Biomedical subjects

G Colombo

Publications and source records attributed to G Colombo.

At least 145 records · Page 8Linked to original sources

PubMed1991

The effect of cytokines on human neutrophil Fc receptor-mediated phagocytosis.

The recombinant (r) cytokines interferon-gamma (rIFN-gamma), granulocyte/macrophage-colony stimulating factor (rGM-CSF) and tumor necrosis factor-alpha (rTNF-alpha) all activate neutrophils. The aim of this work was to determine the effect of these cytokines on neutrophil Fc-receptor (FcR)-mediated phagocytosis and membrane expression of FcR, particularly FcRII and FcRIII. A short treatment (greater than or equal to 15 min) of neutrophils with rGM-CSF and rTNF-alpha at concentrations greater than or equal to 62.5 U/ml significantly increased their ability to bind and phagocytize IgG-coated erythrocytes (EA). Both cytokines also showed more enhancing activity when suboptimally sensitized EA were used for binding and ingestion assays. A similar treatment of neutrophils with rIFN-gamma at doses up to 500 U/ml was ineffective. The effect of rGM-CSF and rTNF-alpha was blocked by a monoclonal anti-GM-CSF antibody and by a polyclonal anti-TNF-alpha antibody respectively, thus establishing that the cytokines were responsible for the activity of the recombinant preparations. The cytokine-induced enhancement of FcR-mediated phagocytosis did not correlate with an enhancement of FcRII membrane expression on treated neutrophils; rGM-CSF significantly increased FcRIII expression, but rTNF-alpha and rIFN-gamma were both ineffective in this respect. Since different roles of FcRII and FcRIII have been reported on ligand binding and ingestion, we also studied the effect of rGM-CSF and rTNF-alpha on the functional properties of these FcR, using specific monoclonal antibodies (mAbs). In the blocking experiments the pretreatment of neutrophils with rGM-CSF and rTNF-alpha did not modify the blocking properties of either anti-FcRII or anti-FcRIII mAbs, suggesting that cytokine-pretreatment does not affect the individual contribution of each type of FcR to ligand binding and internalization. Our data point to a new activity for both rGM-CSF and rTNF-alpha in augmenting FcR-mediated phagocytosis on neutrophils, but the mechanism of this enhancement remains to be elucidated.

Cell Adhesion↗

PubMed1991

Genetic sensitivity to effect of ethanol on dopaminergic system in alcohol preferring rats.

The effect of ethanol (etOH) on dopamine (DA) metabolism in the caudate nucleus (CN), olfactory tubercle (OT) and medial prefrontal cortex (MPFC) was compared in 2 selectively bred lines of rats, one etOH-preferring (sP) and the other -non preferring (sNP). EtOH (2 g/kg per os), administered 60 min before killing, caused a significant increase in concentrations of the DA metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), and reduced DA levels in CN and OT in sNP rats. On the other hand in sP rats, etOH increased the content of DA metabolites in all the 3 areas analyzed. These changes induced by etOH in DA metabolism were significantly greater in sP than in sNP rats. The above data indicate that sP rats have a genetic high sensitivity to etOH effect on DA metabolism probably linked to etOH preference.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1990

MOv18 monoclonal antibody in diagnostic applications: capability to recognize the histotype of the original tumor.

Cells from 52 ascitic fluids and 28 abdominopelvic cavity washings, obtained from 46 ovarian cancer patients, 17 patients bearing malignancies of non ovarian sites and 17 patients with non-malignant ovarian diseases, were tested using 2 methods: traditional cytology and monoclonal antibody immunofluorescence. The immunologic test using the MOv18 MAb, raised against ovarian carcinoma, revealed immunoreactive cells in 83% of the 36 cytologically positive fluids and in one of the 8 negative fluids from ovarian carcinoma patients and in 18% of the 17 fluids from patients with non-malignant ovarian disease. Forty six cytologically positive ascitic fluids from malignant patients were analyzed in order to evaluate the ability of this MAb to identify the histotype of metastatic cells. Ninety-three percent (26/28) of the effusions from nonmucinous ovarian carcinomas contained MOv18-positive cells, whereas no reactive cells were found in cytologically malignant fluids from patients with ovarian tumors of other oncotypes or with carcinomas of non-ovarian origin. The MOv18 reagent, used as an adjuvant in cytological analysis, can help in the identification of the histotype of metastatic cells of unknown origin.

Adenocarcinoma↗

PubMed1990

Alcohol-preferring rats: genetic sensitivity to alcohol-induced stimulation of dopamine metabolism.

The effect of ethanol on brain dopamine (DA) metabolism in the caudate nucleus (CN), olfactory tubercle (OT) and medial prefrontal cortex (MPFC) was compared in two selectively bred rat lines, one ethanol preferring and the other ethanol nonpreferring. Male rats from the 16th and 17th generations of both lines that never experienced ethanol beforehand were used. No differences in the basal concentrations of DA and its metabolites, DOPAC and HVA, in the above brain regions were found between the two lines. The oral administration of 2 g/kg of ethanol to ethanolnonpreferring rats increased DOPAC and HVA and reduced DA levels in the CN and OT but was ineffective in the MPFC. On the other hand, ethanol administration to ethanol-preferring rats decreased DA content and increased DOPAC and HVA levels, not only in the CN and OT, but also in the MPFC. Moreover, the changes induced by ethanol on DA metabolism in the latter group were significantly greater than in ethanol nonpreferring rats. These results indicate that ethanol preferring rats have a genetic high sensitivity to the ethanol effect on DA metabolism, and suggest that such a trait might play a role in ethanol preference.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1990

Evaluation of different surgical approaches in the treatment of endometrial cancer at FIGO stage I.

From January 1, 1970 to December 31, 1979, 425 cases of endometrial carcinoma, FIGO stage I, were treated at the First Department of Obstetrics and Gynecology, University of Milan. Three different surgical approaches were used: total abdominal hysterectomy with bilateral salpingo-oophorectomy and selective pelvic lymphadenectomy was performed in 245 women, total abdominal hysterectomy and bilateral salpingo-oophorectomy without pelvic lymphadenectomy in 100, and vaginal hysterectomy with bilateral salpingo-oophorectomy in 80. Five-year survival was evaluated as a function of risk factors (histological grade, depth of myometrial invasion, metastatic nodes) in the three groups of patients, and we conclude that lymphadenectomy is useful for prognostic purposes but does not confer a therapeutic benefit.

Adult↗

PubMed1990

Hypercoagulability during L-asparaginase treatment: the effect of antithrombin III supplementation in vivo.

To evaluate the occurrence of hypercoagulability during treatment with L-asparaginase (L-ase), thrombin-antithrombin complex (TAT) and D-dimer levels in plasma were serially measured in 15 consecutive adult patients with acute lymphoblastic leukaemia or lymphoblastic lymphoma who had recently completed a chemotherapy cycle with cytosine arabinoside and methotrexate. The first eight patients (group A) received i.v. L-ase alone (20,000 U/m2 on alternate days over 10 d); the last seven patients (group B) received, in addition to L-ase, bolus injection of antithrombin concentrate (2000 U) on alternate days for a total of six administrations, beginning with the second L-ase infusion. Increased levels of TAT (P less than 0.05) and D-dimer (P less than 0.01) were observed prior to L-ase, possibly related to inflammation and cytolysis secondary to previous chemotherapy. In patients treated with L-ase alone, further elevation of TAT (P less than 0.05) and persistence of increased D-dimer were observed, associated with marked reduction of the anticoagulant activities of protein C, protein S and antithrombin III. At variance, in patients receiving antithrombin III supplementation there was no increase of TAT and a normalization of D-dimer levels occurred during L-ase treatment. In these patients, mean plasma antithrombin III activity was maintained at levels higher than 70% of normal throughout the treatment. The rate of decline of fibrinogen, factor IX, protein C and protein S was unaffected by antithrombin III supplementation, indicating that hypercoagulability has little if any relevance for the reduction of coagulation factors and inhibitors induced by L-ase treatment. The usefulness of antithrombin III concentrates in preventing thromboembolic complications in patients submitted to L-ase treatment remains to be determined.

Antithrombin III↗

PubMed1990

Ro 19-4603, a benzodiazepine receptor inverse agonist, attenuates voluntary ethanol consumption in rats selectively bred for high ethanol preference.

The effect of Ro 19-4603, a novel potent partial inverse agonist of benzodiazepine (BZ) receptors, on voluntary ethanol intake was examined in a rat line selectively bred for ethanol preference (Sardinian ethanol preferring, sP, rats). Ro 19-4603, 1 mg/kg i.p., three times daily, reduced voluntary ethanol consumption by about 40% during 7 days of treatment, but failed to reduce water intake. The results suggest that the GABA/BZ receptor complex may play a role in the reinforcing property of ethanol.

Alcohol Drinking↗

PubMed1990

[Experimental models of alcoholism].

Ethanol causes behavioral effects in rats and mice similar to those observed in humans. Moreover, by selective breeding, lines of rats or mice have been obtained that prefer ethanol solution to water and vice versa (ethanol-preferring and ethanol-avoiding animals). Recent studies suggest that ethanol stimulates GABA receptor-mediated opening of the chloride channels in neuronal membranes, and that some behavioral responses to ethanol, such as its sedative and anxiolytic effects, are mediated by central GABA receptors. Recently, we have shown that ethanol suppresses the firing of neurons in the pars reticulata of the substantia nigra, which exert an inhibitory control over dopaminergic neurons. Escaping from inhibitory control, the latter neurons are stimulated by ethanol. Dopaminergic neurons especially sensitive to ethanol are those of the meso-cortico-limbic system, belonging to the "pleasure centers" of the brain. In addiction, it has been shown that ethanol stimulates dopamine metabolism in different brain areas, but more effectively so in ethanol-preferring than in ethanol-avoiding rats. Finally, voluntary ethanol intake modifies dopamine metabolism in different brain areas.

Alcoholism↗

PubMed1990

Voluntary alcohol drinking increases brain dopamine metabolism in rats.

The effect of ethanol on dopamine (DA) metabolism in two selectively bred lines of rats, one alcohol-preferring (sP) and the other--non-preferring (sNP), was studied. Ethanol administration (2 g/kg per os) produced in the two lines of rats a decrease of DA content and an increased concentration of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the caudate nucleus, olfactory tubercle and medial prefrontal cortex in both lines, but the effect was significantly greater in sP than in sNP rats. Moreover, in sP rats, the voluntary consumption of ethanol increased DOPAC and HVA levels in the above areas. In these animals, DOPAC and HVA accumulation was associated with a small depletion in DA content, suggesting that ethanol releases DA from stores.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1989

Effect of spontaneous ingestion of ethanol on brain dopamine metabolism.

The effect of ethanol, either administered by gavage or voluntarily ingested, on brain dopamine (DA) metabolism was studied in alcohol-preferring and alcohol non-preferring rats. In alcohol non-preferring rats ethanol administration (2 g/kg) increased 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) and reduced DA levels in the caudate nucleus and olfactory tubercle but was ineffective in the medial prefrontal cortex. In alcohol-preferring rats ethanol effect was greater than in non-preferring animals and ethanol influenced DA metabolism also in the medial prefrontal cortex. The effect of voluntary ethanol ingestion was studied in alcohol-preferring rats trained to consume their daily fluid intake within 2 hrs. Voluntary ingestion of ethanol (3.1 +/- 0.7 g/kg in 1 hr) increased DA metabolites and reduced DA levels in the caudate nucleus, olfactory tubercle and medial prefrontal cortex. The results suggest that voluntary ethanol ingestion increases the release of DA from nigro-striatal and meso-limbic DA neurons.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1989

Intellectual impairment and cognitive evoked potentials in myotonic dystrophy.

Twenty-seven patients with myotonic dystrophy (MD) and 20 control subjects were tested using neuropsychological and electrophysiological measures. MD patients reported significantly lower scores on the Wechsler Adult Intelligence Scale and the Mini-Mental State Examination. P3 amplitude of auditory event-related potentials was significantly reduced in 14 patients. P3 latency was normal. In 13 patients, P3 was not elicited. Our results clearly show the presence of a significant impairment of cognitive functioning, as assessed by psychometric measures, in more than 50% of MD patients. Discriminant function correctly classified 92% of patients, using event-related potentials and neuropsychological variables.

Adult↗

PubMed1989

Double-blind placebo cross-over study of long-acting (chlordesmethyldiazepam) versus short-acting (lorazepam) benzodiazepines in generalized anxiety disorders.

Chlordesmethyldiazepam a long-acting benzodiazepine was compared with lorazepam a short-acting one in a double-blind placebo cross-over study against generalized anxiety disorders. Chlordesmethyldiazepam therapy was more effective than lorazepam. Clinical efficacy, drowsiness and insomnia seem well correlated with pharmacokinetic properties of these two benzodiazepines. These results further support the use of a long-acting benzodiazepine rather than a short-acting one as an anti-anxiety agent.

Adult↗

PubMed1989

Synaptonemal complexes analysis in a bull carrying a 4;8 Robertsonian translocation.

Synaptonemal complexes analysis was performed using electron microscopy on surface-spread spermatocytes of a bull heterozygous for the 4;8 Robertsonian translocation. In 19 cells examined, the longest autosomal complex showed kinetochores in a central position whereas the remaining autosomal complexes showed terminal kinetochores. Synapsis in the trivalent appeared complete in all cells, and the trivalents usually showed a CIS configuration. The arm ratio varied from 1.05 to 2.04 with an average of 1.32 +/- 0.43. Out of 47 cells showing X-Y bivalents, 34 showed a small synaptonemal complex at one extremity of the X chromosome, and an unstained gap in the Y chromosome. There was no association between the X-Y bivalent and the trivalent. The absence of association would explain the normal spermatogenesis noted in this bull, in contrast to human and mouse carriers of translocations which show impaired spermatogenesis due to the association between the rearranged chromosomes and the sex vesicle. Further studies involving bulls carrying one or more Robertsonian translocations are needed to determine whether this absence of association is a constant feature in cattle.

Animals↗

PubMed1989

[Chronic T-cell lymphocytic leukemia: clinical and laboratory aspects of 5 patients].

T-cell chronic lymphocytic leukemia: clinical aspects and laboratory findings of five patients. This study illustrates the main clinical aspects and laboratory findings for five patients suffering from T-cell chronic lymphocytic leukemia. They make up 5% of our observations in the Department of Oncology-Hematology at the Busto Arsizio Hospital. Three patients with phenotype CD3+/CD4+ showed a fast course with skin involvement and poor response to chemotherapy (mean survival: 12 months). The course of a patient with unusual phenotype CD3-/CD4+ associated with autoimmune hemolytic anemia and end-stage prolymphocytic transformation was better (survival: 58 months). For 12 years we have been observing a woman suffering from the recently defined CD3+/CD8+/HNK1+ large granular lymphocytes chronic lymphocytosis with associated neutropenia. The disease has good prognosis, with poor symptomatology even without therapy. This study supports the immunological classification of the chronic lymphoproliferative diseases of leukemia and lymphoma with different clinical aspects and prognoses. This method of classification may be important in the consideration of some therapeutical approaches.

Aged↗

PubMed1989

Suppression by gamma-hydroxybutyric acid of ethanol withdrawal syndrome in rats.

The ability of gamma-hydroxybutyric acid to suppress ethanol withdrawal syndrome was tested in male rats rendered physically dependent on ethanol by several intragastric administrations of ethanol (9-15 g/kg daily for 7 days). Gamma-hydroxybutyrate (0.25, 0.50 and 1.00 g/kg i.p.), administered 8 hr after the last ethanol dose, produced a dose-dependent inhibition of withdrawal signs such as tremors and audiogenically-induced seizures; the highest dose tested suppressed all ethanol withdrawal symptoms.

Animals↗

PubMed1988

Depression and neuroticism in multiple sclerosis.

88 subjects (36 males and 52 females) affected by multiple sclerosis (MS), were studied with the CES-D and SRT tests for the evaluation of depressive reactions and neuroticism. Comparing the results with those of the control group, we found a significant score for depression and somatization in the MS patients, whereas the scores for anxiety and inadequacy were normal.

Adult↗

PubMed1988

[Social networks and mental disease].

This is a three-purpose study: (a) Furthering a definition of social network analysis since such a theoretical and methodological approach is of great interest to studying social interaction, (b) Analyzing the social networks within one psychiatric case study in order to build up a network interaction model aiming at fostering future research, this interaction model being used as a concept framework, and (c) Discussing how fruitful research on social networks can prove to be in connection with the treatment of the mentally ill, as well as considering the protective and supportive functions of these networks.

Humans↗

PubMed1988

Pharmacokinetics of benperidol in volunteers after oral administration.

Benperidol in a 4 mg single dose was administered orally to five healthy male volunteers. The drug was rapidly absorbed (tmax = 2.27 +/- 0.57 h) and largely distributed, the volume of distribution being 5.19 +/- 1.99 l.kg-1. Elimination half-life was 7.65 +/- 2.14 h. Urinary excretion represented only a minimal fraction of ingested dose (0.1 +/- 0.007%). Variability of the area under the curve makes a first-pass metabolism a reasonable possibility. Acute dystonias appeared in two subjects.

Administration, Oral↗