Conceptual Study for Tissue-Regenerative Biodegradable Magnesium Implant Integrated with Nitric Oxide-Releasing Nanofi bers

Jin‑Kyung Jeon,Hyunseon Seo,Jimin Park,Soo Ji Son,Yeong Rim Kim,Eun Shil Kim,Jong Woong Park,Woong‑Gyo Jung,Hojeong Jeon,Yu‑Chan Kim,Hyun‑Kwang Seok,Jae Ho Shin,Myoung‑Ryul Ok 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.4

The excessive initial corrosion rate of Mg is a critical limitation in the clinical application of biodegradable Mg implantsbecause the device loses its fi xation strength before the fractured bone heals. This study suggests a new approach to overcomethis hurdle by accelerating tissue regeneration instead of delaying the implant biodegradation. As angiogenesis is anessential process in early bone regeneration, a Mg implant coated with electrospun nanofi bers containing nitric oxide (NO),which physiologically promotes angiogenesis, is designed. The integrated device enables adjustable amounts of NO to bestored on the NO donor-conjugated nanofi ber coating, stably delivered, and released to the fractured bone tissue near theimplanted sites. An in vitro corrosion test reveals no adverse eff ect of the released NO on the corrosion behavior of the Mgimplant. Simultaneously, the optimal concentration level of NO released from the implant signifi cantly enhances tube networkformation of human umbilical vein endothelial cells without any cytotoxicity problem. This indicates that angiogenesis canbe accelerated by combining NO-releasing nanofi bers with a Mg implant. With its proven feasibility, the proposed approachcould be a novel solution for the initial stability problem of biodegradable Mg implants, leading to successful bone fi xation.

다제내성 그람양성균에 대한 Linezolid(Zyvox^(�))의 시험관내 항균력 비교

박대원,정희진,엄중식,황병연,김성범,이재갑,이연주,정혜원,정성주,박재형,이진수,손장욱,김우주,김민자,박승철 대한감염학회 2003 감염과 화학요법 Vol.35 No.5

배경 : MRSA, VRE, VRSA같은 다제 내성 그람 양성균의 등장에 따라 glycopeptide를 대체할 새로운 항생제의 개발이 필요하게 되었고 결과적으로 새로운 항생제인 linezolid라는 항생제가 개발되었다. Linezolid는 이전의 항생제와는 다른 새로운 계열의 oxazolidinone으로 경구 이용률이 우수하다. 원내 및 원외감염의 중요한 원인균이 되고 있는 MRSA, VRE에 대한 적절한 경구용 항균제가 없는 국내에서 폐렴 및 피부 연조직 감염에서 경구용으로 사용해 볼 수 있는 약제이다. 본 연구에서는 고대 구로 병원에서 분리된 MRSA, VRE 등을 대상으로 다른 여러 항균제와 비교한 linezolid의 시험관내 항균력을 조사하고자 하였다. 재료 및 방법 : 연구대상은 1998년 1월부터 2000년 12월까지 본원에서 입원 및 외래를 통하여 피부 연조직 감염증 및 호흡기 감염증, 요로감염증으로 진단된 환자들의 가검물로부터 분리된 MRSA 60균주, VRE 43균주, PRSP 25균주를 액체배지 또는 한천배지 희석법을 통하여 linezolid 및 기타 항균제에 대한 최소발육억제농도를 구하였다. 결과 : 실험에 사용한 S. aureus는 모두 MRSA였고 이들은 linezolid에 대해 MIC_(90) 2㎍/㎖(MIC 범위 1-2㎍/㎖), Enterococcus spp는 모두 VRE로 linezolid의 MIC_(90)은 2㎍/㎖로 MIC 범위는 1-4㎍/㎖였다. 한 개의 균주에서 MIC 4㎍/㎖로 중등도 감수성을 보였으나 MIC breakpoint가 (8㎍/㎖인 내성균주는 없고 모두 감수성을 보였다. S. pneumoniae의 경우 penicillin 내성이었고, linezolid MIC_(90) 1㎍/㎖ (MIC 범위 0.5-1㎍/㎖)로 전부 감수성을 보였다. 결론 : Linezolid는 MRSA를 위시한 VRE, PRSP 등의 다제 내성 그람 양성균에 대하여 우수한 시험관내 항균력을 보임을 알 수 있었다. Background : The emergence of multi-drug resistant Gram-positive cocci, such as MRSA, VRE, and VRSA, necessitated to develop new antibiotics, which could replace the glycopeptide. As a result, a new antibiotics named linezolid was developed. Linezolid is different line of oxazolidinones with a good oral bioavailability, compared to other antibiotics. Since appropriate oral antibiotics are not presently available for MRSA, which is a major cause of nosocomial and community acquired infections, the introduction of linezolid will have favorable effect on treatment of infections such as pneumonia or skin infections. In this study, we investigated the antibiotic effect of linezolid on MRSA and VRE isolated from patients who were treated in Korea University Guro Hospital. Material and Methods : By using broth microdilution and agar dilution method we measured minimum inhibitory concentration (MIC) with sixty S. aureus, forty three Enterococcus spp., and twenty five S. pneumoniae isolates from patients who were diagnosed as skin, soft tissue, respiratory, and urinary infections in Korea University Guro Hospital from January, 1998 to December, 2002. Results : All of S. aureus used in this study were MRSA, and MIG_(90) of linezolid was below 2 ㎍/㎖ (MIC ranged between 1-2 ㎍/㎖). All of Enterococcus spp. were VRE, and had MIG_(90) of 2 ㎍/㎖ (MIC ranged between 1 to 4 ㎍/㎖). One of the VRE showed intermediate susceptibility with MIC of 4 ㎍/㎖. However, none was resistant with MIC breakpoint above 8 ㎍/㎖. All of S. pneumoniae were resistant to penicillin, but they were susceptible to linezolid with MICao of 1 ㎍/㎖(MIC range 0.5-1㎍/㎖). Conclusion : In conclusions, linezolid has an excellent in vitro antibiotic effect on multi-drug resistant Gram-positive cocci, such as MRSA, PRSP, and VRE.

동일한 국제예후지표(International Prognostic Index)를 나타내는 미만성 대형 B-세포 림프종에서 Bcl-2와 p16의 임상적 중요성

박상은,박수진,곽승근,박남숙,천재민,윤환중,조덕연,김삼용,김진만 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

In Korea, malignant lymphoma is a common cancer, comprising about 2.7% of all malignant neoplasm. Diffuse large B cell lymphoma is the most common lymphoma, representing about 50% of all Non-Hodgkin's lymphoma. Diffuse large B-cell lymphoma is usually considered as heterogeneous group of neoplasms rather than a single clinicopathological entity. Clinical prognostic systems, including the International Prognostic Index (IPI), although useful to assess overall prognosis, embrace patients with heterogeneous prognoses. But International Prognostic Index scoring system is not sufficiently predict the prognosis. It is likely that the prognostic assessment of patients with diffuse large B-cell lymphomamight be improved by using biological features. Bcl-2 protein and p16 protein expression is recognized as useful biologic markers predicting the prognosis of patients with diffuse large B-cell lymphoma. To determine the clinical significance and prognostic value of bcl-2 and p16 proteins expression patterns, we studied 18 patients with de novo DLBL, whose archival pathology specimen were available for immunohistochemistry studies, atChungnam National University Hospital from September 1992 to December 2000. Archival specimens from each patient were immunostained with respective antibodies for bcl-2, p16. The results are as follows; 1) The median age was 54(rage : 37-69). There were 12 male patients(66.7%) and 6 female patients(33.3%) The 'B' symptom was abscentin all patients. The stages were as follows : Ⅰ, 2 patient(11.1%), Ⅱ, 10 patient(55.6%), Ⅲ, 4patient(22.2%) and Ⅳ, 2patient(11.1%). 3 patients(16.8%) had the elevated LDH level, 14 patients(77.8%) had the normal LDH level and 1 patients(5.6%) was not identified the LDH level. 2 patients(11.1%) had the bulky disease and 16 patients(88.7%) had no bulky diease. The distribution of ECOG status were O, 2 patients(11.1%c), 1, 14patients(77.8%) and 2, 2patients(11.1%). 2) Theimmunohistochemistry results are as follows bcl-2:+,10 patients(55.6%), bcl-2:-, 8patinets(44.4%), p16:+,3 patients(16.7%), p16:-, 15patients(83.3%) 3) After a median follow UP durations of 67 months, the median survival time was 57 months with a rage of 7-100+ months. 5-years overall survival rates was 44% by Kaplan-Meier method. 4) Reduced overall survival was demonstrated in the patients who expressed bcl-2 protein(P=0.0174). 5-year overall survivial rate was 12%(bcl-2 expression) versus 88%(no bcl-2 expression) 5) Among diffuse large B-cell lymphoma patients with IPI score 0-1, reduced overall survival was demonstrated with bcl-2 expression(P=0.023). 5-year overall survival rate was 18%(bcl-2 expression group) versus 100%(no bcl-2 expressiongroup) 6) Median survival durtation of diffuse large B-cell lymphoma patients negative for p16 expression was 57 months whereas p16 postive patients' median survival duration was not reached(P=0.4478). In diffuse large B-cell lymphoma patients with identical IPI scores, bcl-2 expression had additional prognostic value.

PLT 절연층을 이용한 ZnS:Mn TFEL소자의 제조 및 특성

박욱동,박경빈,박재현,김영진,최병진,김기완 경북대학교 센서기술연구소 1995 센서技術學術大會論文集 Vol.6 No.1

Thin film electroluminescent(TFEL) device has been fabricated using ZnS:Mn phosphor and PLT insulator. The ZnS:Mn and PLT thin film for TFEL device was deposited by vacuum evaporation method and RF magnetron sputtering method, respectively. The TFEL device using ZnS:Mn(6000 Å) and PLT(1000 Å) thin films showed the threshold voltage of 50 Vrms at the driving frequency of 3 kHz. The brightness of TFEL device was 250 μW/cm^(2) at the applied voltage of 74 Vrms. Also the output current of TFEL device was linearly increased with applied voltage.

Consideration of Diluents Selection and Input Amounts of the Hunter Process for Tantalum Production

Jae‑Jin Sim,Sang‑Hoon Choi,Yong‑Kwan Lee,Sung Gue Heo,Taek‑Soo Kim,Seok‑Jun Seo,Kyoung‑Tae Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.7

Tantalum (Ta) is a heavy refractory metal with an atomic weight of 180.95 g/mol, a density of 16.6 g/cm3, and a high meltingpoint of 3017 °C. With its refractory characteristics, it shows excellent chemical and physical stability as well as corrosionand heat resistance at elevated temperatures. The demand for Ta metal and related compounds is increasing with the expansionof the electronics and chemical industries. The Hunter process was proven to be effective in producing Ta powder in1953. Hunter proposed a method in which potassium heptafluorotantalate (K2TaF7) was reduced by sodium (Na). Thus far,this process has been the primary commercial method to produce Ta powder. In this study, quantitative differences wereanalyzed for diluent selection. Additionally, consideration was given to changes in the caloric value depending on the inputamount of diluents. Finally, the optimum material input and the properties of the prepared Ta were analyzed. Stoichiometricratios of K2TaF7(1 mol), NaCl (6.2–6.7 mol), Na (5–7 mol) were weighed, to perform a metallothermic reduction reaction. After the reaction, the tantalum powder was recovered and the flush process was carried out. After that, it was dried in avacuum atmosphere. Physical properties such as oxygen concentration, PSA, ICP-OES, and XRD of powder were conductedto evaluate the characteristics of Ta powder that was finally manufactured.

조기 대장암

이재범,박영진,박군주,김선회,박재갑,이건욱,박용현,최국진,김진복 대한대장항문학회 1998 Annals of Coloproctolgy Vol.14 No.3

연령증가에 따른 혈압요소들의 좌심실비대 및 관동맥질환과의 관련성

박재석,박창규,박미영,박재형,김용현,나진오,신성희,서순용,홍순준,박성미,임홍의,김응주,서홍석,오동주,노영무 대한순환기학회 2004 Korean Circulation Journal Vol.34 No.2

곰쓸개 복용 후 발생한 육안적 혈뇨와 신유두부 괴사증 1예

김우진,한민석,김수항,박인형,박진석,선제형,홍세인,박옥영,신정현,이숭,신병철 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.3

Renal papillary necrosis occurs most commonly in association with urinary tract infection, diabetes mellitus, sickle cell disease, vascular disease, and analgesic nephropathy. Clinical presentation may be related to symptoms of pyelonephritis such as flank pain, renal colic, hematuria, Proteinuria, recurrent fever. The necrotic tissue may be sloughed off, and the diagnosis can sometimes be made by finding piece of renal medullary tissue in the urine. Pyelography may demonstrate cavities and sinuses in the resion of papillae. Anuria & oliguria can lead to the acute renal failure, and especially prognosis and progress may be affect influenced by urinary infection. We report a case of renal papillary necrosis with ingestion of bear gallbladder. On pyelography, Persistent contrast is diagnostic clue of renal papillary necrosis. This case is not be related to urinary tract infection, but occurred acute renal failure. Expectant treatment was gone.

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.

악성 점막하 종양과의 구별이 어려웠던 Gastritis Cystica Profunda 1예

선제형,박진석,한민석,김수항,김우진,박인형,이숭,유종선,박찬국 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.3

Gastritis cystica profunda (GCP) is a rare disease characterized by gastric foveolae elongation along with hyperplasia and cystic dilatation of the gastric glands extending into the tissue beneath the submucosa. GCP mainly develops at the gastroenterostomy stoma but can arise in a stomach that has not undergone surgery. The proposed pathogenesis is related to chronic inflammation, ischemia and the presence of a foreign body. GCP may present as a submucosal tumor, Polyp or a giant gastric mucosal fold. Endoscopic ultrasonography (EUS) is an effective diagnostic method for differentiating GCP from protruding and elevated gastric lesions. We report a case of GCP along with the endoscopic and EUS findings that were indistinguishable from a malignant submucosal tumor.