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Choi JH, Jeon HJ, Choi KM, Kang JK. Metal–organic frameworks for visible light absorption via anion substitution. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm16245h] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Choi KM, Kim SJ, Baek JH, Kang SJ, Boo YC, Koh JS. Cosmetic efficacy evaluation of an anti-acne cream using the 3D image analysis system. Skin Res Technol 2011; 18:192-8. [DOI: 10.1111/j.1600-0846.2011.00553.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2011] [Indexed: 11/29/2022]
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Ki MR, Yun SK, Choi KM, Hwang SY. Identification and characterization of the acid phosphatase HppA in Helicobacter pylori. J Microbiol Biotechnol 2011; 21:483-93. [PMID: 21617345 DOI: 10.4014/jmb.1101.01017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
An acid phosphatase (HppA) activated by NH4Cl was purified 192- and 34-fold from the periplasmic and membrane fractions of Helicobacter pylori, respectively. SDS-polyacrylamide gel electrophoresis revealed that HppA from the latter appears to be several kilodaltons larger in molecular mass than from the former by about 24 kDa. Under acidic conditions (pH< or =4.5), the enzyme activity was entirely dependent on the presence of certain mono- and/or divalent metal cations (e.g., K+, NH4 +, and/or Ni2+). In particular, Ni2+ appeared to lower the enzyme's Km for the substrates, without changing Vmax. The purified enzyme showed differential specificity against nucleotide substrates with pH; for example, the enzyme hydrolyzed adenosine nucleotides more rapidly at pH 5.5 than at pH 6.0, and vice versa for CTP or TTP. Analyses of the enzyme's N-terminal sequence and of an HppA- H. pylori mutant revealed that the purified enzyme is identical to rHppA, a cloned H. pylori class C acid phosphatase, and shown to be the sole bacterial 5'-nucleotidase uniquely activated by NH4Cl. In contrast to wild type, HppA- H. pylori cells grew more slowly. Strikingly, they imported Mg2+ at a markedly lowered rate, but assimilated urea rapidly, with a subsequent increase in extracellular pH. Moreover, mutant cells were much more sensitive to extracellular potassium ions, as well as to metronidazole, omeprazole, or thiophenol, with considerably lowered MIC values, than wild-type cells. From these data, we suggest that the role of the acid phosphatase HppA in H. pylori may extend beyond 5'-nucleotidase function to include cation-flux as well as pH regulation on the cell envelope.
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Yang SJ, Hwang SY, Choi HY, Yoo HJ, Seo JA, Kim SG, Kim NH, Baik SH, Choi DS, Choi KM. Serum selenoprotein P levels in patients with type 2 diabetes and prediabetes: implications for insulin resistance, inflammation, and atherosclerosis. J Clin Endocrinol Metab 2011; 96:E1325-9. [PMID: 21677040 DOI: 10.1210/jc.2011-0620] [Citation(s) in RCA: 134] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT AND OBJECTIVE The dysregulation of hepatokines may be associated with the pathogenesis of insulin resistance and type 2 diabetes. A recent study has suggested that selenoprotein P (SeP), a novel hepatokine, may play a role in the regulation of glucose metabolism and insulin sensitivity. We examined the relationship between circulating SeP levels and clinical parameters associated with insulin resistance in humans. PARTICIPANTS AND METHODS We compared serum SeP concentrations in 100 subjects with diverse glucose tolerance statuses. Furthermore, we evaluated the relationship between SeP and cardiometabolic risk factors including insulin resistance, high-sensitivity C-reactive protein, and carotid intima-media thickness. RESULTS Serum SeP concentrations were significantly higher in patients with type 2 diabetes or prediabetes than those with normal glucose tolerance (all P < 0.01) and decreased in a stepwise manner [1032.4 (495.9-2149.4) vs. 867.3 (516.3-1582.7) vs. 362.0 (252.5-694.5), P = 0.004]. In addition, overweight and obese subjects had significantly increased SeP levels compared with lean subjects (P = 0.002). Spearman's partial correlation analysis adjusted for age and gender showed a significant relationship between SeP and cardiometabolic factors including body mass index, waist circumference, systolic blood pressure, triglycerides, glucose, hemoglobin A1c, aspartate aminotransferase, and insulin resistance. Furthermore, in multiple regression analyses, SeP showed an independent association with carotid intima-media thickness as well as high-sensitivity C-reactive protein, even after adjustment for other confounding factors. CONCLUSIONS Circulating SeP concentrations were elevated in patients with glucose metabolism dysregulation and were related to various cardiometabolic parameters including insulin resistance, inflammation, and atherosclerosis.
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Choi KM, Jeon HJ, Kang JK, Yaghi OM. Heterogeneity within Order in Crystals of a Porous Metal–Organic Framework. J Am Chem Soc 2011; 133:11920-3. [DOI: 10.1021/ja204818q] [Citation(s) in RCA: 204] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Choi YJ, Choi JH, Choi KM, Kang JK. Covalent organic frameworks for extremely high reversible CO2uptake capacity: a theoretical approach. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c0jm02891f] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lim KI, Yang SJ, Kim TN, Yoo HJ, Kang HJ, Song W, Baik SH, Choi DS, Choi KM. The association between the ratio of visceral fat to thigh muscle area and metabolic syndrome: the Korean Sarcopenic Obesity Study (KSOS). Clin Endocrinol (Oxf) 2010; 73:588-94. [PMID: 20618345 DOI: 10.1111/j.1365-2265.2010.03841.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
OBJECTIVE A relationship between visceral fat accumulation and metabolic syndrome (MetS) has been established. However, the effect of a relative increase in visceral fat and a decrease in muscle mass on metabolic disorders has not been investigated. The aim of the present study was to examine the association between the ratio of visceral fat to thigh muscle area (VMR) and MetS in Korean adults. STUDY SUBJECT/MEASUREMENTS: A total of 264 age-and gender-matched subjects recruited from the Korean Sarcopenic Obesity Study (KSOS), an ongoing prospective observational cohort study, were categorized into four groups based on their body mass index (BMI) and VMR. We measured visceral fat area and thigh muscle area using computed tomography. RESULTS Subjects with MetS showed a significantly higher VMR than those without MetS. In both obese and nonobese groups, the subjects with a higher VMR had a higher prevalence of MetS than those in the lower VMR groups. VMR was significantly related to components of the metabolic syndrome, especially in women, and was positively correlated with a number of MetS components in both men and women. In multiple logistic regression analysis, the odds ratio for MetS was 6·72 (highest vs lowest quartile, 95% confidence interval, 1·60-28·14) after an adjustment of potential confounders, including BMI and waist-to-hip ratio. CONCLUSION VMR is significantly increased in subjects with MetS and independently associated with MetS. These results suggest that the VMR may be a potential indicator for MetS risk in Korean adults.
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Choi JH, Choi KM, Jeon HJ, Choi YJ, Lee Y, Kang JK. Acetylene Gas Mediated Conjugated Microporous Polymers (ACMPs): First Use of Acetylene Gas as a Building Unit. Macromolecules 2010. [DOI: 10.1021/ma1007144] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Choi KM, Lee SJ, Choi JH, Park TJ, Park JW, Shin WH, Kang JK. Facile fabrication of networked patterns and their superior application to realize the virus immobilized networked pattern circuit. Chem Commun (Camb) 2010; 46:8609-11. [DOI: 10.1039/c0cc03323e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bharucha AE, Kulkarni A, Choi KM, Camilleri M, Lempke M, Brunn GJ, Gibbons SJ, Zinsmeister AR, Farrugia G. First-in-human study demonstrating pharmacological activation of heme oxygenase-1 in humans. Clin Pharmacol Ther 2009; 87:187-90. [PMID: 19956091 DOI: 10.1038/clpt.2009.221] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Heme oxygenase (HO)-1 degrades heme and protects against oxidative stress, but it has not been pharmacologically induced in humans. In this randomized study of 10 healthy volunteers, hemin (3 mg/kg intravenously in 25% albumin) was shown to increase plasma HO-1 protein concentration four- to fivefold and HO-1 activity ~15-fold relative to baseline at 24 and 48 h (placebo -56.41 +/- 6.31 (baseline), 69.79 +/- 13.00 (24 h), 77.44 +/- 10.62 (48 h) vs. hemin -71.70 +/- 9.20 (baseline), 1,126.20 +/- 293.30 (24 h), 1,192.20 +/- 333.30 (48 h)) in four of five subjects as compared with albumin alone (P </= 0.03). This represents the overcoming of a fundamental hurdle to HO-1 research in humans.
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Koo JR, Choi KM, Lee SJ, Kim YK, Kwon SJ. Impedance spectroscopy of a molecular memory cell with a redox-active component. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:6988-6992. [PMID: 19908712 DOI: 10.1166/jnn.2009.1664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report the frequency dependent impedance spectroscopy of an Al/Al2O3/ASA-15 monolayer/Ti/Al molecular memory cell. As a result of comparing the memory cell with a control device that does not contain ASA-15 molecules, we confirmed that its impedance properties were originated from the ASA-15 monolayer. By examining the Cole-Cole plot for the fabricated memory cell, we also found that the response of the memory cell can be explained in terms of an equivalent circuit model with a contact resistance R(s) in series with an impedance Z(ox) at the Al oxide layer and an impedance Z(LB) at the ASA-15 monolayer.
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Yoo HJ, Park MS, Kim TN, Yang SJ, Cho GJ, Hwang TG, Baik SH, Choi DS, Park GH, Choi KM. A Ubiquitous Chronic Disease Care system using cellular phones and the internet. Diabet Med 2009; 26:628-35. [PMID: 19538239 DOI: 10.1111/j.1464-5491.2009.02732.x] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS The rapidly increasing prevalence of chronic diseases is an important challenge to healthcare systems worldwide. To improve the quality and efficiency of chronic disease care, we investigated the effectiveness and applicability of the Ubiquitous Chronic Disease Care (UCDC) system using cellular phones and the internet for overweight patients with both Type 2 diabetes and hypertension. METHODS We conducted a randomized, controlled clinical trial over 3 months that included 123 patients at a university hospital and a community public health centre. RESULTS After 12 weeks, there were significant improvements in HbA(1c) in the intervention group (7.6 +/- 0.9% to 7.1 +/- 0.8%, P < 0.001) compared with the control group (7.4 +/- 0.9% to 7.6 +/- 1.0%, P = 0.03). Furthermore, we observed a significant reduction in systolic and diastolic blood pressure, as well as improvements in total cholesterol, low-density lipoprotein-cholesterol and triglyceride levels in the intervention group. Furthermore, there was a significant increase in adiponectin levels in the intervention group compared with the control group, although high-sensitivity C-reactive protein and interleukin-6 levels did not change in either group. CONCLUSIONS The novel UCDC system presented in this paper improved multiple metabolic parameters simultaneously in overweight patients with both Type 2 diabetes and hypertension.
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Choi KM, Kim TN, Yoo HJ, Lee KW, Cho GJ, Hwang TG, Baik SH, Choi DS, Kim SM. Effect of exercise training on A-FABP, lipocalin-2 and RBP4 levels in obese women. Clin Endocrinol (Oxf) 2009; 70:569-74. [PMID: 18710473 DOI: 10.1111/j.1365-2265.2008.03374.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Lipocalin family proteins, including adipocyte fatty acid-binding protein (A-FABP), lipocalin-2 and retinol-binding protein 4 (RBP4), have recently been identified as novel adipokines associated with obesity, type 2 diabetes and the metabolic syndrome. We have evaluated the effect of exercise training on lipocalin family proteins and inflammatory markers. STUDY SUBJECTS Thirty obese Korean women and 15 age-matched nonobese control subjects were studied. DESIGN Concentrations of the lipocalin family proteins were compared between obese and nonobese women and were evaluated before and 3 months after an exercise programme consisting of aerobic exercise (45 min/session, 300 kcal/day) and muscle strength training (20 min/session, 100 kcal/day) five times a week. RESULTS Obese women exhibited higher A-FABP levels compared to nonobese women (21.4 +/- 6.4 microg/l vs. 13.6 +/- 4.4 microg/l, P < 0.001). However, neither lipocalin-2 nor RBP4 levels were significantly different between the two groups, although the difference in lipocalin-2 was marginally significant (P = 0.054). Circulating A-FABP levels were significantly associated with body mass index (BMI), waist circumference, triglyceride, alanine aminotransferase (ALT), lipocalin-2 and high-sensitivity C-reactive protein (hsCRP) levels. After 3 months of the exercise training programme, serum A-FABP levels decreased significantly from 21.4 +/- 6.4 microg/l to 19.3 +/- 6.8 microg/l (P = 0.038), along with a reduction in weight, BMI, waist circumference, fasting glucose and total cholesterol levels. There was no significant change in the lipocalin-2 and RBP4 levels, although IL-6 levels increased after the exercise programme. CONCLUSION Exercise training with weight loss induced a significant reduction in circulating A-FABP levels in obese Korean women.
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Yoo HJ, An HG, Park SY, Ryu OH, Kim HY, Seo JA, Hong EG, Shin DH, Kim YH, Kim SG, Choi KM, Park IB, Yu JM, Baik SH. Use of a real time continuous glucose monitoring system as a motivational device for poorly controlled type 2 diabetes. Diabetes Res Clin Pract 2008; 82:73-9. [PMID: 18701183 DOI: 10.1016/j.diabres.2008.06.015] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 06/04/2008] [Accepted: 06/11/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE The use of a real time continuous glucose monitoring system (RT-CGM) was studied as a behavior modification tool and the effectiveness of a RT-CGM in glucose control for patients with type 2 diabetes was determined. METHODS We conducted a prospective, open-label, randomized, controlled clinical trial in 65 patients with poorly controlled type 2 diabetes (8.0</=HbA1c</=10%) over a 3-month period. The intervention group was monitored monthly with a RT-CGM (three days at a time for 3 months) and the control group continued self-monitoring blood glucose (SMBG) at least four times a week for 3 months. RESULTS The HbA1c of the RT-CGM group was significantly reduced after 12 weeks compared with the SMBG group (9.1+/-1.0% to 8.0+/-1.2% vs. 8.7+/-0.7% to 8.3+/-1.1%, respectively; P=0.004). In the RT-CGM group, there was a significant reduction in total daily calorie intake, weight, body mass index (BMI), and postprandial glucose level, and a significant increase in total exercise time per week after 3 months. CONCLUSIONS We demonstrated that the RT-CGM was useful in modifying a patient's diet and exercise habits and could induce better glycemic control than SMBG for patients with type 2 diabetes.
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Park KW, Choi KM, Hong SP, Han GS, Yoo JY, Jin DI, Seol JG, Park CS. Production of transgenic recloned piglets harboring the human granulocyte-macrophage colony stimulating factor (hGM-CSF) gene from porcine fetal fibroblasts by nuclear transfer. Theriogenology 2008; 70:1431-8. [PMID: 18804273 DOI: 10.1016/j.theriogenology.2008.03.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2007] [Revised: 02/18/2008] [Accepted: 03/12/2008] [Indexed: 11/18/2022]
Abstract
We used nuclear transfer (NT) to develop transgenic female pigs harboring goat beta-casein promoter/human granulocyte-macrophage colony stimulating factor (hGM-CSF). The expression of hGM-CSF was specific to the mammary gland, and the glycosylation-derived size heterogeneity corresponded to that of the native human protein. Although various cell types have been used to generate cloned animals, little is currently known about the potential use of fibroblasts derived from a cloned fetus as donor cells for nuclear transfer. The developmental potential of porcine cloned fetal fibroblasts transfected with hGM-CSF was evaluated in the present study. Cloned fetal fibroblasts were isolated from a recipient following the transplantation of NT embryos. The cells were transfected with both hGM-CSF and the neomycin resistance gene in order to be used as donor cells for NT. Reconstructed embryos were implanted into six sows during estrus; two of the recipient sows delivered seven healthy female piglets with the hGM-CSF gene (confirmed with PCR and fluorescent in situ hybridization) and microsatellite analysis confirmed that the clones were genetically identical to the donor cells. The expression of hGM-CSF was strong in the mammary glands of a transgenic pig that died a few days prior to parturition (110 d after AI). These results demonstrated that somatic cells derived from a cloned fetus can be used to produce recloned and transgenic pigs.
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Chun JK, Lee TJ, Choi KM, Lee KH, Kim DS. Elevated anti-alpha-enolase antibody levels in Kawasaki disease. Scand J Rheumatol 2008; 37:48-52. [PMID: 18189195 DOI: 10.1080/03009740701607075] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVE By functioning as a heat-shock protein (HSP), alpha-enolase has an important role in the pathophysiology of multivariant vasculitis. Kawasaki disease (KD) is a type of vasculitis occurring primarily in children. The role of alpha-enolase in KD was assessed by measuring anti-alpha-enolase antibody (Ab) titres in patients with KD and the usefulness of anti-alpha-enolase Ab as a diagnostic tool in atypical KD patients was evaluated. METHODS Anti-alpha-enolase Ab titres were measured by using an enzyme-linked immunosorbent assay (ELISA) in seven normal control patients, nine febrile control patients and 14 KD patients (10 typical KD, four atypical KD). A standard deviation (SD) of 3 above the mean of the normal control group was considered to be positive reactivity. Western blotting using recombinant human alpha-enolase was performed in four KD patients and three normal controls. RESULTS With the positive reactivity limited to +3 SD over the mean (>0.6), 10 out of 14 patients (71%) were positive at the acute onset and 12 out of 14 patients (85.7%) were positive before discharge. In total, 12 out of 14 patients (85.7%) were positive either at acute onset or before discharge. All four atypical KD patients showed positive reactivity. Specific positive bands against recombinant human alpha-enolase were detected by western blotting in all four KD patients, but no reactivity was seen in three patients with normal controls. CONCLUSION This is the first study to demonstrate that autoantibodies against the alpha-enolase are present in the sera of KD patients. We suggest that anti-alpha-enolase Ab should be a good candidate for a diagnostic tool in atypical KD.
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Seo JA, Kim NH, Park SY, Kim HY, Ryu OH, Lee KW, Lee J, Kim DL, Choi KM, Baik SH, Choi DS, Kim SG. Serum retinol-binding protein 4 levels are elevated in non-alcoholic fatty liver disease. Clin Endocrinol (Oxf) 2008; 68:555-60. [PMID: 17941908 PMCID: PMC2344088 DOI: 10.1111/j.1365-2265.2007.03072.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Retinol-binding protein 4 (RBP4) is a recently identified adipokine that is elevated in the serum in several insulin-resistant states. We investigated the relationship between non-alcoholic fatty liver disease (NAFLD) and serum RBP4 in nondiabetic adults. METHODS One hundred and fifty-nine nondiabetic, non-alcoholic subjects (95 males and 64 females) participated in this study. Division of subjects into a NAFLD group (n = 73; 45 males and 28 females) or a normal group (n = 86; 50 males and 36 females) was based on the presence of fatty liver disease determined by sonography. RESULTS Serum RBP4 levels in the NAFLD group were significantly higher than those in the normal group (62.8 +/- 16.0 mg/l vs. 51.7 +/- 14.6 mg/l, P < 0.0001). Multiple logistic regression analysis revealed that the RBP4 level was an independent factor associated with NAFLD (P = 0.0042). In addition, serum RBP4 levels were positively correlated with serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltranspeptidase (GGT) levels. The significant association between serum RBP4 and GGT levels remained even after adjusting for age, gender, body mass index, the homeostasis model of assessment (HOMA) value and the presence of NAFLD (r = 0.3097, P = 0.0002). CONCLUSION Serum RBP4 levels are significantly associated with NAFLD and liver enzymes.
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Choi KM, Lee JS, Kim EJ, Baik SH, Seo HS, Choi DS, Oh DJ, Park CG. Implication of lipocalin-2 and visfatin levels in patients with coronary heart disease. Eur J Endocrinol 2008; 158:203-7. [PMID: 18230827 DOI: 10.1530/eje-07-0633] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVES Visfatin and lipocalin-2 are novel adipokines associated with insulin resistance (IR) and obesity-related metabolic disorders. We compared lipocalin-2 and visfatin concentrations between patients with coronary heart disease (CHD) and control subjects and evaluated their association with cardiovascular risk factors. METHODS We examined serum visfatin, lipocalin-2 levels, and cardiovascular risk factors in 91 subjects (49 patients with angiographically confirmed CHD versus 42 age- and gender-matched control participants). RESULTS Circulating lipocalin-2 levels were significantly higher in patients with CHD compared with the control subjects (82.6+/-38.7 ng/ml versus 43.8+/-27.8 ng/ml; P<0.001). However, visfatin levels were not significantly different between patients with CHD and control subjects. Serum lipocalin-2 levels were positively associated with weight (r=0.26; P=0.036), fasting insulin (r=0.36; P=0.003), and IR (r=0.33; P=0.007), whereas these levels showed a negative correlation with high-density lipoprotein (HDL) cholesterol (r=-0.30; P=0.016) after adjustment for gender and body mass index. However, visfatin levels were not associated with any variables of the metabolic syndrome. The multiple regression analysis showed that lipocalin-2 levels were independently associated with HDL cholesterol and IR (R2=0.199). Furthermore, the multiple logistic regression analysis showed that systolic blood pressure, IR, and lipocalin-2 levels were independently associated with CHD. CONCLUSIONS Serum lipocalin-2 levels were significantly elevated in patients with CHD and were independently associated with CHD. The present findings suggest that the measurement of serum lipocalin-2 levels may be useful for assessing CHD risk.
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Choi KM, Kim JH, Cho GJ, Baik SH, Park HS, Kim SM. Effect of exercise training on plasma visfatin and eotaxin levels. Eur J Endocrinol 2007; 157:437-42. [PMID: 17893257 DOI: 10.1530/eje-07-0127] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Visfatin, a novel adipokine, was revealed to be associated with obesity and to have insulin-mimetic effect. Eotaxin, which is an important chemokine in asthma, was recently reported to be associated with obesity in mice and humans. We evaluated the effect of exercise training on plasma visfatin and eotaxin levels in association with cardiovascular risk factors. DESIGN Forty-eight non-diabetic Korean women were evaluated before and after a 12 week exercise program including aerobic exercise (45 min/session, 300 Kcal/day) and muscle strength training (20 min/session, 100 Kcal/day) five times per week. RESULTS Plasma visfatin concentrations were elevated in obese subjects (body mass index, BMI> or =25 kg/m2) when compared with non-obese subjects (16.4 +/- 13.4 ng/ml vs 7.7 +/- 5.2 ng/ml, P = 0.006), and eotaxin concentrations were elevated in subjects with central obesity (waist circumference, WC> or =80 cm) when compared with those without central obesity (73.6 +/- 17.8 pg/ml vs 64.2 +/- 4.2 pg/ml, P = 0.005). In multiple regression analyses, visfatin levels were associated with BMI (R2 = 0.255) and eotaxin levels were associated with WC and body weight (R2 = 0.307). After the exercise program, body weight, blood pressure, fasting glucose, and insulin resistance of participants were decreased. Furthermore, plasma visfatin levels were significantly decreased from 13.6 +/- 12.0 to 7.7 +/- 7.9 ng/ml (P = 0.026) and eotaxin levels were reduced from 72.0 +/- 16.7 to 66.9 +/- 14.2 pg/ml (P = 0.018). CONCLUSIONS Exercise training with weight loss induced a significant reduction of plasma visfatin and eotaxin levels in non-diabetic Korean women.
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Choi KM, Shin KS, Yun SK, Ki MR, Hwang SY. Spectrophotometric determination of peptide transport with chromogenic peptide mimetics. Anal Biochem 2007; 367:167-72. [PMID: 17599798 DOI: 10.1016/j.ab.2007.05.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Revised: 05/11/2007] [Accepted: 05/22/2007] [Indexed: 10/23/2022]
Abstract
A spectrophotometric assay to determine peptide transport has been developed. Using two chromogenic peptide mimetics, L-phenylalanyl-L-2-sulfanilylglycine (PSG) and L-phenylalanyl-L-3-thiaphenylalanine (PSP), the peptide transport patterns in individual cell species can be evaluated effectively. After the addition of PSG to a HeLa cell suspension, sulfanilic acid accumulated progressively inside, but not outside, the cells, demonstrating that PSG was transported wholly intact. The addition of PSP to the same cell suspension was followed immediately by extracellular thiophenol production. Measurement of the rate of thiophenol release thereby provided direct determination of PSP transport. The thiophenol release was consistent with Michaelis-Menten kinetics, with a K(m) of 0.016 mM and a V(max) of 5.07 nmol/min (1 x 10(6) cells/ml, pH 7.4, 37 degrees C). The resulting kinetic constants estimated were in agreement with values determined by single-substrate enzyme kinetics. Using PSP, transport kinetics of various dipeptides was examined by competitive spectrophotometry. As a result, dipeptides tested could be ranked in order of kinetic power for their transport.
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Choi KM, Gibbons SJ, Roeder JL, Lurken MS, Zhu J, Wouters MM, Miller SM, Szurszewski JH, Farrugia G. Regulation of interstitial cells of Cajal in the mouse gastric body by neuronal nitric oxide. Neurogastroenterol Motil 2007; 19:585-95. [PMID: 17593140 DOI: 10.1111/j.1365-2982.2007.00936.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The factors underlying the survival and maintenance of interstitial cells of Cajal (ICC) are not well understood. Loss of ICC is often associated with loss of neuronal nitric oxide synthase (nNOS) in humans, suggesting a possible link. The aim of this study was to determine the effect of neuronal NO on ICC in the mouse gastric body. The volumes of ICC were determined in nNOS(-/-) and control mice in the gastric body and in organotypic cultures using immunohistochemistry, laser scanning confocal microscopy and three-dimensional reconstruction. ICC numbers were determined in primary cell cultures after treatment with an NO donor or an NOS inhibitor. The volumes of myenteric c-Kit-immunoreactive networks of ICC from nNOS(-/-) mice were significantly reduced compared with control mice. No significant differences in the volumes of c-Kit-positive ICC were observed in the longitudinal muscle layers. ICC volumes were either decreased or unaltered in the circular muscle layer after normalization for the volume of circular smooth muscle. The number of ICC was increased after incubation with S-nitroso-N-acetylpenicillamine and decreased by N(G)-nitro-l-arginine. Neuronally derived NO modulates ICC numbers and network volume in the mouse gastric body. NO appears to be a survival factor for ICC.
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72
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Choi KC, Lee SY, Yoo HJ, Ryu OH, Lee KW, Kim SM, Baik SH, Choi KM. Effect of PPAR-δ agonist on the expression of visfatin, adiponectin, and resistin in rat adipose tissue and 3T3-L1 adipocytes. Biochem Biophys Res Commun 2007; 357:62-7. [PMID: 17418807 DOI: 10.1016/j.bbrc.2007.03.114] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Accepted: 03/12/2007] [Indexed: 12/26/2022]
Abstract
It has been recently reported that activation of PPAR-delta, by specific agonists or genetic manipulation, alleviates dyslipidemia, hyperglycemia, and insulin resistance in animal models of obesity and type 2 diabetes. The purpose of the present study was to determine whether the PPAR-delta agonist has a direct effect on adipokines in visceral adipose tissue of rats and in cultured adipocytes. We examined the expression of visfatin, adiponectin, and resistin mRNA in visceral adipose tissue of Wistar rats fed a high-fat diet and 3T3-L1 adipocytes treated with PPAR-delta agonist (L-165041). Body weight and biochemical measurements were performed. Rats fed a high-fat diet showed a greater increase in body weight than those fed a standard diet (P<0.05), and treatment with L-165041 (10 mg/kg/day) significantly decreased weight gain (P<0.05). The concentration of total cholesterol was lower, and HDL cholesterol was higher in L-165041-treated rats (P<0.05). In the visceral adipose tissue of L-165041-treated rats, visfatin and adiponectin mRNA levels significantly increased compared to those of the untreated rats (P<0.05). However, the expression of resistin decreased in the L-165041-treated rats. Furthermore, in cultured 3T3-L1 adipocytes, the level of visfatin and adiponectin mRNA was up-regulated in response to L-165041 treatment for nine days. By contrast, resistin mRNA levels were down-regulated by L-165041 treatment. The present study provides a novel evidence to suggest that the PPAR-delta agonist has regulatory effects on a variety of adipokines, and these effects might explain some of their metabolic function.
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73
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Choi KM, Ryu OH, Lee KW, Kim HY, Seo JA, Kim SG, Kim NH, Choi DS, Baik SH. Serum adiponectin, interleukin-10 levels and inflammatory markers in the metabolic syndrome. Diabetes Res Clin Pract 2007; 75:235-40. [PMID: 16872712 DOI: 10.1016/j.diabres.2006.06.019] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Accepted: 06/19/2006] [Indexed: 10/24/2022]
Abstract
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.
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74
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Kim YM, Lee MH, Piao TG, Lee JW, Kim JH, Lee S, Choi KM, Jiang JH, Kim TU, Park H. Prodomain processing of recombinant plasmepsin II and IV, the aspartic proteases of Plasmodium falciparum, is auto- and trans-catalytic. J Biochem 2007; 139:189-95. [PMID: 16452306 DOI: 10.1093/jb/mvj018] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Prodomain processing of the four food vacuole plasmepsins (PMs), the malarial aspartic proteases, is prerequisite for their activity on hemoglobin degradation of the parasite Plasmodium falciparum. Although previous studies have suggested the involvement of a calpain-like PM convertase in the processing of PMs, the underlying mechanism of their processing remains to be clarified. Here, to investigate the mechanism by which food vacuole PM II and IV are processed, we used their wild-type and mutant proteins in which the catalytic Asp residue in two active-site motifs was mutated, as well as protease inhibitors. Autocatalytic processing of wild-type PM II and IV was inhibited only by an aspartic protease inhibitor pepstatin A. Unexpectedly, their proteolytic activities were inhibited not only by pepstatin A but also by calpain inhibitor ALLN. The active-site mutants of both PM II and IV showed neither autocatalytic processing nor proteolytic activities. However, the mutants of both PMs were efficiently processed upon incubation with their respective wild type proteins. Furthermore, the mutants of both PMs were processed upon incubation with each other's wild-type PM in both pepstatin A- and ALLN-sensitive manners. These results suggest that the processing of PM II and IV occurs via an intra- and inter-molecular autocatalytic event as well as via a transcatalytic event between them.
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75
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Park HS, Kim SM, Lee JS, Lee J, Han JH, Yoon DK, Baik SH, Choi DS, Choi KM. Prevalence and trends of metabolic syndrome in Korea: Korean National Health and Nutrition Survey 1998-2001. Diabetes Obes Metab 2007; 9:50-8. [PMID: 17199718 DOI: 10.1111/j.1463-1326.2005.00569.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
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.
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