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41.
The aim of the present study was to measure the changes in serum selenium, zinc, and copper in patients being treated for rheumatoid arthritis. Thirty-two patients and 52 healthy controls were included in the study. The copper level was higher and those of selenium and zinc were lower in the patients relative to controls. Treatment with methotrexate elevated the zinc levels, but not zinc and selenium. Treatments with salazopyrin, corticosteroids, chloroquine, and non-steroidal anti-inflammatory drugs did not change the levels of any of the elements studied. The decrease in zinc and selenium levels and elevation in copper levels observed in the patients probably resulted from the defense response of organism and are mediated by inflammatory-like substances.  相似文献   
42.
The genus Hypericum has received considerable interest from scientists, as it contains the variety of structurally diverse natural products which possess a wide array of biological properties. The present study was conducted to determine ontogenetic and morphogenetic variation of hypericin, chlorogenic acid and flavonoids, as rutin, hyperoside, apigenin-7-O-glucoside, quercitrin and quercetin content in Hypericum origanifolium growing in Turkey. Wild growing plants were harvested at vegetative, floral budding, full flowering, fresh fruiting and mature fruiting stages and dissected into stem, leaf and reproductive tissues and assayed for bioactive compounds by HPLC method. Hypericin, quercetin and quercitrin content in whole plant increased during course of ontogenesis and the highest level was reached in blooming stage. On the contrary, hyperoside content of whole plant decreased linearly with advancing of development stages and the highest level was observed at vegetative stage. Plants produced similar amount of chlorogenic acid at all stages of plant phenology except for mature fruiting at which the amount of this compound was decreased sharply. Among different tissues, reproductive parts accumulated the highest level of hypericin, quercetin and quercitrin, however, leaves produced substantially higher amount of chlorogenic acid and hyperoside. Rutin and apigenin-7-O-glucoside were detectable in all tissues only during fruit maturation. The presence and variation of these bioactive substances in H. origanifolium were reported for the first time.  相似文献   
43.
Venlafaxine is an approved antidepressant that is an inhibitor of both serotonin and norepinephrine transporters. Medical treatment with oral venlafaxine can be beneficial to depression due to reducing free radical production in the brain and medulla of depression- induced rats because oxidative stress may a play role in some depression. We investigated the effect of venlafaxine administration and experimental depression on lipid peroxidation and antioxidant levels in cortex brain, medulla and erythrocytes of rats. Thirty male wistar rats were used and were randomly divided into three groups. Venlafaxine (20 mg/kg) was orally supplemented to depression-induced rats constituting the first group for four week. Second group was depression-induced group although third group was used as control. Depressions in the first and second groups were induced on day zero of the study by chronic mild stress. Brain, medulla and erythrocytes samples were taken from all animals on day 28. Depression resulted in significant decrease in the glutathione peroxidase (GSH-Px) activity and vitamin C concentrations of cortex brain, glutathione (GSH) value of medulla although their levels were increased by venlafaxine administration to the animals of depression group. The lipid peroxidation levels in the three tissues and nitric oxide value in cortex brain elevated although their levels were decreased by venlafaxine administration. There were no significant changes in cortex brain vitamin A, erythrocytes vitamin C, GSH-Px and GSH, medulla vitamin A, GSH and GSH-Px values. In conclusion, cortex brain within the three tissues was most affected by oxidative stress although there was the beneficial effect of venlafaxine in the brain of depression-induced rats on investigated antioxidant defenses in the rat model. The treatment of depression by venlafaxine may also play a role in preventing oxidative stress. Abstract of the paper was submitted in 1st Ion Channels and Oxidative Stress Congress, 14–16 September 2006, Isparta, Turkey.  相似文献   
44.
This study was carried out to determine effects of composted hazelnut husk (CHH) on some chemical properties of soil and soil humic acid (HA). Compost application increases organic matter (OM) content of the soil considerably, OM value of 3.18% became 3.89% in 3 years time interval. Before application of compost, the soil pH was found to be 5.37, while after compost application it became 5.61. FTIR characteristics of humic acid/humic acid-like materials extracted from the original hazelnut husk, composted hazelnut husk and composted hazelnut husk amended soil have been investigated. C and O content of humic acid-like/humic acid materials were in the range of 41.4–50.8% and 37.8–50.5%, respectively. The N content of the humic acid/humic acid-like materials are in the expected range for humic materials which is 2–6%. Comparison of FTIR spectra of hazelnut husk and composted hazelnut husk humic acid-like fractions shows that both exhibit similar but not identical series of IR bands indicating the presence of the same functional groups in both samples. The only difference in the spectra seemed to be a decrement in the peak intensities of composted sample compared to uncomposted one. The similar differentiation of the intensities of IR bands of compost applied soil sample has also been observed. The FTIR spectral results show that the characteristics of composted material tend to become similar to that of soil humic acids characteristics in time.  相似文献   
45.
Data on population size, adult sex ratio, body size and mass are provided for a population of the turtle Emys orbicularis near Pazara?aç (Afyonkarahisar/Turkey). Using the mark-recapture method (triple catch), a population size of 664 turtles was estimated (95% confidence interval, range 332–996), corresponding to a density of 83 turtles per hectare (range 41.5–124.5). The adult sex-ratio was significantly skewed in favor of males (2.02 males: 1 female; P < 0.001). Almost all recorded specimens were adult (98.1%). Mean straight carapace length (SCL) and body mass (BM) of adult turtles were: SCL = 128.65 mm, BM = 345 g for males (n = 168) and SCL = 135.37 mm, BM = 463 g for females (n = 83).  相似文献   
46.
The six-transmembrane protein Stamp2 plays an important role in metabolically triggered inflammation and insulin action. We report that Stamp2 is expressed in human and mouse macrophages, is regulated upon differentiation or activation, acts as an anti-inflammatory protein, and regulates foam cell formation. Absence of Stamp2 results in significant increases in cellular NADPH levels, and both NADPH homeostasis and the exaggerated inflammatory response of Stamp2(-/-) macrophages are rescued by exogenous wild-type but not by a reductase-deficient Stamp2 molecule. Chemical and genetic suppression of NADPH production in Stamp2(-/-) macrophages reverts the heightened inflammatory response. Stamp2 is detected in mouse and human atherosclerotic plaques, and its deficiency promotes atherosclerosis in mice. Furthermore, bone marrow transplantation experiments demonstrated that Stamp2 in myeloid cells is sufficient to protect against atherosclerosis. Our data reveal a role of Stamp2 in controlling intermediary metabolites to regulate inflammatory responses in macrophages and in progression of atherosclerosis.  相似文献   
47.
48.
The effect of pre-treatment with 200 mM NaCl on the response of four barley cultivars (Hordeum vulgare L. cv. Bülbül-89, Kalaycı-97, Tarm-92 and Tokak-157/37) to UV-B radiation was investigated. Salt stress as well as UV-B irradiation led to a decrease of the total chlorophyll (chl) content in all cultivars, except in Kalaycı-97. While carotenoids are almost not affected by NaCl treatment, UV-B irradiation caused an increase by 5–20% of carotenoid content of all cultivars. UV-B induced damages of photosynthetic apparatus were estimated by the rate of photosynthetic electron transport measured by chl fluorescence and the rate of oxygen evolution, the latter being more affected. Pre-treatment with NaCl alleviated harmful effect of UV-B irradiation on F v/F m and ETR, but not on oxygen evolution. UV-B-induced and UV-B-absorbing compounds with absorption at 300 and 438 nm increased as a result of UV-B treatment. The level of stress marker proline increased considerably as a result of NaCl treatment, while UV-B irradiation resulted in a pronounced increase of the level of H2O2. MDA enhanced in the seedlings subjected to salt and UV-B stress. Established cross-acclimation to UV-B as a result of salt treatment could be due to the increased free proline and the level of UV-B absorbing compounds in barley seedlings subjected to NaCl.  相似文献   
49.
The aim of this study was to develop and characterize rh- IL-2 loaded chitosan-based nanogels for the healing of wound incision in rats. Nanogels were prepared using chitosan and bovine serum albumin (BSA) by ionic gelation method and high temperature application, respectively. Particle size, zeta potential, and polydispersity index were measured for characterization of nanogels. The morphology of nanogels was examined by using SEM and AFM. The IL-2 loading capacity of nanogels was determined using ELISA method. In vitro release of IL-2 from nanogels was performed using Franz diffusion cells. Artificial neural network (ANN) models were developed using selected input parameters (stirring rate, chitosan%, BSA%, TPP%) where particle size was an output parameter for IL-2 free nanogels. Wound healing effect of IL-2 loaded chitosan-TPP nanogel was evaluated by determining the malondialdehyde (MDA) and glutathione (GSH) levels of wound tissues in rats. The particle size of IL-2 loaded chitosan-TPP nanogels was found to be larger than that of IL-2 loaded BSA-based chitosan nanogels. Drug loading capacity of nanogels was found 100%?±?0.010 for both nanogels. IL-2 was released slowly after the initial burst effect. According to SEM and AFM imaging, BSA-chitosan nanogel particles were of nanometer size and presented a swelling tendency, and chitosan-TPP nanogel particles were found to be spherical and homogenously dispersed. IL-2 loaded chitosan-TPP nanogel was found suitable for improving wound healing because it decreased the MDA levels and increased the GSH levels wound tissues comparing to control group.  相似文献   
50.
The effect of configuration of activated sludge systems on heavy metal toxicity was investigated. Two bench-scale completely mixed activated sludge systems were operated identically in order to determine the toxic effects of Cr(VI), Zn(II) and industrial wastewater on the activated sludge biomass. One system was operated with an aerobic selector and the other without. Batch experiments based on OECD 209 (Organisation for Economic Cooperation and Development) were performed using a respirometer to find out potential toxicity reduction effect of an aerobic selector. The IC50 (concentration of a chemical that exhibits 50% respiration inhibition) values of Cr(VI), Zn(II) and industrial wastewater in the activated sludge were determined. Results indicated that the heavy metals and industrial wastewater caused less inhibitory effect on the selector activated sludge system in comparison to the conventional activated sludge system. Cr(VI) was found to exert higher inhibition on both systems.  相似文献   
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