Polymyxin B, scavenger of endotoxin, enhances isolation yield and<i>in vivo</i>function of islets

Park, Sang G.,Kim, Jae H.,Oh, Ji H.,Lee, Han N.,Park, Ho S.,Chung, Sung S.,Lee, Ye J.,Lee, Yeon Y.,Jung, Hye S.,Park, Kyong S. Wiley (Blackwell Publishing) 2010 Transplant international Vol.23 No.3

Incidence and Characteristics of Scarlet Fever, South Korea, 2008–2015

Park, Duck Woong,Kim, Sun-Hee,Park, Jung Wook,Kim, Min-Ji,Cho, Sun Ju,Park, Hye Jung,Jung, So Hyang,Seo, Mi Hee,Lee, Yong Seok,Kim, Byung Hee,Min, Hyeran,Lee, Su Ya,Ha, Dong Ryong,Kim, Eun Sun,Hong, Y Centers for Disease Control and Prevention 2017 Emerging infectious diseases Vol.23 No.4

<P>The incidence rate for scarlet fever in South Korea is rising. During 2008–2015, we collected group A <I>Streptococcus</I> isolates and performed <I>emm</I> and exotoxin genotyping and disk-diffusion antimicrobial tests. Scarlet fever in South Korea was most closely associated with <I>emm</I> types <I>emm</I>4, <I>emm</I>28, <I>emm</I>1, and <I>emm</I>3. In 2015, tetracycline resistance started increasing.</P>

Grb2-associated binder-1 is required for extrafusal and intrafusal muscle fiber development

Park, So Y.,Jang, So Y.,Shin, Yoon K.,Yoon, Byeol A.,Lee, Hye J.,Park, Hwan T. Lippincott Williams & Wilkins 2017 NeuroReport Vol.28 No.10

<P>The neuregulin-1 (NRG1) signaling pathway plays an important role in the development of the peripheral neuromuscular system, including in muscle spindle and postnatal myelination. We previously showed that NRG1 on the axonal membrane regulates peripheral nerve myelination through Grb2-associated binder 1 (Gab1),a scaffolding mediator of receptor tyrosine kinase signaling. Here, we determined the role of Gab1 in the development of muscles and the muscle spindle using muscle-specific conditional Gab1 knockout mice. The mutant mice showed general retardation in muscular growth and hypotrophy of extrafusal muscle fibers. In addition, the muscle-specific Gab1 knockout mutant exhibited significant underdevelopment of muscle spindles, which are normally regulated by NRG1, and abnormal proprioceptive behavior. Furthermore, the selective knockdown of Gab1 in C2C12 muscle cells reduced NRG1-induced expression of Egr3, a critical transcription factor for muscle spindle development. However, Gab2 knockout mice did not show any defects in the development of muscles or muscle spindles. Our findings suggest that Gab1 is an essential signaling molecule in mediating axonal NRG1 signaling for the development of both extrafusal and intrafusal muscle fibers. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.</P>

Interaction effect of serum 25-hydroxyvitamin D levels and CYP1A1, CYP1B1 polymorphisms on blood pressure in an elderly population

Park, Hye Y.,Kim, Jin H.,Bae, Sanghyuk,Choi, Yi Y.,Park, Jae Y.,Hong, Yun-Chul Wolters Kluwer Health | Lippincott Williams Wilkin 2015 Journal of Hypertension Vol.33 No.1

OBJECTIVE:: Hypertension and vitamin D deficiency are prevalent worldwide, especially in the elderly. Considering the possibility of gene–environment contributions to disease development, we evaluated the influence of certain cytochrome P450 polymorphisms and vitamin D levels on blood pressure (BP). METHODS:: We measured serum 25-hydroxyvitamin D levels [25(OH)D] and BP in 535 individuals over 60 years old and identified single-nucleotide polymorphisms (SNPs) of CYP1A1 and CYP1B1 in lymphocyte DNA. Repeated measure analyses were used to determine the statistical association. RESULTS:: The relationship between 25(OH)D and SBP or DBP was inversely significant, and influence of several CYP1A1 and CYP1B1 SNPs on BP was found across different genotypes. Estimated effect of 25(OH)D levels on BP in the group with higher risky genotype scores of selected SNPs (rs4646421, rs2551188, and rs1056836) was greater (&bgr; = −2.841, P = 0.004 for SBP; &bgr; = −2.035, P = 0.001 for DBP) than the group with lower genotype score (&bgr; = −0.878, P = 0.347 for SBP; &bgr; = 0.037, P = 0.947 for DBP), and synergistic interaction between vitamin D levels and genotype variations was observed (P-interaction = 0.081 for SBP and 0.008 for DBP). When stratified by the hypertension medication status, interaction effect was found only in individuals taking medication (P-interaction = 0.004 for SBP and 0.001 for DBP). CONCLUSION:: Genetic variations in CYP1A1 and CYP1B1 and the serum levels of 25(OH)D showed synergistic effect on BP, especially in individuals currently in treatment for hypertension.

항암화학요법으로 인한 말초신경병증 환자의 한방치험 1례

이지혜(Ji Hye Lee),박혜림(Hye Lim Park),이혜윤(Hye Yun Lee),조민경(Min Kyoung Cho),홍미나(Mi Na Hong),한창우(Chang Woo Han),최준용(Jun Yong Choi),박성하(Seong Ha Park),권정남(Jung Nam Kwon),이인(In Lee),홍진우(Jin Woo Hong),김소연(So Y 한의병리학회 2014 동의생리병리학회지 Vol.28 No.5

Effect of crotonaldehyde on the induction of HO-1 expression in A549 cells

Seung Eun Lee,Hye Rim Park,Hong Duck Yun,Hyemi Kim,진영호,Cheung-Seog Park,Hyun-Jong Ahn,JeongJeCho,Yong Seek Park,Y. S. Park 대한독성 유전단백체 학회 2017 Molecular & cellular toxicology Vol.13 No.2

Cigarette smoke contains approximately 5,000 chemical components, including reactive chemicals and free radicals that are associated with an increased risk of chronic obstructive pulmonary disease (COPD). Cigarette smoke is also known to promote inflammation as part of various inflammatory airway diseases. Crotonaldehyde (CRA) is a highly toxic α, β-unsaturated aldehyde that is a major component of cigarette smoke. Exposure to CRA has been previously shown to result in adverse effects on respiratory health. Heme oxygenase-1 (HO-1) is an inducible enzyme that is activated by various stress-inducing stimuli to perform a diverse range of physiological functions, including anti-oxidant, anti-apoptotic, and anti-inflammatory effects. The present study aimed to investigate the effect of CRA stimulation on HO-1 expression in human lung adenocarcinoma epithelial (A549) cells. Stimulation of cells with CRA was shown to result in upregulated HO-1 expression via the induction of nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation, and activation of the p38 mitogen-activated protein kinase (MAPK) pathway. Furthermore, zinc protoporphyrin (ZnPP; a specific HO-1 inhibitor) was used to inhibit HO-1 activity, and this was shown to cause a significant increase in the rate of apoptosis of CRAexposed cells. Taken together, these results suggest that HO-1 exerts an anti-apoptotic effect in CRA-exposed human lung adenocarcinoma epithelial cells, and thus protects cells against CRA-induced oxidative stress.

Effect of crotonaldehyde on the induction of COX-2 expression in human endothelial cells

Seung Eun Lee,Hye Rim Park,Hyemi Kim,Yeoum Choi,Young-Ho Jin,Cheung-Seog Park,Hyun-Jong Ahn,Jeong-Je Cho,Yong Seek Park,Y. S. Park 대한독성 유전단백체 학회 2017 Molecular & cellular toxicology Vol.13 No.3

Cyclooxygenase-2 (COX-2), an inducible isoform protein, regulates diverse biological actions in vascular pathophysiology. COX-2 is induced in response to numerous stimuli, which results in prostaglandin (PG) production related to inflammation. Crotonaldehyde (CRA) is an extremely toxic α, β-unsaturated aldehyde and a major compound found in cigarette smoke. α, β-Unsaturated aldehyde in cigarette smoke is thought to mediate inflammation and vascular dysfunction. In this study, we evaluated the effect of CRA stimulation on COX-2 expression in human umbilical vein endothelial cells. CRA-stimulated COX-2 induction was accompanied by enhanced p38 phosphorylation and PGE2 generation. However, CRA-induced PGE2 production was reduced by pretreatment with an inhibitor of p38 MAPK. These results demonstrated that in human endothelial cells, CRA-induced COX-2-dependent PGE2 generation was mediated by p38 MAPK, and CRA may play a role in the development of inflammation.

An Improved Photovoltaic System Output Prediction Model under Limited Weather Information

Park, Sung-Won,Son, Sung-Yong,Kim, Changseob,LEE, Kwang Y.,Hwang, Hye-Mi The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.5

The customer side operation is getting more complex in a smart grid environment because of the adoption of renewable resources. In performing energy management planning or scheduling, it is essential to forecast non-controllable resources accurately and robustly. The PV system is one of the common renewable energy resources in customer side. Its output depends on weather and physical characteristics of the PV system. Thus, weather information is essential to predict the amount of PV system output. However, weather forecast usually does not include enough solar irradiation information. In this study, a PV system power output prediction model (PPM) under limited weather information is proposed. In the proposed model, meteorological radiation model (MRM) is used to improve cloud cover radiation model (CRM) to consider the seasonal effect of the target region. The results of the proposed model are compared to the result of the conventional CRM prediction method on the PV generation obtained from a field test site. With the PPM, root mean square error (RMSE), and mean absolute error (MAE) are improved by 23.43% and 33.76%, respectively, compared to CRM for all days; while in clear days, they are improved by 53.36% and 62.90%, respectively.

High-throughput single-cell quantification using simple microwell-based cell docking and programmable time-course live-cell imaging

Park, Min Cheol,Hur, Jae Young,Cho, Hye Sung,Park, Sang-Hyun,Suh, Kahp Y. Royal Society of Chemistry 2011 Lab on a chip Vol.11 No.1

<P>Extracting single-cell information during cellular responses to external signals in a high-throughput manner is an essential step for quantitative single-cell analyses. Here, we have developed a simple yet robust microfluidic platform for measuring time-course single-cell response on a large scale. Our method combines a simple microwell-based cell docking process inside a patterned microfluidic channel, with programmable time-course live-cell imaging and software-aided fluorescent image processing. The budding yeast, <I>Saccharomyces cerevisiae</I><I>(S. cerevisiae)</I>, cells were individually captured in microwells by multiple sweeping processes, in which a cell-containing solution plug was actively migrating back and forth several times by a finger-pressure induced receding meniscus. To optimize cell docking efficiency while minimizing unnecessary flooding in subsequent steps, circular microwells of various channel dimensions (4–24 µm diameter, 8 µm depth) along with different densities of cell solution (1.5–6.0 × 10<SUP>9</SUP> cells per mL) were tested. It was found that the microwells of 8 µm diameter and 8 µm depth allowed for an optimal docking efficiency (>90%) without notable flooding issues. For quantitative single-cell analysis, time-course (time interval 15 minute, for 2 hours) fluorescent images of the cells stimulated by mating pheromone were captured using computerized fluorescence microscope and the captured images were processed using a commercially available image processing software. Here, real-time cellular responses of the mating MAPK pathway were monitored at various concentrations (1 nM–100 µM) of mating pheromone at single-cell resolution, revealing that individual cells in the population showed non-uniform signaling response kinetics.</P> <P>Graphic Abstract</P><P>We present a simple yet robust microwell-based fluidic platform for capturing individual yeast cells at a density of ∼3900 cells per mm<SUP>2</SUP> and measuring time-course single-cell response on a large scale. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0lc00114g'> </P>

Real-Time PCR Cycle Threshold Values for the BRAFV600E Mutation in Papillary Thyroid Microcarcinoma May Be Associated With Central Lymph Node Metastasis: A Retrospective Study

Park, Vivian Y.,Kim, Eun-Kyung,Lee, Hye Sun,Moon, Hee Jung,Yoon, Jung Hyun,Kwak, Jin Young Williams & Wilkins Co 2015 Medicine Vol.94 No.28

ABSTRACT: Papillary thyroid microcarcinoma (PTMC) usually has excellent prognosis, but a small subset shows aggressive behavior. Although the B-Raf proto-oncogene, serine/threonine kinase (BRAF) mutation is the most common oncogenic alteration in PTMCs, it is frequently heterogeneously distributed within tumors. The aim of this study was to investigate the association of the BRAF mutation found in fine needle aspirates from PTMCs with known clinicopathologic prognostic factors, based on both its presence and a quantitative approach that uses cycle threshold (Ct) values obtained by a real-time PCR technique.The 460 PTMC patients were included, with 367 patients having the BRAF mutation. Clinicopathologic variables were compared between patients with and without the BRAF mutation. BRAF Ct values were compared according to clinicopathologic prognostic factors. Multivariate analyses were performed to evaluate factors predicting extrathyroidal extension and central and lateral lymph node metastasis (LNM). Each analysis used either the BRAF mutation status or the Ct value as an independent variable for all the study patients and the 367 BRAF-positive patients. Receiver-operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of BRAF Ct values in predicting central and lateral LNM.The BRAF mutation status was not associated with clinicopathologic prognostic factors among the 460 PTMC patients. Of the 367 BRAF-positive patients, Ct values were significantly lower in patients with central and lateral LNM (P < 0.001, P = 0.007). The Ct value was the only independent factor to predict central LNM (OR 0.918, P = 0.025). The area under the ROC curve (AUC) for diagnosing central LNM was 0.623 (sensitivity, 50.0%; specificity, 71.9%) and for diagnosing lateral LNM, it was 0.796 (sensitivity, 71.4%; specificity, 94.7%).In conclusion, real-time PCR Ct values for the BRAF mutation obtained from fine needle aspirates can be associated with central LNM in PTMC patients. Although BRAF Ct values did not reach statistical significance for predicting lateral LNM in our study, further validation through larger studies can be used to overcome any possible type-II errors. With further studies, Ct values for the BRAF mutation obtained from fine needle aspirates may have important implications for predicting both central and lateral LNM in patients with PTMCs.