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51.
The aim of this study was to monitor serum leptin concentrations after altering the levels of testosterone, by intramuscular administration of human chorionic gonadotropin (hCG), in eugonadal men. A 7-day monitoring of hCG, testosterone and leptin levels was performed after intramuscular administration of a dose of 5000 IU hCG in these men. Thirty fertile men aged 23-38 years were studied. In addition, 30 women aged 18-34 years with normal ovulatory cycles were studied, to verify reports of sexual dimorphism in serum leptin levels. These 60 individuals were divided into four groups, according to their sex and body mass index (BMI) values. In men, blood samples were collected at 09.00, after an overnight fast, for the determination of hCG, testosterone and leptin levels, and, immediately thereafter, a dose of 5000 IU hCG was administered intramuscularly. Further blood samples were collected at 24-h intervals for a period of 7 days for determination of the same hormones. In women, blood samples were collected only once, at 09.00, after an overnight fast between the 3rd and the 6th day of the menstrual cycle, for determination of serum estradiol and leptin levels. Our results showed that the mean value of leptin in thin men and women was significantly lower than that in obese men and women, respectively. The mean value of leptin in thin women was significantly higher than that in obese men. Serum leptin concentrations decreased significantly, 168 h after short-term hCG administration. There was a significant positive correlation between BMI values and serum leptin concentrations, in both men and women. Our results support the view that hCG administration in eugonadal men does not influence serum leptin levels. Moreover, a short-term increase of serum testosterone levels, after one dose of hCG, is not sufficient to affect and modify leptin secretion mechanisms in vivo.  相似文献   
52.
Objective:?To study the changes in the lecithin/sphingomyelin (L/S) ratio and lamellar body count (LBC) during pregnancy and to study the effect of clinical characteristics on these measurements. Methods:?We reviewed in retrospect the amniotic fluid samples for the assessment of fetal lung maturity of consecutive women between January 1996 and December 2000. We evaluated the effect of antenatal administration of glucocorticoids, the presence of diabetes, fetal growth restriction and the amount of amniotic fluid on the L/S ratio and LBC. We then constructed normal curves, by relating the L/S ratio and LBC to gestational age in the cases without respiratory distress syndrome (RDS). Data from the literature were added to these curves. Results:?From the 334 included women, 64 infants (19%) developed RDS. The LBC was lower in women withpolyh ydramnios (p?=?0.04), and similar in women witholigoh ydramnios. Administration of glucocorticoids, the presence of maternal diabetes or fetal growth restriction did not affect the L/S ratio or the LBC. The median L/S ratio in cases without RDS showed a constant increase from a gestational age of 28 weeks onwards. The median LBC increased slowly between a gestational age of 28 weeks and 34 weeks, to increase more steeply thereafter. Conclusion:?The amount of amniotic fluid affects the LBC, but not the L/S ratio. Since the L/S ratio and the LBC increase with gestation, differences in gestational age should be taken into account in the interpretation of these fetal lung maturity tests.  相似文献   
53.
Recent studies suggest that patients with type 2 diabetes mellitus are at increased risk of fracture, possibly because hyperinsulinemia is a risk factor for low bone mineral density, which may in turn be a consequence of a lipotoxic effect of visceral and/or intramuscular fat on bone. In the current study, we investigated whether insulin plays a role in cortical bone development by performing a cross-sectional study based on the Avon Longitudinal Study of Parents and Children (ALSPAC), where we examined associations between fasting insulin levels and peripheral quantitative computed tomography (pQCT) parameters as assessed at the mid-tibia in 2784 boys and girls with a mean age 15.5 years. In particular, we wished to examine whether associations that we observed were independent of body composition, including intramuscular fat. We found that insulin was inversely related to cortical bone mineral density (BMD(C)) after adjustment for age and after further adjustment for height, muscle cross-sectional area (MCSA), subcutaneous fat (SAT), and muscle density (MD), which is inversely related to intramuscular fat (-0.018, 95% confidence interval [CI] -0.030, -0.006, p < 0.0001). Insulin was positively related to periosteal circumference (PC) after adjusting for age (0.015, 95% CI 0.003, 0.027, p = 0.015; beta = change per 50% increase in insulin), but this changed to an inverse association after additional adjustment for height and body composition (-0.013, 95% CI -0.022, -0.003, p = 0.008). Path analyses revealed inverse associations between insulin and PC via a direct pathway (-0.012, 95% CI -0.022, -0.003, p = 0.01) and via MD (-0.002, 95% CI -0.004, -0.001, p = 0.0004), and positive associations between insulin and PC via SAT (0.013, 95% CI 0.009, 0.016, p < 0.0001) and MCSA (0.015, 95% CI 0.010, 0.020, p < 0.0001). In conclusion, we found an inverse relationship between insulin and PC via intramuscular fat, suggesting a lipotoxic effect on bone. However, an inverse association between insulin and both PC and BMD(C) persisted after adjusting for all body composition variables, suggesting insulin also acts to inhibit bone development via additional pathways yet to be elucidated.  相似文献   
54.
Mid‐thigh cross‐sectional muscle area (CSA), muscle attenuation, and greater trochanter soft tissue thickness have been shown to be independent risk factors of hip fracture. Our aim was to determine whether muscle and adipose tissue measures derived from dual‐energy X‐ray absorptiometry (DXA) scans would have a similar risk association as those measured using other imaging methods. Using a case‐cohort study design, we identified 169 incident hip fracture cases over an average of 13.5 years among participants from the Health ABC Study, a prospective study of 3075 individuals initially aged 70 to 79 years. We modeled the thigh 3D geometry and compared DXA and computed tomography (CT) measures. DXA‐derived thigh CSA, muscle attenuation, and subcutaneous fat thickness were found to be highly correlated to their CT counterparts (Pearson's r = 0.82, 0.45, and 0.91, respectively; p < 0.05). The fracture risk of men and women were calculated separately. We found that decreased subcutaneous fat, CT thigh muscle attenuation, and appendicular lean mass by height squared (ALM/Ht2) were associated with fracture risk in men; hazard ratios (HR) = 1.44 (1.02, 2.02), 1.40 (1.05, 1.85), and 0.58 (0.36, 0.91), respectively, after adjusting for age, race, clinical site, body mass index (BMI), chronic disease, hip bone mineral density (BMD), self‐reported health, alcohol use, smoking status, education, physical activity, and cognitive function. In a similar model for women, only decreases in subcutaneous fat and DXA CSA were associated with hip fracture risk; HR = 1.39 (1.07, 1.82) and 0.78 (0.62, 0.97), respectively. Men with a high ALM/Ht2 and low subcutaneous fat thickness had greater than 8 times higher risk for hip fracture compared with those with low ALM/Ht2 and high subcutaneous fat. In women, ALM/Ht2 did not improve the model when subcutaneous fat was included. We conclude that the DXA‐derived subcutaneous fat thickness is a strong marker for hip fracture risk in both men and women, especially in men with high ALM/Ht2. © 2015 American Society for Bone and Mineral Research. © 2015 American Society for Bone and Mineral Research  相似文献   
55.
Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide. Obesity is a major risk factor for NAFLD and recently, low skeletal muscle mass emerged as additional risk factor for NAFLD. However, the different contributions of body mass index (BMI) to the risk of NAFLD are not yet well-known. We therefore studied body composition and muscle function with NAFLD in an elderly population-based study. Participants of European descent underwent dual-energy X-ray absorptiometry (DXA) and hepatic ultrasonography. NAFLD was defined as liver steatosis in absence of secondary causes for steatosis. Skeletal muscle index (SMI) was defined as appendicular lean mass/height2 and (pre)sarcopenia was defined using the European Working Group on Sarcopenia in Older People (EWGSOP) consensus guidelines. All analyses were stratified by sex and BMI (cut point: 25 kg/m2) and adjusted for age, weight, height, homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides, and android-fat-to-gynoid-fat ratio (AGR). We included 4609 participants, of whom 1623 had NAFLD (n = 161 normal-weight and n = 1462 overweight). Presarcopenia and sarcopenia prevalence was low (5.9% and 4.5%, respectively) and both were not associated with NAFLD. SMI was associated with less NAFLD in normal-weight women (OR, 0.48; 95% CI, 0.29 to 0.80). A similar association for SMI and NAFLD was seen in normal-weight men, but significance dissipated after adjustment for AGR (OR, 0.63; 95% CI, 0.39 to 1.02). Generally, fat mass was a better predictor for NAFLD than lean mass. In particular, android fat mass was associated with all NAFLD subgroups (OR from 1.77 in overweight men to 8.34 in normal-weight women, pmax = 0.001), whereas substitution of gynoid fat mass for other body components had a significant protective association with NAFLD in every subgroup, but normal-weight men. Likewise, AGR was the best performing predictor for NAFLD prevalence (OR from 1.97 in normal-weight men to 4.81 in normal-weight women, pmax < 0.001). In conclusion, both high fat mass and low SMI were associated with normal-weight NAFLD. However, fat distribution (as assessed by AGR) could best predict NAFLD prevalence. © 2019 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals, Inc.  相似文献   
56.
57.
Background: We questioned whether differences in psychopathological status and interpersonal relations exist in a group of morbidly obese patients 18 months after bariatric surgery,as related to extent of weight loss. Methods: The study group consisted of 100 morbidly obese patients (85 female, 15 male) who had undergone surgical treatment (vertical banded gastroplasty) for weight reduction. Each patient completed the Lancashire Quality of Life Profile - European version, the Eating Disorder Inventory,the Symptom Check List-90-Revised, and the Millon Clinical Multiaxial Inventory-II. The sample was divided into 2 groups according to the percentage of excess weight loss 18 months after surgery: a greater weight loss group (weight loss >30%) and a lesser weight loss group (weight loss <30%). Results: Significant differences were found between the 2 groups in percentage of weight loss (P<0.0001), negative self-esteem (P<0.001), drive for thinness (P<0.001), body dissatisfaction (P<0.001), global EDI (P<0.002), anxiety (P<0.003), GSI (P<0.002), avoidant (P<0.001), borderline (P<0.0001), and passive-aggressive (P<0.002). Conclusion: Greater weight loss strongly correlates with improved quality of life, less disturbed eating behavior, and lower psychopathology. These results justify the clinical use of surgical procedures and demonstrate that weight loss has powerful psychological and psychosocial implications.  相似文献   
58.
Background: The current attitudes among European bariatric surgeons toward the laparoscopic bariatric operations were examined. Methods: 150 questionnaires were sent to recognized bariatric surgeons in Europe, and 60% responded. Results: 47% of respondents perform laparoscopic Roux-en-Y gastric bypass (LRYGBP), 81% laparoscopic adjustable gastric banding (LAGB), and 29% laparoscopic biliopancreatic diversion with or without duodenal switch (L-BPD/BPDDS). For BMI <40, 57% of respondents would only perform LAGB, 7% LRYGBP, 2% vertical banded gastroplasty (VBG), 3% L-BPD/BPDDS, and 2% intra-gastric balloon. For BMI 40-50, 43% of respondents prefer LAGB, 11% LRYGBP, 8% VBG, 5% L-BPD/BPDDS, and 33% contemplate several operations. For BMI 50-60, 30% prefer LAGB, 23% LRYGBP, 5% VBG, 16% L-BPD/BPDDS, and 26% tailor each patient's treatment. For BMI >60, 20% prefer LAGB, 24% LRYGBP, 37% L-BPD/BPDDS, 2% VBG, and 17% consider more than one operation. Although important, BMI and patient eating habits are not significant in choosing an operation for 25% of respondents. Interestingly, 39% of the surgeons offer laparoscopic bariatric surgery to so-called pediatric patients (<18). Of these, 76% favor LAGB, 8% LRYGBP, 8% L-BPD and 4% other procedures. Conclusions: The overall body of respondents prefers laparoscopic procedures. The responses suggest that at lower BMI there is a higher trend for restrictive operations. However, as BMI increases, combined and malabsorptive operations are preferred. At least one-third of surgeons offer bariatric surgery to patients with age <18 years, and here LAGB is greatly preferred.  相似文献   
59.
Background: Obesity is frequently associated with metabolic and cardiovascular co-morbidities and high mortality rates. Besides, because of the increasingly recognized fact that conservative therapy for morbid obesity is associated with an almost 90-95% failure rate in the long term, and probably because of the development of laparoscopic surgery,the demand for bariatric surgery is increasing rapidly.The significant weight loss observed during the first 6-12 months after gastric banding is related to the severe food restriction, related hypercatabolism, and has a potential risk of mineral and vitamin deficiencies.The aim of this study was to evaluate the effects of gastric banding on total body composition, metabolic profile and nutritional status. Methods: 31 women were studied with median age 36 years (range 25-52), body weight 118.6 kg (range 98-156), BMI 43.6 kg/m2 (range 36-56 kg/m2), percentage of excess body weight (%EW) of 107% (range 72- 166%), waist 115 cm (range 98-132) and hip 138 cm (range 119-155). Total body composition was measured before, 6 and 12 months after laparoscopic gastric banding, using dual-energy x-ray absorptiometry. Metabolic and nutritional profile were evaluated before and 1, 3, 6, 9 and 12 months postoperatively. Results: There was a 23.3% reduction of total body weight and 36.8% reduction of body fat. Unfortunately we also observed a reduction of Fat Free Mass (FFM) of 9.6%. In addition, the major determinants of weight loss were the initial body weight and abdominal distribution of fat mass. Reduction of FFM was positively correlated with the rapidity of weight loss. A significant improvement of glucidic profile was observed, with disappearance of impaired fasting glucose, and normalization of the values of triglycerides in all patients. The prevalence of the metabolic syndrome decreased from 89% in preoperative conditions to 15% 1 year after gastric banding. No major nutritional deficiencies was found following gastric banding. Conclusions: This prospective study suggests that the first 6 months postoperatively are crucial for weight loss and changes in body composition. Furthermore, the significant reduction of body weight is accompanied by an important improvement of biological abnormalities.  相似文献   
60.
This study investigated the impact of body dissatisfaction and binge eating on self-esteem in women with Type II diabetes. The relationship of body dissatisfaction and bingeing to perceived blood glucose control was also assessed. Questionnaires were completed by a total of 215 women: 125 women with Type II diabetes and 90 comparison women, who were roughly matched for age, education, and ethnicity. When actual weight (BMI) was statistically controlled, there was no difference between the groups in body dissatisfaction or bingeing behavior. The women with diabetes, however, had significantly lower self-esteem. Further, bingeing made a significant contribution to their self-esteem, in contrast to the women without diabetes. For the women with diabetes, body dissatisfaction and bingeing were also related to perceived blood glucose control, although only bingeing remained significant when both variables were entered into the regression equation. It was concluded that diabetes broadens the domains of body dissatisfaction which are related to self-esteem.  相似文献   
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