경유 중 황 및 방향족화합물 조성에 따른 배출가스 특성연구 : 미량대기오염물질 중심으로

김종춘,서충열,임윤성,임철수,임재현,이종태,윤창완,이상일,김홍규,김상규,황춘식 한국대기환경학회 2008 한국대기환경학회 학술대회논문집 Vol.- No.-

연료 유형별 배출가스 특성연구

김종춘,서충열,곽순철,이종태,강대일,박정민,임윤성,황춘식 한국대기환경학회 2005 한국대기환경학회 학술대회논문집 Vol.- No.-

랫드에서 비스페놀 A의 발생독성에 대한 고려홍삼 물추출물의 효과

김종춘,임광현,서정은,위재준,남기열,정문구 한국독성학회 2001 Toxicological Research Vol.17 No.3

The present study was conducted to investigate the effects of Korean red ginseng water extract (KRGWE) on developmental toxicity caused by the environmental estrogen bisphenol A (BPA) in Sprague-Dawley rats. Fifty females successfully mated were randomly assigned to five experimental groups, i.e., group Ⅰ (vehicle control), group Ⅱ (BPA 1000mg/kg), group Ⅲ (KRGWE 400 mg/kg), group Ⅳ (BPA 1000mg/kg & KRGWE 200mg/kg), and group Ⅴ (BPA 1000mg/kg & KRGWE 400mg/kg). The test articles were administered by gavage to mated females from gestational days (GD) 1 through 20 (sperm vaginal lavage = day 0). All females were subjected to caesarean section on GD 21 and their fetuses were examined for external, visceral, and skeletal abnormalities. In the group Ⅱ, significant maternal toxic effects including suppressed body weight, decreased body weight gain during pregnancy, and reduced food consumption were observed in pregnant rats. The minimal developmental toxicity including fetal ossification delay was also found in fetuses. In addition, a tendency for increased pregnancy failure, increased pre- and postimplantation loss, and decreased fetal body weight was observed. However, no fetal morphological abnormalities were seen in surviving fetuses at a dose level of 1000mg BPA/kg. On the other hand, the maternal toxicity and developmental toxicity found in the groups Ⅳ and Ⅴ were comparable to those of the group Ⅱ. There were no adverse signs of either maternal toxicity or developmental toxicity in the group Ⅲ. These results showed that administration of BPA at a dose level of 1000mg/kg to pregnant rats resulted in significant maternal toxicity and minimal developmental toxicity, and that no protective effects on BPA-induced maternal toxicity and developmental toxicity were found by concomitant gavage dosing of KRGWE.

Cover Story - 봄철 황사대책

김종춘,Kim, Jong-Chun 한국방재협회 2012 방재저널 Vol.14 No.2

새만금 조하대 대형저서동물의 군집구조 변화

김종춘,한형섬,이승현 한국수산과학회 양식분과 2019 한국수산과학회 양식분과 학술대회 Vol.2019 No.5

Evaluation of the testicular toxicity caused by 2-bromopropane in rats

김종춘,이현숙,윤효인,정문구,Kim, Jong-choon,Lee, Hyun-sook,Yun, Hyo-in,Chung, Moon-koo The Korean Society of Veterinary Science 2000 大韓獸醫學會誌 Vol.40 No.2

최근 2-bromopropane(2-BP)이 사람과 실험동물에서 정소독성을 유발한다고 보고된 바 있다. 그러나 수컷 생식기계에 있어서 2-BP의 지연효과에 대해서는 세부적으로 조사된 바가 없다. 본 연구는 Sprague-Dawley 랫드에서 2-BP의 정소독성과 정자발생의 회복을 조사하기 위하여 수행하였다. 5주령의 수컷 랫드에게 2-BP를 1,000mg/kg 용량으로 4주간 반복투여하였고, 투여시작후 1, 2, 3, 4 및 12주째에 부검하였다. 정소독성의 평가는 병리조직학적인 질적평가와 생식기관 중량, 정자두부수 및 재생지수 등의 양적평가로 수행하였다. 시험결과 2-BP를 투여한 랫드에서는 체중과 정소 및 정소상체 중량이 대조군에 비해 시간의존적인 방식으로 억제 또는 감소하였다. 병리조직검사에서는 투여 1주째에 stage I~IV에서 정조세포와 stage VII~IX에서 세사전기 및 세사기의 정모세포가 현저하게 소실되었다. 정조세포는 투여 2주째에 모든 stage에서 광범위하게 소실되었으며, 정자발생주기가 진행됨에 따라 2, 3 및 4주째에는 접합기 정모세포, 비후기 정모세포 및 원형 정자세포가 전구세포의 결손에 의해 점진적으로 소실되었다. 지지세포의 기능적 이상을 암시하는 지지세포의 공포화와 정자세포 저류는 상기한 모든 시기에서 관찰되었다. 8주 회복후인 12주째에는 대부분의 곡세정관이 심하게 위축되어 지지세포만 관찰되었으며, 간질조직에서는 간질세포의 과형성이 인정되었다. 또한 2-BP에 의해 유발된 정소의 손상이 비가역적임을 암시해주는 정자두부와 재생지수의 현저한 감소가 관찰되었다. 상기결과는 랫드의 2-BP를 1,000mg/kg의 용량으로 4주간 반복투여하면 정조세포의 결손에 의해 점진적으로 생식세포가 감소하고 이로 인하여 장기적인 정소위축이 유발된다는 것을 암시해준다. It has been recently reported that 2-bromopropane (2-BP) induces male reproductive toxicity in both human and experimental animals. However, delayed effects of 2-BP on male reproductive system have not been investigated in detail. The present study was conducted to investigate the testicular toxicity of 2-BP and to determine the recovery of normal spermatogenesis in Sprague-Dawley rats. Male rats aged 5 weeks were administered 1,000mg/kg 2-BP by gavage daily for 4 weeks and sacrificed sequentially at 1, 2, 3, 4 and 12 weeks after initiation of 2-BP treatment. Testicular toxicity was evaluated qualitatively by histopathological examinations and quantitatively by reproductive organ weights, spermatid head count, and repopulation index. In the 2-BP treated rats, the body weights was significantly suppressed and the weights of testes and epididymides were also decreased in a time-dependent manner. On histopathological examination, spermatogonia in stages I-VI and preleptotene and leptotene spermatocytes in stages VII-IX were strongly depleted at 1 week of dosing. Spermatogonia were depleted extensively in all spermatogenic stages at 2 weeks. Continuing with the evolution of spermatogenic cycle, zygotene spermatocytes, pachytene spermatocytes, and round spermatids were sequentially depleted at 2, 3, and 4 weeks of dosing due to the depletion of their precursor cells. Vacuolization of Sertoli cells and spermatid retention were also observed at all time points, suggesting that 2-BP induced Sertoli cell dysfunction. At 12 weeks, after 8 weeks recovery, most of the tubules appeared severely atrophic and were lined by Sertoli cells only. Leydig cell hyperplasia in the interstitial tissue was also found. In addition, dramatic reductions in the number of spermatid heads and repopulation index were observed, indicating that 2-BP-induced testicular injury is irreversible. These results indicate that 4 weeks repeated-dose of 1,000mg/kg 2-BP results in a progressive germ cell loss due to the depletion of spermatogonia followed by long-term testicular atrophy in SD rats.

Single dose toxicity study of CKD-602, a new camptothecin anticancer agent, in Beagle dogs

김종춘,신동호,박승춘,손우찬,차신우,한정희,배주현,서정은,정문구,Kim, Jong-Choon,Shin, Dong-Ho,Park, Seung-Chun,Son, Woo-Chan,Cha, Shin-Woo,Han, Junghee,Bae, Joo-Hyun,Suh, Jeong-Eun,Chung, Moon-Koo The Korean Society of Veterinary Science 2004 大韓獸醫學會誌 Vol.44 No.1

The present study was carried out to investigate the potential acute toxicity of CKD-602 by a single intravenous dose in Beagle dogs. The test chemical was administered intravenously to male and female Beagle dogs at dose levels of 0.3, 0.5, or 2.5 mg/kg. Mortalities, clinical findings, and body weight changes were monitored for the 14-day period following the administration. At the end of 14-day observation period, all animals were sacrificed and complete gross postmortem examinations were performed. All males and females of the 2.5 mg/kg dose group were found dead between the fourth and seventh day after the injection. Treatment related clinical signs, including vomiting, anorexia, mucous stool, diarrhea, and no stool were observed. Decrease or suppression of body weight was observed in a dose-dependent manner. In autopsy, dark red discoloration of the gastrointestinal tract, atrophy of the thymus, paleness of the spleen, sporadic dark red spots of the lung and petechia of the heart were observed in dead animals of the 2.5 mg/kg dose group. There were no specific adverse effects on males and females of the 0.3 and 0.5 mg/kg dose groups, except for the transient clinical signs such as anorexia, vomiting, and mucus/no stool. On the basis of the results, it was concluded that a single intravenous injection of CKD-602 to Beagle dogs resulted in increased incidence of abnormal clinical signs and death, decreased body weight, and increased incidence of abnormal gross findings. The absolute toxic dose of this chemical was 2.5 mg/kg for both genders. The $LD_{50}$ value was 1.1 mg/kg (95% confidence limit not specified) for both genders. The no-observed-effect level (NOEL) was considered to be below 0.3 mg/kg for both genders.

Reader Preferences in Teacher-guided and Self-directed Extensive Reading Program

김종춘 사단법인 한국융합기술연구학회 2023 아시아태평양융합연구교류논문지 Vol.9 No.11

Extensive Reading (ER) is a pedagogical approach in second language (L2) education that has a strong foundation and is highly effective in fostering a passion for reading and enhancing reading proficiency. This study aimed to investigate the diverse landscape of ER, revealing the extensive range of genres, topics, and book selections it contains. The study examined a group of 83 nursing students in Seoul, who were divided into two groups: one receiving teacher guidance and the other engaging in self-directed learning. The program lasted for a duration of 15 weeks and focused on extensive reading training. The results indicated a strong preference for non-fiction literature, particularly in the field of Science, which aligns with the professional interests of the nursing students who took part in the study. The group that was supervised by the teacher demonstrated a wider range of subject study, particularly in the areas of Science, Social Studies, and History, highlighting the significance of having organized direction. On the other hand, the self-directed group exhibited a more equitable distribution of reading materials, encompassing both fiction and non-fiction genres. The observation may potentially indicate a correlation with their personal motivations and educational paths. Notable correlations were observed among specific subjects, suggesting a strong inclination towards interdisciplinary pursuits and the possibility of integrating disparate areas of knowledge. The books that are most frequently read tend to be focused on the subject of Science, while also maintaining a balanced reading level. This suggests that students have a preference for materials that are neither excessively simplistic nor excessively hard. Despite being somewhat overshadowed by factual content, narratives continue to maintain their attractiveness, therefore underlining their crucial position in the landscape of extensive reading settings. Furthermore, the study provides valuable perspectives on the reading habits of second language (L2) learners, emphasizing the ongoing popularity of narratives, the need of multidisciplinary education, and the delicate equilibrium between self-direction and instructional support. The aforementioned discoveries have the potential to impact instructional approaches, leading to a more effective integration of student needs and interests. Additionally, they provide a foundation for future investigations into the underlying motivations driving these preferences for reading materials.

수컷랫드에 있어서 새로운 안트라사이클린계 항암제 DA-125의 생식독성 연구

김종춘,김갑호,신호철,정문구 한국독성학회 1998 Toxicological Research Vol.14 No.2

The toxicity of DA-125. a new anthracycline anticancer agent, on the male reproductive system was studied in Sprague-Dawley rats. Forty male rats were rando$m\ell$y assigned to Jour groups with ten rats in each group and given single intraveneous doses of DA-125 at dose levels of 0. 12.5. 25. and 50 mg/kg body weight. On day 56 after treatment the animals were allowed to mate. and their male reproductive Junctions and organs were examined in detail. Copulated females were sacrificed on day 20 of gestation for examination of embryo-fetal development. One out of ten rats in the 50 mg/kg group died on day 12 after treatment. Clinical signs such as emaciation. sedation, anorexia. swelling. dark material around eye. alopecia. and diarrhea were observed in the 25 and/or 50 mg/kg groups. Reduction in the body weight gain. decrease in the absolute weights of testes. epididymis and seminal vesicles. and/or decrease in the number of testicular sperm heads were also found. Although histopathological changes such as atrophy of seminiferous tubules. loss or decrease of spermatogenic cells. exfoliation of spermatogenic cells. vacuolization of Sertoli cells. decrease of sperm. and/or increase of necrotic spermatogenic cells in epididymal ducts were observed. no adverse effects on the motility and morphology of epididymal sperm. copulation index. fertility index. and embryo-fetal development were detected in the 25 and 50 mg/kg groups. There were no evidences of male reproductive toxicity in the 12.5 mg/kg group. These results show that single intravenouse doses of DA-125 produce significant dose-related testicular atrophy. histopathological changes. and oligozoospermia in rats and $LD_{10}$ for DA-125 appears to be 50 mg/kg body weight.

Spatial and Temporal Distribution of Macrobenthos in Intertidal Hard Bottoms in Dokdo Island

김종춘,박강욱,유경동,정성용 한국환경생태학회 2015 한국환경생태학회지 Vol.29 No.2

This study was carried out to measure seasonal changes in the community structure and species composition of marobenthos in the intertidal area of Dokdo. The macrobenthos identified during this study was comprised of 36 species: predominately 25 species of mollusks(69.4 %), 6 species of arthropods(16.7 %), 3 species of echinodermata(8.3 %) and 1 species of cnidaria (5.6 %). The number of marobenthos species ranged from 27 in Spring to 33 in Autumn. In terms of the top 10 dominant species, there were 7 species of mollusks and 3 species of arthropods in the this study. After analyzing the bray-curtis similarity, it was divided into two large groups(A, B). Such group classification matched the SIMPROF(Similarity Profile Analysis) and the one-way ANOSIM(Analysis of similarities) analysis.