Y-27632 Induces Neurite Outgrowth by Activating the NOX1-Mediated AKT and PAK1 Phosphorylation Cascades in PC12 Cells

Y-27632 is known as a selective Rho-associated coiled coil-forming kinase (ROCK) inhibitor. Y-27632 has been shown to induce neurite outgrowth in several neuronal cells. However, the precise molecular mechanisms linking neurite outgrowth to Y-27632 are not completely understood. In this study, we examined the ability of Y-27632 to induce neurite outgrowth in PC12 cells and evaluated the signaling cascade. The effect of Y-27632 on the neurite outgrowth was inhibited by reactive oxygen species (ROS) scavengers such as N-acetyl cysteine (NAC) and trolox. Furthermore, Y-27632-induced neurite outgrowth was not triggered by NADPH oxidase 1 (NOX1) knockdown or diphenyleneiodonium (DPI), a NOX inhibitor. Suppression of the Rho-family GTPase Rac1, which is under the negative control of ROCK, with expression of the dominant negative Rac1 mutant (Rac1N17) prevented Y-27632-induced neurite outgrowth. Moreover, the Rac1 inhibitor NSC23766 prevented Y-27632-induced AKT and p21-activated kinase 1 (PAK1) activation. AKT inhibition with MK2206 suppressed Y-27632-induced PAK1 phosphorylation and neurite outgrowth. In conclusion, our results suggest that Rac1/NOX1-dependent ROS generation and subsequent activation of the AKT/PAK1 cascade contribute to Y-27632-induced neurite outgrowth in PC12 cells.ope

Expression of Bitter Taste Receptors in Human Nasal Respiratory Epithelium

The nasal cavity encounters various irritants during inhalation such as dust and pathogens. To detect and remove these irritants, it has been postulated that the nasal mucosa epithelium has a specialized sensing system. The oral cavity, on the other hand, is known to have bitter taste receptors (T2Rs) that can detect harmful substances to prevent ingestion. Recently, solitary chemosensory cells expressing T2R subtypes have been found in the respiratory epithelium of rodents. In addition, T2Rs have been identified in the human airway epithelia. However, it is not clear which T2Rs are expressed in the human nasal mucosa epithelium and whether they mediate the removal of foreign materials through increased cilia movement. In our current study, we show that human T2R receptors indeed function also in the nasal mucosa epithelium. Our RT-PCR data indicate that the T2R subtypes (T2R3, T2R4, T2R5, T2R10, T2R13, T2R14, T2R39, T2R43, T2R44, T2R 45, T2R46, T2R47, T2R48, T2R49, and T2R50) are expressed in human nasal mucosa. Furthermore, we have found that T2R receptor activators such as bitter chemicals augments the ciliary beating frequency. Our results thus demonstrate that T2Rs are likely to function in the cleanup of inhaled dust and pathogens by increasing ciliary movement. This would suggest that T2Rs are feasible molecular targets for the development of novel treatment strategies for nasal infection and inflammation.ope

(An) Analytical study of Evaluation criteria of Science skills in Elementary Schools

The present treatise is attempt to survey the researching process that science skill in eledmentary school aims at, to analyse exercise evaluation criteria which can measure attainment of aim of attitude and interest category, to research the present condition of evaluation practice, and to examine the improvement of science skill of 1st semester of 6-year of 24 public elementary school in seoul, was collected and analysed in a simple random sampling techniques. And also, 300 members of teachers who are charged with science skill, and school affairs responded to the questionnaire. The result of present research are following; 1. The content of criteria concluded category, unit, subject matter, aim, viewpoint, method, distributive score, scale and period in evaluation. 2. In the content of criberia of each school, Only 7 schools evaluated all the 4 units in text-book. When the teachers of science skill made the criteria, they made it super ficially with reference to previous materials. 3. The evaluation in the process of research showed that some behavior elements were essentially dealt with but others were never. The former was the capacity of dealing with experimental mechanism and material, the capacity of things and phenomena, the capacity of comparation and classification, communication and presentative capacity. The later was the establishment of theoretical model, the verification, capacity of analysis, cultivation experiment of plant and raising animal. 4. Every school had various difference from 40 point to 10 point in each unit score. Some schools didn't evaluate all the score that the Minister of education directed. But, most of schools showed that they were fulfilled the index through the evaluation of three stages. 5. 18 schools evaluated the attitude and interest, but most of schools evaluated only category of attitude evaluation moreover, the evaluation method of attitude varies with schools, like these : work-book testing or subject examination, announcement, learning attitude and science scrap-book. And also, two schools showed that they were evaluating cultivation experiment of plant and observational capacity. 6. Science skill was closely related to the fulfillment of researching process. But 66.8% represented the want of exercise evaluation. The causes are analysed as following ; first, Owing to dense members in a class, it was difficult to evaluate sufficiently and efficiently second, the method of the lesson was not researchful at last, the experimental instrument and facility were not enough. 7. The problems in the process of performance of the practical evaluation can be represented as a percentage so, 37.3% of object of investigation pointed out in sufficient support of evaluation implement which was utilized in the category of research process and evaluation of altitude and interest, 14.7% pointed out want of opportunity of teacher's training for performance of practical evaluation, also, the investigation showed that 49.2% of the teachers had never been instructed training about this. On the basis of above-mentioned discussion, I want to suggest follows; 1. The position of the criteria is as important as 80% of the whole. Therefore, for the purpose of evaluation evenly overall behavior element of science course, We must analyse theme in the classified units and select the evaluation element, extract the behavior element in each category for evaluative purpose and the survey and draw up dual object classified criteria. The evaluative plan, like this, must be established through a conference of the whole year. 2. Science skill has hierarchic system of spiral type. Therefore we must take the element of formative evaluation, because we can reflect the result (through evaluating, it, as soon as learning each units) in the progress of instruction-learning and survey whether the aim of each is success or failure for the purpose of the practice of this we must contain the evaluation period in the curriculum of educational process. 3. In the behavior element of each category, newly developed evaluation method and implement are supplied and utilized in the whole schools. For the purpose of this, the teachers must tie given train for the evaluation method and appliance separately. 4. In order to decrease the differences which were revealed in the establishment of the content of criteria, above all, we have to consider the basic research for this field and then, extract resonable or objective element of evaluative behavior, distributive score and stages. On the basis of it, the teachers must consult with this matter each other and consistently establish the practical evaluate criteria. 5. The behavior elements of the altitude and interest are not revealed in a moment but accomulatedly evaluated.;본 연구는 국민학교 자연과 교육목표가 지향하는 탐구과정영역과 태도·흥미영역의 목표도달 측정의 기준이 되는 실기평가 기준표를 분석하고 평가 시행 실태를 조사하여 그 개선의 방향을 알아보는데 목적이 있다. 이 목적을 수행하기 위하여 단순무선표집방법으로 서울시내 공립국민학교 6학년 1학기 자연과 실기평가 기준표를 24부 수집하여 내용을 분석하고, 표집대상 학교의 교무·연구·과학주임·6학년 주임교사와 6학년담임교사 300명을 대상으로 설문조사하였다. 본 연구에서 나타난 결과는 다음과 같다. 1. 실기평가 기준표에 포함되는 내용으로는 영역, 단원, 평가제제 평가목표 또는 문제. 평가방법 또는 요소, 평가방법, 배점, 척도, 평가시기 등이다. 2. 학교별 실기평가 기준표 내용에 있어서 교과서에 나오는 4가지 단원을 모두 평가하는 학교는 7개교이며 평가방법으로는 실험보고서, 관찰기록부, 학습장검사, 관찰 등의 방법을 쓰고 있다. 또한 기준표작성은 6학년 자연과 담당교사가 과거의 실기평가 기준표를 참고로 작성하는 것으로 나타나 있다. 3. 탐구과정영역 평가의 경우, 각 단원마다 가장 많은 비중을 차지하는 행동요소는 실험 및 재료를 다루는 능력, 사물과 현상의 관찰능력, 비교·분류하는 능력, 의사소통 및 제시 능력 등이고, 이론적 모형의 설정·검증 및 분석 능력, 식물 재배 및 동물 사육 능력 등에 대해서는 전혀 평가하지 않는 것으로 분석되었다. 4. 단원별 배점은 40점에서 10점까지 학교마다 차이가 있으며, 문교부가 제시한 평가 배정 80점을 모두 사용하여 않는 학교도 있다. 척도의 사용은 대부분의 학교가 3단계 평가를 실시하는 것으로 분석 되었다. 5. 태도·흥미영역 평가의 경우, 18개교가 평가를 하는 것으로 나타났고, 대부분의 학교가 태도영역만을 평가하며, 학습장·과제물검사, 발표력, 학습태도, 과학스크랩북 등 평가방법이 학교마다 차이가 있으며, 2개교는 탐구과정영역에 속하는 식물 재배 및 관찰 능력을 평가하는 것으로 분석되었다. 6. 자연과 실기평가는 탐구과정 이행과 밀접한 관계는 있으나, 탐구수행능력 체득에 있어서 66.8%는 실기평가가 미흡하다고 하였다. 그 이유로는 다인구 학급이라 적절한 평가실시가 어려우며, 수업이 탐구적인 방법으로 실시되지 않고, 평가가 필요한 실험도구·시설 등이 미비하다는 반응을 나타냈다. 7. 실기평가를 시행하는데 있어서 시정할 문제로는 37.3%가 탐구 과정영역, 태도·흥미영역의 평가에 필요한 평가도구의 보급을, 14.7%는 실기평가 시행에 대한 교사 연수의 기회를 지적하였고, 평가에 대한 연수를 받은 적이 없는 교사는 49.2%로 나타났다. 이상의 연구 결과를 종합하여 다음과 같은 제언을 하고자 한다. 1. 실기평가 기준표는 자연과 교육평가 전체의 80 %라는 높은비중을 차지하고 있다. 그러므로 자연과 교육목표가 추구하는 전반적인 행동요소를 고루 평가할 수 있도록 단원별로 학습과제를 분석하여 평가 제제를 선정하고, 평가목표와 목표측정을 위한 영역별 행동요소를 추출하여 이원 목적 분류표를 작성하며, 행동요소 평가에 알맞는 평가방법을 선택하는 등 사전의 평가계획이 학년 전체의 협의를 거쳐 수립되어야 하겠다. 2. 자연과 교과는 다른 교과와는 달리 나선형의 위계적 구조를 갖고 있다. 그러므로 단원 학습 후 즉시 평가를 하여 교수학습과정에 반영될 수 있도록, 형성평가적인 요소를 지녀야 하며, 이를 시행하기 위해서는 교육과정 진도에 있어서 각 단원마다 평가차시를 포함시켜야 하겠다. 3. 각 영역에 포함되는 행동요소에 대하여 개발된 평가방법과 도구는 일선학교에 보급되어 활용되어야 하며, 이를 위하여는 교사들에게 학교별·교육구청별로 평가방법과 도구의 사용법 등에 대한 연수가 실시되어야 하겠다. 4. 학교마다의 기준표 내용 설정에 대한 차이를 줄이기 위하여는 이러한 분야에 대한 기초연구가 이루어져 합리적이고 객관적인 평가행동요소, 배점, 단계 등을 추출하고, 자연과 주관 주임인 교무·연구·과학주임 교사가 서로 협의하여 지구별·교육구청별로 어느 정도 일관되고 객관성 있는 실기평가 기준표의 제시가 있어야 하겠다. 5. 태도·흥미영역의 행동요소들은 순간적으로 단기간내에 표출되는 것이 아니므로 이 영역의 평가를 위해서는 장기적인 안목에서 계획하여 누가적인 평가가 이루어져야 하겠다.목차 = ⅲ 논문개요 = ⅶ Ⅰ. 서론 = 1 A. 연구의 필요성 및 연구문제 = 1 B. 연구의 내용 = 5 C. 연구의 제한점 = 5 Ⅱ. 과학 교육 목표와 평가 방법 = 6 A. 지식·이해 영역 = 14 B. 탐구 과정 영역 = 17 C. 태도·흥미 영역 = 24 D. 선행 연구의 개관 = 28 Ⅲ. 연구의 방법 = 36 A. 대상 = 36 B. 도구 = 36 C. 자료 처리 방법 = 37 Ⅳ. 분석 및 결과 = 38 A. 자연과 실기평가 기준표 분석 = 38 B. 시행 실태 = 48 Ⅴ. 요약 및 결론 = 59 참고문헌 = 66 부록 = 70 ABSTRACT = 9

“Chemical-pain sensor” based on nanovesicle-carbon nanotube hybrid structures

We developed a "chemical-pain sensor" that could recognize chemical pain stimuli such as capsaicin and resiniferatoxin just like mammalian chemical pain sensory systems. Here, we first prepared nanovesicles containing rat pain sensory receptor, rat transient receptor potential vanilloid 1 (rTRPV1), which is activated by noxious heat and capsaicin. And the nanovesicles were immobilized on a single-walled carbon nanotube-based field effect transistor. The chemical-pain sensor could selectively detect chemical pain stimuli with a high sensitivity of a 1 pM detection limit. It also responded to different chemical pain stimuli in a manner similar as to that of mammalian chemical pain sensory systems. This sensor platform can be utilized for various practical applications such as food screening tools and artificial somesthetic sensors. Moreover, TRP families have been suggested as potential drug targets related to nerve and circulation disorders. Thus, the capability of monitoring TRP responses using our sensor platforms should provide a powerful means for the development of new drugs as well as the basic research about nerve and circulation systems.ope

Carmustine induces ERK- and JNK-dependent cell death of neuronally-differentiated PC12 cells via generation of reactive oxygen species

Accumulation of reactive oxygen species (ROS) caused by the inhibition of glutathione reductase (GR) has been proposed as one of the mechanisms responsible for carmustine (1,3-bis(2-chloroethyl)-1-nitrosourea, BCNU)-induced cytotoxicity. Since mitogen-activated protein kinases (MAPKs) are known to mediate ROS-dependent cell death in multiple cell types, we examined whether redox-sensitive MAPK activation mediated the carmustine-induced cell death of neuronally differentiated PC12 cells. Carmustine induced a concentration- and time-dependent cell death, which was associated with increased caspase-3 activation, a reduction in GR activity accompanied by a concomitant decrease in reduced glutathione levels, and accumulation of ROS. Carmustine-induced caspase-3 activation and cell death were prevented by pretreatment with anti-oxidants or a reducing agent, indicating that carmustine-induced caspase-3 activation and cell death occur via redox-dependent processes. Carmustine induced phosphorylation of the MAPKs, such as extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. The activation of these kinases was inhibited by pretreatment with N-acetyl-L-cysteine (NAC). Although all the MAPKs were activated by carmustine, only the inhibitors of JNK and ERK prevented carmustine-induced cell death and caspase-3 activation. Our data suggest that carmustine-induced neurotoxicity is, at least in part, due to the activation of ROS-dependent JNK and ERK signaling.ope

Neuroprotective effect of 3-morpholinosydnonimine against Zn2+-induced PC12 cell death

Excessive intracellular accumulation of zinc (Zn2+) is neurotoxic and contributes to a number of neuropathological conditions. Here, we investigated the protective effect of 3-morpholinosydnonimine (SIN-1) against Zn2+-induced neuronal cell death in differentiated PC12 cells. We found that Zn2+-induced PC12 cell death was reduced in a concentration-dependent manner by pretreatment with SIN-1. The intracellular accumulation of Zn2+ was not affected by pretreatment with SIN-1, indicating that SIN-1-induced neuroprotection was not attributable to reduced influx of Zn2+ into cells. SIN-1C, the stable decomposition product of SIN-1, failed to prevent Zn2+-induced cell death. Furthermore, the protective effect of SIN-1 against Zn2+-induced PC12 cell death was almost completely abolished by uric acid, a free radical scavenger, suggesting that reactive oxygen and nitrogen species generated by SIN-1 may contribute to the protective effect. SIN-1 prevented the inactivation of glutathione reductase (GR) and the increase in the ratio of oxidized glutathione/total glutathione (GSSG/total GSH) induced by Zn2+. Addition of membrane permeable GSH ethyl ester (GSH-EE) to PC12 cells prior to Zn2+ treatment significantly increased cell viability. We therefore conclude that SIN-1 may exert neuroprotective effect against Zn2+-induced cell death in differentiated PC12 cells by preventing inhibition of GR and increase in GSSG/total GSH ratio.ope

1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one induces cell cycle arrest and apoptosis in HeLa cells by preventing microtubule polymerization

1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) is known as a specific inhibitor of soluble guanylyl cyclase (sGC). Previously, however, ODQ was reported to induce cell death via sGC-dependent and sGC-independent means in a variety of cell types. The aim of this study was to investigate the mechanism by which ODQ induces cell death in HeLa cells. Treatment of HeLa cells with ODQ induced a concentration-dependent decrease in cell viability over the range from 10 to 100 μM. DNA fragmentation and fluorescence-activated cell sorting analysis using annexin V and propidium iodide staining revealed that ODQ triggered apoptosis at concentrations of 50 and 100 μM within 24 to 48 h. The addition of 8-Br-cGMP in the presence of ODQ failed to rescue HeLa cells from death, suggesting that the inhibition of sGC was not responsible for the pro-apoptotic action of ODQ. ODQ arrested the cell cycle at the G2/M phase and caused disassembly of the microtubule network. This process was reversed by dithiothreitol. In addition, ODQ was shown to inhibit the polymerization of purified tubulin, and this was also prevented by dithiothreitol. These results indicate that ODQ inhibits microtubule assembly by direct oxidation of tubulin, induces cell cycle arrest at the G2/M phase, and triggers apoptosis in HeLa cells.ope

Development of expression vector for brevibacterium helvolum

학위논문(석사) - 한국과학기술원 : 생물과학과, 2002.2, [ [v], [35] p. ]한국과학기술원 : 생물과학과

Comparison of Perioperative Complications between Reconstructive Pelvic Surgery and General Gynecologic Surgery

The purpose of this study was to compare the perioperative complication rates of reconstructive pelvic surgery and general gynecologic surgery, and to identify the predictive risk factors for perioperative complications in reconstructive pelvic surgery. The medical records of 148 reconstructive pelvic surgery patients and 146 general gynecologic surgery patients were reviewed, and the types of complications, along with their rates and predictive risk factors were examined. The statistical analysis included descriptive statistics and logistic regression. There was no difference in the type of complications between reconstructive pelvic surgery and general gynecologic surgery. The prevalences of perioperative complications were 34.4% in the reconstructive pelvic surgery group and 26.7% in the general gynecologic surgery group. Intraoperative blood loss (p=0.006) and the duration of surgery (p=0.014) were independent risk factors for perioperative complications in the reconstructive pelvic surgery group. The perioperative complication rates for the patients undergoing reconstructive pelvic surgery were not higher than those of the patients undergoing general gynecologic surgery, even though more procedures were performed and a longer duration of surgery was needed in the former cases. Since the duration of surgery and the amount of blood loss are the major factors affecting the complication rate, decreasing these two factors would be the key to improving the outcomes of patients undergoing reconstructive pelvic surgeryope