Search PubMed⌕ Search

Biomedical subjects

G Ricevuti

Publications and source records attributed to G Ricevuti.

At least 55 records · Page 3Linked to original sources
PubMed1990

Peptide opioids and morphine effects on inflammatory process.

Morphine was found to inhibit human granulocyte aggregation and ATP, thromboxane B2 (TxB2), and leukotriene B4 (LTB4) secretion during cell aggregation. None of the opioid peptides tested [(D-Ala2, D-Leu5)-enkephalin (DADL), (D-Ala2, N-Me-Phe4, Gly-ol5)-enkephalin (DAGO) or dynorphin 1-9 (Dyn 1-9)] was capable of mimicking morphine effects, while Dyn 1-9 per se induced TxB2 and LTB4 secretion from granulocytes. Morphine inhibition of both cell aggregation and ATP, but not of arachidonic acid metabolism product secretion, was prevented by naloxone. The naloxone-sensitive impairment by morphine of CD11b-CD18 complex surface expression observed could play a role in opioid inhibition of granulocyte activation.

Adenosine Triphosphate↗
PubMed1990

Increased neutrophil aggregability in coronary artery disease.

The purpose of this investigation was to study neutrophil (PMN) aggregation in the aorta and coronary sinus of 20 patients with angiographically documented coronary artery disease (group I) compared with eight patients with normal coronary arteries (group II). PMNs were separated from the other blood components and their aggregation response to Ca2+ ionophore A 23187 l x 10(-5) M (final concentration) was measured. Group I patients had higher aggregating activity in the coronary sinus than in the aorta (24.9 +/- 3.7 vs 18.7 +/- 3.4 average maximum delta T, P less than 0.01), while no difference was found in group II (coronary sinus 16.7 +/- 3.5; aorta 16.3 +/- 2.4 average maximum delta T P = NS). Among group I patients, smokers had a significantly higher aggregating activity than non-smokers, whereas no correlation was found between aggregation response and blood cholesterol values. These data suggest that the presence of atherosclerotic plaques in coronary vessels may prime PMNs so that they show greater aggregating response to subsequent stimulation.

Aorta↗
PubMed1990

Surface expression of CD11b/CD18 of pseudo-Pelger granulocytes in chronic myeloid leukaemia.

The aim of the present study was to evaluate the surface membrane glycoproteins of pseudo-Pelger granulocytes in six patients suffering from chronic myeloid leukaemia (CML). We studied the functional and immunochemical activities of five monoclonal antibodies (MoAb) minimally reactive with integrin familial antigens of pseudo-Pelger granulocytes. The study conducted with cytofluorimetric and immunological alkaline phosphatase anti-alkaline phosphatase (APAAP) analysis showed a decreased expression of CD11b/CD18 detected by antibodies OKM1, 60.1 and 60.3 (P less than 0.001). Lymphocyte function associated antigen (LFA-1) was expressed in normal amounts in pseudo-Pelger granulocytes. There was decreased expression of CD11b/CD18 in pseudo-Pelger granulocytes with respect to controls (P less than 0.001) after stimulation with formyl-met-leu-phe (FMLP). We conclude that acquired pseudo-Pelger granulocyte dysfunction may be correlated to decrease of surface glycoprotein expression of CD11b/CD18.

Aged↗
PubMed1990

Granulocyte activation after coronary angioplasty in humans.

To determine whether percutaneous transluminal coronary angioplasty (PTCA) would lead to neutrophil activation with subsequent discharge of proteolytic enzymes, like elastase, and oxygen free radicals, like superoxide anion, blood samples were taken from the coronary sinus and aorta in 14 patients with stable angina and one-vessel disease who underwent PTCA. Neutrophils were separated by means of the Ficoll-Hypaque system and were stimulated to detect release of elastase and generation of superoxide anion. Plasma levels of elastase were also measured by an immunoenzymatic method. PTCA was successful in all patients. Plasma elastase levels increased significantly at the end of the procedure compared with pre-PTCA values both in the coronary sinus (from 129.2 +/- 16.6 to 286.6 +/- 39.7 micrograms/l, p less than 0.005) and in the aorta (from 117.4 +/- 13.6 to 258.1 +/- 41.3 micrograms/l, p less than 0.005). On the other hand, superoxide anion released in the supernatants after neutrophil stimulation by phorbol-myristate-acetate decreased after PTCA in the coronary sinus (before PTCA, 60.1 +/- 7.1; after PTCA, 40.7 +/- 6.8 nmol 1 x 10(7) granulocytes/ml/15 min, p less than 0.05), whereas a mild but not significant decrease was observed in the aorta (from 58.3 +/- 10.9 to 55.3 +/- 8.6 nmol 1 x 10(7) granulocytes/ml/15 min, p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

In vivo and in vitro HeNe laser effects on phagocyte functions.

The goal of this work was to evaluate the effect of helium-neon (HeNe) laser irradiation on immunocompetent cells. We used the in vivo skin window method and in vitro granulocyte function tests. The study of cellular migration showed a marked decrease in vitro and in vivo in a dose-independent manner. Superoxide release was not modified by laser irradiation. The granulocyte's aggregation, when using PHA and PMA, presented a reduction that was statistically very significant, not as a subordinate dose. An increase of the release of ATP was demonstrated only at 4 joules and precedes granulocyte aggregation. When using Ca2+ ionophore A23187 as stimulus, laser irradiation at 1, 2 or 4J did not show any modification of granulocyte aggregation. The monoclonal antibody 60.1, which identifies a membrane antigen fundamental for aggregation and chemotaxis, is expressed in normal amounts on granulocyte membranes both before and after irradiation with a HeNe laser. In fact, Laser irradiation preferentially attacks the area of the cellular centrosome that determines a modification of cellular morphology. The electron microscope and immunofluorescence study with a monoclonal antibody have pointed out a disorganization of the microtubules. The alteration of some of the granulocyte functions is correlated to the damage in the centrioles. The granulocyte mitochondrial system and surface membrane remain intact, and this explains the normal production and release of free radicals. Further experiments are necessary to evaluate the clinical application of lasers in various diseases with immunophagocytic pathogenesis.

Adenosine Triphosphate↗
PubMed1989

Effect of piroxicam therapy on granulocyte function and granulocyte elastase concentration in peripheral blood and synovial fluid of rheumatoid arthritis patients.

The effect of piroxicam therapy (20 mg/day for 15 days) on various polymorphonuclear granulocyte (PMN) responses and on PMN elastase concentration was investigated in nine patients with active rheumatoid arthritis. Peripheral blood and synovial fluid samples were collected before starting therapy and 12 h after the last dose of the drug. All patients were evaluable for peripheral blood analysis and six for synovial fluid analysis. Piroxicam therapy had no effect on PMN random migration and phagocytosis, while it significantly reduced both FMLP-induced aggregation and FMLP-induced chemotaxis. This seems mainly due to an effect on FMLP binding, as no differences were observed after therapy in PMA- and PHA-induced aggregation as well as in serum-induced chemotaxis. In contrast, a marked impairment of NBT test and PMA- and FMLP-induced superoxide anion (O2-) production was found after piroxicam therapy. This effect was as evident in peripheral blood as in synovial fluid PMN. Also, a significant reduction in synovial fluid PMN number and synovial fluid PMN elastase concentration (elastase-alpha 1-proteinase complex) was found after treatment. It is concluded that piroxicam may act at different sites on various PMN responses. Its effect on O2- generation and PMN elastase concentration in synovial fluid may have an important role in reducing destruction of arthritic joint tissue.

Adult↗
PubMed1989

New trends in coronary artery disease: the role of granulocyte activation.

Circulating granulocytes play an important role in microvascular perfusion and organ pathology. Oxygen radicals released by aggregated and activated neutrophils may exacerbate the tissue damage caused by ischemia. We studied neutrophil aggregation and oxygen metabolites release in 16 patients suffering from coronary artery disease and in 6 control subjects in aorta and coronary sinus blood samples. The neutrophil aggregation (P less than 0.01) and oxidase activity (P less than 0.01) are higher in coronary sinus than aorta samples only in the patients with respect to controls. While the superoxide generation is decreased in coronary sinus (P less than 0.05). Our aggregation assay supported the potential role of granulocytes in neutrophil-endothelial interactions and tissue damage, and our results about oxidase activity and superoxide release suggested the potential role for neutrophil-derived oxygen radicals in the pathogenesis of vascular injury in vivo.

Calcimycin↗
PubMed1989

A stereoselective blockade by naloxone of opioid and non-opioid-induced granulocyte activation.

Naloxone was found to prevent both opioid and non-opioid-induced migration of human granulocytes in a stereoselective way. Indeed, besides being able to inhibit morphine-induced migration, (-) but not (+), naloxone isomer proved to abolish either casein, serum of fMLP-induced chemotaxis. It is concluded that opioid-induced modulation of granulocyte migration is likely to be mediated through specific receptors, possibly of the mu type. Moreover, the antichemotactic effect of naloxone suggests an involvement of opioid receptors and/or endogenously released opioids in the mechanism of granulocyte activation by different chemoattractants.

Chemotaxis, Leukocyte↗
PubMed1989

Definition of CD 11a, b, c, and CD 18 glycoproteins on chemotactically deficient granulocyte membranes in patients affected by myeloid disorders.

We studied neutrophil chemotaxis and surface membrane glycoproteins in 12 patients suffering from myeloid disorders with abnormal karyotype using in vitro techniques in all 12. Chromosome studies were also carried out virtually simultaneously. We chose to study only patients showing a deficit of chemotaxis (p less than 0.001). Ten of these patients revealed a clonal chromosome abnormality in most of the leukemic cells. The monoclonal antibody technique using MoAb 60.1, 60.3, 60.5, OKM1, LFA-1 and 9E8 demonstrated normal leukocyte membrane glycoproteins CD 11a, b, c and CD 18 and therefore excludes that an abnormality of these is involved in the pathogenesis of altered leukocyte chemotaxis. No correlation between chemotactic deficit and any specific clonal chromosome abnormality was found.

Anemia, Refractory, with Excess of Blasts↗
PubMed1989

The potential malignancy of eccrine spiradenoma.

Eccrine spiradenoma is a rare, usually benign tumor, originating from cutaneous sweat glands. Its clinical and histologic diagnosis can be difficult at times, especially when malignant features are present. Proper management requires radical surgical excision. Two cases of spiradenoma are reported, one of which highly malignant with diffuse pulmonary metastases leading to the patient's death in spite of repeated radical surgery.

Adenoma, Sweat Gland↗
PubMed1989

[In vitro effects of morphine and opioid peptides on neutrophil granulocyte aggregation and ATP release].

The effects of morphine and opioid peptides on neutrophil aggregation and ATP release were studied. Inhibition of human granulocyte aggregation and ATP release was observed in the presence of morphine in a naloxone stereoselective manner, whereas the opioid peptides were ineffective. The effects of DAGO, DADL and Dynorphin 1-9 on the granulocyte aggregation and ATP release were also evaluated, but these opioids peptides are unable to modify neutrophil function. Our studies confirm the role of mu receptors on modulation of polymorphonuclear granulocyte aggregation and suggest a key role of opioid peptides in the regulation of some immune system functions.

Adenosine Triphosphate↗
PubMed1989

[Granulocyte disease caused by glycoprotein complex deficiency correlated with leukocyte adhesion].

This report summarizes the clinical and laboratory findings from a group of our patients and literature reviews from several families who have a genetic deficiency in three related leukocyte membrane surface antigens known as CR3,LFA-1, and p150,95. Each surface antigen has an identical beta-chain noncovalenty linked to one of three distinct alpha-chain types. Patients affected by this autosomal recessive disease have now been identified by several investigators. The patients have an increased susceptibility to bacterial infections that is similar to patients who have other types of neutrophil functional deficiencies or neutropenia. Laboratory tests have indicated that isolated neutrophils from these patients have two major types of functional deficiencies that probably contribute to their reduced ability to overcome bacterial infections. This review focuses exclusively on the phagocytic and cytotoxic abnormalities of neutrophils from these patients.

Antibodies, Monoclonal↗
PubMed1988

Opioid-induced modification of granulocyte function.

Inhibition of human granulocyte chemotaxis towards casein was observed in the presence of both the mu and kappa opioid receptor agonists, which, per se, exhibited chemokinetic activity. Naloxone was found to prevent both the opioid-related and opioid-unrelated increase in granulocyte migration. Moreover, morphine inhibited the aggregation response of granulocytes in a naloxone-sensitive way, while the opioid peptides were ineffective. Although opioid agonists with different receptor specificity were capable of strongly modifying human granulocyte migration, no conclusion can be drawn on the role of opioid receptors in regulating migrating activity. On the other hand, opioid receptor activation by morphine is likely to be responsible for aggregation inhibition.

Adenosine Triphosphate↗
PubMed1988

Influence of erdosteine, a mucolytic agent, on amoxycillin penetration into sputum in patients with an infective exacerbation of chronic bronchitis.

Twenty four patients with acute infective exacerbations of chronic bronchitis received amoxycillin alone or in combination with erdosteine (a mucolytic agent) for a week in a double blind, placebo controlled study. Clinical assessment scores, body temperature, serum and sputum amoxycillin concentrations, and sputum culture results were recorded in each group. Erdosteine significantly increased antibiotic concentrations in sputum but not in serum. The combined treatment also caused a more rapid decrease in sputum viscosity and in body temperature and faster sterilisation of the sputum. These results show that erdosteine increases amoxycillin concentration in sputum in patients with acute exacerbations of chronic bronchitis. This effect may be due to a reduction in the viscosity of the bronchial secretions produced by erdosteine.

Aged↗
PubMed1988

Serum, sputum and bronchial concentrations of erythromycin in chronic bronchitis after single and multiple treatments with either propionate-N-acetylcysteinate or stearate erythromycin.

Serum and bronchial concentrations of erythromycin were determined in 30 chronic bronchitic patients during an exacerbation phase of bacterial infections. The levels were measured after single and multiple oral treatments with erythromycin-propionate-N-acetylcysteinate (EPAC) or erythromycin stearate (ES) in a double-blind design. EPAC showed higher and longer-lasting erythromycin levels in serum, sputum and pure bronchial mucus than ES. It is believed that EPAC is better absorbed because of its greater stability in the gastrointestinal juices. Higher concentrations in bronchial secretions not always depend on the blood levels. It seems to be possible that the N-acetylcysteine moiety in the molecule of EPAC drug can facilitate antibiotic penetration because of its mucolytic activity. The clinical response (disappearance of fever, clearance of bacterial pathogens from sputum, reduction of quantity and viscosity of sputum) also occurred faster in the EPAC than in the ES group.

Acetylcysteine↗