Acne. Current pathophysiologic considerations

Seborrhea, follicular hyperkeratosis, propionibacteria, and inflammatory reactions are the most important factors leading to acne. The combination of increased sebum producation and follicular hyperkeratosis facilitates an increased growth of Propionibacterium acnes. Its metabolic products lead to follicular inflammation and, in extreme cases, even to perifollicular abscesses. Sebum production is influenced by androgens, so that abnormalities in androgen levels can produce seborrhea and acne. Follicular hyperkeratosis may be triggered by a relative deficiency in linoleic acid, peroxides from sebum components, and especially by inflammatory mediators such as interleukin-1. Bacterial metabolic products such as lipases, proteases, or chemotactic factors lead to the perifollicular inflammation. This inflammation is not only a response to other pathogenetic factors, but also a cause of acne. An initial mild perifollicular inflammation can induce comedogenesis via a variety of mediators. The influence of dietary factors on the initiation and course of acne has recently received increased recognition. A connection has been postulated between acne and a high nutrients with glycemic index, as well as with milk products.     

Healing of the surgical wound: I. Basic considerations

Part I of this review explores the basic process by which surgical wounds heal. The relationship of innate physiologic mechanisms of regeneration and repair will be related in part II to the various factors influencing the healing process.     

Chemotherapy: uses and safety considerations.

Topical chemotherapy is used for treating specific skin diseases. Dermatology nurses must understand topical chemotherapy use to minimize exposure for staff and patients.     

Basement membranes: structural and biosynthetic considerations.

Basement membranes are extracellular matrices synthesized by a variety of cells including the basal cells of the epidermis; the respiratory, gastrointestinal, and glandular epithelium; the capillary endothelium; the epithelial cells of the glomerulus, the renal tubule, and the lens capsule; and the endothelium of Descemet's membrane. Basement membranes in the mature animal are free of lipids, DNA, and proteoglycans and are composed of dissimilar protein subunits. One of these is a procollagen-like molecule associated with a noncollagenous matrix glycoprotein. The proportion of the latter component varies among basement membranes. These various subunits are stabilized by hydrogen bonds, disulfide bonds, and aldehyde-derived cross-links which are so extensive that they render the basement membranes highly insoluble. Immunochemical studies indicate three distinct antigenic components which correspond to the collagenous moiety, its nonhelical extension, and the matrix glycoprotein. The collagen component of basement membranes, free of the nonhelical extension, is composed of three identical alpha-chains. It is highly rich in hydroxylysine, 3- and 4-hydroxyproline and contains 4 to 8 residues of half-cystine. It contains 38 residues of glucosyl-galactosyl-hydroxylysine per chain and minimal amounts of mannose, glucosamine, and fucose. Newly synthesized basement membrane collagen is secreted in the extracellular space as the precursor molecule "procollagen." This molecule does not undergo conversion to collagen but interacts with the matrix glycoprotein to give rise to the appropriate structure.     

Observations on syphilis in Addis Ababa. 1. General considerations.

The socioeconomic picture of Addis Ababa, the capital of Ethiopia, is briefly described and the provision of general medical care is outlined. Control of venereal disease is centred on one clinic. Here two doctors attend to nearly 1000 outpatients daily. It is perhaps not surprising that self-diagnosis and self-medication are common and follow-up attendance is erratic.     

Biologic therapeutics in the treatment of psoriasis. Part 2: practical considerations

BACKGROUND: Psoriasis is a chronic inflammatory skin disease principally mediated by activated T cells, which release proinflammatory cytokines with reactive epidermal changes in the skin, producing the characteristic lesions of psoriasis. New research into possible treatment options has been inspired by increased understanding of the pathophysiology of psoriasis and advances in immunology and molecular biology permitting the development of targeted, highly active biologic agents. OBJECTIVE: The aim of this article is to provide practical guidelines for integration of these agents in the management of psoriasis.     

Observations on syphilis in Addis Ababa. 1. General considerations

The socioeconomic picture of Addis Ababa, the capital of Ethiopia, is briefly described and the provision of general medical care is outlined. Control of venereal disease is centred on one clinic. Here two doctors attend to nearly 1000 outpatients daily. It is perhaps not surprising that self-diagnosis and self-medication are common and follow-up attendance is erratic.     

Practical considerations of melanoma/skin cancer screening clinics.

In 1989 a voluntary melanoma/skin cancer screening clinic was held in Oss, the Netherlands. The campaign was carried out according to the free clinics conducted since 1985 in the USA. Our experiences with the first clinic urged us to improve on the organization of the screen. This produced a better yield of the second screen, conducted in 1990 in Arnhem. In this paper we present the practical and organizational implications of melanoma/skin cancer screening based on both screening exercises. It is emphasized that only dermatologists should screen. Concomitant public education will enhance self-selection of people at risk for melanoma/skin cancer. There should be ample provider time, sufficient auxiliary personnel and abundant examination rooms. Total-body skin examination is optional. Follow-up of positive screenees is mandatory. It is concluded that melanoma/skin cancer screening is feasible, particularly in countries with a high dermatologist-to-patient ratio.     

Psychosocial considerations in the management of vitiligo

Vitiligo is a depigmenting skin disease that can carry significant psychosocial impact. Health care providers play a crucial role in shaping patients’ understanding of their condition, approach to treatment, and coping mechanisms. In this contribution, we review the psychosocial aspects of vitiligo management, including the debate over the “disease-ification” of vitiligo, its effects on quality of life and mental health, and methods to holistically assist affected individuals beyond just treatment of the vitiligo itself.