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Biomedical subjects

M Pastor

Publications and source records attributed to M Pastor.

53 records · Page 3Linked to original sources
PubMed1994

Cholinergic modulation of immunoglobulin secretion from avian plasma cells: the role of calcium.

The existence of a functional connection between the nervous and immune systems has long been argued. To determine if such a link exists in the secretory immune system, we have examined the avian lacrimal gland (Harderian gland) which contains large numbers of plasma cells. We have shown that these plasma cells bind an antibody to muscarinic acetylcholine receptor and that carbachol, an acetylcholine agonist, increases the secretion rate of IgG by these cells above a constitutive baseline level. This neurotransmitter-dependent increase of immunoglobulin secretion requires an influx of Ca2+, whereas the constitutive baseline secretion is apparently less dependent on such a flux. Furthermore, the Ca2+ flux appears to be mediated by voltage-dependent calcium channels. These data support the hypothesis that plasma cells can respond to neurotransmitters and, in the case of acetylcholine, increase immunoglobulin secretion.

Animals↗
PubMed1990

The deoxyuridine suppression test in peripheral lymphocytes.

The effects of different deoxyuridine (dU) concentrations on lymphocytes stimulated with phytohemagglutinin (PHA) were studied for use in a lymphocyte dU suppression test (L-dUST). High concentrations of dU were necessary to overcome the unspecific spontaneous pattern of folate deficiency, dU suppression tests with cells of bone marrow (BM-dUST) and with lymphocytes were carried out in 15 patients with vitamin B-12 deficiency, in 12 with folate deficiency, and in 10 with other pathological conditions. L-dUST was also carried out in 15 healthy reference controls. The BM-dUST was able to distinguish patients with vitamin B-12 or folate acid deficiencies from those without, while the L-dUST was unable to do so in most cases. L-dUST does not, therefore, appear to be a reliable method for the diagnosis of megaloblastic changes.

Bone Marrow↗
PubMed1990

[Evaluation of methods for the detection of syncytial respiratory virus in nasopharyngeal secretions].

The screening for respiratory syncytial virus (RSV) in nasopharyngeal secretions with enzyme immunoassay (ELISA) and indirect immunofluorescence (IIF) has been evaluated in infants and young children with acute respiratory infection. Both methods were compared with viral isolation in HEp-2 cells and the investigation of fluorescent foci in cell cultures inoculated by centrifugation. 226 samples were evaluated by IFF, 182 of which were also evaluated by ELISA while 158 were inoculated into cell cultures. 20.35% of samples were positive with IFF and 19.23% with ELISA. Isolation of RSV was obtained in 25 of the samples inoculated into HEp-2 cells (15.8%). The cytopathic effect took a mean of 5.4 days to develop. The investigation of fluorescent foci in centrifugated cultures allowed to detect 76% of positive samples 24 hours after centrifugation and 84% of positive samples 48 hours after it. Considering the viral isolation as the reference method, IIF and ELISA had a 88% and 76% sensitivity, respectively, with very similar specifities (90.2% and 91.7%).

Enzyme-Linked Immunosorbent Assay↗
PubMed1984

Generalized Castleman's disease with urinary elimination of heavy chain fragments.

A generalized form of Castleman's disease of transitional type is reported in a 66-year-old male who was found in addition to have gamma heavy chain fragments in his urine. One portion of them was constituted by Fc fragments and the other ones by fragments which reacted with anti-Fab/IgG and anti-Fc/IgG antisera but not with anti-kappa and anti-lambda antisera. The findings of the present case support an immunological basis for Castleman's disease.

Aged↗
PubMedDate not supplied

Long-term follow-up and prognostic factors in Ewing's sarcoma. A multivariate analysis of 116 patients from a single institution.

The records of 116 patients from a single center (1970-1993) with newly diagnosed Ewing's sarcoma or primitive neuroectodermal tumor were reviewed retrospectively. The aim of this study was to ascertain the impact of pretreatment variables on disease-free survival. Median age was 14 years (range 1-34). Twenty patients presented with metastatic disease. Treatment consisted of systemic multiagent chemotherapy plus local irradiation (39%), wide resection (22%), or both (35%). Median potential follow-up was 10.7 years (range 2-26). Three patients developed second malignancies (1 breast carcinoma, 2 acute myeloid leukemias). Median time to relapse was 24 months (range 3-143). The actuarial disease-free survival was 37.4% at 5 years, 33.3% at 10 years and 27.8% at 15 years. Neoadjuvant chemotherapy and a therapy-induced tumor necrosis > or = 90% were associated with a better outcome. Patients undergoing surgical resection had a superior disease-free survival than those treated without surgery (45 vs. 18% at 10 years, p = 0.0009). Multiple regression analysis showed that raised serum lactate dehydrogenase levels (p < 0.001), hypoalbuminemia (p = 0.001) and distant metastases at diagnosis (p = 0.03) were independent adverse prognostic factors. In conclusion, one third of patients with Ewing's sarcoma become long-term survivors with combined modality treatment. Late relapses and second neoplasms are of concern. Prognostic factors should be considered in the selection of therapy, and the value of serum albumin warrants confirmatory studies.

Actuarial Analysis↗
PubMedDate not supplied

Intravitreal ganciclovir for cytomegalovirus retinitis in patients with AIDS.

OBJECTIVE: To assess the evolution of cytomegalovirus (CMV) retinitis and evaluate the possible complications associated with the use of intravitreal injections to treat this disease. DESIGN: A nonrandomized, retrospective study with case series was performed. The study took place over 34 months. SETTING: The study included patients with AIDS who developed CMV retinitis, and who were treated in the hospital, as outpatients, or both. PATIENTS: Twelve patients with AIDS and CMV retinitis diagnosed between June 1990 through April 1993 were included in the study. MAIN PATIENT PARAMETERS AND OUTCOME MEASURES: For each patient, the following data were recorded: age, risk factors, other systemic findings, dates of AIDS and CMV retinitis diagnoses, stage of AIDS, extent of the retinitis, CD4 lymphocyte count at the time of diagnosis of retinitis, visual acuity, clinical evolution of the ocular infection, therapy, complications caused by the treatment, development on nonocular CMV, and the use of zidovudine or didanosine during the study period. RESULTS: Vision improved or remained stable in nine patients and worsened in three. Two patients developed optic neuritis. The retinitis progressed to the other eye in only one of the eight patients who had unilateral involvement. The rate of relapse with maintenance therapy was 8.3% (n = 1) within the first 8 weeks. Treatment was well tolerated. There was no evidence of toxicity after a total of 226 intravitreal ganciclovir injections. All patients were able to tolerate zidovudine or didanosine concomitantly with intravitreal ganciclovir. CONCLUSIONS: Intravitreal ganciclovir appears to be an effective alternate to systemic ganciclovir in patients with severe neutropenia and in patients who choose to continue receiving systemic zidovudine or didanosine. Early treatment and long-term maintenance therapy is essential for preserving sight.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

Shared HLA antigens between parents and recurrent spontaneous abortion.

Ten couples with a history of at least three (mean 3.8) consecutive spontaneous abortions of unknown etiology and 57 normal fertile couples (means 2.6 children) were tested for HLA antigens. The frequencies of shared HLA-A, -B and -DR antigens among members of the couples were similar in both groups. Our results, as well as analysis of the data in the literature, contradict HLA antigens sharing between parents as a determinant of recurrent spontaneous abortion.

Abortion, Habitual↗