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T de Brito

Publications and source records attributed to T de Brito.

At least 19 recordsLinked to original sources
PubMed1992

Treated-cured indeterminate leprosy: a search for predictive histopathological and immunohistochemical parameters in skin biopsies taken from patients at admission and at clinical discharge.

In a previous study an index (sigma 3) resulting from the summation of three parameters, i.e., presence of bacilli, even in small numbers, in various dermal structures, multiple positive antigen sites as detected by anti-BCG antiserum and dermal nerve involvement, identified 72.22% of cases of indeterminate leprosy which progressed to multibacillary leprosy. The present study was undertaken to investigate possible parameters which might be indicative of indeterminate leprosy which would persist unchanged or be cured (treated cured patients). Thirty treated cured indeterminate leprosy patients were selected from the files of the São Paulo Health Institute and studied by histopathological, immunohistochemical and statistical methods similar to those employed in the previous study. The sigma 3 index was 4.10 +/- 0.60, a finding that places this group of patients in a position close to that of patients changing to paucibacillary leprosy but statistically different from that of patients progressing to multibacillary leprosy. Moreover, it was found that patients belonging to this group have heterogeneous single parameters, some of them suggestive of multibacillary and others of paucibacillary leprosy. Immunologically based techniques mainly employing rabbit anti-BCG serum as the primary antibody have proved to be valuable to detect antigen sites in biopsies from indeterminate leprosy patients and should be used together with the bacillary index during the follow up and clinical discharge control of such patients. In the present study, we show that clinical discharge of these patients did not mean a complete clearance of bacillary antigens.

Academies and Institutes↗
PubMed1989

The prevalence of unsuspected thyroid pathology in 300 sequential autopsies, with special reference to the incidental carcinoma.

Three-hundred whole thyroid glands were collected at autopsy from patients who had no known clinical history of thyroid disease, and who varied from 13 to 82 years of age; 200 were male and 100 female. Thyroid glands were weighed, measured, and examined after previous formalin fixation. Histologic examination was done in 16 areas from both lobes and isthmus, and divided into three levels, anterior, medial, and posterior. All areas suspected of neoplasia macroscopically were identified and studied microscopically; other areas were collected randomly for microscopic examination in the proportion of one fragment per 5 grams of tissue. In all cases both benign and malignant neoplasias were an incidental finding, seen in 6.6% of the cases and with no relation to the patient's main disease. Overall, there were malignant neoplasias in 2.33% but occult carcinoma comprised 1% of the cases. The incidence of other thyroid pathologies, all of them unrelated to the main disease of the patient, are also reported.

Adolescent↗
PubMed1989

Cutaneous leishmaniasis of the New World: diagnostic immunopathology and antigen pathways in skin and mucosa.

Non-specific chronic inflammation and/or granulomatous reaction are the main histopathological manifestations of cutaneous and mucocutaneous leishmaniasis of the New World. Plasma cell infiltration associated with collagen and vascular changes are data suggestive but not diagnostic of the disease. Specific diagnosis is only possible through demonstration of the parasite in the tissue examined. It is noteworthy that the parasites are usually scanty and difficult to demonstrate in the lesions. Biopsies from 40 patients with cutaneous or mucocutaneous leishmaniasis were examined using the immunofluorescence and immunoperoxidase techniques in order to demonstrate the parasite and/or antigen in the tissues. Nineteen biopsies showed non-specific chronic inflammation and 21 a granulomatous reaction. Parasites were found in 20% of the routine biopsies. The positivity through indirect immunofluorescence was 88.46% in frozen sections of fresh material and 89.28% in paraffin embedded tissue. The antigen positivity with the immunoperoxidase technique was 64.51%. Antigen was detected as amastigotes and also as diffuse material in the macrophage cytoplasm and adsorbed in the epithelial basement membrane and vessel walls. There was no difference in the positivity of antigen according to the type of inflammatory reaction.

Animals↗
PubMed1989

Intrahepatic bile duct changes in human hepatosplenic schistosomiasis mansoni.

Wedge liver biopsies of 132 patients with hepatosplenic mansonian schistosomiasis were studied and divided in two groups according to the presence (Group I - 69 cases) or absence (Group II - 63 cases) of markers of the actual presence of the parasite in the liver tissue. Histological variables indicating bile duct injury were analysed in each case: periductal fibrosis, hyperplasia of the bile duct epithelium, bile duct degeneration, and marginal ductular proliferation. The presence of one or more of these variables defined two sub-groups: A - bile duct lesions present (73 cases), and B - bile duct lesions absent (59 cases). The variables "bile duct degeneration" and "ductular proliferation" were related to the actual presence of the parasite in the host. In 55.3% of all cases of human mansonian schistosomiasis a spectrum of injuries to the bile ducts was present. Epithelial hyperplasia alone or associated with patterns of mucopolysaccharide production was observed in 87.6% cases of the Sub-group A. The bile ducts changes in mansonian schistosomiasis are close to those described in liver fluke infestations such as clonorchiasis, fascioliasis and opistorchiasis. Statistical analysis revealed that high mucopolysaccharide production was associated with epithelial hyperplasia. The pathogenesis of the bile duct changes in human mansonian schistosomiasis and its relation to the parasitic infestations and their antigens is discussed.

Bile Ducts, Intrahepatic↗
PubMed1987

Cardiovascular involvement in human and experimental leptospirosis: pathologic findings and immunohistochemical detection of leptospiral antigen.

Twenty hearts from patients dying of leptospirosis were studied. Interstitial myocarditis was found in 50% of the cases, and a significant statistical correlation was observed between myocarditis and the inflammatory involvement of the conduction tissue. Acute coronary arteritis, affecting the main branches of the coronary arteries, was observed in 70% of the cases, and this finding also correlates significantly with interstitial myocarditis. Aortitis was found in 57.8% of the cases. When serum against L. interrogans serovar icterohaemorrhagiae was used, focal IP antigen deposits were observed in the coronary arteries and in the aorta. Experimental data from 12 guinea-pigs inoculated with L. interrogans serovar icterohaemorrhagiae showed a focal myocarditis involving mainly the subendocardial and pericoronary heart tissue, with IP antigen deposits in the same sites. Leptospirosis might be visualized as a generalized illness resembling other infectious vasculitides. The heart and main vessels are involved during the septicaemic phase of the disease, and bacterial migration, toxin(s), enzymes and/or antigenic products liberated by bacterial lysis might account for the increased endothelial permeability with antigen deposits and inflammation.

Adult↗
PubMed1983

Histopathology of the human liver in yellow fever with special emphasis on the diagnostic role of the Councilman body.

Liver specimens from 10 cases of yellow fever (YF) were studied by light and four by electron microscopy to review morphological aspects of the disease relevant to its diagnosis, with special emphasis on acidophilic bodies (AB) and on the possible presence of the virus within infected cells. The AB were compared with those found in 22 out of 69 liver specimens with other pathological processes. In YF the typical alteration was an acidophilic hepatocellular necrosis with a preferential midzonal distribution. Ceroid pigment was abundant, its amount was proportional to the degree of liver cell damage and it was found in altered hepatocytes and Kupffer cells in the most damaged areas. The inflammatory infiltrate was scanty, not only in portal tracts but also within the lobules. Electron microscopically, no viral particles were found in liver cells or AB. The latter appeared as round or elliptical cytoplasmic masses, surrounded by a conspicuous cellular membrane and densely packed with organelles, fat vacuoles and residual bodies. They differed from AB in other liver diseases by the presence of fat vacuoles and ceroid pigment. Some peculiarities of AB in other liver diseases such as presence of bile pigment and iron, would depend upon the presence of these pigments in the hepatocytes which originated them.

Humans↗
PubMed1978

Relationship between glomerular mesangial cell proliferation and amyloid deposition as seen by ultrastructural and morphometric analysis in experimental kala-azar of the hamster.

Light and electron microscopic studies combined with a morphometric analysis of the hamster glomerulus in experimental kala-azar showed progressive hyperplasia of mesangial cells beginning on the 10th day and reaching a peak on the 20th day after infection. Afterward, the number of mesangial cells declined and a progressive rise of amyloid deposits over the mesangial matrix was observed. This system for amyloid production is unique if we consider that probably one cell, the mesangial cell, is involved in glomerular amyloid deposition. Our data support a slight modification in the sequence of events of the biphasic theory of amyloid formation. We observed that the number of mesangial cells declines when amyloid deposition increases and that mesangial cell morphology in this stage is not that of an actively secreting cell. It is therefore hypothesized that amyloid precursor material is secreted into the matrix during the proliferative phase. In the second phase, amyloid deposits occur in the extracellular media close to functionally impaired mesangial cells.

Amyloid↗
PubMed1977

Jaundice in typhoid hepatitis: a light and electron microscopy study based on liver biopsies.

Light and electron microscopy study of fourteen liver biopsies in typhoid fever disclosed a mild hepatitis in which there is marked reticulo-endothelial hyperplasia, with many lymphoid cells in the hepatic sinusoids. The hepatic cell lesion was non specific, manifested by reticulum endoplasmic dilatation, mitochondrial alteration and biliary canaliculus injury. Such findings were particularly evident in the jaundiced patients. Jaundice was, in our series, a more frequent complication of acute typhoid fever than commonly reported. Usually it is of short duration and the serum bilirubin was not markedly elevated. However, there were instances when the jaundice was so accentuated as to lead the clinician to a first diagnosis of virus hepatitis or leptospirosis. The pathogenesis of the intrahepatic cholestasis in typhoid fever is still obscure, but apparently it is, as has been described in other infectious diseases, due to an injury of the bile secretory apparatus brought out by the bacillary endotoxin.

Adolescent↗
PubMed1976

Pathogenesis of cutaneous lesions in acute meningococcemia in humans: light, immunofluorescent, and electron microscopic studies of skin biopsy specimens.

Biopsy specimens of the skin were taken from 10 patients with acute meningococcemia who exhibited mainly maculopurpuric lesions. The specimens were studied by light, electron, and immunofluorescent microscopy in an attempt to obtain information on the pathogenesis of vascular injury. Light microscopy disclosed a large number of Neisseria meningitidis organisms, both in the endothelial cells and being phagocytized by neutrophils. Vascular injury was characterized (by means of both light and electron microscopy) by endothelial necrosis, thrombosis, and necrosis of other elements of the vascular wall, such as muscle cells and pericytes. Immunoglobulins and complement were also found in the vascular wall in most cases. Hypercoagulability was demonstrated in some patients. These findings suggest that the cutaneous lesions of meningococcemia fulfill most of the gross and histologic criteria of the local Shwartzman reaction, but that immunological factors probably contribute to pathogenesis.

Blood Coagulation Tests↗
PubMed1970

Kidney biopsy in the hepatosplenic form of infection with Schistosoma mansoni in man.

A study of early glomerular lesions was made in 8 patients infected with Schistosoma mansoni but having no clinical evidence of renal disease. Electron-microscopy of renal biopsies showed the presence of electron-dense deposits in basement membranes and of laminated bodies near the mesangial cells. Immunofluorescence showed that the deposits corresponded to IgG in 8 cases and to IgM in 2 cases. These lesions are comparable with those found in the kidneys of patients with cirrhosis of the liver.

Biopsy↗