Robert M. Fine

THE FINE PAGE: THE ORIGIN OF hiv-1

While Strong molecular and epidemiologic evidence has recently been found linking HlV-2 and SiVsm, the precise origin of Hiv-1 has not been definitively established. There are at least three viable hypotheses. First, Hiv-1 may have always been present in the human population and gone unrecognized because of low prevalence or because it was confined to isolated populations or for other as yet unclear reasons. Second, HiV-1 may have been transmitted from another species relatively recently. Third, the virus may have resulted from the recent mutation of a nonvirulent related virus.

THE FINE PAGE: AUTOIMMUNE BASIS FOR CHRONIC IDIOPATHIC URTICARIA

Chronic idiopathic urticaria (ciu) remains the bane of dermatologic practice. Its cause, while dihgently pursued by the patient, physician, and family, usually remains obscure. Few seasoned practitioners claim consistent success in determining its etiology even though exhaustive work-ups, including elaborate questionnaires, elimination diets, extensive diagnostic investigations, including blood tests and x-ray studies, tests for inhalant antigens, etc., are employed and an inordinate amount of time expended in evaluating patients. The list of potential causes is long and traditionally headed by infection, medication, food, and physical agents. Invariably, the patient and/or family is/are convinced that food, usually tomatoes or strawberries in season, seafood, etc. is responsible. Seldom, however, does intentional ingestion of the suspected food consistently provoke a flare or interdiction result in cure. The inability to determine the cause of CIU generates great frustration and at times hostility in patients and a defensive response by their physicians. Many patients are eventually shunted to allergists in desperation, which succeeds in increasing the cost but seldom provides significant benefit to the patient.

THE FINE PAGE: AIDS‐RELATED KAPOSI'S SARCOMA

As the acquired immunodeficiency syndrome (AIDS) epidemic spreads explosively throughout the world, the number of patients with cutaneous manifestations is increasing proportionately. This trend is likely to continue, if not accelerate, in the foreseeable future. The quantity of publications and reports in the academic and lay press is increasing at an exponential rate. It is imperative that dermatologists treating these patients become more knowledgeable about the clinical manifestations, as well as all other aspects of this disease including its pathogenesis. Kaposis sarcoma (KS) is one of the most interesting dermatologic disorders seen in patients with AIDS. Dermatologists have long participated in the diagnosis and management of patients with classic KS. There has been controversy regarding its etiology, pathogenesis, and true nature. Prior to the AIDS epidemic, KS was considered to be an inflammatory or benign proliferative disease that occasionally eventuated in neoplasia or as a low-grade malignancy from inception. A viral etiology had been proposed by some. An interesting and as yet unexplained characteristic of AIDS-related KS is its propensity to affect homosexual men, rather than iv-drug users or hemophiliacs.

The Fine Page Platelet-Derived Growth Factor and Vascular Proliferative Lesions of the Skin

T is growing interest in the role of naturally occurring growth-promoting substances (growth factors [GF]) in the pathogenesis ofvarious inflammatory disorders and tumorigenesis. The recent discovery of the relationship between GF and their receptors and specific oncogenes has heightened this interest. GFs, such as epidermal GF, nerve GF, fibroblast GF, and others have been implicated in the pathogenesis ofvarious dermatologic diseases. Another GF of particular interest to dermatologist is platelet-derived GF (PDGF), which because of its stimulatory effect on fibroblastic, endothelial, and inflammatory cells is thought to play an important role in wound healing. Inflammation and proliferation of vascular smooth muscle cells are features of atherosclerosis, chronic graft rejection, and synovitis. These disorders share certain immunopathologic features, including an increased number of cells bearing the class II histocompatibility antigen HLA-DR and a large number of mononuclear cells and activated macrophages.^ This suggests that PDGF might also play an important role in the induction of vascular proliferative disorders of the skin, such as pyogenic granuloma; hemangiomas; and similar, less well-defined entities. PDGF-like factors are produced in different cells, which include endothelial cells, smooth muscle cells, macrophages, fibroblasts, and various transformed cells. PDGF is stored in platelets and released during blood coagulation.