RESUMO
Porphyria is a diverse group of diseases in which the biosynthesis of heme is disrupted by either genetic defects or environmental factors. This review gives an overview of the different types of porphyria and describes possible causes, clinical signs, diagnosis and therapy. In addition, the oral manifestations of porphyria and the potential implications of the disease for dental management are discussed.
Assuntos
Doenças da Boca/etiologia , Porfiria Eritropoética/complicações , Porfirias Hepáticas/complicações , Algoritmos , Anestesia Dentária , Arginina/uso terapêutico , Vesícula/tratamento farmacológico , Vesícula/etiologia , Carboidratos/uso terapêutico , Contraindicações , Heme/biossíntese , Heme/uso terapêutico , Humanos , Doenças da Boca/tratamento farmacológico , Fotofobia/etiologia , Sintase do Porfobilinogênio/deficiência , Porfiria Eritropoética/dietoterapia , Porfiria Eritropoética/tratamento farmacológico , Porfirias Hepáticas/dietoterapia , Porfirias Hepáticas/tratamento farmacológico , Descoloração de Dente/etiologiaRESUMO
Porphyria is a disease of specific enzymes in the biosynthesis of heme, caused by either genetic defects or environmental factors. This review of the literature presents the different types of porphyria and describes their possible causes, clinical signs, diagnosis and therapy. In addition, oral findings observed in patients with porphyria and the potential implications of the disease for dental treatment are discussed.
Assuntos
Assistência Odontológica/métodos , Cárie Dentária/prevenção & controle , Porfirias/complicações , Assistência Odontológica/normas , Cárie Dentária/etiologia , Humanos , Boca/enzimologia , Higiene Bucal , Luz Solar/efeitos adversosRESUMO
Mg2+-induced polymerization of type III intermediate filament proteins vimentin and glial fibrillary acidic protein was studied by transient electric birefringence. In the absence of MgCl2 we found a net permanent dipole moment, approximately 45-nm-long dimers for vimentin, approximately 65-nm-long tetramers, hexamers, and possibly octamers for both proteins, and 100-nm aggregates for glial fibrillary acidic protein. Controlled oligomerization occurred after the addition of MgCl2. Although the solutions contained (small) aggregates of different sizes, more or less discrete steps in polymer formation were observed, and it was possible to discriminate between an increase in width and length. At the first stage of polymerization (in 0.3 mM MgCl2 for vimentin and 0.2 mM MgCl2 for glial fibrillary acidic protein), the permanent dipole moment disappeared without a change in length of the particles. At higher MgCl2 concentrations, structures of approximately 100 nm were formed, which strongly tended to laterally assemble into full-width intermediate filament structures consisting of about 32 monomers. This contrasts with previous models where first full-width (approximately 10-nm) aggregates are formed, which then increase in length. Subsequently, two discrete elongation steps of 35 nm are observed that increase the length to 135 and 170 nm, respectively. Possible structural models are suggested for the polymerization.