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Journal of Behavioral Medicine - Understanding associations between mothers’ and children’s physical activity and sedentary behavior on more fine-grained timescales can provide insights...  相似文献   
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In order to prevent essential fatty acid (EFA) deficiency induced by fat-free total parenteral nutrition (TPN), 10 infants on TPN were rubbed three times daily for 20 days using oenethera oil (80% EFA). Total EFA amount provided cutaneously was 1900 mg/kg/d. Plasma and red blood cells phospholipids were determined on days 1 and 20 in these 10 treated and six untreated infants on TPN and compared with those of normal control infants. On day 1, plasma nonessential FA including 20:3 n-9(p less than 0.01) were increased in both TPN groups while 18:2 n-6 and 18:3 n-3 (p less than 0.001 and p less than 0.01) were decreased. On the 20th day, EFA deficiency had worsened with a decrease in plasma level of 20:4 n-6 (p less than 0.02) and a higher than normal triene/tetraene ratio : 3.4 +/- 1.1 and 2.3 +/- 0.6 vs 0.1 +/- 0.1 (p less than 0.02). As for red blood cells phospholipids, 16:0 was increased and 18:2 n-6 and 20:3 n-6 were decreased (p less than 0.05) on day 1. On day 20, these FA were more abnormal while 20:3 n-9 became significantly increased (p less than 0.05). No difference was observed between the TPN groups at any time. These results show that cutaneous application of large amounts of EFA-rich oil is unable to prevent or cure TPN induced EFA deficiency.  相似文献   
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S. T. Pendlebury  J. L. Pepin  D. Veale    P. Levy 《Thorax》1997,52(10):872-878
BACKGROUND: Obstructive sleep apnoea (OSA) is associated with increased morbidity and mortality. It has remained unclear whether or not it is progressive. The evolution of OSA was examined in a retrospective case note study of 55 unselected patients of mean (SD) age 55.8 (10) years with mild to moderate disease untreated by interventional methods such as continuous positive airway pressure (CPAP) or surgery. Correlations between clinical and functional variables, upper airway anatomy, and change in disease severity were also investigated. METHODS: Patients underwent full polysomnography on two occasions (T0 and Tx) at a mean interval of 77 (50) weeks (range 17-229). In addition, upper airway imaging with computed tomographic scanning or cephalometry had been performed in 43 patients at T0. Morbidity before, during, and after the study period was assessed by questionnaire, as was smoking history and alcohol and sedative intake. RESULTS: The apnoea hypopnoea index (AHI) for the group as a whole increased from 21.8 (11.5) to 33.4 (21.3) (p = 0.0001). Using a 25% change in AHI to divide patients into worsened, stable, and improved groups showed that, although most of the patients deteriorated, 25 patients improved or remained stable. The change in AHI was not correlated with body mass index which remained stable at 29.7 (5.4) kg/m2 versus 29.7 (5.6) kg/m2. There was a trend for apnoea duration to increase. No patient reported increased alcohol consumption and only one patient reported increased use of sedatives between T0 and Tx. No correlation was found between change in AHI and age, time between recordings, anatomical measurements of the upper airway, respiratory function, oximetry, or arterial blood gas tensions. Total cardiovascular and cerebrovascular morbidity was high: hypertension (26 patients, 46%), cardiac arrhythmia (17 patients, 33%), angina (12 patients, 23%), myocardial infarction (10 patients, 19%), and stroke (10 patients, 19%). Twenty nine patients (52%) were prescribed CPAP after Tx, two of whom went on to have maxillofacial surgery. These 29 treated patients had significantly higher values of AHI at T0 and Tx and greater change in AHI than the untreated patients. CONCLUSIONS: This study shows that mild to moderate OSA has a tendency to worsen in the absence of significant weight gain and that upper airway anatomy and clinical variables do not appear to be useful in predicting progression. It follows that mild to moderate OSA justifies systematic follow up. Deterioration in AHI over a mean of 17 months led to interventional treatment in over 50% of patients in the study.


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BACKGROUND: Research has sought to understand how environmental factors influence adolescent physical activity, yet little is known about where and with whom adolescents are physically active. PURPOSE: This study used electronic ecological momentary assessment (e.EMA) to map the social and physical contexts of exercise and walking across adolescence. Differences in physical activity contexts by gender, grade in school, day of the week, and season were examined. METHODS: Twice a year between 9th and 12th grade, 502 adolescents (51% female) of mixed ethnicity (55% White) participated in 4-day e.EMA intervals (Thursday-Sunday) where their primary activity (e.g., exercise, TV, homework), social company (e.g., friends, family, class), and physical location (e.g., home, school, outdoors) were assessed every 30 (+/-10) min during waking hours. RESULTS: Overall, greater proportions of exercise and walking were reported with friends, outdoors, and at school. However, boys were more likely to report exercising and walking in outdoor locations than girls. Exercising with classmates, family, and at school decreased across high school. Walking with family, friends, and outdoors also decreased. On weekdays compared to weekends, students reported a greater proportion of their exercise and walking at school. Students were more likely to report exercising and walking outdoors in the fall and the spring than in the winter. CONCLUSION: e.EMA showed that the social and physical contexts of adolescent exercise and walking vary as a function of gender, grade in school, day of the week, and season. Understanding the contexts of physical activity during the high school years can be helpful in designing interventions during adolescence.  相似文献   
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The renin-angiotensin system (RAS) is essential for blood pressure control and water-electrolyte balance. Until the discovery of the renin receptor, renin was believed to be mainly a circulating enzyme with a unique function, the cleavage of angiotensinogen. We report a unique mutation in the renin receptor gene (ATP6AP2) present in patients with X-linked mental retardation and epilepsy (OMIM no. 300423), but absent in 1200 control X-chromosomes. A silent mutation (c.321C>T, p.D107D) residing in a putative exonic splicing enhancer site resulted in inefficient inclusion of exon 4 in 50% of renin receptor mRNA, as demonstrated by quantitative RT-PCR. Analysis of membrane associated-receptor molecular forms showed the presence of full-length and truncated proteins in the patient. Functional analysis demonstrated that the mutated receptor could bind renin and increase renin catalytic activity, similar to the wild-type receptor, but resulted in a modest and reproducible impairment of ERK1/2 activation. Thus, our findings confirm the importance of the RAS in cognitive processes and indicate a novel specific role for the renin receptor in cognitive functions and brain development.  相似文献   
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A novel naturally occurring antiangiogenic agent isolated from cartilage, referred to as Neovastat (AE-941), was examined for its efficacy against tumor neovascularization and progression. Exposure to Neovastat results in ex ovo antiangiogenic properties in the chorioallantoid membrane of chicken embryo (71% decrease in the angiogenic index as compared to the basic fibroblast growth factor (bFGF) treated control embryos, P < 0.0001). Oral administration of Neovastat inhibits bFGF-induced angiogenesis in the Matrigel mouse model (87.5% decrease in hemoglobin as compared to the bFGF-treated control implants, P < 0.0001). Neovastat also induces a dose response decrease of lung metastases in the Lewis lung carcinoma model (oral administration; 69.1% of inhibition obtained at the maximal dose of 0.5 ml/day, P < 0.0001). Combined with a sub-optimal dose of cisplatinum (2 mg/kg, i.p.), Neovastat (0.5 ml/day) improved the therapeutic index by increasing the antimetastatic efficacy and by exerting a protective activity against cisplatinum-induced body weight loss and myelosuppression. In summary, our experimental data provide evidence of antiangiogenic and antimetastatic properties of Neovastat, following oral administration.  相似文献   
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Cytogenetic studies in lymphomas classically require fresh or frozen tissue, whereas in many instances only paraffin-embedded biopsies are available. We applied an interphase FISH assay on nuclei extracted from thick paraffin sections to determine accuracy of molecular cytogenetics in such samples. Twenty-three lymphoma samples and 4 reactive lymph nodes were tested with various commercially available DNA probes, and hybridization patterns were compared with those obtained on frozen nuclei counterparts. Successful hybridization with all probes tested was observed for 23/27 (85%) paraffin-embedded tissues and for all (100%) frozen samples, and cut-off levels defining positivity were superimposable for both situations. Chromosome changes were detected in the same way, without any false-positive or false-negative cases. Hybridization signals observed on dewaxed samples were either those classically expected to define the relevant chromosome change or were atypical: all atypical changes could be demonstrated also into nuclei from the frozen counterpart. Moreover, all typical and atypical chromosome changes observed on frozen nuclei were also detected in paraffin-embedded tissues. Our study shows that our interphase FISH assay performed on paraffin-embedded samples is a valuable alternate to conventional methods to ascertain diagnosis of lymphomas as to include patients into therapeutic trials.  相似文献   
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