Inhibition of the ERK pathway prevents HIVgp120-induced REM sleep increase.

Approximately 35% of HIV-infected subjects, both children and adults, exhibit alterations in the sleep-waking cycle. HIV surface glycoprotein gp120 has been postulated to contribute to this abnormality. For example, it has been reported that HIVgp120 modifies sleep in freely-moving rats and that it also activates the ERK pathway in brain slices. The goal of this work was to determine if sleep changes induced by HIVgp120 in normal rats are mediated by the MAPK pathway. Our results show that a single intraventricular administration of HIVgp120 selectively increases REMS and that such an increase can be prevented by U0126, an inhibitor of ERK activating enzyme, MEK. In contrast, SB202190, a MAPK-p38 inhibitor, had no effect on HIVgp120-induced increase in REMS. These results suggest that HIVgp120 increases REMS in the rat by specifically affecting the ERK signal transduction pathway.

Correlations among physical activity and eating behaviors in 4- to 7-year-old Anglo- and Mexican-American children.

Physical activity and dietary behaviors are often correlated in adults and adolescents. This association was examined in 351 Anglo- and Mexican-American children between the ages of 4 and 7 years. Behaviors were assessed by structured observations and interviews at home and school. Observed physical activity was significantly correlated with energy intake (r = .43), but was unrelated to the percentage of calories from total fat or saturated fat. Thus, interventions with young children to improve dietary behavior or physical activity should not be expected to automatically lead to changes in the other.

Determinants of dietary intake in a sample of white and Mexican-American children.

OBJECTIVE: To assess the influence of several potential psychosocial determinants on children's eating behavior. PARTICIPANTS: Three hundred fifty-one Mexican-American and non-Hispanic white children (mean age = 4.4 years old at baseline) participated in the San Diego Study of Children's Activity and Nutrition for up to 2.5 years. METHODS: Child's eating behavior was described by 3 dependent variables: total energy, percentage energy from fat, and sodium intake per 1,000 kcal. Dietary information was collected 4 days a year using a 24-hour food intake record, which was a combination of direct observation and interviews with food preparers. The 35 predictor variables from child, parental, demographic, and environmental domains were collected by behavioral observation, interviewer-administered questionnaires, and physical measurements. STATISTICAL ANALYSES: Bivariate and regression analyses via mixed linear models were performed. RESULTS: Variables from the children's domain (such as skinfold thickness and weight) had the strongest associations with energy intake; parental variables (such as fat avoidance behavior and prompts to increase children's food intake) were associated with child's percentage energy from fat and sodium intake. In regression analyses, parsimonious subsets of variables accounted for 46% of variance in energy intake (3 variables), 40% of the variance in percentage of energy from fat (4 variables), and 44% of variance in sodium intake per 1,000 kcal energy (1 variable) in between-subject variance components. CONCLUSIONS: Fat and sodium intake of children may be improved by improving parents' nutrition habits and by having parents encourage children to eat a healthful diet. Few modifiable correlates of children's energy intake were identified.

Direct home observations of the prompting of physical activity in sedentary and active Mexican- and Anglo-American children.

Social interactions are important correlates of physical activity in children. Previous studies used global measures; the present study examined the influence of specific social interactions on immediate physical activity in children with data obtained from the Behaviors of Eating and Activity for Child Health: Evaluation System (BEACHES). The study examined parental and peer prompting of physical activity at home among 178 Mexican-American and 113 Anglo-American children at age 4 years and again at age 6.5 years. Most activity prompts came from adults interacting with children when they were sedentary. A reduction in the frequency of prompts from baseline to follow-up occurred in the prompter group (adult or child peer), gender, ethnicity, and preprompted activity level categories. Children's responses to these prompts showed that as they aged, they seemed to rely less on the interpersonal (especially adult) aspects of their environment for cues to be more active.

Acute childhood diarrhoea and maternal time allocation in the northern central Sierra of Peru.

Interventions to improve child health depend, at least implicitly, on changing maternal knowledge and behaviour and a reallocation of maternal time. There have been few studies, however, of the time cost involved in the adoption of new health technologies and even fewer that examine changes in maternal activities in response to child illness. The present study examines maternal daytime activities and investigates changes that occur when children are ill. We examine the impact of acute childhood diarrhoea episodes on the activity patterns of the mother/caretaker in this setting. The results show that mothers alter their usual activity patterns only slightly in response to acute diarrhoea episodes in their children. They continue to perform the same variety of activities as when the children are healthy, although they are more likely to perform them with the child 'carried' on their back. There is some indication that diarrhoea perceived to be more severe did result in the mother acting as caretaker more frequently. These findings have important implications for health interventions that depend on changing the amount of maternal or caretaker time spent for child health technologies, but the implications may vary depending on the reasons for the observed lack of changes in caretaker activities.

PIP: During the daytime in the rural village of Macashca in the Callejon de Huaylas, Peru, data collecters conducted 30 minute interval spot check observations on the activities of 45 children aged 4-36 months and their mothers/caretakers to examine the effect of acute childhood diarrhea episodes on the activities of the mothers/caretakers. The mothers/caretakers took more than 2 hours/day to prepare meals and 0.13 hours/day to collect fuel and water. Mothers were the caretakers for about 70% of all observations. Overall, time spent on child care duties increased only slightly during acute diarrhea episodes. It increased markedly for children aged 12-18 months, however (230 vs. 415 minutes/day; p = 0.006). When mothers perceived diarrhea to be severe, the amount of time spent in caretaker activities increased (72% vs. 62% during health; p = 0.1). Time spent on productive activities (e.g., gardening, food preparation, and work for wages) did not change greatly during acute diarrhea episodes. Possible explanations why mothers did not change their activity patterns during acute diarrhea episodes include: lack of flexibility to change their activity patterns; diarrhea may not be perceived as a threat; and lack of knowledge of, or access to, diarrheal treatments other than herbal tea. These findings demonstrate the need for public health specialists to consider the amount of time spent on child health technologies when designing health interventions. Realistic assessments of the practice and efficacy of traditional caretaker patterns during diarrheal episodes should be conducted to design feasible, culturally appropriate, effective case management programs.

Parental prompting of smoking among adolescents in Tijuana, Mexico.

Latino adolescents in the United States and Mexico may have higher rates of tobacco experimentation than other ethnic groups, possibly due to cultural factors and parental influences. This study examined three parental behaviors that may prompt smoking in children in Grades 3, 5, 7, and 9 in Tijuana. Mexico. Surveys were administered to 758 students in randomly selected classes in randomly selected schools in Tijuana. The most frequent prompt was the smoking parent asking the child to buy cigarettes (about two thirds), whereas about 60% asked the child to light the parent's cigarette, and about 20% of smoking parents asked the child to place the cigarette in his or her mouth to light it. Rates of prompting were very low among third graders but increased by Grade 5. Mother's smoking was associated with higher rates of all three types of parental prompting.

Parental influences to smoke in Latino youth.

BACKGROUND: Latino youth have been found to have a higher prevalence of tobacco use than do other ethnic groups, possibly due to cultural factors and parental influences. METHODS: Seventh-grade students (N = 589) were surveyed in San Diego, California, and Tijuana, Mexico, to assess parental influences to smoke. These parental influence variables were studied with logistic regression, adjusting for age, sex, and number of parents who smoke. RESULTS: Among those whose parents smoke, Mexican students were asked to strike a match to light their parents' cigarettes significantly more often (57%) than Mexican-American students (37%) and U.S. Others (37%) (P < 0.05). Seventeen percent of the Mexican students reported having lit a cigarette in their own mouth for their parents, compared to 18% of Mexican-Americans and only 3% of U.S. Others (P < 0.01). Mexicans reported buying cigarettes for their parents more often (62%), compared with 36% for Mexican-Americans and 30% for U.S. Others (P < 0.01). Child smoking was only associated with friend offers of tobacco and parental prompts to light cigarettes in their mouths. CONCLUSION: Latino parents are inadvertently prompting their children to smoke. Smoking prevention programs targeting Latino youth may need to include a parental tobacco education component.

Sources and fates of mercury and methylmercury in Wisconsin lakes

The mercury cycle in seven northern Wisconsin seepage lakes was characterized by high atmospheric influx, removal by sedimentation and evasive efflux, and by in-lake transformation of Hg to biologically sequestered methyl Hg species. Direct depositional Hg loading from lhe atmosphere to lakes was roughly lO ug/m2/year, with rain and snow Lhe principal delivery vectors. Annual atmospheric Hg deposition exceeded estimated fish bioaccumulation by a factor of roughly 10. The atmospheric Hg inffux was roughly balanced by losses to sediments and the return of volatile Hg° to the atmosphere. The relative importance of sedimentation and gaseous evasion as Hg loss terms varied from lake to with sedimentationl/evasion ratios ranging from 9:1 to 1:1 in the seven lakes studied. Residence times for Hg varied from roughly 125 to 300 days in these lakes. Methyl-Hg in these lakes also had an atmospheric source, estimated to he roughly 1% of the total Hg inputs. Although the direct atmospheric deposition and sediment accumulation of methy-Hg was miuch lower than annual rates of methy-Hg bioaccumalation...

Correlates of physical activity at home in Mexican-American and Anglo-American preschool children.

Twenty-two potential correlates of children's physical activity were examined. Two hundred and one Mexican-American and 146 Anglo-American families with 4-year-old children were studied. Children's physical activity was directly observed in the evening at home on 4 visits for 1 hr each time. Anglo-American children and male children were found to be more active. Demographic variables explained 11% of the variance in children's physical activity. After adjusting for demographics, 3 children's variables and 6 social-family variables did not account for significantly more variance. Five environmental variables accounted for 11% additional variance. Variables observed concurrently with physical activity, such as time spent outdoors and prompts to be active, were highly associated with children's physical activity.

[The effectiveness of a program of smoking prevention among Mexican schoolchildren]. / Efectividad de un programa de prevención de tabaquismo en escolares mexicanos.

The main objective of this study was to determine if a program emphasizing training for coping with the social pressures to smoke cigarettes is effective in preventing initial experimentation in the same population. Six elementary schools in Tijuana, Mexico, were included in this prospective study with the participation of 168 sixth-graders. After a baseline survey students were randomly assigned to an intervention and a control group. A program that emphasizes peer-pressure resistance skills to avoid smoking was applied to the intervention group. The control group received no intervention. After 10 months a second survey was carried out in both groups. A significantly smaller proportion of subjects in the intervention group experimented with tobacco during the follow-up period when compared with controls (8.1% vs 20%; p < 0.05). Although designed as a prevention tool, the program also had a therapeutic effect. The proportion of subjects in the intervention group that quit smoking was significantly higher than that of the control group (72% vs 34.78%; p < 0.01). We conclude that this peer pressure resistance skill program was effective in preventing experimentation with tobacco among sixth graders in Tijuana, Mexico.

[Honduran experience with the control of acute infantile respiratory infections]. / Experiencia hondureña en el control de las infecciones respiratorias agudas infantiles.

The Honduran Ministry of Public Health and Social Welfare, in consultation with the HEALTHCOM Project of the Academy for Educational Development, conducted a national study that examined the characteristic patterns of acute respiratory infections (ARI) in children, as well as the measures being used to control them. Following an ethnographic analysis of the entire population, a pilot intervention program was developed to teach mothers how to recognize ARI symptoms and take appropriate measures in the case of mild, moderate, and severe episodes. The intervention consisted of teaching health workers (HW) in eight rural towns the most important aspects of ARI control and instructing them in a methodology for transmitting these concepts to the community through oral presentations in local health centers. The methodology included behavior modification techniques and incentives. Three observation instruments were used to compare the effectiveness of the health workers' presentations before and after their training, as well as the knowledge acquired by those who attended the presentations and the community at large. The results indicated that the techniques used both to train the HW and by them in their presentations helped the mothers and other members of the community to respond more effectively when children came down with acute respiratory infections of varying degrees of severity.

Identification of correlates of physical activity among Latino adults.

127 Latino adults responded to a survey concerning physical activity. Respondents over-represented well educated and middle class Latinos. Subjects reported a mean of 48 minutes/week of walking for exercise. This sample reported less than two episodes per week of vigorous physical activity, again below the recommended 3/wk needed to insure cardiovascular fitness. We expect more representative samples to engage in less physical activity. Stepwise multiple regression analyses were conducted using 24 variables based on Social Learning Theory. A multiple R of 0.66 accounted for over 27% of the variance in walking for exercise (p less than 0.001). Older adults, those with a history of childhood injury, and those who reported friend support were more likely to walk for exercise. Respondents who participated in physical activity during childhood and adolescence (including formal physical education in school) and, paradoxically, those who had models for exercise in childhood were less likely to walk for exercise. A multiple R of 0.75 accounted for 43% of the variance in vigorous physical activity and reached significance (p less than 0.001). Self-efficacy, friends' support, childhood physical activity, and eating a heart healthy diet were positively related to vigorous activity. These results suggest that different correlates influence walking versus vigorous activity, and that correlates of physical activity are different for Latinos compared to Anglos. The findings emphasize the need for larger scale investigations of the determinants of activity within the Latino population.

Maternal feeding behavior and child acceptance of food during diarrhea, convalescence, and health in the central Sierra of Peru.

Feeding patterns by mothers and child acceptance of food were measured in a Peruvian village to determine changes on days when children had diarrhea as compared to days of convalescence and health. Morbidity surveillance identified 40 children, aged 4-36 months, with diarrhea. Children were followed using twelve-hour in-home structured observations during two to four days each of diarrhea, convalescence, and health. Using scales of maternal encouragement to eat and child acceptance of food and cumulative logistic regression analyses, maternal encouragement to eat decreased significantly during convalescence compared to diarrheal days (OR: 0.54, 90% CI: 0.35, 0.82) and health compared to diarrhea (OR: 0.65, 90% CI: 0.46, 0.93). In contrast, child acceptance of food increased during health compared to diarrhea (OR: 1.55, 90% CI: 1.02, 2.35). Results illustrate the importance of carefully examining the behavioral aspects of nutritional intake. Decreases in intake during diarrhea are due to anorexia and not withdrawal of food by mothers. In response to reductions in child appetite during illness, mothers are more likely to encourage children to eat, while they tend to become more passive feeders after the diarrhea has stopped. Program efforts should focus on messages to feed children more actively especially after diarrhea episodes, when appetite levels increase.

The social epidemiology of smoking during pregnancy among Mexican women.

The association between maternal tobacco smoke exposure and hazards to reproduction has been investigated since the turn of the century. Numerous studies have demonstrated an increased risk to the developing fetus as a result of maternal smoking. This risk continues to manifest itself postnatally into childhood. The present study examined both risk factors for and consequences of smoking behavior among a sample of 50 pregnant women consecutively admitted to the obstetrics ward of the Tijuana General Hospital, Tijuana, Mexico. A questionnaire completed postpartum examined social, cultural, and economic variables for the mother, and physical variables of the newborn. Twenty-one subjects were smokers and 29 were nonsmokers. The number of previous pregnancies per subject was significantly higher in the group of smoking mothers. Overall, 86.2% of the nonsmoking mothers had three or fewer pregnancies versus 52.4% of the smoking mothers (p less than or equal to 0.005). It was also noted that the smoking subjects tended to be light smokers (90% reported smoking ten or fewer cigarettes a day, with an average of 4.27 years of smoking history). No difference in knowledge of the harmful effects of smoking during pregnancy was observed between the two groups; however, the proportion of subjects whose mothers and siblings also smoked was significantly higher (p less than or equal to 0.005 and p less than or equal to 0.01, respectively) in the smoking groups. The results are discussed in terms of antismoking prevention and health promotion programs for the developing world.

The well baby lottery: motivational procedures for increasing attendance at maternal and child health clinics.

A lottery system was used to improve attendance at four well baby clinics in four colonias in Tijuana, Mexico. Mothers earned one lottery ticket for each visit to each clinic during the intervention period. At the end of each month, ticket receipts were entered into drawings for one of three bags of groceries. The lottery system was evaluated within a "multiple baseline design" whereby the intervention was staggered across the four clinics on a month-by-month basis. Although attendance was not enhanced uniformly, an overall improvement of 25 percent was realized. The lottery system was at times hampered by administrative problems, such as the breakdown of a public address system used to announce the open hours of a clinic in one of the colonias.

PIP: A lottery system was used to improve attendance at 4 well baby clinics in 4 colonias in Tijuana, Mexico. Mothers earned 1 lottery ticket for each visit to each clinic during the intervention period. At the end of each month, ticket receipts were entered into drawings for 1 of 3 bags of groceries. The lottery system was evaluated within a multiple baseline design whereby the intervention was staggered across the 4 clinics on a month-by-month basis. Although attendance was not enhanced uniformly, an overall improvement of 25% was realized. The lottery system was hampered by administrative problems, such as the breakdown of a public address system used to announce the open hours of a clinic in 1 of the colonias. The present study shows that behavior modification can serve as an important constituent technique to an overall child survival strategy. However, behavior modification should never be considered in isolation but only with respect to other central requisite components of overall interventions that may be designed for enhancing the health, well-being, or at least survival of children under the age 5 in the world's developing countries.

Predictors of chewing tobacco and cigarette use in a multiethnic public school population.

Smoking and tobacco-chewing habits of sixth and seventh graders were investigated. Four hundred thirty-three white, black, Mexican-American, and Oriental students in San Diego public schools self-reported their tobacco use as well as perceptions of use among their peers and friends, parental socio-economic status, and other variables. One-third of the respondents had used some form of tobacco at least once, with cigarette smoking more common than chewing. Norm perceptions and best friend's habits predicted both smoking and chewing experimentation and prevalence. White males were more frequent "chewers," while blacks and Mexican-Americans were more frequent smokers. Significant associations between the two types of tobacco use were also found.

A Behavior Analysis of the Promotion of Oral Rehydration Therapy (ORT) in Guatemala.

The present report presents the results and preliminary recommendations of a behavior analysis study of an oral rehydration therapy (ORT) promotion in four localities in San Marcos, Guatemala. In this study, we used behavioral observation techniques to look at one-to-one communication and health education efforts in health clinics as well as to evaluate the effectiveness of these health education efforts by observing mothers' behavioral skills in their own homes. Subsequently, we also observed canalizatión (outreach) strategies to see whether we could learn more from these health workers' activities, and conducted "behavioral focus group" research with teams of health workers to determine how best to promote effective health education activities to other health workers. Results of our study indicate that health workers already spent a substantial amount of time doing health education and primary prevention, and were fairly effective at doing so. Their communication, however, tended to be relatively unilateral and failed to involve some of the more progressive aspects of behavioral skills training.

Patterns and Predictors of Cigarette use Among Public School Children in Tijuana, Mexico.

The use of cigarettes and other forms of tobacco poses a major and growing health threat to populations of developing countries. The present study examined the onset of cigarette use among public school students in Tijuana, Mexico. Fifty-four percent of the males and 34 percent of the females had experimented with smoking. Maternal smoking was more strongly associated with smoking among girls, while peer smoking had a relatively stronger association with future intentions to smoke among boys. Rates of smoking behavior among Mexican-American school children in nearby San Diego more closely resembled the higher rates of their Tijuana than those of their Anglo-American counterparts.

A review of the antituberculosis campaign in Mexico.

Tuberculosis, a major cause of death in the nineteenth century, has consistently and steadily declined in industrialized countries. Such decline antedates the introduction of specific treatment or immunization programs. In the United States of America, the tuberculosis problem is almost exclusively confined to ethnic minorities, socially marginal groups, and migratory workers. All the countries of Latin America have adopted the programs for tuberculosis control recommended by the World Health Organization and the Pan American Health Association. The degree to which these programs are followed in Mexico is critically discussed. A number of suggestions are offered to improve a program that appears to be insufficient in terms of controlling this disease.