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Plasma Cholesterol Concentrations (plasma + cholesterol_concentration)
Selected AbstractsEffect Of Plasma Cholesterol On Red Blood Cell Oxygen TransportCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 12 2000Henry Buchwald SUMMARY 1. Oxygen (O2) transfer from the blood to tissues is a function of the red blood cell (RBC) O2 saturation (SO2), the plasma O2 content being negligible. Under conditions of increased tissue O2 demand, the SO2 of arterial blood does not change appreciably (97%); however, the SO2 of mixed venous blood, equal to that of the perfused tissues, can go as low as 20%. 2. Tissue O2 availability is limited by the exposure time to a RBC, which decreases under conditions of maximum stress (< 1 s). If the O2 unloading time was to increase significantly, because of a decrease in the RBC diffusion constant or an increase in the RBC membrane thickness, the RBC O2 unloading time would exceed tissue (e.g. cardiac) transit time and O2 transfer would be impaired. 3. Cholesterol constitutes the non-polar, hydrophobic lipid of the enveloping layer of the RBC membrane. As the cholesterol content of the RBC increases, the fluidity of the membrane decreases and the lipid shell stiffens. 4. Early studies demonstrated that high blood cholesterol concentrations were associated with reduced blood O2 transport; in essence, the haemoglobin dissociation curve was shifted to the left. 5. Current investigations have shown that the cholesterol RBC membrane barrier to O2 diffusion delayed O2 entry into the RBC during saturation and delayed O2 release from the RBC during desaturation. In an analysis of 93 patients divided by their cholesterol concentration into five groups, the percentage change in blood O2 diffusion was inversely proportional to the cholesterol concentration. 6. The RBC membrane cholesterol is in equilibrium with the plasma cholesterol concentration. It stands to reason that as the plasma cholesterol increases, the RBC membrane becomes impaired and O2 transport is reduced. 7. The implications of this new perspective on O2 transport include the ability to increase tissue oxygenation by lowering plasma cholesterol. [source] Endothelial dysfunction, subangiographic atheroma, and unstable symptoms in patients with chest pain and normal coronary arteriogramsCLINICAL CARDIOLOGY, Issue 9 2000Jonathan R. Clague M.D. Abstract Background: Patients with chest pain and normal coronary arteriograms (CPNA) may present with unstable symptoms and other evidence of ischemia during clinical follow-up. Although repeat angiography usually proves negative, functional assessment of coronary vasomotor abnormalities may provide additional pathophysiologic information. Hypothesis: The study was undertaken to evaluate the relationship between endothelial dysfunction and subangiographic atheroma in patients with CPNA undergoing repeat angiography because of unstable symptoms. Methods: We investigated nine patients with CPNA (8 women, mean age 57 ± 9 years) undergoing repeat angiography because of unstable anginal symptoms. After normal angiography, simultaneous coronary epicardial and microvascular vasomotor responses to intracoronary vasodilators [acetylcholine (10,6 M), adenosine (18 ,g) and nitroglycerin (300 ,g)] were investigated in the left anterior descending artery using quantitative angiography and Doppler flow measurements. The presence of subangiographic atheroma was assessed by intravascular ultrasound. Results: Three patients demonstrated proximal and distal epicardial vasoconstriction and a reduction in coronary flow in response to acetylcholine, indicating concordant epicardial and microvascular endothelial dysfunction. These changes were associated with chest pain and ischemic electrocardio-graphic changes in two patients. None of the remaining patients suffered chest pain in response to intracoronary acetylcholine. Six patients had significant subangiographic disease (intimal thickness >0.3 mm) on intravascular ultrasound imaging, and multivariate analysis indicated a significant relationship (R2 = 0.89, overall p = 0.001) between the extent of subangiographic disease and both plasma cholesterol concentration and hypertensive history. No significant relationship was demonstrated between endothelial dysfunction and the extent of subangiographic disease. Conclusion: Concordant epicardial and microvascular endothelial dysfunction may be pathophysiologically and clinically significant in unstable patients with CPNA but does not appear to be directly related to the extent of subangiographic atheroma. [source] Cholesterol metabolism in 8 to 12-year-old children born preterm or at termACTA PAEDIATRICA, Issue 5 2003M Mortaz Studies in animals have indicated that cholesterol metabolism is susceptible to manipulation by diet and growth in early life. In humans, low birthweight has been associated with increased risk of coronary heart disease. Aim: To establish whether plasma lipids and indicators of cholesterol absorption, synthesis and breakdown differ in children born preterm and at term. Methods: Plasma total cholesterol, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, triacylglycerols, apolipoprotein A1, apolipoprotein B, lathosterol (indicator of cholesterol synthesis), campesterol (indicator of cholesterol absorption), 7-, hydroxycholesterol (indicator of cholesterol breakdown) were measured in up to 407 children born preterm and 36 children born at term. Results: Children born preterm had lower cholesterol synthesis (p= 0.002) and lower cholesterol breakdown (p < 0.001) than those born at term, but their plasma cholesterol concentration was not significantly different. After adjusting for current size, birthweight and gestational age were significantly related to plasma lathosterol and 7-, hydroxycholesterol. However, when both birthweight and gestational age were adjusted, only gestational age remained significant. There were no significant differences in plasma campesterol between the two groups. Conclusion: Being born preterm may have a long-term effect on cholesterol metabolism in children 8,12 y later. Those born prematurely had lower cholesterol synthesis and breakdown, but their plasma cholesterol concentration was similar at this age. These parameters need to be studied in older cohorts. [source] Hypolipidaemic effects of potato protein and fish protein in pigsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 4 2009J. Spielmann Summary This study was performed to assess the effects of potato protein and fish protein on concentrations of lipids in plasma and lipoproteins and the expression of genes involved in lipid metabolism in pigs used as an animal model. Therefore, 27 young male pigs with an average body weight of 22 kg were fed diets supplemented with protein extracted from potatoes (containing 849 g protein/kg dry matter), Alaska Pollack fillet as a source of fish protein (containing 926 g crude protein/kg dry matter) or casein which was used as control, for 3 weeks. Diets were formulated to supply identical amounts of each protein to the pigs by the three protein sources, namely 116 g/day in first week and 150 g/day in the second and third week. Pigs fed potato protein had lower concentrations of cholesterol in plasma and LDL than pigs fed casein (p < 0.05); no effect was observed on concentrations of HDL cholesterol and triglycerides. Pigs fed fish protein had lower cholesterol concentrations in plasma, LDL and HDL, and lower triglyceride concentrations in triglyceride-rich lipoproteins than pigs fed casein (p < 0.05). mRNA concentrations of genes involved in bile acid synthesis and cholesterol uptake were higher in pigs fed fish protein than in pigs fed casein (p < 0.05); no effect on these genes was observed in pigs fed potato protein. Expression of genes involved in lipogenesis and fatty acid oxidation was not altered by fish protein. In conclusion, this study shows that fish protein and potato protein lower plasma cholesterol concentrations in pigs. The hypocholesterolaemic effect of fish protein might be in part caused by a stimulation of bile acid synthesis; the reason for the hypocholesterolaemic effect of potato protein requires further elucidation. [source] Consumption of raw brown onions variably modulate plasma lipid profile and lipoprotein oxidation in pigs fed a high-fat dietJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2005Nicholas K Gabler Abstract This study was undertaken to determine the effects of two commercially available brown onion varieties, ,Cavalier' and ,Destiny', supplemented at two different levels, on blood lipid and oxidative status using the pig as a model. Twenty-five female cross-bred pigs were allocated to one of five dietary treatments that consisted of a high-fat control diet with no onion added, a low onion dose of 10 g onion MJ,1 DE and a high dose of 25 g onion MJ,1 DE for each variety of onion. Supplementation with ,Destiny' onion resulted in a 21% (p < 0.05) reduction in the averaged fasted and postprandial plasma triacylglyceride (TG) measurements taken over the six-week period in comparison with the control pigs. The average fasting and postprandial plasma cholesterol concentrations were significantly reduced by 5.5 and 12.4% in pigs that consumed the low and high dose of ,Destiny' onion, respectively (p < 0.010), while ,Cavalier' was only effective at lowering cholesterol levels by 10% at the lower dose of supplementation. Inhibition in the rate of serum lipoprotein oxidation, measured as lag time, was increased by 23% (p < 0.05) in plasma obtained from pigs that consumed ,Cavalier' compared with the control and ,Destiny' onion diets. These data indicate that onion consumption level may provide a dietary means of manipulating some of the risk indices associated with coronary heart disease, but the responses varied with type and dose of onion. Copyright © 2004 Society of Chemical Industry [source] Lack of genetic association between cholesteryl ester transfer protein and Japanese sporadic Alzheimer's diseasePSYCHOGERIATRICS, Issue 4 2006Akiyoshi KITAJIMA Abstract Background:, Cholesteryl ester transfer protein regulates the plasma high density lipoprotein cholesterol level, which is considered to play an antiatherogenic role in humans. The presence of apolipoprotein E epsilon4 allele is a strong risk factor for developing Alzheimer's disease (AD). Since apolipoprotein E is a regulator of lipid metabolism, it is reasonable to assume that lipids play important roles in the pathogenesis of AD. Methods:, We studied the relationship between polymorphisms of the cholesteryl ester transfer protein gene and risk for AD, analyzing two common polymorphisms of the gene and the relationship between them and plasma cholesterol level control samples. Results:, These polymorphisms showed no association with risk for AD. In rs5882, there was no significant difference in the mean plasma cholesterol concentrations found between patients with the A/A, A/G and G/G genotype. For rs2303790, no significant difference in the mean baseline cholesterol concentrations was found between patients with the A/A genotype and carriers of the G allele. Conclusion:, Our study indicates that these polymorphisms, rs5882 and rs2303790 were not associated with risk for AD. We also pointed out that these two polymorphisms do not affect plasma cholesterol levels in our Japanese AD samples. [source] Effects of feeding fermented fish on egg cholesterol content in hensANIMAL SCIENCE JOURNAL, Issue 1 2009Teck-Chwen LOH ABSTRACT This study was conducted to investigate the effects of feeding fermented fish (FF) to layers on laying performance, and polyunsaturated fatty acid and cholesterol levels in eggs and plasma. A total of 96, 13-week-old Babcock B380 pullets were used in this study. They were randomly assigned to four numerically equal groups with eight replicates per treatment, three birds per replicate. All the birds were housed in individual cages. The dietary treatments were: Control diet, without FF; FF3 diet containing 3% (w/w) FF, FF6 diet containing 6% (w/w) FF and FF9 diet containing 9% (w/w) FF. The study was carried out for 16 weeks inclusive of two weeks of adjustment. Weekly feed intake and egg production were recorded. Blood plasma cholesterol and fatty acid profiles were assayed at the end of the experiment. FF did not enhance (P > 0.05) egg mass but (P < 0.05) decreased egg weight slightly. However, egg yolk cholesterol and plasma cholesterol concentrations were reduced (P < 0.05) by FF. The n-6:n-3 fatty acids ratio in the egg yolk (Control = 7.9, FF9 = 6.2) and plasma (Control = 10.6, FF9 = 6.2) were decreased by feeding FF. Moreover, FF was able to increase (P < 0.05) the docosahexaenoic acid (DHA) concentrations in egg yolk and plasma. In conclusion, this study demonstrated that FF increased DHA and reduced egg yolk cholesterol in poultry eggs. [source] | |||||||||||||