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Biomedical subjects

G Ferrari

Publications and source records attributed to G Ferrari.

At least 127 records · Page 7Linked to original sources
PubMed1993

[New diagnostic and therapeutic prospects in peripheral nodules of the lung: surgical video thoracoscopy].

The new findings and results of laparoscopic surgery lead us to apply this technique in thoracic surgery. Thoracoscopy is an old diagnostic procedure, but advanced imaging techniques, improved optics and new classes of instrument have paved the way for many diagnostic and therapeutic approaches, before not feasible. Now it is possible to treat spontaneous pneumothorax, removal of mediastinal and peripheral tumors, with minimally invasive surgery. It is our belief that thoracoscopic surgery will be a valuable tool in the near future for a variety of chest disorders.

Anesthesia, General↗
PubMed1993

Phenotype and function of stromal cells cloned from the ileal Peyer's patch of sheep.

The ileal Peyer's patch (PP) is the major site of B cell production and immunoglobulin diversification in lambs, but the factors which regulate these processes are poorly understood. As a first step toward identifying possible regulatory mechanisms, stable long-term cultures of ileal PP stromal cells were established at the clonal level. Four distinct cell types were identified by their phenotype and growth requirements. Immunohistochemical staining confirmed that all clones were mesenchymal (vimentin+; cytokeratin-) in origin and were negative for T cell, B cell, and macrophage markers. Three cell lines were negative for major histocompatibility complex (MHC) I and II molecules, but one cell line, SCN, expressed MHC I, MHC II and CD44 molecules, and a subpopulation of SCN cells expressed BAQ44A, a B cell differentiation molecule. The four cell lines produced different types and amounts of extracellular matrix proteins, and their growth was not influenced by exogenous human interleukin 1 (IL-1), IL-2, transforming growth factor beta 1 (TGF beta 1), or bovine fibroblast growth factor (FGF) but was influenced by serum. When tested for their capacity to support lymphocyte growth, all clones produced a soluble factor(s) that was mitogenic for ileal and jejunal PP cells and thymocytes. Similar growth promoting activity was observed with culture supernatants of murine, human and bovine fibroblasts but could not be reproduced using recombinant human cytokines. Furthermore, coculture of stromal cells with ileal PP follicular B cells elicited a proliferative response unique to each stromal cell line. Coculture with increasing numbers of SCN cells inhibited B cell proliferative responses, whereas coculture with SCG2 and SCF32 cells enhanced B cell proliferative response at both low and high stromal cell densities. Ileal PP follicular B cells rapidly bound to the surface of all stromal cell clones, and this interaction was specific when compared with thymocytes or peripheral blood lymphocytes. These results suggest that ileal PP stromal cells are a phenotypically and functionally heterogeneous population that may enhance or inhibit B lymphopoiesis in the ileal PP.

Animals↗
PubMed1993

Simultaneous infection with three different S. enteritidis strains in a nursing home resident.

A culture taken from a nursing home resident as part of a S. enteritidis outbreak was found to have a mixed infection due to three different strains of S. enteritidis. One of the three strains belonged to phage type (PT) 4, one to PT6 and one reacted with phages but did not conform to any typing scheme (RDNC). All three strains had the 38.9 megadaltons (MDa) plasmid found in the isolates from the outbreak-related cases, in addition the PT6 and RDNC strains harboured a 69.9 MDa plasmid. The importance of phage typing and plasmid analysis for S. enteritidis strain characterization and their epidemiologic and bacterial significance are discussed.

Aged↗
PubMed1993

Riboflavin uptake by rat small intestinal brush border membrane vesicles: a dual mechanism involving specific membrane binding.

The first step of riboflavin absorption was studied by determining the uptake of the vitamin by rat small intestinal brush border membrane vesicles. Vesicles were incubated at 25 degrees C in the presence of [3H]-riboflavin at concentrations within the physiological intraluminal range for rat. The time course of [3H]-riboflavin uptake was unaffected by Na+ or K+ gradients. The 5 sec uptake rate plotted as a function of the initial concentration of [3H]-riboflavin in the medium (0.125 to 7.5 microM) revealed the presence of a dual mechanism, with a saturable component (apparent kinetic constants: 0.12 microM for Km and 0.36 pmol.mg-1 protein x 5 sec-1 for Jmax) prevailing at low concentrations (< 2 microM), and a nonsaturable component prevailing at higher concentrations. The presence of a carrier-mediated system for riboflavin was validated by countertransport experiments. At equilibrium, uptake was almost completely accounted for by membrane binding, whereas at earlier times the transport component accounted for about 30% of total uptake. The plot of [3H]-riboflavin binding at equilibrium as a function of its concentration in the medium was quite similar to that of the 5 sec uptake rate in both intact and osmotically shocked vesicles and demonstrated the occurrence of a saturable component: binding constants were 0.07 (Kd in microM), 0.54 (Bmax in pmol.mg-1 protein), and 0.11 (Kd), 1.13 (Bmax), respectively, indicating the existence of specific riboflavin binding sites. The specificity of riboflavin binding to the membrane was confirmed by preliminary studies with structural analogues. Specific binding could represent the first step of a specific riboflavin entry mechanism in enterocytes.

Animals↗
PubMed1993

Egg-related Salmonella enteritidis, Italy, 1991.

In recent years, Salmonella enteritidis has become an increasingly important public health problem in Italy. In some parts of the country, the fraction of total human salmonella isolates accounted for by S. enteritidis has risen from 3-4% in the mid-1980s to more than 30% in 1990. Between 1990 and 1991, the number of reported S. enteritidis outbreaks increased more than sixfold. The 33 outbreaks reported in 1991 occurred in seven contiguous regions in northern and central Italy and were clustered in time between June and October: in the majority, products containing raw or undercooked shell eggs were implicated. Five of the egg-related outbreaks that occurred within a 30 kilometre radius over a 7-week period were investigated in detail. A phage type 1 strain containing a 38.9 MDa plasmid appeared responsible for three of the outbreaks, while in the remaining two a phage type 4 strain, also with a 38.9 MDa plasmid was isolated. Efforts are being made to enhance epidemiological surveillance and laboratory evaluation, and the use of pasteurized eggs has been recommended for high-risk populations.

Disease Outbreaks↗
PubMed1993

The impact of HIV-1 infection on phenotypic and functional parameters of cellular immunity in chimpanzees.

As a means of assessing the immunological impact of HIV infection in the chimpanzee, as well as the participation of the cellular components in the control of HIV infection in these animals, various aspects of cellular immunity were investigated in chronically HIV-infected chimpanzees. Eight HIV-1-infected chimpanzees were included in this study; two of them were infected for more than 5 years and six for nearly 3 years at the time of study. All of the chimpanzees received either 40 or 100 TCID50 of HTLV-IIIB. Circulating peripheral blood lymphocytes were studied by flow cytofluorimetric analysis in order to reveal possible alterations in the CD4:CD8 ratio, as well as in specific CD4+ and CD8+ cell subpopulations. Chronically infected chimpanzees did not present significant alterations in the percentage of CD4+ or CD8+ lymphocyte subsets. Interestingly, the CD8+/CD57+ cell subset was not detectable. The expression of markers for activation on circulating lymphocytes, usually higher in the HIV-infected patients, was not altered in infected animals. The functional aspects of specific anti-HIV-1 non-MHC and MHC-restricted cellular cytotoxic reactivities were also investigated. The results were compared with the findings in normal uninfected chimpanzees and in HIV-infected humans. Only one chimpanzee (881) developed a detectable, specific non-MHC-restricted anti-HIV-1- reactivity. Compared to that seen in humans, the ontogeny of this activity is delayed. Among the other infected chimpanzees, no specific anti-HIV cellular reactivities were detectable in the peripheral blood. In chimpanzees, HIV-1 infection evidently does not elicit the same strong cellular reactivity as that detected in infected patients. The absence of chronic cellular activation, despite continued viral replication, may highlight a key determinant in HIV-1-induced pathogenesis that is likewise absent in infected chimpanzees.

Animals↗
PubMed1993

Transfer of the ADA gene into bone marrow cells and peripheral blood lymphocytes for the treatment of patients affected by ADA-deficient SCID.

Severe combined immunodeficiency (SCID) caused by deficiency of the enzyme adenosine deaminase (ADA) is the first genetic disorder considered for human somatic cell gene therapy. ADA-SCID patients can be cured by HLA-matched sibling donor bone marrow transplantation. Alternative transplantation strategies as well as enzyme replacement are being tested in those patients who do not have a suitable matched sibling donor. Some ADA-SCID patients may not be candidates for cytoablation due to infectious damage to the lung or liver, or may have a milder phenotype that does not justify the risks associated with haploidentical bone marrow transplantation. Replacement therapy with PEG-ADA has resulted in improvement in growth, a variable increase in the number of peripheral blood lymphocytes, and a decrease in the incidence of severe infections. Another approach to the treatment of severe genetic diseases is now represented by somatic cell gene therapy. We and others have conducted experiments in vitro and in vivo that have documented that T-lymphocytes are suitable vehicles for gene transfer. Although the pluripotent stem cell remains the ideal target cell for somatic cell gene therapy of disorders of the hematopoietic system, the use of T-lymphocytes as gene therapy vehicles is specifically indicated for ADA-deficient patients where they represent the affected cells. Furthermore, the selective engraftment of T-cells only, following bone marrow transplantation, has resulted in reconstitution of cellular and humoral immunity. A model for the functional analysis in vivo of the human immune system has been utilized for the preclinical evaluation of this approach.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Deaminase↗
PubMed1993

Retroviral vector-mediated gene transfer into human primary myogenic cells leads to expression in muscle fibers in vivo.

Primary human myogenic cells isolated from fetal and adult muscle were infected with a high-titer, Moloney murine leukemia virus (MoMLV)-derived retroviral vector expressing a bacterial beta-galactosidase (beta-gal) gene under long terminal repeat (LTR) control. Gene transfer efficiency averaged 50% in both fetal myoblasts and adult satellite cells, as revealed by beta-gal staining. The reporter gene was stably integrated, faithfully inherited, and expressed at significant levels in myogenic cells for at least 10 generations under clonal growth conditions, and throughout the culture life span upon differentiation into myotubes. Comparable gene transfer efficiency was obtained in myogenic cells from muscle biopsies of patients affected by a number of genetic or acquired myopathies, including Duchenne muscular dystrophy. Transduced normal human satellite cells were injected into regenerating muscle of immunodeficient mice, where they formed new muscle fibers in which the product of the reporter gene was detectable for 2 months after injection. These results show that retroviral vectors can be used to transfer foreign genes with high efficiency into normal or abnormal primary human myogenic cells, leading to stable expression into mature muscle. Satellite cells engineered in this way might represent an effective tool for gene therapy of muscular dystrophies as well as for systemic delivery of recombinant gene products for correction of inherited and acquired disorders. The human-mouse model described here will allow in vivo testing of such gene therapy approaches.

Adolescent↗
PubMed1993

Double-blind study of the efficacy and safety of sertraline versus fluoxetine in major depression.

An eight-week double-blind, multicentre study was performed to evaluate the efficacy and safety of sertraline vs. fluoxetine in the treatment of major depression (DSM-III-R). There were 108 out-patients, from nine Italian centres, entered into the study, of whom 88 were evaluable (48 sertraline, 40 fluoxetine). The final mean daily dose of sertraline was 72 mg and for fluoxetine it was 28 mg. Both treatment groups showed a statistically significant improvement from baseline at one week, and this was maintained until the end of treatment for all of the following measures: Hamilton Rating Scales for Depression and Anxiety, the Montgomery Asberg Depression Rating Scale, Clinical Global Impressions Scale, Zung Self-Rating Scale for Anxiety and the Leeds Sleep Evaluation Questionnaire. Although there was a numerical advantage for sertraline on several efficacy measures, there was no statistically significant difference found between the treatment groups. The incidence of adverse events was similar for both treatments; 40.4% for sertraline and 39.3% for fluoxetine. However, adverse events were generally rated by patients as of lower severity in the sertraline group. In addition, for the fluoxetine group, there was a higher incidence of agitation, anxiety and insomnia than for sertraline. Sertraline was considered to be better tolerated than fluoxetine overall, since only 9.6% of sertraline-treated patients discontinued treatment due to therapy failure whereas in the fluoxetine-treated group this figure was 19.6%. By contrast, 13.5% of sertraline-treated patients discontinued prematurely because of clinical improvement, compared with 10.7% of fluoxetine-treated patients.

1-Naphthylamine↗
PubMed1993

[Neuroleptic-induced dysphoric response in non-schizophrenic patients].

In 50 psychiatric inpatients treated with neuroleptics we observed neuroleptic-induced dysphoria in 4% and neuroleptic-induced akathisia in 18% of the cases. In our sample there was no schizophrenics among dysphoric responders. We discuss the implication of the findings and the relationship between dysphoric response and subjective phenomena of akathisia.

Adult↗
PubMed1993

[The immediate and long-term efficacy of electrical cardioversion in atrial fibrillation].

With the aim to identify short- and long-term features predictive of successful electric cardioversion in stable atrial fibrillation, 186 consecutive patients submitted to electric cardioversion were reviewed. The following parameters were considered: age, atrial fibrillation duration, previous atrial fibrillation episodes, echocardiographic left atrial diameter, pre-treatment and prophylaxis with amiodarone. The patients were divided in 3 groups: Group I included 97 patients with mitral valve disease or mitral prosthesis, Group II included 27 patients with lone atrial fibrillation and Group III included 62 patients with different heart and extracardiac diseases. The electric cardioversion restored sinus rhythm in 155 patients (83%). The failure of the electric cardioversion was related only to a longer atrial fibrillation duration and to pre-treatment with amiodarone. Moreover, the failure of the electric cardioversion was more frequent in Group II patients (with lone atrial fibrillation) than in Group I patients (mitral disease or prosthesis; p < 0.005). Only for Group I patients failure of the cardioversion was related to a larger left atrium diameter (p < 0.05). Eighty-nine (57%) of the 155 patients converted to sinus rhythm were followed for at least 1 year. At 1 year sinus rhythm persisted in 57 patients (64%), and prophylaxis with amiodarone was the only predictor of sinus rhythm persistence (p < 0.05). Out of 68 patients with a 3 year follow-up, 29% still showed sinus rhythm after a single cardioversion and 37% after 2 or more cardioversions; after 5 years, out of 58 patients, those showing sinus rhythm were 6 (10.3%) and 9 (16%) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Analysis of the factors influencing bicarbonate balance during acetate-free biofiltration.

In acetate-free biofiltration (AFB), the physical separation between the base losses and the gains could facilitate the modeling of intradialytic bicarbonate (HCO3) balance. In order to verify this hypothesis, we analyzed in a multicenter study, 126 AFB sessions in which differing parameters were evaluated (dialysis time, blood flow, ultrafiltration, infused HCO3, pre- and post-dialytic HCO3, hematocrit and body wt). Statistical analysis performed with multiple linear regression showed that the post-dialysis HCO3 was significantly dependent (F = 21.68, d.f. 5.95, P < 0.001) directly on the amount of infused HCO3, the level of pre-dialysis HCO3 and the final body weight, and inversely on the dialysis time and the blood flow. HCO3 values predicted by the statistical model correlated well with the observed ones (r = 0.788, P < 0.0001) with a mean absolute difference of 2.138 mEq/liter. This modeling approach allowed us to predict, with a computer-aided procedure, the quantities of HCO3 to be infused to obtain a desired and personalized acidosis correction.

Acetates↗
PubMed1993

[Pulmonary toxicity due to amiodarone].

Two patients with coronary heart disease and previous myocardial infarction, treated with amiodarone for severe ventricular arrhythmias, developed pulmonary toxicity. The first developed pulmonary complications after 1 year of therapy at the maintenance dose of 300 mg/day, and the second after 4 months at 200 mg/day and 3 weeks at 400 mg/day. In the first patient, whose chest X-ray mainly showed interstitial infiltrates which resolved within more than 2 months after drug withdrawal, steroid therapy was administered. In the second patient, whose chest X-ray showed a pattern of pulmonary edema, the symptoms and signs resolved more rapidly after drug withdrawal and without steroid therapy. We suggest 2 distinct types of pulmonary toxicity in our patients. After withdrawal of amiodarone in the second patient the management of refractory ventricular arrhythmias was troublesome.

Aged↗
PubMed1993

Gangliosides rescue neuronal cells from death after trophic factor deprivation.

Serum-free cultures of PC 12 cells have been used as a model system for studying neuronal death occurring after neurotrophic factor deprivation. In this system, NGF rescues cells from death and prevents apoptotic DNA fragmentation. We report here that GM1 also promotes long-term survival of naive and NGF-pretreated PC 12 cells in serum-free medium and prevents internucleosomal cleavage of PC 12 cell DNA. In contrast to NGF, GM1 does not promote neurite outgrowth or somatic hypertrophy. The survival effects of GM1 are concentration dependent, with maximal activity at 30-50 microM. Optimal promotion of survival is obtained with multiple additions of GM1. Asialo-GM1 and sialic acid do not mimic these actions, indicating a requirement for the intact GM1 molecule. Prevention of serum-free PC 12 cell death is also obtained with di-, tri-, and tetrasialogangliosides. The ganglioside effects on survival and DNA fragmentation appear to be independent of macromolecular synthesis. GM1 is also effective under conditions in which cellular protein kinase C activity is downregulated by preexposure to high concentration of 12-O-tetradecanoylphorbol-13-acetate. Furthermore, GM1 promotes long-term survival of cultured rat sympathetic neurons after withdrawal of NGF. These findings complement prior observations that gangliosides protect cerebellar granule neurons from neurotoxicity caused by exposure to excitatory amino acids and extend the actions of gangliosides to rescue of neuronal cells deprived of neurotrophic factor support.

Animals↗
PubMed1992

Transfer of the ADA gene into human ADA-deficient T lymphocytes reconstitutes specific immune functions.

Peripheral blood lymphocytes obtained from a patient affected by adenosine deaminase (ADA) deficiency and severe combined immunodeficiency were infected with a retroviral vector containing two copies of a human ADA minigene, and injected into bg/nu/xid (BNX) immunodeficient mice. Six to 10 weeks after injection, human T cells were cloned from the spleens of recipient animals and analyzed for proliferative potential, T-cell surface markers, expression of ADA activity, integration of retroviral sequences, T-cell receptor (TCR) beta gene rearrangement, and specificity of antigen recognition. Efficient gene transfer and expression restored proliferative potential in vitro and long-term survival in vivo. All clonable human T lymphocytes obtained from the spleen of recipient animals had high levels of vector-derived ADA enzyme activity and showed predominantly the CD4+ phenotype. Retroviral integrations and TCR-beta gene rearrangements demonstrated the presence of a variety of different clones in the spleens of recipient mice. Furthermore, the combined analyses of vector integration and TCR rearrangement provided evidence that a circulating progenitor cell was transduced by the retroviral vector, giving rise to different and functional TCRs. Evaluation of antigen-specificity demonstrated both alloreactive and foreign antigen specific immune responses. These results suggest that restoration of enzyme activity in human ADA-deficient peripheral blood T cells by retroviral-mediated ADA gene transfer allows in vivo survival and reconstitution of specific immune functions. Therefore, retroviral vector-mediated gene transfer into circulating mononuclear cells could be successful not only in maintaining the metabolic homeostasis, but also for the development of a functional immune repertoire. This is a fundamental prerequisite for the usage of genetically engineered peripheral blood lymphocytes for somatic cell gene therapy of ADA deficiency.

Adenosine Deaminase↗
PubMed1992

Age-related thiamin transport by small intestinal microvillous vesicles of rat.

The effect of aging on the intestinal transport of thiamin was studied using small intestinal microvillous vesicles prepared from groups of rats aged 1, 2, 6, 12 and 24 months, respectively. The vesicles (enrichment 14.6-17.8-fold) were incubated with 0.125 to 12.5 microM tritiated thiamin and the radioactivity taken up was measured radiometrically after rapid filtration. The time course and cumulative uptake curves of thiamin and the inhibiting potency of the thiamin structural analogs pyrithiamin, amprolium and oxythiamin on the saturable component of thiamin transport were determined. The vesicle diameter was measured by using a computerized morphometric procedure, and found to be decreased in aged rats. The Km and Jmax values of the saturable component of transport increased with increasing age, the difference with younger groups being statistically significant at 24 and 12 months. The inhibitory potencies of pyrithiamin and amprolium gradually decreased with increasing age, while oxythiamin was devoid of significant inhibitory activity. Passive permeability coefficients decreased with increasing age, reaching their lowest value at 24 months. These results show that aging is associated with intrinsic alterations of the enterocytic plasma membrane resulting in a decrease of the affinity for thiamin, associated with a faster rate of the saturable component of thiamin transport, and with a significant depression of the non-saturable component.

Aging↗