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G Ricevuti

Publications and source records attributed to G Ricevuti.

134 records · Page 8Linked to original sources
PubMedDate not supplied

[Contents of nuclear Feulgen-DNA in carcinoma of the breast. Cytophotometric analysis].

The frequency distributions of the nuclear Feulgen-DNA, obtained with cytophotometric technique, in different types of female mammary carcinomas (invasive ductal carcinoma, papillary and mucinous ductal carcinomas and invasive lobular carcinoma) were correlated with the histological diagnoses and with the age of the patients. The highest and broadly scattered values of nuclear Feulgen-DNA content, in agreement with the cytomorphologic pictures, were observed in the invasive ductal carcinomas, above all in the youngest subjects (values from 2c to 16c). Papillary and mucinous ductal carcinomas from subjects of the same age, showed lower values; the cases of invasive lobular carcinomas exhibited more homogeneous values with a higher number of cells in the 2c region. The tissue with histological normal patterns showed 2c values of Feulgen-DNA contents with some values near 4c. The general situation point out a different complexity of the tumor population which can be related to a mosaic composition and/or to a multifocal origin with presence of cycling, non-cycling, euploid, aneuploid and polyploid fractions. Then, the Feulgen-DNA content can be correlated to the tumor type and the patient age; it is useful for diagnostic and prognostic problems in the oncological field.

Adult↗
PubMedDate not supplied

Leukocyte CD11/CD18 integrins: biological and clinical relevance.

The integrin family consists of a series of related alpha beta heterodimers (subunits of 95,000-200,000 Mw) involved in a variety of cell-matrix and cell-cell adhesion functions. Leukocyte adhesion has biological importance in numerous processes involving host defense. The CD11/CD18 integrins are differentiated antigens which play a critical role in this mechanism. CD11a/CD18 are apparent on early progenitors of all myeloid and erythroid cells. CD11b/CD18 and CD11c/CD18 are more restricted antigens normally expressed on monocytes, macrophages, PMN and natural killer cells. Activated granulocytes and monocytes express far more CD11b/CD18 than the other two antigens: 6 to 8 x 10(5) CD11b/CD18 molecules appear on maximally activated granulocytes. These integrins and in particular the beta 2 subunit are lacking in a genetic disease. On the other hand, they are fundamental in numerous physiological processes and in various hematological and cardiovascular diseases. The biochemical characterization and behavior of the CD11/CD18 complex in various clinical conditions are the subject of this review.

Adult↗
PubMedDate not supplied

[The effect of opioid peptides on peripheral blood granulocytes].

Some neuropeptides may influence various functions of immunocompetent cells. Endogenous opioids have been implicated in the correlation of the immune, endocrine and nervous system. The object of our study was to evaluate the effects induced by some agonist and antagonist endogenous peptides to opioid receptors on granulocytes (PMNs) functions in vitro. We used these drugs: D-Ala2-D-Leu6-enkephalin (DADL-Sigma-Chemical-Usa); D-Ala2-N-ME-Phe4-Gly-ol5-enkephalin (DAGO-Sigma-Chemical-Usa); Dynorphin 1-9 (Sigma Chemical-Usa); naloxone (Sigma Chemical-Usa) and morphine (Sifac-Italy). Morphine was able to inhibiting neutrophil granulocyte chemotaxis induced by serum activated with E. Coli (p < 0.01), by casein (p < 0.01 and <fMLP (p < 0.01). Furthermore morphine and 1-9 dynorphin inhibited spontaneous migration of PMNs both when added to the upper compartment together with cells. Naloxone was able to inhibit PMNs chemotaxis induced by serum, casein and fMLP, this drug was not able to behave on chemokinesis or random migration activity. Morphine was found to inhibit PMNs aggregation induced by PHA (0.01), PMA (0.01), fMLP (0.01) and Ca++ ionophore (p < 0.01), ATP release (p < 0.01), thromboxane B2 (TxB2) and leukotriene B4 (LTB4) secretion during cell aggregation. Dynorphin 1-9, per sé, induced TxB2 and LTB4 secretion from PMNs. Morphine inhibition of both cell aggregation and ATP release, but not arachidonic acid metabolism product secretion, was prevented by naloxone. The naloxone sensitive impairment by morphine of CD 11/CD 18 complex surface expression observed could play a role in opioid inhibition of PMNs activation.

Adult↗
PubMedDate not supplied

[The role of the granulocytes in ischemic cardiopathy].

Recent studies suggest that granulocytes (PMNs) play a role in the pathogenesis of acute and chronic myocardial ischemia and extension of myocardial injury. Granulocytes can release a variety of mediators tissue injury and synergize with these different mediators, cytokines and other cells resulting in amplification of neutrophil stimulation and rising to additional products with enhanced endothelial injury. Free radicals released by PMNs during ischemia or reperfusion produce deleterious effects on cell membranes, endothelial cells and myocardium. Experience in humans shows the modification of PMNs function in angina and during myocardial ischemia: upon reperfusion PMNs accumulate and produce an inflammatory response leading to endothelial injury. Rabbit derived antiserum dependent-reduction of circulating PMNs in the dog or using monoclonal antibody anti-CD11b/CD18 of PMNs resulted in smaller myocardial infarction. Another aspect of PMNs function is related to leukotriene C4 release; the vasoconstrictor effect of this leukotriene on coronary arteries is synergistic with that induced by platelet-released thromboxane A2, and the decrease in coronary flow produced by the combination of both substances is greater than the sum of changes caused by the two eicosanoids separately administered. The potential role of leukocytes, oxygen radicals, leukotrienes and granulocyte enzymes in the pathophysiology of myocardial injury due to regional ischemia and reperfusion is an area of intense investigation. This overview will not attempt to be exhaustive. Experimental and clinical studies to elucidate these events should not only provide insight into acute and chronic pathologic tissue damage, but may also lead to the identification of important new targets of pharmacologic intervention.

Acute Disease↗