• Asian-Australasian Journal of Animal Sciences
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• v.22 no.9
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• pp.1320-1327
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• 2009

This study examined the effects of nicotinamide on proliferation, differentiation, and energy metabolism in a primary culture of bovine adipocytes. After treatment of cells with 100-500 $\mu{M}$ nicotinamide, cell growth was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and cellular lipid content was assessed by Oil Red O staining and a triglyceride (TG) assay. Several factors related to energy metabolism, namely adenosine triphosphatase (ATPase) activity, nitric oxide (NO) content, nitric oxide synthase (NOS) activity, the number of mitochondria and the relative expression of glyceraldehydes-3-phosphate dehydrogenase (GAPDH), peroxisome proliferator-activated receptor-$\gamma$ ($PPAR_{\gamma}$) and inducible NOS (iNOS), were also investigated. Results showed that nicotinamide induced both proliferation and differentiation in bovine preadipocytes. Nicotinamide decreased NO production by inhibiting NOS activity and iNOS mRNA expression, and controlled lipolytic activity by increasing ATPase activity and the number of mitochondria. The present study provides further evidence of the effects of nicotinamide on lipid and energy metabolism, and suggests that nicotinamide may play an important role in the development of bovine adipose tissue in vivo. This emphasizes the importance of investigating bovine adipose tissue to improve our understanding of dairy cow physiology.

• Culinary science and hospitality research
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• v.18 no.4
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• pp.233-242
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• 2012

Macrophage-derived nitric oxide (NO) plays an important role in immune responses. Overproduction of NO by inducible nitric synthase(iNOS) is known to be closely correlated with the pathology of a variety of diseases and inflammations. This study investigated the inhibitory effect of extract from various mushrooms(Phellinus linteus(PL), Inonotus obliquus(IO), Sarcodon aspratus(SA), Hericium erinacium(HE), and Russula cutefracta(RC)) on NO production and its molecular mechanism in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Among the mushrooms, HE extracts exhibited the strongest NO-inhibition activity. It was also found that HE extract inhibited LPS-induced iNOS and COX-2 expression in RAW264.7 cells. The present results give the understanding of biological activities of mushrooms and encourage their application for supplements and cook.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.420-433
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• 1996

Background : There have been many debates about the effects of nitric oxide on the neurogenic inflammation. The role of nitric oxide in the neurogenic inflammation of airways will be required a better understanding of the localization and types of nitirc oxide synthase(NOS) activity in the neurogenic inflammation of airways. Method : To investigate the role of nitric oxide in airway neurogenic inflammation, 1) the effects of neurokinin receptor antagonist (FK224) and nitric oxide synthase inhibitor, $N^{\omega}$-nitro-L-arginine (L-NNA) on plasma extravastion were evaluated in four groups of Sprague-Dawley rats ; sham operation group(sham NANC group), electrical vagal stimulation group(NANC2 group), intravenous pretreatment groups with FK224 (1mg/kg ; FK224 group), and L-NNA(1mg/kg ; L-NNA group) 15 minutes before vagal NANC stimulation. 2) NOS activity in trachea with neurogenic inflammation was localized by immunohistochemical stain. Immunohistochemical stain was performed by antibodies specific for inflammatory cells(iNOS), brain(bNOS), and endothelium (eNOS) on trachea obtained from sham NANC, NANC2, and FK224 groups. Results : The results are that plasma extravsation in neurogenic inflammation of rat airways was inhibited by FK224, but enhanced by L-NNA pretreatment(P<0.05). There was significantly increased infiltration of inflammatory cells in subepithelium of neurogenic inflammatory trachea, but the reduction of subepithelial infiltration of inflammatory cells was observed after pretreatment with FK224(P<0.05). Immunostaining with anti-iNOS antibody showed strong reactivity only in infiltrated inflammatory cells in neurogenic rat trachea, and these iNOS reactivity was reduced by pretreatment with FK224. bNOS immunoreactivity was significantly increased only in the nerves both of neurogenic inflammatory and FK224 pretreated trachea compared with sham NANC trachea(p<0.05). eNOS immunoreactivity was not significant change in endothelium in neurogenic inflammation of rat trachea. Conclusion : These results suggest that nitric oxide released from iNOS in infiltrated inflammatory cells has main role in neurogenic inflammation of rat trachea. The presence of bNOS immunoreactivity in the nerves indicates that nitric oxide may be released from the nerves in rat trachea with neurogenic inflammation.

• Journal of The Korean Association For Science Education
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• v.32 no.5
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• pp.823-840
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• 2012

The importance of teaching the nature of science (NOS) has been emphasized in the science curriculum, especially in the science curriculum for science-gifted students. Nevertheless, few studies concerning the structure and formation of students' mental model on NOS have been carried out. This study aimed to explore science-gifted students' understanding of 'fact', 'hypothesis', 'theory', 'law', and 'scientificness' by utilizing semantic network analysis. One hundred ten science-gifted middle school students who were selected by a national university participated in this study. We collected students' written responses of five items and analyzed them by the semantic network analysis(SNA) method. As a result, the core ideas of students' understanding of 'fact' were proof and reality, of 'hypothesis' were tentativeness and uncertainty, of 'theory' was proven hypothesis by experimentation, of 'law' were absoluteness and authority, and of 'scientificness' were factual evidence, verifiability, accurate and logical theoretical framework. The result of integrated semantic network illustrated that the viewpoint of science-gifted students were similar to absolutism and logical positivism (empiricism). Methodologically, this study showed that the semantic network analysis method was an useful tool for visualization of students' mental model of scientific conceptions including NOS.

• Journal of Korean Elementary Science Education
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• v.33 no.2
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• pp.207-216
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• 2014

Understanding the nature of science (NOS) has been a major component of scientific literacy and an important learning goal in science education (American Association for the Advancement of Science, 1990, 1993; Millar & Osborne, 1998; National Research Council, 1996, 2013). To achieve this goal, it is necessary to include appropriate views of the nature of science in science curriculum such as a textbook. The aim of this study was to conduct a content analysis of the elementary science textbooks to examine the presentation of the nature of science (NOS) using the four themes of scientific literacy, which are (1) nature of scientific knowledge, (2) nature of scientific inquiry, (3) nature of scientific thinking, and (4) nature of interactions among science, technology, and society (STS). Findings show while $3^{rd}$ and $4^{th}$ grade levels of science textbooks heavily emphasize on the Theme I, nature of scientific knowledge and the Theme II, the nature of scientific inquiry, the upper grade levels such as $5^{th}$ and $6^{th}$ grades of science textbooks are well balanced with the four themes of the nature of science. In addition, most of elementary science textbooks little focus on the Theme IV, nature of interactions among science, technology, and society (STS) among the four themes of the nature of science. It might be a shortcoming because the understanding the nature of interacions among science, technology and society (STS) is one of the key components in order for students to be a scientific literate person.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2153-2159
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• 2015

Mycoplasma hyopneumoniae is known to cause porcine enzootic pneumonia (EP), an important disease in swine production. The objective of this study was to examine the effects of sonicated protein fractions of M. hyopneumoniae on inflammatory response and gene expression in the murine alveolar macrophage MH-S cell line. The effects of sonicated protein fractions and intact M. hyopneumoniae on the gene expression of cytokines and iNOS were assessed using RT-PCR. The Annealing Control Primer (ACP)-based PCR method was used to screen differentially expressed genes. Increased transcription of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, COX-2, and iNOS mRNA was observed after exposure to the supernatant (SPT), precipitant (PPT), and intact M. hyopneumoniae protein. A time-dependent analysis of the mRNA expression revealed an upregulation after 4 h for IL-6 and iNOS and after 12 h for IL-1β and TNF-α, for both SPT and PPT; the fold change in COX-2 expression was less. A dose- and time-dependent correlation was observed in nitrite (NO) production for both protein fractions; however, there was no significant difference between the effects of the two protein fractions. In a differential gene analysis, PCR revealed differential expression for nine gene bands after 3 h of stimulation — only one gene was downregulated, while the remaining eight were upregulated. The results of this study provide insights that help improve our understanding of the mechanisms underlying the pathogenesis of and macrophage defenses against M. hyopneumoniae assault, and suggest targets for future studies on therapeutic interventions for M. hyopneumoniae infections.

• Culinary science and hospitality research
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• v.20 no.6
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• pp.190-199
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• 2014

This study was conducted to investigate the effects of the hot water extract from buckwheat (WEB) in RAW-264.7 macrophage cells against lipopolysaccharide (LPS). In these experiments, we evaluated the anti-inflammatory effects of WEB by measuring MTT assay, nitric oxide (NO), inducible NOS (iNOS) production, and cyclooxygenase-2 (COX-2) expression by Western blotting. The extracts showed a protective effect by increasing cell viability on LPS in RAW264.7 cells. WEB (0.25, 0.5, and 1.0 mg/mL) significantly suppressed LPS-stimulated production of NO. Also, WEB reduced the expression of iNOS and COX-2 proteins. The present results show that WEB has potent anti-inflammatory effects on RAW264.7 cells. In addition, WEB has various antioxidant effects as a result of 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) which possess a radical scavenging activity. The total polyphenol and flavonoid contents of the WEB were $13.22{\pm}3.69mg\;GAE/g$ extract and $38.53{\pm}5.20mg\;CE/g$ extract respectively. The present results give the understanding of biological activities of buckwheat and encourage their application for supplements.

• Journal of The Korean Association For Science Education
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• v.29 no.2
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• pp.221-239
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• 2009

The purpose of this study was to explore how 9th grade students' understanding of the nature of science developed during a one-year implementation of NOS learning materials. The lessons were a combination of short readings in episodes in the history of science with accompaning response booklets consisting of illustrations and questions. The lessons were designed to be 45 minutes in length and were implemented over ten months of the school term. Data on students' understanding as it developed during the implementation were obtained from test items, questionnaires, and students' journal. Findings indicate that students showed changes in their understanding of the nature of science towards modern views of the nature of science. However, they showed understanding of tentativeness of scientific knowledge, they also showed belief of absoluteness of scientific knowledge.

• Journal of The Korean Association For Science Education
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• v.34 no.5
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• pp.459-468
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• 2014

Educational Discourses on the nature of science(NOS) identify understanding of the role of scientific knowledge, especially the distinction between law and theory, as a crucial goal of instruction. However, the scientist community uses the terms such as law, theory, and principle without explicit definition so that the terms have no coherent meanings in their conventional language expression. The inconsistency between the norm and the reality could impose confusion on the teaching and learning. From the awareness of the problem, this study critically reviews the science education research papers and literatures on the philosophy of science which focus on the meaning of law, theory, or principle and the structure of scientific knowledge. From the examination of the science education researches, it is revealed that the disparity between the normative meanings of the law and theory by NOS researchers and actual usage of the terms is quite serious. From the review of the literatures of the philosophy of science, the necessity of the distintion of three categories: law, theory, and principle beyond the dichotomy between law and theory is brought up. By synthesizing the related literatures, we provide an outline of the characteristics of knowledges belonging to law, theory, and principle. Considering the conflict between the normative definition and the conventional language, it could be unnecessary to emphasize clear distinction on the terms as an instructional goal. Instead, the goal of instruction should focus on that there are three types of scientific knowledges of different functions and characteristics.

• Journal of The Korean Association For Science Education
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• v.31 no.4
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• pp.539-556
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• 2011

The purpose of this study was to examine preservice secondary science teachers' understanding of the nature of science, by using nature of science (NOS) questionnaire on the basis of atomic model, and compare this to pre-studies. 'Understanding of nature of scientific model,' 'Tentativeness of scientific knowledge,' 'Subjectivity in science,' 'Use of inference and imagination,' 'Myths of the scientific method,' and 'Comparison between science and art.' were examined. Preservice teachers showed great comprehension of the tentativeness of scientific knowledge (the orbital model) and the subjectivity in science (the different interpretation about the experiment of particle scattering), but displayed the lowest comprehension of the scientific method. For understanding of nature of scientific model (the atomic model) and the comparison between science (Bohr's atomic model) and art (Picasso's work), preservice teachers brought out a combination of ontological and constructivist perspective and showed the contradictory thought about imagination in science research. In the result of comparison to pre-studies using the NOS instruments contains general terms, represented high levels of agreement about the tentativeness of scientific knowledge by using concrete examples of 'atomic model'. When concrete scientists such as Thomson, Rutherford, Bohr were presented, respondents revealed more informed views about the scientists' research method.