Diabetic Ketoacidosis Following Colonoscopy in Fulminant Type 1 Diabetes: A Case Report / 대한내과학회지

Fulminant type 1 diabetes is a distinct subtype of type 1 diabetes mellitus that is characterized by sudden, complete destruction of pancreatic beta cells at the disease onset. Since the disease was first described in 2000 in Japan, a number of case reports have also been published in Korea. However, this disease entity is still not well defined. A 48-year old man with no medical history was admitted with diabetic ketoacidosis. Fulminant type 1 diabetes was diagnosed and he was discharged with multiple insulin injections. His serum glucose level was well controlled in the outpatient clinic. A month later, diabetic ketoacidosis occurred again following a diagnostic colonoscopy. This case suggests that fulminant type 1 diabetes is an aggressive disease in which small stimuli can provoke ketoacidosis. Therefore, for tests that require fasting, close observation by medical staff and patient education about the disease is essential.

Effect of Dapagliflozin on Alanine Aminotransferase Improvement in Type 2 Diabetes Mellitus with Non-alcoholic Fatty Liver Disease

BACKGROUND: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are expected to improve the liver function of patients with non-alcoholic fatty liver disease (NAFLD) combined type 2 diabetes mellitus (T2DM) by its characteristic mechanism. This study was designed to investigate the effect of dapagliflozin, one of the SGLT2i, on the liver function of T2DM with NAFLD when combined with metformin. METHODS: Among patients who received dual oral hypoglycemic agents within the 3 months of diagnosing NAFLD, patients who had abnormal alanine aminotransferase (ALT) level (>40 IU/L) were included. Patients were divided into two groups: metformin+dapagliflozin group and metformin+dipeptidyl peptidase-4 inhibitors (DPP4i) group. Demographic data, biochemical data and the clinical and treatment histories of all patients were reviewed. RESULTS: A total of 102 patients were included (dapagliflozin group, n=50; DPP4i group, n=52). Dapagliflozin group showed more weight loss and more ALT decline than DPP4i group (−2.9 kg vs. −0.4 kg, P=0.005; −21.1 U/L vs. −9.5 U/L, P=0.008, respectively) and the proportion of patients with ALT normalization after treatment was also significantly higher in the dapagliflozin group (80.0% vs. 61.5%, P=0.041). The effect of dapagliflozin with metformin on ALT normalization remained significant after adjustment for confounding variables including body weight loss (odds ratio, 3.489; P=0.046). CONCLUSION: ALT improvement was statistically significant in the dapagliflozin than the DPP4i when combined with metformin and the result was consistent after adjustment for confounding variables including body weight loss.

Risk of Malignancy in Thyroid Incidentalomas Identified by Fluorodeoxyglucose-Positron Emission Tomography

BACKGROUND: Thyroid incidentalomas detected by 2-deoxy-2-18F-fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) have been reported in 1% to 4% of the population, with a risk of malignancy of 27.8% to 74%. We performed a retrospective review of FDG-avid thyroid incidentalomas in cancer screening subjects and patients with nonthyroid cancer. The risk of malignancy in thyroid incidentaloma and its association with the maximal standardized uptake value (SUVmax) in 18F-FDG PET/CT were evaluated to define the predictor variables in assessing risk of malignancy. METHODS: A total of 2,584 subjects underwent 18F-FDG PET/CT for metastatic evaluation or cancer screening from January 2005 to January 2010. Among them, 36 subjects with FDG-avid thyroid incidentalomas underwent further diagnostic evaluation (thyroid ultrasonography-guided fine needle aspiration cytology [FNAC] or surgical resection). We retrospectively reviewed the database of these subjects. RESULTS: Of the 2,584 subjects who underwent 18F-FDG PET/CT (319 for cancer screening and 2,265 for metastatic evaluation), 52 (2.0%) were identified as having FDG-avid thyroid incidentaloma and cytologic diagnosis was obtained by FNAC in 36 subjects. Of the subjects, 15 were proven to have malignant disease: 13 by FNAC and two by surgical resection. The positive predictive value of malignancy in FDG-avid thyroid incidentaloma was 41.7%. Median SUVmax was higher in malignancy than in benign lesions (4.7 [interquartile range (IQR), 3.4 to 6.0] vs. 2.8 [IQR, 2.6 to 4.0], P=0.001). CONCLUSION: Thyroid incidentalomas found on 18F-FDG PET/CT have a high risk of malignancy, with a positive predictive value of 41.7%. FDG-avid thyroid incidentalomas with higher SUVmax tended to be malignant.

Serum Concentrations of Ghrelin and Leptin according to Thyroid Hormone Condition, and Their Correlations with Insulin Resistance

BACKGROUND: Thyroid hormones can influence energy metabolism and insulin sensitivity via their interaction with adipocytokines and gut hormones. The aims of this study were to evaluate differences in serum ghrelin and leptin concentrations according to thyroid hormone levels, and to investigate the correlation of insulin resistance. METHODS: A total of 154 patients (57 hyperthyroid patients, 61 euthyroid patients, and 36 hypothyroid patients; mean age, 47.9 years) were enrolled. Serum leptin, ghrelin, and insulin levels were measured and insulin resistance was calculated using the formula of the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: There were no differences in mean concentrations of ghrelin or leptin among the three groups. There were no significant differences in insulin levels between the groups (P=0.06), although hyperthyroid patients had borderline statistically significantly higher levels of insulin than did euthyroid subjects by post hoc test (26.4 microIU/mL vs. 16.1 microIU/mL, P=0.057). Regarding HOMA-IR index, the mean levels were highest in the hyperthyroid group among those of the three groups (hyperthyroid vs. euthyroid vs. hypothyroid, 6.7 vs. 3.8 vs. 4.4, P=0.068). Plasma levels of ghrelin were significantly negatively correlated with age, insulin, glucose, body mass index (BMI), and HOMA-IR. Plasma levels of leptin showed significant positive correlation with BMI and triglyceride. There were no significant correlations among thyroid hormone, thyrotropin, ghrelin, leptin, or insulin. CONCLUSION: The present study found that serum ghrelin, leptin, and insulin levels didn't differ according to thyroid function conditions. Further studies with larger numbers of patients are required to establish a direct relationship between plasma ghrelin, leptin, and thyroid hormone.

Chronic Alcohol Consumption Results in Greater Damage to the Pancreas Than to the Liver in the Rats

Alcohol consumption increases the risk of type 2 diabetes. However, its effects on prediabetes or early diabetes have not been studied. We investigated endoplasmic reticulum (ER) stress in the pancreas and liver resulting from chronic alcohol consumption in the prediabetes and early stages of diabetes. We separated Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a type-2 diabetic animal model, into two groups based on diabetic stage: prediabetes and early diabetes were defined as occurrence between the ages of 11 to 16 weeks and 17 to 22 weeks, respectively. The experimental group received an ethanol-containing liquid diet for 6 weeks. An intraperitoneal glucose tolerance test was conducted after 16 and 22 weeks for the prediabetic and early diabetes groups, respectively. There were no significant differences in body weight between the control and ethanol groups. Fasting and 120-min glucose levels were lower and higher, respectively, in the ethanol group than in the control group. In prediabetes rats, alcohol induced significant expression of ER stress markers in the pancreas; however, alcohol did not affect the liver. In early diabetes rats, alcohol significantly increased most ER stress-marker levels in both the pancreas and liver. These results indicate that chronic alcohol consumption increased the risk of diabetes in prediabetic and early diabetic OLETF rats; the pancreas was more susceptible to damage than was the liver in the early diabetic stages, and the adaptive and proapoptotic pathway of ER stress may play key roles in the development and progression of diabetes affected by chronic alcohol ingestion.

Clinical Characteristics and Metabolic Features of Patients with Adrenal Incidentalomas with or without Subclinical Cushing's Syndrome

BACKGROUND: The aim of this study was to examine the clinical characteristics of adrenal incidentalomas discovered by computed tomography (CT) and to investigate metabolic features of subclinical Cushing's syndrome (SCS) in patients with adrenal incidentalomas in a tertiary hospital in Korea. METHODS: This retrospective study examined the clinical aspects of 268 patients with adrenal incidentalomas discovered by CT at Soonchunhyang University Bucheon Hospital. Clinical data and endocrine function of the patients as well as histological findings were obtained from medical records, while anatomic characteristics were analyzed by reviewing imaging studies. Hormonal tests for pheochromocytoma, Cushing's syndrome, and aldosterone-secreting adenoma were performed. RESULTS: Most (n=218, 81.3%) cases were nonfunctioning tumors. Of the 50 patients with functioning tumors (18.7%), 19 (7.1%) were diagnosed with SCS, nine (3.4%) with overt Cushing's syndrome, 12 (4.5%) with primary aldosteronism, and 10 (3.7%) with pheochromocytoma. Malignant tumors (both primary and metastatic) were rare (n=2, 0.7%). Body mass index, fasting glucose, hemoglobin A1c, and total cholesterol were significantly higher in patients with SCS in comparison with those with nonfunctioning tumors. The prevalence of type 2 diabetes mellitus and hypertension were significantly higher in patients with SCS compared with those with nonfunctioning tumors. CONCLUSION: Functioning tumors, especially those with subclinical cortisol excess, are commonly found in patients with adrenal incidentalomas, although malignancy is rare. In addition, patients with SCS in adrenal incidentalomas have adverse metabolic and cardiovascular profiles.

A Case of Primary Empty Sella Syndrome with Central Diabetes Insipidus

Primary empty sella syndrome is a phenomenon caused by cerebrospinal fluid filling resulting from the herniation of the subarachnoid space within the sella. The pituitary function of primary empty sella syndrome is usually normal. But sometimes this syndrome causes some degree of pituitary dysfunction associated with hypersecretion or deficiency of pituitary hormone. Central diabetes insipidus with primary empty sella syndrome is rarely reported. Furthermore, most of those cases are accompanied by other pituitary dysfunction. We report here on a 35-year-old female who suffered from polyuria, polydipsia since childhood. She was diagnosed with central diabetes insipidus with primary empty sella syndrome. She had no anterior pituitary dysfunction except mild hyperprolactinemia.

A Case of Stress-Induced Cardiomyopathy in Sheehan's Syndrome / 대한내과학회지

Cardiogenic shock after stress-induced cardiomyopathy is very rare and serious, and a reversible, clinical consequence of untreated adrenal insufficiency that is attributable to Sheehan's syndrome. A 53-year-old female presented with confusion, congestive heart failure, and hypotension. Endocrine testing, prior medical history, and brain MRI confirmed the presence of hypopituitarism and secondary adrenal insufficiency owing to undiagnosed Sheehan's syndrome. After glucocorticoid replacement therapy, her cardiac function recovered completely. Stress-induced cardiomyopathy should be considered as a possible cause of unexplained heart failure in patients with Sheehan's syndrome and adrenal insufficiency.

Metastasis of Colon Cancer to Medullary Thyroid Carcinoma: A Case Report

Metastasis to the primary thyroid carcinoma is extremely rare. We report here a case of colonic adenocarcinoma metastasis to medullary thyroid carcinoma in a 53-yr old man with a history of colon cancer. He showed a nodular lesion, suggesting malignancy in the thyroid gland, in a follow-up examination after colon cancer surgery. Fine needle aspiration biopsy (FNAB) of the thyroid gland showed tumor cell clusters, which was suspected to be medullary thyroid carcinoma (MTC). The patient underwent a total thyroidectomy. Using several specific immunohistochemical stains, the patient was diagnosed with colonic adenocarcinoma metastasis to MTC. To the best of our knowledge, the present patient is the first case of colonic adenocarcinoma metastasizing to MTC. Although tumor-tumor metastasis to primary thyroid carcinoma is very rare, we still should consider metastasis to the thyroid gland, when a patient with a history of other malignancy presents with a new thyroid finding.

Hypertriglyceridemia-Induced Pancreatitis in Poorly Controlled Type 2 Diabetes

A 38-year-old female presented with abdominal pain, radiating to her back. Her medical history included type 2 diabetes, which had been uncontrolled for 8 months. Her initial laboratory tests showed marked hyperglycemia, metabolic acidosis, and elevated serum amylase and lipase levels, although the results were inconclusive in terms of a direct diagnosis of acute pancreatitis (AP). Abdominal computed tomography showed only minimal fluid collection at the pancreas tail. As her serum triglyceride (TG) level was 9,884 mg/dL, we made a working diagnosis of AP due to hypertriglyceridemia, and she was treated with massive hydration with an insulin infusion. Subsequently, she recovered rapidly from the abdominal pain, her serum glucose was controlled, and her serum TG decreased. Hypertriglyceridemia is a well-accepted underlying cause of AP. When extremely high hypertriglyceridemia is detected in patients with type 2 diabetes or metabolic syndrome, complications should be considered and managed.

Association between Cardiac Autonomic Neuropathy, Diabetic Retinopathy and Carotid Atherosclerosis in Patients with Type 2 Diabetes

BACKGROUND: It is not clear whether microangiopathies are associated with subclinical atherosclerosis in type 2 diabetes mellitus (T2DM). We investigated the relation of cardiac autonomic neuropathy (CAN) and other microangiopathies with carotid atherosclerosis in T2DM. METHODS: A total of 131 patients with T2DM were stratified by mean carotid intima-media thickness (CIMT) > or = or or =2. Diabetic microangiopathies were assessed. RESULTS: Patients with CAN comprised 77% of the group with mean CIMT > or =1.0 mm, while they were 29% of the group with CIMT or =1.0 mm, while they were 28% of the group without CIMT thickening (P=0.003). Patients with CAN comprised 51% of the group with > or =2 carotid plaques, while they were 23% of the group with < or =1 carotid plaque (P=0.014). In multivariable adjusted logistic regression analysis, the patients who presented with CAN showed an odds ratio [OR] of 8.6 (95% confidence interval [CI], 1.6 to 44.8) for CIMT thickening and an OR of 2.9 (95% CI, 1.1 to 7.5) for carotid plaques. Furthermore, patients with DR were 3.8 times (95% CI, 1.4 to 10.2) more likely to have CIMT thickening. CONCLUSION: These results suggest that CAN is associated with carotid atherosclerosis, represented as CIMT and plaques, independent of the traditional cardiovascular risk factors in T2DM. CAN or DR may be a determinant of subclinical atherosclerosis in T2DM.

Association between Cardiac Autonomic Neuropathy, Diabetic Retinopathy and Carotid Atherosclerosis in Patients with Type 2 Diabetes

BACKGROUND: It is not clear whether microangiopathies are associated with subclinical atherosclerosis in type 2 diabetes mellitus (T2DM). We investigated the relation of cardiac autonomic neuropathy (CAN) and other microangiopathies with carotid atherosclerosis in T2DM. METHODS: A total of 131 patients with T2DM were stratified by mean carotid intima-media thickness (CIMT) > or = or or =2. Diabetic microangiopathies were assessed. RESULTS: Patients with CAN comprised 77% of the group with mean CIMT > or =1.0 mm, while they were 29% of the group with CIMT or =1.0 mm, while they were 28% of the group without CIMT thickening (P=0.003). Patients with CAN comprised 51% of the group with > or =2 carotid plaques, while they were 23% of the group with < or =1 carotid plaque (P=0.014). In multivariable adjusted logistic regression analysis, the patients who presented with CAN showed an odds ratio [OR] of 8.6 (95% confidence interval [CI], 1.6 to 44.8) for CIMT thickening and an OR of 2.9 (95% CI, 1.1 to 7.5) for carotid plaques. Furthermore, patients with DR were 3.8 times (95% CI, 1.4 to 10.2) more likely to have CIMT thickening. CONCLUSION: These results suggest that CAN is associated with carotid atherosclerosis, represented as CIMT and plaques, independent of the traditional cardiovascular risk factors in T2DM. CAN or DR may be a determinant of subclinical atherosclerosis in T2DM.

The Risk of Metabolic Syndrome According to the White Blood Cell Count in Apparently Healthy Korean Adults

PURPOSE: Considerable amount of interest has been focused on the positive relationship between inflammation and the metabolic syndrome (MS). However, few studies have been performed to evaluate the relationship between baseline white blood cell (WBC) count and future risk for developing MS. Therefore, we investigated whether the baseline plasma levels of WBC count could be associated with future risk for MS in apparently healthy Korean. MATERIALS AND METHODS: A total of 1135 subjects (781 men and 354 women with a mean age of 49 years), who underwent health examinations at Kangbuk Samsung Hospital in both 2002 and 2005 were enrolled. The presence of MS was defined using the modified criteria of the National Cholesterol Education Program Adult Treatment Panel III using BMI instead of waist circumference. RESULTS: The baseline levels of WBC count were significantly higher among incident MS cases than among subjects without MS. The relative risks of incident MS were 1.4, 3.2 and 2.7 for WBC quartiles 2, 3, and 4, respectively, when compared with the first quartile (p-value for trend <0.001). These positive associations persisted after adjustment for baseline body mass index, blood pressure, fasting glucose, high density lipoprotein-cholesterol, triglyceride and homeostatic model assessment-insulin resistance; adjusted relative risk of incident MS for the 2nd, 3rd and 4th quartile groups vs. the lowest quartile were 1.2, 2.4 and 1.7, respectively (p-value for trend =0.011). CONCLUSION: This retrospective cohort study suggests that an elevated WBC count could be associated with incident MS, suggesting that baseline inflammation mirrored by WBC level can impact future MS development.

Impact of Clinicopathologic Factors on Subclinical Central Lymph Node Metastasis in Papillary Thyroid Microcarcinoma

PURPOSE: We evaluated whether the clinicopathological factors of papillary thyroid microcarcinoma (PTMC), especially tumoe size, are associated with subcinical central lymph node metastasis. MATERIALS AND METHODS: A total of 160 patients diagnosed with PTMC who underwent total thyroidectomy with bilateral central lymph node dissection were enrolled in this study. All patients were clinically lymph node negative PTMC. Patients were divided into 2 groups according to the size of tumor (5 mm). Clinicopathologic risk factors for subclinical central lymph node metastasis were analyzed. RESULTS: Subclinical central lymph node metastasis was detected in 61 (38.1%). Patients with tumors 5 mm were independent predictors of subclinical central lymph node metastasis; age, multifocality, bilaterality, extrathyroidal extension, lymphvascular invasion and lymphocytic thyroiditis were not. CONCLUSION: In this study, male and tumor size >5 mm were two independent predictive factors for subclinical central lymph node metastasis in PTMC. These are easier factors to assess before surgery than other factors when planning the central lymph node dissection. However, further long-term follow-up studies are needed to confirm the prognostic significance of subclinical central lymph node metastasis in PTMC.

A case of adrenocortical adenoma with primary hyperaldosteronism and subclinical Cushing's syndrome / 대한내과학회지

Cases of combined primary hyperaldosteronism and subclinical Cushing's syndrome are extremely rare. We identified a left adrenocortical tumor in a 41-year-old woman by computed tomography (CT) during an evaluation for hypokalemia and hypertension. Hormonal assessment demonstrated normal aldosterone concentrations, low plasma renin activity, an increased aldosterone/renin ratio, and normal serum cortisol levels. Selective adrenal venous sampling for the determination of aldosterone concentrations showed an overfunctioning left adrenal gland. Dexamethasone (overnight 1mg, 2 mg, 8 mg) suppression tests showed insuppressible cortisol. We diagnosed the patient as having an aldosterone-producing adrenal adenoma associated with subclinical Cushing's syndrome.

Influence of multiple insulin injections on quality of life, anxiety levels, and depression in type 2 diabetics / 대한내과학회지

BACKGROUND/AIMS: Treatment using multiple daily insulin (MDI) should give diabetic patients many benefits. Nevertheless, few studies have examined the impact of an increased frequency of daily insulin injection on quality of life, anxiety levels, and depression in diabetic patients, and individual's continued compliance with MDI is unclear. This study examined these issues using standardized questionnaires. METHODS: This was a cross-sectional, randomized study. Ninety-nine insulin-treated type 2 diabetic patients (mean age 53.1+/-12 years, mean duration of diabetes 10.3+/-6.5 years) were divided a group (n=50) who injected insulin four times daily (mean age 49.6+/-12.3 years, mean duration of diabetes 6.5+/-6.4 years) and a group (n=49) who injected insulin once or twice daily (mean age 56.4+/-11.6 years, mean duration of diabetes 11.5+/-5.8 years). All patients independently completed the Korean Version of the World Health Organization Quality of Life Scale Abbreviated Version and standardized Hospital Anxiety and Depression Scale for Koreans. RESULTS: No significant differences were evident with respect to age, gender, and duration of diabetes between the two groups (p<0.05). No significant differences were evident in the results of the questionnaires between the two groups, except for the physical health domain (p<0.05). CONCLUSIONS:Multiple daily insulin injections had nearly no influence on quality of life, anxiety levels, or depression in type 2 diabetic patients. Therefore, treatment with MDI should be considered for patients who would benefit from this.

The Effects of Exendin-4 on IRS-2 Expression and Phosphorylation in INS-1 Cells / 당뇨병

BACKGROUND: Insulin receptor substrate 2 (IRS-2) is a key regulator of beta cell proliferation and apoptosis. This study was aimed to investigate effect of the glucolipotoxicity on apoptosis in INS-1 cell, and the effect of Exendin-4, a GLP-1 receptor agonist, on IRS-2 expression in the glucolipotoxicity induced INS-1 cell. The goal was to discover the new action mechanism and function of Exendin-4 in beta cell apoptosis. METHOD: INS-1 cells were cultured in glucolipotoxic condition for 2, 4 or 6 days and were categorized as G groups. Another group in which 50 nM Exendin-4 was added to INS-1 cells, cultured in glucolipotoxic condition, were named as Ex-4 groups. We investigated the expression of IRS-2 by RT-PCR, phosphorylated IRS-2 and phosphorylated Akt protein levels by western blot. We measured the apoptosis ratio of INS-1 cell in glucolipotoxic condition by TUNEL staining in both groups. RESULT: IRS-2 expression of INS-1 cells decreased with correlation to the time of exposure to glucolipotoxic condition. pIRS-2 and pAkt protein levels decreased in the similar pattern in glucolipotoxicity group. However, this effect of glucolipotoxicity on INS-1 cell was inhibited by the Exendin-4 treatment. In the Ex-4 groups, IRS-2 expression, pIRS-2 and pAkt protein levels remained at the similar level to low glucose condition state. Also, apoptosis induced by glucolipotoxicity was suppressed by Exendin-4 treatment significantly. CONCLUSION: We showed that the long-term treatment of Exendin-4 inhibited the apoptosis of beta cells significantly in glucolipotoxic condition and that this effect of Exendin-4 was related with IRS-2 and Akt among the beta cell's intracellular signal transduction pathway.

The Effects of Mistletoe Extract and Anti-cancer Drugs on the Apoptosis of Gastric Cancer Cells

PURPOSE: Mistletoe extract was widely used for cancer treatment as complementary or alternative therapy in European area from early twenty century. It is currently used as alternative anti-cancer remedy by piecemeal in domestic medical group, however, the anti-cancer mechanism of mistletoe extract was not known precisely until now. In this study the effect of mistletoe extract on gastric cancer was studied vis cell line experiments. MATERIALS AND METHODS: The SNU719 gastric cancer cell line was used, and ABNOBAviscum-Q and ABNOBAviscum-F were treated to cells as mistletoe extract, or 5-FU and cisplatin were used with mistletoe extract. The cell viability and cell death rate were estimated by CCK-8 assay kit and lactate dehydrogenase (LDH) assay kit in each. Caspase 3 assay kit was used to measure caspase 3 activity. The protein expression amounts of Bcl2, p53, and PTEN were estimated through Western blot analysis. RESULTS: The co-treatments of mistletoe extract Q/F and 5-FU/cisplatin decreased lesser cell viability than only mistletoe treat. Caspase 3 activity was increased 4~6 times in co-treatment of mistletoe extracts and 5-FU than control. Bcl2 protein expression was reduced by mistletoe extracts or anti-cancer drugs, further more, the co-treatment of mistletoe extracts and 5-FU/cisplatin diminished more the expression than only mistletoe treatment. Mistletoe extracts did not affect the protein expressions of p53 and PTEN. CONCLUSION: It was concluded that the anti-cancer mechanism of mistletoe extracts was made by caspase 3 activation and lowered Bcl2 expression, and this apoptosis inducing mechanism was independent to p53.

(99m)Tc Generator Safety Simulation Based on GEANT4 / 의학물리

Technisium ((99m)Tc) is one of the most widely used radioactive isotopes for diagnosis in nuclear medicine. In general, technisium is produced inside the so called (99m)Tc generator which is usually made out of lead to shield relatively high energy radiation from (99)Mo and its daughter nuclide (99m)Tc. In this paper, a GEANT4 simulation is carried out to test the safety of the (99m)Tc generator, taking the Daiichi product with radioactivity of 500 mCi as an example. According to the domestic regulation on radiation safety, the dose at 10 cm and 100 cm away from the surface of shielding container should not exceed 2.0 mSv/h and 0.02 mSv/h, respectively. The simulated dose turned out to be less than the limit, satisfying the domestic regulation.

Best surrogate marker for insulin resistance in middle aged non-diabetic Korean: Chungju metabolic syndrome study / 대한내과학회지

BACKGROUND: To investigate the best surrogate marker for insulin resistance in the non-diabetic middle-aged population in Korea. METHODS: This study was performed from February to April 2003-2005 in adults over 40 years of age living in Chungju City, South Korea, selected by stratified random cluster sampling. We analyzed the data from a total 6,149 non-diabetic subjects that completed a survey consisting of anthropometric measurement and blood chemistry. We defined the highest quartile of the homeostasis model for insulin resistance (HOMA-IR) as the insulin resistant group in our study population. We also analyzed the correlation of various anthropometric (body mass index, waist circumference, waist to hip ratio, waist to height ratio) and biochemical parameters (total cholesterol to HDL cholesterol ratio, non-HDL cholesterol level, triglycerides to HDL cholesterol ratio and level of triglycerides) with insulin resistance using simple and multiple regression analysis for detecting the insulin resistance group. RESULTS: By simple regression analysis, among the anthropometric parameters including the body mass index, waist circumference, waist to hip ratio, waist to height ratio, and the biochemical parameters, including the total cholesterol to HDL cholesterol ratio, non-HDL cholesterol level, triglyceride to HDL cholesterol ratio and triglycerides level, the body mass index was the best surrogate marker for insulin resistance (95% CI 1.215-1.262). The cut-off value of the body mass index was 24.6 kg/m2 (male; 24.7, female; 24.6 kg/m2), with a sensitivity of 62.6% and specificity of 66.9%. Multiple logistic regression analysis for insulin resistance also gave the same results. Furthermore, the cut-off value of the body mass index for the metabolic syndrome as defined by NCEP-ATP III was also 24.1 kg/m2 (male; 24.0, female; 24.2 kg/m2). CONCLUSIONS: Our study results suggest that the body mass index was the best surrogate marker for insulin resistance of a non-diabetic population and its cut-off value was approximately 24 kg/m2.