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Biomedical subjects

E Galli

Publications and source records attributed to E Galli.

At least 73 records · Page 4Linked to original sources

Selective inhibition of IgE versus beta 2-microglobulin in human U-266 myeloma cell line treated with T-cell-derived factors.

Concanavalin-A-activated T cells and their crude supernatants were assayed for suppressive activity on an IgE-producing U-266 cell line. Detectable and comparable degrees of suppression were obtained with the co-culture and the supernatant protocols. Separation of the effector population into T4+ and T8+ subsets showed the most effective cells in the T8+ fraction. Control experiments demonstrated that the IgE down-regulation was selective, since parallel measurement of beta 2-microglobulin synthesis showed no effect of T cells or T-cell-derived supernatants. In addition, several human T-cell lymphoma-leukaemia virus I-transformed T-cell lines were explored for their capacity to produce factor(s) able to suppress IgE synthesis in the U-266 cell line, and four out of 25 cell lines could be shown to do this in a constitutive manner. Kinetic studies suggested that the inhibition occurred at a transcriptional level. The results indicate that the T-cell-myeloma system is an interesting model to define better the regulation of IgE in the human.

B-Lymphocytes↗

Purification and characterization of glutamate synthase from Azospirillum brasilense.

Growth conditions for Azospirillum brasilense Sp6 were devised for maximal expression of glutamate synthase. The enzyme levels were largely affected by the type and concentration of the nitrogen source. A 10-fold increase in the synthesis of the enzyme was observed at a limiting concentration of ammonia. The enzyme was purified to homogeneity by a procedure which was fairly rapid and allowed a good recovery of enzyme (30%). Azospirillum glutamate synthase is a complex iron-sulfur flavoprotein with a stoichiometry of 1 flavin adenine dinucleotide:1 flavin mononucleotide:8 Fe:8 S per protomer with a molecular weight of 185,000. The protomer is composed of two dissimilar subunits with molecular weights of 135,000 and 50,000. Kinetic parameters were determined. Km values for NADPH, 2-oxoglutarate, and L-glutamine were 6.25, 29, and 450 microM, respectively. The optimum pH was about 7.5. Complete reduction of the enzyme under anaerobic conditions was obtained either by NADPH (in the presence of a regenerating system) or dithionite or by photochemical reduction (in the presence of EDTA and 5-deazariboflavin). No stable long-wavelength intermediates were observed.

Amino Acids↗

Bone marrow transplantation and thymopoietin pentapeptide treatment in two infants with immunodeficiency with predominant T-cell defects.

Two infants with immunodeficiency with predominant T-cell defects received transplants of HLA-identical bone marrow cells along with thymopoietin pentapeptide (TP-5) treatment and no prior immunosuppressive therapy. Both patients achieved durable engraftment with early reconstitution of cell-mediated immunity. The study of cell surface antigens with monoclonal antibodies (MoAb) revealed that the early appearance of T-cell subsets defined by OKT4 and OKT8 MoAb occurred. Neither of the patients showed any signs or symptoms of graft versus host disease over a 1-year period. This experience suggests that patients with T-cell deficiency who do not benefit from thymic hormones alone can be successfully treated by bone marrow transplantation. The association of TP-5 with bone marrow transplantation seems to induce an early and stable reconstitution and to protect against fatal post-transplant infection.

Antibodies, Monoclonal↗

Molecular characterization of a plasmid from Pseudomonas fluorescens involved in styrene degradation.

In this paper evidence is given that in a strain of Pseudomonas fluorescens able to grow on styrene as the sole carbon source, the degradation pathway of styrene is inducible and plasmid dependent. The plasmid, which we have called pEG is self-transmissible between Pseudomonas strains and has a size of 37 kb. A restriction map has been constructed and evidence for an inducible transcription of two separate regions of the plasmid has been obtained.

Chromosome Mapping↗

Comparison of methods for the biodegradability evaluation of soluble and insoluble organochemicals.

Pyridine and nitrilotriacetic acid sodium salt as models of soluble compounds and linear dodecylbenzene, branched dodecylbenzene, and stearic acid as models of insoluble compounds were compared for their biodegradability in three tests: the ODCE modified test and the Sturm and enrichment culture tests. The degradation of soluble compounds was measured as dissolved organic carbon removal and CO2 evolution, while for the insoluble compounds, which were tested only in the Sturm test, CO2 evolution was determined. The individual tests were characterized by comparing their results with those obtained in the others. Comparable biodegradation values higher than 90% were obtained for the soluble compounds. The Sturm test proved to be very suitable for the evaluation of biodegradability of either soluble or insoluble compounds.

Acetates↗

The microbial oxygenation of the benzylisoquinoline alkaloid laudanosine.

The microbial transformation of the benzylisoquinoline alkaloid laudanosine by a strain of Pseudomonas putida gives a metabolite in which O-demethylation of 1 methoxyl group of ring C, and introduction of 1 ketonic oxygen at C9 and 1 phenolic oxygen at ring C have occurred. Also, O-methylcoripalline is formed in this transformation.

Biotransformation↗

Thymopoietin pentapeptide treatment of primary immunodeficiencies.

26 patients with primary immunodeficiencies (3 infants with severe combined immunodeficiency [SCID] 3 with DiGeorge syndrome, 6 with T-cell defect or SCID with B cells, 4 with common variable hypogammaglobulinaemia and associated T-cell defect, 5 with ataxia-telangiectasia, and 5 with hyper-IgE syndrome) were treated with thymopoietin pentapeptide (TP-5) at a dose of 0 . 5 mg/kg daily for 2 weeks and then 3 times a week at 0 . 5 mg/kg for 10 weeks, 3 patients with DiGeorge syndrome and 3 with primary T-cell defect demonstrated pronounced clinical and immunological improvement during treatment. None of the patients with SCID and 3 of 6 patients with SCID with B cells or primary T-cell defect showed any clinical or immunological changes during therapy. In 5 patients with ataxia-telangiectasia clinical manifestations and immunological tests were unchanged by TP-5. Abnormality of T cells in cases of hyper-IgE syndrome was not corrected by TP-5 treatment.

Adolescent↗

Superoxide-dependent chemotactic activity for PMNs derived from opsonized zymosan-stimulated human platelets.

Previous studies have shown that platelets exhibit a H2O2 producing, NADH-dependent system that is activated by interaction with particulate material. Current evidence suggests that this system could be critically involved in th generation of chemotactic factor(s). In the present studies, chemotactic activity for polymorphonuclear leukocytes of supernatants derived from zymosan-stimulated human platelets has been evaluated using an agarose gel technique. Supernatants of opsonized zymosan-stimulated platelets showed significant chemotactic activity (migration index = 300 +/- 50), in comparison with supernatants prepared from platelet suspensions stimulated with nonopsonized-zymosan (migration index = 10 +/- 15) or resting platelet supernatants (migration index = 15 +/- 15). Furthermore, a marked increase in chemotactic activity of the opsonized zymosan-treated platelet supernatants was demonstrated after the addition of NADH (migration index = 525 +/- 100). The inclusion of specific inhibitors of the cycloxygenase and lipoxygenase pathways resulted in a marked reduction of chemotactic activity, which was restored in the presence of NADH. Further, the addition of superoxide dismutase completely abolished the chemotactic response induced by NADH. These data suggest that platelets are the source of chemotactic factor(s) derived from the activation of a superoxide generating system.

Blood Platelets↗

A case of hyperimmunoglobulinemia E treated with cow's milk and egg-free diet.

This report is of seven-year-old girl with a lifelong history of severe eczema, intestinal features of food allergy, recurrent respiratory tract infections, chronic bilateral keratitis and mucocutaneous candidiasis. Immunological tests showed high serum IgE levels, with specific IgE antibodies to cow's milk and egg white, defective PMN chemotaxis and a marked defect in both the function and number of T-lymphocytes. On a cow's milk-free and egg-free diet the eczema subsided and the respiratory infections improved. A partial correction of the immunodeficiency was also observed. The relationships between the immune system and atopy are discussed.

Animals↗

A child with atopic features, raised serum IgE, and recurrent infection treated with levamisole.

A 6-year-old girl had a long history of severe eczema, asthma, recurrent otitis media, and staphylococcal infections with disseminated chronic skin abscesses. Immunological studies showed a neutrophil chemotaxis defect, hyperimmunoglobulinaemia E, IgE antibodies against cows' milk proteins, absence of IgM, and absence of staphylococcal haemolysins. Neutrophil phagocytic and bactericidal functions and complement system were normal. In the course of treatment with levamisole (2.5 mg/kg, 3 times a week for one year) a striking clinical improvement occurred: the skin lesions and the staphylococcal abscesses gradually cleared and the girl gained weight. There was also a partial correction of the immune deficiency.

Abscess↗