A genome-wide association study on thyroid function and anti-thyroid peroxidase antibodies in Koreans

Kwak, Soo Heon,Park, Young Joo,Go, Min Jin,Lee, Kyu Eun,Kim, Su-jin,Choi, Hoon Sung,Kim, Tae Hyuk,Choi, Sung Hee,Lim, Soo,Kim, Ki Woong,Park, Do Joon,Kim, Sung Soo,Lee, Jong-Young,Park, Kyong Soo,Jang IRL Press 2014 Human molecular genetics Vol.23 No.16

<P>Genetic factors are thought to be an important determinant of thyroid function and autoimmunity. However, there are limited data on genetic variants in Asians. In this study, we performed a genome-wide association study on plasma thyroid-stimulating hormone (TSH) and free thyroxine (fT<SUB>4</SUB>) concentration and anti-thyroid peroxidase (anti-TPO) antibody positivity in 4238 Korean subjects. In the Stage 1 genome scan, 3396 participants from the Ansung cohort were investigated using 1.42 million genotyped or imputed markers. In the Stage 2 follow-up, 10 markers were genotyped in 842 participants from the Korean Longitudinal Study on Health and Aging cohort. An intronic variant in <I>VAV3,</I> rs12126655, which has been reported in Europeans, was significantly associated with plasma TSH concentration in the joint Stages 1 and 2 analyses (<I>P</I> = 2.2 × 10<SUP>−8</SUP>). We observed that a novel variant, rs2071403, located 75 bp proximal to the translational start site of <I>TPO</I> was significantly associated with plasma anti-TPO antibody positivity in the joint Stages 1 and 2 analyses (<I>P</I> = 1.3 × 10<SUP>−10</SUP>). This variant had a marginal sex-specific effect, and its association was more significant in females. Subjects possessing the rs2071403A allele, associated with an absence of the anti-TPO antibody, had decreased TPO mRNA expression in their thyroid tissue. Another intronic variant of <I>HLA-DPB2</I>, rs733208, had a suggestive association with anti-TPO antibody positivity (<I>P</I> = 4.2 × 10<SUP>−7</SUP>). In conclusion, we have identified genetic variants that are strongly associated with TSH level and anti-TPO antibody positivity in Koreans. Further replications and meta-analysis are required to confirm these findings.</P>

Establishment of Waternode Stations for Water Quality Monitoring by IP-USN

Kwak, Pill Jae,Kim, Seog Ku,Yun, Sang Leen,Kang, Sung Won,Lee, Hyun Dong,Lee, Joo Yeon,Ban, Hyo Jin,Yang, Keun Ho,Oh, Hee Jae,Kim, Young Sung Trans Tech Publications, Ltd. 2011 Materials science forum Vol.695 No.-

<P>Waternode station is a floating composite water quality monitoring device. The waternode station houses the multiple water quality measurement devices, control panel for wireless communication and solar cells for applying electric power. The floating devices are classified into general model with vertical dropping system and river model without vertical dropping system. The water quality measurement device measures pH, water temperature, conductivity, dissolved oxygen, turbidity and nitrate. And it measures all parameters simultaneously. The control panel is used for IP-USN system. USN (Ubiquitous Sensor Network) is a network system by water quality measurement devices. IP-USN is a USN system that identifies particular sensor connected to the internet. The data information is transferred by wireless modem based on TFB (Triple Frequency Band). Field application results showed that the waternode station is a reliable and cost-effective water quality monitoring solutions.</P>

Association of variations in TPH1 and HTR2B with gestational weight gain and measures of obesity.

Kwak, Soo Heon,Park, Byoung Lae,Kim, Hail,German, Michael S,Go, Min Jin,Jung, Hye Seung,Koo, Bo Kyong,Cho, Young Min,Choi, Sung Hee,Cho, Yoon Shin,Shin, Hyoung Doo,Jang, Hak C,Park, Kyong Soo NAASO, the Obesity Society 2012 Obesity Vol.20 No.1

<P>Serotonin is involved in appetite regulation and energy homeostasis. Recently, it has been reported that 5-hydroxytryptamine receptor 2B (Htr2b) and tryptophan hydroxylase 1 (Tph1) play major role in β-cell proliferation in mouse during pregnancy. We investigated the genetic association of HTR2B and TPH1 with risk of gestational diabetes mellitus (GDM) and measures of obesity, in 869 Korean GDM women and carefully selected 632 nondiabetic control subjects. Six single-nucleotide polymorphisms (SNPs) in HTR2B and ten SNPs in TPH1 were selected for genotyping according to their tagging status. Genetic variants in HTR2B and TPH1 were not associated with the risk of GDM. In GDM women, SNPs of TPH1 were significantly associated with weight gain during pregnancy. In nondiabetic controls, SNPs of TPH1 were associated with waist circumference and BMI. We also found that a variant of TPH1 (rs623580) was associated with BMI in a genome-wide association study comprised of 8,842 subjects. Although genetic variants in HTR2B and TPH1 were not associated with risk of GDM, we found significant association of these variants with measures of obesity. However, further replication studies in a different population are required to confirm our findings.</P>

Simultaneous detection of fungal, bacterial, and viral pathogens in insects by multiplex PCR and capillary electrophoresis

Kwak, Kyu-Won,Nam, Sung-Hee,Choi, Ji-Young,Lee, Seokhyun,Kim, Hong Geun,Kim, Sung-Hyun,Park, Kwan-Ho,Han, Myung-Sae Korean Society of Sericultural Science 2015 International Journal of Industrial Entomology Vol.30 No.2

Beetles Protaetia brevitarsis seulensis Kolbe (Coleoptera: Cetoniidae) and Allomyrina dichotoma Linn. (Coleoptera: Scarabaeidae) are widely used in traditional medicine, and the number of insect-rearing farms is increasing in South Korea. The purpose of this study was to establish a multiplex PCR-based assay for rapid simultaneous detection of multiple pathogens causing insect diseases. Six insect parasites such as fungi Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Cordycipitaceae) and Metarhizium anisopliae (Metschn.) Sorokin (Hypocreales: Clavicipitaceae), bacteria Bacillus thuringiensis Berliner (Bacillales: Bacillaceae), Pseudomonas aeruginosa Migula (Pseudomonadales: Pseudomonadaceae), and Serratia marcescens Bizio (Enterobacteriales: Enterobacteriaceae), and Oryctes rhinoceros nudivirus were chosen based on the severity and incidence rate of insect diseases in South Korea. Pathogen-specific primers were designed and successfully applied for simultaneous detection of multiple infectious agents in farm-bred insects P. b. seulensis and A. dichotoma using multiplex PCR and high resolution capillary electrophoresis. Our results indicate that multiplex PCR is an effective and time-saving method for simultaneous detection of multiple infections in insects, and the QIAxcel capillary electrophoresis system is useful for quantitative evaluation of the individual impact of each infectious agent on the severity of insect disease. The approach designed in this study can be utilized for rapid and accurate diagnostics of infection in insect farms.

Analysis of the Inhibitory Effect of two Bacterial Strains on Metarhizium anisopliae Induced Fatality Rates in Protaetia Brevitarsis

Kwak, Kyu-Won,Nam, Sung-Hee,Park, Kwan-Ho,Lee, Heuisam,Han, Myung-Sae Korean Society of Sericultural Science 2018 International Journal of Industrial Entomology Vol.37 No.1

Bacterial species, Bacillus amyloliquefaciens and Lactobacillus species (L. sp.5-1), are known to inhibit the growth of pathogenic bacteria and fungi. Metarhizium anisopliae is a pathogenic fungal species which causes fatal damage to P. brevitarsis populations. Therefore, we investigated the inhibitory effect of B. amyloliquefaciens and L. sp. 5-1 on M. anisopliae induced fatality rates in P. brevitarsis. Samples of M. anisopliae-infected sawdust were treated with strain B. amyloliquefaciens KACC10116, strain L. sp. 5-1 KACC19351, and a combination of the two. P. brevitarsis were fed treated sawdust samples, and their subsequent fatality rate was monitored. The fatality rate fell below 1.5% after 10 days and decreased by approximately 40% after 15 days. On average, the fatality rate decreased by 20%, compared to the control. The difference in the decrease in fatality rate between B. amyloliquefaciens treatment and L. sp. 5-1 treatment was not significant. Results indicate that both strains exhibit high anti-fungal activity, which may be useful in environmental purification efforts. These strains may be used for effective prevention of fungal infection in P. brevitarsis.

Comparing the mortality of Protaetia brevitarsis seulensis (Coleoptera: Cetoniidae) caused by entomopathogenic bacteria and Serratia marcescens (Enterobacteriales: Enterobacteriaceae)

Kwak, Kyu Won,Han, Myung Sae,Nam, Sung Hee,Choi, Ji Young,Lee, Seok Hyun,Kim, Hong Geun,Park, Kwan Ho Korean Society of Sericultural Science 2015 International Journal of Industrial Entomology Vol.30 No.2

To investigate whether Serratia marcescens (Enterobacteriales: Enterobacteriaceae) isolated from Protaetia brevitarsis seulensis (Coleoptera: Cetoniidae) acts as an opportunistic bacterium in peroral infection, the primary entomopathogenic bacteria Bacillus thuringiensis (Bacillales: Bacillaceae) and Paenibacillus popilliae (Eubacteriales: Bacillaceae) were added to sawdust to perform a bioassay experiment. We found that peroral infection caused by S. marcescens could be fatal beyond a concentration of $4{\times}10^8pfu/mL$ in $2^{nd}$ stage P. b. seulensis larvae and at $6{\times}10^8pfu/mL$ in $3^{rd}$ stage P. b. seulensis larvae. In particular, mortality resulting from a combination of P. popilliae and S. marcescens was markedly increased in $2^{nd}$ stage P. b. seulensis larvae. Therefore, we confirmed that mortality was increased when S. marcescens was infected together with other entomopathogenic bacteria, and that peroral infection itself can be fatal beyond certain concentrations.

Adaptive Writeback-aware Cache Management Policy for Lifetime Extension of Non-volatile Memory

Sang-Ho Hwang,Ju Hee Choi,Jong Wook Kwak 대한전자공학회 2017 Journal of semiconductor technology and science Vol.17 No.4

In this paper, we propose Adaptive Writeback-aware Cache management (AWC) to prolong the lifetime of non-volatile main memory systems by reducing the number of writebacks. The last-level cache in AWC is partitioned into Least Recently Used (LRU) segment and LRU using Dirty block Precedence (DP-LRU) segment. The DP-LRU segment evicts clean blocks first for giving reuse opportunity to dirty blocks. AWC can also determine the efficient size of DP-LRU segment for reducing the number of writebacks according to memory access patterns of programs. In the performance evaluation, we showed that AWC reduced the number of writebacks up to 29% and 46%, and saved the energy of a main memory system up to 23% and 49% in a single-core and multi-core, respectively. AWC also reduced the runtime by 1.5% and 3.2% on average compared to previous cache managements for nonvolatile main memory systems, in a single-core and a multi-core, respectively.

Two Bayesian methods for sample size determination in clinical trials

Kwak, Sang-Gyu,Kim, Dal-Ho,Shin, Im-Hee,Kim, Ho-Gak,Kim, Sang-Gyung The Korean Data and Information Science Society 2010 한국데이터정보과학회지 Vol.21 No.6

Sample size determination is very important part in clinical trials because it influences the time and the cost of the experimental studies. In this article, we consider the Bayesian methods for sample size determination based on hypothesis testing. Specifically we compare the usual Bayesian method using Bayes factor with the decision theoretic method using Bayesian reference criterion in mean difference problem for the normal case with known variances. We illustrate two procedures numerically as well as graphically.

Prediction of Resistance to Standard Intravenous Immunoglobulin Therapy in Kawasaki Disease

Sang Min Lee,Jeong Bong Lee,Young Bin Go,Ho Young Song,Byung Jin Lee,Ji Hee Kwak 대한심장학회 2014 Korean Circulation Journal Vol.44 No.6

Background and Objectives: Ten to twenty percent of children with Kawasaki disease (KD) do not respond to initial intravenous immunoglobulin (IVIG) treatment. If untreated, approximately 15% to 25% of KD patients have complications. The aim of this study was to find useful predictors of responsiveness to initial IVIG treatment in KD. Subjects and Methods: We retrospectively reviewed medical records of 91 children diagnosed with KD at Myong Ji Hospital from March 2012 to April 2014. Before and after (24 hours to 36 hours) IVIG treatment, the following laboratory data were obtained: hemoglobin (Hb) level, white blood cell count, proportion of neutrophil, lymphocyte and eosinophil, platelet count, erythrocyte sedimentation rate (ERS), Creactive protein (CRP), creatine kinase (CK), creatine kinase MB (CK-MB), and N-terminal pro-brain natriuretic peptide (NT-proBNP). Subjects were then divided into two groups: IVIG-responsive or IVIG-resistant. Results: Of 91 patients, 11 (12%) required retreatment. By univariate analysis, before-IVIG laboratory parameters of white blood cell count, % neutrophil, ERS, CRP, sodium, CK, CK-MB, and NT- proBNP were significantly different between IVIG-responsive and IVIG-resistant patient groups. In the after-IVIG laboratory parameters, Hb level, white blood cell count, % neutrophil, % lymphocyte, CRP, CK, CK-MB, and NT-pro- BNP were significantly different between the two groups. While the mean-differences were not statistically significant, fractional change (FC)-CRP and FC-% neutrophil showed significant difference. By multivariate analysis, FC-CRP was confirmed to be an independent predictor for initial IVIG resistance. Conclusion: Fractional change-C-reactive protein might be a useful and important value for predicting initial IVIG resistance in KD patients.

A Case of Significant Endobronchial Injury due to Recurrent Iron Pill Aspiration

Kwak, Joo-Hee,Koo, Gun Woo,Chung, Sung Jun,Park, Dong Won,Kwak, Hyun Jung,Moon, Ji-Yong,Kim, Sang-Heon,Sohn, Jang Won,Yoon, Ho Joo,Shin, Dong Ho,Park, Sung Soo,Pyo, Ju Yeon,Oh, Young-Ha,Kim, Tae-Hyung The Korean Academy of Tuberculosis and Respiratory 2015 Tuberculosis and Respiratory Diseases Vol.78 No.4

Gastric mucosal damage by iron pills is often reported. However, iron pill aspiration is uncommon. Oxidation of the impacted iron pill causes bronchial mucosal damage that progresses to chronic bronchial inflammation, necrosis, endobronchial stenosis and rarely, perforation. We reported a case of a 92-year-old woman with chronic productive cough and significant left-sided atelectasis. Bronchoscopy revealed substantial luminal narrowing with exudative inflammation of the left main bronchus. Bronchial washing cytology showed necroinflammatory exudate and a small amount of brown material. Mucosal biopsy showed diffuse brown pigments indicative of ferrous pigments, crystal deposition, and marked tissue degeneration. After vigorous coughing, she expectorated dark sediments and her symptoms and radiological abnormalities improved. There are a few such reports worldwide; however, this was the first case reported in Korea. Careful observation of aspiration-prone patients and early detection of iron pill aspiration may prevent iron pill-induced bronchial injury.