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101.
Adel AA Mohdaly Mohamed A Sarhan Iryna Smetanska Awad Mahmoud 《Journal of the science of food and agriculture》2010,90(2):218-226
BACKGROUND: Growing interest in the replacement of synthetic food antioxidants by natural ones has fostered research on vegetable sources and screening of raw materials to identify new antioxidants. The food‐processing industry generates substantial quantities of phenolic‐rich by‐products that could be valuable natural sources of antioxidants. In this study the antioxidant properties and total phenolic, flavonoid and flavonol contents of three industrial by‐products, sugar beet pulp, sesame cake and potato peel, extracted with various solvents were examined. Since different antioxidant compounds have different mechanisms of action, several methods were used to assess the antioxidant efficacy of extracts. RESULTS: Among the six solvents tested, methanol gave the highest extract yield of potato peel and sugar beet pulp, while diethyl ether gave the highest extract yield of sesame cake. Methanol exhibited the highest extraction ability for phenolic compounds, with total phenolics amounting to 2.91, 1.79 and 0.81 mg gallic acid equivalent g?1 dry weight in potato peel, sugar beet pulp and sesame cake extracts respectively, and also showed the strongest antioxidant capacity in the three assays used. All three methods proved that potato peel extract had the highest antioxidant activity owing to its high content of phenolic compounds and flavonoids. CONCLUSION: On the basis of the results obtained, potato peel, sugar beet pulp and sesame cake extracts could serve as natural antioxidants owing to their significant antioxidant activity. Therefore they could be used as preservative ingredients in the food and/or pharmaceutical industries. Copyright © 2009 Society of Chemical Industry 相似文献
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Selective lesion of the serotoninergic system diminished the synaptic uptake of 3H-L-glutamic acid and 3H-DL-aspartic acid, as well as the Na+(-dependent) binding of 3H-L-glutamic acid in the cortex and the brain stem. The data obtained suggest an ability of the serotoninergic system to modify presynaptic processes in amino-acidergic neurons of the CNS. 相似文献
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30 patients were exposed to interference currents (IC) alone (group 1) versus 34 patients treated with IC plus iodobromine baths (group 2). After IC action on the region of the kidney projection patients of group 1 experienced positive changes in cellular and humoral immunity providing an antiinflammatory effect. In group 2, the improvement was seen in renal and urinary functions, 24-h urinary excretion of oxalates and calcium diminished. Interference current proved beneficial in chronic pyelonephritis patients with latent inflammation. The combined therapy was effective in patients at high risk of lithogenesis. 相似文献
106.
A De Bellis A Bizzarro A Gattoni C Romano S Di Martino AA Sinisi S Abbadessa A Bellastella 《Canadian Metallurgical Quarterly》1995,80(7):2118-2121
Expression of intercellular adhesion molecule-1 (ICAM-1) and endothelial-leukocyte adhesion molecule-1 (ELAM-1) on endothelium can be considered a critical early step for leukocyte migration from blood to tissues during inflammatory processes. Increased circulating soluble ICAM-1 (sICAM-1) levels have been found in sera from patients with Graves' disease (GD) with or without ophthalmopathy. Serum soluble ELAM-1 (sELAM-1) levels have not been measured in these patients. The aim of this study was to clarify the behavior of sICAM-1 and sELAM-1 levels in patients with hyperthyroidism due to GD with or with or without ophthalmopathy and in hyperthyroid patients with toxic thyroid adenoma. We studied sICAM-1 and sELAM-1 levels in 130 subjects (age 23-54 yr), grouped as follows: group 1, 30 untreated hyperthyroid GD patients (21 females and 9 males) with active ophthalmopathy; group 2, 26 euthyroid GD patients (16 females and 10 males) with active ophthalmopathy; group 3, 33 hyperthyroid GD patients (22 females and 11 males) without ophthalmopathy; group 4, 11 untreated hyperthyroid patients (7 females and 4 males) with single toxic adenoma; and a control group of 30 healthy subjects (21 females and 9 males). sICAM-1 and sELAM-1 concentrations were measured by a sandwich enzyme linked immunosorbent assay (ELISA) method. Groups 1, 2, and 3 (P < 0.001 for all 3 groups) but not group 4 showed increased sICAM-1 levels compared with the control group. However, groups 1 and 2 (P < 0.001 for both) showed higher values of sICAM-1 than group 3, and group 1 showed higher sICAM-1 levels than group 2 (P < 0.002). Groups 1 and 2 (P < 0.001 for both) but not groups 3 and 4 showed sELAM-1 levels significantly higher than the control group and positively correlated to the severity score of Graves' ophthalmopathy (GO) (P < 0.002 for group 1 and < 0.01 for group 2). Our results confirm that increased sICAM levels in GD patients with or without ophthalmopathy (with higher levels in patients with GO) but not in hyperthyroid nonautoimmune patients may be the consequence of orbital and thyroid inflammation, and they also suggest that sICAM concentrations could reflect the degree of inflammatory activity. Increased sELAM-1 concentrations only, in patients with ophthalmopathy with or without hyperthyroidism significantly correlated to severity score of GO, suggest the measurement of sELAM-1 levels as a specific marker of endothelium activation in GO. 相似文献
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EA Lock Y Sani RB Moore MB Finkelstein MW Anders AA Seawright 《Canadian Metallurgical Quarterly》1996,70(10):607-619
Almost 40 years ago, it was reported that cattle-feed which had been extracted with hot trichloroethylene and then fed to calves produced renal injury and a fatal aplastic anaemia. The toxic factor was subsequently identified as S-(1,2-dichlorovinyl)-L-cysteine (DCVC). These original findings have been confirmed, a single intravenous dose of DCVC at 4 mg/kg, or 0.4 mg/kg intravenously per day administered for 10 days to calves produced aplastic anaemia, and renal injury after a single dose of 4 mg/kg. The toxicity to calves of a number of other haloalkene cysteine conjugates has been examined to ascertain whether, like DCVC, they produce bone marrow and renal injury. Intravenous administration of the N-acetyl cysteine conjugate of DCVC produced renal but not bone marrow injury at a molar equivalent dose to DCVC, indicating that the calf can deacetylate the mercapturic acid and further that sufficient chemical had reached the kidney to be a substrate for the enzyme cysteine conjugate beta-lyase. However, intravenous administration of the alpha-methyl analogue of DCVC, which cannot undergo metabolism via the enzyme cysteine conjugate beta-lyase, was without toxicity at doses about five-fold higher than DCVC. These latter findings provide strong evidence that metabolism of DCVC via the enzyme beta-lyase is necessary for bone marrow and renal injury to occur. The cysteine conjugates of perchloroethylene and hexachloro-1,3-butadiene(HCBD) when given intravenously to calves at molar equivalent doses to DCVC, or above, did not produce either bone marrow or renal injury. In contrast, intravenous administration of the cysteine conjugate of tetrafluoroethylene (TFEC) produced severe renal tubular injury in calves without affecting the bone marrow. In vitro studies with these haloalkene cysteine conjugates showed, like DCVC, that they were good substrates for calf renal cysteine conjugate beta-lyase and toxic to renal cells as judged by their ability to reduce organic anion and cation transport by slices of calf renal cortex and inhibit the renal enzyme glutathione reductase. Calves were also dosed either orally or intravenously with HCBD to assess its toxicity. HCBD at higher molar equivalent doses than DCVC produced mid-zonal necrosis in the liver, renal tubular necrosis but no bone marrow injury in calves. The key findings emerging from these studies are (1) that none of the other cysteine conjugates, at molar equivalent doses to DCVC and above, produce bone marrow injury in calves, (2) TFEC produced only renal injury, suggesting that sufficient of the other conjugates had not reached the kidney for metabolism by beta-lyase to produce cytotoxicity and (3) that HCBD itself is more toxic than its cysteine or mercapturic acid conjugate, suggesting that pharmaco-kinetics and disposition are important factors in determining the toxicity of these conjugates to calves. Further studies are needed to understand the basis for the selective toxicity of DCVC to the bone marrow of calves. 相似文献
110.