The difference between the constitutive and facultative skin color does not reflect skin phototype in Asian skin

BACKGROUND/PURPOSE: The assessment of the sensitivity of human skin to ultraviolet (UV) radiation is important in the area of phototherapy, photodermatoses, photo-aging, photo-carcinogenesis, and photo-protection. Some reports have shown that quantitatively measured skin color is a good indicator for predicting UV sensitivity to human skin in Caucasians. In this study, our aim was to define the correlation between skin color and the skin phototype assessed by the Fitzpatrick method in Asian brown skin. METHODS: A total of 180 medical students with similar life styles were included in this study. Their skin phototype was classified according to the system introduced by Fitzpatrick. Then, using a Minolta Spectrophotometer CM-2002, their skin color was determined on the buttocks and forehead. The buttock color was taken as the constitutive skin color, and the forehead color as the facultative skin color. Using these measured values, we compared the skin color with the skin phototype to find their correlation. Also, we investigated whether the difference between the constitutive and facultative skin colors of each individual had a relationship with his or her skin phototype. RESULTS: The constitutive skin color became darker with increasing skin phototype, and this change was statistically significant. As for the facultative skin color, it also became darker with increasing skin phototype, but was less well correlated with the skin phototype than the constitutive skin color. However, the difference between the constitutive and facultative skin colors did not show consistent results in predicting the skin phototype. CONCLUSION: In this study, we found that the constitutive skin color can be a good indicator of the skin phototype. However, the difference between the constitutive and facultative skin colors of each individual does not give any meaningful information for the assessment of his or her skin phototype in Asian skin.     

Amputee skin condition: occlusion,stratum corneum hydration and free amino acid levels

Patients with a prosthetic limb report negative skin effects, including irritation, rash and chaffing, which can lead to infection, discomfort and reduced wear time to significantly impact normal activities. The aims were to examine the epidermal integrity (transepidermal water loss, TEWL), stratum corneum (SC) hydration [moisture accumulation rate (MAT)], friction and biomechanical properties in active below the knee amputees and to determine the effects of an inert sock liner on skin condition. The liner reduced hydration, TEWL and friction and increased elasticity versus the amputee’s conventional skin care methods. Residual limb TEWL was increased and MAT was reduced versus the contralateral normal skin. In a second study, we hypothesized that complete occlusion would decrease free amino acids (FAA) and quantified them by high performance liquid chromatography in an adult volar forearm model. Occlusion with a water vapor impermeable wet dressing led to increased TEWL, erythema and dryness and reduced MAT versus normal skin, comparable to the results in the amputees. The FAA levels were significantly reduced for the occluded sites. The results suggest that residual limb occlusion in amputees may block the formation of FAA in the upper SC. Therapies based on replacement of water binding FAAs, may alleviate the consequences of long-term occlusion.     

Positive photocontact responses are not elicited to sunscreen ingredients exposed to UVA prior to application onto the skin

Photocontact allergic reactions to sunscreen chemicals are investigated by photopatch testing. It has generally been assumed that for photocontact allergy to be shown, the putative pro-allergen must be in the skin at the time of ultraviolet A (UVA) exposure. However, this assumption has not, to our knowledge, been tested. The objective of this study was to determine whether positive photocontact responses can still be elicited when sunscreen chemicals are exposed to UVA prior to application onto the skin. 3 patients known to have positive photocontact reactions to a total of 6 sunscreen chemicals were studied. For conventional photopatch testing, patch test strips were applied onto the back and removed 1 D later, and the area was irradiated with UVA (5 J/cm(2)). For pre-irradiated testing, patches were exposed to the same dose of UVA immediately before application onto the back and then removed 1 D later. Skin responses were visually assessed by a blinded investigator 1 and 2 D after patch test removal. The same photocontact responses of the same magnitude, as previously documented for each patient, were seen at each of the conventional UVA-exposed patch test sites. However, in no patient was a positive response elicited at any of the sites where pre-irradiated patches had been applied. This study shows that positive photocontact responses to sunscreen chemicals do not occur when the putative pro-allergen is irradiated prior to application onto the skin. This suggests that for a photoallergic reaction to occur, the sunscreen chemical needs to be within the skin when activated by UVA.     

Impact of glove occlusion on cumulative skin irritation with or without hand cleanser–comparison in an experimental repeated irritation model

Background. Irritant contact dermatitis remains a substantial problem in the food processing industries. Irritants that are weak by themselves, such as glove occlusion and mild detergents, could interact to produce contact dermatitis. Objectives. To model the irritant action of an antibacterial hand cleanser and glove occlusion, with sodium lauryl sulfate (SLS) as a positive control. The effects of a pre‐exposure cream and a post‐exposure cream were also investigated. Methods. A modified repeated short‐time occlusive irritation test with 20 healthy volunteers, and application of irritants over 4 days, with pre‐exposure and post‐exposure creams and overnight glove occlusion, was performed. The changes in transepidermal water loss (TEWL) served as a measure of the irritant damage to the epidermal barrier. Results. The antibacterial cleanser and the glove occlusion separately induced only minor increases in TEWL. When combined, the two showed a tandem effect, as the TEWL increase was significantly higher, and was similar to that seen with the positive control, SLS. The pre‐exposure and post‐exposure creams alone significantly mitigated the cumulative irritation, and this effect was strongest when the two creams were combined. Conclusions. Irritant contact dermatitis may develop through the tandem effects of long‐term glove occlusion and the accumulation of barrier damage from hand washing, even when mild hand cleansers are employed.     

Occupational dermatoses in workers exposed to resins based on phenol and formaldehyde

During December 1985 and February 1986, an investigation was carried out into skin diseases among workers in a plant producing decorative equipment built of paper sheets impregnated with resol resins based on phenol and formaldehyde (P-F-R). A questionnaire was sent to all 238 employees and it was answered by 218 (91.6%). Previous and current dermatoses were reported by 98 workers and 89 of these were examined and patch tested. The patch testing was conducted with a standard test series and products from the working environment and revealed contact allergy to P-F-R in 9 persons and to formaldehyde in 1. Besides these 10 individuals with occupational allergic contact dermatitis, occupational dermatoses were diagnosed in an additional 20 workers; irritant contact dermatitis in 19 and chemical burn in 1. In total, the figure for occupational dermatoses was 30 (12.6%).     

Lichen ruber only in skin areas exposed to light

In a patient with lichen ruber, skin lesions appeared exclusively on sun-exposed sections of the body. This localization is atypical in Europe. In tropical and subtropical countries lichen ruber actinicus can be observed in up to 30% of the population.     

PARP determines the mode of cell death in skin fibroblasts, but not keratinocytes, exposed to sulfur mustard

Sulfur mustard is cytotoxic to dermal fibroblasts as well as epidermal keratinocytes. We demonstrated that poly(ADP-ribose) polymerase (PARP) modulates Fas-mediated apoptosis, and other groups and we have shown that PARP plays a role in the modulation of other types of apoptotic and necrotic cell death. We have now utilized primary dermal fibroblasts, immortalized fibroblasts, and keratinocytes derived from PARP(-/-) mice and their wildtype littermates (PARP(+/+)) to determine the contribution of PARP to sulfur mustard toxicity. Following sulfur mustard exposure, primary skin fibroblasts from PARP-deficient mice demonstrated increased internucleosomal DNA cleavage, caspase-3 processing and activity, and annexin V positivity, compared to those derived from PARP(+/+) animals. Conversely, propidium iodide staining, PARP cleavage patterns, and random DNA fragmentation revealed a dose-dependent increase in necrosis in PARP(+/+) but not PARP(-/-) cells. Using immortalized PARP(-/-) fibroblasts stably transfected with the human PARP cDNA or with empty vector alone, we show that PARP inhibits markers of apoptosis in these cells as well. Finally, primary keratinocytes were derived from newborn PARP(+/+) and PARP(-/-) mice and immortalized with the E6 and E7 genes of human papilloma virus. In contrast to fibroblasts, keratinocytes from both PARP(-/-) and PARP(+/+) mice express markers of apoptosis in response to sulfur mustard exposure. The effects of PARP on the mode of cell death in different skin cell types may determine the severity of vesication in vivo, and thus have implications for the design of PARP inhibitors to reduce sulfur mustard pathology.     

P67Hand eczema, skin exposure and glove use in dental technicians

Objective:  Exposure to adhesives and glues is common in occupation. We here analyse the data of patients with suspected contact dermatitis (CD) from glues recorded within the Information Network of Departments of Dermatology (IVDK).
Methods:  Data recorded between 1996 and 2001 within the IVDK were searched for patients who underwent patch testing because of suspected contact dermatitis from glues.
Results:  Overall data of 829 patients were found, among them 336 with occupational skin disease. Allergic CD was diagnosed in 171/336 patients (50.9%), irritant CD in 24.7%. CD was mostly localized on the hands (72.6%), followed by the face (13.4%) and arms (3.9%). By far the most common cause of an allergic patch‐test reaction was epoxy resin (EP): 18.2%(age‐ and sex‐standardized proportion of sensitization) reacted to the standard EP based on diglycidylether of bisphenol A. reactive diluents and hardeners which elicited a positive patch‐test reaction in > 5% of the patients were phenyl glycidylether and 4,4'diamino diphenylmethane respectively. Cresyl glycidylether was positive in 4.9%. (Meth‐)acrylates which showed an allergic patch‐test reaction in >= 5% of the patients were 2‐hydroxypropyl methacrylate, hydroxyethyl acrylate, 2‐hydroxyethyl methacrylate, ethyleneglycol dimethacrylate, BIS GMA and triethyleneglycol dimethacrylate. Colophony was positive in 8.3% and p‐tert‐butylphenol formaldehyde resin in 4.1% of the patients respectively.
Conclusion:  In our collective allergic CD was nearly 2‐fold more frequent than irritant CD in patients with occupational CD from glues, epoxy resin components being the most important allergens.     

Hand dermatoses and contact allergic reactions in construction workers exposed to epoxy resins

In 23/135 (18%) workers exposed to epoxy resins, a work-related dermatosis on the hands and/or forearms had been present during the past 3 years. In 9 persons, the occupational dermatosis was still present at the time of investigation. In all workers, patch tests were performed with epoxy resin, isophoronediamine, triethylenetetramine and xylenediamine. Positive patch tests were observed in 27 of the 135 exposed workers (20%) 13 of whom had never previously experienced skin problems. Epoxy resin accounted for the majority of the positive reactions. There was no relation between a history of atopy and the development of contact allergy. Only half of all workers had received any safety instructions. The wearing of gloves (mostly cotton), intended to protect the skin, had an adverse effect.     

Ethanol-modulated cytokine production and expression in skin cells exposed to methotrexate.

Evidence suggests a link between alcohol consumption, psoriasis and the response of psoriatic patients to methotrexate (MTX) therapy. Ethanol (EtOH) may play a role in the pathogenesis of psoriasis by upregulating the expression and inducing the local secretion of proinflammatory cytokines, e.g. interleukins IL-1alpha, IL-6, chemokine IL-8 and tumor necrosis factor alpha (TNF-alpha). We investigated whether EtOH or MTX or their combination influence the secretion of these cytokines using normal human primary skin cells (NHPSC) and epidermoid cell line A431. The objectives of this study were: (1) to quantify the differences in cellular changes induced by MTX, (2) to measure the effect of EtOH on MTX toxicity and (3) to determine the relationship between MTX and EtOH exposure and production of proinflammatory cytokines. NHPSC and A431 were incubated with 0-10 mM MTX or alpha-MEM (control) in the presence or absence of 40 mM EtOH. A formazan 3-(4,5-dimethylthiazole-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) assay was used as a marker for cell viability (control was 100%). Significance was calculated by ANOVA. Cytokine release into media was quantitated by ELISA. After 24 h of MTX exposure, the release of IL-1alpha was unchanged. IL-6 increased 1.7 times in both cultures, and IL-8 increased 1.7 times in NHPSC and 2.1 times in A431. TNF-alpha release increased twice in A431 but not in NHPSC. Human recombinant IL-1alpha and IL-6 for 24 h had no effect, while TNF-alpha reduced cytoviability by 30% in NHPSC and 22% in A431. Anti-TNF-alpha reversed the effect produced by TNF-alpha in NHPSC and reduced it in A431 (11.8%, p < 0.05). We concluded that in vitro in normal human primary keratinocytes, toxicity and inflammatory responses are enhanced by EtOH.     

No skin reactions to mineral powders in nickel-sensitive subjects

Background. Cosmetic products are known to be able to induce contact dermatitis. Contact dermatitis may also be induced by nickel, and it is estimated that up to 17% of women are allergic to nickel. Objectives. The aim of the present study was to investigate whether nickel sensitized individuals react to make‐up products containing pigments with nickel as an impurity. Patients/Materials/Methods. Twenty‐three individuals with a clinical history of nickel allergy and/or with positive patch test reactions to nickel were exposed to mineral make‐up products and individual pigments dispersed in alkylbenzoate (50%) in small Finn Chambers^® for 48 hr. The skin reactions were evaluated visually and with a non‐invasive instrument that quantifies skin erythema. Results. The results showed that 74% of the included individuals showed a visible reaction to the positive control nickel sulfate, and a significant correlation was found between the visual and instrumental readings. However, none of the nickel sensitive individuals reacted to the test products. A subgroup analysis of the 50% most sensitive individuals also confirmed the absence of skin reactions to the powders. Conclusions. The bioavailability of the trace amounts of nickel in the particles was below the level needed to elicit an eczematous reaction in any of the nickel‐sensitized individuals.     

Different in vivo reactivity profile in health care workers and patients with spina bifida to internal and external latex glove surface-derived allergen extracts

Background Allergy to natural rubber latex is a well‐recognized health problem, especially among health care workers and patients with spina bifida. Despite latex sensitization being acquired in health institutions in both health care workers and patients with spina bifida, differences in allergen sensitization profiles have been described between these two risk groups. Objective To investigate the in vivo reactivity of health care workers and patients with spina bifida to extracts of internal and external surfaces of latex gloves and also to specific extracts enriched in major allergens for these risk groups. Methods Gloves from different manufacturers were used for protein extraction, and salt precipitation and hydrophobic interaction chromatography (HIC) were applied to obtain the enriched latex extracts. The major latex allergens were quantified by an enzyme immunoassay. The extracts obtained were tested in 14 volunteers using skin prick tests (SPT). Results Latex glove extracts enriched in the hydrophobic allergens that are most often seen in patients with spina bifida were obtained by selective precipitation, whereas HIC produced extracts enriched in the hydrophilic allergens commonly found in health care workers. The health care workers had positive SPTs to glove extracts from internal surfaces and to the hydrophilic allergen‐enriched extracts. By contrast, patients with spina bifida had larger skin reactions both to external glove extracts and to the extracts enriched with the hydrophobic major allergens for this risk group. Despite the protein concentration of these extracts being less than half the concentration of the commercial extract, the weal‐and‐flare reactions were of similar magnitude. Conclusion Using novel latex extracts, our study showed a different in vivo reactivity pattern in health care workers and in patients with spina bifida to extracts of the internal and external surfaces of gloves, which suggests that sensitization may occur by different routes of exposure, and that this influences the allergen reactivity profiles of these risk groups.