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Cardiovascular intervention for high-risk families: the Heart Smart Program   总被引:2,自引:0,他引:2  
The Heart Smart Family Health Promotion Program is a multidisciplinary, school-based program for cardiovascular risk reduction among high-risk children and their families. As a program that includes young adults at high risk, it is adaptable to a clinical practice. Nineteen fourth and fifth graders were selected as probands for elevated risk factors after a general screening to identify families for an intervention program. Twenty-three parents participated in a 12-week program focused on eating, exercise, and smoking behavior changes enhanced by behavicral support strategies. Weekly sessions were held in the auditorium/cafeteria of the elementary school and consisted of orientation and presentations, cardiovascular (CV) screening with medical feedback, activities, self-monitoring, counseling, and contingency contracting. Information gathered before and after the program included medical history, CV health knowledge and relevant behavior, blood pressure, serum lipid and lipoprotein values, anthropometric measurements, and urine electrolyte excretion. Both children and parents showed positive changes in eating habits and physical activity and significant changes in knowledge and blood pressure levels, while the children halted their weight gain. We believe this multidisciplinary, behavior-oriented, school-based program can be an effective cardiovascular risk intervention adaptable for a clinical office practice.  相似文献   
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This report describes the first identification and characterization of three chromosome-21-specific DNA sequences (and reference sequences from other chromosomes) that are differentially methylated between peripheral blood and placental tissue, with the aim of providing epigenetic biomarkers for quantifying cell-free fetal DNA in maternal plasma. To select sequences to be screened for differential methylation, three strategies were adopted: (i) investigating promoters of highly differentially expressed genes; (ii) choosing 'random' promoter regions; and (iii) choosing 'random' non-promoter regions. Over 200 pre-selected DNA sequences were screened using a methylation-specific restriction enzyme assay. Differentially methylated sequences located at 21q22.3 (AIRE, SIM2 and ERG genes), 1q32.1 (CD48 gene and FAIM3 gene), 2p14 (ARHGAP25 gene) and 12q24 (SELPLG gene) were identified. Bisulphite conversion confirmed that CpG sites within the AIRE promoter region are highly differentially methylated, and optimized methylation-specific primers for this region that are highly specific for placental DNA were devised. Next, it was shown that the methylation status of chorionic villus sample DNA from first trimester pregnancies matched the hypermethylated state of term placenta. Thus there is no indication of a difference in methylation status between early and term pregnancy for the sequences tested. The identified sequences constitute candidate biomarkers for non-invasive prenatal diagnosis of Down syndrome.  相似文献   
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Cohesin component dynamics during meiotic prophase I in mammalian oocytes   总被引:7,自引:0,他引:7  
Cohesins are chromosomal proteins that form complexes involved in the maintenance of sister chromatid cohesion during division of somatic and germ cells. Three meiosis-specific cohesin subunits have been reported in mammals, REC8, STAG3 and SMC1 beta; their expression in mouse spermatocytes has also been described. Here we studied the localization of different meiotic and mitotic cohesin components during prophase I in human and murine female germ cells. In normal and atretic human fetal oocytes, from leptotene to diplotene stages, REC8 and STAG3 colocalize in fibers. In murine oocytes, SMC1beta, SMC3 and STAG3 are localized along fibers that correspond first to the chromosome axis and then to the synaptonemal complex in pachytene. Mitotic cohesin subunit RAD21 is also found in fibers that decorate the SC during prophase I in mouse oocytes, suggesting a role for this cohesin in mammalian sister chromatid cohesion in female meiosis. We observed that, unlike human oocytes, murine synaptonemal complex protein SYCP3 localizes to nucleoli throughout prophase I stages, and centromeres cluster in discrete locations from leptotene to dictyate. At difference from meiosis in male mice, the cohesin axis is progressively lost during the first week after birth in females with a parallel destruction of the axial elements at dictyate arrest, demonstrating sexual dimorphism in sister chromatid cohesion in meiosis.  相似文献   
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The distribution of the sympathetic innervation to the internal anal sphincter (IAS) and rectum and the occurrence of different types of adrenergic receptors in the two organs were investigated in anaesthetized cats. Anal pressure and rectal motility were recorded by a manometric and a volumetric method respectively. Division of both the hypogastric nerves (HGN) and the lumbar colonic nerves (LCN) reduced the anal pressure by 46 +/- 6% of the resting pressure (40.9 +/- 6.4 mmHg) and consistently increased rectal motility. Efferent electrical stimulation of the HGN as well as the LCN elicited a contraction in the anus and the rectum, which, at maximal stimulation, caused the anal pressure to reach a similar level to that recorded before division of these nerves. After injection of phentolamine the anal contraction was abolished, whereas the rectal contraction was either abolished or converted to a beta-adrenergic relaxation. Propranolol caused increased rectal contraction in response to stimulation of the HGN and the LCN, whereas the anal contraction was unaffected. The results imply that the sympathetic nerves exert a tonic excitatory effect on the IAS and a dual effect on the rectum in the cat. The results also indicate that sympathetic fibres to the IAS are conveyed in both the HGN and the LCN. Inhibitory beta-adrenergic receptors seem to be of minor importance in regulating anal pressure.  相似文献   
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The critical intravesical pressure range for extravascular absorption of irrigating fluid (EVA) during transurethral resection of the prostate (TURP) is determined by the pressure in the perivesical tissue. This means that the transmural bladder pressure (detrusor pressure), calculated by deducting perivesical pressure from intravesical pressure during cystometry, is the pressure gradient behind EVA. The transmural pressure in 6 patients undergoing TURP has been studied both before and during epidural anaesthesia, using both conventional medium-fast fill cystometry and "free-flow" cystometry through the resectoscope. Epidural block does not influence the transmural pressure response on filling the bladder and neither does the type of infusion. A positive transmural pressure, and thereby a pressure gradient for EVA, exists already during the very early phase of bladder filling. Incomplete perforation of the prostatic capsule and clotting, as well as the accumulation of irrigating fluid in the perivesical tissue, probably moderate the rate of absorption.  相似文献   
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PURPOSE: To describe a 4-year intervention targeting fruit/vegetable consumption by high school students. DESIGN: This is a cohort study involving six pairs of schools (n = 12) matched on gender, race, enrollment, and location with schools randomly assigned within pairs to intervention or control conditions. SETTING: Twelve Archdiocese of New Orleans high schools. SUBJECTS: Cohort was defined as students (n = 2339) who were ninth-graders in the 1993-94 school year who provided baseline data. INTERVENTION: Four components of the intervention are: (1) school-wide media-marketing campaign, (2) school-wide meal and snack modification, (3) classroom workshops and supplementary subject matter activities, and (4) parental involvement. MEASURES: Focus groups were conducted for target population input and program development. Process evaluation included student feedback on media-marketing intervention materials and activities reported here. Process measures also included school meal participation, student characteristics, and verification of intervention activities. RESULTS: Focus groups identified barriers to increased consumption of fruit and vegetables as lack of availability, variety, and inconsistency in taste. Student attitudes were favorable regarding a school program to improve diet and parental involvement. Low consumption of fruits/vegetables was reported. After a 2-month school-wide program introduction utilizing various media-marketing materials and activities, 93% of students were aware of the program and 96% could identify the healthy eating message. CONCLUSIONS: Program development can be guided and enriched by student input via focus groups. Media-marketing activities effectively delivered health messages and attracted students' attention. Materials and activities used were acceptable channels for increasing awareness, positive attitudes, and knowledge about fruits/vegetables.  相似文献   
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