• 한국과학교육학회지
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• 제28권1호
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• pp.89-99
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• 2008

이 연구에서는 과학사 소재를 활용한 명시적 반성적 과학의 본성(NOS) 수업이 학생들의 과학의 본성에 대한 이해, 학업 성취도, 과학 수업에 대한 즐거움에 미치는 효과를 조사하였다. 남녀 공학 중학교 3학년 4학급(129명)을 통제 집단과 처치 집단으로 배치하였다. '물질의 구성' 단원에 대하여 11차시 동안 수업을 실시하였다. 수업 처치 전, 두 집단의 학생들은 대부분 과학의 본성에 대해 부적절한 견해를 지니고 있었다. 수업 처치 후, 통제 집단 학생들의 과학의 본성에 대한 견해는 변하지 않았으나, 처치 집단의 학생들은 과학의 본성에 대해 보다 적절한 이해를 나타내었다. 처치 집단의 상위 학생들은 하위 학생들보다 과학의 본성에 대해 보다 적절한 관점을 지니게 되었다. 그러나 학업성취도와 과학 수업에 대한 즐거움 검사에서는 두 집단 간 점수 차이가 통계적으로 유의미하지 않았다.

• Journal of Chest Surgery
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• 제49권6호
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• pp.443-450
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• 2016

Background: Although unique aortic pathology related to bicuspid aortic valve (BAV) has been previously reported, clinical implications of BAV to aortopathy risk have yet to be investigated. We looked for potential differences in matrix protein expressions in the aortic wall in BAV patients. Methods: Aorta specimens were obtained from 31 patients: BAV group (n=27), tricuspid aortic valve (TAV) group (n=4). The BAV group was categorized into three subgroups: left coronary sinus-right coronary sinus (R+L group; n=13, 42%), right coronary sinus-non-coronary sinus (R+N group; n=8, 26%), and anteroposterior (AP group; n=6, 19%). We analyzed the expression of endothelial nitric oxide synthase (eNOS), matrix metalloproteinase (MMP)-9, and tissue inhibitor of matrix metalloproteinase (TIMP)-2. Results: Based on the mean value of the control group, BAV group showed decreased expression of eNOS in 72.7% of patients, increased MMP-9 in 82.3%, and decreased TIMP in 79.2%. There was a higher tendency for aortopathy in the BAV group: eNOS $(BAV:TAV)=53%{\pm}7%:57%{\pm}11%$, MMP-9 $(BAV:TAV)=48%{\pm}10%:38%{\pm}1%$. The AP group showed lower expression of eNOS than the fusion (R+L, R+N) group did; $48%{\pm}5%$ vs. $55%{\pm}7%$ (p=0.081). Conclusion: Not all patients with BAV had expression of aortopathy; however, for patients who had a suspicious form of bicuspid valve, aortic wall biopsy could be valuable to signify the presence of aortopathy.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권4호
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• pp.277-286
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• 2006

In the present study, I investigated the effects of N-methyl-D-aspartate (NMDA), arachidonic acid (AA), and Nitric Oxide Synthase Inhibitor (NOS-I), alone or in combination, on the viability of cultured primary normal human oral keratinocytes (NHOK). Specifically, we examined whether AA and NOS-I could protect primary NHOK from glutamate cytotoxicity. The purpose of this study was therefore the preliminary study for the examination of the interaction between these agents and NHOK in order to elucidate the mechanisms by which epithelial growth and regeneration are regulated. NHOK were obtained from gingival tissue of 20 individuals aged 20 to 29, and third passage (P3) cells were used for this study. Cell viability was measured by the MTT assay. NMDA and NNA, a calcium dependent NOS inhibitor, induced an initial increase in cell number, which subsequently decreased by the $7^{th}$ day. Low concentration of AA ($0.5\;{\mu}M$ & $1\;{\mu}M$) induced an increase in cell number while high concentrations of AA ($5\;{\mu}M$ & $10\;{\mu}M$) induced a decrease in cell number. The decrease in cell number induced by NMDA at the $7^{th}$ day was abolished by the addition of low concentrations of AA ($0.5\;{\mu}M$ & $1\;{\mu}M$) or NOS inhibitors. Low concentrations of AA ($0.5\;{\mu}M$ & $1\;{\mu}M$) or NOS inhibitors may protect the NHOK from NMDA induced cytotoxicity. These reactions might be related to the NMDA receptor in the cell and the change of the intracellular calcium ion concentration.

• Neonatal Medicine
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• 제18권1호
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• pp.59-69
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• 2011

목적: 6-cyano-7-nitroquinoxalin-2,3-dione (CNQX)는 저산소성허혈성뇌병증, 외상성뇌손상, 흥분독성과 같은 뇌 손상동물 모델에서 보호 효과가 있다고 발표되고 있지만 신생아기에 그 효과에 대해서는 아직 제한적이다. 저자들은 CNQX를 이용하여 저산소성허혈성뇌손상을 동반한 발달 과정에 있는 흰쥐 뇌에 산화질소합성효소 중재를 통한 뇌 보호 효과를 알아보고자 하였다. 방법: 생체내 실험으로 생후 7일된 신생 흰쥐의 좌측 총 경동맥을 결찰한 후 6개군(정상산소군, 수술없이 저산소군, sham수술 후 저산소군, 수술 후 저산소군, vehicle 투여 후 저산소군, CNQX 투여 후 저산소군)으로 나누었고, 저산소 손상은 특별히 제작한 통속에서 2시간 동안 8% $O_2$에 노출시켰다. CNQX은 뇌손상 전 30분에 체중 kg당 10 mg를 투여하였다. 생체외 실험으로 재태기간 18일된 태아 백서의 대뇌피질 세포를 배양하여 정상산소군은 5% $CO_2$ 배양기(95% air, 5% $CO_2$)에 두었고, 저산소군과 뇌손상 전 CNQX 투여군(10 ${\mu}g$/mL)은 1% $O_2$). 배양기(94% $N_2$, 5% $CO_2$)에서 16시간동안 뇌세포손상을 유도하였다. 생체내 외 실험 모두 산화질소합성효소와 관련된 iNOS, eNOS, nNOS 항체와 primer를 이용하여 western blotting과 실시간중합효소연쇄반응을 시행하였다. 결과: 산화질소합성효소와 관련된 생체외 내 실험에서 iNOS와 eNOS의 발현은 저산소군에서 정상산소군보다 감소하였으나 CNQX 투여군에서는 저산소군보다 증가하였다. nNOS의 발현은 반대로 표현되었다. 결론: 본 연구에서 CNQX는 산화질소합성효소 중재를 통하여 주산기 저산소성 허혈성 뇌손상에서 신경보호 역할을 하는 것을 알 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2929-2937
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• 2015

Endothelial nitric oxide synthase (eNOS or NOS3) produces nitric oxide and genetic polymorphisms of NOS3 gene play significant roles in various processes of carcinogenesis. The results from published studies on the association between NOS3 G894T and NOS3 intron 4 (4a/b) polymorphisms and cancer risk are conflicting and inconclusive. However, i n order to assess this relationship more precisely, a meta-analysis was performed with PubMed (Medline), EMBASE and Google web searches until February 2014 to select all published case-control and cohort studies. Genotype distribution data were collected to calculate the pooled odd ratios (ORs) and 95% confidence intervals (CIs) to evaluate the strength of association. A total of 10,546 cancer cases and 10,550 controls were included from twenty four case-control studies for the NOS3 G894T polymorphism. The results indicated no significant association with cancer risk as observed in allelic (T vs G: OR=1.024, 95%CI=0.954 to 1.099, p=0.508), homozygous (TT vs GG: OR=1.137, 95%CI=0.944 to 1.370, p=0.176), heterozygous (GT vs GG: OR=0.993, 95%CI=0.932 to 1.059, p=0.835), recessive (TT vs GG+GT: OR=1.100, 95%CI=0.936 to 1.293, p=0.249) and dominant (TT+GT vs GG: OR=1.012, 95%CI=0.927 to 1.105, p=0.789) genetic models. Similarly, a total of 3,449 cancer cases and 3,691 controls were recruited from fourteen case-control studies for NOS3 4a/b polymorphism. Pooled results indicated no significant association under allelic (A vs B: OR=0.981, 95%CI=0.725 to 1.329, p=0.902), homozygous (AA vs BB: OR=1.166, 95%CI=0.524 to 2.593, p=0.707), heterozygous (BA vs BB: OR=1.129, 95%CI=0.896 to 1.422, p=0.305), dominant (AA+BA vs BB: OR=1.046, 95%CI=0.779 to 1.405, p=0.763) and recessive (AA vs BB+BA: OR=1.196, 95%CI=0.587 to 2.439, p=0.622) genetic contrast models. This meta-analysis suggests that G894T and 4a/b polymorphisms of NOS3 gene are not associated with increased or decreased risk of overall cancer.

• Biomolecules & Therapeutics
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• 제22권6호
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• pp.510-518
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• 2014

Chronic (>24 h) exposure of arsenite, an environmental toxicant, has shown the decreased nitric oxide (NO) production in endothelial cells (EC) by decreasing endothelial NO synthase (eNOS) expression and/or its phosphorylation at serine 1179 ($eNOS-Ser^{1179}$ in bovine sequence), which is associated with increased risk of vascular diseases. Here, we investigated the acute (<24 h) effect of arsenite on NO production using bovine aortic EC (BAEC). Arsenite acutely increased the phosphorylation of $eNOS-Thr^{497}$, but not of $eNOS-Ser^{116}$ or $eNOS-Ser^{1179}$, which was accompanied by decreased NO production. The level of eNOS expression was unaltered under this condition. Treatment with arsenite also induced reactive oxygen species (ROS) production, and pretreatment with a ROS scavenger N-acetyl-L-cysteine (NAC) completely reversed the observed effect of arsenite on $eNOS-Thr^{497}$ phosphorylation. Although protein kinase C (PKC) and protein phosphatase 1 (PP1) were reported to be involved in $eNOS-Thr^{497}$ phosphorylation, treatment with PKC inhibitor, Ro318425, and overexpression of various PKC isoforms did not affect the arsenite-stimulated $eNOS-Thr^{497}$ phosphorylation. In contrast, treatment with PP1 inhibitor, calyculin A, mimicked the observed effect of arsenite on $eNOS-Thr^{497}$ phosphorylation. Lastly, we found decreased cellular PP1 activity in arsenite-treated cells, which was reversed by NAC. Overall, our study demonstrates firstly that arsenite acutely decreases NO production at least in part by increasing $eNOS-Thr^{497}$ phosphorylation via ROS-PP1 signaling pathway, which provide the molecular mechanism underlying arsenite-induced increase in vascular disease.

• Archives of Pharmacal Research
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• 제20권3호
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• pp.239-246
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• 1997

In the present study, liver regeneration rate (%) was increased up to 70% 3 days after partial hepatectomy (PH). Nitric oxide synthase (NOS) activity in liver tissue as well as serum nitrite/ nitrate content had no timed response, revealing no significant difference between shamoperated and partially hepatectomized rat liver. Contents of free methylarginines in liver tissue were increased biphasically in a time-dependent manner after PH. However, those in serum did not exhibit the same patterns as in liver. Taken together, the results suggest that $N^{G}$-monomethyl-L-arginine (MMA) and $ N^{G}, N^{G}$-dimethylarginine (DMA) play a role in inhibiting nitric oxide (NO) synthesis in regenerating rat liver because the increase of their contents was synchronized with NOS expression.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Molecular and Cellular Response to Toxic Substances
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• pp.188-189
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• 2002

This work aimed to identify neuronal cell toxicity induced by decrease of physiological NO production by differential phosphorylation of constitutive neuronal NO synthase (nNOS), which can be mediated by Ca2+-dependent PKC and/or CaM-KII activities activated by metals.(omitted)

• 대한간호학회지
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• 제41권4호
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• pp.520-527
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• 2011

Purpose: The purpose of this study was to examine effects of nitric oxide synthase (NOS) inhibitor on muscle weight and myofibrillar protein content of affected and unaffected hindlimb muscles in rats with neuropathic pain induced by unilateral peripheral nerve injury. Methods: Neuropathic pain was induced by ligation and cutting of the left L5 spinal nerve. Adult male Sprague-Dawley rats were randomly assigned to one of two groups: The NOSI group (n=19) had NOS inhibitor (L-NAME) injections daily for 14 days, and the Vehicle group (n=20) had vehicle injections daily for 14 days. Withdrawal threshold, body weight, food intake and activity were measured every day. At 15 days all rats were anesthetized and soleus, plantaris and gastrocnemius muscles were dissected from hindlimbs. Muscle weight and myofibrillar protein content of the dissected muscles were determined. Results: The NOSI group showed significant increases as compared to the Vehicle group for body weight at 15 days, muscle weight and myofibrillar protein content of the unaffected soleus and gastrocnemius. The NOSI group demonstrated a higher pain threshold than the vehicle group. Conclusion: NOSI for 14 days attenuates unaffected soleus and gastrocnemius muscle atrophy in neuropathic pain model.

• 생명과학회지
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• 제21권12호
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• pp.1689-1697
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• 2011

본 연구는 고마리 추출물이 가지는 항염증 활성을 알아보기 위하여 쥐의 대식세포(RAW264.7 cell)에 Lipopolysaccharide (LPS)를 처리하여 염증반응을 유도하고 이때 발생되는 Nitric oxide (NO)의 생성 억제를 확인하였다. 또한 염증에서 중요하게 알려져 있는 Inducible nitric oxide synthase (iNOS), Cyclooxygenase-2 (COX-2), Nuclear factor-kappa B (NF-${\kappa}B$) 단백질들의 발현을 비교하였고, 추가적으로 NF-${\kappa}B$ 단백질의 핵 내부로의 이전 및 활성을 확인하였다. 메탄올 추출물은 NO 생성 및 iNOS, COX-2, NF-${\kappa}B$ 단백질의 발현을 억제하고, 세포를 보호하는 효과를 가지는 Heme oxygenase-1 (HO-1) 단백질의 발현을 증가시켰다. 위 결과를 바탕으로 하여 n-butanol, hexane, ethyl acetate 용매를 이용한 추가적인 분획을 실시하였다. 이들 분획 중 고마리의 ethyl acetate 추출물은 Prostaglandin $E_2$ ($PGE_2$), NO 생성을 억제 하였으며, iNOS, COX-2 단백질들의 발현을 감소, NF-${\kappa}B$의 핵 내부로의 이동을 억제하는 효과가 높다는 것을 확인하였다. 이러한 연구결과는 고마리 식물이 좋은 항염증 활성을 가지고 있음을 나타내며, 지속적인 분획으로 고마리 식물이 가지는 항염증 활성 물질을 선별하여 그 작용기작을 규명하는 연구가 필요하다.