Children's eating behavior: the importance of nutrition standards for foods in schools.

BACKGROUND: To enhance the impact of school nutrition programs on children's health, more information is needed on the associations between healthy and unhealthy food offerings during school lunch periods and children's eating behavior. The purpose of this study is to evaluate the contributions of food offerings and participation in school lunch programs on children's overall (both in- and out-of-school) eating behavior. METHODS: A cross-sectional observational study was conducted in which 2039 students in 12 elementary and 10 middle schools reported their eating behavior and the frequencies with which they purchased meals and à la carte items in the school cafeteria. Food service managers from each school provided information on the availability of foods and beverages during school lunch periods. Multilevel regression analyses were conducted to identify school- and student-level predictors of children's eating behavior. RESULTS: The availability of nutritious foods during school lunch periods was associated with healthier eating behavior among students. However, this effect was observed only among children who infrequently purchased à la carte food items, and not among those who were frequent purchasers. CONCLUSION: Increased availability of fruits, vegetables, whole grains, and low-fat dairy products as components of school meals may be an effective strategy to promote healthy eating behaviors among children. Improving the nutrition standards for foods offered in competition with federally reimbursable school meals may enhance the positive effects of school meal programs on student eating behavior.

Physical education resources, class management, and student physical activity levels: a structure-process-outcome approach to evaluating physical education effectiveness.

BACKGROUND: This study was conducted to empirically evaluate specific human, curricular, and material resources that maximize student opportunities for physical activity during physical education (PE) class time. A structure-process-outcome model was proposed to identify the resources that influence the frequency of PE and intensity of physical activity during PE. The proportion of class time devoted to management was evaluated as a potential mediator of the relations between resource availability and student activity levels. METHODS: Data for this cross-sectional study were collected from interviews conducted with 46 physical educators and the systematic observation of 184 PE sessions in 34 schools. Regression analyses were conducted to test for the main effects of resource availability and the mediating role of class management. RESULTS: Students who attended schools with a low student-to-physical educator ratio had more PE time and engaged in higher levels of physical activity during class time. Access to adequate PE equipment and facilities was positively associated with student activity levels. The availability of a greater number of physical educators per student was found to impact student activity levels by reducing the amount of session time devoted to class management. CONCLUSION: The identification of structure and process predictors of student activity levels in PE will support the allocation of resources and encourage instructional practices that best support increased student activity levels in the most cost-effective way possible. Implications for PE policies and programs are discussed.

Individual and Instructional Determinants of Student Engagement in Physical Education.

This study was conducted to identify student characteristics and instructional factors that impact student engagement in physical education (PE). Data were derived from the systematic observation of 124 sessions taught by 31 physical educators and the administration of health and PE engagement questionnaires to 2,018 students in grades 5-8. Physical activity was directly affected by student engagement and perceived competence in PE and indirectly affected by students' body image through its association with PE engagement. Multilevel analyses revealed that the proportion of class time devoted to game play was negatively associated with student engagement in PE. Although less frequently used during PE sessions, skill practice was positively associated with student engagement and inactive instruction was negatively associated with student engagement. These effects were particularly pronounced among students with poor competence beliefs. Implications for PE instructional practice and future research are presented.

[Seminal profile in workers exposed to cholinesterase inhibitor insecticides]. / Perfil seminal en trabajadores expuestos a plaguicidas inhibidores de la colinesterasa.

The objective of this study was to determine the physical, chemical and cytomorphologic characteristics of semen obtained from workers exposed to cholinesterase inhibitor insecticides and compare them with samples of the same nature obtained from unexposed subjects, and in addition, to correlate those findings with blood levels of cholinesterase. The study group consisted of 29 adult males, age range 20-54, that were exposed to cholinesterase inhibitor insecticides during 4 hours per day for a variable lapse (one year minimum), whereas the control group consisted of 30 unexposed individuals of the same gender, and similar age range. A thorough medical examination was performed in every individual. It consisted of an occupational medical history and complete physical exam. A blood sample was obtained in all the subjects in order to determine total cholinesterase levels by the modified S. Hestrin Hydroxamate method. Semen analysis was done in specimens collected after recent masturbation following a 3-day abstinence period. The data was processed and analyzed by the SAS computerized statistics program. The results revealed significant differences between both groups (p < 0.05) for the following variables: sperm count per mL., percentage of fast, mobile and immobile, live and dead spermatozoids. Spermatozoa morphology was found to be within normal limits as established by the WHO. Nevertheless, the differences related to the percentage of big head and amorphous spermatozoids was significant (p < 0.05). The results indicate that cholinesterase inhibitor insecticides affect certain variables of the semen analysis and hence the quality of the semen.

Perfil seminal en trabajadores expuestos a plaguicidas inhibidores de la colinesterasa / Seminal profile in workers exposed to cholinesterase inhibitor insecticides

El objetivo del presente estudio fue determinar y comparar las características físico-químicas y citomorfológicas del semen, en trabajadores expuestos a plaguicidas inhibidores de la colinesterasa, y relacionar estos hallazgos con los niveles de colinesterasa total de sangre. Se estudiaron 30 individuos no expuestos y 29 expuestos, del sexo masculino, entre 20 y 54 años de edad, con una exposición promedio de 4 horas diarias a plaguicidas inhibidores de la colinesterasa, durante un período variable de tiempo (con un año mínimo de exposición). A todos los sujetos estudiados se les realizó una evaluación médica, mediante historia médico ocupacional y examen físico completo. De cada uno de ellos se obtuvo muestra sanguínea para determinar niveles de colinesterasa total, mediante el método del hidroxamato de Hestrin modificado. Se practicaron espermatogramas en muestras de semen obtenidas por masturbación reciente, luego de un período de abstinencia sexual de 3 días. Los datos obtenidos se procesaron y analizaron con el programa estadístico computarizado SAS. Los resultados mostraron diferencias significativas (p< 0,05) entre el grupo control y el grupo expuesto para las variables: concentración espermática por mL y total, porcentaje de espermatozoides rápidos, móviles e inmóviles, vivos y muertos. La morfología espermática se encontró dentro lo establecido como normal por la O.M.S; sin embargo, hubo diferencias significativas entre el porcentaje de mégalos y amorfos (p< 0,05). Los resultados indican que los plaguicidas inhibidores de la colinesterasa afectan algunas variables del espermatograma y por lo tanto la calidad del semen

Health service utilization by Alzheimer's disease patients: a 2-year follow-up of primary versus subspecialty care.

All dementia patients and their caregivers who had received a university-based comprehensive evaluation and a diagnosis of Alzheimer's disease during 1997 (N = 80) were identified. Of the original cohort, 48.8% (n = 39) were able to be contacted approximately 2 years after their initial assessment, and the caregivers were the informants for this follow-up. Two subgroups were defined: 22 patients were being seen only by their primary care physicians (MED), while 17 patients were also being treated by a geriatric psychiatry faculty member (GERO). There were statistically significant differences between the 2 groups (MED versus GERO, respectively) at follow-up in terms of (1) institutionalization (30.0% versus 4.6%, P < .05), (2) CDR (2.3 versus 1.5, P < .005), and (3) prescription of donepezil at follow-up (45.5% versus 76.5%, P = .05). These differences are being assessed in a larger scale prospective study.

El control de los desencadenantes inhalables disminuye el requerimiento prolongado de farmacoterapia en pacientes asmáticos / Control of inhalable triggering factors decrease pharmacotherapy requirement in patients with asthma

Los conocimientos adquiridos durante la última década de investigación sobre la inmunopatología del asma han demostrado que el proceso inflamatorio es un factor preponderante de la enfermedad. Además de la herencia, la presencia de desencadenantes inhalables son los elementos predisponibles más importantes. El presente trabajo constituye un estudio clínico terapéutico longitudinal, diseñado para valorar el efecto de la combinación del uso de farmacoterapia y control medio-ambiental, en 45 pacientes asmáticos pediátricos procedentes de la consulta de Inmunología Clínica. Los pacientes admitidos en el estudio, presentaron por lo menos dos crisis asmáticas mensuales durante los últimos cuatro meses. Al ingresar en nuestra consulta, los pacientes recibieron tratamiento farmacológico único con teofilina (grupo A), beclometasona (grupo B) o salbutamol (grupo C), durante las dos primeras semanas, combinado con medidas específicas de control de desencadenantes inhalables. Después de un período de observación de 6 meses, se evidenció mejoría clínica estable, asociado a una modificación favorable del FEVI, CVF y PEF, disminución significativa de los niveles séricos de IgE en los tres grupos (p<0,02; 0,005 y 0,02 respectivamente) independientemente del fármaco utilizado. Durante el estudio se monitoreo la cantidad de ácaros, presentes en muestras tomadas de las viviendas, observándose una disminución de los mismos, asociado con la mejoría clínica de los pacientes. Sólo en aquellos pacientes en quienes persistieron los síntomas (grupo A 31 por ciento, grupo B 29 por ciento y grupo C 9 por ciento) se comprobó que las medidas de control de desencadenantes ambientales no se cumplieron cabalmente. Esos pacientes mejoraron notoriamente al sistematizar la aplicación de las medidas higiénicas sin requerir nuevamente de farmacoterapia. estos resultados nos permiten sugerir que la disminución de los desencadenantes inhalables es fundamental para el control de los pacientes asmáticos, en combinación con una farmacoterapia