Stability and in vivo efficiency of natural cosmetic emulsion systems with the addition of vegetable oils

The aim of the paper is to test stability and biophysical properties of hydrophilic and lipophilic emulsions with selected vegetable seed oils: Limnanthes alba, Prunus amygdalus dulcis, Cannabis sativa, Rosa rubiginosa and Hellianthus annuus. Biophysical properties of emulsions are investigated in vivo using non-invasive instrumental methods (corneometry, tewametry and pH) in a group of 12 healthy women volunteers. Their stability profiles (colour, phase separation and centrifugation) under various temperatures (9, 25, 37 and 57 °C) and storage time (24 hours, 2, 7, 14, 21 and 28 days) were monitored. The moisturising activities of the emulsions supplemented with various oils were comparable. The lipophilic emulsions showed a better ability to improve the condition of the skin barrier due to formation of a surface lipid film. The tested formulations regulated the pH of the skin towards neutral values. Lipophilic emulsions showed earlier phase separation and changes in colour. The greatest resistance to thermal stress during storage was observed for the emulsion bases. Emulsions containing oils, except for those with rosehip and hempseed oils, were stable up to the temperature of 37 °C. The studied emulsion systems are excellent vehicles of vegetable oils and exhibit relatively good stability, benefiting the natural properties of skin.

The Effect of Mometasone Furoate Cream on Skin Barrier Function in Patients with Allergic Contact Dermatitis / 대한피부과학회지

BACKGROUND: It is unclear how the usage of topical steroid agents affects skin barrier function. OBJECTIVE: In order to follow up on previous research into this topic, we sought to investigate the effects of a 3-week application of topical mometasone cream on the alteration of skin barrier function. METHODS: Twenty-six patients who had been clinically diagnosed with allergic contact dermatitis were enrolled. Topical mometasone cream was applied to the skin lesions. Clinical symptoms, transepidermal water loss (TEWL), corneometer unit, and pH value were measured on the initial visit, 1 week after treatment, and 3 weeks after treatment, and their values were compared. RESULTS: Clinical symptoms showed improvement after topical mometasone cream was applied (p0.05). CONCLUSION: This study found that treatment with topical mometasone cream for 3 weeks has no effect on skin barrier function. We believe that this research will help determine the optimal duration and dosage of topical steroid agents used for treating allergic contact dermatitis.

Dermatologic Effects and Management of Urine and Feces on Infant and Adult Skin.

The effect of urine and feces on the skin is a contributing factor to the development of incontinent and diaper dermatitis. The objective of this research was to evaluate skin effects of a given urine or fecal sample on the donor child and/or an adult caregiver, both of whom would be exposed to the biological material in course of daily life. Methods: Urine was evaluated under a variety of experimental skin conditions: normal (N), compromised by tape stripping (C), hydrated by prolonged exposure to water via occlusive patch (H), and hydrated/compromised (H/C). After pre-treatment, sites were patched (3 times of 24-h each) with 0.5 ml infant urine, saline (negative control) or 0.3% sodium lauryl sulfate (SLS, positive control). Fecal material was evaluated using a 4-h patch followed by tape stripping of selected sites. Results: In the urine study, a single 24-h patch produced a significant elevation of pH compared to both the negative (saline) and positive (sodium lauryl sulfate) controls for all experimental skin conditions. Erythema produced by urine was intermediate between the negative and positive controls, and significantly different from the negative control on the N and C skin test sites. All three materials produced an increase in hydration of the skin. The single 4-h patch of fecal material produced significant erythema, a significant elevation of pH, and a significant increase in TEWL. Recovery to pre-treatment levels was observed by the next day on sites that received no further treatment. However, on sites patched with fecal material, then further compromised by tape stripping, recovery to pre-treatment levels for erythema and TEWL were delayed. Conclusion: These studies indicate that urine appears to have an inherent low level irritant property when in continuous contact with skin for 24 to 48 hours. With relatively short exposures of 4 hours fecal material causes visible erythema, increases in pH and TEWL, and decreases in stratum corneum resilience to the subsequent insult of tape stripping. Results re-inforce the utility of modern diapers and incontinent products, utilizing superabsorbent materials, to effectively absorb wetness, keeping skin dryer and minimizing adverse skin effects.

Effect of Daily Use of the Bath Liquid on Skin Moisture, Including Polyquaternium-10 and Several Moisturizing Ingredients / 日本温泉気候物理医学会雑誌

  In recent years, because the dry skin problem has become very common, it is getting the more important to preserve the barrier function of the skin. Although protecting the skin against water loss is one of the representative factors of its barrier capabilities, there is no report until now about the relationship between daily use of bath liquid and the moisture-keeping capacity of the skin.<BR>  In this study we examined how the skin condition can be improved after 14 straight days of employment of our bath liquid ‘Ulmore<SUP>®</SUP>’including Polyquaternium-10 and several moisturizing ingredients. Polyquaternium-10 is a Cationized Cellulose and is widely formulated in shampoos and hair conditioners.<BR>  We found that the application of Ulmore<SUP>®</SUP> for 10 or 14 days significantly maintained sratum corneum water content (SCWC) and transepidermal water loss (TEWL) compared with the placebo application. This result suggests that this is because our bath liquid covered the stratum corneum and protected the skin from water loss caused by the environmental factors like low humidity.<BR>  Thus we conclude that daily use of the bath liquid has a beneficial effect on skin moisture.

Effect of Daily Use of the Bath Liquid on Skin Moisture, Including Polyquaternium-10 and Several Moisturizing Ingredients / 日本温泉気候物理医学会雑誌

  In recent years, because the dry skin problem has become very common, it is getting the more important to preserve the barrier function of the skin. Although protecting the skin against water loss is one of the representative factors of its barrier capabilities, there is no report until now about the relationship between daily use of bath liquid and the moisture-keeping capacity of the skin.   In this study we examined how the skin condition can be improved after 14 straight days of employment of our bath liquid ‘Ulmore®’including Polyquaternium-10 and several moisturizing ingredients. Polyquaternium-10 is a Cationized Cellulose and is widely formulated in shampoos and hair conditioners.   We found that the application of Ulmore® for 10 or 14 days significantly maintained sratum corneum water content (SCWC) and transepidermal water loss (TEWL) compared with the placebo application. This result suggests that this is because our bath liquid covered the stratum corneum and protected the skin from water loss caused by the environmental factors like low humidity.   Thus we conclude that daily use of the bath liquid has a beneficial effect on skin moisture.

Relievene® SK: neuroimunomodulação para o tratamento dermocosmético da pele sensível / Relievene® SK: neuroimunomodulation for dermocosmetic treatment of sensitive skin

Pele sensível (PS) é definida como uma condição de tolerância reduzida ao uso freqüente ou prolongado de cosméticos e produtos de higiene pessoal, que apresenta desde sinais clínicos visíveis, como eritema, edema e descamação, até sinais neurossensoriais subjetivos de desconforto, como pinicamento, queimação, prurido, ressecamento e dor. A fisiopatologia da PS consiste em reação inflamatória decorrente de uma disfunção da barreira cutânea associada ao desequilíbrio da resposta neuroimunoendocrinológica da pele. Neste trabalho demonstramos os efeitos do produto Relievene® SK sobre a proteção do metabolismo celular, considerando as atividades adaptógena e neuroendócrina deste composto, bem como a melhora da função da barreira cutânea e da hiper-reatividade da pele em indivíduos com PS.

Impact of synthetic urine at different pH values on skin surface pH / 中华皮肤科杂志

Objective To investigate the impact of synthetic urine (synurine solution) at differentpH values on skin surface.Methods Sixty-four healthy volunteers were enrolled into this study.Based on the results of lactic acid test and questionaires,these subjects were enrolled as sensitive skin group and normalskin group.The 4-,20-,and 24-hour occlusive patch tests were successively performed with synthetic urine at various pH values (2.0,3.5,5.0,6.5,8.0 and 10.0)on the two groups of volunteers.The distilled waterand 0.25%sodium lauryl sulphate (SLS)served as control.The skin surface pH values were measured bypotable pH meter before,and at 24 h,48 h,72 h after the first patch.Half an hour after the latter three detections of pH values,the skin response was evaluated clinically,as well as by transepidermal water loss (TEWL)and pH values,which were measured by pH-900 pH Meter.Results The responses to these solutions were similar between sensitive and normal skin groups.The order of skin surface pH values measured by the two pH meters was consistent with that of the original solutions.The skin surface pH value was altered by the synthetic urine,and this change was still present at 24 hours after the patches were removed.The TEWL values of skin challenged by synthetic urine were not higher than those by distilled water.The skin responses at 72 hours were more intense to the synthetic urines with pH values of.5,8.0,10.0than to distilled water.CondusionsSynthetic urines with different pH values can alter skin surface pH values,and skin responses to synthetic urines with a pH range 2.0-10.0 are similar to those to distilled water.

A Study on the Induction of Hardening Phenomenon by Repeated Application of Sodium Lauryl Sulfate / 대한피부과학회지

BACKGROUND: Chronic irritant contact dermatitis, the common occupational dermatitis of the skin, could be caused by repetitive exposure of the skin to irritants. Adaptation of the skin to repeated influence of exogenous irritants is called the hardening. The defining characteristic of hardening phenomenon has been progressively decreasing inflammatory response with prolonged exposure to an irritant. OBJECTIVE: The purpose of this study was to evaluate the induction of hardening phenomenon by the repeated application of various concentrated sodium lauryl sulfate (SLS) solutions. METHODS: Once a day a 0.1%, 0.5%, 2% solution of SLS and distilled water were applied to the volar forearm skin in 15 healthy volunteers for 10 minutes over 3 weeks. After 3 weeks interval of rest, patch tests with 1% solution of SLS were conducted on previously irritated sites for 24 hours. We measured transepidermal water loss (TEWL) and erythema index (E-index) before irritation, during 3 weeks of repeated application. 4 days after the patches test, we measured TEWL and E-index once a day. RESULTS: During 3 weeks of irritation with repeated application of 0.1%, 0.5%, 2% SLS solution, increase of TEWL was accelerated according to concentrations of SLS. In the study of 24-h patch test with 1% SLS solution on previously irritated sites after 3 weeks interval of rest, TEWL on distilled water application site was significantly higher than other sites irritated with SLS solution on D44 and D45. The TEWL values on the site irritated with higher concentration of SLS solution were lower than those with lower concentration of SLS solution. In contrast, there were no significant differences in E-index value during 3 weeks of irritation and after 24-h patch test with 1% SLS solution. CONCLUSION: Hardening could be induced by repeated irritation with SLS solution for 3 weeks. We suggest that hardening could be induced more efficiently with the higher concentration of SLS solution than the lower concentration.

Expression of Antimicrobial Peptides according to Changes of Transepidermal Water Loss Levels in Patients with Atopic Dermatits

BACKGROUND: The innate immune system of human skin contains antimicrobial peptides(AMPs) known as cathelicidins(LL-37) and human beta-defensins(hBD)-2. These peptides immediately respond to intruded microbes for prevention of further invasion. In normal skin these peptides are negligible, but they are accumulated in the skin affected by inflammatory diseases such as psoriasis. Although atopic dermatitis(AD) is recurrent inflammatory skin disease, it has been known that the expressions of AMPs in AD are decreased compared to that of psoriasis. OBJECTIVE: Current research was to identify the expressions of AMPs according to changes transepidermal water loss(TEWL) levels in AD. METHODS: The involved and uninvolved sites of patients diagnosed as having AD were evaluated using TEWL. And the expression of LL-37 and hBD-2 in skin biopsies specimens from involved and uninvolved site of these patients were determined by RT-PCR, Western blotting and immunohistochemical staining(IHC). RESULTS: The TEWL levels increased in both uninvolved and involved sites, more increased in involved sites. It implicated that permeability barrier function was more disrupted in involved sites of atopic dermatitis. In RT-PCR, the expression levels of hBD-2 and LL-37 mRNA were down-regulated in both uninvolved and involved sites, more decreased in involved sites. In Western blotting of hBD-2 and LL-37 proteins, the levels of hBD-2, LL-37 protein expressions of uninvolved sites were determined to be more intense than those observed in the involved sites. These findings were also confirmed by IHC. CONCLUSION: Our results demonstrate that expression of antimicrobial peptides downregulated according to increasing TEWL levels in atopic dermatitis lesions. Therefore, this deficiency may account for the susceptibility of patients with atopic dermatitis to skin infection, also implicate that localized skin barrier disruption play a role for decreased the expression of AMPs.

Change of Skin Barrier Function According to Stratum Corneum Removal by Tape Stripping / 대한피부과학회지

BACKGROUND: The major function of the skin is to prevent loss of water and electrolytes and transepidermal penetration of harmful materials. The stratum corneum is known to play a major role in the skin barrier function. Tape stripping (TS) with adhesive cellophane tape is one of the best method of removing the stratum corneum on the skin surface, and has been used in studies of the skin barrier function when investigating material distribution in the stratum corneum and transepidermal absorption of drugs. OBJECTIVE: This study was performed to evaluate the skin barrier function according to removal of the stratum corneum by TS. METHOD: Six vitiligo patients who had undergone autologous suction blister grafting were tested. Transepidermal water loss (TEWL) was measured on the normal skin of the buttocks in each patient after every fifth TS, plus on the skin where the entire epidermis had been removed by autologous suction blister grafting. We compared these two values and also examined morphological change of the stratum corneum after TS, by both light and electron microscope. RESULTS: The TEWL value slightly increased when TS was carried out up to 30 times, but greatly increased to 20g/m2h of TEWL when TS was done 30-40 times. Thereafter, no increase in TEWL was observed when TS was carried out up to 100 times. The pattern of TEWL according to numbers of TS approximately plotted a sigmoid curve. On average, there was about 88% impairment to the skin permeability barrier function after TS. When the TEWL increased to more than 70g/m2h over baseline TEWL, the stratum corneum was almost removed, as revealed by light and transmission electron microscope. CONCLUSION: The stratum corneum acts as a major skin barrier, and the mid to lower portion of the entire stratum corneum appears to play a significant role in the skin permeability barrier function.

Comparison of the Effect of Various Chemical Peeling Agents on the Skin Barrier / 대한피부과학회지

BACKGROUND: Among the various methods for chemical peeling, it is possible to select a wide range of peeling agents for particular patients. OBJECTIVES: The objective of present study was to investigate the effects of various chemical peeling agents on the epidermal permeability barrier of hairless mice skin and to clarify the histologic alteration in epidermal structure, thus to apply in the clinical practices. METHODS: We have applied 35% and 70% glycolic acid (GA) aqueous solutions, 30% of salicylic acid (SA) solution of PEG400, Jessner's solution and 15%, 30% and 50% of trichloroacetic acid (TCA) aqueous solution to the flank of hairless mice. TEWL (trans-epidermal water loss) values were measured before and immediately after the application and 3, 6, 12 and 24 hours following treatment. Biopsy specimens were evaluated with light and electron microscopy for epidermal structural changes. RESULTS: There were no significant changes in TEWL for the GA and SA solution treated skin, regardless of their concentration. For the TCA and Jessner's solution, TEWL increased immediately after treatment and recovered the basal levels about 90% after 24 hours for Jessner's solution and low concentrated TCA solution, but did not recovered for high concentrated TCA solution. On light and electron microscopic examination, exfoliating effect was seen in every case and as for SA and Jessner's solution treated skin, keratolysis at hair follicles was also seen. Slight epidermal necrosis was seen in every case, except in GA treated skin. CONCLUSION: The present results suggest that using topical agents such as glycolic acid can induce the change in the architecture of the epidermis without disrupting the skin barrier.

Effects of Beta Hydroxy Acid on the Facial Skin in Acne Patients / 대한피부과학회지

BACKGROUND: Several studies demonstrated that high concentration salicylic acid (beta hydroxy acid, BHA) peels were beneficial for acne, post inflammatory hyperpigmentation, melasma, oily skin, enlarged pores and surface roughness. OBJECTIVE: We have focused on the facial skin in acne patients after several BHA peels. METHODS: Thirty patients with acne vulgaris were included in this study. The peels were performed at 2 week intervals and sixteen patients completed a series of five peels. Stratum corneum hydration, skin surface lipid, skin pH, transepidermal water loss(TEWL) were measured at each visit and 2 weeks later after the last peel. RESULTS: The stratum corneum hydration, skin surface lipid, skin pH, TEWL did not show a statistically significant difference between the value of pretreatment and after five peels CONCLUSION: The results of this study suggest that BHA peels can be used to treat acne patients without disruption of normal skin function.

The Effect of Bentonite and Glycolic Acid on the Stratum corneum

BACKGROUND: Bentonite clay, which is a major component of mud pack, has been used for various purposes in cosmetics. Glycolic acid is known to be effective in the treatment of acne. Al-though those products are used widely, information on the mode of action and effects on the skin are little and controversial till now. OBJECTIVE: To investigate whether bentonite alone, or bentonite with glycolic acid in mixed formulation affect the stratum corneum leading to alteration on cutaneous barrier function and whether those products alter the lipid lamellae and desmosomes of corneocytes. MATERIALS AND METHODS: Mud pack-type ointment of bentonite, bentonite and 5% glycolic acid formulation, bentonite and 10% glycolic acid formulation were applied on the volar fore-arm of the five healthy men and flank skin of five 6-8 week old hairless mice. Transepidermal water loss and capacitance were measured. Electron microscopic examination after ruthenium tetroxide postfixation was performed on the flank skin of the mice. RESULTS: Transepidermal water loss(TEWL) increased immediately and normalized 4 to 6 hours later after removal of vapor permeable membrane in both mouse and human. Capacitance did not show any evidence of change in the water content of the stratum corneum. Electron microscopic examination revealed that lipid lamellae and desmosome of corneocytes were not de-graded, but lamellar body secretion and partially electron-lucent material was-increased in 10% glycolic acid and bentonite mixture-treated area. CONCLUSION: Barrier function of stratum corneum is not disturbed by bentonite and glycolic acid formulations at the concentration used. Barrier structures are not disrupted, but lamellar body secretion and partially electron-lucent material was increased by bentonite and glycolic acid formulations at higher concentration.

Changes of Transepidermal Water Loss (TEWL) in Psoriatic Plaques during D-PUVA Therapy

BACKGROUND: Psoriatic lesions have reduced water-holding capacity and show increased transepidermal water loss (TEWL). The effect of D-PUVA therapy, which combines topical calcipotriol and PUVA therapy, on epidermal barrier function has not yet been evaluated. OBJECTIVE: The purpose of this study was to verify the change of TEWL in lesional and normal skin according to D-PUVA therapy in psoriasis patients. METHODS: TEWL was measured consecutively by TEWAMETER TM210®, in 13 psoriasis patients who received D-PUVA therapy. Clinical grading was done according to psoriasis severity index (PSI). RESULTS: TEWL of psoriatic lesion decreased as D-PUVA continued. TEWL of normal-looking skin gradually increased, although the increase was trivial. Clinical grading of scale and in-filtration followed the pattern of PSI in the decrease of TEWL, while that of erythema did not. CONCLUSION: In psoriatic plaques, TEWL was decreased according to the improvement. In normal-looking skin, D-PUVA therapy caused only a little effect on TEWL.

Evaluation of the Skin Barrier Function by TEWL Measurement in Hypertrophic scars and Keloids / 대한피부과학회지

BACKGROUND: Hypertrophic scars and keloids have been regarded as representative of the proliferative change of the connective tissue of the dermis. Clinically, postburn and surgical scars show a smooth, shiny, erythematous appearance at an early stage. It is readily conceivable that, in such scars, changes may take place not only in the dermis but also in the epidermis and, possibly in the stratum corneum (SC). However, in contrast to the tremendous number of studies of scars on the dermis, those studies focusing on the epidermis and the SC have been scarce. OBJECTIVE: We have focused on the function of the SC covering the post-burn scar tissue and keloids. METHODS: Using noninvasive bioengineering measurements of functional properties of the SC, such as transepidermal water loss(TEWL), we evaluated the SC barrier function in various types of healing wounds, such as early erythematous lesion, hypertrophic scar, keloid, healed atrophic scar, scar occurring at the recipient site of the skin grafts and the adjacent normal appearing skin for control. RESULTS: 1. The TEWL values were 14.9+/-7.3 in early erythematous lesions, 13.2+/-7.5 in hypertrophic scars, 10.2+/-5.8 in keloids, 5.6+/-1.3 in healed atrophic scars, 6.9+/-4.3 in scars occurring at the recipient site of the skin grafts. Significantly increased TEWL values were found in all individual lesions(p>0.01) except for the scars occurring at the recipient site of the skin grafts(p<0.05) compared with the corresponding normal control skin. 2. When we randomly compared early erythematous lesions, hypertrophic scars, kelids, atrophic

Effects of Immersion on the Recovery of Epidermal Barrier after Acute Perturbation / 대한피부과학회지

BACKGROUND: If the skin is kept in continuous contact with water or other solutions after acute barrier perturbation, the pattern of barrier recovery will be different from that of the air exposure state at room temperature. Changes in the concentration of the solution also make a difference in the pattern of barrier recovery. However, there have been only a few studies on the difference of the barrier recovery or the changes in stratum corneum lipid between cases in the water immersion state and the air exposure state. OBJECTIVE: We studied the effect of immersion on the recovery of the epidermal barrier after acute perturbation so as to give aid to the basic research of the epidermal barrier and clinical application in prevention and treatment of contact dermatitis, hand eczema, and other occupational dermatoses. METHODS: After disruption of the epidermal barrier by tape stripping, hairless mice were immersed in temperature regulated hypotonic, isotonic, or hypertonic solutions, respectively. The pattern of barrier recovery with time was evaluated and compared with that of the air exposure group by means of TEWL measurement, and histochemical stain with Nile red. RESULTS: Immersion into water or solution without time to recovery after epidermal barrier disruption makes the recovery rate slower than that of the air exposure group except for the isotonic solution immersing group. CONCLUSION: For the normal recovery or prevention of the deterioration of the epidermal barrier, we should keep in mind to avoid the exposure to water or other solutions when acute or chronic barrier perturbation has developed. In addition, it would be better to use normal saline or other isotonic solutions, which do not disturb the normal barrier recovery process, to decrease damage to the epidermal barrier when it cannot help immersing into the solution.

Transepidermal Water Loss in Patients of Eczematous External Otitis / 대한이비인후과학회지

The difference of transepidermal water loss(TEWL) between normal persons and patients with eczematous external otitis was identified by statistical analysis. In this study, 20 healthy volunteers without history of atopic dermatitis and 20 patients with eczematous external otitis were participated. Measurements were performed at ear lobes and other various anatomical sites(proximal forearm, mid forearm, distal forearm, palm, upper back, lower back, leg(shin), leg(calf), and sole) by Tewameter TM 210(Courage;Rhazaka, Koln, Germany). Prior to the procedure, subjects stayed still for 30 minutes in the room where the temperature was controlled(18-23degreesC) with a relative humidity of 35-45%. The results are summarized as follows:1) TEWL values at ear lobes were higher in patients with eczematous external otitis than in normal persons(p<0.05). 2) TEWL values at other various anatomical sites except upper back were higher in patients with eczematous external otitis than in normal persons(p<0.05).

Skin Barrier Function Evaluated by Transepidermal Water Loss and Vascular Response to Percutaneous Absorption of Methyl Nicotinate / 대한피부과학회지

BACKGROUND: The measurement of transepidermal water loss(TEWL) is widely used in evaluating the stratum corneum barrier function. It is also possible to evaluate the penetration of substances into the skin as an additional parameter of the straturn corneum barrier function. OBJECTIVE: The purpose of the present study is to investigate ihe relationship between TEWL and the percutaneous absorptic n of methyl nicotinate(MN) in the normal and acute perturbative state of the epidermal barrier. METHOD: Vascular response 10 MN penetration were rneasured by both laser Doppler flowmetry (LDF) and visual erythema oii the forearms of 30 healthy volunteers. Stratum corneum of the ar ea of 2x10cm on the volar for earm was removed by repeated tape stripping when TEWL reached 12-30g/rnh measured with Evaporimeter. The left forearm received no treatrnent as a control site. Each time the profile of the vascular response to MN penetration was analysed using the following parameters:the 1ag-time between MN application and initial response(T0), the time between MN application and maximal response(T(max)), and the rnaximal response(LDF), the time between MN application and initial visual erythema(VT0), and the time between MN application and maxirnum visual erythema(VT(max)). RESULTS: The data showed a negative correlation between TEWL and T0(r=-12.89, p0.05). CONCLUSION: Vascular response to percutaneous absorption of MN measured by LDF as well as TEWL is a useful non-invasiv method for objective evaluation of the stratum corneum barrier function. In addition, visual erythema induced by topical vasodilators such as MN is also a good method for skin barrier function assessment.

The Effect of Chamber Size and Vulume of Test Solution on Cutaneous Irritation / 대한피부과학회지

BACKGROUND: There are some variables including chamber size in irritant patch test responses. Several non-invasive bidengineering methods for quantifying and obtaining information have been developed in recent decades. OBJECTIVE: Our study was done to compare the effect of chamber size and the volume effect on the irritation potential of 1% SLS solution. METHODS: Patches with 1% sodium lauryl sulfate(SLS) solution were applied to the volar forearm of 14 healthy volunteers for 24 h. Finn chambers with 8mm(20ul), 12mm(60pl), 18mm(80ul, 200ul) inner diameters were used. Visual score and transepidermal water loss (TEWL) were measured at 30 min after removal of the patches, and every 24 h up to 4 days. RESULTS: The results are summarized as follows. 1. Visual scores were 0.18+0.32(8mm), 0.75+0.33(12mm) and 0.64+0.41(18mm) at 24 h after removal of 1% SLS and were 0.11+0.29, 0.50+0.34 and 0.25+0.26 on 4 days after removal. They were inereased 30 min and 24 h after removal and decreased towards normal 4 days after removal. By chamber size, the skin response with the large Finn chamber(12mm) increased more significantly than with the small Finn chamber(8mm). However, there were no significant differences in skin response between large and extralarge Finn chambers(18mm). 2. TEWL values were 11.86+4.09, 23.05+6.1l and 22.24+7.54g/m/h at 30 min after removal and were 9.37+2.30, 1..49+3.08 and 14.56+5.00g/m/h on 4 days after removal. They were increased 30 min after removal and decreased towards normal 4 days after removal. By chamber size, their results were the same as visual scores. 3. By visual score and TEWL, the skin response with 200pl of 1% SLS increased more significantly than 80pl in the extralarge Finn chamber. CONCLUSION: The small Finn chamber may be too small to elicit sufficient cutaneous irritation for evaluation. The large Finn chamber having larger test areas may be suitable to yield positive reactions to certain irritants. Also, the quantity of test solution per mm skin may be of importance for the skin response.

Cutaneous Irritation to Sodium Lauryl Sulfate and Sodium Lauroyl Glutamate / 대한피부과학회지

BACKGROUND: Sodium lauryl sulfate(SLS) is the most widely utilized model for studying acute and cumulative irritation. Sodium lauroyl glutamate(SLG) has exhibited a low irritation potential and an anti-irritating effect on other anionic surfactants. OBJECTIVE: Our study was done to compare the skin irritancy of SLS and SLG using non-in- vasive techniques. METHODS: Patches with 1% SLS and SLG solution were applied to the volar forearm of 20 healthy volunteers for 24 h. Finn chambers with 8mm(20pl) and 12mm(60pl) inner diameters were used. Visual scores, transepidermal water loss(TEWL) and an erythema(E)-index were measured at 30 min after removal of the patches, and every 24hours(h) up to 4 days. RESULTS: The results are summarized as follows. 1. Visual scores were 0.20+0.30(8mm) and 0.73+0.34(12mm) at 24 h after removal of 1% SLS and were 0.15+0.29(8mm) and 0.30+0.41(12mm) at 24 h after removal of 1% SLG. They were increased at 30 min and 24 h after removal and decreased towards normal at 4 days after removal. By chamber size, the skin response with large Firin chamber(12mm) increased more significantly than with the small Finn chamber(8mm). In the small Finn chamber, there were no significant differences in the skin response between 1% SLS and 1% SLG. In the large Finn chamber, the skin response with 1% SLS increased more significantly than with 1% SLG. 2. TEWL values were 11.14+4.77(8mm) and 20.48+10.61(12mm) at 24 h after removal of 1 % SLS and were 10.38+3.99 and 14.87+7.46 at 24 h after removal of 1% SLG. They were increased at 30 min after removal and decreased towards normal 4 days after removal. By chamber size, their results were the same as the visual scores. Also, on comparison between 1% SLS and 1% SLG, their results were the same as the visual scores. 3. E-index was 10.05+2.70(8mm) and 11.15+2.56(12mm) at 24 h after removal of 1% SLS and was 10.15+2.16 and 10.60+2.26 at 24 h after removal of 1% SLG. They were increased at 30 min after removal and decreased towards normal 4 days after removal. By chamber size, their results were the same as the visual scores. In the small and large Finn chamber, there were no significant differences in the skin response between 1% SLS and 1% SLG. CONCLUSION: SLS is more irritating than SLG. The large Finn chamber may be more suitable to yield positive irritant reactions than the small Finn chamber. Also, TEWL measurements may be a more accurate and sensitive method than the E-index.