Clinical pathology in non-clinical safety assessment

Yongbaek Kim 한국실험동물학회 2017 한국실험동물학회 학술발표대회 논문집 Vol.2017 No.8

한일 어휘 비교 연구 - 『分類語彙表』을 이용해서 : 한일 어휘 비교 연구

이용백(Lee YongBaek) 한국외국어대학교 일본연구소 2004 日本硏究 Vol.22 No.-

Fourier Filter를 이용한 비전 기반 반도체 Wafer 결함 검출

권용백(Kwon Yongbaek),김양중(Yangjung Kim) 한국통신학회 2020 한국통신학회 학술대회논문집 Vol.2020 No.11

The Applicability of New Biological and Chemical Decontamination Technology to Nuclear Power Plant and Economic Analysis

YoungJu Son,Yongbaek Kim,Seung Yeop Lee,Junggyu Nam,JaeYeon Jung,Chang-Lak Kim 한국방사성폐기물학회 2019 한국방사성폐기물학회 학술논문요약집 Vol.2019 No.05

Ultrasonographic assessment of transitional cell carcinoma of the urinary bladder in dogs: a perspective of tumor size change

Kim, Seungji,Kim, Yongbaek,Kim, Wanhee,Choi, Mincheol,Yoon, Junghee The Korean Society of Veterinary Science 2017 大韓獸醫學會誌 Vol.57 No.3

Study purposes were to evaluate ultrasonographic characteristics of transitional cell carcinoma (TCC) and quantitate bladder tumor size in dogs. Heterogeneous mass, wall involvement, and broad-based attachment were significantly associated with TCC, but not prominently the trigone region. Mass size evaluation revealed a significant correlation between progressive disease (PD) in TCC patients with piroxicam therapy. Largest diameter of target lesion/body weight (cm/kg) ratio showed a high mean value in PD. A value > 0.3 was associated with PD with 83% sensitivity and 66% specificity. The results suggest that ultrasonography can provide evidence for diagnosing and predicting a prognosis for TCC.

Hepatic extraskeletal osteosarcoma with systemic metastasis in a dog

Johnson, Crystal,Kim, Yongbaek The Korean Society of Veterinary Science 2013 大韓獸醫學會誌 Vol.53 No.1

A ten-year-old dog was presented with pancreatitis and increased hepatic enzymes. On necropsy a large firm mass was observed in the liver extending to the gall bladder. Smaller masses with similar texture were found in multiple organs including lung, stomach, pancreas, lymph nodes, omentum, and mesentery. Neoplastic cells were spindle shaped with prominent osteoid production and occasional trabeculae of woven bone. Tumor cell emboli were observed in the blood vessels and lymphatics of the omentum and stomach. Hepatic osteosarcoma with systemic metastasis is very rare and may serve to broaden the diagnostic spectrum of hepatic and pancreatic diseases in dogs.

Pathology-based Evaluation of Chemical Toxicity in the National Toxicology Program and Development of Toxicological Testing Methods for Human Risk Assessment : Carcinogenicity Studies of Dioxin and Dioxin-like Chemicals

Byung-IL Yoon,Yongbaek Kim,Beom Seok Han,Boo-Hyon Kang 한국실험동물학회 2009 Laboratory Animal Research Vol.25 No.4

본 연구에서는 NTP에서 수행한 다이옥신 및 다이옥신류 화학물질들의 발암성시험으로부터 얻어진 병리결과를 토대로 어떠한 기준과 근거에 의해서 발암성을 정의하는 지에 대하여 예를 들어 설명하였다. 그러나, 본문에서도 언급하였듯이 동물실험에서 발암성이 음성으로 나왔다고 해서 발암물질이 아니라는 의미가 아니며, 발암성이 있다고 하는 것은 해당물질이 사람에 노출되면 종양발생과 관련하여 해로울 수 있다는 것을 나타낸다. NTP에서는 병리결과에 근거하여 5가지의 분류기준에 따라 시험물질들의 발암성을 평가하고 있으나, 보다 신뢰성 있는 결론을 도출하기 위하여 물질의 독성기전에 기초한 실험들을 발암성시험에서 함께 병행하고 있다. 다이옥신과 유사물질들의 독성이 AhR의 매개로 일어나며, CYP1A1과 CYP1A2 간대사효소의 발현과 깊이 연관이 있기 때문에 발암성시험기간 동안 효소의 활성도를 함께 측정하였으며, 간세포 증식성 검사, 갑상샘호르몬 농도측정도 수행하였다. 즉, 발암성평가시험의 경우 일반적으로 병리검사결과가 판단의 중요한 역할을 하지만, 물질의 작용기전에 기초한 가능한 많은 정보를 획득하여 분석함으로써 보다 올바르고 정확한 결론을 내릴 수 있도록 노력해야 한다. 발암성평가는 병리결과에 근거하여 5가지의 판단기준에 따라 발암성을 분류하는데, 발암성시험에 있어 결론을 내릴 때 고려해야 할 중요한 사항들을 요약하면, 1) 실험의 계획과 수행이 잘 이루어졌는가, 2) 자연적으로도 자주 관찰되는 종양과 드문 종양의 발생, 3) 양성종양에서 악성종양으로, 전암병변에서 종양성병변으로의 진행된다는 증거 또는 이론이 있는가, 4) 일부 양성종양은 퇴축되는 반면, 동일한 형태학적 특성을 가진 일부 양성종양은 악성으로 진행되는데, 형태학적으로 이것을 구분하는 것은 불가능하다. 따라서, 양성이 악성으로 진행될 수 있는 가능성이 있다고 한다면 양성종양이 악성종양으로 진행된다고 가정한다. 5) 동일한 장기 또는 조직에서 진행의 연속성을 가지는 경우 양성과 악성종양의 발생을 합하는 것, 즉, 양성과 악성을 따로 떼어 보면, 대조군과 별 차이가 없어 보이지만, 합하게 되면 뚜렷한 증가추세와 통계적으로도 유의차가 나타나는 경우가 있다. 6) 특정부위에서 발생한 종양의 multiplicity, 7) 전이(metastasis), 8) 종양이 발생한 동일한 장기에서의 과형성병변의 발생, 또는 다른 종 또는 성에서 수행한 실험에서 나타난 과형성병변의 발생양상, 9) 용량상관성 여부, 10) 발생한 종양의 통계적으로 유의차 있는 증가, 11) 특정 종양의 대조군에서의 발생정도와 종양발생정도의 개체차이, 12) 생존률을 고려한 분석과 의양성(false positive) 및 의음성(false negative) 가능성, 13) 시험물질의 화학적 구조와 활성과의 상호관련성(structure-activity correlation), 14) 유전독성여부(genetic toxicity) 등이다. NTP 시험결과보고서는 내용이 광범위하고 많아 본 연구에서 모든 것을 다룰 수는 없었으나, 병리결과를 토대로 다이옥신과 유사물질들의 발암성평가결과를 해석하고 평가하는 기준과 근거들을 예를 들어 설명 고찰하였다. Pathological data sets are critical for evaluation of carcinogenicity of chemicals in the preclinical studies using laboratory animals. Proper diagnosis and interpretation of non-neoplastic and neoplastic lesions, no matter what they are spontaneously developed or chemically induced, are prerequisite for determination of chemical carcinogenicity. The pathology-based criteria have been developed to evaluate the carcinogenic activity of chemicals; two positive results (clear evidence and some evidence), one uncertain finding (equivocal evidence), no observable effect (no evidence), and inadequate study. However, there are lots of things that we need to consider before determination of carcinogenic activity of chemicals such as adequacy of the experimental design and conduct, common and uncommon neoplasia, progression from benign to malignant neoplasia as well as from preneoplastic to neoplastic lesions, combining benign and malignant tumor incidence in the same organs, multiplicity in site-specific neoplasia, dose relationship, statistical significance of the observed tumor increase, concurrent control tumor incidences as well as historical control rate for a specific neoplasm, etc. In the present study, we introduce the carcinogenicity studies of dioxin and dioxin-like chemicals which had been performed as National Toxicology Program (NTP) in the USA for years, and discuss the pathology data-based approaching strategy for determination of carcinogenic activity of chemicals.

Gross Morphological Features of the Organ Surface Primo-Vascular System Revealed by Hemacolor Staining

Lim, Chae Jeong,Yoo, Jong-Hyun,Kim, Yongbaek,Lee, So Yeong,Ryu, Pan Dong Hindawi Publishing Corporation 2013 Evidence-based Complementary and Alternative Medic Vol.2013 No.-

<P>The primo-vascular system (PVS), which consists of primo-vessels (PVs) and primo-nodes (PNs), is a novel thread-like structure identified in many animal species. Various observational methods have been used to clarify its anatomical properties. Here, we used Hemacolor staining to examine the gross morphology of organ-surface PVS in rats. We observed a sinus structure (20–50 <I><I>μ</I></I>m) with a remarkably low cellularity within PNs and PVs and several lines of ductules (3–5 <I><I>μ</I></I>m) filled with single cells or granules (<I>~</I>1 <I><I>μ</I></I>m) in PV. Both sinuses and ductules were linearly aligned along the longitudinal axis of the PVS. Such morphology of the PVS was further confirmed by acridine orange staining. In PN slices, there was a honeycomb-like structure containing the granules with pentagonal lumens (<I>~</I>10 <I><I>μ</I></I>m). Both PVs and PNs were densely filled with WBCs, RBCs, and putative mast cells (MCs), which were 90.3%, 5.9%, and 3.8% of the cell population, respectively. Granules in putative MCs showed spontaneous vibrating movements. In conclusion, the results show that Hemacolor, a simple and rapid staining system, can reveal the gross morphological features reported previously. Our findings may help to elucidate the structure and function of the PVS in normal and disease states in future studies.</P>

육군 병사의 의무부대 의료서비스 경험, 재이용 의도 및 일차의료 질 평가

백서영 ( Baek Seoyoung ),최용백 ( Choi Yongbaek ),황신우 ( Hwang Sinwoo ),조순영 ( Joe Seunyoung ) 국군간호사관학교 군건강정책연구소 2021 군진간호연구 Vol.39 No.1

Purpose: The purpose of this study was to identify the relationships among patient experience, revisit intention, and assessment of primary health care of military division medical facilities. Methods: This study was a cross-sectional survey, and investigated a total of 198 soldiers who visited medical facilities. Data were collected from August to December 2020 using the structured questionnaires. Results: The average score of patient experience was 86.40±11.83, revisit intention 5.98±1.15, and assessment of primary health care 84.63±12.88 out of 100 each. There was significantly positive correlation between patient experience and revisit intention (r=.66, p<.001), patient experience and assessment of primary health care (r=.65, p<.001), and revisit intention and assessment of primary health care (r=.68, p<.001). Conclusion: This study identified the importance of virtuous cycle among patient experience, revisit intention and assessment of primary health care. The result is expected to be used as a evidence for developing policy and strategies to improve quality of primary health care in the military.

Hydrogen Peroxide Promotes Epithelial to Mesenchymal Transition and Stemness in Human Malignant Mesothelioma Cells

Kim, Myung-Chul,Cui, Feng-Ji,Kim, Yongbaek Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

Reactive oxygen species (ROS) are known to promote mesothelial carcinogenesis that is closely associated with asbestos fibers and inflammation. Epithelial to mesenchymal cell transition (EMT) is an important process involved in the progression of tumors, providing cancer cells with aggressiveness. The present study was performed to determine if EMT is induced by $H_2O_2$ in human malignant mesothelioma (HMM) cells. Cultured HMM cells were treated with $H_2O_2$, followed by measuring expression levels of EMT-related genes and proteins. Immunohistochemically, TWIST1 expression was confined to sarcomatous cells in HMM tissues, but not in epithelioid cells. Treatment of HMM cells with $H_2O_2$ promoted EMT, as indicated by increased expression levels of vimentin, SLUG and TWIST1, and decreased E-cadherin expression. Expression of stemness genes such as OCT4, SOX2 and NANOG was also significantly increased by treatment of HMM cells with $H_2O_2$. Alteration of these genes was mediated via activation of hypoxia inducible factor 1 alpha (HIF-$1{\alpha}$) and transforming growth factor beta 1 (TGF-${\beta}1$). Considering that treatment with $H_2O_2$ results in excess ROS, the present study suggests that oxidative stress may play a critical role in HMM carcinogenesis by promoting EMT processes and enhancing the expression of stemness genes.