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F Pusineri

Publications and source records attributed to F Pusineri.

8 recordsLinked to original sources
PubMed1990

17 beta-estradiol is the most active component of the conjugated estrogen mixture active on uremic bleeding by a receptor mechanism.

We have reported previously that a mixture of conjugated estrogens which is effective in shortening the prolonged bleeding time in uremic patients is also effective on bleeding time in a rat model of uremia. With the present study we took advantage from such a rat model of chronic uremia and decided to identify the component(s) of the conjugated estrogen mixture responsible for shortening the bleeding time. Moreover, we wanted to clarify whether estrogen effect on primary hemostasis is due to a receptor mechanism and can be neutralized by specific estrogen receptor antagonists such as tamoxifen or clomiphene. Both estrone sulfate and 17 beta-estradiol, but not equilin, were effective in shortening the prolonged bleeding time of uremic rats. 17 beta-Estradiol was the most active component of the mixture, reproducing the time course of bleeding time shortening of the entire mixture (effect lasting 48 hr). The effect of estrone sulfate injection lasted only 24 hr. Tamoxifen and clomiphene pretreatment prevented the shortening of bleeding time induced by conjugated estrogen mixture and its active components. These findings indicate that 17 beta-estradiol is the key compound of the conjugated estrogen mixture effective on bleeding time shortening and that the effect of estrogens on primary hemostasis is mediated by a receptor mechanism.

Animals↗
PubMed1988

Dose-effect and pharmacokinetics of estrogens given to correct bleeding time in uremia.

Conjugated estrogens have a significant and long-lasting effect in shortening bleeding time in patients with end-stage renal disease. The studies so far available indicate that repeated estrogen administrations are necessary to short bleeding time in uremia in a dose range of 95 to 325 mg. With the present study we wanted to establish whether single or repeated doses are required to induce a significant shortening of bleeding time in uremia, and the minimum cumulative dose of conjugated estrogens necessary to control bleeding time for a prolonged period of time, and to check whether the prolonged effect of estrogens on bleeding time in uremia is due to an accumulation of the drug or its metabolites in the blood. Fifteen uremics on chronic hemodialysis were studied. A pilot study carried out in five uremic patients indicated that single or repeated estrogen infusions of 0.3 mg/kg did not significantly influence bleeding time values. Therefore the subsequent studies have been carried out using daily infusion of 0.6 mg/kg. A single estrogen infusion of 0.6 mg/kg shortened bleeding time in all patients. The effect was transient and bleeding time returned to pre-infusion values within 72 hours. A 50% decrease of bleeding time or a shortening of bleeding time more than 30 to 15 minutes or less was obtained in all patients with four or five infusions (0.6 mg/kg) spaced 24 hours apart. The effect lasted for 14 days. At day 25 from the last infusion all the patients had bleeding time values comparable with the pre-infusion ones.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Heparin for hemodialysis: practical guidelines for administration and monitoring.

Anticoagulation of extracorporeal circuit still represents a major problem for hemodialysis units. Uraemic patients are at risk of hemorrhages, so anticoagulant could increase such a risk. On the other hand clotting of extracorporeal circuit may complicate inadequate heparin administration or hemostatic activation by the foreign surfaces. In this article we propose a simple standard for heparin administration and monitoring which allows the theoretical best anticoagulation for extracorporeal circuit. Our data also indicate that the effect of our proposed schedule is not influenced by the type of membrane or dialyser used.

Adult↗
PubMed1983

Deamino-8-D-arginine vasopressin shortens the bleeding time in uremia.

In a randomized double-blind cross-over trial we gave either 1-deamino-8-D-arginine vasopressin or placebo to 12 patients with uremia, hemorrhagic tendencies, and prolonged bleeding times. After vasopressin infusion, all patients had shortened bleeding times, with the effect lasting for at least four hours in most cases. Platelet count, platelet cyclic AMP levels, platelet retention on glass beads, plasma fibronectin, serum thromboxane B2 and residual prothrombin, hematocrit, and plasma osmolarity were unchanged after vasopressin. A consistent post-infusion increase in factor VIII coagulant activity and, to a lesser extent, in factor VIII-related antigen and ristocetin cofactor accompanied the shortening of bleeding time. In addition, vasopressin induced the appearance in plasma of larger von Willebrand-factor multimers than those present in the resting state. The compound was given to nine additional patients with acute or chronic renal failure and prolonged bleeding times, before major surgery or renal biopsy. In these patients, shortening of the bleeding time was associated with normal hemostasis. Our findings indicate that 1-deamino-8-D-arginine vasopressin can be used for temporary correction of bleeding time and may prevent surgical bleeding in patients with uremia.

Adult↗
PubMed1980

Intermittent heparin treatment does not induce hypercoagulability in haemodialysed patients.

Antithrombin-III (AT-III) and factor VIII coagulant (F VIII:C) and antigenic (F VIII:RA) activities have been studied in nine conservatively treated and 26 dialysed uraemic patients. AT-III levels were not significantly different from those of controls in either group. Among dialysed patients, those who had experienced thrombotic occlusions of the vascular accesses could not be distinguished from the remaining patients on the basis of their AT-III levels. Both F VIII:C and F VIII:RA were slightly higher than in controls in conservatively treated patients, but significantly higher in haemodialysed patients, especially in those who had never experienced thrombotic complications of the vascular accesses. No acute changes were observed in either the AT-III or F VIII:C/F VIII:RA ratio in five patients given heparin therapy during a dialytic session or in the interdialytic period. Thus repeated intermittent heparin treatment does not induce a hypercoagulable state in haemodialysed patients.

Adult↗