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71.
Objective: Women 25 to 45 years old are at risk for weight gain and future obesity. This trial was designed to evaluate the efficacy of two interventions relative to a control group in preventing weight gain among normal or overweight women and to identify demographic, behavioral, and psychosocial factors related to weight gain prevention. Research Methods and Procedures: Healthy women (N = 284), ages 25 to 44, with BMI < 30 were randomized to one of three intervention conditions: a clinic‐based group, a correspondence course, or an information‐only control. Intervention was provided over 2 years, with a follow‐up at Year 3. BMI and factors related to eating and weight were assessed yearly. Results: Over the 3‐year study period, 40% (n = 114) of the women remained at or below baseline body weight (±2 lbs), and 60% gained weight (>2 lbs). Intervention had no effect on weight over time. Independently of intervention, women who were older, not actively dieting to lose weight, and who reported less perceived hunger at baseline were more likely to be successful at weight maintenance. Weight maintenance also was associated with increasing dietary restraint (conscious thoughts and purposeful behaviors to control calorie intake) and decreasing dietary disinhibition (the tendency to lose control over eating) over time. Discussion: This study raises concern about the feasibility and efficacy of weight gain prevention interventions because most women were interested in weight loss, rather than weight gain prevention, and the interventions had no effect on weight stability. Novel approaches to the prevention of weight gain are needed.  相似文献   
72.
Objective: To evaluate the effects of body adiposity on bone mineral density in the presence and absence of ovarian hormones in female mice and postmenopausal women. Research Methods and Procedures: We assessed percentage body fat, serum leptin levels, and bone mineral density in ovariectomized and non‐ovariectomized C57BL/6 female mice that had been fed various calorically dense diets to induce body weight profiles ranging from lean to very obese. Additionally, we assessed percentage body fat and whole body bone mineral density in 37 overweight and extremely obese postmenopausal women from the Women's Contraceptive and Reproductive Experiences study. Results: In mice, higher levels of body adiposity (>40% body fat) were associated with lower bone mineral density in ovariectomized C57BL/6 female mice. A similar trend was observed in a small sample of postmenopausal women. Discussion: The complementary studies in mice and women suggest that extreme obesity in postmenopausal women may be associated with reduced bone mineral density. Thus, extreme obesity (BMI > 40 kg/m2) may increase the risk for osteopenia and osteoporosis. Given the obesity epidemic in the U.S. and in many other countries, and, in particular, the rising number of extremely obese adult women, increased attention should be drawn to the significant and interrelated public health issues of obesity and osteoporosis.  相似文献   
73.
Peroxisome proliferator-activated receptor gamma (PPARgamma) and its response gene, Acyl CoA synthetase 5 (ACSL5), which has an important role in fatty acid metabolism, may affect weight loss in response to caloric restriction. Therefore, we aimed to determine whether these genes were involved in the interindividual response to dietary treatment. Genotypic/phenotypic comparisons were made between selected obese women from the quintiles losing the most (diet responsive, n = 74) and the quintiles losing the least (diet-resistant, n = 67) weight in the first 6 weeks of a 900-kcal formula diet. Two common PPARgamma single nucleotide polymorphisms, Pro(12)Ala and C1431T, and eight polymorphisms across the ACSL5 gene were selected for single locus and haplotypic association analyses. The PPARgamma Pro(12)Ala single nucleotide polymorphism was associated with diet resistance (odds ratio = 3.48, 95% confidence interval = 1.41 to 8.56, p = 0.03), and the rs2419621, located in the 5'untranslated region of the ACSL5 gene, displayed the strongest association with diet response (odds ratio = 3.45, 95% confidence interval = 1.61 to 7.69, p = 0.001). Skeletal muscle ACSL5 mRNA expression was significantly lower in carriers of the wildtype compared with the variant rs2419621 allele (p = 0.03). Our results suggest a link between PPARgamma2 and ACSL5 genotype and diet responsiveness.  相似文献   
74.
BackgroundInherited heart disease is becoming a substantial part of everyday cardiology practice while genetic counselling still only takes place at university hospitals. In this study we review our seven-year experience with cardiogenetic counselling in a non-university hospital. MethodsRetrospective analysis of patient records. ResultsA total number of 83 index patients were counselled. In 65 patients DNA tests were performed, resulting in 26 positive tests. In all patients with genotype confirmation of hereditary cardiovascular disease and in 32 families without a molecular diagnosis, family screening was advised. Out of 120 subsequently tested family members, 47 molecular genetic diagnoses were confirmed. ConclusionAlthough the number of patients reviewed was small, our data show that cardiogenetic diseases are part of daily cardiology practice. We believe counselling should be performed in more general hospitals. This is an excellent opportunity for collaboration between university and nonuniversity hospitals, with immediate benefit for patients and their relatives. (Neth Heart J 2007;15: 412-4.)  相似文献   
75.
巨细胞病毒(cytomegalovirus, CMV)在世界范围内均有较高的感染率,是最常见的先天性感染。先天性CMV感染可继发于母体原发性感染或非原发性感染。高达40%~50%的感染新生儿是在妊娠早期原发感染, 之后出现长期后遗症,主要包括先天性CMV感染相关听力损伤和神经后遗症。血清学检查对于确定原发性CMV感染至关重要。产前超声检查发现胎儿异常要警惕先天性CMV感染的可能性,磁共振成像有助于发现CMV相关脑异常。羊膜穿刺术是诊断胎儿CMV感染的金标准。加强育龄妇女及孕妇的卫生健康知识教育、减少CMV感染及抗病毒治疗是目前预防先天性CMV感染的主要措施。更昔洛韦及缬更昔洛韦是目前治疗CMV感染最有效的药物。高免疫球蛋白及CMV疫苗预防先天性 CMV 感染的作用尚无明确结论。  相似文献   
76.
Drapc1 expression during mouse embryonic development   总被引:2,自引:0,他引:2  
We identified the mouse homolog of human DRAPC1 (APCDD1) gene, shown to be a target of Wnt/beta-catenin signaling pathway in cancer cell lines. Analysis of its spatiotemporal expression in mouse embryos from E7.5 to E14 showed that Drapc1 is expressed during development of the extraembryonic structures, nervous system, vascular system and inner ear. In addition, Drapc1 is expressed in the mesenchyme of several developing organs at sites of epithelio-mesenchymal interactions. Drapc1 expression was also found in the hair follicles of the adult mouse skin. Similarity of Drapc1 expression pattern to location of active beta-catenin in developing mouse embryo further suggests that mouse Drapc1 is a novel in vivo target gene of Wnt/beta-catenin signaling pathway.  相似文献   
77.
The purpose of the study was to examine the validity of alpha1-microglobulin (alpha1-MG) in comparison with popularly used beta2-microglobulin (beta2-MG). A database was revisited to select ca. 7,500 spot urine samples (of adequate urine density) from non-pregnant, non-lactating and never-smoking adult women. The validity of the MGs was examined in terms of stability of the MG-uria prevalence in urine samples of various creatinine (CR or cr) concentration or specific gravity (SG or sg). Comparisons were made for MGs as observed (e.g., alpha1-MGob), as corrected for CR (e.g., alpha1-MGcr) and as corrected for SG of 1.016 (e.g., alpha1-MGsg). A cut-off value of 5.7 mg/g cr (or mg/l) for alpha1-MG was deduced from a cut-off value of 400 microg/g cr (or mcirog/l) for beta2-MG, because the correlation between alpha1-MGcr and beta2-MGcr was statistically significant. The prevalence of a 1-MGsg-uria was essentially unchanged (i.e., from a low of 13.6% to a high of 17.0%, or 1.2 times) except for in very dense or very thin urine samples, in contrast, beta2-MGcr-uria showed a substantial increase (from 0.0% to 2.8% with an infinite rate) as a reverse function of a decrease in CR in urine. The prevalence of uncorrected markers, i.e., alpha1-MGob-uria and beta2-MGob-uria, showed even greater CR- or SG-dependent changes. Thus, it appeared prudent to consider a alpha-MGsg rather than beta2-MGcr as a marker of tubular dysfunction among a general population with various urine density.  相似文献   
78.
It is well known that nitric oxide (NO), the most important vasodilator agent, plays an important role in lowering vascular resistance in the human umbilical-placental circulation and that its deficiency is related to the pathogenesis of pre-eclamptic disorder. Besides it has recently been demonstrated that human hemoglobin (HbA) is able to transport nitric oxide, as S-nitrosohemoglobin (SNO-Hb), from the arterial to the venous blood. In the present study we examine the functional properties of the adult and fetal nitrosated hemoglobins to see if the double transport of oxygen and NO may influence the fetal oxygenation and the relation between maternal and fetal blood. Our results show that S-nitrosation significantly increases the oxygen affinity of the adult Hb (HbA) with respect to native protein (no-nitrosated) while the functional properties of HbF are less influenced. The oxygen affinity modification, found for SNO-HbA, was ascribed to the nitrosation of cysteine beta 93: really, the same residue is also present in the gamma chains of fetal hemoglobin, while the increase of affinity is less evidenced; hence, it is probable that the 39 aminoacidic substitutions between beta and gamma chains allay the effects of S-nitrosation. As regards the physiological modulators (protons, chloride ions, 2,3-diphosphoglyceric acid, and temperature), they influence the oxygen affinity of the two hemoglobins S-nitrosated, in equal mode with respect to the native forms determining the same variation on the oxygen affinity. Hence, our results evidence the fact that the NO release by SNO-HbA "in vivo" would be limited to regions of extremely low oxygen tension (such as hypoxic regions), while in fetus, SNO-HbF would unload nitric oxide and oxygen at pressure values close to normal.  相似文献   
79.
Recent research communications indicate that the adult human brain contains undifferentiated, multipotent precursors or neural stem cells. It is not known, however, whether these cells can develop into fully functional neurons. We cultured cells from the adult human ventricular wall as neurospheres and passed them at the individual cell level to secondary neurospheres. Following dissociation and plating, the cells developed the antigen profile of the three main cell types in the brain (GFAP, astrocytes; O2, oligodendrocytes; and beta-III-tubulin/NeuN, neurons). More importantly, the cells developed the electrophysiological profiles of neurons and glia. Over a period of 3 weeks, neuron-like cells went through the same phases as neurons do during development in vivo, including up-regulation of inward Na+ -currents, drop in input resistance, shortening of the action potential, and hyperpolarization of the cell membrane. The cells developed overshooting action potentials with a mature configuration. Recordings in voltage-clamp mode displayed both the fast inactivating TTX-sensitive sodium current (INa) underlying the rising phase of the action potential and the two potassium currents terminating the action potential in mature neurons (IA and IK, sensitive to 4-AP and TEA, respectively). We have thus demonstrated that the human ventricular wall contains multipotent cells that can differentiate into functionally mature neurons.  相似文献   
80.
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