RESUMO
BACKGROUND/AIMS: It is often difficult to differentiate between allergic and irritant patch test reactions by visual inspection. The purpose of this study was to test an image analysis-based method that differentiates between the two reactions by quantifying the degree of erythema at the patch test site. METHODS: A total of 172 Japanese patients were patch-tested with sodium lauryl sulfate (SLS) and nickel sulfate, followed by digital photography and visual evaluation of the patch test areas by dermatologists at 48 and 72 h. The digital images were converted to erythema index (EI) images by image processing, and changes in ΔEI (the difference in the EI between the patch test site and the adjacent normal skin) values were analyzed. RESULTS: The ΔEI was significantly increased at 72 h relative to that at 48 h for positive nickel sulfate reactions (P < 0.0001), while no significant difference in the ΔEI was found for SLS reactions. CONCLUSION: Using image analysis, allergic patch test reactions may be distinguished from irritant reactions by evaluating the change in the degree of erythema at 48 and 72 h.
Assuntos
Dermatite Alérgica de Contato/diagnóstico , Dermoscopia/métodos , Interpretação de Imagem Assistida por Computador/métodos , Níquel , Testes do Emplastro/métodos , Dodecilsulfato de Sódio , Alérgenos , Feminino , Humanos , Irritantes , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Circular dichroism in the angular distribution of photoelectrons from SrTiO(3):Nb and Cu(x)Bi(2)Se(3) is investigated by 7-eV laser angle-resolved photoemission spectroscopy. In addition to the well-known node that occurs in the circular dichroism pattern when the incidence plane matches the mirror plane of the crystal, we show that another type of node occurs when the mirror plane of the crystal is vertical to the incidence plane and the electronic state is two-dimensional. The flower-shaped circular dichroism patterns in the angular distribution occurring around the Fermi level of SrTiO(3):Nb and around the Dirac point of Cu(x)Bi(2)Se(3) are explained on equal footings. We point out that the penetration depth of the topological states of Cu(x)Bi(2)Se(3) depends on momentum.
