• The Korean Journal of Physiology
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• v.30 no.1
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• pp.97-104
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• 1996

Different neural substrates have been reported to be implicated in analgesic mechanisms in the acute phasic and the sustained tonic pains. To explore the differential antinociceptive action of diphenylhydantoin (DPH) and carbamazepine (CBZ) on the acute phasic and the tonic pains, changes in tail flick latency, hot plate latency and the formalin-induced nociceptive score were assessed prior to and after intraperitoneal administration of DPH (20 & 40 mg/Kg) and CBZ (20 mg/Kg). In 11 rats, CBZ was administered repeatedly for 6 days at the dose of 20 mg/Kg/day. Also studied were the effects of strychnine and picrotoxin (1 mg/Kg, i.p.) on the CBZ-produced changes in the formalin-induced pain behaviors. The tail flick and hot plate ltencies were not changes after administration of DPH and CBZ. However DPH strongly suppressed the formalin-induced tonic pain. A single and the repeated administration of CBZ inhibited both the early phasic and the late tonic pain responses to formalin in n similar manner. On the other hand, the antinociceptive actions of CBZ were not altered by strychnine or picrotoxin. These experimental findings lead to the conclusion that DPH and CBZ have differential antinociceptive action on the acute and the tonic pains and that their antinociceptive actions are independent of the GABA- and glycine-receptors.

• KSBB Journal
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• v.26 no.2
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• pp.177-181
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• 2011

This study was conducted to investigate the effects of gamma irradiation on the change of volatile flavor compounds of raw oyster and its cooking drips using headspace methods. Major volatile flavor compounds of the raw oyster were identified as methylthiomethane and 1,5-hexadiene. When the raw oyster was irradiated at the dose of 5 kGy, 1-pentane was newly detected. On the other hand, 9 compounds including N-methoxyformaldehyde were identified as the major volatile compounds of cooking drips from oyster. Among them, N-methoxyformaldehyde contents in cooking drip was decreased by the gamma irradiation. By the gamma irradiation above 30 kGy, new heterocyclic compounds was found in oyster cooking drips. Therefore, the amount of volatile flavor compounds in the raw oyster and cooking drips were changed by gamma irradiation, and these results could be potentially used in the seasoning industry.

• Journal of Pharmaceutical Investigation
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• v.30 no.4
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• pp.283-288
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• 2000

The purpose of the present study was to investigate the topical bioavailability of retinol (vitamin A) after its transdermal administration. For this purpose, we developed the convenient HPLC method to measure the retinol concentration in the biological fluids such as plasma and skin tissues. The low detection limit was $0.1\;{\mu}g/ml$ using a gradient HPLC system of UV detection. The initial plasma concentration of retinol was about $20\;{\mu}g/ml$ after its i.v. bolus administration (4.32 mg/kg). The half life $(t_{1/2{\alpha}})$ in the distributive phase was 1.3 min, while retinol was slowly disappeared in the post-distributive phase. On the other hand, the maximum plasma concentration $(C_{max})$ was about 776 ng/ml after appling to rat skin at a dose of 43.2 mg/kg. Furthermore, the concentration of retinol in the skin tissues was about 600 ng/g tissue at 12 hr after its transdermal administration. In conclusion, the initial plasma concentration of retinol was comparable with the skin concentration after its cutaneous absorption, followed by being decreased with the passage of the time.

• Toxicological Research
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• v.12 no.1
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• pp.21-27
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• 1996

Vitamin C has been well known to be a potential chemopreventive agent for several toxic compounds. It reduced the mutation frequencies of 6-sulfooxymethylbenzo[a]pyrene (SMBP) and 6hydroxymethylbenzo[a]pyrene (HMBP) in Salmonella typhimurium TA98 and TA100, indicating that corbic acid affects both frameshift and base-pair substitution mtltations. A similar type of dose-response relationship was shown in the V79 cells, although the inhibitory effect was less dramatic compared with that in S. typhimurium. However, SMBP or HMBP binding to calf thymus DNA was not affected by the presence of vitamin C, suggesting that SMBP seems to be much more reactive to calf thymus DNA than vitamin C. This was supported by migration pattern and fluorescence intensity of SMBP-modified plasmid on the gel. These restilts were not correlated with mutation tests in bacterial and mammalian cell systems. It has been already reported that vitamin C inactivates SMBP through the formation of covalently bound addact. It was found from HPLC analysis that the reaction between vitamin C and SMBP was accomplished within just 5 min and then produced the several products. These findings indicate that the beneficiary of vitamin C is not merely derived from the covalent adducts. On the other hand, the addition of DNA to incubation mixture reduced the amounts of vitamin C adducts while the magnitude of HMBP peak increased, suggesting that DNA accelerates the SMBP hydrolysis to intercept the interaction between SMBP and vitamin C or forms rapidly complex with SMBP.

• Preventive Nutrition and Food Science
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• v.6 no.4
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• pp.216-223
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• 2001

A study was carried out to examine the effect of sample form and storage conditions on the accumulated PPSL signals. Korean perilla and sesame seeds were tested as whole samples and separated minerals. Radiation-induced PPSL signals of perilla and sesame seeds themselves significantly increased with irradiation dose up to 5 kGy. On the other hand, a slight decrease in the accumulated PPSL signals was shown at 10 kGy. Similar results were also found in separated minerals. The accumulated PPSL signals of irradiated samples decreased with increasing storage periods. The decay rate was higher in 5 or 10 kGy-irradiated samples than in 1 kGy, in room conditions than in darkroom conditions, and in sesame and perilla seeds themselves than in separated minerals. The accumulated PPSL signals of the irradiated samples measured fur 120 s were higher than those measured for 60 s. These results indicated that although the PPSL signal of all samples decreased with increasing the storage time, detection of irradiated samples was still possible after 12 months of storage regardless of sample form and measurement times (60 and 120 s) in both room and darkroom conditions.

• Journal of Radiation Industry
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• v.5 no.1
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• pp.69-73
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• 2011

Polyamide 66 (PA66) nanofibers with Triallyl cyanurate (TAC) were obtained by electrospinning of formic acid and chloroform solution. Electron beam irradiation of PA66 nanofiber with and without TAC was carried out over a range of absorbed doses (20~100 kGy) in nitrogen. The characterization of the irradiated PA66 nanofibers and PA66 nanofibers with TAC was done by scanning electron microscopy (SEM), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA) and universal testing machine (UTM). The results of the SEM image analysis confirmed that the morphology of PA66 nanofibers was not altered by electron beam. The amount of TAC in PA66 nanofiber with TAC was identified by $^1H-NMR$ analysis. The degradation temperature of PA66 nanofibers with TAC at an absorbed dose of 20~100 kGy was higher than the irradiated PA66 nanofiber without TAC. On the other hand, the decreasing rate of modulus of irradiated PA66 nanofibers with TAC was less than PA66 nanofibers.

• YAKHAK HOEJI
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• v.29 no.2
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• pp.76-89
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• 1985

The effects of ginseng saponin on the activity, phosphorylation, [$^{3}$H] ouabain binding and light scattering (disruption) of purified $Na^{+}$ ,$K^{+}$ -ATPase isolated from the outer medulla of sheep kidney were compared to those of gypsophila saponin, sodium dodecylsulfate (SDS), and Triton X-100 on the same parameters. $Na^{+}$ , $K^{+}$ -ATPase activity, phosphorylation, and [$^{3}H$] ouabain binding were inhibited by ginseng saponin (triol>total>diol), SDS, or Triton X-100, but increased by gypsophila saponin. Low doses of ginseng saponin (3.mu.g saponin/.mu.g protein) decreased phosphorylation sites and ouabain binding site concentration (Bmax) without any change of turnover number and affinity for ouabain binding which were decreased by high dose of ginseng saponin (over 10.mu.g saponin/.mu.g protein), SDS or Triton X-100. On the other hand, gypsophila saponin increased the affinity without any change of Bmax for ouabain binding. Inhibition of $Na^{+}$ ,$K^{+}$ -ATPase activity by ginseng saponin and SDS or Triton X-100 appeared before and after decrease in light scattering, respectively. These data suggest that ginseng saponins (total, diol, triol saponin) inhibit $Na^{+}$ , $K^{+}$ -ATPase activity by specific direct and general detergent action at low and high concentrations, respectively, and this inhibitory action of ginseng sapornin to $Na^{+}$ , $K^{+}$ -ATPase is not general action of all saponins.

• Archives of Pharmacal Research
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• v.27 no.1
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• pp.94-98
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• 2004

Effects of dopaminergic drugs on the degranulation of mast cells (RBL-2H3 cells) and the nitric oxide production from macrophage cells (RAW 264.7) were studied. Among the dopaminergic agonists and antagonists tested, bromocriptine, 7-OH-DPAT, haloperidol, and clozapine showed potent inhibitions of mast cell degranualtion ($IC_{50} value, 5 \mu$ M). However, these dopaminergic agents did not affect the tyrosine phosphorylations of the signaling components of the high affinity IgE receptor ($Fc\varepsilonRI$), such as Syk, $PLC\gamma1$, and $PLC\gamma2$.; This suggested that these signaling components were not involved in the inhibition of the mast cell degranulation by these compounds. On the other hand, dopamine, bromocriptine, 7-OH-DAPT, and haloperidol markedly inhibited the nitric oxide production from RAW 264.7 cells ($IC_{50}$ values, 10-20$\mu$M). Bromocriptine, a dopamine agonist that is routinely used for the treatment of Parkinsons disease, inhibited the expression of the inducible nitric oxide synthase at an early stage of the LPS-induced protein expression in a dose-dependent manner. The results suggested that these dopaminergic agents, when used for the treatment of dopamine receptors-related diseases, such as Schizophrenia or Parkinsons disease, might have additional beneficial effects.

• Biomedical Science Letters
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• v.25 no.2
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• pp.123-130
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• 2019

Platelet aggregation is essential for hemostatic process in case of blood vessels damages. However, excessive platelet aggregation can cause cardiovascular disorders including atherosclerosis, thrombosis and myocardial infarction. Scopoletin is usually found in the roots of genus Scopolia or Artemisia, and is known to have anticoagulant and anti-malarial effects. This study investigated the effect of scopoletin on human platelet aggregation induced by U46619, an analogue of thromboxane $A_2(TXA_2)$. Scopoletin had anti-platelet effects by down-regulating $TXA_2$ and intracellular $Ca^{2+}$ mobilization ($[Ca^{2+}]_i$), the aggregation-inducing molecules generated in activated platelets. On the other hand, scopoletin increased the levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), which are known to be intracellular $Ca^{2+}$ antagonists. This resulted in inhibition of fibrinogen binding to ${\alpha}IIb/{\beta}_3$ in U46619-induced human platelet aggregation. In addition, scopoletin inhibited the release of adenosine trisphosphate (ATP) in dose-dependent manner. This result means that the aggregation amplification activity through the granule secretion in platelets was suppressed by scopoletin. Therefore, we demonstrated that scopoletin has a potent antiplatelet effect and is highly likely to prevent platelet-derived vascular disease.

• Journal of The Korean Society of Clinical Toxicology
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• v.16 no.2
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• pp.172-175
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• 2018

Acute nicotine poisoning by liquid nicotine for electronic cigarettes is becoming an increasing problem worldwide. On the other hand, there are no regulations regarding its concentration, container or labelling in Korea. This is the first case of a cardiac arrest after liquid nicotine ingestion that was confirmed by plasma nicotine detection in Korea. A 34-year-old male was found with a cardiac arrest at home by the emergency medical services crew, and had a return of spontaneous circulation after 27 minutes of cardio-pulmonary resuscitation. The cause of his cardiac arrest was suspected to be acute nicotine poisoning by the ingestion of liquid nicotine. Toxicology analysis of the National Forensic Service confirmed plasma nicotine, and the pharmacokinetic estimated average concentration of plasma nicotine at the time of the cardiac arrest was 29.7 mg/L, a lethal dose. He was hospitalized for further treatment, but was discharged after 20 days without any improvement. Considering the strong toxicity of nicotine, appropriate policy decisions are required for sales and distribution.