-induced activation of the insulin receptor. There is evidence from previous studies that coding variants of ENPP1/PC-1 (K121Q) are associated with type 2 diabetes (T2D) and obesity. Studies in the general Turkish population have demonstrated: unique plasma lipid characteristics, a high prevalence of cardiovascular risk factors, and an increased prevalence of obesity and T2D. We investigated, therefore, the association of ENPP1/PC-1 variants with obesity and T2D in Turkish individuals. The TaqMan allelic discrimination assay was used for genotyping the relationship of ENPP1/PC-1 variants to obesity and T2D in a genetic association study of 1,553 genotyped, randomly selected subjects from the Turkish Heart Study. The K121Q (rs1044498) variant and other previously reported variants (rs997509, rs1799774, rs1044548, rs11964389, rs7754561) were analyzed. In this cohort, the minor allele frequency (MAF) of the K121Q variant was associated with obesity in male, but not in female subjects (male, odds ratio 1.64, 95% confidence interval 1.004-2.698, P = 0.048; female, odds ratio 1.003, 95% confidence interval 0.684-1.471, P = ns). In addition, the previously reported ENPP1/PC-1 "risk haplotype" (Q (rs1044498), delT (rs1799774), and G (rs7754561) alleles) was found to be associated with obesity in male, but not in female, subjects (P = 0.035). In contrast, there was no association of either the K121Q variant or the ENPP1/PC-1 haplotype with T2D. We find evidence that variants of ENPP1/PC-1 are associated with obesity in the male Turkish population; thus, these variants may contribute to the development of the obesity in these individuals.  相似文献   
25.
We investigated the influence of 2-furan-2-yl-1H-benzimidazole regarding vitamins A, E, C, selenium (Se), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) levels on rats. 2-Furan-2-yl-1H-benzimidazole was given to rats by subcutaneous injection every other day for a total of 22 injections. At the end of the experiment, Se levels were determined by using a fluorimetric method. Serum levels of vitamins A, E, C, and malondialdehyde (MDA) were determined by high-performance liquid chromatography. Glutathione peroxidase (GSH-Px) levels of erythrocytes were spectrophotometrically determined. Our experimental results showed that vitamins A, E, C, and Se levels were found generally lower than the control groups, while serum MDA level and GSH-Px activity flexibly increased, which is dependent on injection days. The observed decreases in vitamins A, E, C, and Se levels in the blood might be causally related to the increased amount of free radicals that are generated with 2-furan-2-yl-1H-benzimidazole injection. However, further investigations are needed to clarify the significance of this observation in respect with the 2-furan-2-yl-1H-benzimidazole injection.  相似文献   
26.
It is reported that the pineal gland and its main hormone melatonin may have a role in the regulation of ghrelin synthesis in the brain. Stomach is the place where ghrelin is predominantly expressed and secreted. One aim of this study was to investigate possible effects of pinealectomy and melatonin treatment on gastric ghrelin amount. The studies on the effects of the pineal gland on leptin and ghrelin arises the question whether the pineal gland has also effects on the other energy-regulatory peptides such as peptide YY (PYY) and neuropeptide Y (NPY). Therefore, we also aimed to investigate the changes in the immunohistochemical staining of intestinal PYY and hypothalamic NPY following pinealectomy and melatonin treatment. Serum PYY levels were also investigated. Sprague-Dawley rats were divided into four groups as sham-operated (SHAM), sham-operated with melatonin treatment (SHAM-MT), pinealectomised (PNX) and melatonin-treated PNX (PNX-MT) groups. The cells immunostained for ghrelin were abundant throughout the gastric mucosa in all the groups. Neither pinealectomy nor exogenous melatonin affected significantly immunohistochemical staining of ghrelin in stomach. Pinealectomy resulted in a significant increase in immunohistochemical staining of PYY in ileum. The results of serum PYY measurement corresponded closely to the data obtained by immunohistochemical analysis of PYY in ileum, being significantly lower and higher in SHAM and PNX groups, respectively. Pinealectomy caused a decrease in NPY synthesis in ARC as understood from low immunohistochemical staining of NPY. Melatonin treatment increased NPY synthesis in SHAM rats and restored reduction in NPY synthesis caused by pinealectomy. In conclusion, the pineal gland and its main hormone melatonin can be suggested to have a role in the regulation of NPY synthesis in ARC and PYY in gastrointestinal system.  相似文献   
27.
Poly(2-hydroxyethylmethacrylate) (pHEMA) based flat sheet membrane was prepared by UV-initiated photopolymerization technique. The membrane was then grafted with -histidine. Catalase immobilization onto the membrane from aqueous solutions containing different amounts of catalase at different pH was investigated in a batch system. The maximum catalase immobilization capacity of the pHEMA–histidine membrane was 86 μg cm−2. The activity yield was decreased with the increase of the enzyme loading. It was observed that there was a significant change between Vmax value of the free catalase and Vmax value of the adsorbed catalase on the pHEMA–histidine membrane. The Km value of the immobilized enzyme was higher 1.5 times than that of the free enzyme. Optimum operational temperature was 5°C higher than that of the free enzyme and was significantly broader. It was observed that enzyme could be repeatedly adsorbed and desorbed without loss of adsorption capacity or enzyme activity.  相似文献   
28.
The opening of the Suez Canal in 1869 caused a migration generally from the Red Sea to the Mediterranean, rarely the opposite direction, and 63 lessepsian fish species penetrated into the Mediterranean by way of this canal. These species usually spread northward and most of them can establish wide populations in this area, but some of them can not be successful with respect to establishment. Thus, it is clearly seen that there are a lot of factors influencing the success of species with respect to migration, spreading and establishment. So, the lessepsian migration has been formed by the effects of these factors. Lessepsian species also have the ability to adapt to the ecological conditions of their new environment. Therefore, the influential factors, their effectiveness and the observed changes in lessepsian species due to the effects of these factors have been discussed by considering fishes in this paper.  相似文献   
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