• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.416-419
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• 1991

Effective micropropagation was achieved by axillary bud culture from stool shoots of 15-year-old Betula platyphylla var. japonica. Shoot development and proliferation from the explants were successful on WPM supplemented with 0.5 or 1.0mg/l BAP. All the regenerated shoots rooted when transfered to GD medium containing 0.2mg/l IBA. After transplaning to soil more than 95% of the plantlets survived and showed normal growth. The results demonstrate that masspropagation of selected mature trees is feasible using tissue culture technique.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.55-55
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• 2001

Erythropoietin(EPO)는 적혈구 세포 증식, 분화 및 생존에 있어서 가장 중요한 요인이다. 또한, 빈혈성저산소증에 있어서도 EPO가 중요한 역할을 한다고 알려져 있다. 태아에서 EPO 생산부위는 간이라고 알려져 있으나, 임신 120-140일에 신장으로 이동하기 시작하여 출생 후 약 40일경 이후에는 완전히 신장에서만 분비한다 EPO단백질의 분비는 오전 8시에 가장 낮고 오후 8시에 가장 높은 2중 리듬의 형태로 발현되어진다. EPO는 27개의 leader sequence와 165개의 아미노산으로 총 193개의 아미노산으로부터 분비된다. EPO단백질의 분자량은 18 kDa이나, 약 40%의 당쇄가 첨가되어있는 당단백질으로서 분자량은 30 kDa이다 N-linked 당쇄 3개(Asn-24, 38 및 83)와 O-linked 당쇄 1개(Ser 126)의 첨가부위가 존재하며, 2개의 disulfide bridges(7-161번, 29-33번)를 형성하고 있다. 이러한 당쇄의 수식은 EPO의 대사에 있어서 매우 중요하다. EPO를 가축의 소변으로부터 생산하기 위하여 생쥐의 3.6 kb UII promoter 하류에 genome hEPO와 SV 40 poly A를 연결하여 형질전환용 발현 벡터를 구축하였으며, 과배란 유기로 채란되어진 돼지의 1-세포기 수정란의 웅성전핵에 유전자를 미세주입기로 주입 후 즉시 대리모에 이식하였다. 66두에 미세주입된 1572개의 수정란을 외과적 방법으로 이식, 평균 23개의 수정란을 이식하였다. 생산된 자돈 112두중 2두(3-5, 3-15번)에서 PCR양성반응(304, 567bp)을 나타내어, 2두의 돼지로부터 소변을 회수하였다. 회수된 소변을 이용 Elisa방법으로 EPO를 분석한 결과 3-5번 돼지에서만 분만 후 지속적으로 EPO농도가 증가되었다. EPO의 최고농도는 1.1 IU/$m\ell$였으며, 이러한 결과는 CHO 세포에서의 500-1000 IU/$m\ell$의 생산량보다도 약 500-1000배정도 낮은 수준이었다. 이상을 종합하여 보면, 1) 가축에서도 생리활성물질을 소변에서 생산할 수 있는 UII promoter의 활용가능성을 제시하였으며, 2) 현재로서는 EPO의 발현량이 너무 낮아, 사용된 생쥐의 promoter를 보완할 필요성이 있다고 사료된다. 그러나, UII promoter를 이용하여 생리활성 물질을 생산할 수 있는 형질전환 돼지 생산의 성공은, 앞으로 형질전환 가축을 이용하는 활용 면에서도 더욱 더 활발할 것으로 기대된다.

• Membrane Journal
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• v.14 no.2
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• pp.85-98
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• 2004

The situation of technology Predominance and the distribution of core technology were visually mapped thorough the investigation of technical trend during 20 years, which was provided with the analysis of patent information for the artificial skin. Therefore, it was expected that technology mapping by means of multilateral analysis method allowed a good grasp of current technology trend of the artificial skin and the subdivision into nation and a field of research presents the direction of R&D. In the early R&D stage of artificial skin, the preparation technology of filters implantable into the living body including nursing devices, bandages, and dressings or absorbent pads (A6IF-002/10) was on the rise in research field of artificial skin until 1980's. And then the materials technology for coating prostheses (A6l L-027/00)was leading the core technology of artificial skin. Also, Nowadays the fusion technology connected the material technology with the cultivation technology of undifferentiated human or animal cells/tissues including culture media (C l2N-005/00, C 12N-005/06) was highlighted all over the world.

• Journal of Chest Surgery
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• v.30 no.4
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• pp.357-362
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• 1997

In vivo testings of the monoleaflet polymer valve were performed in seven dogs to prove its blood biocompatibility. The monoleaflet polymer valve used in this study was developed for short-term usage n the ventricular assist device. The frame and leaflet of the polymer valve were made of polyurethane. The inter-aortic valved conduit were implanted in four dogs and the ventriculo-atrial valved conduit was implanted in one dog. The ventricular assist devices with polymer valve were implanted in two dogs. The longest survival was 20 days. Main causes of death were bleeding and infection. To examine the blood compatibility, each blood sample was collected and RBC, WBC, hematocrit, hemoglobin, platelet and lactic acid dehydrogenase were analyzed. These studies thus far demonstrated that, with further development, a reliable and inexpensive polymer valve will be used in the ventricular assist device as short term usage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.2
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• pp.57-64
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• 1980

Seed tunicates of Halocynthia roretzi (v. DRASCHE) which were artificially settled in Chungmu area were transplanted to Seonyudo and Eochungdo to know the feasibility of the tunicate culturing in the western coast of Korea. From April 1978 to March 1979, the growth of the transplanted tunicate in the two area was compared and analyzed in reference to the ecological factors. At the time when the seeds were transplanted, the mean body height of Halocynthia roretzi(V. DRASCHE) was 1.84 mm, body breadth 1.42 mm, and the body weight 15.0 mg. After 333 days the mean body height was 10.77 mm, body breadth 6.75 mm, and body weight 201 mg in Seonyudo area. In Eochungdo area the mean body height was 13.5 mm, body breadth 11.51 mu and body weight 880 mg. According to above results, it is possible to culture the seeds in Eochungdo area. Salinity $(29.2-32.0\%_{\circ})$ was favorable, water temperature $(6.8-26.8^{\circ}C)$ was not a critical factor, but the growth of the tunicate was affected by the high temperature$(over\;25.0^{\circ}C)$ in July. Transparency lower than 1.0 m seriously affects the growth of the tunicate, and it was one of the important factors inhibiting the growth of the tunicate. Seonyudo area was found out to be inadequate for the culture of the sea spuirt Halocynthie roretzi because of the retarded growth in body breadth and weight while showing extended growth in body length then leading to higher mortality owing to large amount of silting and fouling of the colonial tunicate, Didemnum (didemnum) moseleyi.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1119-1126
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• 1998

Background: In this study, we investigated the early time course of expression of the major histocompatibility(MHC) antigens, intercellular adhesion molecule-1(ICAM-1), vascular cell adhesion molecule-1(VCAM-1), interleukin-6 and the histopathological changes in the coronary arteries of cardiac allografts exchanged between inbred mice strains that differ in one loci of class I major histocompatibility antigen (B10.BR to B10.A). Material and Method: No immunosuppressive therapy was used. Both allografts and the hearts of the recipients were harvested at 7(group 1, n=6), 15(group 2, n=6), 21(group 3, n=6), and 30(group 4, n=6) days after transplantation. They were examined by immunohistochemistry, microscopy and morphometry. All allografts had contractions at the time of harvest. Result: A strong MHC class I antigen expression was present on the endothelial and medial cells of the coronary arteries in group 1 and remained unchanged in the rest of the groups. However, MHC class II reactivity was none or very little at any time. Mild to moderate ICAM-1 expression was observed on the endothelial cells, but not on the medial cells at any time by 30 days. VCAM-1 expression was strong both on the endothelial and medial cells at any time. Moderate degree expression of interleukin-6 was observed from 7 to 30 day specimens. Histopathologically, percentage of affected vessels(vessels with intimal thickening) was less than 10 % in 7 day group and increased up to 50 % at 30 days. Mean percent narrowing of the lumen of the affected vessels revealed less than 20 % at 7 days and 40 % at 30 days. The area occupied by tropomyosin positive cells in the intimal lesion, graded from 0 to 3, showed gradual increase but remained between grade 0 to 1 by 30 days. Medial integrity was also well preserved at any time. Moderate perivascular mononuclear cell infiltration was observed at 7 days and it was progressively increased upto 30 days. Recipients' heart revealed no positive immunopathologic findings. Conclusion: In this study, the early time course of progression of the transplantation vasculopathy was demonstrated in the murine heterotopic heart transplant model.

• Asian Journal of Turfgrass Science
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• v.21 no.1
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• pp.23-37
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• 2007

This study was carried out to investigate the characteristics of root growth in Kentucky bluegrass sod(KBS) and creeping bentgrass sod(BGS) transplanted in summer(August 9) and fall(September 19), respectively. Hydroponic system was also used to observe rooting development in the study. Root development differed in KBS by transplanting time. It reached to more than 5 cm after 100 days In summer and 50 days in fall. However, BGS's root grew over 6cm after 40 days, regardless of the season. There was no significant differences in BGS, regardless of any cutting treatment. In the case of KBS, it was best with sod culled with 0.5cm deep and 1.5cm long. But it grew beyond 5 cm in root growth under any treatment after 40 days in transplanting. In a hydroponic study, BGS produced root over 100cm for 80 days through a summer season. However, the root of KBS did only grow in condition below $20^{\circ}C$. These results indicated that root growth characteristics were variable in BGS and KBS. It was considered that rooting development of BGS might be improved with sufficient irrigation in summer, and KBS grows well in lower temperature of $10{\sim}18^{\circ}C$, as compared with BGS. As to establishing the lawn with a sodding method, it should be careful in transplanting time, especially KBS.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.10.3-11
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• 1982

Recently through the advancement of medical and surgical managements and the development of low pressure cuffed endotracheal tube, incidence of tracheal stenosis was decreased significantly. Though its incidence was decreased markedly, stenosis was developted unfortunately in the situations such as long term use of respirator, heavy infection, trauma of the trachea and long term intubation etc. Tracheal stenosis had been handled with various methods such as mechanical dilatation, tissue graft techniques, luminal augumentation and end to end anastomosis due to their individual advantages but their effects were not satisfactory. In 1959 Lester had been found the regenerated cartilage from the perichondrium of the rib incidentaly. Since then Skoog, Sohn and Ohlsen were reported chondrogenic potential of perichondrium through the animal experiments. Though many different materials have been tried to rebuild stenosis and gaping defect of trachea, tracheal reconstruction has been a perplexing clinical problems. We choose the perichondrium as the graft material because cartilage is the normal supporting matrix of that structure and it will be an obvious advantage to be able to position perichondrium over a defect and obtain new cartilage there. The young rabbits, which were selected as our experimental animals, were sacrified from two to eight weeks after surgery. The results of our experiment were as follows; 1) In control group, the defect site of trachea was covered with fibrosis and vessels but graft site was covered with hypertrophied perichondrium and vessels. 2) Respiratory mucosa was completely regenerated in defect sites both control and grafted groups. 3) The histologic changes of the grafted sites were as follows: 2 weeks- microvessel dilatation, inflammatory reaction, initiation of fibrosis 4 weeks- decreased microvessel engorgement, submucosal fibrosis, decreased inflammatory reaction immatured cartilage island was noted in the grafted perichondrium (one specimen) 6 weeks- mild degree vascular engorgement submucosal fibrosis. chronic inflamatory reaction cartilage island and endochondrial ossification was noted in the grafted perichondrium (Two specimens) 8 weeks- minute vascular engorgement dense submucosal fibrosis. loss of inflammatory reaction. cartilage island was noted in the grafted perichondrium (two specimens) 4) There was no significant differences in regeneration between active surface in and out groups. 5) We observed immatured cartilage islands and endochondrial ossification in the perichondrial grafted groups where as such findings were not noted in control groups except fibrosis. We concluded that perichondrium was the adequate material for the reconstruction of defected trachea but our results was not sufficient in the aspect of chondrogenic potential of perichondrium. So further research has indicated possibility of chondrogenic potential of perichondrium.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.147-148
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• 2003

동해안의 강릉 연안에 자생하는 토종 다시마인 개다시마는 산업적으로 개발의 여지가 매우 크다. 그러나 천연 자원량에 의존하고 있는 가공산업은 해황에 따라 원료 공급이 좌우되는 불안정성을 가지고 있어서 이 식물의 산업적 생산량을 확보하기 위한 방안으로 대량양식의 필요성이 대두되고 있다. 본 연구는 동해안 토종 다시마인 개다시마의 종묘생산기술 개발을 위해서 항온배양기와 실내수조배양을 실시하고 바다 가이식 양성에 의한 환경적응성 실험을 수행하였다. 연구 방법은 2001년 10월에 강릉연안 수심 20m에서 분포하는 개다시마 군락의 모조로부터 유주자액을 받아 온도 5, 10, 15, 20, $25^{\circ}C$, 조도 40, 80, 120 $\mu$mol m$^{-2}$ s$^{-1}$의 조건에서 6주간 정치배양하였다. 유주자의 발아 및 아포체 생장 실험 이후 바다 가이식 및 양성실험은 2002년 1~2월까지 1개월간 실시하였다. 유주자의 발아 및 아포체 형성은 1$0^{\circ}C$, 120$\mu$mo1 m$^{-2}$ s$^{-1}$에서 배양 2주만에 가장 먼저 아포체의 발아가 관찰되었으며, 이후 15$^{\circ}C$와 5$^{\circ}C$에서 순차적으로 아포체의 발아가 이루어졌다. 2$0^{\circ}C$는 80, 120$\mu$mol m$^{-2}$ s$^{-1}$에서 소수의 아포체만이 관찰되었으며, $25^{\circ}C$에서는 아포체가 형성되지 않았다. 아포체는 1$0^{\circ}C$에서 가장 좋은 생장을 보였고, 15$^{\circ}C$와 1$0^{\circ}C$에서는 비슷한 생장을 나타냈으며, 2$0^{\circ}C$에서는 80$\mu$mol m$^{-2}$ s$^{-1}$에서만 아포체의 형성이 관찰되어 가장 낮은 생장을 보였다. 동일 온도에서는 조도에 따른 생장의 차이가 많이 났는데, 40$\mu$mol m$^{-2}$ s$^{-1}$에서 가장 좋은 생장을 나타냈다. 80과 120$\mu$mol m$^{-2}$ s$^{-1}$에서는 120$\mu$mol m$^{-2}$ s$^{-1}$이 약간 좋은 생장을 보였지만 큰 차이는 나지 않았다. 생장이 가장 좋은 조건은 1$0^{\circ}C$, 40$\mu$mol m$^{-2}$ s$^{-1}$으로 엽장 1.28mm까지 생장했다. 전체적으로 수심이 깊은 곳에 서식하는 특성상 저수온과 저조도에서 좋은 생장 경향을 보였다. 실내배양을 통해 얻은 엽장 약 1~2mm의 종묘를 2002년 1월말에 삼척 호산에 위치한 바다 양성장에서 종묘들과 함께 2주간 수심별로 가이식(수온 12$^{\circ}C$)을 실시한 결과, 수심 1m에서 좋게 나타나 엽장이 약 5mm정도 생장하였다. 수심 0m에서는 강한 조도에 의해 엽상체가 사그라드는 기형이 나타났으며, 수심 5m에서는 엽상체의 기형이나 생장의 차이는 없었지만, 색택이 약간 바랜 것을 볼 수 있었다. 종합적으로 볼 때 종묘의 관리나 생장에는 수심 1~2m가 양호할 것으로 생각된다. 바다 가이식을 통해 엽장 5mm의 종묘로 생장시킨 후 바로 본양성장에 씨줄감기를 하여 양성을 실시하였다 양성 1개월 후 엽상체는 약 2~3cm, 최대 4~5cm까지 생장하였다. 이를 통해 강릉연안 토종 다시마인 개다시마에 대한 종묘 생산과 대량 양성의 가능성을 확인하였다.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.307-314
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• 2004

Xenotransplantation of porcine organs has the potential to overcome the severe. shortage of human tissues and organs available for human transplantation. The swine represents an ideal source of such organs because of their plentiful supply and their numerous anatomical and physiological similarities to the human. However, this procedure also carries with a number of safety issues relating to the zoonotic infections. Porcine endogenous retrovinJses(PERVs), \Wich are germ line transmitted and persist without symptoms in the pigs, are most concerning zoonotic viroses. In order to analyze the prevalence of PERV in domestic pigs, four kinds of pigs'(Landrace, Berkshire, Yorkshire, and Duroc) genomic DNA were isolated from their hair follicles. PCR analysis was carried out for detection of PERVs using subgroup A/B/C and E pol sequence primers. All pigs (20 heads) tested had high copy number of PERVs within genomes. Subgroup A/B/C and E pol gene sequences from 20 isolates were determined by direct sequencing. Sequence analysis showed pol sequences are highly conserved among intra- and inter-subspecies(99.l and 98.8%, respectively). As a first report of PERV prevalence in Korea pigs, our data would be the basic concepts of PERV transmission study in xenotransplantation.