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D S Choi

Publications and source records attributed to D S Choi.

At least 19 recordsLinked to original sources

Prevalence and trends of metabolic syndrome in Korea: Korean National Health and Nutrition Survey 1998-2001.

BACKGROUND: Metabolic syndrome (MetS) is a major international health problem. Limited information is available about the prevalence of MetS in Asia, especially in Korea. OBJECTIVE: To examine the prevalence and trends of MetS in a Korean population. In addition, we investigated the risk factors associated with MetS. DESIGN AND PARTICIPANTS: A total of 7445 participants aged >/=20 years from the Korean National Health and Nutrition Survey (KNHNS) 1998 and 5964 participants from the KNHNS 2001 were included in this analysis. The KNHNS is a cross-sectional health survey of a nationally representative sample of the Korean population. The prevalence of MetS was determined using the National Cholesterol Education Program Adult Treatment Panel III criteria and the Asia-Pacific criteria for obesity based on waist circumference (APC-WC). RESULTS: Using the ATP III criteria, the age-adjusted prevalence of MetS among Korean adults was 15.7% (13.7% male, 17.8% female) in 1998 and 14.4% (13.0% male, 16.2% female) in 2001. Using the APC-WC criteria, the prevalence was 21.6% (19.4% male, 23.9% female) in 1998 and 21.4% (20.1% male, 23.4% female) in 2001. Of the five MetS components, increasing trends were found between 1998 and 2001 in the prevalence of hypertriglyceridaemia, low high-density lipoprotein cholesterol and central obesity for both men and women. Age, sex, body mass index and a family history of diabetes were associated with MetS. CONCLUSIONS: These results from a representative sample show that MetS is common in Korean adults. A systemic public health programme is required to prevent future increases in diabetes and cardiovascular complications.

Adult↗

Glioblastoma cell death induced by asiatic acid.

Asiatic acid (AA), a triterpene, is known to be cytotoxic to several tumor cell lines. AA induces dose- and time-dependent cell death in U-87 MG human glioblastoma. This cell death occurs via both apoptosis and necrosis. The effect of AA may be cell type-specific as AA-induced cell death was mainly apoptotic in colon cancer RKO cells. AA-induced glioblastoma cell death is associated with decreased mitochondrial membrane potential, activation of caspase-9 and -3, and increased intracellular free Ca2+. Although treatment of glioblastoma cells with the caspase inhibitor zVAD-fmk completely abolished AA-induced caspase activation, it did not significantly block AA-induced cell death. AA-induced cell death was significantly prevented by an intracellular Ca2+ inhibitor, BAPTA/AM. Taken together, these results indicate that AA induces cell death by both apoptosis and necrosis, with Ca2+-mediated necrotic cell death predominating.

Amino Acid Chloromethyl Ketones↗

Serum adiponectin, interleukin-10 levels and inflammatory markers in the metabolic syndrome.

We examined the association between interleukin-10 (IL-10), adiponectin levels and inflammatory markers such as interleukin-6 (IL-6) and high-sensitive C-reactive protein (hsCRP). Furthermore, the association of these anti-/pro-inflammatory cytokine levels with the metabolic syndrome was investigated. The study subjects were composed of 312 Korean individuals without diabetes. Serum adiponectin level was associated with hsCRP (r=-0.21, P<0.001), IL-6 (r=-0.13, P<0.05) and IL-10 (r=-0.22, P<0.001) levels. Subjects without the metabolic syndrome showed higher adiponectin (17.03 microg/ml versus 13.85 microg/ml, P<0.001) and IL-10 (4.74 pg/ml versus 4.34 pg/ml, P=0.014) levels, and lower serum hsCRP (0.38 microg/ml versus 0.66 microg/ml, P=0.001) and IL-6 (0.94 pg/ml versus 1.32 pg/ml, P=0.009) levels compared to those with the metabolic syndrome. In multiple logistic regression analysis, the metabolic syndrome was associated with sex, age, waist circumference, systolic blood pressure, HDL cholesterol, triglyceride, fasting blood glucose and interleukin-10. Furthermore, serum adiponectin levels are associated with serum hsCRP, IL-6 and IL-10 levels. These results suggest that adiponectin might be associated with the metabolic syndrome through regulation of pro-/anti-inflammatory cytokines.

Adiponectin↗

Progesterone-dependent release of transforming growth factor-beta1 from epithelial cells enhances the endometrial decidualization by turning on the Smad signalling in stromal cells.

Endometrial decidualization results from the differentiation of stromal cells in an ovarian steroid-sensitive manner. Human endometrial tissues obtained from fertile women at various stages of the menstrual cycle were subjected to immunohistochemistry to localize the components of the transforming growth factor-beta (TGF-beta) system. TGF-beta receptor-I and -II expression was higher in stromal cells than in epithelial cells during the secretory phase while no such variation was observed during the proliferative phase. The expression of phosphorylated Smad3 (pSmad2/3), an activated form of a component of the TGF-beta signalling pathway, and translocation of pSmad2/3 from the cytoplasm to the nucleus were more pronounced in secretory endometrium. In coculture of human endometrial epithelial with stromal cells, each isolated from the proliferative endometrium, administration of progesterone stimulated decidualization as well as TGF-beta signalling activation in stromal cells. Progesterone also significantly elevated the concentration of TGF-beta1 in the coculture medium. Careful manipulation of the coculture, i.e. selective addition and omission of the cellular components, showed that this progesterone-induced increase in secretion of TGF-beta1 come mainly from epithelial cells. Moreover, administration of TGF-beta1 (10 ng/ml) directly to cultured stromal cells enhanced the expression of prolactin as well as pSamd2/3 even without progesterone. Taken together, our present data support the notion that progesterone induces stromal decidualization indirectly, i.e. by enhancing the expression and secretion of TGF-beta1 from epithelial cells. The secreted, epithelial-derived TGF-beta1 then acts on adjacent stromal cells, at least in part, to turn on Smad signalling that could lead to stromal decidualization.

Adenomyoma↗

Prevalence of erectile dysfunction in Korean men with Type 2 diabetes mellitus.

AIMS: We investigated the prevalence and risk factors for developing erectile dysfunction (ED) in 1312 Korean men with diabetes in a multicentre study. METHODS: We used the modified International Index for Erectile Function-5 criteria to identify mild, moderate and complete ED. A standardized face-to-face questionnaire was used by trained interviewers, and validated against telephone interviews. We recorded the duration of diabetes, level of glycaemic control, vital signs, complications, exercise and alcohol and smoking habits, and diabetes treatments used. Results The mean age and median duration of diabetes were 53.8 +/- 6.65 and 6 years (range 1-43), respectively. The mean HbA(1c) and fasting glucose levels were 7.9 +/- 1.65% and 8.6 +/- 2.82 mmol/l, respectively. The overall prevalences of mild, moderate, complete ED and all ED (mild-to-complete) were 20.1, 19.5, 25.8 and 65.4%, respectively. ED was more common with age, reaching 79.3% in men aged > 60 years. Subjects aged > 60 years and with a duration of diabetes > 10 years were at greatest risk for all ED (OR = 10.4, 95% CI 5.8-18.5, P < 0.001) and complete ED (OR = 13.2, 95% CI 7.3-23.9, P < 0.001) when compared with the reference group (age 40-50 years with duration < 6 years). Age, duration of diabetes, HbA(1c), insulin use, neuropathy and macrovascular complications were positively associated with ED, but alcohol consumption and exercise habits were negatively associated. CONCLUSIONS: The prevalence of complete ED was approximately six times higher than in the general population.

Adult↗

Prevalence of diabetes and impaired fasting glucose in Korea: Korean National Health and Nutrition Survey 2001.

OBJECTIVE: The purpose of this study was to estimate the prevalence of diabetes and impaired fasting glucose (IFG) and their association with risk factors in the Korean population. RESEARCH DESIGN AND METHODS: The Korean National Health and Nutrition Survey 2001 was a nationally representative survey with a stratified multistage sampling design. Data from a comprehensive questionnaire, a physical examination, and blood tests were obtained from 5,844 Korean adults (2,513 men and 3,331 women) aged >20 years. RESULTS: The age-adjusted prevalence of diabetes in this Korean population was 7.6%, and the age-adjusted prevalences of previously diagnosed diabetes and newly diagnosed diabetes were 4.4 and 3.3%, respectively (fasting plasma glucose > or = 7.0 mmol/l). Overall, these results indicate that 8.1% or 1.4 million Korean men and 7.5% or 1.3 million Korean women have diabetes. The age-adjusted prevalence of IFG was 23.9%, using the new American Diabetes Association criteria (fasting plasma glucose 5.6-6.9 mmol/l). Diabetes prevalence increased with age and peaked in the oldest age-group; however, IFG prevalence did not show the same trend. Diabetes was found to be associated with age, BMI, blood pressure, triglyceride, HDL cholesterol, education levels, alcohol consumption, exercise, and a family history of diabetes. CONCLUSIONS: This study shows that diabetes and IFG are common in Korea, and about one-half of diabetes cases remain undiagnosed. These results emphasize the need to develop an urgent public program to improve the detection, prevention, and treatment of diabetes.

Adult↗

Effect of PPAR-alpha and -gamma agonist on the expression of visfatin, adiponectin, and TNF-alpha in visceral fat of OLETF rats.

A variety of adipocytokines and peptides secreted from adipocytes have been considered to play a crucial role in obesity, insulin resistance, and type 2 diabetes. Recently, visfatin, a new adipocytokine, known as a pre-B cell colony-enhancing factor, has been isolated from visceral fat deposits. It has been shown to activate insulin receptors in a manner different from insulin. To understand the role of adipocytokines in improving insulin sensitivity via activation of the nuclear receptor peroxisome proliferator-activated receptor-alpha (PPAR-alpha) and -gamma (PPAR-gamma), we examined the expression of visfatin, adiponectin, and TNF-alpha in visceral fat depots of Otsuka Long-Evans Tokushima fatty (OLETF) rats from early to advanced diabetic stage (from 28 to 40 weeks of age). Serum glucose and insulin concentrations significantly (P<0.05) decreased in rosiglitazone or fenofibrate-treated OLETF rats compared to untreated OLETF rats. Rosiglitazone significantly increased serum adiponectin concentration from 20 to 40 weeks of age (P<0.05), whereas fenofibrate reduced TNF-alpha concentration. The expression of visfatin and adiponectin mRNA in visceral fat deposits was elevated by rosiglitazone or fenofibrate treatments when compared to untreated OLETF rats (P<0.05), whereas, TNF-alpha mRNA was down-regulated by these drugs (P<0.05). These results suggest that rosiglitazone and fenofibrate may prevent type 2 diabetes by regulating adipocytokines including visfatin, adiponectin, and TNF-alpha.

Adiponectin↗

Effects of green tea consumption on inflammation, insulin resistance and pulse wave velocity in type 2 diabetes patients.

In this study, we examined the effects of green tea on inflammation and arterial stiffness in type 2 diabetes patients. As results, inflammatory markers, such as hsCRP and IL-6, were unchanged after green tea consumption, and neither were blood glucose, lipid profiles, insulin resistance, or serum adiponectin levels. Furthermore, tea consumption did not improve baPWV. These results suggest that the above-described mechanisms are unlikely to explain the cardiovascular risk reduction by tea consumption observed in epidemiological studies.

Beverages↗

Growth and photosynthetic responses of two pine species (Pinus koraiensis and Pinus rigida) in a polluted industrial region in Korea.

We investigated the effects of pollutants on two pine species (Pinus koraiensis and Pinus rigida) in an industrial region in Korea, using a physiological approach. The concentrations of fluorine (F) and chlorine (Cl) in the atmosphere, in precipitation and soil water at the damaged site were all significantly higher than at a control site. Moreover, the concentrations of F, Cl and Mn in pine needles were significantly higher, and essential elements and chlorophyll in needles were significantly lower at the damaged site than at the control site. The photosynthetic capacities, shoot length and survival statistics of needles of the two pines were all significantly reduced at the damaged site compared to the control site, especially P. rigida. Based on our comparison of photosynthetic responses and the concentrations of F, Cl and Mn in needles of the two pine species, P. koraiensis is more resistant to excess Mn in its needles than P. rigida.

Air Pollutants↗

Structural determination of the low-coverage phase of Al on Si(001) surface.

The atomic structure of Al layer on Si(001)-(2 x 1) surface has been studied by coaxial impact collision ion scattering spectroscopy. When 0.5 monolayer (ML) of Al atoms are adsorbed on Si(001) at room temperature, it is found that Al adatoms are dimerized and Al ad-dimers are oriented parallel to the underlying Si dimers at the position of centering T3 site with a height of 1.02 Angstroms from the first layer of Si(001). The bond length of the Al dimer is 2.67 Angstroms. With increasing Al coverage up to one ML, Al ad-dimers still occupied near T3 site and the next favorable site is near HH site.

Journal Article↗

Structural analysis of the reconstructed Si(001)-C surface.

The atomic structure of reconstructed Si(001)c(4 x 4)-C surface has been studied by coaxial impact collision ion scattering spectroscopy. When the 100L of ethylene (C(2)H(4)) molecules have been exposed on Si(001)-(2 x 1) surface at 700 degrees C, it is found that C atoms cause the ordering of missing Si dimer defects and occupy the fourth layer of Si(001) directly below the bridge site. Our results provide the support for the previous model in which a missing dimer structure is accompanied by C incorporation into the subsurface.

Journal Article↗

Association among serum ferritin, alanine aminotransferase levels, and metabolic syndrome in Korean postmenopausal women.

We examined the relationships among serum ferritin, alanine aminotransferase (ALT) levels, and cardiovascular risk factors of metabolic syndrome in Korean postmenopausal women. We conducted a cross-sectional study of 959 postmenopausal women without an apparent cause of liver disease. Metabolic syndrome was defined as the presence of at least 3 of the following: elevated blood pressure, low high-density lipoprotein cholesterol, elevated serum triglycerides, elevated plasma glucose, and abdominal obesity. Serum ferritin and ALT levels were found to be correlated (r=0.374, P<.001) and to be associated with the components of metabolic syndrome. Subjects with metabolic syndrome showed significantly higher serum ferritin (74.7+/- 2.0 vs 59.6+/- 2.0 ng/mL, P<.001) and ALT levels (21.3+/-1.6 vs 18.7+/-1.5 IU/L, P<.001). Moreover, the greater the number of metabolic syndrome components present, the higher were the serum ferritin and ALT levels (P<.001). Multiple regression analysis showed that serum ALT levels are significantly associated with serum ferritin levels, waist circumference, fasting blood glucose, age, and white blood cell count (adjusted R(2)=0.147). Elevated iron stores were positively associated with serum ALT levels and metabolic syndrome in Korean postmenopausal women.

Aged↗

Serum osteoprotegerin levels are associated with inflammation and pulse wave velocity.

OBJECTIVE: We examined the association between serum osteoprotegerin (OPG) levels, systemic inflammation and arterial stiffness in normal and diabetic patients. PATIENTS AND MEASUREMENTS: The study subjects comprised 49 newly diagnosed diabetic patients and 72 age- and sex-matched normal glucose controls. Anthropometric parameters, blood pressure, fasting blood glucose (FBG), lipid profiles, serum OPG, high-sensitive C-reactive protein (hsCRP), interleukin-6 (IL-6) and brachial-ankle pulse wave velocity (baPWV) were measured. RESULTS: Serum OPG levels (6.1 +/- 1.4 vs. 5.4 +/- 1.3 pmol/l, P = 0.011) and baPWV (1562 +/- 354 vs. 1399 +/- 257 cm/s, P = 0.004) were significantly higher in the diabetic group than in the normal glucose group. Serum OPG levels in normal and diabetic patients correlated significantly with systolic blood pressure (r = 0.20, P = 0.035), FBG (r = 0.30, P = 0.002), right baPWV (r = 0.22, P = 0.021), left baPWV (r = 0.26, P = 0.006), homeostasis model assessment insulin resistance (HOMA-IR) (r = 0.19, P = 0.045), IL-6 (r = 0.32, P = 0.001) and hsCRP (r = 0.21, P = 0.027) after adjusting for age and sex. Multiple regression analysis showed that serum OPG level was significantly associated with age, FBG, IL-6, systolic blood pressure, triglyceride and hsCRP (R(2) = 0.299). CONCLUSIONS: In summary, serum OPG and baPWV levels are elevated in diabetic patients and serum OPG levels are significantly associated with inflammation and arterial stiffness.

Biomarkers↗

Relationship between serum adiponectin concentration, pulse wave velocity and nonalcoholic fatty liver disease.

OBJECTIVES: We aimed to investigate the relationship between nonalcoholic fatty liver disease (NAFLD), serum adiponectin concentration and brachial-ankle pulse wave velocity (baPWV) as a risk marker for atherosclerosis. METHODS: A total of 213 nonalcoholic subjects (67 males, 146 females) participated in this study. Division of subjects into the NAFLD group or the normal group was based on the existence of fatty liver detected by sonography. RESULTS: Serum adiponectin levels in the NAFLD group were significantly lower than those in the normal group. After adjusting for age, body-mass index (BMI) and the homeostasis model of assessment (HOMA), there was a significant negative correlation between NAFLD and serum adiponectin level only in females (r = -0.22, P = 0.008). Multiple logistic regression analysis showed a tendency of inverse correlation between NAFLD and serum adiponectin level in females (P = 0.055). After adjustment for age, BMI and HOMA value, serum adiponectin levels were inversely correlated with serum alanine aminotransferase (ALT) and gamma-glutamyltranspeptidase (GGT) levels (r = -0.199 (P = 0.004) and r = -0.282 (P < 0.001)). On the other hand, baPWV in the NAFLD group was also significantly higher than that in the normal group in females (P = 0.005). Individual levels of serum ALT, aspatate aminotransferase (AST), alkaline phosphatase (ALP) and GGT were positively correlated with baPWV after adjusting for age, sex, BMI, HOMA and systolic blood pressure (P < 0.05). CONCLUSION: Serum adiponectin level and baPWV were significantly associated with NAFLD and various liver enzymes, especially in females.

Adiponectin↗

Inflammation, insulin resistance, and glucose intolerance in acute myocardial infarction patients without a previous diagnosis of diabetes mellitus.

We examined the prevalence of impaired glucose metabolism and its association with inflammation and insulin resistance (IR) in acute myocardial infarction (AMI) patients without a previous diagnosis of diabetes. This prospective study enrolled 52 AMI patients, and 75-g oral glucose tolerance testing was performed on 30 patients at discharge and again 3 months later. We also measured serum adiponectin, high sensitive C-reactive protein, and IL-6 on both occasions. Data were compared with those of 30 type 2 diabetic patients without a history of AMI. Forty percent and 36.7% of AMI patients had impaired glucose tolerance (IGT) at discharge and at 3 months, respectively. The corresponding proportions for newly diagnosed diabetes are 33.0% and 30.0%. At discharge, AMI patients with IGT or diabetes showed higher high sensitive C-reactive protein and IL-6 levels compared with AMI patients with normal glucose tolerance or control type 2 diabetic patients. Furthermore, AMI patients with IGT or diabetes exhibited higher IR and lower serum adiponectin levels than AMI patients with normal glucose tolerance at 3 months after discharge. Previously undiagnosed diabetes and IGT are common in Korean patients with AMI. These glycometabolic abnormalities are associated with inflammation, IR, and serum adiponectin levels.

Adiponectin↗

Comparison of serum concentrations of C-reactive protein, TNF-alpha, and interleukin 6 between elderly Korean women with normal and impaired glucose tolerance.

This study was performed to compare concentrations of pro-inflammatory cytokines, such as interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha) as well as acute-phase protein, such as C-reactive protein (CRP) between subjects with normal glucose tolerance (NGT) and impaired glucose tolerance (IGT). The purpose of this study was to verify whether the pro-inflammatory cytokine-induced acute-phase response is a pathogenic mechanism in type 2 diabetes in elderly Korean women. A total of 1737 elderly subjects aged over 60 years participated in a population based study in Seoul, Korea (SWS Study 1999). Amongst them, a total of 232 non-smoking and non-diabetic female subjects aged 60-89 years was randomly selected and compared with each other. Higher serum high-sensitivity CRP (hs-CRP) concentrations were shown in subjects with IGT than those with normal glucose tolerance (median 1.2 versus 0.9, P < 0.05). Moreover, a relationship between serum hs-CRP concentrations and many components of the metabolic syndrome were detected. Serum pro-inflammatory cytokine IL-6 or TNF-alpha concentrations, however, were neither increased in subjects with IGT nor closely correlated with the components of the metabolic syndrome. In multiple regression analysis with stepwise selection method using hs-CRP as a dependent variable, it was found that white blood cell (WBC) counts, body mass index (BMI), fasting insulin, post-load 2h glucose, hematocrit and LDL cholesterol were significant independent variables. Our study confirms that increased acute-phase reaction is associated with impaired glucose tolerance and the metabolic syndrome in elderly Korean women. However, the hypothesis that pro-inflammatory cytokine-induced systemic inflammation is an early metabolic defect prior to onset of type 2 diabetes, is not supported in our study of elderly Korean women.

Acute-Phase Reaction↗

Relationship between brachial-ankle pulse wave velocity and cardiovascular risk factors of the metabolic syndrome.

In this study, we investigated the association between brachial-ankle pulse wave velocity (baPWV), a novel non-invasive means of measuring atherosclerosis, and the cardiovascular risk factors of the metabolic syndrome. The study group comprised of 368 Koreans without history of diabetes or hypertension. Anthropometric parameters, blood pressure, fasting blood glucose (FBG), lipid profiles, ankle-brachial pressure index (ABI), and baPWV were measured in each subject. ABI and baPWV levels were higher in men than in women. ABI and baPWV levels were not correlated with each other. In women, baPWV was closely associated with the cardiovascular risk factors of the metabolic syndrome. Women with the metabolic syndrome showed higher baPWV levels compared to those without the metabolic syndrome (1540 +/- 281 versus 1312 +/- 223, P < 0.001). Multiple regression analysis showed that baPWV was significantly associated with systolic blood pressure, age, sex, waist circumference, and FBG (adjusted R2 = 0.548). The present study shows that baPWV is significantly associated with the features of the metabolic syndrome in Korean women.

Ankle Joint↗

Serum adiponectin concentrations predict the developments of type 2 diabetes and the metabolic syndrome in elderly Koreans.

OBJECTIVE: To determine whether low serum adiponectin concentrations are able to predict the future developments of type 2 diabetes and the metabolic syndrome using the National Cholesterol Education Programme (NCEP) criteria. We also investigated the stability of adiponectin levels and the relationships between baseline adiponectin levels and changes in the parameters related to the metabolic syndrome over a period of 3 years. PATIENTS AND MEASUREMENTS: This prospective cohort study included 372 elderly Koreans who participate in the SWS (South-West Seoul) study, which was conducted in 1999 and 2002 in Seoul, Korea. Fasting and postchallenge 2-h plasma glucose, body mass index (BMI), waist-to-hip ratio (WHR), blood pressure, lipid profiles and serum adiponectin data obtained in 1999 and 2002 were examined. RESULTS: The within-person variation between 1999 and 2002 of serum adiponectin was not significant (P = 0.61). Serum adiponectin was closely correlated with the risks factors of cardiovascular disease (CVD), that is negatively with BMI, WHR, blood pressure, triglyceride and blood glucose levels, and positively with high density lipoprotein (HDL)-cholesterol levels. Subjects with the metabolic syndrome showed lower serum adiponectin concentrations than those without the metabolic syndrome (P < 0.0001). Baseline adiponectin levels were found to be correlated with subsequent changes in WHR, low density lipoprotein (LDL)-cholesterol, fasting and postload 2-h glucose over the 3-year period, after adjusting for baseline values. Multiple logistic regression analysis showed that lower baseline serum adiponectin concentrations were significantly associated with the developments of type 2 diabetes and the metabolic syndrome after adjusting for age, sex, obesity, history of impaired fasting glucose (IFG) or impaired glucose tolerance (IGT), hypertension and dyslipidaemia. CONCLUSIONS: Reduced concentrations of adiponectin were found to be independently associated with increased risk of both type 2 diabetes and the metabolic syndrome in elderly Koreans.

Adiponectin↗