• Title/Summary/Keyword: On-resistance

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Ultra-Structures And $^{14}C$-Mannitol Transport Study of Human Nasal Epithelial Cells Using ALI Culture Technique (ALI 배양법 이용한 비강 점막 상피세포의 미세구조와 $^{14}C$-mannitol 투과도)

  • Kwak, Kyung-Rok;Hwang, Jee-Yoon;Lee, Ji-Seok;Park, Hye-Kyung;Kim, Yun-Seong;Lee, Min-Ki;Park, Soon-Kew;Kim, Yoo-Sun;Roh, Hwan-Jung
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.2
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    • pp.205-212
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    • 2001
  • Background : The information on nasal transport and the metabolism of peptides have been obtained from pharmacokinetic investigations in experimental animals. However, there are no transport and metabolic studies of human nasal epithelial cells. In this study, the permeability characteristics and the metabolic properties of in vitro human nasal cell monolayers were investigated. Material and Methods : Normal human inferior nasal conchal tissue samples were obtained from patients undergoing endoscopic nasal cavitary surgery. The specimens were cultured in a transwell using an air-liquid Interface (ALI) culture, and the transepithelial electrical resistance (TEER) value of the blank filter and confluent cell monolayers were measured. To determine the % leakage of mannitol, $4{\mu}mol%$ $^{14}C$-labelled mannitol was added and the % leakage was measured every 10 minute for 1 hour. Result : Human nasal epithelial cells in the primary culture grew to a confluent monolayer within 7 days and expressed microvilli. The tight junction between the cells was confirmed by transmission electron microscopy. The TEER value of the blank filter, fifth day and seventh day reached $108.5\;ohm.cm^2$, $141\;ohm.cm^2$ and $177.5\;ohm.cm^2$, respectively. Transcellular % leakage of the $^{14}$-mannitol at 10, 20, 30, 40, 50 and 60 minutes was $35.67{\pm}5.43$, $34.42{\pm}5.60$, $32.75{\pm}5.71$, $31.76{\pm}4.22$, $30.96{\pm}3.49$ and $29.60{\pm}3.68\;%$, respectively. Conclusion : The human nasal epithelial monolayer using ALI culture techniques is suitable for a transcellular permeability study. The data suggests that human nasal epithelial cells In an ALI culture technique shows some promise for a nasal transport and metabolism study.

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Mechanism of Growth Inhibition in Herbicide-Resistant Transgenic Rice Overexpressing Protoporphyrinogen Oxidase (Protox) Gene (Protoporphyrinogen Oxidase (Protox) 유전자 과다발현 제초제 저항성 형질전환 벼의 생육저해 기작)

  • Kuk, Yong-In;Shin, Ji-San;Yun, Young-Beom;Kwon, Oh-Do
    • Korean Journal of Weed Science
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    • v.30 no.2
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    • pp.122-134
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    • 2010
  • We investigated the levels of resistance and accumulation of terapyrroles, reactive oxygen species, lipid peroxidation, and antioxidative enzymes for reasons of growth reduction in herbicide-transgenic rice overexpressing Myxococcus xanthus, Arabidopsis thaliana, and human protoporphyrinogen oxidase (Protox) genes. The transgenic rice overexpressing M. xanthus (MX, MX1, PX), A. thaliana (AP31, AP36, AP37), and human (H45, H48, H49) Protox genes showed 43~65, 41~72 and 17~70-fold more resistance to oxyfluorfen, respectively, than the wild type. Among transgenic rice lines overexpressing Protox genes, several lines showed normal growth compared with the wild type, but several lines showed in reduction of plant height and shoot fresh weight under different light conditions. However, reduction of plant height of AP37 was much higher than other lines for the experimental period. On the other hand, the reduction of plant height and shoot fresh weight in the transgenic rice was higher in high light condition than in low light condition. Enhanced levels of Proto IX were observed in transgenic lines AP31, AP37, and H48 at 7 days after seeding (DAS) and transgenic lines PX, AP37, and H48 at 14 DAS relative to wild type. There were no differences in Mg-Proto IX of transgenic lines except for H41 and H48 and Mg-Proto IX monomethyl ester of transgenic lines except for MX, MX1, and PX. Although accumulation of tetrapyrrole intermediates was observed in transgenic lines, their tetrapyrrole accumulation levels were not enough to inhibit growth of transgenic rice. There were no differences in reactive oxygen species, MDA, ALA synthesizing capacity, and chlorophyll between transgenic lines and wild type indicating that accumulated tetrapyrrole intermediate were apparently not high enough to inhibit growth of transgenic rice. Therefore, the growth reduction in certain transgenic lines may not be caused by a single factor such as Proto IX, but by interaction of many other factors.

Differences between Species and Seasonal Changes in Cambial Electrical Resistance of Twenty Ornamental Tree Species (20개(個) 조경수종(造景樹種)의 형성층전기저항치(形成層電氣抵抗値)의 수종간(樹種間) 차이(差異)와 계절적(季節的) 변화(變化))

  • Lee, Kyung Joon;Han, Sim Hee;Jeong, Yong Seon
    • Journal of Korean Society of Forest Science
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    • v.86 no.4
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    • pp.415-421
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    • 1997
  • The objectives of this study were to obtain standardized basic data on cambial electrical resistance (CER) of ornamental trees to be used for estimation of tree vigor and to compare CER between shrubs, deciduous, and coniferous trees in relation to bud opening, flowering, and growth cessation. Eighty healthy trees with four trees each for twenty ornamental tree species growing at an university campus in Suwon were selected and their CER was measured using a Shigometer every week from March to May, once a month from June to October and every two weeks in November, 1996. The CER of all tree species was high in March, started to decrease in April, maintained minimum in May through August, began to increase in September, and returned in November to the similar high level to March. Among the 20 species, Metasequoia glyptostroboides showed the lowest($5.5k{\Omega}$) annual average CER, while Cercis chinensis and Ligustrum obtusifolium had the highest($22.7k{\Omega}$, $22.9k{\Omega}$) annual average CER. The lowest CER($2.4k{\Omega}$) in summer(June through August) was obtained from Wisteria floribunda, second lowest($2.5k{\Omega}$) from Metasequoia glyptostroboides, the highest CER($46.8k{\Omega}$) during dormant season from Euonymus japonica, and second highest($45.0k{\Omega}$) obtained from Ligustrum obtusifolium. The CER of most species, particularly shrub species, started to decrease with bud opening, and many species, particularly shrubs and deciduous trees with large amount of flowers, showed sharp decrease with flowering. When CER was compared between shrubs and trees, shrubs showed higher average CER than trees, and seasonal difference in CER of evergreen species was smaller than that of deciduous species. It is interesting to note that the deciduous Metasequoia glyptostroboides had the lowest annual average CER.

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Study for Clinical Characteristics of Nontuberculous Mycobacterial Pulmonary Diseases (폐 비결핵향산균종의 임상적 특징에 관한 연구)

  • Pae, H.H.;Lee, J.H.;Yoo, C.G.;Lee, C.T.;Chung, H.S.;Kim, Y.W.;Shim, Y.S.;Han, S.K.
    • Tuberculosis and Respiratory Diseases
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    • v.47 no.6
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    • pp.735-746
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    • 1999
  • Background: As the prevalence of nontuberculous mycobacteriosis has been increasing rapidly, there has been recent advance in diagnostic methods and drug therapies for disease. Although the incidence of pulmonary disease caused by nontuberculous mycobacteria(NTM) has been increasing in Korea since 1990, detailed clinical description about the disease were very few. In this study we described the clinical manifestations, radiologic findings, and therapeutic outcomes of nontuberculous mycobacterial pulmonary disease. Methods: Medical records and radiologic findings were retrospectively reviewed in 27 patients who were fulfilled the diagnostic criteria of ATS guideline for NTM pulmonary disease between January of 1990 and August of 1998 in Seoul National University Hospital(SNUH). Results: Of the 27 patients, 15 were male. The mean age was 51.5 yr($\pm$11.9). Twenty patients(74.1%) had preexisting pulmonary diseases. Among them, 19 patients had previous pulmonary tuberculosis. Sixteen patients(59.2%) had cavitary lesions and the majority showed slow progression over 1 yr during follow up period on radiography. Susceptibility test to standard antituberculous drugs showed 100% resistance to INH, 72.2% to RMP, 81.5% to EMB, 92.6% to PZA. The average resistance rate to 2nd-line antituberculous drugs was 66.1%. Among twenty-one patients(77.8%) who received drug therapy over 6 months, 11 subjects were improved and 10 subjects were aggravated. Of six subjects(22.2%) without therapy, 5 patients were aggravated. Presence of cavity and less than 3 sensitive drugs in the regimen were indicators for adverse outcome. Conclusion : The nontuberculous mycobacterial pulmonary diseases in our hospital developed predominantly in older patients with preexistent pulmonary disease. The results of antituberculous drug therapy has been frustrating and disappointing. To improve treatment response, different susceptibility tests and drug regimens for different species of NTM should be performed. Also, diagnostic and therapeutic guidelines of Korea should be made in the recent future.

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Selection of Virulent Isolates of Fusarium circinatum and Investigation of Pitch Canker Severity of Pinus rigida and P. rigida × P. taeda Seed Orchards in Jeju Island (제주도(濟州道) 리기다 및 리기테다 채종원(採種園)에서 푸사리움가지마름병 피해도(被害度) 조사(調査) 및 병원성(病原性) 균주선발(菌株選拔))

  • Woo, Kwan-Soo;Kim, Young-Joung;Kim, Tae-Su;Lee, Seong-Kyu
    • Journal of Korean Society of Forest Science
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    • v.94 no.6
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    • pp.402-409
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    • 2005
  • This study was undertaken to compare and estimate the severity of pitch canker of individual trees of Pinus rigida and Pinus rigida ${\times}$ P. taeda in two seed orchards in Jeju island, in which the orchards have been damaged by the pitch canker for seven years. Wind-pollinated two-year-old seedlings of P. rigida and P. rigida ${\times}$ P. taeda, in which the seedlings of P. rigida ${\times}$ P. taeda were from seeds of phenotypically selected, uninfected(but untested) trees, were inoculated with the pathogenic fungus, Fusarium circinatum, isolated from P. rigida and P. thunbergii. The virulence of the isolates was also identified. Statistically significant difference was found in 'stem cankers'(SC; ${\chi}^2=7.76$, P=0.05) among 4 plantations of P. rigida ${\times}$ P. taeda of two seed orchards. P. rigida was higher in 'top kill' (TK) and 'branch tip symptoms' (BT) than those of P. rigida ${\times}$ P. taeda. In artificial inoculation tests, mortality of the seedlings from the resistant candidates was 14% higher than that of the seedlings from the susceptible candidates. This result may becaused by unknown pollen trees and/or candidate tree selection based only on phenotype. Two of five fungal isolates, C-6-L(9) and C-6-L(19), showed significantly higher mortality (68% and 60%, respectively) than others, suggesting that these isolates can be used as virulent isolates for a mass artificial inoculation. Resistance candidate seedlings that were selected from this study can be utilized as useful materials for fundamental studies of genetics and biochemistry to breed resistance varieties to pitch canker.

The Analysis of Risk Factors of Pulmonary Tuberculosis Patients Failed in Retreatment (재치료실패 폐결핵 환자의 위험인자 분석)

  • Kim, Hyoung-Soo;Lee, Won-Jin;Kong, Seok-Jun;Shon, Mal-Hyun
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.6
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    • pp.684-690
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    • 2000
  • Background : The most common cause of treatment failure of pulmonary tuberculosis is early stoppage of treatment or irregular medication. The most important aspect of a retreatment is regular medication provided over a long period. Inadequate treatment may cause drug resistance and prolong the duration of chemotherapy. This study analyzed the risk factors of pulmonary tuberculosis patients, who failed in retreatment, and to use the results as basic data in the management of intractable tuberculosis patients with improving the rate of retreatment success. Methods : We performed a retroactive study of 62 pulmonary tuberculosis patients in retreatment at National Mokpo Tuberculosis Hospital from Jan. 1994 to Dec. 1995. The patients were separated into two groups: group I was retreatment failure and group II was retreatrnent success. For the analysis of risk factors in retreatment failure, we compared the difference between the two groups and tested the confidence limit about results of the results by independent t-test, ${\chi}^2$ test and Fisher's exact test. Results : The treatment failure rate of retreatment patients was 13(21%), and treatment success 49(79%). No significant difference (p>0.05)in age, sex, number of treatment, irregular rate of treatment, extent of the disease & cavitary lesion on the chest X-ray, number of resistance drugs, number of used drugs to medication, number of sensitive bactericidal drugs to medication, rate of sensitive drugs to medication and resisiance to INH & RFP had not significant difference. was found. However, the number of treatment was $2.4{\pm}0.8$ in group I and $1.6{\pm}0.9$ in group II, and had showing a significant difference(p<0.05) between the two groups. Conclusion : The risk factor of retreatment failure was more irregular previous treatment the irregularity of the previous treatment. For reducing the retreatment failure of pulmonary tuberculosis, greater efforts are needed more need to be done to prevent failure of first treatment.

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Evaluation of Potato Genetic Resources and Development of Potato Varieties with Diverse colors (감자 유전자원 평가 및 다양한 컬러 감자 품종 개발)

  • 임학태;이규화;구동만;양덕춘;전익조
    • Korean Journal of Plant Resources
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    • v.16 no.3
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    • pp.264-274
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    • 2003
  • Many potato genetic resources have been collected and improved for their diverse traits over the years using breeding program in KPGR. To select potential varieties for table and processing in Korea, 58 elite potato breeding lines and several 'Valley' varieties were cultivated and harvested at Korea Alpine area in 2001. The cultivated lines and varieties were evaluated using their cultural adaptability in the environment and tuber characteristics, such as the depth of tuber eye, tuber shape, skin color, flesh color, scab resistance, yield, and the resistance of hollow heart and internal brown spot disease. Additionally, in the selection of potential processing varieties, reducing sugar content (sum of glucose and fructose concentration) of tubers is critically considered, because it mainly influence on the chip color of processing potato tuber. For table stock varieties with white skin color, 'Early Valley', 'Summer Valley', 'Winter Valley', and 'Taebok Valley' were selected. In the aspect of diverse potato tuber color, several varieties were selected such as 'Golden Valley' for its yellow fresh and skin color, 'Gogu Valley', 'Juice Valley', and 'Rose Valley' for their red skin color, and 'Purple Valley' for its purple skin. Compared with world wide known processing cultivar 'Atlantic', 24 lines (or varieties) were selected for the potential potato processing industry due to their low reducing sugar contents (below 0.3%), high yield (above 4.0 ton/ha), and unique chip colors. Selected white chipping varieties were 'Taedong Valley', 'Kangshim Valley', and 'Kangwon Valley', which have 0.23%, 0.27%, and 0.29% of reducing sugar contents, respectively. 'Bora Valley', having deep purple color in both skin and fresh, was selected for purple chip variety and has 0.26% of reducing sugar content. Light yellow chip varieties (lines) were 'Rose Valley' and Valley 54, having 0.19% and 0.269% of reducing sugar content, respectively. For French frying potatoes, 'Stick Valley' of 0.22% and Valley 72 of 0.151% in reducing sugars were selected. All of these selected lines and 'Valley' varieties can be used as parents to improve potato genetic resources and to develop better varieties with unique traits and colors.

Characteristics of Flexible Transparent Capacitive Pressure Sensor Using Silver Nanowire/PEDOT:PSS Hybrid Film (은나노와이어·전도성고분자 하이브리드 필름을 이용한 유연 투명 정전용량형 압력 센서의 특성)

  • Ahn, Young Seok;Kim, Wonhyo;Oh, Haekwan;Park, Kwangbum;Kim, Kunnyun;Choa, Sung-Hoon
    • Journal of the Microelectronics and Packaging Society
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    • v.23 no.3
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    • pp.21-29
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    • 2016
  • In this paper, we developed a flexible transparent capacitive pressure sensor which can recognize X and Y coordinates and the size of force simultaneously by sensing a change in electrical capacitance. The flexible transparent capacitive pressure sensor was composed of 3 layers which were top electrode, pressure sensing layer, and bottom electrode. Silver nanowire(Ag NW)/poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) hybrid film was used for top and bottom flexible transparent electrode. The fabricated capacitive pressure sensor had a total size of 5 inch, and was composed of 11 driving line and 19 sensing line channels. The electrical, optical properties of the Ag NW/PEDOT:PSS and capacitive pressure sensor were investigated respectively. The mechanical flexibility was also investigated by bending tests. Ag NW/PEDOT:PSS exhibited the sheet resistance of $44.1{\Omega}/square$, transmittance of 91.1%, and haze of 1.35%. Notably, the Ag NW/PEDOT:PSS hybrid electrode had a constant resistance change within a bending radius of 3 mm. The bending fatigue tests showed that the Ag NW/PEDOT:PSS could withstand 200,000 bending cycles which indicated the superior flexibility and durability of the hybrid electrode. The flexible transparent capacitive pressure sensor showed the transmittance of 84.1%, and haze of 3.56%. When the capacitive pressure sensor was pressed with the multiple 2 mm-diameter tips, it can well detect the force depending on the applied pressure. This indicated that the capacitive pressure sensor is a promising scheme for next generation flexible transparent touch screens which can provide multi-tasking capabilities through simultaneous multi-touch and multi-force sensing.

Analysis of Environmental Design Data for Growing Pleurotus ervngii (큰 느타리버섯 재배사의 환경설계용 자료 분석)

  • Yoon, Yong-Cheol;Suh, Won-Myung;Lee, In-Bok
    • Journal of Bio-Environment Control
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    • v.14 no.2
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    • pp.95-105
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    • 2005
  • This study was carried out to file up using effect and requirement of energy for environmental design data of Pleurotus eryngii growing houses. Heating and cooling Degree-Hour (D-H) were calculated and compared for. some Pleurotus eryngii growing houses of sandwich-panel (permanent) o. arch-roofed(simple) type structures modified and suggested through field survey and analysis. Also thermal resistance (R-value) was calculated for the heat insulating and covering materials of the permanent and simple-type, which were made of polyurethane or polystyrene panel and $7\~8$ layers heat conservation cover wall. The variations of heating and cooling D-H simulated for Jinju area was nearly linearly proportional to the setting inside temperatures. The variations of cooling D-H was much more sensitive than those of heating D-H. Therefore, it was expected that the variations of required energy in accordance with setting temperature or actual temperature maintained inside of the cultivation house could be estimated and also the estimated results of heating and cooling D-H could be effectively used far the verification of environmental simulation as well as for the calculation of required energy amounts. When the cultivation floor areas are all equal, panel type houses to be constructed by various combinations of materials were found to by far more effective than simple type pipe house in the aspect of energy conservation maintenance except some additional cost invested initially. And also the energy effectiveness of multi-span house compared to single span together with the prediction of energy requirement depending on the level insulated for the wall and roof area could be estimated. Additionally, structural as well as environmental optimizations are expected to be possible by calculating periodical and/or seasonal energy requirements for those various combinations of insulation level and different climate conditions, etc.

Comparison of Pulsatile and Non-Pulsatile Extracorporeal Circulation on the Pattern of Coronary Artery Blood Flow (체외순환에서 박동 혈류와 비박동 혈류가 관상동맥 혈류양상에 미치는 영향에 대한 비교)

  • Son Ho Sung;Fang Yong Hu;Hwang Znuke;Min Byoung Ju;Cho Jong Ho;Park Sung Min;Lee Sung Ho;Kim Kwang Taik;Sun Kyung
    • Journal of Chest Surgery
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    • v.38 no.2 s.247
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    • pp.101-109
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    • 2005
  • Background: In sudden cardiac arrest, the effective maintenance of coronary artery blood flow is of paramount importance for myocardial preservation as well as cardiac recovery and patient survival. The purpose of this study was to directly compare the effects of pulsatile and non-pulsatile circulation to coronary artery flow and myocardial preservation in cardiac arrest condition. Material and Method: A cardiopulmonary bypass circuit was constructed in a ventricular fibrillation model using fourteen Yorkshire swine weighing $25\~35$ kg each. The animals were randomly assigned to group I (n=7, non-pulsatile centrifugal pump) or group II (n=7, pulsatile T-PLS pump). Extra-corporeal circulation was maintained for two hours at a pump flow of 2 L/min. The left anterior descending coronary artery flow was measured with an ultrasonic coronary artery flow measurement system at baseline (before bypass) and at every 20 minutes after bypass. Serologic parameters were collected simultaneously at baseline, 1 hour, and 2 hours after bypass in the coronary sinus venous blood. The Mann-Whitney U test of STATISTICA 6.0 was used to determine intergroup significances using a p value of < 0.05. Result: The resistance index of the coronary artery was lower in group II and the difference was significant at 40 min, 80 min, 100 min and 120 min (p < 0.05). The mean velocity of the coronary artery was higher in group II throughout the study, and the difference was significant from 20 min after starting the pump (p < 0.05). The coronary artery blood flow was higher in group II throughout the study, and the difference was significant from 40 min to 120 min (p < 0.05) except at 80 min. Serologic parameters showed no differences between the groups at 1 hour and 2 hours after bypass in the coronary sinus blood. Conclusion: In cardiac arrest condition, pulsatile extracorporeal circulation provides more blood flow, higher flow velocity and less resistance to coronary artery than non-pulsatile circulation.