Chronic γ-secretase inhibition reduces amyloid plaque-associated instability of pre- and postsynaptic structures.

The loss of synapses is a strong histological correlate of the cognitive decline in Alzheimer's disease (AD). Amyloid ß-peptide (Aß), a cleavage product of the amyloid precursor protein (APP), exerts detrimental effects on synapses, a process thought to be causally related to the cognitive deficits in AD. Here, we used in vivo two-photon microscopy to characterize the dynamics of axonal boutons and dendritic spines in APP/Presenilin 1 (APP(swe)/PS1(L166P))-green fluorescent protein (GFP) transgenic mice. Time-lapse imaging over 4 weeks revealed a pronounced, concerted instability of pre- and postsynaptic structures within the vicinity of amyloid plaques. Treatment with a novel sulfonamide-type γ-secretase inhibitor (GSI) attenuated the formation and growth of new plaques and, most importantly, led to a normalization of the enhanced dynamics of synaptic structures close to plaques. GSI treatment did neither affect spines and boutons distant from plaques in amyloid precursor protein/presenilin 1-GFP (APPPS1-GFP) nor those in GFP-control mice, suggesting no obvious neuropathological side effects of the drug.

Dieting among Thai adolescents: having friends who diet and pressure to diet.

The purpose of this study was to assess dieting behavior, the number of friends who diet, and number of friends who pressure to go on a diet among a sample of 2,519 Thai adolescents. More than half of the girls (52.2%) and over one-fourth of boys (28.0%) reported going on a diet in the past 30 days. Dieting among friends was very common with only 14.2% of girls and 34.3% of boys saying none of their friends dieted. Results also showed significant associations between 1) number of friends who diet and 2) number of friends who pressure to diet with dieting behavior, body mass index (BMI), weight satisfaction, perceived body fatness, effort to look like people in the media, and frequency of thinking about wanting to be thinner in girls. In addition, several of these associations for boys were significant. The role of BMI in these relationships was also explored.

Occupational physical activity as an indicator of health and fitness.

Recent government guidelines suggest that simply increasing physical activity, regardless of mode, leads to improved health profiles. This study examined the relationship between amount of work-related physical activity of United States Forest Service (USFS) workers and 12 indicators of health and fitness. Subjects were 110 USFS workers recruited from 8 separate USFS ranger stations in the Pacific Northwest. The associations between work-related physical activity and indicators of health and fitness indicated the 63 workers who were physically active on the job displayed better overall health and fitness patterns as evidenced by higher aerobic capacity, lower body fat, and greater muscular flexibility than their 47 inactive peers.

Relationship between television viewing frequency and scores on shyness among Philippine high school students.

The association between frequency of watching TV and scores on a measure of shyness was estimated for a sample of 3,307 Philippine high school students (1,267 boys and 1,819 girls). Students who watched more than 5 hours of TV a day scored significantly higher on shyness than students who watch less TV.

Psychosocial, behavioral, and biometric characteristics of stages of exercise adoption.

This study incorporates the Stages of Change model to examine the relationship between the stages of exercise adoption and indicators of health and fitness. Subjects were 198 United States Forest Service (USFS) workers recruited from 8 USFS ranger stations in the Pacific Northwest. Analysis indicated that those subjects in Action and Maintenance stages of exercise adoption differed significantly from those in Preparation and Precontemplation/Contemplation stages on a variety of indicators of both health and fitness. Also, interesting differences were noted among the physically inactive stages, e.g., Preparation stage subjects showed lower triglycerides, systolic blood pressure, and higher HDL cholesterol compared with subjects in the Precontemplation/Contemplation stage. Progressing to the Preparation stage, where the individual remains inactive but is aware of the problem and has begun to make small changes, is associated with a differing (more positive) health profile in this study compared to those in the Precontemplation/Contemplation stage. These results imply that simply advancing in stage can have a variety of health benefits.

College students' distorted perception of the prevalence of smoking.

Estimations of the prevalence of daily smoking of cigarettes by men and women on a college campus were obtained from 775 college students. Estimations greatly exceeded the percent of students who personally reported smoking cigarettes daily.

Gender and living alone as determinants of fruit and vegetable consumption among the elderly living at home in urban Nottingham.

Consumption of fruits and vegetables by a sample of 369 elderly people living in Nottingham, England, was analysed in relation to whether or not they were eating five portions a day. Living status was only of significance to men who, if single, consumed 2.66 portions of fruits and vegetables per day compared with an overall mean of 4.1. The salient question is therefore not "Are you living alone?" but " s there a woman in the household?". Those respondents who were older and less educated ate less vegetables and those respondents who had a lower income or social grade ate less fruit. Men were less likely to be able to cook a range of meals, to have had a job that involved cooking or to watch cookery programmes on television. Single men were more likely than single women to say that eating food that was easy to cook and prepare was an important influence on their food choice. Single women on the other hand were more influenced by body image. Finding foods that were the right portion size and easy to open, prepare and cook was more important to single men than married men, as was the amount of money left after paying the bills.

Food safety knowledge and practice among elderly people living at home.

OBJECTIVE: To assess the food storage knowledge and practice of elderly people living at home. METHODS: Three phase survey data collection: face to face interviews; dietary diaries with a food frequency questionnaire; and follow up interviews. SETTING: Urban Nottingham. PARTICIPANTS: 809 elderly people (aged 65+) randomly selected from general practitioner lists. MAIN OUTCOME MEASURES: Respondent's refrigerator temperature; knowledge of freezer star rating; understanding of "use by" and "sell by" dates; reported ability to read food product safety labels. RESULTS: From a weighted total of 645 refrigerators measured, 451 (70%) were too warm for the safe storage of food (> or = 6 degrees Celsius). Only 41% of respondents (n = 279) knew the star rating of their freezer. Within a smaller sub-sample knowledge of the "use by" and "sell by" dates was good, but 45% of these respondents reported difficulty reading food labels. The storage of foods at inappropriate temperatures was not independent of socioeconomic or demographic status, and tended to be more likely among the poorer and those not living alone. CONCLUSIONS: Food storage practices among the majority of elderly people interviewed in this study do not meet recommended safety standards to minimise the risk of food poisoning.

Fruit and vegetable consumption in later life.

OBJECTIVE: to assess levels of fruit and vegetable consumption in elderly people, and to examine the socio-economic, physical and psychological factors which influence this consumption. METHODS: a three-phase survey: face to face interviews; self-completed dietary diaries with a food frequency questionnaire; and follow-up face-to-face interviews. PARTICIPANTS: 445 elderly people (aged 65+) randomly selected from general practitioner lists in urban Nottingham and rural Nottinghamshire, Lincolnshire and Leicestershire. RESULTS: the recommended target of five portions of fruit and vegetables a day was achieved by less than half the respondents: 37% of those living in the urban area and 51% of those living in the rural area. Low fruit and vegetable consumption was particularly associated with being male, smoking and having low levels of social engagement. CONCLUSIONS: most elderly people consume less than the recommended levels of fruit and vegetables. Health programmes promoting fruit and vegetable consumption may not be successfully reaching elderly people and need to target those particularly at risk of low consumption.

Weapon-carrying and youth violence.

Weapons, and firearms in particular, are widely available in the United States and are at the heart of youth violence. Many schools and communities throughout the nation have identified weapon-carrying among youth as a substantial health, educational, and social problem. In fact, one of the national health objectives for the year 2000 is to substantially reduce the incidence of weapon-carrying among adolescents. This paper reviews the prevalence of weapon-carrying by youth, reasons they carry weapons, ways that firearms are obtained, firearms and violence (especially youth violence), and the controlling of weapons in schools.

Shyness and loneliness: relationship to the exercise frequency of college students.

The purpose of the current study was to estimate the relationship between exercise frequency and measures of shyness and loneliness in a sample of 882 college students. Analysis provided evidence that higher shyness and loneliness scores were associated with not exercising and infrequent exercising. Also, subjects who exercise 7 times a week scored significantly lower than the other exercise-frequency groups. Analysis of covariance, controlling for possible confounding variables, gives further support.

Psychosocial discomfort and exercise frequency: an epidemiological study of adolescents.

This study sought to determine the extent to which adolescents (N = 1,297) who report different levels of physical exercise vary with respect to selected indicators of psychosocial discomfort. Results indicated that those who exercise infrequently suffer more from loneliness, shyness, and hopelessness than do adolescents who exercise more frequently. The potential confounding effects of gender, grade level, perceived attractiveness, body mass, and weight satisfaction were statistically controlled. Potential explanations for the observed relationships between frequency of exercise and psychosocial discomfort and implications for fitness, recreation, and health professionals are presented.

Variance in substance use between rural black and white Mississippi high school students.

The purpose of this study was to determine the extent to which the use of substances varies between black and white students in a sample of primarily rural Mississippi adolescents. It was found that black adolescent males were significantly less likely than white adolescent males to drink alcohol, get drunk, smoke cigarettes, use smokeless tobacco, hallucinogens, and sedatives. Black adolescent females were significantly less likely than white adolescent females to drink alcohol, get drunk, smoke cigarettes, and use marijuana. Differences in proportions of black and white females were more pronounced than differences between black and white males. Possible reasons for these differences are explored.

Co-occurrence of substance use and loneliness as a risk factor for adolescent hopelessness.

This research among a sample of 1,915 Mississippi adolescents investigated whether lonely adolescents who use illicit substances were at increased risk of hopelessness. Relative risk of scoring within the severe hopelessness range was 6.9 for non-substance users who were lonely and 4.2 for substance users who were not lonely. Yet, relative risk for severe hopelessness in substance-using lonely adolescents was 25.2. Lonely, substance-using adolescents were 25 times more likely to be severely hopeless than the reference group composed of non-substance using, not-lonely adolescents. Lonely adolescents who get drunk also were 15.9 times more likely to be severely hopeless than the reference group. Because hopelessness often is an indicator of suicidal behavior, these results may have important implications for school health adolescent suicide prevention efforts.

Demoralization and living alone: outcome from an urban community study.

The purpose of the present study was to investigate differences in demoralization between those who live in single-person households and those who live in households with others in a random sample of 8,634 urban adults. Responses to the 26-item Psychiatric Epidemiologic Research Interview did not substantiate that adults who live alone are more likely to be demoralized than those who live with others, until age and gender are considered. Men who live alone scored higher on demoralization than men who live with others, yet women who live with others scored higher on demoralization than those who live alone. An interaction for living arrangement and age group on demoralization was also observed.

Demographic predictors of self-reported loneliness in adults.

The relative magnitude of individual demographic characteristics, compared with other demographic characteristics, in the prediction or explanation of frequency of loneliness has not been examined or reported in the literature. The relative strengths of a series of demographic variables (gender, age, marital status, household income, educational attainment, race or ethnicity, employment status, and occupation) in explaining frequency of loneliness in a random sample of 8,634 adults residing in a large metropolitan county were examined. Logistic regression analysis indicated several variables significantly affected group membership as lonely vs not lonely: marital status, household income, gender, and educational attainment. The strongest predictor of all was marital status. Age group as a predictor variable approached significance, but employment status, occupational, and race/ethnicity were not significant predictors of group membership as lonely vs not lonely in the logistic regression model.

Loneliness and alcoholism risk in late adolescence: a comparative study of adults and adolescents.

The Short Michigan Alcoholism Screening Test (SMAST) was administered via phone survey to a random sample of subjects 18 years of age and older in a large metropolitan county. Among late adolescents (aged 18 to 20), lonely females had the highest mean score on the SMAST, indicating a higher degree of alcoholism risk than lonely males and nonlonely males and females. Among lonely females, late adolescents scored higher on the SMAST than any other age group. For males, loneliness did not appear to increase alcoholism risk in the late adolescent age group, but did appear to do so during the early and middle adulthood years. The implications of these findings for mental health professionals and adolescent substance abuse treatment personnel are discussed.

Shyness and sociability: a dangerous combination for illicit substance use in adolescent males?

Researchers have hypothesized that behavioral problems are accentuated when a shy person wants to be with other people. This need to be with others--sociability--is a related but separate construct from shyness. The purpose of the present study was to examine the relationship of shyness and sociability to illicit substance use in a sample of 654 male high school students. It was found that, in general, shy male adolescents were significantly more likely to use illicit substances when compared to those who were not shy. Those who were shy and highly sociable were significantly more likely to use hallucinogenic substances than were those who were shy and low to moderate in sociability as well as those who were not shy. Although not significant, there was a trend toward more cocaine and marijuana use among those who were shy and highly sociable. The implications of these findings for those who work with adolescents are discussed.

Shyness as a risk factor for adolescent substance use.

The role of shyness in adolescent substance use was examined in a sample of about 1,300 high school students from 14 senior high schools. Sample members were classified as not-shy, shy, or super-shy based on scores from an established measure of shyness, the Cheek and Buss Shyness Scale. Significant shyness category by gender interaction analysis of variance effects and gender-specific chi-square analyses indicated shy males were more likely to use marijuana or hashish, cocaine, amphetamines, and hallucinogenic substances than not-shy males and females. Further, super-shy males were more likely to report use of most of the substances than shy males. Super-shy females were less likely to drink alcohol than females who were less shy or not-shy. Findings from this study, as well as studies investigating other behavioral problems, suggest shyness may be more a burden for males than for females. Use of certain substances may assist very shy males cope with shyness by reducing psychosocial discomfort and inhibition.