• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E2
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• pp.121-128
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• 2002

This study was carried out to investigate if nitric oxide synthase (NOS) inhibitors modulate airway inflammation induced by diesel exhaust particles (DEP). N$\^$G/-nitro-L-arginine methyl ester (L-NAME), a potent constitutive NOS (cNOS) inhibitor, and aminoguanidine (AG), a selective inducible NOS (iNOS) inhibitor, were administered to mice in their drinking water for 7 weeks. Airway inflammation was elicited by the repeated intratracheal administration of DEP. The results showed that macrophages, inflammatory eosinophils and neutrophils in bronchoalveolar lavage (BAL) fluids by intratracheal DEP instillation were significantly suppressed in the mice treated with two NOS inhibitors toghther with DEP. The suppression of these cells was more effective in AG treated groups than in L -NAME treated groups. NOS inhibitor treatment also reduced interleukin -5 (IL-5 in the BAL fluids and lung homogenates. Additionally, it was found that eosinophil peroxidase (EPO) activity in the BAL fluids was also decreased by NOS inhibitor treatment. These results suggest that nitric oxide (NO) is produced in airway inflammation by repeated DEP instillation, and that iNOS inhibition as well as cNOS inhibition can play a modulating role in this airway inflammation by DEP.

• BMB Reports
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• v.39 no.6
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• pp.759-765
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• 2006

In this study, we investigate Nitric oxide synthase (NOS) expressions in adriamycin (ADR)-induced cadiomyopathy in rats. Sixty male Wistar rats were randomly divided into two main groups: control and ADR groups. Myocardial histopathological observation was performed; Expressions of 3 isoforms of NOS genes were examined by RT-PCR analysis; Expressions of 3 isoforms of NOS protein was assessed by Western blot analysis. Myocardium exhibited intensive morphological changes after 8 weeks of ADR treatment. The expression levels of inducible NOS (iNOS) gene and protein were significantly increased in ADR-treated rats after 8 weeks of treatment and then slightly increased at weeks 9 and 10. No significantly difference of neuronal NOS (nNOS) or endothelial NOS (eNOS) gene and protein were observed in the myocardium obtained from the control rats and ADR-injected rats at any time point. iNOS gene expression is selectively induced by ADR in heart. The upregulation of iNOS gene and protein may be somehow correlated with morphological changes seen in heart of rat treated with ADR.

• Journal of the Korean Chemical Society
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• v.66 no.2
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• pp.150-162
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• 2022

In this study, we investigated pre-service science teachers' NOS-PCK by analyzing their NOS lesson planning and demonstration. Four pre-service science teachers participated in the study. They planned and demonstrated NOS lessons in the context of 'Science Inquiry Experiment' developed under the 2015 Revised National Curriculum. Their lessons were observed. All of the teaching-learning materials were collected, and semi-structured interviews were also conducted. The analyses of the result revealed that pre-service teachers mainly referred to the curriculum and textbooks when selecting the NOS learning objectives. However, they felt difficulty because the curriculum and textbooks did not clearly present the NOS to be dealt. Although all of them took explicit approaches, there were not many open and divergent reflective approaches. In addition, they expected that high school students would consider scientific knowledge absolute and would have negative perceptions of NOS lessons. They rarely assessed students' NOS learning, and were reluctant to assess. Finally, most of them had a negative perception that learning NOS is not necessary for all students. On the bases of the results, educational implications for improving the expertise of pre-service science teachers in NOS lessons were discussed.

• Restorative Dentistry and Endodontics
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• v.24 no.1
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• pp.212-221
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• 1999

The periapical response to injury is a complex interaction of inflammatory, immune, neural, vascular and synthetic activity. Nitric oxide(NO), synthesized by nitric oxide synthetase(NOS) from L-arginine, is becoming recognized as an important bio-regulatory molecule in a variety of tissue, but little is known about its possible role in periapical tissue. The purpose of this study was to investigate the expression of nitric oxide synthetase(NOS) in tooth follicle, periapical abscess, granuloma and cyst. The expression of NOS in periapical lesions was evaluated by immunohistochemical staining for $NOS_2$, and $NOS_3$. The immunoreactivity was evaluated by staining intensity, and inflammatory cell infiltration. Correlationship between the periapical lesion in immunoreractivity were statistically analyzed by SPSS. The degree of $NOS_2$ and $NOS_3$ expression in periapical abscess was higher than in any other periapical lesions, and stastically significant. The expression degree of $NOS_2$ and $NOS_3$ was not correlated with periapical abscess and granuloma, but expression of $NOS_2$ showed very significant in periapical cyst. The increased expression of $NOS_2$ and $NOS_3$ was correlated with inflammatory cell infiltration degree of the periapical cyst. These results suggested that NO should play an important role in progress and/or mediation of periapical lesions.

• Molecules and Cells
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• v.19 no.3
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• pp.408-417
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• 2005

Nitric oxide (NO) occurs in various types of cells in the central nervous system. We studied the distribution and morphology of neuronal nitric oxide synthase (NOS)-containing neurons in the visual cortex of mouse and rabbit with antibody immunocytochemistry. We also compared this labeling to that of calbindin D28K, calretinin, and parvalbumin. Staining for NOS was seen both in the specific layers and in selective cell types. The densest concentration of intense anti-NOS immunoreactive (IR) neurons was found in layer VI, while the weak anti-NOS-IR neurons were found in layer II/III in both animals. The NOS-IR neurons varied in morphology. The large majority of NOS-IR neurons were round or oval cells with many dendrites coursing in all directions. Two-color immunofluorescence revealed that only 16.7% of the NOS-IR cells were double-labeled with calbindin D28K in the mouse visual cortex, while more than half (51.7%) of the NOS-IR cells were double-labeled with calretinin and 25.0% of the NOS-IR cells were double-labeled with parvalbumin in mouse. By contrast, 92.4% of the NOS-IR neurons expressed calbindin D28K while only 2.5% of the NOS-IR neurons expressed calretinin in the rabbit visual cortex. In contrast with the mouse, none of the NOS-IR cells in the rabbit visual cortex were double-labeled with parvalbumin. The results indicate that neurons in the visual cortex of both animals express NOS in specific layers and cell types, which do not correlate with the expression of calbindin D28K, calretinin or parvalbumin between the two animals.

• Advances in pediatric surgery
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• v.11 no.1
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• pp.9-18
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• 2005

Abnormal distribution of enteric nerves such as adrenergic, cholinergic and non-adrenergic non-cholinergic nerves (NANC) may cause the failure of relaxation at the involved bowel segment in Hirschsprung's disease (HD). Nitric oxide (NO) is a major inhibitory NANC neurotransmitter in the gastrointestinal tract. NO is synthesized by activation of nNOS (neuronal nitric oxide synthase) in the intramural ganglion cells and regulates bowel movement. To assess the distribution of nNOS in HD, immunohistochemical staining to nNOS was utilized on paraffin embedded specimens. Ten control colon specimens were tested for feasibility of staining. Immunohistochemisrty was done on ganglionic colon as well as aganglionic segment of 15 patients with HD. nNOS immunoreactivity was observed in the neuronal cells, small cells and nerve fibers in the muscle layer and submucosal neuronal cells of control specimens. This finding was also observed in the ganglionic segments of HD. But, there was no nNOS immunoreactivity in aganglionic segments of HD. In conclusion nNOS immunohistochemical staining of paraffin embedded specimen is feasible and reliable. And the results suggest that the relaxation failure of the aganglionic bowel in HD is related to the absence of nNOS containing cells and nerve fibers.

• Biomolecules & Therapeutics
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• v.10 no.4
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• pp.230-235
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• 2002

Gold sodium thiomalate (GST, gold compound) is a widely used anti-arthritic, anti-rheumatic and anti-inflammatory drug that is considered a good alternative to sodium salicylate (NaSA) for individuals who cannot tolerate salicylates. Nitric oxide (NO) synthesized by inducible nitric oxide synthase (iNOS) has been implicated as a mediator of inflammation. Recent evidence suggests that anti-inflammatory effect of NaSA lies in the inhibition of iNOS, but nothing has been reported about the direct effect of iNOS expression by GST. The present study was designed to elucidate sequentially the action mechanisms of GST and NaSA on lipopolysaccharide (LPS) plus interferon-gamma (IFN-$\gamma$) induced iNOS expression in RAW 264.7 macrophages. Both GST and NaSA inhibited NO production and iNOS protein expression in a dose dependent manner. GST inhibited iNOS mRNA expression induced by LPS plus IFN-$\gamma$, whereas NaSA did not. These findings suggest that GST may exert anti-arthritic, anti-rheumatic and anti-inflammatory effect by inhibiting iNOS expression induced by LPS plus IFN-$\gamma$ at transcriptional level, whereas NaSA exert its effect by inhibiting iNOS expression at the translational or posttranslational level.

• Journal of The Korean Association For Science Education
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• v.28 no.7
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• pp.749-758
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• 2008

Even though the importance of the nature of science (NOS) and scientific inquiry in science learning have been emphasized by many science educators and science curriculums, the link between the NOS and scientific inquiry has not been discussed sufficiently. In this article, I discussed that various aspects of NOS are already embedded in defining and characterizing the authentic scientific inquiry and that we need to have special concern about how the NOS should be treated and interpreted when introducing it into scientific inquiry. And I summarized two approaches to teach the NOS and scientific inquiry; teaching the NOS through scientific inquiry and teaching scientific inquiry through the NOS. Finally, some next studies based on this article are introduced.

• Journal of Korean Elementary Science Education
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• v.33 no.1
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• pp.44-56
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• 2014

이 연구의 목적은 인지적 전략인, 갈등도(Oh, 2011)를 기반으로 학생들이 명시적으로 과학의 본성(NOS)의 교육을 돕기 위하여 과학의 본성요소뿐만 아니라 과학의 역사를 담은 NOS Flow Map을 개발 제안하는 것이다. 예비적으로 과학의 본성의 교육을 위해 제안한 NOS Flow Map을 사용에 대한 이해를 탐색하기 위하여, 자신들의 NOS 이해를 강화하기 위해 우리가 제안한 NOS Flow Map의 유용성에 대한 예비 초등교사들의 인식를 조사하였다. 과학의 본성에 대한 중요한 관점들은 Kuhn의 과학철학과 역사가 아주 잘 일치된다. 즉 Kuhn의 과학혁명의 예로 가장 중요한 Copernicus의 혁명과정이 과학의 본성 중요한 요소들과 잘 일치됨을 보여준다. 따라서 이 연구에서 인지갈등을 통한 NOS 흐름도는 과학의 소양교육을 강화하는데 명시적이고 반성적인 도구이며 유망한 방법이라고 조심스럽게 제안한다.

• Journal of the Korean earth science society
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• v.24 no.2
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• pp.100-107
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• 2003

The purpose of this study is to assess gifted students' conceptions about nature of science (NOS). Scientifically gifted students who are expected to be professionals in the future should possess an adequate understanding of NOS that if firm foundation for scientific career. 47 volunteers from the 8th grade gifted science program in Seoul National University Gifted Education Center participated to answer questions inquiring NOS conceptions. Their answers were analyzed and compared to different groups such as non-gifted students and younger gifted students. As a result, gifted students' understanding of NOS appeared to surpass that of non-gifted students in many aspects and it seemed that gifted students formed their NOS view in early ages. The relative weakness in their NOS conceptions was found in understanding of scientific enterprise. Their strong misunderstanding about obstacles that minority people would face in scientific enterprise was noticed, too. They admitted that there has been discrimination in scientific enterprise, but they wrongly believed that outstanding scientists cannot be affected by it. Further studies will be required to probe more.