Biomedical subjects

V de Leonardis

Publications and source records attributed to V de Leonardis.

22 records · Page 2Linked to original sources

PubMedDate not supplied

[Patterns of ventricular late potentials in systemic sclerosis: a noninvasive method in the study of cardiac involvement].

The aim of our study was to ascertain the prevalence of ventricular late potentials (VLP) in systemic sclerosis (SSc) and their correlation with the immunologic patterns and cutaneous and pulmonary involvement of the disease. Ventricular late potentials, which are low-amplitude high-frequency signals present in the terminal portion of the QRS complex, express the delayed and fragmented depolarization of ventricular myocardial fibers. Observed in myocardial interstitial fibrosis, they are characteristic of the myocardial alterations occurring in SSc. Twenty-six patients with SSc (1 man, 25 women) with a confirmed lack of cardiac involvement (negative history and normal clinical, electrocardiographic, and echocardiographic findings) underwent signal averaged high resolution electrocardiography. Pulmonary involvement was evaluated by pulmonary function tests and high resolution computed tomography. The degree of cutaneous involvement was assessed by skin score. In the patients with SSc, VLP presence with time-domain analysis was 30.8% when a 25-250 Hz pass-band filter was used and 26.9% when a 40-250 Hz pass-band filter was used whereas with frequency domain analysis it was 23.1%. Ventricular late potentials were confirmed in 7.7% of the control subjects, no matter what filter or technique was used. No significant correlations among VLP, pulmonary involvement, skin score and specific antibody patterns were found. Although this technique requires further consolidation, it seems to have the potential for use as an early index of myocardial fibrosis.

Adult↗

PubMedDate not supplied

Vascular damage and not hypertension per se influences endothelin-1 plasma levels in patients with non insulin dependent diabetes mellitus.

Several reports indicate higher endothelin-1 (ET-1) levels in patients with non insulin dependent diabetes mellitus (NIDDM), although this finding has not been confirmed by other studies. The discrepancy may be partially explained by the frequent coexistence in NIDDM patients of other pathologies, such as essential hypertension, and by the presence of diabetic vascular complications or renal failure, able, per se, to increase ET-1 circulating levels. This study aimed to evaluate the influence of arterial hypertension and/or of diabetic angiopathy on ET-1 circulating levels in a group of NIDDM patients. We measured ET-1 plasma concentrations in three groups of subjects: a) 22 NIDDM patients with or without hypertension and with or without vascular complications; b) 11 hypertensive patients; c) 14 age-matched healthy volunteers. Plasma ET-1 concentrations were significantly higher in NIDDM patients with angiopathy (7.3 +/- 0.7 pg/ml, mean +/- Standard Error; p < 0.001) than diabetics without angiopathy (4.4 +/- 0.53 pg/ml), hypertensive patients (4.7 +/- 0.85 pg/ml) and healthy subjects (3.1 +/- 0.19 pg/ml). This report indicates that increased plasma ET-1 levels in NIDDM patients may be ascribed only to those with vascular compliances, while hypertension, per se, does not affect ET-1 plasma levels in these patients.

Aged↗

PubMedDate not supplied

Serum beta-endorphin increase after intravenous histamine treatment of chronic daily headache.

Histamine is able to induce spontaneous-like headache attacks in migraine and cluster headache subjects. Therefore, it has been considered as a possible agent in the pathogenesis of headache. Histamine desensitization is used for the treatment of cluster and other chronic headaches like migrains with interparoxysmal headache. However, it is unknown whether desensitization plays a role in headache improvement. Since a disfunction of the opioid system has been considered responsible for idiopathic headache and since low beta-endorphin levels have been demonstrated in some idiopathic headaches, particularly in migraine with interparoxysmal headache, we planned this study to verify if histamine therapy is able to modify serum beta-endorphin concentrations. For this purpose, we studied 24 healthy control subjects and 36 patients suffering from migraine with interparoxysmal headache refractory to conventional therapies. Patients showed baseline serum beta-endorphin levels significantly lower than healthy control subjects and treatment with histamine for 15 days increased their beta-endorphin concentrations. We believe that histamine treatment can activate the opioid endogenous system. However, the therapeutic effect of histamine remains to be verified by evaluating the correlation between beta-endorphin levels and headache improvement.

Adult↗

PubMedDate not supplied

Melatonin as biological response modifier in cancer patients.

The neuroendocrine system modulates the immune response through neuropeptides and neurohormones, findings which point to the existence of a neuro-endocrine-immune system regulatory axis. At the same time, there is growing evidence that the pineal gland has anti-neoplastic properties, which include the action of its principal hormone, melatonin (MLT), on the immune system through the release of cytokines by activated T-cells and monocytes. The present study was carried out on 31 patients (19 males and 12 females, age range 46-73 years) with advanced solid tumors (7 gastric, 9 enteric, 8 renal, 5 bladder, 2 prostate) who either failed to respond to chemotherapy and radiotherapy or showed insignificant responses and were therefore shifted to MLT therapy (10 mg/die orally for 3 months). We obtained blood samples just before the start of MLT administration and after 30 days of therapy. Plasma was collected in EDTA tubes on ice, immediately centrifuged at 4 degrees C and stored frozen at -80 degrees C; samples were measured by immunoradiometric assays (Medgenix-Fleurus, Belgium) for tumor necrosis factor alpha (TNF), interleukin-1, 2 and 6 (IL-1, IL-2, IL-6) and interferon gamma (IFN). We used Student's paired t-test to compare each patient's cytokine circulating levels before and after MLT administration and found a significant differences (p < 0.05). After 3 months of therapy, none of our patients displayed adverse reactions to MLT or had to discontinue treatment. Nineteen patients (61%) showed disease progression. The other 12 (39%), however, achieved disease stabilization with no further growth of either the primary tumor or of secondaries; moreover, they experienced an improvement in their general well-being, in terms of Tchekmedyian's criteria, associated with a significative decrease of IL-6 circulating levels. These findings are consistent with the hypothesis that MLT modulates immune function in cancer patients by activating the cytokine system which exerts growth-inhibitory properties over a wide range of tumor cell types. Furthermore, by stimulating the cytotoxic activity of macrophages and monocytes, MLT plays a critical role in host defence against the progression of neoplasia.

Adult↗