Biomedical subjects

G Piazzolla

Publications and source records attributed to G Piazzolla.

24 records · Page 2Linked to original sources

PubMed1998

Modulation of cytoskeleton assembly capacity and oxidative response in aged neutrophils.

Several reports have emphasized that aged polymorphonuclear cells (PMN) exhibit an impairment of superoxide anion (O2-) generation when triggered with formyl-methionyl-leucine-phenylalanine (FMLP) in comparison to the younger counterpart. Since microfilaments and microtubules are involved in PMN-mediated functions, in a group of old donors we assessed the effects of either actin stabilizing and disrupting agents, i.e. phalloidin and cytochalasin B, or microtubule stabilization or disruption by taxol and colchicine, respectively, on FMLP-triggered neutrophil oxidative responsiveness. Results show that phalloidin treatment, at a concentration ranging from 10(-6) to 10(-8) M, gave rise to an inhibition of O2- release by aged PMN, while the same effect was seen in similarly treated young cells at a concentration of 10(-7) M only. On the contrary, cytochalasin B pretreatment led to an enhancement of O2- generation in both young and aged neutrophils, even if to a lower extent in the latter group. At the same time, taxol at 10(-8) M strength inhibited young cell responsiveness, while no effects were induced by colchicine treatment. Quite interestingly, elderly neutrophil function was negatively modulated by both microtubule affecting compounds. Altogether, these findings suggest the possible relevance of cytoskeletal affecting compounds in the modulation of FMLP-stimulated O2- release during senescence.

Actins↗

PubMed1997

In vitro effects of recombinant human granulocyte-macrophage colony-stimulating factor (RhGM-CSF) on polymorphonuclear cell (PMN) and monocyte (MO) functional capacities in ovarian cancer patients versus human volunteers.

Human polymorphonuclear cells (PMN) and monocytes (MO) from four ovarian cancer patients and seventeen normal donors were in vitro pretreated with different concentrations (25, 50 and 100 IU, respectively) of rhGM-CSF. Phagocytosis and killing of PMN and MO as well as PMN polarization were evaluated in cancer patients before treatment (T0) and at the end of each chemotherapeutic cycle (T1, T2, T3 and T4, respectively) in comparison with normal donors. RhGM-CSF did not affect phagocytosis and killing of PMN and MO. On the other hand, this cytokine was per se endowed with the capacity to enhance PMN polarization in both cancer patients (at T2 interval) and normal donors.

Aged↗

PubMed1997

CD45RA and CD45RO isoform expression on intrahepatic T-lymphocytes in chronic hepatitis C.

A liver tissue recruitment of antigen-specific cytotoxic cells has been reported in chronic hepatitis C virus (HCV) infection, but whether they really play a role in viral clearance is still a matter of investigation. To further evaluate T-cell involvement in HCV-induced hepatic disease, the authors analysed, in a cohort of chronic hepatitis C patients, the intrahepatic T-cell expression of CD45 isoforms by using specific monoclonal antibodies. Within hepatic specimens, CD45RA+ (naive) cell frequency at the portal tract level was significantly higher than that exhibited at lobular level. At the same time, a large number of CD45RO+ (memory) cells was found at periportal sites in comparison with the lobular counterpart. The evaluation of CD45RA and CD45RO isoform topographical distribution in relation to CD4+ and CD8+ lymphocytes, as determined on serial sections, showed that CD45RA antigen expression was predominantly coexpressed with CD4+ lymphocytes at the portal tract level, and the CD45RO phenotype with CD8 structure at the lobular and periportal sites. The levels of CD45 isoforms did not show any correlation with biological and/or histological disease activities. The results suggest that a liver recruitment of both naive and memory cells occurs during chronic HCV infection, even if their functional role needs to be further clarified.

Adolescent↗

PubMed1996

Effects of interferon-alpha treatment on neutrophil oxidative metabolism, lymphocyte proliferation and monocyte HLA class I antigen expression in patients with chronic hepatitis C.

Polymorphonuclear cell (PMN) oxidative metabolism, lymphocyte polyclonal proliferation and monocyte HLA class I antigen expression were evaluated at different intervals of time in patients with chronic hepatitis C (CH-C) subjected to a 6 month interferon alpha (IFN-alpha) treatment and divided into Responder ('R') and Nonresponder ('NR') subsets according to clinical outcome. Before therapy, all subjects exhibited multiple immune alterations even if to a different extent between 'R' and 'NR' subsets: an elevated superoxide anion (O2-) generation by suspended PMN, a failure to further increase neutrophil oxidative responsiveness under adherence conditions, an augmented phytohaemagglutin-induced lymphocyte proliferative capacity and an enhanced HLA class I antigen expression on CD14+ cells. IFN-alpha administration gave rise to a modulation of oxidative response in 'R' group only, since these individuals displayed an O2- release by suspended and adherent PMN which fell within normal values. At the same time, a decrease of lymphocyte proliferation occurred in both groups of patients during IFN-alpha therapy, even if it reached statistical significance in 'R' group only. Finally, a more marked difference between 'R' and 'NR' individuals was noted in terms of HLA class I antigen induction on CD14+ cells at the end of therapy, as a consequence of a reduced expression of these structures in 'NR' subjects. Altogether, these findings suggest the occurrence of a strict relationship between immunoresponsiveness and IFN-alpha induced therapeutical effects in CH-C patients.

Adult↗

PubMed1996

Lipopolysaccharide-, granulocyte-monocyte colony stimulating factor and pentoxifylline-mediated effects on formyl-methionyl-leucine-phenylalanine-stimulated neutrophil respiratory burst in the elderly.

The impairment of superoxide anion (O2-) generation by aged polymorphonuclear cells (PMN) stimulated with formyl-methionyl-leucine-phenylalanine (FMLP) has been reported. In this work the effect of lipopolysaccharide (LPS), granulocyte-macrophage colony stimulating factor (GM-CSF) and pentoxifylline (POF) pretreatment on FMLP-triggered neutrophil oxidative metabolism in a group of healthy elderly individuals, was investigated. Results provide evidence that LPS and/or GM-CSF priming was able to enhance O2- production in old PMN, even if values were still lower than those observed in similarly-treated young cells. Moreover, even if the lag period was unaffected by inflammatory mediator treatment, the priming gave rise to a significant increase of maximum O2- release rate. On the contrary, POF pretreatment led to a significant decrease of oxidative responsiveness in either unprimed or primed PMN suspensions. These findings suggest the occurrence of different mechanisms in the imbalance of FMLP-activated neutrophil oxidative responsiveness during senescence. This may be of paramount significance for explaining the augmented frequency of severe infectious diseases with advancing age.

Aged↗

PubMed1989

Psychologic factors in chronic headache: assessment by means of the SCL-90-R inventory.

A survey of the psychologic profile of 540 chronic headache cases, including migraine, tension, and mixed headache, has been carried out with the symptom check list (SCL)-90-R inventory. The results obtained were viewed in relation to sex, age, illness onset, and illness duration. Females showed a positive correlation of somatization with present age and with age at onset of illness and a negative correlation of interpersonal sensitivity, hostility, and paranoid ideation with present age and age at onset of illness. Men showed a negative correlation of obsessive-compulsive and paranoid scores with age and a positive correlation between onset of illness and somatization. Data were also analyzed by cluster analysis, which showed underpopulation with peculiar patterns of symptom profile. A prospective, long-term epidemiologic study could provide more conclusive results.

Adult↗