• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.259.2-259
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• 1997

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.219.1-219
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• 1999

No Abstract, See Full Text

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.64-68
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• 1998

Three anthraquinones, chrysophanol, physcion and 1-o-methyl-2-methoxychrysophanol which have $Na^+,K^+-ATPase$ and cyclic AMP phosphodiesterase lowering activities related to cardiotonic action were isolated from the Korean marine echiura, Urechis unicintus. Spectroscopic methods, including HMQC, HMBC and NOE studies, were used to establish the structures.

• The Korean Journal of Mycology
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• v.21 no.3
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• pp.165-171
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• 1993

The effects of the iron ions for the light-induced mitochondrial $F_0F_1-ATPase$ of Lentinus edodes was studied. The enzyme activity was stimulated up to 202% by 0.1 mM $Fe^{2-}$ ion, but was inhibited by $Fe^{3+}\;and\;Mg^{2+}$. In the presence of 0.5 mM $Mg^{2+}$, the activity also increased 32% by 0.1 mM $Fe^{2+}$ ion, and decreased to a similar extent by $Fe^{3+}$ ion than by only $Fe^{3+}$ ion. Also, the activity was inhibited 53% by 5.0 mM $Fe^{2-}$ ion in the presence of 0.5 mM $Mg^{2+}$ ion and various concentration of $Fe^{3+}$ ion(mM). These results showed that $Fe^{2+}$ strongly stimulated the enzyme activity and its role for the enzyme was independent of $Mg^{2+}$ ion, but was dependent of $Fe^{3+}$ ion. From inactivation of the enzyme by addition of metal chelating agent, EDTA, it is suggested that the enzyme is to be metalloenzyme. The optimal pH and temperature of the enzyme in the presence of 0.1 mM $Fe^{2+}$ was 7.6 and $63^{\circ}C$, respectively.

• The Korean Journal of Pharmacology
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• v.24 no.2
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• pp.179-187
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• 1988

Verapamil, tetrodotoxin and tetraethylammonium chloride in the stated amount did not affect the $Na^{++}$ induced $Ca^{++}$ release. $Cd^{++}$ and $Zn^{++}$ significantly inhibited the $Na^{++}$ induced $Ca^{++}$ release. $Mn^{++}$ also inhibited $Na^+-Ca^{++}$ exchange. $Cd^{++}$ inhibited $Na^+-Ca^{++}$ exchange noncompetitively with an apparent inhibition constant (Ki) of $100\;{\mu}M$. $Cd^{++}$ caused loss of sulfhydryl group, whereas $Zn^{++}$ did not show any significant effect. $Cd^{++}$ and $Zn^{++}$ effectively inhibited $Na^+-Ca^{++}$ ATPase and slightly inhibited $Ca^{++}-Mg^{++}$ ATPase. Carbonyl cyanide chlorophenylhydrazone, 2,4-dinitrophenol and sodium arsenate stimulated the $Na^{++}$ induced $Ca^{++}$ release. Dibucaine and oligomycin slightly inhibited it. The results suggest that the $Na^+-Ca^{++}$ exchange on the synaptosomal plasma membrane may be not accomplished by ion channels. The $Na^+-Ca^{++}$ exchange is sensitively inhibited by $Cd^{++}$ and this transport process appears to be partially regulated by sulfhydryl groups of the synaptosomal plasma membrane. It is also postulated that $Na^+-Ca^{++}$ exchange is suppressed during the phosphorylation reaction of protein component on the neuronal membrane.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1399-1403
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• 1998

We isolated wild lactic acid bacteria from kimchi and identified as Lactobacillus brevis by using API 50 CHL Kit, some morphological and physiological tests. In order to evaluate the acid tolerance of Lactobacillus brevis, its survivals rate, glycolysis assay, membrane permeability, and pH profiles of $H^+-ATPase$ were also determined. When Lactobacillus brevis were incubated in Lactobacilli MRS broth adjusted to various levels of pH for 2 hours, the decreases in its population at pH 4.0 and 3.0 were about 2.61 log cycles/mL and 5.89 log cycles/mL, respectively, but there was no decrease at pH 6.0 and 5.0. Glycolysis by Lactobacillus brevis had optimal pH about 6.5 and glucose degradation was reduced by 50% at a pH of 5.2. $Mg^{++}$ release from Lactobacillus brevis cells in medium with pHs of 4.0 and 3.0 was 24.3 and 71.2% of totals, respectively. The $H^+-ATPase$ of Lactobacillus brevis showed a maximal activity between pH values of approximately 6.5 to 7.0.

• Applied Microscopy
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• v.12 no.1
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• pp.57-68
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• 1982

Cyclical changes in the fine structures of endometrial stroma of guinea pig during the estrous cycle were studied by electron microscopy. Cytochemical studies were made in order to investigate the ultrastructural localization of the acid phosphatase,alkaline phosphatase and ATPase in these cells. The results obtained are as follows: 1. During estrus collagen fibers were most abundant in the stroma. The stromal cells showed increases in the number of several cytoplasmic organelles, especially the rough endoplasmic reticulum was significantly increased and the structures were greatly differentiated. 2. Many cytoplasmic processes and cell debris have been distributed in the stroma of metestrus. The distributions were increased and degenerated mitochondria were observed during diestrus. 3. Cytochemical studies indicated that during metestrus and diestrus acid phosphatase activities were localized in the degenerating collagen fibers. Alkaline phosphatase activities were weak in the collegen fibers during proestrus and estrus which intense activities were localized around the cell membrane during metestrus and diestrus. ATPase activities were present on the cell membrane and intercellular space of stromal cell during proestrus and estrus.

• BMB Reports
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• v.47 no.5
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• pp.292-297
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• 2014

Age-related macular degeneration (AMD) is the leading cause of blindness in the world. Evidence indicates that the suppression of the ubiquitin-proteasome system (UPS) contributes to the accumulation of toxic proteins and inflammation in retinal pigment epithelium (RPE), the functional abnormalities and/or the degeneration of which are believed to be the initiators and major pathologies of AMD. To identify new protein associations with the altered UPS in AMD, we used LC-ESI-MS/MS to perform a proteomic analysis of the aqueous humor (AH) of AMD patients and matched control subjects. Six UPS-related proteins were present in the AH of the patients and control subjects. Four of the proteins, including 26S proteasome non-ATPase regulatory subunit 1 (Rpn2), were increased in patients, according to semi-quantitative proteomic profiling. An LC-MRM assay revealed a significant increase of Rpn2 in 15 AMD patients compared to the control subjects, suggesting that this protein could be a biomarker for AMD.

• Archives of Pharmacal Research
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• v.22 no.2
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• pp.137-142
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• 1999

Anti-ulcer activity of newly synthesized acylquinoline derivatives was investigated. For the in vitro screening, the effects of compounds on gastric $H^{+}/K^{+}$ ATPase isolated from hog and rabbit were examined. Among them, AU-090, AU-091, AU-254, AU-413 and AU-466 exhibited good in vitro activity on both enzymes. To correlate the in vitro activity with in vivo action, the effects of the compounds on the basal gastric acid secretion were studied. Some derivatives showed considerable anti-secretory activities, and AU-413 was selected for further studies. AU-413 protected gastric damage induced by either ethanol or NaOH dose dependently when given orally. $ED_{50}$ values of 12 mg/kg, p.o. (ethanol) and 41 mg/kg, p.o. (NaOH) were obtained. In addition, histamine-stimulated gastric secretion was reduced upon AU-413 administration. Taken together, newly synthesized acylquinoline derivatives, especially AU-413, is worthy of further investigation to be developed as an anti-ulcer agent.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.100-100
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• 1997

To treat peptic ulcer diseases, many potent proton pump inhibitors have been developed for suppressing the gastric acid secretion in clinical patients. However, most of these agents have common irreversible mechanisms against H$\^$+/, K$\^$+/-ATPase which might be the cause of hypergastrinemia and ECL cell hyperplasia. Therefore, the development of new reversible inhibitors is prompted. In this study, we investigated the inhibitory mechanism of a newly synthesized proton pump inhibitor, YJA20379-8 using lyophilized hog gastric microsomes. YJA20379-8 inhibited K$\^$+/-stimulated H$\^$+/K$\^$+/-ATPase activity uncompetitively with respect to K$\^$+/, and in the other hand, showed competitive inhibitory pattern with ATP, respectively. From these data, we suggest that YJA20379-8 may be a proton pump inhibitor with a new inhibitory mechanism.