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P Pisati

Publications and source records attributed to P Pisati.

11 recordsLinked to original sources
PubMed1998

Dialysis hypersensitivity: a fading problem?

Allergic-type reactions experienced by patients on chronic hemodialysis are frequently reported in the literature, often related to compounds released during the hemodialysis sessions, in particular ethylene oxide (ETO). In these studies, dialysis patients seem to have higher values of IgE than those observed in a reference population. The aim of our work was to investigate IgE-related parameters of 126 dialysis patients in comparison with two control groups composed of healthy subjects and predialysis patients. IgE values were not significantly different in nonallergic dialysis patients, with a geometric mean (X) of 27.5 kU/l, when compared to healthy controls (X = 38 kU/l) and predialysis subjects (X = 40.7 kU/l). Higher values of IgE (X = 74.1 kU/l) were detected in allergic dialysis patients. However, only 3 patients, all without detectable antibodies against ETO, complained of anaphylactic symptoms during dialysis sessions in a 4-year surveillance period. At variance, 6 symptom-free patients carried IgE antibodies against ETO (range 0.7-15 kU/l), usually with high total IgE. Our results suggest a reduced frequency of hypersensitivity reactions during dialysis sessions. Furthermore, uremia does not alter IgE reactivity in the predialysis period or after long-term maintenance dialysis treatment.

Adult↗
PubMed1997

Induced sputum to assess airway inflammation: a study of reproducibility.

BACKGROUND: Infiltration of the airways mucosa with activated inflammatory cells appears to be a major factor in the pathogenesis of asthma and other airway diseases. Examination of sputum provides a direct method to investigate airway inflammation non-invasively. OBJECTIVES: The aim of the present study was to evaluate the reproducibility of cell counts on cytospins and fluid phase (eosinophil cationic protein, ECP) measurements in a selected portion of induced sputum. We aimed to confirm the validity of the tecnique by comparing measurements between stable asthmatics, allergic rhinithis and healthy subjects. METHODS: Sputum was induced with hypertonic saline (4.5%) twice within one week in 53 stable asthmatics, 16 subjects with seasonal rhinitis (out of the pollen season), and 19 healthy subjects. Reproducibility was examined within sample (two different plugs of the same sample) between sample (two specimens of induced sputum obtained within one week) and between examiners on stable subjects taking into account sample size, number of examinations per patients and Confidence Interval (CI) of the estimates. RESULTS: We have found that the method is highly reproducible within sample and between examiners for all types of cells and fluid phase measurements of ECP. It is reproducible between sample for eosinophils, macrophages, neutrophils and ECP, but not for lymphocytes and weakly for epithelial cells. Sputum from asthmatics, in comparison with the sputum of healthy subjects and subjects with rhinitis had higher eosinophils (asthmatics: 12.2% +/- 12.9, rhinitis: 0.4 +/- 0.8, normals: 0.4 +/- 0.7 (%) and ECP (asthmatics: 827 +/- 491 microg/L, rhinitis: 127 +/- 82 normals: 157 +/- 203). No significant differences were found between healthy subjects and subjects with rhinitis. Eosinophil counts were inversely correlated with FEV1 (r = -0.37) expressed as percentage of predicted, but not significantly correlated with PC20 methacholine (r = -0.28) or blood eosinophils (r = 0.26). CONCLUSIONS: The importance of this study is the confirmation, within important statistical guidelines for a study of reproducibility, that the methods examined are reproducible and valid.

Adult↗
PubMed1995

Uraemic pruritus is not related to plasma histamine concentrations.

Pruritus is a common symptom in uraemic patients and its aetiology is poorly understood, although several factors have been implicated, including high histamine plasma levels. The aim of the study was to evaluate plasma levels of histamine in patients on maintenance haemodialysis in relation to the presence of itching (35 pruritic patients = group A; 50 non-pruritic patients = group B). Furthermore, we compared the values obtained with those of a healthy control group (64 subjects). We observed increased plasma histamine levels in uraemic patients compared with healthy controls. However, no relationship was found between plasma histamine values and itching because groups A and B showed overlapping values and there was no correlation between the intensity of pruritus and plasma histamine concentrations in group A patients. In conclusion, we suggest that there is no evidence for plasma histamine playing a significant part in uraemic pruritus.

Adolescent↗
PubMed1992

[Intranasal absorption of various calcitonin spray preparations].

In a cross-over study performed on 10 patients the intranasal absorption of calcitonin contained in three formulation spray was evaluated. One of them contained biliary acid (sodium taurocholate) as the absorption promoting factor while the other two drugs did not. The dosage of calcitonin in blood was effected by means of radioimmunoassay using salmon calcitonin marked with I126 in competition to the one present in the sample for a limited quantity of specific antibodies for salmon calcitonin. The minimum measurable quantity of calcitonin is 10 pg and the response is linear including values between 20% and 80%. It is observed that the plasmatic concentration of calcitonin dosed in different times after administration of the drug containing sodium taurocholate are always significantly higher (Student "t" test for unpaired data, p less than 0.005) than the measurements after administration of the other two drugs. They are about 8 times higher at the first half an hour, about 6 times after an hour and again double at the second hour. The AUC calculated for sodium taurocholate containing drug (1629 pg/ml/h) results significantly higher in relation to the other two drugs (1133 and 926 pg/ml/h) indicating a better bio-availability of calcitonin contained in that spray. The relative bioavailability between calcitonin spray with sodium taurocholate and the other two drugs in reference resulted to 144% and 176%. The presence of a transmucosal absorption promoting factor at the level of a nasal mucosa, represented in this case by sodium taurocholate, enhances significantly the absorption and the bioavailability of calcitonin present in the formulation spray.

Administration, Intranasal↗
PubMed1988

[Vibration-induced angiopathy: significance of urinary beta-thromboglobulin increase after cold test].

Twenty subjects working with tools generating 100-400 Hz vibrations were submitted to volumetric pulse-plethysmography with cold Test (C.T.) and to the measurement of BTGU, a thromboxane urinary catabolite. After C.T. an increase of BTGU was observed, which attained statistical significance in the subgroup with the most evident plethysmographic modifications. The meaning of these findings is discussed, also in the light their apparent contrast with some literature data. The AA believe that the prostaglandin balance can actually play a role in the pathogenesis of C.T.-induces vasomotor changes, if the tools used generate a sufficiently high number of Hz and if the workers are still rather young. This last condition corresponds to a greater intactness of endothelia and thus to the ability to modulate the vasomotor response ("hunting reaction"). This would lead to the activation of more complex pathogenetic mechanism (also biohumoral ones) among which is thromboxane release.

Adult↗
PubMed1988

[Evaluation of a new multi-RAST method in the screening of allergy to inhalants].

Sera from 1040 adult patients were tested by a new multi-RAST test and PRIST to determine the efficiency of each test in a screening for allergy to inhalants. The patients had been referred to our Institutions for allergological evaluation of respiratory diseases. All the patients had been thoroughly investigated by clinical history, skin prick test and RAST. In 505 a diagnosis of respiratory allergy to one or more inhalants allergens was established, while in 535 a diagnosis of atopy was not confirmed. The new multiRAST test consented to correctly detect 464 out of 505 atopic patients (efficiency 92%) and 517 out of 535 non atopic patients (efficiency 97%). PRIST showed in both cases a minor efficiency (71% in detecting atopy and 77% in detecting non atopy).

Adult↗
PubMed1984

[Changes in spontaneous platelet aggregation induced by the ambient temperature].

The diagnostic meaning of the functional platelets modifications (particularly those of spontaneous platelet aggregation = P.A.) in cardiovascular pathology has been recalled. It is emphasized that, in order to have significantly predictable data on eventual pathological alterations in case of deviations of values considered normal, one has to use methods that do not differ from the real haemorheological conditions. A research has therefore been made with the purpose to evaluate the influence that variations of temperature may have on the samples collected and left to sediment (for the separation of the PRP) and the subsequent modifications of P.A. The research has been made in double on plasma sedimented at 37 degrees C and at room-temperature on 731 subjects, 289 of which were the casuistic groups for the subsequent statistic elaboration. With similar modalities in other 8 patients the eventual variations in excretion of beta-TG were looked for. The results have shown that there are important variations of the spontaneous P.A. rates, that the difference is always statistically very significant and that lowering the temperature of the samples favors an increase in beta-TG excretion . The Authors think therefore that only the sedimentation at 37 degrees C issues a plasma usefull for the further performing of platelets tests, while in the plasma obtained with sedimentation at room-temperature the platelets are perhaps already stimulated to an activation (and subsequently an aggregation) higher than the real one. Data obtained from a homogeneous group of subjects, healthy from a clinical point of view, allowed to fix the new range of normal values within 3% of aggregability . The mechanisms that lead to such different results are discussed. Emphasis is put on the fact that the spontaneous P.A. determined by the means mentioned seems satisfactorily near to the real clinical conditions. That's why the hypothesis arises that also other tests concerning platelet functions could be negatively influenced if they have room-temperature as a condition for plasma separation.

Adult↗
PubMedDate not supplied

A multi-allergen ELISA screening method. Comparison with Pharmacia CAP system and Phazet skin prick test.

Eighty consecutive subjects, coming to our service as suffering from conjunctivitis and/or rhinitis and/or asthma, were investigated by a new multi-allergen enzymatic screening immunoassay (Profilo, Bio-Allergy, Rome, Italy) regarding to serum specific IgE for groups of inhalant allergens (Dermatophagoides, Parietaria, grasses, trees, animal danders). These groups include allergens which are most frequently responsible of allergy in our country. Indices of diagnostic accuracy of this assay were analyzed in relation to skin prick test (SPT, Phazet, Pharmacia), as in vivo reference test, and Pharmacia CAP System, as in vitro reference test, comparing the results achieved by these tests in the same group of subjects. Profilo showed high significant (p < 0.0005) correlations and satisfactory indices of diagnostic accuracy (sensitivity, specificity, predictive values of positive and negative, and efficiency) for the tested allergens with reference to both Phazet SPT and CAP System. In addition, the method appeared very rapid and simple, so that it could be performed in the physician's office.

Adolescent↗
PubMedDate not supplied

[Angiopathy caused by vibrating tools: cold test and prostaglandin balance].

A study was made on a group of workers occupationally exposed to tools producing medium-to-low frequency vibrations, and on a comparable control group. The subjects underwent a plethysmographic examination with the cold test, which revealed a greater number of sphygmic alterations in the exposed group; at the same time spontaneous platelet aggregation, blood levels of 6-K-PGF-1 alpha and TXB2 and urinary levels of BTGU were determined in basal conditions and after the cold test. Except for the slight, and not statistically significant, increase in TXB2, the results did not reveal any alterations in the constituents of the prostaglandin balance after the cold test. This therefore indicates that biohumoral changes of this type were not involved in producing cold-induced vasomotor alterations in the group under study. However, further investigations are recommended which will take account of the age and working history of the subjects, and particularly of the physical characteristics of the vibrations produced by the tools used, especially the Hz number.

6-Ketoprostaglandin F1 alpha↗