PubMed Health⌕ Search

Biomedical subjects

J A Barreto

Publications and source records attributed to J A Barreto.

3 recordsLinked to original sources

A landscape parametric profile approach for rat brain image analysis.

This paper develops the use of the landscape parametric profile as a descriptive and interpretative method of analyzing metabolic activity data obtained by neuroimaging techniques such as 2-deoxyglucose autoradiography. The method is suggested as an initial survey-type approach that can be used to map regional activity throughout the coronal planes of a rat brain and to compare relative differences in the patterns of activity between different brains. Images are acquired using preexisting image analysis software and then transformed to landscape parametric profiles derived from each matrix array. The image profile analysis tasks are done using commercially available software for matrix computations such as MATLAB. An effective way of interpreting activity differences between brains is presented by plotting the results from a randomized blocks ANOVA significance test combined with the average profiles of different subjects within the same experimental group. The method greatly reduces the computational burden associated with image averaging and statistical comparison of brains from different subjects while preserving the richness in topographic metabolic information. One significant advantage of the method is that it results in figures that are readily depicted and interpretable in black and white.

Analysis of Variance↗

Isolation of Mycobacterium avium complex from bone marrow aspirates of AIDS patients in Brazil.

Mycobacterium avium complex (MAC) infection has not been reported as a major opportunistic infection among patients with AIDS in Latin America or Africa. In this study, 125 AIDS patients who had persistent fever, anemia, and leukopenia were examined among 2628 AIDS patients admitted to Instituto de Infectologia Emilio Ribas between May 1990 and April 1992. From the bone marrow aspirates of the 125 patients, MAC was isolated from 23 (18.4%) and Mycobacterium tuberculosis was isolated from 9 (7.2%). Between 1985 and 1990, only 11 MAC isolations among 60,000 cultures obtained from human immunodeficiency virus-seronegative patients were documented in São Paulo. Hence, the minimal estimated rate of MAC infection in AIDS patients in this city was 23/2628, or 0.88%. These findings suggest that MAC infection is an important opportunistic infection, especially among a subset of patients with AIDS in Brazil who have clinical characteristics and risk activities similar to those associated with MAC infections in North America and Europe.

AIDS-Related Opportunistic Infections↗

[Hemorrhagic angiodysplasia of the upper digestive tract: endoscopic diagnosis and treatment].

Angiodysplasia of the gastrointestinal (GI) tract is considered probably the most common cause of the occult bleeding. This paper analyses retrospectively 8 patients with angiodysplasia from upper GI tract. Two of them had Rendu-Osler-Weber syndrome. The main symptom was upper GI bleeding and 5 patients had acute melena and 3 chronic-intermittent bleeding. The diagnosis of angiodysplasia was confirmed by endoscopy. All patients but one underwent endoscopic treatment by injections of sclerosant and vasoconstrictor agents. One patient had hemigastrectomy and died in the post-operative. In the follow-up of 10 to 41 months, 2 patients died, one with bronchial carcinoma and the other due to cardiopulmonary failure. There was no bleeding recurrence in 5 patients. The endoscopic therapy should be the first choice if it is feasible, considering its efficacy as well as the low cost and safety.

Aged↗