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Factor X Padua: a 'new' congenital factor X abnormality with a defect only in the extrinsic system.

A family with a new factor X defect is reported. The proposita is a 56-year-old female. She is asymptomatic and no consanguinity is present between the parents. The main features of the defect are: prolongation of prothrombin time and derivative tests but normal partial thromboplastin time. Factor X was found to be low (about 25-30% of normal) only if tissue thromboplastins were used in the assay system. Chromogenic substrate S-2222 also yielded decreased factor X levels. However, factor X activity was normal with cephalin and cephalin-RVV mixture. Factor X antigen was normal in three immunological systems (electroimmunoassay, an Elisa method and laser nephelometry). Crossed immunoelectrophoresis and antigen-antibody kinetics recorded in a laser nephelometer failed to show major differences from normal factor X. Both sons of the proposita, the father and other family members showed slightly decreased factor X levels and normal factor X antigen and were considered heterozygous for the abnormality. The toponym factor X Padua is proposed to indicate this peculiar abnormality.

Factor X Deficiency↗

Congenital factor X deficiency in Japan.

Congenital factor X deficiency is a very rare inherited coagulation abnormality. There have been reported 43 cases of this disorder in the world and only 2 cases in Japan. Recently, we have hemostatically and immunologically examined as many as 3 cases of this rare disease, 18-year-old male, 11-year-old male and 6-year-old female. Hemostatic examinations revealed prolonged prothrombin time, partial thromboplastin time and decreased serum thromboplastic activity in these 3 cases. Stypven-cephalin clotting time was also abnormal. Factor X activities of our cases were low when assayed by either tissue thromboplastin and partial thromboplastin or by Stypven-cephalin mixture, which were 2.6, 1.5 and 4.5%, respectively. The half lives of infused factor X were 24, 38.6 and 56 hr, respectively, which are consistent with the data of other authors. Immunological assay of factor X (radioimmunoassay) showed 0.47 microgram/ml in the second case and 0.15 microgram/ml in the third case, from which our cases were considered to be classical factor X deficiency.

Adolescent↗

[Biological supervision of heparin therapy].

Laboratory surveillance of heparin therapy includes a simplied investigation of haemostasis before the treatment (Quick's time, the cephalin-kaolin time, fibrinogen, platelet count) and requires exact adherence to the timetable of injections and taking of samples. According to the degree of hypocoagulability desired, there is a choice between the three tests most often used (Howell's test, heparinaemia, cephalin-kaolin time). For the control of a high degree of hypocoagulability the Howell's time is the best guide. On the other hand, for the surveillance of moderate hypocoagulability (preventive treatment) it is preferable to combine two of these three tests.

Blood Coagulation Tests↗

[The importance of phosphatidylcholine in the binding of anti-D to human erythrocyte ghost membrane (author's transl)].

Incubation of Rh positive ghosts with phospholipase A2 and C abolished the adsorption of Rh antibodies on the ghosts; incubation with phospholipase D, however, did not affect their adsorption and none of these phospholipases affected the adsorption of antibodies of the ABO system. The impairment of antigen-antibody-reaction in Rh positive ghosts treated with phospholipase corresponds to the absence of the antigen-antibody reaction with the membrane protein associated with Rh characteristics in the Schultz-Dale-Test. The chromatogram of the phospholipids extracted from those stromata treated with various phospholipases and those not treated showed different patterns. After incubation with phospholipase-A2 the lecithin and cephalin streaks were reduced and in addition lysophosphatide and fatty acid streaks were detected. In the case of phospholipase C the lecithin and cephalin streaks were further reduced while diglyceride streaks made their appearance. The phospholipid extracts from those stromata treated with phospholipase D and those not treated were identical. Phospholipase C reduced the values of lipid phosphorus more than did phospholipase A2, while phospholipase D did not reduce them at all. This study supports the results of other investigators who have postulated that the Rh antigens are located in a lipoprotein on the membrane of the human erythrocyte. The antigen-antibody-reaction seems to require a precise protein-phospholipid interaction.

Binding Sites, Antibody↗

[Antithrombin III and alpha-2-antiplasmin activities compared with other hemostasis parameters in uncomplicated diabetes mellitus, type 2].

In 40 patients with diabetes mellitus type II without clinical signs of any organ complications and in the respective control group the following indices of hemostasis were assessed: 1) activity of AI-III, 2) activity of alfa-2-AP, 3) fibrinogen, 4) time of fibrinolysis, 5) platelets count, adhesiveness and spontaneous aggregation, 6) kaolin-cephalin and profil stipven-cephalin plasma times. All these indices were normal in uncomplicated diabetes mellitus with the expectation of platelets activity. Stimulation of platelets activity and increase of corresponding parameters appears in diabetes mellitus type II before any other symptoms of angiopathy.

Adult↗

[Effects of injecting urokinase via carotid artery in treatment of cerebral venous sinus thrombosis: an experiment with rabbit models].

OBJECTIVE: To study the effects of injection of urokinase via carotid artery in treatment of cerebral venous sinus thrombosis. METHODS: Thirty-nine New Zealand white rabbits were made into models of cerebral venous sinus thrombosis with the superior sagittal sinus ligated and injected with suspension of cephalin kaolin and cephalin, and then were randomly divided into three groups: control group (n = 15), anticoagulation group (n = 12, infused with heparin 2 mgxkg(-1)xd(-1) via external carotid venous for 5 days), and thrombolysis group (n = 12, injected with urokinase 4000 Uxkg(-1)xd(-1) via carotid artery for 5 days). Laser Doppler scanning was used to determine the local cerebral blood flow before ligation, 20 and 90 min after ligation, and at the end of experiment. Five rabbits of the control group per each of the 3 time points (before ligation, 12 h after ligation, and at the end of experiment) were killed to collect the tissues of cerebral cortex in front of the ligated part to determine the brain water content. All the remaining rabbits were killed within 24 hours after the end of experiment to determine the brain water content and undergo microscopy. RESULTS: The local cerebral blood flow of the thrombolysis group was 94.8% +/- 0.3%, significantly higher than those of the anticoagulation group (88.6% +/- 0.3%) and control group (80.9% +/- 0.3%) (both P < 0.01). The brain water content of the thrombolysis group was 78.9% +/- 0.3%, significantly lower than those of the anticoagulation group (81.8% +/- 0.7%) and control group (82.1% +/- 1.0%) (both P < 0.05). CONCLUSION: Improving the local blood flow and reducing the brain water content, injection of urokinase via carotid artery is effective in treatment of cerebral venous sinus thrombosis.

Animals↗

Meizothrombin formation during factor Xa-catalyzed prothrombin activation. Formation in a purified system and in plasma.

Meizothrombin and thrombin formation were quantitated during factor Xa-catalyzed activation of human prothrombin in reaction systems containing purified proteins and in plasma. In the purified system considerable amounts of meizothrombin accumulated when prothrombin was activated by factor Xa (with or without accessory components) under initial steady state conditions. The ratio of the rates of meizothrombin and thrombin formation was not influenced by variation of the pH, temperature, or ionic strength of the reaction medium. When 2 microM prothrombin was activated by the complete prothrombinase complex (factor Xa, factor Va, Ca2+, and phospholipid) 80-90% of the initially formed reaction product was meizothrombin. Lowering the prothrombin concentration from 2 to 0.03 microM caused a gradual decrease in the ratio of meizothrombin/thrombin formation from 5 to 0.6. When the phosphatidylserine content of the phospholipid vesicles was varied between 20 and 1 mol % and prothrombin activation was analyzed at 2 microM prothrombin the relative amount of meizothrombin formed decreased from 85 to 55%. With platelets, cephalin, or thromboplastin as procoagulant lipid, thrombin was the major reaction product and only 30-40% of the activation product was meizothrombin. We also analyzed complete time courses of prothrombin activation both with purified proteins and in plasma. In reaction systems with purified proteins substantial amounts of meizothrombin accumulated under a wide variety of experimental conditions. However, little or no meizothrombin was detected in plasma in which coagulation was initiated via the extrinsic pathway with thromboplastin or via the intrinsic pathway with kaolin plus phospholipid (cephalin, platelets, or phosphatidylserine-containing vesicles). Thus, thrombin was the only active prothrombin activation product that accumulated during ex vivo coagulation experiments in plasma.

Enzyme Activation↗

Effects of ketorolac tromethamine on hemostasis.

Ketorolac tromethamine is a potent prostaglandin synthetase inhibitor useful in the treatment of postoperative pain. Since it is also known to have antiplatelet properties, we determined the effect of ketorolac, alone and in combination with low-dose heparin, on hemostasis. Each of 12 healthy male volunteers received the following drug combinations on a double-blind, crossover basis: ketorolac dummy/heparin dummy, ketorolac active/heparin dummy, ketorolac active/heparin active, and ketorolac dummy/heparin active. Ketorolac significantly prolonged bleeding time, and inhibited platelet aggregation and platelet thromboxane production. Heparin had no effect on bleeding time or platelet function, but significantly prolonged the kaolin-cephalin clotting time and increased anti-Xa levels. Ketorolac had no effect on the kaolin-cephalin clotting time or anti-Xa levels, and no interaction was found between ketorolac and heparin. The modest prolongation of bleeding time with ketorolac is unlikely to be of any major clinical significance, as the value remained within the normal range in almost all subjects. However, because of its antiplatelet properties, the drug should be used with caution in persons with hemostatic disorders.

Administration, Oral↗

[Immunological disorders of coagulation in habitual abortion. Prospective study].

The physiopathological role of antithromboplastin-type circulating anticoagulants in habitual abortion may be envisaged since the presence of antithromboplastin has been reported in most studies on women at high risk of abortion. To avoid a possible statistical bias, we conducted a prospective study in a sufficiently large group of women with habitual abortion (n = 99) compared with a control group of women with normal fecundity (n = 50). In addition, all women were investigated for lupus symptoms. The circulating antibody was detected by the diluted thromboplastin time and activated cephalin time methods. The results were considered positive when the patient/control diluted thromboplastin time ratio was 1.2 and/or when the increase in activated cephalin time was not corrected by a control plasma. In the patients' group, 10 women (10%) had an anti-thromboplastin type circulating anticoagulant, whereas no circulating anticoagulant could be detected in the control group. Three women with circulating anticoagulant had signs of systemic lupus erythematosus. None of the patients presented with Soulier-Boffa syndrome. These data have established a significant correlation between habitual abortion and circulating anticoagulant whilst avoiding statistical bias. Our results suggest that women with idiopathic habitual abortion should be subjected to systematic immunological exploration and that a small number of them should be followed attentively.

Abortion, Habitual↗

Haemostatic effects of ketorolac with and without concomitant heparin in normal volunteers.

Ketorolac is a potent cyclo-oxygenase inhibitor used for the treatment of postoperative pain. It is known to have anti-platelet properties. The aim of this study was to determine the effect of ketorolac on haemostasis both alone and in combination with low dose heparin in 12 healthy male volunteers. Each volunteer received the following drug combinations in a double blind, placebo controlled, cross over manner: ketorolac placebo/heparin placebo, ketorolac active/heparin placebo, ketorolac active/heparin active and ketorolac placebo/heparin active. Ketorolac significantly prolonged bleeding time, inhibited platelet aggregation to arachidonic acid and collagen and platelet thromboxane production. Heparin had no effect on bleeding time or platelet function, but significantly prolonged the kaolin cephalin clotting time and increased anti-Xa levels. Ketorolac had no effect on the kaolin cephalin clotting time or anti-Xa levels and no interaction was found between ketorolac and heparin in any of the investigations. The prolongation of bleeding time seen with ketorolac is unlikely, to be of any major clinical significance as almost all subjects remained within the normal range; however, it should be used with caution in subjects with haemostatic problems.

Adult↗

[Properties of phospholipase D from Raphanus sativus].

The main properties of phospholipase D from radish roots were studied. The effects of various activators including Ca2+ on the catalytic activity of the enzyme were determined. The necessity for Ca2+ is in a large degree dependent on the type of the prime, as well as on the substrate type. Sodium dodecyl sulfate and diethyl ester can induce lecithine cleavage in the presence of Ca2+, while solid adsorbents, e.g. silicagel, can stimulate the reaction in the absence of Ca2+. The curve of the enzyme hydrolytic activity dependence on pH has two maxima, which depend on the type of the prime. Phospholipase D from radish roots, unlike the enzyme from other plants (cotton, peanut, cabbage, etc.) displays a more pronounced specificity for lecithine as substrate and is weakly active in the reaction with cephaline. Cephaline undergoes splitting by phospholipase D in the absence of Ca2+ as well, despite the fact that Ca2+ are necessary for lecithine hydrolysis. An addition of Ca2+ increases the enzymic affinity for the substrate in all cases studied. Some data on the transalkylating function of the enzyme are given.

Calcium↗

[Subcutaneous recombinant hirudin in the treatment of deep venous thrombosis. A pharmacokinetic study].

Recombinant hirudin (HBW 023) has a pure and specific antithrombotic activity. It could be more effective than heparin in the treatment of deep venous thrombosis. Its half life is about three hours when administered intravenously which requires continuous infusion whereas subcutaneous administration can ensure stable plasma concentrations and antithrombotic activity over a period of approximatively 12 hours. The aim of the study was to check the safety and clinical and radiographic efficacy of recombinant hirudin administered subcutaneously to patients with recent deep venous thrombosis and to analyse the pharmacokinetics of the product and its effects on tests of coagulation. Ten patients were treated with 0.75 mg/kg of subcutaneous recombinant hirudin twice a day for 5 days. Anticoagulation was performed with standard heparin and acenocoumarol. Bilateral phlebography, pulmonary angiography or ventilation and perfusion scintigraphy were carried out before and on the 5th day of recombinant hirudin treatment. The activated cephalin time and standard anticoagulant tests and the plasma kinetics of recombinant hirudin were assayed between the 1st and 12th hour on the first and fifth days of treatment. The clinical course was simple in all but one patient who had a recurrence of pulmonary embolism on the 4th day justifying thrombolytic treatment. No haemorrhagic complications or secondary biological effects were observed. On the 5th day, control phlebography was unchanged or improved in all patients. The peak plasma concentration of recombinant hirudin was observed between the 3rd and the 4th hour following subcutaneous injection. The activated cephalin time was increased in parallel with increased concentrations of recombinant hirudin.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Detection of factor VIII inhibitors with the partial thromboplastin time.

Variations of the partial thromboplastin time (PTT) were tested to determine the best screening method for detection of inhibitors of factor VIII. Variables tested included the duration of preincubation of a mixture of patient plasma and factor VIII source (normal plasma), the ratio of the patient plasma to the normal plasma, and the duration of incubation of the normal plasma-patient plasma mixture with kaolin-cephalin suspension prior to recalcification. The following conclusions were reached: (1) The PTT performed on a mixture of equal amounts of patient and normal plasma without preincubation of the mixture was inadequate to detect many factor VIII inhibitors. (2) Factor VIII inhibitors of more than 0.5 Bethesda units could be detected if the PTT was performed on a mixture of four parts patient plasma and one part normal plasma, with preincubation of the mixture for 60 min at 37 degrees C. (3) Factor VIII inhibitors as weak as 0.1 Bethesda units could be detected if the PTT was performed on a mixture of four parts patient plasma and one part normal plasma incubated with kaolin-cephalin suspension for 120 min at 37 degrees C before recalcification. The last method may make detection of mild factor VIII inhibitors possible in routine clinical laboratories not equipped to perform the more technically difficult Bethesda inhibitor assays.

Factor VIII↗

Combination chemotherapy for breast carcinoma using a combination of cyclophosphamide, methotrexate and 5-fluorouracil (CMF) causes a platelet aggregation defect.

Various coagulation parameters including platelet aggregation were evaluated during the course of treatment in 25 patients with breast carcinoma receiving a combination of cyclophosphamide, methotrexate and 5-fluorouracil (CMF). No significant changes were found in whole blood clotting time (WBCT), prothrombin time (PT), kaolin cephalin clotting time (KCCT), platelet count (PC) and prothrombin consumption index (PCI). The CMF combination induced a significant reduction in platelet factor-3 (PF3) availability and reduction in platelet aggregation to ADP and adrenaline. These defects occurred without development of thrombocytopenia. The changes occurred on the 8th day of chemotherapy and a progressive suppression in platelet aggregation was noted during subsequent follow-up. This acquired abnormality in platelet aggregation and PF3 availability may be responsible for various hemorrhagic manifestations such as mucositis, epistaxis and hemorrhagic cystitis following CMF therapy. Further, these changes precede the onset of life-threatening complication of thrombocytopenia. The study of platelet aggregation should be considered besides platelet counting in patients on CMF combination to assess bleeding diathesis.

Antineoplastic Combined Chemotherapy Protocols↗

Fourier transform infrared spectroscopy as a probe for the study of the hydration of lipid self-assemblies. II. Water binding versus phase transitions.

The gradual hydration of phospholipid films can be effectively probed by Fourier transform infrared (FTIR) spectroscopy (cf. part I of this series). The hydration-induced changes observed for lipid IR-absorption bands are probably composed of contributions arising from the effects of both the direct binding of water molecules and the thereby caused conformational changes and phase transitions in the lipid molecules and assemblies, respectively. In this article, an attempt is made to attribute some of the more indicative spectroscopic results to these molecular and supermolecular processes with a view to separating their individual contributions to the relevant spectroscopic data. This is done by considering a series of suitable PLs consisting of the palmitoyl and oleoyl lecithins, DPPC, DOPC, POPC, and OPPC, and one cephalin, DOPE. This choice of PCs and DOPE means that at room temperature and different degrees of hydration, several phase states including lamellar gel and liquid crystalline as well as certain nonlamellar phases are covered. The separation of the water-binding and phase-transition contributions to the FTIR-spectroscopic data, we believe, is clearly demonstrated by interpreting the hydration-dependent wavenumber shifts of the nu C=O band of the PCs. Carbonyl groups are affected to a more significant degree for lipids arrayed in the L alpha phase than in the gel phase. A number of spectral features reveal the lyotropically triggered chain-melting transition as well as other structural rearrangements of PCs. This is discussed in detail and demonstrates the excellent sensitivity of the FTIR methodology for the study of such systems.

1,2-Dipalmitoylphosphatidylcholine↗

Effect of early blood transfusion on gastrointestinal haemorrhage.

The effect of citrated stored blood on coagulation was studied initially in a pilot study where 25 patients with acute severe gastrointestinal haemorrhage had their whole blood coagulation measured using the Biobridge Impedance Clotting Time (ICT). This demonstrated that there is a hypercoagulable response to haemorrhage which was partially reversed by blood transfusion. Similar changes were noted in Kaolin Cephalin Clotting Times (KCCT). A further 50 patients were then randomized to receive, during the 24 h after admission, either at least 2 units of blood or no blood transfusion unless the haemoglobin fell below 8 g/dl or they were shocked. In the transfused group nine patients re-bled compared with only one in the non-transfused group (P less than 0.01, chi 2 with Yates' correction). Early blood transfusion appears to reverse the hypercoagulable response to haemorrhage thereby encouraging re-bleeding and hence the need for an operation.

Blood Coagulation Disorders↗

Lack of interaction between nizatidine and warfarin during chronic administration.

Nizatidine is a new antagonist of H2 receptors. The nizatidine warfarin interaction was investigated in healthy volunteers during chronic warfarin (mean warfarin dose: 5 +/- 0.9 mg/d) and nizatidine (300 mg/d) administration. Nizatidine coadministration did not increase the prothrombin time, kaolin-cephalin clotting time, and did not modify the activity of clotting factors II, VII, IX, X. Nizatidine did not influence the steady-state plasma warfarin concentration.

Adult↗

Measurement of the rate of thrombin production in human plasma in contact with different materials.

Thrombin production in plasma in contact with various materials was consistent with a first-order autocatalytic model (d[T]/dt = kp[T]; [T] = thrombin concentration, t = time, kp = thrombin production rate constant) since the initial portion of a semilogarithmic plot of thrombin concentration against time was linear. Thrombin concentration was measured in clotting plasma (phospholipid enhanced or platelet-rich plasma) using a fluorogenic substrate (BMCA) by aliquot sampling at various intervals or more conveniently by monitoring cumulative fluorescence. The latter was generated by the action, on BMCA incubated in the clotting plasma, of the thrombin as it was generated. The thrombin concentration was determined from the first derivative of the S-shaped cumulative fluorescence curve. kp was greater for glass (7.92 x 10(-3) cm/s) than for the other materials (polypropylene, polystyrene, polyethylene and PVA; kp approximately 3.1 x 10(-3) cm/s) in plasma with cephalin without flow. A kp for heparin-PVA could not be determined since the thrombin concentration was too low to be quantified. A larger difference between polyethylene and PVA was noted with platelet-rich plasma without flow while lower values (1.0 x 10(-3) cm/s) were noted in a flow system but at a higher surface to volume ratio. The first-order rate constant can be used in simple models relating production of thrombin at a wall of a tube to its mass transfer away from the wall in flowing blood. One such model predicts that the concentration of thrombin at the wall should become infinite at the point in the tube when the mass transfer coefficient equals kp. According to this model, kp on the order of 10(-4) cm/s would be a useful target for a nonthrombogenic material.

Amino Acid Sequence↗