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A Aro

Publications and source records attributed to A Aro.

At least 73 records · Page 4Linked to original sources
PubMed1996

The effects of the apolipoprotein B signal peptide (ins/del) and XbaI polymorphisms on plasma lipid responses to dietary change.

There is interindividual variation in plasma lipid response to dietary changes. The polymorphisms which are associated with plasma lipid levels could possibly explain part of this variation. Therefore, the apolipoprotein B (apo B) signal peptide insertion/deletion (ins/del) and XbaI restriction fragment length polymorphisms are possible regulators of plasma lipid responses. We examined their role in the regulation of plasma lipid responses in 87 North Karelians (43 men, 44 women). The dietary study consisted of a 2-week baseline period (34-35% of energy from fat), followed by an 8-week low-fat (24 En%), low-cholesterol (279 mg/d) diet period and an 8-week switchback period. In this study population the apo B ins/del and XbaI polymorphisms exhibited mainly similar and partly significant effects on the responses of plasma very low-density lipoprotein (VLDL) and high density lipoprotein2 (HDL2) cholesterol to dietary changes. After consumption of the low saturated fat, low-cholesterol diet, ins/ins X - /X - homozygotes showed the greatest increase in VLDL cholesterol (p < 0.05 for differences between ins/del genotypes) and the greatest fall in HDL2 cholesterol (p = 0.01 for ins/del and p = 0.05 for XbaI), while only minimal alterations were seen in the del/del and X + /X + groups. After returning to the original diet, the changes of these lipids were reversed, ins/ins and X -/X - homozygotes having the greatest reductions in VLDL cholesterol (p < 0.05 for XbaI) and the greatest increases in HLDL2 cholesterol (p < 0.001 for XbaI). The findings suggest that plasma VLDL and HDL2 cholesterol responsiveness to diet may be partly explained by variation at the apo B gene.

Aged↗
PubMed1996

The relationship of bone and blood lead to hypertension. The Normative Aging Study.

OBJECTIVE: To test the hypothesis that long-term lead accumulation, as reflected by levels of lead in bone (as opposed to blood which reflects recent lead exposure), is associated with an increased odds of developing hypertension. DESIGN: Case-control study of participants in the Veterans Administration (now Department of Veterans Affairs) Normative Aging Study, a 30-year longitudinal study of men. PARTICIPANTS: Of 1171 active subjects who were seen between August 1991 and December 1994, 590 (50%) participated in this investigation and had data on all variables of interest. MAIN OUTCOME MEASURES: Hypertension was defined as taking daily medication for the treatment of hypertension or systolic blood pressure higher than 160 mm Hg or diastolic blood pressure of 96 mm Hg or higher during the time of examination. Levels of lead in the tibia (representing cortical bone) and the patella (representing trabecular bone) were measured in vivo with a K x-ray fluorescence (KXRF) instrument. Levels of lead in blood were measured by graphite furnace atomic absorption spectroscopy. RESULTS: Blood lead levels were low, ranging from less than 0.05 to 1.35 micromol/L (<1 to 28 microgram/dL), with a mean (SD) of 0.30 (0.20) micromol/L (6.3[4.1] microgram/dL). Bone lead levels were similar to those described in other general populations. In comparison to nonhypertensives, mean levels of lead in blood and both tibia and patella bone lead levels were significantly higher in hypertensive subjects. In a logistic regression model of hypertensive status that began with age, race, body mass index, family history of hypertension, history of ethanol ingestion, pack-years of smoking, dietary sodium intake, dietary calcium intake, blood lead, tibia lead, and patella lead, the variables that remained after backward elimination were body mass index, family history of hypertension, and level of lead in the tibia. An increase from the midpoint of the lowest quintile to the midpoint of the highest quintile of tibia lead from 3 to 37 micrograms per gram of bone mineral was associated with an increased odds ratio of hypertension of 1.5. CONCLUSION: Our findings suggest that long-term lead accumulation, as reflected by levels of lead in bone, may be an independent risk factor for developing hypertension in men in the general population.

Age Factors↗
PubMed1996

Dietary and environmental determinants of blood and bone lead levels in lactating postpartum women living in Mexico City.

Despite the recent declines in environmental lead exposure in the United States and Mexico, the potential for delayed toxicity from bone lead stores remains a significant public health concern. Some evidence indicates that mobilization of lead from bone may be markedly enhanced during the increased bone turnover of pregnancy and lactation, resulting in lead exposure to the fetus and the breast-fed infant. We conducted a cross-sectional investigation of the interrelationships between environmental, dietary, and lifestyle histories, blood lead levels, and bone lead levels among 98 recently postpartum women living in Mexico City. Lead levels in the patella (representing trabecular bone) and tibia (representing cortical bone) were measured by K X-ray fluorescence (KXRF). Multivariate linear regression models showed that significant predictors of higher blood lead included a history of preparing or storing food in lead-glazed ceramic ware, lower milk consumption, and higher levels of lead in patella bone. A 34 micrograms/g increase in patella lead (from the medians of the lowest to the highest quartiles) was associated with an increase in blood lead of 2.4 micrograms/dl. Given the measurement error associated with KXRF and the extrapolation of lead burden from a single bone site, this contribution probably represents an underestimate of the influence of trabecular bone on blood lead. Significant predictors of bone lead in multivariate models included years living in Mexico City, lower consumption of high calcium content foods, and nonuse of calcium supplements for the patella and years living in Mexico City, older age, and lower calcium intake for tibia bone. Low consumption of milk and cheese, as compared to the highest consumption category (every day), was associated with an increase in tibia bone lead of 9.7 micrograms Pb/g bone mineral. The findings of this cross-sectional study suggest that patella bone is a significant contributor to blood lead during lactation and that consumption of high calcium content foods may protect against the accumulation of lead in bone.

Adolescent↗
PubMed1996

Alpha-linolenic acid in rapeseed oil partly compensates for the effect of fish restriction on plasma long chain n-3 fatty acids.

OBJECTIVE: To examine the ability of alpha-linolenic acid (ALA) in low erucic acid rapeseed oil (RO) to compensate for the effects of a restriction in fish intake on plasma fatty acid composition. DESIGN AND SUBJECTS: Two times 6 weeks' randomized dietary intervention was used with blind crossover design in 40 healthy unconfined women and men (age 20-46y). INTERVENTIONS: Subjects were assigned to two fish restricted diets, namely RO diet and Trisun-sunflower oil (TSO) diet, with similar proportions of saturated : monounsaturated : polyunsaturated fatty acids (11.5:17.5:8.5% of total energy, En%), but differing in their ALA content (2.2 and 0.3 En%) and n-6 : n-3-ratio (3 : 1 and 23 : 1, respectively). The fatty acid compositions of plasma triglycerides (TG), cholesterol esters (CE), and phospholipids (PL) were analyzed by gas chromatography. Dietary intake was evaluated based on 3- to 7-day food records. RESULTS: The proportion of TG and CE ALA decreased on the TSO diet (from 1.6% to 0.9% and from 0.9% to 0.4%, respectively, P < 0.001) and increased on the RO diet (from 1.7% to 3.4% and from 0.9% to 1.3%, respectively, P < 0.001) compared to the baseline level. The proportion of eicosapentaenoic acid (EPA) in all three plasma fractions decreased on the TSO diet but not on the RO diet. The proportions of docosa-hexaenoic acid (DHA) decreased on both experimental diets and there was no difference in CE DHA between the diets. PL docosa-pentaenoic acid (DPA) and PL DHA remained at a higher level on the RO diet compared to the TSO diet (P < 0.001 and P < 0.05, respectively). CONCLUSIONS: ALA is metabolized to EPA in humans to a significant extent. The degree to which rapeseed oil (ca 50g/day) affects the proportion of EPA resembled the effect of a weekly portion (50-100g) of fatty fish depending on the fat content of the fish.

Adult↗
PubMed1996

Serum alpha tocopherol concentrations and cholesterol ester fatty acid composition in 70-year-old men reflect those 20 years earlier.

OBJECTIVE: It has been suggested that low serum alpha tocopherol concentrations and a low proportion of polyunsaturated fatty acids in the serum cholesterol esters may be associated with a high risk of developing coronary heart disease. DESIGN AND SUBJECTS: In this study the intraindividual reproducibility (biological 'tracking') of these variables was studied in 855 men at the ages of 50 and 70 years. RESULTS: The lipid adjusted tocopherol concentration was positively correlated (r = 0.28, P < 0.0001) between 50 and 70 years of age. Also the proportions of the serum cholesterol ester fatty acids were positively correlated between the same ages with r = 0.31 (P < 0.0001) for palmitic, r = 0.45 (P < 0.0001) for linoleic, and r = 0.58 (P < 0.0001) for arachidonic acid. The body weights of the men at 50 and 70 years of age were strongly correlated (r = 0.78, P < 0.0001). CONCLUSIONS: The tocopherol concentrations and the fatty acid composition are related to vitamin intake and to the dietary fat quality, respectively, and may be useful markers in prospective studies of diseases and of development of diseases. The correlations between the proportions of fatty acids and the body weights, respectively at the ages of 50 and 70 indicate, that changes in diet and body weight in men are probably relatively limited between these years.

Aged↗
PubMed1996

Predictors of adipose tissue tocopherol and toenail selenium levels in nine countries: the EURAMIC study. European Multicentre Case-Control Study on Antioxidants, Myocardial Infarction, and Cancer of the Breast.

OBJECTIVE: To evaluate the levels of adipose tissue alpha-tocopherol, gamma-tocopherol, and toenail selenium and their determinants. DESIGN: Control subjects from multicentre case-control study on antioxidants, myocardial infarction and cancer of the breast. SUBJECTS AND SETTING: 686 male and 339 female middle-aged and elderly subjects from eight European countries and Israel. RESULTS: The antioxidant levels were lower in men than women; adipose tissue alpha-tocophreol level in men was 75% of that in women, gamma-tocopherol 79% and toenail selenium 92%, respectively. In multiple regression analysis adjusting for age and centre waist circumference showed to be the only independent predictor of adipose tissue alpha-tocopherol level and waist/hip (W/H) ratio that of gamma-tocopherol level in men. In women no predictors of adipose tissue alpha-tocopherol or gamma-tocopherol level were found. Smoking and coffee use showed up to be the independent predictors of toenail selenium in men and smoking in women. Age, alcohol use, serum lipids, and reproductive factors were not related to the antioxidant levels. CONCLUSION: The inverse relationships of adipose tissue alpha-tocopherol and gamma-tocopherol levels with central fat distribution should be considered in studies relating the tocopherol levels to the development of chronic diseases in men, and the inverse relationship of toenail selenium with smoking both in men and women, and with coffee consumption in men, should be considered when toenail selenium level is used as a biomarker in epidemiological studies.

Adipose Tissue↗
PubMed1995

Adipose tissue isomeric trans fatty acids and risk of myocardial infarction in nine countries: the EURAMIC study.

Dietary isomeric trans fatty acids-mainly produced by hydrogenation of oils-are suspected of increasing the risk of coronary heart disease. Dietary trans fatty acid intake is reflected in the fatty acid composition of adipose tissue. In an international multicentre study in eight European countries and Israel (EURAMIC), adipose tissue aspiration samples were obtained from 671 men with acute myocardial infarction (AMI), aged 70 years or less, and 717 men without a history of AMI (controls). The proportion of fatty acids, including isomeric trans monoenoic fatty acids with 18 carbon atoms (C18:1), was determined by gas chromatography. Although there were considerable differences between countries in mean (SD) proportion of adipose tissue C18:1 trans fatty acids, there was no overall difference between cases (1.61 [0.92]%) and the controls (1.57 [0.86]%). The risk of AMI did not differ significantly from 1.0 over quartiles of adipose C18:1 trans fatty acids: the multivariate odds ratio was 0.97 (95% CI 0.56-1.67) for the highest versus lowest quartile. After exclusion of subjects from Spanish centres because they had far lower proportions of adipose trans fatty acids than subjects from other countries, there was a tendency to increased risk of AMI in the upper quartiles of C18:1 trans; however, the trend was not statistically significant. Our results reflect considerable differences between countries in dietary intake of trans fatty acids but do not suggest a major overall effect of C18:1 trans fatty acids on risk of AMI. We cannot exclude the possibility that trans fatty acids have a significant impact on risk of AMI in populations with high intake.

Adipose Tissue↗
PubMed1995

Effects of supplementation of fertilizers on human selenium status in Finland.

The Se concentration of foods can be increased by supplementing fertilizers with soluble Se compounds. In Finland the availability of soil Se for plants is poor owing to the relatively low Se concentration, low pH and high iron content of the soil. Since 1984 multimineral fertilizers have been supplemented with Se (16 mg kg-1 to fertilizers for grain production and 6 mg kg-1 to those for fodder production) in the form of sodium selenate. Within two years a three-fold increase of mean Se intake was observed. The supplementation affected the Se content of all major food groups with the exception of fish. The concomitant human serum Se concentration increased by 70%. In 1990 the amount of Se that was supplemented was reduced to 6 mg kg-1 for all fertilizers. This reduced the mean Se intake by 30% and the serum Se concentration decreased by 25% from the highest levels observed in 1989. Plants take up part of the supplemented selenate and transform it into organic Se compounds, mainly selenomethionine. This affects human nutrition by increasing the Se content of foods of both animal and vegetable origin. According to data obtained in Finland, supplementation of fertilizers with Se is a safe and effective means of increasing the Se intake of both animals and humans that is feasible in countries with relatively uniform geochemical conditions. This kind of intervention requires careful monitoring of the effects on both animal and human nutrition and the environment.

Fertilizers↗
PubMed1995

K x-ray fluorescence measurements of bone lead concentration: the analysis of low-level data.

K line x-ray fluorescence (KXRF) measurements of bone lead have emerged as a promising new biological marker of internal lead dose in epidemiological studies. Some disagreements exist, however, over the analysis of data at low levels of bone lead concentration. In this study, we performed 30 serial measurements on each of three phantoms containing spiked amounts of lead. Chemical analysis of these phantoms using an inductively coupled plasma mass spectrometer (ICPMS) indicated that the lead concentrations were 0.30, 5.77, and 11.57 micrograms g-1. Analysis of the data was performed using several definitions of a minimum detectable limit (MDL) to recode data below the MDL, and using all of the continuous point estimates of lead concentration in the phantom (including negative estimates). The results demonstrate that the use of MDLs to recode low-level observations reduces the efficiency of the analysis and the ability to distinguish between the phantoms. Retaining all point estimates of KXRF-measured bone lead concentration provides less bias and greater efficiency in comparing the mean or median levels of bone lead of different populations.

Analysis of Variance↗
PubMed1995

Association between beta-carotene and acute myocardial infarction depends on polyunsaturated fatty acid status. The EURAMIC Study. European Study on Antioxidants, Myocardial Infarction, and Cancer of the Breast.

Because antioxidants may play a role in the prevention of coronary heart disease by inhibiting the peroxidation of polyunsaturated fatty acids (PUFAs), the combined association of diet-derived antioxidants and PUFAs with acute myocardial infarction (MI) was investigated. This multicenter case-control study included 674 patients and 725 control subjects in eight European countries and Israel. Fatty acid composition and alpha-tocopherol and beta-carotene levels were determined in adipose tissue; selenium level was determined in toenails. For alpha-tocopherol no association with MI was observed at any PUFA level. The overall multivariate odds ratio (OR) for low (10th percentile) versus high (90th percentile) beta-carotene was 1.98 (95% confidence interval [CI], 1.39 to 2.82). The strength of this inverse association with MI was dependent on PUFA levels (in tertiles): for low PUFA, the OR for low versus high beta-carotene was 1.79 (95% CI, 0.98 to 3.25), for medium PUFA the OR was 1.76 (95% CI, 1.00 to 3.11), and for high PUFA 3.47 (95% CI, 1.93 to 6.24). For selenium increased risk was observed only at the lowest PUFA tertile (OR, 2.49; 95% CI, 1.22 to 5.09). This interaction between selenium and PUFAs was not significant and may at least partly be explained by a higher proportion of smokers at the low PUFA level. These findings support the hypothesis that beta-carotene plays a role in the protection of PUFAs against oxidation and subsequently in the protection against MI. No evidence was found that alpha-tocopherol or selenium may protect against MI at any level of PUFA intake.

Adipose Tissue↗
PubMed1995

Bone lead measured by X-ray fluorescence: epidemiologic methods.

In vivo X-ray fluorescence (XRF) measurement of bone lead concentration (XRF) has emerged as an important technique for future epidemiological studies of long-term toxicity. Several issues germane to epidemiologic methodology need to be addressed, however. First, sources of variability in measurements of bone lead need to be quantified, including imprecision related to the physical measurement itself and the variability of lead deposition over the two main compartments of bones (cortical vs. trabecular) and within each compartment. Imprecision related to the physical measurement can be estimated for each individual measurement based on the variability of the signal and background. Second, approaches to low-level data need to be debated. We argue for using the minimal detection limit (MDL) to compare instruments and interpret individual measurements; however, with regard to epidemiologic studies, we would abandon the MDL in favor of using all point estimates. In analyses using bone lead as an independent variable, statistical techniques can be used to adjust regression estimates based on estimates of measurement uncertainty and bone lead variability. Third, factors that can be expected to modify the relationship between bone lead and toxicity such as gravida history, endocrinological states, nutrition, and other important influences on bone metabolism, need to be identified and measured in epidemiologic studies. By addressing these issues, investigators will be able to maximize the utility of XRF measurements in environmental epidemiologic studies.

Bone and Bones↗
PubMed1994

Acarbose and nutrient intake in non-insulin dependent diabetes mellitus.

We carried out a double-blind, placebo-controlled cross-over trial to evaluate changes in nutrient intake during acarbose therapy and short-term changes in metabolic control in Finnish patients with non-insulin dependent diabetes mellitus. The efficacy and tolerability of acarbose was also assessed during this short 8-week treatment period. Patients were treated either with diet only (18 subjects) or with diet and sulphonylurea (9 subjects) prior to entering this trial. The nutrient intake was assessed using food records kept during the last 2-5 days of each treatment period. Treatment with acarbose did not affect body weight or the intake of energy and carbohydrates, but it was associated with a slight decrease in the dietary fat intake. Both fasting and 2-h postprandial blood glucose levels fell continuously during acarbose but the change did not reach statistical significance during the 8-week treatment period. The 2-h serum insulin response was not affected. The results were similar in patients treated with acarbose alone and in those receiving acarbose together with sulphonylurea regimen. The acarbose regimen was relatively well tolerated although mild gastrointestinal side-effects were observed in many patients. In conclusion, treatment with acarbose has no major effects on nutrient intake in diabetic patients. To monitor changes in metabolic control after the introduction of acarbose to the treatment regimen a longer than 8-week period is needed.

Acarbose↗
PubMed1994

Factors affecting the selenium intake of people in Transbaikalian Russia.

The selenium concentration in foods grown and consumed and in plasma, red blood cells, and toenails of people living in the district of Chita in the transbaikalian part of Russia were studied in August 1991. Preliminary results from the area have suggested low selenium intakes and the possible occurrence of cardiomyopathy (Keshan disease) in the population. A low selenium concentration in foods grown locally was found: mean selenium concentration in wheat grains was 1, 5, and 28 micrograms/kg, respectively, in three villages studied, that of oats was between 3-6 micrograms/kg, and of cow's milk 10-27 micrograms/kg dry matter. The selenium concentration of bread was considerably higher, between 87-337 micrograms/kg dry wt, presumably because wheat imported from the US had been used for baking. Occasional samples of pork, beef, and mutton contained between 32-218 micrograms selenium/kg dry wt. Low selenium concentrations were observed in samples of soil and river water. The mean plasma selenium concentration of 52 persons was 1.02 mumol/L, including 33 children and 19 adult subjects. The selenium concentrations in red blood cells and toenails were 1.95 mumol/L and 0.61 mg/kg, respectively. No symptoms of heart disease caused by selenium deficiency were observed. It is concluded that the selenium status of people was fairly good thanks to the contribution to dietary intake of imported wheat with a high selenium content. As the selenium concentration was very low in foods grown in the area, the selenium intake of the population will be reduced to a very low level if only locally produced foods are consumed.

Adolescent↗
PubMed1994

Diet, cow's milk protein antibodies and the risk of IDDM in Finnish children. Childhood Diabetes in Finland Study Group.

Associations of infant feeding patterns and milk consumption with cow's milk protein antibody titres were studied in 697 newly-diagnosed diabetic children, 415 sibling-control children and 86 birth-date- and sex-matched population-based control children in the nationwide "Childhood Diabetes in Finland" study. IgA and IgG antibody titres to the proteins of cow's milk formula, BLG and BSA, and IgM antibody titres to cow's milk formula proteins were measured by ELISA. Several inverse correlations were observed between the duration of breast-feeding or age at introduction of dairy products and antibody titres, and positive correlations were observed between milk consumption and antibody titres in all three populations studied. Multivariate analyses which included the infant feeding variables, milk consumption and current age simultaneously showed that the earlier the introduction of dairy products and the greater the consumption of milk was, the higher several antibody titres were. High IgA antibody titres to cow's milk formula were associated with a greater risk of IDDM both among diabetic-population-control and diabetic-sibling-control pairs when adjusted for other cow's milk antibody titres, dietary variables and in diabetic-sibling-control pairs also for ICA. The results suggest that young age at introduction of dairy products and high milk consumption during childhood increase the levels of cow's milk antibodies and that high IgA antibodies to cow's milk formula are independently associated with increased risk of IDDM.

Adolescent↗
PubMed1994

Long-term effects of three fat-modified diets in hypercholesterolemic subjects.

Altogether 160 free living subjects (aged 30-60 years) most of whom had moderate hypercholesterolemia were randomised into the following diet groups to find out long-term effects of different fat-modified diets: (1) control diet 35/14:10:4 (energy percents from fat/saturated:monounsaturated:polyunsaturated fatty acids in actual diets); (2) AHA type diet 32/10:8:8; (3) monoene-enriched diet 34/11:11:5; (4) reduced-fat diet 30/12:8:3. LDL cholesterol fell equally with the AHA type diet (4.54 +/- 0.97 vs. 4.21 +/- 0.89 mmol/l (mean +/- S.D., 0 vs. 6 months), P = 0.001) and with the monoene-enriched diet (4.55 +/- 0.95 vs. 4.25 +/- 0.95 mmol/l, P = 0.004) during the 6-month study. Moderate amounts of polyenes or monoenes as part of natural diets did not decrease HDL cholesterol level in the long term. Serum lipid values remained unchanged with the reduced-fat diet. Analysis by apolipoprotein E phenotypes showed a decrease in LDL cholesterol only in subjects with phenotype 3/3 in the monoene-enriched group (-8.6 +/- 8.7 vs. +1.3 +/- 15.4, percent change in LDL cholesterol E 3/3 vs. E 4/3 + 4/4), but in the AHA type group LDL cholesterol decreased similarly in phenotypes E 3/3 and E 4/3 + 4/4 (-6.9 +/- 10.1 vs -6.9 +/- 16.5).

Adult↗
PubMed1994

The risk to develop NIDDM is related to the fatty acid composition of the serum cholesterol esters.

This investigation was undertaken to study whether the risk to develop non-insulin-dependent diabetes mellitus (NIDDM) among 50-year-old men during a 10-year follow-up period was related to the fatty acid composition of their serum cholesterol esters. There were highly significant differences in the initial health survey between the fatty acid composition in serum in subjects who remained normoglycemic (n = 1,753) and in those who later developed NIDDM (n = 75). The main differences were that the latter had higher proportions of saturated fatty acids and palmitoleic acid (16:1 omega-7), a low proportion of linoleic acid (18:2 omega-6), and a relatively high content of gamma-linolenic (18:3 omega-6) and dihomo-gamma-linolenic (20:3 omega-6) acids in the serum cholesterol esters. The picture was similar also after adjusting for differences in body mass index. In a logistic model, a high proportion of dihomo-gamma-linolenic acid remained a significant contributor to the development of diabetes, along with the height of the insulin index, the blood glucose concentration at 60 min, and the fasting insulin concentration. The increased risk to develop NIDDM related to the serum cholesterol ester fatty acid composition may be mediated by diet and/or genetic factors.

8,11,14-Eicosatrienoic Acid↗