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Background: There continues to be a need for objective, noninvasive methods to measure melanin concentration in vivo in human skin, independent of the confounding chromophore, haemoglobin. Existing methods are limited by a lack of specificity and inability to resolve the spatial distribution of these chromophores., Objectives: To validate and calibrate the measurement of eumelanin in vivo using SIAscopic techniques, relating this with histologically and analytically determined eumelanin concentrations in nonsun-exposed skin from subjects of Fitzpatrick skin types I-VI., Methods: Observations were made in five subjects from each of the Fitzpatrick skin types I-VI using chromophore mapping by contact and noncontact SIAscopy and other noninvasive spectrophotometric means. Measurements were performed on the inner aspect of both upper arms. Subsequently two 4 mm punch biopsies were taken from the inner upper arm, one per arm after injection of local anaesthesia. One biopsy was fixed in formalin and processed for histology; specifically, sections were stained for melanin using a silver staining technique and the amount of melanin was graded microscopically. The other biopsy was subjected to an analytical assay to yield precise quantitative measures of melanin. The correlation between the different methods of melanin measurement was determined., Results: Clear, significant correlations were obtained between contact and noncontact SIAscope-derived eumelanin values and actual eumelanin tissue content (determined both histologically and analytically), across the full range of Fitzpatrick skin types. There was no correlation between SIAscope-derived eumelanin and haemoglobin values, indicating efficient separation of the two chromophores., Conclusions: New contact and noncontact chromophore SIAscopic mapping techniques provide robust, rapid noninvasive measures of the concentration and spatial distribution of eumelanin in vivo, independent of haemoglobin, which correspond to true tissue values for this chromophore.

In vivo plasma profiles from formulations containing 5% ibuprofen were compared after a single topical application in a randomised, double-blind, cross-over trial. Ibuleve gel (Dermal Laboratories, UK) contained only ibuprofen whilst Deep Relief gel (Mentholatum, UK) also contained 3% menthol. In contrast to results obtained when these products were compared under in vitro conditions, there was no statistically significant difference in vivo between delivery of ibuprofen. Estimated relative bioavailability fraction (Deep Relief gel/Ibuleve gel) from log-transformed AUC((0-24h)) was 0.99 (95% CI: 0.94-1.04), estimated C(max )ratio was 0.96 (95% CI: 0.91-1.00) and estimated t(max) ratio was 1.01 (95% CI: 0.81-1.20). Menthol produces local vasodilation, which reduces skin barrier function, and these data demonstrate that it is inappropriate to extrapolate from in vitro data where formulation components produce biologically-mediated enhancement of permeation which cannot be modelled ex vivo. In clinical use, these products deliver comparable amounts of ibuprofen, but only Deep Reliefgel provides the secondary immediate benefit of the direct analgesic action of menthol., ((c) 2006 S. Karger AG, Basel)

Background: Financial and managerial constraints have resulted in the rationalization of dermatology inpatient services in the United Kingdom and the United States. Therapeutic regimes may vary locally, regionally, and internationally but the clinical outcome of treatment remains the same., Objective: We studied 2 inpatient units: the University of Wales College of Medicine, Cardiff, United Kingdom, and the University of Miami School of Medicine, Miami, Florida, to compare the use and effectiveness of the service provided., Methods: Data were collected prospectively from inpatients during a 12-month period. The Dermatology Life Quality Index was administered on admission and after discharge. Data were recorded about the diagnosis, duration of admission, and referring dermatologist., Results: In all, 295 patients (Cardiff, UK) and 366 patients (Miami, Fla) participated. The average duration of admission in Miami was 6.7 days compared with 14.2 (P <.0001) in Cardiff. In Miami, the most common reasons necessitating admission were extensive disease (54%), the patient being unwell (18%), photophoresis (14%), outpatient treatment failure (8%), and acute deterioration of disease (4%). In Cardiff, the common reasons were acute deterioration (35%), extensive disease (28%), outpatient treatment failure (22%), and liver biopsy (4%). The most common diagnoses in Cardiff were psoriasis (31%) and eczema (26%). In contrast, the most common diagnoses in Miami, were psoriasis (19%), leg ulcers (17%), and mycosis fungoides (14%). The mean Dermatology Life Quality Index value for all patients decreased after admission in Cardiff (14.9-8.2, P <.0001) and Miami (12.0-8.5, P <.0001)., Conclusion: Despite the differences in the 2 health care systems, inpatient therapy remains an important and effective therapeutic option in the United States and the United Kingdom.

Background: In 1995 the Children's Dermatology Life Quality Index (CDLQI) was developed as a tool to allow quality of life assessment of children with skin conditions. This initial questionnaire was in a written format., Objectives: Using the same validated questions, a full-colour cartoon version has been developed. The aim of this study was to validate this against the initial written questionnaire in a three-part study., Methods: The first part of the study piloted the use of both versions in an outpatient setting. One hundred and one children completed both versions of the CDLQI in a random order. A further 66 children completed the cartoon CDLQI in outpatients, and subsequently completed the cartoon version on the same day at home, which was returned by post. The scores were compared. In the second part, in more controlled conditions to eliminate parental and investigator bias, 107 children with current dermatological problems were administered both versions of the CDLQI in a random order. The scores were analysed, and time to complete each version, and the child and parental preferences, were recorded. The third part assessed compliance by asking 546 children recently reviewed in dermatology clinics to return a single completed postal CDLQI. Half of the children were given the text, and half the cartoon version., Results: The median age of participating children was 11 years. There was no significant difference in scores between the two versions in both parts 1 and 2, but the cartoon version was completed faster (median 90 s) than the written version (median 120 s) (P < 0.0001). Both children and their parents significantly preferred the cartoon version and found it easier to use. Forty-six per cent of the postal CDLQI questionnaires were returned; there was no difference in compliance between the two versions., Conclusions: The cartoon CDLQI is equivalent to the previously validated written CDLQI version, but is faster and easier for children to use, and is preferred by both children and parents.

There is increasing pressure on manufacturers of cosmetic products to provide data to support claims. Data are available from many sources including historical (published literature), laboratory data, cell culture experiments and human studies. Undoubtedly, human studies are the most reliable, and there are a wide range of tests available. Many meters have been developed for measuring different aspects of skin physiology but an understanding of these devices is essential, otherwise the data generated is of little value. There is some confusion as to what exactly some meters measure, an example of which is transepidermal water loss (TEWL) and water content (hydration) of the stratum corneum. Measurement of TEWL is used mainly to support claims that a product may, in the short or long term, improve or repair the barrier function of skin. It is not an indicator of hydration of the stratum corneum. One way to measure hydration is to look for the changes in electrical properties of the stratum corneum that the increased water content produces, i.e. measure capacitance or conductance. It is important that we do not loose sight of the fact that meters may measure something that is imperceptible to the consumer or has no meaning to them. Reliance only on devices that give numbers may lead to problems. An example of a study where three facial cosmetic products were subjected to perceptual tests and to a standard volunteer test for moisturization will be discussed. The relationship between any measured parameter, and what it means to the consumer, needs to be understood. A moisturization claim may be technically supported by a study using a device such as the Corneometer. However, a 20% increase in water content almost certainly does not represent a 20% better moisturization as far as the consumer is concerned. The way forward is to relate the two approaches to product testing during product development. Hopefully, this will allow the product development process to be more systematic.

Two human models were developed to quantify the stratum corneum removed by different adhesive dressings and to measure the peel force of dressing removal and relate this to stratum corneum removal. The first was an open study designed to compare the effects of applying Mepiform Safetac, Tielle and Duoderm Extra Thin to the skin of 12 normal volunteers aged 19-53 years. Treatments were applied once (one 24-hour application) or three times (three x 24-hour applications) to forearm skin which had been prestained with methylene blue. After dressing removal the dye left on the skin was sampled using the skin surface biopsy method and measured spectrophotometrically. The results show that, after one and three applications, the Mepiform Safetac sites had a higher level of dye than those on which the other dressings had been applied (p < 0.05, after three applications). Based on the assumption that the more dye is left on the skin, the less damage is caused, this suggests that Mepiform Safetac is less damaging to the skin surface than the other products tested. In the second study the peel force needed to remove adhesive dressings from prestained skin was measured and related to the amount of stratum corneum removed. Mepilex Border Safetac, Duoderm Extra Thin, Allevyn Adhesive, Biatain Adhesive and Tielle Hydropolymer Dressing were compared in 20 normal volunteers aged 23-64 years. Three consecutive 24-hour applications of each product were made, with measurements of peel force at 24, 48 and 72 hours. The amount of dye remaining on the skin at 72 hours was assessed by the surface biopsy method. Statistically significant differences between products were observed in terms of both peak force and steady state force of removal. Differences in the level of damage to the superficial stratum corneum were also detected. However, low levels of peel force were not always associated with low damage and, therefore, other factors must contribute to stratum corneum removal in this model.

Background: The impact on quality of life (QOL) caused by atopic dermatitis (AD) has been quantified in children and adults using established QOL measures. However, these are not suitable for use in infants under the age of 4 years, when AD usually develops., Objectives: To validate a new parent-generated QOL questionnaire, the Infants' Dermatitis QOL Index (IDQOL), which measures the impact of AD on the infant, and to provide further validation of the Family Dermatitis Index (FDI), which measures the impact of a child's dermatitis on the family., Methods: Parents of 102 predominately caucasian infants under 4 years with AD (34 postal and 68 outpatients) were asked to complete the IDQOL and the FDI on two separate occasions to test for repeat validity. The Infants' Behavioural Check List (BCL) was also given to the study group and to parents of 22 normal control infants. Post-treatment IDQOL and FDI questionnaires were obtained from 25 of the study group., Results: The return rate for initial questionnaires was 87.3% (61 boys, 28 girls) and for retest 70.6%. The mean score for IDQOL was 7.89 and for FDI 8.87. Spearman rank correlation between the IDQOL and FDI was high (r = 0.87). Correlations of IDQOL and FDI with clinical severity assessment by parents were lower (r = 0.58 for IDQOL and r = 0.5 for FDI). Test-retest data for IDQOL and FDI confirmed repeatability, there being negligible differences between the pairs using the method of Bland and Altman. The three highest scoring questions for IDQOL referred to itching and scratching, mood change and sleep disturbance. For the FDI they were parental sleep disturbance, tiredness and exhaustion, and emotional distress. Post-treatment questionnaires from 25 patients indicated sensitivity to clinical change with both IDQOL and FDI. Parameters of behaviour measured using the BCL in 82 study infants and 22 controls showed greater problems with frequent night-time wakening (43% vs. 4.5%) and miserable mood changes (24.4% vs. 9%) in the study infants., Conclusions: Initial validation of the IDQOL and further validation of the FDI show good test-retest repeatability and apparent sensitivity to change with treatment. The effect on health-related QOL as measured by these methods is poorly correlated with clinical severity, confirming that QOL measures should be used in conjunction with clinical measures for global assessments of disease impact. This work requires further validation but suggests that QOL measures may be useful as outcome measures in clinical practice and research. Their simple construction allows quick and easy use, which is particularly valuable in large-scale and postal studies.

Background: Although 75% of skin problems are managed exclusively in primary care, most information on the impact of skin disease on quality of life is hospital based., Objectives: To examine the ease of use of the Dermatology Life Quality Index (DLQI) in primary care and to measure the handicap levels found, analysed by skin disease, sex and age., Methods: The handicap levels identified were compared with those published for patients with the same conditions attending hospital clinics. Some conditions that rarely present in secondary care were also studied., Result: S The overall mean +/- SD DLQI score was 7.37 +/- 5.71 (women 7.8 +/- 5.8, n = 196; men 6.8 +/- 5.6, n = 145). The scores for separate diseases were similar in ranking and only slightly lower than those in hospital-based studies. The possibility of bias towards surveying an unrepresentative sample of patients is discussed. There was no correlation between age and DLQI score., Conclusions: The DLQI proved easy to use in general practice. The impact of skin diseases on the quality of life of patients seen in primary care is comparable with that of patients seen in secondary care. This information could be used to inform the planning of services for these patients.

Human granulocyte-macrophage colony stimulating factor (GM-CSF) is a 22 kD glycoprotein derived from activated T cells, endothelial cells, fibroblasts and macrophages. It stimulates the proliferation and differentiation of haematopoietic cells and certain nonhaematopoietic cells. This study investigated the effect of GM-CSF on cultured human keratinocytes and determined whether these cells express GM-CSF receptors. Measurement of keratinocyte growth by image analysis showed that GM-CSF mildly stimulated the growth of keratinocytes. With 4 ng/ml GM-CSF the growth of primary keratinocytes and subcultured keratinocytes was only stimulated up to 25% and 18% of the control cell level, respectively. Human keratinocytes were incubated with GM-CSF at 4 ng/ml for 4 days to induce receptor expression. These cells showed only a weak positive reaction on affinity labelling using digoxigenated GM-CSF. We conclude that keratinocyte growth may be stimulated by GM-CSF but that the presence of GM-CSF receptors on these cells is equivocal.

One hundred and thirty-seven patients with Darier's disease and 66 patients with Hailey-Hailey disease completed the Dermatology Life Quality Index (DLQI). The average DLQI score for Darier's disease was 5.89 (19.6% of the maximum score), median = 4, quartiles: 1.9. The average DLQI score for Hailey-Hailey disease was 6.06 (20.2% of the maximum score), median = 5, quartiles: 2.9. The DLQI score did not correlate with the physician's assessment of clinical severity in both diseases, thus emphasizing the importance of remembering the potential for handicap even in patients with disease that seems to be mild. The domains of the questionnaire with the highest mean scores in both diseases were for questions relating to symptoms and feelings. Domains relating to personal relationships and work obtained low mean scores even in severe disease. It is encouraging that most patients with Darier's disease and Hailey-Hailey disease maintain good relationships at work and home and seem to be able to adapt to their skin disease.

Fluticasone propionate (FP) 0.05% (CutivateTM) cream is a novel corticosteroid used for the treatment of corticosteroid-responsive dermatoses. To date there are no published data concerning its effect on cutaneous atrophy. This randomized, double-blind study of 40 volunteer subjects was performed to investigate the kinetics of skin thinning induced by topical 0.05% FP cream vs. placebo after once-daily application for 2-8 weeks. The results of this study showed no significant effect on the skin thickness of subjects after 8 weeks' treatment with 0.05% FP cream compared with placebo.

The relationship between clinical findings and antigen profiles in 100 bullous pemphigoid (BP) patients has been investigated. The patients were divided into four groups based upon the results of immunoblot analysis, namely patients whose sera detected the 230-kDa BP antigen (BP230) and the 180-kDa BP antigen (BP180), those recognizing either BP230 or BP180 alone, and those recognizing neither antigen. Analysis by the chi-squared test showed predominant occurrence of oral (P < 0.05) and facial lesions (P < 0.005) in patients whose sera detected BP180, and these patients also tended to have more extensive lesions (P < 0.005). Patients that were positive for BP180 alone needed treatment with higher doses of steroids than the patients positive for BP230 alone (P < 0.05). Furthermore, all five recalcitrant cases, which did not respond well to steroid treatment, were shown to possess autoantibodies against BP180 in their sera. Patients with antibodies to BP230 had a tendency to have a high titre of anti-BMZ antibodies (P < 0.005). These results suggest that anti-BP180 antibodies may be more related to the disease severity than anti-BP230 antibodies. Bullous pemphigoid (BP) is an autoimmune blistering disorder characterized clinically by tense blister formation and immunologically by the presence of tissue-bound and circulating antibasement membrane zone (BMZ) autoantibodies. A number of immunoblot analyses have indicated that two major antigenic proteins of epidermal extracts, the 230-kDa BP antigen (BP230 or BPAG1) and the 180-kDa BP antigen (BP180, BPAG2 or type XVII collagen), are detected by sera from patients with BP in various patterns. Some BP sera recognize both antigen proteins, while others detect only BP230 or BP180 or none. Recently, cDNAs for these antigens have been isolated, and the characteristics for these molecules have been investigated in more detail. The exact relationship between these two proteins is still unclear; however, more recent studies showed that BP180 has an extracellular domain and polyclonal rabbit antibodies raised against an extracellular non-collagenous domain of the murine BP180 antigen were pathogenic in a passive transfer model. Several investigators have suggested a relationship between clinical findings and laboratory data in BP. Arbesman et al. compared the extent and duration of the disease with age, serum levels of IgE, IgA and IgG and titre of anti-BMZ antibodies. The results indicated that serum level of IgE and IgA correlated significantly to the extent of the disease and that titre of anti-BMZ antibodies correlated significantly (only in males) to the duration. There has been only one report which has analysed the relationship between pemphigoid antigens and clinical findings or laboratory data; no correlation was found. In a previous study, the reactivities of BP sera by immunoblotting using human epidermal extracts and two recombinant polypeptides produced from a mouse cDNA clone BPM1 were examined. The results of immunoblotting using epidermal extracts revealed that the two major BP antigens, BP230 and BP180, were detected by 74% and 51% of BP sera, respectively. Comparison of the clinical data with BP antigens gave the impression that the cases whose sera reacted only with BP180 were clinically more severe and less respondent to steroid treatment than the cases which detected BP230 alone on immunoblots. In the study reported here we have examined further the relationship between clinical and immunoblot data by applying a statistical analysis to the results previously obtained.

We have studied the differentiation of ichthyotic epidermis in vitro using the skin equivalent model. The morphology of these ichthyotic cultures has been investigated using histopathological and histometric techniques including epidermal and stratum corneum thickness measurements. The skin equivalents have also been investigated for the presence of markers of differentiation using immunolocalization techniques. These markers include the 65.5 and 67 kDa keratins, desmoplakin, involucrin, laminin and filaggrin. It has been shown that the ichthyotic epidermis develops a fully differentiated epidermis and stratum corneum, equivalent to those seen in normal skin equivalents.

To understand the significance of proteolytic enzymes in the pathogenesis of dermatophyte infections, we have studied the expression of proteolytic activity in vitro. Cultures were extracted after 1, 2, 3, 4 and 5 weeks of growth and the proteolytic activity measured by a peptide release assay using human stratum corneum as a substrate. Maximum activity was noted at 3 weeks which corresponded to the dissolution of the stratum corneum particles. Isolates of Trichophyton mentagrophytes and Trichophyton rubrum from 42 patients with tinea pedis or tinea unguium were established on 2% glucose peptone plates. Using the peptide release assay it was found that after 3 weeks culture, T. mentagrophytes showed higher activity that T. rubrum in tinea pedis (2044 +/- 1067 micrograms protein released h-1 mg-1, n = 13 compared to 828 +/- 614 micrograms protein released h-1 mg-1, n = 13). In tinea unguium, the values at 3 weeks were generally lower. Trichophyton mentagrophytes activity was 837 +/- 121 micrograms protein released h-1 mg-1 (n = 3) compared to 470 +/- 271 micrograms protein released h-1 mg-1 (n = 13) for T. rubrum. Thus, as well as a variation in activity between the two species, there appears to be a variation in site in terms of expression of activity.

1. The cutaneous response to a known irritant has been assessed in human volunteer subjects using both clinical scoring and two non-invasive instrumental methods; erythema measurement using an erythema meter and capillary blood flow using a laser Doppler device. 2. Aqueous solutions (0.5% and 1%) of sodium hydroxide were applied to back skin for 3, 15 and 60 min with assessments immediately after removal and at 1, 24 and 48 hours. 3. Increased erythema was seen with increasing duration of exposure and an increase was also seen at 1 h, 24 h and 48 h after removal of the patch. The results obtained with the erythema meter paralleled the clinical erythema scores. However, the laser Doppler device showed the greatest changes immediately after removal of the patch with subsequent readings showing a gradual decrease. 4. Statistical analysis of the data has been carried out to determine the accuracy and precision of the assessment procedures and to determine the minimum test panel size for detecting irritant reactions. 5. Comparison between back and forearm skin indicated a greater sensitivity to sodium hydroxide on the back. 6. The results of this study define an ethical approach to testing irritant materials in human subjects and provide the basis for the development of a classification system for cutaneous irritants.

A double-blind study has been carried out in 12 normal volunteer subjects in order to determine the relative irritancy of povidone-iodine solutions. Aqueous solutions of 10% povidone-iodine (PI), standardized 10% povidone-iodine (SPI) and reformulated standardized 10% povidone-iodine (RSPI) were applied to the backs and occluded using aluminium chambers. At 1, 2, 3, 4, 5, 6, and 8 hours, chambers were removed and the degree of cutaneous irritancy assessed. As well as subjective assessment of erythema, objective measurement of skin colour was performed using an erythema meter. In addition, laser Doppler blood-flow measurements have been carried out. The results show a rapid increase in cutaneous irritancy as evidenced by an increase in visual scores of erythema, increased erythema meter readings and increased cutaneous blood-flow. The increase was greatest for SPI treated sites for all three methods. Statistically these differences were significant at P < 0.05. Thus in this controlled study it has been possible to discriminate between the similar formulations in terms of their cutaneous irritancy.

The intensity of the cutaneous response was assessed after application of a standard irritant to increasing areas of normal forearm skin. Twenty subjects were tested to determine the minimal irritant dose (MID) to dilutions of aqueous sodium dodecyl sulphate. Each subject was then treated under occlusion for a period of 24 h with different areas of filter paper (9, 25, 100, 225 and 400 mm2) soaked with the concentration required to give the individual's MID. At 25 and 48 h the degree of erythema was assessed using a 0-4 arbitrary scale, a 10-cm visual analogue scale (VAS) and an erythema meter. Cutaneous blood flow was measured with a laser-Doppler device and cutaneous oedema measured by pulsed A-scan ultrasound. The results at 25 and 48 h were almost identical. Both forms of visual assessment (arbitrary scale and VAS) showed an increase in perceived erythema with increasing area and this was confirmed by the erythema meter. Further area-related changes were noted with both cutaneous blood flow and ultrasound measurements.

It has been reported that phenytoin induces gingival and connective tissue hyperplasia and may be of use in wound healing. In this study the effect of phenytoin on human epidermal keratinocytes and skin fibroblasts has been investigated in vitro. Cell cultures were exposed to increasing concentrations of phenytoin from 10(-9) to 10(-4) M in the presence of 1 and 10% serum supplemented medium. In addition the effect of phenytoin on epidermal cell migration (epiboly) has been investigated using organ culture of human skin. No stimulation of cell growth was observed, and only a mild toxicity affecting keratinocytes was seen at the highest concentrations. Similarly, no effect on epidermal cell migration in vitro was observed. The lack of a direct effect in vitro suggests that any in-vivo effect was not the result of interaction between phenytoin and keratinocytes or fibroblasts but possibly due to indirect modulation via other cell types, such as inflammatory or lymphoreticular cells.

Heat shock induces in cells the synthesis of specific proteins called heat-shock proteins. We have compared the induction of these proteins in human keratinocytes, skin fibroblasts, and a human epithelial tumor cell line following exposure to weak and strong inducing agents (heat, cadmium sulphate, and sodium arsenite). The induction of heat shock proteins was measured in cells by one-dimensional gel electrophoresis of [35S] methionine-labeled proteins and by immunofluorescence using a specific HSP72 monoclonal antibody. Both HSP90 and HSP116 were constitutively expressed in these cell types. Exposure of these cells to weak inducing agents such as heat or cadmium sulphate resulted in the synthesis of HSP72 and HSP90, whereas HSP28 and HSP116 synthesis was detected in keratinocytes and fibroblasts following exposure to the strong inducing agent sodium arsenite. In addition, sodium arsenite induced the synthesis of HSP46 in human keratinocytes. Immunofluorescence demonstrated a rapid and reversible accumulation of the 72-kD heat shock protein within the nucleolus of heat-stressed human keratinocytes and fibroblasts.

Double-blind, placebo-controlled studies were performed to assess the effect of 0.1% dimetindene gel on the itch threshold to intracutaneous histamine and on the weal and flare reaction after intracutaneous injection of histamine in normal volunteer subjects. Treatment of the forearm skin in 20 volunteers resulted in an increase in itch threshold with dimetindene gel compared to placebo. Treatment of the forearm skin with dimetindene gel in 32 volunteers had no significant effect on weal thickness in subjects treated for 10, 30 or 60 min, but there was a significant reduction in weal thickness in those subjects treated for 120 min. Topical dimetindene may be of value in treating conditions mediated through histamine release.

In this study we have measured the mean hyphal length as a function of the density of infection in skin surface biopsies from patients suffering from infection with different species of dermatophyte. The tissue response in the epidermis and dermis of these patients was evaluated for the degree of eczematization (epidermal thickening, spongiosis and dermal infiltrate) in periodic acid Schiff stained histological sections, employing visual analogue scales. There was no correlation between mean hyphal density and the degree of eczematization.

The effects of platinum complexes on human fibroblasts and keratinocytes have been investigated. Cytotoxic effects were observed at approximately 4 microM (cisplatin), 10 microM (carboplatin) and 15 microM (JM9) when cells were grown continuously in these agents. When applied topically to hairless mouse skin in vitro carboplatin was shown to penetrate the skin and give levels where a cytotoxic effect would be apparent. Using an in vivo model of epidermal hyperproliferation in the mouse, an antimitotic effect of a 1% and 5% topical carboplatin preparation was demonstrated. These results suggest that topical platinum complexes are of potential in the therapy of hyperproliferative skin diseases.

A three-dimensional reconstruction of living skin-the skin equivalent-has been modified to accept materials that can be applied topically to the skin. Using an irritant gel containing 10% benzoyl peroxide, changes in the skin equivalent model were investigated. Histologically, epidermal necrosis and vacuolar change were observed within 4-6 hr after topical application. Using skin equivalents prelabelled with [(3)H]arachidonic acid, studies involving direct measurement using HPLC and radioimmunoassay have indicated the release of potent lipoxygenase products, such as leukotriene B(4) and 15-hydroxyeicosa-tetraenoic acid. These preliminary results suggest that the skin equivalent may prove to be a useful in vitro model for the prediction of cutaneous toxicity of topically applied substances.

A combination of alkali treatment and proteinase K digestion was used to solubilize nail samples from patients with onychomycosis treated orally with terbinafine. The samples were extracted and the levels of terbinafine and its metabolite measured by high-pressure liquid chromatography. The results showed a relatively rapid penetration of terbinafine into normal nail plate, suggesting that diffusion via the nail plate is the primary route of entry into this tissue. The levels of terbinafine achieved in nail samples exceeded the range of MICs for dermatophytes at the earliest time point (4 weeks) tested in 50% of patients and remained stable, without accumulation, during periods of treatment of up to 3 months.

Immunolocalization studies using the strepavidin/biotin peroxidase system were used to identify epidermal growth factor receptors in 10 samples of normal skin, 13 seborrhoeic warts (SW), five lesions of Bowen's disease (BD), 11 solar keratoses (SK), 22 basal cell carcinomas (BCC) and five squamous cell carcinomas (SCC). The intensity of cell membrane staining was assessed using the 10-cm visual analogue scale technique and the results analysed using non-parametric statistics. The cell membranes in BCC showed significantly less intense staining when compared to normal epidermal cells (P less than 0.001) and the constituent cells of SW (P less than 0.001), SK (P less than 0.001), BD (P less than 0.01), and SCC (P less than 0.001). Classification of the specimens into normal, benign, premalignant and malignant indicated that cell membranes of malignant tumours showed significantly less staining than the other groups (P less than 0.001). The observed reduction in the epidermal growth factor receptors in malignant tumours may be due to occupation and down regulation in response to autocrine secretion of growth factors.

Cyclosporin A has been shown to be effective in the treatment of severe, recalcitrant psoriasis, but it is uncertain whether the mode of action is primarily by immune suppression or by other mechanisms. Cyclosporin-dependent growth-inhibition has recently been demonstrated in vitro using several non-human and transformed epithelial cell lines. In this study the effect of cyclosporin on human epidermal keratinocytes and skin fibroblasts was investigated. Secondary cultures of human epidermal keratinocytes were grown on collagen-coated dishes in the presence of increasing concentrations of cyclosporin. Inhibition of growth was observed at 6-8 microM. An almost identical dose-response curve was obtained for the cytotoxic drug, cis-platin. Short-term exposure (I h) to cyclosporin did not have any effect on epidermal cell growth, suggesting that direct membrane-related effects were not involved. Analysis of cellular proteins by SDS-PAGE indicated no effect of continuous cyclosporin exposure on in vitro differentiation. The observation that human epidermal keratinocyte growth is inhibited by cyclosporin suggests that a topical form of therapy for psoriasis may be an effective alternative to oral treatment.

Exposure of human keratinocytes to non-lethal heat shock treatment (43 degrees C for 90 min) followed by a recovery period of 2 hr at 37 degrees C resulted in the rapid accumulation of two proteins with polypeptide molecular weights of 72 and 90 kDa. Exposure of human keratinocytes to sodium arsenite (10-200 mug/ml) for 90 min at 37 degrees C resulted in the synthesis of proteins with polypeptide molecular weights of 110, 90, 72, 46 and 28 kDa. The 72 kDa heat- or sodium arsenite-induced protein was identified by immunoprecipitation as the 72 kDa heat shock protein. In contrast, the human epithelial tumour cell line (A431) synthesized only the 72 and 28 kDa heat shock proteins in response to arsenite treatment with all other stress proteins being expressed constitutively. General protein synthesis was inhibited in cells exposed to elevated temperature or sodium arsenite. Using immunofluorescence a rapid and reversible accumulation of the 72 kDa heat shock protein was demonstrated within the nucleolus of heat stressed human fibroblasts and keratinocytes.

Detergent substances are important components of cleansing materials. Their detergent cleansing action may also result in skin toxicity. Methods for the evaluation of their toxic effect on the skin surface are reviewed stressing the usefulness of the soap chamber test, and newer in vitro cultural techniques. The action of detergents in promoting desquamation and removing intercorneocyte materials is also discussed. Finally, the point is made that cleansing can also be accomplished with non-detergent containing cleaners.

Although callosities of the plantar skin are common and often disabling, little is known of their pathology or the reasons for their persistence. In this study plantar epidermal structure and cell renewal were investigated in patients with callosities and normal, age-, sex- and site-matched control subjects. Tritiated thymidine autoradiographic labeling indices were increased in the calluses but the dansyl chloride fluorescence clearance time was prolonged, reflecting the increased thickness of the stratum corneum. The number of corneocytes that could be removed from the surface of callosities by a standardized stimulus was considerably increased compared to controls but after adhesive tape stripping no such increase was observed. The density of corneocytes as measured on Percoll gradients was decreased in corneocytes from callus compared to normal plantar skin, and their volume was increased. These observations suggest that there are differences in epidermal differentiation due to an increased rate of epidermal cell production in plantar skin affected by callosity.

The relationship between naturally occurring circulating stratum corneum autoantibodies and experimentally produced antibodies to a non ionic detergent soluble (NIDS) protein fraction from human stratum corneum has been investigated. Using indirect immunofluorescence and indirect haemagglutination techniques, anti NIDS protein serum was shown not to inhibit the autoantibody-antigen reaction. Furthermore no direct interaction could be demonstrated between sheep red blood cells coated with stratum corneum autoantigen and anti NIDS protein serum. The NIDS protein antigens therefore represent a separate and distinct class of stratum corneum antigens.

Nonionic detergent-soluble (NIDS) proteins from human stratum corneum have been prepared by the combined action of detergent and mechanical stimulation of normal human skin. SDS-polyacrylamide gel electrophoresis studies revealed approximately 15 components falling into the molecular weight ranges of 10,000-15,000, 24,000-37,000, and 44,000-68,000. Immunization of rabbits with this material gave antisera which demonstrated 3 or 4 antigenic components using 2-dimensional immunoelectrophoresis. Studies with 125I-labeled NIDS protein indicated that the main precipitate on 2-dimensional immunoelectrophoresis was associated with SDS-polyacrylamide gel components of molecular weight 15,000 and 30,000. Indirect immunofluorescence studies on human skin sections revealed localization of NIDS protein antigens throughout the suprabasal epidermis but concentrated in the stratum granulosum and stratum corneum. Localization studies using strips of stratum corneum obtained by the skin surface biopsy technique revealed a pericellular type of distribution of the NIDS protein antigens.

Fragments of sterile heel callus and suspensions of human corneocytes were implanted or injected intra-cutaneously into flank skin of guinea pigs. A mixed cellular type of inflammation was produced characterized by the accumulation of polymorphonuclear leucocytes in the early stages and a more granulomatous picture in the later stages. Epithelial hypertrophy and follicular distortion with transepidermal elimination was a frequent accompaniment. Immunoglobulins and the complement component C3 were found scattered irregularly in the inflammation produced and were not thought to be important in the process. The inflammation produced closely emulated the changes observed in acne inflammation and after rupture of horn containing cysts. It is suggested that inflammation caused by the implantation of horn may be suitable for study of human skin disease in which horny debris is released into the dermis, such as acne.

There are few methods for assessment of the efficacy of barrier cream preparations that can be used in vivo. This paper describes two such tests. The first relies on the ability of a topically applied barrier preparation to prevent dyes from reaching the stratum corneum from filter paper discs in small aluminium chambers. The amount of dye crossing the barrier cream and reaching the stratum corneum was assessed by removing the superficial layers by skin surface biopsy and eluting out the dye. The second test employed dilutions of sodium hydroxide as indicator reagents. The degree to which these solutions penetrated the barrier on the skin was assessed by measuring the skin blood-flow using the laser Doppler method. It was concluded that both methods could be usefully employed to assess the degree of efficacy of barrier cream preparations.

The fatty acid composition of the skin and plasma lipids is described in a patient severely affected by Refsum's disease whose plasma phytanic acid concentration was very high (3.1 mg/ml). In the epidermal lipids, especially in the phospholipid fraction, phytanic acid tended to replace linoleic acid and to some extent arachidonic acid. In some respects the changes in the skin in Refsum's disease resemble those of essential fatty acid deficiency.

The effect of the concentration of Ca2+ in the medium on the plating efficiency of human epidermal cells has been investigated. Primary cultures plated onto lethally irradiated mouse embryo fibroblasts showed not only increased colony formation at lowered (0.2 mM) Ca2+ levels but also increased growth rate as indicated by greater colony size. On the other hand, secondary cultures showed little variation in plating efficiency and only small differences in colony size were apparent over the range 0.2-1.64 mM Ca2+. Epidermal growth factor had no effect on the Ca2+ dependence of primary or the Ca2+ independence of secondary cultures.

Two brothers are described with ichthyosis, hepatosplenomegaly and signs of cerebellar degeneration. The ichthyosis was similar to autosomal dominant ichthyosis both clinically and biochemically. No metabolic abnormality has yet been identified to account for this previously undescribed triad of abnormalities.

Histamine is liberated in the inflammatory reaction and has been reported to inhibit epidermal cell division in vitro. This study has investigated the effects of histamine and HI and H2 antagonists on epidermopoiesis in vivo in man. No direct stimulatory effect of histamine was detected for normal epidermis. A combination of HI antagonist (chlorpheniramine) and H2 antagonist (cimetidine) led to further increases in epidermal labelling indices in mitotically stimulated epidermis. The administration of HI antagonist alone led to a decrease in mean epidermal thickness. These data suggest that histamine release is unlikely to play a major role in the hyperplasia of inflammatory dermatoses, but that it may be possible to influence epidermal reactions via the HI and H2 receptors.

The in vitro incorporation of 14C acetate by the epidermis has been studied in patients with autosomal dominant ichthyosis and in patients with a dry, itchy, slightly scaly skin associated with a disorder of the small bowel. Analysis of 14C acetate containing lipid moieties by thin layer chromatography has indicated that there are both quantitative and qualitative differences in the uptake of 14C acetate between autosomal dominant ichthyosis and normal. In particular an increased incorporation into the triglyceride and phosphatidyl choline fractions was noted. No such differences were apparent in those patients with disorders of the small bowel. In addition the in vitro incorporation of radioactively labelled thymidine, proline and histidine has been studied in these patients. In both groups of patients the rate of incorporation of tritiated thymidine and histidine into epidermal macromolecules was found not to differ significantly from normal. On the other hand the rate of incorporation of tritiated proline was increased in both groups of patients.

The epidermal metabolic activity of a patient with a marked generalized ichthyosis associated with heredopathia atactica polyneuritiformis has been investigated. Both the in vivo labeling index and the in vitro rates of incorporation of radioactively labeled thymidine, proline, histidine and acetate were increased relative to normal indicating a high rate of epidermopoiesis. Thin-layer chromatographic analysis of 14C-acetate containing lipid extracts revealed qualitative changes compared with normal. In particular, altered proportions of radioactivities were incorporated into the triglyceride and phospholipid moieties. However, as abnormal patterns of lipogenesis are also seen in autosomal dominant ichthyosis, these changes are probably a reflection of disordered keratinization.

Two in vivo techniques which are rapid, inexpensive, and reproducible have been investigated. The first is a standardized radiological (xerographic) technique which we have shown is capable of detecting small degrees of dermal atrophy after the application of topical corticosteroid preparations for only one month. The second technique employs the Harpenden Skinfold Caliper used in an unconventional manner so as to exclude subcutaneous fat. We have shown that this too is capable of detecting dermal atrophy from the application of topical corticosteroids and that there is a strong correlation between the two techniques (r = 0.82, p less than 0.001). Histometric techniques, on the other hand, give inaccurate and erroneous results for dermal thickness.

A female patient with severe Refsum's disease is described. She had striking ichthyosis and detailed investigations into the structure of the epidermis were performed. Light microscopy and transmission electron microscopy revealed lipid-containing vacuoles in the epidermis. Scanning electron microscopy of the stratum corneum showed disruption and the presence of microvilli on individual horn cells consistent with a high output state of epidermal cell production.