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A Aro

Publications and source records attributed to A Aro.

At least 55 records · Page 3Linked to original sources

Lack of effect on blood pressure by low fat diets with different fatty acid compositions.

We compared the effects on blood pressure (BP) of three isocaloric diets with reduced total fat and saturated fatty acid (SAFA) contents but with different proportions of monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). Diet LF (low fat) provided 20 en% fat (7.9% SAFA, 7.8% MUFA, 3.0% PUFA); diet HP (high PUFA) 26 en% fat (7.5% SAFA, 8.2% MUFA, 8.1% PUFA), and diet HM (high MUFA) 26 en% fat (7.3% SAFA, 14.1% MUFA, 3.2% PUFA). The diets were consumed for 8 weeks (intervention) preceded by 2 weeks and followed by 8 weeks on a habitual diet (baseline/ switchback) with 33-34 en% fat (13-14% SAFA, 12% MUFA, 6% PUFA). Forty-five free-living couples were randomly allocated into the three diet groups, and 43 men and 44 women completed the study. BP was measured weekly with an automatic device. Compliance to diet was monitored by repeated food records, serum fatty acid compositions, and weekly visits to a nutritionist. Both systolic BP (SBP) and diastolic BP (DBP) remained unchanged throughout the study in all three groups. The weight-adjusted mean (s.e.m.) BP values showed changes in SBP of +1.7 (1.8), -0.4 (1.7), and +1.9 (1.9) mm Hg on the LF, HP, and HM diets, respectively (difference NS), and DBP of +0.1 (1.0), +0.6 (1.0), and -0.3 (1.0) mm Hg, respectively (difference NS) between the last 2 weeks of the baseline and intervention periods. The expected fatty acid intakes were achieved, and there were no between-group differences in change of body weight, intake of dietary fibre and potassium, and 24-h sodium excretion. A reduction in total fat and SAFA intake and changes in the proportions of dietary MUFA and PUFA did not affect the BP levels of this normotensive population with an adequate intake of PUFA at baseline.

Adult↗

Effects of reduced-fat diets with different fatty acid compositions on serum lipoprotein lipids and apolipoproteins.

OBJECTIVE: To compare the effects on serum lipoproteins of three isocaloric diets with reduced total fat and saturated fatty acid (SFA) contents but with different proportions of monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). DESIGN: A low-fat diet (LF) provided 20 en% fat, 7.9% SFA, 7.8% MUFA, 3.0% PUFA; a high-PUFA diet (HP) 26 en% fat, 7.5% SFA, 8.2% MUFA, 8.1% PUFA; and a high-MUFA diet (HM) 26 en% fat, 7.3% SFA, 14.1% MUFA, 3.2% PUFA. Diets were consumed for 8 weeks in a parallel design, after 2 weeks on a habitual diet with 33-34 en% fat, 13-14% SFA, 12% MUFA, 6% PUFA, and followed by an 8-week period on habitual diet. Compliance to diet was monitored by repeated food records and weekly visits to a nutritionist. SUBJECTS: 45 free-living, middle-aged couples who were randomly allocated into the three diet groups; 43 men and 44 women completed the study. RESULTS: During the diet periods, a small but significant reduction in body weight of 0.4-1.0 kg was observed in all groups. Similar and significant reductions of mean weight-adjusted serum total cholesterol (4-8%), low-density lipoprotein (LDL) cholesterol (7-11%), and high-density lipoprotein (HDL) cholesterol (8-11%) were observed during the diets. HDL2-cholesterol and apoprotein (apo) A-I levels were reduced whereas HDL3-cholesterol and apoA-II increased. ApoB was significantly decreased during the HM diet only. Serum triglycerides increased significantly during diets LF (25%, P < 0.01) and HP (19%, P < 0.05) but not during diet HM (5%, NS). CONCLUSIONS: Reduction in the intake of total fat and saturated fatty acids reduced serum LDL-cholesterol and HDL2-cholesterol concentrations irrespective of the relative proportions of MUFA and PUFA in the diets. The results suggest that there might be some advantage in increasing the proportion of MUFA in low-fat diets, since the HM diet rich in MUFA reduced apoB and slightly attenuated the increase in serum triglycerides that is commonly associated with dietary fat reduction.

Adult↗

Large number of CD19+/CD23+ B cells and small number of CD8+ T cells as early markers for cow's milk allergy (CMA).

Assessment of activation of immune mechanisms is valuable in the early diagnosis of cow's milk allergy (CMA). The purpose of this study was to evaluate peripheral blood lymphocyte subclasses in children suspected of having CMA and healthy infants in order to detect an early marker for food allergy. Altogether 47 breast-fed infants, aged from 0.4 to 10 months were followed-up prospectively from birth because of atopic heredity. Twenty-three of the infants were healthy and 24 infants had a strong suspicion of and later challenge-proven cow's milk allergy. Leucocyte subsets were determined from peripheral blood mononuclear cells by flow cytometry. In response to a clinical cow's milk challenge, seven infants developed urticaria, 11 infants had eczema, three patients had loose stools, diarrhoea or vomiting and three infants had eczema and diarrhoea, loose stools or vomiting. The total percentage of B cells and also the proportion of B cells bearing a low-affinity IgE receptor as a marker for activation were significantly higher, whereas the percentage of CD8+ T cells was significantly lower in infants with challenge-proven CMA than in healthy controls. These results imply that infants with active CMA have a defect in regulation of B-cell function. Further, they suggest that imbalance of the ratio of suppressor and helper T cells might be an important factor in the etiopathogenesis of CMA. Our results show that large numbers of activated CD19+ B cells and low numbers of CD8+ T cells could be considered as early markers for food allergy since they are already detectable in peripheral blood during the earliest symptoms of CMA.

Antigens, CD19↗

Similar effects of diets rich in stearic acid or trans-fatty acids on platelet function and endothelial prostacyclin production in humans.

The effects of stearic acid (C18:0) and trans-fatty acids (trans-FAs) on measures of platelet function and prostacyclin (PGI2) production are poorly understood in humans. In this controlled dietary study, platelet function and endothelial PGI2 production were studied in healthy humans after they consumed diets rich in C18:0 or trans-FAs. For 5 weeks, 80 subjects consumed a baseline diet high in saturated FAs and were then switched to a diet containing 9.3% of energy as stearic acid or a diet containing 8.7 energy% as trans-FAs from hydrogenated vegetable oils for another 5 weeks. All diets contained 32.2 to 33.9 energy% fat, 14.6 to 15.8 energy% saturated plus trans-FAs, 12.2 to 12.5 energy% cis-monounsaturated, and 2.9 to 3.5 energy% polyunsaturated FAs. No significant differences between the C18:0 and trans-FA diets were found in the urinary excretion of 2,3-dinor-thromboxane B2 or 2,3-dinor-6-keto-prostaglandin F1alpha. In vitro production of thromboxane B2 by platelets as well as urinary excretion of beta-thromboglobulin were also similar after both diets. Collagen-induced in vitro aggregation was significantly enhanced after the C18:0 diet compared with the trans-FA diet (P=.02), whereas no differences between the diets were found with ADP. The results indicate similar effects of C18:0 and trans-FA diets on platelet activation and endothelial PGI2 production.

Adult↗

Association between toenail selenium and risk of acute myocardial infarction in European men. The EURAMIC Study. European Antioxidant Myocardial Infarction and Breast Cancer.

The association between selenium status and risk of acute myocardial infarction was examined in a multicenter case-control study in 10 centers from Europe and Israel in 1991-1992. Selenium in toenails was assessed for 683 nonfatal male cases with first acute myocardial infarction and 729 controls less than 70 years of age. Median toenail selenium content was 0.553 microgram/g for cases and 0.590 microgram/g for controls. After adjustment for age, center, and smoking, the odds ratio for myocardial infarction in the highest quintile of selenium as compared with the lowest was 0.63 (95 percent confidence interval 0.37-1.07, p for trend = 0.08). The observed inverse trend was somewhat stronger when the authors adjusted for vitamin E status (p = 0.05). Analysis stratified for smoking habits showed an inverse association in former smokers (odds ratio for the 75th-25th percentile contrast = 0.63 (95 percent confidence interval 0.43-0.94)), but not in current smokers (odds ratio = 0.97 (0.71-1.32)) or in those who had never smoked (odds ratio = 1.55 (0.87-2.76)). Analysis stratified by center showed a significant inverse association between selenium levels and risk of myocardial infarction for Germany (Berlin) only (75th to 25th percentile odds ratio = 0.62 (95 percent confidence interval 0.42-0.91)), which was the center with the lowest selenium levels. It appears that the increased risk of acute myocardial infarction at low levels of selenium intake is largely explained by cigarette smoking; selenium status does not appear to be an important determinant of risk of myocardial infarction at the levels observed in a large part of Europe.

Case-Control Studies↗

Influence of apolipoprotein A-1 promoter polymorphism on lipid levels and responses to dietary change in Finnish adults.

OBJECTIVES: To analyse the association between the G/A polymorphism in the apolipoprotein A-1 (apo A-1) promoter region and plasma lipid levels, as well as their responses to dietary change, in Finnish adults. SUBJECTS AND DESIGN: Blood samples from 86 subjects (42 men. 44 women) who attended a dietary intervention study carried out in North Karelia in 1993 were available for the current analysis. The diet study consisted of a 2-week baseline period, followed by an 8-week intervention period, and an 8-week switchback period. INTERVENTION: Diet was modified to a low-fat, low-cholesterol diet during the dietary intervention. MAIN OUTCOME MEASURES: Fasting plasma lipid, lipoprotein and apoliprotein levels were determined. RESULTS: At baseline, the high-density lipoprotein (HDL) cholesterol and apo A-1 levels were higher (P < 0.01) and the triglyceride levels were lower (P < 0.05) in men, but not in women, with the A allele. The differences in HDL cholesterol and apo A-1 levels between genotypes remained during the lowfat, low-cholesterol diet and switchback periods. Apart from the difference between responses in apo A-1 during switchback to the original diet, lipid responses to dietary change did not differ significantly between genotypes. CONCLUSION: Our findings indicate a significant association between the apo A-1 promoter polymorphism and plasma apo A-1 and HDL-cholesterol in men. In theory, the higher plasma HDL-cholesterol and apo A-1 levels in the GA/AA group may confer some protection against coronary artery disease. The differences in HDL-cholesterol and apo A-1 levels between genotypes persisted during different diets suggesting that the possible benefit is independent of fat and cholesterol intake.

Adult↗

Stearic acid, trans fatty acids, and dairy fat: effects on serum and lipoprotein lipids, apolipoproteins, lipoprotein(a), and lipid transfer proteins in healthy subjects.

To compare the effects on serum lipoproteins of stearic acid, trans fatty acids, and dairy fat, 80 healthy subjects consumed a dairy fat-based (baseline) diet for 5 wk, then an experimental diet high in either trans fatty acids (8.7% of energy; n = 40) or stearic acid (9.3% of energy; n = 40) for another 5 wk. All diets provided 32.2-33.9% of energy as fat, 14.6-15.8% as saturated plus trans fatty acids, 11.4-12.5% as cis-monounsaturated fatty acids, 2.9-3.5% as polyunsaturated fatty acids, and 200-221 mg cholesterol/10 MJ. Compared with the dairy fat diet, stearic acid and trans fatty acids decreased serum total cholesterol concentrations similarly (by 13% and 12%, respectively, P < 0.001) but the trans fatty acid diet decreased HDL cholesterol (17%) and apolipoprotein (apo) A-I (15%) significantly more than did the stearic acid diet (11% and 12%, respectively). Stearic acid but not trans fatty acids reduced concentrations of LDL cholesterol and apo B significantly (P < 0.001). The trans fatty acid diet increased the ratio of LDL to HDL cholesterol (19%) and of apo B to apo A-I (16%) more than did the dairy fat diet (P < 0.001) but the stearic acid diet had no effect. Lipoprotein(a) concentrations increased with both experimental diets, significantly more with trans fatty acids (30%) than with stearic acid (10%). In conclusion, high amounts of trans fatty acids had more adverse effects on lipoproteins than did equal amounts of stearic acid and dairy fat. Stearic acid reduced LDL cholesterol, did not affect the ratio of LDL to HDL cholesterol, and increased lipoprotein(a), although to a lesser extent than did trans fatty acids. Dietary fats low in both saturated fatty acids and trans fatty acids should be favored.

Adult↗

Effect of alpha-tocopherol (vitamin E) and beta-carotene supplementation on the incidence of intermittent claudication in male smokers.

We examined the primary preventive effect of vitamin E (alpha-tocopherol) and beta-carotene supplementation on intermittent claudication. The subjects--participants in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study--were male smokers aged 50 to 69 years who were randomly assigned to receive 50 mg of alpha-tocopherol daily, 20 mg of beta-carotene daily, both, or placebo. At baseline, there were 26 289 men with no history or symptoms of intermittent claudication. The Rose questionnaire on intermittent claudication was administered annually to discover incident cases. We observed 2704 cases of first occurrence of typical intermittent claudication during a median follow-up time of 4.0 years. Compared with placebo, the adjusted relative risk for typical intermittent claudication among those who received alpha-tocopherol only was 1.11 (95% confidence interval, 1.00-1.24); among those who received alpha-tocopherol and beta-carotene, 1.02 (0.91-1.13); and among those who received beta-carotene only, 1.02 (0.92-1.14). When we compared the alpha-tocopherol-supplemented subjects with those who received no alpha-tocopherol, the adjusted relative risk for typical intermittent claudication was 1.05 (0.98-1.14), and for beta-carotene-supplemented subjects compared with those who did not receive beta-carotene, the relative risk was 0.96 (0.89-1.04). In conclusion, no primary preventive effect on intermittent claudication was observed among middle-aged male smokers who were supplemented with alpha-tocopherol, beta-carotene, or both.

Antioxidants↗

Association of the fatty acid composition of serum phospholipids with hemostatic factors.

It has been suggested that the fatty acid composition of serum phospholipids is an independent risk factor for cardiovascular disease. We examined the association of the fatty acid composition of serum phospholipids with fibrinogen, factor VII antigen (FVII:Ag), factor VII coagulant activity (FVII:C), plasminogen, and lipoprotein(a) [Lp(a)] in 338 men and 363 women 45 to 64 years old. Palmitic acid, the most abundant saturated fatty acid, was positively associated in univariate analyses with plasminogen, which explained 5.2% of its variance among men (P<.0001) and 5.8% among women (P<.0001). Linoleic acid, which is the most abundant polyunsaturated fatty acid, was negatively associated with plasminogen and fibrinogen. This explained 1.1% of the variance in fibrinogen among men (P=.04) and 3.2% among women (P=.0006) and 4.1% of the variance in plasminogen in both sexes (P<.0001). Dihomogammalinolenic acid was positively associated with FVII:Ag and explained 3.7% of its variance among men (P=.0003) and 4.6% among women (P<.0001). Furthermore, dihomogammalinolenic acid was positively and significantly associated with FVII:C, fibrinogen, and plasminogen among women but not among men. All these associations remained significant after adjustment for multiple potential confounding factors such as age, smoking, serum lipids, and body mass index. In conclusion, our findings suggest that linoleic acid, palmitic acid, and dihomogammalinoleic acid are significant independent determinants of hemostatic profile. It is not clear, however, to what extent these results reflect the effects of fatty acids on coagulation and to what extent they reflect the activity of inflammatory processes in the arteries.

8,11,14-Eicosatrienoic Acid↗

In vivo bone lead measurement in suburban teenagers.

OBJECTIVE: Bone represents a biologically active long-term storage site for lead, and bone lead data on teenagers are limited. Therefore, this study was designed to identify the distribution of bone lead in a teenage population and to explore the environmental and demographic factors associated with bone lead concentrations in young, nonoccupationally exposed subjects. DESIGN: A cross-sectional study of bone lead levels in high school students. PARTICIPANTS: A total of 168 students at a suburban Boston high school. Subjects (90 boys, 78 girls) ranged in age from 13.5 to 19 years and included 40% nonwhite minorities. Of the 168 subjects, 45 lived in homes constructed before 1960. None of the participants reported a history of lead poisoning. OUTCOME MEASURES: Tibial bone lead concentrations were measured in vivo for 60 minutes using K x-ray fluorescence. Lead exposure information was obtained by self-administered questionnaire. RESULTS: Point estimates of bone lead levels ranged from -7.15 to 14.23 microg lead/g bone mineral (microg/g), (mean, 4.0 microg/g; standard deviation, 4.4 microg/g). The reported measurement uncertainties accompanying each of the point estimates ranged from 2.56 to 9.01 microg/g (mean, 3.9 microg/g; standard deviation, 1.0 microg/g). Bone lead levels were not associated with the demographic factors of age, sex, or race. Additionally, current home conditions (housing age, traffic level) were not predictive of bone lead levels, even though these factors were predictive of in-home lead concentrations. CONCLUSIONS: These results demonstrate that although bone lead levels are measurable in this age group, the common predictors of blood and bone lead concentrations are not explanatory for bone lead levels.

Adolescent↗

Decrease in birth weight in relation to maternal bone-lead burden.

OBJECTIVES: Birth weight predicts infant survival, growth, and development. Previous research suggests that low levels of fetal lead exposure, as estimated by umbilical cord blood-lead levels at birth, may have an adverse effect on birth weight. This report examines the relationship of lead levels in cord blood and maternal bone to birth weight. METHODS: Umbilical cord and maternal venous blood samples and anthropometric and sociodemographic data were obtained at delivery and 1-month postpartum. Blood-lead levels were analyzed by atomic absorption spectrophotometry. Maternal tibia and patella lead levels were determined at 1-month postpartum with use of a spot-source 109Cd K-X-ray fluorescence instrument. The relationship between birth weight and lead burden was evaluated by multiple regression with control of known determinants of size at birth. RESULTS: Data on all variables of interest were obtained for 272 mother-infant pairs. After adjustment for other determinants of birth weight, tibia lead was the only lead biomarker clearly related to birth weight. The decline in birth weight associated to increments in tibia lead was nonlinear and accelerated at the highest tibia lead quartile. In the upper quartile, neonates were on average, 156 grams lighter than those in the lowest quartile. Other significant birth weight predictors included maternal nutritional status, parity, education, gestational age, and smoking during pregnancy. CONCLUSIONS: Our results indicate that bone-lead burden is inversely related to birth weight. Taken together with other research indicating that lead can mobilize from bone into plasma without detectable changes in whole blood lead, these findings suggest that bone lead might be a better biomarker than blood lead. Because lead remains in bone for years to decades, mobilization of bone lead during pregnancy may pose a significant fetal exposure with health consequences, long after maternal external lead exposure has declined.

Birth Weight↗

Coagulation and fibrinolysis factors in healthy subjects consuming high stearic or trans fatty acid diets.

The effects of stearic acid (C18:0) and trans fatty acids on variables related to coagulation and fibrinolysis were studied in 80 healthy humans average age 29 +/- 9 years. All subjects consumed a baseline diet high in saturated fatty acids, mainly from dairy fat for 5 weeks. After this baseline diet they were allocated either to a diet high (8.7% of energy, En%) in trans fatty acids from partially hydrogenated vegetable oil (40 subjects) or a diet high (9.3 En%) in stearic acid (40 subjects) for 5 weeks. All diets contained 32.2-33.9 En% fat, 14.6-15.8 En% saturated plus trans fatty acids, 12.2-12.5 En% cis-monounsaturated and 2.9-3.5 En% polyunsaturated fatty acids and 216-250 mg/10 MJ cholesterol. The fats were mixed into solid foods and almost all daily food was provided. In comparison with the baseline dairy fat diet no change was observed in the concentrations of plasma fibrin degradation products and D-dimers. Also the factor VII coagulant activity (F VII:C), tissue type plasminogen activity (tPA) and plasminogen activator inhibitor activity (PAI-1) were not affected by the experimental diets. Small increase in plasma fibrinogen concentration during the stearic acid diet was statistically significant (from 3.49 to 3.63 g/l: p = 0.041), but probably without any biological significance. Both diets increased plasma level of lipoprotein Lp(a). It can be concluded that as far as coagulation and fibrinolysis are concerned there is no need to differentiate between stearic acid or trans monoenoic fatty acids.

Adult↗

The serum cholesterol ester fatty acid composition but not the serum concentration of alpha tocopherol predicts the development of myocardial infarction in 50-year-old men: 19 years follow-up.

A low serum tocopherol concentration and a low proportion of linoleic acid in plasma cholesterol esters have been reported to be associated with coronary heart disease. This study was undertaken to evaluate the predictive importance of the serum cholesterol ester fatty acid composition and serum tocopherol concentration in addition to established risk factors for myocardial infarction. The study comprised 2322 fifty-year-old men who participated in a health survey in 1970-1973 regarding risk factors for coronary heart disease. The proportions of myristic, palmitic, palmitoleic, and dihomogammalinolenic acid were significantly higher in 1970-1973 in subjects who suffered myocardial infarction during the following 19 years, while the proportion of linoleic acid was lower, than in those who remained healthy. Serum tocopherol did not differ significantly between the groups. LDL/HDL ratio, systolic blood pressure, and arachidonic acid/dihomogammalinolenic acid ratio were significant independent discriminators between cases and controls in a stepwise logistic regression analysis. This study suggests that middle-aged men who later develop a myocardial infarction are characterized not only by conventional risk factors but also by an altered fatty acid composition of serum cholesterol esters, with a low arachidonic to dihomogammalinolenic acid ratio, indicating reduced delta 5 desaturase activity. This may imply that changes in the quality of dietary fat intake, or an altered capacity to metabolize fatty acids in the body, could precede the development of coronary heart disease.

Biomarkers↗

Predictors of adipose tissue carotenoid and retinol levels in nine countries. The EURAMIC Study.

The adipose tissue carotenoid (alpha-carotene, beta-carotene, and lycopene) and retinol levels and their predictors were determined in 686 male and 339 female middle-aged and elderly subjects from eight European countries and Israel during the years 1991 to 1992. Adipose tissue carotenoid levels in men were 50-76% of those in women, whereas the retinol level in men was 116% of that in women (p < 0.001). When all significant predictors of antioxidant levels were considered in men, waist circumference was shown to be an independent predictor of adipose tissue alpha-carotene, age, waist circumference, and alcohol use were independent predictors of beta-carotene; age, body mass index, and waist circumference were predictors of lycopene; and waist circumference, smoking, and alcohol consumption were predictors of retinol. In the same way, in women waist circumference was shown to be an independent predictor of alpha-carotene level, BMI was a predictor of beta-carotene, smoking was a predictor of retinol, and alcohol consumption was a predictor of lycopene. The observed association of age with beta-carotene was positive, that with lycopene was inverse, and those of body mass index and waist circumference with the antioxidant levels were inverse. Alcohol use was inversely associated with beta-carotene level, and smoking and alcohol use were positively associated with retinol and lycopene levels. Epidemiologic studies on diet-disease relations using adipose tissue levels of carotenoids and retinol should consider gender, body size and composition, smoking, and alcohol consumption as potential confounders in diet-disease relations.

Adipose Tissue↗

Determinants of bone and blood lead levels among community-exposed middle-aged to elderly men. The normative aging study.

Levels of lead in bone serve as a dosimeter for cumulative exposure to lead; moreover, lead in bone may serve as an internal source of circulating lead many years after environmental exposure has ceased. The authors measured lead in blood and used a K-x-ray fluorescence instrument to measure lead in the tibia (cortical) and patella (trabecular) bones in a cross-sectional survey of 719 middle-aged to elderly male participants in the Normative Aging Study who were without unusual occupational exposures to lead and who were healthy when enrolled in 1962-1965. Blood lead levels ranged from < 1 to 27.9 micrograms/dl, with a geometric mean of 5.7 micrograms/dl. Tibia and patella lead level ranges (geometric means) were < 1-51 (20.8) micrograms/g and 3-77 (29.8) micrograms/g, respectively. In backwards elimination multivariate regression models that considered age, race, education, retirement status, measures of both current and cumulative smoking, and alcohol consumption, the factors that remained significantly related to higher levels of both tibia and patella lead were higher age and measures of cumulative smoking, and lower levels of education. In the final model predicting blood lead that began with these same covariates and also included tibia and patella lead, the factor that accounted for the dominant portion of the variance in blood lead was patella lead. After adjustment for measurement error, a rise in patella lead from the median of the lowest to the median of the highest quintiles (13-56 micrograms/g) corresponded to a rise in blood lead of 4.3 micrograms/dl. The authors conclude that bone lead levels are substantial and comprise the major source of circulating lead in these men.

Adult↗