Clinical Research Coordinating Center

Seoul, South Korea

Clinical Research Coordinating Center

Seoul, South Korea
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Kwak J.,Catholic Medical Center | Jeong H.,Catholic University of Korea | Chun S.,Catholic University of Korea | Bahk J.H.,Catholic Medical Center | And 5 more authors.
BMJ Open | Year: 2017

Objectives Since the Health Promotion Act was introduced in Korea in 1995, anti-smoking policies and regulations have undergone numerous revisions, and non-smoking areas have gradually been expanded. The purpose of this study was to examine the impact of a partial legislative ban on adolescent exposure to secondhand smoke using objective urinary cotinine levels in a nationwide representative sample. Methods Urine cotinine levels were measured in the Korea National Health and Nutrition Examination Survey from 2008 to 2011. This study was a trend analysis of 4 years of national survey data from 2197 Korean youth aged 10-18 years. Among non-smokers, the 75th percentile urinary cotinine level was estimated. We also considered the number of household smokers. Results The 75th percentile urine cotinine level of non-smokers showed a significant decreasing trend from 2008 to 2011, from 15.47 to 5.37 ng/mL, respectively. Urine cotinine did not decline significantly in non-smokers living with smokers during the study period. The results did not show a statistically significant reduction in smoking rate in adolescents from 2008 to 2011, although there was a trend towards a decrease (p=0.081). Conclusions Based on urine cotinine levels, government-initiated anti-smoking policies have only been effective among highly exposed non-smoking adolescents during the study period. Further study needs to evaluate whether or not the legislative ban affects domestic smoking exposure. © Article author(s) 2017.

Jeong H.,Catholic University of Korea | Yim H.W.,Catholic University of Korea | Yim H.W.,Clinical Research Coordinating Center | Cho Y.-S.,Seo myeon Branch Office of the Community Health Center | And 4 more authors.
International Journal of Stem Cells | Year: 2014

Background and Objectives: Stem cell-based therapy is a potential new approach in the treatment of stroke. However, the efficacy and safety of these treatments are not yet fully understood. Therefore, we performed a meta-analysis of available single-arm studies using stem cell-based therapy in patients with stroke. Methods: We searched MEDLINE, EMBASE, and the Cochrane database for studies of stem cell therapy in patients with stroke from its inception through July 2014. The articles included in the search were restricted to the English language, studies with at least 5 patients, and those using cell-based therapies for treating stroke. Results: Fourteen studies included in the meta-analysis. The pooled mean difference in National Institutes of Health Stroke Scale (NIHSS) scores from baseline to follow-up points was 5.7 points (95%CI: -8.2 to -3.2, I2=91.5%) decreased. Also the pooled mean difference in modified Bathel index (BI) score was increased by 31.5 points (95%CI: 35.6~14.9, I2=52.7%) and the pooled incidence rate to achieve on modified Rankin score (mRS)≤2 was 40% (95% CI: 30%~51%, I2=35.4%) at follow-up points. The pooled incidence rates of death, seizure, and infection were 13% (95%CI, 8~23%), 15% (95%CI, 8~25%), and 15% (95%CI, 8~23%), respectively. Conclusions: The published data suggest that stem cell-based therapy for patients with stroke can be judged as effective based on single arm clinical studies. However, clinical benefits of stem cell therapy for patients with stroke need further investigation and reevaluation to test the clinical efficacy.

Jeong H.,Catholic University of Korea | Yim H.W.,Catholic University of Korea | Cho Y.,Occupational and Environmental Medicine | Park H.J.,Seoul St Marys Hospital | And 4 more authors.
Stem Cell Research and Therapy | Year: 2013

Introduction. Although blinding is a methodologic safeguard to ensure obtaining comparability of groups in a clinical trial, it is very difficult to maintain blinding from the beginning to the end of a study. The aim of the study was to see how proper blinding of both participants and treatment providers from the planning phase of the study to during the study affected the study outcomes. Methods. We searched Medline, EMBASE, and Cochrane databases from inception to November 2011. The studies included in this review were randomized controlled trials, with acute myocardial infarction (AMI) patients who received percutaneous coronary intervention (PCI), intracoronary (IC) infusion of autologous bone marrow stem cells (BMSCs), unselected BMSCs, 108 or more cell dose, and up to 6-month follow-up periods. Results: The initial search identified 881 references, of which 17 references were eligible for inclusion. Six of 17 trials isolated cells directly from bone marrow by aspiration in the control group as well as in the BMSC group. Nine of 17 trials underwent both cardiac catheterization and an identical injection procedure on the control group as well as the BMSC group.Compared with the control group, BMSC transplantation improved left ventricular ejection fraction (LVEF) by 2.51 (95% CI, 1.20 to 3.83; P = 0.0002; I 2 = 75%) at 6 months. In the present results, the studies that did not perform bone marrow aspiration in the control group showed significant improvement in LVEF by 3.81% (95% CI, 2.44 to 5.17), whereas no significant treatment effect was found in the studies in which the control group underwent bone marrow aspiration, as indicated the LVEF change of -1.29% (95% CI, 4.15 to 1.58). The trials that did not conduct catheterization on control subjects showed significant LVEF changes (4.45%; 95% CI, 2.48 to 6.43); however, those with cardiac catheterization as a sham procedure on the control group did not show significant changes in LVEF at 6 months (0.92%; 95% CI, -0.61 to 2.44). Conclusions: Unblinding might be overestimating the treatment effect. These findings suggest that randomized controlled trials testing the efficacy of BMSC therapy should be appropriately designed and rigorously applied to avoid bias. © 2013 Jeong et al.; licensee BioMed Central Ltd.

Cha K.-H.,Catholic University of Korea | Sim Y.B.,Catholic University of Korea | Chae H.,Catholic University of Korea | Chae H.,Clinical Research Coordinating Center | And 6 more authors.
Journal of Clinical Laboratory Analysis | Year: 2014

Background: SPAPLUS™ is a turbidimetric immunoassay analyzer for detection of excess free light chain (FLC) antigens in serum. Here, we evaluated the analytical performance of Freelite™ Human Kappa Free and Lambda Free on a SPAPLUS™ instrument. Methods: We evaluated the precision, linearity, sample carryover, and drift of the SPAPLUS™ instrument and compared it with Hitachi 7600 and BN™ II instruments. We evaluated the detection of antigen excess for 12 specimens from patients with monoclonal gammopathy. Results: The coefficients of variations of κFLC and λFLC were below 5.0%. Linearity was shown in the range of 9.68-152.25 mg/l for κFLC and 4.96-171.09 mg/l for λFLC, and no drift was observed. The κFLC sample carryover was statistically significant, but much smaller than the optimum allowable bias. Agreement rates with the two comparative methods were 87.1, 87.1, and 97.1% or higher for κFLC, λFLC, and the κ/λ ratio, respectively. Antigen excess signals were observed for all 12 antigen excess specimens. Conclusions: The Freelite™ on the SPAPLUS™ exhibited appropriate precision, linearity, and relative comparability to the reagents on the other instruments. It was good at detecting specimens that had previously demonstrated the hook effect due to antigen excess. © 2014 Wiley Periodicals, Inc.

Gu N.,Seoul National University | Kim B.-H.,Seoul National University | Chung Y.-J.,Seoul National University | Lim K.-S.,Seoul National University | And 5 more authors.
Journal of Korean Society for Clinical Pharmacology and Therapeutics | Year: 2011

Background: Both aspirin and simvastatin are prescribed as treatments or prevention of cardiovascular diseases. The aim of this study was to investigate the influence of simvastatin on pharmacokinetics and pharmacodynamics of aspirin after oral co-administration in healthy subjects. Methods: Subjects were orally administered aspirin 100 mg for 7 days followed by co-administration of aspirin 100 mg and simvastatin 40 mg for 7 days once daily. A series of blood samples were collected before and till 24hours after drug administration on Day 1 (single-dose of aspirin), Day 7 (multiple-dose of aspirin) and Day 14 (multiple-dose of aspirin and simvastatin). The effects of simvastatin on pharmacokinetics of acetylsalicylic acid and salicylic acid were assessed with the 90 % confidence intervals (CIs) of thegeometric mean ratios (GMRs) of Day 14 over Day 7 for maximum plasma concentration (C max) and the area under the concentration-time curve (AUC 0-24). Pharmacodynamics was assessed with maximal changes of platelet aggregation from baseline. Results: Twenty-fourhealthy men aged 20 to 36 years were enrolled and 23 of them completed the study. GMRs (90 % CIs) of C max and AUC 0-24 for acetylsalicylic acid were 1.21 (1.04 - 1.42) and 1.28 (1.19 - 1.38), respectively. For salicylic acid, GMRs of C max and AUC 0-24 were 0.96 (0.91 - 1.00) and 1.00 (0.97 - 1.04), respectively. Maximal changes of platelet aggregation on Day 7 and Day 14 from baseline were not significantly different (p=0.41); 87.5 ± 8.8 % and 87.3 ± 9.2 %, respectively. Conclusion: Coadministration of simvastatin slightly increased the systemic exposure of acetylsalicylic acid with no changes of systemic exposure of salicylic acid or inhibition of platelet aggregation.

Oh S.J.,Catholic University of Korea | Lee J.I.,Catholic University of Korea | Ha W.C.,Catholic University of Korea | Jeong S.H.,Clinical Research Coordinating Center | And 4 more authors.
Diabetic Medicine | Year: 2012

Aims The influence of hyperglycaemia on the performance of glomerular filtration rate (GFR) estimating equations remains to be determined. We compared the performance of creatinine-based GFR with cystatinC-based GFR in patients with Type2 diabetes according to glycaemic status. Methods In a cross-sectional study of 210 patients with Type2 diabetes, we staged glycaemic status by HbA 1c tertiles [HbA 1c≤75mmol/mol (9.0%) (n=70), HbA 1c 76-95mmol/mol (9.1-10.8%) (n=70), HbA 1c >95mmol/mol (10.8%) (n=70)] and measured GFR. Isotopic GFR was measured using renal dynamic imaging with 99mTc-diethylene-triamine-penta-acetic acid. Estimated GFR (eGFR) was measured using creatinine-based formulae (Cockcroft-Gault-eGFR, the Modification of Diet in Renal Disease equation-eGFR and the Chronic Kidney Disease Epidemiology Collaboration formula-eGFR) and a cystatinC-based formula (cystatinC-eGFR). Results The isotopic GFR of all patients was 93.1±34.1mlmin -11.73m -2. All methods for estimating GFR underestimated isotopic GFR [Cockcroft-Gault-eGFR (68.8±38.6mlmin -11.73m -2) (P<0.05), Modification of Diet in Renal Disease-eGFR (74.8±31.3mlmin -11.73m -2) (P<0.05), Chronic Kidney Disease Epidemiology Collaboration-eGFR (72.9±26.6mlmin -11.73m -2) (P<0.05) and cystatinC-eGFR (83.5±33.2mlmin -11.73m -2) (P<0.05)]. In all patient groups, cystatinC-eGFR was less biased and more accurate than the creatinine-based formulae, especially in the group with HbA 1c >95mmol/mol (10.8%) where there was no difference between cystatinC-eGFR and isotopic GFR. Conclusions Performance of cystatinC-eGFR was superior to creatinine-based GFR in patients with Type2 diabetes with HbA 1c >95mmol/mol (10.8%). © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.

Park H.-I.,Catholic University of Korea | Park H.-I.,Clinical Research Coordinating Center | Chae H.,Catholic University of Korea | Chae H.,Clinical Research Coordinating Center | And 6 more authors.
Journal of Clinical Laboratory Analysis | Year: 2014

Background: We developed a two-dimensional plot for viewing trueness that takes into account potential shift and variable quality requirements to verify trueness using certified reference material (CRM). Methods: Glucose, total cholesterol (TC), and creatinine levels were determined by two kinds of assay in two levels of a CRM. Available quality requirements were collected, codified, and sorted in an ascending order in the plot's header row. Centering on the mean of measured values from CRM, the "mean ± US CLIA '88 allowable total error" was located in the header of the leftmost and rightmost columns. Twenty points were created in intervening columns as potential shifts. Uncertainties were calculated according to regression between certified values and uncertainties of CRM, and positioned in the corresponding columns. Cells were assigned different colors where column and row intersected based on comparison of the 95% confidence interval of the percentage bias with each quality requirement. Results: A glucose assay failed to meet the highest quality criteria, for which shift of +0.13-0.14 mmol/l was required. A TC assay met the quality requirement and a shift of ±0.03 mmol/l was tolerable. A creatinine assay also met the quality requirement but any shift was not tolerable. Conclusion: The plot provides a systematic view of the trueness of quantitative laboratory tests. © 2014 Wiley Periodicals, Inc.

Kwon S.-K.,Chung - Ang University | Kwon S.-K.,Clinical Research Coordinating Center | Yang Y.-J.,Chung - Ang University | Chun Y.-J.,Chung - Ang University | Hong Y.-P.,Chung - Ang University
Toxicological and Environmental Chemistry | Year: 2010

This study was performed to investigate the adverse effects of bisphenol A diglycidyl ether (BADGE) on rat epididymis. BADGE was administered orally to pregnant 8-week-old specific-pathogen-free (SPF) Sprague-Dawley female rats from gestational day 6 to lactation once daily at doses of 0 (control), 50, 200, or 400 mg kg-1 day-1. Five male pups in control and three treatment groups were culled and sacrificed by ether on postnatal days (PND) 21, 42, or 56. Body and epididymis changes in weight and developmental characteristics of each male pup were recorded. The pattern of expression of clusterin mRNA in the cauda epididymis was observed using real-time PCR. The level of expression of clusterin proteins was confirmed using Western blot analysis. Body weight of the treated group did not differ markedly from the control. The adjusted anogenital distance (AGD) (in mm kg-(1/3)) on PND 7 in the 50 mg kg-1 day-1 group was significantly shorter than control; however, on PND 14 in the 200 mg kg-1 day-1 group and on PND 4 and 14 in the 400 mg kg-1 day-1 group, AGD was significantly longer. The expression of clusterin mRNA was significantly decreased on PND 56 in the 200 mg kg-1 day-1 and on PND 42 and 56 in the 400 mg kg-1 day-1 groups. The trend in the level of expression of clusterin proteins was similar to expression of mRNA. Male rats treated with 50 mg kg-1 day-1 of BADGE exerted no effect on epididymis. Data suggests that down-regulation of clusterin expression may be involved in reproductive toxicity produced by BADGE on rat epididymis. © 2010 Taylor & Francis.

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