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Biomedical subjects

A Fischer

Publications and source records attributed to A Fischer.

At least 739 records · Page 41Linked to original sources
PubMed1985

Genotyping with DNA probes in combined immunodeficiency syndrome with defective expression of HLA.

We performed HLA genotyping by using restriction-enzyme fragments hybridized with specific HLA probes instead of traditional immunologic methods in two patients whose lymphocytes expressed so few HLA antigens on the cell surface that serologic methods failed. Segregation of restriction-fragment-length polymorphism permitted identification of the genotypes. In addition, known correlations between serologically determined antigens and restriction-fragment-length polymorphism were confirmed. We applied this approach in making therapeutic decisions regarding bone marrow transplantation.

Bone Marrow Transplantation↗
PubMed1985

Heparin with and without graded compression stockings in the prevention of thromboembolic complications of major abdominal surgery: a randomized trial.

One hundred and seventy-six patients scheduled for elective major abdominal surgery were randomized to two prophylactic regimens to prevent postoperative thromboembolism. All patients were screened with the 125I-labelled fibrinogen uptake test, and thromboembolism was verified by ascending phlebography and/or perfusion/ventilation lung scintigraphy. In the group of patients receiving low-dose heparin treatment (5000 units twice daily subcutaneously) 12 per cent developed thromboembolic complications. In the other group, where low-dose heparin treatment was supplemented with graded compression stockings only 2 per cent developed thromboembolism. It is concluded that the combination of low-dose heparin and the use of graded compression stockings is superior to heparin alone in preventing thromboembolism following major abdominal surgery.

Abdomen↗
PubMed1985

Determination of chlorpromazine and its major metabolites by gas chromatography/mass spectrometry: application to biological fluids.

A method for the quantitative determination of chlorpromazine and five of its major metabolites in a single sample of biological fluid in the ng/ml range has been developed utilizing gas chromatography/mass spectrometry with selected ion recording. The assay is highly specific and quantification is accomplished by an inverse stable isotope dilution technique, using deuterium-labeled variants of the compounds as internal standards. In this way the concentrations of chlorpromazine and five of its major metabolites (the sulfoxide, the N-oxide, the monodemethylated, the didemethylated, and the 7-hydroxylated compounds) can be determined in biological fluids. Levels in humans have been measured both in plasma and in red blood cells and are compared to those found in related in vitro studies.

Biotransformation↗
PubMed1985

HLA class II restriction governing cell cooperation between antigen-specific helper T lymphocytes, B lymphocytes and monocytes for in vitro antibody production to influenza virus.

To study HLA class II compatibility requirement for in vitro antibody production to influenza virus, semipurified T lymphocytes, B lymphocytes and monocytes from HLA-typed responder donors were used. The presence of the three subpopulations was required for antibody production while a mixture of only two of those was ineffective. When using fresh T lymphocytes which exert an allogeneic suppressive effect and may also exhibit allogeneic helper activity, it was not possible to conclude an HLA class II-linked restriction of T-B cell cooperation although there was a suggestion of it. However, a grown H3 hemagglutinin-specific T cell line (L2), previously shown to be restricted by HLA-DR molecule (DR1) for interaction with antigen-presenting cells and devoid of allogeneic reactivity, exerts an HLA class II-restricted helper activity. This was demonstrated by various combinations of HLA-DR semi-compatible or incompatible B lymphocytes and/or monocytes with L2 T cells. The restriction element was identified as an HLA-DR determined since HLA-DC-compatible, HLA-DR-incompatible B lymphocytes were not helped by L2 T cells. In addition, monoclonal anti-HLA-DR but not anti-HLA-DC antibodies directed to the relevant specificity did inhibit the antigen-specific helper activity. We present evidence that not only T monocyte but also T-B and/or T-B-monocyte interactions are HLA class II restricted.

Antibodies, Viral↗
PubMed1985

Correlation of the chemiluminescence-activity of peripheral blood monocytes with CSF parameters of inflammation and the clinical course of patients with lymphocytic meningoencephalitis.

The chemiluminescence-activity (CL-A) of peripheral blood monocytes (MO) was measured in eight patients with lymphocytic meningitis or meningoencephalitis and compared to CSF parameters and the clinical course. The initial maximum CL-A was around four times above the control and decreased to normal values within approximately 20 days. Poor correlations were found when the CL-A was compared to CSF parameters in the total group of patients. With regard to the CSF parameters in individual patients the CL-A was closely related to the cell count, to a lesser degree to the protein content, but not to the IgG content. Finally, a very good correlation of the CL-A was found with the clinical course in individual patients. This preliminary data suggests the clinical usefulness of CL-measurements and supports the conception that the CL-A predominantly reflects the specific cellular phase of inflammation, which is dominated by T cells.

Adolescent↗
PubMed1985

Drug-induced agranulocytosis: evidence for the commitment of bone marrow haematopoiesis.

Clinical and haematological features of 61 patients with drug-induced agranulocytosis (63 episodes) are presented. Multiple drug consumption was a common observation and complicated the attempt to incriminate a particular drug as being aetiologically involved. Bone marrow analysis shortly after the diagnosis revealed evidence for an impairment of proliferative granulopoiesis in the majority of cases. This observation was confirmed by in vitro culturing of granuloid precursor cells (CFU-c). Moreover, the data clearly demonstrated that drug-induced agranulocytosis may not be restricted to the granulocytic series. Thrombocytosis and reticulocytosis during the recovery phase are taken as an indication for the commitment of all haemopoietic cell lineages in agranulocytosis. These observations were in accordance with cytomorphological studies and in vitro culture data of erythroid precursor cells (CFU-e, BFU-e) of bone marrow aspirates taken in the initial phase of agranulocytosis. More than 25% of the patients showed a marked erythroid depression in the marrow.

Adolescent↗
PubMed1985

Deficiency of the adhesive protein complex lymphocyte function antigen 1, complement receptor type 3, glycoprotein p150,95 in a girl with recurrent bacterial infections. Effects on phagocytic cells and lymphocyte functions.

A patient presenting delayed umbilical cord detachment, severe recurrent bacterial infections, and inability to form pus exhibited a profound defect in the expression of alpha- and beta-chains of the receptor for the C3bi fragment of C3 (CR3), lymphocyte function antigen 1 (LFA-1) molecule, and the p150,95 molecule found on neutrophils, monocytes, and lymphocyte membranes. This was shown by immunofluorescence studies using specific monoclonal antibodies, rosette formation with C3bi-coated erythrocytes, and immunoprecipitation for the LFA-1 complex. These membrane defects were responsible for abnormal phagocytic cell functions including adherence to nylon wool, cell movement, phagocytosis, and opsonized particle-induced oxidative response and for defective natural killer cell activity. In addition, lymphocyte function deficiencies previously unobserved in this disease were found. Cytolytic T lymphocyte activity was profoundly reduced; alpha- and gamma-interferon production were impaired. Finally, there was no antibody production to vaccinal antigens whereas the antibody responses to polysaccharides and to cytomegalovirus were found to be normal. The cytotoxic T cell deficiency could be expected from previous blocking experiments of this function with monoclonal antibodies to LFA-1 and is probably related to an extremely severe deficiency in LFA-1 expression in this patient. Anomalies in interferon and in antibody production suggest additional role(s) of the LFA-1 complex in monocyte/T lymphocyte/B lymphocyte cell interactions that have not yet been envisaged.

Antibodies, Monoclonal↗
PubMed1985

Separation of a population of human T lymphocytes that bind prostaglandin E2 and exert a suppressor activity.

Prostaglandin E2 (PGE2) is a potent inhibitor of immune functions. Two possible mechanisms of PGE2-mediated suppression have been proposed: one is a direct inhibitory effect exerted on interleukin 2-producing T cells; the second is mediated by the activation of nonspecific suppressor T lymphocytes. We previously showed that PGE2 can directly activate human T lymphocytes to suppress lymphocyte proliferation and B lymphocyte maturation. Herein is described the binding of 10 to 30% of human peripheral blood T lymphocytes to insolubilized PGE2 coated to albumin-Sepharose. The T lymphocytes that bound PGE2 (PGE2(+] could be eluted by the addition of serum and gentle shaking of the beads. The following data indicated the specificity of the binding: i) T lymphocytes after an overnight incubation, a condition known to abolish sensitivity to PGE2, lost their affinity for PGE2; ii) preincubation of T lymphocytes with PGE2 blocked the binding; iii) PGE2(+) T cells bound PGE after a 24-hr incubation, whereas PGE2(-) T cells did not. Few T cells bound albumin, and only a small percentage (7 to 9%) bound 6-keto-prostaglandin F1 alpha-coated beads. Among PGE2(+) T cells, there was a slight increase in the percentage of OKT8+ cells. Although T cells that had no affinity for PGE2 (PGE2(-] proliferated as well as unseparated T lymphocytes when stimulated with mitogens or antigens, the proliferative response of the PGE2(+) subset was poor. Moreover, PGE2(+) T lymphocytes did exert a strong suppressor activity on mitogen- or allogeneic cell-induced lymphocyte proliferation as well as on pokeweed mitogen-driven B cell maturation into Ig-containing cells. PGE2(-) T lymphocytes were shown not to exert a significant suppressor activity in these assays. The PGE2(+) subset-mediated suppression was not secondary to a carry-over of PGE2 released from the beads, because its suppressor activity was not altered by the addition of an anti-PGE2 serum. Moreover, PGE2(-) T lymphocytes were not sensitive to the inhibitory activity on cell proliferation of PGE2. These results indicate that a given functional subset of peripheral blood T lymphocytes binds PGE2, and that at least some of them are activated into suppressor T cells. The relationship between the PGE2-activatable T suppressor subset and other functionally defined suppressor T cells remains to be clarified; it is suggested, however, that PGE2 can act as an immunoregulator through the activation of identifiable suppressor T cells.

Antibodies, Monoclonal↗
PubMed1985

[Severe combined immune deficiency with hypereosinophilia. Immunologic study of 5 cases].

We herein report five new cases of severe combined immunodeficiency with hypereosinophilia, the so-called familial reticuloendotheliosis first described by Omenn. It is characterized by erythroderma, polyadenopathy, hepatosplenomegaly, severe and repeated infections, protracted diarrhoea with failure to thrive. There is marked eosinophilia as well as a profound immunodeficiency. The immunologic abnormalities consist of an increase in T cell number, a B cell lymphopenia and a complete lack of humoral and cellular immune responses to antigens. A deficiency of lymphocytes 5'-nucleotidase has been inconstantly found. Histologic findings are characteristic, consisting of severe T and B lymphocyte depletion in lymphoid organs with infiltration by histiocytes and, to a lesser extent, eosinophils. The outcome was uniformly fatal within the first year of life. Treatment by a combination of parenteral nutrition, steroids and epipodophyllotoxin was effective in obtaining the complete remission of clinical manifestations due to the histiocytic and eosinophilic infiltration in two patients. However, the treatment failed to correct the immunologic defect. These results indicate that the histiocytic infiltration is possibly not responsible for the immunologic detect observed in this condition.

5'-Nucleotidase↗
PubMed1985

[LAV virus infections in children].

The clinical signs and immunological abnormalities in ten babies with lymphadenopathy associated virus infections (LAV) are described. We have made this diagnosis based on the association of specific immunological abnormalities, serological tests or the positive isolation of the virus. In one very severe case, whose mother died of AIDS, the serology and attempts to isolate the virus were both negative. Excluding the two post-transfusion cases, the ethnic and familial history always suggested the diagnosis. The clinical characteristics were very close to those in adults, being hepatosplenomegaly and generalized lymphadenopathy. There was an associated retardation of growth and weight gain. A decrease of the absolute number of OKT4(+) lymphocytes and hypergammaglobulinaemia were the abnormalities most frequently observed. The degree of immunodeficiency, both humoral and cellular was very variable. The existence of LAV infection during the first few months of life suggests a maternal-foetal transmission, but a post-natal infection cannot be eliminated. It is difficult to decide the long-term prognosis; it depends mainly on the degree of the immune deficiency.

Acquired Immunodeficiency Syndrome↗
PubMed1985

[Aspergillus infection and chronic septic granulomatosis].

Chronic granulomatous disease of childhood is a hereditary abnormality of phagocytic cells, frequently associated with Aspergillus infections. From 1969 to 1984, 14 of 37 children with chronic granulomatous disease have presented with pulmonary (13 cases) and/or osteo-articular (1 case) aspergillosis. The paucity of symptoms was a characteristic of these infections. Lung lesions extending to the thoracic chest wall carried the bad prognosis. Neither the Aspergillus skin test nor the Aspergillus serology could definitely confirm the diagnosis. Only broncho-alveolar lavage and biopsy with isolation of Aspergillus could confirm the diagnosis. Long-term therapy with amphotericin B alone or associated with other antifungal agents is necessary. For the past 3 years, ketoconazole prophylaxis has been used in 23 children and none of these children has developed aspergillosis.

Adolescent↗
PubMed1985

Treatment of four patients with erythrophagocytic lymphohistiocytosis by a combination of epipodophyllotoxin, steroids, intrathecal methotrexate, and cranial irradiation.

Familial erythrophagocytic lymphohistiocytosis, a rare disorder affecting infants, is characterized by a visceral infiltration of histiocytes and lymphocytes resulting in rapid death. It has recently been reported that use of epipodophyllotoxin, VP 16-213, could induce a complete remission of the disease. Such treatment does not, however, prevent fatal CNS relapse. Four patients with the characteristic features of the disease--fever, hepatosplenomegaly, pancytopenia, low plasmatic fibrinogen level, hyperlipidemia, and histiocytic meningitis--are described. These patients were treated with a combination therapy including systemic administration of VP 16-213, steroids, and intrathecal methotrexate followed by cranial irradiation after the age of 12 months. The four patients achieved complete remission of the disease after clearing of the CNS localization. Two patients had secondary relapses, but all four patients have had a disease-free survival exceeding 12 months. All patients have been in remission of the disease for 27, 20, 16, and 13 months, respectively, after disease onset without major setbacks from the treatment. This combination therapy appears to be a promising approach toward long-term remission of the disease.

Antineoplastic Combined Chemotherapy Protocols↗