Xanthomonas (formerly Pseudomonas) maltophilia--induced cellulitis in a neutropenic patient.
Explore the source record for details and available documents.
Adult↗
Biomedical subjects
B N Pham
Publications and source records attributed to B N Pham.
Trypanosoma cruzi: infection of T lymphocytes and their destruction by antibody-dependent cell-mediated cytotoxicity.
We have demonstrated, with optical and transmission electron microscopy, that Trypanosoma cruzi trypomastigotes infect and multiply inside T lymphocytes. The infection rate we have observed in T cells was similar to that seen in the case of macrophage or polymorphonuclear cell infection. Flow cytofluorometric analysis of T lymphocytes purified from mice in the acute phase of the disease, revealed the presence of parasite-derived antigens on their surface. These antigens appear to be specific to T. cruzi and they could be the result of intracellular parasite antigens as well as adsorption of T. cruzi antigens on the surface of noninfected T cells. Antibodies recognizing these surface antigens were present in both T. cruzi-infected mouse and human sera. They were able to induce antibody-dependent cell-mediated cytotoxicity (ADCC) in the presence of nonimmune mononuclear cells both in autologous and in heterologous combinations. Consequently, we provided evidence suggesting that T lymphocytes could be destroyed during the acute phase of Chagas' disease either by cell infection or by an ADCC mechanism against cells bearing parasite antigens on their surface. Thus, the ability of trypomastigotes to invade T cells may play a crucial role in the immunopathogenesis characteristic of Chagas' disease.
Animals↗
T lymphocyte activation in systemic lupus erythematosus analysed by proliferative response to nucleoplasmic proteins on nitrocellulose immunoblots.
Polyclonal B cell activity in systemic lupus erythematosus (SLE) may be under T cell control. The use of nitrocellulose immunoblots for the analysis of recognition by peripheral blood lymphocytes of nucleoplasmic proteins in SLE patients led to the characterization of significant proliferative responses to 68K (U1 RNP); SS-B; B-B' and D (Sm) antigen in 15 of 20 patients. Variations of proliferative response were parallel to disease activity over a follow-up period of greater than or equal to 6 months, conferring some prognostic value to the assay of lymphocyte response to nucleoplasmic antigens. The pattern of reactivity differs from the corresponding serum antibody profile, and purified T cell suspensions (greater than 95% pure) were shown to proliferate in response to soluble nucleoplasmic antigens, indicating that T and B cell repertoires against nucleoplasmic proteins may differ. This suggests that activated helper T cells contribute to the fine modulation of B cell reactivity to subcellular particles to determine the particular antibody profile of the patients.
Adolescent↗
Ganglioneuromatous proliferation associated with juvenile polyposis coli.
A case of nonfamilial juvenile polyposis coli was associated ganglioneuromatous proliferation in the polyps is described. The ganglioneuromatous proliferation was characterized by clusters of mature ganglion cells and nerve fiber bundles in the lamina propria and submucosa of the juvenile polyps. The patient had no history of von Recklinghausen's disease or multiple endocrine neoplasia syndrome, type 2b. The implications of this peculiar finding are discussed and the literature is reviewed.
Adult↗
New brain-cutting box: its use in computerized axial tomographic scan and autopsy brain section correlation.
A new brain-cutting box aids in the sectioning of autopsied brains along planes that correspond to computerized axial tomographic (CT) scans levels. There are two plastic boxes, one inside the other. The inner one has a platform slanted at a 15 degree angle from the horizontal plane. The brain, resting on this platform, can be raised by elevating the inner box and can be sectioned along the horizontal upper free edges of the outer box. The resulting sections, cut at appropriate intervals, correspond to CT scans. This box has numerous advantages over existing brain-cutting devices.
Autopsy↗
[Monoclonal immunoglobulin: national external quality assessment and diagnostic reasoning].
In 2003, for the scheme of the French national external quality assessment, Afssaps sent to medical laboratories a sample for which two analyses could be carried out: the electrophoresis of proteins and the characterization for monoclonal immunoglobulin. The purpose of this new approach was to make it possible to the laboratories to transpose their usual diagnostic reasoning. This survey recalled to the biologists that it is necessary to check the sensitivity of the test of electrophoresis of proteins used in first intention and to use advisedly the anti-serums anti-free chains. Moreover this operation reinforced the educational aspect of the external quality assessment, pointing out the importance to ensure the coherence of the results of these two analyses carried out with a same diagnostic aim.
Antibodies, Monoclonal↗
[National external quality assessment in auto-immunity: autoantibodies detected on liver, kidney and stomach tissues].
In 2003, for the scheme of the French national external quality assessment, Afssaps organized for the first time a survey on auto-antibodies detected on liver, kidney and stomach tissues. This survey had two purposes: first to make an inventory of the methodology applied by the medical laboratories and secondly to assess the quality of the results. The survey sample contained M2 anti-mitochondrial antibodies. Overall results are satisfactory. Concerning the titer of antibodies, a broad dispersion of results was observed (12% of titers were upper than the expected titer). Delivered information to the participants, at the end of the survey, should improve analytical procedures applied by the biologists. An effort of standardization by using titrated internal controls would be suitable.
Autoantibodies↗
[National external quality assessment in auto-immunity: auto-antibodies against thyroid constituents].
The French Health Products Safety Agency organized in 2005, for the scheme of the national external quality assessment, a survey on antibodies against thyroid constituents which included for the first time the quantitative assay. The purpose of this survey was to assess the quality of the different methods of these assays. The overall qualitative results are satisfactory. However, this survey pointed out a lower performance for immunodot which appeared to have been misused. Concerning the titer of antibodies, results show a broad dispersion between reagents. This confirms the lack of a real standardisation despite of the existence of the international MRC standards.
Agglutination Tests↗