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Biomedical subjects

E B Schmidt

Publications and source records attributed to E B Schmidt.

At least 55 records · Page 3Linked to original sources
PubMed1993

Hypolipidemic effects of nicotinic acid in patients with familial defective apolipoprotein B-100.

Familial defective apolipoprotein B-100 (FDB) is a dominantly inherited disorder associated with hypercholesterolemia, in which an amino acid substitution in apolipoprotein B-100 results in low-density lipoprotein (LDL) particles that bind poorly to the LDL receptor and accumulate in plasma. Patients with FDB described to date have been heterozygous for this disorder, and their plasma contains both normal and defective-binding LDL particles. We have evaluated the hypocholesterolemic effects of nicotinic acid (3 g/d) in four patients with FDB, and compared the response to that of nine patients with heterozygous familial hypercholesterolemia (FH). Concentrations of LDL decreased by 24% in patients with FDB and by 14% in patients with FH. These results support the view that drugs which reduce LDL synthesis may be particularly effective in the treatment of patients with FDB.

Adult↗
PubMed1993

The effect of low-dose supplementation with n-3 polyunsaturated fatty acids on some risk markers of coronary heart disease.

Epidemiological data have suggested that a low dose of dietary n-3 polyunsaturated fatty acids from seafood may protect against coronary heart disease. We studied the effect of supplementation with a low dose of very long-chain n-3 fatty acids (0.65 g day-1) on plasma lipids, haemostasis, and neutrophil aggregation. Twenty-four healthy subjects were randomized to supplementation with very long-chain n-3 fatty acids or a control oil for 8 weeks. Laboratory analyses were done twice before and twice at the end of the supplementation period. The supplement with n-3 polyunsaturated fatty acid did not significantly affect plasma lipids or plasma levels of fibrinogen, factor VII, plasminogen activator inhibitor, whole blood aggregation or aggregability of neutrophil leukocytes. Therefore, the potential beneficial effect of very long-chain n-3 fatty acids in coronary heart disease is likely to be mediated through other mechanisms.

Adult↗
PubMed1992

The acute effect of a single very high dose of N-3 fatty acids on coagulation and fibrinolysis.

The objective of the study was to investigate the acute effect of a single very high dose of n-3 PUFA on coagulation and fibrinolysis. Forty healthy volunteers were randomized into two groups to receive either 20 grams of n-3 PUFA or 20 grams of n-6 PUFA as a single dose at 6 p.m. with their evening meal. Coagulation and fibrinolysis were evaluated in the fasting state at 8 a.m. the next morning and compared to values obtained at 8 a.m. the day before, when the participants were on their habitual diets. PAI-1 activity in plasma increased by a mean of 62% in subjects randomized to receive n-3 PUFA despite that no changes could be demonstrated in t-PA antigen levels. PAI-1 activity was unaltered in the 20 controls receiving n-6 PUFA. Plasma fibrinogen, coagulation factor VII, thrombin-antithrombin complexes and D-dimer did not significantly change after either supplement. The substantial increase in levels of PAI-1 activity in plasma after a single very high dose of n-3 PUFA may limit the usefulness of single very high doses of n-3 PUFA in acute clinical conditions.

Adult↗
PubMed1992

Intravenous acetylsalicylic acid--dose-related effects on platelet function and fibrinolysis in healthy males.

Low-dose acetylsalicylic acid (ASA) has been shown to be beneficial in patients with acute myocardial infarction and unstable angina pectoris. Oral administration of ASA is difficult in the acute phase of these syndromes. In this study we evaluated the effect of 25 mg, 50 mg or 100 mg of ASA given as an intravenous bolus injection on platelet function and fibrinolysis in healthy males and related this to plasma concentrations of ASA. No adverse effects were found. A complete inhibition of serum thromboxane B2 synthesis was demonstrated 5 min after injection of 100 mg ASA intravenously. ASA disappeared from the circulation within 60 min after bolus injection and at this time thromboxane B2 synthesis was inhibited dose-dependently by 71%, 90% and 100% for doses of 25 mg, 50 mg and 100 mg, respectively. Inhibition of thromboxane B2 synthesis after 100 mg of intravenous ASA was still 96.5% at 24 h and 93.4% at 48 h after the injection. The bleeding time measured at 30 min after ASA administration was significantly prolonged on the average by 70 s, 144 s and 211 s after 25 mg, 50 mg and 100 mg of ASA, respectively. Minor, but significant changes were found in tissue plasminogen activator antigen and in plasminogen activator inhibitor within the first hour after injection of low dose ASA, but similar changes were found after injection of saline. No change in tissue plasminogen activator activity was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Differences in apolipoprotein (a) polymorphism in west Greenland Eskimos and Caucasian Danes.

Previous studies in Greenland suggest that death rates from ischemic heart disease [IHD] are lower in Eskimos than in Danes and other Caucasian populations. This has been explained by a high intake of n-3 polyunsaturated fatty acids with beneficial effects on blood lipids and hemostasis. In other populations, lipoprotein(a) [Lp(a)] is associated with IHD, plasma concentrations of Lp(a) being genetically determined to a major extent. We have compared Lp(a) concentrations and apo(a) phenotypes in 120 Greenlandic Eskimos with those in 466 Danish men. The median Lp(a) concentration in Eskimos (8.7 mg/dl;[95% CI 6.5-10.7]) was not significantly different from that in Danes (6.3 mg/dl; [95% CI 5.2-7.0]), whereas the 90th percentile was significantly higher among Danes: 46.36 mg/dl; [95% CI 43.0-54.3] vs. 27.6 mg/dl [95% CI 20.7-36.9]. In 20% of the Danes, but in only 8% of the Eskimos (P = 0.009), the concentration of Lp(a) exceeded 30 mg/dl. The difference is probably explained by a low frequency of the low molecular weight apo(a) phenotypes among Eskimos, since the apo(a) isoforms F and B were absent, and the S1 and S2 types were present in only 3.3% of Eskimos. In contrast, these apo(a) isoforms were present in 26.6% of the Danes in either single-band or double-band phenotypes. The pattern of apo(a) polymorphism found in this study could provide part of a genetic explanation for the putative low rates of IHD in Eskimo populations.

Adult↗
PubMed1992

The effects of dietary supplementation with n-3 polyunsaturated fatty acids in patients with rheumatoid arthritis: a randomized, double blind trial.

STUDY OBJECTIVE: To determine the effect of dietary supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA) on disease variables in patients with rheumatoid arthritis. DESIGN: Multicenter, randomized, placebo controlled, double blind. SETTING: Three Danish hospital Departments of Rheumatology. PATIENTS: Fifty-one patients with active rheumatoid arthritis. INTERVENTION: Random allocation to 12 weeks of treatment with either six n-3 PUFA capsules (3.6 g) or six capsules with fat composition as the average Danish diet. MAIN RESULTS: Significant improvement of morning stiffness and joint tenderness. No significant effect on the four other assessed clinical parameters. No serious side effects. CONCLUSIONS: Dietary supplementation with n-3 PUFA in patients with rheumatoid arthritis improved two out of six patient reported disease parameters. Further studies are needed to clarify the more precise role of n-3 PUFA in the treatment of rheumatoid arthritis.

Adult↗
PubMed1992

Normal lipoprotein(a) concentrations and apolipoprotein(a) isoforms in patients with insulin-dependent diabetes mellitus.

Lipoprotein(a) [Lp(a)] is an LDL particle in which apoliporotein B-100 is attached to a large plasminogen-like protein called apolipoprotein(a) [apo(a)]. Apo(a) has several genetically determined phenotypes differing in molecular weight, to which Lp(a) concentrations in plasma are inversely correlated, and plasma Lp(a) concentrations above 20-30 mg dl-1 are an independant risk factor for ischaemic heart disease (IHD). To investigate whether Lp(a) could be important for the high cardiovascular mortality rate in patients with insulin dependent diabetes mellitus (IDDM), we determined Lp(a) concentrations and phenotypes in a group of 108 men (median age 32 years) with IDDM without nephropathy. A group of 40-year-old men (n = 466) served as controls. The median Lp(a) concentration was 7.4 mg dl-1 [95% CI 4.9 to 11.7] in the diabetic patients and 6.3 mg dl-1 [95% CI 5.2 to 7.0] in controls. The Lp(a) concentration exceeded 30 mg dl-1 in 22% of IDDM patients and in 20% of controls (P = 0.13). Moreover, the distribution of apo(a) phenotypes did not differ between patients and control. Lp(a) levels and apo(a) phenotypes are thus apparently the same in IDDM patients without nephropathy and controls. These findings do not exclude the possibility that Lp(a) may be increased in patients with nephropathy in whom coronary artery disease frequently co-exist or that Lp(a) in a given concentration is more atherogenic in IDDM patients than in persons without IDDM.

Apolipoproteins↗
PubMed1992

n-3 polyunsaturated fatty acid supplementation (Pikasol) in men with moderate and severe hypertriglyceridaemia: a dose-response study.

The effect of n-3 fatty acids in 11 men with hypertriglyceridaemia was investigated. The subjects were given daily supplements with three different doses of n-3 fatty acids for 8-week periods. The supplements given were 2, 4 and 9 g of n-3 fatty acids/day, respectively. Total cholesterol, triglycerides and the ratio of total cholesterol to HDL-cholesterol significantly decreased with all three doses in a dose-dependent way. HDL-cholesterol increased in a dose-dependent fashion, while apolipoproteins A1 and B were unaltered by the supplements apart from a small increase in apolipoprotein A1 after the lowest dose of n-3 fatty acids. The greatest effect was observed after 2 g of n-3 fatty acids/day.

Adult↗
PubMed1992

Long-term supplementation with n-3 fatty acids, I: Effect on blood lipids, haemostasis and blood pressure.

The effect of dietary supplementation with 4 g of n-3 polyunsaturated fatty acids (PUFA) daily for 9 months on blood pressure, plasma lipids and lipoproteins, platelet function, coagulation and fibrinolysis was studied in 24 healthy volunteers. Each variable was determined before, after 6 weeks and 9 months of supplementation with n-3 PUFA, and 3 months after the supplementation period had ended. Systolic and diastolic blood pressure declined after intake of n-3 PUFAs. Plasma triglycerides were reduced, and there was a trend towards an increase in HDL-cholesterol after 9 months of supplementation, while total cholesterol, LDL-cholesterol and apolipoproteins A1 and B were unaltered. The bleeding time was increased, and plasma levels of von Willebrand factor decreased after 9 months supplementation with n-3 PUFA. Fibrinogen levels increased, while fibrinolysis was reduced after 9 months supplementation with n-3 PUFA. Overall, no clear benefit on lipid pattern and haemostasis was achieved with respect to development of coronary heart disease.

Adult↗
PubMed1992

Long-term supplementation with n-3 fatty acids, II: Effect on neutrophil and monocyte chemotaxis.

The effect of a daily supplement with 4 g of n-3 polyunsaturated fatty acids (PUFA) for 9 months to 24 healthy volunteers on neutrophil and monocyte chemotaxis was studied using the under-agarose technique. Autologous serum and n-formyl-methionyl-leucyl-phenylalanine were used as chemoattractants. The effect after 9 months of supplementation with n-3 PUFA was also compared to results after short-term supplementation with n-3 PUFA for 6 weeks. Monocyte chemotaxis was reduced after 9 months of supplementation with n-3 PUFA to the same extent as after 6 weeks supplement. Neutrophil-directed migration towards chemoattractants was reduced after 9 months on fish oil, and this decrease was significantly greater than the decrease obtained after 6 weeks of supplementation. The spontaneous migration of neutrophils was significantly attenuated after 9 months compared to baseline and to 6 weeks. These findings lend support to a role for n-3 PUFA in the management of chronic inflammatory and atherosclerotic vascular diseases.

Adult↗
PubMed1990

Dose-response studies on the effect of n-3 polyunsaturated fatty acids on lipids and haemostasis.

We have studied the dose-response effects of dietary supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA's) on lipids and haemostasis. Ten healthy males were each given 1.3 g, 4 g or 9 g of n-3 PUFA's daily for 6-week periods. Bleeding time, HDL-cholesterol and plasminogen activator inhibitor increased with the dose of n-3 PUFA. Plasma fibrinogen and triglyceride levels were reduced in a dose-dependent fashion. After ingestion of 1.3 g of n-3 PUFA's plasma fibrinogen decreased from 9 to 7 mumol/l and HDL-cholesterol increased from 1.2 to 1.3 mmol/l. The bleeding time was prolonged from 5 to 6.5 min while triglyceride levels decreased from 1.2 to 0.9 mmol/l after ingestion of 4 g of n-3 PUFA's. Dietary supplementation with the highest daily dose (9 g) reduced plasma levels of triglycerides, fibrinogen and von Willebrand factor, while bleeding time, plasminogen activator antigen, plasminogen activator inhibitor and the ratio of HDL-cholesterol to total cholesterol increased.

Adult↗
PubMed1990

The effect of n-3 polyunsaturated fatty acids on lipids, platelet function, coagulation, fibrinolysis and monocyte chemotaxis in patients with hypertension.

We have studied the effect of dietary supplementation with 4 g of n-3 polyunsaturated fatty acids (n-3 PUFA) daily for 6 wk on plasma lipids, haemostasis and monocyte chemotaxis in 10 patients with untreated hypertension. Total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides did not change, but the ratio of total to HDL-cholesterol was significantly reduced after the fish oil supplement. Platelet function was unaltered by intake of n-3. Plasma fibrinogen and fibronectin decreased after supplementation with n-3 PUFA, while the effects on fibrinolysis were equivocal. Monocyte chemotaxis was reduced by the supplement. These data lend support to a role for an increased intake of n-3 PUFA in the management of patients with hypertension.

Adult↗
PubMed1989

The effect of n-3 fatty acids on lipids and haemostasis in patients with type IIa and type IV hyperlipidaemia.

Plasma lipids and haemostasis were investigated in 17 patients with hyperlipidaemia before and after 6 weeks supplementation with 6 g n-3 fatty acids. Nine of the patients had type IIa and 8 had type IV hyperlipidaemia. No effect on plasma cholesterol, LDL- or HDL-cholesterol were seen, but plasma triglycerides decreased after n-3 supplementation. Apolipoprotein B increased and apolipoprotein A1 decreased after the oil supplement. The bleeding time was prolonged, but platelet aggregation was unaltered by n-3 fatty acids. Protein C activity increased in type IIa and decreased in type IV after the supplement. Fibrinolysis was markedly depressed while von Willebrand factor antigen was reduced after intake of n-3 fatty acids.

Adult↗
PubMed1989

n-3 fatty acids and cardiovascular disease--observations generated by studies in Greenland Eskimos.

Polyunsaturated fatty acids of the n-3 type (n-3 PUFAs) may offer some protection against ischaemic heart disease (IHD). Part of the evidence has been derived from our investigations on Greenland Eskimos. Through six expeditions to Greenland, we have studied Eskimos living on their traditional sea diet. We found favourable changes in lipids and lipoproteins, together with a reduced platelet reactivity in the Eskimos - findings of importance for their low incidence of IHD. In this survey we intend to review studies on the effects of an increased intake of n-3 PUFAs, focusing on lipids and platelets. We conclude that beneficial changes in general have been obtained. However, individual patients and patient groups likely to profit from supplementation with n-3 PUFAs need to be further defined. The optimum dose needs to be established, and the effect and safety to be documented by highly needed long term studies.

Coronary Disease↗