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31.
Drug-induced differentiation of a rat glioma in vitro: II. The expression of S-100, a glial specific protein and steroid sulfatase 总被引:1,自引:0,他引:1
Amethopterin and 5-bromodeoxyuridine (BUdR) were used to induce morphological changes in cloned rat glioma (C6). The expression of S-100 protein, an acidic protein localized in glial cells, and steroid sulfatase, an ubiquitously distributed enzyme found in high concentration in glial cells, were followed during cell growth, from subculture to well into the stationary phase of control and drug-treated cultures. Amethopterin and BUdR differed in their effects on glioma morphology and in the expression of the biochemical parameters. Amethopterin coordinately stimualted both the production of S-100 protein and steroid sulfatase activity when cell division was inhibited during early logarithmic growth phase. BUdR stimulated steroid sulfatase activity but repressed production of S-100 protein. The results are discussed with respect to the mechanism of regulation of the differentiated state of tumor cells. 相似文献
32.
Kurpad AV Regan MM Varalakshmi S Gnanou J Lingappa A Young VR 《The American journal of clinical nutrition》2004,80(6):1526-1535
BACKGROUND: The 1985 FAO/WHO/UNU requirement for methionine in healthy adults consuming a cystine-free diet is 13 mg.kg(-1).d(-1). It is unclear whether this daily requirement is influenced by dietary cystine. OBJECTIVE: We assessed the effect of 2 intakes of cystine (5 and 12 mg.kg(-1).d(-1)) on methionine requirements in well-nourished Indian men by using 7 test methionine intakes (3, 6, 9, 13, 18, 21 and 24 mg.kg(-1).d(-1)) and the 24-h indicator amino acid oxidation (24-h IAAO) and balance (24-h IAAB) methods. We combined these data with those from an experiment with zero cystine intake and in which the exact same method was used. DESIGN: Two studies were performed in which a diet containing either 5 or 12 mg cystine.kg(-1).d(-1) was fed to 21 well-nourished Indian men over three 7-d periods. The 24-h IAAO and 24-h IAAB values were measured on day 7 with the use of a 24-h intravenous [13C]leucine tracer infusion. The breakpoints in the relation between these values and methionine intake in each study were assessed by two-phase linear regression. RESULTS: Breakpoints in the response curve were obtained at methionine intakes of 20 (95% Fiellers CI: 17, 26) and 10 (95% Fiellers CI: 8, 16) mg.kg(-1).d(-1) with cystine intakes of 5 and 12 mg.kg(-1).d(-1) intakes, respectively, which suggested a sparing effect of cystine. Although the 5- and 12-mg cystine breakpoints differed from one another, they did not differ significantly from that estimated previously with 0 mg cystine. CONCLUSION: Cystine may spare the methionine requirement in healthy men, although the amount of sparing is difficult to quantify. 相似文献
33.
Monosodium glutamate (MSG) was administrated chronically for 60 days to Wistar rats and 24 h rhythms of glucose, cholesterol, total protein and alkaline phosphatase were studied. MSG treatment was found to cause acrophase delays in the glucose and alkaline phosphatase rhythms and advances in acrophases of cholesterol and total protein levels. Amplitude and mesor values of these rhythms were found to be altered during MSG treatment. Glutamate levels in the brain were found to be significantly increased, which could alter these biochemical rhythms by modulating the transmission in retinohypothalamic tract and in the hypothalamic nuclei, probably including suprachiasmatic nuclei. 相似文献
34.
Sivakumar T Perumal P Kumar RS Vamsi ML Gomathi P Mazumder UK Gupta M 《The American journal of Chinese medicine》2004,32(4):531-539
Analgesic, antipyretic activity and toxicity study of the leaves of Bryonia laciniosa Linn. (Family: Cucurbitaceae) was evaluated in the standard animal models. The methanol extract of Bryonia laciniosa (MEBL) was evaluated by hot plate and acetic acid-induced writhing methods to assess analgesic activity. The antipyretic activity of the extract was also evaluated by normal body temperature and yeast-induced hyperpyrexia. The extract showed significant analgesic and antipyretic activity. The MEBL was further evaluated for toxicity at the doses of 125 and 250 mg/kg administered orally for 14 days in rats. At the end of experiments, the blood, liver function and kidney metabolism were observed. The hematological profile and different biochemical parameters such as SGOT, SGPT and ALP were estimated. The present study revealed that MEBL exhibited significant analgesic and antipyretic activity in the tested experimental animal models. The toxicity study indicates that the extract is not toxic at the tested doses. 相似文献
35.
36.
The effects of alpha-ketoglutarate (alpha-KG) on sodium valproate-induced hyperammonemia and hepatotoxicity were studied in biochemical experiments in rats. The levels of ammonia, urea, serum transaminases, hydroperoxides and thiobarbituric acid reactive substances were significantly increased in sodium valproate-treated rats. These levels were significantly decreased in alpha-KG- and sodium valproate-treated rats. Further, non-enzymatic (vitamins C and E) and enzymatic (superoxide dismutase and catalase) antioxidants were significantly decreased in sodium valproate-treated rats and were increased in alpha-KG- and sodium valproate-treated rats. These biochemical alterations during alpha-KG treatment could be due to (i) its ability to act as an ubiquitous collector of amino groups in body tissues, (ii) the participation of alpha-KG in the non-enzymatic oxidative decarboxylation in the hydrogen peroxide decomposition process and (iii) enhancing the proper metabolism of fats which could suppress oxygen radical generation and, thus, prevent the lipid peroxidative damages in rats. 相似文献
37.
The cytoprotective role of a low-molecular-weight heparin fragment studied in an experimental model of glomerulotoxicity 总被引:4,自引:0,他引:4
Abnormal glomerular glycosaminoglycan metabolism is involved in the onset of the morphological and functional aberrations of glomerulopathies. In the present study, a heparin derivative, low-molecular-weight heparin, was tested for its ability to afford renoprotection in an established model of experimental glomerulopathy. Two groups of male albino rats of the Wistar strain (140 +/- 10 g) received a single intravenous injection of adriamycin (7.5 mg/kg) to induce glomerulopathy, and one of them received low-molecular-weight heparin (Certoparin Sodium, Troparin; 300 microg/day/rat s.c.) treatment, commencing on day 8, for a week. Urinary protein/creatinine ratio, serum albumin, urea, uric acid and creatinine clearance were evaluated. Renal cell injury was assessed in terms of renal tissue lactate dehydrogenase, aminotransferases (aspartate and alanine transaminases) and alkaline phosphatase activities, as well as renal antioxidant status (superoxide dismutase, catalase and glutathione peroxidase, reduced glutathione, vitamins E and C). The kidney tissue was subjected to histopathologic examination. Low-molecular-weight heparin significantly reduced proteinuria and improved creatinine clearance and serum albumin levels in the rats with glomerulopathy. The significant rise in serum uric acid in the rats with glomerulopathy was reversed by low-molecular-weight heparin. Altered tissue enzyme activities in response to injury, oxidative stress challenged renal antioxidant system and abnormal renal histology were observed in the untreated nephrotic rats, while low-molecular-weight heparin treatment protected the nephrotic rats against these changes. Thus, in this study, low-molecular-weight heparin was evaluated for its role in combating glomerular injury, on the basis of some salient biochemical parameters, oxidative injury indices and histologic picture. The ability of low-molecular-weight heparin to restore glomerular anatamo-functional features in this nephrotoxic condition illuminates its multi-faceted renoprotective role. 相似文献
38.
Azibar Rodríguez-Iruretagoiena Ranju Chowdhury Ainara Gredilla Silvia Fdez-Ortiz deVallejuelo Alberto de Diego Santosh Kumar Sarkar Gorka Arana Juan Manuel Madariaga Perumal Venkatachalam 《Bulletin of environmental contamination and toxicology》2016,97(5):721-727
Absorption, accumulation and translocation of 12 trace elements in nine dominant mangrove plants in the Indian Sundarban Wetland revealed both organ-specific and site-specific characteristics. An overall enrichment of elements was recorded in rhizosediment, exceeding the prescribed effects range-low (ER-L) of consensus based sediment quality guidelines (SQGs) for Cu and Pb. Avicennia officinalis, A. alba, Ceriops decandra and Excoecaria agallocha exhibited unique potential for accumulating Al, Cd, Co, Cr, Cu, Ni, Mn and Zn and could be considered efficient accumulators. Maximum element accumulation in trunk bark (As 6.16, Cr 49.9, Co 2.67, Cu 91.00 and Zn 85.5 mg kg?1) and root/pneumatophore (Al 1000 and Fe 2430 mg kg?1) was recorded. Maximum bioconcentration factor (6.23) in A. officinalis and translocation factor (17.5 for Mn) in C. decandra distinguished their phytoremediation capacity. These halophytes could be used for trace element phytoremediation in stressed sites of Sundarban. 相似文献
39.
In this study, a Nd2O3@MIL(Fe)-88A composite was prepared through a hydrothermal method and used to detect dichlorvos. The XRD result demonstrated that the prepared sensor is highly crystalline in nature. The affinity of metal oxide and MIL(Fe)-88A could be utilised to overcome low stability and sensitivity owing to their synergistic and electronic effects. Differential pulse voltammetry (DPV) exhibits the electrocatalytic behaviour of Nd2O3@MIL(Fe)-88A; it functions at a lower potential at −0.5 to 0.8 V and has a wide linear range of 1–250 nM. It shows a very low detection limit of 0.92 nM with good sensitivity (4.42 mA nM−1) and selectivity. The developed Nd2O3@MIL(Fe)-88A sensor was successfully applied to detect dichlorvos in real analysis. The recovery range calculated for cabbage and orange extracts was 96–97% and 99.5–103.4%, respectively, and RSD% calculated for cabbage and orange extracts was from 1.40 to 3.39% and from 0.64 to 2.26%, respectively.A Nd2O3@MIL(Fe)-88A composite was prepared through a hydrothermal method and used to detect dichlorvos. 相似文献
40.