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R Adami

Publications and source records attributed to R Adami.

5 recordsLinked to original sources

Involvement of P1-purinoreceptors in the relaxing effect of adenosine in rat duodenum.

1. In isolated segments of rat duodenum, adenosine (50 microM-2 mM) caused a very rapid and short-lasting relaxation that was associated with a marked decrease in the amplitude of spontaneous contractions. 2. Theophylline (0.1-0.8 mM) and 8-phenyltheophylline (1-10 microM) antagonized, in a concentration-dependent manner, the effects of 0.3 mM adenosine on smooth muscle tension and spontaneous activity. 3. The concentration-response curves for adenosine (50 microM-2 mM) were progressively shifted to the right by increasing concentrations of theophylline and of 8-phenyltheophylline, with no change in the maximum effect. 4. 8-Phenyltheophylline (5 microM) did not affect relaxations induced by noradrenaline (0.5 microM) and by isoprenaline (5 nM). 5. These results indicate that the effects exerted by adenosine on rat duodenum are mediated by P1-purinoreceptors.

Adenosine

Erythrocyte lysis by monocytes: investigations on the mechanism and role of the target cell hydrogen peroxide catabolizing pathways.

The erythrocyte (RBC) lysis by human monocytes incubated with opsonized zymosan particles (OPZ), was inhibited by catalase, chloride-free medium, azide and hypochlorous acid (HOCl) scavengers (taurine, alanine). These findings suggest the requirement for the HOCl-generating myeloperoxidase-hydrogen peroxide-chloride system (MPO-H2O2-Cl- system). The HOCl-dependent lysis was increased by inhibiting RBC catalase with aminotriazole (AT). Conversely, the inhibition of RBC glutathione cycle with 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU) had no detectable effect. Moreover, the recovery of H2O2 and HOCl from OPZ-triggered monocytes was reduced by the presence of RBCs through a process almost completely preventable by pulsing RBCs with AT but not with BCNU. Thus, it appears that RBC targets protect themselves by consuming, primarily via catalase, significant amounts of monocyte-derived H2O2 with a consequent impairment of the HOCl generation. The results suggest a potential role of target cells in modulating the cytolysin production by monocytes.

Erythrocytes

Bone marrow transplantation for severe aplastic anemia. A report of 9 cases.

9 patients with severe aplastic anemia (SAA) were treated with bone marrow transplantation (BMT). 5 were conditioned with cyclophosphamide and received and HLA-identical graft (4 patients) or a mismatched graft (1 patient): 1 rejected the graft on day 30 and died on day 34 during conditioning for a second transplant; 1 died on day 15 with acute and severe graft versus host disease (GvHD) in the absence of haemopoietic engraftment; 3 are alive and complete chimeras at 1,069, 490 and 332 days after transplantation. GvHD developed in 4 patients and was treated successfully in 3 with high dose methylprednisolone and/or antilymphocytic globulin (ALG). 4 patients were conditioned with ALG and received bone marrow from a haploidentical sibling or parent: 1 patient was refractory; 3 patients showed evidence of hematologic reconstitution, but 2 of these required a second course of ALG. 3 patients in this group are alive between 60 and 490 days; 1 patient died on day 121 of HBSAg-negative acute hepatitis.

Adolescent