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H O Bang

Publications and source records attributed to H O Bang.

At least 19 recordsLinked to original sources

[Radon].

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Denmark

Haemostatic function and platelet polyunsaturated fatty acids in Eskimos.

Death from cardiovascular disease is rare among Eskimos. Haemostasis was investigated in twenty-one Greeland Eskimos and twenty-one age and sex matched Danish controls. Platelet lipid analysis demonstrated that a high consumption of omega-3 polyunsaturated fatty acids (such as cis 5, 8, 11, 14, 17-eicosapentaenoic acid [C20:5]) by Eskimos increased the proportion of omega-3 polyunsaturated fatty acids in the platelets. The Eskimos had a significantly longer bleeding-time due to a reduction in platelet aggregation. It is suggested that C20:5 in the platelets is converted by the vascular-wall tissue to an anti-aggregatory prostacyclin. Partial dietary substitution of arachidonic acid by eicosapentaenoic acid may reduce the incidence of thrombotic disorders, including myocardial infarction.

Adult

Lipid metabolism, atherogenesis, and haemostasis in Eskimos: the role of the prostaglandin-3 family.

In Eskimos coronary heart disease is a rarity. This can partly be explained by their favorable plasma lipid levels. An additional factor seems, however, to be that in Eskimo food polyunsaturated fatty acids of the omega-3 series replace those of the omega-6 series. C20:5, omega-3 can be converted by the vessel wall to an antiaggregatory substance, whereas it has no proaggregatory effect on platelets. Consistent with these findings Eskimos were found to have a nearly 2-fold longer bleeding time than Danes. Platelet aggregability, too, was markedly depressed when exposing platelets from Eskimos to ADP and collagen.

Adenosine Diphosphate

Eicosapentaenoic acid and prevention of thrombosis and atherosclerosis?

Unlike arachidonic acid (eicosatetraenoic acid, C20:4omega-6, A.A.), eicosapentaenoic acid (C20:5omega-3, E.P.A.) does not induce platelet aggregation in human platelet-rich plasma (P.R.P.), probably because of the formation of thromboxane A3 (T.X.A3) which does not have platelet aggregating properties. Moreover, E.P.A., like A.A., can be utilised by the vessel wall to make an anti-aggregating substance, probably a delta17-prostacyclin (P.G.I3). This finding suggests that, in vivo, high levels of E.P.A. and low levels of A.A. could lead to an antithrombotic state in which an active P.G.I3 and a non-active T.X.A3 are formed. Eskimos have high levels of E.P.A. and low levels of A.A. and they also have a low incidence of myocardial infarction and a tendency to bleed. It is possible that dietary enrichment with E.P.A. will protect against thrombosis.

Arachidonic Acids

Clofibrate in type II hyperlipoproteinemia.

As a part of a double-blind randomized study, the safety and the lipid- and uric acid-lowering effect of clofibrate have been evaluated in 28 patients with type II hyperlipoproteinemia (HLP). A highly significant reduction of serum cholesterol occurred in type IIa and of serum triglyceride and choelsterol in type IIb HLP throughout the 60-week observation period (p less than 0.01). Of the patients with types IIa and IIb HLP, 65% had at least a 25% reduction of serum cholesterol. Uric acid was significantly reduced only during the first period of treatment (p less than 0.05). In the laboratory measurements concerning safety, a persistent, slight reduction was observed in Hb, hematocrit and alkaline phosphatase. No significant clinical side-effects were noted. Clofibrate is considered effective as a lipid-lowering agent in many cases of type II HLP.

Adult

The composition of food consumed by Greenland Eskimos.

Food specimens have been collected, by means of the double-portion technique, from Greenland Eskimo hunters and their wives, in all seven persons, on seven consecutive days. Their food was found to contain more protein and less carbohydrates than average Danish food and an almost equal amount of fat. Compared with Danish food, the fatty acid pattern of the consumed lipids--essentially of mammalian marine origin--showed a higher content of long chain polyunsaturated fatty acids (especially C20:5) and lower contents of linoleic and linolenic acids. However, the sum of the polyunsaturated fatty acids was smaller than in Danish food. Using Keys' formula, describing the serum cholesterol level as a function of the nutritional fatty acids, the essentially lower serum choelsterol level found in Greenland Eskimos was not explained by our findings. It is suggested instead to be a special metabolic effect of the long chain polyunsaturated fatty acids from marine mammals. There might be a similar effect on the plasma triglyceride and very low density lipoprotein concentrations, explaining the much lower plasma concentrations of these components in Eskimos than in Western populations. Our findings might have an essential bearing on the difference in morbidity from coronary atherosclerotic disease between these populations.

Adult