• Journal of Environmental Health Sciences
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• v.28 no.2
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• pp.71-80
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• 2002

To evaluate the skin toxicity of topical cyclohexane application (25mg/$\textrm{cm}^2$) was sequentially applied to the rat skin for four days. On the histopathological findings in the light micrographs, neutrophils and engulfed neutrophils are seen, and many cytoplasmic processes were appeared in proliferated layer whereas in the dermis area, increased numbers of fibroblast, accumulation of neutrophil and lipid droplets are demonstrated. On the other hand, applying the cyclohexane to the rat skin led to the remarkable rise of cutaneous xanthine oxidase activity and similar activities of superoxide dismutase and glutathione peroxidase and glutathione content and declined activity of glutathione S-transferase compared with control group. Especially the remarkably decreased activity of aniline hydroxylase (AH) was appeared in skin as little as scarcely determined. Furthermore, the applying the cyclohexane to skin led to the significantly increased activity of hepatic AH and alcohol dehydrogenase. These results indicate that oxygen free radical and intermediate metabolite of cyclohexane may be responsible for structural changes in skin by cyclohexane application to rat skin.

• Journal of Life Science
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• v.8 no.4
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• pp.395-399
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• 1998

Neurokinin A(NKA) and its derivatives ([Nle$^{7}$NKA,[Leu$^{7}$NKA] were synthesized by solid phase peptide synthesis method using Fmoc-TFA strategy and their smooth muscle contractile activities were measured to examine the structural effect of alkyl group at the 7th amino acid NKA on the smooth muscle contractile activity. The smooth muscle contractile activity. The smooth muscle contractile activities of [Nle$^{7}$]NKA and [Leu$^{7}$]NKA were only 5.64% and 1.55%, respectively when compared with NKA. This result suggested that the more three dimensional structure of th 7th amino acid as well as the whole message segment of NKA would be necessary to show the biological activity.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2003.11a
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• pp.46-46
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• 2003

Hypocholesterolemic peptide isolated from glycimin (11S protein) hydrolyzate by trypsin was purified and identified as LPYP and IAVPGEVA. To investigate the effects of phyiscal properties of side chains of the hypocholesterolemic activity, some of mutant peptides were designed and synthesized chemically. The structure related structures of each peptide were simulated and constructed and their conformations were observed by using spectropolarimeter. The hypocholesterolemic activities were monitored by assaying the inhibition of 3-hydroxy-3-methylglutaryl CoA reductase (HMG-CoA reductase) in vitro and by the determination of cholesterol content in mice serum. For LPYP derivatives, Hypocholesterolemic activity was lost when hydrophobic leucine residue at N-terminus was not so critical for maintaining hypocholesterolemic activity. For idealogical design of hypocholesterolemic peptides, the structure of HMG-CoA reductase are shown and inhibition mechanism of some peptides or inhibitors will be presented. For IAVPGEVA derivative inhibition of HMG-CoA reductase has been studied. For detail study of hypocholesterolemic activity, kinetic study of inhibition of peptides on HMG-CoA reductase and structural view of ligand binding should be investigated.

• Archives of Pharmacal Research
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• v.13 no.4
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• pp.385-387
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• 1990

3-[(1-Methyl-1H-tetrazol-5-y)thiomethyl] is one of the most important side chains in cephaloporins. This side chain which occures in numerous antibacterial agents, suc as cefamandole, latamoxef, cefoperazone, and cefmenoxime, contributes remarkable potency and broad spectrum. For the continuous work of study on the development of broad spectrum cephalosporins, we become interested in the effect of structural modification of the substituent at the N-1 position of mercaptoterazole toward biological activity because our recent work had demonstraated that the arylsubstituted mercaptotetrazoles (Fig. 1) had favorable effect on the activity against gram-positive bacteria. The main focus of this report was to investigate the relationship between activity and functional groups in the mercaptotetrazole.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3605-3610
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• 2010

In the present study, some quinoline derivatives have been synthesized like 8-methoxy-4-methyl-2-amino-(3'-chloro-2'-oxo-4'-substituted aryl-1'-azetidinyl)quinolines 8-12 and 8-methoxy-4-methyl-2-amino-(2'-substituted aryl-4'-oxo-1',3'-thiazolidin-3'-yl) quinolines 13-17 from 8-methoxy-4-methyl-2-(substituted arylidenyliminoamino)-quinolines 3-7. The structural assignments of these compounds were based on spectral (IR, $^1H$-NMR, Mass) and elemental (C, H, N) analysis. Further, these compounds were evaluated for antibacterial activity against various bacterial strains. Three compounds 10, 11 and 16 were found to exhibit potent antibacterial activity as compared to the standard drug amphicillin.

• Bulletin of the Korean Chemical Society
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• v.13 no.4
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• pp.381-384
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• 1992

The hydrolytic susceptibility of large unilamellar vesicle (LUV) toward cabbage phospholipase D (PLD) was studied. The activity of PLD was determined by pH stat titration method. Using phosphatidylcholine LUV as substrate a pH optimum of 6.96 was observed. For maximal activity the optimal temperature of $31^{\circ}C$ and 10 mM of Ca2+ were required. The apparent Km value estimated was 2.5 mM. The hydrolytic activity of PLD toward PC LUV was somewhat high despite the absence of activator in assay system and this high susceptibility of PC LUV may be attributed to the structural properties of LUV. The effect of amphiphatic substances such as dicetyl phosphate and phosphatidic acid on the enzyme activity were also examined in mixed LUVs.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.205-213
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• 2015

This study aims to verify the structural correlation empirically between information security performance and information management performance. To verify the correlation, three factors such as managerial controlled activity, technical controlled activity, and physical controlled activity are divided for the information security activities variable. the security performance are divided into accident prevention and accident response variables. As a result, security organization activity is a unique factor being positively significant to information security and management performance. And three activities such as human security, security training, development security do not affect at all on both information security and management performance.

• BMB Reports
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• v.34 no.1
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• pp.73-79
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• 2001

Transcriptional activation domains are known to be inherently "unstructured" with no tertiary structure. A recent NMR study, however, has shown that the transactivation domain in human p53 is populated with an amphipathic helix and two nascent turns. This suggests that the presence of such local secondary structures within the overall "unstructured" structural framework is a general feature of acidic transactivation domains. These pre-existing local structures in p53, formed selectively by positional conserved hydrophobic residues that are known to be critical for transcriptional activity, thus appear to constitute the specific structural motifs that regulate recognition of the p53 transactivation domain by target proteins. Here, we report the results of a NMR structural comparison between the native human p53 transactivation domain and an inactive mutant (22L,23W$\rightarrow$22R,23S). Results show that the mutant has an identical overall structural topology as the native protein, to the extent that the amphipathic helix formed by the residues 18T 26L within the native p53 transactivating domain is preserved in the double mutant. Therefore, the lack of transcriptional activity in the double mutant should be ascribed to the disruption of the essential hydrophobic contacts between the p53 transactivation domain and target proteins due to the (22L,23W$\rightarrow$22R,23S) mutation.

• Economic and Environmental Geology
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• v.37 no.5
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• pp.543-554
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• 2004

Analysis of multi-channel seismic reflection and well data serves to detail the structural evolution of the northern Okinawa Trough, southern offshore Korea. The overall structural style of the area is characterized by a series of half grabens and tilted fault blocks bounded by basement-involved listric normal faults. Most half grabens and tilted fault blocks developed in the direction of NNE-SSW, parallel to the axis of the Okinawa Trough. Orientation and distribution of the listric faults also suggest the development of transfer faults in NW-SE direction. The rifting phase of the northern Okinawa Trough have been established on the basis of structural and stratigraphic analyses of depositional sequences and their seismic expressions. Major phase of rifting probably started in the Late Miocene and the most active rifting occurred during the Early Pliocene. The rifting produced a series of half grabens and tilted fault blocks bounded by listric normal faults. It appears that the rifting activity has become weaker since the Late Pliocene, but the Pleistocene sediments faulted by listric faults bounding tilted fault blocks suggest that the rifting activity is probably still in progress.

• BMB Reports
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• v.35 no.2
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• pp.155-164
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• 2002

The structural aspects of ervatamin B have been studied in different types of alcohol. This alcohol did not affect the structure or activity of ervatamin B under neutral conditions. At a low pH (3.0), different kinds of alcohol have different effects. Interestingly, at a certain concentration of non-fluorinated, aliphatic, monohydric alcohol, a conformational switch from the predominantly $\alpha$-helical to $\beta$-sheeted state is observed with a complete loss of tertiary structure and proteolytic activity. This is contrary to the observation that alcohol induces mostly the $\alpha$helical structure in proteins. The O-state of ervatamin B in 50% methanol at pH 3.0 has enhanced the stability towards GuHCl denaturation and shows a biphasic transition. This suggests the presence of two structural parts with different stabilities that unfold in steps. The thermal unfolding of ervatamin B in the O-state is also biphasic, which confirms the presence of two domains in the enzyme structure that unfold sequentially. The differential stabilization of the structural parts may also be a reflection of the differential stabilization of local conformations in methanol. Thermal unfolding of ervatamin B in the absence of alcohol is cooperative, both at neutral and low pH, and can be fitted to a two state model. However, at pH 2.0 the calorimetric profiles show two peaks, which indicates the presence of two structural domains in the enzyme with different thermal stabilities that are denatured more or less independently. With an increase in pH to 3.0 and 4.0, the shape of the DSC profiles change, and the two peaks converge to a predominant single peak. However, the ratio of van't Hoff enthalpy to calorimetric enthalpy is approximated to 2.0, indicating non-cooperativity in thermal unfolding.