• Korean Journal of Pharmacognosy
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• v.30 no.1
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• pp.25-33
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• 1999

In order to find less toxic antiviral agents from basidiomycetes, EA, the water soluble substance, was prepared from the carpophores of Elfvingia applanata (Pers.) Karst. EA was examined for antiviral activity against five strains of pathogenic viruses such as encephalomyocarditis virus (EMCV), vesicular stomatitis virus (VSV) Indiana and New Jersey strains, influenza A virus (Flu A), and varicella zoster virus (VZV) in vitro. Antiviral activity was evaluated by plaque reduction assay. Among five strains of viruses tested, EA exhibited the most potent antiviral activity against VSV Indiana strain with 50% effective concentration $(EC_{50})$ of 0.104 mg/ml in Vero cells, and its selectivity index (SI) was 36.5. EA was also examined for the virucidal activity, antiviral activity in preincubation on VSV Indiana strain in order to examine possible mode of antiviral activity. Preincubation of Vero cells with EA did not confer protection against VSV, however, prolonged exposure of cells to EA inhibited the replication of virus dose-dependently. In virucidal activity, the titer of infectious virus did not decrease significantly.

• Environmental Analysis Health and Toxicology
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• v.13 no.1_2
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• pp.1-9
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• 1998

The ROS-producing potency of chromium compounds of several oxidation states were determined in the H4 cells. $K_2Cr_2O_7$ as Cr (VI), synthetic Cr (V) compounds and Cr (III) as TPP produced high level of ROS. However, ROS values of Cr-picolinate as Cr (III), CrCl$_2$, CrCI$_2$, were almost equal to the control. The effects of physiological antioxidants compounds which react with free radicals were examined for their effects on chromate-induced production of reactive oxygen species (ROS) in A549 cells after the addition of $K_2Cr_2O_7$. The compounds used were vitamin C (ascorbate), vitamin E ($\alpha$-tocopherol), superoxide dismutase (SOD) and catalase. The preincubation of ascorbate (200uM) with A549 cells for 20hr resulted in a significant reduction of hexavalent chromate(100uM) induced ROS. However, there is no effects of preincubation of the cells with vitamin E succinate (10 and 20uM, 20hr) on the ROS production. Also, the effects of Cr (VI) on the cell cycle of A549 cells was measured by adding the DNA intercalating agent, propidium iodide. S phase of the cell cycle was increased by the chromium (VI) compounds up to 20uM indicating toxicity or possible mitogenic action of the cell. The shoulder in Go/G1 phase at 20uM Cr (VI) with 24 hr treatment indicates apoptosis.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.1
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• pp.87-92
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• 2001

Carbon monoxide (CO) binds to soluble guanylate cyclase to lead its activation and elicits smooth muscle relaxation. The vascular tissues have a high capacity to produce CO, since heme oxygenase-2 (HO-2) is constitutively expressed in endothelial and smooth muscle cells, and HO-1 can be greatly up-regulated by oxidative stress. Moreover, the substrate of HO, heme, is readily available for catalysis in vascular tissue. Although the activation of heme oxygenase pathway under various stress conditions may provide a defence mechanism in compromised tissues, the specific role of HO-1-derived CO in the control of aortic contractility still remains to be elucidated. The present study was done to determine the effect of HO-1 induction on the aortic contractility. Thus, the effects of incubation of aortic tissue with S-nitroso-N-acetylpenicillamine (SNAP) for 1 hr on the aortic contractile response to phenylephrine were studied. The preincubation with SNAP resulted in depression of the vasoconstrictor response to phenylephrine. This effect was restored by HO inhibitor or methylene blue but not by NOS inhibitor. The attenuation of vascular reactivity by preincubation with SNAP was also revealed in endothelium-free rings. $AlF4^--evoked$ contraction in control did not differ from that in SNP-treated group. These results suggest that increased production of CO was responsible for the reduction of the contractile response to phenylephrine in aortic ring preincubated with SNAP and this effect of SNAP was independent on endothelium.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.267-273
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• 1999

In this study we examined the potential for the synergistic augmentation of the antitumor activity of inflammatory mouse peritoneal macrophages by stimulation with protein A combined with $IFN-\gamma$. The moderate augmentative effect induced by preincubation with protein A was demonstrated to be concentration-dependent, whereas IFN-, had a very low activating effect. Following preincubation with both protein A and $IFN-\gamma$, a marked enhancement of macrophage activity was noted. In addition, based on the utilization of neutralizing antibody to TNF-$\alpha$ or the inhibition of NO Production, TNF-$\alpha$ and NO were proven to be involved as mediators during the activation of tumoricidal macrophages by protein A in combination with $IFN-\gamma$. We also demonstrated that supernatants from macrophages treated with protein A plus $IFN-\gamma$ contained both TNF-$\alpha$ and NO at markedly increased levels. Thus, tumor cell lysis in the combined system was mediated via TNF-$\alpha$ or NO. These results demonstrate the synergistic effects on mouse pertioneal macrophage function of protein A in combination with $IFN-\gamma$ and suggest that combinations of such agents may serve as the basis for future in vivo immunotherapy.

• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.87-100
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• 1989

Eimeria tenella, an intracellular protozoan parasite infecting the epithelial cells of the ceca of chickens, causes severe diarrhea and bleeding that can lead its host to death. It is of interest that 2. tenezla first penetrate into the mucosal intraepithelial Iymphocytes (IEL) before they parasitize crypt or villous epithelial cells. This in vitro study was undertaken to know whether the penetration of E. tenella into such a lymphoid cell is a beneficial step for the parasite survival and development. Three sequential experiments were performed. First, the in vitro established bovine kidney cell line, MDBK cells, were evaluated for use as host cells for E. tenella, through morphological observation. Second, the degree of parasite development and multiplication in MDBK cells was quantitatively assayed using radioisotope labelled uracil ($^3H-uracil$) . Third, the E. tenella sporozoites viability was assayed after preincubation of them with thicken spleen cells. E. tenella oocysts obtained from the ceca of the infected chickens were used for the source of the sporozoites. Spleen cells (I) obtained from normal chickens (FP strain) were preincubated with the sporozoites (T) at the E:T ratio of 100:1, 50:1 or 25:1 for 4 or 12 hours, and then the mixture was inoculated into the MDBK cell monolayer. Morphologically the infected MDBK cells revealed active schisogonic cycle of E. tenella in 3~4 days, which was characterized by the appearance of trophozoites, and immature and mature schizonts containing merogoites. The 3H-uracil uptake by E. tenella increased gradually in the MDBK cells, which made a plateau after 48~60 hours, and decreased thereafter. The uptake amount of $^3H-uracil$ depended not only upon the inoculum sixte of the sporozoites but also on the degree of time delay (preincubation; sporozoites only) from excystation to inoculation into MDBK cells. The 3H-uracil uptake became lower as the preincubation time was prolonged. In comparison, after preincubation of sporozoites with spleen cells for 4 or 12 hours, the 3H-uracil uptake was significantly increased compared with that of control group. From the results, it was inferred that, although the penetration of E. tenella sporozoites into the lymphoid cells such as IEL is not an essential step, it should be at least a beneficial one for the survival and development of sporozoites in the chicken intestine.

• Journal of Environmental Science International
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• v.2 no.4
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• pp.255-270
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• 1993

Effects of polyamines on chlorophyll and protein content, and $\delta$-aminolevulinate dehydratase(ALAD) activity were investigated during the greening of mung bean cotyledons. Polyamines stimulated chlorophyll formation in greening cotyledons, and this effect was enhanced by KCl. The changes in protein content were similar to the changes for chlorophyll content. The excision entailed an increase in ALAD activity. Then a decrease appeared after 48 h incubation on water in the dark. It was more precocious in the light, but was accelerated when the cotyledons were illuminated after a dark preincubation. Putrescine had little effect on ALAD activity in the dark. In the light, putrescine prevented the decrease in ALAD activity and enhanced this activity when a dark preincubation preceded illumination. KCl had a slight stimulating effect in the dark, but was uneffective in the light. The combination putrescine＋KCl was devoid of stimulating effect. The results obtained suggest that plastid development of mung bean cotyledons during greening was affected by polyamines and light and that polyamines may play a role in the regulation of plastid development.

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.145-149
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• 2002

The effects of pH, temperature and various inhibitors on the proteolytic activity of the cell lysate of Uronema marium were investigated using colorimetric and substrate gel electro­phoretic methods. The cell lysate of U. marinum showed proteolytic activity over a wide range of pH, and pH optima ranged from pH 5 to 7. The proteolytic activity was increased according to a rise of temperature but decreased at $40^{\circ}$. The proteolytic activity of the parasite lysate was significantly inhibited by protease inhibitors including trans-epoxysuccinyl -L-leucylamido-(4-guanidino) butane (E-64), pepstatin A, phenyl-methanesulfonyl fluoride(PMSF), and ethylenediamine-tetraacetic acid (EDTA). Preincubation of the lysate with E-64 showed the maximum inhibition of the caseionolytic activity. Four protease bands (152, 97, 67 and 40 kDa) were detected by gelatin SDS-PAGE. Significant inhibition of caseinolytic activity and complete abolition of a 152 kDa band in gelatin SDS-PAGE by EDTA indicated that the cell lysate of U. marinum had a metalloprotease Another three proteolytic bands were inhibited by E64, a cysteine protease inhibitor. Preincubation of the cell lysate with pepstatin or PMSF had no effects on the protease bands.

• Archives of Pharmacal Research
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• v.9 no.2
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• pp.99-110
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• 1986

In order to use for metabolic studies of tranylcypromine (TCP), TCP-phenyl-$d_{5}$ was synthesized via the intermediates, 3-benzoylpropionic acid-$d_{5}$ and trans-2-phenylcyclopropanecarboxylic acid-$d_{5}$ -TCP(0.22 mmole/kg) and its deuterated analog were administered s. c. to the rats and GC/MS analyses of the urines led to the detection of N-acetyltranylcypromine (ATCP) and glucuronide conjugate of phenyl-hydroxylated ATCP. MAO activities in rat brain were measured using serotonin as the substrate. In vitro $IC_{50}$ of ATCP was determined to be $10^{-3}M$. The inhibitions by ATCP were not dependent on the preincubation time and were reversed by washing sedimented mitochondrial pellets after the preincubation. In vivo MAO inhibitions at various times of 0.5, 1.5, 3, 6, 12, and 23 hr after the administration of 0.4 mmole/kg (i. p. ) of ATCP were found to be 0.13, 73, 90, 89, and 74 %, respectively. Similarly, the inhibition percents by 0.015 mmole/kg (i. p. ) of TCP were 94, 99, 95, 91, 71 and 49%. The results strongly suggest that deacetylated product of ATCP may account for its in vivo MAO inhibition. The relationship between the metabolism via phenyl-hydroxylation and the in vivo potency of TCP was examined by QSAR study and it was found that groupings discriminating between the compounds with p-substituents and those without them only ensure high correlations, suggesting that ring-hydroxylation which occurs at the para position in most of the compounds is a determining factor to the potency of TCP.

• Korean Journal of Animal Reproduction
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• v.14 no.4
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• pp.245-252
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• 1990

This study was carried out to investigate the factors affecting fertilization in vitro of follicular oocytes with frozen-thawed spermatozoa in Korean Native Cattle. The bovine ovaries were obtained at a slaughter house and the follicular oocytes were recovered by aspirating the follicular fluid from the visible follicles of 3~6mm. The bovine oocytes were matured in vitro for 20~24 hours in TCM-199 containing FCS and hormones. The matured oocytes were fertilized in vitro using Percoll-separated frozen-thawed spermatozoa in BO solution. The effects of dilution and fertilization media, capacitating method, concentration of inseminated sperm and time after insemination of fertilization, were observed. The results obtained are summarized as follows : 1. The fertilization rate of frozen-thawed sperm inseminated in BO solution with caffeine and heparin together(56.4%) was higher than that of sperm inseminated in BO solution with either caffeine(10.5%) or heparin(8.9%) and without both caffeine and heparin(0%)(P<0.05). 2. The fertilization rate(56.3%) of frozen-thawed sperm inseminated in BO solution with both caffeine and heparin without preincubation was higher than that of sperm preincubated(2.9%)(P<0.05). 3. The fertilization with high concentration of frozen-thawed sperm(1.4~1.8$\times$107cells/ml) in BO solution containing caffeine and heparin resulted in higher fertilization rate, 76.7%, than the low concentration of sperm(0.8~1.0$\times$107cells/ml), 32.7%(P<0.01). 4. When the oocytes were inseminated with frozen-thawed sperm in BO solution containing caffeine and heparin without preincubation, fertilization rate increased by time and the rates were 5.9, 46.0 and 59.4% at 8, 16 and 24 hours, respectively.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.3
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• pp.315-322
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• 1998

The objective of this study was to test the effect of catalase on penetration in vitro by spermatozoa preincubated with xanthine and/or xanthine oxidase. The penetration rates were, significantly (p<0.05) higher in spermatozoa preincubated without (66 and 38%) than with (40 and 15%) catalase for 0 and 30 min. When spermatozoa were preincubated and inseminated in medium with xanthine, the penetration rates were significantly higher (p<0.05) in medium with (68, 70 and 49% for 0, 30 and 60 min) than without (33, 41 and 19% for 0, 30 and 60 min) catalase. However, in oocytes were' inseminated with spermatozoa pre incubated with or without catalase in the presence of xanthine oxidase, no decrease in penetrations rates were observed for up to 60 min of preincubation. In another experiment, the penetration rates were significantly (p<0.00l) higher in medium with (75, 55 and 52%) than without (14, 4 and 8%) catalase when oocytes were inseminated with spermatozoa preincubated for 0, 30 and 60 min in the presence of xanthine plus xanthine oxidase. On the other hand, The rate of polyspermy in oocytes penetrated in medium without catalase in the presence of xanthine or xanthine plus xanthine oxidase decreased with time of spermatozoa preincubation. However, no differences were observed in polyspermy rates in the medium with xanthine oxidase alone despite presence of catalase. These results indicate the advantages of spermatozoa pre incubated with xanthine plus xanthine oxidase in the presence of catalase to increase penetration potential and with suppressed polyspermy in porcine.