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Biomedical subjects

D Aguilar

Publications and source records attributed to D Aguilar.

At least 37 records · Page 2Linked to original sources
PubMed1993

Mononuclear cell subsets in IgM mesangial proliferative glomerulonephritis. A comparative study with minimal change nephrotic syndrome and immunonegative mesangial proliferative glomerulonephritis.

Glomerular and interstitial leukocyte subpopulations were analyzed in renal biopsies from 18 patients with IgM mesangial proliferative glomerulonephritis (IgM MPGN), 19 patients with minimal change nephrotic syndrome (MC) and 10 patients with immune-negative mesangial proliferative glomerulonephritis (IN MPGN), by immunoperoxidase techniques with monoclonal antibodies. Mesangial cell proliferation was strongly correlated with absolute numbers of intraglomerular T lymphocytes (r = 0.71; p < 0.01) in IgM MPGN, but not in MC or IN MPGN. Significant differences were found in the numbers of macrophages, CD4- and CD8-positive glomerular cells (Student's t test p < 0.01, 0.05 and 0.01, respectively) in IgM MPGN, but not in MC or IN MPGN. The numbers of CD45-, CD3- and CD8-positive cells also differed in each patient group (ANOVA p < 0.01, 0.05 and 0.05, respectively), the greatest and smallest values appearing in IgM MPGN and MC, respectively. Multiple regression test showed initial proteinuria values in IgM MPGN to be closely dependent on the density of neutrophils, macrophages, T and B lymphocytes and CD4 cell inflammatory infiltrates (r2 = 0.92; p < 0.01). At the end of the follow-up, proteinuria in IgM MPGN, but not in MC or IN MPGN, was dependent on T cell infiltrate (r2 = 0.97; p < 0.01). Our findings suggest that proteinuria in IgM MPGN results from local mesangial damage rather than from the effects of a soluble circulating factor, as has been proposed for MC. The clinical and immunohistochemical differences observed between these two processes support the notion that they should be considered as separate entities.

Adult↗
PubMed1992

Detection of lipoarabinomannan as a diagnostic test for tuberculosis.

A coagglutination technique was established for the detection of lipoarabinomannan of Mycobacterium tuberculosis in human serum samples and evaluated for its utility in the diagnosis of tuberculosis at the Instituto Nacional de Enfermedades Respiratorias in Mexico City. The test had a sensitivity of 88% in patients with sputum-smear-positive active pulmonary tuberculosis. The sensitivity in patients with active pulmonary tuberculosis negative for acid-fast bacilli in sputum was 67%. Less favorable results were obtained for patients with AIDS and tuberculosis, with a sensitivity of 57%. The specificity in control patients with lung diseases different from tuberculosis and in healthy subjects was 100%. The positive predictive value was 100%, and the negative predictive value for patients with sputum-positive active pulmonary tuberculosis was 97%. The results of this study suggest that the detection of lipoarabinomannan is an accurate test for the diagnosis of pulmonary tuberculosis.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Diffuse sclerosing papillary carcinoma of the thyroid gland: immunohistochemical analysis of the local host immune response.

Surgical specimens from four patients with diffuse sclerosing papillary carcinoma of thyroid were examined by electronmicroscopy. In addition, immunohistochemical examination using a panel of monoclonal and polyclonal antibodies was carried out in order to investigate the expression of HLA-DR antigen, the presence of Langerhans' cells and the phenotypic characteristics of the inflammatory infiltrate. The ultrastructural study showed that the intraglandular dissemination, typical of this tumour, was due to massive lymphatic invasion. Many Langerhans' cells were observed among tumour cells and in the lymphoid infiltrates in proximity to tumour foci. HLA-DR expression was seen on macrophages, Langerhans' cells, endothelial cells, lymphoid cells, many tumour cells and in some non-neoplastic follicles close to tumour clusters and lymphoid infiltrates. The immunohistochemical analysis of the inflammatory infiltrates showed a high proportion of B- and T-cells, and moderate numbers of plasma cells. Our results suggest that the tumour-specific immune response can give rise to an autoimmune reaction involving non-neoplastic follicles. It is suggested that this could be one of the mechanisms responsible for immunofacilitation of tumour growth.

Adolescent↗
PubMed1989

Differentiation in medulloblastomas: immunohistochemical study of twenty-one cases.

Twenty-one cases of medulloblastoma (MB), 20 corresponding to the classical type and 1 to the desmoplastic variant (DPM), were studied immunohistochemically with glial fibrillary acidic protein (GFAP), S-100 protein (S-100P), neuron-specific enolase (NSE) and 200-kd neurofilaments (NF) in order to assess their differentiation potential. Their respective positivities in neoplastic cells were: 42% for GFAP, 47% for S-100P, 61% for NSE and absence of NF. Isolated neoplastic cells (e.g., cells lacking processes and with scanty cytoplasm), appeared positive for neuroglial markers (GFAP and S-100P). Most cases, however, showed positive reactive neuroglial cells. NF were never found in neoplastic cells, but in trapped neuronal processes. In most cases, large numbers of cells had high positivity to NSE. Cells of lucent islands of DPM were positive for GFAP and S-100P, while Homer-Wright type rosettes showed positive only for NSE. The above results support a neuroglial differentiation in MB. NSE was considered a nonspecific marker for neuroblastic cells.

Adolescent↗
PubMed1989

[Malignant astrocytic glioma of the brain in adults: histologic criteria determining its classification, diagnosis and prognosis].

Eighty-three malignant supratenorial astrocytic gliomas in adult patients were evaluated. The patients underwent surgery and radiotherapy. To establish their influence on survival, 10 histological variables were evaluated (degree of cellularity, polymorphism, predominant cell type, nuclear atypia, mitotic index, vascular proliferation, endothelial hyperplasia, glomeruloid formations, lymphocytic infiltration, necrosis and pseudofences). Two definite levels of aggressivity were found (anaplastic astrocytoma and multiform glioblastoma) with statistically significant differences in survival (p less than 0.025). They were diagnosed on the basis of the presence or absence of necrosis. In the absence of this parameter, vascular phenomena, cellularity and nuclear atypia were found to be valid for the differentiation of the two mentioned groups.

Adolescent↗
PubMed1988

Hamartomatous solitary polyp with malignant progression in the jejunum. A histochemical and immunohistochemical study by light and electron microscopy.

A case of solitary hamartomatous jejunal polyp with adenomatous and carcinomatous changes in a 16-year-old girl is reported. In the hamartomatous polyp, neutral and acid non-sulfate mucosubstance was detected, principally in goblet cells; carcinoembryonic antigen was demonstrated on the surfaces of the microvilli and luminal border of the crypts and glands; absorptive columnar, goblet, argentaffin, argyrophil and Paneth cells were evident. The adenomatous and, mainly, the carcinomatous areas revealed a decreased amount of mucosubstance and a variable degree of positive intracytoplasmic staining for carcinoembryonic antigen. With electron microscopy, the adenomatous areas showed columnar absorptive cells and mucus-secreting goblet cells; also immature columnar cells were observed in the dysplastic zones. To our knowledge, this is the first study to document the histochemical, immunohistochemical and ultrastructural features of a hamartomatous polyp with neoplastic transformation.

Adolescent↗
PubMed1988

Human melanoma cell lines: an immunofluorescence and ultrastructural study.

Two human melanoma cell lines (OAL-1 and OAL-2) were obtained from primary tumors. Electron microscopy and indirect immunofluorescence for S-100 protein and human melanoma associated antigen p97a were used to characterize the cell lines. Ultrastructural correlation between primary tumor cells and cultured cells was investigated. The ultrastructural features of OAL-2 cells were similar to those of primary tumor cells. However, OAL-1 cells showed a fibroblast-like appearance, quite different from that of the primary tumor cells. This fibroblast-like appearance persisted after 50 subcultures of the OAL-2 cell line and suggests cellular dedifferentiation. No spontaneous redifferentiation of the cells to the original phenotype of the primary tumor cells was observed even after 50 subcultures.

Aged↗
PubMed1984

Trophectoderm in control of murine embryonal carcinoma.

It has been shown previously that the intact blastocyst of the mouse can regulate tumor formation and colony formation of murine embryonal carcinoma. This effect is consistent with the close histogenetic correspondence between embryonal carcinoma and the inner cell mass of the blastocyst. The ability of inner cell mass, blastocele fluid, and inner and outer surfaces of trophectoderm to abrogate colony formation of a variety of malignant tumors has now been tested. Direct contact of the embryonal carcinoma cells with the blastocele surface of trophectoderm proved to be necessary for abrogation of colony formation of embryonal carcinoma. This effect was not seen with any of the other tumors tested. Some tumors, which lack a normal cellular counterpart in the blastocyst, grew poorly in the blastocele unless a fistula was made in the wall of the blastocyst. Colony formation of the embryonal carcinoma was regulated in blastocysts with fistulas, but the other tumors were not regulated under these conditions. It is concluded that colony formation of embryonal carcinoma cells is regulated by direct contact with the trophectoderm of its corresponding embryonic field in an unknown but specific manner.

Animals↗
PubMed1982

Benign heterologous tissue components associated with endometrial carcinoma.

Two cases of adenocarcinoma of the endometrium associated with benign mesenchymal tissues of adipose and osteoid type are presented. These components have a metaplastic or metamorphic, rather than neoplastic, origin. Heterologous elements associated with adenocarcinoma should not be mistaken for the more common mixed mesodermal müllerian tumors which have a different clinicopathologic behavior.

Adenocarcinoma↗