Role of the Oxidizing Agent in the Etching of 4H-SiC Substrates with Molten KOH

Moonkyong Na,In-Ho Kang,Jeong Hyun Moon,Wook Bahng 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.11

A novel etching solution using molten potassium hydroxide (KOH) for the identification of dislocation types in a silicon-carbide (SiC) epilayer is identified. Threading screw dislocations (TSDs) and threading edge dislocations (TEDs) are rarely useful for size-based differentiation of etch pits in highly nitrogen (N)-doped SiC through conventional KOH etching. In this study, we report the role of sodium peroxide (Na2O2) and potassium dioxide (KO2) as oxidizing agent additives to the etchant for identifying the dislocation types in highly N-doped 4H-SiC. A Na2O2-KOH phase diagram was calculated to predict the chemical composition of the etchant. Solid-phase Na2O2 remained in the system when added to the etchant at concentrations greater than 13-wt% Na2O2, and it provided excess oxygen to the etchant. We experimentally confirmed that etch pit shapes became more hexagonal and that the etch pit sizes of TSDs and TEDs differed more greatly when more than 20-wt% Na2O2 was added to the etchant. We also found that the size distribution of TEDs was much smaller than that of TSDs after etching using Na2O2-KOH. Dissolved oxygen played an essential role in enhancing the anisotropic etching of highly N-doped SiC and allowed the dislocation types to be identified.

Acute inflammation reveals GABAA receptor‐mediated nociception in mouse dorsal root ganglion neurons via PGE ₂ receptor 4 signaling

Jang, In Jeong,Davies, Alexander J.,Akimoto, Nozomi,Back, Seung Keun,Lee, Pa Reum,Na, Heung Sik,Furue, Hidemasa,Jung, Sung Jun,Kim, Yong Ho,Oh, Seog Bae John Wiley and Sons Inc. 2017 Physiological reports Vol.5 No.8

<P><B>Abstract</B></P><P>Gamma‐aminobutyric acid (GABA) depolarizes dorsal root ganglia (DRG) primary afferent neurons through activation of Cl<SUP>−</SUP> permeable GABAA receptors but the physiologic role of GABAA receptors in the peripheral terminals of DRG neurons remains unclear. In this study, we investigated the role of peripheral GABAA receptors in nociception using a mouse model of acute inflammation. In vivo, peripheral administration of the selective GABAA receptor agonist muscimol evoked spontaneous licking behavior, as well as spinal wide dynamic range (WDR) neuron firing, after pre‐conditioning with formalin but had no effect in saline‐treated mice. GABAA receptor‐mediated pain behavior after acute formalin treatment was abolished by the GABAA receptor blocker picrotoxin and cyclooxygenase inhibitor indomethacin. In addition, treatment with prostaglandin E2 (PGE<SUB>2</SUB>) was sufficient to reveal muscimol‐induced licking behavior. In vitro, GABA induced sub‐threshold depolarization in DRG neurons through GABAA receptor activation. Both formalin and PGE<SUB>2</SUB> potentiated GABA‐induced Ca<SUP>2+</SUP> transients and membrane depolarization in capsaicin‐sensitive nociceptive DRG neurons; these effects were blocked by the prostaglandin E2 receptor 4 (EP4) antagonist AH23848 (10 <I>μ</I>mol/L). Furthermore, potentiation of GABA responses by PGE<SUB>2</SUB> was prevented by the selective Na<SUB>v</SUB>1.8 antagonist A887826 (100 nmol/L). Although the function of the Na<SUP>+</SUP>‐K<SUP>+</SUP>‐2Cl<SUP>‐</SUP> co‐transporter NKCC1 was required to maintain the Cl<SUP>‐</SUP> ion gradient in isolated DRG neurons, NKCC1 was not required for GABAA receptor‐mediated nociceptive behavior after acute inflammation. Taken together, these results demonstrate that GABAA receptors may contribute to the excitation of peripheral sensory neurons in inflammation through a combined effect involving PGE<SUB>2</SUB>‐EP4 signaling and Na<SUP>+</SUP> channel sensitization.</P>

Up-regulation of Heme Oxygenase-1 by Korean Red Ginseng Water Extract as a Cytoprotective Effect in Human Endothelial Cells

Yang, Ha-Na,Lee, Seung-Eun,Jeong, Seong-Il,Park, Cheung-Seog,Jin, Young-Ho,Park, Yong-Seek The Korean Society of Ginseng 2011 Journal of Ginseng Research Vol.35 No.3

Korean red ginseng (KRG) is used worldwide as a popular traditional herbal medicine. KRG has shown beneficial effects on cardiovascular diseases, such as atherosclerosis, diabetes, and hypertension. Up-regulation of a cytoprotective protein, heme oxygenase (HO)-1, is considered to augment the cellular defense against various agents that may induce cytotoxic injury. In the present study, we demonstrate that KRG water extract induces HO-1 expression in human umbilical vein endothelial cells (HUVECs) and possible involvement of the anti-oxidant transcription factor nuclear factor-eythroid 2-related factor 2 (Nrf2). KRG-induced HO-1 expression was examined by western blots, reverse transcriptase polymerase chain reaction and immunofluorescence staining. Specific silencing of Nrf2 genes with Nrf2-siRNA in HUVECs abolished HO-1 expression. In addition, the HO inhibitor zinc protoporphyrin blunted the preventive effect of KRG on $H_2O_2$-induced cell death, as demonstrated by terminal transferase dUTP nick end labeling assay. Taken together, these results suggest that KRG may exert a vasculoprotective effect through Nrf2-mediated HO-1 induction in human endothelial cell by inhibition of cell death.

한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

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.

본태성 고혈압쥐에서 Myogenic Tone의 변화:RhoA 단백질 및 Protein Kinase C의 역할

서정필,류성경,강나영,안덕선,이영호 대한순환기학회 2002 Korean Circulation Journal Vol.32 No.3

개에서 발생한 동맥관개존증 치료 증례

조나영,박성준,최호정,정성목,송근호 忠南大學校 獸醫科大學 附設 動物醫科學硏究所 2012 動物醫科學硏究誌 Vol.19 No.1

A Bicon Frise (7-month-old, intact female, B.W.: 3.5kg) was referred to the Veterinary Medical Teaching Hospital of Chungnam National University with the history of the murmur which was picked up during routine vaccination. The grade 3 of continuous murmur was identified on the auscultation. In the thoracic radiography, descending aorta and main pulmonary artery were enlarged and vertebral cardiac scale (VHS) was 10. In the echocardiography, turbulent and continuous positive flow was identified in the pulmonary artery at the right parasternal short axis view. We found the patent ductus arteriosus (PDA) connected the main pulmonary artery with the aorta by CT image. So, the diagnosis of PDA was made. The continuous murmur was not identified on the auscultation after surgical correction was achieved by ligation of PDA.

혈액암환자에서 조혈모세포 이식 후 따르는 헤르페스 바이러스 감영 양상

이호섭,탁희상,신성훈,김양수,남성진,김혜수,박진희,정수현,김성빈,김예나 고신대학교 의과대학 2010 고신대학교 의과대학 학술지 Vol.25 No.1

배경 : 헤르페스바이러스과에는 단순포진 바이러스(HERPES SIMPLEX VIRUS, HSV), 수두대상포진 바이러스 (VARICELLA-ZOSTER VIRUS, VZV), 엡스타인-바 바이러스 (EPSTEIN-BARR VIRUS, EBV), 그리고 거대세포 바이러스 (CYTOMEGALOVIRUS, CMV) 등이 있다. 헤르페스바이러스 감염은 혈액암환자에서 조혈모세포 이식 환자에서 전파 (dissemination), 이차감염, 세균 중복 감염의 심각한 합병증을 일으킬 수 있다. 하지만 항암약물치료를 받는 림파종 환자에서 항 바이러스 약제의 사용 용량과 기간에 대한 concensus는 없다. 헤르페스바이러스 감염에 대한 발생율과 위험인자를 후향성으로 분석하였다. 방법 : 고신대학교 복음 병원에서 1995년 6월부터 2009 년 2월 사이에 새롭게 진단되어 조혈모세포 이식을 받은 전체 58명의 환자들이 후향적으로 현 연구에 등록했다. 헤르페스 바이러스 감염은 임상적 진단, 혈청학적 검사 또는 병리학적 진단에 기초하여 확진한다. 환자들의 특성은 다음과 같다: 평균 연령은 44세 (범위 19-62세)였고 남녀비는 30:28이었다. 등록된 질환은 백혈병 (n=9, 15.5%), 림프종 (n=30, 51.7%), 다발성 골수종 (n=12, 20.7%), 재생불량성 빈혈 (n=6, 10.3%) 그리고 골수이형성증후군 (n=1, 1.7%)이 포함되었다. 결과는 chi-squre test나 independent samples T test를 사용하여 분석되었다. Multivariate analysises에 대해 logistic regression test를 사용하였다. 결과 : 15명의 환자들 (25.9%)에서 조혈모세포 이식후 헤르페스 바이러스 감염이 발생하였다. 조혈모세포 이식 5년간 누적 발생율은 53.9%였다. Univariate analyses에서 헤르페스 바이러스 감염에 대한 유의한 위험 인자는 없었다. 하지만 조혈모세포 이식후 생존 기간(40.18 ± 30.14 months vs 20.06 ± 26.67 months, p=0.018)은 헤르페스 바이러스 감염의 낮은 발병율과 유의한 관련성이 있었다. 이식 편대 숙주질환 (GVHD)의 존재 (37.5% in developed GVHD vs 0% in no GVHD, p=0.200), 동종조혈 모세포 이식에서 면역억제요법의 기간 (15.98 ± 14.02 months vs 6.78 ± 3.67 months, p = 0.374)은 헤르페스 바이러스 감염에 대한 위험인자가 아니었다. 결론 : 조혈모세포 이식 후 생존 기간은 어사이클로비어 예방을 받은 혈액암 환자에서 헤르페스 바이러스 감염의 낮은 발병율과 연관성이 있는 것으로 보인다. 저용량의 어사이클로비어 예방은 헤르페스 바이러스 감염의 고위험군인 조혈모세포 이식을 받은 혈액암 환자에 필요하리라 생각된다. Background : Herpesviridae family includes herpes simplex virus, varicella zoster virus, Epstein-Barr virus, and cytomegalovirus, etc. Herpesviridae viral infection (HVI) can lead to serious complications including dissemination, secondary infection, bacterial superinfection in patients with hematologic malignancy following hematopoietic stem cell transplantation (HSCT). But there was no consensus on the dose and duration of antiviral agents prophylaxis in patients undergoing chemotherapy. We retrospectively analyzed the incidence and the risk factors for HVI. Method : A total of 58 patients who newly diagnosed and received HSCT with prophylaxis of acyclovir at the Kosin University Gospel Hospital, Busan, Korea between June 1995 and February 2009 were enrolled retrospectively in the current study. HVI was confirmed based on clinical diagnosis, serologic test or pathologic diagnosis. The characteristics of the patients were as follows: the median age was 44 years (range 19-62 years) with a female-to-male ratio of 30:28. The enrolled diseases included leukemia (n=9, 15.5%), lymphoma (n=30, 51.7%), multiple myeloma (n=12, 20.7%), aplastic anemia (n=6, 10.3%) and myelodysplastic syndrome (n=1, 1.7%). The results were analyzed using a chi-square test and independent samples T test. For the multivariate analysis, we used logistic regression test. Results : Fifteen patients (25.9%) developed HVI after HSCT. The cumulative incidence of HVI was 53.8% at 5 years after HSCT. In univariate analysis, there was no significant risk factor for HVI. The presence of graft-versus-host disease (GVHD) (37.5% in developed GVHD vs. 0% in no GVHD, p=0.200), duration of immunosuppressive therapy (IST) in allo-SCT (15.98 ± 14.02 months vs. 6.78 ± 3.67 months, p = 0.374) were not risk factors for HVI. Conclusion : The incidence of HVI was similar to that in historical other studies. There was no risk factor associated with development of HVI. Most of the HVI occurred within the first 24 months after transplantation. So long term use of antiviral prophylaxis may be needed to prevention of HVI after HSCT.

분쇄육에서 산, 염, 열처리 및 천연항균물질 처리가 도체표면으로부터 분리한 병원성미생물의 생존에 미치는 효과

이신호,정영숙,박나영 한국식품저장유통학회 ( 구 한국농산물저장유통학회 ) 2003 한국식품저장유통학회지 Vol.10 No.3

도체표면에서 분리한 E. coli O157:H7 CDF1, A. sobria CDF3, S. aureus CDF2의 성장을 억제하기 위한 방안을 검토하였다. E. coli O157:H7 CDF1, A. sobria CDF3는 NaC1 4%이상 농도에서 성장이 억제된 반면 lactic acid 0.1%는 성장에 영향을 미치지 않았다. S. aureus CDF2은 NaCl 농도 4%에 의해 성장이 뚜렷하게 억제되지 않았으나 lactic acid 0.1% 첨가에 의해 뚜렷히 억제되었다. E. coli O157:H7 CDF1은 분쇄육에서 4℃와 10℃에서 저장하는 동안 저장온도별 약 1log 차이를 나타내었고, A. sobria CDF3의 성장은 저장온도에 따른 차이는 나타나지 않았다. 60℃에서 10분 열처리 후 E. coli O157:H7 CDF1, A. sobria CDF3가 거의 사멸하였으나 S. aureus CDF2는 대조구에 비해 1log cycle 이하의 감소현상을 나타내었다. 감잎, 뽕잎, 녹차, 우롱차의 추출물중 E. coli O157:H7 CDF1, A. sobria CDF3, S. aureus CDF2에 대한 항균활성을 나타낸 우롱차 추출물 0.1%와 0.3% 첨가에 의해 E. coli O157:H7 CDF1는 성장 억제되지 않았으나 0.5%첨가구의 경우 약 2 log 감소하였다. A. sobria CDF3와 S. aureus CDF2는 추출물 0.1%와 0.3%첨가에 의해 성장이 억제되었으며 0.5%첨가에 의해 배양 12시간이후 생균수는 검출되지 않았다. 우롱차 추출물을 분쇄육에 0.3%와 0.5%를 첨가하여 20℃에서 24시간 저장한 결과는 E. coli O157:H7 CDF1, A. sobria CDF3, S. aureus CDF2은 우롱차 추출물을 0.5첨가한 경우 성장이 억제되는 경향을 나타내었다. Effects of acid, salt, heat treatment and natural antimicrobials on survival of E. coil O157:H7 CDF1, A. sobria CDF3 and S.aureus CDF2 isolated from surface of carecass in minced meat was investigated. The growth of E. coli O157:H7 CDF1 and A. sobria CDF3 inhibited in minced meat congtaining above 4% NaCL but not in 1% lactic acid. The growth of S. aureus CDF2 yas not inhibited significantly by addition of 4% NaCl but inhibited completely in minced meat containing 1% lactic acid. Survial of A. sorbia CDF3 did not show any differences during storage at 4 and 10℃. E. coli O157:H7 CDF1 and A.sobria CDF3 did not detect after heat treatment at 60℃ for 10 min but S. aureus CDF2 decreased only 1 log after the same treatment. Viable cell of E. coli O157:H7 CDF1 decreased 2 log in TSB containing 0.5% Oolong tea extract after incubation for 12 hr compared with control but A. sobria CDF3 and S.aureus CDF2 did not detect at the same condition. The growth of E. coli O157:H7 CDF1, A. sobria CDF3 and S.aureus CDF2 was not inhibited by addition of 0.3% Oolong tea extract but inhibited by addition of 0.5% Oolong tea extract in minced meat at 20℃ for 24hr.

Cloning, Purification, and Characterization of a New DNA Polymerase from a Hyperthermophilic Archaeon, Thermococcus sp. NA1

( Yun Jae Kim ),( Hyun Sook Lee ),( Seung Seob Bae ),( Jeong Ho Jeon ),( Jae Kyu Lim ),( Yo Na Cho ),( Ki Hoon Nam ),( Sung Gyun Kang ),( Sang Jin Kim ),( Suk Take Kwon ),( Jung Hyun Lee ) 한국미생물생명공학회 2007 Journal of microbiology and biotechnology Vol.17 No.7