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I Candelori

Publications and source records attributed to I Candelori.

3 recordsLinked to original sources

[High resolution light microscopy: adaptation of the method and its use in the study of experimental leptospirosis in guinea pigs].

Morphological lesions in parenchimal and mesenchimal structures of liver and kidney were studied in guinea-pigs experimentally infected with Leptospira interrogans serogroup icterohaemorrhagiae in comparison with a group of non-infected guinea-pigs. All specimens were submitted to conventional light microscopy as well as to high resolution light microscopy, in one micrometer sections of tissue embedded in glycolmethacrylate. High resolution light microscopy, applied for the first time in leptospirosis, was proved very useful, since it enabled us to visualize cellular structures in the same slide used for panoramic view. Cell cohesion, brush borders, pynocytotic vesicles and organellae distributions were parameters especially suitable for analysis at this low-cost, highly precise procedure in microscopy.

Animals

Urticarial vasculitis.

Thirty seven patients with chronic urticaria were prospectively studied from August 1984 to July 1986. These patients were submitted to regular and immunological laboratory tests. Biopsies were taken from recent urticarial lesions for histologic analysis and also to direct immunofluorescence and immunohistochemistry studies. Vasculitis was found in 27% of the patients. Most of them showed only urticarial lesions except two (20%), that presented residual macula; angioedema occurred in 20% of the urticarial vasculitis (UV) patients; most cases had no systemic manifestations. Serum immunoglobulins and circulant immunocomplexes were increased in both groups. Complement reduction was considered an evidence of vascular aggression, being found in 55% of the UV patients. Direct immunofluorescence studies showed only 10% of positive IgM fluorescence in the vessel walls in the UV group. Immunohistochemical evaluation in the same group revealed mainly slight deposition of immunoglobulins IgG, IgM and IgA in the plasma cells of 80% of the samples and in only 10% there was immunoglobulin deposition in the vessel walls. The authors concluded that conventional histopathology is the best diagnosis method for urticarial vasculitis, direct immunofluorescence and immunoperoxidase being ancillary tools. Therefore, a special group of patients was detected, clinically and therapeutically resembling common urticaria patients, but presenting vasculitis in the histologic exam. This fact leads to the hypothesis that there is a range between common urticaria and urticarial vasculitis with systemic involvement.

Adult

[Glycoproteins from Leptospira interrogans serogroup icterohaemorrhagiae: distribution in the liver and kidney of experimentally infected guinea pigs].

Tissue damage in leptospirosis has been ascribed to direct effect of the microorganisms and/or their virulence, including products synthetized by leptospires or released during their lysis. This study aimed at chemical extraction of the glycolipoprotein (GLP) from virulent leptospires, production of a rabbit anti-GLP and analysis of its distribution in liver and kidney of inoculated guinea-pigs, sacrificed sequentially from the 1st to 6th day of infection, covering the whole, spectrum of acute leptospirosis. The comparison of GLP expression to local injuries aimed at new pathogenetic data. GLP was detected in liver and kidney in 2 out of 6 guinea-pigs on the 5th day and in all 6 animals on the 6th day of infection. Granular forms were seen in the cytoplasm of macrophages, free in interstitium or adhered to endothelial and parenchymal cell membranes, especially in the most damaged sites. These findings lead us to the hypothesis of GLP as a toxic factor resulting from leptospiral lysis by macrophages. Although it was not proved as a promoter of initial lesions, it seems to be related to the enhancement of tissue damage late in the course of the disease.

Animals