• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 춘계학술대회
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• pp.194-194
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• 2003

The International Agency for Research on Cancer (IARC, 1989) has classified whole diesel exhaust as probably carcinogenic to humans. Diesel exhaust particulate matter (DPM) adsorbs different chemical substances including PAHs and nitroarenes. DPM is emphasized because it is a major component of diesel exhaust, it is suspected of contributing to a health hazard. Diesel exhaust is a complex mixture of carbon particles and associated organics and inorganics, and it is not known what fraction or combination of fractions cause the health effects [cancer effects, noncancer effects (respiratory tract irritation/inflammation and changes in lung function)] that have been observed with exposure to diesel exhaust. In order to identify which chemical classes are responsible for the majority of the observed biological activities, we performed a particular biological/chemical analysis. Respirable particulate matter (PM2.5: <2.5mm) was collected from diesel engine exhaust using a high-volume sampler equipped with a cascade impactor. Particulate oganic matter was extracted by the dichloromethane/sonication method and the crude extract was fractionated according to EPA recommended procedure into seven fractions by acid-base partitioning and silica gel column chromatography. We examined genotoxic potentials of diesel exhaust particulate matter using novel genotoxicity tests, which are rapid, simple and sensitive methods for assessing DNA-damage at the DNA and chromosomal level (comet assay, in vitro MN test and Ames test). Higher genotoxic potency was observed in non polar fractions and several PAHs were detected by GC-MS, such as 1,2,5,6 dibenzanthracene, chrysene, 1,2-benzanthracene, phenanthrene and fluoranthene.

• 한국환경보건학회지
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• 제50권2호
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• pp.113-124
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• 2024

Background: The increasing need to minimize animal testing has sparked interest in alternative methods with more humane, cost-effective, and time-saving attributes. In particular, in silico-based computational toxicology is gaining prominence. Adverse outcome pathway (AOP) is a biological map depicting toxicological mechanisms, composed of molecular initiating events (MIEs), key events (KEs), and adverse outcomes (AOs). To understand toxicological mechanisms, predictive models are essential for AOP components in computational toxicology, including molecular structures. Objectives: This study reviewed the literature and investigated previous research cases related to AOP and in silico methodologies. We describe the results obtained from the analysis, including predictive techniques and approaches that can be used for future in silico-based alternative methods to animal testing using AOP. Methods: We analyzed in silico methods and databases used in the literature to identify trends in research on in silico prediction models. Results: We reviewed 26 studies related to AOP and in silico methodologies. The ToxCast/Tox21 database was commonly used for toxicity studies, and MIE was the most frequently used predictive factor among the AOP components. Machine learning was most widely used among prediction techniques, and various in silico methods, such as deep learning, molecular docking, and molecular dynamics, were also utilized. Conclusions: We analyzed the current research trends regarding in silico-based alternative methods for animal testing using AOPs. Developing predictive techniques that reflect toxicological mechanisms will be essential to replace animal testing with in silico methods. In the future, since the applicability of various predictive techniques is increasing, it will be necessary to continue monitoring the trend of predictive techniques and in silico-based approaches.

• 한국가스학회지
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• 제16권6호
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• pp.80-86
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• 2012

주요 설비를 설치 이전하거나 구조부분을 변경하기 전에 안전성을 심사 확인하여 이들에 대한 근원적인 안전성을 확보하기 위해 고용노동부는 제조업 유해 위험방지계획서 제도를 1982년부터 시행하고 있다. 그러나 주요 산업재해를 발생시키고 있는 취약업종이 제도 적용 대상에서 제외되어 근원적인 재해예방에 한계가 있다. 이러한 제도의 한계를 해결하고자 유해 위험설비의 대상업종 8개를 선정하여 이에 따른 비용편익을 분석하였다. 비용편익 분석방법은 정책 실행수단을 선택하거나 정책의 기대효과를 추정하기 위한 가장 기초적인 분석방법으로, 규제 실행의 정당성을 입증해 주는 기본 자료로서 활용하였다. 분석 결과 1차 금속 제조업의 편익이 가장 크게 나타났으며 다음으로 자동차 및 트레일러 제조업, 기타 제품 제조업, 기타 기계 및 장비제조업, 목재 및 나무제품 제조업, 고무제품 및 플라스틱 제조업, 식료품 제조업, 가구 제조업 순으로 높게 나타났다. 따라서 국가경쟁력을 강화하며 근로자의 신체와 생명을 보호하고, 재해나 사망으로 발생되는 사회적 비용을 저감시켜 국가 전체의 후생수준을 증대시키기 위해 8개 업종으로 유해 위험방지계획서의 작성을 확대할 필요가 있다.

• Radiation Oncology Journal
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• 제37권3호
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• pp.185-192
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• 2019

Purpose: The effectiveness of thoracic radiation therapy (TRT) in extensive-stage small cell lung cancer (ES-SCLC) patients is increasingly reported, but there is no definite consensus on its application. The aim of this study was to identify factors associated with better outcomes of TRT among patients with ES-SCLC, focusing on whether a higher TRT dose could improve treatment outcome. Materials and Methods: The medical records of 85 patients with ES-SCLC who received TRT between January 2008 and June 2017 were retrospectively reviewed. Eligibility criteria were a biological effective dose with α/β = 10 (BED) higher than 30 Gy₁₀ and completion of planned radiotherapy. Results: During a median follow-up of 5.3 months, 68 patients (80.0%) experienced disease progression. In univariate analysis, a BED >50 Gy₁₀ was a significant prognostic factor for overall survival (OS; 40.8% vs. 12.5%, p = 0.006), progression-free survival (PFS; 15.9% vs. 9.6%, p = 0.004), and intrathoracic PFS (IT-PFS; 39.3% vs. 20.5%, p = 0.004) at 1 year. In multivariate analysis, a BED >50 Gy₁₀ remained a significant prognostic factor for OS (hazard ratio [HR] = 0.502; 95% confidence interval [CI], 0.287-0.876; p = 0.015), PFS (HR = 0.453; 95% CI, 0.265-0.773; p = 0.004), and IT-PFS (HR = 0.331; 95% CI, 0.171-0.641; p = 0.001). Response to the last chemotherapy was also associated with better OS in both univariate and multivariate analysis. Conclusion: A TRT dose of BED >50 Gy₁₀ may be beneficial for patients with ES-SCLC. Further studies are needed to select patients who will most benefit from high-dose TRT.

• 대한의용생체공학회:의공학회지
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• 제18권3호
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• pp.233-241
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• 1997

The research on chromosomes is very significant in cytogenetics since genes of the chromosomes control revelation of the inheritance plasma. The human chromosome analysis is widely used to study leukemia, malignancy, radiation hazard, and mutagen dosimetry as well as various congenital anomalies such as Down's, Klinefelter's, Edward's, and Patau's syndrome. The framing and analysis of the chromosome karyogram, which requires specific cytogenetic knowledge is most important in this field. Many researches on automated chromosome karyotype analysis methods have been carried out, some of which produced commercial systems. However, there still remains much room to improve the accuracy of chromosome classification and to reduce the processing time in real clinic environments. In this paper, we proposed a hierarchical artificial neural network(HANN) to classify the chromosome karyotype. We extracted three or four chromosome morphological feature parameters such as centromeric index, relative length ratio, relative area ratio, and chromosome length by preprocessing from ten human chromosome images. The feature parameters of five human chromosome images were used to learn HANN and the rest of them were used to classify the chromosome images. The experiment results show that the chromosome classification error is reduced much more than that of the other researchers using less feature parameters.

• 대한의생명과학회지
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• 제28권4호
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• pp.260-275
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• 2022

Sterile alpha motif (SAM) domains bind to various proteins, lipids, and RNAs. However, these domains have not yet been analyzed as prognostic biomarkers. In this study, SAM domain containing 13 (SAMD13), a member of the SAM domain, was evaluated to identify a novel prognostic biomarker in various human cancers, including hepatocellular carcinoma (HCC). Moreover, we identified a correlation between SAMD13 expression and immune cell infiltration in HCC. We performed bioinformatics analysis using online databases, such as Tumor Immune Estimation Resource, UALCAN, Kaplan-Meier plotter, LinkedOmics, and Gene Expression Profiling Interactive Analysis2. SAMD13 expression in HCC samples was significantly higher than that in normal liver tissue; additionally, SAMD13 was higher in primary tumors, various stages of cancer and grades of tumor, and status of nodal metastasis. Higher SAMD13 expression was also associated with poorer prognosis. SAMD13 expression positively correlated with CD8+ T cells, CD4+ T cells, B cells, neutrophils, macrophages, and dendritic cells. In the analysis of SAMD13 co-expression networks, positively related genes of SAMD13 were associated with a high hazard ratio in different types of cancer, including HCC. In biological function of SAMD13, SAMD13 mainly include spliceosome, ribosome biogenesis in eukaryote, ribosome, etc. These results suggest that SAMD13 may serve as a novel prognostic biomarker for HCC diagnosis and provide novel insights into tumor immunology in HCC.

• 생물정신의학
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• 제28권1호
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• pp.13-22
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• 2021

Objectives Despite growing attention to anxiety in bipolar disorder (BD), little research has assessed anxiety symptoms in the course of BD. The current prospective follow-up study examines the influence of subjectively and objectively measured anxiety symptoms on the course of BD. Methods A total of 49 patients with BD were followed-up prospectively for average of one year at an average of four months interval. The Korean version of the Beck Anxiety Inventory (K-BAI), the Hamilton Anxiety Rating Scale, heart rate variability (HRV) were used to measure anxiety subjectively, objectively and physiologically. Participants were divided into high and low anxiety groups based on their K-BAI scores. Kaplan-Meier survival analysis was performed to compare the recurrence of mood episode, suicide attempt, emergency room visit, and psychiatric hospitalization between two groups. Mediators were investigated with Cox proportional hazards models. Results Compared to the low anxiety group, the high anxiety group reported significantly higher impulsiveness (p = 0.016) and lower high frequency component on HRV (p = 0.007) after controlling for severity of BD. Regarding survival analysis, the high anxiety group showed hastened depressive episode recurrence (p = 0.048) and suicidal ideation was the mediator of the hazard ratio (HR) 1.089 (p = 0.029) in the Cox model. Moreover, the high anxiety group showed a tendency of accelerated suicide attempt (p = 0.12) and impulsivity was the risk factor of suicide attempt (HR = 1.089, p = 0.036). Conclusions This interim analysis of prospective study suggests that high anxiety level in BD may anticipate unfavorable course. Further studies are needed to understand the multifactorial mechanism of anxious bipolar patients.

• 한국식품과학회지
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• 제36권6호
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• pp.1032-1040
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• 2004

생식은 건강 지향적 식생활 양상의 변화로 최근 소비가 급증하고 있으나, 업체의 영세성에 따른 위생관리가 미비하며 제조공정의 표준화가 되어 있지 않아 안전성 문제가 대두되고 있다. 본 연구는 생식의 위생적 생산을 위한 생식 생산 공정의 HACCP 일반모델을 개발을 위해 생식 원료의 세척에서부터 최종제품 포장까지 각 제조공정별로 생물학적, 물리적, 화학적 요인의 위해요인을 분석하고 중요관리점(CCPs)를 설정하고자 하였다. 원료의 세척부터 최종제품 포장까지 각 제조공정별로 생물학적, 물리적, 화학적 요인의 위해요인을 분석하였다. 생식원료의 오염수준은 $2.82-8.23\;{\log}_{10}\;CFU/g$의 일반세균수가 검출되었으며, 또한 $1.40-6.57\;{\log}_{10}\;CFU/g$의 coliforms이 검출되었다. 최종제품 중 일반세균수는 $1.51-7.40\;{\log}_{10}\;CFU/g$이 검출되었다. 제조공정 중 미생물 수 변화는 모든 원료에서 공정별로 유사한 패턴을 보여 주었는데 세척과 동결건조공정에서 일반세균수와 대장균군은 감소하였다. 물리적 요인인 이물 혼입과 화학적 요인인 수분함량의 변화가 위해 요인으로 분석되었다. 생식의 제조공정 중 CCP는 미생물 감소를 위한 세척 단계, 수분 관리를 위한 건조단계, 그리고 금속 등 이물질의 혼입단계로 설정되었다.

• 한국식품위생안전성학회지
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• 제24권2호
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• pp.174-181
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• 2009

생활수준의 향상으로 건강과 웰빙에 대한 관심이 늘면서 즉석섭취(ready-to-eat) 농산물의 수요가 증가하고 있다. 이들 농산물중 파프리카, 딸기, 토마토 등은 우리나라의 대표적인 수출 농산물로서 안전성 확보가 중요하다. 본 연구는 대전시내 2개 백화점과 2개 대형할인점에서 유통 중인 파프리카, 딸기 및 토마토를 대상으로 총호기성균, 대장균군, 식중독 유발 세균 및 기생충의 오염 수준을 배지 배양법, multiplex PCR, 상업용키트 및 현미경으로 조사하였으며, 또한 세척방법별 세균 감소율을 평가하였다. 유통중인 파프리카, 딸기 및 토마토의 평균 총호기성균 수는 $1.3{\times}10^4{\sim}1.8{\times}10^5$CFU/g, 평균 대장균군의 수는 $1.4{\times}10^3{\sim}9.6{\times}10^3$CFU/g 범위이었으며, 세균 오염 정도는 매장별로 유의한 차이를 보이지 않았다. 총호기성균 및 대장균군의 오염 정도는 딸기에서 가장 높았으며, 딸기에서 미확인 기생충 충란이 발견되었다. 조사한 농산물에서 가장 흔히 분리되는 세균은 Enterobacter cloacae 이었으며, 식중독 유발 세균중 Staphylococcus aureus가 딸기에서 발견 되었으나 그 외의 식중독 유발 세균은 분리되지 않았다. 딸기를 대상으로 세척방법별 세균 감소율을 조사한 결과 수돗물로 5회이상 세척시 일반세균의 80%이상을 제거할 수 있었으며 야채용 세제를 사용하거나 초음파 세척시 세균 감소율이 증가하였다. 이상의 결과로 보아, 파프리카, 딸기 및 토마토의 세균 및 기생충의 오염 정도를 조사한 결과 딸기에서 가장 많은 생물학적 오염을 보였으며, 이들 농산물들의 생물학적 오염 정도는 구입 매장별로 유의한 차이를 보이지 않았다.

• 한국환경보건학회지
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• 제43권5호
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• pp.360-369
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• 2017

Objectives: The organizational culture of small-scale enterprises is influenced by a lack of awareness of industrial accidents and a business-oriented culture. Therefore, the purpose of this study is to establish a correlation between chemical awareness and worker safety, which is the reason why a company's safety environment is responsible for human factor accidents. Methods: The research model established the organizational culture, human relationships, organizational relationships, workplace culture, safety climate, and safety parameters, all of which affect the perception of chemical substances, then established safety rankings, communication, safety regulations, and safety support. Results: In order to derive the results of this study, the satisfaction level was mostly derived from the degree of engagement (+) depending on the number of years worked, in the hierarchical regression analysis. During work with chemicals, the number of years spent on the level of the service was determined by the influence of the chemical (-). Based on this company, the occurrence of chemical accidents caused by chemical materials was felt to be felt at the risk of causing the hazard to be felt, the absence of physical damage was excluded from the variables. The other variables detected in the variables were $62.8{\pm}24.4$. Conclusion: As a result, it is necessary to develop a statistical model for the verification of the hierarchical regression analysis, and the relationship between safety and awareness of the dangers of chemicals and biological agents requires periodic safety training. Job satisfaction was found to be higher if the level of awareness was sufficient.