• Korean Journal of Food Science and Technology
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• v.40 no.4
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• pp.436-442
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• 2008

Hydroxyproline and Pro-Hyp dipeptide are the digestive products of collagen hydrolysate called collagen peptide. Some suggested that collagen peptides could improve aged or damaged skins, however, the effects of collagen peptides on the skin have not been known. In this study, we investigated the effects of digestive products of collagen peptides, hydroxyproline and Pro-Hyp dipeptide on skin quality using the UV-damaged dorsal skin of hairless mouse as a model system. Female SKH hairless mice were pre-irradiated with UV for 7 weeks, and then hydroxyproline, Pro-Hyp dipeptide were orally administered for 7 weeks with UV irradiation. Wrinkle formation (by replica image), skin elasticity, barrier status (by TEWL, transepidermal water loss), epidermis thickness, and biophysical changes in the stratum comeum (by hematoxylin & eosin staining) were examined. With the oral peptide treatment, effects such as skin barrier maintenance, anti-skin thickening, and recovery of the stratum corneum were observed. These results indicate that oral intake of collagen peptides may have beneficial effects on damaged skin cells.

• Membrane Journal
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• v.25 no.6
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• pp.530-537
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• 2015

Photovoltaic (PV) modules are environmentally energy conversion devices to generate electricity via photovoltaic effect of semiconductors from solar energy. One of key elements in PV modules is "Backsheet," a multilayered barrier film, which determines their lifetime and energy conversion efficiency. The representative Backsheet is composed of chemically resistant poly(vinyl fluoride) (PVF) and cheap poly(ethylene terephthalate) (PET) films used as core and skin materials, respectively. PVF film is too expensive to satisfy the market requirements to Backsheet materials with production cost as low as possible. The promising alternatives to PVF-based Backsheet are hydrocarbon Backsheets employing semi-crystalline PET films instead of PVF film. It is, however, necessary to provide improved barrier property to water vapor to the PET films, since PET films are suffering from hydrolytic decomposition. In this study, a polyurethane adhesive with reduced water vapor permeation behavior is developed via a homogeneous distribution of hydrophobic silica nanoparticles. The modified adhesive is expected to retard the hydrolysis of PET films located in the core and inner skin. To clarify the efficacy of the proposed concept, the mechanical properties and electrochemical PV performances of the Backsheet are compared with those of a Backsheet employing the polyurethane adhesive without the silica nanoparticles, after the exposure under standard temperature and humidity conditions.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.260-260
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• 2014

Dermatophytes can invade in keratinized tissues and cause dermatophytosis [1] that rank among the most widespread and common infectious diseases world-wide. Although several systemically and topically administered drugs with activities against these fungi are available, still complete eradication of some of these infections, is difficult and relapses and remissions are often observed [2,3]. In addition, some people are allergic to many of the available drugs which add complications even more. Therefore, the search for novel, selective and more effective therapy is always required and it may help the clinicians to choose the correct treatment for their patients. Non-thermal plasmas primarily generate reactive species and recently have emerged as an efficient tool for medical applications including sterilization. In this study, we evaluated the ability of non-thermal dielectric barrier discharge (DBD) plasma for the inactivation of clinical isolates of Trichophyton genera, Trichophyton mentagrophytes (T. mentagrophytes) and Trichophyton rubrum (T. rubrum), which cause infections of nails and skin and, are two of the most frequently isolated dermatophytes [4]. Our results showed that DBD plasma has considerable time dependent inactivation potential on both T. mentagrophytes and T. rubrum in-vitro. Furthermore, the mechanisms for plasma based T. mentagrophytes and T. rubrum inactivation and planning for in-vivo future studies will be discussed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.17 no.1
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• pp.64-80
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• 1991

The SKINTEX Method is based on a two-compartment physico-chemical model which includes a Biomembrane Barrier in compartment one and an organized macromolecular matrix in compartment two. Test samples absorb onto or permeate through the keratin/collagen Biomembrane Barrier and then can interact with the organized macromolecular matrix. Changes in the integrity of the barrier release a dye indicator: Changes in the matrix can alter its transparency. The sum of these two responses is read spectrophotometrically at 470nm. An early investigation of 950 chemicals and formulations in the SKINTEX System produced results which were 89% concordance to in vivo Draize dermal irritation results obtained with 24-hour occluded application of test samples with-out abrasion and standard scoring. Alkaline materials were analyzed in a specialized SKINTEX AMA Protocol. In this early study, the model did not distinguish nonirritant test materials and formulation with PDII(Primary Dermal Irritation Index)in the range from 0 to 1.2, A High Sensitivity Assay Protocol(HSA)was developed to amplify the changes in both compartments of this model and provide more accurate calibration of these changes. A study of 60 low irritation test samples including cosmetics, household products, chemicals and petro-chemicals distinguished nonirritants with PDII $\leq$ 0.7 for 26 of 30 nonirritants. A second protocol was developed to evaluate the SKINTEX model predictability with respect to human irritation. The Human Response Assay (HRA )has been optimized based on differences in penetration and irritation responses in humans and rabbits. An additional 32 test materials with different mechanisms and degrees of dermal toxicity were evaluated by the HRA. These in vitro results were 86% concordant to human patch test results. In order to further evaluate this model, a Standard Chemical Labelling (SCL) Protocol was developed to optimize this system to predict Draize dermal irritation results after a 4-hour application of the test material. In a study of 52 chemicals including acids, bases, solvents, salts, surfactants and preservatives, the SCL results demonstrated 85% concordance to Draize results for a 4-hour application of test samples on non-abraded rabbit skin. The SKINTEX System, including three specialized protocols, provided results which demonstrated good correlation to the endpoint of dermal irritation in man and rabbits at different application times.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.4
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• pp.413-420
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• 2016

Hydroxy acid has been used to enhance anti-aging and skin moisturization by peeling effect on the skin stratum corneum, and thus it has been widely used in topical products and cosmetic products. Among them, the effect that appears most effectively in a short period of time has been reported to be effected by the pH of the cosmetic formulations. However, there are many difficulties in use due to irritation caused by pH and concerns about side effects. The purpose of this study was to evaluate the effect of applying cosmetics with (1) varying concentrations, (2) types and (3) pH of hydroxy acid on human skin. 22 healthy adults were stained with DHA (dihydroxyacetone) and DC (dansyl chloride) on the forearm, and the skin exfoliation effect was measured after application of the test products. (1) The application of GA (glycolic acid) increased the desquamation by concentration dependent. (2) the test product prepared with neutral pH showed no exfoliation effect. In contrast, SA (salicylic acid) showed a statistically significant exfoliation effect at both acidic pH and neutral pH. (3) The neutral pH SA showed excellent exfoliation effect on bot DHA and DC stained stratum corneum. These results suggest that it is possible to manufacture safe cosmetics without damaging the skin barrier, providing an opportunity to use cosmetics that are expected to exfoliate to people, whose skin is sensitive to pH.

• Archives of Pharmacal Research
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• v.24 no.3
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• pp.224-228
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• 2001

DA-5018, a recently synthesized capsaicin analog, appears to possess potent analgesic activity when administered topically. The objective of this study is to test the feasibility of the topical administration of this compound. Specifically, our goal was to identify vehicle system that permit a reasonable transdermal permeation of the compound in mice. Among the vehicles examined, isopropyl myristate (IPM) showed the largest in vitro permeability across the intact skin (83.6 ${\pm}$ 5.42${\mu}$l/$\textrm{cm}^2$/h ). However, due to the limited solubility of DA-5018 in IPM (0.53 mg/ml), the maximal flux from the IPM medium remained at only 44.3 ${\pm}2.87{\mu}$g/$\textrm{cm}^2$/hr. In order to increase the flux, addition of better solvents for DA-5018 was attempted, under the assumption that flux is the result of both solubility and permeability. Ethoxydiglycol (EG) and oleic acid (OA) were selected as examples of food solvents. The addition of IC or OA to IPM at a 1:1 volume ratio resulted in a comparable increase in the solubility of the compound (i.e., to 61.1 and 50.2 mg/ml for EG and OA, respectively). However, the addition of EG at a 1:1 volume ratio, for example, increased the flux 6.3 fold (i.e., $279{\mu}$g/$\textrm{cm}^2$/hr), while OA, at a 1:1 volume ratio, decreased the flux 5 fold (i.e., $9.26{\mu}$g/$\textrm{cm}^2$//hr). The mechanism of this discrepancy between EG and OA was investigated by measuring the permeabilty of DA-5018 across the stratum corneum-removed skin of the mouse, under the hypothesis that the viable skin layer may serve as a barrier for the permeation of lipophilic substances such as DA 5018. The permeability of DA-5018, from the medium of EG or OA, across the viable skin differed greatly for EG ($0.41{\mu}$l/$\textrm{cm}^2$/hr) and OA ($0.086{\mu}$l/$\textrm{cm}^2$/hr), suggesting that a higher permeability across the viable skin layer is needed for the second solvents. The maximum flux across the intact skin was achieved for DA-5018 when EG was added to IPM at a 1:1 volume ratio. Thus, the use of a binary system appears to be the best approach for realizing the transdermal delivery of DA-5018 at a reasonable rate.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.345-352
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• 2004

There are two paradigms to explain the atopic dermatitis. The first is outside-inside paradigm and the second is inside-outside paradigm. According to the outside-inside paradigm the best way to treat the atopic dermatitis is recovery of skin barrier function. The barrier function is maintained by the specific structure of stratum corneum, which is constructed from corneocytes and intercellular lipids. In terms of lipid structures of SC in atopic dermatitis and lamellar ichthyosis, they contain more fluid hexagonal gel structures in SC and show deficiencies in free fatty acids, especially long chains and certain ceramides. With this reason, moisturizer which has the lamellar structure and restoring function of intrinsic intercellualr long periodicity phase can maintain and restore the lamellar structure of intercellular lipids in SC. The moisturizers containing ceramide or pseudoceramide also seem to be reasonable therapy for atopic dermatitis and several skin diseases, which interrelated with impaired skin harrier. By the way, according to the inside-outside paradigm, immune response including helper T cells, IgE, eosinophils is related. It is effective treatment of atopic dermititis to restore imbalance between Th1 and Th2 cells. Even though several kinds of immune-suppressor were introduced, these can affect the intrinsic immune function. SPC and S1P, metabolites of ceramide, would be interesting because they have the function of wound healing and immune modulating properties.

• Journal of Pharmaceutical Investigation
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• v.36 no.6
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• pp.393-399
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• 2006

This study was aimed to design, formulate and characterize the moisture-activated patches containing acyclovir for antiviral action. Gel intermediates for film-type patches were prepared with mucoadhesive polymer, viscosity builders, enhancers and acyclovir. Patches containing acyclovir were characterized by in vitro measurement of drug release rates through a cellulose barrier membrane, and of drug flux through the hairless mouse skin. Film-type patches obtained were uniform in the thickness and showed a mucoadhesive property when contacted with moisture. The formulation was optimized, which consisted of $Cantrez^{\circledR}$ AN-169(2%), $Kollidon^{\circledR}$ VA 64(1%), $Natrosol^{\circledR}$(1%), hydroxypropyl-$\beta$-cyclodextrin(1%) and dimethylsulfoxide(0.5%). Release rates of acyclovir patches increased dose-dependently. The addition of terpenes such as d-limonene or cineole increased release rates of acyclovir, but decreased permeation rates. The permeation rates were enhanced by 2 and 2.5 times by the addition of glycyrrhizic acid ammonium salt and sodium glycocholate, respectively, compared with that of no enhancer. These results suggest that it may be feasible to deliver acyclovir through the skin or gingival mucosa from the moisture-activated patches.

• Journal of Life Science
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• v.28 no.2
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• pp.141-147
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• 2018

This study aimed to analyze the contents of rutin, procyanidin B3, quercetin, and kaempferol, known to have antioxidant, anti-inflammatory, and anti-carcinogenic effects, among the polyphenol types contained in grape pruning stem extracts (GPSE). It utilized grape stems discarded after harvest to measure the effects of GPSE on skin moisture, inhibition of skin cell proliferation, and anti-inflammatory activity on the damaged skin of HR-1 mice induced with ultraviolet B (UVB), and to verify the applicability of GPSE as a material for functional food and functional cosmetics. The polyphenol was extracted from grape pruning stems with 80% EtOH, and then the extract was used while storing at $-20^{\circ}C$, after filtering, concentrating, and freeze-drying it. The content of an active ingredient of GPSE was analyzed using high performance liquid chromatography (HPLC). From 53 kg of the grape pruning stem specimen, 2.34 kg of the EtOH fraction extracts were extracted to achieve a 4.42% yield ratio. Analysis of the active ingredients showed 0.28 mg/g of procyanidin B3, 12.81 mg/g of rutin, 0.51 mg/g of quercetin, and 8.24 mg/g of kaempferol. After UVB irradiation on the dermis, to confirm the degree of inhibition of collagen synthesis, we examined the protein expression of MMP-9 using immunohistochemical staining. The results of this study confirm the existence of active polyphenol types, such as rutin, kaempferol, quercetin, and procyanidin B3, in GPSE. Moreover, the study found that GPSE has anti-collagenase effects and it decreases the effects of UV damage on skin barrier function. GPSE is a functional ingredient with a potential for skin protection effects, and it has high utilization potential as an ingredient for functional cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.1
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• pp.63-71
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• 2015

Moisturizers are the most prescribed products in dermatology. Treatment with moisturizers aims to maintain skin integrity and overall well-being by providing a healthy appearance. Moisturizers perform very important functions in baby care; however, there are few studies on the effects of moisturizers on the skin of infants. To investigate the effects of moisturizers on the skin of healthy full-term infants and toddlers, thirty-one healthy, full-term, 6- to 36-month-old infants and toddlers without any dermatologic conditions received moisturizer applied to the whole body except the eyes and diaper area after bathing twice daily for 4 weeks. Clinical assessments were conducted before treatment, immediately after the treatment period, and 1 and 4 weeks after treatment. At all visits, skin hydration, transepidermal water loss (TEWL), skin pH, and skin roughness were measured, the skin surface was photographed, and any adverse events were recorded. After using moisturizer, skin hydration significantly increased and TEWL and roughness significantly decreased. The skin pH was modified to mildly acidic and the skin surface was visually smoother than before treatment. There were no statistical significant differences of effects of moisturizers according to age and sex, and adverse events were not observed. The results of moisturizer application on the skin were increased skin hydration, recovery of barrier function, balancing skin pH within a mildly acidic range, and increasing the smoothness of the skin surface for 4 weeks.