The article introduces the applic at ion of glucose clamp technique in the study of diabetes. The changes in insulin sensitivity, insulin secretion, metabolism of glucose, lipids and protein, etc. in euglycemic or hyperglycemic status in vivo can be investigated by glucose cla mp technique.

The current definition of metabolic syndrome focuses on the individual accumulation of multiple cardiovascular risk factors. However, metabolic syndrome is often also constantly accompanied with abnormal body fat distribution, tissue insulin resistance, low-grade inflammation, and dysfunctional secretion and regulation of adipokines, which have become new highlights in the research of the pathogenesis and clinical indices of metabolic syndrome.
Body Fat Distribution ; C-Reactive Protein ; metabolism ; Humans ; Lipofuscin ; metabolism ; Metabolic Syndrome ; metabolism

Thirty-eight individuals with normal glucose regulation and thirty-nine newly diagnosed type 2 diabetic patients were observed by continuous glucose monitoring system(CGMS)for three days.The mean blood glucose,mean amplitude of glycemic excursions(MAGE),and absolute means of daily differences(MODD)were calculated in each subject.The results suggested that the amplitude of glyeemic excursions revealed by CGMS could be used to evaluate the quality of glycemic control in type 2 diabetic patients.

Objective To establish a method of measuring adipose content and fat distribution of the thigh in normal glucose tolerance (NGT) subjects,and to investigate its relation to insulin resistance.Methods Insulin sensitivity was evaluated by hyperinsulinemic and euglycemic clamp technique,and femoral adipose content and fat distribution were determined by MRI in 30 individuals with NGT including 15 with normal weight and 15 overweighted or obese subjects.Results Compared to normal weight group,the subscutaneous adipose tissue of thigh (SCAT) [(176.7?21.6) cm~2 vs (115.0?12.8 ) cm~2,P＜0.05],adipose tissue of thigh beneath the fascia (SFAT) [(75.4?4.4 ) cm~2 vs (57.5?4.7 ) cm~2,P＜0.01] and intermuscular adipose tissue (IMAT) [(28.3?3.2) cm~2 vs (14.5?1.1 ) cm~2,P＜0.01] were greater in overweight/obesity group.Overweight/ obesity group had lower insulin sensitivity( glucose disposal rate under steady state of hyperinsulinemic euglycemic clamp:4.54?0.43 vs 7.88?0.75,P＜0.01).SFAT and IMAT were significantly correlated with insulin sensitivity.SFAT showed the most marked correlation with insulin sensitivity.Multiple stepwise regression analysis showed that the increased SFAT played a pivotal role in insulin resistance.Conclusion The adipose content and fat distribution are highly correlated with insulin sensitivity and the adipose tissue of thigh beneath fascia may play the most significant role in insulin sensitivity.

OBJECTIVETo study the prevalence and clinical characteristics of the A to G mutation at nucleotide 3243 of the mitochondrial tRNA(Leu(UUR)) gene in familial diabetes in Shanghai, Jiangsu and Zhejiang Province of China.

METHODSThe mt3243 A to G mutation in 770 randomly selected, unrelated probands of diabetic pedigrees were screened by PCR-RFLP technique and PCR-direct sequencing. Genetic and clinical analyses were further performed in the probands and their family members.

RESULTSThirteen diabetic patients (13/770, 1.69%) with mt3243 A to G mutation were detected. Eleven diabetic patients and 8 normal glucose tolerance (NGT) first-degree relatives of these 13 probands were also found bearing the mutation. Seventeen patients were associated with sensory hearing loss. In the 24 patients harboring the mutation, the majority had lower body mass index (BMI), 18 showed typical maternal inheritance, 15 had sensory hearing loss, 13 had insulin resistance and 14 required insulin therapy due to secondary failure to oral hypoglycemic agents.

CONCLUSIONThe mutation of mt3243 A to G in the mitochondrial tRNA(Leu(UUR)) gene is an important cause of diabetes in Shanghai, Jiangsu and Zhejiang Province of China. Mitochondrial gene mutation diabetes (MDM) is clinically characterized by early onset, emaciation, maternal inheritance, sensorineural hearing loss, and lower islet beta cell function, and some have insulin resistance.

Asian Continental Ancestry Group ; genetics ; China ; epidemiology ; DNA, Mitochondrial ; genetics ; Deafness ; genetics ; Diabetes Mellitus ; genetics ; Genetic Testing ; Hearing Loss, Sensorineural ; genetics ; Humans ; Insulin Resistance ; genetics ; Molecular Sequence Data ; Mutation ; Prevalence ; RNA, Transfer, Amino Acyl ; genetics

Objective To analyse the characterisitics of daily blood glucose profiles of insulinoma using continuous glucose monitoring system(CGMS) and to investigate the value of CGMS in the diagnosis of insulinoma. Methods The blood glucose of 6 patients with pathologically-confirmed insulinoma(insulinoma group) were detected by CGMS for 3 consecutive days.The mean blood glucose(MBG),M-value of Schlichtkrull(M-value),frequency distribution of glucose levels and the hypoglycemic episodes of CGMS were measured,and the results were compared with those of normal glucose regulation(n=6,control group) and patients with newly-diagnosed type 2 diabetes with reactive hypoglycemia(n=5,diabetes group). Results The M-value of insulinoma group was significantly higher than that of control group(P0.05).The M-value and MBG of diabetes group were higher than those of insulinoma group and control group(P

0.05),while hyperlactacidemia existed in 21 patients(4.62%).LA levels increased with the creatinine levels,especially in those with Cr more than 90 ?mol/L.However,LA levels increased with the reduction of GFR,especially in those with GFR less than 80 mL/min.It was revealed by correlation analysis that LA level was positively correlated with Cr,ALT and BMI.The optimal cutoff of Cr inducing the lactic acidemia was 95.35 ?mol/L.Conclusion The baseline LA levels of patients with T2DM are similar to those of healthy adults,and LA levels are mainly influenced by BMI and renal and hepatic function.Hyperlactacidemia may be induced when Cr reaches a level more than 95 ?mol/L.

Objective To evaluate the clinical significance of glycated albumin(GA),a parameter in reflection of recent glycemic control in patients with diabetes mellitus. Methods Four hundred and forty-five patients with type 2 diabetes mellitus who were hospitalized in our hospital from May to November 2006 were enrolled into the study.The fasting plasma glucose(FPG),postprandial 2-hour blood glucose(P2hBG) and glycated hemoglobin(HbA1c) were measured,the enzymatic measurement of GA was conducted and the CGMS was performed.The correlation between GA and the other parameters monitored was analysed. Results The correlation analysis indicated that GA was well correlated with HbA1c(r=0.818,P0.05),respectively for those with HbA1c more than 7.5%,between 6.5% and 7.5%,and less than 6.5%. Conclusion GA is well correlated with HbA1c,especially in those with poor glycemic control for a long time.The correlation between GA and long-term glycemic control is stronger than that between GA and instant plasma glucose or MBG in three days.

OBJECTIVETo study the clinical characteristics of hypertensive subjects with metabolic syndrome and its components in communities.

METHODSTotally 5628 subjects aged over 20 years were included. Measurement indicators included height, weight, waist circumference (W) , hip circumference, systolic pressure (SP) , diastolic pressure (DP) , total cholesterol ( TC) , triglyceride (TG) , high-density lipoprotein cholesterol (HDL-C) , low-density lipoprotein cholesterol (LDL-C) , fasting plasma glucose (FPG) , 2 h postprandial plasma glucose (2hPG) , fasting serum insulin (FIN) , and 2 h postprandial serum insulin (2hIN). Body mass index (BMI) , waist to hip ratio (WHR), and homeostatic model approach-insulin resistance index (HOMA-IR) were calculated. According to 1999 WHO definition of metabolic syndrome, these individuals were divided into 4 groups: non-metabolic disorder group, isolated hypertension group, hypertension with one component of metabolic syndrome group, hypertension with two components of metabolic syndrome group, and hypertension with three components of metabolic syndrome group.

RESULTSAmong subjects with hypertension, 15. 37% were patients with isolated hypertension, 32. 40% with one component of metabolic syndrome, 33. 36% with two components of metabolic syndrome, and 18. 87% with three components of metabolic syndrome. BMI, W, WHR, TC, TG, LDL-C, FPG, 2hPG, FIN, 2hIN and HOMA-IR in three groups (hypertension with one component of metabolic syndrome group, hypertension with two components of metabolic syndrome group, and hypertension with three components of metabolic syndrome group) significantly increased than those in isolated hypertension group (P < 0. 01 ). The hypertensive patients showed a higher insulin resistance, despite other metabolic disorders. Furthermore, the hypertensive patients with more components of metabolic syndrome showed a higher chance to get insulin resistance. Multiple stepwise regression analysis showed FPG, 2hPG, FIN, 2hIN, BMI, SP and TC were risk factors of HOMA-IR.

CONCLUSIONSPatients with isolated hypertension are rare in community-based population. About 85% of hypertensive patients have more than one metabolic disorders, more than half of were metabolic syndrome. The percentage of total body fat, levels of plasma glucose, serum insulin, total cholesterol and systolic blood pressure are independent risk factors of insulin resistance.

Adult ; Aged ; Aged, 80 and over ; Blood Glucose ; metabolism ; Body Fat Distribution ; Body Mass Index ; China ; epidemiology ; Female ; Humans ; Hypertension ; complications ; epidemiology ; metabolism ; Insulin ; blood ; Insulin Resistance ; Male ; Metabolic Syndrome ; complications ; epidemiology ; metabolism ; Middle Aged ; Waist-Hip Ratio

Objective To assay serum apelin level in obesity and newly-diagnosed type 2 diabetes mellitus (DM) patients and investigate the relationship between serum apelin level and body fat parameter,glucose and lipid metabolism and insulin resistance index,etc.Methods Sixty-two patients with type 2 DM and 72 subjects with normal glucose regulation (NGR) were selected and each group was divided into obese and non-obese subgroups according to body mass index (BMI)≥25 kg/m~2 or