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Biomedical subjects

A Tedeschi

Publications and source records attributed to A Tedeschi.

At least 91 records · Page 5Linked to original sources

Inducing and enhancing effects of IL-3, -5, and -6 and GM-CSF on histamine release from human basophils.

The effects of interleukin (IL)-2, -3, -4, -5, -6, and -7 and granulocyte-macrophage colony-stimulating factor (GM-CSF) on histamine release from human basophils were evaluated. IL-3 was the only cytokine with histamine-releasing activity. This activity was observed predominantly on basophils from allergic patients (mean release +/- SEM, 33.9 +/- 9.5%; n = 12), whereas basophils from normal subjects responded less frequently to stimulation with IL-3 (mean release +/- SEM, 2.8 +/- 1.0%; n = 22). The effect of IL-3 was time and temperature dependent, since release was optimal after incubation for 120 min at 37 degrees C. When cell-bound IgE were eluted at acid pH, basophils became unresponsive to IL-3; however, IL-3-induced histamine release correlated with anti-IgE-induced histamine release in allergics, but not in normals. IL-3, IL-5, IL-6, and GM-CSF enhanced significantly anti-IgE- and FMLP-induced histamine release. In contrast, IL-2, IL-4, and IL-7 were devoid of any significant histamine-releasing or -potentiating activity. These results indicate that IL-3 can induce and IL-3, -5, and -6 and GM-CSF can enhance histamine release from human basophils, suggesting a possible role of these cytokines in the expression of allergic reactions.

Adult↗

PBSC collection after high dose chemotherapy followed by G-CSF in patients with malignancies: analysis of results regarding factors affecting the yield of hemopoietic progenitors.

High-dose non ablative chemotherapy followed by growth factors efficiently mobilizes and amplifies Peripheral Blood stem Cells (PBSC). Cytofluorimetric PBSC monitoring reduces the number of leukapheresis needed to collect sufficient amounts of progenitors to restore hemopoiesis after myeloablative therapy. Twenty-eight patients, affected by lymphoproliferative disorders, were primed with non myeloablative chemotherapy followed by G-CSF 5 micrograms/kg/die subcutaneously, until leukapheresis. A total number of 90 leukaphereses was performed (median: 3 per patient) using blood cell separator CS 3000 Plus Baxter; we collected 1 +/- 0.8 x 10(8)/kg mononuclear cells (MNC), 6 +/- 9 x 10(4)/kg CFU-GM and 4 +/- 5 x 10(6) CD34+ cells for each procedure. The statistical analysis showed that the number of progenitors collected was dependent on the age, number and type of previous chemotherapies and interval between the last chemotherapy and the priming; the type of priming, type and status of disease, sex, and bone marrow involvement were not significant. Duration of neutropenia after megachemotherapy was very short; in two cases platelet support was necessary and only two patients needed hospitalization. Our experience shows that high-dose non ablative chemotherapy followed by G-CSF is safe and yields large amounts of PBSC; several factors influence the quality of collections mainly regarding age and the previous treatment.

Adolescent↗

Enteral nutrition following total laryngectomy.

Body composition was measured in patients who underwent total laryngectomy for carcinoma and who were enterally fed throughout the postoperative period with full liquid artificial mixtures. The intestinal complications were very mild and required no changes in the nutritional program. Body sector sizes remained essentially unchanged until the end of the support, malnutrition did not occur and the postoperative local infection rate was very low. On the contrary, in patients fed with blenderized food, the amount of enteral infusion had to be reduced because of poor tolerance or abdominal discomfort; in this case caloric intake was largely inadequate. Fall in BW and BCM size and increase of TBNa/TBK ratio demonstrated a postoperative impairment of the nutritional status. Furthermore, the postoperative infection rate, the number of days with fever and the length of antibioticotherapy were higher than those observed in patients fed with full liquid mixtures.

Aged↗

Ionic regulation of human basophil releasability. I. Inhibitory effect of copper.

The effects of copper (CuSO4 and CuCl2) on in vitro histamine release from human basophils stimulated by anti-IgE and Ca2+ ionophore A23187 were evaluated. Both CuSO4 and CuCl2 caused a dose-related inhibition of histamine release, which was more pronounced on anti-IgE- than on Ca2+ ionophore-induced histamine release. The concentration which produced 50% inhibition of anti-IgE-induced histamine release was 1.3 microM for CuSO4 and 1.5 microM for CuCl2; the maximal inhibition of Ca2+ ionophore-induced histamine release was 33% for CuCl2 (4 microM) and 51% for CuSO4 (16 microM). The inhibitory effect on anti-IgE-induced histamine release persisted also when extracellular Cu2+ was removed by cell washing before stimulation, whereas no inhibition of Ca2+ ionophore-induced histamine release was found when extracellular Cu2+ was removed. The activity of Cu2+ was independent of any effects of deuterium oxide and colchicine, two agents known to interact with microtubules. Increased extracellular Ca2+ concentrations reduced the inhibitory effect of CuCl2 on Ca2+ ionophore-induced histamine release, and Schild plot analysis demonstrated that Cu2+ ions are competitive antagonists of Ca2+ ions. These results indicate that Cu2+ ions in the micromolar range down-regulate anti-IgE- and Ca2+ ionophore-induced histamine release. Since Cu2+ concentration in human plasma is in the micromolar range (30 microM with 10-30% of free Cu2+), it is conceivable that Cu2+ ions contribute to the in vivo regulation of histamine release from human basophils.

Adult↗

Mediator release in cerebrospinal fluid of human immunodeficiency virus-positive patients with central nervous system involvement.

In this study we evaluated the release of some mediators of inflammatory reactions such as histamine (H), leukotriene B4 (LTB4), leukotriene C4 (LTC4) and prostaglandin D2 (PGD2) in the cerebrospinal fluid (CSF) of 15 patients with acquired immunodeficiency syndrome (AIDS), eight with opportunistic infections of the central nervous system (CNS) and seven without HIV-related neurological pathology, and of 25 HIV-negative control subjects with other neurological diseases. The cerebrospinal LTB4 level was increased in all the AIDS patients (mean 348 pg/ml); the control group revealed normal levels of LTB4 in the CSF (mean 63.2 pg/ml). The PGD2 level in the HIV-positive (mean 264 pg/ml) patients was higher than of the control subjects (mean 50 pg/ml), while low LTC4 levels were found both in the HIV-positive and control groups. We did not find any significant concentration of H in the CSF of either the HIV-positive or the control subjects. These findings may be due to the presence of chronic HIV infection or to the opportunistic infections of the CNS that so often occur in the latest stages of the disease.

Brain Diseases↗

Desferal (desferrioxamine)--a novel activator of connective tissue-type mast cells.

The effect of Desferal (desferrioxamine), an iron-chelating agent with allergic side effects, was examined on human basophils and rodent mast cells (MCs) in vitro and in the human skin. Even at a high concentration (100 mg/ml), the drug neither induced histamine release (HR) from human basophils nor primed these cells to release higher amounts of histamine when they were activated with f-met-peptide or anti-IgE antibodies. In contrast, in all seven subjects studied, intradermal injection of Desferal (0.1 mg/ml to 100 mg/ml) elicited classic wheal-and-flare responses. Ingestion of 10 mg of cetirizine, an H1 antagonist, 3 hours before the intracutaneous administration of Desferal, significantly reduced the diameters of both wheal-and-flare reactions, indicating that the drug caused local HR. Desferal also induced HR from rat peritoneal MCs in vitro but had no effect on mouse bone marrow-derived MCs. These results suggest that Desferal has a direct, IgE-independent, stimulatory effect on connective tissue-type MCs. Thus, it may be used as a positive control in skin testing.

Animals↗

Regulation of histamine release from human basophil leucocytes: role of H1, H2 and H3 receptors.

A novel class of histamine receptors (H3), controlling histamine synthesis and release, was described in rat and human brain and peripheral nerve endings. The present study was undertaken to evaluate whether H3 receptors contribute to the regulation of histamine release from human basophils. Basophil leucocytes were incubated with a H3 antagonist (thioperamide; concentrations ranging from 1 nM to 10 microM) or with a H3 ((R)alpha methyl-histamine; concentrations ranging from 1 to 100 mM), and subsequently were stimulated with optimal doses of anti-IgE and formyl-methionyl-leucyl-phenyl-alanine (f-met peptide). No significant modifications of histamine release were observed after incubation either with the H3 agonist or with the H3 antagonist. By contrast, a H2 antagonist (cimetidine; concentrations ranging from 1 to 100 microM) exerted a dose-dependent enhancing effect on anti-IgE- and, to a lesser extent, on f-met peptide-induced histamine release. A H1 antihistamine (chlorpheniramine; concentrations ranging from 100 nM to 1 microM), at the highest concentration employed, displayed an inhibitory activity on IgE-dependent and IgE-independent histamine release. Exogenous histamine was shown to exert a dose-dependent inhibitory effect on two-staged anti-IgE-induced histamine release. Taken as a whole, these results suggest that H3 receptors are not involved in the regulation of histamine release from human basophils; by contrast, H2 receptors participate in controlling histamine release from human basophils, as previously demonstrated by other authors.

Adult↗

Study of the effects of paf-acether on human nasal airways.

In 6 normal subjects and 6 patients with allergic rhinitis, nasal response to insufflation of paf-acether (paf, platelet-activating factor), lyso-paf and histamine was evaluated. Nasal challenge with paf, at doses of 300 and 600 nM, induced nasal obstruction, associated with an increase in nasal airway resistances, measured by anterior passive rhinomanometry. Maximum increase in nasal airway resistance was observed at 30 min after challenge (mean percent change + 481 with 600 nM paf; P less than 0.05). Other symptoms induced by paf insufflation were rhinorrhea (6 out of 12 subjects), itching (8 out of 12), sneezing (4 out of 12) and a burning sensation (6 out of 12). No differences were observed between normal and rhinitic subjects, concerning nasal sensitivity to paf. Neither nasal symptoms nor changes in nasal airway resistance were observed after nasal challenge with lyso-paf (300 and 600 nM); by contrast, histamine (100 nM) induced sneezing, nasal obstruction, itching and rhinorrhea in all the studied subjects, associated with an increase in nasal airway resistance (maximum 5 min after challenge; percent change + 358; P less than 0.02). Nasal effects of paf were not mediated by histamine, since no increase in histamine levels was observed in nasal washings following paf insufflation. We conclude that paf may have pathogenetic relevance in allergic rhinitis.

Adolescent↗

Low MW B-cell growth factor potentiates histamine release from human basophil leucocytes.

The aim of the present study was to evaluate the effects of a commercial preparation of low molecular weight (MW) B-cell growth factor (BCGF), a product of activated human T cells, on histamine release from stimulated human basophils. In all the 23 cases tested, BCGF enhanced significantly the histamine release from stimulated human basophil leucocytes. After leucocyte incubation with 1% v/v BCGF, anti-IgE-induced histamine release increased from 11.9 +/- 1.9% to 31.8 +/- 3.3% (mean +/- SEM; P less than 0.001), formyl-methionine peptide-induced histamine release increased from 24.9 +/- 3.9% to 50.3 +/- 5.3% (P less than 0.001) and complement-mediated (i.e. induced by zymosan-activated human serum) histamine release increased from 10.7 +/- 1.8% to 29.2 +/- 5.2% (P less than 0.001). The enhancing effect of BCGF on histamine release was related to dose, temperature and time, since it was optimal after incubation with 10% v/v BCGF at 37 degrees for 60 min. BCGF activity persisted when the cells were washed after incubation and could also be observed when leucocyte incubation was carried out in the absence of extracellular Ca2+. It is noteworthy that basophils which showed a low response to activating agents released significant amounts of histamine after incubation with BCGF. These observations support the hypothesis that lymphocytes and lymphocyte-derived products may play a role in triggering and maintaining allergic reactions.

Adult↗

Enhanced basophil releasability in subjects infected with human immunodeficiency virus.

Spontaneous histamine release and basophil response to IgE-dependent (anti-IgE) and IgE-independent (formyl-methionine peptide, calcium ionophore A23187) stimuli were evaluated in 15 patients with acquired immunodeficiency syndrome (AIDS), 8 with AIDS related complex (ARC), 7 with lymphadenopathy syndrome (LAS), 11 seropositive asymptomatic subjects, 10 human immunodeficiency virus (HIV)-seronegative drug addicts, and 20 normal subjects. Both spontaneous histamine release and anti-IgE-induced histamine release were significantly increased in HIV-infected subjects, in comparison with seronegative drug addicts and normal controls. Basophil response to anti-IgE was higher in AIDS/ARC patients than in seropositive asymptomatic subjects and LAS patients, although the difference was not statistically significant. When basophils were challenged with 0.1 microM formyl-methionine peptide, a significantly increased histamine secretion was found in HIV-infected subjects; conversely, at the higher formyl-methionine peptide concentration (10 microM), as well as at all calcium ionophore A23187 concentrations, histamine release was similar in all the studied groups. No correlation was found among anti-IgE-induced histamine release, total lymphocyte counts, CD4+ and CD8+ T cell counts, and total serum IgE levels. These findings indicate that infection with HIV is associated with an increased basophil releasability. This could be of some relevance in the increased incidence of allergic manifestations and adverse drug reactions observed in AIDS patients.

AIDS-Related Complex↗

Mediator release after endobronchial antigen challenge in patients with respiratory allergy.

The aim of the present study was to evaluate the release of some potential mediators of allergic reactions, such as histamine, peptide leukotrienes (LTs), LTB4 and prostaglandin D2 (PGD2), in bronchoalveolar lavage (BAL) fluids from 11 patients with respiratory allergy (eight with bronchial asthma and three with allergic rhinitis), who underwent specific endobronchial challenge. Histamine, peptide LT, and PGD2 levels in BAL fluids increased significantly after antigen stimulation both in patients with asthma and in patients with rhinitis. By contrast, LTB4 concentration was always below the limits of detection of the radioimmunoassay. In patients with asthma, histamine concentration increased from 5.3 +/- 0.6 ng/ml in lavages obtained before provocation to 20.2 +/- 5.8 ng/ml (mean +/- SEM; p less than 0.04) 5 minutes after bronchoprovocation. Peptide LTs increased from 0.32 +/- 0.08 to 0.82 +/- 0.21 ng/ml (p less than 0.02) and PGD2 from 0.06 +/- 0.01 ng/ml to 0.36 +/- 0.09 ng/ml (p less than 0.02). Elevated histamine, peptide LT, and PGD2 concentrations were also found in the 15-minute postchallenge BAL fluids. Similar results were obtained in patients with rhinitis. Histamine concentration was 3.4 +/- 0.6 ng/ml in prechallenge bronchial lavages and 11.3 +/- 1.7 ng/ml in postchallenge lavages; peptide LTs increased from 0.13 +/- 0.008 ng/ml to 0.73 +/- 0.21 ng/ml, and PGD2 from 0.05 +/- 0.01 ng/ml to 0.26 +/- 0.06 ng/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Differential effect of hypertonicity on FMLP-, anti-IgE- and Ca2+ ionophore A23187-induced histamine release from human basophil leukocytes.

Effects of different extracellular Na+ and K+ concentrations (respectively, 135, 155, 220, 260 mM NaCl, and 2.7, 20, 50, 100 mM KCl) on IgE-dependent and IgE-independent histamine release from human basophils were examined. High extracellular Na+ and K+ concentrations were shown to reduce N-formyl-methionyl-leucyl-phenyl-alanine- (FMLP), but not anti-IgE- or Ca2+ ionophore A23187-induced histamine release. A high extracellular Ca2+ (7.2 mM CaCl2) concentration increased basophil response to anti-IgE and FMLP. The enhancement of FMLP- but not of anti-IgE-induced histamine release was antagonized by high extracellular Na+ and K+ concentrations. When leukocytes were suspended in isotonic choline chloride solutions (choline is a nonpermeant monovalent cation), an enhancement of anti-IgE- and FMLP-induced histamine release was observed. This suggests that monovalent cations, namely Na+ ions, at physiological concentrations, downregulate histamine release from human basophils. At high choline chloride concentrations, FMLP-, but not anti-IgE-induced histamine release was inhibited. Thus, the reduction of FMLP-evoked histamine secretion from human basophils seems to be due to hypertonicity and not to the type of monovalent cation, either permeant or nonpermeant, contained in extracellular milieu. The different effects of a hypertonic solution on anti-IgE and FMLP-induced histamine release are probably related to the different cell activation pathways triggered by the two stimuli.

Adolescent↗

Ranitidine in children with peptic ulcer and patients with pancreatic cystic fibrosis.

This article describes experience of the use of ranitidine in children with peptic ulcer and patients with pancreatic cystic fibrosis. Ranitidine proved to be efficacious and well tolerated, the percentage of healing being 89.4%. Ranitidine was also used in subjects with gastritis from Campylobacter pylori, obtaining rapid regression of subjective symptoms. Administration of ranitidine to cystic fibrosis patients improved the efficacy of the pancreatic extract, with consequent enhancement of digestive compensation.

Administration, Oral↗

Helicobacter pylori infection: a simplified diagnostic approach.

We evaluated the diagnostic accuracy of endoscopic finding of nodular antritis and rapid urease test (RUT) in order to simplify the approach to the diagnosis of Helicobacter pylori (H. pylori) infection. Forty-four consecutive patients (mean age 7.9 yr, range 6-13 yr) referred because of recurrent abdominal pain as the main symptom, were prospectively investigated for the presence of H. pylori. H. pylori positivity or negativity was defined as the concordance of two of the following tests: RUT, microbiologic culture, and histologic examination on bioptic samples. RUT sensitivity was 100%, whereas specificity was 87.5%. The presence of nodular antritis had a sensitivity of 96.4% and specificity of 87.5% in H. pylori infection diagnosis. The predictivity value of combined RUT and nodular antritis, whether positive or negative, was 100%. Only in case of discordance do we suggest the utilization of other expensive tools for diagnosis of H. pylori infection.

Abdominal Pain↗

[Evaluation of the efficacy of the magnesium salt of N-acetyl-aspartyl-glutamic acid in the treatment of acute rhinitis].

The object of the above study was to evaluate the tolerability and possible therapeutic use of MgNAAGA (Mg salt of N-acetyl-aspartyl-glutamic acid) in patients with allergic rhinitis. Out of 22 subjects with respiratory allergy, 12 were treated for 15 days with MgNAAGA and 10 with DSCG for the same length of time. During this period, patients kept a diary in which they recorded the following symptoms: rhinorrhea, itching, sneezing and nasal obstruction. The trial drug was found to be well tolerated and not to give rise to relevant side effects. The therapeutic efficacy was similar to that of DSCG.

Administration, Intranasal↗