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F Cavatorta

Publications and source records attributed to F Cavatorta.

At least 19 recordsLinked to original sources
PubMed2006

Formation of self-organized nanoparticles by lecithin/chitosan ionic interaction.

In this work the production of auto-assembled nanoparticles obtained by the mixing of chitosan and lecithin is presented. The size and surface charge of the nanoparticles were studied as function of the weight ratio between components, the viscosity of the polysaccharide and the pH of the colloidal suspension. In order to elucidate the structure of nanoparticles, micro-FT-IR and elastic neutron scattering experiments have been performed. Results evidenced a strong electrostatic interaction between components and a structure that is neither that of homogeneous spheres nor of coated unilamellar vesicles. Preliminary encapsulation experiments with progesterone, as model lipophilic drug, showed good encapsulation efficiencies.

Algorithms↗
PubMed2006

The self-locating catheter: review and cost analysis.

The self-locating catheter invented by Nicola Di Paolo has been increasingly used in Italy and elsewhere since 1994, with about a thousand patients currently implanted every year. Twelve grams of tungsten inserted in the tip of the conventional Tenckhoff catheter during extrusion do not significantly change its form, but suffice to keep the tip firmly in the Douglas cavity. The validity of the new catheter is confirmed by a multicentric controlled study in a large population of peritoneal dialysis patients. This trial showed that patients with the new catheter have fewer episodes of peritonitis, tunnel infection, cuff extrusion, catheter malfunction, obstruction and leakage. This paper outlines the present situation and reports a comparative analysis of the costs of Tenckhoff and self-locating catheters.

Catheterization↗
PubMed2001

Mean square fluctuations of hydrogen atoms and water-biopolymer interactions in hydrated saccharides.

We have used the elastic neutron scattering technique to investigate the dynamics of the two main saccharidic components of starch: amylose and amylopectin. The measurements were carried out in the temperature range of 20 to 320 K and at different hydration levels from the dry state up to 0.47 g saccharide/g D(2)O. In the dry samples, the atomic dynamics is harmonic up to approximately 300 K. In the hydrated samples a "glass-like" transition leading to an anharmonic dynamics is observed. The onset of the anharmonicity occurs at temperatures that increase from approximately 180 K to 260 K upon decreasing hydration from 0.5 to 0.1 g saccharide/g D(2)O. This behavior is qualitatively similar to that observed in hydrated globular proteins, but quantitative differences are present. Assuming a simple asymmetric double-well potential model, the temperature and hydration dependence of the transition have been described in terms of few physical parameters.

Amylopectin↗
PubMed1998

[Subclavian vein stenosis in hemodialysis patients].

Six haemodialyzed patient are reported in whom subclavian and brachiocephalic vein stenosis secondary to subclavian vein catheterization and to permanent cardiac pacemakers led to massive congestive edema of the same arm after an arteriovenous fistula/grafts were created. In view of the fact that subclavian vein stenosis or occlusion is not associated with any clinical findings and it is not possible to identify any predisposing factors associated with the use of the catheters, all patients who have had previous subclavian vein catheters or with permanent pacemakers should be evaluated to determine the patency of the subclavian vein before creation of a permanent access in that arm. Therapeutic answers as to haemodialysis access are discussed in these patients with permanent pacemakers who need haemodialysis. Because of all of these problems, the practice of subclavian cannulation in patients with end-stage renal failure has been discontinued in our centre. Good and reliable technology is now available for repeated short-term or long-term cannulation of the jugular veins for hemodialysis.

Aged↗
PubMed1997

Subclavian vein stenosis: a potentially serious complication in chronic hemodialysis patients with permanent cardiac pacemakers.

We report on two hemodialyzed patients in whom subclavian and brachiocephalic vein stenosis secondary to permanent cardiac pacemakers led to massive congestive edema of the same arm after arteriovenous fistula/grafts were created. Therapeutic solutions regarding hemodialysis access are discussed in these patients with permanent pacemakers requiring hemodialysis.

Aged↗
PubMed1997

[Protein and amino acid metabolism in chronic renal failure].

Some degrees of protein deficiency, suggestive of abnormal protein metabolism, are a well-known feature of chronic renal failure (CRF). Serum albumin concentration, an index of malnutrition and deranged protein metabolism, is frequently decreased relatively early in CRF, even in absence of heavy proteinuria: a more subtle but characteristic abnormality is found in the plasma profile of amino acids. In addition, there is an accumulation in the plasma and tissues of many products of protein metabolism; some of these have been considered as uremic toxins, while others are largely undefined. The origin of abnormalities in protein metabolism are multifactorial. The defect are caused at least partly by dietary deficiency, as well as by the inability of the failing kidney to excrete normal end products of nitrogen and protein metabolism and by the effect of altered uremic milieu on overall metabolism.

Amino Acids↗
PubMed1995

IgA nephropathy associated with Takayasu's arteritis: report of a case and review of the literature.

We report the case of a patient with Takayasu's arteritis, nephrotic syndrome, and pANCA. The kidney biopsy specimen showed the classic features of IgA nephropathy. The course of this patient supports the view that the glomerular and vasculitic involvements of Takayasu's arteritis may result from a common immunologic mechanism, and cases with urinary abnormalities should be carefully followed for the possible coexistence of glomerulonephritis.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1994

Water dynamics in charged and uncharged polysaccharide gels by quasi-elastic neutron scattering.

Using a microeV neutron spectrometer we have studied the mobility of water in gels formed by two polysaccharides: agarose and hyaluronic acid. Agarose is a nearly uncharged polysaccharide; its gels are fairly stiff, quasi-random networks of fibre bundles. Hyaluronic acid is a highly charged polysaccharide capable of retaining large amounts of water in entangled meshworks with unusual rheological properties. We have analysed sets of quasi-elastic lineshapes broadened by two proton populations with different degrees of freedom. The resulting microscopic mobility parameters and their temperature dependence reveal a complex behaviour. The overall effect of the biopolymer network is to increase translational as well as rotational relaxation times, but the changes observed are not dramatic and cannot fully account for the strikingly different macroscopic properties of these gels. Local electrostatic interactions (over 3 to 20 A) do not appear to influence significantly the rheological behaviour.

Journal Article↗
PubMed1993

Internal jugular vein catheterization under echographic guidance.

Having examined the various disadvantages of the catheterization of the central veins performed using the Seldinger technique, we report our results of internal jugular vein catheterization under echographic guidance in 38 uremic patients. The echographic guidance technique allows an easier and safer utilization of the internal jugular vein as vascular access in emergency situations.

Aged↗
PubMed1992

Evaluation of treatments for the vaccination against hepatitis B + thymopentine.

We have studied a series of 43 patients--who were suffering from uremia, subject to hemodialysis treatment, resulting seronegative to the test for HBV and who had never been vaccinated before--considering the HBS antibody as seroconversion index. We subdivided our patients into three groups, according to the treatment employed. First group: French vaccine; 2nd group: French vaccine+thymopenthine; 3rd group: recombining DNA vaccine+thymopentine. From a statistical point of view, in the 3rd group we obtained a significant seroconversion in terms of patients, if compared with the other groups.

Adult↗
PubMed1988

Hemodynamic changes during acetate dialysis, bicarbonate dialysis and hemofiltration.

Twenty uremic patients submitted to three different dialytic procedures (6 patients to acetate dialysis, 8 patients to bicarbonate dialysis, 6 patients to hemofiltration) were monitored in respect to the hemodynamic parameters recorded with a thermistor Swan-Ganz catheter. During acetate dialysis there was an increment of cardiac index (CI) up to positive values (+4.8%), while resistance index (RI) decreased progressively until it reached -16.5%. During bicarbonate dialysis CI, after an initial fall, remained constant and RI increased (+8.6%). During hemofiltration CI decreased constantly throughout the entire procedure while RI increased until +12.9%. We concluded that during diffusive transport the buffer used plays an important role in determining hemodynamic responses to fluid removal; during convective transport vascular resistance increases in spite of acetate.

Acetates↗