a b s t r a c tBacterial cellulose (BC) is a highly pure form of cellulose, produced in the form of a swollen membrane by several bacteria that demonstrated to be able to modulate the skin release of model drugs. In the present study, the skin irritation potential of BC was evaluated in human subjects. BC membranes with and without glycerin (acting as plasticizer) were tested. No significant differences were observed for transepidermal water loss (TEWL) measurements in comparison with negative control, 2 and 24 h after patch removal, which is an indicator of an absence of barrier disruption. Similar results were found for erythema. Clinical scores were zero at both times for all volunteers, with the exception of five volunteers that exhibited weak reactions. BC with glycerin provided a skin moisturizing effect statistically higher than the negative control (p = 0.044), which was not observed for BC alone. The good skin tolerance found after a single application under occlusion reinforces the putative interest of BC membranes as supports for drug topical delivery. Besides modifying the mechanical properties, the inclusion of glycerin results in a skin moisturizing effect which could be clinically relevant for the treatment for skin diseases characterized by dryness, such as psoriasis and atopic dermatitis.

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Topical application of natural antioxidants has proven to be effective in protecting the skin against ultravioletmediated oxidative damage and provides a straightforward way to strengthen the endogenous protection system. However, natural products can provoke skin adverse effects, such as allergic and irritant contact dermatitis. Skin irritation potential of Castanea sativa leaf ethanol:water (7:3) extract was investigated by performing an in vivo patch test in 20 volunteers. Before performing the irritation test, the selection of the solvent and extraction method was guided by the 1,1-diphenyl-2-picryl hydrazyl (DPPH) free radical scavenging test and polyphenols extraction (measured by the Folin Ciocalteu assay). Iron-chelating activity and the phenolic composition (high performance liquid chromatography/diode array detection) were evaluated for the extract obtained under optimized conditions. The extraction method adopted consisted in 5 short extractions (10 min.) with ethanol:water (7:3), performed at 40 ° . The IC 50 found for the iron chelation and DPPH scavenging assays were 132.94 ± 9.72 and 12.58 ± 0.54 μ g/ml (mean ± S.E.M.), respectively. The total phenolic content was found to be 283.8 ± 8.74 mg GAE/g extract (mean ± S.E.M.). Five phenolic compounds were identified in the extract, namely, chlorogenic acid, ellagic acid, rutin, isoquercitrin and hyperoside. The patch test carried out showed that, with respect to irritant effects, this extract can be regarded as safe for topical application.Many plant extracts are used in cosmetic formulations as additives (fragrances, colorants, etc.) or are used due to their functional properties (emollient, anti-irritant, moisturizing, slimming, anti-ageing, etc.). Botanical products are also used in topical pharmaceutical preparations in a wide variety of skin disorders. However, allergic and irritant contact dermatitis and phytophotodermatitis are included among the topical adverse effects of natural products [1]. Members of the Ranunculaceae, Euphorbiaceae and Asteraceae (Compositae) plant families are specially involved in irritant contact dermatitis. Phytophotodermatitis is caused by plants containing furocoumarins, which notably include the members of the Umbelifereae, Rutaceae and Moraceae plant families. Allergic contact dermatitis is induced primarily by plants from the Asteraceae family, which contain sesquiterpene lactones, but other families containing this class of compounds, specially the Lauraceae, Magnoliaceae and Jubulaceae families, can also produce allergic reactions. Besides studying the activity of plant extracts, suitable tolerance studies are therefore required before any possible practical application.The skin is exposed to a broad variety of biological, chemical and physical attacks. Among them is solar ultraviolet (UV) radiation that is responsible for skin damage, which includes erythema, photoageing and cancer. Following UV exposure, reactive oxygen species (ROS) are produced and are believed to be largely responsible for some o...

Case 1  A 42‐year‐old married man reported heterosexual behavior with multiple partners, chronic alcoholism, and a previous history of urethritis. He presented with a 1‐year history of two asymptomatic, erythematous to violaceous, annular or polycyclic plaques, involving the anterior aspect of the left thigh. The lesions had raised, well‐defined, infiltrated borders, with irregular crusted ulcers at the periphery, and there was central healing with atrophy (Fig. 1). Histologic examination of a skin biopsy specimen showed lymphocytes and plasma cells infiltrating the superficial and deep dermis, and epithelioid granulomas. Warthin–Starry stain for spirochetes was negative. Venereal Disease Research Laboratory (VDRL) test was reactive (1 : 64) and Treponema pallidum hemagglutination assay (TPHA) was positive. Tests for hepatitis B, hepatitis C, human immunodeficiency virus‐1 (HIV‐1), and HIV‐2 were negative. Neurologic examination revealed changes attributable to chronic alcoholism. VDRL test and TPHA of cerebrospinal fluid were negative. Echocardiogram showed moderate dilatation of the ascending aorta, thickening of the aortic valves, and moderate aortic insufficiency. The patient received 2.4 million units of benzathine penicillin G, intramuscularly, once per week for three consecutive weeks, with rapid resolution of the lesions. His wife had a nonreactive VDRL test and positive TPHA, and was treated with the same regimen. 1 Erythematous to violaceous plaque, with crusted and ulcerated border, on the left thigh Case 2  A 32‐year‐old married woman of rural background and residence presented with a 1‐year history of occasionally pruritic, papulonodular lesions, involving the presternal (Fig. 2) and left eyebrow (Fig. 3) regions, papules in a polycyclic configuration, and clusters of erythematous, infiltrated nodules, some of which showed ulceration with a surface crust. There was central atrophy and noncontractile scarring. Her husband had been treated for primary syphilis approximately 5 years earlier with benzathine penicillin G; however, the wife was not notified and therefore was not treated. Histologic examination of a presternal lesion revealed erosion and acanthosis with irregular papillomatosis of the epidermis, a dense superficial dermal infiltrate of lymphocytes, plasma cells, and epithelioid cells, and granulomas with multinucleated giant cells. Warthin–Starry stain was negative. VDRL test was reactive (1 : 128) and TPHA was positive. Serology for hepatitis B and C and for HIV‐1 and HIV‐2 was negative. VDRL and TPHA analyses of the cerebrospinal fluid were negative. The patient was treated with 2.4 million units of benzathine penicillin G, intramuscularly, once per week for 3 weeks, with rapid resolution of the lesions. One year after treatment, there was slight central, noncontractile atrophy and peripheral hyperpigmentation (Fig. 4). 2 Clustered, infiltrated nodules, with crusted surfaces and central atrophic scarring, in the presternal region 3 Infiltrated nodules with crusted surfaces on the ...

This study concerns a 69-year-old female patient with a longstanding history of venous ulcerations on both lower legs and multiple sensitivities, who developed eczematous lesions with the hydrocolloid dressing Combiderm1 (Convatec Ltd., a Bristol-Myers Squibb division, Ickenham, Middlesex, UK). Epicutaneous tests were positive to this dressing and to a modified colophonium derivative, i.e. glyceryl rosinate, however not to the unmodified colophonium from the standard series. A review of the literature showed several case reports about sensitization to similar hydrocolloids being distributed under various brand names in different countries and which contain the pentaerythritol ester of the hydrogenated rosin as the tackifying agent. Some of the patients described did, while others did not, react to colophonium but only to a modified derivative. In our patient, the reaction to glyceryl rosinate most probably represent cross-sensitivity with the modified colophonium derivative used in Combiderm1, the presence (but not the exact nature) of which was showed by the company. In patients where allergic contact dermatitis from hydrocolloid dressings is strongly suspected and colophonium tests negatively, patch testing to modified colophonium derivatives should therefore be performed. As the complete composition of wound dressings is most often unknown, we urgently advocate legal requirements for labelling of those and in fact all medically used devices.