Popular diets: correlation to health, nutrition, and obesity.

OBJECTIVE: To examine the association between a range of health and nutrition indicators and popular diets. DESIGN: The Continuing Survey of Food Intake by Individuals (CSFII) 1994-1996 data were used to examine the relationship between prototype popular diets and diet quality as measured by the healthy eating index (HEI), consumption patterns, and body mass index (BMI). The prototype diets included vegetarian (no meat, poultry, or fish on day of survey) and non-vegetarian. The nonvegetarian group was further subdivided into low carbohydrate (less than 30% of energy from carbohydrate), medium (30% to 55%), and high (greater than 55% of energy). Within the high carbohydrate group, participants were classified as having Pyramid or non-Pyramid eating patterns. The Pyramid group was defined as 30% or less of energy from fat and at least one serving from the five major food groups in the USDA Food Guide Pyramid. Finally, the non-Pyramid group was further subdivided into low fat (less than 15% of energy from fat) and moderate fat (15% to 30% of energy from fat). In addition, a review of the published scientific literature was conducted; all studies identified were included in the review. SUBJECTS: 10,014 adults, aged 19 years and older, from the 1994-1996 CSFII were included in the analyses of extant data. More than 200 individual studies were included in the review of the literature. RESULTS: Analyses of the CSFII indicate that diet quality as measured by HEI was highest for the high carbohydrate Pyramid group (82.9) and lowest for the low carbohydrate group (44.6). Energy intakes were low for the vegetarians (1,606 kcals) and high carbohydrate/low fat group (1360 kcals). BMIs were lowest for women in the vegetarian group (24.6) and the high carbohydrate/low fat group (24.4); for men, the lowest BMIs were observed for vegetarians (25.2) and the high carbohydrate Pyramid group (25.2). Review of the literature suggests that weight loss is independent of diet composition. Energy restriction is the key variable associated with weight reduction in the short term. CONCLUSIONS: Diets that are high in carbohydrate and low to moderate in fat tend to be lower in energy. The lowest energy intakes were observed for those on a vegetarian diet. The diet quality as measured by HEI was highest for the high carbohydrate groups and lowest for the low carbohydrate groups. The BMIs were significantly lower for men and women on the high carbohydrate diet; the highest BMIs were noted for those on a low carbohydrate diet.

Summary of the round table discussion on strategies for cancer prevention: diet, food, additives, supplements, and drugs.

A Round Table Discussion was held at the Fourth International Conference on Anticarcinogenesis and Radiation Protection. Scientists from government and academia were brought together to discuss the evidence for the preventive effect of foods, specific nutrients and drugs against cancer, and the most appropriate methods of initiating nutritional cancer prevention activities to improve the health of the public. The panel reviewed the epidemiological evidence of the role of diet and specific micronutrients for the prevention of cancer, the doses of specific micronutrients required for preventive effects and their safety, the evidence for aspirin as a chemopreventive agent, the issue of foods versus specific micronutrients in the prevention of cancer, food safety, and approaches to prevention such as food fortification or dietary supplements. The remarks of the panel members are summarized.

Gender-related traits and gender ideology: evidence for a multifactorial theory.

Male (n = 95) and female (n = 221) college students were given 2 measures of gender-related personality traits, the Bem Sex-Role Inventory (BSRI) and the Personal Attributes Questionnaire, and 3 measures of sex role attitudes. Correlations between the personality and the attitude measures were traced to responses to the pair of negatively correlated BSRI items, masculine and feminine, thus confirming a multifactorial approach to gender, as opposed to a unifactorial gender schema theory.

Workaholism: definition, measurement, and preliminary results.

Questionnaires were developed to assess the concept of workaholism, defined in terms of high scores on measures of work involvement and driveness and low scores on a measure of enjoyment of work, and to contrast this profile with work enthusiasm, defined as high work involvement and enjoyment and low driveness. Additional scales were devised to test several predictions about the correlates of workaholism. A test battery including these scales was given in a mail survey to a national sample of male (n = 134) and female (n = 157) social workers with academic positions. The psychometric properties of the scales are described. Cluster analyses for each sex revealed groups who corresponded to the workaholic and work enthusiast profiles as well as several other profiles. As predicted, workaholics were higher than work enthusiasts (among other groups) on measures of perfectionism, nondelegation of responsibility, and job stress. They were also higher on a measure of health complaints. Investigations are being initiated to determine the association of workaholism and other score profiles with objectively diagnosed cardiac disorders and with measures of occupational performance.

Psychological determinants of health and performance: the tangled web of desirable and undesirable characteristics.

Correlations were determined for male (n = 225) and female (n = 242) college students between sets of undesirable personality traits (anxiety, stress reactivity, anger, and alienation) and desirable personality traits (instrumentality, achievement strivings, and optimism measured by the Scheier-Carver [1987] Life Orientation Test), and a series of outcome variables related to health (self-reported health complaints and health maintenance behaviors and beliefs) and academic performance (academic expectations and actual grade point average). Significant correlations were found between many of the personality variables and the outcome variables. However, partial correlations revealed different relationships for the various criteria. With other variables held constant, health complaints were related to several undesirable characteristics, whereas health maintenance behaviors and beliefs were related to several desirable attributes. Only achievement strivings made an independent contribution in both sexes to the 2 measures of academic performance. The theoretical and methodological wisdom of using measures of multiple personality constructs and outcome variables is discussed.

Microcoulometric analysis of trimethylamine dehydrogenase.

Trimethylamine dehydrogenase, which contains one covalently bound 6-S-cysteinyl-FMN and one Fe4S4 cluster per subunit of molecular mass 83,000 Da, was purified to homogeneity from the methylotrophic bacterium W3A1. Microcoulometry at pH 7 in 50 mM-Mops buffer containing 0.1 mM-EDTA and 0.1 M-KCl revealed that the native enzyme required the addition of 3 reducing equivalents per subunit for complete reduction. In contrast, under identical conditions the phenylhydrazine-inhibited enzyme required the addition of 0.9 reducing equivalent per subunit with a midpoint potential of +110 mV. Least-squares analysis of the microcoulometric data obtained for the native enzyme, assuming uptake of 1 electron by Fe4S4 and 2 electrons by FMN, indicated midpoint potentials of +44 mV and +36 mV for the FMN/FMN.- and FMN.-/FMNH2 couples respectively and +102 mV for reduction of the Fe4S4 cluster.

Making it without losing it: Type A, achievement motivation, and scientific attainment revisited.

In a study by Matthews, Helmreich, Beane, and Lucker (1980), responses by academic psychologists to the Jenkins Activity Survey for Health Prediction (JAS), a measure of the Type A construct, were found to be significantly, positively correlated with two measures of attainment, citations by others to published work and number of publications. In the present study, JAS responses from the Matthews et al. sample were subjected to a factor analysis with oblique rotation and two new subscales were developed on the basis of this analysis. The first, Achievement Strivings (AS) was found to be significantly correlated with both the publication and citation measures. The second scale, Impatience and Irritability (I/I), was uncorrelated with the achievement criteria. Data from other samples indicate that I/I is related to a number of health symptoms. The results suggest that the current formulation of the Type A construct may contain two components, one associated with positive achievement and the other with poor health.

Stoichiometry of electron uptake and oxidation-reduction midpoint potentials of NADH:nitrate reductase.

Microcoulometric titrations of NADH:nitrate reductase at 25 degrees C in Mops buffer, pH 7.0, showed that the native enzyme, containing functional FAD, haem and Mo, required addition of five electrons for complete reduction. Reduction of the native enzyme occurred in three waves corresponding to addition of reducing equivalents to the centres in the order: Mo, haem, FAD. Oxidation-reduction midpoint potentials (E'0) for the various redox couples were calculated to be as follows: MoVI/MoV, +16 mV; MoV/MoIV, -27 mV; haemoxidized/haemreduced, -172 mV; FAD/FADH2, -283 mV. The values for the haem and flavin are in excellent agreement with those obtained by visible titrations, namely -164 mV and -288 mV respectively. In contrast, the results for the Mo centre are 28-50 mV more positive than the values previously determined by e.p.r. analysis of frozen enzyme samples poised at defined potentials at 25 degrees C and suggest different pH-dependencies or entropies of reduction for the Mo couples.

Role of protein synthesis in the carbohydrate-induced changes in the activities of acetyl-CoA carboxylase and hydroxymethylglutaryl-CoA reductase in cultured rat hepatocytes.

Changes in the activities of acetyl-CoA carboxylase and HMG-CoA (3-hydroxy-3-methylglutaryl-CoA) reductase were studied in primary cultures of adult-rat hepatocytes after exposure of the cells to insulin and/or carbohydrates. To determine the contribution of protein synthesis to changes in enzyme activity, the relative rate of synthesis of each enzyme was measured and the amount of translatable mRNA coding for the enzymes was determined by translation in vitro and immunoprecipitation. Addition of insulin to the culture medium increased the activities of acetyl-CoA carboxylase and HMG-CoA reductase by approx. 4- and 3-fold respectively. Although similar increases in the relative rate of synthesis of each protein and template activity were noted, initial increases in the activity of each enzyme occurred before any changes in protein synthesis were observed, suggesting the involvement of post-translational modification of enzyme activity in addition to changes in protein synthesis. The addition of fructose to the culture medium, in the absence of insulin, increased the activity of the carboxylase and the reductase approx. 3-fold, similar to the effects of insulin. However, the effect of fructose was to increase the rate of synthesis and the amount of translatable mRNA coding for acetyl-CoA carboxylase, whereas the increase in the activity of HMG-CoA reductase was not accompanied by any changes in the rate of synthesis or template activity. The effects of fructose could not be mimicked by glucose unless insulin was also present in the culture medium. Similar to observations in vitro, the injection of insulin or the feeding of a high-fructose diet to rats made diabetic by the injection of streptozotocin produced an increase in the activities of acetyl-CoA carboxylase and HMG-CoA reductase, and only the increase in the activity of the carboxylase was accompanied by an increase in the amount of translatable mRNA coding for the enzyme. The results are discussed in terms of the effects of fructose on the synthesis of enzymes involved in lipogenesis.

Formate dehydrogenase molybdenum and tungsten sites--observation by EXAFS of structural differences.

Preliminary EXAFS data has been collected on the molybdenum (K-edge) in C. pasteurianum formate dehydrogenase and the tungsten (LIII-edge) in C. thermoaceticum formate dehydrogenase. In the presence of dithionite, the tungsten enzyme was devoid of W = O bonds, and exhibited average W-(O, N) and W-S bond lengths of 2.13 +/- 0.03 A and 2.39 +/- 0.03 A, respectively. In sharp contrast, the C. pasteurianum molybdenum site has three Mo = O bonds with an average bond length of 1.74 +/- 0.03 A. It is also the first molybdenum enzyme found lacking Mo-S bonds, and does not appear to be redox active in the presence of formate or dithionite. Model compounds WO2(8-hydroxyquinoline)2 = WO2(ox)2, and WO2(8 mercaptoquinoline)2 = WO2(tox)2, were also examined. Respective predicted bond lengths for WO2(ox)2 and WO2(tox)2 were W = O of 1.71, 1.73 A; W-N of 2.31, 2.29 A; W-O or W-S of 1.92 or 2.40 A, with estimated uncertainties of +/- 0.03 A.

Pathway of glycogen synthesis from glucose in hepatocytes maintained in primary culture.

Glycogen synthesis was examined in primary cultures of adult rat hepatocytes that had been isolated from rats following a 24-h fast. Glycogen synthesis was dependent on the concentration of glucose in the culture medium and also required the presence of insulin. The addition of dexamethasone to the culture medium also increased the amount of glycogen synthesis. When the culture medium was supplemented with [U-14C,3-3H]glucose, it was found that approximately 60% of the glucose incorporated into glycogen was not derived from the pool of labeled glucose. In addition, the relative ratio of 3H/14C in the newly synthesized glycogen was approximately 50% of the ratio of the two isotopes in glucose in the culture medium, indicating that the glucose had undergone metabolism prior to its incorporation into glycogen. However, when hepatocytes were isolated from rats that had been fed ad libitum and the synthesis of glycogen from [U-14C,3-3H]glucose was followed, the relative ratio of the two isotopes in glycogen was similar to that measured for glucose in the culture medium, indicating that the glucose was directly incorporated into glycogen without any apparent metabolism. These results indicate that the synthesis of glycogen from glucose may, at least in part, follow an indirect pathway whereby glucose is metabolized prior to incorporation of the carbon into glycogen, but that the pathway followed for the synthesis of glycogen is dependent on the prior metabolic state of the animal.

Effects of biotin upon the intracellular level of cGMP and the activity of glucokinase in cultured rat hepatocytes.

The effects of biotin upon the intracellular level of cGMP and the activity of glucokinase were examined in primary cultures of adult rat hepatocytes. The addition of biotin to the culture medium of hepatocytes increased their content of cGMP 3-fold within 1 h. A 4-fold increase in the activity of glucokinase was observed in response to the addition of the vitamin to the culture medium and the maximal response was observed 6 h following the addition to the medium. These maximum effects were noted when biotin was present in the culture medium at a concentration of 10(-6) M. The induction of glucokinase activity by biotin was preceded by an increase in the intracellular level of cGMP. The addition of 8-bromo-cGMP to the culture medium also increased the activity of glucokinase and its effects were not additive with respect to the effects of biotin. The induction of glucokinase by biotin or the cyclic nucleotide analog was not observed in the absence of insulin. The effects of biotin upon the activity of glucokinase could be mimicked by including glucose in the culture medium. When hexose utilization by the hepatocytes was blocked by the addition to the culture medium of N-acetylglucosamine, the induction of glucokinase by biotin was unaffected, whereas the induction brought about by glucose was not observed. The changes in the activity of the enzyme brought about by biotin or 8-bromo-cGMP was shown to arise as the result of changes in the rate of synthesis of the enzyme. In addition, using an in vitro translation assay and immunoprecipitation, it was found that biotin and 8-bromo-cGMP increased the amount of translatable mRNA coding for the enzyme.

Gender identity and its implications for the concepts of masculinity and femininity.

In this chapter, I have suggested that although the terms masculine and feminine and masculinity and femininity have rarely been defined, they appear to have two types of meaning both for psychologists and for the community at large. First, masculine and feminine have an empirical meaning, being used as labels to identify specific objects, events, or qualities that in a given culture are perceived as more closely associated with males or with females. Second, these adjectives and, even more exclusively the nouns masculinity and femininity, are used as theoretical constructs that refer to a fundamental property or aspect of the individual's self-concept that is not directly observable. Masculinity and femininity in this second sense are conceived as bipolar opposites, almost all men having a firm sense of their psychological masculinity and almost all women having a similar sense of their femininity. The implicit assumptions on which conventional theories of masculinity-femininity are predicated imply that all gender-related phenomena contribute to a bipolar femininity-masculinity factor so that assessment of an individual's masculine and feminine qualities (in the empirical sense of these terms) can be used to infer his or her position on the hypothetical masculinity-femininity continuum. Constructs such as sex-role identification and sex-role orientation are based on the same assumptions. More recently it as been proposed that masculine and feminine qualities and their accompanying self-images of masculinity and femininity constitute instead two separate, statistically independent dimensions. However, most investigators nominally advancing this two-factor model and tying the measurement of masculinity and femininity to instruments containing separate scales of masculine and feminine attributes have in fact employed unidimensional bipolar models, based on such concepts as sex-role identification, sex typing, or gender schema. The empirical data, however, support neither the one-factor nor the two-factor model of gender-differentiating phenomena, suggesting instead that they are multidimensional. To the extent that the concepts of masculinity-femininity (and other similar unidimensional constructs) or of masculinity and femininity are intended to represent the structure of gender-relevant characteristics, these constructs lack validity. I proposed, however, that masculinity and femininity, as they refer to an individual's self-concept, be retained and reconceptualized as gender identity: a basic phenomenological sense of one's maleness or femaleness that parallels awareness and acceptance of one's biological sex and is established early in life.(ABSTRACT TRUNCATED AT 400 WORDS)

Siderophores Produced by Nitrogen-Fixing Azotobacter vinelandii OP in Iron-Limited Continuous Culture.

Azotobacter vinelandii requires a high complement of iron and an efficient iron acquisition system to support nitrogen fixation. To circumvent problems inherent in batch culture trace metal studies, continuous cultures were used to measure the response of A. vinelandii to iron stress. Iron was found to be growth limiting for nitrogen-fixing A. vinelandii at a concentration as high as 12.5 muM; iron was growth sufficient at 25 muM. Iron-stressed A. vinelandii in continuous culture formed 2,3-hydroxybenzoic acid (DHB), 2-N,6-N-di-(2,3-dihydroxybenzoyl)-l-lysine (DHBL), and a chromophoric yellow-green fluorescent peptide (YGFP). At a fixed dilution rate of 0.1 h, steady-state growth occurred at growth-limiting iron concentrations. DHB and DHBL were quantitatively measured during iron-limited steady states and iron-sufficient states by Arnow colorimetric assays. YGFP was determined by absorbance measurements taken at 380 nm, and the concentration was calculated from the reported specific absorption coefficient. Biomass increased and DHBL, DHB, and YGFP concentrations decreased as the concentration of growth-limiting iron was increased in the culture vessel and medium reservoirs. DHBL was the major siderophore and YGFP was the minor siderophore species produced during iron-limited equilibrium growth. A low level of DHB and YGFP, but no DHBL, was formed under iron-sufficient conditions. These results provide further physiological evidence that DHB, YGFP, and especially DHBL may function as siderophores in nitrogen-fixing A. vinelandii.

Levels of translatable mRNA coding for rat liver glucokinase.

Changes in the level of translatable mRNA coding for glucokinase under different physiological conditions were determined using a reticulocyte lysate translation system and immunoprecipitation. Poly(A+) RNA isolated from livers of rats fed a high carbohydrate diet displayed a 10-fold increase in glucokinase template activity when compared to starved rats. Livers from streptozotocin-induced diabetic rats had only 9% of the glucokinase template activity displayed by controls. Administration of insulin to diabetic rats produced an increase in the level of mRNA coding for glucokinase within 20 min and reached a maximum 13-fold increase 1 h following insulin treatment. Under all experimental conditions examined, changes in the level of glucokinase mRNA were accompanied by similar changes in direction and magnitude of enzyme activity and the relative rate of synthesis of the enzyme in vivo. In addition, the developmental appearance of glucokinase activity at the 16th day following birth was accompanied by a corresponding increase in the amount of glucokinase mRNA. Thus, it appears that dietary, hormonal, and developmental changes in the activity of glucokinase arise as the result of changes in the amount of functional mRNA coding for the enzyme.

A rapid and sensitive paper electrophoresis assay for the detection of microbial siderophores elicited in solid-plating culture.

A rapid and sensitive assay for the detection of microbial siderophores (iron-binding compounds) is described. Nine representative fungal and bacterial cultures including Ustilago sphaerogena, Penicillium sp., Fusarium roseum, Rhodotorula pilimanae, Bacillus subtilis W 23, Bacillus subtilis W 168, Bacillus megaterium, Azotobacter vinelandii OP, and Escherichia coli B, were nutritionally stressed for iron by sequential transfers on iron-deficient solid-plating media. In response to Fe-stress conditions, the microorganisms excreted siderophore compounds into the extracellular solid culture medium. The solid agar matrix effectively concentrated and restricted the migration of the siderophore compounds to the region immediately adjacent to colonial growth. Agar-block samples from this region were removed and placed at the origin of an electrophoresis paper strip. The resultant absorbed material from the agar-block sample was subjected to high-voltage paper electrophoresis which separated the siderophore compounds by size and molecular net charge. Phenolic acid ("catechol")-type siderophores were detected by fluorescence under uv light. Hydroxamic acid-type siderophores were visualized by spraying the electrophoretogram with ferric iron solution.