• Transactions of Materials Processing
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• v.13 no.1
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• pp.59-64
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• 2004

Nano-scratch tests were performed on PMMA thin films spin-coated on a Si substrate using an atomic force microscopy (AFM) with loads ranging form 10nN to 100nN. At low loads, a ridge pattern was formed on the PMMA thin film surface. No wear particles were observed during the pattern-forming mild wear. At high loads, severe wear by plowing occurred, accompanied by wear particles. The film with the highest hardness showed the highest wear resistance. Friction force generated during the scratching was measured, which was closely related with surface deformation of the film. A simple empirical equation to deduce scratch hardness of the film from a linear fixed-distance scratch test was proposed, and scratching-speed dependency of the scratch hardness was displayed.

• Journal of Life Science
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• v.24 no.4
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• pp.447-453
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• 2014

In this study, a test for the immunity control effect by ethanolic extract of Eurya emarginata (EE-70E) on NC/Nga mice as the models for atopic dermatitis was conducted with the following results. Atopic dermatitis in NC/Nga mice was induced by repeated application of 1-chloro-2,4-dinitrobenzene (DNCB) for 5 weeks. Mice were orally administered EE-70E or terfenadine, positive control for 3 weeks. Scratching behavior, clinical skin severity, and the levels of IL-4, L-13, IL-17, total serum IgG1, and total serum IgE were measured. The oral administration with EE-70E doses of 200 or 400 mg/kg significantly decreased scratching behavior scores and clinical skin severity score in a dose-dependent manner (p<0.05). The administration of EE-70E at 400 mg/kg significantly decreased cytokines within the blood serum, that is, IL-4, L-13, and IL-17 compared to the control group (p<0.05). The level of blood histamine was statistically significantly decreased. Administration of EE-70E at 400 mg/kg significantly decreased the levels of total serum IgE (p<0.05). The above results indicated that EE-70E was effective in improving the symptoms of atopic dermatitis through various immunity control mechanisms.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.3
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• pp.10-19
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• 2008

Objective : To investigate the effects of Radix Ophiopogon japonieus on atopic dermatitis, I prepared DNCB(2,4-dinitrochlorobenzen) induced atopic dermatitis NC/Nga mice and observed the mice by four ways; eye observation, the number of skin behavior times, histological changes of skin and cytokine(Total IgE, IL-4, $IFN-{\gamma}$). Methods : After prepare Radix Ophiopogon japonicus extract, DNCB induced atopic dermatitis NC/Nga mice were divided into three groups. The first is Control group which was intact group. The second is Medication group which was orally medicated Radix Ophiopogon japonicus extract one time a day for consecutive 5 days. The third group is Application group which was applied Radix Ophiopogon japonicus extract externally one time a day for consecutive 5 days. After that, the effect of Radix Ophiopogon japonicus on atopic dermatitis was observed. Statistical analysis was performed by using Kmskal-Wallis test and statistical significance was set at less than 5%. Results : 1. Radix Ophiopogon japonicus showed some in both Medication group and Application At observation of skin morphologic change, effects to prevent erythema reaction on skin group. 2. At the number of scratching behavior times, Radix Ophiopogon japonicus showed an effect to decrease scratching behavior times, but there was no statistical significance among three groups. 3. At skin tissue H-E stain, Radix Ophiopogon japonicus showed an effect to prevent skin epidermal tissue damages and also showed that it could keep the skin healthy in both Medication group and Application group. Especially in Application group, the skin of mouse showed almost normal recovery. 4. At cytokines, there was no statistical significance among three groups in IgE and IL-4. But Radix Ophiopogon japonicus showed an significant effect to suppress $IFN-{\gamma}$ in both Medication group and Application group. There was no significant difference between two groups. Conclusion : Radix Ophiopogon japonicus has some effects on atopic dermatitis in both internal medication and external application.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.3
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• pp.249-257
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• 2007

State of problem : The use of zirconium oxide all-ceramic material provides several advantages, including a high flexural strength(>1000MPa) and desirable optical properties, such as shading adaptation to the basic shades and a reduction in the layer thickness. Along with the strength of the materials, the cementation technique is also important to the clinical success of a restoration. Nevertheless, little information is available on the effect of different surface treatments on the bonding of zirconium high-crystalline ceramics and resin luting agents. Purpose : The aim of this study was to test the effects of surface treatments of zirconium on shear bond strengths between bovine teeth and a zirconia ceramic and evaluate differences among cements Material and methods : 54 sound bovine teeth extracted within a 1 months, were used. They were frozen in distilled water. These were rinsed by tap water to confirm that no granulation tissues have left. These were kept refrigerated at $4^{\circ}C$ until tested. Each tooth was placed horizontally at a plastic cylinder (diameter 20mm), and embedded in epoxy resin. Teeth were sectioned with diamond burs to expose dentin and grinded with #600 silicon carbide paper. To make sure there was no enamel left, each was observed under an optical microscope. 54 prefabricated zirconium oxide ceramic copings(Lava, 3M ESPE, USA) were assigned into 3 groups ; control, airborne-abraded with $110{\mu}m$ $Al_2O_3$ and scratched with diamond burs at 4 directions. They were cemented with a seating force of 10 ㎏ per tooth, using resin luting cement(Panavia $F^{(R)}$), resin cement(Superbond $C&B^{(R)}$), and resin modified GI cement(Rely X $Luting^{(R)}$). Those were thermocycled at $5^{\circ}C$ and $55^{\circ}C$ for 5000 cycles with a 30 second dwell time, and then shear bond strength was determined in a universal test machine(Model 4200, Instron Co., Canton, USA). The crosshead speed was 1 mm/min. The result was analyzed with one-way analysis of variance(ANOVA) and the Tukey test at a significance level of P<0.05. Results : Superbond $C&B^{(R)}$ at scratching with diamond burs showed the highest shear bond strength than others (p<.05). For Panavia $F^{(R)}$, groups of scratching and sandblasting showed significantly higher shear bond strength than control group(p<.05). For Rely X $Luting^{(R)}$, only between scratching & control group, significantly different shear bond strength was observed(p<.05). Conclusion : Within the limitation of this study, Superbond $C&B^{(R)}$ showed clinically acceptable shear bond between bovine teeth & zirconia ceramics regardless of surface treatments. For the surface treatment, scratching increased shear bond strength. Increase of shear bond strength by sandblasting with $110{\mu}m$ $Al_2O_3$ was not statistically different.

• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.150-157
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• 1997

Capsaicin cream has been used to attenuate the pain associated with diabetic neuropathy, rheum-atoid arthritis, osteoarthritis and postherpetic neuralgia. But its common side effect, local irritation, limits the use of it and there is still a need for a new analgesic devoid of this side effect. This study was conducted to compare the local irritant effect of DA-5018, a new capsaicin derivative, with that of capsaicin in various animal models and human beings. Capsaicin, applied topically to the mouse ear, produced dose-dependent increase of ear volume and the frequency of ear scratching behavior in mice. Neither ear volume nor scratching behavior was affected by DA-5018. In eye wiping test of rat, DA-5018 was 10 times less irritant than capsaicin. Capsaicin administered intradermally into the rat paw elicited paw lick/lift response with a potency which was three times that of DA-5018. Zostrix-HP (0.075% capsaicin cream), but not DA-50180.3% cream, increased ear volume of rat and induced thermal hyperalgesia in normal and carrageenan inflamed paws. Six day-treatment of Zostrix-HP failed to develop tolerance against this thermal hyperalgesia. In human beings, Zostrix-HP produced burning sensation and itching in more than 90% of volunteers involved and its maximum irritant effect was significantly higher than that of DA-5018 cream. These results suggest that local irritation and burning sensation produced by DA-5018 is much less than capsaicin.

• Transactions of Materials Processing
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• v.22 no.2
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• pp.86-92
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• 2013

When stamping ultra-high-strength steel (UHSS), the phenomenon of galling, which corresponds to a transfer of material from the sheet to the tool surface, occurs because of the high contact pressure between tool and workpiece. Galling leads to increased friction, unstable interface conditions, scratches on the sheet and the tool surfaces and, eventually, premature tool surface failures. Therefore, a simple and accurate evaluation method for tool scratching is necessary for the selection of tool material and coating, as well as for a better optimization of process conditions such as blank holder force and die radius. In this study, the pin-on-disc (PODT) and pin-on-flat surface (POFST) tests are conducted to quantitatively evaluate scratch-related tool life for stamping of UHSS. The variation of the friction coefficient is used as an indicator of scratch resulted from galling. The U-channel ironing test (UCIT) is performed in order to validate the results of the friction tests. This study shows that the POFST test provides a good quantitative estimation of tool life based on the occurrence of scratch.

• Journal of Ginseng Research
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• v.39 no.3
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• pp.257-264
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• 2015

Background: Korean Red Ginseng-a steamed root of Panax ginseng Meyer-has long been used as a traditional medicine in Asian countries. Its antipruritic effect was recently found, but no molecular mechanisms were revealed. Thus, the current study focused on determining the underlying molecular mechanism of Korean Red Ginseng extract (RGE) against histamine-induced itch at the peripheral sensory neuronal level. Methods: To examine the antipruritic effect of RGE, we performed in vivo scratching behavior test in mice, as well as in vitro calcium imaging and whole-cell patch clamp experiments to elucidate underlying molecular mechanisms. Results: The results of our in vivo study confirmed that RGE indeed has an antipruritic effect on histamine-induced scratching in mice. In addition, RGE showed a significant inhibitory effect on histamine-induced responses in primary cultures of mouse dorsal root ganglia, suggesting that RGE has a direct inhibitory effect on sensory neuronal level. Results of further experiments showed that RGE inhibits histamine-induced responses on cells expressing both histamine receptor subtype 1 and TRPV1 ion channel, indicating that RGE blocks the histamine receptor type 1/TRPV1 pathway in sensory neurons, which is responsible for histamine-dependent itch sensation. Conclusion: The current study found for the first time that RGE effectively blocks histamine-induced itch in peripheral sensory neurons. We believe that the current results will provide an insight on itch transmission and will be helpful in understanding how RGE exerts its antipruritic effects.

• International Journal of Oral Biology
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• v.36 no.2
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• pp.43-50
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• 2011

Voltage dependent calcium channel (VDCC), one of the most important regulator of $Ca^{2+}$ concentration in neuron, play an essential role in the central processing of nociceptive information. The present study investigated the antinociceptive effects of L, T or N type VDCC blockers on the formalin-induced orofacial inflammatory pain. Experiments were carried out on adult male Sprague-Dawley rats weighing 220-280 g. Anesthetized rats were individually fixed on a stereotaxic frame and a polyethylene (PE) tube was implanted for intracisternal injection. After 72 hours, 5% formalin ($50 \;{\mu}L$) was applied subcutaneously to the vibrissa pad and nociceptive scratching behavior was recorded for nine successive 5 min intervals. VDCC blockers were administered intracisternally 20 minutes prior to subcutaneous injection of formalin into the orofacial area. The intracisternal administration of 350 or $700{\mu}g$ of verapamil, a blocker of L type VDCC, significantly decreased the number of scratches and duration in the behavioral responses produced by formalin injection. Intracisternal administration of 75 or $150 \;{\mu}g$ of mibefradil, a T type VDCC blocker, or 11 or $22\; {\mu}g$ of cilnidipine, a N type VDCC blocker, also produced significant suppression of the number of scratches and duration of scratching in the first and second phase. Neither intracisternal administration of all VDCC blockers nor vehicle did not affect in motor dysfunction. The present results suggest that central VDCCs play an important role in orofacial nociceptive transmission and a targeted inhibition of the VDCCs is a potentially important treatment approach for inflammatory pain originating in the orofacial area.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.471-474
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• 2005

This study investigates the nano/microstructure, the aging response, and the mechanical/tribological properties of the eutectic regions in rheoformed A356 alloy-T5 parts using nano/micro-indentation and mechanical scratching, combined with optical microscopy and atomic force microscope (AFM). Most eutectic Si crystals in the A356 alloy showed a modified morphology as fine-fibers. The loading curve for the eutectic region was more irregular than that of the primary Al region due to the presence of various particles of varying strength. The aging responses of the eutectic regions in the rheoformed A356 alloys aged at $150^{\circ}C$ for different times (0, 2, 4, 8, 10, 16, 24, 36, and 72 h) were investigated. Both Victors hardness $(H_v)$ and indentation $(H_{IT})$ test results showed a similar trend of aging curves, and the peak was obtained at the same aging time of 10 h. A remarkable size-dependence of the tests was found.

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.691-694
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• 1996

Two models of scratch testers developed recently are applied to the adhesion measurement of thin coatings. In both models the critical load is determined from the frictional irregularity when coated surface is broken in the scratching process. One model is effective for coatings thicker than 1m and the other for thin coatings down to $0.1\mu\textrm{m}$. The mechanism and the measurement principle of these testers are described. High sensitivity and good reproducibility of the measurement are attained primarily by the employment of new detection devices. These testers are even more useful for the quality control and the inspection of commercial products of coatings because only a small area of specimen is required for the test.