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Ren D.,Qingdao University | Sun K.,Qingdao University | Tian S.,Qingdao University | Yang X.,Qingdao University | And 5 more authors.
Journal of Biomechanics | Year: 2012

An increasing number of tissue banks have begun to focus on gamma irradiation and freeze-thaw in the reconstruction of anterior cruciate ligaments using allografts. The purpose of this study was to evaluate the biomechanical properties of human tendons after exposure to gamma radiation and repeated freeze-thaw cycles and to compare them with fresh specimens. Forty flexor digitorum superficialis tendons were surgically procured from five fresh cadavers and divided into four groups: fresh tendon, gamma irradiation, freeze-thaw and gamma irradiation+freeze-thaw. The dose of gamma irradiation was 25. kGy. Each freeze-thaw cycle consisted of freezing at -80°C for 7 day and thawing at 25°C for 6. h. These tendons underwent 4 freeze-thaw cycles. Biomechanical properties were analyzed during load-to-failure testing. The fresh tendons were found to be significantly different in ultimate load, stiffness and ultimate stress relative to the other three groups. The tendons of the gamma+freeze-thaw group showed a significant decrease in ultimate load, ultimate stress and stiffness compared with the other three groups. Gamma irradiation and repeated freezing-thawing (4 cycles) can change the biomechanical properties. However, no significant difference was found between these two processes on the effect of biomechanical properties. It is recommended that gamma irradiation (25. kGy) and repetitive freeze-thaw cycles (4 cycles) should not be adopted in the processing of the allograft tendons. © 2011 Elsevier Ltd. Source

Xu M.,Harvard University | Xu M.,Shanghai Institute of Endocrine and Metabolic Diseases | Xu M.,Shanghai JiaoTong University | Qi Q.,Harvard University | And 5 more authors.
Circulation | Year: 2013

Background-Circulating branched-chain amino acids and aromatic amino acids were recently related to insulin resistance and diabetes mellitus in prospective cohorts. We tested the effects of a genetic determinant of branched-chain amino acid/ aromatic amino acid ratio on changes in body weight and insulin resistance in a 2-year diet intervention trial. Methods and Results-We genotyped the branched-chain amino acid/aromatic amino acid ratio-associated variant rs1440581 near the PPM1K gene in 734 overweight or obese adults who were assigned to 1 of 4 diets varying in macronutrient content. At 6 months, dietary fat significantly modified genetic effects on changes in weight, fasting insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) after adjustment for the confounders (all P for interaction ≤0.006). Further adjustment for weight change did not appreciably change the interactions for fasting insulin and HOMA-IR. In the highfat diet group, the C allele was related to less weight loss and smaller decreases in serum insulin and HOMA-IR (all P ≤ 0.02 in an additive pattern), whereas an opposite genotype effect on changes in insulin and HOMA-IR was observed in the low-fat diet group (P=0.02 and P=0.04, respectively). At 2 years, the gene-diet interactions remained significant for weight loss (P=0.008) but became null for changes in serum insulin and HOMA-IR resulting from weight regain. Conclusions-Individuals carrying the C allele of the branched-chain amino acid/aromatic amino acid ratio-associated variant rs1440581 may benefit less in weight loss and improvement of insulin sensitivity than those without this allele when undertaking an energy-restricted high-fat diet. © 2013 American Heart Association, Inc. Source

Qiu M.,Shanghai Institute of Endocrine and Metabolic Diseases | Shen W.,Shanghai Institute of Hypertension | Song X.,Shanghai JiaoTong University | Song X.,Tongji University | And 8 more authors.
Hypertension | Year: 2015

Whether prediabetes mellitus alone or combined with other disorders means a higher risk for cardiovascular disease (CVD) is still controversial. This study aimed to investigate the association between prediabetes mellitus and CVD and diabetes mellitus and to explore whether prediabetes mellitus alone or combined with other syndromes, such as hypertension, could promote CVD risks significantly. This longitudinal population-based study of 1609 residents from Shanghai in Southern China was conducted between 2002 and 2014. Participants with a history of CVD at baseline were excluded from analysis. Multivariate log-binomial regression models were used to adjust possible coexisting factors. Incidence of CVD during follow-up was 10.1%. After adjusting for age, sex, and other factors, the association between prediabetes mellitus and CVD was not observed. When hypertension was incorporated in stratifying factors, adjusted CVD risk was elevated significantly (odds ratio, 2.41; 95% confidence interval, 1.25-4.64) in prediabetes mellitus and hypertension combined group, and coexistence of diabetes mellitus and hypertension made CVD risk highly significantly increased, reaching 3.43-fold higher than the reference group. Blood glucose level within prediabetic range is significantly associated with elevated risks for diabetes mellitus after multivariable adjustment, but only when it is concurrent with other disorders, such as hypertension, it will significantly increase CVD risk. © 2015 American Heart Association, Inc. Source

Chowdhury S.,Fraser Laboratories for Diabetes Research | Wang X.,Shanghai Institute of Endocrine and Metabolic Diseases | Srikant C.B.,Fraser Laboratories for Diabetes Research | Li Q.,Fraser Laboratories for Diabetes Research | And 5 more authors.
Endocrinology | Year: 2014

IGF-I is normally produced from hepatocytes and other sources, stimulates protein synthesis, cell survival, and proliferation through receptor-mediated activation of phosphatidylinositol 3-kinase and MAPK, and targets specific molecules within the pancreatic islet cells. The current study was designed to identify novel targets that may mediate its pro-islet actions. Whole-genome cDNA microarray analysis in IGF-I-overexpressing islets identified 82 genes specifically up- or downregulated. Prominent among them was CCN5/WISP2 whose expression was increased 3- and 2-fold at the mRNA and protein levels. Dual-labeled immunofluorescence revealed that CCN5 expression was low in the β-cells of wild-type islets but was significantly induced in response to IGF-I overexpression. In vitro treatment of mouse islets with IGF-I increased both CCN5 mRNA and protein levels significantly. To define the role of CCN5 in islet cell biology,westably overexpressed its cDNA in insulinoma MIN6 cells and detected a 2-fold increase in the proliferation of MIN6-CCN5 compared with that in control cells, which correlated with significant elevations in the levels of cyclin D1andthe phosphorylation of AktandErk2. Moreover,MIN6-CCN5cells were found to be resistant to streptozotocin-induced cell death. Using confocal microscopy and subcellular fractionation, we found that overexpressed CCN5 exhibited cytoplasmic accumulation upon stimulation by high glucose. Our results indicate that CCN5, which is minimally expressed in islet βcells, is strongly and directly induced by IGF-I. CCN5 overexpression stimulates the proliferation of insulinoma cells, activates Akt kinase, and inhibits streptozotocin-induced apoptosis, suggesting that increased CCN5 expression contributes to IGF-I-stimulated islet cell growth and/or survival. © 2014 by the Endocrine Society. Source

Wu Y.-C.,Shanghai JiaoTong University | Su T.-W.,Shanghai Institute of Endocrine and Metabolic Diseases | Su T.-W.,Shanghai JiaoTong University | Zhang J.-F.,Shanghai JiaoTong University | And 4 more authors.
Journal of Diabetes | Year: 2015

Background: A comprehensive meta-analysis was performed to evaluate the comparative benefits of coronary artery bypass grafting (CABG) versus drug-eluting stents (DES) in patients with diabetes mellitus and severe coronary artery disease (CAD). Methods: A comprehensive literature search of PubMed, Embase, and ScienceDirect was undertaken. References cited with the papers were also checked to identify relevant articles. Results: In all, four randomized controlled trials, two prospective registries, and 11 retrospective studies were identified for review. Pooled analysis demonstrated that DES was associated with lower all-cause mortality at Day 30. However, there was no significant difference between CABG and DES in mortality at 12 months and at maximum follow-up. Furthermore, DES was associated with lower overall and major adverse cardiac and cerebrovascular events (MACCE)-free survival, as well as a higher incidence of myocardial infarction and repeat revascularization. In contrast, CABG was associated with an increased risk of stroke. Conclusions: For patients with diabetes mellitus and severe CAD, CABG is superior to DES in that it significantly improves overall and MACCE-free survival and reduces the incidence of myocardial infarction and repeat revascularization in the long term, although it is associated with greater perioperative risk and a higher incidence of stroke. Therefore, CABG should remain the gold standard for these patients. © 2014 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd. Source

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