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Query: UMLS:C0152030 (skin irritation)
 2,146 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Besides visual evaluation, skin irritation induced by sodium lauryl sulfate (SLS) may be characterized by bioengineering measurements, such as skin colour reflectance, transepidermal water loss (TEWL) or hydration. Short application times or low concentrations of the irritant usually do not modify the visual aspect of the skin, and the measurements described above are unchanged or only slightly altered. We were looking for a suitable method to measure cutaneous changes not detectable by usual bioengineering procedures. Therefore these measurements were compared to those of dynamic function testing of the stratum corneum, namely sorption-desorption and moisture accumulation tests. Different concentrations of SLS (0.1%, 0.5%, 2.5%), application times (15 min, 24 h) and times of testing (1 h, 24 h after patch removal) were investigated on the ventral forearm of human subjects. When SLS was applied for a short period (15 min), 1 h after patch removal skin colour, TEWL and hydration were not modified, while increases in hygroscopicity, water-holding capacity and water accumulation were detected depending on the applied concentration. Increase of hygroscopicity was closely correlated with the alteration of epidermal barrier function (TEWL). We demonstrated that sorption-desorption and moisture accumulation tests performed on SLS-treated areas for a short period, without visible modifications, could evaluate changes of the stratum corneum properties. We consider these tests as useful complementary methods to skin colour, TEWL and hydration measurements, particularly in the detection of subclinical skin injuries.
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PMID:Measurement of sodium lauryl sulfate-induced skin irritation. 889 Oct 3

Calcipotriol, a vitamin D analogue utilized for psoriasis, has irritation as its most frequent reported adverse event. However, studies on its irritant properties in humans have produced conflicting data. This study evaluates the effect of calcipotriol on stratum corneum barrier function, hydration and cell turnover in healthy volunteers, compared with sodium lauryl sulphate (SLS) as a model irritant. Calcipotriol 0.005% ointment and 1% aqueous SLS solution were applied for 60 min once daily for 2 weeks (5 consecutive days weekly) on untreated and on dansyl-chloride-labelled skin. Irritant responses were documented by visual scoring and by measurement of the transepidermal water loss (TEWL) and stratum corneum hydration (electrical capacitance), until day 18. Stratum corneum turnover time (SCTT) was the time in days between staining (day 0) and the disappearance of dansyl fluorescence. SLS caused more erythema, scaling, and a significant TEWL increase for 18 days. In contrast, calcipotriol induced erythema, and slightly but significantly increased TEWL on day 11 only, as compared with the vehicle control (P < 0.05). SLS, but not calcipotriol, caused skin dryness from day 4 to day 18. The shortest SCTT was obtained at SLS-exposed sites (11.2 +/- 0.7 days: mean +/- SD). Calcipotriol significantly shortened SCTT (16.3 +/- 1.1 days) when compared with its vehicle. Compared with the skin irritation induced by SLS, under these test conditions, calcipotriol is a far weaker irritant on normal human skin. In addition, calcipotriol accelerates stratum corneum turnover to a significantly greater extent than its vehicle.
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PMID:Effects of calcipotriol on stratum corneum barrier function, hydration and cell renewal in humans. 891 43

This study, conducted in 36 human volunteers, was an evaluation of the effects of saline iontophoresis on skin temperature, irritation, and barrier function. The major objectives were to assess the effects of low-level ionic currents, to validate the proposed methodology of assessment, and to establish reproducibility in repeated saline iontophoresis applications. This was the first of a multistage study designed to assess the safety of 24-hr saline iontophoresis episodes at selected currents and current densities. Since an iontophoresis patch challenges the skin barrier both by occluding the skin surface and by passing ionic current through the skin, the experimental protocol was designed to permit measurement of the contribution of each of these processes to the overall response. In this first stage we investigated the effect of 10 min of current delivery, at 0.1 mA/cm2 on a 1-cm2 area patch and 0.2 mA/cm2 on a 6.5-cm2 area patch compared to unpowered control patches. Twelve subjects were tested under each condition on two separate occasions to examine reproducibility of the response variable measurements. A further 12 subjects were tested once under the 0.2 mA/cm2, 6.5-cm2 condition. Skin irritation was evaluated via repeated measurements of transepidermal water loss, capacitance, skin temperature, skin color, and a visual scoring system, before the iontophoresis episode and after patch removal. No damage to skin barrier function in terms of skin-water loss or skin-water content was detected. Slight, subclinical, short-lasting erythema was observed for both conditions. Assessment of correlation coefficients showed highly statistically significant indications of reproducibility for all five response variables measured. The experimental design, in combination with a repeated measures analysis, provided clear separation of the occlusion and ionic current components of the iontophoretic patch challenge. Further, the repeated measures analysis gave a highly sensitive assessment of skin irritation and resolution after patch removal. We conclude that the experimental methodology is appropriate for assessing possible changes in skin integrity resulting from saline iontophoresis under similar operating conditions for longer durations and for other skin challenges from which a subclinical response is expected.
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PMID:The effect of saline iontophoresis on skin integrity in human volunteers. I. Methodology and reproducibility. 892 20

The socket of a prosthesis is a tightly closed container. Sweating inside the socket is annoying and may also irritate the skin over the stump or lead to local infection such as folliculitis. The most effective method of preventing sweating is by the use of astringent agents. Formaldehyde is a very strong astringent but is not pleasant to use and may cause skin irritation and systemic reactions. Methenamine, in water or when applied to the skin, decomposes to generate formaldehyde in small quantities which do not cause side effects. Methenamine was used on the stump of sixteen amputees. The trial was conducted as a double blind study using two different solutions market as solution A and as solution B. The effectiveness of the solutions as an antiperspirant was evaluated clinically by the subjects and the physician. Solution A containing Methenamine, was found significantly effective, both by the subjects and physician when compared with the solution B the blank one. The use of Methenamine as an antiperspirant is recommended in amputation stumps.
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PMID:The use of Methenamine as an antiperspirant for amputees. 898 96

Metalworking fluids (MWF) have been reported as being an important cause of irritant contact dermatitis in metal workers. Our purpose was to determine whether the irritancy of different MWF assessed by 2 different types of predictive human in vivo tests could be compared with epidemiological data. 3 water-based MWF were tested in the same panel of subjects. Reactions were assessed by a visual score (VS), evaporimetry to evaluate the transepidermal water loss (TEWL) and chromametry to quantify erythema. Test 1: MWF were applied with Finn Chambers on the volunteers' mid-back, removed after 1 day of exposure, and reapplied for a further 2 days. Test 2: Cumulative irritant contact dermatitis was induced using a repetitive irritation test for 2 weeks (omitting weekends) for 6 h per day. We observed an increase in VS, TEWL, and erythema for all MWF, with the same irritancy ranking in both test models. Differentiation of the substances was better in the D1/D3 test. The experimental results partially correlated with the epidemiological data. Considering the shorter application time and the better discrimination of irritancy, we prefer the D1/D3 model as a predictive test of MWF irritancy. Our results might aid development of a standardized test to reduce cumulative skin irritation in metal workers.
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PMID:Predictive testing of metalworking fluids: a comparison of 2 cumulative human irritation models and correlation with epidemiological data. 903 82

Skin irritant reactions are under the control of a network of cytokines and lipid mediators. This study characterized the production of tumor necrosis factor-alpha (TNF) induced by a skin irritant treatment, tributyltin (TBT), in mice through transcription factor activation and its pharmacologic modulation by anti-inflammatory agents. The ears of BALB/c mice were painted with different amounts of TBT (67-536 nmol in acetone) or with acetone alone. At different times thereafter, TNF production was analyzed both at the mRNA and protein level, by semiquantitative RT-PCR and L929 cytotoxicity assay, respectively. TBT induced rapid (1 h) TNF gene expression and protein synthesis. Maximal TNF production was observed 2 h after treatment. The production of TNF was paralleled by accumulation of skin water; this was partially prevented by intraperitoneal injection of antibody against murine TNF. These data indicate that skin irritation induced by TBT is attributable, in addition to the actions of other inflammatory mediators, to the action of keratinocyte-derived TNF. TNF production was preceded by a rapid (5 min) activation of nuclear factor-kappaB (NF-kappaB), which was also maximal 30 min after treatment. TBT-induced accumulation of skin water and TNF production were significantly reduced by topical treatment with dexamethasone and pentamidine, two anti-inflammatory agents. Interestingly, dexamethasone, but not pentamidine, decreased TBT-induced NF-kappaB activation, confirming in vivo that the glucocorticoid receptor interacts functionally within the nucleus with other transcription factors opposing one another's activity.
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PMID:Induction of tumor necrosis factor-alpha in vivo by a skin irritant, tributyltin, through activation of transcription factors: its pharmacological modulation by anti-inflammatory drugs. 918 17

As indicated by in vitro experiments the penetration of irritants through the skin is significantly influenced by the temperature of the solution. In vivo experiments, demonstrated equally a significant influence of temperature in surfactant-induced skin irritation. In order to evaluate the irritant potential of detergent solutions under normal user conditions, we used the hand/forearm immersion test. We compared 2 detergents with different anionic character in a repetitive immersion protocol (30 min immersion on 4 consecutive days). The solutions were tested at 2 temperatures (37 degrees C and 40 degrees C). The irritation was quantified by assessment of the stratum corneum barrier function (transepidermal water loss), skin redness (a* colour parameter) and skin dryness (capacitance method). Both detergents affected the integrity of the skin in a significant way. The anionic content as well as the temperature of the solutions were found to be determinative for the irritant potential, with a stronger response for higher anionic content and temperature, respectively.
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PMID:Influence of temperature on irritation in the hand/forearm immersion test. 919 57

Exposure of the skin to sodium dodecyl sulfate (SDS) leads to disruption of barrier and skin irritation. We used repetitive short exposure to a low molarity SDS solution as an in vivo model to mimic the development of irritant contact dermatitis. In this model, we studied clinical (erythema), functional (transepidermal water loss(TEWL)) and cell biological changes. 24 healthy volunteers were patch tested with SDS (0.2%) for 4 h a day for 5 consecutive days. After removal of the patches, the exposed sites were treated 1 X daily either with a topical corticosteroid (triamcinolon acetonide cream 0.05%), a retinoid (tretinoin cream 0.025%), or a vitamin D3 derivative (calcipotriol ointment 50 micrograms/g). Irritant reactions were assessed by erythema scoring and measurement of barrier function with TEWL up to 14 days after the first challenge. Skin biopsies were taken for cell biological changes at day 4. Vehicle-treated sites served as controls. Repetitive exposure of human skin to SDS resulted in a gradual increase in erythema scoring and TEWL associated with the upregulation of proliferative cells as measured by the expression of Ki-67-antigen and of differentiation markers, visualized by increased expression of involucrin and epidermal-fatty-acid binding protein (E-FABP). Skin irritation as assessed by erythema scoring and TEWL was not significantly suppressed by triamcinolone cream. However, a significant reduction of the number of cycling keratinocytes and a decrease in involucrin positive cell layers was observed in this group. Neither treatment with calcipotriol ointment nor with tretinoin cream induced improvement of skin irritation as judged by visual scoring and TEWL. In contrast to steroid treatment, no significant effect of calcipotriol ointment or tretinoin cream treatment was observed with regard to the number of cycling cells and differentiation markers. Further studies are needed to assess whether treatment with topical corticosteroids is an effective modality in skin irritation and irritant contact dermatitis.
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PMID:Effect of a topical corticosteroid, a retinoid and a vitamin D3 derivative on sodium dodecyl sulphate induced skin irritation. 925 81

In clinical practice, the cutaneous exposure to chemical irritants such as surfactants and topical drugs is frequent. Topical all-trans retinoic acid (RA) is often associated with irritation and induces epidermal changes similar to those produced by sodium lauryl sulphate (SLS). Using bioengineering techniques, e.g. assessing transepidermal water loss (TEWL), capacitance and chromametry, we investigated the variations of the skin response to SLS and RA and to both chemicals applied sequentially, allowing different time periods (from 1 h to 2 weeks) between applications of SLS and RA. Both chemicals caused irritation as assessed by visual scoring, but the values from the objective variables differed at different time periods. TEWL increased dramatically shortly after applying SLS but the increase was delayed after RA. After applying SLS, the capacitance generally decreased then returned to basal values; treatment with RA produced an overall increase. Only the results from chromametry were similar. After tandem application, the drugs were synergistic for all variables except capacitance, showing an antagonistic interaction for skin hydration. These results suggest that non-specific skin irritation profoundly reflects different mechanisms of action at tissue level. With sequential application, SLS injury modified the response to RA for at least 1 week after applying SLS. These late effects of detergents should be considered when studying irritant chemical interactions and in developing strategies for the management of occupational and other irritant dermatitis.
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PMID:Differential irritant skin responses to tandem application of topical retinoic acid and sodium lauryl sulphate: II. Effect of time between first and second exposure. 964 Apr

Alpha hydroxyacids (AHAs) are used to enhance stratum corneum desquamation and improve skin appearance. The purpose of this study was to evaluate whether some AHAs improve skin barrier function and prevent skin irritation. Eleven healthy subjects (aged 28 +/- 6 years, mean +/- SD) entered the study. Six test sites of 8 x 5 cm (four different AHAs, vehicle only (VE) and untreated control (UNT) were selected and randomly rotated on the volar arm and forearm. The four different AHAs at 8% concentration in base cream were glycolic acid (GA), lactic acid, tartaric acid (TA) and gluconolactone (GLU). The products were applied twice a day for 4 weeks (2 mg/cm2). At week 4, a 5% sodium lauryl sulphate (SLS) challenge patch test was performed under occlusion for 6 h (HillTop chamber, 18 mm wide) on each site. Barrier function and skin irritation were evaluated by means of evaporimetry (Servomed EP-1) and chromametry (a* value, Minolta CR200) weekly, and at 0, 24 and 48 h after SLS patch removal. No significant differences in transepidermal water loss (TEWL) and erythema were observed between the four AHAs at week 4. After SLS challenge, GLU- and TA-treated sites resulted in significantly lower TEWL compared with VE, UNT (P < 0.01) and GA (P < 0.05) both at 24 and 48 h. Similarly, a* values were significantly reduced after irritation in GLU- and TA-treated sites. This study shows that AHAs can modulate stratum corneum barrier function and prevent skin irritation; the effect is not equal for all AHAs, being more marked for the molecules characterized by antioxidant properties.
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PMID:Alpha hydroxyacids modulate stratum corneum barrier function. 947 Sep 10


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