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Several epidemiological studies showed that gestational diabetes mellitus is the most frequent metabolic disorder of pregnancy, the pathogenesis of which has yet to be completely clarified. The aim of this study was to investigate the presence and processing of caspase 3 (Casp3) and poly(ADP‐ribose) polymerase 1 (PARP1) in cord blood lymphocytes as markers of apoptosis in relation to glycaemic control during intrauterine life. Our results showed a specific positive correlation between the levels of active Casp3 (17–19 kDa) and the inactive form of PARP1 (89 kDa) in lymphocytes isolated from newborn babies of diabetic women with unbalanced glycaemic control, with a direct correlation between the activation of casp3 and the inactivation of PARP1, that makes lymphocytes unresponsive towards lipopolysaccharide stimulation, highlighting an altered functional response. Besides more studies are required to fully correlate the activation of the apoptotic process during the intrauterine life with the foetal health later in life, our study indicates that a cord blood lymphocyte, an easily accessible source, is informative about the activation of apoptotic stimuli in circulating cells of newborn babies in relation to the glycaemic control reached by the mother during pregnancy. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Introduction: Human serum albumin (HSA) is a multifaceted protein with vital physiological functions. It is the most abundant plasma protein with inherent capability to bind to diverse ligands, and thus susceptible to various post-translational modifications (PTMs) which alter its structure and functions. One such PTM is glycation, a non-enzymatic reaction between reducing sugar and protein leading to formation of heterogeneous advanced glycation end products (AGEs). Glycated albumin (GA) concentration increases significantly in diabetes and is implicated in development of secondary complications.

Areas covered: In this review, we discuss in depth, formation of GA and its consequences, approaches used for characterization and quantification of GA, milestones in GA proteomics, clinical relevance of GA as a biomarker, significance of maintaining abundant levels of albumin and future perspectives.

Expert commentary: Elevated GA levels are associated with development of insulin resistance as well as secondary complications, in healthy and diabetic individuals respectively. Mass spectrometry (MS) based approaches aid in precise characterization and quantification of GA including early and advanced glycated peptides, which can be useful in prediction of the disease status. Thus GA has evolved to be one of the best candidates in the pursuit of diagnostic markers for prediction of prediabetes and diabetic complications.  相似文献   

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为了提高P277肽抗1型糖尿病的作用, 把P277肽融合在卡介苗热休克蛋白65的C端, 构建了pET28a- HSP65-P277高效表达载体, 在大肠杆菌中高效可溶性表达。利用硫酸铵分级沉淀、阴离子交换柱层析分离纯化了融合蛋白HSP65-P277。使用HSP65-P277在没有任何佐剂存在的情况下免疫非肥胖性糖尿病(NOD)小鼠, 通过三次腹腔注射, 每月收集被免疫动物的血清, 血糖浓度用自动生化分析仪测定。结果显示HSP65-P277免疫组小鼠血糖平均值及糖尿病的累积发病率和其余组相比均有显著差异(P<0.01), 融合蛋白HSP65-P277抗NOD小鼠糖尿病的作用显著高于单独的P277和HSP65。为进一步开发能用于临床的1型糖尿病疫苗提供了良好的设计思路, HSP65-P277极有可能进一步发展成为新的抗I型糖尿病的疫苗。  相似文献   
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Background and objectiveSince ancient times, honey has been used due to its nutritional and therapeutic value. The role of honey has been acknowledged in the scientific literature however, its use has been controversially discussed and has not been well accepted in modern medicine especially for diabetic patients. This study aimed to investigate the role of honey in diabetic patients.MethodsIn this study, we identified 107 research articles from data based search engines including “PubMed”, “ISI-Web of Science”, “Embase” and “Google Scholar”. The research papers were selected by using the primary key-terms including “Honey”, “Honey bee” and “Diabetes Mellitus”. The research documents in which “Honey” and “Diabetes Mellitus” were debated are included. After screening, we reviewed 66 papers and finally we selected 35 studies which met the inclusion criteria and the remaining documents were excluded.ResultsThis study investigated the preclinical, clinical, human and animal model studies on honey and diabetes mellitus and found that honey decreases the fasting serum glucose, increases the sting C-peptide and 2-h postprandial C-peptide. Although, there is a dearth of data and literature also contrary discussed the use of honey in diabetic patients.ConclusionHoney decreases the fasting serum glucose, increases fasting C-peptide and 2-h postprandial C-peptide. Honey had low glycemic index and peak incremental index in diabetic patients. The use of honey in diabetic patients still has obstacles and challenges and needs more large sample sized, multi-center clinical controlled studies to reach better conclusions.  相似文献   
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We report the discovery of the glucose-dependent insulin secretogogue activity of a novel class of polycyclic guanidines through phenotypic screening as part of the Lilly Open Innovation Drug Discovery platform. Three compounds from the University of California, Irvine, 13, having the 3-arylhexahydropyrrolo[1,2-c]pyrimidin-1-amine scaffold acted as insulin secretagogues under high, but not low, glucose conditions. Exploration of the structure–activity relationship around the scaffold demonstrated the key role of the guanidine moiety, as well as the importance of two lipophilic regions, and led to the identification of 9h, which stimulated insulin secretion in isolated rat pancreatic islets in a glucose-dependent manner.  相似文献   
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The number of glucose molecules condensed on glycated bovine serum albumin have been easily determined by means of matrix-assisted laser desorption/ionization mass spectrometry. Measurements were carried out on samples from incubation of the proteins with glucose at different concentrations (0.02 M, 0.2 M, 2 M and 5 M). A clear increase in molecular mass of BSA with respect to incubation time is detected. In contrast to what is observed with fluorescence, the plots of molecular mass increase vs. incubation time show tha occurrence of a steady state, corresponding to the complete saturation of all the protein sites against glucose. Comparison of fluorescence and molecular mass data reveals that some further reactions, different from condensation, must take place, which could be in principle either intramolecular or originated by reactivity of modified condensed gluocse moieties vs. free glucose.  相似文献   
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This study was designed to determine if the known decrease in slow axonal transport of proteins in the sciatic nerve of experimentally diabetic rats is related to altered phosphorylation of neurofilament proteins (NFPs). Rats were rendered diabetic with 50 mg/kg of streptozotocin, i.p. At 3 and 6 weeks later, NFPs were prepared from spinal cord. The in vivo phosphorylation state of NFPs was examined by using phosphate-dependent (RT97) and -independent (RMd09) antibodies against high-molecular-mass NFPs on Western blots. Neurofilament-associated kinase activity was also measured in vitro by incubation of NFPs with [32P]ATP. Phosphorylation of all three NFPs (high, medium, and low molecular mass) occurred, as confirmed by gel electrophoresis and autoradiography. At 30 min of incubation, protein-bound radioactivity in NFPs from diabetic animals was reduced to 86.7 +/- 3.4 and 54.3 +/- 19.6% of that in nondiabetic animals at 3 and 6 weeks of diabetes, respectively (p less than 0.001 and p less than 0.05, respectively). NFPs were also incubated with acid phosphatase and rephosphorylated. Results showed that the increased in vivo phosphorylation contributed to the decreased in vitro phosphorylation. Extraction of protein kinases and addition back to the NFPs revealed, in addition, a reduced activity in the diabetic animals of the protein kinases measured in vitro.  相似文献   
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Twenty-five derivatives of 5-chloro-2-aryl benzo[d]thiazole (125) were synthesized and evaluated for their α-glucosidase (S. cerevisiae EC 3.2.1.20) inhibitory activity in vitro. Among them eight compounds showed potent activity with IC50 values between 22.1 ± 0.9 and 136.2 ± 5.7 μM, when compared with standard acarbose (IC50 = 840 ± 1.73 μM). The most potent compounds 4, 9, and 10 showed IC50 values in the range of 22.1 ± 0.9 to 25.6 ± 1.5 μM. Compounds 2, 5, 11, and 19 showed IC50 values within the range of 40.2 ± 0.5 to 60.9 ± 2.0 μM. Compounds 1 and 3 were also found to be good inhibitors with IC50 values 136.2 ± 5.7 and 104.8 ± 9.9 μM, respectively. Their activities were compared with α-glucosidase inhibitor drug acarbose (standard) (IC50 = 840 ± 1.73 μM). The remaining compounds were inactive. Structure-activity relationships (SAR) have also been established. Kinetics studies indicated compounds 2, 3, 10, 19, and 25 to be non-competitive, while 1, 5, 9, and 11 as competitive inhibitors of α-glucosidase enzyme. All the active compounds (15, 911, and 19) were also found to be non-cytotoxic, in comparison to the standard drug i.e., doxorubicin (IC50 = 0.80 ± 0.12 μM) in MTT assay. Furthermore, molecular interactions of active compounds with the enzyme binding sites were predicted through molecular modeling studies.  相似文献   
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目的:比较药物洗脱支架(DES)植入术及冠状动脉旁路移植术(CABG)治疗冠心病多支病变伴糖尿病患者的近期及远期临床疗效。方法:回顾性分析2014年1月~2016年10月在哈尔滨医科大学附属第一医院经冠状动脉造影证实为多支血管病变并伴有糖尿病的患者186例,根据血运重建方式的不同分为DES组及CABG组,随访50.5±14.3个月,观察两组患者住院期间及随访期主要不良心脑血管事件(包括非致死心肌梗死、脑卒中、再次血运重建、全因死亡)的发生情况。结果:在所有入选患者中,DES组有更多双支病变(P0.05),CABG组三支病变较多(P0.05),两组在完全血运重建方面无显著性差异(P0.05)。住院期间,CABG组死亡2例(2.3%),DES组死亡1例(1.0%),死亡率比较无统计学意义(P0.05)。两组均未出现非致死性心肌梗死、脑卒中、再次血运重建。出院后对186例入选患者随访,其中失访11例(DES组5例,CABG组6例)。随访期间CABG组发生非致死性心肌梗死1例(1.3%)、脑卒中6例(7.5%)、全因死亡10例(12.5%),DES组发生非致死性心肌梗死5例(5.3%)、脑卒中3例(3.2%)、全因死亡9例(9.5%),两组间比较差异无统计学意义(P0.05);而CABG组再次血运重建2例(2.5%),DES组15例(15.8%),两组比较差异具有统计学意义(P0.01)。结论:行DES置入术或CABG术治疗冠心病多支病变伴糖尿病患者,住院期间主要心脑血管不良事件发生率、远期非致死性心肌梗死、脑卒中、全因死亡发生情况均无显著性差异,但DES组再次血运重建率明显升高,可能与糖尿病患者较高的再狭窄率有关。  相似文献   
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