Variation in human blood high-density lipoprotein response to oral vitamin E megadosage.

In a preliminary attempt to distinguish random intrinsic and methodologic variations of blood lipid levels from any that have possibly been induced by ingestion of vitamin E, blood samples were analyzed in duplicate for lipids several times before and during oral vitamin E administration. Three of eight subjects showed temporally closely coordinated and maintained increases of high-density lipoprotein cholesterol and apolipoprotein-A, total apolipoprotein-A, and the ratio of high-density to low-density cholesterols. Changes of other lipids in these three subjects, and lipid changes in the other subjects, were much less dramatic, fell within the range of intrinsic random variation or statistical uncertainty, and showed no significant trends. The results suggest that elevation of high-density lipoproteins in response to ingestion of megadoses of vitamin E is very much an individual characteristic and not uniformly typical of the population at large. The findings complement published examples of individual variation of response to vitamin E as an explanation of disagreements between other reports.

Giant cell inflammation compared with amyloidosis of the internal elastic lamina in temporal arteries.

Close examination of a series of temporal artery biopsy specimens provided histologic and statistical evidence that any association between the occurrence of giant cell arteritis and senile amyloidosis of the temporal artery internal elastic lamina is not direct, but is associated incidentally with old age. Substantial demographic differences between the 2 conditions were found; the prevalence of giant cell arteritis first waxed and then waned with increasing age, while rates for senile amyloidosis of the temporal artery progressed steadily toward 100% in the ninth decade of life.

Variation of HDL cholesterol values in old age from around the world.

Reports of HDL cholesterol levels in the elderly from around the world show differences which could represent national or ethnic characteristics. However, statistical analysis reveals that such variations are hardly distinguishable from those generated by a group of independent laboratories in a single country. The differences in the international values may thus reflect only methodological variation, and thus be misleading if employed to relate HDLC levels to atherosclerotic complications in old age. Use of a common standard around the world could help resolve this uncertainty and provide a more reliable basis for study of the effects of race and culture upon HDLC in older people.

Acute changes in high-density lipoprotein cholesterol with exercise of different intensities.

The purpose of this study was to investigate the acute effects of exercise on plasma high-density lipoprotein cholesterol (HDL-C) and to determine whether the magnitude of this response would be affected by the intensity of the exercise. Twelve men (19-41 yr) ran an equivalent distance (9-12 km) on a treadmill on two separate occasions. On one occasion the exercise was performed at a speed that elicited 60% of the subject's maximal O2 uptake (VO2max), and on the other occasion exercise was performed at a speed that elicited 90% of VO2max. Changes in total cholesterol, triglycerides (TG), HDL-C, HDL apoprotein A (HDL-A), HDL saturation, lactate (LA), and free fatty acids (FFA) were measured during the course of each run, and all values were corrected for changes in plasma volume as indicated by hematocrit. There were significant increases (P less than 0.01) in HDL-C, HDL-A, and HDL saturation with exercise at both intensities, but greater increases in HDL-C (25 vs. 14%) and HDL-A (18 vs. 8%) were observed with the higher intensity exercise. Plasma FFA and TG did not differ between conditions, but LA concentrations rose significantly during the high-intensity exercise. These results indicate that increases in HDL components can occur with a relatively moderate exercise session and that the magnitude of these increases are directly related to the exercise intensity.

High-density lipoprotein cholesterol in differential diagnosis of senile dementia.

Levels of high-density lipoprotein cholesterol were found to be significantly lower in 5 men with multi-infarct dementia than in 12 men with senile dementia of the Alzheimer type. The large difference between the groups suggests that levels of high-density lipoprotein cholesterol may be useful in differential diagnosis of these two kinds of senile dementia. The finding also supports the theory that multi-infarct dementia may be a complication of atherosclerosis.

Occurrence of lipoprotein-X associated with intravenous administration of lipid emulsion in adults.

The intravenous lipid emulsion, Intralipid, both in vivo and in vitro causes a false-positive lipoprotein-X (LP-X) by immunoelectrophoresis and the electrophoresis-polyanion precipitation (EPAP) technic. The in vivo phenomenon has been shown to occur in adults, previously reported only in neonates. The false-positive LP-X may persist in the blood stream for some time following cessation of administration of the "Intralipid". This phenomenon should be taken into consideration when interpreting results of LP-X tests by these technics. It also has been shown that the presence of apolipoprotein-C is not necessary for LP-X like cathodal mobility and precipitation by the EPAP technic of complexes of albumin and Intralipid.

The eosinophilic fasciitis syndrome after phenytoin (dilantin) therapy.

A young woman with idiopathic temporal lobe epilepsy developed biopsy-proven oesinophilic fasciitis 16 months after the initiation of phenytoin therapy. Six months after withdrawal of this medication the fasciitis disappeared, and after 5 yr it has not recurred. This case highlights a possible association between the development of oesinophilic fasciitis and the use of medications such as phenytoin.

Dye induced alterations in lipoproteins and other plasma proteins.

A serendipitous observation that pre-staining of serum with bromo-phenol blue caused marked alteration of the immunoelectrophoretic features of alpha-1 lipoprotein led to examination of the effect of a series of dyes upon this and other serum proteins. Up to the present, eight effects have been distinguished. Five represent different forms of electrophoretic mobility changes, while the others are alterations in, respectively, immuno-precipitin activity, sedimentation characteristics, and diffusion behaviour in aqueous gels. The eight effects vary independently among different dyes for any one protein, as well as among different serum proteins for the same dye. The findings suggest the existence of multiple mechanisms of binding of dyes to proteins, and that pre-staining may provide assistance in a range of different partition procedures involving plasma proteins.