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Biomedical subjects

S Coccheri

Publications and source records attributed to S Coccheri.

At least 91 records · Page 5Linked to original sources
PubMed1988

Intravascular coagulation phenomena associated with prevalent fall in fibrinogen and plasminogen during L-asparaginase treatment in leukemic children.

12 children affected by acute lymphoblastic leukemia had higher baseline levels of Normotest, Antithrombin III activity (AT III:A) and antigen (AT III:Ag) than those found in the control group, due to increased liver protein synthesis, as shown by the higher values of 305llbumin. Treatment with L-asparaginase (L-Asp) induced a marked decrease in fibrinogen and plasminogen and only a slight but significant reduction in AT III:A, AT III:Ag, protein C and alpha 2 antiplasmin levels. Platelet counts progressively increased. Each single L-Asp administration acutely induced (as recorded in the 2-hour postadministration samples) a significant increase in fibrinopeptide A values and reduction in several factors and inhibitors, due to activation of coagulation and consumption phenomena. It is suggested that these acute changes, but not the marked and selective reduction in fibrinogen and plasminogen, were partly compensated during L-Asp treatment by an overall increase in clotting and nonclotting protein synthesis in the liver.

Asparaginase↗
PubMed1988

Prostanoid production in varicose veins: evidence for decreased prostacyclin with increased thromboxane A2 and prostaglandin E2 formation.

In this study, formation of arachidonic acid-derived prostanoids was investigated in saphenous veins of varicosed and nonvaricosed patients, all undergoing saphenectomy respectively for varicosis or in preparation for coronary bypass operation. Venous production of prostacyclin (PGI2), thromboxane A2 (TXA2) and prostaglandin E2 (PGE2) was assessed by bioassay and/or radioimmunologic assays as appropriate. Fragments of saphenous veins from varicosed patients produced significantly less PGI2 and more TXA2 and PGE2 than those from the control patients. Addition of arachidonic acid to incubation mixtures dose dependently increased release of these prostanoids, but the levels of PGI2 produced were consistently lower in veins from varicosed patients. No differences were found in varicosed patients between various segments of the same vein, no matter whether macroscopically affected or unaffected. These results demonstrate that the cyclooxygenase pathway in the venous wall of subjects with varicosis is shifted toward lesser formation of PGI2 and higher production of proaggregatory and proinflammatory prostanoids such as PGE2 and TXA2. These biochemical changes may be relevant to inflammation and thrombogenesis in varicosis.

Dinoprostone↗
PubMed1987

Oral anticoagulant therapy control: evidence that INR expression improves the inter-laboratory comparability of results--the Bologna oral anticoagulant control exercise.

The aims of the present study were: 1) interlaboratory normalization of prothrombin time (PT) testing for anticoagulant therapy control through calibration of customary thromboplastins against international reference materials, and 2) "on field" validation of the advantages offered by expression of results as International Normalized Ratio (INR) as opposed to percentage activity. PT tests were carried out over 8 days on the same normal subjects (16) and patients on oral anticoagulants (48) in the 9 laboratories of the Bologna area. The use of customary thromboplastins and coagulometers was maintained in all labs throughout the study. The main results were: 1) the interlaboratory CV of the prothrombin ratios obtained for each sample with all customary thromboplastins (5 different brands) was 15%, but was reduced to levels of 5.8 to 8.9 when using constant thromboplastin brands and batches; 2) the International Sensitivity Index (ISI) values obtained in the different labs were only slightly influenced by the use of different coagulometers; 3) comparable ISI values were obtained through direct calibration with the international reference material and through intermediate calibration with a locally selected standard; 4) use of INR values instead of percentage activity greatly reduced interlaboratory variability and significantly improved uniformity of anticoagulation level measurements, thus reducing the possibility of erroneous prescriptions. The Bologna exercise is therefore of educational value for laboratory and community doctors of the area in understanding and accepting the INR system.

Administration, Oral↗
PubMed1987

Effects of iloprost (ZK 36374), a prostacyclin derivative, on platelet function after ischaemic exercise in patients with stable angina pectoris.

The effect of a chemically stable prostacyclin analogue (Iloprost) on platelet function was investigated in a controlled study in patients with angiographically confirmed stable angina pectoris after ischaemic exercise. In placebo experiments, ADP platelet aggregation was increased after exercise only when measured in whole blood and not in PRP. While plasma thromboxane B2 levels were unchanged, those of 6-keto PGF1 alpha were significantly although transiently increased after exercise. Iloprost displayed a potent antiaggregating activity in PRP and also reversed platelet hyperaggregation occurring in whole blood determinations after exercise. Plasma thromboxane B2 levels were significantly reduced but occasionally a rebound increase occurred 30 min. after end of the infusion. In contrast plasma level of 6-keto PGF1 alpha did not change after Iloprost and its recorded post-exercise increase was counteracted, thus suggesting a negative feed-back mechanism between Iloprost and natural prostacyclin. The data also suggest that degradation of the analogue is probably accomplished through pathways different from those of PGI2.

6-Ketoprostaglandin F1 alpha↗
PubMed1986

Blood coagulation changes in homocystinuria: effects of pyridoxine and other specific therapy.

The aim of this study was to investigate the blood coagulation changes in three patients with homocystinuria, in baseline condition and during therapy. At baseline, antithrombin III activity and factor VII levels were reduced in all three patients; antithrombin III protein and protein C antigen were also slightly lowered in one patient, and factor X in another. beta-Thromboglobulin, a measure of platelet activation, was increased in one case. During pyridoxine treatment, antithrombin III activity was rapidly restored to normal; factor VII increased and beta-thromboglobulin decreased. These data suggest that, in addition to platelet activation, abnormalities of blood clotting, and particularly reduction of antithrombin III, may play a role in the thrombotic tendency associated with homocystinuria. The nature of these clotting alterations is still uncertain, but their improvement during active metabolic treatment suggests that the defect in amino acid transsulfuration of homocystinuria may directly affect synthesis or activity of some liver-dependent clotting factors.

Adolescent↗
PubMed1985

[Significance of the rheological properties of blood in peripheral vascular pathology].

The rationale of the hemorheologic approach to the pathophysiological knowledge and to the treatment of obstructive arterial diseases of the limbs is discussed in this paper. Indeed, the hemodynamic concepts are the natural frame in which the hemorheologic phenomena have to be considered. Proceeding from this background, it seems evident that the viscosity of blood and its major determinants have a limited role in the regulation of blood flow and pressure gradient through a stenotic artery. On the contrary, viscosity factors are of outstanding significance in the regulation of blood flow in the microcirculation, especially in presence of a reduced perfusion pressure and of exhausted arteriolar vasodilation capacity. Consequently, therapeutic measures capable of modifying one or more viscosity determinants may improve blood flow in the microcirculation of territories related to a stenotic artery. Baseline alterations of viscosity or viscosity determinants may be found in patients with obstructive arterial disease, being classified as primary, associated or secondary to arterial obstruction and ischemic damage. However, the presence of such baseline changes is not relevant to the indication of hemorheologic treatments.

Arterial Occlusive Diseases↗
PubMed1984

Changes in the rheologic properties of blood after a high altitude expedition.

The changes in blood rheologic properties induced by exposure to high altitude plus heavy and prolonged physical strain were investigated in 14 climbers of an Italian expedition to Himalaya (maximum altitude reached m 7350). In blood samples collected immediately after return, alterations of some haemorheologic parameters were observed in comparison with baseline values, and namely an increase in relative blood viscosity, fibrinogen and erythrocyte filtration time along with a fall in platelet count. Treatment with a drug acting on the red cell deformability (Pentoxifylline) appeared to prevent the changes in blood viscosity and erythrocyte filterability. In the 9 climbers whom we were able to re-examine after three months, all altered parameters were found to be restored to baseline values. These results contribute to the knowledge of the pathogenesis of high altitude disease and stress the significance of altered haemorheology as one of the mechanisms possibly involved in the vascular events observed in this condition.

Adult↗
PubMed1982

Significance of plasma fibrinopeptide A and high molecular weight fibrinogen in patients with liver cirrhosis.

Plasma fibrinopeptide A (FPA) was measured in 50 patients with liver cirrhosis divided into 'moderate' or 'severe' cirrhotics according to standard clinical and laboratory criteria. FPA was significantly higher than in normal controls although no relation to the severity of disease was found. After a single intravenous administration of heparin there was a significant decrease in FPA levels in the patients. High molecular weight fibrinogen (HMWF) was also determined for some of the patients and was significantly greater than in the normal controls. However, there was no correlation between FPA and HMWF. The greater values of FPA and their responses to heparin indicate that there is increased thrombin formation in a number of patients with liver cirrhosis, with no apparent relation to the severity of the disease.

Female↗
PubMed1982

Hemostatic balance alterations in obese children.

Fibrinolytic response to venous occlusion and other clotting parameters were studied in 34 obese children and 16 controls. The obese children (mean age 9 2/12 years) had a mean overweight of 51.8% +/- 15.6, higher blood glucose and cholesterol levels, and increased baseline and glucose-induced insulinemia. However, baseline ELT did not differ significantly; ELT after 5 min venous occlusion was 203.2 +/- 110.9 min in the obese children and 114.7 +/- 67.9 min in the control group (p less than 0.01) with a mean percent decrease respectively of 14.9% and 29.2%. Poor fibrinolytic responders did not correlate with age, overweight, or metabolic indices. Lower levels of ATIII (p less than 0.01) and no changes in F VIII: C and F VIII: R Ag were also found in the obese. Furthermore, in a larger group of 84 prepubertal obese children (mean age 10 years; mean overweight 48.2%) and in 39 normal prepubertal children (mean age 10 4/12 years) we also studied platelet aggregation capacity according to Breddin. This parameter was altered in a high proportion of the obese children (p less than 0.05). The obese children were also poor fibrinolytic responders, similarly to obese adults, and exhibited early alteration of the clotting balance.

Antigens↗
PubMed1979

Investigations on intravascular coagulation in liver disease: souble fibrin monomer complexes in liver cirrhosis.

Souble fibrin monomer complexes (SFMC) have been quantitated in 18 patients with liver cirrhosis by means of plasma gel filtration on an agarose column. The concentration of SFMC (as related to total fibrinogen) was increased in cirrhotic patients. The difference between controls and patients, as well as the difference between compensated and decompensated cirrhotic subjects, was statisically significant. Although these data, together with the results of heparin administration in one reported case, suggest intravascular coagulation, some alternative explanations should also be considered.

Bacteriological Techniques↗