Epidermal barrier function and systemic diseases.

The skin is a vital organ for life and, among its many functions, the role as a protective barrier is one of the most important. It is the main boundary between the body and the external environment. As defensive barrier, the epidermis protects internal organs from physical and chemical trauma, microorganism invasion, and ultraviolet radiation. It also acts in the regulation of transepidermal movement of water and electrolytes, and in preventing dehydration, all of which are essential for sustaining life. The main role is allotted to the stratum corneum and to the lipid matrix located in the intercellular space. The occurrence of dysfunction in the epidermal barrier is an important factor in the physiopathogenesis of skin diseases, particularly atopic dermatitis and psoriasis. There are few, but important, systemic changes that influence or are influenced by dysfunctions in the epidermal barrier. We review the effects of some systemic diseases on the maintenance of the skin's homeostasis.

Oral involvement in autoimmune bullous diseases.

The oral mucosa is frequently involved by autoimmune bullous diseases and often this is the first site of manifestation. In this site the lesions are very similar, making the clinical diagnosis difficult; therefore, the definition of the immunohistopathologic characteristics of each one becomes essential for a differential diagnosis. The authors review the clinical-pathological and therapeutic aspect of these oral injuries in order to help in the diagnosis, treatment and prognosis of the oral conditions of those diseases.

Premalignant nature of oral and vulval lichen planus: facts and controversies.

Although many classifications include oral lesions of lichen planus in the category of a premalignant condition, there is still much discussion about whether the mucous membranes lesions should be characterized as an intrinsically premalignant condition or merely as a facilitator of the action of a carcinogenic factor. The possibility that an epidermoid carcinoma can emerge at the site of lichen planus lesions, mainly in mucous membranes, has been shown; however, several published cases omit information about other potential risk factors. This prevents a complete analysis of the triggering relationship between lichen planus and squamous cell carcinoma. This contribution reviews the literature on this subject. The question of whether oral or vulval lichen planus, or both, are premalignant conditions will only be answered after prospective studies with large samples and extensive follow-up are performed, taking into consideration the great variety of risk factors involved, together with the establishment of a consensus in relation to the points still without agreement.

Tratamento da alopécia areata: Revisäo bibliográfica de 10 anos / Treatment of alopecia areata: review bibliografic of 10 years

Os autores fazem uma revisäo do tratamento da alopécia areata durante um período de 10 anos e concluem pela näo existência ainda de um medicamento eficaz para curar esta afecçäo