Scale development for perceived school climate for girls' physical activity

OBJECTIVES: To test an original scale assessing perceived school climate for girls' physical activity in middle school girls. METHODS: Confirmatory factor analysis (CFA) and structural equation modeling (SEM). RESULTS: CFA retained 5 of 14 original items. A model with 2 correlated factors, perceptions about teachers' and boys' behaviors, respectively, fit the data well in both sixth and eighth graders. SEM detected a positive, significant direct association of the teacher factor, but not the boy factor, with girls' self-reported physical activity. CONCLUSIONS: School climate for girls' physical activity is a measurable construct, and preliminary evidence suggests a relationship with physical activity.     

Thoracic wall involvement by Hodgkin disease and non-Hodgkin lymphoma: CT evaluation

Thoracic computed tomographic (CT) scans of 250 patients with newly diagnosed or recurrent lymphoma revealed thoracic wall involvement in 24 patients (11 with Hodgkin disease, 13 with non-Hodgkin lymphoma). Thoracic wall involvement occurred without contiguous mediastinal or parenchymal involvement in 17 patients. Of these, 13 patients had masses beneath the pectoralis muscles or within the breast, and four had masses arising from the ribs. Five additional patients had mediastinal masses with thymic involvement and parasternal extension through the thoracic wall. Pulmonary parenchymal lymphoma with thoracic wall invasion was noted in the remaining two patients. In five of nine patients receiving radiation therapy, treatment plans were modified by CT demonstration of thoracic wall lymphoma.     

Effect of cardiorespiratory fitness on mortality among hypertensive and normotensive women and men

BACKGROUND: The effects of fitness on mortality either from cardiovascular disease (CVD) or from all causes, among hypertensive adults, are not fully understood, especially among women. The objective of this study was to examine the effect of fitness on all-cause and CVD mortality among hypertensive and normotensive women and men. METHODS: Using the Lipids Research Clinics Prevalence Study, we examined the relationship of fitness with mortality among 2712 women and 3000 men followed from 1972-1976 to 1998. Cardiorespiratory fitness was measured using a treadmill test. Sex-specific hazard ratios (HRs) were calculated from proportional hazard models of fitness predicting all-cause or CVD mortality, adjusted for age, education, race, smoking, alcohol, body mass index, and hyperlipidemic sampling strata. RESULTS: Comparing the lowest with the highest quintile of fitness, the adjusted all-cause mortality among hypertensive women was 1.7 (95% confidence interval = 0.9-3.2) and among normotensive women was 2.3 (1.5-3.7). Comparing the same quintiles of fitness, the adjusted all-cause mortality among hypertensive men was 2.0 (1.2-3.4), and among normotensive men it was 1.9 (1.3-2.7). Elevated risks were also observed for CVD mortality. CONCLUSION: Higher levels of fitness were associated with a lower risk of all-cause and CVD mortality among both hypertensive and normotensive women and men.     

Self-reported overweight and obesity are not associated with concern about enough food among adults in New York and Louisiana

BACKGROUND: A causal relationship between hunger and obesity has been postulated. Two cross-sectional studies have found evidence to suggest an association between obesity and food insecurity among adult women, and a third study suggests an association between underweight and food insecurity among men. The purpose of this study was to investigate the association between concern about enough food and obesity in an adult population at the state level. METHODS: A cross-sectional analysis was conducted using 1999 data from the Behavioral Risk Factor Surveillance System (BRFSS), Social Context Module (n = 3,945). RESULTS: An 8.0% prevalence of concern about enough food was found in Louisiana, and an 11.8% prevalence was found in New York, and was positively associated with morbid obesity, RR = 2.20 (95% CI = 1.24, 3.90) and RR = 2.23 (95% CI = 1.30, 3.84), respectively. However, this association became nonsignificant after controlling for education, income, race/ethnicity, marital status, and general health. CONCLUSION: A very strong apparent relationship between concern about enough food and obesity could be entirely accounted for by the influences of socioeconomic variables. This emphasizes the need for longitudinal research studies using precise measures of weight, height, and food security.     

Overexpression of glial cell line-derived neurotrophic factor in the CNS rescues motoneurons from programmed cell death and promotes their long-term survival following axotomy

To study the role of one of the most potent motoneuron (MN) survival factors, glial cell line-derived neurotrophic factor (GDNF) derived from the CNS, we generated transgenic animals overexpressing GDNF under the control of an astrocyte-specific GFAP promoter. In situ hybridization revealed that GDNF was expressed at high levels in astrocytes throughout the brain and spinal cord. We analyzed the effects of CNS-derived GDNF on MN survival during the period of programmed cell death (PCD) and after nerve axotomy. In GFAP-GDNF mice at E15, E18, and P1, the survival of brachial MNs was increased on average by 30%, lumbar MNs by 20%, and thoracic MNs at P1 by 33%. GDNF also prevented MN PCD in several cranial motor nuclei. We demonstrated for the first time that the number of MNs in the mouse abducens nucleus was also increased by 40%, thus extending known MN populations that are responsive to GDNF. Next, we tested if GDNF could support complete and relatively long-term survival of MNs following neonatal facial nerve axotomy. We found that virtually all MNs (91%) in GFAP-GDNF mice survived for up to 18 weeks post-axotomy. This is the longest GDNF-mediated survival of neonatal MNs reported following axotomy. Most of surviving MNs were not atrophic, and MN-specific ChAT and neurofilament immunoreactivity (IR) were preserved. Furthermore, GDNF attenuated axotomy-induced astroglial activation. These data demonstrate that overexpression of GDNF in the CNS has very profound effects on MN survival both during the PCD period and after neuronal injury. GFAP-GDNF mice will be valuable to study the effects of CNS-derived GDNF in mouse models of MN degenerative diseases and axonal regeneration in vivo.     

Leukocytospermia is associated with increased reactive oxygen species production by human spermatozoa

To investigate the role of increased seminal leukocytes in enhancing reactive oxygen species (ROS) production by human spermatozoa.A prospective study.Male infertility clinic.Forty-eight infertile men.Standard semen analysis. Assessment of sperm nuclear DNA damage by sperm chromatin structure assay. Incubation of spermatozoa from nonleukocytospermic samples with blood neutrophils.Spontaneous and phorbol 12-myristate 13-acetate (PMA)-induced ROS production in pure-sperm suspensions (after removal of leukocytes) as measured by a chemiluminescence assay.Levels of spontaneous and PMA-induced ROS production in pure-sperm suspensions from the infertile men with a diagnosis of leukocytospermia (n = 16) were significantly higher compared with the case of infertile men without leukocytospermia (n = 32) and with the case of a control group of healthy volunteers (n = 13). A similar pattern of increased ROS was observed when spermatozoa were incubated with blood neutrophils. Leukocytospermia was associated with a significant decrease in sperm motility and increase in DNA damage.Increased seminal leukocytes may play a role in stimulating ROS production by human spermatozoa. Such stimulation may be mediated via direct cell-cell contact or by soluble products released by leukocytes. Poor sperm quality in leukocytospermic samples may be due to leukocyte-mediated oxidative stress.     

Occupational physical activity in the atherosclerosis risk in communities study

PURPOSE: Accumulation of physical activity throughout the day is recommended to reduce health risks and enhance quality of life. Yet, many epidemiologic studies measure leisure activity only, without assessment of occupational activity. The purposes of this study were to describe occupational activity and to quantify the association between occupational and leisure activity in 2991 African American and 8566 White middle-aged adults. METHODS: Physical activity was measured by the Baecke questionnaire in 1987-89 for participants 45 to 64 years of age in the Atherosclerosis Risk in Communities Study. RESULTS: Reported occupational activity was greater among African American men and women compared to White men and women. Leisure activity was greater among White men and women compared to African American men and women. Work indices (range-1 (low) to 5 (high)) were highest among African American women (2.78) and men (2.72), followed by White men (2.55) and women (2.45), adjusted for age, study center, body mass index, and perceived health status. Those with the highest occupational activity had lower participation in any sport or exercise than those with lower occupational activity across race-gender groups. CONCLUSIONS: This data suggests that studies relying solely on leisure activity may miss important information provided by occupational physical activity.     

Chromatin structure in globozoospermia: a case report

Sperm nuclear abnormalities in patients with globozoospermia have not been well characterized and may lead to the high rates of fertilization failure and embryo loss reported in patients with this form of teratozoospermia. This study used transmission electron microscopy (TEM), the sperm chromatin structure assay (SCSA), and single cell gel eletrophoresis assay (COMET) to assess if globozoospermia is associated with sperm chromatin structure abnormalities, DNA fragmentation, or both. The flow cytometric SCSA measures abnormal chromatin structure based on the susceptibility of sperm nuclear DNA to acid-induced denaturation in situ. COMET measures DNA fragmentation in individual sperm nuclei based upon gel electrophoretic patterns. Although sperm concentration (113 million/mL) and motility (66%) were normal in the patient, there was complete acrosome deficiency. TEM and SCSA data confirmed light microscopic examination that showed that sperm populations included a mixture of round and elongated sperm heads. Even though 100% of sperm had abnormal head morphology, only 13% demonstrated DNA denaturation (COMPalpha(t)), which is below our threshold of 15% COMPalpha(t), and consistent with high-fertility patients. Of interest, 13% of the sperm were also positive in the COMET assay, supporting our previous observations that SCSA-positive cells are also positive for DNA fragmentation. It was unexpected but of great interest that a human sperm population with 100% sperm morphology abnormalities had a chromatin integrity at the molecular level that is equivalent to sperm populations shown in previous studies to be highly fertile. These data are the first reported using SCSA and COMET assays to evaluate a patient with globozoospermia and support previous reports that intracytoplasmic sperm injection of globozoospermia may result in fertility/pregnancy. Lower success rates seen in some patients may be due to unrelated factors.     

Breastfeeding and childhood asthma: a six-year population-based cohort study

Background  

The question of the protective effect of breastfeeding on development of asthma has raised substantial interest, but the scientific evidence of the optimal duration of breastfeeding is controversial.