bluuebunny/crossref_metadata_2025 huggingface dataset:
Acetyisalicylic Acid (ASA) does not Prolong Bleeding Time in Rats
Authors: Stella L. , Donati M. B. , Gaetano G. de
Published: June 2019

We have recently suggested (Thrombos. Diathes. haemorrh., 32, 242, 1974; Thrombos. Res., 1975, in press) that the role of platelets in the primary haeomostasis of rats may be questioned. Further evidence to this hypothesis is given by this study. Indeed, we have observed that ASA does not prolong the bleeding time in rats, whereas it inhibits in vitro collagen- or Thrombofax-induced aggregation of platelets obtained from the same animals after administration of the drug. Conscious Charles River rats, weighing 350 g., were used. Aspirin (Bayer) or lysine-acetylsalicylate (Flectadol, Maggioni) were given either per os or intrapertioneally at a dose of 200 mg/kg b.w. The effect on the bleeding time was measured 1 hour after the administration of the drug by 2 different techniques: either transecting the tip of the tails of paired animals or making 2 incisions on the tail of the same animal by an automatic, standardized template-like device (kindly provided by Prof. C. Praga, Milano). Preliminary experiments in control animals had shown no difference between the first and the second incision. The results are reported in the table.

As can be seen, ASA not only did not prolong bleeding time, but markedly shortened it. The latter result was unexpected and we have no satisfactory explanation for ist.

(Supported by Grant N. 73.00400.04 of the Italian Research Council (C. N. R.).)
“Different” Forms of Urokinase
Authors: Vukovich Th. , Binder B. , Auerswald W.
Published: June 2019

The isoelectric inhomogeneity of human urokinase (UK) derived from urine and commercial preparations have been reported. The different isoelectric forms of UKs were in part related to different mol. wts. : UKs with pis between 10.2 and 6.3 had a mol. wt. of 31.500 and UKs with pis below 5.2 had mol. wts. greater than 100,000; a UK with a mol. wt. 54,700 was not f und after isoelectric focusing.

In the present experiments we used purified UK containing only the S1-type UK – confirmed by us – as well as UK concentrated by ultrafiltration of native human urine containing all known UK-types and high mol. wt. aggregates. With short focusing times, e.g. 10 hours at 1200 V and a final 1 mA, UK activity was found only at a pi of 10.2; with extended focusing times e.g. up to 72 hours, such activity was additionally found at lower but defined pis of 8.0, 7.5, 6.9, and 6.3. All active fractions with defined pis lower than 10.2, when rerun immediately, focused at the initially determined pi values while the 10.2 fraction separated again into all the previously given lower pi fractions. The mol. wt. of all the UKs from pi 10.2 to 6.3 determined directly following isoelectric fractionation was ca. 31,500 (Sephadex G-150) while after storage for at least 1 month at 4° C at neutral pH, all the fractions contained active material of a mol. wt. less than 10,000. By focusing this low mol. wt. material UK activity could be detected only at a pi lower than 4.0.

Samples of our starting UK-containing materials were dialysed at 4° C against various buffer solutions (molarity 0.01–0.15, pH = 3.0–10.0). At pH values higher than 9.0 independent of molarity UK activities appeared in the dialysate. Isoelectric focusing of that material revealed its pi to be lower than 4.0.

(Supp. by a Grant of the Austr. Fund f.t. Promot. of Scient. Res. (Proj. Nr. 1800).)
Release of Plasminogen Activators from Isolated Human Glomeruli
Authors: Åstedt B.
Published: June 2019

Tissue culture studies have demonstrated that urokinase is produced by the kidney, but the actual site of this production is still debatable. – By passing fetal as well as mature kidneys through strains of various mesh size, combined with microdissection, isolated glomeruli were obtained. These glomeruli were fibrinolytically inactive when examined with the fibrin slide technique. On organ culture of such glomeruli on Millipore strips in a test system with a preformed plasminogen contaminated fibrin clot there occurred a marked release of fibrinolytic activators as measured by the accumulating fibrin degradation products in the culture medium. After culturehistochemical examination showed the glomeruli to be fibrinolytically active. — This suggests that the glomeruli contain inactive “preurokinase” which on active secretion is converted to active urokinase. This also means that the fibrinolytic defense system of the draining pathways begins already at the epithelial surface of the glomeruli.
Fibrin Plate Studies of Plasminogen Activator and Inhibitor from Pig Leucocytes
Authors: Stegnar M. , Kopitar M. , Accetto B. , Lebez D.
Published: June 2019

A neutral proteinase isolated from pig leucocytes by DEAE-chromatography, gel filtration on Sephadex G-100 and CM-cellulose chromatography was tested on Astrup’s fibrin plates prepared with and without plasminogen. In this way its activity of plasminogen activator was determined. The inhibitory effect of EACA, AMCHA, PAMBA and Trasylol on the activator was tested with the same method. EACA in concentration 10−2 M and 20 KIE/ml of Trasylol 100% inhibited the activator. 10−2 M AMCHA inhibited the activator by 30% in contrast to PAMBA where 70% inhibition was obtained already in concentration of 10−3 M.

With the aid of CM-cellulose chromatography and gel filtration on Sephadex G-100 two inhibitors were isolated from leucocyte cytoplasmic fraction (post granular supernatant). The inhibitory effect of the main inhibitor was determined on fibrin plates with granular extract as test enzyme, having neutral proteinase activity. The extent of inhibition of granule extract depended on the concentration of inhibitor added. Complete inhibition was achieved in the ratio 2 volumes of granule extract: 1 volume of inhibitor, protein content of the former being 800–1200 γ N2/ml and the latter 360 γ N2/ml.
Fibrin(ogen) Breakdown Products Compared in Mothers and their Newborn Infants
Authors: Graubner F. , Kleine B. , Beller F. K.
Published: June 2019

The results of fibrin(ogen)-breakdown-products (FDP) during delivery and newborns are inconclusive and dependent on the technique used. The present study was performed by using the TRCHII (Merskey, CI., Kleiner, G. J. and Johnson, Blood 17, 1, 1966). The concentration was less than 2.5 μg fibrinogen equivalents/ml serum before and after delivery and in the cord blood of the term infant. There was no difference in women who received epidural anaesthesia on oxytocin induction. In contrast FDP increased during an induction with prostaglandins in mothers and their newborn babies. The concentration of FDP was also increased in prematures and in asphyctic babies. Twin gestation revealed and increased in the mother but not in the cord blood of the twins.
The Prolonging Effect of Soy Bean Trypsin Inhibitor on the Thrombin Clotting Time
Authors: Kierulf P. , Arnesen H. , Gravem K.
Published: June 2019

Urokinase-induced fibrinogenolysis was monitored with thrombin clotting time, and inhibited by adding Soy Bean Trypsin Inhibitor (STI) (Sigma Chem. Co., U.S.A.). Depending on the concentration of STI (dialysed or non-dialysed) the thrombin clotting time was always immediately prolonged upon the addition of STI. At a concentration of 0.2–0.5 mg/ml (final conc.) no progressive prolongation of the thrombin clotting time occurred, indicating inhibited fibrinogenolysis.

By monitoring a mixture of purified human fibrinogen, thrombin and various amounts of STI, with quantitative N-terminal analysis, the thrombin clotting time prolonging effect of STI was further examined. N-terminal glycine increase, reflecting fibrin formation rate by thrombin, was unaffected by STI, whereas visible gelation occurred more slowly in the presence of STI.

Thus, STI (or a non-dialysable contaminant) acts as a fibrin polymerization inhibitor, and not as an anti-thrombin, even at concentrations regularly used to inhibit fibrinogenolysis in plasma.
The Anti-Thrombotic Effect of Warfarin, Dipyridamole and Aspirin in the Rat
Authors: Lavelle S. M. , MacIomhair Maura
Published: June 2019

Groups of rats were injected with warfarin in dosage necessary to reduce factor II to the selected range. They were then injected with dipyridamole (14 mgm/kg) and aspirin (14 mgm/kg). One group received no warfarin.

At 2 hours and 6 hours afterwards a pair and an untreated control were anaesthetised and a sterile platinum wire (0.5 × 20 min.) was inserted in the inferior vena cava for 30 minutes. The thrombus adherent to the wire was fixed with gluteraldehyde and weighed, after a blood sample had been taken for assay of factor II.

Dipyridamole and aspirin reduced thrombus weight by 40%. This effect was enhanced by factor II levels of less than 50% induced by wafarin.
Bovine Hageman Factor: Physicochemical Properties and Mechanism of Activation
Authors: Molla A. , Claeys H. , Collen D.
Published: June 2019

Bovine Hageman factor (factor XII) was obtained in inactive form from fresh plasma with a recovery of 54.7±9.0 per cent and a yield of 16.3±2.9 mg per liter. The specific activity after activation with kaolin, determined with Hageman factor deficient human plasma, was 35.6±2.6 units (the activity of 1 ml fresh BaSO4-adsorbed bovine plasma) per mg protein.

Analytical ultracentrifugation revealed a homogeneous protein with a sedimentation coefficient of 4.36. The extinction coefficient (A280 nm
%) was 14.4, and the NH2-terminal residue Ala (0.6 mole/mole determined as Dns-Ala). SDS-polyacrylamide gel electrophoresis (PAGE) in the presence of dithiothreitol revealed a doublet with an average estimated mol wt of 76,000 and a difference of less than 5,000 between the two forms. Chemical analysis revealed (in moles per mole) Met: 2; His: 59; Lys: 28; Arg: 32 and sialic acid: 13 (thio-barbituric acid assay), hexose: 26 (orcinol method). PAGE at pH 2.5 revealed two and PAGE at pH 8.3 six main bands.

Over 90 per cent of the purified iodine-labeled protein was adsorbed on celite. About 95 per cent of the enzyme activity was destroyed by incubation with 10−2 M di-iso-propylfluorophosphate (DFP) for 24 hr at room temperature. Between 65 and 85 per cent of the protein was eluted from the celite with 5% SDS. Both the NH2-terminal residue and the mol wt of the eluted protein were unchanged suggesting that activation of the proenzyme is the result of conformational changes with exposure of an active center serine residue. Measurements of radioactive DFP incorporation and COOH-terminal analysis, to prove this hypothesis are in progress.
The Evaluation of Hypercoagulability and Dic by Quantitative gel Filtration and by Chain Analysis of Isolated Soluble Fibrin Monomer Complexes (SFMC)
Authors: Graeff H. , Hugo R. von , Hafter R.
Published: June 2019

Blood samples from 89 healthy primi- and multipara during gestation were examined. Patients with septic abortion, abruptio placentae and intrauterine fetal death were also investigated. SFMC and fibrinogen were precipitated from plasma with β-alanine. Agarose gel filtration of the redissolved precipitate resulted in a separation of SFMC and fibrinogen. This enabled an estimation of the SFMC concentration (with-in assay presision: coefficient of variation = 8 per cent). The per cent amount of SFMC of the total fibrinogen content increased from 2.6±0.4 to 4.9±1.3 per cent (mean±SD) til week 40 of pregnancy. During delivery an additional increase occurred (P < 0.01). The average post partum values were 6.3±1.2 per cent. SDS-polyacrylamide gel electrophoresis of SFMC was performed before and after reduction with mercaptoethanol. The amount of α-chains was frequently found to be diminuished in assocation with faster moving components, γ-γ dimers, indicating intermolecular covalent bonding, could only be demonstrated in pronounced cases of DIC. These findings indicate that hypercoagulability and DIC may be evaluated and differentiated by the procedure described.

(Supported by DFG, SFG 51, grant no. 2/Gra – B/6.)
Disseminated Intravascular Coagulation During Severe Diseases in 0–12 Months old Children (Study on 54 Cases)
Authors: Coeugniet E.
Published: June 2019

Disseminated intravascular coagulation (DIC) occured during severe infections with: gram-negative bacteria (24 cases), gram-positive bacteria (3 cases), acute hemolysis (11 cases), pneumonias with hypoxic syndrome (16 cases). Adjuvant factors: Hypo-volaemia and metabolic acidosis (34 cases), malnutrition and hypoproteinaemia (32 cases). 38 patients were boys. Early clinical symptoms: alteration of the general state, impossibility of blood collectings because of hypercoagulability, bleeding after injections, haematemesis, melena, purpura, renal failure. Rapid laboratory diagnosis: ethanol test, paracoagulation with protamine sulphate, decrease of thrombocytes number, thrombin clotting time. The most important differential diagnosis is hypoprothrombinaenra by vit. K deficiency or by liver failure which could also complicate DIC (6 cases). During “critical” periods of diseases usually complicated by DIC the DIC prophylaxis is proposed (heparin 100–200 i.u./kg/day i.v. + dipyridamole 5 mg/kg/day i.v. or orally. The treatment of DIC: heparin 1000 i.u./kg/day i.v. or, in order to decrease the risk of secondary bleedings because of heparin an association: heparin 400 i.u./kg day i.v. + dipyridamole 5—10 mg/kg/day i.v. or orally.
Fibrinolytic and F. VIII Response to Various Stimuli in Occlusive Arterial Diasease
Authors: Ponari O. , Civardi E. , Potì R. , Dettori A. G.
Published: June 2019

The responsiveness of fibrinolytic activity and of plasma Factor VIII level to both venous occlusion (v.o.) and i.v. nicotinic acid (N. A.) was investigated in a group of patients with occlusive arterial disease.

A marked hyperfibrinolysis, with average decrease of ELT of -55%, was seen after v.o. in such patients, with a rise of F. VIII (average value +30%). A control group of comparable age but with no signs of atherosclerosis, showed similar changes after v.o. (ELT about —65% and F. VIII +60%). A comparable hyperfibrinolytic response was also found in a group of young ( < 40 y.) normal subjects.

I.V. administration of N. A. (100 mg) obtained variations of ELT of similar magnitude (—50%) in both groups (patients and age-matched controls). Changes in F. VIII were absent or only moderate.

The responsiveness to v.o. in single cases showed no correlation with an index derived from main risk factors (both clinical and biochemical) for thrombosis.

Our results do not agree with the hypotesis that an altered responsiveness of vascular fibrinolytic system is an important factor in the pathogenesis of occlusive arterial disease.
Antithrombotic Therapy 1975
Authors: Wright I. S.
Published: June 2019

It is nearly 40 years since the anticoagulant heparin was first used successfully in the treatment of thromboembolic disease. It is now appropriate to survey the enormous literature and clinical experience in an effort ot determine what effects antithrombotic therapy has had in the wide variety of conditions for which it has been used.

This presentation will consist of an analysis ot determine where we are in this rapidly evolving field and to suggest directions for further study. It will include the status of heparin including mini-heparin, the coumarin derivatives, anti-platelet aggregating substances and thrombolytic agents.

The indications for each will be listed and the unanswered questions will be stressed. The problems relating to standardization for the control of these types of therapy and the interaction with other drugs will be emphasized.
ICSH-ISTH International Anticoagulant Control Study. II. Design and Findings
Authors: Hills M.
Published: June 2019

The design and findings of the international study described in the previous Abstract will be presented with special reference to:

1. The relative sensitivity to the coumarin-induced defect of each of the 10 thromboplastins studied, from comparative tests on fresh plasma samples from treated patients.

2. Comparison of the three series of lyophylized plasmas with each other and with fresh plasmas from treated patients in assessing the sensitivity of different thromboplastins.

3. Laboratory reproducibility of prothrombin times

a) for each lyophylized plasma tested with the same thromboplastin

b) for each thromboplastin tested on the same lyophylized plasma.

4. Stability at the bench, after reconstitution, through a working day, of the 10 thromboplastins and the three lyophylized plasma series.
The Relationship between Antithrombin III, Progressive Antithrombin Activity and Anti Xa Activity in Plasma
Authors: Whigham Katherine , Howie P. W. , Forbes C. D. , Prentice C. R. M.
Published: June 2019

In 30 normal subjects, progressive antithrombin activity, as measured by the rate of thrombin neutralisation in ancrod-defibrinated plasma, was compared with antithrombin III, as measured by radial immunodiffusion. No significant correlation was found between the two methods of antithrombin measurement (r = —0.101). Similarly, no correlation was found between progressive antithrombin activity and immunological measurements of α2 macroglobulin and α1 antitrypsin. These results were not changed by using thrombin purified by Amberlite 1RC50 chromatography in place of commercial thrombin in the clotting test. There was, however, a strong positive correlation between the measurements of progressive antithrombin activity using the commercial and purified forms of thrombin (r = 0.78, p < 0.001). In contrast, there was a positive correlation between antithrombin III and anti-factor Xa activity in plasma (r = 0.48, p < 0.01). There was no correlation between plasma anti Xa activity and α2 macroglobulin or α1 antitrypsin.

These results suggest that plasma antithrombin activity is a measure of the activities of several plasma proteins and that antithrombin III may not be the major determinant of antithrombin activity. There is little evidence that immunological assays of antithrombin III reflect total thrombin inhibitory capacity as measured by the biological assay. Caution must be exercised in extrapolating from immunological measurements of antithrombin III to antithrombin activity in-vivo.
Effect of Heparin on Antithrombin III Activity During Delivery and Early Puerperium
Authors: Rákóczi I. , Garadnay B. , Arnold L. , Gáti I.
Published: June 2019

It is known that antithrombin III (AT III) is the main inhibitor of blood coagulation. It inactivates thrombin and activated × factor. Heparin increases the AT III activity in vitro as well as in vivo. The authors have studied the AT III activity in sera of 30 pregnant women, at term, before labour started (2–24 hrs) and 30 as well as 60 min after the birth of placenta and daily for five days after delivery. The AT III activity was determined using the modified method of Gerendas. Out of the 30 women 15 were given 5000 IU heparin subcutaneously 1½—2 hours before delivery. In the 15 women with no heparin treatment AT III activity of serum significantly decreased after birth of placenta compared with the predelivery value and became normal on the fifth postpartum day. Heparin given subcutaneously prevented development of this decrease.
The Effect of Sulphinpyrazone (Anturan®) on Immunologically Derived Thrombocytopenia and on Platelet Survival
Authors: White A. M. , Butler K. D.
Published: June 2019

Thrombocytopenia was produced in rabbits by means of the Arthus reaction. Animals were challenged by intradermal administration of ovalbumin (1 mg or 10 μg) on each of six sites in the back, six weeks after the first immunisation (1.0 mg alum precipitated ovalbumin) and four weeks after a subcutaneous boost (0.5 mg). Fifteen minutes after the 1 mg and 10 μg challenges there was an 83% and 26% fall, respectively, in the platelet count. This was confirmed by measurements of radioactivity in whole blood from animals which had received 51Cr-labelled platelets. Sulphinpyrazone (50, 30, 10 mg/kg) administered 1 hour before the 10 μg antigen challenge inhibited the immediate thrombocytopenia completely. Significant, but only partial inhibition was achieved with 50 mg/kg given before the 1 mg challenge. Platelet survival in rabbits was also shown to be significantly lengthened when sulphinpyrazone treatment (50 mg/kg/day) was commenced on the same day as the animals received 51Cr-labelled platelets. Both these results suggest that sulphinpyrazone can act rapidly on platelets in vivo.
Observations on Monomolecular Layers of Fibrinogen at Solid-Liquid Interphases
Authors: Cuypers P. A. , Hemker H. C.
Published: June 2019

The adsorption of fibrinogen on different surfaces was measured with the aid of an automated ellipsometer. This instrument allows measuring of both thickness and refractive index of layers between 1 and 1000 Å at 3 second intervals.

On hydrophilic surfaces a loosely packed layer of up to 130 Å grows. The refraction index is 1.4 which is the value found in the literature for hydrated proteins. The fibrinogen readily reacts with a specific antibody. No other proteins adsorb onto this layer.

On hydrophobic surfaces a layer deposits that is much more closely packed (n = 1.5; thickness 70 Å). In the course of 0.5-1 hour this layer rearranges to a still denser structure (n = 1.8; d = 35 Å). These dense structures too react with specific antibodies but no other proteins will be adsorbed.

The structure of the γ-globulin layer is dependent on the structure of the underlying fibrinogen. Fibrinogen does replace adsorbed layers of other proteins. These observations can be used as the basis for the screening of surfaces for their antithrombotic properties.
Interaction of Platelets with Model Surfaces III: Platelet Reaction with Synthetic Polymers
Authors: Lindon J. N. , Brier D. , Merrill E. W. , Salzman E. W.
Published: June 2019

Blood/material surface interactions have been studied by passing citrated whole blood over beads in a column and examining the resultant activation of platelets and coagulation factors. Examination of many polymer and some crystalline surfaces indicates that platelet adhesion occurs with all surfaces except after pretreatment with albumin in some instances. Induction of the platelet release reaction and platelet adhesion vary from one surface to another and are not well correlated. The release reaction in response to some but not all surfaces can be blocked by pretreatment of blood with aspirin in vivo and indomethacin in vitro. PRP exhibits less activation than whole blood, but varying the hematocrit of whole blood from 23 to 53% does not change surface reactivity.

Of the materials studied, polyethylacrylate (PEA) and polymethylacrylate (PMA) appear least reactive. Certain materials, e.g. polystyrene and polyvinylacetate, exhibit variable surface reactivity with different blood samples, while others, e.g. pyrolytic carbon and PMA, produce a uniform response. A general trend appears to be less surface reactivity with decreasing glass transition temperature. Chemical modification of polymers and production of copolymers has been undertaken to define the nature of reactive sites. For example, acrylonitrile and aminomethylacrylate copolymers of PMA exhibit more reactivity than PMA.

Sepharose 4B (4% agarose gel beads) appears essentially non-reactive. However, Sepharose with covalently bound heparin promotes extensive platelet adhesion. Pretreatment of this surface with increasing amounts of plasma, but not albumin, produces decreasing surface reactivity.
Decreased Platelet Adhesion as a Characteristic of Non-Thrombogenic Heparinized Polymer Surfaces
Authors: Lagergren H. , Larsson R. , Olsson P. , Rädegran K. , Swedenborg J.
Published: June 2019

Non-thrombogenic surfaces with a stable heparin layer were made of ionically bound heparin cross-linked with glutardialdehyde.

In vivo the retention of platelets on heparin coated and untreated arterio-venous plastic shunts were compared. The retention of 51Cr labelled platelets on treated surfaces was less than 5% of that on untreated surfaces. The results were not influenced by systemic heparinisation or fibrinogen depletion.

In vitro heparinized blood was rotated in coated and nontreated tubes. The retention of platelets on treated tubings was less than 0.5% of that on non-treated tubings. The heparin concentration of blood did not influence this platelet retention.

It is concluded that the non-thrombogenic capacity of the heparinized surface is due to inhibited platelet adhesion.
The Isolation Procedure and Some Characteristics of c-AMP Dependent Protein Kinases of Human Blood Platelets
Authors: Kahlé L. H. , König B. W. , Cate J. W. ten
Published: June 2019

Several protein kinases have been isolated from human platelet which bind cyclic AMP and transfer a phosphate group from the terminal position of ATP to a protein acceptor molecule.

The purification was performed by homogenization in a 50 mM Tris MCI buffer at pH 7.0 which contained 2 M.KC1, subsequent centrifugation at 100,000 g for 1 hr., ammonium sulfate precipitation of the supernate, gel filtration over Sephadex G 25 and DEAE Sephadex chromatography with a linear gradient of 0-1 M.NaCl in Tris HCl buffer at pH 7.0. DEAE Sephadex chromatography resulted in three peaks, which contained kinase activity. Only peak II and III contained c-AMP acceptor activity, which reached an optimum at pH 5.5 in phosphate buffer.

The kinase activity was stimulated by c-AMP in all three peaks while the first peak also had some c-AMP independent kinase activity. The kinase activity was dependent on Mg ions. Difference in activity in the three peaks was observed depending on the acceptor protein that were used. Acceptor proteins studied so far were hist on and protamine. Isolation of an acceptor protein from the platelets is in progress.
The Value of Doppler Ultrasound in Patients with a Clinical Diagnosis of Deep Venous Thrombosis
Authors: Meadway J. , Nicolaides A. N.
Published: June 2019

It has been suggested that Doppler ultrasound examination is useful in the diagnosis of deep venous thrombosis (DVT). The present study was undertaken to compare ultra sound with venography in 120 limbs of 106 patients who presented with clinical DVT or pulmonary embolism. A Parks 801 ultrasonic detector was used over the femoral and popliteal veins with calf compression before and after occlusion of the long saphenous vein at the knee.

DVT was confirmed by venography in 44 limbs and was confined to the calf in 10 of these. Ultrasound detected 3 calf thromboses and 29 of 34 more extensive thromboses. The five failures with thrombus proximal to the calf were associated with partial occlusion (1) or extensive collateral circulation (4). Of the 76 limbs normal on venography 21 were thought to have DVT by ultrasound: these false positives could be attributed to oedema (11), haematoma (4), lymphocyst (1), injured muscle (1), cellulitis (1) or excessive tenderness (2) and were unexplained in 1. The results indicate that this test is more accurate than clinical signs alone, but users must be aware of its limitations, particularly the causes of false positive and false negative results.
New Techniques of Phlebography
Authors: Jamieson M. P. G. , Macintyre I. M. C. , Buist T. A. S. , Ruckley G. V.
Published: June 2019

There are clinical situations in which conventional methods of phlebography are technically difficult or unhelpful towards the management of patients with venous thrombosis. Two new phlebographic techniques have been developed for such situations.

Firstly, when patients cannot be readily transported to the Radiology Department because of skeletal traction or monitoring apparatus, a bedside technique has been devised. A central venous catheter is advanced up the long saphenous vein from the ankle, allowing examination both of the peripheral veins and the ilio-femoral segment. The catheter is left in situ for up to 48 hours to allow monitoring of thrombolytic therapy by serial films. This method has been employed in 12 patients. Where, because of extensive occlusion, conventional phlebography fails to outline the proximal extent of the thrombus and where the contralateral ilio-femoral segment is patent, a cross-over technique has been developed. This method is also indicated where percutaneous femoral phlebography cannot be performed because of local sepsis, proximity to an operation site or when the limb is encased in plaster of Paris. Under fluoroscopic control a flexible catheter is passed to the vena cava and down the contralateral iliac veins. This method has been used successfully in 25 patients. No complications have been experienced with either technique.
Electron Microscope Analysis of the Surface Charge of Human Platelets; Stored and Aggregated by Polymeric Bases
Authors: Taketomi Y. , Ihara A. , Kuramoto A. , Uchino H.
Published: June 2019

The stainability of the surface coat of human platelets with positively charged colloidal Thorotrast was studied on the stored and aggregated platelets by some aggregating agents. During storage, the total sialic acid decreased and fell to 65% of initial value on 5th day. The sialic acid released from fresh platelets by neuraminidase treatment was 80% of the total. The density of Thorotrast particles on surface coat did not change during storage up to 7 days. These particles were abolished to some extent from the surface of neuraminidase treated platelets. These particle density did not change significantly in ADP and collagen induced aggregates but decreased in aggregates induced by cationic polymers such as protamine sulfate and polylysine. At the same concentration of polylysines of different degree of polymerization, maximal aggregation was greater with the higher molecular weight. Average distance between the plasma membranes of two adjacent cells in the aggregate was rather wider when the higher molecular weight polylysine was used.
Thrombolytic Therapy of Deep Venous Thromboses with Urokinase
Authors: Theiss W. , Kriessmann A. , Wirtzfeld A.
Published: June 2019

The minimal effective dose of urokinase for long-term thrombolytic therapy - as required for venous thromboses - is of particular interest because of the limited availability and high cost of urokinase. This fibrinolytic agent was used by us in 4 patients suffering from deep venous thromboses : in 2 of them immediately after a 5 day course with streptokinase had yielded unsatisfactory results, and in the other 2 because of high titers of anti-streptokinase due to prior therapy with streptokinase. Urokinase was administered as a continuous infusion for periods of 5 to 10 days at a dose of 10,000 or 20,000 Ploug units/ hour. At neither dosage any of the customary drastic changes of laboratory parameters observed during streptokinase therapy were found: fibrinogen and plasminogen remained within the normal range, FDP levels were increased moderately and inconsistently only, while euglobulin lysis times were shortened markedly at times and minimally only at others. Without evident correlation to these laboratory parameters, subsequent Phlebographic controls revealed excellent results in 2 of the patients, while partial success was achieved in the other 2. So it appears that an effective thrombolytic state can be achieved with urokinase at comparatively low dosages with little degradation of circulating fibrinogen. This difference to streptokinase may be explained by the action of urokinase as a direct activator and by its alledged higher specific fibrinolytic activity as compared to its fibrinogenolytic activity.
Fibrinolytic Therapy in Central Retinal Vein Occlusion
Authors: Pettit J. E. , Kohner E. M. , Bulpit G. J. , Hamilton A. M.
Published: June 2019

A controlled clinical trial was conducted on patients with central retinal vein occlusion who presented within seven days of their initial symptom and in whom there was no contraindication to fibrinolytic therapy. There were 20 treated and 20 control patients between 1970 and 1974.

Treatment comprised 72 hours full-dose streptokinase (SK) therapy followed by 48 hours heparin and six months warfarin therapy. Progress was monitored for one year by periodic ophthalmological examinations, including colour and fluorescent photography.

The final visual acuity was similar in both groups of patients. Vitreal haemorrhage occurred in three patients receiving SK and these patients remained blind. Two control group patients had vitreal haemorrhage from new blood vessels six months after presenting. Four control patients developed thrombotic glaucoma; this painful end result was not observed in SK treated patients.
Disseminated Intravascular Coagulation (DIC) and Toxaemia of Pregnancy in Kuwait
Authors: Youssef A. H.
Published: June 2019

43 patients with pre-eclampsia and 9 patients with eclampsia were studied and compared with 57 normal pregnant women and 36 healthy non pregnant women.

Functional tests of Disseminated Intravascular Coagulation (DIC) were carried out on patients and controls. These tests included platelet count, plasma anti-heparin activity, serum FDPs and plasma fibrinogen levels, euglobulin plasma clot lysis time, thrombin, prothrombin and Kaolin-cephalin times. The results of the tests are presented and confirmed that DIC occurs in toxemia of pregnancy.

Patients with pre-eclampsia and eclampsia had low platelet counts with high plasma anti-heparin activity, low plasma fibrinogen levels, raised serum FDPs concentrations and prolonged thrombin and euglobulin lysis times. These findings indicate that toxemia of pregnancy can be attributed to DIC.
An Abnormal Fibrinogen in a Venezuelan Family
Authors: Bosch N. B. , Arocha-Piñango G.
Published: June 2019

An apparently new fibrinogen abnormality, inherited as an autosomal dominant trait, was found in 4 members of a family affected with moderate bleeding. Prolongation of plasma prothrombin, thrombin and Reptilase times and normal concentration of fibrinogen were observed. Normal values of platelet aggregation, FDP and antithrombin III levels were obtained. The k value of the thromboelastogram was slightly increased. Factor XIII was 50 to 60% (Beringwerke F XIII kit) and 100% by radial inmuno diffusion. Photometric study of thrombin induced polymerization of fibrin in plasma or purified fibrinogen and the aggregation of monomers in plasma measured by a two stage method, were abnormal. Marked prolongation of the clotting time of fibrin monomers were observed at pH over 7.4. Alterations of polymerization curves and plasma thrombin time were accentuated by raising molarity and ameliorated by Ca ions, increasing thrombin concentration and frozen storage. Normal plasma was slightly inhibited by patient’s plasma in these tests.

Normal electrophoretic mobility of the abnormal fibrinogen was shown on cellulose acetate, Polyacrylamide and inmunoelectrophoresis. Ouchterlony inmunodiffusion revealed non-identity pattern with normal fibrinogen.
Thrombin and Reptilase Induced Fibrin Structures in the Presence of Dextran: A Quantitative Electron Microscope Study
Authors: Krause W. H. , Zimmermann P.
Published: June 2019

The present study describes an electron microscopic analysis, using a quantitative morphometric method, of fibrin network obtained by thrombin and reptilase in the presence of dextran. The thickness of the thrombin induced fibrin meshwork show a significant difference compared to fibrin formed by reptilase. The segment length of reptilase fibrin are reduced to 25% and the thickness of the fibers are reduced to 75% in comparison with thrombin fibrin.

The thickness of the fibrin meshwork obtained by thrombin and/or reptilase in the presence of dextran (

w 40,000) is significantly diminished compared to saline controls (p < 0.001). Segment length and thickness of fibers in the clots with dextran showed different results when thrombin or reptilase were used as enzyme.

The investigation indicates that the fibrin meshwork formed by thrombin and/or reptilase in the presence or absence of dextran result in a significantly different fibrin morphylogy. The results are different to the so far descriptive electron microscopic studies.
Inhibition of Human Platelet Aggregation by the Proteolytic Effect of Streptokinase (SK). Role of the Factor VIII Related Antigen
Authors: Castillo R. , Maragall S. , Guisasola J. A. , Casals F. , Ruiz C. , Ordinas A.
Published: June 2019

Defective ADP-induced platelet aggregation has been observed in patients treated with streptokinase. This same effect appears “in vitro” when adding SK to platelet rich plasma (PRP). Classic hemophilia and normal platelet poor plasmas (PPP) treated with SK inhibit the aggregation of washed platelets; plasmin-treated normal human serum also shows an inhibitory effect on platelet aggregation. However, von Willebrand SK-treated plasmas do not inhibit the aggregation of washed platelets. The same results appear when plasmas are previously treated with a rabbit antibody to human factor VIII.

This confirms that the antiaggregating effect is mainly linked to the digested factor VIII related antigen.

The inhibition of ADP-induced platelet aggregation has been proved in gel filtration-isolated and washed platelets from SK-treated PRP.

Defective ristocetin-induced platelet aggregation has also been observed- This action does not appear in washed platelets from SK-treated PRP in presence of normal PPP, but it does in presence of SK-treated PPP, which suggests that the inhibition of the ristocetin-induced aggregation is due to the lack of factor VIII and not to the factor VIII-related products.

Heparin, either “in vivo” or “in vitro”, has corrected the antiaggregating effect of SK.
Duration of the Inhibition Effect of Acetylsalicylic Acid on Human Platelet Function
Authors: Baele G. , Verdonck L. , Vermeulen A. , Barbier F.
Published: June 2019

Six useful parameters of the release reaction are measured in 10 human volunteers prior to Aspirin® intake and 1,4,5,6 and 7 days after a single ingestion of 1 gram Aspirin®. These parameters include the intensity of aggregation after 5 min by diluted collagen (ΔE5) and after 10 min by Thrombofax® (ΔE10) and the serotonin-14C release by undiluted and diluted collagen, by Thrombofax® and by bovine plasma.

Although a significant inhibition (Wilcoxon signed rank test) is found one day after the Aspirin® ingestion, the duration of the inhibition effect is different according to the test used. The inhibition of the aggregation and serotonin-14C release by Thrombofax® is no longer present on the 4th day. The inhibition effect is found till the 4th day using the serotonin-e14C release by bovine plasma, till the 5th day using the Serotonine-14C release by undiluted collagen and till the 6th day using the aggregation intensity by diluted collagen. The duration of the inhibition is most prolonged (till the 7th day included) if serotonin-14C release by diluted collagen is measured. Individual differences in intensity and duration of the ASA effect on the platelets are noted.

In conclusion, the methods for studying the modification of the platelets by acetyl-:salicylic acid are different in sensitivity as to the duration of the inhibition effect after a single oral ingestion. A combination of different tests allows an easier detection of an ASA effect in a single patient.
Comparison of the Effects of Some Anorectic Drugs on Platelet and Brain 5-Hydroxy-Tryptamine (5 HT) in Rats
Authors: Roncaglioni C. , Buczko W. , Samanin R. , Gaetano G. de , Garattini S.
Published: June 2019

A number of anorectic drugs have been studied for their effects on the uptake and release of 5 HT in platelets and on the levels of brain 5 HT and 5-hydroxyindolacetic acid (5HIAA) in the rat. Platelet studies have been performed in vitro, whereas brain levels have been measured after drug administration. Phentermine (α-dimethylphenylethylamine), die-thylpropion (2-diethylamino propiophenone) and d-amphetamine sulphate showed no effect on the above parameters. Mazindol (5(p-chlorophenyl)-2-5-dihydro-3H-imidazo-(2-1-α)isoindol-5-01) inhibited 5HT uptake by platelets, but neither induced release of 5HT from platelets nor modified 5HT or 5HIAA levels in the brain. Both d-fenfluramine H-Cl and 4-chloroamphetamine-HCl inhibited 5HT uptake by platelets, induced release of platelet-bound 5HT and lowered brain 5HT and 5HIAA levels. S 922 (trifluoro-methylphenyl(benzoyloxy)ethylamino-2-propane), a congener of fenfluramine, was inactive as an inhibitor of 5 HT uptake, was a weak releaser of 5 HT from platelets but effectively reduced 5HT and 5HIAA levels in the brain. This drug is rapidly metabolized in vivo to form fenfluramine.

The in vivo effects of anorectic drugs on brain 5 HT levels seem therefore correlated with the capacity of these drugs to release in vitro 5 HT from platelets rather than with their in vitro inhibitory activity on platelet 5HT uptake.

Supported by Grants 1ST. 73-00400-04 and H. 73-00218-31 of the Italian Research Council (C.N.R.).
Anticoagulation During Six Hours of Extracorporeal Perfusion. Comparison between Heparinization and Defibrinogenation
Authors: Berglin E. , Hansson H.-A. , Teger-Nilsson A.-C. , William-Olsson G.
Published: June 2019

Four dogs were given heparin and four other dogs were defibrinogenated with Defibrase®. The dogs were then perfused for six hours with a membrane oxygenator. Capillary bleeding tendency was measured with a standardized skin-flap technique. Platelet accumulation in the lungs and on the oxygenator membranes was examined with 51Cr-labelled platelets and with scanning electron microscopy. Fibrin deposits on the oxygenator membranes were examined with immunoelectrophoresis after plasmic degradation. Pump flow, gas transfer across the oxygenator membrane and coagulation data were followed.

Capillary bleeding from the skin-flap was more pronounced in the dogs treated with heparin than in the defibrinogenated dogs. The 51Cr-labelled platelets accumulated in the lungs and on the membranes of both groups, but more pronounced in the heparinized animals. Scanning electron microscopy confirmed the findings for oxygenator membranes. Both groups of animals had fibrin deposits on the membranes with wide individual variations. There was no difference between the two groups concerning gas exchange across the oxygenation membranes. The pump flow was higher in the defibrinogenated dogs (mean flow 38-64 ml/min and kg bw) than in the heparinized ones (mean flow 22-40 ml/min and kg bw).

Anticoagulation with Defibrase® might be an alternative to heparin during prolonged extracorporeal perfusion.
Inhibition of Ristocetin-Induced Platelet Aggregation (RIPA) by Haemaccel® and Fibrinogen
Authors: Stibbe J. , Kirby E.
Published: June 2019

RIPA was investigated using purified human factor VIII (F VIII) and formalin-treated washed platelets suspended in tris buffered saline. At constant (F VIII), aggregation was very sensitive to the conc, of Ristocetin (R) in the range 0.2-0.5 mg/ml, but higher (R) did not further increase aggregation. At constant (R), increasing (F VIII) caused increased aggregation for any (F VIII) used (0.3-3.0 μg protein/ml, 0.015-0.15 U F Vlll-related ant ig en/ml).

RIPA was inhibited by low conc. (0.15 mg/ml) of the gelatin plasma expander Haemaccel (H) (Behringwerke). Addition of H after aggregation was complete caused reversal of the aggregation. The inhibition could be overcome by increasing (R), but not by increasing (F VIII) in the conc, ranges used. The conc, of R which overcame H inhibition also caused precipitation of H. This precipitation could be reversed by increasing (H). Our evidence suggests that H inhibits RIPA by binding R, thus inhibiting the interaction of R and F VIII on the platelet surface which is responsible for aggregation.

Human Fibrinogen (Fb) (Kabi, 99% pure, 0.5 U F Vlll-related antigen/mg) caused a similar inhibition of RIPA in conc, as low as 0.2 mg/ml. Higher conc caused greater inhibition, which could be overcome by increasing (R). The Fb (2.5 mg/ml) itself did not induce aggregation in the presence of R. R may also bind to other plasma proteins as well since it can form a precipitate with serum.

These findings are of considerable importance for the quantitative measurement of the Ristocetin co-factor. RIPA is very sensitive to a small range of (R) and the availability of R in the test system can be greatly affected by the presence of Fb and other plasma proteins.
Influence of Plasmin Inhibitors on Differentiating Digestion between Fibrinogenolysis and Fibrinolysis
Authors: Abe T. , Kazama M.
Published: June 2019

It was noted that fibrinogen as well as fibrin were digested almost at the same rate with plasmin, irrespective if it was pre-activated or natively activated in the purified reaction mixture. Fibrinogen digestion, however, was markedly inhibited compared to fibrin.digestion in normal human plasma after the addition of UK. The same differentiating digestion was observed after the addition of UK to the mixture of fibrinogen/fibrin, plasminogen and plasma fraction containing α2-macroglobulin or αrantitrypsin, while the differentiation has not occurred in the mixture of fibrinogen/fibrin and plasmin-α2-macroglobulin complex which was prepared preliminarily. It was postulated that the differentiating digestion between fibrinogen and fibrin was possible under the coexistence of native plasmin and plasmin inhibitors.
Effect of Phospholipase C on Human Platelets
Authors: Otnœss A.-B.
Published: June 2019

The effect on human platelets of phospholipase C (Bacillus cereus) has been studied. Platelets prepared by gel filtration lost 20-30% of their phospholipids when incubated with phospholipase C for 20 min. Phosphatidylethanolamine (PE) was reduced by about 50%, whereas phosphatidylcholine and phosphatidylserine were reduced each by about 20%. Sphingomyelin was not reduced.

These data suggest an asymmetrical distribution of phospholipids in the platelet membrane, PE being more accessible and therefore probably mainly located in the outer part of the membrane.

The loss of phospholipids was not accompanied by aggregation, nor did the platelets lose their ability to aggregate with thrombin or ADP. Data on release of serotonin, platelet factor 3 and 4 and scanning electron micrographs of treated platelets will be given.
Repeated Phlebographies for Follow-Up of Deep Vein Thrombi
Authors: Gruber U.F. , Hongler Th. , Jung W. , Hutter O. , Steinmann E. , Schmitt H.
Published: June 2019

In a prospective, randomised, controlled study comparing the effectiveness of minidose heparin and dextran 40 for reducing deep vein thrombosis (DVT) after major surgery, we have shown that in the control group 36% of the 107 patients so far studied develop DVT, 13% of the 105 patients in the heparin group and 20% of the 104 in the dextran group. Both heparin and dextran show a statistically significant effect. In addition we carry out repeated phlebographies in all patients developing DVT as proven by the fibrinogen test. Immediately after the diagnosis is made, a first phlebography is carried out, a second one 14 days later. Results:

Only 1 thrombus, in a heparin patient, increased in size.

It is hoped to gain further insight into the course of an established thrombus and how it is influenced by drugs as s.c. heparin and dextran by continuing this extremely time-consuming and difficult study, since it is not easy to carry out repeated phlebographies in the same patient.