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Biomedical subjects

L M Olivares

Publications and source records attributed to L M Olivares.

4 recordsLinked to original sources
PubMed2001

Signaling lymphocytic activation molecule expression and regulation in human intracellular infection correlate with Th1 cytokine patterns.

Induction of Th1 cytokines, those associated with cell-mediated immunity, is critical for host defense against infection by intracellular pathogens, including mycobacteria. Signaling lymphocytic activation molecule (SLAM, CD150) is a transmembrane protein expressed on lymphocytes that promotes T cell proliferation and IFN-gamma production. The expression and role of SLAM in human infectious disease were investigated using leprosy as a model. We found that SLAM mRNA and protein were more strongly expressed in skin lesions of tuberculoid patients, those with measurable CMI to the pathogen, Mycobacterium leprae, compared with lepromatous patients, who have weak CMI against M. leprae. Peripheral blood T cells from tuberculoid patients showed a striking increase in the level of SLAM expression after stimulation with M. leprae, whereas the expression of SLAM on T cells from lepromatous patients show little change by M. leprae stimulation. Engagement of SLAM by an agonistic mAb up-regulated IFN-gamma production from tuberculoid patients and slightly increased the levels of IFN-gamma in lepromatous patients. In addition, IFN-gamma augmented SLAM expression on M. leprae-stimulated peripheral blood T cells from leprosy patients. Signaling through SLAM after IFN-gamma treatment of Ag-stimulated cells enhanced IFN-gamma production in lepromatous patients to the levels of tuberculoid patients. Our data suggest that the local release of IFN-gamma by M. leprae-activated T cells in tuberculoid leprosy lesions leads to up-regulation of SLAM expression. Ligation of SLAM augments IFN-gamma production in the local microenvironment, creating a positive feedback loop. Failure of T cells from lepromatous leprosy patients to produce IFN-gamma in response to M. leprae contributes to reduced expression of SLAM. Therefore, the activation of SLAM may promote the cell-mediated immune response to intracellular bacterial pathogens.

Antibodies↗
PubMed1988

[Cardiac involvement in scleroderma].

It has been analyzed seven patients, five females and two males, affected by progressive systemic sclerosis. Their ages range from 35 to 60 years. Three of them correspond to the CREST syndrome named variant. There were made: physical examination, electrocardiogram, echocardiogram and radionuclide techniques such as: Thallium perfusion (T201) and ventriculography (Tc99). The cardiac examination of all the patients showed: Left myocardiopathy in six patients, as well right myocardiopathy in two of them. Four patients were affected by chronic cor pulmonale, due to pulmonary hypertension. All the patients had developed diffuse thallium perfusion defects as well, having abnormal resting left ventricular function in three patients and function abnormality from right ventricle in two patients. It is necessary to point out the importance of making such study systematically, even in the case cardiac symptoms absence.

Adult↗
PubMed1987

[Cardiac repercussions in the CREST syndrome].

Two females patients with CREST syndrome associated with cardiac involvement are reported. One of them has pericardial effusion just shown by echocardiography with patterns of cardiomyopathy of ventricular cavities, the latter as primary myocardial involvement, in the absence of pulmonary or systemic hypertension. The second patient has chronic cor pulmonale secondary to pulmonary hypertension verified by electrocardiography and echocardiography. It is emphasized the utility of the echocardiography and the importance of those anomalies that can lead to the patient's death, transforming the CREST towards a syndrome with potentially but late, severe systemic involvement.

Adult↗