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C Marelli

Publications and source records attributed to C Marelli.

26 records · Page 2Linked to original sources
PubMed1991

In vitro inhibition by defibrotide of monocyte superoxide anion generation: a possible mechanism for the antithrombotic effect of a polydeoxyribonucleotide-derived drug.

In an attempt to elucidate the antithrombotic potential of defibrotide (D) we have evaluated several functions of monocytes from 7 healthy subjects before and after in vitro incubation of the cells with increasing concentrations of this drug. At concentrations as high as 40 micrograms/ml, D hardly affected the expression of both the procoagulant activity of monocytes and the formation of superoxide anion in response to 1 mg/ml zymosan (STZ). In contrast, at concentrations that may be achieved in vivo following the administration of the drug (5-20 micrograms/ml), D impaired in a dose-dependent manner (p less than 0.05) the generation of O-2 in response to N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP, 1 microM) or calcium ionophore A23187 (10 microM). Regardless of the agonist employed, at concentrations between 1 and 5 mM, extracellular Ca2+ had little effect on the impairment of superoxide anion generation by D. In contrast, the inhibitory effect was time-dependent, the maximum impairment (greater than 30%) being observed when the cells were preincubated with the drug for 20 h. These data support the concept that the antithrombotic potential of D involves the ability of the drug to affect the generation of free radicals by leukocytes and suggest that future in vivo studies for the evaluation of the activity of D should take into account the role of monocytes in hemostasis and thrombosis.

Adult↗
PubMed1991

[Efficacy of TTFCA in reducing the ratio between lymphatic and plasma protein concentration in lymphatic and postphlebitic edema].

In subjects with lymphatic problems and postphlebitic edema there is a significant difference in the ratio between lymphatic and plasma concentration of protein (CL/CP) in the foot. Two groups of patients were studied (one group with lymphedema and the other with postphlebitic limbs) in order to assess the CL/CP ratio before and after TTCFA treatment (Centellase). The study confirmed the efficacy of treatment in achieving a significant reduction of CL/CP and distal edema.

Adult↗
PubMed1990

Diabetic neuropathy in db/db mice develops independently of changes in ATPase and aldose reductase. A biochemical and immunohistochemical study.

ATPase activity was investigated in sciatic and optic nerves of female mutant diabetic C57Bl/Ks (db/db) mice and age-matched control mice (db/m and m/m). Nerves from animals aged 50, 70, 125, 180 and 280 days were assayed in vitro for ATPase activity in the presence or absence of ouabain: the ouabain-sensitive fraction contained Na+,K(+)-ATPase. Enzymatic activity was compared within and between age-matched groups. No significant difference in Na+,K(+)-ATPase activity was detected between the diabetic and control mice, whether expressed as mumol Pi/h-1 formed per gramme wet weight or per nerve (protein content). The activity decreased by about 25% in both the sciatic and optic nerves of the oldest animals. These results were strikingly similar in all groups, regardless of the type of nerve examined, confirming that the development of neuropathy in this animal model is unrelated to the postulated derangement of Na+,K(+)-ATPase activity. Among possible explanations, a lack of polyol pathway activation was investigated by staining the sciatic nerves of animals from all groups with the peroxidase-antiperoxidase procedure using a polyclonal antiserum raised against the enzyme aldose reductase. Histological sections of all nerves were consistently negative, suggesting that these animals actually lack the enzyme involved in activating the self-perpetuating metabolic cycle leading to deranged nerve function. The db/db mouse appears to present particular biochemical changes which merit attention with a view to clarifying the pathogenesis of diabetic neuropathy.

Adenosine Triphosphatases↗
PubMed1984

[Not Available].

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Greece, Ancient↗
PubMedDate not supplied

Foam-sclerotherapy, surgery, sclerotherapy, and combined treatment for varicose veins: a 10-year, prospective, randomized, controlled, trial (VEDICO trial).

The study compared, by a prospective, randomized method, 6 treatment options: A: Sclerotherapy; B: High-dose sclerotherapy; C: Multiple ligations; D: Stab avulsion; E: Foam-sclerotherapy; F: Surgery (ligation) followed by sclerotherapy. Results were analyzed 10 years after inclusion and initial treatment. Endpoints of the study were variations in ambulatory venous pressure (AVP), refilling time (RT), presence of duplex-reflux, and number of recurrent or new incompetent venous sites. The number of patients, limbs, and treated venous segments were comparable in the 6 treatment groups, also comparable for age and sex distribution. The occurrence of new varicose veins at 5 years varied from 34% for group F (surgery + sclero) and ligation (C) to 44% for the foam + sclero group (E) and 48% for group A (dose 1 sclero). At 10 years the occurrence of new veins varied from 37% in F to 56% in A. At inclusion AVP was comparable in the different groups. At 10 years the decrease in AVP and the increase in RT (indicating decrease in reflux), was generally comparable in the different groups. Also at 10 years the number of new points of major incompetence was comparable in all treatment groups. These results indicate that, when correctly performed, all treatments may be similarly effective. "Standard," low-dose sclerotherapy appears to be less effective than high-dose sclero and foam-sclerotherapy which may obtain, in selected subjects, results comparable to surgery.

Adult↗
PubMedDate not supplied

Effects of a defibrotide-heparin combination on some measures of haemostasis in healthy volunteers.

In an open-study design five healthy volunteers were first given 2500 IU sodium heparin intravenously and then, after 72 h, another injection of the same dosage of sodium heparin followed immediately by 400 mg defibrotide intravenously. In two separate experiments, prothrombin time, activated partial prothrombin time, antithrombin III, tissue plasminogen activator, its inhibitor and plasma heparin levels were measured at baseline and after 15 min in one experiment, and at baseline and after 2 h in the other experiment. The most important finding was that an interaction exists between heparin and defibrotide on haemostatic activity: activated partial prothrombin time was increased three-fold in volunteers given the defibrotide--heparin combination compared with volunteers given heparin alone. This statistically and clinically significant effect was evident 15 min after administration of defibrotide--heparin and was still present after 2 h. Possible explanations for this effect are discussed briefly.

Adult↗
PubMedDate not supplied

Evaluation of the effects of elastic compression in patients with chronic venous hypertension by laser-Doppler flowmetry.

The evaluation of the effects of elastic compression in patients with venous hypertension and perimalleolar ulceration may be performed using laser-Doppler flowmetry (LDF). This technique may reveal microcirculatory positive variations which are not evident by standard methods as Doppler, plethysmography and ambulatory venous pressure (AVP). In this study we demonstrated the good correlation between AVP values and laser-Doppler parameters, particularly the resting flow and the venous vasomotor response. Also the response of the skin of the perimalleolar region to a local increase of skin temperature was well correlated with AVP parameters. By evaluation of laser-Doppler parameters it was possible to differentiate normals from abnormals (patients with venous hypertension) and it was possible to show variations of microcirculation associated with the decrease of the areas of ulceration after 3 week elastic compression. No significant variations have been recorded by AVP before and after 3 weeks of treatment with elastic compression in 80 patients with venous ulcerations. Laser-Doppler flowmetry was useful to evaluate the positive changes produced by elastic compression.

Adult↗