Hyosoon Park

Relationship of serum osteoprotegerin levels with coronary artery disease severity, left ventricular hypertrophy and C-reactive protein.

OPG (osteoprotegerin) is an inhibitor of osteoclastogenesis and recent work suggests it has a role in atherosclerosis. Therefore we measured serum OPG levels in patients with coronary artery disease, compared the serum OPG levels among the different groups according to the number of stenotic vessels and determined whether there was any correlation with aortic calcification, LV (left ventricular) mass index and serum CRP (C-reactive protein) levels. Subjects (n=100; mean age, 57 years) who underwent coronary angiograms were enrolled. Blood pressure, body mass index, fasting blood glucose, lipid profiles and CRP levels were measured and the LV mass indices were calculated using ECGs. Serum OPG levels were measured by ELISA. The presence of calcification in the aortic notch was checked by a chest X-ray. The subjects were divided into four groups according to the number of stenotic vessels. The mean serum OPG levels increased significantly as the number of stenotic vessels increased, and the mean serum OPG levels were higher in the group with three-vessel disease compared with the groups with no- or one-vessel disease. The mean serum CRP level was significantly higher in the group with three-vessel disease compared with the groups with no-, one- and two-vessel disease. Age and LV mass index showed significant positive correlations with serum OPG levels, although significance was lost after an adjustment for age. Serum CRP levels were positively correlated with serum OPG levels even after an adjustment for age. There were no differences in serum OPG levels according to the presence of fasting hyperglycaemia or aortic calcification. In conclusion, serum OPG level was related to the severity of stenotic coronary arteries and serum CRP levels. LV mass indices showed no significant correlation with OPG levels. The precise mechanism for the role of OPG in atherosclerosis needs to be investigated further.

Dual-Priming Oligonucleotide-Based Multiplex PCR for the Detection of Helicobacter pylori and Determination of Clarithromycin Resistance with Gastric Biopsy Specimens

Background:  Assessment of Helicobacter pylori (H. pylori) clarithromycin resistance has rarely been performed routinely despite an increasing resistance rate. Our aim was to develop and evaluate the use of dual‐priming oligonucleotide (DPO)‐based multiplex polymerase chain reaction (PCR) to detect point mutations in the 23S rRNA gene responsible for clarithromycin resistance of H. pylori.

Effects of total cholesterol and triglyceride on the percentage difference between the low-density lipoprotein cholesterol concentration measured directly and calculated using the Friedewald formula.

Abstract Background: We elucidate how the triglyceride (TG) and total cholesterol (TC) concentrations affect the percentage difference (%ΔLDL) between the low-density lipoprotein cholesterol (LDL-C) concentration evaluated by direct measurement (DLDL-C) and calculated using the Friedewald formula (FLDL-C), under conditions allowing the calculation. Methods: Serum concentrations of TC, TG, high-density lipoprotein cholesterol (HDL-C), and DLDL-C were measured and the FLDL-C and %ΔLDL were calculated for 38,243 Koreans who had TG values <4.52 mmol/L. The DLDL-C was measured using the homogeneous Kyowa Medex assay (Kyowa, Tokyo, Japan). The %ΔLDL was calculated using the equation: [(FLDL-C–DLDL-C)/DLDL-C]×100. Results: The mean %ΔLDL-C was –9.1±6.4%. The %ΔLDL differed by more than ±5% in 75.4% of the subjects, and the FLDL-C was lower than the DLDL-C in 96.3%. The mean %ΔLDL-C for the group with the highest TG and lowest TC was 11.8-fold that for the group with the lowest TG and highest TC. Conclusions: Under conditions satisfying the requirements of the Friedewald formula, the DLDL-C and FLDL-C differed significantly over the concentration ranges of both TC and TG. In an evaluation of patients with hyperlipidemia, the Friedewald calculation may underestimate the risk for coronary heart disease. Clin Chem Lab Med 2008;46:371–5.

The effects of green tea ingestion over four weeks on atherosclerotic markers

Background: The objective of this study was to evaluate the effects of green tea ingestion over four weeks on atherosclerotic biological markers. Methods: After a one-week baseline period, 12 healthy male volunteers aged 28-42 years drank 600 mL of green tea dailyfor four weeks. Lipid profile, oxidized low-density lipoprotein (ox-LDL), total antioxidant capacity (TAC), C-reactive protein (CRP) and soluble cell adhesion molecules were measured at baseline and after two and four weeks ingestion of green tea. Results: There was no significantchange in the concentrations of lipid profile, TAC, CRP, soluble intercellular adhesion molecule-1 (sICAM-1), or soluble E-selectin after ingestion of green tea. The levels of ox-LDL and soluble vascular cell adhesion molecule-1 (sVCAM-1) were significantly decreased after four weeks of green tea ingestion (Wilcoxon signed rank test, P=0.006). Conclusions: The results of this study suggest an in vivo anti-oxidative effect for green tea and an influence of green tea on atherosclerotic biological markers. The effect of green tea seen on ox-LDL and sVCAM-1provides a potential mechanism for the cardiovascular benefits of regular ingestion of green tea.

Comparison of the Anyplex II HPV28 assay with the Hybrid Capture 2 assay for the detection of HPV infection.

BACKGROUND Human papillomavirus (HPV) testing is an important part of cervical cancer screening and management of women with abnormal cytology results. The Hybrid Capture 2 (HC2) has been recommended for use as a reference test. OBJECTIVE To evaluate a new real-time PCR assay (Anyplex II HPV28) for detecting high risk (HR) HPV and to compare it to the HC2. In addition, we compared the genotyping results of the Anyplex II HPV28 to those of sequencing analysis. STUDY DESIGN A total of 1114 cervical swab specimens were consecutively obtained from a single healthcare center. We submitted all specimens for HPV detection with Anyplex II HPV28 and HC2, then analyzed the discordant results using multiplex PCR followed by direct sequencing. RESULTS HC2 detected 72 (6.5%) cases with HR HPV, while Anyplex II HPV28 identified 138 (12.4%) cases. The overall agreement rate was 91.4% (1018/1114) of cases. Discordant results between these two assays were observed in 96 cases; 15 were positive only by HC2, and 81 were positive only by Anyplex II HPV28. Sequencing analyses performed in 80 cases of discordant results revealed 11 false-positive, and 67 false-negative results using HC2 tests and two false-positive results using Anyplex II HPV28. CONCLUSIONS The Anyplex II HPV28 assay is analytically more sensitive in the detection of the 13 HR types represented by the HC2 assay and exhibited a higher concordance with comprehensive genotyping based on the sequencing analysis, and it could be used as a laboratory testing method for identifying HPV genotypes.

1,5-Anhydroglucitol reflects postprandial hyperglycemia and a decreased insulinogenic index, even in subjects with prediabetes and well-controlled type 2 diabetes

To examine the serum 1,5-anhydroglucitol (AG) levels as a surrogate measure of postprandial hyperglycemia (PPH) and insulin secretion in a wide range of hyperglycemia, we compared the relationship between the glycemic index during a 75g oral glucose tolerance test (OGTT) and the insulinogenic index and 1,5-AG according the overall glycemic state. Fasting serum 1,5-AG levels were lower in the type 2 diabetic group (18.0+/-7.0microg/mL) than in the normal glucose tolerance (NGT, 25.4+/-4.0microg/mL), impaired fasting glucose (IFG, 24.6+/-6.2microg/mL), and impaired glucose tolerance (IGT, 22.1+/-6.2microg/mL) groups and were clearly correlated with glycemic values from the OGTT. 120-min post-challenge plasma glucose (PPG(120)) emerged as an independent predictor for 1,5-AG levels after multiple linear regression analysis (beta=-0.554, P<0.001). Additionally, 1,5-AG levels were significantly correlated with PPG(120) in each quartile of A1C, and the coefficients increased with higher A1C quartiles. Subjects with low 1,5-AG levels had both increased insulin resistance and decreased insulin secretion. Decreased 1,5-AG levels are closely correlated with PPH and decreased insulin secretion capacity across a wide range of glycemia, even in relatively well-controlled diabetes.

Serum 1,5-anhydroglucitol is associated with diabetic retinopathy in Type 2 diabetes

Diabet. Med. 29, 1184‐1190 (2012)

Molecular Cytogenetic Analysis of Gene Rearrangements in Childhood Acute Lymphoblastic Leukemia

The aims of this study were to estimate the incidences of BCR/ABL, MLL, TEL/AML1 rearrangements, and p16 deletions in childhood acute lymphoblastic leukemia (ALL), to identify new abnormalities, and to demonstrate the usefulness of interphase fluorescence in situ hybridization (FISH). We performed G-banding analysis and FISH using probes for BCR/ABL, MLL, TEL/AML1 rearrangements, and p16 deletions on 65 childhood ALL patients diagnosed and uniformly treated at a single hospital. Gene rearrangements were identified in 73.8% of the patients using the combination of G-banding and FISH, while the chromosomal abnormalities were identified in 49.2% using G-banding alone. Gene rearrangements were disclosed by FISH in 24 (72.7%) of 33 patients with normal karyotype or no mitotic cell in G-banding. Among the gene rearrangements detected by FISH, the most common gene rearrangement was p16 deletion (20.3%) and the incidences of others were 14.1% for TEL/AML1, 11.3% for MLL, and 1.8% for BCR/ABL translocations. Infrequent or new aberrations such as AML1 amplification, MLL deletion, ABL deletion, and TEL/AML1 fusion with AML1 deletion were also observed. We established the rough incidences of gene rearrangements in childhood ALL, found new abnormalities and demonstrated the diagnostic capability of interphase FISH to identify cryptic chromosome aberrations.

Higher Serum Direct Bilirubin Levels Were Associated with a Lower Risk of Incident Chronic Kidney Disease in Middle Aged Korean Men

Background The association between serum bilirubin levels and incident chronic kidney disease (CKD) in the general population is unknown. We aimed to examine the association between serum bilirubin concentration (total, direct, and indirect) and the risk of incident CKD. Methods and Findings Longitudinal cohort study of 12,823 Korean male workers 30 to 59 years old without CKD or proteinuria at baseline participating in medical health checkup program in a large worksite. Study participants were followed for incident CKD from 2002 through 2011. Estimated glomerular filtration rate (eGFR) was estimated by using the CKD-EPI equation. CKD was defined as eGFR <60 mL/min per 1.73 m2. Parametric Cox models and pooled logistic regression models were used to estimate adjusted hazard ratios for incident CKD. We observed 238 incident cases of CKD during 70,515.8 person-years of follow-up. In age-adjusted models, the hazard ratios for CKD comparing quartiles 2–4 vs. quartile 1 of serum direct bilirubin were 0.93 (95% CI 0.67–1.28), 0.88 (0.60–1.27) and 0.60 (0.42–0.88), respectively. In multivariable models, the adjusted hazard ratio for CKD comparing the highest to the lowest quartile of serum direct bilirubin levels was 0.60 (95% CI 0.41–0.87; P trend = 0.01). Neither serum total nor indirect bilirubin levels were significantly associated with the incidence of CKD. Conclusions Higher serum direct bilirubin levels were significantly associated with a lower risk of developing CKD, even adjusting for a variety of cardiometabolic parameters. Further research is needed to elucidate the mechanisms underlying this association and to establish the role of serum direct bilirubin as a marker for CKD risk.

Distribution of haptoglobin phenotypes in a Korean population, using the semi-automated PhastSystem

We have established a new phenotyping method for haptoglobin, based on sodium dodecyl sulphate-polyacrylamide gel electrophoresis using the PhastSystem (Pharmacia Biotech, Uppsala, Sweden), followed by immunoblotting for detection. We measured haptoglobin concentrations and determined the haptoglobin phenotypes of 316 healthy Koreans using this method: 31 (9·8%) were of Hp 1-1 type, 140 (44·3%) of Hp 2-1 type and 145 (45·9%) of Hp 2-2 type. The haptoglobin allele frequencies were calculated to be 0·32 for Hp 1 and 0·68 for Hp 2. We were able to visualize up to 12 bands from the human Hp 2-2 polymeric series, with molecular weights in the range 171·9 x 103 to 802·2 x 103. The reference range of serum haptoglobin concentrations obtained by the IFCC (International Federation of Clinical Chemistry) standard method was 0·27 - 2·14 g/L. The serum haptoglobin concentration in Koreans was similar to that of Caucasians, but the Hp1 allele frequency was lower in Koreans. Our method could be used in clinical laboratories as a simple and practical method of haptoglobin phenotyping. In addition, the Hp 2-2 polymeric series could be used as high molecular weight standards.