Study on the Elastic Characteristics of Living Cells using Atomic Force Microscope Indentation Technique

Kwon Eun-Young,Kim Young-Tae,Kim Dae-Eun Korean Tribology Society 2006 KSTLE International Journal Vol.7 No.1

In this work, imaging and study of elastic property of the living cell was performed. The motivation of this work was to seek the possibility of exploiting Young's modulus as a disease indicator using Atomic Force Microscope (AFM) and also to gain fundamental understanding of cell mechanics for applications in medical nanorobots of the future. L-929 fibroblast adherent cell was used as the sample. Imaging condition in cell culturing media environment was done in very low speed ($20{\mu}m/ s$) compared to that in the ambient environment. For measuring the Young's modulus of the living cell, AFM indentation method was used. From the force-distance curve obtained from the indentation experiment the Young's modulus could be derived using the Hertz model. The Young's modulus of living L-929 fibroblast cell was $1.29{\pm}0.2$ kPa.

Study on the Elastic Characteristics of Living Cells using Atomic Force Microscope Indentation Technique

Eun-Young Kwon,Young-Tae Kim,Dae-Eun Kim 한국트라이볼로지학회 2006 KSTLE International Journal Vol.7 No.1

In this work, imaging and study of elastic property of the living cell was performed. The motivation of this work was to seek the possibility of exploiting Young’s modulus as a disease indicator using Atomic Force Microscope (AFM) and also to gain fundamental understanding of cell mechanics for applications in medical nanorobots of the future. L-929 fibroblast adherent cell was used as the sample. Imaging condition in cell culturing media environment was done in very low speed (20 μm/s) compared to that in the ambient environment. For measuring the Young’s modulus of the living cell, AFM indentation method was used. From the force-distance curve obtained from the indentation experiment the Young’s modulus could be derived using the Hertz model. The Young’s modulus of living L-929 fibroblast cell was 1.29 ± 0.2 kPa.

AFM indentation 기법을 이용한 세포의 탄성특성에 관한 연구

권은영(Eun-Young Kwon),김영태(Young-Tae Kim),김대은(Dae-Eun Kim) 한국트라이볼로지학회 2006 한국트라이볼로지학회 학술대회 Vol.2006 No.6

In this work, imaging and investigation of elastic property of the living cell was performed. The motivation of this work was to seek the possibility of exploiting Young's modulus as a disease indicator using Atomic Force Microscope (AFM) and also to gain fundamental understanding of cell mechanics for applications in medical nanorobots of the future. L-929 fibroblast adherent cell was used as the sample. Imaging condition in cell culturing media environment was done in very low speed(20 ㎛/s) compare to that in ambient environment. For measuring the Young's modulus of the living cell, AFM indentation method was used. From the force-distance curve obtained from the indentation experiment the Young's modulus could be derived using the Hertz model. The Young's modulus of living L-929 fibroblast cell was 1.29 ± 0.2 kPa.

P087 : Adverse effects of oral cyclosporine in the treatment of various skin diseases

( Hyung Il Kwon ),( Eun Jin Kim ),( Hyun Woo Kim ),( Hyun Chul Park ),( Jeong Eun Kim ),( Joo Yeon Ko ),( Young Suck Ro ) 대한피부과학회 2013 대한피부과학회 학술발표대회집 Vol.65 No.2

Background: Cyclosporine (CS) has been used for various skin diseases including psoriasis and atopic dermatitis. However, dermatologists are reluctant to use CS in clinics because of the adverse effects. Objectives: To investigate the adverse effects of CS for dermatological uses. Methods: A retrospective study of 1,335 patients with CS treatment was performed. Results: 15.6% of patients showed adverse effects. Gastrointestinal (GI) symptoms were the most common adverse effect. Other adverse effects included hypercholesterolemia, hypertrichosis, headache, hypertension, hypertriglyceridemia in order of frequency. Hypercholesterolemia was more often in men, but GI symptoms and hypertrichosis in women. Hypercholesterolemia, hypertriglyceridemia and GI symptoms were more common in adults, but hypertrichosis in young. GI symptoms and headache occurred more often within three months of CS treatment, but hypertension, hypercholesterolemia and hypertriglyceridemia after three months. Hypertrichosis was more often in group with low initial dose. GI symptoms occurred more often with lower CS cumulative dose group and hypertension and hypertriglyceridemia in higher CS cumulative dose group. Conclusion: Comparing to previous studies, the frequency of adverse effects of CS was proven to be low. Therefore, in dermatologic field, we suggest that CS is relatively safe with periodic follow-up.

장기간 항갑상선제 투여 후 임의 중단 뒤 재복용시 발생한 무과립구증 1 예

김승만;김태영;박수영;배영환;서영경 정은주;김태균;권민정;박정현;이순희 인제대학교 2011 仁濟醫學 Vol.32 No.-

Agranulocytosis, one of the major side effects of antithyroid a gents, probably occurs in less than 0.25% of cases treated with antithyroid agents. It usually occurs within the first several weeks or months after the initiation of therapy, when drug dosage is higher. Most reported cases of agranulocytosis have occurred during the first 3 months of therapy. We describe here a rare case that did not experience the side effect for 6 years of antithyroid agent treatment but presented with agranulocytosis in one month after re-exposure. It suggests that the major side effect such as agranulocytosis can occur in patients who had undergone prior uneventful antithyroid drug therapy.

운동부하테스트에 따른 정상혈압자의 혈압상승도가 고혈압 발병요인에 미치는 영향

권은영,김정주,고인태 경희대학교 체육대학 한국체육과학연구소 2003 體育學論文集 Vol.31 No.-

It is well established that the elevation of systolic blood pressure during exercise is the risk factor for cardiovascular diseases. The objective of this study is to examine whether the elevation of systolic blood pressure during exercise is correlated with the pathogenesis of hypotension To fulfill this objective, this study assigned 31(46.2±7.0 yr) middle-aged women to low group(n=17) and high group(n=14) according to the criteria for the classification of hypertension(JNC-VI, 1997). Following this, this study analyzed cardiovascular factors(SBP, DBP, HR, VO₂, RER) and blood components(LDLC, HDLC, TC, TG, HDLC/LDLC). The results of the present study were as follows: (1) SBP was significantly increased at resting state, at 4 minutes, at 6 minutes and at endpoint(P<.05), (2) There was significant difference between SBPmax and SBPrest(P<.05), (3) DBP was significantly increased solely at resting state SBPmax (P<.05), (4) RER was significantly increased at 10 minutes. In addition, a statistical analysis revealed that SBPmax-SBPrest was significantly correlated with age(r=0.336), SBPmax(r=0.827) and DBPmax(r=0.335). In conclusion this study indicates that the monitoring of such cardiovascular indicators as SBP, DBP, HR, VO₂ and RER is essential in health promotion in patients with obesity or normal healthy people as weil as patients with hypertension.

Resin infiltration을 시행한 법랑질 초기 우식 병소의 특성

김은영,권민석,김신,정태성 大韓小兒齒科學會 2012 大韓小兒齒科學會誌 Vol.39 No.1

The concept of resin infiltration which was born in an innovative philosophy to arrest the incipient caries. However, the structural changes of resin infiltrated lesions have not yet explained completely. The liquid resin might contribute not only to maximizing the penetration but to deteriorating physical stability. This study was performed to examine some physical and histological features of resin infiltrated incipient carious lesions. With the specimen of resin infiltrated lesions, microhardness by nanoindentation in depth profile, morphology of resin tags were revealed after HCl dissolution, and degree of microleakage were assessed. The percentage of microhardness of surface layer and lesion body of untreated specimen to sound enamel was 64.6% and 24.6% respectively, while that of resin-infiltrated lesions was 72.1%, showing significant difference (p<0.05). The resin tags observed under SEM had relatively homogeneous length of 433(282~501) ㎛ on the average. Among 20 specimens for microleakage assessment, 13 specimens showed no leakage while 5 and 2 showed leakage into outer and inner half of lesion respectively. It was thought the infiltrant resin penetrates deeply and homogeneously into lesion body and improves its hardness with relatively good physical stability. 본 연구는 infiltrant resin을 침투시킨 초기 우식 병소의 특성을 평가하기 위해 법랑질의 깊이에 따른 경도를 측정하고, 병 소 내로의 레진 침투양상을 분석하며, 미세누출 정도를 관찰하여 다음의 결과를 얻었다. 건전 법랑질에 대한 초기 우식 법랑질의 경도 백분율은 표층(5~40 ㎛) 64.6%, 병소본체(60~350 ㎛) 24.6%였으며, infiltrant resin을 침투시킨 병소의 경도 백분율은 72.1%로 나타났다. 5~350 ㎛의 전 깊이에서, infiltrant resin을 침투시 킨 병소는 비처치 우식 병소보다 경도가 유의하게 높았지만 정상 법랑질에 비해서는 경도가 유의하게 낮았다(p<0.05). FESEM 관찰 결과 탈회된 법랑질 내부로 비교적 균일하게 침투한 레진 테그가 관찰되었으며, 침투깊이는 433 ㎛(282-501)로 측정되었다. 열순환 처리 후 13개의 치아에서 미세누출이 관찰되지 않았고, 5개에서 병소 외측 절반, 2개에서 병소 내측 절 반까지 미세누출이 관찰되었다.

한국의 재활의료 전달체계

권혁철,정영일,남은우 高神大學校 保健科學硏究所 1993 보건과학연구소보 Vol.3 No.-

This study was carried out for reorientation of Rehabilitation Service Delivery System (RSDS) through reviewing reference and observing field practice. The most important results are as follows: 1. The current rehabilitation facility for handicapped persons can be classified into four categories : (a) those for physically disabled persons, (b) those for mentally disturbed persons, (c) those for visually disturbed persons, and (d) those for acoustic and speech disturbed persons. The nationwide number of rehabilitation facilities is 101 of those, 43.5% is for physically disabled persons and 32.9% is for mentally disturbed persons. 2. A small number of circulating rehabilitation centers for physically disability are being run by comprehensive rehabilitation centers since 1992. 3. The hospitals are self-supporting only 20% of their operational costs, and the rest of the operational costs comes from federal tax(40%) and local tax(40%). 4. The number of handicapped persons in Taegu and Kyungpook province is estimated to be about 50,000, but only 20 percent out of them ws registered. The rehabilitation facilities located in this area receives 69% of their operational costs from central government. This figure is higher than the national average of 64.6%. 5. Although RSDS is different from other medical delivery system, nonetheless, it should be developed as a sub-system of national health care delivery system. Its development should also be in accordance with the need of local community. Therefore we suggest the development policy for the development of RMDS must consider the following points.; First, all rehabilitation-related medical systems should be integrated unde ra single comprehensive system so that handicapped persons may easily obtain better service available. Second, rehabilitation programs based on local community should be rejuvenated. In addition to in-patient service, development of intermediate facilities and programs connecting home and society should be encouraged. Third, rehabilitation medical services should be more specialized. Also, more emphasis should be given to team approach to rehabilitation medical services. Fourth, a comprehensive rehabilitation information system should be developed so that handicapped persons may have easy access to public welfare facilities, and the central government should formulate a comprehensive long-term plan for the rehabilitation system.

신경회로망 제어기를 이용한 PID 파라미터 추정에 관한 연구

權重東,裵銀敬,金恩基,全基英,李承桓,吳鳳煥,李勳九,金容珠,韓慶熙 明知大學校 産業技術硏究所 2006 産業技術硏究所論文集 Vol.25 No.-

In this paper, supposed to solve these problem to PID parameters controller algorithm using ANN. In the proposed algorithm, the parameters of the controller were adjusted to reduce by on-line system the error of the speed of IM. In this process, EBPA NN was constituted to an output error value of an IM and conspired an input and output. The performance of the self-tuning controller is compared with that of the PH) controller tuned by conventional method (Ziehler-Nichols). The effectiveness of the proposed control method is verified thought the Matlab Simulink and experimental results.

4종의 식품 부패 미생물에 대한 국내산 자생 식물 열매 추출물의 항균성 탐색

권민경,이해은,박주연,한영숙 동아시아식생활학회 2003 동아시아식생활학회지 Vol.13 No.5

To select new useful domestic plants with antimicrobial activities, thirty five samples of berry plant were distributed from Plant Diversity Research Center in Korea Research Institute of Bioscience and Biotechnolog. Their extracts with methanol were tested against Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, Listeria monocytogenes by paper disc method. The methanol extracts from Viburnum dilatatum, Viburnum erosum, Aralia continentalis, Camellia japonica, Acer trumcatam, Arasaema takesimense and Rhysocarpus intermedius were effective against S. aureus and the results were as follows: Viburnum erosum 6.5 ㎜, Viburnum dilatatum and Aralia continentalis 7.0 ㎜, Rhysocarpus intermedius 8.0 ㎜, Acer to mcatum 9.0 ㎜, Camellia japonica and Arisaema takesimense 9.5 ㎜ And only the methanol extract from Camellia japonica was effective against L. monocytogenes, 7.0 ㎜. Antimicrobial activities of E. coli and S. typhymurium were not detected. The minimum inhibitory concentration(NIC) of berry of Camellia japonica was examined as 1,250 ㎍/mL against S. aureus and as 1,250 ~ 2,500 ㎍/mL against L. monocytogenes.