Human platelet glycocalicin purification by phenyl boronate affinity chromatography coupled to anion-exchange high-performance liquid chromatography.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to B Bizzi.
Explore the source record for details and available documents.
Four pregnant women with antithrombin III congenital deficiency underwent thrombosis prophylaxis including oral anticoagulants administered from the 16-18th week to the 36-37th week of pregnancy, subcutaneous heparin before the 16-18th week and after the 36-37th week, and a single infusion of AT III concentrate in the peripartum period in order to obtain a minimal level of 0.8 U/ml of AT III functional activity. The level of circulating AT III after the concentrate infusion needs to be evaluated by functional methods, because of a consistent amount in the concentrates of inactive AT III immunoreactive material. No thrombotic or haemorrhagic complication occurred after starting prophylaxis in any woman either in any newborn.
A patient with congenital protein-C deficiency was treated with stanozolol for 8 weeks to increase circulating levels of protein C. A rise in protein C was achieved, accompanied by an increase in factor II, factor X, antithrombin III, and protein S; but at the 8th week the patient suffered a transient ischemia attack.
A factor X molecular variant was identified in a 13-year-old girl affected by a bleeding tendency. Factor X antigen levels and activation by Russel's viper venom (tested both by clotting and amidolytic assays) were normal. Factor X crossed immunoelectrophoresis was found to be identical to that of the control plasma. Factor X functional activity was low (3% of the normal) if tested by PTT-derived assays, whereas it was found at intermediate levels (about 30-50% of the normal) if measured by prothrombin time-derived assays. The defect in the extrinsic activation was more clearly disclosed using as activating agent thromboplastin from ox brain. The factor X of the patient was completely adsorbed by aluminum hydroxide. The parents of the propositus (first degree cousins) showed factor X functional levels compatible with a condition of heterozygosity for the abnormality. This factor X molecular variant appears different from the other ones so far described and was named 'Factor X Roma'.
Explore the source record for details and available documents.
The case of a patient with myelofibrosis who developed polycythaemia vera after corticosteroid therapy, splenectomy and Busulphan therapy is reported. The possible pathogenetic role of each of these agents is discussed.
Patients with myeloproliferative disorders (MPD) are known to have some abnormalities of platelet glycoproteins (Gp). Quantitative changes of the Gp Ib, IIb-IIIa, and/or their glucidic content have been reported. Since the Gp IIb-IIIa complex plays a major role in fibrinogen binding by activated platelets, we measured the platelet fibrinogen affinity in nine patients with polycythemia vera (PV) and one subject with chronic myeloid leukemia (CML) by the aggregometric method of Marguerie. In all patients the Kd of the platelet fibrinogen reaction was significantly decreased as compared to controls, with evidence in two cases with PV of a heterogeneity of platelet-fibrinogen receptor sites. The measurement of 125I-labeled fibrinogen-platelet binding, performed in seven patients (five PV and two CML), showed receptor populations with increased (Kd1 = 0.58 + 0.3 X 10(7) mol/L) and normal affinity (Kd2 = 5.12 + 3.1 X 10(7) mol/L). These results demonstrate a heterogeneity of platelet-fibrinogen receptors in these patients and may explain the thrombotic diathesis of MPD subjects.
Explore the source record for details and available documents.
A molecular antithrombin III variant (Antithrombin III Roma) with an abnormal pattern of crossed immunoelectrofocusing was further investigated in order to identify the pathological isoforms. AT III crossed immunoelectrofocusing of the whole plasma from the affected patients showed a loop overlapping the peak normally present at pH 4.8-4.6. Affinity chromatography demonstrated the presence of an AT III fraction totally lacking in heparin affinity. Crossed immunoelectrophoresis on heparin-agarose (H-CIE) and crossed immunoelectrofocusing (CIEF) runs performed on the fractions obtained by heparin-agarose affinity chromatography confirmed that the functional defect was exclusively related to the pathological isoantithrombin (pH 4.8-4.6), which was also devoid of any progressive activity. The AT III fraction with normal affinity to heparin displayed H-CIE and CIEF patterns identical to the control AT III.
Antithrombin III (AT III) plasma levels were investigated in 18 full term neonates and 14 healthy preterm neonates. A control group of 20 healthy adults was also studied. AT III was measured as antigen concentration (Ag) and antithrombin or anti-factor Xa heparin cofactor (H.C.) activities. Crossed immunoelectrophoresis on heparin-agarose (H-CIE) was carried out on plasma samples; moreover the distribution of isoantithrombins was investigated on whole plasma by a technique of crossed immunoelectrofocusing (CIEF). AT III plasma levels in full term infants were significantly lower as compared to the adult values. The preterm newborns group showed a further significant decrease in AT III levels as compared to the full term neonates. In all infants AT III H-CIE runs displayed a single fast moving anodal peak, so that a normal binding to heparin was demonstrated. The CIEF AT III plasma pattern of the adults as well as of all neonates displayed three major peaks at pH range 5.2-4.9, a small amount of AT III at pH 4.9-4.8 and a minor peak at pH 4.8-4.6, so that it was concluded that the isoantithrombins plasma distribution in neonatal age is identical to that of the adult subjects. Four neonates whose mothers were affected by AT III congenital defect were also investigated: diagnosis of congenital deficiency was established in three cases.
The Technicon H*1 haematology system is provided with a new method for basophil count, neutrophil lobularity assessment and detection of blasts in peripheral blood through automated measurement of nuclear density. We compared the results of the H*1 blast flag with those of the microscope examination in 131 peripheral blood samples from 43 patients with acute leukaemia in different phases of their disease, to determine the degree of sensitivity and specificity of the system in this setting. In six patients at diagnosis or in overt relapse, all having large percentages of blasts at the manual differential count, a typical deformation of the profile of the mononuclear cell population on the display was consistently observed, regardless of the morphological subtype of leukaemic cell which was involved. Amongst 34 samples with 4-95% morphologically recognizable blasts on the peripheral blood film, the sensitivity of the system was 100% with no false negatives at all. In 43 samples, on the other hand, the H*1 blast flag was positive in the absence of any morphological evidence of blasts on the smear. These 'false positives', however, were always obtained from leucopenic patients who had more than 12% blast infiltration in the bone marrow, compared to the 0-6% value that was found in patients with a negative H*1 blast flag. These results suggest that the H*1 system is a highly sensitive tool for the detection in peripheral blood of even small concentration of leukaemic cells, which escape morphological identification.
An abnormal AT III variant was found in five members from a family where a high incidence of thromboembolism occurred. In all the affected subjects AT III antigen concentration was normal, whereas antithrombin and antifactor Xa progressive activities as well as heparin cofactor activities were low. Crossed immunoelectrophoresis performed either in absence or in presence of heparin showed a normal plasma pattern. Further chromatographic investigations showed a normal affinity to heparin. An abnormal plasma pattern was evidentiated by crossed immunoelectrofocusing throughout all the AT III pH range. These data are consistent with the presence of an abnormal AT III variant with a defective binding to serine proteases and clearly identifiable only by crossed immunoelectrofocusing. This variant appeared different from the other qualitative AT III defects so far described and was named 'Antithrombin III Pescara'.
Antithrombin III (AT III) functional levels are much lower in serum than in plasma; during oral anticoagulation this difference is reduced. Plasma and serum of 172 patients taking vitamin K antagonists were tested for AT III antigen and both AT III heparin cofactor and anti-Xa heparin cofactor. Crossed immunoelectrophoresis of AT III on heparin-agarose was also carried out in plasma and serum. The patients were divided into four groups: (1) international normalized ratio (INR) 9.3-4.1, n = 25; (2) INR 4.0-2.5, n = 73; (3) INR 2.4-2.0, n = 40, and (4) INR 1.9-1.5, n = 34. 66 healthy subjects were used as controls. Plasma levels of AT III antigen, AT III heparin cofactor, and anti-Xa heparin cofactor were the same in all groups. In all groups all serum AT III parameters were higher than in controls; crossed immunoelectrophoresis of AT III on heparin-agarose indicated that this finding was due to a lower formation of complexed AT III in serum. AT III heparin cofactor serum values were the same whatever the INR over a large range (9.3-1.5); the highest anti-Xa heparin cofactor serum levels were noted in the groups treated more intensely (groups 1 and 2).
Cerebrospinal fluid (CSF) beta-2-microglobulin (B2m) has been proposed as a marker of central nervous system (CNS) involvement in myelo-lymphoproliferative diseases. Recently its reliability has been put in question because of false positive and false negative results. In our study, B2m was measured in 574 CSF samples collected from 74 patients affected by ALL, ANLL or lymphomas; 20 of these patients had CNS-involvement while they were under observation. There was a significant difference in CSF B2m between the patients with and without CNS-involvement (p less than 0.001). No false positive or false negative results were obtained. In 4 cases the rising of CSF B2m was observed 8, 6, 4 and 4 wk before the clinical and laboratory diagnosis of CNS-involvement. In all patients the clinical and laboratory improvement of the neurological disease was associated with a progressive decrease of CSF B2m. Some hypotheses about the origin of CSF B2m are discussed. The authors conclude that CSF B2m is a useful and reliable marker of CNS-involvement in myelo-lymphoproliferative disease.
Fourteen patients with hematologic neoplasia (11 acute myeloid leukemias, 2 non-Hodgkin's lymphomas and 1 blast crisis of chronic myeloid leukemia) who underwent high-dose cytosine arabinoside (HIDARAC) therapy with or without sequential asparaginase (ASNase) were investigated in order to evaluate liver toxicity and a possible decrease in antithrombin III (AT III) plasma level. AT III was found decreased only in patients who received ASNase, whereas HIDARAC alone did not influence AT III levels. It is pointed out that a single dose of ASNase seems to be sufficient to induce a decrease in AT III. A mild and transient liver toxicity due to HIDARAC therapy does not seem to be of any clinical relevance.
Explore the source record for details and available documents.
The cerebrospinal fluid (CSF) and serum beta-2-microglobulin (B-2-m) level was determined in 15 patients affected by lymphoma with and without central nervous system (CNS) involvement and in 15 normal controls. No statistical difference in CNS B-2-m was found between patients affected by lymphoma without CNS involvement and normal subjects. CSF B-2-m was significantly increased (p less than 0.001) in patients with CNS involvement as compared to normal subjects or patients without CNS involvement. These findings suggest that CSF B-2-m can be used as a useful marker of CNS involvement in patients affected by lymphoma.
Explore the source record for details and available documents.