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      • 냉동 제대혈 세포의 체외 증폭

        김삼용,김철희,배광봉,김현수,박상준,김종숙,윤환중,조덕연 충남대학교 암연구소 1998 癌共同硏究所 硏究誌 Vol.2 No.1

        Background : Cord blood(CB), which has no HLA restriction, is an alternative to bone marrow for hematopoietic stem cell transplantation. The use of cord blood, however, is limited by the number of progenitor/stem cells necessary to reconstitute the older child or adult. Therefore, ex vivo expansion of CB could have tremendous impact on diverse clinical settings. We studied the ex vivo expansion of isolated population of CD34_(+) cells from cryopreserved CB cells. Methods : CD34 cells were isolated from cryopreserved CB mononuclear cells. Purified cells were cultured with various combinations of hematopoietic growth factors including erythropoietin(EPO), stem cell factor(SCF), granulocyte-colony-stimulating factor(G-CSF), gra-nulocyte, macrophage-colony-stimulating factor(GM-CSF), interleukin-1β(IL-1β), 1L-3, and IL-6. After 7, 10 or 14 days of culture, the fold increases of colony-forming unit- granu-locyte, macrophage(CFU-GM), burst-forming unit-erythroid(BFU-E), colony-forming unit-mix (CFU-Mix), and high proliferative potential colony-forming cell(HPP-CFC) were evaluated. Results : Ten-day culture with the combination of EPO, SCF, G-CSF, IL-1β, and IL-3 resulted in a median of 60-fold increase of CFU-GM, which was greater than those with the combinations of less than 5 growth factors. The addition of IL-6 or GM-CSF to this combination did not enhance CFU-GM expansion. Ten-day culture was significantly superior to 7-day culture for CFU-GM expansion. Prolongation of culture to 14 days, however, revealed decreased expansion of CFU-GM compared to 10 days. BFU-E and CFU-Mix were expanded to 2~5 folds in 7-day culture with the combination of EPO, SCF, and G-CSF. Further expansion was not achieved in 10-day culture and colonies disappeared in 14-day culture. HPP-CFC was expanded to a median of 7.5 folds in 7-day culture with the combination of EPO, SCF, G-CSF, IL-1β, IL-3, and IL-6. Neither 10-day or 14 day-culture enhanced expansion of HPP-CFU. Conclusion : Cryopreserved cord blood cells maintain ex vivo expansion potential. In our system, 10-day culture with the combination consisting of EPO, SCF, G-CSF, IL-1β, and IL-3 seems to be adequate for hematopoietic progenitor/stem cell expansion from cryopreserved cord blood cells.

      • KCI등재후보

        위절제술 환자의 표준진료지침 개발 및 적용 효과

        김은희,김철규,이순교,김순덕,이혜옥,권정순,이경미,이민미,심순미,유용만,신종식,강은희,이상일,김병식,오성태,육정환,박수길 한국의료QA학회 2003 한국의료질향상학회지 Vol.10 No.2

        Background : Gastric cancer is the most common malignant tumor in Korea. surgical operation is one of the major treatment modalities for gastric cancer patients. Therefore, gastrectomy is one of the most common procedures in General Surgery. There were variation in length of hospital stay and medical treatment for gastrectomy between three surgeons at Asan Medical Center. Clinical pathways have received considerable attention as a tool for recucing the medical practice variation, increasing the efficiency of care process, and improving the quality of care. The aim of this study was to evaluate the effect of a clinical pathway for gastrectomy in gastric cancer patients. Methods : The clinical pathway for gastrectomy was developed and implemented by a multidisciplinary group in Asan Medical Center. A computerized clinical pathway program was developed and revised after a pilot test. A total of 145 patients underwent gastrectomy by three surgeons at Asan Medical Center. We compared the length of hospital stay, patient satisfaction, and unplanned readmission rate between the pre-pathway group(n=67) and the post-pathway group(n=78). We also investigated the degree of satisfaction among the physicians and nurses who were main end-users of the clinical pathway. Results : The clinical pathway was applied to all target patients. The average length of hospital stay was shortened from 12.7days to 10.6days(p<0.01). The degree of patient satisfaction with the care process changed from 90.3% to 89.2% after the implementation of the clinical pathway, but the difference was of satistically significant(p=0.761). Unplanned readmission rate was 2.9% in the pre-pathway group. More than 90% of physicians and nurses answered that the clinical pathway had been a useful tool in their medical practice. Conclusions : The findings of the study demonstrated that implementation of the clinical pathway for gastrectomy produced substantial reduction in the length of hospital stay while improving the quality of patient outcomes. The computerized clinical pathway program can be used as one of the powerful patient management tools for reducing the practice variations and increasing the efficiency of care process in Korea hospital settings.

      • KCI등재

        펄프지료의 pH가 고해에 미치는 효과

        김창락,문상환,김재옥,김철환,박종열 경상대학교 농업생명과학연구원 2003 농업생명과학연구 Vol.37 No.4

        펄프 섬유를 이용해서 종이를 제조하기 위해서는 반드시 섬유를 물에 현탁시키는 해리와 섬유 벽에 물리적 변화를 부여하는 고해의 과정을 거쳐야 하고, 이 과정에서 섬유는 팽윤 과정을 겪게 된다. 섬유가 물에 의해 팽윤이 잘 될수록 유연성이 좋아지기 때문에 종이의 물리적 성질이 훨씬 향상된다. 펄프를 물에 현탁시키는 전처리 과정에서 NaOH를 첨가하여 침지과정에서 섬유의 팽윤이 더 잘되게 하기 위함인데, NaOH의 처리량을 증가시킴에 따라 고행 동안 섬유벽의 팽윤이 촉진되어 종이의 강도적 성질이 향상되는 것을 확인할 수 있었다. Pulp fibers must be disintegrated and refined before papermaking. During refining, internal fibrillation of fiber walls are generated, leading to fiber wall swelling. Owing to improved fiber flexibility, strength properties of paper are remarkably improved. This study aimed to explore how NaOH addition to pulp suspension before refining would affect fiber swelling in addition to paper properties. As the addition ratio of NaOH increased, strength properties of paper were greatly improved due to the increase of fiber wall swelling. The extent of fiber wall swelling according to pH was observed by paraffin embedding and physical sectioning. In conclusion, it became evident that higher pH in fiber suspension gave positive contribution to fiber wall swelling during refining.

      • 단기배양을 통한 말초혈액 CD34 양성세포의 체외증폭

        박상준,김철희,배광봉,김현수,김종숙,윤환중,조덕연,김삼용 충남대학교 의과대학 지역사회의학연구소 1997 충남의대잡지 Vol.24 No.1

        Background: It is suggested that clinical practice in the areas of bone marrow transplantation and gene therapy might rely on the ex vivo expansion of hematopoietic stem/progenitor cells. However, the condition for ex vivo expansion of hematopoietic progenitor cells is not well established. The authors pursued a series of experiments to define the proper conditions for the expansion of hematopoietic cells in the short-term liquid suspension culture of mobilized peripheral blood CD34+ cells. Methods: 1.0ml cultures were initiated with 9×10^3 PB CD34+ cells, which were isolated from PB mononuclear cells (MNCs) by high-gradient cell sorting, in 12 well plates with the various combinations of hematopoietic growth factors(HGF). The following recombinant human HGFs were used: stem cell factor(SCF) 100ng/ml, granulocyte colony-stimulating factor(G-CSF) 100ng/ml, GM-CSF(granulocyte, macrophage colony-stimulating factor) 100ng/ml, interleukin-1 beta(IL-1B) 1ng/ml, interleukin-3(IL-3) 20ng/ml, interleukin-6 (IL-6) 100ng/ml. At the end of culture, colony-forming cells were evaluated by semisolid clonogenic assay. Results: 1) Using the high-gradient magnetic sorting system, CD34^+ cells were isolated with a yield of 40 3% 2) In 7 day culture of PB CD34^+ cells(9×10^3 cells), nucleated cells expanded mean 10×10^3(range, 9 to 20×10^3) with the addition of SCF alone, 35×10^3(range, 10 to 60×10^3) with SCF plus G-CSF plus GM-CSF, and 130×10^3(range, 40 to 300×10^3) with the combination of SCF, G-CSF, IL-1, IL-3, IL-6, GM-CSF. In 14 day culture, nucleated cells expanded 10×10^3 to 1,860×10^3 with combination of human hematopoietic growth factors. 3) In 10 day culture without medium change of PB CD34^+ cells, CFU-GM numbers expanded 16. 5 fold(range, 7 to 59 fold) with the addition of SCF plus G-CSF plus Il-1 plus IL-3, 31.3 fold(range, 20.5 to 101.1 fold) with the combination of SCF, G-CSF, IL-1, IL-3, GM-CSF. In 14 day culture with or without medium change of PB CD34^+ cells was inferior to 10 day culture for CFU-GM expansion. 4) There was no significant difference for CFU-GM expansion between five growth factors(SCF,G-CSF,IL-1,IL-3,GM-CSF) and six growth factors(five growth factors plus IL-6). Conclusion: The authors could confirm that short-term suspension culture of peripheral blood CD34+ cells could expand hematopoietic progenitor cells. Ten-day culture with medium change of CD34+ cells with the addition of five growth factors, i.e. SCF, G-CSF, IL-1B, IL-3, and GM-CSF, might be the most efficient in this system.

      • 불응성 자가면역질환에서의 자가조혈모세포이식

        민도준,양동원,민창기,김완욱,이상헌,박성환,김동욱,이종욱,조철수,민우성,김범생,김호연,김춘추 대한조혈모세포이식학회 2001 대한조혈모세포이식학회지 Vol.6 No.1

        배경: 기존의 치료에 불응하고 예후가 불량한 자가면역질환 환자들에게 최근 고용량 면역억제 및 조혈모 세포이식이 새로운 치료방법으로 대두되고 있다. 저자들은 다발성 경화증(multiple sclerosis, MS) 및 류마티스 관절염(rheumatoid arthritis, RA) 등 2명의 자가면역질환 환자들에서 자가조혈모세포 이식을 시행하였다. 방법: 말초혈액 조혈모세포 가동화를 위하여 cyclophosphamide (4 g/㎡) 및 granulocyte colony stimulating factor (10 g/kg/day)를 투여하였고, CD34+ 세포를 분리·채집 하였다, 이식 전처치로 MS 환자에서 BEAM 및 antihymocyte globulin (ATG) (3.75 mg/kg), RA 환자에서 fludarabine (180 mg/㎡), ATG (10 mg/kg)와 busulfan (8 mg/kg)을 투여하였다. 결과: 호중구 수가 500/㎕ 이상으로 회복되는 기간은 MS 환자에서 9일, RA 환자에서 15일이었다. 혈소판이 20.000/㎕ 이상으로 회복되는 가간은 RA 환자에서 9일 이었고, MS 환자에서는 혈소판 감소증이 발생하지 않았다. 비혈액학적 독성으로 MS 환자에서 WHO 1도의 오심 및 점막염이 관찰되었다. MS 환자는 이식 6개월 후까지 시력감소가 남아있었으나, 이식전에 관찰되던 감각이상 및 운동장애 등의 신경학적 이상 소견은 더 이상 관찰되지 않았다. RA 환자는 이식 1개월 후 관절 증상 및 검사소견의 호전을 보였다. 결론: 불응성 자가면역질환 환자에서 고용량 면역억제 및 조혈모세포이식은 적은 독성으로 높은 치료효과를 기대할수 있으며, 향후 이 시술의 임상적 의의를 규명하기 위하여 전향적이고 장기적인 연구가 필요할 것으로 사료된다. Background: High-dose immunosuppressive therapy followed by autologous hemathpoietic stem cell transplantation (HSCT) has been proposed as a new approach to treat severe, refractory autoimmune diseases. We describe two patients with refractory autoimmune diseases (one multiple sclerosis 〔MS〕and one rheumatoid arthritis〔RA〕) who underwent T-cell-depleted autologous peripheral bleed stem cell transplantation for the first time in Korea. Methods: We mobilized autologous stem cells with cyclophisphamide (4 g/㎡) and granulocyte colony-stimulating factor (10 ㎍/kg/day). Stem cells were enriched ex vivo using CD34-positive immunoselection and reinfused after high-dose chemotherapy with BEAM and antithymocyte globulin (ATG) (3.75 mg/kg) in MS, or fludarabine (180 mg/㎡), ATG (10 mg/kg) and busulfan (8 mg/kg) in RA. Results: The engraftment with an absolute nerutrophil count greater than 500㎕ occurred on day 9 in MS and 15 in RA, respectively. The time to nontransfused platelet count greater than 2.000/㎕ was 9 day in RA. MS patient did not show ant episode of thrombocytopenia. Regimen-related non-hematopoietic toxicity was minimal. For 6 months since HSCT, them patient with MS had been free from previously existed sensory and motor abnormalities except decreased visual acuity. Then patient with RA and only one tender joint and two mildly swollen joints with improvement in laboratory parameters at one month after HSCT. Conclusion: These results underscore the feasibility and potential efficacy of intensive immunosuppression followed by autologous HSCT for treatment of intractable autoimmune diseases. The durability of remission, however, remains to be clarified.

      • 상호상관 함수를 이용한 지중선로 고장점 추정

        朴星完,林泳範,鄭州桓,成洛煥,金喆煥,申明徹 成均館大學校 科學技術硏究所 1994 論文集 Vol.45 No.2

        This paper is intended as an investigation of fault location for underground line. Over the past few decades a considerable number of studies have been made on protection of underground line. However, these approaches require the interruption of electric power supply from source for fault location estimation. Therefore, we proposed fault location algorithm for underground line protection without interruption of electric power supply. Cross correlation function is used in this algorithm. Also, EMTP data is used to demonstrate the capability of the proposed fault location algorithm.

      • KCI등재후보

        구강악안면영역에서 발생한 편평상피세포암종세포주에서 상피성장인자수용체의 발현 및 돌연변이에 관한 연구

        김철환,김경욱 大韓顎顔面成形再建外科學會 2003 Maxillofacial Plastic Reconstructive Surgery Vol.25 No.2

        Carcinogenesis has been considered as multiple stage process of denaturation of gene which control regulation of cell growth. The growth and differentiation of oral mucosal cell is controlled by growth factors which regulate development and differentiation of cell and apoptosis. It is well known that cell growth is not prevented, and secretion or reaction of growth factors is disturded in head and neck carcinoma including oral carcinoma. The epidermal growth factor is a polypeptide with potent mitogenic activitly of 6,045 daltons which has been shown to involve nuclear differentiation by trigger a cascade of intracellular ionic change and morphological transformation that it bind with epidermal growth factor receptor in surface of cells and delivering signal to inside of cells. The epidermal growth factor receptor is 170-kDa transmembrance phosphoglycoprotein. The extracelloular domain is binding site of epidermal growth factor, and intracellular domain possesses intrinsic tyrosine kinase astivity,which the stimulation can lead to autophosphylation of epidermal growth factor receptor and sequences lead to phosphylation of target protein in case of epidermal growth factor bind with target cell surface recrptor. Inrecently, eapression of epidermal growth factor receptor has been detected in oral squamous cell carcinoma, and overexpression of it is proved, and possibility of early markers of carcinogenesis in head and neck is presented. The many studies for the expression of epidermal growth factor receptor and relationship between it and prognosis of malignancy in carcinoma of breast or stomach have documented. But, in oral squamous cell carcinoma, the study for difference of amplication and mutation of epidermal growth factor receptor gene between primary carcinoma and merastastic carcinoma is rare. For study on mRNA expression of epidermal growth factor receptor,normal human oral keratinocyte, and cell lines of primary and metastastic oral squamous cell carcinomas were cultured, and then, electrophresis and RT-PCR(Reverse Transcriotion-polymerase Chain Reaction)were oerformed. The results were obstained as follows: The mutation of mRNA of EGF receptor were not detected in all oral squamous carcinoma cell lines. The expression of EGF receptor in oral squamous cell lines expressed 3-7 times higher than that of normal human oral keratinocyte of cytoplasmic domain. and 2-3times higher in extracellular domain. the expression of EGF receptor of cytoplasmic domain more expressed than that of extracellular domain in primary squamous cell line. The expression of EGF receptor in metastastic carcinoma cell lines is similis\ar or underexpressed than that of normal human oral keratinocyte cell lines. the expression of EGF receptor in the primary carcinoma cell lines expressed 2-5 times higher than that of metastastic carcinoma cell lines. From the results obtained in this study, the mutation have not mRNA of EGF receptor in carcinoma cell lines, and EGF receptor was overexpresses in early stage of carcinogemesis, and cytoplasmic domain of EGF receptor have relation with carcinogenesis, and EGF receptor have no relation with metastasis.

      • 웨이브렛 변환을 이용한 Voltage Sag 검출

        金喆煥,高榮勳 성균관대학교 2002 학술회의지원논문목록집 Vol.2002 No.-

        Wavelet transform is a new method for electric power quality analysis. Several types of mother wavelets are compared using voltage sag data. Investigations on the use of some mother wavelets. namely Daubghies, Symlets, Coiflets, Biorthogonal, are carried out. On the basis of extensive investigations, optimal mother wavelets for the detection of voltage sag are chosen. The recommended mother wavelet is 'Dautechies 4(db4)' wavelet. 'db4', the most commonly applied mother wavelet in the power quality analysis, can be used most properly in disturbance phenomena which occurs rapidly for a short time. This paper presents a discrete wavelet transform approach for determining the beginning time and end time of voltage sags. The technique is based on utilising the maximum value of dl(at scale l) coefficients in multiresolution analysis(MRA) based on the discrete wavelet transform. The procedure is fully described, and the results are compared with other methods for determining voltage sag duration, such as the RMS voltage and STFT(Short-Time Fourier Transform) methods. As a result, the voltage sag detection using wavelet transform appears to be a reliable method for detecting and measuring voltage sags in power quality disturbance analysis.

      • KCI등재

        대유행 인플루엔자(H1N1 2009) 환자 가족에서 인플루엔자 (H1N1 2009) 검사 양성률

        김학령,전한호,김민,강철환,박경화 대한감염학회 2010 감염과 화학요법 Vol.42 No.2

        Background: Influenza transmission in households a subject of renewed interest especially in pandemic situation. We performed this study to investigate the laboratory-confirmatory rate in household contacts with index cases of pandemic influenza (H1N1 2009). Materials and Methods: For three months from 1 September and 29 November 2009, people who had a history of close contact with confirmed cases of pandemic influenza (index case) were recruited. The information on the study participants was collected using a standardized questionnaire. Presence of the pandemic influenza (H1N1 2009) infection was confirmed by real-time reversetranscription polymerase chain reaction (RT-PCR). Results: A total of 113 index cases and 141 household contacts were investigated. One hundred and four index cases (92.0%) were younger than 20 years. The median age of household contacts was 40 years. Twenty eight household contacts (19.8%) had acute respiratory illness (ARI). Overall, 10.6% of enrolled household contacts were positive in RT-PCR for pandemic influenza (H1N1 2009). The positive rate of household contacts with ARI was 25.0% and it was 7.1% in household contacts without ARI. The positive rate was significantly higher in children and young adults under 30 years (28.3%) compared with that in household contacts older than 30 years (8.3%). Conclusions: This results showed a significant role of mild symptomatic or asymptomatic pandemic influenza (H1N1 2009) patients as a virus carriers in households.

      • KCI등재

        효소 처리에 의한 섬유벽 변화의 정량적 연구

        김재옥,김철환,박종열,양재경 경상대학교 농업생명과학연구원 2002 농업생명과학연구 Vol.36 No.4

        지료 조성 공정의 리파이닝 처리 동안에 펄프 섬유에 가해지는 섬유 손상을 방지하기 위하여 효소 리파이닝을 실시하였다. 펄프 섬유에 대한 효소 처리 효과를 정량적으로 측정하고자 효소 처리된 펄프섬유를 공초점레이저현미경(CLSM)을 통하여 물에 팽윤된 섬유의 횡단면 영상을 얻은 후 내부 피브릴화 현상을 화상분석법을 통하여 정량적으로 정하였다. 셀룰라아제 효소가 처리된 섬유는 단섬유 발생, 미세분 형성 등과 같은 기계적 손상이 없이 섬유벽의 팽윤이 세포 내강(lumen)을 향하여 일어나는 것을 확인할 수 있었다. 결론적으로 CLSM과 화상분석을 통하여 효소를 이용한 펄프 섬유의 생물학적 처리는 리파이닝과 같은 기계적 처리를 대체함으로써 제지 공정의 개선과 종이 물성의 향상에 상당히 기여할 수 있음이 입증되었다. This study was carried out for determinating the behavior of enzyme toward internal structure of pulp fibers quantitatively. A commercial enzyme, cellulase, was treated to the radiata pine ECF pulp in New Zealand Differently from the previous studies, the visual observation by Confocal Laser Scanning Microscope(CLSM) and the measurement of cross-sectional dimension of pulp fibers in a wet state by image analysis were made. Through the image analysis, it became evident that fiber wall swelling after cellulase treatment on pulp fibers occurred toward fiber lumen. In addition, it was clearly seen that the increase in physical properties of paper was closely related to internal fibrillation by the cellulase. The pulp fibers treated by the enzymatic treatment could avoid mechanical damages like fiber shortening and fines formation. Thus it was proved that the biological treatment by enzyme on pulp fibers generated internal fibrillation of pulp fibers.

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