Early initiation of sex,drug-related risk behaviors,and sensation-seeking among urban,low-income African-American adolescents

The purpose of this study was to examine the relationship of early initiation of sex, drug-use, drug-trafficking, and sensation-seeking among urban, African-American adolescents. A longitudinal follow-up of 383 youth ages 9 to 15 years at baseline over four years with serial risk-assessments was used. Sexual experience and several drug-related risk behaviors increased significantly during the four-year study interval. Sensation-seeking scores were higher after the baseline assessment among youth reporting tobacco, alcohol, and marijuana use and were higher, both at baseline and through several follow-up assessments, among youth reporting drug-selling and sexual activity. At baseline, the correlations among drug-related risk behaviors were all strong, except those between initiation of sex and drug-related risk behaviors. However, over time, early initiators of sex were significantly more likely to report involvement in substance use and drug-delivery/sales than were late initiators. Youth reporting repeated involvement in drug-related activities were more likely to report intensive sexual involvement than they were to report experimental sex or no sex. Sensation-seeking scores were lower among youth reporting no involvement in risk behaviors. However, scores did not differ between youth exhibiting experimental behavior compared to youth demonstrating repeated risk involvement. These results support the need for alternative experiences for youth exhibiting high levels of sensation-seeking and the need for early drug/sexual risk prevention programs.     

Environmental conditions and variation in levels of sun exposure among children in child care

Sun exposure in childhood is 1 of the risk factors for developing skin cancer, yet little is known about levels of exposure at this age. This is particularly important in countries with high levels of ultraviolet radiation (UVR) such as Australia. Among 49 children 3 to 5 years of age attending child care centers, UVR exposure was studied under 4 conditions in a repeated measures design; sunny days, cloudy days, teacher’s instruction to stay in the shade, and a health professionals instruction to apply sunscreen. Three different data collection methods were employed: (a) completion of questionnaire or diary by parents and researcher, (b) polysulphone dosimeter readings, and (c) observational audits (video recording). Results of this study indicated that more than half the children had been sunburnt (pink or red) and more than a third had experienced painful sunburn (sore or tender) in the last summer. Most wore short sleeve shirts, short skirts or shorts and cap, that do not provide optimal levels of skin protection. However, sunscreen was applied to all exposed parts before the children went out to the playground. Over the period of 1 hr (9–10 a.m.) the average amount of time children spent in full sun was 22 min. On sunny days there was more variation across children in the amount of sun exposure received. While the potential amount of UVR exposure for young children during the hour they were outside on a sunny day was 1.45 MED (Minimum Erythemal Dose), they received on average 0.35 MED, which is an insufficient amount to result in an erythemal response on fair skin even without the use of sunscreen.     

BDNF increases release probability and the size of a rapidly recycling vesicle pool within rat hippocampal excitatory synapses

Exerting its actions pre-, post- and peri-synaptically, brain-derived neurotrophic factor (BDNF) is one of the most potent modulators of hippocampal synaptic function. Here, we examined the effects of BDNF on a rapidly recycling pool (RRP) of vesicles within excitatory synapses. First, we estimated vesicular release in hippocampal cultures by performing FM4-64 imaging in terminals impinging on enhanced green fluorescent protein (eGFP)-labelled dendritic spines – a hallmark of excitatory synapses. Consistent with a modulation of the RRP, BDNF increased the evoked destaining rate of FM4-64 only during the initial phase of field stimulation. Multiphoton microscopy in acute hippocampal slices confirmed these observations by selectively imaging the RRP, which was loaded with FM1-43 by hyperosmotic shock. Slices exposed to BDNF showed an increase in the evoked and spontaneous rates of FM1-43 destaining from terminals in CA1 stratum radiatum, mostly representing excitatory terminals of Schaffer collaterals. Variance-mean analysis of evoked EPSCs in CA1 pyramidal neurons further confirmed that release probability is increased in BDNF-treated slices, without changes in the number of independent release sites or average postsynaptic quantal amplitude. Because BDNF was absent during dye loading, imaging, destaining and whole-cell recordings, these results demonstrate that BDNF induces a long-lasting enhancement in the probability of transmitter release at hippocampal excitatory synapses by modulating the RRP. Since the endogenous BDNF scavenger TrkB-IgG prevented the enhancement of FM1-43 destaining rate caused by induction of long-term potentiation in acute hippocampal slices, the modulation of a rapidly recycling vesicle pool may underlie the role of BDNF in hippocampal long-term synaptic plasticity.     

Beyond your paycheck: an employee benefits primer

Most jobs are worth much more than their salaries. Paid vacations, sick leave, pensions, health insurance, and other benefits can add almost $3 to every $10 you earn in salary.     

Predictors of sun protective behaviors among school students

A random sample of students (N = 3,655) in Grades 7, 9, and 11 from 55 schools in Queensland (Australia) were surveyed about their sun protection knowledge, attitudes, and behaviors. An aggregate sun protection behavior index (SPBI) was developed from self-reported behaviors on a school day and a weekend day. Repeated measures regression analyses revealed that negative views of sun protection measures were associated with low scores on the SPBI, an association that was strongest among older students and in larger schools. Low perceived parental sun protective behaviors were associated with low SPBI ratings, and this association was greatest in small schools and on Saturdays. Older students had lower SPBI ratings, but their scores increased on Saturdays. Gender did not appear to be independently related to the SPBI after adjustment for the other variables. These findings reinforce the need for adolescent sun protection programs to address the complex interactions among psychological, social, and environmental factors that influence different subgroups of the student population.     

The influence of reported paternal attitudes on the decision to breast-feed

Objective: To identify factors that influence a woman's decision to breast-feed.
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions.     

Margin of safety for discharge after apnea in preterm infants

OBJECTIVE: Most neonatologists include an apnea-free period in the criteria for the discharge of preterm infants. However, the length of time one should wait after the cessation of apnea before sending an infant home without a monitor is debated. We undertook this study in an attempt to define a minimal and safe observation period between the time of the last apnea episode and discharge. METHODS: We reasoned that in infants with idiopathic apnea of prematurity, the intervals between days on which apnea occurs gradually increase until some point at which clinically significant apnea ceases. Therefore, knowledge about the intervals between days on which apnea occurred just before the last apnea would provide a reasonable estimate of the minimal safe observation interval between the last apnea and discharge. We reviewed the charts of 266 infants born in 1993 and 1994 at 相似文献   

Total versus subtotal hysterectomy: a survey of current views and practice among British gynaecologists.

This paper reports the results of a postal questionnaire, with a response rate of 61 per cent. It is clear from the results that subtotal hysterectomy is an unpopular operation in the United Kingdom. Although a majority of consultants felt that subtotal hysterectomy was less likely to affect urinary, bowel and sexual function, this did not seem to affect decision making. Seventy-eight per cent of female gynaecologists would prefer a total hysterectomy for themselves rather than a subtotal procedure.