Estimation of Mathematical Models Accuracy for Calculation of LDL-Cholesterol Concentration

SummaryPlatelet aggregation, platelet lipid composition and plasma lipoprotein concentrations were measured each week in a group of seventeen alcoholics, without overt liver disease, for one month, following acute, total alcohol withdrawal. The platelets were initially hypoaggregable but, within 1-2 weeks of cessation of drinking, they became hyperaggregable and then gradually returned towards normal values. Hyperaggregability could not be explained by increases in either the cholesterol or the arachidonic acid content of the platelets. Plasma very-low-density lipoprotein cholesterol levels remained high throughout the study, but the initially raised levels of high-density lipoprotein (HDL) cholesterol fell by 26%. Low-density lipoprotein (LDL) cholesterol concentration rose by 10% after two weeks of withdrawal but then returned to about the starting level. The resulting changes in the plasma LDL-cholesterol: HDL-cholesterol ratio, which had increased by more than 50% after two weeks of abstinence, essentially paralleled the time course of enhanced platelet reactivity in all but four of the alcoholics. These findings suggest that alterations in plasma lipoprotein concentrations during acute alcohol withdrawal may be a contributory factor to the haemostatic disorders present in such patients.

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The role of sex steroids in the regulation of insulin sensitivity and serum lipid concentrations during male puberty: a prospective study with a P450-aromatase inhibitor

Acta Endocrinologica ◽

10.1530/eje.0.1460339 ◽

2002 ◽

pp. 339-346 ◽

Cited By ~ 21

Author(s):

S Wickman ◽

T Saukkonen ◽

L Dunkel

Keyword(s):

Insulin Sensitivity ◽

Aromatase Inhibitor ◽

Sex Steroids ◽

Ldl Cholesterol ◽

Density Lipoprotein ◽

Treated Group ◽

Lipoprotein Cholesterol ◽

Cholesterol Concentration ◽

Igf I ◽

Letrozole Treatment

OBJECTIVE: Our purpose was to study the sex steroid-mediated changes in serum insulin and lipid concentrations in boys during puberty. DESIGN AND METHODS: We treated boys with constitutional delay of puberty either with testosterone plus placebo or with testosterone plus an aromatase inhibitor, letrozole, which inhibits the conversion of androgens to oestrogens. We demonstrated previously that during treatment with testosterone plus letrozole the increase in testosterone concentration was more than 5-fold higher than during treatment with testosterone plus placebo. The concentrations of 17beta-oestradiol, IGF-I and IGF-binding protein-3 increased during testosterone-plus-placebo treatment, but during testosterone-plus-letrozole treatment the concentrations remained unchanged. These divergent changes in the two groups enabled us to study the effects of sex steroids and GH on insulin sensitivity and lipid concentrations. RESULTS: The insulin concentration in the testosterone-plus-placebo-treated group did not change. In contrast, in the testosterone-plus-letrozole-treated group, the concentration decreased during letrozole treatment, indicating improved insulin sensitivity. Changes in insulin and IGF-I concentrations within 12 and 18 months were correlated. In the testosterone-plus-placebo-treated group, the high-density lipoprotein cholesterol concentration did not change but in the testosterone-plus-letrozole-treated group the concentration decreased. The concentrations of low-density lipoprotein cholesterol (LDL-cholesterol) and triglycerides did not change in either of the groups. CONCLUSIONS: The findings indicate that androgens do not directly alter insulin sensitivity in boys during puberty. In contrast, the observations suggest tight regulation of glucose--insulin homeostasis by GH in boys at this stage. Furthermore, our findings indicate that sex steroids do not significantly participate in the regulation of serum concentrations of LDL-cholesterol or triglycerides in boys during early and mid-puberty.

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THE CLINICAL SIGNIFICANCE OF THE DAILY MONITORING OF HOLTER ECG IN CHRONIC GLOMERULONEPHRITIS AT THE PREDIALYSIS STAGE OF THE DISEASE

The Russian Archives of Internal Medicine ◽

10.20514/2226-6704-2019-9-1-44-51 ◽

2019 ◽

Vol 9 (1) ◽

pp. 44-51

Author(s):

I. T. Murkamilov ◽

I. S. Sabirov ◽

V. V. Fomin ◽

Zh. A. Murkamilova ◽

A. I. Sabirova ◽

...

Keyword(s):

Heart Rate ◽

Ldl Cholesterol ◽

Clinical Importance ◽

Holter Monitoring ◽

Cardiovascular Complications ◽

Cholesterol Concentration ◽

Chronic Glomerulonephritis ◽

Daily Monitoring ◽

Daily Excretion ◽

Laboratory Examinations

This article presents the results of our own research: comprehensive clinical and laboratory examinations, including data from the daily Holter monitoring of the electrocardiogram (DMEKG) in 169 patients with chronic glomerulonephritis at the predialysis stage of the disease. According to the DMEKG, 60.3% of the persons examined by us had episodes of supraventricular group extrasystoles, and ventricular group extrasystoles in 28.9%. In addition, 11.2% of patients had atrial ventricular blockade (incomplete / partial), 8.8% had atrial fibrillation and painless ischemia in an amount of from 1 to 3 episodes per day in 14.7%. Depending on the average heart rate (HR) according to the DMEKG, patients with chronic glomerulonephritis were divided into two subgroups. Subgroup “A” included 38 patients with heart rate less than or equal to 70 beats / min, in subgroup “B” — 131 patients with a heart rate of more than 70 beats / min. With equal values of uric acid, total cholesterol cholesterol, HDL cholesterolcholesterol, TG, plasma creatinine and blood fibrinogen in subgroup “B” there was a statistically significant increase in LDL cholesterol concentration(3.58 (2.74; 5.54) mmol / l vs. 2, 82 (2.30; 3.86) mmol / l; p <0.05) and a decrease in the calculated GFR (70.4 (48.8; 96.3) ml / min vs. 85.7 (31.5; 103,1) ml / min; p <0.05) compared with subgroup “A”. In the subgroup “B” a tendency was observed to increase the degree of daily excretion of protein with urine. The data obtained confirm the fact that the conduct of the DMEKG with the analysis of heart rate is of significant clinical importance for the diagnosis of cardiovascular disorders and the p revention of cardiovascular complications in chronic glomerulonephritis at the predialysis stage of the disease.

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Lipoprotein Signatures of Cholesteryl Ester Transfer Protein and HMG-CoA Reductase Inhibition

10.1101/295394 ◽

2018 ◽

Cited By ~ 1

Author(s):

Johannes Kettunen ◽

Michael V. Holmes ◽

Elias Allara ◽

Olga Anufrieva ◽

Pauli Ohukainen ◽

...

Keyword(s):

Apolipoprotein B ◽

Ldl Cholesterol ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Triglyceride Composition ◽

Cholesterol Concentration ◽

Resonance Spectroscopy ◽

Low Density ◽

Triglyceride Content ◽

Cetp Inhibition

AbstractBackgroundCETP inhibition reduces vascular event rates but confusion surrounds its low-density lipoprotein (LDL)-cholesterol effects. We sought to clarify associations of genetic inhibition of CETP on detailed lipoproteins.Methods and ResultsWe used variants associated withCETP(rs247617) andHMGCR(rs12916) expression in 62,400 Europeans with detailed lipoprotein profiling from nuclear magnetic resonance spectroscopy. Genetic associations were scaled to 10% lower risk of coronary heart disease (CHD). Associations of lipoprotein measures with risk of incident CHD in three population-based cohorts (770 cases) were examined.CETPandHMGCRhad near-identical associations with LDL-cholesterol concentration estimated by Friedewald-equation.HMGCRhad a relatively consistent effect on cholesterol concentrations across all apolipoprotein B-containing lipoproteins.CETPhad stronger effects on remnant and very-low-density lipoprotein cholesterol but no effect on cholesterol concentrations in LDL defined by particle size (diameter 18–26 nm) (-0.02SD 95%CI: -0.10, 0.05 forCETPversus -0.24SD, 95%CI -0.30, -0.18 forHMGCR).CETPhad profound effects on lipid compositions of lipoproteins, with strong reductions in the triglyceride content of all highdensity lipoprotein (HDL) particles. These alterations in triglyceride composition within HDL subclasses were observationally associated with risk of CHD, independently of total cholesterol and triglycerides (strongest HR per 1-SD higher triglyceride composition in very-large HDL 1.35; 95%CI: 1.18, 1.54).ConclusionCETP inhibition does not affect size-specific LDL cholesterol but may lower CHD risk by lowering cholesterol in other apolipoprotein-B containing lipoproteins and lowering triglyceride content of HDL particles. Conventional composite lipid assays may mask heterogeneous effects of lipid-altering therapies.

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Validity of animal models for the cholesterol-raising effects of coffee diterpenes in human subjects

Proceedings of The Nutrition Society ◽

10.1017/s0029665199000725 ◽

1999 ◽

Vol 58 (3) ◽

pp. 551-557 ◽

Cited By ~ 18

Author(s):

Baukje de Roos ◽

Janet K. Sawyer ◽

Martijn B. Katan ◽

Lawrence L. Rudel

Keyword(s):

Animal Model ◽

Total Cholesterol ◽

Mechanism Of Action ◽

Serum Lipids ◽

Animal Species ◽

Ldl Cholesterol ◽

Human Subjects ◽

Plasma Lipoproteins ◽

Cholesterol Concentration ◽

Green Monkeys

Cafestol and kahweol, coffee lipids present in unfiltered coffee brews, potently increase LDL-cholesterol concentration in human subjects. We searched for an animal species in which cafestol similarly increases LDL-cholesterol. Such an animal model could be used subsequently as a model to study the mechanism of action of cafestol and kahweol. Cafestol and kahweol increased serum lipids in African green monkeys (Cercopithecus aethiops), cebus (Cebus apella) and rhesus (Macaca mulatta) monkeys, hamsters, rats and gerbils differently from the increase in human subjects. In African green monkeys, the rise in total cholesterol was less pronounced than that in human subjects. In addition, the increase in total cholesterol was predominantly due to a rise in HDL-cholesterol rather than LDL-cholesterol. Thus, the rise in plasma lipids might illustrate the mechanism in these monkeys rather than the mechanism in human subjects. In other animal species, cafestol and kahweol did not raise cholesterol consistently. The variability in effects on serum lipids could not be explained by the mode of administration or dose of diterpenes, nor by the amount of cholesterol in the diet. In conclusion, we did not find an animal model in which cafestol and kahweol elevate plasma lipoproteins to the same extent as in human subjects. For the time being, therefore, studies on the mechanism of action should be done preferably in human subjects.

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Abstract 186: Reduction Of High density lipoprotein Cholesterol After Successfull Dietary Intervention Is Not Accompanied By A Change In Reverse Cholesterol Transport

Circulation ◽

10.1161/circ.116.suppl_16.ii_15-b ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Rudolf Poledne

Keyword(s):

Reverse Cholesterol Transport ◽

Ldl Cholesterol ◽

Dietary Cholesterol ◽

Saturated Fat ◽

Hdl Cholesterol ◽

Cholesterol Concentration ◽

Cholesterol Transport ◽

High Cholesterol ◽

Unsaturated Fat ◽

Low Cholesterol

Substitution of dietary saturated fat by unsaturated fat and the reduction of dietary cholesterol intake leads to a decrease of LDL cholesterol concentration accompanied usually by a decrease of HDL cholesterol. Method: 18 young male volunteers were fed for 4 weeks either a high cholesterol saturated fat diet or low cholesterol and unsaturated fat diet in crossover design. At the end of both experimental periods, the lipoprotein concentration was determined. In addition, the reverse cholesterol transport from 14 C cholesterol labeled macrophages in tissue cultures was analyzed. Reverse cholesterol transport was calculated as the percentage of radioactivity released from pre-labeled cells to incubation media with serum of each individuals. Results: Highly significant decrease of LDL cholesterol after the unsaturated fat diet was accompanied by a significant decrease of the HDL cholesterol from 1.25 mmol/l to 1.05 mmol/l. Reverse cholesterol transport did not significantly change when the data of high cholesterol saturated fat diet (9.97 ± 1.45) and low cholesterol unsaturated fat diet (9.53 ± 1.41) were compared. There was no correlation between data of the decrease of HDL cholesterol concentration and change in reverse cholesterol transport. Conclusion: We conclude that dietary treatment by hypocholesterolemic diet accompanied by a reduction of HDL cholesterol does not lead to the decrease in reverse cholesterol transport.

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Hypertriglyceridemia and Lower LDL Cholesterol Concentration in Relation to Apolipoprotein E Phenotypes in Myotonic Dystrophy

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100028675 ◽

1989 ◽

Vol 16 (1) ◽

pp. 129-133 ◽

Cited By ~ 8

Author(s):

Sital Moorjani ◽

Daniel Gaudet ◽

Claude Laberge ◽

Marie Christine Thibault ◽

Jean Mathieu ◽

...

Keyword(s):

Myotonic Dystrophy ◽

Ldl Cholesterol ◽

Plasma Cholesterol ◽

Plasma Lipid ◽

Cholesterol Concentration ◽

Plasma Triglycerides ◽

Ldl Particles ◽

Vldl Cholesterol ◽

Apo E

ABSTRACT:Plasma lipid, lipoprotein levels and apolipoprotein apo E phenotypes were determined in 70 patients with myotonic dystrophy (MyD) and 81 controls. Marked differences were noticed in the apo E phenotype frequencies between the two groups. Plasma triglycerides and VLDL cholesterol were higher in MyD than controls, but only the latter was related to differences in the apo E phenotypes between two groups. Accordingly, the ratio of VLDL cholesterol/plasma triglycerides was increased significantly in MyD, suggesting accumulation of intermediary density particles due to lower affinity of E2 containing lipoproteins for lipoprotein cell receptors. The LDL cholesterol concentration was lower in MyD than controls and was related to differences in the apo E phenotype frequencies between the two groups. These results indicate increased removal of LDL particles in the apo E2 phenotypes, perhaps due to upregulation of LDL (B, E) receptor activity. Plasma cholesterol and HDL cholesterol concentrations were similar in both groups. Another feature of the study was lower levels of plasma cholesterol, triglycerides, VLDL and LDL cholesterol in the homozygous E4:E4 phenotype. These results suggest increased clearance rate of both VLDL and LDL particles and support the concept that apo E4-containing lipoproteins have higher in vivo affinity for ape E and/or B, E receptors.

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Dietary Intakes of Flavonols, Flavones and Isoflavones by Japanese Women and the Inverse Correlation between Quercetin Intake and Plasma LDL Cholesterol Concentration

Journal of Nutrition ◽

10.1093/jn/130.9.2243 ◽

2000 ◽

Vol 130 (9) ◽

pp. 2243-2250 ◽

Cited By ~ 446

Author(s):

Yusuke Arai ◽

Shaw Watanabe ◽

Mitsuru Kimira ◽

Kayoko Shimoi ◽

Rika Mochizuki ◽

...

Keyword(s):

Ldl Cholesterol ◽

Inverse Correlation ◽

Japanese Women ◽

Cholesterol Concentration ◽

Dietary Intakes

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Genotype-by-diet effects on co-variation in Lp-PLA2activity and LDL-cholesterol concentration in baboons fed an atherogenic diet

The Journal of Lipid Research ◽

10.1194/jlr.m800020-jlr200 ◽

2008 ◽

Vol 49 (6) ◽

pp. 1295-1302 ◽

Cited By ~ 11

Author(s):

Amanda Vinson ◽

Michael C. Mahaney ◽

Vince P. Diego ◽

Laura A. Cox ◽

Jeffrey Rogers ◽

...

Keyword(s):

Ldl Cholesterol ◽

Atherogenic Diet ◽

Cholesterol Concentration

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Cardiovascular risk factors and endothelial dysfunction

Clinical Science ◽

10.1042/cs20040078 ◽

2004 ◽

Vol 107 (6) ◽

pp. 609-615 ◽

Cited By ~ 20

Author(s):

Anthony S. WIERZBICKI ◽

Philip J. CHOWIENCZYK ◽

John R. COCKCROFT ◽

Sally E. BRETT ◽

Gerald F. WATTS ◽

...

Keyword(s):

Risk Factors ◽

Cardiovascular Risk ◽

Endothelial Dysfunction ◽

Ldl Cholesterol ◽

Disease Risk ◽

Absolute Risk ◽

Density Lipoprotein ◽

Cholesterol Concentration ◽

Individual Risk ◽

Multiple Risk Factor

Endothelial dysfunction is a feature of atherosclerosis and is associated with CHD (coronary heart disease) risk factors. This study aimed to determine the relationship between the degree of endothelial dysfunction and calculated cardiovascular risk. Endothelial function, as determined by the ACh/NP (acetycholine/sodium nitroprusside response) ratio on brachial plethysmography, was compared with cardiovascular risk as calculated from the Framingham, PROCAM (Prospective Cardiovascular Munster) and MRFIT (Multiple Risk Factor Intervention Trial) algorithms in 246 (187 male) patients, including 44 (22%) with established CHD. Endothelial dysfunction correlated with the total number of risk factors (r2=0.22; P=0.002) and was related to LDL (low-density lipoprotein)-cholesterol in men and triacylglycerols (triglycerides) in women. The ACh/NP ratio correlated with the occurrence of diabetes, CHD and the LDL-cholesterol concentration (r2=0.58; P<0.001). Endothelial dysfunction was associated with presence of CHD on receiver-operating characteristic plot analysis (area=0.706±0.04; P=0.001). There was no correlation between ACh/NP ratio and CHD risk calculated with the Framingham algorithm in men, although both ACh and NP response correlated separately with risk in women. The endothelial ACh/NP ratio correlated with absolute risk in the PROCAM algorithm (r2=0.41; P<0.005). Intermediate results were obtained with MRFIT. Individual risk factors make different contributions to endothelial dysfunction compared with their role in risk calculators. The stronger relationship of endothelial dysfunction with PROCAM risk reflects the contribution of male sex, LDL-cholesterol and triacylglycerols to risk calculated by this algorithm.

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