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B Marasini

Publications and source records attributed to B Marasini.

53 records · Page 3Linked to original sources
PubMed1971

Enzymatic and immunochemical determination of plasminogen and plasmin in different physiological and pathological states.

Plasminogen and plasmin have been determined in the same plasma samples in normal subjects and in various physiological and pathological conditions (pregnancy, liver cirrhosis, untreated cancer, and myocardial infarction during treatment with streptokinase) by means of two different methods. These were an enzymatic assay and a new immunochemical assay based on radial immunodiffusion employing cellulose acetate strips.A significant correlation was found in normal subjects. However, in the other conditions marked discrepancies were observed in the results by the two methods. These findings might be related to variations in the functional activity of plasminogen and plasmin in disease.

Adolescent↗
PubMedDate not supplied

Liquid chromatographic determination of free serotonin in human plasma.

The complex background of interfering substances makes plasma pretreatment necessary before performing liquid-chromatographic quantitation of circulating serotonin. We compared two isolation procedures (extraction into butanol and isolation on a weak cation-exchange resin) before chromatography for measuring free serotonin from human plasma. Sensitivity, specificity and recovery were all evaluated. The cation-exchange resin yielded chromatograms with no interfering peaks, was cheaper and took less processing time than butanol extraction. We conclude that the clean-up of human plasma by a cation-exchange resin is suitable and accurate for routine liquid-chromatographic determination of circulating serotonin.

Chromatography, Liquid↗
PubMedDate not supplied

High-performance liquid chromatographic assay of serotonin in human plasma.

A sensitive and reproducible reversed-phase high-performance liquid chromatography with electrochemical detection for determination of serotonin in human plasma is described. The method has an average coefficient of variation of 3.5%; the recovery of serotonin and 5-hydroxy-N-methyltryptamine (internal standard) accounts for 95 +/- 2%. Average serotonin concentrations in platelet-free plasma and in platelet-rich plasma from 21 normal subjects 22-63-year-old) ranged from 0.6 to 4.9 ng/ml (mean 2.8 +/- 1.3 SD) and from 38.3 to 106.5 ng/10(8) platelets (mean 66.8 +/- 18.9 SD), respectively. The release of endogenous serotonin from human aggregating platelets challenged by collagen or adenosine diphosphate has been quantitated.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Quantitative determination of serotonin released from human platelets.

A high-performance liquid chromatographic technique has been used for measuring the amount of endogenous serotonin (5-hydroxytryptamine, 5-HT) released from human platelets stimulated by adenosine diphosphate (ADP) and collagen. Four minutes after challenge both agents induce maximal and similar 5-HT releases corresponding to 14% (ADP) and 17% (collagen) of the intraplatelet 5-HT content. ADP and collagen seem to have different mechanisms of inducing secretion, documented by the different relationship between the release patterns and the optical tracings for aggregation. Endogenous 5-HT release might be useful tool for monitoring states of platelet activation.

Adenosine Diphosphate↗
PubMedDate not supplied

Hereditary angioedema: an appraisal of 104 cases.

One hundred and four patients affected by hereditary angioedema belonging to 31 families have been studied. Twenty-two percent had the variant form related to the deficiency of the functional activity of serum C1 esterase inhibitor. The remaining 78% of patients had the predominant form, characterized by low antigenic levels and low functional activity of serum C1 esterase inhibitor. Attacks of swelling affected the subcutaneous tissue in 86% of patients; the upper airways in 76% of patients, and the bowel mucose in 75% of patients. Before treatment was available the mortality rate was 56%. One or more attacks a month were present in 46% of cases. The infusion of C1 inhibitor concentrate promptly reversed 14 severe attacks without any side effect. Twenty-nine patients were given long term prophylactic treatment with androgen derivatives with full success. Tranexamic acid reduced the frequency of swelling of 70% of the patients.

Adolescent↗
PubMedDate not supplied

Vascular impairment in patients with primary biliary cirrhosis.

Experimental and clinical observation suggest that patients with primary biliary cirrhosis (PBC) have endothelial dysfunction. Postischemic digital blood flow, nailfold capillaroscopy, von Willebrand factor (vWf) and tissue-type plasminogen activator (t-PA) plasma levels were examined in 59 PBC patients. Forty-six subjects (15 with liver diseases other than PBC, 11 hypercholesterolemics, 20 healthy subjects) served as controls. PBC versus healthy controls (209.8 +/- 1.4% and 16.54 +/- 1.44 ng/ml vs. 120.2 +/- 1.4% and 9.91 +/- 1.49 ng/ml; p<0.001) and related to bilirubin (r = 0.38, p<0.02; r = 0.47, p<0.0005, respectively). vWf was also increased in other liver diseases (249.9 +/- 1.7%; p<0.001) and related to bilirubin (r = 0.59, p<0.05). Postischemic finger blood flow negatively correlated with vWf(p<0.05 or less). Our data indicate that PBC patients have microvascular disease. Whether vessels other than those of the fingers were involved remained unclear. vWf and t-PA might reflect a dysfunction of teh hepatic vascular endothelium.

Aged↗
PubMedDate not supplied

Scleroderma heart disease.

Heart disease is a frequent and often severe feature of systemic sclerosis (scleroderma). Cardiomyopathy, with ventricular diastolic dysfunction and arrhythmias, is the most important form, since it is associated with a very poor prognosis. The current challenge is to define its pattern and identify individuals at risk, but evaluation in vivo may be hard to perform. The aim of this review is to provide an update on the clinical aspects of scleroderma heart disease and the early pivotal role that coronary microcirculation dysfunction plays in its development. A discussion of the diagnostic tools now available for this frequently asymptomatic condition will be provided. Treatment options will be reviewed, even though no cure for systemic sclerosis exists, and the current therapy of diastolic dysfunction remains unsatisfactory.

Animals↗
PubMedDate not supplied

[Pulmonary hypertension in autoimmune rheumatic diseases].

OBJECTIVE: Pulmonary hypertension is a severe and rapidly progressive disease, particularly frequent in patients with rheumatic diseases. The aims of this study were the following: to determine the prevalence of pulmonary hypertension in Italian patients with autoimmune rheumatic diseases, and to evaluate if the presence of a rheumatic disease in general, or of a specific autoimmune rheumatic disease, is a risk factor for the development of pulmonary hypertension. PATIENTS AND METHODS: One hundred and thirteen Italian patients with connective tissue diseases (105 females, 8 males), aged 19 to 83 yrs, entered the study. Fifty-one had systemic sclerosis (SSc): 49 were females, 2 males, aged 34 to 83 yrs; 41 had limited cutaneous SSc, 8 diffuse cutaneous SSc, and 2 SSc sine scleroderma. Thirty-three patients had systemic lupus erythematosus (SLE): all but one were females, their age ranged from 19 to 82 yrs. Twenty-five had rheumatoid arthritis (RA): 21 females, 4 males, aged 26 to 45 yrs. Three females and one male, 51-77 yrs, had mixed connective tissue disease (MCTD). Systolic pulmonary arterial pressure (SPAP) was assessed by Doppler echocardiography. RESULTS: Twenty three patients had pulmonary hypertension, which was more frequent in MCTD than in SLE (75% vs 6.1%, p=0.0002) or in AR (20%, p=0.0313). Pulmonary hypertension was more frequent in SSc than in SLE (25.5% vs 6.1%, p=0.0028) and in limited than in diffuse SSc (21.6% vs 3.9%). SPAP was significantly related to age (r=0.35, p=0.0275), with patients with pulmonary hypertension older than patients with normal SPAP (66+/-13 vs 52+/-16 yrs, p=0.0003). CONCLUSIONS: These data show a significant association between pulmonary hypertension and autoimmune rheumatic diseases. Therefore, pulmonary hypertension assessment seems mandatory, at least in MCTD and SSc. However, more studies are needed to clarify the relationship between age and pulmonary hypertension and to verify whether the low prevalence of pulmonary hypertension we found in our SLE patients is related or not to their lower age.

Adult↗