• The Korean Journal of Pain
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• v.14 no.1
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• pp.1-6
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• 2001

Background: Subcutaneous injection of 5% formalin into the hind paw of the rat produces a biphasic nociceptive response. The second phase depends on changes in the dorsal horn cell function that occur shortly after an initial C-fiber discharge, spinal sensitization, or windup phenomenon. This study was performed to investigate the role of glutamate during spinal sensitization. Methods: Sprague-Dawley rats weighing 200 to 250 g were used for this study. Under light anesthesia (0.5% isoflurane) the rats were segregated in a specially designed cage and $50{\mu}l$ 0.5% formalin was injected subcutaneously in the foot dorsum of right hindlimb. Forty minutes after the formalin injection, the rat was quickly decapitated and spinal cord was removed. The spinal segments at the level of L3 (largest area) was collected and stored in a deep freezer ($-70^{\circ}C$). The mRNA gene expression of N-methyl-D-aspartate receptor (NMDAR) and the metabotropic glutamate receptor subtype 5 (mGluR5) were determined by the polymerase chain reaction. Results: The number of flinches was $19.8{\pm}2.3/min$. at one minute after formalin injection and decreased to zero after then. The second peak appeared at 35 and 40 minutes after formalin injection. The values were $17.8{\pm}2.2$ and $17.2{\pm}3.0/min$. The mRNA gene expressions of NMDAR and mGluR5 were increased by $459.0{\pm}46.8%$ (P < 0.01) and $111.1{\pm}4.8%$ (P > 0.05) respectively at 40 minutes after formalin injection. The increased rate of NMDAR was significantly higher than that of mGluR5 (P < 0.01). Conclusions: From these results it suggested that NMDAR partly contributed to the mechanism of central sensitization after the formalin test but mGluR5 did not.

• Journal of Environmental Health Sciences
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• v.46 no.6
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• pp.685-693
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• 2020

Objectives: Recent data indicate that sensitization to mold contributes to the severity and persistence of asthma. The aim of this study was to investigate relationships between indoor mold concentrations and pulmonary function parameters in asthmatic children with mold sensitization. Methods: Asthmatic subjects who had a positive result in skin-prick testing to more than one mold allergen, such as Alternaria, Aspergillus, or Penicillium, were enrolled. Their pulmonary function and methacholine challenge test results were collected. Measurements of blood eosinophil, serum IgE, and fractional exhaled nitric oxide (FeNO) were taken. Indoor levels of VOC, CO2, PM10 and PM2.5 in each subject's house were measured. We counted mold and bacteria colonies from the subjects' house air samples. Results: The mean levels of FEV1, FVC, FEV1/FVC, and FEF25-75 were 82.8±19.7, 87.3±17.9, 85.8±8.3, and 82.3±28.9%, respectively. The mean FeNO level was 19.8±11.2 ppb and the geometric mean (range of one SD) of methacholine PC20 was 3.99 mg/mL (0.67-23.74 mg/mL). The average indoor air pollutant levels were below the recommended levels set by the Ministry of Environment for multiplex buildings. Indoor mold levels showed a significant inverse correlation with methacholine PC20, but not with the baseline pulmonary function parameters. Conclusion: Indoor mold concentrations are a risk factor for increased bronchial hyperresponsiveness among asthmatic children with mold sensitization. Targeted environmental intervention should be considered for selected asthmatic children with mold sensitization for avoiding severe airway hyperresponsiveness.

• Journal of Oral Medicine and Pain
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• v.41 no.4
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• pp.195-199
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• 2016

Central sensitization represents a functional change of second order neuron induced by continuous deep pain input and maintained by psychosocial factors. When afferent neurons are involved with central sensitization, secondary hyperalgesia can appear. Secondary hyperalgesia is an increased sensitivity to stimulation without a local cause. Reports on secondary hyperalgesia to heat stimuli are relatively rare compared to mechanical stimuli. And there were few reports of secondary hyperalgesia to heat stimuli in the oral cavity. We presented a case of secondary hyperalgesia to heat stimuli in the gingival area induced by continuous odontogenic pain with a review of the related literature.

• Journal of the Korean Society of Safety
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• v.25 no.6
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• pp.28-33
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• 2010

Stainless steel is useful material for various industrial facilities such as the nuclear and steam power plant and the heavy chemical industry due to its good corrosion resistance and mechanical properties. However, it has also a large problem that is sensitized in the welding process and its corrosion resistance and mechanical properties decreases by sensitization. Thus, corrosion and corrosion fatigue characteristics of artificially sensitized austenitic STS304 were investigated through the EPR test and corrosion fatigue test. Obtained results are as follows: 1) According to the sensitizing period increase, Cr deficiency layer is linearly expanded. 2) Degree of sensitization(Ia/Ir) proportionally increased with sensitizing period. However, after 4hrs, it showed constant value. 3) Cr-carbide($Cr_{23}C_6$) in the grain boundary increased as sensitizing period increases until six hours. 4) corrosion fatigue strength of sensitized STS304 were remarkably reduced compare to non-sensitized ones.

• Corrosion Science and Technology
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• v.9 no.6
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• pp.300-309
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• 2010

The influences of sensitization on localized corrosion resistance of 304 stainless steel, were investigated, using micro-dropletcell techniques. Micro-droplet cell allows one to align the micro-electrode to the desired spot of the working electrode and measure directly local current with the potentiodynamic polarization, linear polarization and a.c. impedance. Micro-electrochemical tests were carried out inside of the grain and on grain boundaries separately. It was found that sensitization decreased the pitting potential, increasing corrosion current density around grain boundaries. Galvanic current density was also measured between grain and grain boundaries.

• Journal of the Korean Applied Science and Technology
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• v.18 no.2
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• pp.136-141
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• 2001

Naphthothiazolo carbocyanine is of industrial importance as red-sensitizing dye in the spectral sensitization of emulsion microcrystals in negative film-making. In this study, red-sensitizing dye was prepared by the reaction of 2-methyl-3-sulfopropyl-4,5-naphthothiazolium(inner salt) with triethyl orthoacetate in the presence of triethylamine. The product was identified by using various analytical tools such as Elemental analyzer, IR spectrophotometer, UV-Vis spectrophotometer, Mass spectrometer, $^{1}H-NMR$ spectrometer, TGA and DSC. The maximum absorption peak in methanol solvent was 573nm. Therefore, it was concluded that naphthothiazolo carbocyanine dye can be used as red0sensitizing dye for the spectral sensitization of photographic emulsion.

• Journal of the Korean Applied Science and Technology
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• v.25 no.2
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• pp.226-231
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• 2008

In this study, benzoxazolo carbocyanine is of industrial importance as green-sensitizing dye in the spectral sensitization. Sensitizing dye was prepared by the reaction of 2-methyl-3-sulfopropyl-4,5-benzoxazolium (inner salt) with triethyl orthobenzoate in the presence of triethylamine. The product was identified by using various analytical tools such as elemental analyzer, IR spectrophotometer, UV-Vis spectrophotometer, $^1H$-NMR spectrometer, TGA and DSC. The maximum absorption peak in methanol solvent was 507 nm. Therefore, it was concluded that benzoxazolo carbocyanine dye can be used as sensitizing dye for the spectral sensitization of photographic emulsion and color cosmetics.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.416-421
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• 2014

Naphthothiazolo carbocyanine is of industrial importance as red-sensitizing dye in the spectral sensitization. Sensitizing dye was prepared by the reaction of 2-methyl-3-sulfopropyl-4,5-naphthothiazolium (inner salt) with triethyl orthopropionate in the presence of triethylamine. The product was identified by using various analytical tools such as elemental analyzer, IR spectrophotometer, UV-Vis spectrophotometer, $^1H$-NMR spectrometer, TGA and DSC. The maximum absorption peak in methanol solvent was 578nm. Therefore, it was concluded that naphthothiazolo carbocyanine dye can be used as sensitizing dye for the spectral sensitization of photographic emulsion and color cosmetics.

• Biomolecules & Therapeutics
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• v.27 no.4
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• pp.357-362
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• 2019

Limonene is a cyclic terpene found in citrus essential oils and inhibits methamphetamine- induced locomotor activity. Drug dependence is a severe neuropsychiatric condition that depends in part on changes in neurotransmission and neuroadaptation, induced by exposure to recreational drugs such as morphine and methamphetamine. In this study, we investigated the effects of limonene on the psychological dependence induced by drug abuse. The development of sensitization, dopamine receptor supersensitivity, and conditioned place preferences in rats was measured following administration of limonene (10 or 20 mg/kg) and methamphetamine (1 mg/kg) for 4 days. Limonene inhibits methamphetamine- induced sensitization to locomotor activity. Expression of dopamine receptor supersensitivity induced by apomorphine, a dopamine receptor agonist, was significantly reduced in limonenepretreated rats. However, there was no significant difference in methamphetamine-induced conditioned place preferences between the limonene and control groups. These results suggest that limonene may ameliorate drug addiction-related behaviors by regulating postsynaptic dopamine receptor supersensitivity.

• Biomolecules & Therapeutics
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• v.31 no.4
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• pp.388-394
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• 2023

Nitric oxide (NO) is a signaling molecule that plays a crucial role in numerous cellular physiological processes. In the skin, NO is produced by keratinocytes, fibroblasts, endothelial cells, and immune cells and is involved in skin functions such as vasodilation, pigmentation, hair growth, wound healing, and immune responses. NO modulates both innate and adaptive immune responses. As a signaling molecule and cytotoxic effector, NO influences the function of immune cells and production of cytokines. NO is a key mediator that protects against or contributes to skin inflammation. Moreover, NO has been implicated in skin sensitization, a process underlying contact dermatitis. It modulates the function of dendritic cells and T cells, thereby affecting the immune response to allergens. NO also plays a role in contact dermatitis by inducing inflammation and tissue damage. NO-related chemicals, such as nitrofatty acids and nitric oxide synthase (NOS) inhibitors, have potential therapeutic applications in skin conditions, including allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD). Further research is required to fully elucidate the therapeutic potential of NO-related chemicals and develop personalized treatment strategies for skin conditions.