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11.
Cytotoxicity of 4 Aroclors (1016, 1242, 1254 and 1260) was compared in Chinese hamster ovary (CHO-K1) cells in Ham's F-12 medium. When parameters of toxicity were cell numbers or tissue protein, 50% lethality occurred at Aroclor concentrations between 30 and 45 ppm. An in vitro clonal assay with CHO-K1 cells was a sensitive indicator of cytotoxicity of the polychlorinated biphenyls (PCBs). From EC50 values (concentration that allowed 50% survival of formed colonies), cytotoxicity was lower with Aroclor 1016 (32 ppm) and higher with Aroclors 1254 (27 ppm) and 1260 (28 ppm). In cells exposed 24 h to a marginally cytotoxic dose (20 ppm) of each Aroclor, phospholipid (PL) thin-layer chromatography (TLC) showed an increase in phosphatidylcholine (PC) and a decrease in phosphatidylethanolamine (PE) and diphosphatidylglycerol (DPG). Neutral lipid (NL) TLC of cells given Aroclors 1242, 1254 or 1260 showed a 3–4-fold increase in triglyceride (TG) and a similar reduction in cholesteryl esters (CE); in contrast to Aroclor 1016 which produced no change in TG and a smaller (2-fold) reduction in CE. Cholesterol and free fatty acid fractions were unaffected by any of the Aroclors. The TG:PL ratio remained unchanged in cells given Aroclor 1016, but increased 3–4-fold with Aroclors 1242, 1254, or 1260. Compared to total values in the untreated controls, CHO-K1 cells contained less neutral lipid and more phospholipid only with Aroclor 1016.These results support the concept that differences in the behavior of Aroclor 1016 are related to its PCB composition. Changes in membrane PL and NL components, observed at marginally cytotoxic levels of each Aroclor, provided further evidence that the PCBs may affect membrane integrity and associated metabolic functions. 相似文献
12.
OBJECTIVE: Prevalence rates for child psychopathology in Denmark are unknown; and efficient screening and non-respondent analyses are essential for epidemiological purposes. METHOD: A multi-method strategy involving a two-step design: first screening of 621 children between the ages of 8-9 years attending mainstream education using the Child Behaviour Checklist (CBCL). Second, screen-positive probands and a sample of screen-negative probands were given in-depth child-psychiatric assessment. In cases of non-respondents, children were assessed by teachers. RESULTS: CBCL screening results were compared with case status in clinical assessment. A positive predictive value of 0.25 and a correct classification rate (CCR) of 0.72 were obtained. The teacher interviews, used in cases of non-respondents, had a CCR of 0.87. According to DSM-IV criteria, the prevalence rate of psychiatric disorders was 10.l% [95% CI; 7.0-13.2]. CONCLUSIONS: The CBCL proved an effective screening tool. The brief interview with teachers is a valid assessment of psychiatric disorders among non-respondents. 相似文献
13.
14.
Aminoalcohols differ in mammalian toxicity at least in part based upon their ability to alter the metabolism of phospholipids and to cause depletion of the essential nutrient choline in animals. This study examined the incorporation of diisopropanolamine (DIPA) into phospholipids (PLs) and effects of DIPA upon choline uptake and phospholipid synthesis in Chinese hamster ovary (CHO) cells. Results were compared to those of a related secondary alcohol amine, diethanolamine (DEA), whose systemic toxicity is closely associated with its metabolic incorporation into PLs and depletion of choline pools. DIPA caused a dose-related inhibition of (3)H-choline uptake by CHO cells that was approximately 3-4 fold less potent, based upon an IC50, than that reported for DEA. DIPA, in contrast to DEA, did not cause changes in the synthesis rates of (33)P-phosphatidylethanolamine, (33)P-phosphatidylcholine or (33)P-sphingomyelin at either non-toxic or moderately toxic concentrations. Only approximately 0.004%, of administered (14)C-DIPA was metabolically incorporated into PLs, over 30-fold less than the incorporation of (14)C-DEA under similar conditions. Overall, these data and previous pharmacokinetic and toxicity data obtained in vivo suggests that DIPA is distinct from DEA and lacks significant choline and PL metabolism related toxicity in animals. 相似文献
15.
16.
Ari A. Mennander 《The Journal of thoracic and cardiovascular surgery》2018,155(4):1659-1660
17.
Sorrel T. Burden Debra J. Jones Matthew Gittins Joanne Ablett Michael Taylor Christopher Mountford Jonathan Tyrrell-Price Clare Donnellan Fiona Leslie Tim Bowling Simon Gabe Farooq Rahman Stephen P. McKenna Jeanette Wilburn Alice Heaney Philip Allan Simon Lal 《Clinical nutrition (Edinburgh, Scotland)》2019,38(3):1433-1438
18.
Chenni A Yahia DA Boukortt FO Prost J Lacaille-Dubois MA Bouchenak M 《Journal of ethnopharmacology》2007,109(2):207-213
The present study was designed to explore the possible antioxidant and hypolipidemic effects of the aqueous extract of Ajuga iva (0.5% in the diet) in rats fed a high-cholesterol (1%) diet (HCD). The results indicated that the HCD-Ai versus HCD treatment led to many changes in biochemical parameters. They showed a decrease of plasma total cholesterol (TC) and VLDL-cholesterol but an increase of HDL(2)-cholesterol. The triacylglycerol contents were reduced in plasma and in VLDL. The lipid peroxidation determined by TBARS was decreased by 75% in plasma. TBARS in liver, heart and kidneys were highly reduced excepted in the adipose tissue. Ajuga iva treatment enhanced superoxide dismutase activity in liver and kidney. Glutathione reductase activity was lowered in adipose tissue but increased in liver and in kidney. A significant increase was noted in glutathione peroxidase activity in liver, heart and kidney but a low value in adipose tissue was observed. In conclusion, the present study demonstrates that in addition to its potent TG and TC-lowering effects, Ajuga iva is effective in improving the antioxidant status by reducing lipid peroxidation in plasma and tissues and enhancing the antioxidant enzymes in rats fed high-cholesterol diet. Furthermore, Ajuga iva may reduce intestinal cholesterol absorption. 相似文献
19.
Lilton R.C. Martinez Raul D. Santos Márcio H. Miname Débora F. Deus Emerson S. Lima Raul C. Maranhão 《Metabolism: clinical and experimental》2013
Objective
In familial hypercholesterolemia (FH), the metabolism and anti-atherogenic functions of HDL can be affected by the continuous interactions with excess LDL amounts. Here, lipid transfers to HDL, an important step for HDL intravascular metabolism and for HDL role in reverse cholesterol transport (RCT) were investigated in FH patients.Methods
Seventy-one FH patients (39 ± 15 years, LDL-cholesterol = 274 ± 101; HDL-cholesterol = 50 ± 14 mg/dl) and 66 normolipidemic subjects (NL) (38 ± 11 years, LDL-cholesterol = 105 ± 27; HDL-cholesterol = 52 ± 12 mg/dl) were studied. In vitro, lipid transfers were evaluated by incubation of plasma samples (37 °C, 1 h) with a donor lipid nanoemulsion labeled with 3H-triglycerides (TG) and 14C-unesterified cholesterol (UC) or with 3H-cholesteryl ester (EC) and 14C-phospholipids (PL). Radioactivity was counted at the HDL fraction after chemical precipitation of apolipoprotein (apo) B-containing lipoproteins and the nanoemulsion. Data are % of total radioactivity measured in the HDL fraction.Results
Transfer of UC to HDL was lower in FH than in NL (5.6 ± 2.1 vs 6.7 ± 2.0%, p = 0.0005) whereas TG (5.5 ± 3.1 vs 3.7 ± 0.9%, p = 0.018) and PL (20.9 ± 4.6 vs 18.2 ± 3.7 %, p = 0.023) transfers were higher in FH. EC transfer was equal. By multivariate analysis, transfers of all four lipids correlated with HDL-cholesterol and with apo A-I.Conclusion
FH elicited marked changes in three of the four tested lipid transfers to HDL. The entry of UC into HDL for subsequent esterification is an important driving force for RCT and reduction of UC transfer to HDL was previously associated to precocious coronary heart disease. Therefore, in FH, HDL functions can be lessened, which can also contribute to atherogenesis. 相似文献20.
Ganesan Pushpavalli Chinnadurai VeeramaniKodukkur Viswanathan Pugalendi 《Food and chemical toxicology》2010
Chrysin is a flavonoid that exists in nature and is the major component of some traditional medicinal herbs. We investigated the hepatoprotective and antihyperlipidaemic potential of chrysin against d-galactosamine (a single intraperitoneal injection 400 mg/kg BW) induced hepatotoxicity in male albino Wistar rats. d-GalN rats exhibited an increased hepato and nephro toxicity marker activities aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and gamma glutamyl transpeptidase and total bilirubin level while urea, uric acid and creatinine and lipid profile. It also negatively affected the serum total protein, albumin and A/G ratio. Rats treated with chrysin at different concentrations (25, 50 and 100 mg/kg BW) caused a significant improvement in serum protein level, decreased hepato and nephro toxicity markers. It also decreased the levels of very low density lipoprotein cholesterol and low density lipoprotein cholesterol while high density lipoprotein cholesterol significantly increased. It also decreased the levels of total cholesterol, phospholipids, triglycerides, free fatty acids in the plasma and tissues of liver and kidney. The effect of chrysin (25 mg/kg) is comparable with silymarin, a known hepatoprotective drug. Chrysin thus exhibits hepatoprotective and antihyperlipidaemic activity. 相似文献