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61.
2型糖尿病可能加重颈动脉斑块的易损性并增加缺血性中风的风险,关于2型糖尿病患者伴有颈动脉斑块特征的急性中风亚型鲜有研究报道。本研究旨在探讨2型糖尿病患者颈动脉斑块特征与MRI确定的急性脑梗死病变特征之间的关系。本研究以颈内动脉区急性脑血管病患者为研究对象,所有患者分为2型糖尿病组和非2型糖尿病组,分别行颈动脉和脑部MRI扫描,测定同侧颈动脉斑块的形态和特征,以及颅内和颅外颈动脉狭窄。基于中风亚型和急性脑梗塞病变模式对患者进行评估。研究结果表明,与非2型糖尿病患者相比,2型糖尿病患者颈动脉型IV-VI病变的患病率更高,斑块负荷更大,以及富脂质坏死核(LRNC)更大。在有症状的颈动脉LRNC患者中,与非2型糖尿病组相比,2型糖尿病组颈内动脉区出现较多的伴有大穿孔动脉梗塞形态和较大的急性脑梗塞。LRNC%>23.5%的颈动脉斑块是2型糖尿病患者存在颈动脉狭窄的急性脑梗塞病变的独立危险因素。颈动脉斑块特征的量化,尤其是MRI诊断的富脂质坏死核对中风风险具有潜在应用价值。  相似文献   
62.
An attempt has been made to compare the hypoglycemic effect of the organic constituents and the inorganic constituents in traditional Chinese medicine, Jinqi compound recipe. Alloxan-induced hyperglycemic mice were used in the study. The body weights, blood glucose, HbA1c, insulin secretion, and glycogen synthesis of the mice were analyzed respectively. After the mice were administered (oral) with organic constituents, the blood glucose and the HbA1c of alloxan-induced hyperglycemic mice decreased (p < 0.05, p < 0.01) and the glycogen synthesis of alloxan-induced hyperglycemic mice elevated (p < 0.05). Also, the body weight of the alloxan-induced hyperglycemic mice was increased gradually. However, the same result did not occur in the inorganic constituent-treated groups. It is noted that neither organic constituents nor inorganic constituents could elevate the level of serum insulin in the alloxan-induced hyperglycemic mice significantly. It is implied that the hypoglycemic effect for type 2 diabetes was caused by the organic constituents of Jinqi recipe. The results can be used to set new standards to control the quality of the Jinqi recipe.  相似文献   
63.
目的:探讨颈围用于筛选糖调节受损人群的临床价值。方法:选取哈尔滨市第一医院2017年3月至11月收治的糖调节受损患者共100例,男性颈围以38 cm为临界值,女性以35 cm为临界值,分为颈围正常组和颈围异常组,比较两组患者空腹及餐后血糖、空腹胰岛素、糖化血红蛋白、总胆固醇、甘油三酯、低密度脂蛋白等相关指标水平,并分析颈围与以上指标的相关性。结果:颈围异常组患者的餐后2 h血糖、空腹胰岛素、糖化血红蛋白、总胆固醇、甘油三酯、低密度脂蛋白数值高于颈围正常组,尤以甘油三酯明显,高密度脂蛋白数值低于颈围正常组,差异有统计学意义(P0.05)。颈围与餐后2 h血糖、总胆固醇、甘油三酯、低密度脂蛋白水平呈正相关,差异均有统计学意义(P0.05),颈围与高密度脂蛋白水平呈负相关,差异均有统计学意义(P0.05)。结论:颈围可以作为临床预测、评估糖调节受损患者的早期指标,为早期社区筛查及诊断提供相关的参考依据。  相似文献   
64.
A dynamic cycle of O-linked GlcNAc (O-GlcNAc) addition and removal is catalyzed by O-GlcNAc transferase and O-GlcNAcase, respectively, in a process that serves as the final step in a nutrient-driven "hexosamine-signaling pathway." Evidence points to a role for O-GlcNAc cycling in diabetes and insulin resistance. We have used Drosophila melanogaster to determine whether O-GlcNAc metabolism plays a role in modulating Drosophila insulin-like peptide (dilp) production and insulin signaling. We employed transgenesis to either overexpress or knock down Drosophila Ogt(sxc) and Oga in insulin-producing cells (IPCs) or fat bodies using the GAL4-UAS system. Knockdown of Ogt decreased Dilp2, Dilp3, and Dilp5 production, with reduced body size and decreased phosphorylation of Akt in vivo. In contrast, knockdown of Oga increased Dilp2, Dilp3, and Dilp5 production, increased body size, and enhanced phosphorylation of Akt in vivo. However, knockdown of either Ogt(sxc) or Oga in the IPCs increased the hemolymph carbohydrate concentration. Furthermore, phosphorylation of Akt stimulated by extraneous insulin in an ex vivo cultured fat body of third instar larvae was diminished in strains subjected to IPC knockdown of Ogt or Oga. Knockdown of O-GlcNAc cycling enzymes in the fat body dramatically reduced neutral lipid stores. These results demonstrate that altered O-GlcNAc cycling in Drosophila IPCs modulates insulin production and influences the insulin responsiveness of peripheral tissues. The observed phenotypes in O-GlcNAc cycling mimic pancreatic β-cell dysfunction and glucose toxicity related to sustained hyperglycemia in mammals.  相似文献   
65.
PFKFB3 is the gene that codes for the inducible isoform of 6-phosphofructo-2-kinase (iPFK2), a key regulatory enzyme of glycolysis. As one of the targets of peroxisome proliferator-activated receptor γ (PPARγ), PFKFB3/iPFK2 is up-regulated by thiazolidinediones. In the present study, using PFKFB3/iPFK2-disrupted mice, the role of PFKFB3/iPFK2 in the anti-diabetic effect of PPARγ activation was determined. In wild-type littermate mice, PPARγ activation (i.e. treatment with rosiglitazone) restored euglycemia and reversed high fat diet-induced insulin resistance and glucose intolerance. In contrast, PPARγ activation did not reduce high fat diet-induced hyperglycemia and failed to reverse insulin resistance and glucose intolerance in PFKFB3+/− mice. The lack of anti-diabetic effect in PFKFB3+/− mice was associated with the inability of PPARγ activation to suppress adipose tissue lipolysis and proinflammatory cytokine production, stimulate visceral fat accumulation, enhance adipose tissue insulin signaling, and appropriately regulate adipokine expression. Similarly, in cultured 3T3-L1 adipocytes, knockdown of PFKFB3/iPFK2 lessened the effect of PPARγ activation on stimulating lipid accumulation. Furthermore, PPARγ activation did not suppress inflammatory signaling in PFKFB3/iPFK2-knockdown adipocytes as it did in control adipocytes. Upon inhibition of excessive fatty acid oxidation in PFKFB3/iPFK2-knockdown adipocytes, PPARγ activation was able to significantly reverse inflammatory signaling and proinflammatory cytokine expression and restore insulin signaling. Together, these data demonstrate that PFKFB3/iPFK2 is critically involved in the anti-diabetic effect of PPARγ activation.  相似文献   
66.
目的 探讨母牛分支杆菌菌苗(简称微卡)治疗糖尿病合并肺结核的疗效。方法 同期选取40例糖尿病合并肺结核初治患者,随机分为A、B组。A组以常规抗痨治疗(2HRZE/4HR),B组在常规抗痨治疗的基础上加用微卡治疗2月。结果 B组结核病灶消散吸收、空洞完全或部分闭合、痰结核菌阴转速度均明显快于A组(P〈0.05),且不良反应少见。结论 微卡可用作糖尿病合并肺结核的免疫治疗。  相似文献   
67.
A validated, simple and sensitive HPLC method was developed for the simultaneous determination of lipoperoxidation relevant reactive aldehydes: glyoxal (GO), acrolein (ACR), malondialdehyde (MDA), and 4-hydroxy-2-nonenal (HNE) in human serum. The studied aldehydes were reacted with 2,2′-furil to form fluorescent difurylimidazole derivatives that were separated on a C18 column using gradient elution and fluorescence detection at excitation and emission wavelengths of 250 and 355 nm, respectively. The method showed good linearity over the concentration ranges of 0.100–5.00, 0.200–10.0, 0.200–40.0, and 0.400–10.0 nmol/mL for GO, ACR, HNE, and MDA, respectively, with detection limits ranging from 0.030 to 0.11 nmol/mL. The percentage RSD of intraday and interday precision did not exceed 5.0 and 6.2%, respectively, and the accuracy (%found) ranged from 95.5 to 103%. The proposed method was applied for monitoring the four aldehydes in sera of healthy, diabetic, and rheumatic human subjects with simple pretreatment steps and without interference from endogenous components. By virtue of its high sensitivity and accuracy, our method enabled detection of differences between analytes concentrations in sera of human subjects under different clinical conditions.  相似文献   
68.
糖尿病(diabetes mellitus,DM)是严重危害人类健康的全身性代谢疾病,常发生血液流变学、微循环和细胞代谢的紊乱,导致缺血、缺氧和组织水肿,进而引起血管和神经病变。血管病变常常是糖尿病病人致死、致残的主要原因。血管平滑肌细胞的增殖及表型改变是糖尿病引发动脉粥样硬化性疾病的显著特征,而线粒体在血管平滑肌细胞的增殖过程中起重要作用。因此,探讨糖尿病血管平滑肌细胞与线粒体的关系及机制为糖尿病血管性疾病的治疗提供重要的理论基础,有利于基础研究向临床试用药物研究的转化。  相似文献   
69.
70.
Pancreatic beta-cells exposed to hyperglycemia produce reactive oxygen species (ROS). Because beta-cells are sensitive to oxidative stress, excessive ROS may cause dysfunction of beta-cells. Here we demonstrate that mitochondrial ROS suppress glucose-induced insulin secretion (GIIS) from beta-cells. Intracellular ROS increased 15min after exposure to high glucose and this effect was blunted by inhibitors of the mitochondrial function. GIIS was also suppressed by H(2)O(2), a chemical substitute for ROS. Interestingly, the first-phase of GIIS could be suppressed by 50 microM H(2)O(2). H(2)O(2) or high glucose suppressed the activity of glyceraldehyde 3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme, and inhibitors of the mitochondrial function abolished the latter effects. Our data suggested that high glucose induced mitochondrial ROS, which suppressed first-phase of GIIS, at least in part, through the suppression of GAPDH activity. We propose that mitochondrial overwork is a potential mechanism causing impaired first-phase of GIIS in the early stages of diabetes mellitus.  相似文献   
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