• BMB Reports
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• 제39권2호
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• pp.150-157
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• 2006

Native grass carp (Ctenopharygodon idellus) growth hormone, has 5 cysteine amino acid residues, forms two disulphide bridges in its mature form. Recombinant grass carp growth hormone, when over-expressed in E. coli, forms inclusion bodies. In vitro oxidative renaturation of guanidine-hydrochloride dissolved recombinant grass carp growth hormone was achieved by sequential dilution and stepwise dialysis at pH 8.5. The redox potential of the refolding cocktail was maintained by glutathione disulphide/glutathione couple. The oxidative refolded protein is heterogeneous, and contains multimers, oligomers and monomers. The presence of non-disulphide-bond-forming cysteine in recombinant grass carp growth hormone enhances intermolecular disulphide bond formation and also non-native intramolecular disulphide bond formation during protein folding. The non-disulphide-bond-forming cysteine was converted to serine by PCR-mediated site-directed mutagenesis. The resulting 4-cysteine grass carp growth hormone has improved in vitro oxidative refolding properties when studied by gel filtration and reverse phase chromatography. The refolded 4-cysteine form has less hydrophobic aggregate and has only one monomeric isoform. Both refolded 4-cysteine and 5-cystiene forms are active in radioreceptor binding assay.

• BMB Reports
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• 제44권11호
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• pp.747-752
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• 2011

To investigate the effects of disulphide bond position on the salt resistance and lipopolysaccharide (LPS)-neutralizing activity of ${\alpha}$-helical homo-dimeric antimicrobial peptides (AMPs), we synthesized an ${\alpha}$-helical model peptide ($K_6L_4W_1$) and its homo-dimeric peptides (di-$K_6L_4W_1$-N, di-$K_6L_4W_1$-M, and di-$K_6L_4W_1$-C) with a disulphide bond at the N-terminus, the central position, and the C-terminus of the molecules, respectively. Unlike $K_6L_4W_1$ and di-$K_6L_4W_1$-M, the antimicrobial activity of di-$K_6L_4W_1$-N and di-$K_6L_4W_1$-C was unaffected by 150 mM NaCl. Both di-$K_6L_4W_1$-N and di-$K_6L_4W_1$-C caused much greater inhibitory effects on nitric oxide (NO) release in LPS-induced mouse macrophage RAW 264.7 cells, compared to di-$K_6L_4W_1$-M. Taken together, our results indicate that the presence of a disulphide bond at the N- or C-terminus of the molecule, rather than at the central position, is more effective when designing salt-resistant ${\alpha}$-helical homo-dimeric AMPs with potent antimicrobial and LPS-neutralizing activities.

• 한국식품과학회지
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• 제22권1호
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• pp.44-49
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• 1990

열풍건조법과 동결건조법으로 제조한 분말마늘의 품질을 비교 조사하였다. 마늘의 휘발성 향기성분을 분리하는데 porapak Q 칼럼이 비교적 적합하였으며 FD-3구를 제외한 모든 동결건조구에서 열풍건조구에 비하여 diallyl disulphide, $P_t$, alliin의 함량이 높게 나타났다. 색차계로 분말마늘의 색도를 조사한 결과. 열풍건조구가 동결건조구에 비하여 갈변현상이 심하게 나타났으며 주사전자현미경으로 분말마늘의 미세조직을 관찰한 결과 동결건조 분말은 상당히 다공성이었다.

• 대한화학회지
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• 제55권2호
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• pp.218-229
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• 2011

Imine 화합물 1을 hydrazine hydrate와 같은 nitrogenous 시약과 반응시켜서 치환된 pyrimidines 화합물을 합성하였다. 얻어진 화합물 2를 다양한 반응조건, 즉 propionic acid, formic acid, ethyl chloroformate, acdetic anhydride, carbon disulphide, cyanogene bromide, triflauroacetic acid 및 ethyl chloroacetate와 반응시켜서 대응하는 화합물을 좋은 수율로 얻었으며, 반응은 Dimroth-type 자리옮김 반응을 통하여 진행되었다.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2009년도 학술발표대회
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• pp.69-70
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• 2009

• Archives of Pharmacal Research
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• 제21권6호
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• pp.723-728
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• 1998

The chemical behaviours of 4-methyl-2-oxo-2H-benzopyran-7-yl oxoacetyl hydrazine (2) towards some different reagents such as anhydride compounds, aromatic aldehydes, carb on disulphide, and nitrous acid yielded the corresponding pathalazine derivatives (3, 4, 5), hydrazone derivative (6), 1,3,4-oxadiazole derivative (7, 8, 9) and acid azide (10) respectively. Treatmen of 10 with absolute alcohols, amines and ethyl amino acid ester gave the corresponding carbamate derivative (11), substituted urea derivative (12) and ethyl substituted alkyl acetate (13) respectively. The biological activity of some synthesized compounds was evaluated.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.41-47
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• 2002

The reactions of 3-methyl-1-phenyl-5-oxo-${\Delta}^2$-pyrazoline-4-thiocarbohydrazide towards phenyl isothiocyanate, sodium nitrite, cyclohexanone, aromatic aldehydes, and carbon disulphide has been studied. The Vilsmeier-Haack reaction has been applied on 4-substituted pyrazolone derivatives.

• Tribology and Lubricants
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• 제5권2호
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• pp.87-93
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• 1989

The effect of the Concentration of solid lubricant, MoS$_2$ alone and in presence of other additives, ZDDP and DEP on the wear characteristics of liquid lubricants has been studied using the Four Ball Wear tester and Falex E.P. tester. On the basis of the experimental result, it showed that the concentration of MoS$_2$ and compatibility with other additives is very cbncerned with wear performance.

• Safety and Health at Work
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• 제11권2호
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• pp.215-221
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• 2020

Background: The aim of this study is to illustrate the historical role of the International Commission on Occupational Health (ICOH) congresses as an arena where national and international occupational medicine can dialogue and as the first example of scientific transferability of the research and prevention results that have had such an impact on global public health. Methods: We used the ICOH Heritage Repository, in which ICOH congress proceedings (from the first congress in Milan in 1906 to the last congress, held in Dublin in 2018), are organised in an orderly way, updated and easily accessible according to open access logic. Results: We describe studies by three physicians who submitted significant scientific work to ICOH congresses, one on the battle against ancylostomiasis (Volante, 1906), the second (Quarelli, 1928) on carbon disulphide poisoning, and the third (Viola, 1969) on the carcinogenicity of vinyl chloride monomer. Priority is given to Italian cases, on account of the authors' obvious familiarity with the issues. Conclusion: The visibility offered in ICOH conferences and their published proceedings has boosted the international spread of their findings, contributing to the scientific transferability of the research results and influencing the development of policies and prevention interventions that have had a great impact on global public health.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.287.1-287.1
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• 2013

The Isolation of few-layered transition metal dichalcogenides has mainly been performed by mechanical and chemical exfoliation with very low yields. in particular, the two-dimensional layer of molybdenum disulfide (MoS2) has recently attracted much interest due to its direct-gap property and potential application in optoelectronics and energy harvesting. However, the synthetic approach to obtain high-quality and large-area MoS2 atomic thin layers is still rare. In this account, a controlled thermal reductionsulfurization method is used to synthesize large-MoOx thin films are first deposited on Si/SiO2 substrates, which are then sulfurized (under vacuum) at high temperatures. Samples with different thicknesses have been analyzed by Raman spectroscopy and TEM, and their photoluminescence properties have been evaluated. We demonstrated the presence of single-, bi-, and few-layered MoS2 on as-grown samples. It is well known that the electronic structure of these materials is very sensitive to the number of layer, ranging from indirect band gap semiconductor in the bulk phase to direct band gap semiconductor in monolayers. This synthetic approach is simple, scalable, and applicable to other transition metal dichalcogenides. Meanwhile, the obtained MoS2 films are transferable to arbitrary substrates, providing great opportunities to make layered composites by stacking various atomically thin layers.