정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

콩 단백 성분 및 연령이 암컷 흰쥐의 혈장 지질 농도와 인지질 지방산 패턴에 미치는 영향

정은정(Eun-Jung Chung),김수연(Soo-Yeon Kim),김지영(Ji-Young Kim),안지영(Ji-Young Ahn),박정화(Jung-Wha Park),차명화(Myung-Hwa Cha),이양자(Yang-Cha Lee Kim) 한국식품영양과학회 2003 한국식품영양과학회지 Vol.32 No.2

혈중 지질농도는 식이단백질 종류보다는 연령의 영향을 많이 받아, young군보다 old군의 총 콜레스테롤, TG, HDL-콜레스테롤, LDL+VLDL-콜레스테롤 및 AI 모두 높았다. 한편 콩 단백질군에서 HDL-콜레스테롤 수준이 증가하고, LDL+VLDL-콜레스테롤와 AI는 감소하여, 심혈관질환에 대한 콩 단백질의 유익한 효과를 확인할 수 있었다. 식이단백질에 의해 유의한 영향을 받은 혈장 인지질의 지방산조성중 22:0, 18:1ω9, ∑MUFA 조성은 카제인군에서 콩 단백질군 보다 높았으며, 반대로 ∑SFA 조성은 카제인군에서 낮았다. 연령에 의해 혈장 인지질 지방산 조성에 있어 유의한 차이를 보인 지방산 중 22:0, 18:1ω9, 22:1, 18:3ω3 및 22:4ω6는 young군에서 높은 반면에, 22:6ω3, ∑ω3, 18:2ω6, 20:4ω6, ∑ω6 및 ∑PUFA의 조성비율은 old군에서 높게 나타났다. 이와 같이 식이 단백질의 종류보다 연령의 영향력이 더 많이 나타난 것은 혈중 콜레스테롤 수준이 식이 단백질보다는 연령의 영향을 더 크게 받았기 때문으로 생각된다. 혈장 인지질 지방산의 대사지표 중 Δ7-desaturation index(16:0⇒16:1ω7)와 Δ9-desaturation index(18:0⇒18:1ω9)가 식이 단백질의 영향을 받아 카제인군에 비해 콩 단백질군에서 유의하게 낮았다. Δ7- 및 Δ9-desaturation index만이 식이 단백질의 영향을 받은 것은 식이 단백질보다 desaturase 활성에 더 큰 영향력을 미치는 콜레스테롤이 식이에 첨가되었기 때문이라 생각된다. Δ-4 desaturation index (22:4ω6⇒22:5ω6)는 young군에 비해 old군에서 높았으며, elongation index(20:4 ω6⇒22:4ω6)는 old군에서 낮았다. 대부분의 elongation과 desaturation 단계는 연령에 따라 유의한 차이를 보이지 못하였으나, ω3계 지방산의 전체적인 elongation-desaturation 단계를 나타내는 ∑products-fatty acid(ω3)/α-LNA(ω3) 비율이 old군에서 young군보다 유의하게 높아, 연령에 따른 PUFA 대사의 변화가 관찰되었다. 이상에서와 같이, 콩 단백질의 섭취로 흰쥐 혈장 인지질의 ∑MUFA 조성은 낮고 ∑SFA 조성은 높아 다른 지질 강화성분의 섭취와 유사한 결과를 나타내었다. 혈중 콜레스테롤 수준이 높은 old군에서 체내 막조직의 유동성을 유지하기 위해 PUFA의 합성 특히 ω3계 지방산의 elongation-desaturation이 증가하여 총 PUFA 조성이 young군보다 높았다. 연구결과로 이소플라본을 포함한 콩 단백질의 혈중 지질저하 기전에 대해 체계적인 설명은할 수 없지만, 콩 단백질이 혈장 지방산의 조성을 변화시킴으로써 간접적으로 심혈관계 질환에 대해 유익한 효과를 미침을 알 수 있었다. 한편, 이러한 혈관의 건강과 관련된 콩의 유익한 효과는 이소플라본과 같은 콩의 특정 성분의 단독효과라기보다는 콩 단백질과의 복합효과에 의한 것이라는 주장은 매우 설득력 있다고 생각된다. Effects of soy protein concentrate (SPC) containing isoflavone and casein diets on plasma phospholipid (PLs)-fatty acid patterns were investigated in 7- & 40- wk old female rats. Diets containing 16% SPC (soy/young: SY, soy/old: SO) and casein (casein/young: CY, casein/ old: CO) supplemented with 0.5% cholesterol were fed for 4 wks. Fatty acid compositions of plasma PLs were determined by TLC and GLC. Compared to the dietary protein effects, age effects on serum lipids were more profound. The levels of total cholesterol (Chol.), triglyceride, HDL-Chol., (LDL+VLDL)-Chol. and atherogenic index (AI) were higher in older groups (OC & OS) than younger groups (YC & YS). Soy groups had higher HDL-Chol. level and lower (LDL+VLDL)-Chol. and AI, compared with casein groups. The compositions of C22:0, C18:1ω9 and sum of MUFA in plasma PLs were significantly higher in casein group (CY & CO) than soy group (SY & SO), but those of sum of SFA were higher in soy group. The compositions of C22:0, C18:1ω9, C22:1, C18:3ω3 and C22:4ω6 were higher and those of C22:6ω3, sum ofω3, C18:2ω6 C20:4ω6, sum ofω6 and sum of PUFA were lower in plasma PLs of younger rats. The average P/S and ω3/ω6 ratio in older group was higher. The Δ-7 desaturation index (16:0⇒16:1ω7) and Δ-9 desaturation index (18:0⇒18 : 1ω9) were lower in soy group than casein group, while Δ-6 and Δ-5 desaturation index were not affected by dietary protein. The Δ-4 desaturation index (22:4ω6⇒22:5ω6) were higher and, elongation index (20:4ω6⇒22:4ω6) were lower in older group. The ratio of the products of ω3 fatty acid series/precursor of ω3 fatty acid series (C18:3) was significantly higher in older group, which in- dicated that age affected the plasma PUFA metabolism. On the other hand, older rats had higher serum cholesterol level compared with younger rats. Taken together, these changes in fatty acid composition might cause minimal changes in the membrane fluidity induced by the increase serum cholesterol level.

Hepatic Cirrhosis Occurring in a Young Woodchuck(Marmota monax) Due to Vertical Transmission of Woodchuck Hepatitis Virus(WHV)

Kyu-shik Jeong,정원일,Jae-yong Chung,Mi-young An,Chae-yong Jung,Gyoung-jae Lee,Jong-soo Kang,Byeong-cheol Kang,Young-heun Jee,Bruce H Williams,Young-oh Kwon,Da-hee Jeong 대한수의학회 2003 Journal of Veterinary Science Vol.4 No.2

Cirrhosis Occurring in a Young Woodchuck (Marmota monax) Due to Vertical Transmission of Woodchuck Hepatitis Virus (WHV)Da-hee Jeong, Won-il Jeong, Jae-yong Chung, Mi-young An, Chae-yong Jung, Gyoung-jae Lee1, Jong-soo Kang1, Byeong-cheol Kang2, Young-heun Jee3, Bruce H Williams4, Young-oh Kwon5 and Kyu-shik Jeong*College of Veterinary Medicine, Kyungpook National University, Daegu 702-701, Korea1Shinwon Scientific Co., LTD, Research Institute, Suwon, Korea2Clinical Research Institute, Seoul National University, Seoul 110-744, Korea3College of Veterinary Medicine, Jeju National University, Jeju 690-756, Korea

고령자 급성 췌장염의 임상적 고찰

이진헌,강진경,박인서,송건훈,정재복,백용한,송시영,서정훈 대한소화기학회 1998 대한소화기학회지 Vol.32 No.3

Background/Aims: Inflammatory diseasas of the pancreas are not uncommon. The advanced age is one of the significant factors in assessing the severity of acute pancreatitis. It has been shown that the biliary tract disease is a more frequent cause of acute pancreatitis in the elderly than in the young. With the increased life span, the elderly are comprising a large proportion of the population. As a result, physicians are more often being faced with acute pancreatitis in the elderly. The purpose af this study was to evaluate clinical features of acute panereatitis in the elderly. Methods: A total of 188 patients with acute pancreatitis were reviewed. We investigated the differences of clinical characteristics between the elderly patients aged over 60 and the young patients aged under 60. Results: The sex distribution showed male preponderance in the young patients (M:F=2.4:1), but was nearly equal in the elderly patients (M:F=1.1:1). The most common cause of acute pancreatitis in the elderly was biliary tract disease (52.5%), while alcohol abuse was the most common cause in the young patients (38.8%), Local complications of acute pancreatitis, such as psuedocyst, necrosis, abscesses were not differently shown between the elderly (16.9%) and the young (20.2%) patients. Systemic complications including acute puhnonary failure occurred more frequently in the elderly patients than the young patients. The mortality rate of the elderly patients (5.1%) was not significantly different from that of the young patients (3.1%). Conclusions: To detect correctable underlying bihary tract diseases the elderly patients with acute pancreatitis should be completely investigated using endoscopic retrograde cholangiopancreatography (ERCP). In addition, the patient should be closely monitored for the development of the systemic complications during the disease process.

Increased 11β-hydroxysteroid dehydrogenase type 1 contributes to barrier dysfunction in aged skin

( Beom Jun Kim ),( Noo Ri Lee ),( Chung Hyeok Lee ),( Young Bin Lee ),( Solam Lee ),( Hyun Jee Hwang ),( Eunjung Kim ),( Eung Ho Choi ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.2

Background: 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts inactive cortisone into cortisol, an active form, and is expressed by several tissues including the skin. Excessive active glucocorticoid (GC) deteriorates skin barrier function. Objectives: To find out if 11β-HSD1 affects on the barrier function in aged skin. Methods: We have performed human and in vivo studies. We measured cortisol in stratum corneum (SC) and oral epithelium of the elderly and young. Hairless mice were used for 11β-HSD1 immunohistochemistry staining of skin and measuring skin barrier function and serum cytokines. 11β-HSD1 knock-out (KO) mice and its wild-type were used for measuring lipid synthesis related enzyme. Results: Cortisol levels were elevated in SC and oral epithelium of the elderly rather than young. The 11β -HSD1 expression was increased in immunohistochemistry stain of aged mice skin. Aged mice showed decreased transepidermal water loss (TEWL) and SC hydration, and increased SC integrity than young. Serum inflammatory cytokines including interleukin-1α, -4, -10, -31 and tumor necrosis factor-α were increased in aged mice than young. The expressions of lipid synthesis related enzymes in epidermis were elevated in KO mice and topical 11β -HSD1 inhibitor applied mice. Conclusion: 11β-HSD1 expression is elevated in aged skin. It increases active GC and then deteriorates skin barrier function.

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

노화가 인체 중간엽 줄기세포로부터 조골세포로의 증식 및 분화에 미치는 영향

백기현,태현정,오기원,이원영,조정기,권순용,강무일,차봉연,이광우,손호영,강성구,김춘추 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.3

연구배경: 일반적으로 골다공증과 연관된 위험인자로는 연령, 폐경, 약물, 불충분한 칼슘섭취, 만성질환 및 운동부족 등이 있는데, 특히 노화가 진행할수록 골밀도가 감소하는 것은 잘 알려져 있다. 노화와 관련하여 진행되는 골소실은 조골세포 및 전구조골세포의 기능적 결핍에 의한 골형성의 감소가 주요한 요인으로 여겨지고 있다. 그 동안 연령이 조골모 세포의 양과 조골모 세포로부터 성숙조골세포로의 분화 및 증식에 미치는 영향에 대한 일부 보고들이 있었으나 아직 일치된 견해는 없는 형편이다. 방법: 다양한 연령의 사람으로부터 골수를 채취, 중간엽 줄기세포가 포함된 단핵세포를 분리한 후 조골세포로 분화하기 좋은 조건하에서 배양하였다. 대상군은다시 젊은군과 노령군으로 구분하여 다양한 변수를 비교 분석하였다. 일차배양에서는 CFU-F를 계수하여 골수내 중간엽 줄기세포의 수를 추산하였고, 칼슘측정을 통하여 기질의 무기화 정도를 비교하였다. 계대배양후 이차배양에서는 시기별로 알카리성 포스파타제 활성도를 측정하고 오스테오칼신 mRNA의 발현을 관찰하여 젊은군과 노령군 사이의 증식능 차이를 비교하였다. 또한 이차배양 시기별로 MTT 측정을 하여 양군간에 증식능 차이가 있는지 알아보았다. 결과: 1. 일차배양 15일째에 평균 CFU-F의 수는 젊은군에서 유의하게 많았다(젊은군 148.3±28.9, 노령군 54.3±9.1, p=0.02). CFU-F의 평균면적은 젊은군에서 넓은 경향을 보였으나 통계적으로 유의하지는 않았다. 2. 일차배양 17일 경과 후 양군간에 기질 칼슘 침착정도는 유의한 차이를 보이지 않았다(젊은군 103.6±50.6, 노령군: 114.0±56.5, p=NS). 3. 이차배양 10일째에 젊은군에서 알카리성 포스파타제 활성도가 고령군에 비해 유의하게 높았다(젊은군: 935.5±115.0 U/mg, 노령군: 578.4±115.7U/mg,p.0.05). 고령군에서는 시간 경과에 따른 변화가 미약했으며 전반적으로 알카리성 포스파타제의 활성도가 젊은군에 비해 낮았다. 4. 이차배양도중 오스테오칼신 mRNA의 발현은 배양시기별로 젊은군에 비해 고령군에서 더 낮은 경향을 관찰할 수 있었다. 5. 이차배양 10일과 15일에 젊은군에서 노령군보다세포증식이 유의하게 증가된 양상을 보였다(10앓 젊은군 0.73±0.05, 노령군 0.58±0.04, p=0.05, 15일; 젊은군 0.80±0.05, 노령군 0.70±0.03, p=0.05).결론: 이상의 연구에서 저자들은 노령군에서 젊은군보다 골수 내 중간엽줄기세포의 수가 적고, 노령군에서 유래한 전구조골세포의 성숙조골세포로의 증식 및 분화가 젊은군 보다 감소해 있는 것을 관찰할 수 있었다. Background: Osteoblasts originate from osteoprogenitor cells in bone marrow stroma, termed mesenchymal stem cells (MSCs) or bone marrow stromal cells. Each MSC forms colonies (colony forming units-fibroblasts [CFL-Fs]) when cultured ex vivo. There are some reports about the age-related changes of the number and osteogenic potential of osteoprogenitor cells, but any relationship has not been clearly established in humans. In this study, we counted MSCs using CFU-Fs count and examined the proliferative capacity and differentiation potential of osteoprogenitor cells. Finally, we analyzed how these parameters varied with donor age. Methods: Bone marrow was obtained from the iliac crest of young (n=6, 27.2±8.6 years old) and old (n= 10, 57.4k6.7 years old) healthy donors. Mononuclear cells, including MSCs, were isolated and cultured in osteogenic medium. In primary culture, we compared the colony-forming efficiency of MSCs between the two groups and determined the matrix calcification. When primary culture showed near confluence, the cells were subcultured. Alkaline phosphatase activity, osteocalcin expression by RT-PCR and proliferative potential by MTT assay were examined by the time course of secondary culture. Results: At the 15th day of primary culture, the mean number of CFU-Fs was significantly higher in the younger donors (young: 148.3±28.9, old: 54.3±9.1, p=0.02) and the mean size of CFL-Fs was also larger in the younger donors than the older donors. However, matrix calcification was not different between the two groups (young: 103.6±50.6, old: 114.0±56.5, p=NS). In secondary culture, alkaline phosphatase activities were significantly lower in the older donors. The younger donors showed peak alkaline phosphatase activity at day 10, while the older donors didn't showed a remarkable peak (young: 935.5±115.OU/mg, old: 578.4±115.7U/mg, p<0.05). Total cell number as a proliferative index increased progressively during the secondary culture and a significantly greater cell number was noted in the younger donors. Osteocalcin expression was generally upregulated in the younger donors, but this was not statistically significant. Conclusion: Our study shows that the number of osteoprogenitor cells is decreased during aging and that the proliferative capacity and differentiation potential of osteoprogenitor cells seem to be reduced during aging (J Kor SOC Endocrinol 18:296-305, 2003).

고령자 급성 췌장염의 임상적 고찰

백용한,서정훈,송건훈,이진헌,송시영,정재복,강진경,박인서,이수진 大韓消化器病學會 1998 大韓消化器病學會誌 Vol.32 No.3

감마선(^60Co) 조사에 의한 항진균 세균의 돌연변이체 유도

정혜영,이영근,김재성,조규성,이영복 한국환경농학회 2002 한국환경농학회지 Vol.21 No.3

항진균 세균의 특성 및 기능변화 가능성을 조사하기 위하여 버섯폐배지, 온천수, 해조류 및 삼림토양으로부터 식물병원성 진균에 대한 8 종의 항진균 활성 균주를 분리하였고 감마선(^60Co)을 이용하여 LD_95 에 돌연변이체를 유도하였다. Bactllus circulans K1, Burkholderia gladioli K4와 Bacillussubtilis YSl은 12 종의 식물병원성 진균에 대go 항진균 활성을 보였다. 이들 균주의 방사선감수성 조사결과 B. gladioliK4는 감마선에 대한 높은 감수성을 보였으며, D_10 값은 0.11kGy 였다. 감마선에 의해 유도된 Kl-1004와 YSl-1009는Botryosphaeria dothidea에 대해 항진균 활성이 증가되었다. B.subtilis YS1의 돌연변이체인 YSl-1006과 YS1-1009는 tebuconazol과 copper hydroxide에 대해 농약 저항성을 나타냈다. SAR535, SAR5108 과 SAR5l18 돌연변이체는 야생형 균주인 Streptomyces sp. SAR01에 비해 5 종의 식물병원성 진균에 대해 항진균 활성이 없었다. 연구결과, 방사선을 이용하여 다양한 기능의 돌연변이체 유도가 가능하였다. 이를 이용하여 항진균 활성 관련 유전자 연구 및 균주개량이 가능할 것으로 사료된다. In order to evaluate the antifungal activity of bacteria against plant pathogenic fungi, 8 bacteria were isolated from mushroom compost, hot spring, seaweed, and forest soil and mutants from them were induced by LD_(95) gamma radiadon(^(60)Co). Bacillus circuluns K1, Burkholderia gladioli K4 and Bacillus subtilis YS1 showed wide antifungal spectrum against 12 kinds of plant pathogenic fungi. From the radiation sensitivity test, R gladioli K4 was very sensitive to gamma radiation and its D_(10) value was 0.11 kGy. Antifungal activities of B. circulans K1-1004 and B. subtilis YS1-1009, which were induced by the radiation of ^(60)Co increased against Botryosphaeria dothidea. The mutant strains, B. subtilis YS1-1006 and B. subtilis YS1-1009 were resistant to tebuconazole and copper hydroxide. SAR535, SAR5108, and SAR5118 mutated from Streptomyces sp. SAR01 were antifungal activity deficient mutants against 5 kinds of plant pathogenic fungi compared to wild strain, so that they could be supposed to be model strains for studying antifungal mechanism. It is suggested that various functional types of mutants could be induced by gamma radiation and applied usefully.

Superconducting MgB2 Wire Drawing Considering Anisotropic Hardening Behavior and Hydrostatic Effect

Young‑Seok Oh,Ho Won Lee,Kook‑Chae Chung,Duck‑Young Hwang,Seong‑Hoon Kang,Jeong Whan Yoon 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

Numerical modeling was conducted to investigate the deformation behavior of powder mixture during multi-pass drawingprocesses for multi-filamentary MgB2wire. A modified Drucker-Prager Cap (DPC) model with an elliptical cap surface usingthe new material characterization method was developed to capture the anisotropic hardening behavior and hydrostatic effectof the powder mixture. A number of uniaxial die compaction, cold isostatic pressing, diametrical compression, and uniaxialcompression tests were conducted using different powder densities to characterize the modified DPC model. A commercialfinite element software ABAQUS with a user subroutine was used to simulate the drawing of the MgB2wire. The densityand area fraction of the powder mixture during the wire-drawing process were verified with experimental results. The differencein packing density at the inner and outer filaments of the MgB2wire was successfully captured by simulation. Inaddition, the effect of the initial packing density on the superconducting properties of MgB2wire was numerically studied. It is shown that the increase in the superconducting area, which results from a high initial packing density, should be moreeffective compared to the increase in the grain connectivity in enhancing the critical current properties for the MgB2wirewhen the final packing density is saturated after a number of drawing processes.