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Biomedical subjects

E Ferrero

Publications and source records attributed to E Ferrero.

At least 73 records · Page 4Linked to original sources
PubMed1985

Murine monoclonal antibodies as probes for the phenotypical, functional, and molecular analysis of a discrete peripheral blood lymphocyte population exerting natural killer activity in vitro.

Two monoclonal antibodies (AB8.28 and A10) reacting with large granular lymphocytes were extensively studied and characterized. The two peripheral blood lymphocyte subsets positive for the expression of AB8.28 and A10 determinants were isolated by cell sorting and the phenotype analyzed using a panel of anti-lymphocyte reagents. Both subsets displayed the characteristics of "null cells." Moreover, these subsets encompassed a significant amount of the natural killer activity, since preparations of peripheral blood lymphocytes deprived of AB8.28+ and A10+ cells showed a remarkable reduction of such activity. The analysis of the distribution of the AB8.28 and A10 epitopes has been carried out using a variety of cells, i.e., normal tissues, tumor cells, established cell lines, and preparations obtained from patients with different leukemic disorders. The structure bearing the epitopes recognized by the two monoclonal antibodies was characterized immunologically (immunoprecipitation, SDS-PAGE analysis, immunomodulation, and competition with other antibodies) and by various functional assays. On the basis of inhibition tests, the AB8.28 molecule seems to be related functionally and/or structurally with the IgG Fc receptor. By contrast, the A10 structure does not share this activity and so far has eluded any precise biological characterization.

Antibodies, Monoclonal↗
PubMed1985

Theophylline induced non specific suppressor activity in human peripheral blood lymphocytes.

It is wellknown that theophylline yields phenotypic changes on suppressor cells. In the present study we investigated the possibility that theophylline could directly induce a suppressor activity on a lymphocyte subpopulation. We observed that a short preincubation (120 min at 37 degrees C) with theophylline (1mM) activates human peripheral blood lymphocytes to suppress mitogenic response of autologous cells. This activity was not evident on a T cell subpopulation depleted of theophylline-sensitive (T-sens) lymphocytes. Theophylline mediated suppressor activity is only present in the Concanavalin A stimulated cultures, thus suggesting a synergism between Concanavalin A and theophylline in the expression of non specific suppression. Moreover we observed that after a 24 hrs preincubation of lymphocytes in complete culture medium there was a complete loss of theophylline-induced suppression. Such a preincubation time also produced a decrease in the theophylline-mediated enhancement of intracellular 3', 5' cyclic adenosine monophosphate levels and the impairment of E-rosette formation, suggesting that theophylline acts mainly on a "short-lived" suppressor lymphocyte subset.

Adult↗
PubMed1985

Abnormal OKT4/OKT8 ratio and deranged capping in ataxia-telangiectasia.

Two sisters with ataxia-telangiectasia (A-T) and their parents were investigated for some parameters related to immunological functions. We found a decrease of total mature T lymphocytes, a decrease of OKT4+ helper-inducer T subset, and normal values of OKT8+ suppressor-cytotoxic T subset; a normal decrease of E rosette formation after incubation in vitro with theophylline, with a lowered E rosette capacity in one patient. The responses to phytohemagglutinin (PHA)and concanavalin A (ConA) were lowered. In addition we observed a reduction of basal capping of B lymphocytes in one patient and in her parents: this phenomenon could be related to cytoskeletal disorders, possibly involved in the pathogenesis of the disease.

Adolescent↗
PubMed1984

In vivo effects of a single infusion of theophylline on human peripheral blood lymphocytes.

It has recently been proposed that theophylline activates T suppressor systems in vivo and this evidence is further supported by the ability of the drug to attenuate the allograft rejection in humans and in experimental animals. In this study the acute effects of aminophylline on human peripheral blood lymphocyte (PBL) mitogenic responses have been investigated. PBL from healthy young volunteers who received intravenous aminophylline (5 mg/kg i.v. over 20 min) showed an increased proliferative response to phytohaemagglutinin. This was correlated with an augmented OKT4/OKT8 ratio, due to an absolute increase in the OKT4+ subset as well as a decrease in OKT8+ cells. Furthermore, following in vivo aminophylline we observed a significant rise in lymphocyte cAMP levels. These data, together with studies from other laboratories, suggest that the dosages and duration of treatment may influence greatly the theophylline-induced modulation of immune functions.

Adult↗
PubMed1984

Generation and characterization of murine monoclonal antibodies against HLA Class II molecules.

HLA Class II antigens (human la) are coded by Major Histocompatibility Complex and play important biological roles in health and disease. In this report we describe the generation and characterization of nine murine monoclonal antibodies (MoAbs) specific for determinants localized on the human la molecules. The reactivity of these MoAbs inferred from serological analysis along with the data obtained from biochemical characterization of the target structures allowed a classification of these reagents as monomorphic and polymorphic. Two monomorphic MoAbs, identifying different subsets of human la molecules, were studied in detail.

Animals↗
PubMed1983

A double-blind comparative study of the clinical efficacy of fluvoxamine and chlorimipramine.

1 We report the results of a comparative clinical trial of a new antidepressant drug fluvoxamine (a specific re-uptake inhibitor of 5-hydroxytryptamine (5-HT)) with chlorimipramine. Thirty-two patients with mixed depression received one or the other drug at the same daily dosage of 150 mg. 2 In both drug groups there was an overall clinically significant improvement for all items on the Hamilton Rating Scale for Depression (67% improvement in both groups). 3 In the chlorimipramine group there were more digestive symptoms and anticholinergic effects; the difference with the fluvoxamine group approached statistical significance. 4 No clinically important effects of either treatment were observed on heart-rate or blood pressure.

Adult↗
PubMed1981

[Fasting glycosylated hemoglobin A1c and behavior of blood sugar and blood insulin after oral glucose tolerance test in subjects with a family history of diabetes].

In a group of subjects with a known family history of diabetes (subjects with high risk of diabetes) and in two control groups, one of normal subjects and the other of poorly controlled insulin-dependent diabetic patients, all with normal blood levels of cholesterol and triglyceride, the fasting HbA1c concentration and the glycemic and insulin response to OGTT (1 g/kg of body weight) were studied. A prompt increase in serum insulin was observed both in normals and in subjects with a known family history of diabetes (poor in diabetics, of course), but insulin peak was significantly higher in the second ones. As in diabetes patients as in subjects with a known family history of diabetes, the HbA1c levels were significantly higher than in normal subjects, but significantly less high in subjects with a known family history of diabetes than in diabetics. These data might suggest that the prediabetic states generally joint with hyperinsulinemia and the HbA1c determination could contribute to the selection of those prediabetic states.

Adult↗
PubMed1981

[The response of pancreatic alpha and beta cells to oral glucose stimulation in subjects with risk of diabetes].

Oral glucose tolerance tests (g 1/kg body weight were performed in 14 high diabetic risk subjects (mean age: 39,5 years), 9 insulin-dependent diabetic patients (mean age: 37,8 years) and 14 normal subjects (mean age: 31,5 years). Glucose, IRI and IRG were determined at various intervals. In the high diabetic risk subjects: 1) the OGTT was normal; 2) the insulin response to carbohydrate ingestion was significantly higher than in normals and, of course, in diabetics; 3) the fasting glucagon levels showed no significant differences from the normals; 4) significant suppression of fasting glucagon concentration was observed in normals after oral glucose, but not in high diabetic risk subjects and in diabetic patients. On the basis of our findings it might be suggested, therefore, that in the subjects, who are genetically pre disposed to developing diabetes mellitus, insulin does not suppress pancreatic glucagon secretion or owing to a functional disorder among alpha- beta- and delta-cells, somatostatin secretion is deficient or slow with following hyperinsulinemia and hyperglucagonemia.

Adult↗
PubMed1980

[Exhaustibility of beta cells in the aged after repeated stimuli].

Seven aged subjects (mean age 78,5 years) and seven young controls (mean age 23,8 years), all nondiabetics and non-obese, were given intravenous injections of glucose, glucose and arginine, tolbutamide, tolbutamide and glucagon at 30 minutes intervals in order to determine the maximum insulin-secretory capacity of their pancreatic beta-islet cells after intensive stimulation. The response iun the elderly group was less prompt and quantitatively smaller at all stage of the test, but the beta-cells both in aged and in young subjects showed no evidence of exhaustion.

Adult↗
PubMed1980

Serum glucagon after arginine infusion in aged and young subjects.

In 12 aged nondiabetic subjects, 10 aged diabetic subjects, and 6 young nondiabetic subjects the glucose, insulin, glucagon and growth hormone responses to the intravenous administration of arginine were studied. A prompt increase in the levels of blood glucose, serum insulin and serum glucagon was observed, but the glucose and glucagon peaks were significantly higher in the aged nondiabetic and diabetic subjects. Growth hormone secretion did not differ between the nondiabetic aged and young subjects. These findings suggest the hypothesis that glucose intolerance in old age is due to increased release of glucagon.

Adult↗
PubMed1978

[Raised glucagon levels of the blood induced by arginine: relation to blood sugar, blood insulin and STH in aged non-diabetics and diabetics].

In a group of aged nondiabetic and diabetic subjects and in a group of young subjects the glycemic, insulin, growth hormone and glucagon response to intravenous arginine was studied. A prompt increase in blood glucose, serum insulin and glucagon levels was observed, but glucose and glucagon peaks were significantly higher in older non diabetic and diabetic subjects. Growth hormone secretion did not show any difference between aged nondiabetic and young subjects, on the contrary it is lower in diabetics. These findings might suggest the hypothesis of the glucose intolerance during old age due to increased release of glucagon.

Adult↗
PubMed1977

Inhibition of glycolysis and interference with protein synthesis in hepatoma cells.

Ascites hepatoma cells grown in Wistar rats were incubated anaerobically in the absence of glucose or in the presence of both glucose and D(+)glucosamine, or monoiodoacetate, or NADH, which interfered with glycolysis at different steps and with different mechanisms: Under all these conditions the incorporation of amino acids into the proteins of hepatoma cells was severely reduced without any clear relationship to the degree of inhibition of glycolysis. The postmitochondrial supernatants showed defective incorporation only when obtained from cells incubated in the absence of glucose or in the presence of monolodoacetate; inhibition of glycolysis by glucosamine and NADH did not seem to affect the subcellular basis for protein synthesis. When present, the defect of the cell sap (monoiodoacetate and absence of glucose) and to disaggregation and reduced functional capacity of the polysomes (absence of glucose). The results suggested that the effects of the inhibition of glycolysis on protein synthesis and on the integrity of the protein-synthesizing machinery--which were primarily due to the depletion of the energy stores--might have been modified by the particular mechanism of action of the inhibitor and by the way low levels of ATP were reached in the cell.

Adenosine Triphosphate↗