胰腺癌细胞的增殖同膜脂质饱和度,膜胰岛素受体的关系

外源性表皮生长因子(或生长抑素)能促进(或抑制)胰腺癌细胞的增殖。胰腺癌细胞增殖速率的高低与细胞膜脂质饱和度的降、升;与膜胰岛素受体数量的增减密切相关。测定细胞膜脂质饱和度和胰岛素受体数量,是判断胰腺癌增殖状态的灵敏指标,有一定临床价值。     

丙戊酸钠治疗对血清胰岛素、体重指数的影响

目的探讨丙戊酸钠抗癫痫治疗对血清胰岛素、体重指数的影响,血清胰岛素的改变与患者的体重指数的改变的相关性,以及胰岛素抵抗的可能机制。方法以丙戊酸钠治疗超过3个月的25例癫痫患者为治疗组,15例未经丙戊酸钠治疗癫痫患者作为对照组来比较,检测患者体重、身高、血糖、胰岛素水平,比较两组的体重指数(BMI)、稳态模式评估指数(HOMA)和胰岛素水平。结果丙戊酸钠治疗组的HOMA指数(1．6811±0．6492)与对照组(1．1053±0．6129)比较有增高,治疗组BMI(23．634±2．5304)高于对照组(21．8573±2．2458),治疗组血清胰岛素(7．2080±2．5521)MU/L高于对照组(4．5413±1．1767)MU/L。结论丙戊酸钠治疗可能引起血清胰岛素增高并通过诱导导致胰岛素抵抗,从而导致患者体重增加。     

单纯性肥胖及2型糖尿病儿童胰岛素受体底物-1的研究

目的:探讨单纯性肥胖及2型糖尿病儿童胰岛素受体底物-1(IRS-1)表达的改变。方法:对20例单纯性肥胖儿童,20例2型糖尿病儿童及20例对照组儿童,采用细胞免疫技术进行白细胞染色,运用图像分析软件计算光密度值,从而定量分析白细胞中IRS-1的含量变化。结果:肥胖组、2型糖尿病组白细胞中IRS-1表达下降,且与对照组相比有统计学意义(P<0.05)。结论:肥胖组、2型糖尿病组白细胞中IRS-1表达下降,与对照组相比有统计学意义(P<0.05),提示肥胖组与2型糖尿病组儿童胰岛素信号传递中受体后作用的关键底物缺陷,影响了胰岛作用的发挥。提示IRS-1与胰岛素抵抗有关,有利于进一步理解2型糖尿病的发病机制,指导临床治疗。     

Comparison of insulin-binding activity of blood cells in diabetes mellitus in pregnant women

Insulin-binding activity of blood cells in pregnant women is shown to vary considerably in health and in diabetes mellitus with different forms and stages of compensation. More stable changes were observed just in erythrocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 461–464, May, 1994 Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences     

Intra-operative quick insulin assay to confirm complete resection of insulinomas guided by selective arterial calcium injection (SACI)

Background and aims Insulinomas are rare endocrine disorders. Pre-operatively, conventional imaging techniques often fail to localise the tumor. In addition, due to the lack of quick insulin assays, intra-operative confirmation of complete resection was impossible until recently. Materials and methods Six patients with biochemical evidence of an insulinoma underwent pre-operative localisation studies and selective arterial calcium injection (SACI). In addition, insulin was measured before surgery and every 10–15 min after resection of the tumor using a quick insulin assay. Results Pre-operative localisation studies identified the tumor correctly as follows: endosonography: three of four, magnetic resonance imaging: two of four and SACI: six of six. Tumors in the head and body were enucleated while those in the tail were resected (n = 2, each). Those three patients, in whom magnetic resonance imaging and/or endosonography could localise the tumors pre-operatively, underwent laparoscopic surgery while the remaining three patients underwent open surgery. Intra-operatively, insulin dropped to normal levels within 20 min in all cases. After a follow-up of 0.8–3 years, all patients remained biochemically cured. Conclusions Pre-operatively, SACI appears to be a very sensitive localisation technique and may be most helpful in guiding the surgeon if conventional imaging techniques fail to localise the tumor. Complete removal of an insulinoma can be reliably predicted using a quick insulin assay. This paper was presented at the 2nd Biennial Meeting of the European Society of Endocrine Surgeons (ESES), May 18–20, 2006, Krakow, Poland.     

高脂肪膳食对大鼠增食欲素及瘦素系统的影响

目的研究高脂肪膳食诱导的胰岛素抵抗(IR)大鼠下丘脑及脂肪组织中增食欲素和瘦素系统的变化,分析其可能的调控因素。方法IR大鼠模型采用高脂肪膳食诱导并经钳夹技术证实;应用RT-PCR技术检测增食欲素及其受体(OX1R、OX2R)和瘦素受体(LR)以及脂肪组织中瘦素基因mRNA的表达;采用生化比色法测定血清游离脂肪酸(FFA)、放射免疫法测定血清肿瘤坏死因子α(TNF-α)。结果钳夹技术中葡萄糖输注率明显低于对照组;高脂肪膳食诱导的IR大鼠下丘脑中前增食欲素原mRNA的表达较对照组减少约80%(P<0.01);OX1R、OX2R分别增加3.4及3.2倍(P<0.01);瘦素mRNA增加约8倍(P<0.01);LR减少78%;血清FFA和TNF-α均明显高于对照组(P<0.01)。结论高脂肪膳食可诱导大鼠体内IR,并导致增食欲素和瘦素系统平衡状态的破坏;增食欲素和瘦素是机体能量平衡调节网络中的一对重要物质,两者相互作用共同维持机体能量代谢的稳定。血清FFA和TNF-α均可能参与该系统的调控,合理膳食在这一调控中至关重要。     

褪黑素对胰岛素抵抗大鼠肾皮质内皮素、内皮型一氧化氮合酶平衡的影响

目的 研究褪黑素对胰岛素抵抗(IR)大鼠肾皮质内皮素1(ET-1)、内皮型一氧化氮合酶(eNOS)表达的影响.方法 高糖饲料喂养SD大鼠6周复制IR大鼠模型.成模后用药组(MEL组)予褪黑素10mg·kg-1·d-1灌胃,用药6周.未用药IR大鼠模型为对照(IR组).免疫组化、RT-PCR方法 检测肾皮质ET-1、eNOS蛋白和mRNA表达的改变.结果 与IR组相比,褪黑素组大鼠动脉血压(ABP)、血清TG、游离脂肪酸(FFA)、丙二醛(MDA)、胰岛素(Ins)和HOMA-IR降低(P＜0.01),血清HDL-c、超氧化物歧化酶(SOD)升高(P＜0.01).HE染色MEL组大鼠肾皮质病变明显减轻.MEL组ET-1蛋白及mRNA明显低于IR组、eNOS蛋白及mRNA明显高于IR组,差别均有显著意义(P＜0.05).结论 在IR早期应用褪黑素(10mg·kg-1·d-1)治疗可以减轻IR大鼠肾皮质ET-1与eNOS平衡的异常,对肾皮质血管内皮功能具有一定保护作用.     

体外胰岛素样生长因子结合蛋白-1对人血管内皮细胞生长的抑制作用

目的 观察胰岛素样生长因子结合蛋白-1对人血管内皮细胞的影响及其对胰岛素样生长因子的调节作用。方法 MTT比色法观察IGFBP-1及与IGF-1预混后对脐静脉内皮细胞(ECV304细胞株)生长影响。结果 IGFBP-1对内皮细胞ECV304的生长具有抑制作用且与剂量成正比；预混后各组IGF-1促细胞生长作用明显被抑制。结论 IGFBP-1既可以直接也可以通过调节IGF-1抑制血管内皮细胞生长。     

Nocturnal hypoglycaemia in Type 1 diabetic patients,assessed with continuous glucose monitoring: frequency,duration and associations

Aims We quantified the occurrence and duration of nocturnal hypoglycaemia in individuals with Type 1 diabetes treated with continuous subcutaneous insulin infusion (CSII) or multiple‐injection therapy (MIT) using a continuous subcutaneous glucose sensor. Methods A microdialysis sensor was worn at home by 24 patients on CSII (mean HbA_1c 7.8 ± 0.9%) and 33 patients on MIT (HbA_1c 8.7 ± 1.3%) for 48 h. Occurrence and duration of nocturnal hypoglycaemia were assessed and using multivariate regression analysis, the association between HbA_1c, diabetes duration, treatment type (CSII vs. MIT), fasting and bedtime blood glucose values, total daily insulin dose and mean nocturnal glucose concentrations, and hypoglycaemia occurrence and duration was investigated. Results Nocturnal hypoglycaemia ≤ 3.9 mmol/l occurred in 33.3% of both the CSII‐ (8/24) and MIT‐treated patients (11/33). Mean (± sd ; median, interquartile range) duration of hypoglycaemia ≤ 3.9 mmol/l was 78 (± 76; 57, 23–120) min per night for the CSII‐ and 98 (± 80; 81, 32–158) min per night for the MIT‐treated group. Multivariate regression analysis showed that bedtime glucose value had the strongest association with the occurrence (P = 0.026) and duration (P = 0.032) of nocturnal hypoglycaemia. Conclusions Microdialysis continuous glucose monitoring has enabled more precise quantification of nocturnal hypoglycaemia occurrence and duration in Type 1 diabetic patients. Occurrence and duration of nocturnal hypoglycaemia were mainly associated with bedtime glucose value.