This study was aimed to compare the efficacy of gastric banding (GB), Roux en-Y gastric bypass (RYGBP) and biliopancreatic diversion (BPD) in the treatment of rats with type 2 diabetes mellitus (T2DM). Ani-mal models of T2DM were induced by streptozotocin (STZ) injection and high-sugar-fat diets. A total of 70 T2DM rats were randomly allocated into the GB group (G group, n = 20), RYGBP group (R group, n = 20), BPD group ( B group , n = 20 ) , and the sham operation group ( S group , n = 10 ) . The fasting blood glucose ( BG ) , triglyceride ( TG ) , total cholesterol ( TC ) and insulin ( INS ) content were determined before and 1 , 2 , 3 , 4 , 8 , 16 weeks after operation. The insulin sensitivity index (ISI) was calculated. The mortality and complications were ob-served in each group. The results showed that the fasting weight of the GB group, RYGBP group and BPD group were (324.4 ± 22.5) g, (338.9 ± 17.5) g, (333.3 ± 28.4) g, respectively. The BG content was (12.44 ± 1.29) mmol/L, (9.70 ± 0.81) mmol/L, (11.93 ± 2.39) mmol/L, respectively. The TC content was (2.32 ± 0.45) mmol/L, (2.22 ± 0.79) mmol/L, (2.13 ± 0.31) mmol/L, respectively. The TG content was (1.38 ± 0.32) mmol/L, (1.16± 0.41) mmol/L, (1.23 ± 0.35) mmol/L, respectively. The ISI were (-6.38 ± 0.29), (-6.67 ± 0.24), (-6.65 ±0.23), respectively. And the INS content of the RYGBP group were (69.43 ± 18.73) mU/L. There were signifi-cant differences between before and after operation on the 16th week ( P < 0 . 05 , P < 0 . 01 ) . The mortality rate was 5% in the GB group, 20% in the RYGBP group, and 35% in the BPD group. It was concluded that the GB, RYGBP and BPD are effective in reducing blood glucose and blood lipids in the treatment of rat with T2DM. The treatment effect is obvious in the improvement of insulin resistance ( IR ) .

Objective To summarize the clinical features,natural history and causes of death of mitochondrial encephalomyopathy,lactic acidosis and stroke-like episodes (MELAS).Methods We retrospectively evaluated the clinical findings of 64 patients diagnosed as MELAS more than 3 years (death cases excluded) in Huashan Hospital from January 2005 to March 2017 and analyzed the natural course and the causes of death of the disease.Results Among 64 patients,the male-to-female ratio was 1.3 ∶ 1.Median onset age was 20.5 (16.8) years.The peak of incidence age was from 14 to 22 years.The most common features of MELAS in acute phase were seizures (48/64,75.0％),headache (41/64,64.1％),blurred vision (37/64,57.8％),nausea and vomiting (27/64,42.1％),fever (25/64,39.1％),mental and behavioral disorder (24/64,37.5％).Lactate dehydrogenase (31/60,51.6％),resting blood lactic acid (43/58,74.1％) and cerebral spinal fluid lactic acid (9/9) were elevated.Abnormal findings in electroencephalogram (36/40,90.0％),electrocardiogram (37/47,78.7％),electromyography (25/41,61.0％) were detected.In this cohort,20 patients (20/64,31.3％) with MELAS were dead.A Kaplan-Meier survival curve showed the estimated overall median survival time was 12 years.The median survival time of the group onset before sex maturity (≤ 14 years) was 8 years and that in the group onset after sex maturity (＞ 14 years) was 21 years.The causes of death were cardiogenic incidence (4/20,20.0％),pulmonary infection (4/20,20.0％),lactic acidosis (2/20,10.0％) and status epilepticus (2/20,10.0％).Conclusions MELAS is usually presented in young people associated with high mortality rate.The leading causes of death are cardiogenic,pulmonary infection and lactic acidosis.