• Korean Journal of Agricultural Science
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• v.27 no.2
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• pp.86-94
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• 2000

This study was carried out to determine the effectiveness of uniconazole in ameliorating low and high temperature injury in tomato plants(Lycopersicon esculentum Mill. cvs. Fireball and Patio). Plants were given a soil drench of 0, 0.001, 0.01 or $0.1mg{\cdot}pot^{-1}$ uniconazole, and after 14 days, were treated with 12-h day/12-h night cycles at $25/25^{\circ}C$, $2.5/25^{\circ}C$, $25/2.5^{\circ}C$ or $40/40^{\circ}C$ for 4 days in controlled-environment chamber. Number of damaged leaves per plant, reduction of stem elongation, and overall injury were high at $2.5/25^{\circ}C$, but more reduction of leaf elongation, delay of flowering, and abortion of floral bud were observed in plants at $40/40^{\circ}C$. There was difference in degree of injury between cultivars, thus, 'Fireball' was much affected by unfavorable temperature regimes. All concentrations of uniconazole reduced leaf and stem elongation, increased total chlorophyll concentration, delayed flowering, and significantly provided protection against low and high temperature injury in two cultivars. In general, the application of uniconazole did not inhibit flowering delay and floral bud abortion induced by high and low temperature exposure. Our results support the hypothesis that the role of uniconazole is related to defense system against oxidative stress induced by low temperature stress. Further research is required to clarifu the phytoprotective mechanism of this compound agaist high temperature stress.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.409-414
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• 2004

Kojic acid is well known for its anti-pigmentation effect with tyrosinase inhibition activity. However, kojic acid is a unstable compound. In order to improve stability, kojic acid derivative, kojic acid $6-O-2',3',4',6'-tetraacetyl-{\beta}-D-glucopy-ranoside\;(KTGP)$, was synthesized with $O-pentaacetyl-{\beta}-D-glucose$ through the regio- and stereo-selective glycosylation of 6-OH group of kojic acid. High yield $(80\%)$ was obtained by the use of Lewis acid and organic base in nonpolar solvent. Hydrolysis of KTGP with the aid of sodium methoxide in methanol afforded kojic acid $6-O-{\beta}-D-glucopyranoside$ (KGP), which was confirmed by $^1H-NMR\;and\;^{13}C-NMR$ KGP is freely soluble in water and soluble in methanol and ethanol. Inhibition activity of KGP for tyrosinase was investigated by measuring the activity of mushroom tyrosinase compared with those of ascorbic acid, kojic acid, and arbutin. The free radical-scavenger activity was determined by the 1,1-diphenyl- 2-picrylhydrazyl (DPPH) assay. In toxicity assay, KGP was much less toxic than kojic acid and arbutin, Therefore, glycosylation of kojic acid may be useful for the development of stable kojic acid derivatives.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.33-40
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• 2000

This study was designed to clarify the mechanism of the inhibitory action of a nitric oxide (NO) donor, 3-morpholino-sydnonimine (SIN-1), on contraction, cytosolic $Ca^{2+}$ level $([Ca^{2+}]_i)$ and ionic currents in guinea-pig ileum. SIN-1 $(0.01{\sim}100\;{\mu}M)$ inhibited 25 mM KCl- or histamine $(10\;{\mu}M)-induced$ contraction in a concentration-dependent manner. SIN-1 reduced both the 25 mM KCl- and the histamine-stimulated increases in muscle tension in parallel with decreased $[Ca^{2+}]_i.$ Using the patch clamp technique with a holding potential of -60 mV, SIN-1 $(10\;{\mu}M)$ decreased peak Ba currents $(I_{Ba})$ by $30.9{\pm}5.4%$ (n=6) when voltage was stepped from -60 mV to +10 mV and this effect was blocked by ODQ $(1\;{\mu}M),$ a soluble guanylyl cyclase inhibitor. Cu/Zn SOD (100 U/ml), the free radical scavenger, had little effect on basal $I_{Ba},$ and SIN-1 $(10\;{\mu}M)$ inhibited peak $I_{Ba}$ by $32.4{\pm}5.8%$ (n=5) in the presence of Cu/Zn SOD. In a cell clamped at a holding-potential of -40 mV, application of $10\;{\mu}M$ histamine induced an inward current. The histamine-induced inward current was markedly and reversibly inhibited by $10\;{\mu}M$ SIN-1, and this effect was abolished by ODQ $(1\;{\mu}M).$ In addition, SIN-1 markedly increased the depolarization-activated outward $K^+$ currents in the all potential ranges. We concluded that SIN-1 inhibits smooth muscle contraction mainly by decreasing $[Ca^{2+}]_i$ resulted from the inhibition of L-type $Ca^{2+}$ channels and the inhibition of nonselective cation currents and/or by the activation of $K^+$ currents via a cGMP-dependent pathway.

• Journal of Chest Surgery
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• v.29 no.6
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• pp.593-598
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• 1996

The large number of past investigation on extended myocardial protection clearly indicates that cold potassium cardioplegia and topical cooling have limited capabilities. Accordingly, more recent experimen- tal approaches have focused on the modalities of reperfusion and their implication on postischemic myo- cardial recovery. Oxygen may play a crucial role in the development of ischemic and reperfusion injury. Reactive oxygen radicals may be produced during ischemia or reperfusion after incomplete reduction of molecular oxygen or from other pathway and then induce fatal injury of the heart. The important obser- vation of oxygen-induced myocardial damage during reperfusion has led to the concept of applying oxy- gen free radical scavengers. So, this study is on dietary vitamin C supplementation as antioxidant in rats to determine whether or not they have a higher tolerance against cardiac ischemia-reperf'usion injury under Langendorff system. Male or female Sprague-Dawley rats (190-33Og) were randomly separated into two groups. Group A was not treated(n=10). Group B received vitamin C supplement (n=10). Experiment was performed 24 hours after vitamin C 200mg fed orally as injectable ascorbic acid. There were significant differences in contractile parameters between control and vitamin C-treated group. The RLVP (r te of post/preischemic left ventricular pressure) and Rdp/dt (rate of post/preischemic dp/dt) were significant statistically between two groups (p<0.05). But, RHR (rate of post/preischemic heart rate), time to first beat and sta'utilization were not significant. In conclusion, pretreatment with the antioxidant, ascorbic acid, was found to preserve left ventricular contractile function. But the precise mechanism of action of ascorbic acid has not as yet been determined, so further study will be required.

• Journal of Yeungnam Medical Science
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• v.13 no.2
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• pp.243-250
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• 1996

Extravasation of toxic chemotherapeutic agents cause severe skin ulceration and necrosis which often need secondary surgical intervention. Still, there were not established antidote agent in case of extravasation with mitomycin-c. Dimethyl sulfoxide is known as an effective chemical scavenger of toxic hydroxyl free radical and sodium thiosulfate also was demonstrated significant protector from mitomycin-c induced ulceration by a few experimental studies. Author investigated necrotic area of mitomycin-c injected site and compare to the effectiveness of topical treatment with dimethyl sulfoxide and intradermal injection of sodium thiosulfate according to starting times, forty five mice were divided into 3 groups. Control group(n=5) had no treatment after subcutaneous injection of mitomycin-c. Experimental group I and II were 20 mice treated dimethyl sulfoxide and sodium thiosulfate, respectively. Depending on the starting time of treatment, group I and II were subdivided into 1, 2, 3 and 4 as immediate, 6 hours, 12 hours and 24 hours after mitomycin-c injection. Histologic studies of the necrotic area and survival area after treatment were performed using hematoxylin-eosin staining. The mean necrotic area of group I was significantly decreased depending on the starting time of treatment compared with control group(p<0.01). The results means there was no necrosis area which was treated with topical sodium thiosulfate within 6 hours, and it showed also significant decrease of necrosis area within 24 hours. There was also no necrosis area in group II-1 and significant decrease of necrosis area II-2 and III-3. But, effctiveness of intradermal injection of sodium thiosulfate was not found in group II-4 which was started after 24 hours. Hisotolgic findings showed a bland coagulative necrosis without inflammatory changes and no granulation tissue. The significant difference that cytoplasmic loss of subcutaneous fat and decrease number of hair follicles between two groups resulted from the methods of treatment by topical application and intradermal injection. In conclusion, immediate treatments with topical dimethyl sulfoxide or intradermal injection of sodium thiosulfate signifcantly prevents necrosis by extravasation of mitomycin-c.

• Journal of Veterinary Clinics
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• v.27 no.4
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• pp.348-365
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• 2010

Artemisia capillaries THUNB is a perennial herb that belongs to the family compositae spp. and the most common plant among the various herbal folk remedies used in treatment of abdominal pain, hepatitis, chronic liver disease, jaundice and coughing in Korea. The object of this study is to observe the dosage-dependent anti-obestic effects of an aqueous extracts of dried aqueous extracts of stems of Artemisia capillaris Thunberg. [Artemisiae capillaris Herba, In-Jin in Korean, INJ] on 45%/Kcal high fat diet (HFD) supplied mice. 45%/Kcal rodent HFD are supplied to ICR mice from 1 week before initiation of INJ administration throughout the 12 weeks, and after the end of 12 weeks of 62.5, 125 and 250 mg/kg/day of INJ administration, the efficacy was divided into five categories 1) hypoglycemic, 2) hepato-protective, 3) nephroprotective, 4) hypolipemic, and 5) anti- obesity effects. The effects were compared to those of simvastatin (for hypolipemic activity), silymarin (for hepatoprotective and free radical scavenger effects) and metformin (for hypoglycemic and related anti-obesity effects). 7 animals per group (8 groups; total 56adapted mice on HFD were selected base on the body weight at 6 days after initiation of HFD supply) were used in this experiment. INJ and all three different reference drugs were directly suspended or dissolved in distilled water, and administered at a volume of 10 mL/kg, once a day for 84 days from 1 week after HFD supply. As results of 91 days of continuous HFD supply, mice showed marked obese states, hyperglycemia, hyperlipemia, liver damages and kidney damages. These mean the obesity, diabetes, diabetic hepatopathies, nephropathies and hyperlipemia were induced by HFD supply. After end of 84 days of continuous treatment of three different dosages of INJ, all diabetes related complications were inhibited; relatively favorable anti-obesity, hypolipemic, hepatoprotective, hypoglycemic and nephroprotective effects. These favorable effects showed relatively good dose-relations between all three different dosages of INJ treated, and INJ 250 mg/kg showed enough favorable effects on diabetes and related four complications tested as compared with one of each three different references. Otherwise, the efficacy of 62.5 and 125 mg/kg of INJ was somewhat slighter than those of all three reference drugs. Therefore, the suitable effective dosage of INJ is considered as 250 mg/kg/day in the present study. The overall anti-obesity effects of INJ 250 mg/kg-treated group was similar or more favorable than those of metformin 250 mg/kg-treated group, and INJ 250 mg/kg showed slighter hypoglycemic effects with silymarin 100 mg/kg and metformin 250 mg/kg, similar hypolipemic effects with simvastatin 10 mg/kg, and similar hepatoprotective effects with silymarin 100 mg/kg, and similar nephroprotective effects with that of silymarin 100 mg/kg and metformin 250 mg/kg, respectively. Obese, hyperglycemia, hyperlipemia, steatohepatitis and related nephropathies induced by HFD supply were dramatically inhibited by 84 days of continuous treatment of all three different dosages of INJ. It is, therefore expected that INJ extracts will be a favorable alternative agent for diet-related diabetes and complications.