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J Viikari

Publications and source records attributed to J Viikari.

At least 19 recordsLinked to original sources
PubMed1992

Tracking of serum fatty acid composition: a 6-year follow-up study in Finnish youths.

The composition of fatty acids in serum cholesteryl esters was analyzed with gas chromatography in 759 Finnish boys and girls aged 3-18 years in 1980 and again in the same subjects in 1983 and in 1986. The mean percentage of linoleate (18:2 n-6) increased from 50.85% in 1980 to 52.60% in 1986, while there was a decrease in myristate (14:0), palmitate (16:0), and eicosapentaenoate (20:5 n-3). The percentage of oleate (18:1) did not change. The stability (tracking) of cholesteryl ester fatty acid composition was examined by calculating linear correlation coefficients among the percentages of each fatty acid at the three study points. For linoleate, 3- and 6-year tracking correlations were 0.59-0.61 and 0.50, respectively; they were of about the same magnitude for arachidonate (20:4 n-6) and lower for the other fatty acids. Results indicate that the serum cholesteryl ester fatty acid composition has somewhat lower tracking than the total cholesterol concentration. The changes in the mean fatty acid composition of the study population obviously reflect a shift from saturated to unsaturated dietary fats.

Adolescent↗
PubMed1992

Replacement of butter on bread by rapeseed oil and rapeseed oil-containing margarine: effects on plasma fatty acid composition and serum cholesterol.

The effects of zero-erucic acid rapeseed oil and rapeseed oil-containing margarine on plasma fatty acid composition and serum cholesterol were studied in butter users (n 43). Compliance to the substitution was followed by fatty acid analysis of total plasma and plasma phospholipids. The amount of substitute fats represented, on average, 21% of total fat and 8% of total energy intake. Changes in the relative fatty acid composition of plasma phospholipids indicated further fatty acid metabolism, and were closely related to the serum cholesterol level. The reduction in saturated fatty acids led to a significant increase in the proportion of n-3 and n-6 polyunsaturated fatty acids (PUFA) with the rapeseed oil diet, whereas the margarine caused a significant rise in n-6 PUFA only. The increase in the proportions of the two PUFA families occurred in accordance with their competitive order, most completely with the rapeseed oil diet. When butter was replaced by rapeseed oil, low-density-lipoprotein-cholesterol decreased by an average of 9.1% without a reduction in high-density-lipoprotein-cholesterol. During margarine substitution the reduction was 5.2%, on average. Of the plasma phospholipids, alpha-linolenic acid and the linoleic:stearic acid ratio, but not oleic acid, were the components most significantly correlated with serum cholesterol levels or the decrease in these levels. The results show that rapeseed oil can act primarily as a source of essential fatty acids, rather than that of monoenes, in the diet of butter users.

Adult↗
PubMed1979

High density lipoproteinemia due to vigorous physical work inhibits the incorporation of [3H]thymidine and the synthesis of glycosaminoglycans by human aortic smooth muscle cells in culture.

The effect of sera from normolipidemic men engaging in normal physical activity and from high density lipoproteinemic lumberjacks engaging in vigorous physical activity on the incorporation of [3H]thymidine and the synthesis of glycosaminoglycans by human aortic smooth muscle cells in culture was measured. At high concentration (15%) high density lipoproteinemic serum inhibited significantly (P less than 0.001) the incorporation of thymidine. The serum inhibited the synthesis of glycosaminoglycans at all concentrations tested (1--15%) with the most marked inhibition at 10 and 15%. At lower concentrations (1--5%) the inhibition was more pronounced for sulphated glycosaminoglycans than for hyaluronic acid. The inhibition was of the same magnitude for the subclasses (chondroitin, dermatan and heparan sulphates) of sulphated glycosaminoglycans studied. High density lipoproteinemia due to vigorous physical work is postulated as a protective factor against the early biochemical reactions of arterial smooth muscle cells in the development of atherosclerosis.

Adult↗
PubMed1979

Long-term effect of the combination of calcium clofibrate and calcium carbonate on serum total cholesterol, triglyceride and high density lipoprotein--cholesterol concentrations in hyperlipoproteinaemia. A comparative study with clofibrate.

Thirty hyperlipidaemic patients (19 with type IIA, 4 with IIB and 7 with type IV hyperlipoproteinaemia) were subjected to therapy with calcium clofibrate and calcium carbonate (4C, 2 + 2 g/day for 6 months) and the effect was compared with clofibrate (1C, 2 g/day) which was given for 6 months as well, in a single-blind placebo-controlled study. 4C and 1C decreased total serum cholesterol levels especially in subgroups IIA and IIB. 4C was somewhat more effective than 1C in decreasing (VLDL + LDL)-cholesterol in subgroup IIA. The HDL-cholesterol concentrations and the ratio of HDL-cholesterol and total cholesterol increased during treatment with both 1C and 4C. The HDL-cholesterol increase (vs. placebo) was 18%. The concentrations of serum triglycerides decreased by 33% during both treatment periods and there was no significant difference between 1C and 4C.

Adult↗
PubMed1979

Long-term effect of sotalol on plasma lipids.

1. We studied the effect on plasma lipids of sotalol given orally over a 12 month period to patients with essentially hypertension. 2. Plasma free fatty acid concentration was lower than initially at 1, 3, 6 and 12 months. The difference was significant (P less than 0.01) at 1 and 3 months. 3. Plasma cholesterol (VLDL + LDL-cholesterol) increased during treatment. Plasma total cholesterol increased from 5.49 +/- SD 0.94 mmol/l at the beginning to 6.37 +/- 1.10 mmol/l at 12 months (P less than 0.01). 4. HDL-cholesterol concentration and the ratio of HDL-cholesterol to total cholesterol decreased significantly. The ratios were 0.28 and 0.18 at the beginning and at 12 months respectively (P less than 0.001). 5. Plasma triglycerides increased simultaneously from 1.14 +/- 0.31 to 1.89 +/- 0.99 mmol/l (P less than 0.01).

Adult↗
PubMed1979

Meal induced increase in serum triglycerides has no effect on lymphocyte response to mitogens.

The effect of a standardized heavy meal on the lymphocyte transformations induced by phytohaemagglutinin (PHA), concanavalin A (Con A) and PPD tuberculin was studied. The meal significantly increased the serum triglycerides (P less than 0.01), while it had no effect on cholesterol or high density lipoprotein-cholesterol levels. The increase in serum triglycerides did not affect lymphocyte transformation induced by phytohaemagglutinin or concanavalin A in whole blood microcultures. A slight decrease was observed when lymphocytes were stimulated with one out of three concentrations of PPD tuberculin (P less than 0.05). However, there was no correlation with the increase of triglycerides and decrease in lymphocyte transformation. Our observation shows that physiological changes in serum triglycerides do not affect the capacity of lymphocytes to respond to mitogenic stimulation, and the whole blood micromethod for lymphocyte stimulation to screen the capacity of cell-mediated immunity does not depend on the meal schedule of the patients.

Adult↗
PubMed1979

Rapid increase of glycosaminoglycans in the aorta of hypercholesterolemic rats; a negative correlation with plasma HDL concentration.

Rats were kept either on a standard laboratory diet or a high cholesterol, olive oil diet for periods ranging from 1 day to 22 weeks. The effect of the high cholesterol, olive oil diet on the concentrations of cholesterol, glycosaminoglycans (GAGs) and collagen in aortic intima-media, were studied and the developing hyperlipidemia was characterized. The concentration of cholesterol in rat aorta was increased after 22 weeks' high cholesterol, olive oil diet, while collagen concentration was not affected. On the contrary, the concentration of aortic sulphated GAGs was significantly increased already after one week's high cholesterol, olive oil diet. The diet increased the formation of a cholesterol-rich very low density lipoprotein (VLDL), decreased high density lipoprotein (HDL)-associated cholesterol and phospholipids, but had virtually no effect on low density lipoprotein (LDL)-lipids. The concentrations of VLDL-cholesterol and -phospholipids showed positive correlations with the concentration of aortic GAGs (r = 0.89 and 0.83, respectively, P less than 0.05 for both). Stronger (negative) correlations were found between aortic GAGs and HDL-cholesterol and -phospholipids (r = 0.94 for both, P less than 0.01) suggesting that HDL may have a role in the control of arterial sulphated GAG concentration.

Animals↗
PubMed1979

Effect of sera from hyperlipidemic subjects and high-density lipoproteinemic runners on the synthesis of DNA and glycosaminoglycans by cultured human aortic smooth muscle cells.

Effects of hyperlipidemic, normolipidemic and high-density-lipoproteinemic (HD lipoproteinemic) sera from active runners were studied on cultured human aortic smooth muscle cells. The synthesis of DNA, hyaluronic acid and sulphated glycosaminoglycans (GAGs) in the presence of the various sera was measured by the incorporation of [3H]-thymidine and [3H]-glucosamine. The HD lipoproteinemic sera from runners stimulated the synthesis of DNA and sulphated GAGs less than normolipidemic and hyperlipidemic sera. The hyperlipidemic sera stimulated the synthesis of DNA slightly more than the other sera, but only after a 24 h preincubation. Accordingly, the concentration of HDL-cholesterol in serum was negatively correlated with the synthesis of DNA (r = -0.77, P less than 0.01) and sulphated glycosaminoglycans (r = -0.81, P less than 0.01). The sulphated GAGs/hyaluronate ratio was smaller in the presence of HD lipoproteinemic serum as compared with the other sera. The proliferation of aortic smooth muscle cells and the rate at which they synthesize sulphated GAGs have been considered important during the initiation of atherosclerosis in vivo. The present results suggest that sera having differences in the relative amounts of various lipoprotein fractions differ significantly in their influence on both of these arterial smooth muscle cell functions in vitro.

Aorta↗
PubMed1979

Plasma lipids on chronic uraemic and transplantation patients.

We studied the concentrations of total cholesterol, HDL-cholesterol and triglyceride in the plasma in renal (n = 48) patients. In undialyzed uraemic patients (mean serum creatinine value 439 mumol/l) the plasma cholesterol level was somewhat higher (6.47 mmol/l) than in the control (n = 27) group (5.67 mmol/l). HCL-cholesterol was lower (1.02 mmol/l vs 1.49 mmol/l) and the triglycerides higher (2.07 mmol/l vs 1.07 mmol/l) than in the control group. In dialyzed patients the cholesterol level (5.88 mmol/l) was lower but the triglyceride level higher (2.58 mmol/l) than in undialyzed patients. Renal transplantation corrected the lipid variables to a certain degree (plasma cholesterol 5.55 mmol/l, plasma HDL-cholesterol 1.27 mmol/1 plasma triglycerides 1.15 mmol/l) but HDL-cholesterol remained still somewhat lower than in the control group. No "critical level" of renal function at which the changes of lipoprotein metabolism arise, could be demonstrated, and it seems that e.g. HDL-cholesterol is low already when the diagnosis of renal insufficiency is made.

Adolescent↗
PubMed1978

Serum triglycerides and cholesterol and serum high-density lipoprotein cholesterol in highly physically active men.

The influence of extensive physical activity upon plasma lipids, in particular HDL cholesterol, was investigated. The material consisted of 23 regularly training men (mean age 44 years, average exercise 83 km running or skiing weekly), 15 healthy men (mean age 47 years), 10 young men (mean age 22 years), 12 healthy women (mean age 32 years) and 18 hyperlipidaemic patients. The exercise increased serum HDL cholesterol and FFA concentrations and decreased triglyceride levels significantly, but had no significant effect upon serum cholesterol concentration. There was a positive correlation between the amount of weekly exercise in km and plasma HDL cholesterol concentration. Exercising more than 70 km/week increased plasma HDL concentration clearly above the normal level. The advantages of an increase in plasma HDL cholesterol are discussed.

Adult↗
PubMed1978

Elevation of high-density lipoprotein in epileptic patients treated with phenytoin.

Previous observations have shown that serum alpha (high-density) lipoprotein (HDL) cholesterol is increased by some agents which also act as liver microsomal inducers. Against this background we measured the serum HDL and other lipoprotein and apolipoprotein A levels in 28 epileptic patients who received phenytoin as the only medication. In comparison with healthy controls of similar age and sex, the phenytoin users had significantly higher HDL cholesterol (p less than 0.001) and apolipoprotein A-I (p less than 0.01) levels. Highest values of both parameters were found in patients whose serum phenytoin concentration was within the therapeutic range. HDL cholesterol levels were above the control mean +2 S.D. in 43% of the phenytoin users. Hypertriglyceridemia was more common among male phenytoin users than in control males (33 vs. 16%). It is suggested that phenytoin increases the secretion of nascent HDL particles (and probably also that of VLDL) by the liver and that this could be associated with the induction of hepatic microsomes. Since HDL is inversely reversely related to risk of coronary heart disease, the observed increase of this lipoprotein may be an example of a beneficial side-effect of a drug.

Adult↗
PubMed1978

The effect of vigorous physical activity at work on serum lipids with a special reference to serum high-density lipoprotein cholesterol.

Serum lipid concentrations of lumberjacks whose occupational physical activity is most vigorous were compared with those of electricians. The lumberjacks had significantly higher serum HDL-cholesterol and significantly lower triglyceride and free fatty acid concentrations but there were no significant differences in total cholesterol levels. The favourable effect of vigorous physical activity at work on lipid metabolism is, however, epidemiologically not seen, obviously due to negative risk factors in lumberjacks' life.

Adult↗