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.

만선신부전 환자에서 관상동맥조영술 소견에 관한 연구

한대희,김성구,박상호,김성한,조원영,방덕원,조윤행,정의룡,은영근,권영구 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

Background : Patients with chronic renal fialure have a substantially elevated risk of death from cardiovascular diseases than do the general population. the patients with chronic renal failure are at significantly increased freqeuncy of hypertension, hyperlipidemia, and diabetes mellitus which are known to the risk factors of the coronary artery diseases, and the prevalence of the coronary artery diseases in chronic renal failure patients is highly associated with the hemodynamic disorder and metabolic abnormalities. therefore we expected that the coronary angiographic findings in patients with chronic renal failure should be different from the general population (control groups) and investigated the risk factors contributing to coronary artery diseases. Method : we have retrospectively compared the coronary angiographic findings of 44 patients with chronic renal failure on hemodialysis with that of 88 patients in the general population and investigated the factors contributing to the development and acceleration of coronary artery diseases in patients with chronic renal failure Result : Hypertension and diabetes mellitus which is risk factors for coronary artery disease is significantly increased in patients with chronic renal failure, in coronary angiographic finding the severity of the lesion is worse. the incidence of PCI or CABG of patients with chronic renal failure is more than that of control group but statistically no difference between patients with chronic renal failure and control group. the sex, the duration of disease, the duration of dialysis, serum creatinine in patients with chronic renal failure have no correlation to the prevalence of coronary artery disease and severity of lesion. hyperglycemic patients with chronic renal failure have high incidence of coronary artery disease and are worse in the severity of lesion Conclusions : There is significantly increased the pevalence and severity of involving multiple coronary artery diseses in hyperglycemic patients with CRF.

Aspirin 長期投與에 依한 胃粘膜細胞의 微細構造 變化

權英大,李東久 慶北大學校 醫科大學 1981 慶北醫大誌 Vol.22 No.1

흰쥐를 實驗動物로 하여 aspirin의 常用治療量인 體重 ㎏ 當 60㎎을 15日 및 30日間 經口投與하고 胃粘膜細胞에 일어나는 變化를 微細形態的으로 觀察한 結果를 要約하면 다음과 같다. 胃粘粘膜細胞中 가장 甚하게 損傷받는 細胞는 壁細胞와 主細胞로서 壁細胞에서는 SER과 intracelular canaliculi의 增殖이 그리고 主細胞에서는 RER의 斷裂, 擴張 및 酵素原顆粒數의 減少와 構造的 多樣性等의 變化가 投與期間에는 큰 差異없이 30分째에서 주로 나타났으며 1日째부터 약간씩 輕減되어 3日後에는 거의 回復하였다. 粘膜細胞, 粘膜頸細胞 및 argentaffin 細細에는 比較的 輕한 變性變化로서 이들 細胞들은 aspirin에 어느程度 抵抗이 있는 것으로 생각되었다. This study was made to clarify ultrastructural changes of gastric mucosal cells of rat with oral administration of aspirin, 60㎎ per ㎏. of body weight, for 15 and 30 consecutive diys. The following results were obtained: Parietal cells and chief cells out of the gastric mucosal cells were more severely injured: Parietal cells showed proliferation of SER and intracellular canaliculi, and chief cells showed fragmentation and dilatation of RER and decrease in number and disfiguration of zymogen granules. These changes were marked in 30 minutes after administration and slightly diminished in Ⅰ day and almost restored in 3 days. Mucous cells, mucous neck cells and argentaffin cells revealed relatively mild degenerative changes, and it speculated that these cells have somewhat resistance to aspirin.

mRNA의 3' end processing에 대한 mRNA 중합요소 인산화의 영향

권대환,박재현,송영하,안성훈 한양대학교 이학기술연구소 2006 이학기술논문지 Vol.9 No.-

RNA 중합효소의 C-terminal은 YSPTSPS의 반복적인 아미노산 서열을 갖고 있으며, 이들의 인산화는 전사의 개시, 중합, 또는 종결단계에 중요하다고 알려져 있다. 본 연구에서는 이러한 RNA 중합효소의 인산화가 mRNA의 3' end processing에 미치는 영향을 조사하였다. C-terminal domain (CTD) of RNA polymerase Ⅱ contains a repeated heptameric sequence (YSPTSPS) which is phosphorylated at serine 2 and 5. Phosphorylation of CTD in elongating RNA polymerase Ⅱ has been suggested to play a role in transcriptional initiation, elongation or termination. In the present study, we investigated the effect of RNA polymerase Ⅱ CTD phosphorylation on the 3' end processing of mRNA.

MedisGroups를 이용한 관상동맥우회술의 중증도 보정사망률에 관한 연구

권영대 한국의료QA학회 2000 한국의료질향상학회지 Vol.7 No.2

Background : Among 'structure', 'process' and 'outcome' approaches, outcome evaluation is considered as the most direct and best approach to assess the quality of health care providers. Risk-adjustment is an essential method to compare outcome across providers. This study has aims to judge performance of hospitals by severity adjusted mortality rates of coronary artery bypass graft (CABG) surgery. Methods : Medical records of 584 patients who got the CABG surgery in 6 general hospitals during 1996 and 1997 were reviewed by trained nurses. The MedisGroups was used to quantify severity of patients. The predictive probability of death was calculated for each patient in the sample from a multivariate logistic regression model including the severity score, age and sex. For evaluation of hospital performance, we calculated ratio of observed number to expected number of deaths and z score [(observed number of deaths - expected number of deaths)/square root of the variance in the number of deaths], and compared observed mortality rate with confidence interval of adjusted mortality rate. for each hospital. Results : The overall in-hospital mortality was 7.0%, ranged from 2.7% to 15.7% by hospital. After severity adjustment the mortality by hospital was from 2.7% to 10.7%. One hospital with poor performance was distinctly divided from others with good performance. Conclusion : In conclusion, severity-adjusted mortality rate of CABG surgery might be applied as an indicator for hospital performance evaluation in Korea. But more pilot studies and improvement of methodologies has to be done to use it as quality indicator.

노선 상업지역의 입체적 공간 이용에 관한 연구 : 청주시를 대상으로 in case of Chongju

권상준,정대영 淸州大學校 都市·地域開發硏究所 1996 都市·地域開發硏究 Vol.2 No.-

This study finds the characteristics of the three dimensional land use of linear commercial areas in case of Chongju as follows: a. The activities are connected with other commercial functions and facilities, involved high rised buildings. b. The tendency of upper floored buildings could represent the preference of commerce and business activities to the denser land uses and the higher the buildings. c. The structure of the land uses in linear commercial areas shows the effective allocation and centralization of commercial activities. This findings suggest as follows: a. To enlarge the spatial structure for dense and compact land use. b. To allocate appropriately urb in functions to enforcing the urban locational service. c. To establish political strategy to solve the land use systemizing for the management and effectiveness.

중년 이후의 남성에 있어서 알콜 섭취가 C-reactive protein 및 관련인자들에 미치는 영향

권대근,성동진,김승권,송영주 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.6

The purpose of the present study was to investigate the effect of C-reactive protein level and related risk factors such as T-chol, TG, uric acid and albumin in middle-aged Korean men with the frequency of alcohol consumption. The subjects of the present study was 94 men of 50-years old ages men in Seoul, Korea. The subjects were classified into 3 groups by Frequencies of alcohol consumption as follows ; non-alcohol consumption group (NA), light alcohol consumption group(LA: once or twice per week), heavy alcohol consumption group(HA: drinks more than 3 times per week). The CRP and T-chol, level of HA group was higher than compared to NA group(p<.05). In terms of TG, UA and albumin concentration. there was no significant difference. however. the value of TG was slightly higher trend in the HA group. The relationship between CRP & TG, UA was shown to significantly inverse correlation and the relationship between CRP & albumin was shown to significantly reverse correlation(p<.001, respectively). From these results. there was suggested that CRP and related cardiovascular rise factors were increased with frequency of alcohol consumption and high level of blood CRP, TG, UA are potential risk factors of cardiovascular disease factors in middle-aged korean men.

말초혈액에서 Tg mRNA에 대한 역전사 중합효소 연쇄 반응법의 갑상선 재발암의 분자생물학적 진단

권성일,박기룡,김현영,신채희,임영찬,최영식,박요한,이강대,장희경,이재화,염하용 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.4

연구배경: 갑상선암은 다른 조직에 발생한 암에 비해 비교적 천천히 자라므로 대부분 예후가 양호하지만, 일부에서는 주위 조직으로 침윤하거나 혹은 원격 전이로 인하여 치명적인 결과를 초래할 수 있다. 갑상선전절제술 및 131^I 제거술 후 경과 관찰시 갑상선암의 재발과 전이의 진단에 있어 131^I 스캔과 혈청 Tg의 측정이 현재 임상에서 가장 많이 이용되고 있으나 이 방법에는 여러 가지의 결점이 있다. 최근 Tg mRNA에 대한 RT-PCR법을 이용한 여러 연구결과는 131^I 스캔과 혈청 Tg 측정의 결점을 보완할 수 있는 좋은 보조적인 진단법으로 이용할 수 있을 가능성을 제시하였다. 이에 말초혈액에서 측정한 Tg mRNA에 대한 RT-PCR법이 갑상선 절제술 및 방사성요드 치료 후 갑상선암의 재발 및 전이 유무의 진단에 유용한가를 알아보고자 이 연구 시행하였다. 방법: 분화된 갑상선암으로 진단된 후 갑상선전절제술을 시행받고 방사성요드 치료를 받은 환자 중 현재까지 한차례에 이상 추적 방사성요드 전신 스캔을 시행하고 추적관찰이 가능했던 유두선암 35예, 여포선암 5예를 대상으로 연구를 시행하였다. 대상군은 131^I 스캔 소견상 음성인 군(Group Ⅰ), 잔여조직이 있는 군(Group Ⅱ), 국소전이가 있는 군(Group Ⅲ), 및 원격전이 군(Group Ⅳ)으로 구분하였다. 정상 대조군은 갑상선질환이 없는 10예의 건강인으로 하였다. 대상환자의 말초혈액을 이용한 Tg mRNA에 대해 특이적인 primer를 이용하여 RT-PCR 및 nested RT-PCR을 시행하였다. 결과: 본 연구 결과는 다음과 같다. 1) 131^I 스캔 소견상 음성인 군 21예 중 1예에서 Tg가 양성소견을 보였다. Anti Tg Ab가 양성인 4예 모두 Tg가 음성을 보였다. 잔여조직이 있거나 국소전이 및 원격전이를 보인 군 19예 중 Tg가 양성인 경우는 4예였으나, Tg mRNA는 전예에서 양성이었다. 2) 131^I 스캔에서 국소 및 원격전이 소견을 보인 8예 중 4예에서 Tg가 음성으로 131^I 스캔과 혈청 Tg 사이에 불일치 소견을 보였다. 3) 말초혈액에서 특이적인 primer를 이용하여 RT-PCR 및 nested RT-PCR을 시행한 결과 대상군 40예 및 정상 대조군 10예 모두에서 Tg mRNA가 양성을 보였다. 결론: 본 연구에서 갑상선 절제술 및 방사성요드 치료 후 갑상선암의 재발 및 전이 유무를 평가함에 있어 역전사 중합효소 연쇄 반응법을 이용한 Tg mRNA 측정의 의의는 재평가되어야 한다고 생각된다. Background: Differentiated thyroid cancer is the most common endocrine malignancy. Despite advances in the treatment of thyroid cancer, disease recurrence and metastasis may occur in as many as 20% of patients, and so continues to pose major problems in its clinical management. Serum thyroglobulin (Tg) measurements, by immunoassay, are used to detect residual or recurrent thyroid cancer following thyriod ablation. However, the usefulness of immunoassay is limited by both the requirement for thyroid hormone withdrawal, to attain optimal test sensitivity, and interference by the antithyroglobulin antibody (Anti-Tg Ab). Recent studies have reported the clinical usefulness of reverse transcription-polymerase chain reaction (RT-PCR) detection of Tg mRNA in the peripheral blood of patients with differentiated thyroid carcinomas. We performed this study to evaluated the usefulness RT-PCR of Tg mRNA in peripheral blood of patients with thyroid carcinoma following a total thyroidectomy and radioiodine ablation therapy. Methods: Forty cases that underwent a total thyroidectomy and radioiodine ablation therapy were included in this study. Of the 40 patients, 35 were papillary carcinomas and 5 were follicular carcinomas. Ten normal control subjects were also studied. Tg mRNA was extracted. Then RT-PCR and nested RT-PCR, were run with specific Tg primers. Concurrently, DNA sequencing of the isolates was carried out to prove the isolates were identical to the nucleotide sequence of the Tg. Results: The Tg was detected in 4 of 19 patients, with either a residual thyroid bed, or metastasis, on a 131^I whole body scan and in 1 of 21 patients with a negative radioiodine scan. Surprisingly, the Tg mRNA was detected in all the patients and normal controls. Conclusion: From our results we can not recommend Tg mRNA, detected by RT-PCR in peripheral blood, as a tumor marker superior to that of the Tg serum level. We consider an intensive re-evaluation of the method is required before considering its clinical applications (J Kor Soc Endocrinol 17:501∼513, 2002).