Biomedical subjects

N A Kaufmann

Publications and source records attributed to N A Kaufmann.

At least 19 recordsLinked to original sources

PubMed1995

Physical activity within a community-based weight control program: program evaluation and predictors of success.

OBJECTIVES: To assess the feasibility and effectiveness of adding physical activity sessions to a weight control program in a community health center and to identify individuals suitable for outpatient group treatment with and without physical activity. METHODS: The study population included 42 overweight women who were randomly divided into treatment groups. Both treatment groups received guidance in nutrition and behavior modification and the exercise group also participated in physical activity sessions. Both treatments included 20 sessions and participants were followed up for eight months. RESULTS: In both treatments, significant improvements were seen in physical fitness, anthropometric measurements, nutritional knowledge, food consumption, and eating behaviors. Weight loss following three months of weekly sessions did not differ by treatment group. At follow-up there was a trend towards increased maintenance of weight loss in the exercise group, however differences were not statistically significant. Attrition rates were low in both treatments and participant satisfaction was high. Lower baseline BMI predicted larger weight losses, in particular in the exercise group. Other predictors of weight loss included poorer baseline eating behaviors and employment outside of the home. Perceived spouse support predicted continual participation.

Adult↗

PubMed1993

The role of XbaI polymorphism of the apolipoprotein B gene in determining levels and covariability of lipid and lipoprotein variables in a sample of Israeli offspring with family history of myocardial infarction.

We have determined the frequency of DNA polymorphism of the gene for human apolipoprotein B detected with XbaI in 525 Israeli offspring whose parents experienced a myocardial infarction. The relative frequencies of the X1 (8.6 kb) and X2 (5.0 kb) alleles were 0.67 and 0.33, respectively, with no significant differences between males and females and across the different origin groups. Significant variation in sex, age and body mass adjusted plasma levels of cholesterol (P = 0.02), LDL-C (P = 0.02) and apo B (P = 0.03) were associated with the XbaI polymorphism. An interaction with age was demonstrated. For young individuals a simple codominant association of the XbaI site with cholesterol and LDL-C was evident and the differences between the two homozygote groups ranged between 22 and 25 mg/dl. For individuals above age 25 these differences were about 12 mg/dl with no significant difference between the X1X2 and the X2X2 genotype groups. In our study sample the apo B XbaI polymorphism accounted for 1% of the variability of plasma cholesterol, LDL-C and apo B levels. The XbaI polymorphism also had an effect on the associations among lipid and lipoprotein variables. In conclusion, we have demonstrated an association of the apo B XbaI polymorphism with the metabolism of the apo B-containing lipoprotein particles in a sample of Israeli offspring with a family history of myocardial infarction.

Adult↗

PubMed1993

XbaI polymorphism of the apolipoprotein B gene and plasma lipid and lipoprotein response to dietary fat and cholesterol: a clinical trial.

A dietary trial was carried out on a group of offspring whose parents were hospitalized for an acute myocardial infarction. The XbaI Restriction Fragment Length Polymorphism (RFLP) was used to examine the genetic contribution of variation at this apo B locus to the response of lipids and lipoproteins to dietary manipulations. Twenty participants were homozygotes for the 8.0 kb fragment (X1X1), two were homozygotes for the 5.0 kb fragment (X2X2), and 15 were heterozygotes (X1X2). Subjects were randomized to a 5-week crossover study. Half began on a low SFA--cholesterol (LSC) diet for 5 weeks and, after a washout period of 4 weeks, they were placed on a high SFA--cholesterol (HSC) diet for a second period of 5 weeks. This order was reversed in the second group of participants. Significant changes in total cholesterol, LDL-C, and apo B were observed when subjects were moved from the LSC to the HSF diet. The corresponding average change induced by the dietary manipulations in X1X1 subjects compared with subjects with X2 allele were: 18.1 +/- 17.6 mg/dl and 9.5 +/- 19.6 mg/dl for total cholesterol and 15.8 +/- 15.3 mg/dl and 4.8 +/- 20.9 mg/dl for LDL-C, respectively. Our observation indicated that variation at the apo B XbaI locus may interact with baseline levels to determine individual dietary response in LDL-C level. However, the differences between the genotypic classes were not statistically significant, suggesting that the apo B XbaI locus is not a major determinant of interindividual differences in lipid and lipoprotein response to diet in this population.

Adult↗

PubMed1992

Effects of diets rich in monounsaturated fatty acids on plasma lipoproteins--the Jerusalem Nutrition Study. II. Monounsaturated fatty acids vs carbohydrates.

Seventeen male Yeshiva students were randomly allocated to a crossover study with two 12-wk dietary periods of monounsaturated fatty acids (MUFAs) vs a carbohydrate (CHO)-rich diet while concentrations of saturated (SFAs) and polyunsaturated (PUFAs) fatty acids were kept similar. Total plasma cholesterol (TC) decreased significantly by approximately 7.7% and low-density-lipoprotein cholesterol (LDL-C) by 14.4% on the MUFA diet, whereas on the CHO diet no significant change in cholesterol concentrations occurred, in contrast to that predicted by the equations of Keys and Hegsted. Concentrations of high-density-lipoprotein cholesterol (HDL-C) did not change significantly on either diet. On the MUFA diet there was a significantly lower proneness to peroxidation of plasma and LDL lipids and less extensive metabolism of conditioned LDL by peritoneal macrophages. We conclude that dietary MUFAs lower TC and LDL-C concentrations, independently of other dietary fatty acids and in addition may reduce the susceptibility of LDL to oxidative stress.

Adult↗

PubMed1991

Effects of diets rich in monounsaturated fatty acids on plasma lipoproteins--the Jerusalem Nutrition Study: high MUFAs vs high PUFAs.

Twenty-six Yeshiva students were randomly assigned to a 24-wk crossover study of monounsaturated fatty acid (MUFA) vs polyunsaturated fatty acid (PUFA) diets (50% carbohydrate, 32% fat, 18% protein) fed alternately during two 12-wk periods. Total plasma cholesterol (TC) decreased significantly by approximately 10% and approximately 16% on the MUFA and PUFA diets, respectively. Plasma triglyceride response was variable. Low-density-lipoprotein cholesterol (LDL-C) decreased in both groups with an additional significant effect between periods. Concentrations of high-density-lipoprotein cholesterol did not change significantly. LDL-receptor status in fresh monocytes, affinity of LDL towards the LDL receptor in cultured fibroblasts, zonal-centrifugation profiles, and lipoprotein composition were not significantly different between the diets. There was a significantly higher tendency toward lipid peroxidation on the PUFA diet, as ascertained by more thiobarbituric acid-reactive-substances formation on that diet. Dietary PUFA results in somewhat lower TC and LDL-C concentrations whereas with MUFA the susceptibility of LDL to oxidative stress is lower.

Binding, Competitive↗

PubMed1988

Serum ferritin levels in preterm infants after multiple blood transfusions.

We have examined the effect on iron stores of blood transfusions given to premature neonates during hospitalization in the neonatal intensive care unit as reflected by serum ferritin levels measured for 6 months after discharge. Premature infants who were transfused with more than 100 ml packed cells (group D; n = 11) had higher ferritin levels for a longer period than premature infants who were transfused with smaller volumes (group c; n = 9) or premature and mature infants who were not transfused at all (group B; n = 24 and group A; n = 21, respectively). At 4-5 months the serum ferritin levels in group D (489.8 +/- 132.1 micrograms/L; mean +/- SEM) were significantly higher (P less than 0.001) than those of the other groups. The level of group A term infants (77.5 +/- 12.5 micrograms/L) was higher than those of group B premature infants who did not receive a blood transfusion (33.0 +/- 7.1 micrograms/L) or group C who received less than 100 ml (36.5 +/- 8.8 micrograms/L packed red blood cells. However, these differences were not statistically significant. Our data demonstrate that very-low-birthweight infants who receive a large volume of packed cells during hospitalization may accumulate iron stores sufficient for red cell production during the first 6 months of life. Administration of large amounts of supplemental iron, in such cases, may be curtailed.

Anemia, Hypochromic↗

PubMed1988

Familial aggregation of body mass index in ethnically diverse families in Jerusalem. The Jerusalem Lipid Research Clinic.

Familial aggregation of body mass index in different ethnic populations was studied in a sample of nearly 4000 families resident in Jerusalem. Covariate adjustments were applied to body mass index (BMI) to adjust for variation in means and variances with sex, age and origin and for the effect of education, socioeconomic status and seasonality. The analyses were done separately in each of the origin groups categorized according to the parents' country of birth (Europe, Asia, North Africa, Israel/mixed origin), in order to account for the heterogeneity among the groups. Parent-child correlations were generally homogeneous across the origin groups. Sibling correlations for BMI differed to a greater extent among the groups. The highest correlation was observed in the Asian group (r = 0.49) and the lowest in the North African group (r = 0.16). Pooled correlations among biological relatives across the origin groups were highly significant. Spouse correlation, although significant was smaller, suggesting a stronger influence of genes than shared environment in the determination of the trait. Father-child correlation was significantly higher (r = 0.25) than mother-child value (r = 0.19), suggesting a possible paternal influence on BMI. There was also asymmetry in parent-offspring correlations by the sex of the offspring. Sibling correlation was higher (r = 0.33) than parent-offspring correlation (r = 0.22), suggesting that shared environment within generations tended to have some importance.

Adolescent↗

PubMed1986

Comparison of nutrient intakes of selected populations in the United States and Israel: the Lipid Research Clinics prevalence study.

Nutrient intakes of 2,772 US and 2,680 Jerusalem participants of the Lipid Research Clinics Program were assessed by 24-h dietary recall in men aged 15-19 and 40-59 yr and women aged 15-19 and 35-59 yr. Energy intake was higher in the US than in Jerusalem. In Jerusalem intake of total fat ranged between 32.2-33.7% of kcal, of saturated fatty acids (SFA) between 9.8-10.9%, of polyunsaturated fatty acids (PFA) between 7.9-8.6%, of carbohydrates between 50.5-53.9%, and of starch between 24.0-30.5%. The P:S ratio ranged between 0.80 and 1.01. The corresponding ranges for the US were 38.8-40.8% for fat, 14.3-15.9% for SFA, 5.9-6.8% for PFA, 38.9-46.2% for carbohydrates, 17.0-17.9% for starch, and 0.40-0.53 for the P:S ratio. Intake of cholesterol (mg/1000 kcal) was higher in Jerusalem than in the US. These data address the feasibility of reducing fat in diets of free-living, Western populations.

Adolescent↗

PubMed1986

Effect of moderate isocaloric modification of dietary carbohydrate on high-density lipoprotein composition and apolipoprotein A-1 turnover in humans.

Plasma lipid and apolipoprotein (apo) levels were determined in five normolipidemic subjects and five patients with Type IV hypertriglyceridemia (HTG) who were fed for greater than or equal to 6 weeks on two isocaloric diets. The first diet contained carbohydrates (CHO) as 55% of total calories, 29% as fat and 16% as protein. The second diet contained 40% CHO, 45% fat and 15% protein in normolipidemic subjects and 40% CHO, 41% fat and 19% protein in patients with HTG. All diets had a cholesterol content of approximately 400 mg/day and a polyunsaturated/saturated fatty acid ratio of approximately 1:0. Apo A-1 kinetics were measured during the last 2 weeks of each dietary period. The composition and distribution of high-density lipoproteins (HDL), subclasses HDL2 and HDL3, were determined at the end of each dietary term. In the HTG patients, administration of a 40% compared with 55% CHO diet caused a significant decrease of plasma triglyceride levels and an increase of HDL-cholesterol; low-density lipoprotein (LDL) levels increased and very low-density lipoprotein (VLDL) levels decreased (P less than 0.01 and less than 0.07, respectively). Similar quantitative changes of VLDL and HDL levels were found in the normolipidemic subjects. No significant change in plasma levels of apo A-I, A-II and E occurred. Apo A-I kinetic studies revealed decreased synthetic rates and fractional catabolic rates on the low CHO diet. Separation of HDL subfractions by zonal ultracentrifugation in both groups revealed an increase in HDL3-cholesterol ester and protein, and a decrease in HDL2 protein, phospholipid and cholesterol. Our findings indicate that moderate changes in dietary CHO and fat content affect HDL levels, composition and apo A-I metabolism.

Adult↗

PubMed1985

Coffee, tea, and plasma cholesterol: the Jerusalem Lipid Research Clinic prevalence study.

The association of intake of coffee and tea, assessed by 24 hour dietary recall, with plasma cholesterol and its lipoprotein fractions was studied in a sample of 1007 men and 589 women aged 35-64 resident in Jerusalem. These cross sectional data showed a significant linear association (p less than 0.001) between consumption of coffee in men and plasma cholesterol and low density lipoprotein cholesterol concentrations. Men who drank five cups of coffee or more had plasma cholesterol concentrations about 0.5 mmol/l (20 mg/100 ml) higher than non-drinkers after controlling for age, ethnicity, body mass, education, season of year, smoking, tea drinking, and dietary intake of fat and carbohydrates. In women adjusted mean plasma cholesterol concentration was 0.34 mmol/l (13 mg/100 ml) higher in coffee drinkers grouped together (p less than 0.01). The test for a linear trend was not significant. The association in both sexes was largely with the low density lipoprotein cholesterol fraction. High density lipoprotein cholesterol concentrations were somewhat increased in women who drank coffee (p less than 0.01 for a linear trend) but not in men. Tea drinking was not associated with unadjusted plasma cholesterol concentrations in either sex. Male tea drinkers, but not female, had slightly higher adjusted plasma cholesterol concentrations than non-drinkers (0.15 mmol/l (6 mg/100 ml), p = 0.04). No dose response relation was evident. In this population, characterised by a low intake of saturated fatty acids and relatively low mean plasma cholesterol concentrations, coffee drinking may be a determinant of low density lipoprotein cholesterol concentrations.

Adult↗

PubMed1985

Coronary heart disease risk factors among religious groupings in a Jewish population sample in Jerusalem.

The hypothesis that plasma lipids, blood pressure, smoking and dietary intake differed according to degree of religiosity was examined in a sample of Jewish residents of Jerusalem. Religiosity was classified according to the subject's self-ranking of his perceived degree of religiosity. Prevalence of smoking, and plasma levels of cholesterol, triglycerides, and low-density lipoprotein cholesterol were higher in secular participants than in the orthodox group. No differences in blood pressure and in high-density lipoprotein cholesterol were observed. Secular subjects consumed more total fat, more saturated fatty acids and less carbohydrate than religious subjects. These differences in nutrient intake among the religious groups reflected differences in their food selection, notably consumption of dairy products. These findings of parallel differences in plasma lipids and in dietary intake are consistent with the differing incidence of myocardial infarction in the religious groups which has been shown in the Israeli population.

Adolescent↗

PubMed1984

Admixture analysis of plasma cholesterol levels in a Jewish population sample in Jerusalem.

The frequency distribution of total plasma cholesterol levels (TC) in 17-year-old Jerusalem youngsters and their parents (n = 6,170) was examined for evidence of admixture of normal distributions. Probability plots indicated bimodality of age-adjusted TC in both sexes. Using a maximum likelihood procedure, two normal distributions fitted the age- and sex-adjusted data significantly better than 1, with 0.9% males and 1.2% females coming from a lower distribution 2-3 standard deviations below the major mode and 0.2% males and 1.1% females belonging to the higher distribution. These results suggest that single genes may determine high as well as low cholesterol levels, but are open to other interpretations, and thus require confirmation by segregation analysis. Jews originating from Europe showed the highest TC levels followed by those from Israel, Asia, and Africa. Adjustment of TC for ethnicity did not alter the above estimates. Analysis of bimodality within countries of origin showed greater separation of the distributions in Asian and Israeli origin groups than in European and North African groups, in whom there was less evidence for admixture.

Adolescent↗

PubMed1984

Determinants of thyroid hormone and thyroid-lipid interrelationships in Jerusalem.

In a study of 652 boys and 556 girls, aged 17, and 1,020 men and 575 women from the Jerusalem Lipid Research Clinic, serum thyroxine was higher in females than in males and higher in 17-year-old boys than in men. In most age- and sex groups, thyroxine was highest in Israelis originating from Asian and other Middle Eastern countries and lowest in immigrants or children of immigrants from Western countries. As in other population-based studies, we found a statistically significant negative correlation between thyroxine and triglyceride in adult males and negative correlations between thyroxine and high-density lipoprotein-cholesterol in all age- and sex groups. No associations between thyroxine and low-density lipoprotein-cholesterol or very low-density lipoprotein-cholesterol were observed.

Adolescent↗

PubMed1982

The Jerusalem Lipid Research Clinic: sampling, response and selected methodological issues.

The Jerusalem Lipid Research Clinic examined 8,646 17-yr-old youngsters and 6,952 of their parents in order to obtain information on the distribution of plasma lipids and lipoproteins in the free-living multiethnic population of Jerusalem. Sampling procedures and recruitment methods are described, and the degree to which the study population was representative of the target population is addressed in detail. Sources of response bias, although not likely to have influenced the results of analyses to date, are identified, and biased portions of the sample will be excluded from further analyses. Selected methodological problems unique to the Jerusalem Lipid Research Clinic are discussed.

Adolescent↗

PubMed1982

Plasma lipids and lipoproteins in adult Jews of different origins: the Jerusalem Lipid Research Clinic prevalence study.

Plasma cholesterol, triglyceride (TG) and high-density lipoprotein-cholesterol (HDL-C) were measured in a cross-sectional sample of 6,952 middle-aged Jerusalem residents in 1976-79, using the protocols and methods of the North American Lipid Research Clinics (LRC) prevalence studies. There were highly significant variations between groups of Jews of different origin. Age-adjusted levels of total cholesterol were about 10 mg/dl higher in European- and Israeli-born men and women than in immigrants from North Africa or Asia. TG levels showed a similar pattern in men, but the reverse in women. HDL-C levels were 2 to 4 mg/dl higher in European- and Israeli-born women than in female immigrants from Asia or North Africa. In men there was little variation of HDL-C by origin, but males showed significant ethnic differences in the proportion of HDL-C in total cholesterol, while females did not.

Adult↗

PubMed1982

Contributions of different lipoprotein fractions to variations in total cholesterol between Israeli origin groups and social classes.

Total cholesterol, triglycerides and high-density lipoprotein (HDL)-cholesterol were measured in 2,306 boys, 1,716 girls, 2,479 fathers and 2,822 mothers examined on Visit 1 of the Jerusalem Lipid Research Clinics Prevalence Study in 1976-79. Low-density lipoprotein (LDL)-cholesterol levels were estimated from the other three measurements. Using multiple regression analysis to control for body mass index, social class, season of the year and (in parents) age, we compared the three origin groups (Asian, North African and European, depending on the birthplace of the parents) with the Israeli-born group. In both fathers and mothers, the lower total cholesterol levels in the North African group, and to a lesser extent in the Asian, were explained mainly by lower LDL-cholesterol in these groups. In youngsters, the origin groups were characterized by differences not only in LDL-cholesterol, but also in other lipoprotein fractions. Social class in youngsters and mothers was associated mainly with the HDL-cholesterol fraction; in fathers it was associated only with triglycerides. Possible relationships of these findings to smoking, alcohol, exercise and female sex hormones are discussed.

Adolescent↗

PubMed1982

Reported physical activity and blood lipids in Jerusalem adults.

The association of physical activity and fasting plasma lipids and lipoproteins was studied in an adult Jerusalem population consisting of 1,095 men and 614 women. Participants were questioned about habitual physical activity, and the relationship of their reported levels of activity of fasting lipid and lipoprotein values was examined. After adjustment was made for age, ethnic origin, body mass, season, cigarette smoking and alcohol consumption, the following associations were found: 1) an inverse association of reported physical activity with triglyceride, total cholesterol and very low-density lipoprotein-cholesterol (not significant), and 2) a significant positive association between reported activity and high-density lipoprotein-cholesterol in men. These findings generally confirm results found in other Western populations. Too few women reported moderate or strenuous physical activity to permit an examination of lipid associations in women.

Adult↗

PubMed1982

Nutrient intake in Jerusalem--consumption in 17-year-olds.

The food intake of 17-yr-old Jerusalem residents was assessed in a random sample, including 627 males and 551 females, by a 24-h dietary recall method. The intake of energy in boys and girls was lower than the recommended energy intake for this age, but the intake relative to body weight was low only in girls. In boys and girls, the intakes of fat relative to energy were 32.4 and 33.7%, respectively; those of saturated fatty acids (SFA) (9.8 and 10.5%) were lower and those of carbohydrates (53.9 and 52.5%) were higher than intakes found in other Western countries. The P:S (polyunsaturated to saturated fatty acids) ratio of their diets was high and ranged from 0.79 to 1.29 in various sex and origin groups. Intake of cholesterol per 1,000 kcal was similar to that in Western countries. There were marked differences in nutrient intake of subjects whose fathers had immigrated from different countries. Boys whose fathers were born in Israel or Europe had higher intakes of fat and cholesterol, and both boys and girls had a higher intake of SFA and a lower intake of carbohydrates and starch as well as a lower P:S ratio than did their counterparts whose fathers were born in Asia and North Africa. Thus, the nutrient intake of youngsters in Jerusalem differs markedly from that of populations in other Western countries.

Adolescent↗