天麻成分对羟基苯甲醛抗血小板聚集作用及急性毒性研究

为探讨天麻成分对羟基苯甲醛的抗血小板聚集作用,本实验以二磷酸腺苷(ADP)、花生四烯酸(AA)、血小板活化因子(PAF)为诱导剂,探讨了对羟基苯甲醛的体外抗血小板聚集活性;采用ADP静脉注射致小鼠肺栓塞方法以及下腔静脉结扎致大鼠静脉血栓方法,考察了对羟基苯甲醛的体内抗血小板聚集活性;并对经口给药的对羟基苯甲醛的急性毒性进行了检测。结果表明,天麻成分对羟基苯甲醛对ADP诱导的家兔体外血小板聚集有明显的对抗作用,其半数抑制率(50%inhibitory concentration,IC50)为2mmol/L,对PAF诱导的家兔体外血小板聚集无明显影响;天麻成分对羟基苯甲醛能明显降低小鼠肺栓塞死亡率,并显著对抗大鼠下腔静脉血栓的形成。说明天麻成分对羟基苯甲醛在体外、体内均具有显著的抗血小板聚集活性。急性毒性研究结果表明天麻成分对羟基苯甲醛经口给药的小鼠半数致死量(lethal dose 50,LD50)为1.23 g/kg。

对羟基苯甲醛可预防大鼠急性脑缺血后神经炎症

目的探讨对羟基苯甲醛(天麻乙酸乙酯提取物中有效成分)减轻大鼠急性脑缺血损伤后神经炎症的作用并探讨其作用机制。方法采用大鼠颈内动脉注射花生四烯酸诱发多发性脑血栓模型,造模后3 h后处死动物,检测脑内前炎症因子肿瘤坏死因子-α(TNF-α)和白介素-1β(IL-1β)为指标,评价对羟基苯甲醛的脑组织的保护作用;采用脂多糖(LPS)刺激BV-2小胶质细胞复制神经炎症模型,探讨对羟基苯甲醛的抗炎作用机制。结果对羟基苯甲醛能显著降低脑内前炎症因子TNF-α和IL-1β的含有量,降低LPS刺激BV-2小胶质细胞炎症模型细胞上清液中炎症介质NO、前列腺素E2(prostaglandin E2,PGE2)和炎症因子TNF-α的水平,提高正常BV-2小胶质细胞中白介素-10(interleukin-10,IL-10)和转化生长因子-β(transforming growth factors-β,TGF-β)的水平。结论天麻中的对羟基苯甲醛可减轻脑缺血后小胶质细胞过度激活和促进小胶质细胞向抗炎表型转化。

糖化血红蛋白在妊娠期糖尿病孕妇中的检测价值

目的：研究糖化血红蛋白在妊娠期糖尿病（ GDM）孕妇中的检测价值。方法选取2013年8月至2014年8月在南方医科大学第五附属医院产检或待产的120例孕妇作为研究对象,按照纳入标准进入GDM组60例,采用随机数字表法随机选取正常孕妇60例为对照组,分别检测糖化血红蛋白（HbA1c）、空腹血糖并进行50g葡萄糖筛查试验（GCT）和口服75g葡萄糖耐量试验（OGTT）。使用受试者工作特征（ROC）曲线将 GCT和 HbA1c水平作为 GDM 的筛查指标进行统计学分析。结果GDM组HbA1c和GCT水平均高于正常孕妇组,两组间HbA1c差异有统计学意义（t=19.052,P〈0.001）；两组间GCT差异亦有统计学意义（t=22.631,P〈0.001）。 ROC曲线分析GCT取7.9mmol/L,灵敏度为65.1%～69.2%,特异度61.9%～63.5%；HbA1c取5.8%,灵敏度为85.2%～87.6%,特异度79.4%～80.3%。结论在GDM诊断中,HbA1c敏感性较GCT强,故更适合对GDM筛查。

Glycemic variability in insulin treated type 2 diabetes with well-controlled hemoglobin Alc and its response to further treatment with acarbose

Background Glycemic variability, an HbAlc-independent risk factor, has more deleterious effects than sustained hyperglycemia in the development of diabetic complications. This study analyzed the characteristics of glycemic variability in type 2 diabetes mellitus （T2DM） with HbAlc 〈6.5% in duration of twice daily premixed insulin treatment and the effect of further treatment with acarbose. Methods Eighty-six T2DM patients who used premixed insulin analogue （insulin aspart 30） twice daily and had HbAlc 〈6.5% and 20 controlled subjects with normal glucose regulation （NGR） were monitored using the continuous glucose monitoring （CGM） system. The mean amplitude of glycemic excursions （MAGE）, mean of daily differences （MODD） were used for assessing intra-day, inter-day glycemic variability. Hypoglycemia was defined as glucose level 〈3.9 mmol/L for at least 15 minutes in CGM. According to reference values of MAGE, T2DM patients were classified into two groups： Iow-MAGE group with MAGE 〈3.4 mmol/L （L-MAGE） and high-MAGE group with MAGE 〉3.4 mmol/L （H-MAGE）. H-MAGE group received further treatment with acarbose for 2 weeks and was monitored a second time with CGM system. Results After first CGM, L-MAGE group had 41 cases, and H-MAGE group had 45 cases. The MAGE and MODD of T2DM group were all higher than those of subjects with NGR （P 〈0.01）. Twenty-four percent （n=11） in H-MAGE group had a total of 13 hypoglycemic events, 10 of the 13 events occurred at night, meanwhile 5% （n=-2） in L-MAGE group had a total of 2 hypoglycemic events, which also occurred at night （hypoglycemic events： 24% vs. 5%, X2=6.40, P 〈0.01）. MAGE value was correlated with hypoglycemia value and 2-hour postprandial plasma glucose value （r=-0.32 and 0.26, respectively, P 〈0.05）. After further acarbose therapy and secondly CGM, MAGE and MODD values in H-MAGE group were all significantly decreased （40%, P 〈0.01, and 15%, P 〈0.05, respectively）, but remained higher than in the subjects with NGR （P 〈0.05）; 2% （n=-l） had a total of 1 hypoglycemic event, incidence significantly decreased （2% vs. 24%, X2=9.61, P 〈0.01）. Conclusions CGM system can detect the glycemic variability and asymptomatic hypoglycemic events of T2DM with well-controlled HbAlc in duration of insulin treatment. Combination therapy of premixed insulin twice daily with acarbose can flat glycemic variability and decrease hypoglycemic events.

2型糖尿病及糖耐量减低3种筛查方法的效果比较

目的比较FBG、糖尿病危险积分(DRS)表、HbA1c筛查T2DM及IGT的效果。方法选取研究对象458名,采集FBG、填写DRS表,1周后行OGTT并测定HbA1c及血脂4项。结果当筛查T2DM时,FBG切点为5.6mmol/L,DRS切点为9分,HbA1c切点为5.8%。HbA1c筛查效果较好,敏感性为74.36%,特异性为81.55%。当筛查T2DM及IGT时,FBG切点为5.8mmol/L,DRS切点为9分,HbA1c切点为5.9%。DRS筛查效果较好,敏感性为70.31%,特异性为79.37%。结论与FBG和DRS相比,HbA1c筛查T2DM的效果较好,HbA1c及FBG不适用于普查T2DM及IGT,而DRS用于普查T2DM及IGT的效果较好。