Ji Sun Nam

Konkuk University, Seoul, Seoul, South Korea

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Publications (25)49.25 Total impact

  • Article: Simple and rapid discrimination of embB codon 306 mutations in Mycobacterium tuberculosis clinical isolates by a real-time PCR assay using an LNA-TaqMan probe.
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    ABSTRACT: Single nucleotide polymorphisms in the codon 306 of embB gene are most frequently reported in ethambutol-resistant Mycobacterium tuberculosis clinical isolates. Here, we report a simple and rapid real-time PCR assay using a locked nucleic acid (LNA)-TaqMan probe for discriminating the embB306 mutations. The use of a 15-bp chimeric LNA/DNA probe led to a relatively higher level of sensitivity and fluorescence signal in the wild-type embB306 ATG codon. Therefore, the mutant alleles were easily distinguishable from the wild-type allele by their distinctive amplification curve shapes without a melting analysis of the PCR product. This system was fast and less than 0.1 pg of genomic DNA per reaction were needed for detection. Because the results from this real-time assay were absolutely consistent with those from DNA sequencing, it can be effectively applied as a simple and rapid method for primary screening of embB306 mutations that occur frequently in ethambutol-resistant and/or multidrug-resistant M. tuberculosis isolates.
    Journal of microbiological methods 12/2012; · 2.43 Impact Factor
  • Article: Visceral adiposity and leptin are independently associated with C-reactive protein in Korean type 2 diabetic patients
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    ABSTRACT: The inflammatory marker, C-reactive protein (CRP) is associated with long-term cardiovascular events. The aim of the study was to investigate the factors contributing to serum CRP, assess the relationship between CRP level and the parameters of visceral obesity, and examine the association between leptin and CRP level in type 2 diabetic patients. 150 patients with type 2 diabetes were enrolled. These patients were recently diagnosed (≤3years) with type 2 diabetes and were drug naive or taking sulfonylureas only. BMI, WC, and serum concentration of CRP, glycosylated hemoglobin (HbA1c), glucose, lipids, plasminogen activator-1 (PAI-1) and leptin were measured. Insulin resistance was estimated by the insulin resistance index of homeostasis model assessment (HOMA-IR). We measured the carotid intima-media thickness (IMT). Fat mass assessed by dual-energy X-ray absorptionmetry and abdominal fat distribution was determined by CT scan. Serum concentration of CRP was significantly correlated with BMI (γ=0.257, P<0.01), WC (γ=0.293, P<0.01), fat mass (γ=0.213, P<0.01), total adipose tissue (γ=0.263, P<0.01), visceral adipose tissue (γ=0.296, P<0.01), insulin (γ=0.189, P=0.047), PAI-1 (γ=0.206, P<0.01), leptin (γ=0.322, P<0.01), mean IMT (γ=0.132, P=0.042), and HOMA-IR (γ=0.172, P=0.045). After adjustment for age and gender, multiple regression analysis showed that serum CRP was significantly associated with leptin (β=0.326, P=0.01) and visceral adipose tissue (β=0.265, P=0.035). In conclusion, serum CRP level is significantly associated with obesity, especially the visceral adipose tissue, and serum leptin is another important independent factor associated with CRP in Korean type 2 diabetic patients. KeywordsCRP-Leptin-Visceral adipose tissue-Type 2 diabetes
    Acta Diabetologica 04/2012; 47(2):113-118. · 2.78 Impact Factor
  • Article: Molecular characterization of drug-resistant and -susceptible Mycobacterium tuberculosis isolated from patients with tuberculosis in Korea.
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    ABSTRACT: We investigated the causal relationship between genotype and phenotype of drug-resistant Mycobacterium tuberculosis isolates obtained from patients with pulmonary tuberculosis (TB) in Korea. Of 80 isolates tested, 17, 20, 1, and 7 isolates were mono-resistant to ethambutol (EMB), isoniazid (INH), pyrazinamide (PZA), and rifampicin (RFP), respectively, and 31 isolates (38.8%) were multidrug-resistant (MDR). Sequencing analysis showed that 78% (32/41) of RFP-resistant strains had mutations in the rifampicin resistance-determining region (RRDR) of rpoB, and the mutation at rpoB531 (59.4%) was most abundant. In 52 INH-resistant strains, mutations were found mostly at C-15T (n = 21, 40.4%) in the inhA promoter region as well as at katG315 (n = 12, 23.1%). Mutations at embB306 were mostly found in 26.7% (12/45) of EMB-resistant isolates. New mutations found here in MDR isolates include rpoB523 (Gly523Glu) and embB319 (Tyr319Ser). Consequently, mutations in the rpoB531, C-15T in the inhA promoter region, embB306, and katG315 would be a useful marker for rapid detection of MDR M. tuberculosis isolates in Korea.
    Diagnostic microbiology and infectious disease 11/2011; 72(1):52-61. · 2.45 Impact Factor
  • Article: Molecular cloning, purification, and characterization of a superoxide dismutase from a fast-growing Mycobacterium sp. Strain JC1 DSM 3803.
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    ABSTRACT: A cytosolic superoxide dismutase (SOD) was purified and characterized from a fast-growing Mycobacterium sp. strain JC1 DSM 3803 grown on methanol. The native molecular weight of the purified SOD was estimated to be 48 kDa. SDS-PAGE revealed a subunit of 23 kDa, indicating that the enzyme is a homodimer. The enzyme activity was inhibited by H(2)O(2) and azide. The purified SOD contained 1.12 and 0.56 g-atom of Mn and Fe per mol of enzyme, respectively, suggesting that it may be a Fe/Mn cambialistic SOD. The apo-SOD reconstitution study revealed that Mn salts were more specific than Fe salts in the SOD activity. The gene encoding the SOD was identified from the JC1 cosmid genomic library by PCR screening protocol. The cloned gene, sodA, had an open reading frame (ORF) of 624 nt, encoding a protein with a calculated molecular weight of 22,930 Da and pi of 5.33. The deduced SodA sequence exhibited 97.6% identity with that of Mycobacterium fortuitum Mn-SOD and clustered with other mycobacterial Mn-SODs. A webtool analysis on the basis of SOD sequence and structure homologies predicted the SOD as a tetrameric Mn-SOD, suggesting that the protein is a dimeric Mn-SOD having tetramer-specific sequence and structure characteristics.
    The Journal of Microbiology 06/2011; 49(3):399-406. · 1.10 Impact Factor
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    Article: Response: predictive clinical parameters for the therapeutic efficacy of sitagliptin in korean type 2 diabetes mellitus (diabetes metab j 2011;35:159-65).
    Diabetes & metabolism journal 06/2011; 35(3):300-1.
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    Article: Predictive clinical parameters for the therapeutic efficacy of sitagliptin in korean type 2 diabetes mellitus.
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    ABSTRACT: Sitagliptin is a highly selective dipeptidyl peptide-4 (DPP-4) inhibitor that increases blood levels of active glucagon-like peptide (GLP)-1 and glucose-dependent insulinotrophic polypeptide (GIP), resulting in increased insulin secretion. While studies conducted in other countries have indicated the efficacy and safety of using sitagliptin to treat type 2 diabetes mellitus (T2DM), its predictors of effects to sitagliptin are not well understood. Therefore, we evaluated the predictive clinical parameters for the therapeutic benefits of sitagliptin when added to an ongoing metformin or sulfonylurea therapy in Korean T2DM subjects. We obtained data from 251 Korean T2DM subjects who had recently started taking sitagliptin as add-on therapy. Exclusion criteria included any insulin use. Changes in HbA1c (ΔHbA1c) and fasting plasma glucose (ΔFPG) were assessed by comparing baseline levels prior to sitagliptin administration to levels 12 and 24 weeks after treatment. Responders were defined as subjects who experienced decrease from baseline of >10% in ΔHbA1c or >20% in ΔFPG levels at 24 weeks. We classified 81% of the subjects (204 out of 251) as responders. The responder group had a lower mean body mass index (23.70±2.40 vs. 26.00±2.26, P≤0.01) and were younger (58.83±11.57 years vs. 62.87±12.09 years, P=0.03) than the non-responder group. In Korean T2DM subjects, sitagliptin responders had lower body mass index and were younger compared to non-responders.
    Diabetes & metabolism journal 04/2011; 35(2):159-65.
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    Article: Effect of pioglitazone on serum concentrations of osteoprotegerin in patients with type 2 diabetes mellitus.
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    ABSTRACT: Osteoprotegerin (OPG) acts as an important regulatory molecule in atherosclerosis. Recent studies report that thiazolidinediones could affect OPG expression. We investigated the relationship between OPG and inflammatory cytokines and the effects of pioglitazone (a PPARγ (PPARG) agonist) versus metformin on serum OPG levels in type 2 diabetic patients. Sixty-seven type 2 diabetic patients were included in this study. They were assigned to pioglitazone (15 mg/day, n=34) or metformin (1000 mg/day, n=33) during 24 weeks. Various anthropometric and metabolic parameters, OPG, interleukin 6 (IL6), C-reactive protein (CRP), adiponectin, and homeostasis model assessment of insulin resistance (HOMA-IR), were measured at baseline and at 6 months of treatment. Serum OPG levels correlated significantly with fasting plasma glucose (FPG), HbAlc, HOMA-IR, IL6, and CRP, and inversely correlated with adiponectin after adjusting for age (P<0.05). Multiple regression analysis showed that FPG, HbAlc, and adioponectin were independently correlated with OPG level. After 6 months of treatment, the reduction in FPG and HbAlc levels was similar between the two groups. Pioglitazone treatment significantly increased body mass index (P<0.05) and waist circumference (P<0.05) and decreased triglycerides (P<0.05) and HOMA-IR (P<0.01). The adiponectin concentration was increased (P<0.05), and OPG and CRP levels were decreased in the pioglitazone group (P<0.05), but were unchanged in the metformin group. The changes in serum OPG in the pioglitazone group showed significant correlation with changes in FPG, HbAlc, and adiponectin. In type 2 diabetic patients, pioglitazone decreases OPG levels, and this decrease in OPG levels might be associated with the increase in adiponectin.
    European Journal of Endocrinology 10/2010; 164(1):69-74. · 3.42 Impact Factor
  • Article: Insulin resistance independently influences arterial stiffness in normoglycemic normotensive postmenopausal women.
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    ABSTRACT: Cardiovascular disease risk increases after menopause, which may be related to insulin resistance, and arterial stiffness is a significant predictor of atherosclerosis. We investigated the relationships among insulin resistance, adiponectin, and arterial stiffness in normoglycemic normotensive postmenopausal women. From 9,555 participants who had routine health checkups, 455 normoglycemic normotensive postmenopausal women were enrolled. Serum concentrations of glucose, total cholesterol, triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) and adiponectin were measured. Insulin resistance was estimated by the insulin resistance index of homeostasis model assessment (HOMA-IR). Pulse wave velocity (PWV) was evaluated to assess arterial stiffness. The women were stratified into three groups according to their HOMA-IR values, and comparisons were made among the three groups. There were significant differences in metabolic parameters between the groups. The mean age, body mass index, waist circumference, fasting plasma glucose, TG, systolic blood pressure (SBP), diastolic blood pressure (DBP), aortic PWV, and peripheral PWV increased sequentially with the degree of insulin resistance. Meanwhile, HDL-C and adiponectin levels decreased with the worsening of insulin resistance. Age, body mass index, fasting plasma glucose, TG, insulin, SBP, HOMA-IR, aortic PWV, and peripheral PWV were significantly higher in women with central obesity, and HDL-C and adiponectin were significantly lower in women with central obesity. Aortic PWV and peripheral PWV were significantly correlated with age, waist circumference, total cholesterol, SBP, DBP, insulin, and HOMA-IR, but adiponectin was not associated with PWV. The results of multiple regression analysis indicated that SBP, DBP, and insulin resistance were independently correlated with PWV. Insulin resistance was independently associated with PWV in normoglycemic normotensive postmenopausal women.
    Menopause (New York, N.Y.) 03/2010; 17(4):779-84. · 3.08 Impact Factor
  • Article: Insulin resistance is independently associated with peripheral and autonomic neuropathy in Korean type 2 diabetic patients.
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    ABSTRACT: In addition to chronic hyperglycemia, insulin resistance itself has been proposed to cause a diabetic neuropathy. We evaluated the role of insulin resistance in the pathogenesis of peripheral and autonomic neuropathy in patients with type 2 diabetes. Eighty-six patients with type 2 diabetes were evaluated for the anthropometric and biochemical profiles, and Kitt value was calculated from insulin tolerance test to assess the insulin resistance. Various autonomic function tests, nerve conduction velocity, and quantitative sensory tests were performed to assess autonomic and peripheral neuropathy. In univariate analysis, both autonomic and peripheral neuropathy were significantly associated with glycemic exposure index (GE index), HDL-cholesterol, duration of DM, and Kitt value. In stepwise linear regression analysis, GE index was an independent predictor of autonomic and peripheral neuropathy (β = 0.643, P < 0.001; β = 0.207, P = 0.013, respectively), and Kitt value was also an independent factor for the autonomic and peripheral neuropathy (β = - 0.306, P < 0.001; β = - 0.329, P < 0.001, respectively). Low HDL-cholesterol increased the odds ratio for peripheral neuropathy. Insulin resistance is independently associated with peripheral and autonomic neuropathy in Korean Type 2 diabetic patients along with hyperglycemia and HDL-cholesterol.
    Acta Diabetologica 02/2010; 49(2):97-103. · 2.78 Impact Factor
  • Article: Cloning, expression and characterization of the catalase-peroxidase (KatG) gene from a fast-growing Mycobacterium sp. strain JC1 DSM 3803.
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    ABSTRACT: The gene encoding a catalase-peroxidase (KatG) was cloned from chromosomal DNA of a fast-growing Mycobacterium sp. strain JC1 DSM 3803. The nucleotide sequence of a 5.7 kb EcoRI fragment containing the katG and its flanking regions was determined. The fragment (5,706 bps) contained two complete open reading frames (ORFs) encoding putative ferric uptake regulator A (FurA) and KatG proteins. The cloned gene, katG, had an ORF of 2241 nt, encoding a protein with calculated molecular mass of 81,748 Da. The furA was located in the upstream of the katG with the same transcriptional direction and there was a 38 bp gap space between them. The deduced KatG and FurA protein sequences showed significant homologies to KatG2 and Fur2 of Mycobacterium smegmatis and clustered with other mycobacterial KatG and Fur-like proteins in phylogenetic trees, respectively. The recombinant KatG overproduced in Escherichia coli was nearly indistinguishable from the native JC1 catalase-peroxidase in enzymatic properties and also possessed the resistance to organic solvents, indicating that the cloned katG truly encodes the Mycobacterium sp. JC1 catalase-peroxidase. Difference spectroscopy revealed Mn(II) binding near the haem of the KatG. Transcript analysis of the furA-katG using RT-PCR suggests that the katG is independently transcribed from the furA.
    Journal of biochemistry 11/2009; 147(4):511-22. · 1.95 Impact Factor
  • Article: Adiponectin is independently associated with apolipoprotein B to A-1 ratio in Koreans.
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    ABSTRACT: Apolipoprotein B to A-1 (apo B/A-1) ratio is reportedly a better predictor of atherosclerotic vascular disease than low-density lipoprotein cholesterol (LDL-C). The aim of this study was to assess the association of serum apo B/A-1 ratio with insulin resistance and adiponectin in patients with different grades of glucose intolerance. Patients were divided according to glucose tolerance into 3 groups: normal glucose tolerance without metabolic syndrome (n = 229), impaired fasting glucose (subjects with fasting plasma glucose level between 100 and 125 mg/dL, n = 658), and type 2 diabetes mellitus (n = 381). Serum concentrations of apo B, apo A-1, glucose, total cholesterol (TC), triglycerides, and high-density lipoprotein cholesterol (HDL-C) and adiponectin were measured. Insulin resistance was estimated by the homeostasis model assessment of insulin resistance index (HOMA-IR). There were significant differences in metabolic parameters among the groups, including waist circumference, insulin, HOMA-IR, and apo B/A-1 ratio, which increased sequentially with glucose intolerance, whereas adiponectin level decreased with increasing severity of glucose intolerance. The apo B/A-1 ratio was significantly correlated with TC, triglycerides, LDL-C, HDL-C, adiponectin, and HOMA-IR in normal glucose tolerance, impaired fasting glucose, and type 2 diabetes mellitus. Multiple regression analysis showed that apo B/A-1 ratio was significantly associated with TC, LDL-C, HDL-C, and adiponectin. In conclusion, apo B/A-1 ratio was significantly associated with insulin resistance according to glucose intolerance; and serum adiponectin was an important independent factor associated with apo B/A-1 ratio in Koreans.
    Metabolism: clinical and experimental 11/2009; 59(5):677-82. · 2.59 Impact Factor
  • Article: Usefulness of brachial-ankle pulse wave velocity as a predictive marker of multiple coronary artery occlusive disease in Korean type 2 diabetes patients.
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    ABSTRACT: Multiple coronary artery occlusive disease (multiple CAOD) is the most fatal and frequently observed coronary artery disease in type 2 diabetes patients, but no simple, non-invasive screening tool is available yet. The aim of this study is to evaluate the arterial stiffness in type 2 diabetes patients using brachial-ankle pulse wave velocity (baPWV), to demonstrate the correlation between arterial stiffness and multiple CAOD, and to suggest the cutoff point of baPWV for predicting multiple CAOD in Korean type 2 diabetes patients. One hundred and eighty-one diabetes and 262 non-diabetes patients were enrolled in the study. Routine anthropometric and serologic data were collected. baPWV was measured the day before coronary angiography, and the severity of CAOD was assessed with Gensini score after angiography. baPWV and Gensini score were significantly increased in diabetes patients and Gensini score had a positive correlation with baPWV. Subjects in the highest tertile of baPWV showed odds ratio of 3.06 for multiple CAOD compared to the lowest tertile. In ROC curve, baPWV at 1635 cm/s showed 73% sensitivity and 75% specificity with AUC 0.76 in diabetes patients in detecting multiple CAOD. Therefore, baPWV may be utilized a screening tool for predicting multiple CAOD, especially in type 2 diabetes patients.
    Diabetes research and clinical practice 05/2009; 85(1):30-4. · 2.16 Impact Factor
  • Article: A novel PHEX mutation in a Korean patient with sporadic hypophosphatemic rickets.
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    ABSTRACT: Mutations including nonsense mutations, missense mutations, splicing-site mutations, insertions, and deletions in phosphate regulating genes on the X-chromosome (PHEX) are known to be responsible for X-linked hypophosphatemic rickets. The PHEX gene encodes an endopeptidase that is involved in phosphate regulation. Herein we present a female patient with sporadic hypophosphatemic rickets harboring a novel deletion mutation (c.1586_1586+1delAG; p.Glu529GlyfsX41) at exon 14 and intron 14 junction, which caused a premature termination at codon 569 and possibly produced a truncated PHEX protein. The laboratory and radiologic findings of the patient are reviewed to correlate the impact of the two-base deletion mutations at the exon-intron junction.
    Annals of clinical and laboratory science 02/2009; 39(2):182-7. · 0.96 Impact Factor
  • Article: Relationship of low-density lipoprotein (LDL) particle size to thyroid function status in Koreans.
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    ABSTRACT: Dyslipidaemia is a well-known manifestation of thyroid dysfunction. Recently, small low-density lipoprotein (LDL) particle size has been linked with development of cardiovascular disease. To better understand the effects of thyroid dysfunction on the development of cardiovascular disease, we examined LDL particle size and lipid profiles in subjects with different thyroid function. Included were 46 patients with overt hypothyroidism, 57 patients with subclinical hypothyroidism, 46 patients with overt hyperthyroidism, 51 patients with subclinical hyperthyroidism, and 110 age- and sex-matched healthy control subjects. We measured LDL particle size and lipid profiles in these subjects. No significant differences were found in LDL particle size between the groups with different thyroid function. Serum total cholesterol and LDL-cholesterol levels were significantly higher in the cases of hypothyroidism than in the cases of hyperthyroidism and the healthy control subjects. Serum triglyceride levels were higher in subjects with overt hypothyroidism than in those with overt hyperthyroidism or healthy control subjects. LDL particle size, the emerging risk factor for atherosclerosis, did not appear to be significantly affected by the degree of thyroid dysfunction. Increased risk of atherosclerosis in hypothyroidism does not appear to be associated with LDL particle size, the non-traditional cardiovascular risk factor.
    Clinical Endocrinology 10/2008; 71(1):130-6. · 3.17 Impact Factor
  • Article: The activation of NF-kappaB and AP-1 in peripheral blood mononuclear cells isolated from patients with diabetic nephropathy.
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    ABSTRACT: We evaluated the role of oxidative stress in diabetic nephropathy by measuring intracellular reactive oxygen species (ROS) and redox-sensitive transcription factors in isolated peripheral mononuclear cells (PBMC) in 66 diabetic patients with or without diabetic nephropathy (Groups III and II, respectively) and 49 normal controls (Group I). Stimulated ROS was significantly higher in Group III compared to Group II (increment of H(2)O(2)-induced ROS production: 21.8+/-2.2% vs. 11.1+/-2.0%; increment of PMA-induced ROS production 23.5+/-4.5% vs. 21.6+/-2.2%; both respectively), and the activity of nuclear factor-kappa B (NF-kappaB) and activator protein-1 (AP-1), but not specificity protein 1 (Sp1) was significantly higher in Group III than in Group II (2.53-fold vs. 2.0-fold vs. 1.43-fold, respectively). Both PBMC- and urinary TGF-beta1 levels were higher in Group III than Group II (3.23+/-0.39 ng/g vs. 1.99+/-0.68 ng/g in PBMCs, 16.88+/-6.84 (ng/g Cr) vs. 5.61+/-1.57 (ng/g Cr) in urine, both respectively), and they correlated with the activity of NF-kappaB and AP-1 and 24-h urine albumin excretion (UAE). Increased intracellular ROS generation in PBMCs of diabetic patients is involved in the pathogenesis of diabetic nephropathy via activation NF-kappaB and AP-1 and an increased expression of TGF-beta1.
    Diabetes research and clinical practice 08/2008; 81(1):25-32. · 2.16 Impact Factor
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    Article: Visceral fat thickness predicts fatty liver in Koreans with type 2 diabetes mellitus.
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    ABSTRACT: Our aim was to study whether visceral adiposity is a predictor of diabetic fatty liver in Korean type 2 diabetes mellitus. In this study, abdominal ultrasonography was used to assess the presence of fatty liver in 1,898 patients with type 2 diabetes. We measured visceral fat thickness by high-resolutional ultrasonography and insulin resistance by Kitt. Half of the cohort had a fatty liver (50.2%). High visceral fat thickness had the highest odds ratio for developing fatty liver in both sexes (odds ratio [S.D]: 3.14 [2.24-4.69], p<0.00 in male, 2.84 [2.04-3.93], p<0.00 in female). In addition, visceral fat thickness of 42.45 and 37.7 mm in men and women, respectively, were chosen as the discriminating value to predict the presence of fatty liver with a sensitivity of 71% and 73% and a specificity of 70% and 70% in men and women, respectively. The area under the receiver-operating characteristics curve was 0.759 in men and 0.764 in women. Therefore we could conclude that the degree of visceral adiposity predicts the presence of fatty liver type 2 diabetes mellitus, whether centrally obese or not, suggesting that hepatic fat accumulation in a diabetic fatty liver may be influenced by visceral fat accumulation regardless of waist circumference.
    Journal of Korean Medical Science 04/2008; 23(2):256-61. · 0.99 Impact Factor
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    Article: Cerebral arterial pulsatility and insulin resistance in type 2 diabetic patients.
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    ABSTRACT: Diabetic patients have a threefold risk for cerebrovascular disease compared with nondiabetic controls. The aim of the present study was to investigate the association of insulin resistance with the pulsatility index (PI) of cerebral arteries in type 2 diabetic patients. We compared a group of 90 patients with stroke-free, type 2 diabetes and an age- and sex-matched control group of 45 healthy subjects without diabetes. We then evaluated the PI of the middle cerebral artery (MCA) by transcranial Doppler ultrasonography (TCD), and insulin resistance was determined by a short insulin tolerance test. The PI was significantly higher in diabetic patients than in healthy controls (p<0.05) and also higher in patients with insulin resistance than that seen in insulin sensitive diabetic patients (p<0.05). The PI of the MCA was significantly correlated with age (R=0.465, p<0.01), duration of diabetes (R=0.264, p=0.025) and hypertension (R=0.285, p=0.015) and inversely correlated with the insulin resistance index (Kitt: R=-0.359, p=0.030). A multiple regression analysis was performed with PI as the dependent variable and insulin resistance as an independent variable along with known clinical risk factors. Age (beta=0.393, p<0.01) and duration of diabetes (beta=0.274, p=0.043) exhibited a significant independent contribution to PI. PI could be a useful marker in the detection of diabetic cerebrovascular changes, and insulin resistance showed correlations with PI, but age and the duration of diabetes contributed independently to the variability in the PI.
    Diabetes research and clinical practice 02/2008; 79(2):237-42. · 2.16 Impact Factor
  • Article: The effects of pioglitazone on cerebrovascular resistance in patients with type 2 diabetes mellitus.
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    ABSTRACT: Atherosclerosis is one of the major causes of morbidity and mortality in patients with type 2 diabetes mellitus. Pioglitazone has been reported to have antiatherogenic effects. The aim of this study was to investigate whether pioglitazone affects pulsatility index (PI) of the cerebral arteries and the carotid intima-media thickness in type 2 diabetic patients. A total of 40 type 2 diabetic patients were included in this study. They were divided into 2 groups: the pioglitazone-treated group (pioglitazone 15 mg/d with gliclazide 80-320 mg/d for 12 weeks) and the gliclazide-treated group (gliclazide 80-320 mg/d for 12 weeks). Transcranial Doppler ultrasonography was performed for each cerebral artery, and PI was calculated as (systolic velocity-diastolic velocity)/mean velocity. The pioglitazone treatment significantly increased high-density lipoprotein cholesterol and decreased triglyceride levels and insulin resistance. This study revealed that the change in mean intima-media thickness was not significant in both groups, but the change in PI was significantly decreased with pioglitazone compared to gliclazide. In conclusion, pioglitazone decreased PI and improved cerebrovascular resistance in type 2 diabetic patients.
    Metabolism 09/2007; 56(8):1081-6. · 2.66 Impact Factor
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    Article: Bilateral peripheral facial palsy in a patient with Human Immunodeficiency Virus (HIV) infection.
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    ABSTRACT: Neurological complications are important causes of morbidity and mortality in patients with human immunodeficiency virus (HIV) infection. They can occur at any stage of the disease and can affect any level of the central or peripheral nervous systems. In the literature, several cases of HIV-associated facial paralysis have been reported; however, bilateral facial palsy is rarely reported. In this paper, we present the first case in Korea, of a bilateral facial palsy occurring as the first clinical manifestation of HIV infection.
    Yonsei Medical Journal 11/2006; 47(5):745-7. · 1.14 Impact Factor
  • Article: Clinical and biochemical characteristics of nonobese type 2 diabetic patients with glutamic acid decarboxylase antibody in Korea.
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    ABSTRACT: We evaluated the prevalence of glutamic acid decarboxylase autoantibody (GADA) in nonobese patients with type 2 diabetes mellitus in Korea and investigated the characteristics of GADA-positive and GADA-negative patients. Two years later, we assessed the progression of beta-cell function in these patients. Of the 647 nonobese patients with type 2 diabetes mellitus enrolled in the study, 10.1% was positive for GADA. Glutamic acid decarboxylase antibody-positive patients had lower fasting and stimulated C-peptide levels compared with GADA-negative patients (1.70 +/- 0.72 vs 1.24 +/- 0.59 microg/L, P < .001; 2.59 +/- 1.51 vs 1.99 +/- 0.82 microg/L, P < .001). Patients treated with insulin had lower fasting and stimulated C-peptide levels than those not treated (1.13 +/- 0.52 vs 1.66 +/- 0.73 microg/L, P = .002; 1.85 +/- 0.69 vs 2.49 +/- 0.91 microg/L, P = .004) and had higher titers of GADA (30.5 +/- 7.3 vs 6.0 +/- 4.8 U/mL, P < .001). In terms of progression of beta-cell function, fasting and stimulated C-peptide levels were significantly lower in GADA-positive patients after 2 years (from 1.24 +/- 0.59 to 0.95 +/- 0.54 microg/L, P = .004; from 1.99 +/- 0.82 to 1.61 +/- 0.77 microg/L, P = .007), whereas no such difference was observed in the GADA-negative patients. We demonstrate that a significant proportion of Korean patients may be positive for GADA; this is consistent with studies of white subjects, although disagrees with previous reports on Korean subjects. By assessing the presence of GADA in Korean type 2 diabetic patients, we are able to predict their course of beta-cell function and identify in advance those who are likely to require insulin treatment.
    Metabolism 08/2006; 55(8):1107-12. · 2.66 Impact Factor

Institutions

  • 2009–2012
    • Konkuk University
      Seoul, Seoul, South Korea
  • 2006–2012
    • Yonsei University Hospital
      • Department of Internal Medicine
      Seoul, Seoul, South Korea
  • 2008
    • Hallym University
      • College of Medicine
      Seoul, Seoul, South Korea
  • 2006–2008
    • Yonsei University
      • Department of Internal Medicine
      Seoul, Seoul, South Korea