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The objective of this study was to examine relationships between impaired glucose tolerance (IGT) and body composition and insulin-related phenotypes in 150 overweight Latino children with a family history of type 2 diabetes. Glucose tolerance was assessed by an oral glucose challenge. Body composition was assessed by dual energy x-ray absorptiometry and magnetic resonance imaging. Insulin sensitivity, the acute insulin response, and the disposition index (DI), as an index of beta-cell function, were determined by an iv glucose tolerance test and compared between normal glucose-tolerant and IGT children. IGT was present in 28% of children, and was similar across obesity groups, but higher in children exposed to gestational diabetes mellitus (41% IGT). There were no significant differences in body composition, fat distribution, insulin sensitivity, or acute insulin response, but DI was significantly lower in IGT children by 16% (P < 0.02), and DI was inversely related to age. In conclusion, IGT is present in 28% of overweight Latino children with a family history of type 2 diabetes, is not influenced by obesity, is more prevalent in children exposed to gestational diabetes mellitus, and is related to poor beta-cell function, which shows signs of deterioration with age in this population.  相似文献   
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Whether use of hormone-replacement therapy (HRT) influences menopause-related changes in body weight is unclear. HRT may affect energy balance by influencing synthesis of the adipocyte-derived hormone leptin. The objectives of this study were to: 1) identify factors influencing circulating leptin in postmenopausal women; 2) determine whether HRT influences serum leptin after adjusting for confounding factors; and, 3) identify potential independent effects of HRT or leptin on resting energy expenditure (REE). Subjects were 54 postmenopausal women, 45-55 yr old, 35 of whom used HRT (estrogen plus progestin). Total and regional body composition and fat distribution were determined by dual-energy x-ray absorptiometry and computed tomography; fasting serum leptin and insulin, by RIA; and REE, by indirect calorimetry. Stepwise multiple linear regression analysis indicated that serum leptin could best be predicted from total fat mass, fasting serum insulin, and total lean mass [log leptin = 1.08 x log fat mass) + (0.46 x log insulin) + (-1.25 x log lean mass) + 1.88; model R2 = 0.78, P < 0.001]. Multiple linear regression analysis indicated that visceral fat was independently related to leptin (parameter estimate = 0.23, P < 0.05), after adjusting for s.c. abdominal fat and leg fat, as well as lean mass and insulin. After adjusting for total fat mass, total lean mass, and fasting insulin, serum leptin did not differ between users and nonusers of HRT (21.7 +/- 1.0 vs. 20.2 +/- 1.3 ng/mL, P = 0.369, adjusted mean +/- SE, respectively). Serum estradiol was inversely correlated with (adjusted) leptin in non-HRT users (r = -0.50), suggesting that ovarian senescence may lead to an increase in leptin. Multiple linear regression analysis indicated that REE (adjusted for fat mass, fat-free mass, and ethnicity) was not associated with leptin (P = 0.298) or hormone use status (P = 0.999; 1323 +/- 31 vs. 1316 +/- 42 kcal/day, adjusted mean +/- SE for users and nonusers, respectively). These results indicate that, in postmenopausal women: 1) total fat mass, lean mass, and fasting insulin, but not HRT, are significant determinants of serum leptin; 2) visceral and s.c. fat contribute to serum leptin; and, 3) neither HRT nor leptin is independently related to REE.  相似文献   
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ObjectivesAdequate hepatic arterial (HA) flow to the bile duct is essential in liver transplantation. This study was conducted to determine if the ratio of directly measured HA flow to weight is related to the occurrence of biliary complications after deceased donor liver transplantation.MethodsA retrospective review of 2684 liver transplants carried out over a 25-year period was performed using data sourced from a prospectively maintained database. Rates of biliary complications (biliary leaks, anastomotic and non-anastomotic strictures) were compared between two groups of patients with HA flow by body weight of, respectively, <5 ml/min/kg (n = 884) and ≥5 ml/min/kg (n = 1800).ResultsPatients with a lower ratio of HA flow to weight had higher body weight (92 kg versus 76 kg; P < 0.001) and lower HA flow (350 ml/min versus 550 ml/min; P < 0.001). A lower ratio of HA flow to weight was associated with higher rates of biliary complications at 2 months, 6 months and 12 months (19.8%, 28.2% and 31.9% versus 14.8%, 22.4% and 25.8%, respectively; P < 0.001).ConclusionsA ratio of HA flow to weight of < 5 ml/min/kg is associated with higher rates of biliary complications. This ratio may be a useful parameter for application in the prevention and early detection of biliary complications.  相似文献   
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Introduction

Acute coronary syndrome (ACS) is caused by destabilization and rupture of atherosclerotic plaque in the coronary artery via mechanisms affecting leukocyte signaling, rolling, adhesion, extravasation and inflammation-promoting factors. The majority of cellular communication takes place on the membrane surface that is covered with glycoproteins and glycolipids synthesized by glycosyltransferases. The aim of this study was to determine the mRNA expression of leukocyte adhesion-related glycosyltransferases in patients during the onset and the chronic phase of ACS and to compare the expression with matching subjects without coronary disease.

Subjects and methods

The study included 26 ACS patients and 26 ACS-free matched-pair controls. Blood samples were collected at the time of hospital admittance and 8 days later. Expression analysis of six fucosyltransferases and six sialyltransferases was performed by a real-time polymerase chain reaction.

Results

At the time of admittance ACS subjects had lower expression levels of FUT4, ST6GalNac4, ST6Gal1 and GM3 synthase (p < 0.05) than the control subjects, and moreover, after 8 days down-regulation of FUT7 and ST6GalNac3 was also observed (p < 0.05). When compared to the initial gene expression, after treatment and stabilization of ACS subjects, FUT7, ST6GalNac2 and ST6GalNac3 were down-regulated, whereas ST6GalNac1 was up-regulated. Expression levels of FUT7, ST6GalNac1, ST6GalNac2 and ST6GalNac3 were predicted by several drugs and medical history.

Conclusion

Expression of glycosyltransferase genes differs in ACS and control subjects. During the course of the ACS study we established further changes in gene expression levels. Medical history was predictive of gene expression levels while drugs were shown to modulate expression levels.  相似文献   
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ObjectiveAtrial fibrillation (AF) surveillance using a wireless handheld monitor capable of 12-lead electrocardiogram reconstruction was performed, and arrhythmia detection rate was compared with serial Holter monitoring.MethodsTwenty-five patients were monitored after an AF ablation procedure using the hand-held monitor for 2 months immediately after and then for 1 month approximately 6 months postablation. All patients underwent 12-lead 24-hour Holter monitoring at 1, 2, and 6 months postablation.ResultsDuring months 1-2, 425 of 2942 hand-held monitor transmissions from 21 of 25 patients showed AF/atrial flutter (Afl). The frequency of detected arrhythmias decreased by month 6 to 85/1128 (P < .01) in 15 of 23 patients. Holter monitoring diagnosed AF/Afl in 8 of 25 and 7 of 23 patients at months 1-2 and month 6, respectively (P < .01 compared with wireless hand-held monitor). Af/Afl diagnosis by wireless monitoring preceded Holter detection by an average of 24 days.ConclusionsWireless monitoring with 12-lead electrocardiogram reconstruction demonstrated reliable AF/Afl detection that was more sensitive than serial 12-lead 24-hour Holter monitoring.  相似文献   
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