Allgemeines,Anatomie, Physiologie,Pathologic

Ohne Zusammenfassung     

Kalk,Muzin, Myxödem,Sklerodermie, Calcinose

Ohne Zusammenfassung     

Titanium: a review on exposure,release, penetration,allergy, epidemiology,and clinical reactivity

Exposure to titanium (Ti) from implants and from personal care products as nanoparticles (NPs) is common. This article reviews exposure sources, ion release, skin penetration, allergenic effects, and diagnostic possibilities. We conclude that human exposure to Ti mainly derives from dental and medical implants, personal care products, and foods. Despite being considered to be highly biocompatible relative to other metals, Ti is released in the presence of biological fluids and tissue, especially under certain circumstances, which seem to be more likely with regard to dental implants. Although most of the studies reviewed have important limitations, Ti seems not to penetrate a competent skin barrier, either as pure Ti, alloy, or as Ti oxide NPs. However, there are some indications of Ti penetration through the oral mucosa. We conclude that patch testing with the available Ti preparations for detection of type IV hypersensitivity is currently inadequate for Ti. Although several other methods for contact allergy detection have been suggested, including lymphocyte stimulation tests, none has yet been generally accepted, and the diagnosis of Ti allergy is therefore still based primarily on clinical evaluation. Reports on clinical allergy and adverse events have rarely been published. Whether this is because of unawareness of possible adverse reactions to this specific metal, difficulties in detection methods, or the metal actually being relatively safe to use, is still unresolved.     

Vitiligo: a comprehensive overview Part I. Introduction, epidemiology, quality of life, diagnosis, differential diagnosis, associations, histopathology, etiology, and work-up

Vitiligo is an acquired pigmentary disorder of unknown etiology that is clinically characterized by the development of white macules related to the selective loss of melanocytes. The prevalence of the disease is around 1% in the United States and in Europe, but ranges from less than 0.1% to greater than 8% worldwide. A recorded predominance of women may reflect their greater willingness to express concern about cosmetically relevant issues. Half of all patients develop the disease before 20 years of age. Onset at an advanced age occurs but is unusual, and should raise concerns about associated diseases, such as thyroid dysfunction, rheumatoid arthritis, diabetes mellitus, and alopecia areata. Generalized vitiligo is the most common clinical presentation and often involves the face and acral regions. The course of the disease is unpredictable and the response to treatment varies. Depigmentation may be the source of severe psychological distress, diminished quality of life, and increased risk of psychiatric morbidity. Part I of this two-part series describes the clinical presentation, histopathologic findings, and various hypotheses for the pathogenesis of vitiligo based on past and current research.