Byung Doo Rhee

A decision tree-based approach for identifying urban-rural differences in metabolic syndrome risk factors in the adult Korean population

Aim: The purpose of this study was to explore the difference in the pattern of metabolic syndrome (MetS) in urban and rural populations in Korea using data mining techniques. Subjects and methods: In total, 1013 adults >30 yr of age from urban (184 males and 313 females) and rural districts (211 males and 305 females) were recruited from Gyeongsangnam-do, Korea. Modified National Cholesterol Education Program Adult Treatment Panel III criteria were used to identify individuals with MetS. We applied a decision tree analysis to elucidate the differences in the clustering of MetS components between the urban and rural populations. Results: The prevalence of MetS was 33.2% and 35.2% in urban and rural districts, respectively (p=0.598). The decision-tree approach revealed that the combination of high serum triglycerides (TG) + high systolic blood pressure (SBP), high TG + low HDL cholesterol, and high waist circumference (WC) + high SBP + high fasting plasma glucose (FPG) were strong predictors of MetS in the urban population, whereas the combination of TG + SBP + WC and SBP + WC + FPG showed high positive predictive value for the presence of MetS in the rural population. Conclusions: Although no significant difference was found for the prevalence of MetS between the two populations, the differences in the clustering pattern of MetS components in urban and rural districts in Korea were identified by decision tree analysis. Our findings may serve as a basis to design necessary population-based intervention programs for prevention and progression of MetS and its complications in Korea.

Comparison of the efficiency and toxicity of sonoporation with branched polyethylenimine-mediated gene transfection in various cultured cell lines.

Objective. The objective of this study is to evaluate transfection efficiency and safety for gene delivery by sonoporation in comparison with cationic polymer gene carrier branched polyethylenimine (BPEI). Methods. The cDNA expressing VEGF165 was cloned under chicken β-actin promoter. The plasmid DNA was transfected into the CHO, HEK293, and NIH3T3 cells using microbubble-based sonoporation and BPEI (25 kDa) under various conditions. Enzyme-linked immunosorbent assay (ELISA) was used to determine the expressed protein level. Cytotoxicities of transfection methods were compared by Cell Counting Kit-8. Results. At 1 MHz intensity, transfection efficiency of sonoporation was enhanced by microbubble concentration with no detrimental effects. By contrast, BPEI exacerbated cell viability, despite its high transgene expression efficiency. Conclusion. Sonoporation gene therapy might be the safest technique to be used in actual clinical practice.

The effect of chromium on rat insulinoma cells in high glucose conditions

AIMS it has been suggested that Chromium (Cr), one of the essential minerals, can be beneficial to type 2 diabetic patients because it lowers blood glucose levels by improving various steps in insulin action. A few studies reported that Cr might also have some beneficial effects in people with type 1 diabetes mellitus and in streptozotocin-treated rats, but direct beneficial effects of Cr on pancreatic beta cells have not been proven. We performed this study to determine whether Cr could have direct protective effects on INS-1 cells in high glucose conditions that mimic the actual diabetic state. MAIN METHODS INS-1 cells were cultured for 48h in RPMI medium with 33mM glucose as the stress condition and 11mM glucose as a control. CrCl(3) was used to verify whether Cr could protect INS-1 cells from glucotoxic stress. Cell viability and apoptosis were evaluated by MTT assay and FACS. The level of insulin mRNA, by semi-quantitative RT-PCR, was significantly reduced at 33mM glucose concentration after 48h of incubation. KEY FINDINGS cell viability was reduced by 50%, and 35% of the cells underwent apoptosis at the same culture condition. Addition of various concentrations of CrCl(3) to INS-1 cells in 33mM glucose for different durations of time did not reveal any beneficial effects on cell viability, degree of apoptosis, insulin mRNA levels, and glucose stimulated insulin secretion. SIGNIFICANCE we could not find any evidence that Cr had direct beneficial effects on INS-1 cells in high glucose induced stress conditions.

Diabetic Myonecrosis in a Patient with Hepatitis B-Induced Liver Cirrhosis

Diabetic myonecrosis-a rare complication of long-standing, poorly controlled diabetes mellitus-typically presents with acute-onset muscle pain, is self-limiting, and responds well to conservative management. We report a case of diabetic myonecrosis in a 33-year-old man with hepatitis B-induced liver cirrhosis and type 2 diabetes who presented with abdominal distension and pain in the left thigh. Diabetic myonecrosis was diagnosed based on clinical presentation, radiological findings, magnetic resonance imaging and histopathological investigations; he was successfully treated conservatively with insulin and analgesics. Diabetic myonecrosis should be considered in the differential diagnosis of muscle pain in patients with diabetes.