Showing papers by "Marche Polytechnic University published in 1992"

Epidemiology of viral hepatitis in dialysis centers: a national survey.

Abstract: Because of the great problem of viral hepatitis in hemodialysis patients, the Italian Society of Nephrology decided to perform a national epidemiologic survey. We contacted 467 nephrological centers by a questionnaire which let us have information on 25,746 uremic patients: 18,338 on HD, 2,250 on PD and 5,176 with kidney transplant, respectively 78.5% of the total Italian dialysed patients and 91.4% of the total transplanted patients. Statistical analyses were performed. HBV infections occur in 7.8% of the patients (2,008 cases) but considering that 485 cases became spontaneously negative, the true overall incidence of chronic carriers falls to 4.9%. The main causes of the infection are reported as transfusions (64.3%) and dialysis environment (12%). The vaccination program performed by 93.2% of the centers, obtained an efficacious seroconversion in 4,626 of 7,790 cases vaccinated: the vaccine currently most utilized is the recombinant type administered by means of 3 versus 4 boosters. In the 2nd part of the survey, we report information concerning the presence of nephropaties associated with HBV infections in nonuremic patients (208 cases). We present and discuss the clinical picture of the nephropaties, the hystologic bioptic pattern and the prognosis of the kidney pathology.

Substance P‐containing pyramidal neurons in the cat somatic sensory cortex

Abstract: Light and electron microscopic immunocytochemical methods were used to verify the possibility that neocortical pyramidal neurons in the first somatic sensory cortex of cats contain substance P. At the light microscopic level, substance P-positive neurons accounted for about 3% of all cortical neurons, and the vast majority were nonpyramidal cells. However, 10% of substance P-positive neurons had a large conical cell body, a prominent apical dendrite directed toward the pia, and basal dendrites, thus suggesting they are pyramidal neurons. These neurons were in layers III and V. At the electron microscopic level, the majority of immunoreactive axon terminals formed symmetric synapses, but some substance P-positive axon terminals made asymmetric synapses. Labelled dendritic spines were also present. Combined retrograde transport-immunocytochemical experiments were also carried out to study whether substance P-positive neurons are projection neurons. Colloidal gold-labelled wheat germ agglutinin conjugated to enzymatically inactive horseradish peroxidase was injected either in the first somatic sensory cortex or in the dorsal column nuclei. In the somatic sensory cortex contralateral to the injection sites, a few substance P-positive neurons in layers III and V also contained black granules, indicative of retrograde transport. This indicates that some substance P-positive neurons project to cortical and subcortical targets. We have therefore identified a subpopulation of substance P-positive neurons that have most of the features of pyramidal neurons, are the probable source of immunoreactive axon terminals forming asymmetric synapses on dendritic spines, and project to the contralateral somatic sensory cortex and dorsal column nuclei. These characteristics fulfill the criteria required for classifying a cortical neuron as pyramidal.

GM1 Ganglioside Therapy in Acute Ischemic Stroke

Abstract: A double-blind, randomized, placebo-controlled clinical trial, involving two Italian centers, was carried out to evaluate the efficacy and safety of the monosialoganglioside GM1 in acute ischemic stro

Ultrastructural analysis of the adaptation of articular cartilage to mechanical stimulation.

Abstract: Ultrastructural analysis was conducted on samples of articular cartilage taken from both load-bearing and non-load-bearing areas with the aim of evaluating the morphologic adaptation of the articular cartilage to mechanical stimulation and identifying the mechanisms of interaction of the chondrocyte and the matrix. Through this analysis we were able to better define the adaptation process of the cartilage as well as the modalities of mechanical stress transmission. We believe that the complex formed by the chondrocyte, the pericellular matrix, and the pericellular capsule constitutes the biomechanical unit of the articular cartilage which serves as the sensor and transducer of mechanical stress. The arrangement of the collagen fibers and the proteoglycans which make up the pericellular capsule and membrane around the chondrocyte can be compared, from a mechanical standpoint, to a dynamic structure constructed in order to absorb the load stresses and protect the internal environment. From a biological standpoint, these are comparable to an extracellular-scaffold constructed with the aim of mediating the interaction between the chondrocyte and the territorial and inter-territorial compartments.

High levels of plasma atrial natriuretic factor and impaired left ventricular diastolic function in hypertensives without left ventricular hypertrophy.

Abstract: OBJECTIVE To seek possible correlations between plasma atrial natriuretic factor (ANF) and left ventricular diastolic function (LVDF) in hypertensive patients. DESIGN Since LVDF abnormalities can be detected in patients with normal left ventricular mass, we studied a group of hypertensive patients without left ventricular hypertrophy. METHODS Untreated hypertensive patients (n = 23) and normotensive control subjects (n = 19) were studied. LVDF indices were obtained by M-mode and pulsed Doppler echocardiography. Blood samples for plasma ANF were taken in the recumbent position from subjects on normal-sodium intake. RESULTS Plasma ANF levels were significantly higher in hypertensive patients than in normotensive subjects. All indices for systolic function were normal in both normotensive subjects and hypertensive patients. Left atrial diameter was significantly higher for hypertensive patients than for normotensive subjects. Considering LVDF, all indices for ventricular filling were found to be altered, on average, in hypertensive patients, the only exception being peak early velocity. In addition, significant correlations were found between plasma ANF and the pulsed Doppler parameters of left ventricular filling, peak atrial velocity and the peak early:peak atrial velocity ratio. Overall correlations between plasma ANF and left atrial diameter, and between left atrial diameter and left ventricular mass index were also observed. CONCLUSIONS The high levels of plasma ANF observed in our hypertensive patients and their correlation with the LVDF indices (which mainly reflect the atrial contribution to ventricular filling) could be the result of an increased atrial stretch due to diastolic ventricular dysfunction. This may exist in hypertensive patients before the development of ventricular hypertrophy.

MR imaging in the diagnosis of carpal tunnel syndrome.

Abstract: Diagnosis of carpal tunnel syndrome (CTS) is usually made on the basis of clinical and electrophysiologic data. Other tests, however, such as ultrasound and CT, have enabled us to acquire additional information regarding the anatomical definition of the structures inside the carpal tunnel. The superior quality of MRIs soft-tissue definition led us to employ it in cases of median nerve compression at the wrist in order to determine its true diagnostic value. We compared the preoperative electrophysiologic and MRI findings in 23 cases of CTS which had undergone surgical decompression of the median nerve at the wrist. Exact correspondence with the intraoperative findings confirmed the reliability of the anatomical information provided by MRI, yet the same comparison revealed that correct "functional" information could be provided only by the electrophysiologic tests.

Effects of calcium on Na+,K(+)-ATPase isolated from human placenta.

Abstract: It has been reported that Ca2+ can be either stimulatory or inhibitory of the activity of Na+,K(+)-ATPase obtained from different sources. The aim of the present work was to study the effect of increasing concentrations of Ca2+ on Na+,K(+)-ATPase activity and of placenta. The temperature dependence of Na+,K(+)-ATPase activity and of spectral parameters of a spin label paramagnetic maleimide) were also (MSL, 2,2,6,6-tetramethylpiperidin-1-oxyl-4-maleimide) were also investigated in absence and in presence of 2 mM Ca2+. Ca2+ affects positively the enzymatic activity and this effect is evident at all temperature tested. Maleimide spectral parameters are not affected by the presence of 2 mM Ca2+, showing that the microenvironments of SH groups are not modified following ion interactions.