bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Patient with Acquired von Willebrand’s Syndrome and Platelet Aggregating Activity in the IgC Fraction
Authors: ten Cate J. W. , Wanders R. , Schneider-Trip M. 
Published: June 2019

A new case is described of acquired von Willebrand’s syndrome: bleeding time 20’; platelet-adhesion 20%; F. VIII 9% (procoag. act.); F. VIII R. A. not demonstrable; von Willebrand factor activity (Weiss assay) not demonstrable; absent Ristocetin aggregation. No anti-F. VIII activity could be demonstrated in vitro. Cryoprecipitate infusion resulted in low recovery of f. VIII activity and no f. VIII-synthesis. The serum contained a platelet aggregating activity when tested on normal PHP or washed platelets of 30 random selected donors, and also in PRP of hemophilia A or severe von Willebrand patients. The aggregating activity was present in serum, heated serum (30’ 56° C), BaSO4 absorbed serum, in the IgG fraction isolated both by column chromatography and by ultracentrifugation. Absorption of serum with Vo fraction (sepharose 6B) of normal cryoprecipitate did not remove the aggregating activity. Aggregation was not inhibited by aspirin, adenosine or heparin and was inhibited by EDTA and Cocain and independant of complement. The aggregation was characterized by serotonin and nucleotide release in comparable amounts as thrombin. E. M. studies revealed degranulation and viscous metamorphosis.The platelet aggregating activity is probably due to platelet antibodies.
Von Willebrand Disease (vWd) Characterized by Increased Ristocetin Aggregation: A Study of Eleven Cases
Authors: Ciavarella N. , Pareti F. I. , Ruggeri Z. M. , Mannucci P. M. 
Published: June 2019

The defective ristocetin aggregation occurring in patients with vWd is thought to depend on the decrease of a plasmatic factor related to factor VIII (Willebrand factor, VIIIVWF) 10 patients from 3 families had a mild to moderate bleeding tendency with autosomal dominant pattern of inheritance and laboratory findings suggestive for vWd (decreased levels of antihemophilic factor, and factor- VIII related antigen reduced platelet retention to glass beads columns and prolonged bleeding time). However, ristocetin aggregation in PRP was markedly increased, although VIIIVWF plasma levels were decreased. Aggregation induced in PRP by other agents (such as ADP, adrenaline and collagen), and the release of 14C serotonin was normal; the addition of purified bovine factor VIII was followed by normal aggregation in patients’ PRP and washed platelets. Patients’ washed platelets added to normal plasma aggregated to ristocetin more than normal washed platelets with patients’ plasma; the most marked aggregation response, however, was obtained when patients’ washed platelets were mixed with their own plasma. These findings suggest that a, platelet component is involved in the hyperaggregation response to ristocetin of these patients; however, the interaction of platelets with patients’ plasma is needed to produce the maximum response.Supported by a grant of the Fondazione Angelo Bianchi Bonomi.
Clinical and Genetic Aspects in 22 Patients with Thrombasthenia
Authors: Seligsohn U. , Reichert N. , Ramot B. 
Published: June 2019

Glanzmann’s thrombasthenia has been observed in Israel relatively frequently especially among Iraqi Jews. This paper presents a countrywide survey. Twenty two patients (12 males and 10 females) fulfilled the minimal criteria for establishing the diagnosis of thrombasthenia which were: A lifelong history of a bleeding tendency, a normal platelet count, absent clot retraction and at least 2 of the following: Prolonged bleeding time, isolated platelets on a blood smear and markedly impaired ADP aggregation. The frequencies of bleeding manifestations were: Purpura 100%, monorrhagia 100%, following circumcision 100%, epistaxis and gum 86%, gastrointestinal 68%, hematuria 32% and hemarthrosis 9%. Platelet transfusions seemed beneficial in preventing excessive bleeding in 4 patients who underwent a Caeserian section, 2 circumcisions and extensive abdominal surgery, respectively.Genetic analysis was possible for 21 patients who belong to 12 unrelated kindreds: 11 Jewish (of whom 10 are Iraqi) and one Arab. Parental consanguinity was present in 9 of sibships. The corrected segregation ratio was 0.20, which is compatible with autosomal recessive inheritance. Twelve obligatory carriers were available for studies. In none of them was it possible to detect impaired platelet functions.
Platelet Factor XIII in Hyperlipidemias
Authors: Scrobohaci M. L. , Stäncioiu N. , Stejänescu N. , Idu S. 
Published: June 2019

The total platelet factor XIII–T. P. F. XIII (after destroying by triton) and the released one – R. P. F. XIII (during thrombin induced platelet aggregation) were quantificated in IIa, IIb, IV types of hyperlipemia and myeloproliferative disorders subjects compared to normal control subjects.T. P, F. XIII was increased in IIb and IV, and normal in IIa types of hyperlipemia while it was decreased in myeloproliferative disorders. R. P. F. XIII was increased only in IIb, “nul” in IIa, IV types of hyperlipemia, myeloproliferative disorders and control subjects too.Both T. P. F. and R. P. F. XIII increased values in IIb parallel the increased platelet aggregation in these subjects. On the contrary the lack of R. P. F. XIII in IIa and IV types is concordant with normal platelet aggregation revealed in our subjects too. In myeloproliferative disorders when the platelets are “pool-vide” the T, P. F. and R. P. F. XIII is much decreased. These data supported the enhance thrombogenic tendency in IIb type hyperlipemia by platelet increased activity and decreased fibrinolysis due partially to enhanced fibrin stabilization. Other factors incriminated in the decrease of fibrinolysis and increased platelet aggregation, not discussed here, may be responsible for the type IV as thrombogenic as IIb and may counter balance our disordant data in these more prevalent types. The myeloproliferative disorders data are consensual with the tendency to bleeding disorders.
Assay of Antiplatelet Antibodies in Immune Thrombocytopenic Patients by Sedimentation Pattern Test
Authors: Pogliani E. , Cofrancesco E. , Volpe A. Della , Cortellaro M. , Masera G. , Polli E. E. 
Published: June 2019

15 sera from never transfused thrombocytopenic children (idiopathic thrombocytopenic purpura, drug induced and post-viral thrombocytopenia) were performed in a microtechnique according to the modified sedimentation pattern test of Myllyla (1). Eighter percent of these sera, tested against a pannel of at least five healthy donors, gave a positive result at different dilutions (from ¼ to ⅙). This quantitative platelet agglutination assay, compared with platelet aggregometry and 14 C-serotonin release, seems to be a sensitive, simple and reliable method to detect antiplatelet antibodies. Therefore it could have clinical applicability to the study of patients affected by immune thrombocytopenia.(1) Myllyla, G.: Aggregation of human blood platelet by immune complexes in the sedimentation pattern test.Scand, J. Haemat. suppl. 19, 1973.
Serum Fibrin/ Fibrinogen Degradation Products (FDP) after Experimental Pulmonary Embolism in Dogs
Authors: Jones D. R. B. , Cash J. D. , Owens Rosemary , Dalton R. G. , Ruckley C. V. 
Published: June 2019

In previous clinical studies we reported elevated serum FDP values after pulmonary embolism. We detected high values in only 50% of patients and the elevation was transitory. In order to determine the exact time and magnitude of the FDP elevation, and whether the increase was consistent, experimental pulmonary emboli were produced in dogs.Under pentobarbitone anaesthesia emboli of autologous clot were injected via the femoral vein. FDP, platelets and fibrinogen were estimated on frequent samples taken via a jugular vein catheter. The FDP were measured by the Tanned Red Cell Haemagglutination Inhibition Immunoassay with reagents specific for dog fibrinogen.It 5 control animals FDP values rose gradually during 8-12 hours of anaesthesia. In 11 dogs receiving 3 ml/ kg of clot the mean FDP rose from 9 ug/ml at rest to 142 ug/ml (Range 9–16100 ug/ml). The peak of FDP was reached in 30-60 minutes and remained significantly above control values for up to 7 hours. These data support our view thai’FDP measurement is valuable in the diagnosis of venous thrombo-embolic disease.
Fibrinogen α-Chain Resistance to Arvin (Ancrod) in DIC
Authors: Lane R. S. , Baugh O. H. , Flude P. T. 
Published: June 2019

In high concentrations, Arvin (Ancrod) splits fibrinogen α-chains into fragments of 39,000 and 31,000 molecular weight. In a patient with mild chronic DIC, secondary to a dissecting aneurysm, plasma fibrinogen exhibited marked resistance to normal α-chain proteolysis by Arvin. The patient showed a moderate haemostatic defect acquired from the time of aortic dissection: bleeding was stopped with EACA. Tests were consistent with the presence in plasma of high and low molecular weight FDP, thus deficient haemostasis could be explained by defective fibrin polymerization and X-linking.The α-chain resistance to Arvin was a coincidental finding. Does this behaviour represent a defect and, if so, is it congenital, or acquired representing a previously unencountered phenomenon associated with DIG? The data show Arvin to be a valuable agent for the rapid isolation and investigation of fibrinogen in normal and pathological plasmas.
Intravascular Acoustic Microstreaming as an Initiator of Mural Thrombi in Vivo
Authors: Williams A. R. 
Published: June 2019

Acoustic microstreaming (a rapidly rotating small-scale eddy of blood) is developed inside blood vessels when a discrete portion of the vessel wall is driven to oscillate at an ultrasonic frequency. The wall of the intact vessel was set into motion by the external application of a steel probe (a 115 μm radius wire oscillating transversely at 20 kHz or the 52.5 μm diameter tip of an exponentially tapered velocity transformer oscillating in its longitudinal mode at 80 kHz). The intravascular microstreaming field subjects the vascular endothelium immediately adjacent to the probe tip to large hydrodynamic shear stresses which renders that surface thrombogenic. Simultaneously, platelets are traumatized by the same microstreaming field and are bomarded against the vessel wall where they appear to participate in the formation of mural thrombi. Small blood vessels are completely occluded by platelet plugs which may be stabilized by the formation of fibrin.This technique produces discrete localized intravascular thrombi by the non-invasive application of hydrodynamic shear stress in the absence of any other thermal, chemical or electrical trauma. It therefore provides a novel in vivo model to investigate the effect of biological and pharmacological variables on thrombus growth and development, and the nature of the repair processes.
Phospholipase A2 and Competitive Inhibition of Procoagulant Phospholipids
Authors: Boffa M. C. , Boffa G. A. 
Published: June 2019

A protein with anticoagulant and phospholipase Aa activities was isolated by chromatography, from Vipera berus venom. The phospholipase activity was demonstrated on isolated platelet phospholipids and derivatives were analysed on thin layer chromatography. The strong anticoagulant activity on recalcified platelet poor plasma, is not dependent upon any proteolytic effect. It is due to a competitive inhibition of the phospholipid procoagulant activity. The inhibition constant has been determined.The same molecule appeared to be responsible for both activities as demonstrated by continuous gradient chromatography, polyacrylamide gel electrophoresis and electro-focusing.Inactivation studies permitted to consider that each of both activities was related to a different site on the same molecule.
Complex Role of Fibrinogen A α-Chain in Fibrin Crosslinking and Gel Formation
Authors: McDonagh R. P. , McDonagh Jan , Shen L. L. , Hermans J. 
Published: June 2019

The Aα-chain of fibrinogen has several important functions. Its NH2-terminus is the primary proteolytic site for thrombin and most coagulant enzymes. The fragile COOH-terminus, highly susceptible to plasmin proteolysis, renders fibrinogen heterogeneous in plasma. Another important role of the COOH-terminal region is in providing the primary sites of crosslinking of the α-chains of fibrin by factor XIHa, which makes the covalently crosslinked network resistant to proteolysis and increases the elastic modulus of the gel. Degradation of isolated α-polymer and α-chain monomer with cyanogen bromide (CNBr) lias revealed α- single peptide of molecular weight 2,400 which is involved in crosslinking. A core CNBr fragment of approximate m.w. 30,000 is not involved. No other peptide fragments have been detected which participate in α-chain crosslinking. Treatment of fibrinogen at low concentrations with thrombin and small amounts of plasmin results in gels which transiently develop much higher elasticity than in the absence of plasmin. Fibrinogenolysis proceeds to first give proteolysis near the CCOH-termmus of Aα-chains. Assuming that this is true also of fibrinolysis, we see that either splitting of a peptide bond near the COOH-terminus of α-chain or formation of additional isopeptide bonds in this region, may strengthen the structure of fibrin gel.Supported by Grants HL 14228 and HL 06350 from the National Institutes of Health, U.S.A.
Inaccurancies of Clotting Tests in Early Diagnosis of Post-Operative Deep Vein Thrombosis (D. V. T.)
Authors: Plante J. , Boneu B. , Gaillard J. 
Published: June 2019

Two groups of pneumonectomized patients with diagnosis of pulmonary carcimona were successively studied to assess the diagnostic and predictive values of some clotting test in post-operative D. V. T. The incidence of D. V. T. was determined by the 125I fibrinogen method. Simultaneously blood clotting tests including thromboelastography (T.E.G.), P.T.T. platelet count, fibrinogen level, F. D. P. assay, ethanol test were performed both before and after the surgical procedure on the 2d, 4th, a.nd 7th post-operative days. The first group (32 patients) received subcutaneous Heparin beginning on the third post-operative day. The dose (5000 to 10000 u T. I. D.) was adapted according to the results of the T. E. G. in an efford to obtain an isocoagulable state. The second group (45 patients) received 5000 u of heparin subcutaneously (B. I. D.) with the first injection two hours before the surgical procedure: the dose was adapted on the third day according to the T. E. G.The results of this study show: (1) The frequency of blood clotting disturbances is similar in both groups in spite of pre-operative heparinotherapy. (2) The first group presented five D. V. T. and two fatal pulmonary embolisms whereas the second group presented only three D. V. T. (P < 0,1). (3) There is no correlation between a positive scanning of the lower limbs and blood clotting disturbances.In conclusion, clotting disturbances seem to be related to either to surgical procedure or to the carcimona. D. V. T., at early stage, appears to be a local phenomenon which in itself is unable to perturb peripheral blood clotting tests.(Supported in part by a Grant of Inserm: ATP-12-74-33.)
Deep Venous Thrombosis of the Legs after Strokes: Incidence, Natural History and Predisposing Factors
Authors: Warlow Charles , Ogston D. , Douglas A. S. 
Published: June 2019

Forty of 76 patients who had sustained a cerebro-vascular’ accident developed a deep venous thrombosis of the paralysed leg as detected by the 125I-fibrinogen technique. A further 5 also had a thrombosis in the non-paralysed leg. ‘Definite’ pulmonary embolism, diagnosed at necropsy or by unequivocal clinical criteria, occurred in 9.2% of patients and ‘probable’ embolism, diagnosed on clinical examination and chest x-ray only, occurred in another 6.6% of patients Within the limitations of the 125I-fibrinogen technique it appeared that, in patients after cerebrovascular accidents, thrombosis developed in several independent sites in the venous system of the legs and propagation of the thrombi took place in both a distal and proximal direction. Pulmonary embolism occurred, with one exception, only in patients with detectable leg vein thrombosis.None of the risk factors studied including age, sex, obesity, side of paralysis, past history of venous thromboembolism, neurological and cardiac states, and interval between onset of stroke and mobilisation was helpful in predicting the likelihood of development of venous thrombosis in the paralysed limb.
A Growth Factor – Another Product of the Platelet Release Reaction?
Authors: Busch C. , Westermark B. 
Published: June 2019

Platelets have been shown to be a source of a growth factor promoting growth of mouse fibroblasts (Kohlor and Lipton, 1974), monkey arterial smooth muscle cells (Ross et al., 1974) and human glial cells (Westermark and Wasteson, 1974). This study investigates whether the factor is a product of the platelet release reaction or if it is just a component of the cell liberated when it is completely destroyed. Thus human platelet rich plasma was incubated with 14C-serotonin, divided into fractions which were subjected to different releasing substances in different concentrations (thrombin, collagen, ADP and adrenaline). Supernatants of the spun fractions were added to human glial cell cultures and the growth promoting activity measured by 3H-thymidine incorporation.
Results: Growth stimulating activity was found to be released by all inducing substances, most efficiently by thrombin and collagen. The release of this activity showed a linear relationship with the of 14C-serotonin.
Conclusions: Release of a cell growth stimulating factor seems to be a part of the platelet release reaction. Such a mechanism if operating also in vivo could be of importance e.g. in repair of endothelial damage, regulation of endothelial cell turnover as well as in inflammation and repair in a broader sense.
Soluble Fibrin Monomer Complexes Demonstrated by Agarose Gel Filtration and by Adsorption on Insolubilized Fibrinogen. A Comparative Study
Authors: Hugo von R. , Hafter R. , Stemberger A. , Graeft H. 
Published: June 2019

Incubation of fibrinogen with small amounts of thrombin resulted in the occurrence of soluble fibrin monomer complexes. These complexes consisted predominantly of a derivative with a higher molecular weight than that of fibrinogen. It was characterized by its relative electrophoretic mobility in 5% PAA gel (0.28 × 10-5 cm2/V×sec) and its elution position prior to the fibrinogen peak following gel filtration. Using adsorption chromatography on insolubilized fibrinogen the derivative dissociated at a ratio of almost 1 : 1 into one part which was adsorbed and into fibrinogen which was not adsorbed. The part which was adsorbed seemed to be the thrombin mediated fibrin monomer. This study confirms the concept that dissociable dimeric fibrinogonfibrin monomer complexes occur after limited action of thrombin on fibrinogen.(Supported by DFG ; SFB 51, grant no. 2/Gra – B/6.)
Specific Patterns of Fibrinogen Proteolysis in Clinical Syndromes Revealed by Fibrinopeptide Assays
Authors: Nossel H. L. , Ti M. , Soland T. , Spanondis K. S. , Canfield R. E. , Butler V. P. 
Published: June 2019

Specific radioimmunoassays were used to study fibrinopeptide cleavage from fibrinogen. Thrombin cleaves fibrinopeptide A (FPA) more rapidly than fibrinopeptide B (FPB) whereas plasmin cleaves a peptide with FPB immunoreactivity much more rapidly than FPA. Clinical blood samples manifested several distinct patterns of fibrinopeptide release (mean values in table).The elevated FPA level is interpreted as signifying increased thrombin action in vivo. A rapid FPA generation rate is thought to signify a uniformly elevated blood thrombin concentration whereas a low FPA generation rate in the presence of an elevated FPA level is thought to signify localized thrombin action. Elevated FPB immunoreactivity is postulated to reflect excessive plasmin action on fibrinogen.
The Effect of 6-Substituted Imidazo(4,5-b)Pyridines on Vitamin K-Dependent Procoagulants in Dogs, Warfarin-Sensitive and Resistant Rats
Authors: Bang N. U. , O’Doherty G. O. P. , Barton R. D. 
Published: June 2019

Dogs and warfarin-sensitive rats chronically fed a series of 6-substituted imidazo (4,5-b)-pyridines (6-I[4,5-b]P)General structure:died with a picture of generalized hemorrhage. The mechanism of action of these compounds was a selective suppression of the activities of vitamin K-dependent clotting factors II, VII, IX and X. Like warfarin, 6-I(4,5-b)P were significantly more effective in suppressing vitamin K -dependent clotting factor activities in male than in female rats. Rats proven resistant to warfarin also exhibited resistance to 6-I(4,5-b)P. Menadione sodium bisulphite did not antagonize the suppression of vitamin K-dependent clotting factor activities by 6-I(4,5-b)P. 6-I(4,5 -b)P structurally far removed from either vitamin K or the conventional vitamin K antagonists, the coumarins and indandiones may represent important tools to further elucidate the chain of events leading to vitamin K-dependent procoagulant synthesis and in pinpointing the biochemical defect responsible for warfarin resistance.
Heparin and Factor XaI Levels in Patients Undergoing Hip Surgery
Authors: Thomas Duncan P. , Sagar S. , Kakkar V. V. 
Published: June 2019

Plasma heparin and activated Factor X inhibitor (Xal) levels were measured in 25 patients undergoing total hip replacement. Blood samples were taken before, during and for 5 days after operation. In patients receiving heparin prophylaxis, over 50% of samples taken four hours after a subcutaneous injection of 5,000 units had no detectable plasma heparin; in none of the remaining samples did the level exceed 0.04 units per ml. In patients who developed deep vein thrombosis (DVT) postoperatively, as detected by 125-I-labelled fibrinogen and confirmed by venography, the mean preoperative level of Factor XaI was 73.5% (S. E. M.±6.9). In those patients who did not develop DVT, the mean preoperative level was 101.5% (S. E.M.±4.3) (P > 0.01).It is concluded that a regimen of 5,000 units 8-hour’ly does not give sustained plasma heparin levels after total hip replacement, which may in part explain the reduced effectiveness of low-dose heparin in preventing DVT in patients undergoing hip surgery. Low levels of Factor XaI in the immediate preoperative period correlated well with the subsequent development of thrombosis in these patients.
C-W Ultrasound Evaluation of Chronic Peripheral Arterial Disease Treated by i. v. Brinase
Authors: FitzGerald D. E. , Frisch E. P. 
Published: June 2019

Fortyfour patients with chronically obstructed peripheral arteries have been treated intravenously with brinase. Twentyfour of these patients had rest pain or gangrene (Stage III or IV) and 20 were claudicants (Stage II).Assessment before and after treatment was by clinical evaluation, blood pressure measurement in the limbs, and C-W ultrasound scanning of the peripheral arteries (Three arterial segments in each limb). Individual dosage requirement was decided by the level of brinase inhibitors in plasma. The more severely diseased patients were anti coagulated with Warfarin. The follow-up period from treatment extends from six months to three years.At the end of brinase treatment, good clinical improvement was obtained in 11/20 Stage IT, 10/12 Stage III, and 10/12 Stage IV. The arm-leg blood pressure gradient before treatment in Stage II was 88±41 mmHg, in Stage III 108±43 mmHg, and in Stage IV 129 ±45 mmHg. In patients responding to brinase treatment (27/44) a post-treatment gradient of 44±27 mmHg was recorded. In patients who failed to improve the higher gradient of 81 ±49 mmHg was retained.C-W ultrasound scanning of 228 arterial segments before treatment showed that 67 segments were occluded, 101 stenosed and 60 segments without significant lesions. Following treatment 19 segments remained occluded, 122 showed stenosis and 87 were without significant lesions. The post-treatment figures indicate a reduction in severity of arterial lesions.