• 폴리머
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• 제38권2호
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• pp.220-224
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• 2014

콘택트렌즈용 하이드로젤로의 단백질 흡착량을 시간에 따라 분석하여 계면으로 확산되는 단백질 흡착 반응속도를 연구하였다. HEMA(hydroxyethylmethacrylate)계열 하이드로젤과 silicone계열 하이드로젤을 단백질(알부민 또는 IgG)용액에 침지시킨 후 단백질 흡착량을 시간에 따라 측정하였다. 모든 하이드로젤로의 단백질 흡착량은 단시간(10분)에 급격히 증가한 후 90분 동안 변화 없이 일정하였다. 빠른 단백질 분자의 확산에도 불구하고 계면에너지 감소는 한 시간 이상 진행되는데 이는 계면 탈수 현상이 한 시간 이상 진행되기 때문으로 이해된다. 계면에너지와 단백질 흡착량의 상관관계를 이해하여 콘택트렌즈 재질로의 단백질 흡착 반응 속도의 메커니즘을 분석하였다.

• Journal of Korean Neurosurgical Society
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• 제60권4호
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• pp.391-396
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• 2017

Objective : To investigate the neuroprotective effects of Ginkgolide B (GB) against ischemic stroke-induced injury in vivo and in vitro, and further explore the possible mechanisms concerned. Methods : Transient middle cerebral artery occlusion (tMCAO) mice and oxygen-glucose deprivation/reoxygenation (OGD/R)-treated N2a cells were used to explore the neuroprotective effects of GB. The expression of brain-derived neurotrophic factor (BDNF) was detected via Western blot and qRT-PCR. Results : GB treatment (4 mg/kg, i. p., bid) significantly reduced neurological deficits, water content, and cerebral infarct volume in tMCAO mice. GB also significantly increased Bcl-2/Bax ratio, reduced the expression of caspase-3, and protected against OGD/R-induced neuronal apoptosis. Meanwhile, GB caused the up-regulation of BDNF protein in vivo and in vitro. Conclusion : Our data suggest that GB might protect the brain against ischemic insult partly via modulating BDNF expression.

• 대한한방내과학회지
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• 제25권3호
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• pp.461-472
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• 2004

Objectives : For the screening of neuroprotective effects of medicinal herbs, the complex system of animal models suffer some disadvantages in controlling critical parameters such as blood pressure and body temperature. Additionally, application of drugs to the appropriate brain area sometimes is difficult, due to poor permeability though the blood brain barrier, and so potential protective effects might be masked. Methods : Organotypic hippocampal slice culture (OHSC) method has the advantages of being relatively easy to prepare and of maintaining the general structure, including tissue integrity and the connections between cells. Drugs can easily be applied and neuronal damage can easily be quantified by using tissues and culture media. This study demonstrates neuroprotective effects of Puerariae radix (葛根, PR), Salviae miltiorrhizae radix (丹蔘, SR), Rhei rhizoma (大黃, RR), and Bupleuri radix (柴胡, BR). These were screenedand compared to MK-801, antagonist of NMDA receptors, by using OHSC of 1 week-old Sprague-Dawley rats. Oxygen/glucose deprivation (OGD) were conducted in an anaerobic chamber $(85%\;N_2,\;10%\;CO_2\;and\;5%\;H_2)$ in a deoxygenated glucose-free medium for 60 minutes. Water extracts of each herbs were treated to culture media with $5\;{\mu}g/ml$ for 48 hours. Results : Neuronal cell death in the cultures was monitored by densitometric measurements of the cellular uptake of propidium iodide (PI). PI fluorescence images were obtained at 48 hours after the OGD and medicinal herb treatment. Also TUNEL-positive cells in the CAI and DG regions and LDH concentrations in culture media were measured at 48 hours after the OGD. According to measured data, MK-801, PR, SR and BR demonstrated significant neuroprotective effect against excessive neuronal cell death and apoptosis induced by the OGD insult. Especially, PR revealed similar neuroprotective effect to MK-801 and RR demonstrated weak neuroprotective effect. Conclusions : These results suggest that OHSC can be a suitable method for screening of neuroprotective effects of medicinal herbs. (This work was supported by the research program of Dongguk University and Grant 01-PJ9-PG1-01CO03-0003 from Ministry of Health & Welfare.)

• Plant Biotechnology Reports
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• 제4권3호
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• pp.213-222
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• 2010

Within their natural habitat, crops are often subjected to drought and heat stress, which suppress crop growth and decrease crop production. Causing overaccumulation of glycinebetaine (GB) has been used to enhance the crop yield under stress. Here, we investigated the response of wheat (Triticum aestivum L.) photosynthesis to drought, heat stress and their combination with a transgenic wheat line (T6) overaccumulating GB and its wild-type (WT) Shi4185. Drought stress (DS) was imposed by controlling irrigation until the relative water content (RWC) of the flag leaves decreased to between 78 and 82%. Heat stress (HS) was applied by exposing wheat plants to $40^{\circ}C$ for 4 h. A combination of drought and heat stress was applied by subjecting the drought-stressed plants to a heat stress as above. The results indicated that all stresses decreased photosynthesis, but the combination of drought and heat stress exacerbated the negative effects on photosynthesis more than exposure to drought or heat stress alone. Drought stress decreased the transpiration rate (Tr), stomatal conductance (Gs) and intercellular $CO_2$ concentration (Ci), while heat stress increased all of these; the deprivation of water was greater under drought stress than heat stress, but heat stress decreased the antioxidant enzyme activity to a greater extent. Overaccumulated GB could alleviate the decrease of photosynthesis caused by all stresses tested. These suggest that GB induces an increase of osmotic adjustments for drought tolerance, while its improvement of the antioxidative defense system including antioxidative enzymes and antioxidants may be more important for heat tolerance.

• Molecules and Cells
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• 제27권4호
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• pp.409-416
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• 2009

ADAP is an AP2-domain protein that interacts with ARIA, which, in turn, interacts with ABF2, a bZIP class transcription factor. ABF2 regulates various aspects of the abscisic acid (ABA) response by controlling the expression of a subset of ABA-responsive genes. Our expression analyses indicate that ADAP is expressed in roots, emerging young leaves, and flowers. We found that adap knockout mutant lines germinate more efficiently than wild-type plants and that the mutant seedlings grow faster. This suggests that ADAP is involved in the regulation of germination and seedling growth. Both germination and post-germination growth of the knockout mutants were partially insensitive to ABA, which indicates that ADAP is required for a full ABA response. The survival rates for mutants from which water was withheld were low compared with those for wild-type plants. The result shows that ADAP is necessary for the response to stress induced by water deprivation. Together, our data indicate that ADAP is a positive regulator of the ABA response and is also involved in regulating seedling growth. The role of ADAP is similar to that of ARIA, which is also a positive regulator of the ABA response. It appears that ADAP acts through the same ABA response pathway as ARIA.

• 한국동물위생학회지
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• 제24권4호
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• pp.379-382
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• 2001

To confirm the effect of food and water deprivation prior to Newcastle disease(ND) virus vaccination, three hundred chicks were divided into five groups with three replications. ND vaccine were sprayed to at 1 -day old chicks at commercial hatchery. Secondary and third vaccination was conducted at 2-week old and 24-day old chicks by LaSota strain. Control was conventionally vaccinated without withdrawing the food and water before or after vaccination. In group 2(G2) and 3(G3), LaSota strain was vaccinated to chicks before and after fasting the food and water for 3 and 2 hours, respectively. Group 4(G4) has the same fasting time of group 2, but supplemented the skim milk in vaccin dilution water. In group 5(G5), skim milk was added into group 3. Weight gain, feed intake and feed conversion were weekly measured for 5 weeks. Blood was collected from wing vein at 24 and 35 days of age. Each serum antibody level were measured by hemagglutination inhibition(HI) test. The average weight gain, feed intake, feed conversion of all group were not significantly different. Weight gain of each groups was 1910.30(control), 1875.28(G2), 1952.12(G4) and 1896.05(G5), respectively. Feed intake of all group was recorded at 3160.67(control), 3167.07(G2), 3189.48(G3), 3157.85(G4) and 3178.16(G5), respectively. The feed conversion of each groups was 1.655(control), 1.688(G2), 1.633(G3), 1.699(G4) and 1.676(G5), respectively. The HI titer of G4 was $ 5.50{\Pm}$1.40 and significantly higher than the other groups (p<0.05)(control : $4.36{\Pm}$1.87 , G2 : $5.18{\Pm}$2.14, G3 : $4.51{\Pm}$2.19, G : $5.28{\Pm}$1.58 at 35 days old. The results of this experiment indicated that two or three hours of fasting time before or after vaccination would be able to show the higher antibody level against ND virus.

• Journal of Ginseng Research
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• 제44권3호
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• pp.442-452
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• 2020

Backgroud: Sleep deprivation (SD) impairs learning and memory by inhibiting hippocampal functioning at molecular and cellular levels. Abnormal autophagy and apoptosis are closely associated with neurodegeneration in the central nervous system. This study is aimed to explore the alleviative effect and the underlying molecular mechanism of stem-leaf saponins of Panax notoginseng (SLSP) on the abnormal neuronal autophagy and apoptosis in hippocampus of mice with impaired learning and memory induced by SD. Methods: Mouse spatial learning and memory were assessed by Morris water maze test. Neuronal morphological changes were observed by Nissl staining. Autophagosome formation was examined by transmission electron microscopy, immunofluorescent staining, acridine orange staining, and transient transfection of the tf-LC3 plasmid. Apoptotic event was analyzed by flow cytometry after PI/annexin V staining. The expression or activation of autophagy and apoptosis-related proteins were detected by Western blotting assay. Results: SLSP was shown to improve the spatial learning and memory of mice after SD for 48 h, accomanied with restrained excessive autophage and apoptosis, whereas enhanced activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway in hippocampal neurons. Meanwhile, it improved the aberrant autophagy and apoptosis induced by rapamycin and re-activated phosphoinositide 3-kinase/Akt/mammalian target of rapamycin signaling transduction in HT-22 cells, a hippocampal neuronal cell line. Conclusion: SLSP could alleviate cognitive impairment induced by SD, which was achieved probably through suppressing the abnormal autophagy and apoptosis of hippocampal neurons. The findings may contribute to the clinical application of SLSP in the prevention or therapy of neurological disorders associated with SD.

• 동의신경정신과학회지
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• 제28권3호
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• pp.287-302
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• 2017

Objectives: To evaluate effects of Resina Dendropanacis Morbiferus (RDM) on stress and sleep hormones when administered to Chronic Mild Stressed (CMS) rats. Methods: Twenty-five healthy rats were randomly divided into 5 groups; Normal, CMS (Control), Resina Dendropanacis Mobiferus 50 mg/kg (RDM 50), 100 mg/kg (RDM 100), and 200 mg/kg (RDM 200). All rats except the normal group were exposed to unpredicted stress conditions such as water deprivation, empty bottles, forced thread mill, etc. according to timetable of CMS for 3 weeks. After a week starting experiments, rats in RDM 50, RDM 100, and RDM 200 groups were fed orally once a day for 2 weeks. Afterward, blood samples were taken from rats to analyze complete blood count, AST, ALT, and glucose. Noradrenalin, GABA and Melatonin were measured by ELISA kit. BDNF, CREB and TrkB were measured by RT-PCT. Results: 1. In Noradrenalin content, RDM 100 and RDM 200 groups revealed significant decrease compared to the control group. 2. In GABA content, RDM 50 and RDM 100 groups revealed significant decrease compared to the control group. 3. In Melatonin content, RDM 100 and 200 groups revealed significant decrease compared to the control group. 4. In Activity of BDNF, RDM 100 and 200 groups revealed significant increase compared to the control group. 5. In Activity of CREB and TrkB, RDM 100 group revealed significant increase compared to the control group. 6. In Erythrocyte and Thrombocyte changes, red blood cells and hematocrit significantly increased in RDM 50 and RDM 200 groups than the control group. Hemoglobin and platelet significantly increased in all experimental groups and the control group. 7. In Weight gain content, all RDM groups revealed insignificant increase compared to the control group. 8. In Glucose content, RDM 50, RDM 100, and RDM 200 groups revealed significant decrease compared to the control group. Conclusions: Results suggest that RDM have effects on stress and sleep hormones when administered to Chronic Mild Stressed (CMS) rats.

• Toxicological Research
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• 제22권3호
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• pp.275-282
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• 2006

In previous our studies, we have reported that eugenol derived from Eugenia caryophyllata(Myrtaceace) exhibits acute N-methyl-D-aspartate(NMDA)- and oxygen/glucose deprivation-induced neurotoxicity in primary cortical cultures and protects hippocampal neurons from global ischemia. In this study, we investigated whether the extracts and fractions of E. caryophyllata or eugenol shows the neuroprotective effects against delayed neuronal injury evoked by NMDA or ${\alpha}$-amino-3-hydroxy-5-methylisoxazole propionate(AMPA), and oxidative damage induced by arachidonic acid-, hydrogen peroxide-, $FeCl_2$/ascorbic acid-, and buthionine sulfoximine(BSO) in primary cortical cultures. We examined the neurotoxicity of eugenol itself in cultures and inhibitory effect of eugenol on NMDA- or kainate(KA)-induced convulsion in BALB/c mice. Each water, methanol extract and methanol fraction of E. caryophyllata was significantly attenuated NMDA-induced delayed neurotoxicity, respectively. Eugenol exhibited a significant inhibitory action against the convulsion evoked by NMDA and KA, and reduced delayed or brief neurotoxicity induced by NMDA, AMPA, and various oxidative injuries. These results suggest that eugenol derived from E. caryophyllata may contribute the neuroprotection against delayed-type excitotoxicity and excitotoxins-mediated convulsion through the amelioration of oxidative stress.

• 대한약리학회지
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• 제20권2호
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• pp.1-6
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• 1984

It has been generally recognized that the secretion of aldosterone is mainly regulated by angiotensin II in animals and humans, however, potassium and ACTH are also proposed as other humoral factors involved in the aldosterone secretory process. Recently, stress, anesthesia, adrenergic stimulation, low sodium intake or water deprivation stimulate plasma renin activity, while high sodium intake and deoxycorticosteroid have been reported to cause suppression of renin activity in animals. It seems that overall response of aldosterone secretory mechanisms reflects complex interactions both intrarenal and extrarenal components. Furosemide has been widely used to investigate the control of renin secretion by the kidney, and the relationship between diuretics and the disposition of endogenous aldosterone were reported (Oh, 1984). The sequential with 10 min interval samples of plasma were collected following administration of furosemide(1 mg/kg), aspirin(10 mg/kg), respectively. And also similar experiment was performed in the propranolol (10 mg/kg) pretreated rabbits. The results were as follows : 1) The concentration of plasma aldosterone was average of $426.I{\sim}485.5pg/ml$ in normal rabbits. Plasma concentrations of aldosterone rised significantly after injection of furosemide during 50 min, and the rise of plasma aldosterone was blocked by the propranolol pretreatment 2) Significant fall in the plasma level of aldosterone after injection of aspirin was noted. This result indicates that the increased secretion of aldosterone induced by furosemide administration is mediated through ${\beta}-receptors$, and the possible role of prostaglandin is substantiated.