Dietary methionine is involved in the etiology of neural tube defect-affected pregnancies in humans.

Research has provided evidence of the role of multivitamin supplementation in the prevention of neural tube defects (NTD). Failure of the neural tube to close is one of the most frequent and severe human developmental defects. The etiology of NTD is complex, encompassing genetic, dietary and environmental factors. The purpose of this study was to explore the relationship between maternal dietary intake of methionine and the risk of having a NTD-affected pregnancy. We hypothesized that women with high maternal dietary methionine intake were at a decreased risk for a NTD. Combinations of methionine, folate and vitamin B-12 intakes and NTD risk were also examined. Data from a 5-y, population-based, case-control study of 170 NTD-affected pregnancies and 269 controls were provided by the South Carolina NTD Surveillance, Prevention, and Research Project. There was a 30-55% lower NTD risk among women whose average daily dietary intake of methionine was greater than the lowest quartile of intake (>1580 mg/d). The odds ratios associated with the three quartiles of methionine intake > 1580 mg/d after adjusting for energy, race and body mass index were 0.72 (P < 0.07), 0.68 (P < 0.07) and 0.45 (P < 0.06), respectively. These findings indicate that a reduction in the risk of having a NTD-affected pregnancy is associated with maternal dietary intake of methionine (3 mo pre- to 3 mo postconception). This finding is consistent with the hypothesis that methionine plays a role in the etiology of NTD and suggests the need for further research in the area of maternal diet and pregnancy.

Identification of the factors associated with compliance to therapeutic diets in older adults with end stage renal disease.

OBJECTIVE: To identify theory based factors pertinent to compliance with therapeutic diets. DESIGN: A paper and pencil survey was read to volunteer hemodialysis patients in outpatient dialysis clinics. SUBJECTS: A convenience sample of 276 hemodialysis patients aged 50 years and older who agreed to be interviewed during treatment. STATISTICAL ANALYSIS: Descriptive statistics were used to report responses to all survey questions. The Fisher exact test was used to test associations between the dependent variable, dietary compliance, and independent variables, which included knowledge, perceived severity of illness, attitudes toward compliance, environmental factors, perceived barriers, self-efficacy, and perceived health benefits. Principal Components Analysis determined final scale items. Logistic regression was used to develop a model of independent variables profiling the compliant patient. RESULTS: Subjects were more likely to be compliant if they indicated favorable attitudes toward compliance (P =.0076), a supportive environment (P =.0107), and knowledge about their diet (P =.0014). A logistic regression model of compliance indicated that subjects who followed their special diets were more likely to have higher knowledge (odds ratio [OR] = 1.092, 95% CI = 1.006, 1.186), perceived fewer barriers (OR = 1.094, 95% CI = 0.841, 1.226), being white race (OR = 0.710, 95% CI = 0.399, 1.263), and having gout (OR = 9.349, 95% CI = 1.139, 76.714). APPLICATION: Health professionals should apply these findings in providing dietary education focused on improving not just knowledge, but attitudes and family support. Nutrition education and health promotion applications geared to non-white populations could be particularly important as tools to improve dietary compliance.

Insertion of a telomere repeat sequence into a mammalian gene causes chromosome instability.

Telomere repeat sequences cap the ends of eucaryotic chromosomes and help stabilize them. At interstitial sites, however, they may destabilize chromosomes, as suggested by cytogenetic studies in mammalian cells that correlate interstitial telomere sequence with sites of spontaneous and radiation-induced chromosome rearrangements. In no instance is the length, purity, or orientation of the telomere repeats at these potentially destabilizing interstitial sites known. To determine the effects of a defined interstitial telomere sequence on chromosome instability, as well as other aspects of DNA metabolism, we deposited 800 bp of the functional vertebrate telomere repeat, TTAGGG, in two orientations in the second intron of the adenosine phosphoribosyltransferase (APRT) gene in Chinese hamster ovary cells. In one orientation, the deposited telomere sequence did not interfere with expression of the APRT gene, whereas in the other it reduced mRNA levels slightly. The telomere sequence did not induce chromosome truncation and the seeding of a new telomere at a frequency above the limits of detection. Similarly, the telomere sequence did not alter the rate or distribution of homologous recombination events. The interstitial telomere repeat sequence in both orientations, however, dramatically increased gene rearrangements some 30-fold. Analysis of individual rearrangements confirmed the involvement of the telomere sequence. These studies define the telomere repeat sequence as a destabilizing element in the interior of chromosomes in mammalian cells.

Racial and gender differences in weight status and dietary practices among college students.

A questionnaire was used to assess nutritional intake, weight status, and dietary practices among 630 U.S. college students. Body mass index (BMI) was calculated using self-reported heights and weights, and nutritional status was assessed via 24-hour recall. Sixty-four percent of the students had acceptable BMI levels (between 19 and 25); 16% of African-American females and 15% of African-American males had BMIs indicating obesity (30 or above). Approximately 18% of the students consumed 5 servings per day of fruits and vegetables, 7% consumed 6 or more grain products, and 53% consumed 2 or more dairy products. Twenty-seven percent reported never/rarely eating fast foods. Recommendations are presented for the development of culturally appropriate health education/promotion programs in order to help college students meet Healthy People 2010 objectives.

Body dissatisfaction among White and African American male and female college students.

Body size perception has been shown to be highly influenced by cultural factors including race. This study assessed body size perceptions of a convenience sample of college students (N=630). Included in a paper-and-pencil survey were current height and weight (body mass index (BMI)=wt [kg]/ht(2) [m]), perceived BMI, desired MI and perceptions of BMIs desired by others. Also assessed were perceptions of underweight, acceptable weight and overweight/obesity. African American females were found to have a higher current BMI than Whites (P< or =.001), higher desired BMI (P< or =.001) and higher BMI perceived to be desired by others (P< or =.001). African American and White males did not differ on any of these measures. Most (83%) underweight (BMI<19) African American females perceived themselves as underweight while only about one-half of underweight (56%) White females perceived themselves as underweight. Almost half (43%) of White females and about a fourth (27%) of African American females of acceptable BMI range (BMI=19-25) desired to be in the underweight range. Of those who were overweight (BMI=25-30), 20% of the Whites and only 3.0% of the African Americans chose an underweight silhouette as being desired. While African Americans and White males tended to have similar perceptions that there remains sociocultural influences in African American females regarding acceptance of a large body size.

A study of the attribution style, self-efficacy, and dietary restraint in female binge and non-binge eaters.

The purpose of this study was to identify the role that attribution style and self-efficacy expectations have in overweight binge and non-binge eaters. The subjects were women (n=210) enrolled for weight control treatment, who completed a questionnaire to assess attribution style and self efficacy expectations. They were categorized into three binge eating disorder (BED) groups: non-BED, borderline BED and BED. The results of the ANOVA analysis indicated that the borderline and BED groups were significantly similar in terms of all measures of attribution and self-efficacy; and logistic regression analysis that the odds of being borderline BED or BED were greater if an individual had internal attributions, and more likely in the presence of diminished self-efficacy expectations. The subjects with low levels of eating self-efficacy and internal, global, and uncontrollable attributions were also more likely to have borderline BED and BED. The implications of the borderline BED category are discussed in relationship to the DSM-IV BED diagnosis.

Role of the nucleotide excision repair gene ERCC1 in formation of recombination-dependent rearrangements in mammalian cells.

Spontaneous recombination between direct repeats at the adenine phosphoribosyltransferase (APRT) locus in ERCC1-deficient cells generates a high frequency of rearrangements that are dependent on the process of homologous recombination, suggesting that rearrangements are formed by misprocessing of recombination intermediates. Given the specificity of the structure-specific Ercc1/Xpf endonuclease, two potential recombination intermediates are substrates for misprocessing in ERCC1(-) cells: heteroduplex loops and heteroduplex intermediates with non-homologous 3' tails. To investigate the roles of each, we constructed repeats that would yield no heteroduplex loops during spontaneous recombination or that would yield two non-homologous 3' tails after treatment with the rare-cutting endonuclease I-SCE:I. Our results indicate that misprocessing of heteroduplex loops is not the major source of recombination-dependent rearrangements in ERCC1-deficient cells. Our results also suggest that the Ercc1/Xpf endonuclease is required for efficient removal of non-homologous 3' tails, like its Rad1/Rad10 counterpart in yeast. Thus, it is likely that misprocessing of non-homologous 3' tails is the primary source of recombination-dependent rearrangements in mammalian cells. We also find an unexpected effect of ERCC1 deficiency on I-SCE:I-stimulated rearrangements, which are not dependent on homologous recombination, suggesting that the ERCC1 gene product may play a role in generating the rearrangements that arise after I-SCE:I-induced double-strand breaks.

Black and White women's weight-related attitudes and parental criticism of their childhood appearance.

Black (27%) and White (73%) women (n = 215) completed a survey assessing weight concern, ideal body size beliefs, body dissatisfaction, attitudes toward overweight body size, and parental criticism of their childhood appearance. Sixty-four percent of the women reported they were currently trying to lose weight and 63% desired a body size thinner than their own. High weight concern and negative attitudes toward overweight persons were reported, respectively, by 45% and 17%, of the women. The only significant difference found by race was weight concern as White women rated this significantly higher than Black women. No significant frequencies of choice were associated with the women's socioeconomic level. Self-reported ratings of weight concern were significant and positively associated with those for body dissatisfaction, negative attitudes toward overweight persons, negative attitudes toward one's own overweight, and criticism of childhood appearance by mothers or fathers.

A study of body weight concerns and weight control practices of 4th and 7th grade adolescents.

OBJECTIVE: The purpose of this study was to assess grade, race, socioeconomic status and gender differences in perceptions of body size, weight concerns, and weight control practices between 4th and 7th grade students in South Carolina. DESIGN: Two random samples, consisting of a total of 1,597 children (53.1% white, 51.97% female, 44.9% 4th graders) participated in two questionnaire surveys. Both surveys included a series of seven female and seven male body size drawings, body image and weight concern questions, and questions pertaining to weight control practices. Responses to the questionnaire were analyzed using chi-square analysis and the General Linear Model. RESULTS: Using socioeconomic status (SES), race, gender, and grade as independent variables, differences in ideal adult body size, opposite gender ideal adult body size, weight concerns, perceptions of family/peer weight concerns, perceptions of own body size and weight control practices were studied. Analyses revealed that 4th grade males select a larger ideal adult body size and opposite gender ideal adult body size when compared to 7th grade males (p < 0.0001 and p = 0.0078, respectively). Fourth grade females indicated less personal concern about their weight than 7th grade females (p = 0.0009). Fourth graders also perceived less family/peer concern about weight than 7th graders (p = 0.0027) and 7th graders described themselves as being more overweight than 4th graders (p = 0.0039). Blacks selected a significantly larger body size than white children for ideal adult (p = 0.0287) and ideal opposite gender adult body size (p < 0.0001 for males, p = 0.0030 for females). Blacks also perceived less personal and family/peer concern about weight when compared to whites (p = 0.0083). More whites reported that they were trying to lose weight, as compared to blacks (p = 0.0010). Males also selected significantly larger body size silhouettes than females for ideal adult body size (p = 0.0012). Males expressed less personal concern about weight (p < 0.0001), perceived less family/peer concern about weight (p < 0.0001), and were less likely than females to be engaged in weight loss (p < 0.0001). Females in the high SES category selected a significantly smaller ideal male adult body size than females in the low SES group (p = 0.0124) and more females in the high SES category were trying to lose weight when compared to females in the low SES group (p = 0.0055). CONCLUSION: This study indicates that early in a child's sociocultural development, grade level, gender, race, and SES are influential in the perception of ideal adult body size and opposite gender ideal adult body size. These factors are also influential in determining concerns about weight and weight control practices. The findings of this study support the need to begin health and wellness education efforts early in childhood while taking into account racial, gender, age, and SES disparities. This knowledge can also be useful in targeting interventions for both obesity and eating disorders.

Production of chromatid breaks by single dsb: evidence supporting the signal model.

PURPOSE: The signal model proposes that all chromatid breaks arise from a single DNA double strand break (dsb) via a recombinational exchange mechanism. Here the prediction that chromatid breaks arise from a single dsb is tested. METHOD: The genetically engineered Chinese hamster cell line GS19-43 containing a unique yeast I-SceI recognition site was treated with I-SceI endonuclease (Meganuclease) in the presence of the porating agent streptolysin O. Chromatid breaks were scored at 4h, chromosome breaks at 18 and 22h following treatment (cells used for a 4h fixation were prelabelled with BrdU over two cell-cycles). Positive controls were treated with the restriction endonuclease Pst 1. RESULTS: I-SceI endonuclease produced chromatid breaks and at higher enzyme concentrations isochromatid breaks but no chromatid interchanges. About 16% of the chromatid breaks had a 'colour-switch' between the sister-chromatids at the site of breakage, as revealed by FPG staining. At the longer fixation times (18 and 22 h) chromosome breaks were observed, but again no interchanges were seen. Chromatid and chromosome breaks always appeared on the same chromosome. CONCLUSIONS: The production of chromatid breaks from a single dsb fulfils the prediction of the signal model. Moreover, the production of colour-switch breaks at a similar frequency to that for ionizing radiation indicates that chromatid breaks are produced via recombinational exchanges, a significant proportion of which occurs between sister chromatids. The majority is intrachromatid, not involving strand-switches. The absence of interchromosomal exchanges at all fixation times indicates a requirement of two dsb in two different chromosomes for their formation.

Expanding the criteria for defining success when evaluating weight loss intervention programs.

In order to evaluate outcomes among former participants in a residential weight loss program, attendees were surveyed from 1 to 5 years post-intervention. A total of 187 respondents were studied for weight changes and behavioral practices. Diet practices were assessed by number of servings per day using the Food Guide Pyramid recommendations as a guideline for indicating fruit and vegetable intake. Exercise behaviors were measured in frequency, duration, and intensity, and a weighted score was computed to obtain units for describing physical activity. Maintaining a 10% weight loss from the program entry weight, consuming five or more servings per day of fruits and/or vegetables (5-a-day) and maintaining an "active" level of physical activity were included in criteria for describing intervention success. Those meeting two of the three criteria were categorized as "successful," which included 35.8% of the study population. Because each of these behaviors (5-a-day, active lifestyle, and modest weight loss maintenance) result in independent risk reduction, it is recommended that future weight loss intervention evaluations expand the criteria for describing successful impacts and outcomes to include not only weight maintenance, but also physical activity and diet compliance behaviors.

Measurements of body image in clinical weight loss participants with and without binge-eating traits.

This study measured body image disturbances of individuals in a residential weight loss program who were identified as having binge-eating disorder (BED) traits. The study population (N=97) was a convenience sample of 74 men (76%, mean age=51.0) and 23 women (24%, mean age=49.6) in the program who completed the Eating Questionnaire-Revised (EQ-R), the Attitudes About Weight and Dieting (AAWD), the Physical Appearance State and Trait Anxiety Scale (PASTAS): State Version, and the Contour Drawing Rating Scale (CDR). Fifty-five individuals reported having binge traits (57%) while 42 (43%) had no binge traits. Individuals with the binge traits had a significantly higher BMI than nonbinge trait individuals (P=.008). The binge trait group scored higher on the total AAWD (P=.004), the AAWD factor "Fear of Fat" (P=.002), the total PASTA (P=.001), and the PASTA factor "Weight" (P=.001) than the nonbinge trait group. Logistic regression analysis indicated that the odds of having a binge trait were 1.44 times more likely for a person at a given score on the PASTA subscale Weight vs. a person at a score of 5 units less. Feelings of being unable to control eating among individuals seeking weight control is associated with several characteristics related to body image. Individuals showing greater concern about weight and dieting and specifically greater fears of becoming fat were more likely to have a problem with binge eating than those without these concerns. The results of this study suggest that a negative body image is an important factor to consider when treating individuals indicating binge-eating traits.

Self-efficacy in overweight individuals with binge eating disorder.

OBJECTIVE: To evaluate the relationship between self-efficacy judgments in obese individuals with binge eating disorder, "borderline" binge eating disorder, and no binge eating problems. RESEARCH METHODS AND PROCEDURES: Before participation in a residential weight management program, 79 male and female subjects were administered the Weight Efficacy Lifestyle Questionnaire (WEL) and the Binge Eating Scale (BES). Based on DSM-IV diagnostic questions, subjects were categorized as BED, Borderline BED, or non-BED. RESULTS: Krusal-Wallace Rank-Order analysis of variance revealed significant negative associations between binge eating and total WEL scores as well as the subscales of Negative Emotions, Social Pressure, Physical Discomfort, and Positive Activities. Differences were significant between the BED and the Borderline BED groups with the exception of the Social Pressure scale and the Total WEL scores. BED diagnosis as well as severity of binge eating were strongly associated with low self-efficacy ratings. DISCUSSION: These results indicate that obese individuals with binge eating disorder demonstrate lower self-efficacy than those without this condition and that self-efficacy is related to the severity of binge eating.

Gender differences among those exhibiting characteristics of binge eating disorder.

One hundred and eighty-seven former residential weight control participants exhibiting binge eating traits were assessed for gender differences regarding demographics, diet, exercise, weight control techniques, behavior modification techniques and binge eating characteristics. Data were gathered using a 68-item paper pencil questionnaire. Results indicate that there were no significant differences between males and females regarding demographic variables, and the number and types of weight control programs tried since leaving the residential program. Significant differences did exist between males and females in the number of times they had started dieting in the past year. No significant differences were observed among males and females regarding severity, binge emotions and compensatory behaviors. Statistically significant differences did exist regarding post-binge emotions. Results from this study suggest that males and females differ in regard to the diet/binge cycle and additionally, males appear to have a different or less emotional response subsequent to a binge.

Binge eating and its relationship to multiple weight control program attendance and alternative methods of weight control.

Binge eating and its relationship to multiple program attendance and use of alternative methods of weight control was assessed among 187 former residential weight control participants. Subjects completed a 68-item questionnaire assessing weight control techniques, exercise behaviors, behavior modification techniques, binge eating, and dieting behaviors. Results indicate that respondents who attended other programs after leaving the residential weight control program had significantly higher scores on monitoring food amounts, binge eating characteristics, and post-binge emotions. Similarly, respondents who tried alternative methods of weight control after leaving the program had significantly higher scores on the variables binge eating severity, feelings during a binge, and post-binge emotions. These findings support the binge/diet/obesity cycle and suggest that obese persons with binge problems should discontinue dieting and be directed toward appropriate intervention strategies. Furthermore, policy aimed at screening individuals for binge eating traits prior to weight control program participation is needed.

Recombination-dependent deletion formation in mammalian cells deficient in the nucleotide excision repair gene ERCC1.

Nucleotide excision repair proteins have been implicated in genetic recombination by experiments in Saccharomyces cerevisiae and Drosophila melanogaster, but their role, if any, in mammalian cells is undefined. To investigate the role of the nucleotide excision repair gene ERCC1, the hamster homologue to the S. cerevisiae RADIO gene, we disabled the gene by targeted knockout. Partial tandem duplications of the adenine phosphoribosyltransferase (APRT) gene then were constructed at the endogenous APRT locus in ERCC1- and ERCC1+ cells. To detect the full spectrum of gene-altering events, we used a loss-of-function assay in which the parental APRT+ tandem duplication could give rise to APRT- cells by homologous recombination, gene rearrangement, or point mutation. Measurement of rates and analysis of individual APRT- products indicated that gene rearrangements (principally deletions) were increased at least 50-fold, whereas homologous recombination was affected little. The formation of deletions is not caused by a general effect of the ERCC1 deficiency on gene stability, because ERCC1- cell lines with a single wild-type copy of the APRT gene yielded no increase in deletions. Thus, deletion formation is dependent on the tandem duplication, and presumably the process of homologous recombination. Recombination-dependent deletion formation in ERCC1- cells is supported by a significant decrease in a particular class of crossover products that are thought to arise by repair of a heteroduplex intermediate in recombination. We suggest that the ERCC1 gene product in mammalian cells is involved in the processing of heteroduplex intermediates in recombination and that the misprocessed intermediates in ERCC1- cells are repaired by illegitimate recombination.

A methodology for optimally designing console panels for use by a single operator.

A seven-step methodology is presented to determine a dimensionally correct optimal layout of a console panel for a single operator. This methodology integrates the steps in the layout design process and uses a mathematical optimization model from facility design to obtain the optimal panel layout. A major difference in this methodology from previous work is that the mathematical optimization model incorporates factors that are only partially included in previous mathematical models. In addition, it includes the areas of the panel components as a new factor. This methodology is illustrated by the design of a nuclear power plant console panel.

The impact of a required college health and physical education course on the health status of alumni.

The impact of a required college health and physical education course on selected health knowledge, attitudes, and behaviors of alumni was evaluated. The design was a cross-sectional study (mail out/mail back survey) using a stratified random sample of 2,000 college alumni. The overall response rate was 50%. Results were analyzed by college of graduation (college with a required health/physical education course versus no required course). Alumni who took the course were more likely to know their blood pressure, blood cholesterol, and recommended dietary fat intake than the comparison group were. They also reported that the course positively influenced their attitudes toward exercise, eating, and smoking They were more likely to engage in aerobic exercise and less likely to smoke; and they had lower intakes of dietary fat, cholesterol, and sodium. The results suggested that a required college course enhanced selected health-related knowledge, attitudes, and behaviors of alumni.

Black-white differences in body size perceptions and weight management practices among adolescent females.

OBJECTIVE: This study compares body size perceptions and weight management practices of black and white adolescent females. DESIGN: Subjects were selected through a statewide, three-stage sampling procedure designed to provide a sample statistically representative of high school students in South Carolina. SUBJECTS: Participants included black (n = 1824) and white (n = 2256) females, 14-18 years of age, enrolled in South Carolina public high schools. METHODS: Respondents were asked to assess their perceived body size as overweight, underweight, or about right. Self-reported weight management practices included dieting (reducing caloric intake), exercise, and other methods (including diet pills and vomiting). Chisquare analysis was used to assess the differences in body size perception and weight management behaviors. Polychotomous logistic regression was performed to examine association while controlling for socioeconomic status. RESULTS: Forty-one percent of the white adolescents and 29% of the black adolescents perceive themselves as overweight (p < 0.005). In the week prior to the survey, 28% of the white adolescents and 13% of the black adolescents reported dieting 34% of the while versus 23% of the black adolescents reported exercising to lose weight; and 45% of the white and 16% of the black students reported both dieting and exercising. Polychotomous logistic regression analysis showed that white adolescent girls were almost twice as likely to perceive themselves as overweight as black adolescent girls. The white students had 6.04 [95% confidence interval (CI), 1.77, 20.67] times the odds of using pills and vomiting and 3.76 (95% CI, 2.99, 4.72) times the odds of engaging in dieting and exercising as methods of weight management compared to the black students. CONCLUSIONS: These findings suggest that white adolescents are more likely to perceive themselves as overweight than black adolescents and are more likely to engage in unhealthy weight management practices than black adolescents.

Ideal body size beliefs and weight concerns of fourth-grade children.

OBJECTIVE: The purpose of this study was to assess racial and gender differences in perceptions of ideal body size among White and Black fourth-grade children. METHOD: A random sample of 817 children (51.4% female, 51.8% White, and mean age 9 years) participated in a body image and weight concern survey. RESULTS: Using socioeconomic status (SES), race, and gender as independent variables, Black children selected significantly heavier ideal sizes than White children for self, male child, female child, adult male, and adult female. Although almost one half (46%) of Black females wanted to be thinner than their current size, their body size selections were significantly larger than those of White females. Black and White males differed only in the selections of ideal-female child and adult sizes. Cross-gender comparisons indicated females and Whites experience more body dissatisfaction and weight concern than males and Blacks. DISCUSSION: Our study indicates that early in the sociocultural development of children, gender, race, and SES are influential factors in selecting ideal body size and determining body satisfaction.