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1.  Lamotrigine-induced toxic epidermal necrolysis confirmed by in vitro granulysin and cytokine assays 
Asia Pacific Allergy  2014;4(4):253-256.
Lamotrigine is a recent medication which is prescribed for various neuropsychiatric conditions. It is generally well-tolerated, but recent pharmacoepidemiological evidence suggests that lamotrigine is associated with risks of developing severe cutaneous drug reactions like toxic epidermal necrolysis (TEN). However, there still remains the diagnostic challenge regarding how to confirm the drug causality in suspected cases. In most cases so far, lamotrigine causality has not been objectively demonstrated, which was possibly due to high risk of oral challenge tests or the lack of useful in vitro drug assays. Here we report a case of lamotrigine-induced TEN, of which the drug causality was confirmed by in vitro granulysin and cytokine assays.
PMCID: PMC4215432  PMID: 25379485
Toxic epidermal necrolysis; Lamotrigine; Granulysin; Natural killer cells; Cyclosporine
2.  Distribution of Abdominal Obesity and Fitness Level in Overweight and Obese Korean Adults 
Background. Abdominal obesity and its relative distribution are known to differ in association with metabolic characteristics and cardiorespiratory fitness. This study aimed to determine an association between fitness level and abdominal adiposity in overweight and obese adults. Methods. 228 overweight and obese individuals were classified as either cardiorespiratory unfit or fit based on their recovery heart rate. Visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), the visceral-to-subcutaneous adipose tissue ratio (VAT/SAT ratio), and cardiometabolic characteristics were analyzed to examine the relationship between recovery heart rate and abdominal adiposity components. Results. After adjustments for age and sex, significant relationships of recovery heart rate and VAT, SAT, and VAT/SAT ratio were found; however, SAT was not significantly associated after further adjustment for body mass index (BMI) (r = 0.045, P = 0.499), whereas VAT (r = 0.232, P < 0.001) and VAT/SAT ratio (r = 0.214, P = 0.001) remained associated. Through stepwise multiple regression analyses after adjustment for age, sex, BMI, lifestyle factors, mean blood pressure, fasting glucose, HOMA-IR, lipid profiles, and hsCRP, recovery heart rate was identified as an independent variable associated with VAT (β = 0.204, P < 0.001) and VAT/SAT ratio (β = 0.163, P = 0.008) but not with SAT (β = 0.097, P = 0.111). Conclusions. Cardiorespiratory fitness level is independently associated with VAT and the VAT/SAT ratio but not with SAT in overweight and obese adults.
PMCID: PMC3958687  PMID: 24723950
3.  Mitochondrial DNA Copy Number in Peripheral Blood Is Independently Associated with Visceral Fat Accumulation in Healthy Young Adults 
Aims. Visceral obesity is associated with an increased risk of cardiometabolic diseases and it is important to identify the underlying mechanisms. There is growing evidence that mitochondrial dysfunction is associated with metabolic disturbances related to visceral obesity. In addition, maintaining mitochondrial DNA (mtDNA) copy number is important for preserving mitochondrial function. Therefore, we investigated the relationship between mtDNA copy number and visceral fat in healthy young adults. Methods. A total of 94 healthy young subjects were studied. Biomarkers of metabolic risk factors were assessed along with body composition by computed tomography. mtDNA copy number was measured in peripheral leukocytes using real-time polymerase chain reaction (PCR) methods. Results. The mtDNA copy number correlated with BMI (r = −0.22, P = 0.04), waist circumference (r = −0.23, P = 0.03), visceral fat area (r = −0.28, P = -0.01), HDL-cholesterol levels (r = 0.25, P = 0.02), and hs-CRP (r = 0.32, P = 0.02) after adjusting for age and sex. Both stepwise and nonstepwise multiple regression analyses confirmed that visceral fat area was independently associated with mtDNA copy number (β = -0.33, P < 0.01, β = 0.32, and P = 0.03, resp.). Conclusions. An independent association between mtDNA content and visceral adiposity was identified. These data suggest that mtDNA copy number is a potential predictive marker for metabolic disturbances. Further studies are required to understand the causality and clinical significance of our findings.
PMCID: PMC3953665  PMID: 24707289
4.  Isolated Left Ventricular Apical Hypoplasia with Infundibular Pulmonary and Aortic Stenosis: a Rare Combination 
Korean Journal of Radiology  2013;14(6):874-877.
Isolated left ventricular (LV) apical hypoplasia is a rare congenital cardiac anomaly which is not accompanied by other cardiac abnormalities, with the exception of two cases. We report a case of a 33-year-old male patient with isolated LV apical hypoplasia combined with infundibular pulmonary stenosis and aortic stenosis. We review a literature focusing on the characteristic magnetic resonance features and combined cardiac abnormalities.
PMCID: PMC3835633  PMID: 24265561
Isolated left ventricular apical hypoplasia; Pulmonary subvascular stenosis; Aortic valve stenosis; Magnetic resonance imaging; Congenital heart disease
5.  Nonalcoholic fatty liver disease is associated with coronary artery disease in Koreans 
AIM: To investigate whether nonalcoholic fatty liver disease (NAFLD) affects coronary artery disease (CAD) and identify candidate mediators.
METHODS: Patients who underwent coronary angiography were consecutively recruited. The patients were classified into four groups by coronary artery stenosis: A, insignificant; B, one-vessel disease; C, two-vessel disease; and D, three-vessel disease. Abdominal ultrasonography was performed to determine the presence of a fatty liver and categorize by grade: 0, no evidence; 1, mild; 2, moderate; and 3, severe. We measured not only known CAD risk factors, but also serum insulin, HOMA-index, adiponectin, interleukin-6, tumor necrosis factor-α and high-sensitivity C-reactive protein levels.
RESULTS: Of the 134 patients who met the inclusion criteria, 82 (61.2%) had ultrasonographically diagnosed NAFLD. Among the 46 patients with CAD, 37 (80.4%) had evidence of a fatty liver. The two groups (A vs B-D) were significantly different in terms of age, total cholesterol, triglycerides, low-density lipoprotein levels and fatty liver. Coronary artery stenosis was strongly associated with fatty liver in a grade-dependent manner (P = 0.025). In binary logistic regression, NAFLD was a significant independent predictor of CAD (P = 0.03, OR = 1.685; 95%CI: 1.051-2.702). Among the candidate mediators, the serum adiponectin level showed a trend toward lowering based on CAD progression (P = 0.071).
CONCLUSION: NAFLD is an independent risk factor for CAD in a grade-dependent manner. Moreover, adiponectin might be related to the pathogenesis of NAFLD.
PMCID: PMC3801316  PMID: 24151364
Nonalcoholic fatty liver disease; Coronary artery disease; Coronary angiography; Adiponectin; Insulin resistance
6.  Serum Ferritin Is Differentially Associated with Anti-oxidative Status and Insulin Resistance in Healthy Obese and Non-obese Women 
Korean Journal of Family Medicine  2012;33(4):205-210.
Ferritin is known to be associated with insulin resistance (IR) and oxidative stress; however, recent studies have shown that there is an association between ferritin and anti-oxidative status. To date, the biphasic response of ferritin to oxidative stress has not been fully evaluated. Thus, we investigated the association between ferritin and IR and anti-oxidative status in obese and non-obese women.
We evaluated the homeostasis model assessment of insulin resistance (HOMA-IR) and total anti-oxidant status (TAS) in a total of 111 healthy women between the ages of 32 and 68 years.
In all of the study subjects, ferritin levels were positively correlated with age (r = 0.38, P < 0.001), body mass index (r = 0.24, P = 0.01), TAS (r = 0.38, P < 0.001) and HOMA-IR (r = 0.20, P = 0.04). In the subgroup analysis, ferritin levels were correlated with age (r = 0.39, P < 0.001) and TAS (r = 0.43, P < 0.001) in the non-obese group and with insulin (r = 0.50, P = 0.02) and HOMA-IR (r = 0.52, P = 0.01) levels in the obese group. On stepwise multiple linear regression analysis, ferritin was found to be independently associated with TAS (B = 177.16, P < 0.0001) in the non-obese group and independently associated with HOMA-IR (B = 30.36, P = 0.01) in the obese group.
Our findings suggest ferritin is associated with IR in obese women and with anti-oxidative status in non-obese women. Further studies are warranted to elucidate the precise role of ferritin in obesity.
PMCID: PMC3418339  PMID: 22916322
Ferritins; Obesity; Oxidative Stress
7.  Adiponectin in Women with Polycystic Ovary Syndrome 
Korean Journal of Family Medicine  2011;32(4):243-248.
Though adiponectin has been associated with insulin resistance and cardiovascular risk factors, the relationship between adiponectin and polycystic ovary syndrome (PCOS) remains controversial. The aim of this study was to compare adiponectin level in women with PCOS and without PCOS, and to investigate the relationship between adiponectin level and metabolic variables including insulin resistance.
60 women with PCOS were enrolled along with a control group of 80 healthy women, matched for age and body mass index (BMI). We measured hormonal and metabolic parameters, as well as the plasma adiponectin concentration of each participant. We estimated the insulin sensitivity according to the quantitative insulin sensitivity check index (QUICKI).
The PCOS group displayed significantly lower level of adiponectin (P < 0.001) after adjustment for age, BMI, mean blood pressure, fasting glucose, fasting insulin, and several metabolic parameters. Adiponectin levels were positively correlated with QUICKI in the PCOS group (P < 0.001) and the control group (P = 0.03). Following step-wise multiple regression analysis, however, adiponectin level was positively correlated with QUICKI in the control group only (P = 0.03). In addition, adiponectin level was found to be independently associated with HDL-cholesterol level (P < 0.001) and BMI (P = 0.02) in the PCOS group and independently associated with HDL-cholesterol (P = 0.02) in the control group.
We report decreased adiponectin level in PCOS patients in relation to controls independently of insulin resistance or other metabolic factors. And adiponectin is associated with both lipid metabolism and obesity, which, in turn, is related to insulin resistance in PCOS. Further studies are needed to clarify the mechanism of adiponectin in PCOS.
PMCID: PMC3383132  PMID: 22745860
Adiponectin; Polycystic Ovary Syndrome; Insulin Resistance
8.  Clinical Predictors of Novel Influenza A (H1N1) Infection in Korea 
Yonsei Medical Journal  2010;51(6):895-900.
Pandemic influenza A (H1N1) virus has spread rapidly and prompt diagnosis is needed for successful treatment and prevention of transmission. We investigated clinical predictors, validated the use of previous criteria with laboratory tests, and evaluated the clinical criteria for H1N1 infection in the Korean population.
Materials and Methods
We analyzed clinical and laboratory evaluation data from outpatient clinics at Severance Hospital in Seoul, Korea between November 11 and December 5, 2009.
This analysis included a total of 828 patients. Of these, 372 (44.9%) patients were confirmed with H1N1 infection by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). The most common and predictive symptom was cough (90.3%, OR 8.87, 95% CI 5.89-13.38) and about 40% of H1N1-positive patients were afebrile. The best predictive model of H1N1 infection was cough plus fever or myalgia. The sensitivities, specificities, positive predictive values, and negative predictive values of our suggested criteria were 73.9%, 69.5%, 66.4%, and 76.6%, respectively.
Cough was the most common independent symptom in patients with laboratory-confirmed H1N1 infection, and while not perfect, the combination of cough plus fever or myalgia is suggested as clinical diagnostic criteria. Health care providers in Korea should suspect a cough without fever to be an early symptom of H1N1 infection.
PMCID: PMC2995982  PMID: 20879057
Influenza A virus (H1N1 subtype); criteria; diagnosis
9.  Mimulone-Induced Autophagy through p53-Mediated AMPK/mTOR Pathway Increases Caspase-Mediated Apoptotic Cell Death in A549 Human Lung Cancer Cells 
PLoS ONE  2014;9(12):e114607.
Anticancer properties and mechanisms of mimulone (MML), C-geranylflavonoid isolated from the Paulownia tomentosa fruits, were firstly elucidated in this study. MML prevented cell proliferation in a dose- and time-dependent way and triggered apoptosis through the extrinsic pathway in A549 human lung adenocarcinoma cells. Furthermore, MML-treated cells displayed autophagic features, such as the formation of autophagic vacuoles, a primary morphological feature of autophagy, and the accumulation of microtubule-associated protein 1 light chain 3 (LC3) puncta, another typical maker of autophagy, as determined by FITC-conjugated immunostaining and monodansylcadaverine (MDC) staining, respectively. The expression levels of LC3-I and LC3-II, specific markers of autophagy, were also augmented by MML treatment. Autophagy inhibition by 3-methyladenine (3-MA), pharmacological autophagy inhibitor, and shRNA knockdown of Beclin-1 reduced apoptotic cell death induced by MML. Autophagic flux was not significantly affected by MML treatment and lysosomal inhibitor, chloroquine (CQ) suppressed MML-induced autophagy and apoptosis. MML-induced autophagy was promoted by decreases in p53 and p-mTOR levels and increase of p-AMPK. Moreover, inhibition of p53 transactivation by pifithrin-α (PFT-α) and knockdown of p53 enhanced induction of autophagy and finally promoted apoptotic cell death. Overall, the results demonstrate that autophagy contributes to the cytotoxicity of MML in cancer cells harboring wild-type p53. This study strongly suggests that MML is a potential candidate for an anticancer agent targeting both autophagy and apoptotic cell death in human lung cancer. Moreover, co-treatment of MML and p53 inhibitor would be more effective in human lung cancer therapy.
PMCID: PMC4260910  PMID: 25490748
10.  Visceral Fat Accumulation Is Associated with Colorectal Cancer in Postmenopausal Women 
PLoS ONE  2014;9(11):e110587.
Obesity is a known risk factor for colorectal cancer (CRC), and emerging data suggest that this association is mediated by visceral fat rather than total body fat. However, there is a lack of studies evaluating the association between visceral fat area and the prevalence of CRC.
To investigate the relationship between visceral adiposity and prevalence of CRC, data of 497 women diagnosed with CRC and 318 apparently healthy women were analysed and data of well-balanced 191 pairs of women with CRC and healthy women matched based on propensity scores were additionally analysed. Diagnosis of CRC was confirmed by colonoscopy and histology. Metabolic parameters were assessed, along with body composition, using computed tomography.
The median visceral fat area was significantly higher in the CRC group compared with the control group before and after matching. The prevalence of CRC increased significantly with increasing visceral fat tertiles after matching (p for trend <0.01). A multivariate analysis showed that mean visceral fat area of individuals in the 67th percentile or greater group was associated with an increased prevalence of CRC (adjusted odds ratio: 1.80; 95% confidence interval: 1.12–2.91 before matching and adjusted odds ratio: 2.96; 95% confidence interval: 1.38–6.33) compared with that of individuals in the 33th percentile or lower group.
Thus, we conclude that visceral fat area is positively associated with the prevalence of CRC. Although we could not determine the causality, visceral adiposity may be associated with the risk of CRC. Further prospective studies are required to determine the benefits of controlling visceral obesity for reducing CRC risk.
PMCID: PMC4234311  PMID: 25402501
11.  Clinical Outcome of Relapsed or Refractory Burkitt Lymphoma and Mature B-Cell Lymphoblastic Leukemia in Children and Adolescents 
Despite the rapid improvement in survival rate from Burkitt lymphoma and mature B-cell lymphoblastic leukemia (B-ALL) in children, a small subset of patients do not respond to first-line chemotherapy or experience relapse (RL). Herein, we report the clinical characteristics and outcomes of these patients.
Materials and Methods
RL or refractory Burkitt lymphoma and mature B-ALL in 125 patients diagnosed from 1990 to 2009 were retrospectively analyzed.
Nineteen patients experienced RL or progressive disease (PD). Among them, 12 patients had PD or RL less than six months after initial treatment and seven had late RL. Seven patients achieved complete response (CR), 11 had PD, and one had no more therapy. Six patients who achieved CR survived without evidence of disease and four of them underwent high-dose chemotherapy (HDC) followed by stem cell transplantation (SCT). However, 11 patients who failed to obtain CR eventually died of their disease. Five-year overall survival (OS) was 31.6±10.7%. OS of patients with late RL was superior to that of patients with early RL (57.1±18.7%, vs. 16.7±10.8%, p=0.014). Achievement of CR after reinduction had significant OS (p < 0.001). OS for patients who were transplanted was superior (p < 0.01). In multivariate analysis, achievement of CR after reinduction chemotherapy showed an association with improved OS (p=0.05).
Late RL and chemotherapy-sensitive patients have the chance to achieve continuous CR using HDC/SCT, whereas patients who are refractory to retrieval therapy have poor prognosis. Therefore, novel salvage strategy is required for improvement of survival for this small set of patients.
PMCID: PMC4206068  PMID: 25043820
Burkitt lymphoma; Recurrence; Children
13.  Aortic Unfolding Determined Using Non-Contrast Cardiac Computed Tomography: Correlations with Age and Coronary Artery Calcium Score 
PLoS ONE  2014;9(4):e95887.
Aortic unfolding occurs with aging and reflects proximal aortic dilation, aortic arch widening, and decreased curvature. This study 1) evaluated the relationship between aortic unfolding measured using non-contrast cardiac-gated computed tomography (CT) and age, 2) assessed factors influencing aortic unfolding, and 3) determined the association of this measurement with coronary artery calcium (CAC) score.
We reviewed the charts of 219 subjects (142 men, 77 women; mean age 54.2±9.3 years) who underwent coronary artery calcium scanning during routine health screening from December 2010 to May 2011. Multivariate regression analysis according to cardiovascular risk factors was performed. We also analyzed the relationship between aortic unfolding measurements and CAC score using stepwise multiple linear regression.
Mean aortic unfolding was 103.7±13.9 mm (men, 106.5±13.5 mm; women, 98.4±12.9 mm). Age, body surface area, and hypertension were exclusively associated with aortic unfolding. The association between aortic unfolding and CAC score was significant after adjustment for age and gender (β = 1.89, p = 0.017) and for Framingham risk score (β = 2.83, p<0.001).
Aortic unfolding defined by measuring aortic width was a reproducible and practical method with non-contrast cardiac CT and associated with age, body surface area, and hypertension. CAC score, a well-established surrogate marker of cardiovascular disease, is positively associated with aortic unfolding. Further study to evaluate aortic unfolding as a potential predictor of cardiovascular risk is warranted.
PMCID: PMC3995952  PMID: 24755938
14.  Combined Impact of Cardiorespiratory Fitness and Visceral Adiposity on Metabolic Syndrome in Overweight and Obese Adults in Korea 
PLoS ONE  2014;9(1):e85742.
Obesity, especially visceral obesity, is known to be an important correlate for cardiovascular disease and increased mortality. On the other hand, high cardiorespiratory fitness is suggested to be an effective contributor for reducing this risk. This study was conducted to determine the combined impact of cardiorespiratory fitness and visceral adiposity, otherwise known as fitness and fatness, on metabolic syndrome in overweight and obese adults.
A total of 232 overweight and obese individuals were grouped into four subtypes according to their fitness level. This was measured by recovery heart rate from a step test in addition to visceral adiposity defined as the visceral adipose tissue area to subcutaneous adipose tissue area ratio (VAT/SAT ratio). Associations of fitness and visceral fatness were analyzed in comparison with the prevalence of metabolic syndrome.
The high visceral fat and low fitness group had the highest prevalence of metabolic syndrome [Odds Ratio (OR) 5.02; 95% Confidence Interval (CI) 1.85–13.61] compared with the reference group, which was the low visceral adiposity and high fitness group, after adjustments for confounding factors. Viscerally lean but unfit subjects were associated with a higher prevalence of metabolic syndrome than more viscerally obese but fit subjects (OR 3.42; 95% CI 1.27–9.19, and OR 2.70; 95% CI 1.01–7.25, respectively).
Our study shows that visceral obesity and fitness levels are cumulatively associated with a higher prevalence of metabolic syndrome in healthy overweight and obese adults. This suggests that cardiorespiratory fitness is a significant modifier in the relation of visceral adiposity to adverse metabolic outcomes in overweight and obese individuals.
PMCID: PMC3893257  PMID: 24454926
15.  Quantification of Human Plasma-Busulfan Concentration by Liquid Chromatography-Tandem Mass Spectrometry 
Annals of Laboratory Medicine  2013;34(1):7-14.
Busulfan, an alkylating agent administered prior to hematopoietic stem cell transplantation, has a narrow therapeutic range and wide variability in metabolism. We developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for rapid and accurate quantification of plasma busulfan.
Busulfan was separated and detected using an LC system containing a C18 column equipped with MS/MS. The sample was eluted with a mobile phase gradient for a total run time of 10 min. Plasma busulfan concentration was quantified against a 6-point standard curve in a multiple reaction monitoring mode at mass-to-charge (m/z) 264.1 > 151.1. Precision, recovery, matrix effect, linearity, detection capability, carryover, and stability were evaluated. The range of plasma busulfan concentration was obtained by analyzing samples from 9 children receiving busulfan.
The coefficients of variation of within-run and within-laboratory precision were all below 5%. Recoveries were all within the range of 100-105%. Linearity was verified from 0 to 5,000 ng/mL. Limit of detection and limit of quantification were 1.56 and 25 ng/mL, respectively. Carryover rate was within allowable limits. Plasma busulfan concentration was stable for 2 weeks at -20℃ and -80℃, but decreased by 25% when the plasma was stored for 24 hr at room temperature, and by <5% in 24 hr at 4℃. The plasma busulfan concentrations were between 347 ng/mL and 5,076 ng/mL.
Our method using LC-MS/MS enables highly accurate, reproducible, and rapid busulfan monitoring with minimal sample preparation. The method may also enable safe and proper dosage.
PMCID: PMC3885779  PMID: 24422189
Busulfan; Drug monitoring; Tandem mass spectrometry; Liquid chromatography; Hematopoietic stem cell transplantation
16.  Torsade de pointes in liver transplantation recipient after induction of general anesthesia: a case report 
Torsade de pointes (TdP) is an uncommon and specific form of polymorphic ventricular tachycardia, associated with a prolonged QT interval. Prolongation of the QT interval is the most widely recognized electrophysiological abnormality in patients with liver cirrhosis. We observed a case of TdP leading to cardiopulmonary resuscitation after the induction of general anesthesia, in a patient with liver cirrhosis scheduled for emergency cadaveric donor liver transplantation. The patient had mild QT prolongation on preoperative electrocardiography with a corrected QT (QTc) interval of 455 ms. Drugs used in the preoperative period can elongate cardiac repolarization. Sevoflurane and 5-hydroxytryptamine type 3 receptor antagonists such as palonsetron, used during general anesthesia may have triggered further QT prolongation, producing a fatal condition such as TdP. More caution and consideration in selecting drugs for anesthetic management are necessary for liver cirrhosis patients, especially in patients with preoperative QT prolongation.
PMCID: PMC3927008  PMID: 24567820
Heart arrest; Liver transplantation; Long QT syndrome; Torsades de pointes
17.  Dendropanoxide Induces Autophagy through ERK1/2 Activation in MG-63 Human Osteosarcoma Cells and Autophagy Inhibition Enhances Dendropanoxide-Induced Apoptosis 
PLoS ONE  2013;8(12):e83611.
Anticancer effects of dendropanoxide (DP) newly isolated from leaves and stem of Dendropanax morbifera Leveille were firstly investigated in this study. DP inhibited cell proliferation and induced apoptosis in dose- and time-dependent manner in MG-63 human osteosarcoma cells, which was dependent on the release of cytochrome c to the cytosol and the activation of caspases. Moreover, the DP-treated cells exhibited autophagy, as characterized by the punctuate patterns of microtubule-associated protein 1 light chain 3 (LC3) by confocal microscopy and the appearance of autophagic vacuoles by MDC staining. The expression levels of ATG7, Beclin-1 and LC3-II were also increased by DP treatment. Inhibition of autophagy by 3-methyladenine (3-MA) and wortmannin (Wort) significantly enhanced DP-induced apoptosis. DP treatment also caused a time-dependent increase in protein levels of extracellular signal-regulated kinase 1 and 2 (ERK1/2), and inhibition of ERK1/2 phosphorylation with U0126 resulted in a decreased DP-induced autophagy that was accompanied by an increased apoptosis and a decreased cell viability. These results indicate a cytoprotective function of autophagy against DP-induced apoptosis and suggest that the combination of DP treatment with autophagy inhibition may be a promising strategy for human osteosarcoma control. Taken together, this study demonstrated for the first time that DP could induce autophagy through ERK1/2 activation in human osteosarcoma cells and autophagy inhibition enhanced DP-induced apoptosis.
PMCID: PMC3866153  PMID: 24358301
18.  Clinical Characteristics of Pediatric Thalassemia in Korea: A Single Institute Experience 
Journal of Korean Medical Science  2013;28(11):1645-1649.
Few literatures have elaborated on the clinical characteristics of children with thalassemia from low-prevalence areas. A retrospective analysis was conducted on children genetically confirmed with thalassemia at Seoul National University Children's Hospital in Korea. Nine children (1α thalassemia trait, 6β thalassemia minor, 2β thalassemia intermedia) were diagnosed with thalassemia at median age of 4.3 yr old with median hemoglobin of 9.7 g/dL. Seven (78%) children were incidentally found to be anemic and only 2 with β thalassemia intermedia had presenting symptoms. Five children (56%) were initially misdiagnosed with iron deficiency anemia. Despite the comorbidities due to α thalassemia mental retardation syndrome, the child with α thalassemia trait had mild hematologic profile. Children with β thalassemia intermedia had the worst phenotypes due to dominantly inherited mutations. None of the children was transfusion dependent and most of them had no complications associated with thalassemia. Only 1 child (11%) with codon 60 (T→A) mutation of the HBB gene needed red blood cell transfusions. He also had splenomegaly, cholelithiasis, and calvarial vault thickening. Pediatricians in Korea must acknowledge thalassemia as a possible diagnosis in children with microcytic hypochromic hemolytic anemia. High level of suspicion will allow timely diagnosis and managements.
PMCID: PMC3835508  PMID: 24265529
α-Thalassemia; β-Thalassemia; Genotype; Phenotype; Child; Korea
19.  Epigallocatechin Gallate Induces Expression of Heme Oxygenase-1 in Endothelial Cells via p38 MAPK and Nrf-2 that Suppresses Pro-inflammatory Actions of TNF-α 
Epigallocatechin gallate (EGCG), the major polyphenol in green tea, acutely stimulates production of nitric oxide (NO) from vascular endothelium to reduce hypertension, and improve endothelial dysfunction in SHR rats. Herein, we explored additional mechanisms whereby EGCG may mediate beneficial cardiovascular actions. When compared with vehicle-treated controls, EGCG treatment (2.5 μM, 8 h) of human aortic endothelial cells (HAEC) caused a ~3-fold increase in hemeoxygenase-1 (HO-1) mRNA and protein with comparable increases in HO-1 activity. This was unaffected by pre-treatment of cells with wortmannin, LY294002, PD98059, or L-NAME (PI 3-kinase, MEK, and NO synthase inhibitors, respectively). Pre-treatment of HAEC with SB203580 (p38 MAPK inhibitor) or siRNA knockdown of p38 MAPK completely blocked EGCG-stimulated induction of HO-1. EGCG treatment also inhibited TNF-α-stimulated expression of VCAM-1 and decreased adhesion of monocytes to HAEC. siRNA knockdown of HO-1, p38 MAPK, or Nrf-2 blocked these inhibitory actions of EGCG. In HAEC transiently transfected with a human HO-1 promoter luciferase reporter (or an isolated Nrf-2 responsive region), luciferase activity increased in response to EGCG. This was inhibitable by SB203580 pre-treatment. EGCG-stimulated expression of HO-1 and Nrf-2 was blocked by siRNA knockdown of Nrf-2 or p38 MAPK. Finally, liver from mice chronically treated with EGCG had increased HO-1 and decreased VCAM-1 expression. Thus, in vascular endothelium, EGCG requires p38 MAPK to increase expression of Nrf-2 that drives expression of HO-1 resulting in increased HO-1 activity. Increased HO-1 expression may underlie anti-inflammatory actions of EGCG in vascular endothelium that may help mediate beneficial cardiovascular actions of green tea.
PMCID: PMC3296830  PMID: 22137262
Epigallocatechin gallate (EGCG); hemeoxygenase-1; p38 kinase; nuclear factor-E2-related factor-2; endothelium
20.  The Effect of Gingko Biloba on Hearing in Mice with Noise-Induced Temporary Threshold Shift 
Korean Journal of Audiology  2013;17(2):74-77.
Background and Objectives
Gingko biloba extract is known for enhancing blood circulation, scavenging free radicals, and antagonizing against platelet-activating factor. This study evaluated the effect of Gingko biloba on the noise-induced temporary threshold shift of hearing.
Materials and Methods
Temporary threshold shift was induced by exposing mice to 110 dB SPL sound for 1 hour. The experimental group consisted of mice fed Gingko biloba [3 mg/kg, 6 mg/kg, and 12 mg/kg in 0.5% carboxymethyl cellulose (CMC)] for 7 days before noise exposure. CMC solution without Gingko biloba was fed to control mice. Hearing threshold was measured by auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE).
The hearing threshold increased after noise exposure and recovered to normal within 5 days in all groups. Compared to control mice (fed CMC solution only), mice fed Gingko biloba showed more rapid recovery of ABR threshold at 16 kHz in all three experimental groups. At the other frequencies, there was no significant change in hearing recovery in the Gingko biloba groups. There was no difference in DPOAE between groups.
Temporary threshold shift of hearing after noise exposure was partly affected by oral Gingko biloba.
PMCID: PMC3936537  PMID: 24653910
Hearing loss; Noise-induced; Temporary threshold shift; Gingko biloba; Hearing
21.  Pharmacogenetic Study of Deferasirox, an Iron Chelating Agent 
PLoS ONE  2013;8(5):e64114.
Transfusion-associated iron overload induces systemic toxicity. Deferasirox, a convenient long acting oral agent, has recently been introduced in clinical practice with a promising efficacy. But there are some patients who experience drug-related toxicities and cannot tolerate it. To investigate effect of genetic variations on the toxicities and find optimal target population, we analyzed the genetic polymorphisms of UDP-glucuronosyltransferase 1A (UGT1A) subfamily, multi-drug resistance-associated protein 2 (MRP2) and breast cancer resistance protein (BCRP). A total of 20 functional genetic polymorphisms were analyzed in 98 patients who received deferasirox to reduce transfusion-induced iron overload. We retrospectively reviewed the medical records to find out the drug-related toxicities. Fifteen (15.3%) patients developed hepatotoxicity. Patients without wild-type allele carrying two MRP2 haplotypes containing −1774 del and/or −24T were at increased risk of developing hepatotoxicity compared to patients with the wild-type allele on multivariate analysis (OR = 7.17, 95% CI = 1.79–28.67, P = 0.005). Creatinine elevation was observed in 9 patients (9.2%). Body weight ≥40 kg and homozygosity for UGT1A1*6 were risk factors of creatinine elevation (OR = 8.48, 95% CI = 1.7–43.57, P = 0.010 and OR = 14.17, 95% CI = 1.34–150.35, P = 0.028). Our results indicate that functional genetic variants of enzymes to metabolize and transport deferasirox are associated with drug-related toxicities. Further studies are warranted to confirm the results as the pharmacogenetic biomarkers of deferasirox.
PMCID: PMC3667856  PMID: 23737969
22.  Effects of veraguensin and galgravin on osteoclast differentiation and function 
Cytotechnology  2012;64(3):315-322.
The dried flower buds of Magnolia sp. are widely used as herbal medicines because of their anti-inflammatory, anti-malarial and anti-platelet activities. Here, we found that veraguensin and galgravin, lignan compounds derived from Magnolia sp., dose-dependently inhibited osteoclast formation in co-cultures of bone marrow cells and osteoblastic cells. These compounds also inhibited receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclast differentiation in RAW264.7 cells and bone marrow macrophages. In the RANKL-induced signaling pathway, veraguensin and galgravin reduced p38 phosphorylation and suppressed the expression of c-Fos, a key transcription factor for osteoclastogenesis. Veraguensin and galgravin also inhibited osteoclastic pit formation, which was accompanied by decreased mature osteoclast viability. In conclusion, these results indicate that veraguensin and galgravin can inhibit bone resorption and may offer novel compounds for the development of drugs to treat bone-destructive diseases such as osteoporosis.
PMCID: PMC3386385  PMID: 22526488
Veraguensin.; Galgravin; RANKL; Osteoclast; p38; c-Fos
23.  Staphylococcal enterotoxin specific IgE and asthma: a systematic review and meta-analysis 
Asia Pacific Allergy  2013;3(2):120-126.
Recent literature suggests that Staphylococcal enterotoxin specific IgE may be a risk factor for asthma.
To investigate the associations between Staphylococcal enterotoxin sensitization and asthma.
A systematic review and meta-analysis was performed for relevant case-control or population-based studies, published in the peer-reviewed journals until February 2013. Data were extracted on study designs, subjects, definitions and the prevalence of Staphylococcal enterotoxin sensitization.
A total of 683 studies were initially identified, of which 7 studies finally met the inclusion criteria (5 case-control and 2 population-based studies). All the included studies reported higher prevalence of the sensitization in asthmatics than in controls, despite clinical and methodological heterogeneity. In a meta-analysis, the pooled odds ratio of the sensitization for asthma was 2.95 (95% confidence intervals 2.28-3.82).
Staphylococcal enterotoxin sensitization was significantly associated with asthma. The mechanisms of associations warrant further elucidation.
PMCID: PMC3643054  PMID: 23667836
Asthma; Staphylococcus; Meta-analysis
24.  Cardiopulmonary Fitness Is Independently Associated with Insulin Resistance in Non-Diabetes Mellitus Patients of a University Hospital in Korea 
Korean Journal of Family Medicine  2013;34(2):139-144.
Insulin resistance, decreased response of peripheral tissue to normal insulin levels, is known to be related to cardiometabolic diseases. Cardiopulmonary fitness is also considered to be related to these comorbidities. Therefore, we investigated the relationship between insulin resistance and cardiopulmonary fitness by performing a 3-minute step test in a Korean non-diabetes mellitus (DM) population.
A total of 118 non-DM subjects were enrolled during their routine health check-up. Insulin resistance was measured by calculating homeostatic model assessment-insulin resistance (HOMA-IR), and a 3-minute step test was performed to measure cardiopulmonary fitness.
Post-60 seconds exercise heart rate after 3-minute test (R60 heart rate) was correlated with age (r = -0.21, P = 0.02), education (r = 0.17, P = 0.04), body mass index (r = 0.23, P = 0.01), waist circumference (r = 0.28, P < 0.01), fasting insulin (r = 0.28, P < 0.01), HOMA-IR (r = 0.25, P < 0.01), low density lipoprotein-cholesterol (r = 0.28, P < 0.01), high sensitivity C-reactive protein levels (r = 0.22, P = 0.02), and baseline heart rate (r = 0.56, P < 0.01). In a step-wise multiple regression analysis, baseline heart rate (β = 0.79, P < 0.001), HOMA-IR (β = 0.65, P = 0.02), and systolic blood pressure (β = 0.15, P = 0.03) were identified as explanatory variables for R60 heart rates.
Our results suggested that cardiopulmonary fitness was associated with insulin resistance in non-DM patients of a university hospital in Korea. Further studies are needed to elucidate the underlying mechanisms.
PMCID: PMC3611102  PMID: 23560213
Insulin Resistance; Physical Fitness; Exercise Test
25.  Impact of Diabetes on Oncologic Outcome of Colorectal Cancer Patients: Colon vs. Rectal Cancer 
PLoS ONE  2013;8(2):e55196.
To evaluate the impact of diabetes on outcomes in colorectal cancer patients and to examine whether this association varies by the location of tumor (colon vs. rectum).
Patients and methods
This study includes 4,131 stage I-III colorectal cancer patients, treated between 1995 and 2007 (12.5% diabetic, 53% colon, 47% rectal) in South Korea. Cox proportional hazards modeling was used to determine the prognostic influence of DM on survival endpoints.
Colorectal cancer patients with DM had significantly worse disease-free survival (DFS) [hazard ratio (HR) 1.17, 95% confidence interval (CI): 1.00–1.37] compared with patients without DM. When considering colon and rectal cancer independently, DM was significantly associated with worse overall survival (OS) (HR: 1.46, 95% CI: 1.11–1.92), DFS (HR: 1.45, 95% CI: 1.15–1.84) and recurrence-free survival (RFS) (HR: 1.32, 95% CI: 0.98–1.76) in colon cancer patients. No association for OS, DFS or RFS was observed in rectal cancer patients. There was significant interaction of location of tumor (colon vs. rectal cancer) with DM on OS (P = 0.009) and DFS (P = 0.007).
This study suggests that DM negatively impacts survival outcomes of patients with colon cancer but not rectal cancer.
PMCID: PMC3566217  PMID: 23405123

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