Navegando por Palavras-chave "Ocular toxoplasmosis"
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- ItemSomente MetadadadosMorphometric changes in C57BL/6 mice retina infected by Toxoplasma gondii ME 49 strain(Elsevier B.V., 2014-01-01) Higino Rocha, Ana Cristina; Calabrese, Katia da Silva; Tedesco, Roberto Carlos [UNIFESP]; Campos, Wesley Ribeiro; Neto, Miguel Houri; Vasconcelos, Anilton Cezar; Orefice, Fernando; Universidade Federal de Minas Gerais (UFMG); Fundacao Oswaldo Cruz; Universidade Federal de São Paulo (UNIFESP)This study evaluated the morphometric implications in C57BL/6 mouse retina infected by Toxoplasma gondii, ME 49 strain. Twenty C57BL/6 female mice were divided into group 1 (n = 8, intraperitoneally infected with 30 cysts of T. gondii ME 49 strain) and group 2 (n = 12 non-infected controls). the eyes were enucleated on the 60th day after infection, fixed and processed for light microscopy. Changes in retinal thickness and in the perimeter/area ratio (P/A) of the retinal layers were analyzed by digital morphometry. We considered that P/A was the measurement of retinal architecture distortion induced by toxoplasmosis. This study considered the ganglion cells and nerve fiber layers as a monolayer, thus six layers of retina were evaluated: photoreceptors (PRL), outer nuclear (ONL), outer plexiform (OPL), inner nuclear (INL), inner plexiform (IPL) and ganglion cells/nerve fiber monolayer (GNL). Histological analysis of infected mouse retina showed inflammatory infiltrate, necrosis, glial reaction and distortion of the retina architecture. It also presented increased thickness (167.8 +/- 24.9 mu m versus 121.1 +/- 15.4 mu m, in controls) and increased retinal thickness within the retinitis foci (187.7 +/- 16.6 mu m versus 147.9 +/- 12.2 mu m out of the retinitis foci). A statistically significant difference in P/A was observed between infected and uninfected mouse retinas. the same was observed in PRL, ON, INL and GNL. Retinal morphometry may be used to demonstrate differences between infected and uninfected mouse retinas. Published by Elsevier Inc.
- ItemAcesso aberto (Open Access)Neovascularização retiniana secundária a obstrução vascular em retinocoroidite por toxoplasmose em paciente HIV positivo: relato de caso(Conselho Brasileiro de Oftalmologia, 2004-08-01) Ewert, Vânia [UNIFESP]; Finamor, Luciana Peixoto [UNIFESP]; Dimantas, Maria Angélica [UNIFESP]; Muccioli, Cristina [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)To present a case of an HIV-infected patient, who presented with active chorioretinal inflammatory lesion suggestive of toxoplasmosis, that during the specific treatment developed a retinal vascular occlusion, and adjacent neovascularization. 35-year-old AIDS patient that, presented with toxoplasmic retinochoroiditis and after 4 weeks of the specific therapy (pyrimethamine and sulfadiazine) developed a vascular occlusion and retinal neovascularization that healed without the need for phototocoagulation or other adjunctive therapy. This case demonstrates that acute toxoplasmic retinochoroiditis that develops vascular complications may present a good result with the specific treatment without the need for adjunctive therapy.
- ItemSomente MetadadadosSerum and aqueous humour cytokine response and histopathological alterations during ocular Toxoplasma gondii infection in C57BL/6 mice(Elsevier B.V., 2008-12-01) Calabrese, K. S.; Tedesco, R. C. [UNIFESP]; Valle, T. Zaverucha do; Barbosa, H. S.; Fundacao Oswaldo Cruz; Universidade Federal de São Paulo (UNIFESP)Toxoplasma gondii, an obligate intracellular protozoan parasite, infects most species of warm-blooded animals, and in humans it causes toxoplasmosis. Healthy people that become infected rarely present clinical symptoms because the immune system prevents the parasite from causing illness. Congenital toxoplasmosis may result in abortion, hydrocephalus, as well as neurological and ocular disease (most frequently retinochoroiditis) of the newborn. in immunocompromised patients, reactivation of latent disease can cause encephalitis. Cell-mediated immunity to T gondii antigens involves innate acute inflammatory responses and antigen-specific adaptive immunity. Considering the complexity of the immunological events triggered during toxoplasmosis, systemic and local responses were evaluated by cytokine measurements. Aqueous humour and serum were obtained from non-infected and T gondii Me-49 strain infected C57BL/6 mice for cytokine quantification. Histopathological analyses were made with eyes enucleated from mice after 30 days of infection. ELISA assays showed an increase of IFN-gamma levels both in serum and aqueous humour of infected mice in opposition to a decrease in IL-10 levels. On the other hand, TGF-beta was high, whereas IL-12 and TNF-alpha were present in small levels in both groups. We also detected higher levels of IL-4 and IL-6 in aqueous humour than in serum of infected mice when compared to the control group. MIP-2 presented no significant differences between the two groups. Fas and Fas-L were also present in similar levels in serum of non-infected and infected mice, but both chemokines were increased in the aqueous humour of infected mice. Histopathological analysis of infected mice showed inflammatory infiltrates around blood vessels and alteration of the outer photoreceptor segments, on the external and inner nuclear layer. Parasites were observed in 82% of eyes, inside the blood vessels associated with inflammatory infiltrate. Edema, characterized by the increase of interstitial spaces between the FTR, forming lacunae was also noted. These alterations take the form of projections (retino-vitreal), characteristic of retinochoroiditis. in conclusion, T gondii infection of C57BL/6 mice revealed that cytokine patterns alone do not assure susceptibility or resistance against infection, thus reinforcing the notion that it is necessary more than cytokine dosage to determine Th1 or Th2 profile in this model. (C) 2008 Published by Elsevier B.V.
- ItemAcesso aberto (Open Access)Uveítes anteriores associadas a doenças sistêmicas(Conselho Brasileiro de Oftalmologia, 2003-01-01) Dimantas, Maria Angélica Pavão; Lowder, Careen; Muccioli, Cristina [UNIFESP]; Cleveland Clinic Foundation Setor de Uveítes; Universidade Federal de São Paulo (UNIFESP)Anterior uveitis describes a disease predominantly limited to the anterior segment of the eye. Conjunctival hyperemia, anterior chamber cell and flare, keratic precipitates, and iris abnormalities including posterior synechiae characterize the inflammation. This article discusses clinical aspects of the systemic diseases that cause anterior uveitis with review of the literature.