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Patients and methods
Chronic adductor-related groin pain in athletes is debilitating and is often challenging to treat. Little is published on the surgical treatment when conservative measures fail. This single center study reviews the outcomes of 48 patients (68 groins) who underwent percutaneous adductor tenotomy for sports-related chronic groin pain. Questionnaire assessments were made preoperatively and at a minimum follow-up of 25 months. 相似文献OBJECTIVE
C57Bl/6 mice develop obesity and mild hyperglycemia when fed a high-fat diet (HFD). Although diet-induced obesity (DIO) is a widely studied model of type 2 diabetes, little is known about β-cell failure in these mice.RESEARCH DESIGN AND METHODS
DIO mice were separated in two groups according to body weight gain: low- and high-HFD responders (LDR and HDR). We examined whether mild hyperglycemia in HDR mice is due to reduced β-cell mass or function and studied islet metabolism and signaling.RESULTS
HDR mice were more obese, hyperinsulinemic, insulin resistant, and hyperglycemic and showed a more altered plasma lipid profile than LDR. LDR mice largely compensated insulin resistance, whereas HDR showed perturbed glucose homeostasis. Neither LDR nor HDR mice showed reduced β-cell mass, altered islet glucose metabolism, and triglyceride deposition. Insulin secretion in response to glucose, KCl, and arginine was impaired in LDR and almost abolished in HDR islets. Palmitate partially restored glucose- and KCl-stimulated secretion. The glucose-induced rise in ATP was reduced in both DIO groups, and the glucose-induced rise in Ca2+ was reduced in HDR islets relatively to LDR. Glucose-stimulated lipolysis was decreased in LDR and HDR islets, whereas fat oxidation was increased in HDR islets only. Fatty acid esterification processes were markedly diminished, and free cholesterol accumulated in HDR islets.CONCLUSIONS
β-Cell failure in HDR mice is not due to reduced β-cell mass and glucose metabolism or steatosis but to a secretory dysfunction that is possibly due to altered ATP/Ca2+ and lipid signaling, as well as free cholesterol deposition.While insulin resistance is a common feature in most obese subjects, insulin secretion is increased to compensate for its reduced action and normoglycemia is maintained (1,2). In obese type 2 diabetes subjects, however, β-cell compensation fails due to marked impairment of glucose-stimulated insulin secretion (GSIS), often with reduced β-cell mass (2). The relationship between β-cell function and mass as causative factors in β-cell failure and diabetes progression is debated, with emphasis on the relevance of “functional β-cell mass” rather than total mass (2). Increased adiposity leads to elevated circulating free fatty acids (FFAs) and triglycerides, and in vitro and in vivo studies have indicated a causative role for dyslipidemia in insulin resistance (1,3). Although FFAs are necessary for the amplification of GSIS, their excess supply may also have a role in β-cell failure (4), as prolonged elevation of FFA levels both in vivo and in vitro cause β-cell dysfunction (5,6) and, at least in vitro, apoptosis (7).At least part of the β-cell compensation to insulin resistance is due to an increase in β-cell mass (4). Either long-term high-fat diet (HFD) (8) or a short-term lipid infusion (9) can result in increased β-cell mass without augmentation of GSIS, indicating that β-cell function and mass are not necessarily linked. Rodent studies have indicated that HFD leads to increased β-cell mass (8), which is also observed in normoglycemic obese individuals (10). Unclear at present is the dynamics between the factors driving compensatory increase in β-cell mass and function and those reducing them through the various stages of type 2 diabetes development, particularly as FFA may do both. Genetic islet susceptibility may be a critical determinant of these dynamics, both in humans and animal models (4,11,12).Even though studies employing genetically modified models (e.g., Zucker Diabetic Fatty rats, db/db mice) have helped in understanding some of these pathological processes (13–16), several of these models are of extreme nature, with rapid development of pronounced type 2 diabetes. These models, therefore, differ from human obesity-linked type 2 diabetes, which usually develops more gradually. In an attempt to gain insight into the basis of β-cell failure in a mild model of diabetes, we recently developed a new model of type 2 diabetes, the 60% pancreatectomized obese hyperlipidemic Zucker Fatty rat (14). In this model, severe β-cell dysfunction was found without any evidence of a falling β-cell mass or islet steatosis (14). More detailed examination of the pancreatectomized Zucker Fatty rat islets showed marked depletion of insulin stores and altered glycerolipid metabolism (14). The Zucker Fatty rat, as opposed to the Zucker Diabetic Fatty rat, however, does not have genetic predisposition to diabetes, as it maintains normoglycemia despite severe obesity-related insulin resistance (4). The diet-induced obese (DIO) C57BL/6 mouse gradually develops hyperglycemia (17). This suggests that DIO islets are unable to fully compensate for the obesity-related insulin resistance, as occurs in human type 2 diabetes.In the present study, we investigated β-cell dysfunction in DIO mice stratified into two groups according to the effect of HFD on body weight: the low responders to HFD (LDR) were less obese, developed intermediate severity of insulin resistance, and had only mild impairment in glycemia. The high responders to HFD (HDR) were more obese, insulin resistant, and hyperinsulinemic and were clearly hyperglycemic. Thus, the LDR and HDR groups allowed for analysis and comparison of islet β-cell mass and function in response to different levels of insulin resistance with corresponding very mild perturbation of glucose homeostasis and overt but mild hyperglycemia, respectively. When extended to obese humans, these two groups correspond to the pre-diabetes and early diabetes situations. 相似文献OBJECTIVE
Several single nucleotide polymorphisms (SNPs) in diabetes risk genes reduce glucose- and/or incretin-induced insulin secretion. Here, we investigated interactions between glycemia and such diabetes risk polymorphisms.RESEARCH DESIGN AND METHODS
Insulin secretion was assessed by insulinogenic index and areas under the curve of C-peptide/glucose in 1,576 subjects using an oral glucose tolerance test (OGTT). Participants were genotyped for 10 diabetes risk SNPs associated with β-cell dysfunction: rs5215 (KCNJ11), rs13266634 (SLC30A8), rs7754840 (CDKAL1), rs10811661 (CDKN2A/2B), rs10830963 (MTNR1B), rs7903146 (TCF7L2), rs10010131 (WFS1), rs7923837 (HHEX), rs151290 (KCNQ1), and rs4402960 (IGF2BP2).Furthermore, the impact of the interaction between genetic variation in TCF7L2 and glycemia on changes in insulin secretion was tested in 315 individuals taking part in a lifestyle intervention study.RESULTS
For the SNPs in TCF7L2 and WFS1, we found a significant interaction between glucose control and insulin secretion (all P ≤ 0.0018 for glucose × genotype). When plotting insulin secretion against glucose at 120 min OGTT, the compromising SNP effects on insulin secretion are most apparent under high glucose. In the longitudinal study, rs7903146 in TCF7L2 showed a significant interaction with baseline glucose tolerance upon change in insulin secretion (P = 0.0027). Increased glucose levels at baseline predicted an increase in insulin secretion upon improvement of glycemia by lifestyle intervention only in carriers of the risk alleles.CONCLUSIONS
For the diabetes risk genes TCF7L2 and WFS1, which are associated with impaired incretin signaling, the level of glycemia determines SNP effects on insulin secretion. This indicates the increasing relevance of these SNPs during the progression of prediabetes stages toward clinically overt type 2 diabetes.Type 2 diabetes is a disorder characterized by chronically elevated blood glucose levels due to insulin resistance and a relative lack of compensatory pancreatic insulin secretion. Environmental triggers such as a sedentary lifestyle, physical inactivity, and increased body weight play an important role in the development of the disease. In this regard, genetics and especially gene-environment interactions play an important role. Recent research revealed more than 25 gene variants leading to a higher risk for the development of type 2 diabetes (1). Interestingly, most of the diabetes risk genes alter β-cell function (1). This supports the hypothesis that the main genetic effect in the development of type 2 diabetes could be impaired insulin secretion. Neither environmental triggers nor genetics alone can explain the multifactorial disease type 2 diabetes, thus a close interaction between both is presumed (2–4). Hence, environmental influences may determine an individual''s susceptibility for single nucleotide polymorphism (SNP) effects, or vice versa genotype may designate a person''s susceptibility toward environmental factors.One “environmental” factor that plays a role early in the pathogenesis of type 2 diabetes is elevated glucose. It is well known that years before type 2 diabetes occurs, glucose control is altered, as reflected by higher fasting glucose and/or higher postprandial glucose (5). High glucose exerts unfavorable effects on insulin sensitivity and secretion, known as glucotoxicity (6,7). On the other hand, elevated glucose levels are needed for the incretin effect. Glucagon-like peptide 1–induced insulin secretion becomes fully active only in the hyperglycemic range (8,9). Incretin-dependent insulin secretion might therefore be of particular importance when compensatory insulin hypersecretion is required.The aim of this study was to investigate whether glycemia influences the effects of genetic variation associated with type 2 diabetes on insulin secretion. We therefore studied 10 genome-wide association study–derived variants that were furthermore found to influence β-cell function in subsequent studies (rev. in 1,10). Of these, 2 (in the TCF7L2 and WFS1 loci) are associated with incretin-stimulated insulin secretion (1). As the magnitude of incretin-stimulated insulin secretion is dependent on elevated glucose levels (8,9), we hypothesized that glucose levels specifically interact with the effect of those SNPs on insulin secretion both in cross-sectional and longitudinal intervention studies. 相似文献Methods: With approval of the local animal care committee, microdialysis probes with attached microtubing for sevoflurane injection were placed in the adductor muscles of nine MHS and six MHN pigs, and Pco2 probes with microtubing were positioned in the triceps muscle of eight MHS and six MHN pigs. After equilibration, sevoflurane boluses at different concentrations and a sevoflurane-dantrolene bolus were injected synchronously. Lactate, pyruvate, and glucose as well as Pco2 were measured spectrophotometrically, and the rate of Pco2 increase was calculated.
Results: Intramuscular sevoflurane injection increased local lactate and Pco2 dose dependently, and significantly higher in MHS than in MHN pigs. Measurement of the rate of Pco2 increase allowed a distinct differentiation between single MHS and MHN pigs. No significant increase in Pco2 was found with sevoflurane and dantrolene. 相似文献
Methods: The authors performed a double-blinded, placebo-controlled, multicenter trial to compare the effect of bisoprolol with that of placebo on 1-yr composite outcome including cardiovascular mortality, nonfatal myocardial infarction, unstable angina, congestive heart failure, and cerebrovascular insult. Bisoprolol was given orally before and after surgery for a maximum of 10 days. Adrenergic receptor polymorphisms and safety outcome measures of bisoprolol therapy were also determined.
Results: A total of 224 patients were enrolled. Spinal block could not be established in 5 patients. One hundred ten patients were assigned to the bisoprolol group, and 109 patients were assigned to the placebo group. The mean duration of treatment was 4.9 days in the bisoprolol group and 5.1 days in the placebo group. Bisoprolol therapy reduced mean heart rate by 10 beats/min. The primary outcome was identical between treatment groups and occurred in 25 patients (22.7%) in the bisoprolol group and 24 patients (22.0%) in the placebo group during the 1-yr follow-up (hazard ratio, 0.97; 95% confidence interval, 0.55-1.69; P = 0.90). However, carriers of at least one Gly allele of the [beta]1-adrenergic receptor polymorphism Arg389Gly showed a higher number of adverse events than Arg homozygous (32.4% vs. 18.7%; hazard ratio, 1.87; 95% confidence interval, 1.04-3.35; P = 0.04). 相似文献