Aims. - Recent epidemiological studies have suggested an association between sarcopenia and nonalcoholic fatty liver disease (NAFLD) in the general population, prompting our investigation into the gender-specific association between sarcopenia and NAFLD in patients with type 2 diabetes mellitus (T2DM). Methods. - In this cross-sectional study, 4210 patients with T2DM were recruited from the Seoul Metabolic Syndrome Cohort. Appendicular skeletal muscle mass (ASM) was estimated from bioimpedance analysis measurements, and the skeletal muscle mass index (SMI) was calculated by dividing the sum of ASM by body weight. Sarcopenia was defined as a gender-specific SMI value > 2 standard deviations (SDs) below the mean for healthy young adults. NAFLD was defined as the presence of hepatic steatosis on ultrasonography with no other causes of chronic liver disease. Results. - Among the entire study population (mean age: 57.4 +/- 10.8 years), 1278 (30.4%) had NAFLD and 1240 (29.5%) had sarcopenia, and the prevalence of NAFLD was significantly higher in those with sarcopenia: 46.2% vs 25.1% (P < 0.001) in men; 38.3% vs 25.4% (P < 0.001) in women. Sarcopenia was significantly associated with higher risk of NAFLD in men (adjusted odds ratio [OR]: 1.58, 95% confidence interval [CI]: 1.15-2.17), whereas the association was attenuated in women after adjusting for clinical risk factors. Conclusion. - Sarcopenia is independently associated with NAFLD in men with T2DM, which suggests that sarcopenia may be a risk factor for NAFLD in men with T2DM. (C) 2019 Elsevier Masson SAS. All rights reserved.

The study proposes a Co-axial multi-tube heat exchanger (CMTHE) applicable to geothermal heat extraction. The heat exchanger is integrated with a 50 kW geothermal ORC power plant having a working fluid of R-245fa. Two field tests were performed to examine the system response of the ORC system subject to change of CMTHE. In case 1 where the flow rate in the shell-side of CMTHE is maintained, the pressure variation in the shell-side of CMTHE casts minor variations on heat extraction, ORC power generation, and ORC efficiency during the transient. Moreover, the effect of pressure has barely any influence of the final states of heat extraction, ORC power generation, and ORC efficiency. In case 2 where the pressure is preserved in the CMTHE, it is found that a decrease of flow rate in the CMTHE results in degradation of heat extraction, ORC power generation and ORC system efficiency. On the contrary, increasing the flow rate in the CMTHE leads to a rise of heat extraction, ORC power generation and ORC system efficiency. Unlike that in case 1, the effect of flow rate has a detectable effect on the final states of heat extraction, ORC power generation, and ORC efficiency.

Although the HLA class II alleles and immunological abnormalities are associated with type 1 diabetes mellitus (T1DM) in all racial groups, there are considerable variations in the genotypes and the prevalence of autoantibodies. In order to investigate the characteristics of the immunogenetic patterns and to use these as an early diagnostic tool and guideline for a therapeutic plan, we examined the clinical characteristics and the patterns of anti-GAD antibody (GADA), IA-2 antibody (IA-2A), HLA-DR and HLA-DQ in Korean adult-onset T1DM patients. Adult-onset patients had higher serum C-peptide levels than child-onset patients. In adult-onset patients, the prevalence of GADA and IA-2A were 59.5% and 15.3% respectively, and increased frequencies of HLADR4 and-DR9 were found. The frequencies of HLADQA1,-DQB1 and-DQ heterodimers were similar to those of the control, but child-onset patients had high frequencies of the HLA-DR3,-DR4,-DR9, DQA1*0301, DQA1*0501 and DQB1*0201 genotypes. In conclusion, Korean adult-onset T1DM patients had a lower prevalence of GADA, which was comparable to that found in Caucasian patients. The detection of GADA might help to predict the insulin dependency of adult-onset diabetes. Difference in the frequencies of diabetes associated with HLA type suggests that there might be a heterogeneity in the pathogenesis of diabetes according to the age of onset.

SummaryObjective Low birthweight is associated with insulin resistance later in life, and adiponectin is known to play an important role in insulin resistance. We have investigated whether birthweight has a relationship with adiponectin levels in adolescence.Patients An at‐home questionnaire survey was completed by 660 middle‐school students (aged 12–15 years) in Seoul, Korea, and 152 participants were selected randomly based on their birthweight.Measurements Subjects were separated into three groups according to birthweight. We recorded the birthweight and measured anthropometric factors including blood pressure, lipid profile, homeostasis model assessment of insulin resistance (HOMA‐IR) and β‐cell function (HOMA‐β), and adiponectin levels of the subjects. These parameters were compared among the groups. The relationship between birthweight and physiological characteristics in adolescence was examined.Results Systolic blood pressure, lipid profiles and fasting plasma glucose were not significantly different among the groups, but diastolic blood pressure was lower in the third tertile. Insulin, C‐peptide and HOMA‐IR were higher in the low birthweight tertile. After adjustment for confounding factors, birthweight was inversely related to diastolic blood pressure, insulin, C‐peptide and HOMA‐IR. Adiponectin level had a significant relationship with current body mass index (BMI) (r = –0·291; P < 0·001) but not with birthweight (r = 0·117; P = 0·166).Conclusions Although birthweight is closely related to insulin resistance during adolescence, adiponectin levels during adolescence had no significant relationship with birthweight. This result implies that low birthweight may not permanently affect adiponectin levels, but current body size is more closely associated with a decreased adiponectin level. However, the limited importance of birthweight as a determining factor on the adiponectin level later in life needs to be further evaluated.

Low birth weight is associated with insulin resistance and type 2 diabetes in adults. The fetal programming hypothesis has shown that insulin resistance and its associated metabolic disturbances result from a poor gestational environment, for which low birth weight is a surrogate. An at-home questionnaire survey was performed on 660 middle school students (12-15 years) in Seoul, Korea, and 152 cases were randomly selected based on their birth weight. Subjects were divided into three groups according to birth weight. We recorded their birth weight and measured their current anthropometric data, blood pressure, lipid profile, HOMA-IR, and HOMA-beta, and compared these parameters among the groups. The relation of birth weight to physiological characteristics in adolescence was examined. Systolic blood pressure, lipid profiles, and fasting plasma glucose, HOMA-beta were not significantly different among the groups, but diastolic blood pressure was lower in the third tertile. Insulin, C-peptide, and HOMA-IR were higher in the lower birth weight tertile. After adjustment for confounding factors, birth weight was inversely related to diastolic blood pressure, insulin, C-peptide, and HOMA-IR. We conclude that low birth weight may predict the risk of the insulin resistance and its progression over age, and that adequate gestational nutrition is therefore necessary to prevent low birth weight.

The aims of this study were to compare the prevalence of the metabolic syndrome according to the WHO and NCEP ATP III criteria in Korean adults, and to compare the prevalence of the metabolic syndrome with the results in previous Korean studies. The study comprised 1,230 subjects (627 men, 603 women) aged 30-79 years (mean 52.4 +/- 10.3 years) who underwent medical check-up from April to June, 2001 in the Korea Association of Health (KAH). The prevalence of the metabolic syndrome according to the modified WHO criteria was 21.8% of men and 19.4% of women. However, the prevalence was increased 1.6 times (34.2%) in men and 2.0 times (38.7%) in women using the modified NCEP criteria. The prevalence of the metabolic syndrome has varied widely according to differences in the criteria. Thus, further studies are necessary to define the appropriate criteria of the metabolic syndrome for Korean adults.

This study evaluated the efficacy of rosiglitazone in non-obese and obese Korean type 2 diabetic patients of long duration. A total of 125 patients (M:F = 44:81, mean age: 58.4 ± 9.1 years, BMI: 24.2 ± 2.7kg/m2, duration of diabetes: 11.0 ± 6.4 years) were randomly allocated to 12 weeks of rosiglitazone treatment (4mg per day) or a control group. Responders were defined as patients who experienced fasting plasma glucose (FPG) reduction of >20% or HbA1c reduction of >1 (%). Rosiglitazone significantly improved glycemic control by reducing FPG and HbA1c (−3.4mmol/l and −1.1%, P < 0.001, respectively). It also significantly increased HOMAβ-cell function (+9.7, P < 0.01) and QUICKI (+0.029, P < 0.001), and decreased HOMAIR (−1.73, P < 0.001). Females and those with higher waist–hip ratio made up a greater portion of rosiglitazone-responders. Responders (45 patients, 75%) also showed significantly higher FPG, HbA1c, systolic blood pressures, fasting insulin levels and HOMAIR, and lower QUICKI than nonresponders. Among these parameters of responders, waist–hip ratio of non-obese subgroup, initial glycemic control of obese subgroup, and systolic blood pressure of both subgroups lost their significance after subdivision analysis. However, the baseline HOMAIR and QUICKI were significantly correlated with the response rate to rosiglitazone. Moreover, in multiple logistic regression analysis, HOMAIR and QUICKI retained their significance as the independent predictors. Even in Korean type 2 diabetic patients of long duration but with relatively preserved β-cell function, rosiglitazone improved glycemic control, insulin sensitivity, and β-cell function. In this ethnic group, female gender, central obesity, and especially severe insulin resistance were identified as predictive clinical parameters of rosiglitazone-responders.

BACKGROUND:Obesity and type 2 diabetes are well-known risk factors for the development of nonalcoholic fatty liver disease (NAFLD). However, NAFLD is not rare in nonobese, nondiabetic adults. The aim of this study was to evaluate the metabolic significance of NAFLD in nonobese, nondiabetic adults. METHODS:This study examined 768 nonobese (body mass index [BMI] [calculated as weight in kilograms divided by the square of height in meters], > or =18.5 and <30) (460 normal-weight and 308 overweight subjects), nondiabetic individuals older than 30 years who participated in a medical checkup. All the subjects had negative serologic findings for hepatitis B and C viruses and had an alcohol intake less than 140 g/wk. A standard interview, anthropometrics, a biochemical study, and abdominal ultrasonography were conducted. RESULTS:The prevalence of NAFLD in the enrolled subjects was 23.4%. In the normal-weight (BMI, > or =18.5 and <25) and overweight (BMI, > or =25 and <30) groups, NAFLD was a significant predictor of insulin resistance and other metabolic disorders, including hypertriglyceridemia and hyperuricemia. The odds ratio of the metabolic disorders in subjects with NAFLD compared with those without NAFLD in the normal-weight group was higher than that in the overweight group. Multiple logistic regression analysis showed that sex, waist circumference, triglyceride level, and insulin resistance were independently associated with NAFLD in the normal-weight group. CONCLUSIONS:Nonalcoholic fatty liver disease is closely associated with metabolic disorders, even in nonobese, nondiabetic subjects. Nonalcoholic fatty liver disease can be considered an early predictor of metabolic disorders, particularly in the normal-weight population.

Aims First-degree relatives of patients with Type 2 diabetes mellitus (T2DM) are often reported to be insulin resistant. We wanted to identify early metabolic abnormalities in this condition, and determine whether they are altered by regular physical training.Methods We measured insulin sensitivity using the euglycaemic glucose clamp technique and insulin response to oral glucose in 10 unfit (did not participate in routine physical exercise) offspring of T2DM parents and 10 unfit control subjects, and compared them with six fit (routinely swam for 3 h/day 5 days/week) offspring of T2DM parents and six fit controls with no family history of T2DM.Results Unfit offspring had a higher plasma glucose response than the other three groups. The mean area under the glucose curve was also significantly higher in unfit offspring than in the other three groups (12.6 +/- 0.6 vs. 10.4 +/- 0.4, 9.6 +/- 0.5, and 9.5 +/- 0.7 mmol/l per hour for the unfit controls, fit offspring and fit controls, respectively; P < 0.05). The corresponding insulin response of unfit offspring was significantly higher at 60 min in the oral glucose tolerance test (OGTT) that that of fit offspring or fit controls. In addition, the mean area under the insulin curve was significantly greater in unfit offspring than in either fit offspring or fit controls (868 +/- 172 vs. 294 +/- 71, 287 +/- 43 mmol/l per hour, respectively; P < 0.05). Moreover, the glucose disposal rate (GDR), measured using a euglycaemic clamp, was significantly lower in unfit and fit offspring than in unfit and fit controls (5.6 +/- 0.3 vs. 8.6 +/- 0.3 mg/kg per minute; P < 0.01 and 9.3 +/- 0.9 vs. 12.1 +/- 0.8 mg/kg per minute, respectively; P < 0.015), whereas the GDR was similar in unfit controls and fit offspring (8.6 +/- 0.4 vs. 9.3 +/- 0.9 mg/kg per minute; P > 0.05).Conclusion These results support the concept that early metabolic abnormalities, as reflected by a decreased GDR (insulin sensitivity) in the offspring of T2DM patients, may be improved by increased physical fitness.