Exploration of a quantitative dansyl chloride technique for measurement of the rate of desquamation

A new fluorescence comparator has been used to measure dansyl chloride-induced fluorescence from the skin surface. By taking readings twice daily, it was possible to ideality a circadian rhythm in which there was relatively depressed desquamation at night, compared with during the day. The study also demonstrated that the rate of desquamution was considerably reduced from protected sites, compared with normal unprotected sites. Other experiments demonstrated the ability of the technique to determine the enhanced rate of desquamation from uninvolved areas of skin near lesions of psoriasis, and the keratolvtic effect of preparations containing salicylic acid. It is considered that the technique adds objectivity and quantitative ability to the dansyl chloride method for characterizing desquamation.     

The effects of an abrasive agent on normal skin and on photoaged skin in comparison with topical tretinoin

Two studies were designed to assess the effect of abrasive preparations on the skin and to test the specificity of the effect of topical tretinoin in the management of chronic photodamage to the skin. In the first study two abrasive preparations (Brasivol fine and Brasivol medium) were compared with white soft paraffin and no treatment in eight volunteer subjects for their effects on the epidermis. The study was conducted over 3 days and measurements were taken of the effects on dansyl chloride-induced fluorescence to assess desquamation, epidermal thickness, and the tritiated thymidine autoradiographic labelling index. The abrasives were found to increase the desquamation rate significantly and to increase epidermal thickness and the epidermal labelling index compared to white soft paraffin and no treatment. In the second study the effect of one of the abrasive preparations (Brasivol medium) was compared with 0.05% tretinoin cream (Retin A) on the photodamaged skin of the dorsal aspects of the forearms of 12 subjects over an 8-week period. Cutaneous blood flow measured by the laser-Doppler flowmeter was found to be significantly increased in the abrasive-treated sites, but there was only a non-significant trend to increased blood flow in the tretinoin-treated sites. Measurements of skin thickness using pulsed A-scan ultrasound demonstrated that both treatments produced significant increases in thickness over the 8-week period but the increase was greater for the abrasive treated site. Measurements of the skin extensibility at the treated sites were made using a uniaxial extensometer. Forces needed for 30% skin extension were increased in the abrasive-treated sites only. Measurements of epidermal thickness and of [3H]-thymidine autoradiographic labelling indices showed greater increases in the abrasive-treated sites than in tretinoin-treated sites compared to untreated sites, but these increases were not statistically significant. No significant inflammation and no changes in the degree of elastosis or the presence of a 'repair zone' were found in any of the post-treatment biopsies. The results indicate that some of the changes produced in the skin by topical tretinoin that are taken to indicate a specific antiphotoageing effect may not in fact be specific and can be achieved by an abrasive preparation.     

The role of ascorbic acid on collagen structure and levels of serum interleukin-6 and tumour necrosis factor-alpha in experimental lathyrism

Lathyrism is characterized by defective collagen synthesis due to inhibition of lysyl oxidase, an enzyme essential for interfibrillar cross-linking. The lathyritic agent beta-aminoproprionitrile (beta-APN) is considered an appropriate agent for studying connective tissue metabolism. We investigated the effects of ascorbic acid on collagen structure and serum cytokine levels in experimentally induced lathyrism. Forty Wistar rats weighing 200-300 g were used in the study: three test groups of 10 rats each (groups 2, 3 and 4) and 10 rats used as a control group (group 1). Experimental lathyrism was induced with daily subcutaneous injections of beta-APN in the test groups for 40 days. On the 40th day, skin biopsies were taken from the control group (group 1) and group 2, to evaluate the effect of beta-APN on dermal collagen. After the 40th day, 10 rats received ascorbic acid 100 mg/kg intraperitoneally daily for 15 days (group 3) and 10 rats (group 4) received no medication and served as a control for group 3. On the 55th day, skin biopsies were taken from groups 3 and 4. Serum concentrations of interleukin-6 and tumour necrosis factor-alpha were assessed in each group by enzyme-linked immunosorbent assay. Ultrastructural examination of the skin biopsies in group 1 revealed normal-appearing epidermal and dermal structures. Group 2 showed disorganization of the epidermis and collagen structure, and vacuolization of the endoplasmic reticulum in fibroblasts. In group 3, ultrastructural examination revealed significant improvement in the structure of dermal collagen after administration of ascorbic acid, whereas the changes in group 4 were unremarkable. Ascorbic acid administration significantly decreased the concentrations of serum cytokines in group 3 compared with group 2 (P < 0.001). Ascorbic acid administration significantly improved dermal collagen structure and serum cytokine levels in experimental lathyrism.     

Detection of the action of salicylic acid on the normal stratum corneum

The undoubted clinical usefulness of salicylic acid contrasts markedly with its barely detectable action on normal skin. In this study we have attempted to extend our understanding of the action of salicylic acid by monitoring its effect on the stratum corneum using newly developed techniques for assessing desquamation, as well as using conventional methods for measuring other aspects of epidermal activity. Our findings have succeeded in demonstrating that salicylic acid enhances the shedding of corneocytes and we suggest that this compound in some way decreases corneocyte to corneocyte cohesion. We have confirmed that salicylic acid has no effect on the mitotic activity of the normal epidermis.     

Quantification of microvascular changes in the skin in patients with psoriasis

It has been suggested that there is a widespread abnormality of the capillaries in the skin of patients with psoriasis. This study was carried out to obtain more evidence on this point. Lesions of 20 patients with typical psoriasis, and uninvolved skin 3 cm from these lesions, were biopsied and compared with biopsies from 10 normal healthy control subjects. The dermal microvasculature was quantified in all these biopsies with regard to endothelial and luminal volume relative to the volume of dermal components of skin using stereological point counting methods utilizing the Delesse principle. The values for endothelial volume in specimens taken from the centre of the lesions did not differ significantly from those taken from the margins (33.6 x 10(-3) and 35.8 x 10(-3), respectively). The same was true for the luminal volume from the two sites (9.1 x 10(-3) and 10.0 x 10(-3), respectively). There was a highly significant difference, however, between the value for endothelial volume in biopsies from psoriatic patients compared to controls (P less than 0.001) and specimens from uninvolved psoriatic skin also showed a highly significant difference (P less than 0.001) from involved areas. There was no significant difference between uninvolved areas in psoriasis patients and control specimens. Significant differences were also found between values for control subjects and those for both involved and uninvolved psoriatic skin for luminal volume (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

腹部复发性疼痛性红斑一例

患者,女,72岁。腹部皮肤反复起红斑伴疼痛11年。皮肤科查体：腹部片状红斑及黄褐色色素沉着斑,境界清楚,表面稍粗糙,无脱屑、糜烂、渗出,皮损之间可见正常皮肤,皮温稍高,有明显触痛及摩擦痛。组织病理示：表皮轻度角化过度,局灶增厚伴上皮脚延长、融合,基底层色素颗粒增多,真皮浅层血管旁见少许淋巴细胞浸润。诊断：复发性疼痛性红斑。     

The ribonucleic acid (RNA) skin test in systemic lupus erythematosus and other connective tissue diseases

A series of 65 patients with different autoimmune diseases was examined using different RNA-solutions for intradermal skin tests. Clinically positive results were obtained most often in patients with mixed connective tissue disease but quite often also in patients with systemic lupus erythematosus and progressive systemic sclerosis or with some symptoms of an automimmune nature. The histological examination of the biopsies from the test sites revealed that there was no correlation between the clinically positive tests and the histological criteria usually used as a sign of a positive test.     

The induction of ornithine decarboxylase in human epidermis is independent of lipoxygenase and cyclo-oxygenase pathways.

In vivo studies in rodents suggest that prostaglandins and/or leukotrienes are involved in the epidermal induction of ornithine decarboxylase (ODC). Recently, we have shown that, in human epidermis, prostaglandins are not involved in this process. Here we report the role of leukotrienes in epidermal ODC induction in human skin. Topical flufenamic acid (Dignodolin), vehicle, or nothing was applied under plastic occlusion to three sites on the backs of healthy volunteers. This was followed 1 h later by Sellotape stripping. After renewed application and occlusion for 8 h, biopsies were carried out for the estimation of ODC levels. There were no significant differences in the levels of ODC between the flufenamic acid treated and control sites. To confirm this finding, test sites were irradiated with 3 MED of UVB. This was immediately followed by the application of flufenamic acid, vehicle, or nothing to the three irradiated sites. After 8 h, biopsies were taken, and the levels of ODC were again similar in the flufenamic acid- and the vehicle-treated sites. The data indicate that, following Sellotape stripping or UVB irradiation, neither lipoxygenase not cyclooxygenase products contribute to the in vivo induction of ODC in human epidermis.     

Studies of the clinically uninvolved skin in patients with dermatitis

We have studied the clinically normal skin of eighty-four patients with quiescent dermatitis of different types, and fifty normal subjects. Increased susceptibility to chemical irritation was demonstrated in patients with atopic and exogenous dermatitis. There was a reduction in mean corneocyte area and a thinner horny layer in all patients, and an increased epidermal thickness in atopic dermatitis patients only. In forced desquamation studies, patients released more corneocyte clumps from the skin surface, but there were no significant differences between patients and controls in sensitivity to UVR or electrical conductivity.     

Percutaneous absorption of salicylic acid in man after topical administration of three different formulations

OBJECTIVE: To determine the amount of drug which is absorbed during 1 day following topical application of three different preparations containing salicylic acid. METHODS: Ten grams of the formulations, either (a) Kerasaltrade mark 5% ointment, (b) salicylic acid 5% or (c) 10% in petrolatum, were administered consecutively to a 600-cm2 area on alternating sides of the back of healthy volunteers (n = 9). Thirty minutes after application, a skin area of 2.54 cm2 was stripped with D-Squametrade mark adhesive disks to determine the amount of salicylic acid in the stratum corneum. The entire application site was then covered by a thin gauze bandage and was not washed for the next 24 h. Urine was collected for 26 h following administration, hydrolyzed and assayed by HPLC analysis. RESULTS: The absolute amounts absorbed and excreted were 52.6 +/- 29.4 mg (mean +/- SD), 127.1 +/- 43.9 mg and 208.0 +/- 81.7 mg, and the doses absorbed in relation to the doses applied (500 mg salicylic acid in case of formulations a and b and 1,000 mg for formulation c) were 9.3 +/- 3.8, 25.1 +/- 8.5 and 20.2 +/- 7.7%, respectively. The amounts of salicylic acid in the skin 30 min after application were 36.3 +/- 16.5, 18.2 +/- 11.9 and 31.3 +/- 15.4 microg/ cm2 as determined by the tape stripping procedure. CONCLUSIONS: Significant differences in the doses absorbed were detected between the two formulations a and b (same concentration) with different vehicles (p value < 0.001) as well as between b and c (same vehicle) with different concentrations (p value = 0.018) using Student's paired t test. These results demonstrate that salicylic acid is well absorbed by healthy skin.     

Development of an in vivo animal model for skin penetration in hairless rats assessed by mass balance

The aim of the study was to develop an in vivo animal model for studies of the penetration of topically applied drugs into the skin of hairless rats. Protective appliances were designed for non-occluded and finite-dose application of topical formulations. The design allowed 2 test sites for each rat and free mobility throughout the test period. By consecutive tape stripping, monitored by measurements of transepidermal water loss and confirmed by histological examination of skin biopsies, 10 tape strippings were found to remove the stratum corneum completely. For assessment of the model, (14)C-salicylic acid and (14)C-butyl salicylate were topically applied. Rapid and differentiated percutaneous absorption of both compounds were shown by urinary excretion data. For (14)C-salicylic acid the amount on the skin surface, in the stratum corneum and in the viable skin was determined. Total mass balance on the applied radioactivity was performed and a recovery of 90 +/- 2% was achieved. The radioactivity found in the protective appliances (<10%) was explained by lateral skin diffusion of the model compounds into the dressings.     

Differential effects of sodium lauryl sulphate and non-anoic acid on the expression of CD1a and ICAM-1 in human epidermis.

Normal human skin was exposed to two different detergents, sodium lauryl sulphate in distilled water and non-anoic acid in isopropanol at different concentrations. The detergents were applied under occlusion in epicutaneous tests for 24 h and biopsies were taken at 24 or 48 h. Frozen sections were labelled with monoclonal antibodies against CD1a, CD3 and ICAM-1. The evaluation of the labelled sections showed that there were differential effects on the expression of ICAM-1 and CD1a+ cells in epidermis. After non-anoic acid application ICAM-reactivity could not be detected and there was a decrease of staining for CD1a after exposure to 80% non-anoic acid. Sodium lauryl sulphate treatment, however, induced ICAM-1 expression on keratinocytes and had minor effects on the number of CD1a+ cells. ICAM-1 expression was also detected in normal epidermis in 3 of 9 unexposed control biopsies and after occlusion with the vehicles distilled water and isopropanol. An increased amount of CD3+ cells was found in the skin exposed to both detergents. The results show that there are dose and time dependent variations in the epidermal response to irritants which might influence the immunological events taken place in the epidermis.     

Rosacea: a clinicopathological approach

BACKGROUND: There are few reports of the histological changes in rosacea, and little attempt has been made to correlate such changes with clinical findings. In the present study, we describe in detail the histopathological features of rosacea in a large number of patients and simultaneously investigate the aetiopathogenesis of the disease based on the comparative assessment of epidemiological, clinical and histological findings. METHODS: The study included 73 patients with rosacea. A skin biopsy with a 4-mm punch was performed in each case. All biopsy specimens included subcutaneous tissue. In 10 randomly selected patients, facial biopsy specimens were obtained from both involved and uninvolved (non-lesional) skin. Demodex mite presence was estimated semi-quantitatively under light microscopy. Patients with self-reported gastro-intestinal symptoms were submitted to upper gastro-intestinal endoscopy, and a rapid urease test was performed. Serological antibodies, IgG and IgA, against Helicobacter pylori were also detected. RESULTS: The patients had a broad clinical spectrum of lesions. No specific histological features associated with either erythematous-telangiectatic or papulopustular clinical forms were noticed. Histological examination showed that there is no histological pattern unique to rosacea. Three different types of granulomas were observed: small palisaded ones around altered collagen and other granulomas of elastolytic and non-specific epithelioid type, all coexisting in 5 cases. The deep dermis and subcutis were frequently involved. Comparative study in 10 rosacea patients between lesional and non-lesional skin biopsies revealed almost the same histological changes to the latter biopsies, to a lesser degree though. CONCLUSION: Rosacea seems to be a reaction pattern to which a variety of pathogenetic routes may lead.     

维A酸衍生物ECPIRM对维A酸核受体的影响及小鼠皮肤刺激反应

目的 探讨维A酸衍生物ECPIRM对维A酸核受体的影响,评估ECPIRM对小鼠皮肤的红斑、脱屑等刺激反应.方法 10μmol/L ECPIRM和全反式维A酸(ATRA)作用于SCL-1细胞24 h,用蛋白免疫印迹法和实时荧光定量PCR法分别检测维A酸受体(RARα 、RARβ、RARγ和RXRα)的蛋白和mRNA表达变化.用实时荧光定量PCR检测维A酸受体RAR激活通路的靶基因细胞色素P450家族成员26A1和他扎罗汀诱导基因1 (TIG1)的mRNA表达变化.BALB/c小鼠剃毛后外涂ECPIRM凝胶,以等摩尔浓度的全反式维A酸乳膏为对照,观察小鼠皮肤刺激反应.结果 ATRA作用后,RARα、RARβ、RARγ的蛋白和mRNA表达明显增高,与对照组比较差异有统计学意义(P＜0.05).CYP26A1和TIG1的mRNA表达分别增加到25.49倍和3.88倍,差异有统计学意义(P＜0.01).但ECPIRM作用后并不增加核受体RARα、RARβ、RARγ及RXRα的蛋白表达;RARα、RARβ、RARγ的mRNA表达变化差异无统计学意义(P＞0.05);RAR靶基因CYP26A1和TIG1的mRNA表达变化差异无统计学意义(P＞0.05).BALB/c小鼠外用全反式维A酸乳膏后2d出现明显的红斑、脱屑反应,用药5d达高峰.而连续外用0.075％ECPIRM凝胶21d,小鼠一直未出现红斑、脱屑反应.结论 ECPIRM不激活经典的维A酸受体通路,未出现ATRA样皮肤刺激反应.     

''Decubital candidosis'': a study of 26 cases

BACKGROUND: Candidoses are infections caused by yeasts of the genus Candida. 'Decubital candidosis' is a particular form of cutaneous candidosis that occurs on the dorsal skin of chronically bedridden patients; there are very few studies about this presentation in the medical literature. OBJECTIVE: To study the clinical, mycological and histopathological features of 26 cases of 'decubital candidosis' along with factors that may predispose to it. METHODS: Twenty-six patients were included and their general characteristics and clinical lesions were carefully studied. The presence of candidosis in other organs and the occurrence of predisposing factors were searched by reviewing the medical records. Mycological studies were performed and cutaneous biopsies were taken. RESULTS: Median age of patients was 46 years, 11 were male and 15 were female, 25 were caucasian, one was Asian and no one was Afro-Carribean. This finding suggests a greater resistance of Afro-Carribean skin to this form of candidosis. The median time of hospitalization until rash occurrence was 24.8 days. Clinical lesions consisted of erythema, erosions, pustules, papules and desquamation. The most significant predisposing factors for this eruption were prolonged bedrest and broad-spectrum antibiotics. Candidosis on other body sites was diagnosed in 10 cases and additional specific predisposing factors were observed in all 10. Potassium hydroxide examination was a reliable test for diagnosing this disease. Candida albicans was the agent in all 26 cases. Spongiform pustules were the most significant histopathological findings and yeasts were restricted to the horny layer in all biopsied cases. CONCLUSION: 'Decubital candidosis' is probably induced by prolonged bedrest and facilitated by long-term use of antibiotics. This cutaneous infection does not seem to predispose to systemic candidosis.     

Skin response to histamine dry skin prick test: influence of duration of the skin prick on clinical parameters and on skin blood flow monitoring

This comparative trial (histamine dry skin prick test versus control prick test) evaluates with subjective and objective clinical methods (i.e. itch scores, wheal area, and wheal and flare area) and with laser Doppler flowmetry (multiple sites measured between 5 and 15 min after prick test) the effect of increasing the duration of the skin prick (1, 3 and 10 s). As compared with control prick tests, all objective clinical parameters after histamine prick test were significantly different from the control prick tests. There was no interaction between agonist-duration of prick test and clinical parameters. When present, itch was reported only after histamine prick test. Skin blood perfusion values were evaluated with Laser Doppler flowmetry at prick test sites and at 1 cm distance from the prick test site. At control and histamine prick test sites, increased blood flow values were observed and a moderate interaction between agonist-duration of prick test and repeated measurement was noted (one tail P less than 0.05); there were indeed lower values 9 min after histamine prick tests whatever the duration of the prick test. At 1 cm distance from histamine prick test sites, all skin perfusion measurements (either 5-8 or 11-14 min) showed increased values over data recorded after control prick test (P less than 0.0001). On pooled data recorded at distance from histamine or control prick tests, there was a significant interaction between agonist-duration of prick test and laser Doppler flowmetry (P less than 0.0004).(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of topical petrolatum and salicylic acid on the erythemogenicity of UVB

Various topical agents used in combination with phototherapy have blocking effects, however in contrast to in vitro studies there were not enough in vivo studies about this subject. Our purpose was to examine the photoprotective effects of white petrolatum and salicylic acid which can be used before UVB therapy in psoriasis patients. In 35 volunteers, a phototest was performed to determine the minimal erythema dose (MED) and the test was repeated with thin (0.1 cc/25 cm2) and thick (0.3 cc/25 cm2) petrolatum, thin and thick salicylic acid (20%) in petrolatum and sunscreen. After 24 hrs, the effects of each agent on MED was investigated. MED values detected after pure UVB and after application of topical agents were compared one by one, and the differences between all of them have been found statistically significant. These showed that MED values were increased by thin or thick petrolatum and also by thin and thick salicylic acid (20%) in petrolatum. The highest MED values were detected with thick salicylic acid in petrolatum followed by thin salicylic acid in petrolatum, thick petrolatum and thin petrolatum. The application of petrolatum and salicylic acid, which can block UVB, before phototherapy is not recommended.     

The investigation of superficial fungal infections by skin surface biopsy

The skin surface biopsy technique using a cyanoacrylate contact cement was employed for the diagnosis and study of superficial mycoses. The biopsy specimens were used for quick direct examination after treatment with potassium hydroxide and blue-black ink, direct examination after staining with the periodic-acid Schiff method, fungal culture and scanning electron microscopy. Skin surface biopsies were taken from 124 patients for one or more of these purposes. Direct examination and culture of the specimens proved simple, and reliable for diagnostic use in clinical practice. In addition, the morphology of the infective agent could easily be studied in detail in its in vivo arrangement in the intact sheets of horny layer, either in stained preparations or under the scanning electron microscope.     

Moisturizing cream ameliorates dryness and desquamation in participants not receiving topical psoriasis treatment

Psoriasis is a disorder characterized by faster than normal skin growth, resulting in a buildup of thickened areas with a scaly appearance. Common sites of involvement include the scalp, elbows, knees, and back. Moisturization of these areas may provide relief by increasing hydration. Accordingly, the use of a moisturizing cream (Cetaphil Moisturizing Cream) was studied in participants with mild to moderate plaque psoriasis (5%-10% body surface area) who either were not being treated or had discontinued the use of all topical psoriasis medications and all other moisturizers and remained off of them for the entire study. The condition of the participants'skin was objectively monitored for skin barrier function through transepidermal water loss (TEWL), skin hydration through corneometry, and desquamation through the use of sticky tape corneocyte counts (D-SQUAME). Thirty participants were enrolled. The results of this 4-week study indicate there was no further damage to the skin barrier, as no significant change in TEWL was seen. Furthermore, skin hydration increased over the course of the study. Desquamation measurements showed a significant percentage of participants with skin improvements from very dry to dry or normal (P < .0001 for all time points). All of these effects were noted despite the absence of topical psoriasis treatment. The investigator assessed that this moisturizer was well-tolerated and appropriate for use on the damaged skin of participants with psoriasis.