• 대한화학회지
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• 제36권1호
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• pp.100-106
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• 1992

스티렌-말레산(PSMA), 스티렌말레산 무수물(PSMAn), 및 스티렌-말레산의 $Eu^{3+}$ 염(PSMA-Eu)의 형광특성을 tetrahydrofuran 용액에서 연구하였다. 스티렌의 몰%가 75%인 PSMA와 PSMA-Eu은 들뜬 이합체의 결합에너지가 50%나 67%에 비해 크게 나타났다. 들뜬이합체-단위체 형광세기의 비로부터 스티렌 단위체의 농도가 $8.0{\times}10^{-3}M$까지도 분자내 들뜬이합체의 특성을 보였다. 들뜬이합체의 형성메카니즘을 설명하는 기존의 세 가지 모형은 이들 중합체에 대해서는 잘 맞지 않는 듯하다. benzylacetate, mesitylene 및 염소가 치환된 용매들이 들뜬이합체의 형광에 주는 영향을 을 조사하여 그 결과를 몰부피로 해석해 보았다.

• 멤브레인
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• 제9권1호
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• pp.10-16
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• 1999

본 연구에서는 pellet 상태의 polyetherimide (PEI)를 carbon tetrachloride(CCl4)와 1 ,2-dichloro-ethane (DCE) 의 부피비 5:1 하에서 PEI를 불균일한 상태로 유지시키고, chlorosulfonic acid (CSA)를 이용하여 PEI의 표면을 sulfonation 시킴으로써 , 음이온성을 띠며 친수성이 향상된 sulfonated polyetherimide (SPEI)를 제조하였다. 불균일한 상태가 유지되면서 가장 적합한 sulfonation 반응조건은 PEI: CSA 의 1 : 1 mole ratio, 온도 $10^{\circ}$, 3 시간이었다. 이온교환용량이 0.2~1.2meq/g을 갖는 SPEI를 합성할 수 있었고, FT-IR 측정을 통하여 sulfonic acid peak가 1020$cm^{-1}$ 와 1170$cm^{-1}$부근에서 관찰되었다. 분자량 분포는 sulfonation을 시킴으로써 좀 더 넓게 나타났고, 접촉각 측정을 통하여 친수성이 향상되었음을 확인하였다.

• 한국미생물·생명공학회지
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• 제19권3호
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• pp.308-312
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• 1991

B.thuringiensis subsp. darmstadiensis 73E10-2의 내독소에 대한 화학적 처리에서 고농도의 중성염(4M NaBr), 유기용매(50% acetone), 변성제(4M urea) 및 중성 계면활성제(10% triton X-100)로 내독소를 처리하였을 때 모기유충에 대한 독력의 소실이 거의 나타나지 않았으나, guanidine HCL이나 $CCl_4$ 또는 양이온 및 음이온 계면활성제로 처리함으로써 그 독력이 크게 소실되었다. 또한, 내독소의 sulfhydryl기의 변형은 모기유충에 대한 독력에 영향을 나타내지 못하였으나, lysine기 변형으로 내독소의 독력이 거의 완전히 소실되었다.

• 약학회지
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• 제31권6호
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• pp.361-369
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• 1987

The four azo dyes such as Amaranth (FD & C Red No. 2), Tartrazine (FD & C Yellow No. 4), sunset Yellow (FD & C Yellow No. 5) and Allura red (FD & C Red No. 40) are currently employed as a food additives in Korea. In this study, the effects of these azo dyes on the hepatic microsomal mixed function oxidase systems in Rats. (i.e., Cyt. P-450, Cyt. b$_5$, NADPH cyt. c-reductase and azo reductase) were investigated. Furthermore, to determine the relationship among the electron transport systems, each level of azo reductase, Cyt. P-450 and NADPH cyt. c-reductase was measured upon the administration of phenobarbital (known as an inducer of Cyt. P-450), 3-methylcholanthrene (Known as an inducer of Cyt. P-448), CoCl$_2$ (inhibitor on Cyt. P-450) or $CCl_4$ (inhibitor on Cyt. P-450). The results of these studies are as follows; (1) The levels of Cyt. P-450 and Cyt. b$_5$ were decreased upon the administration of these azo dyes. (2) When the level of Cyt. P-450 was decreased, the azo reductase activity was also decreased. (3) These azo dyes did not show any significant effect on the level of NADPH cyt. c-reductase. (4) The administration of 3-methylcholanthrene resulted in the elevation of azo reductase activity. The 3-methylcholanthrene may be responsible for the induction of CO-insensitive electron transport system.

• Archives of Pharmacal Research
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• 제27권6호
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• pp.600-603
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• 2004

(＋）-Dehydrovomifoliol (1）. 3-hydroxy-5$\alpha$,6$\alpha$-epoxy-$\beta$-ionone (2）, vitexin 7 -O-$\beta$-D-glucopyrano-side (3）, and vitexin 2'-O-$\beta$-D-glucopyranoside (4） were isolated as new constituents from the aerial parts of Beta vulgaris var. cicla. Compounds 3 and 4 demonstrated hepatoprotective activity with values of 65.8 and 56.1％, respectively, in primary cultured rat hepatocytes with $CCl_4$-induced cell toxicity, compared to controls. This was comparable to that of silibinin (69.8％） which was used as a positive control.trol.

• 대한화학회지
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• 제9권2호
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• pp.88-95
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• 1965

퓨란, 醋酸풀퍼릴, 풀퍼릴알코올과 마레인酸無水物을 에틸 에테르 存在下에서 附加反應시켜 exo附加物을 만들고 이 化合物들에 對한 臭素化反應을 물 存在下에서 行한 바 各各 모노부롬化락톤 및 디브롬酸을 生成하였으며 락톤의 生成收率은 轉位된 carbonium ion에 對한 carboxylic acid의 反應기여(participation)에 依하여 決定되면 化合物 自體의 立體條件(steric requirement)이 그 기여에 영향을 준다는 것을 究明하였다. 퓨란附加物을 有機溶媒(四鹽化炭素, 메틸렌크로라이드)存在下에서 臭素化反應하면 二臭化物이 生成하고 光線 存在下에서 鹽素化反應하면 四鹽化反應物이 生成됨을 究明하였다. 各 化合物의 合成方式 및 反應過程에 關하여 論及하였다.

• Carbon letters
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• 제7권4호
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• pp.259-265
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• 2006

Carbon-coated $TiO_2$ was prepared by $CCl_4$ solvent mixing method with the different heat treated temperatures (HTTs). Since the carbon layers derived from pitch on the $TiO_2$ particles were porous, the carbon-coated $TiO_2$ sample series showed a good adsorptivity. The values of BET surface areas measured were shown independently on the HTTs. The surface states by SEM present to the characterization of porous texture on the carbon-coated $TiO_2$ sample and carbon distributions on the surfaces. From XRD data, PT700 and PT750 were shown the X-ray diffraction patterns of the anatase $TiO_2$, but PT800 and PT850 were kept anatase-type structure even after heating at $800^{\circ}C$, though small amount of the rutile-type structure appears. The results of EDX microanalyses were observed for each sample show the spectra corresponding to almost all samples similar to C, O and Ti elements with an increase of HTTs. Finally, the excellent photoactivity of carbon-coated $TiO_2$ (especially, PT700 and PT750) could be attributed to the homogeneous coated carbon on the external surface and the structural anatase phase.

• 대한의생명과학회지
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• 제17권1호
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• pp.39-45
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• 2011

In the present study, we investigated whether volatile organic compounds induce inflammatory response in human T lymphocytes by evaluating the alteration of inflammatory cytokines. Volatile organic compounds such as formaldehyde, o-xylene, benzene, and hydroquinone have no cytotoxic effects on Jurkat T cells at a high concentration of 50 ${\mu}M$ for 48 h. IL-2, IL-4, IL-13, TNF-${\alpha}$ and IFN-${\gamma}$ were increased after the treatment with volatile organic compounds, although alteration of cytokines is different among volatile organic compounds. LPS as a positive control increased the secretion of IL-2, IL-4, IL-13, TNF-${\alpha}$ and IFN-${\gamma}$. MCP-1 and CCL17 (thymus and activation-regulated chemokine, TARC) were weakly increased after the treatment with volatile organic compounds but the amount of the increased cytokine was below 20 pg/ml. These results suggest that the measurement of cytokine in Jurkat T cells may be used as a useful method for evaluating the toxicity of volatile organic compounds in immune response.

• BMB Reports
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• 제51권4호
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• pp.182-187
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• 2018

In carcinoma, cancer-associated fibroblasts participate in force-mediated extracellular matrix (ECM) remodeling, consequently leading to invasion of cancer cells. Likewise, the ECM remodeling actively occurs in glioblastoma (GBM) and the consequent microenvironmental stiffness is strongly linked to migration behavior of GBM cells. However, in GBM the stromal cells responsible for force-mediated ECM remodeling remain unidentified. We show that tumor-associated mesenchymal stem-like cells (tMSLCs) provide a proinvasive matrix condition in GBM by force-mediated ECM remodeling. Importantly, CCL2-mediated Janus kinase 1 (JAK1) activation increased phosphorylation of myosin light chain 2 in tMSLCs and led to collagen assembly and actomyosin contractility. Collectively, our findings implicate tMSLCs as stromal cells providing force-mediated proinvasive ECM remodeling in the GBM microenvironment, and reminiscent of fibroblasts in carcinoma.

• 대한화학회지
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• 제40권6호
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• pp.415-419
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• 1996

수소결합, 유전효과 그리고 입체효과는 케톤의 카르보닐 신축진동을 결정하는 요인이 된다. 케톤의 카르보닐 신축진동은 다양한 용매에서 케톤의 농도변화에 영향을 받는다. 비극성용매에서 카르보닐 신축진동은 케톤의 부피%가 증가함에 따라 낮은 파수로 이동하고 극성용매에서는 높은 파수로 이동한다. 용매 아세토니트릴에서 카르보닐 신축진동은 dimethyl ketone을 제외하고 케톤의 부피%가 증가함에 따라 높은 파수로 이동한다. 용매의 극성이 증가할수록 카르보닐 신축진동은 낮은 파수로 이동하고 혼합용매 $CHCI_3CCI_4$에서 부피%가 증가할수록 낮은 파수로 이동한다.