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A Salvati

Publications and source records attributed to A Salvati.

At least 19 recordsLinked to original sources

Vanadium inhibition of serine and cysteine proteases.

A study was made on the effect of vanadium, in both the tetravalent state in vanadyl sulphate and in the pentavalent state in sodium meta-vanadate, and ortho-vanadate, on the proteolysis of azocasein by two serine proteases, trypsin and subtilisin and two cysteine proteases bromelain and papain. Also the proteolysis of bovine azoalbumin by serine proteases was considered. An inhibitory effect was present in all cases, except meta-vanadate with subtilisin. The oxidation level of vanadium by itself did not determine the inhibition kinetics, which also depended on the type and composition of the vanadium containing molecule and on the enzyme assayed. The pattern of inhibition was similar for proteases belonging to the same class. The highest inhibition was obtained with meta-vanadate on papain and with vanadyl sulphate on bromelain.

Albumins

Plasma catecholamine responses during a personalized physical stress as a dynamic characterization of essential hypertension.

High performance liquid chromatography (HPLC) with electrochemical detection proves to be a reliable method for determination of plasma catecholamines (CA) to assess the possible role of the sympathetic nervous system (SNS) in essential hypertension (EH). The present investigation in a group of 15 normotensive (N) and 13 stable EH patients, homogeneous for age and duration of hypertension, was carried out without treatment in the supine position, up-right position and during a personalized bicycle exercise. Mean blood pressure, mean heart rate, plasma renin activity and plasma aldosterone were also evaluated at the various exertion phases. Norepinephrine (NE) and epinephrine (E) showed a progressive increase in N and in EH patients, reaching the highest values at maximum effort. However, EH patients showed higher E plasma levels than N before maximum effort. Dopamine (DA) reached the highest values in N at maximum effort and in EH patients at recovery time. These findings allow us to foresee the possibility of a better characterization of the SNS role in EH.

Adult

[Relations between ACE inhibition with captopril and atrial natriuretic factor during an acute hemodynamic study].

Aim of this study was to evaluate if captopril treatment may directly alter the trial natriuretic factor (ANF) concentration. Six patients (2 male and 4 female) aged 53 +/- 11 years, with mitral stenosis, and atrial fibrillation, underwent cardiac catheterization in our Institution. The following parameters were evaluated: heart rate, right atrial and pulmonary capillary wedge pressure, aortic and pulmonary pressure, cardiac index, pulmonary and systemic resistances and ANF concentration in coronary sinus, pulmonary, artery, aorta, peripheral vein. All these parameters were measured before and 30 and 60 min after captopril administration (50 mg orally). No hemodynamic changes occurred after captopril administration. No changes in ANF concentration occurred in comparison with baseline levels, after 30 and 60 min in coronary sinus (199.8 +/- 151.5 vs 181.9 +/- 102.5 fmol/ml; 178.4 +/- 95.2 vs 181.9 +/- 102.5 fmol/ml), in pulmonary artery (58.3 +/- 36.6 vs 51.4 +/- 48.8 fmol/ml; 35.5 +/- 16.9 vs 51.4 +/- 48.8 fmol/ml), in aorta (29.7 +/- 22.7 vs 37.5 +/- 26.3 fmol/ml; 25.2 +/- 9.8 vs 37.5 +/- 26.3 fmol/ml); and in peripheral vein (14.6 +/- 7.9 vs 17.3 +/- 9.7 fmol/ml; 16.2 +/- 12.2 vs 17.3 +/- 9.7 fmol/ml). In conclusion our data show that, providing no hemodynamic changes occur, captopril administration does not alter ANF concentration.

Adult

Clinical, biological, and neuropsychological features associated with lateral ventricular enlargement in DSM-III schizophrenic disorder.

Clinical, historical, neuropsychological, and biological correlates of lateral ventricular enlargement on computed tomography (CT scan) were explored in a sample of DSM-III schizophrenics. Patients with enlarged ventricles, as compared with those whose ventricles were normal, presented a longer duration of illness and mean duration of hospitalization, and higher scores on the subscales alogia, affective flattening, and attentional impairment of the Scale for the Assessment of Negative Symptoms (SANS), on the scales self-care, participation in household activities, work performance, and behavior in crises and emergencies of the Disability Assessment Schedule, on the scales rhythm, writing, reading, arithmetic, and left hemisphere of the Luria-Nebraska Neuropsychological Battery, and on the subtests digit span, digit symbol and block design of the Wechsler Adult Intelligence Scale. Furthermore, on the computerized electroencephalogram, beta relative activity was significantly higher in patients with normal ventricles on the right frontal, left frontal, and right central leads. On stepwise discriminant function analysis, the patient groups with enlarged and normal ventricles could be separated statistically, and duration of illness and summary score on the SANS were found to be the best discriminators.

Adolescent

Clinical and neuropsychological correlates of cerebral ventricular enlargement in schizophrenia.

A comprehensive assessment of computed tomography (CT) with respect to clinical, historical and neuropsychological variables has been carried out in a sample of DSM III schizophrenics fairly heterogeneous with respect to duration and severity of illness and in a normal control group matched for sex, age and educational level. The mean value of ventricular brain ratio (VBR) was significantly higher in schizophrenics than controls. Seven patients (21.2%) who had VBRs exceeding 2 SD of the control mean showed a significantly longer duration of illness than the other schizophrenics with significantly higher scores on the subscales alogia, effective flattening and attentional impairment of SANS, on the scales self-care and behaviour in crises and emergencies of DAS, on the scales rhythm, tactile, visual, reading, arithmetic, memory and left hemisphere of LNNB, and on the subtests arithmetic, digit span, digit symbol and block design of WAIS. These results confirm earlier reports of an enlargement of lateral cerebral ventricles in a subset of schizophrenics, and its association with a higher degree of cognitive and neuropsychological impairment, social maladjustment and defectual symptomatology. Moreover, they suggest that the neuropathological process likely to underlie the increase of cerebral ventricular size progresses during the course of the illness rather than predating its onset.

Adolescent

Relationship between CSF noradrenaline levels, C-EEG indicators of activation and psychosis ratings in drug-free schizophrenic patients.

A significant increase of cerebrospinal fluid (CSF) noradrenaline (NA) levels, probably reflecting a rise of central noradrenergic activity, has been observed in a sample of acute schizophrenic patients as compared with a population of subjects without personal or family history of major psychoses. CSF NA levels have been found to be significantly correlated with computerized EEG (C-EEG) indicators of arousal (negative correlation with alpha relative activity and positive correlation with alpha barycentric frequency and beta relative activity in frontal and central leads). No significant relationship has emerged between CSF NA concentration and psychosis ratings on CPRS as well as platelet MAO activity. These findings seems to confirm the link between central noradrenergic hyperactivity and the condition of enhanced arousal of the schizophrenic patient, although the role of this condition in the pathophysiology of schizophrenia (primary phenomenon or non-specific consequence of the stress related to the illness?) remains to be elucidated.

Adolescent

Platelet monoamine oxidase activity in schizophrenia: relationship to family history of the illness and neuroleptic treatment.

Platelet monoamine oxidase (MAO) activity was determined in a large population of drug-free and haloperidol-treated schizophrenic patients and healthy controls and, in a second study, in a sample of schizophrenics after a wash-out period and at different times during treatment with haloperidol. Enzyme activity was significantly decreased in both acute and chronic haloperidol-treated schizophrenics, but not in drug-free schizophrenics, compared with normal controls. No significant difference was observed between drug-free schizophrenics with a family history of the illness and those without such history, and between healthy relatives of schizophrenic patients and normal controls without a family history of schizophrenia. MAO activity was significantly reduced after 14 and 21 days of haloperidol treatment, and such reduction did not correlate with response to treatment. These data strongly support the idea that neuroleptic intake may, at least in part, explain low MAO values repeatedly reported in schizophrenics.

Adolescent