해마 theta리듬과 pyramidal neuron의 세포내 특성과의 상관관계

권오흥,조진화,남순현,김현정,최병주,김영진,이만기 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.4

Eledctrophysiological phenomena of pyramidal cells in the CAI area of the dorsal hippocampus were recorded from and filled with neurobiotin in anesthetized rats. The electropharmacological properties of membrane as well as the cellular-synaptic generation of rhythmic slow activity (theta)were examined. The intracellular response characteristics of these pyramidal cells were distinctly different from responses of inteneurons. Pyramidal cells had a high resting membrane potential, a low input resistance, and a large amplitude action potential. A afterhyperpolarization was followed a single action potential. Most of pyramidal cells did not display a spontaneous firing. Pyramidal cells displayed weak inward rectification and anodal break excitation. The slope of the frequency-current relation was 53.4 Hz/nA for the first interspike interval and 15.9 Hz/nA for the last intervals, suggesting the presence of spike frequency adaptation. Neurobiotin-filled neurons showed pyramidal morphology. Cells were generally bipolar dendritc processes ramifying in stratum lacunosum-moleculare, radiatum, and oriens. Commissural stimulation discharged pyramidal cells, followed by excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs). The frequency of theat-related membrane potential oscillation was voltage-independent in pyramidal neurons. At strong depolarization levels (less than 30 mV) pyramidal cells emitted sodium spike oscillation, phase-locked to theta. The observations provide direct evidence that theta-related rhythmic hyperpolarization of principal cells is brought by the rhythmically discharging interneurons. Furthermore, the findings in which interneurons were also paced by rhythmic inhibitory postsynaptic potentials during theta suggest that they were periodically hyperpolarized by their GABAergic septal afferents.

배양골세포 이식이 치조골재생에 미치는 영향

정순준,허익,박준봉,이만섭,권영혁 慶熙大學校 齒科大學 1995 慶熙齒大論文集 Vol.17 No.2

This study was performed to estimate the effects of cultured bone cell inoculated on porous type hydroxyaptite for the regeneration of the artificial alveolar bone defect. In this experiment 3 beagle dogs were used, and each of them were divided into right and left mandible. Every surgical intervention were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium (30mg/Kg). To reduce the gingival bleeding during surgery, operative site was injected with Lidocaine hydrochloride (1:80,000 Epinephrine) as local anesthesia. After surgery experimental animal were feeded with soft diet(Mighty dog, Frisies Co., U.S.A.) for 1 weeks to avoid irritaion to soft tissue by food. 2 months before surgery both side of mandibular 1st premolar were extracted and bone chips from mandibular body were obtained from all animals. Bone cells were cultured from bone chips obtained from mandible with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Porous type hydroxyapatite were immerse into the high concentrated cell suspension solution, and put 4 hours for attachment the cells on the surface of hydroxyapatite. Graft material were inserted on the artificial bone defect after 3 days of culture. Before insertion of cell-inoculated graft material, scanning electronic microscopic observation were performed to confirm the attachment and spreading of cell on the hydroxyapatite surface. 3 artificial bone defects were made with bone trephine drill on Abe both side of mandible of the experimental animal. First defect was designed without insertion of graft material as negative control, second was filled with porous replaniineform hydroxyapatite inoculated with cultured bone marrow cells as expermiental site, and third was filled with graft materials only as positive control. The size of every artificial bone defect was 3 mm in diameter and 3 mm in depth. After the every surgical intervention of animals, oral hygiene program were performed with 0.1% chlorhexidine digluconate. All of the animals were sacrificed at 2, 4, 6 weeks after surgery. For obtaining histological section, tissus were fixed in 2.5% Glutaldehyde and decalcified with Planko-Rycho Solution for 72 hr. Tissue embeding was performed in paraffin and cut parallel to the surface of mandibular body. Section in Bum thickness of tissue was done and stained with Hematoxylin-Eosin. All the specimens were observed under the light microscopy. The following results were obtained. 1. In the case of control site which has no graft material, less inflammatory cell infiltration and rapid new bone forming tendency were revealed compared with experimental groups. But bone surface were observed depression pattern on defect area because of soft tissue invasion into the artificial bone defect during the experimental period. 2. In the porous hydroxyapatite only group, inflammatory cell infiltration was prominet and dense connective tissue were encapsulated around grafted materials. osteoblastic activity in the early stage after surgery was low to compared with grafted with bone cells. 3. In the case of porous hydroxyapatite inoculated with bone cell, less inflammatory cell infiltration and rapid new bone formation activity was revealed than hydroxyapatite only group. Active new bone formation were observed in the early stage of control group. 4. The origin of new bone forming was revealed not from the center of, defected area but from the surface of preexisting bony wall on every specimen. 5. In this experiment, osteoclastic cell was not found around grafted materials, and fibrovascular invasion into regions with no noticeable foreign body reaction. Conclusively, the cultured bone cell inoculated onto the porous hydroxyapatite may have an important role of regeneration of artificial bone defects of alveolar bone.

충남서부지역의 콤바인 이용 및 구입성향조사

황성만,이승기,권순홍,유선대 공주대학교 자원과학연구소 2000 資源科學硏究論文集 Vol.8 No.-

The actual state of using, purchasing of combines have been investigated among the farmers who possess the three row and four row type combines of self thresher in Chung-Nam Province to present reasonable maintenance and utilization of combines. And then the condensed results are as follows. 1. It was found that 25.9% of surveyed farmhouses cultivated rice over 4.5ha which brings average income presented by the Department of Agriculture and Forestry. And 85.2% of farm houses had higher income than the national average 23,488,000 won in 1997. 2. It was surveyed that the working hours a day and working days a year are 9.26 hours and 19.2 days. And they have the charge of 22.8ha a year. 3. It was shown that the most frequent breakdowns happened to pretreating and reaping in 44.4% and the frequency of the annual repair and maintenance is 4.1 times. And they think the endurance years of 6.5 is proper. 4. It was surveyed that 33.3% of the farmers were motivated to buy combines for their own management and supporting others, 22.2% for the difficulties of timing, 9.3% of them for the possibility of purchasing in cheap price. 5. It was found that when they decided to buy combines, 61.1% of farm houses had experiences of analyzing for their management and 38.9% of them didn't. Also the more combines they purchase, the larger and higher qualities of combines they tend to choose. 6. It was shown that 25.9% of surveyed farmers were satisfied with their combines and 74.1% of them weren't. 47.5% of dissatisfaction resulted from high price, 27.5% from frequent breakdowns, 12.5% from rough after service. 7. I think it is necessary for the related authorities to give public information and education for maintenance, management analysis, keeping of combines to make farmers purchase and use them reasonably. Also overall supporting policies are needed for research and development of highly efficient combines and the ways of securing cultivating areas with the spread of large size combines.

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.

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.

Craniofacial surgery and the humanities

Kwon, Soon Man Korean Cleft Palate-Craniofacial Association 2019 Archives of Craniofacial Surgery Vol.20 No.2

Mode Ⅰ Field Intensity Factors of Infinitely Long Strip in Piezoelectric Media

Soon Man Kwon,Kang Yong Lee 대한기계학회 2000 KSME International Journal Vol.14 No.8

A Study on Tool Path Error Control for Disk Cams in a Five-Axis CNC Machining Center

Soon-Man Kwon,Joong-Ho Shin,Geun-Jong Yoo 제어로봇시스템학회 2004 제어로봇시스템학회 국제학술대회 논문집 Vol.2004 No.8

Dynamic Response of an Anti-plane Shear Crack in a Functionally Graded Piezoelectric Strip

Kwon, Soon-Man,Lee, Kang-Yong The Korean Society of Mechanical Engineers 2004 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.18 No.3

The dynamic response of a cracked functionally graded piezoelectric material (FGPM) under transient anti-plane shear mechanical and in-plane electrical loads is investigated in the present paper. It is assumed that the electroelastic material properties of the FGPM vary smoothly in the form of an exponential function along the thickness of the strip. The analysis is conducted on the basis of the unified (or natural) crack boundary condition which is related to the ellipsoidal crack parameters. By using the Laplace and Fourier transforms, the problem is reduced to the solutions of Fredholm integral equations of the second kind. Numerical results for the stress intensity factor and crack sliding displacement are presented to show the influences of the elliptic crack parameters, the electric field, FGPM gradation, crack length, and electromechanical coupling coefficient.

Near-Infrared Fluorescence Imaging Using a Protease-Specific Probe for the Detection of Colon Tumors

( Soon Man Yoon ),( Seung Jae Myung ),( Byong Duk Ye ),( In Wha Kim ),( Nam Gon Lee ),( Yeon Mi Ryu ),( Kyeong Soon Park ),( Kwang Meyung Kim ),( Ick Chan Kwon ),( Young Soo Park ),( Chan Sik Park ),( 대한소화기기능성질환·운동학회 2010 Gut and Liver Vol.4 No.4

Background/Aims: Early tumor detection is crucial for the prevention of colon cancer. Near-infrared fluorescence (NIRF) imaging using a target-activatable probe may permit earlier disease detection. Matrix metalloproteinases (MMPs) participate in tumorigenesis and tumor growth. The aim of this study was to determine whether NIRF imaging using an MMP-activatable probe can detect colon tumors at early stages. Methods: We utilized two murine colon cancer models: a sporadic colon cancer model induced by azoxymethane (AOM), and a colitis-associated cancer model induced by a combination of AOM and dextran sodium sulfate (DSS). Colonic lesions were analyzed by histologic examination, Western blotting, immunohistochemical staining, and NIRF imaging using an MMP-activatable probe. Results: Multiple variable-sized tumors developed in both models and progressed from adenomas to adenocarcinomas over time. At the early stage of the AOM/DSS model, diffuse inflammation was observed within the tumors. MMP expression increased progressively through normal, inflammation, adenoma, and adenocarcionoma stages. NIRF signal intensities were strongly correlated with each tumor stage from adenoma to adenocarcinoma. NIRF imaging also distinguished tumors from inflamed mucosa. Conclusions: NIRF imaging using a protease-activatable probe may be a useful tool for early tumor detection. This approach could translate to improve the endoscopic detection of colon tumors, especially in patients with inflammatory bowel disease. (Gut Liver 2010;4:488-497)