RESUMO
OBJECTIVE: To compare and quantify the retinal vascular changes induced by non-intentional pressure contact by digital handheld camera during retinopathy of prematurity (ROP) imaging by means of a computer-based image analysis system, Retinal Image multiScale Analysis. METHODS: A set of 10 wide-angle retinal pairs of photographs per patient, who underwent routine ROP examinations, was measured. Vascular trees were matched between 'compression artifact' (absence of the vascular column at the optic nerve) and 'not compression artifact' conditions. Parameters were analyzed using a two-level linear model for each individual parameter for arterioles and venules separately: integrated curvature (IC), diameter (d), and tortuosity index (TI). RESULTS: Images affected with compression artifact showed significant vascular d (P<0.01) changes in both arteries and veins, as well as in artery IC (P<0.05). Vascular TI remained unchanged in both groups. CONCLUSIONS: Non-adverted corneal pressure with the RetCam lens could compress and decrease intra-arterial diameter or even collapse retinal vessels. Careful attention to technique is essential to avoid absence of the arterial blood column at the optic nerve head that is indicative of increased pressure during imaging.
Assuntos
Competência Clínica , Diagnóstico por Computador/efeitos adversos , Processamento de Imagem Assistida por Computador , Disco Óptico/patologia , Artéria Retiniana/patologia , Retinopatia da Prematuridade/patologia , Competência Clínica/estatística & dados numéricos , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Disco Óptico/fisiopatologia , Fotografação , Artéria Retiniana/fisiopatologia , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/fisiopatologia , TelemedicinaRESUMO
Shigella boydii, Shigella flexneri, Shigella dysenteriae and Shigella sonnei were identified using gas chromatography instead of the traditional techniques. Their acid methyl esters profiles were determined using a gas chromatograph Hewlett Packard 5890A and a RSL-150 heliflex capillary column. A total of 192 samples were analyzed both reference strains (ATCC 8700, INDRE B2188, B2194 and B2199) and environmental isolates. 12 fatty acids were included in the profiles from which 3-hydroxytetradecanoic acid (peak 12), trans 9-octadecanoic acid (peak 22), heptadecanoic acid (peak 18) and octadecanoic acid (peak 23), were the most important for the differentiation of the species analyzed.