维生素D与多囊卵巢患者胰岛素抵抗相关性及其机制研究

目的:探讨维生素D对多囊卵巢综合征(PCOS)患者胰岛素抵抗(IR)的影响及其机制研究.方法:选取自2013年2月～2014年2月在该院就诊的48例PCOS患者作为PCOS组,另选30例健康育龄期妇女作为对照组,测量研究者身高、体质量参数,计算体质指数(BMI),采用全自动生化分析仪葡萄糖氧化酶检测空腹血糖浓度(FBG)、化学发光法检测血清空腹胰岛素(FI)及胰岛素样生长因子-1(IGF-1)水平、ELISA方法测定血清25-(OH)D3浓度,计算稳态胰岛素评价指数(HOMA-IR)用于评价胰岛素抵抗性,量化胰岛素敏感指数(QUICKI)用于评价胰岛素敏感度,并分析FI、HOMA-IR、QUICKI及IGF-1与血清25-(OH)D3浓度的相关性.结果:PCOS组BMI及FBG与对照组相比,差异无统计学差异(P＞0.05),而FI、HOMA-IR、QUICKI、25-(OH) D3及IGF-1与对照组比较,差异均有统计学差异(P＜0.05);并且PCOS组FI和HOMA-IR与血清25-(OH)D3浓度呈显著负相关,差异有统计学意义(P＜0.05),QUICKI和IGF-1水平与血清25-(OH)D3浓度呈显著正相关,差异有统计学意义(P＜0.05).结论:PCOS患者IR可能与血清中维生素D缺乏有关,而IGF-1分泌减少又可能是导致PCOS患者维生素D缺乏的重要原因.     

Non alcoholic fatty liver disease and risk of incident diabetes in subjects who are not obese

Background and aims

It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese.

改善胰岛素敏感性对血压影响的相关研究

目的 :观察胰岛素增敏剂二甲双胍改善 2型糖尿病胰岛素敏感性后对血压的影响。方法 :71例 2型糖尿病人口服二甲双胍 (格华止 ) 85 0 mg,qd-bid。治疗前后测定 BMI、血压、FBG、PBG、FINS、PINS,并按 HOMA模型计算胰岛素抵抗指数和胰岛素分泌指数。结果 :( 1)二甲双胍治疗 8周后 ,BMI治疗前后无显著性差异 ;血压治疗后明显下降 ,降压幅度达 ( 13.1± 4.97) /( 4 .2 2± 9.93) mm Hg,血压治疗前后有显著性差异。 ( 2 )治疗后 F BG、 PBG、 FINS均明显下降 ,治疗前后有显著性差异。 ( 3)治疗后 HOMA-IR下降 ,IAI升高 ,治疗前后有显著性差异 ,但 HOMA-IS、 FINS/FBG无显著性差异。结论 :二甲双胍治疗 2型糖尿病 ,在降低血糖、改善 IR的同时 ,伴有血压的明显下降     

早期胰岛素强化序贯治疗在ICU中的临床应用

本文通过复习相关文献资料，就早期胰岛素强化序贯治疗在ICU病人治疗中应用的几个主要方面进行扼要的综述，以利临床医生的参考。     

Uncooked rice of relatively low gelatinization degree resulted in lower metabolic glucose and insulin responses compared with cooked rice in female college students

Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses.     

二甲双胍在多囊卵巢综合征的作用

生殖及代谢异常是多囊卵巢综合征(PCOS)的特征性表现。已证实高胰岛素血症及胰岛素抵抗,导致血中雄激素水平过高,是PCOS的重要发病机制。二甲双胍(metformin)称为胰岛素增敏剂,用于治疗PCOS后,可减轻高雄激素血症,使月经周期规律,改善卵巢对诱导排卵的反应,提高妊娠率,降低早孕流产率,且能减低发展为II型糖尿病及心血管疾病的危险性。本文就国外近年有关metformin运用于PCOS的进展作一综述。     

Ex Vivo Evaluation in Normal Dogs of Insulin Released by a Bioartificial Pancreas Containing Isolated Rat Islets of Langerhans

In bioartificial pancreatic systems, isolated islets of Langerhans are protected against immune rejection by an artificial membrane, permeable to glucose and insulin, but not to immunoglobulins and lymphocytes. Some of these devices, referred to as vascular systems, are set up to be connected to a vascular site in the recipient, with blood circulating in contact with one side of the membrane, and the islets on the other side. Such a bioartificial pancreas, containing isolated rat islets of Langerhans, was connected to an arteriovenous shunt of a normal anesthetized dog. The aim of this experiment was to investigate the kinetics of the insulin secretory response of the system to a glucose load. Glucose was infused upstream of the system, increasing the glucose concentration inside the bioartificial pancreas from 7 to 14 mmol/l, without altering the blood glucose concentration of the dog. Insulin concentration was determined simultaneously upstream and downstream of the bioartificial pancreas. Insulin production was calculated by multiplying the difference between these values by the blood flow rate. Blood flow rate (Q) was estimated from the change in the glucose concentration produced by the glucose infusion using a mass transfer analysis derived from Fick's principle. Insulin production increased from 20 +/- 8 to 59 +/- 15 microU/100 islets/min within 15 min following the beginning of the stimulation (n = 6, p less than 0.05). Five min after the end of the stimulation, insulin production decreased from 75 +/- 13 to 50 +/- 9 microU/100 islets/min (p less than 0.05) to reach the basal level (21 +/- 3 microU/100 islets/min) 30 min after the end of the glucose stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)     

糖尿病腹膜透析患者胰岛素治疗方案探讨

目的探讨糖尿病腹膜透析(CAPD)患者合理的胰岛素应用方法.方法采用横断面研究方法调查所有接受CAPD治疗至少6个月以上的糖尿病肾病患者的胰岛素使用方案及血糖控制情况.并在横断面研究的基础上,动态观察24例新收的糖尿病CAPD患者透析前、后胰岛素的使用方法、剂量调整方案及血糖控制情况.结果2002年6月至2002年12月间共25例2型糖尿病CAPD患者,其中腹腔内注射胰岛素(IP)6人,皮下注射胰岛素(SC)9人,腹腔和皮下联合应用(IP SC)7人.①空腹血糖、糖化血红蛋白、透析液糖总负荷量、透析液平均糖浓度、透析剂量在IP、SC、IP SC三组间差异均无显著性,(P＞0.05);②与IP及IP SC组相比,SC组胰岛素用量明显减少,(P＜0.05);③腹膜炎的总发生率为1次/每15患者月,明显高于同期非糖尿病腹膜透析患者的腹膜炎发生率(1次/每48患者月),(P＜0.01);④动态观察24例新收的糖尿病CAPD患者,胰岛素剂量较透析前平均增加了(0.33±0.23)倍.透析后调整的胰岛素实际增加量与理论预测增加量差异无显著性,(P＞0.05).患者血糖控制良好,平均为(5.81±1.22)mmol/L.结论皮下注射胰岛素是有效控制糖尿病CAPD患者血糖水平的适当途径.腹膜透析后,可在原有皮下应用胰岛素方案的基础上,参照糖吸收量计算需增加的胰岛素用量适当增减胰岛素,能有效控制血糖.     

Gating modifier peptides as probes of pancreatic beta-cell physiology.

Pancreatic beta-cells depolarize in response to glucose and fire calcium-dependent actions potentials that trigger insulin secretion. The major current responsible for action potential repolarization in these cells is a delayed rectifier and Kv2.1 subunits are thought be a major contributor of the delayed rectifier channels. Hence, blockers of Kv2.1 channels might prolong action potentials and enhance calcium influx and insulin secretion. However, the lack of specific small molecule Kv2.1 inhibitors has hindered the testing of this mechanism. Importantly, several gating modifier peptides inhibit Kv2.1 channels in a relatively specific fashion. Hanatoxin (HaTX) and guangxitoxin-1 (GxTX-1) are examples that have been used to probe the role of Kv2.1 channels in beta-cell physiology. Both HaTX and GxTX-1 strongly inhibit the Kv current of beta-cells from various species, arguing that Kv2.1 subunits contribute significantly to the beta-cell delayed rectifier. GxTX-1 prolongs glucose-triggered action potentials, enhances glucose-dependent intracellular calcium elevations and augments glucose-dependent insulin secretion. Taken together, these data suggest that blockers of Kv2.1 channels may be a useful approach to the design of novel therapeutic agents for the treatment of type 2 diabetes. These studies highlight the utility of gating modifier peptides in the study of physiological systems.     

Inhibitory effect of fluoride on the secretion of insulin

Summary The oral administration of sodium fluoride (NaF) (40 μmol/100 body weight [bw]) to fasting rats produced an immediate fall in insulin levels and the consequent increase in glycemia. These phenomena were observed with plasma fluoride concentrations 5–15 μM. Glycemia and insulin returned to normal levels within 4–5 hours, together with the washing out of fluoride from plasma and soft tissues. The insulin secretion of isolated Langerhans islets, perifused with solutions containing 5, 10, or 20 μM fluoride, was found to be significantly inhibited as a function of fluoride levels, both with basal and stimulatory concentrations of glucose. One hour after the intake of 60 mg of NaF, fasting human volunteers showed increased fluoride (5–15 μM) together with a significant fall of plasma insulin levels.