bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of 24 Hours of Normoglycaemia on Tissue-Type Plasminogen Activator Plasma Levels in Insulin Dependent Diabetes
Authors: Juhan-Vague I , Vague P , Poisson C , Aillaud M F , Mendez C , Collen D
Published: July 2018

We have previously demonstrated that a short period of normoglycaemia obtained through an artificial pancreas in uncontrolled insulin-dependent diabetics improves parameters of the functional microangiopathy such as erythrocyte deformability and platelet aggregation. Because recently an immunoradiometric assay for tissue plasminogen activator (t-PA) was developed we measured t-PA levels in 18 uncontrolled insulin-dependent diabetics before and after 24 hr of normoglycaemia induced by insulin to look for a modification of endothelial cells function. After 24 hr of strict control, plasma free insulin levels rose significantly, total t-PA R-Ag, its active fibrin binding fraction and euglobulin fibrinolytic activity were significantly decreased. These results suggest a responsibility for insulin in the decrease in t-PA blood level and could explain at least partially the relation between hyperinsulinism, thrombosis and atherogenesis.
Platelet Aggregation Caused by Dithiothreitol
Authors: Zucker M B , Masiello N C
Published: July 2018

MacIntyre et al. showed that over 1 mM dithiothreitol (DTT) aggregates blood platelets in the presence of fibrinogen; aggregation is not inhibited by prostaglandin E1. We confirmed their data and found that 70 mM 2-mercaptoethanol was also active. DTT- induced aggregation was not associated with platelet shape change or secretion of dense granule contents, was not inhibited by tetracaine or metabolic inhibitors, was prevented at pH 6.5, and prevented, reversed, or arrested by EDTA, depending on when the EDTA was added. DTT did not cause aggregation of thrombasthenic, EDTA-treated, or cold (0° C) platelets, which also failed to aggregate with ADP. Platelets stimulated with DTT bound 125I-labeled fibrinogen. Thus DTT appears to “expose” the fibrinogen receptors. SDS gel electrophoresis of platelet fractions prepared by use of Triton X-114 showed that aggregating concentrations of DTT reduced proteins of apparent Mr 69,000 and 52,000 (probably platelet albumin) and, to a variable extent, glycoproteins Ib, IIb and III. Exposure of unlabeled or 125I- labeled platelets to ADP had no discernible effect on the electrophoretic patterns.
A New Platelet Aggregating Material (PAM) in an Experimentally Induced Rat Fibrosarcoma
Authors: Mohanty D , Hilgard P
Published: July 2018

The present work concerns our studies to search for factor(s) which may influence the hemostatic process in or around metastasis of tumours. We studied the platelet aggregating property of a methyl cholanthrene induced experimental tumour. Platelet aggregating material was found to be different from the known aggregating agents like thrombin, ADP, collagen, thromboxane A2 and trypsin. It depends on a critical level of calcium for its action. PAM is a high molecular weight substance which contains sialic acid. It is trypsin and plasmin insensitive. The activity of this substance is not being destroyed by phospholipase-C. Metabolic study indicates that PAM acts by mitochondrial energy metabolic pathway of the platelets.
Effects of Human Antithrombin III on Mortality and Blood Coagulation Induced in Rabbits by Endotoxin
Authors: Triantaphyllopoulos D C
Published: July 2018

Twenty-one rabbits were infused with 20μg/kg/hr of E. coli endotoxin for 6 hr. Eight of the animals were preinjected immediately before the infusion of endotoxin, with a bolus dose of human AT III calculated to increase the antithrombin content of the plasma by about 4 units/ml. All eight animals which were preinjected with AT III survived, while 5 of the 13 control rabbits infused with endotoxin alone died. The changes in coagulation parameters from the baseline values, between the 8 control rabbits which survived and the 8 animals which were preinjected with AT III were compared. The concentration of the preinjected human AT III declined significantly faster (P: <0.01) than that of the native rabbit AT III. AT III prevented the decline of F.XII throughout the infusion of the endotoxin. However, the decline in F.V, fibrinogen, prothrombin and platelets was not affected (P: >0.5) by the injection of AT III.
A Comparative Randomized Trial of Low-Dose Versus High-Dose Streptokinase in Deep Vein Thrombosis of the Thigh
Authors: Schulman Sam , Lockner Dieter , Granqvist Staffan , Bratt Göran , Paul Christer , Nyman Dag
Published: July 2018

Fibrinolytic treatment of acute deep vein thrombosis (DVT) of the leg with high-dose streptokinase (SK) (100,000 U/h) in 39 cases, or low-dose SK (approx 10,000 U/h) in combination with low-dose heparin in 41 cases, was studied in a prospective randomized trial. The degree of thrombolysis was similar in both groups and did not correlate with age or size of the thrombus or with fibrinogen level. The degree of late recanalization was also similar in both groups. There were however significantly more patients with postthrombotic changes in the low-dose group than in the high-dose group after a mean follow-up time of 31 and 38 months respectively. In the low-dose group 2 intracranial hemorrhages occurred (one was fatal) and one patient died of pulmonary embolism, but there were significantly less allergic side effects to SK. There were no cases of such serious side effects in the highdose group. Although low-dose SK has equal thrombolytic effect it seems inferior to high-dose SK, since it probably causes more severe hemorrhagic side-effects.
The Establishment of a Standard for Plasminogen (Glu-Type)
Authors: Gaffney P J , Curtis A D
Published: July 2018

Following an international collaborative study, a preparation of glutamic acid-(glu-)human plasminogen was established as a British Standard. This study compared the activity of the proposed standard following full activation to plasmin with the 2nd International Reference Preparation (IRP) for plasmin using both fibrinolytic and chromogenic assays. There was good agreement between the results of the two assay methods. The activity of the standard was 10 units per ampoule, these units being equivalent to those defined by the 2nd IRP for plasmin.
The Increased Sensitivity of Platelets to Prostacyclin in Marathon Runners
Authors: Dix Clive J , Hassall David G , Bruckdorfer K Richard
Published: July 2018

Platelet-rich plasma was obtained 24 hr after the race ended from athletes who ran in the London marathon. The platelets were only marginally less sensitive to adrenaline than were those of non-runners using conventional aggregation tests. However, the runners’ platelets were much more sensitive to inhibition by prostacyclin, a prostaglandin synthesized by endothelial cells. It appeared that this effect was due to a greater activity in the platelets of the membrane-bound adenylate cyclase enzyme which generates intracellular cyclic AMP. Cyclic AMP production is known to be stimulated by prostacyclin and to cause the inhibition of platelet aggregation. The results indicate another possible protective effect of exercise against cardiovascular disease which is independent of the known changes in lipoprotein concentrations previously observed in athletes.
Anticoagulant Properties of Purified X-Like Fragments of Human Fibrinogen Produced by Degradation with Leukocyte Elastase
Authors: Sterrenberg Lydi , van Liempt Gert Jan , Nieuwenhuizen Willem , Hermans Jo
Published: July 2018

The anticoagulant properties of fibrinogen digestion products change with stage of digestion. On digestion with leukocyte elastase, in the presence of calcium ions, the anticoagulant potency of fibrinogen digests first increases, then decreases sharply, and in late stages increases again. This is different from plasmin digestion where only an increase in anticoagulant activity is seen followed by a slow decrease.

From SDS-gel electrophoresis it appears that both the early rise and the decrease in anticoagulant activity are associated with the stage of elastase-produced X-like fragments. This is confirmed with pure fragments: X-like fragments (purified from elastase digests of fibrinogen of different stages by ammonium sulphate precipitation and ion-exchange chromatography) give an increase and decrease in anticlotting activity which correlates very well with that of the potency of the digest from which they are purified. As expected, and in contrast with (late) plasmic X- fragments, late elastase X-like fragments have a low anticoagulant potency. The molecular basis for the gain and loss in anticoagulant activity going from early to late X-like fragments is obscure. Immunological tests, calcium-binding experiments and affinity chromatography on immobilized thrombin-activated NDSK suggest that the changes in anticoagulant activity are not due to a proteolytic change in the carboxyl-terminal part of the γ-chain in the D moiety of the molecule. Our data suggest a correlation with the stage of digestion of the Aa-chain in the X-like fragments.
Biological and Thrombolytic Properties of Proenzyme and Active Forms of Human Urokinase – III. Thrombolytic Properties of Natural and Recombinant Urokinase in Rabbits with Experimental Jugular Vein Thrombosis
Authors: Collen D , Stassen J M , Blaber M , Winkler M , Verstraete M
Published: July 2018

The thrombolytic properties of recombinant pro-urokinase (Rec-pro-UK), recombinant active urokinase (Rec-UK) and natural urinary urokinase (Nat-UK) were compared with those of tissue-type plasminogen activator (t-PA) in rabbits with a radiolabeled thrombus in the jugular vein. The thrombolytic agents were infused intravenously over a time period of 4 hr and the extent of thrombolysis measured two hours later.

In control animals the extent of thrombolysis was 11 ± 2% (n=8) after 6 hr. Nat-UK and Rec-UK had very similar thrombolytic properties. Significant thrombolysis was only obtained with infusion of 240,000 IU per kg (41 ± 2%, n=4 for Nat-UK and 37 ± 4%, n=4 for Rec-UK) and this was associated with a marked systemic activation of the fibrinolytic system, as evidenced by consumption of plasminogen and α2-antiplasmin and fibrinogen breakdown.

Infusion of Rec-pro-UK induced thrombolysis at a dose of 60,000 IU per kg (44 ± 8%, n=3) but without associated systemic activation of the fibrinolytic system. In this respect the properties of Rec-pro-UK were similar to those of t-PA, which, however, had a 2- to 4-fold higher specific thrombolytic activity (30,000 IU/ kg yielding 48 ± 1% lysis, n=4).

It is concluded that Rec-UK has very similar thrombolytic properties as Nat-UK and that Rec-pro-UK has a beter thrombus- selectivity and less systemic side effects than the active enzymes.
Evaluation of Dose and Route Effects of Platelet Activating Factor-Induced Extravasation in the Guinea Pig
Authors: Handley Dean A , Van Valen Ronald G , Melden Mary Kay , Saunders Robert N
Published: July 2018

Platelet-activating factor (PAF) is a naturally occurring lipid that is reported to induce vessel hyperpermeability leading to loss of protein-rich plasma (extravasation). We have quantitated the systemic extravasation effects of synthetic PAF in the guinea pig by monitoring increases in hematocrit. When given intravenously (10-170 ng/kg), PAF produced dose-dependent increases in hematocrit, with maximal hemoconcentration developing in 5-7 min. In leukopenic animals the expected hematocrit increase was reduced by 57%. PAF given intra-arterially produced the dose-dependent changes in hematocrit similar to the intravenous effects of PAF. However, PAF given intraperitoneally (10-2500 μg/kg) was 800-1100-fold less effective than the other routes and hemoconcentration continued for 30-45 min until a maximal hematocrit was observed. These results show that PAF may markedly influence extravasation of plasma in a dose and route-dependent manner.
Platelet Accumulation on Collagen: Drugs Which Inhibit Arachidonic Acid Metabolism and Affect Intracellular Cyclic AMP Levels
Authors: Adams G A , Feuerstein I A
Published: July 2018

We have studied the accumulation of washed platelets on collagen-coated glass from flowing platelet-red blood cell suspensions in the presence and absence of drugs. Glass tubes were 10 cm long and the flow rate was 1 ml/min, 80 s-1. For all experiments, platelet accumulation was greatest near the tube’s inlet with a continuous decrease to the exit. A common feature, of those drug treatments which lead to reduced accumulation at the inlet, was an increase in outlet accumulation when compared with outlet control values. Platelet-collagen adhesion resulted in maximal release of 3H-serotonin in the presence of agents that prevent platelet aggregation on collagen. Only drug treatment known to raise cAMP levels (PGE1 and dipyridamole) or prevent the formation of prostaglandins and thromboxanes (sulfinpyrazone, indomethacin and ASA) were found to inhibit aggregate growth. Platelet aggregation on collagen in the absence of thrombin likely proceeds through the liberation of prostaglandins and thromboxanes from surface-bound platelets into the flow where they may stimulate flow-bom cells. An alternate hypothesis is that such treatments affect the release of a-granule components necessary for aggregation.
Elimination of Intravenously Administered Radiolabelled Antithrombin III and Heparin in Humans
Authors: de Swart Cees A M , Nijmeyer Bertha , Andersson Lars-Olov , Holmer Erik , Sixma Jan J , Bouma Bonno N
Published: July 2018

Antithrombin III was purified from normal plasma by DEAE- Sephadex chromatography and heparin affinity chromatography; the protein was subsequently radiolabelled with 125I. 125I-anti- thrombin III alone and 125I-antithrombin III in the presence of high affinity 35S-heparin fractions were injected into normal humans. 125I-radiolabel and protein bound 35S-radioactivity were followed separately. In semilogarithmic plots 125I-antithrombin III disappeared according to a double exponential curve with a half-life in the second phase of 56.8 hr in the absence of heparin and of 33.7 hr in the presence of heparin. Protein bound 35S- radioactivity disappeared much faster than the 125I-radiolabel. These data support the concept that heparin disappears as free heparin from the equilibrium heparin – antithrombin III ⇄ heparin + antithrombin III. Immuno-reactive antithrombin III decreased from 100% to 85-90% immediately after injection of 125I-antithrombin III in the presence of heparin and returned to normal values within 30 min. This suggests that antithrombin III is transiently sequestered, possibly in trimolecular complexes consisting of antithrombin III, heparin and either lipases or other vascular bound proteins.
The Mesothelial Cell as a Non-Thrombogenic Surface
Authors: Nicholson L J , Clarke J M F , Pittilo R M , Machin S J , Woolf N
Published: July 2018

A technique for harvesting mesothelial cells is described. This entails collagenase digestion of omentum after which the cells can be cultured. The technique has been developed using the rat, but has also been successfully applied to human tissue. Cultured rat mesothelial cells obtained in this way have been examined by scanning electron microscopy. Rat mesothelial cells grown on plastic film have been exposed to blood in an in vitro system using a Baumgartner chamber and have been demonstrated to support blood flow. No adhering platelets were observed on the mesothelial cell surface. Fibroblasts similarily exposed to blood as a control were washed off the plastic.
Uptake and Catabolism of 125l-Thrombin by the Rabbit Thoracic Aorta In Vitro: Permeability of the Endothelium, Intima-Media and Adventitial Layers
Authors: Hatton Mark W C , Moar Sue L
Published: July 2018

The uptake, distribution and catabolism of 125I-thrombin has been studied in vitro using normal and ballooned (de-endothelialized) aorta segments at 37° C and at 4° C. In addition to rapid uptake by endothelial cells, 125I-thrombin passed at a slower, and yet constant, rate through the endothelium and accumulated in the intima-medial and adventitial layers. The enzyme, however, was not able to cross the adventitia. Passage through the endothelium was probably intercellular rather than due to transcytosis. Uptake by the intima-media layer of ballooned segments was substantially faster (× 2.5) than by the subendothelial (intima-media) region of normal segments. Once associated with the endothelium and the subendothelial layers, 125I-thrombin was catabolized and radioactive products, which were released from the vessel wall, appeared in the incubation medium. Two possible catabolic routes were identified: 1. the enzyme was recovered as a high molecular weight product (i. e. excluded by Sephadex G-200), due to complex formation with an extracellular vessel wall component and/or plasma antithrombin III. 2. Fragments of the enzyme were recovered which were presumably the products of limited, extracellular proteolysis.
Disappearance of Antibodies to Factor VIII in a Patient with Acquired Haemophilia and Carcinoma of the Pancreas During Cytotoxic Therapy with Fluorouracil and CCNU
Authors: Rhodes E G H , Boesen E A M , Corringham R E T , Matthews K B , Tuddenham E G D , Kernoff P B A
Published: July 2018

An inhibitor to clotting factor VIII (anti-VIII: C) developed in a 70 year old woman with carcinoma of the pancreas three months after palliative by-pass surgery. A life-threatening sublingual haemorrhage was controlled by infusion of human factor VIII concentrate in high dosage. With the objective of reducing pancreatic tumour size, combination cytotoxic therapy with fluorouracil and CCNU was given. Reduction in the size of the tumour was associated with disappearance of anti-VIII:C, reappearance of normal quantities of clotting factor VIII (VIII: C) in the plasma and resolution of the bleeding tendency. The anti-VIII: C was characterised as being predominantly of the IgG4 sub-class with k light chains. In vitro and in vivo studies showed the inactivation of VIII: C by anti-VIII: C was markedly non-linear. Normal quantities of factor VIII coagulant antigen (VIII: CAg) were detected in the patient’s plasma when VIII: C levels were negligible.
Fifteen Coagulation and Fibrinolysis Parameters in Diabetes Mellitus and in Patients with Vasculopathy
Authors: Christe M , Fritschi J , Lämmle B , Tran T H , Marbet G A , Berger W , Duckert F
Published: July 2018

Fifteen haemostasis parameters have been measured in 48 normal persons, 36 diabetics without and 44 with complications and 27 with peripheral arterial disease. Since the patients groups are older than normals, part of the differences are due to age. However, the differences are significant between normals and patients. They become highly significant for the diabetics with complications and nephropathy (Table 7). In diabetics without complications factor VIII functions, fibrinogen and thrombin time are related to age whereas there is a negative correlation for the fibrinolytic activity and antithrombin III. The diabetic complications shade off the correlations, which subsist only for VIIIR: CoF, VIIIR: Ag, ATIII and lysis before stasis. With Hbalc as dependent variable VIIIR:CoF is the only significant predictor variable in diabetics (Table 9).
Platelet Production in Myocardial Infarction and Sudden Cardiac Death
Authors: Trowbridge E A , Slater D N , Kishk Y T , Woodcock B W , Martin J F
Published: July 2018

Megakaryocyte cytoplasmic volumes were studied in 13 subjects 18 ± 2 days after admittance to the coronary care unit. Seven had suffered a myocardial infarction (MI group) while six had chest pain but no recent infarction. Megakaryocytes were also studied in 10 subjects suffering coronary sudden unexpected death (CSD group) and 11 subjects suffering sudden unexpected un-natural death. There was no significant difference between the megakaryocyte cytoplasmic volume distributions of the MI and CSD groups, although they had a significantly greater mean (p <0.01) and range (p <0.001) than theirrespectivecontrolgroups.

There was no significant difference in platelet volumes observed within 24 hr of the infarct and 18 ± 2 days later. Mean platelet volume was significantly correlated (r = 0.89, p <0.006) to mean megakaryocyte cytoplasmic volume in the MI group. A computer simulation of platelet production showed no significant difference between platelet volumes observed in the MI group and those estimated to be circulating before death in the CSD group.
Assessment of Anti-Streptokinase Antibody Levels in Human Sera Using a Microradioimmunoassay Procedure
Authors: Moran D M , Standring R , Lavender E A , Harris G S
Published: July 2018

A high capacity, quantitative radioimmunoassay procedure has been developed to measure IgG antibodies to streptokinase (SK) in human serum. Results showed that the use of low concentrations of 125I-SK (100 ng/ml) and ambient temperature incubation conditions minimised degradation of the target labelled antigen and afforded antibody binding values which could be confidently related to the native intact SK protein. SK-complexed to plasminogen was also shown to retain the equivalent antigenic activity of native SK. Comparison of the absolute anti-SK levels with streptokinase resistance titres demonstrated that the two measurements of antibody correlated statistically but afforded quantitatively poor agreements. A survey of IgG levels to SK in sera from 93 normal healthy volunteers showed that all individuals displayed readily measurable anti-SK antibodies, with some 80% having IgG concentration capable of binding in excess of 1 μg SK per ml serum.
Serious Complications of Intraosseous Access during Infant Resuscitation
Authors: Molacek Jiri , Houdek Karel , Opatrný Václav , Fremuth Jiri , Sasek Lumir , Treskova Inka , Treska Vladislav
Published: July 2018

We report on a 2.5-month-old infant with ischemia of the left leg and compartment following intraosseous needle application during resuscitation. Unfortunately, this event led to major limb amputation. The cause, mechanism, and prevention of this severe complication are discussed in this article.
Mechanism of the Antiplatelet Action of Dipyridamole in Whole Blood: Modulation of Adenosine Concentration and Activity
Authors: Gresele Paolo , Arnout Jef , Deckmyn Hans , Vermylen Jos
Published: July 2018

Dipyridamole inhibits platelet aggregation in whole blood at lower concentrations than in plasma. The blood cells responsible for increased effectiveness in blood are the erythrocytes. Using the impedance aggregometer we have carried out a series of pharmacological studies in vitro to elucidate the mechanism of action of dipyridamole in whole blood. Adenosine deaminase, an enzyme breaking down adenosine, reverses the inhibitory action of dipyridamole. Two different adenosine receptor antagonists, 5’-deoxy-5’-methylthioadenosine and theophylline, also partially neutralize the activity of dipyridamole in blood. Enprofylline, a phosphodiesterase inhibitor with almost no adenosine receptor antagonistic properties, potentiates the inhibition of platelet aggregation by dipyridamole. An inhibitory effect similar to that of dipyridamole can be obtained combining a pure adenosine uptake inhibitor (RE 102 BS) with a pure phosphodiesterase inhibitor (MX-MB 82 or enprofylline). Mixing the blood during preincubation with dipyridamole increases the degree of inhibition. Lowering the haematocrit slightly reduces the effectiveness.

Although we did not carry out direct measurements of adenosine levels, the results of our pharmacological studies clearly show that dipyridamole inhibits platelet aggregation in whole blood by blocking the reuptake of adenosine formed from precursors released by red blood cells following microtrauma. Its slight phosphodiesterase inhibitory action potentiates the effects of adenosine on platelets.
Heparin Cofactor II: Purification and Antibody Production
Authors: Tran Tri H , Lämmle B , Zbinden B , Duckert F
Published: July 2018

Heparin cofactor II (HCII) was purified from plasma to homogeneity. The procedure includes adsorption with (Al)OH3, fractionation with polyethylene glycol 6000, chromatography on QAE-Sephadex A-50, on heparin-Sepharose 4B and on Sephadex G-150. QAE-Sephadex A-50 chromatography provides a good separation of HCII from antithrombin III (AT) and most contaminants having a heparin affinity similar to that of HCII. HCII is eluted at 0.28 M NaCl from the heparin-Sepharose column. After gel filtration on G-150, contaminating AT was removed by immunoadsorption. Purified HCII shows an apparent Mr of 66,500 dal tons as analyzed on SDS-polyacrylamide gel and 62,100 daltons by ultracentrifugation. Antibodies to HCII were raised in rabbits. Former antisera mostly directed to a contaminating protein were used to remove it from the HCII preparation. Antibodies to HCII were made monospecific by immunoadsorption on HCII-free plasma linked to Sepharose 4B. Since many functional AT assays have neglected the presence of HCII in plasma, antibodies to HCII using as immunoadsorbent will provide a more specific test for AT.
Purification and Some Chemical Properties of Thrombin-Like Enzyme from Trimeresurus Flavoviridis Venom
Authors: Kosugi T , Ariga Y , Nakamura M , Kinjo K
Published: July 2018

There has been no previous report indicating whether thrombin-like enzyme is contained in the venomof Trimeresurus flavoviridis whichhas the strongest toxic effect in the case of Habu bite. The presentstudy was undertaken to clarify the existence of thrombin-like enzyme in Trimeresurus flavoviridis venom. As a starting material, lyophilized crude venom of Trimeresurus flavoviridis was used, and ammonium sulphate fractionation, gel filtration using Sephadex G-25, Sephadex G-150 and arginine-Sepharose affinity chromatography were carried out to separate and purify a thrombin-like enzyme from the crude venom. The enzyme was purified to a 137-fold increase in specific activity and the purified preparation revealed a single band on SDS-PAGE. The molecular weight of the enzyme was estimated to be 65,000-70,000 daltons by means of SDS-PAGE and gel filtration, and its isoelectric point was pH 4.5-5.5. Furthermore, the optimal pH of the enzyme was in the range of pH 8.0 to 8.5. Some of the differences in enzymatic properties between this enzyme and bovine thrombin were studied. The snake enzyme could coagulate only rabbit plasma and convert only purified rabbit fibrinogen to fibrin gel. In addition, this thrombin-like enzyme released only fibrinopeptide A from purified rabbit fibrinogen and did not release fibrinopeptide B.
Heparin-Associated Thrombocytopenia Treatment with Low Molecular Weight Heparin
Authors: Vitoux Jean-F , Mathieu Jean-F , Roncato Martine , Fiessinger Jean-N , Aiach Martine
Published: July 2018

Eight patients with heparin associated thrombocytopenia (HAT) were treated by a low molecular weight heparin derivative (LMW). Biological and clinical improvement occurred in all patients. This efficiency confirms the antithrombotic activity of LMW and allows its use in patients with HAT.
The Production and Characterisation of a Panel of Ten Murine Monoclonal Antibodies to Human Procoagulant Factor VIII
Authors: Griffin B D , Micklem L R , McCann M C , James K , Pepper D S
Published: July 2018

A panel of 10 murine monoclonal antibodies to procoagulant FVIII has been developed from the fusion of a single spleen. Balb/c mice were injected with a purified preparation of FVIII: Ag, and antibody production in sera and hybrid culture supernatants was monitored using a specific radiometric screening assay. The antibodies all inhibit FVIII clotting activity in normal plasma, and when immobilised on agarose retain their ability to recognise and bind the FVIII procoagulant protein. Studies on protein A-purified immunoglobulins demonstrate a range of properties within the panel of antibodies with regard to species crossreactivity, clotting inhibition and immunoadsorption. The panel of antibodies has been used to screen heat-treated FVIII concentrates for the occurrence of heat-induced neoantigens.
The Assay of Factor VIII: C in Heparinized Plasma: A Polybrene Neutralization Method
Authors: Cumming A M , Wensley R T , Delamore I W
Published: July 2018

Factor VIII coagulant activity (VIII: C) has been shown by several investigators to exhibit increased stability in vitro when physiological levels of plasma ionized calcium are maintained by anticoagulation with heparin rather than citrate. An increase in initial activity of VIII: C in heparin over that of VIII: C in citrate has been reported but this has not been confirmed. In order to assay VIII :C in heparinized plasma, the heparin anticoagulant effect must be excluded without interfering with the validity of the assay. A one-stage clotting assay for VIII: C has been developed where heparin is neutralized by Polybrene®, a synthetic polymerized quaternary ammonium salt. VIII :C may be accurately measured by this method which satisfies the requirements for a valid assay of parallelism and linearity.
Improved Characterization of Plasma von Willebrand Factor Heterogeneity when Using 2.5% Agarose Gel Electrophoresis
Authors: Mazurier Claudine , Samor Bruno , Goudemand Maurice
Published: July 2018

Discontinuous sodium dodecyl sulfate electrophoresis in large pore gels, followed by overlay with radiolabelled anti-von Willebrand factor (vWF) antibodies and by autoradiography, permits to analyze the multimeric structure of vWF. The aim of this study was to improve experimental conditions of this technique to satisfactorily resolve the minor forms of plasma vWF while still separating its high, intermediate, and low molecular weight predominant multimers. By using a 2.5% mixture of two selected agaroses, a single electrophoretic analysis of plasma clearly reveals the extreme complexity of the molecular forms of circulating vWF: each multimeric unit of plasma vWF may be separated into five bands, the central one being predominant. The multimeric distribution and “quintuplet” pattern obtained in the electrophoretic system described here permit a convenient classification of the different subtypes of von Willebrand’s disease.
Evaluation of the Cuticle Bleeding Time in Canine Haemophilia A
Authors: Pijnappels M I M , Briët E , Zwet G Th van der , Huisden R , Tilburg N H van , Eulderink F
Published: July 2018

In this paper we describe our clinical experience and results with the cuticle bleeding time test in a colony of cross-bred Labrador retrievers with severe haemophilia A. The dogs have a severe bleeding tendency with a high incidence of fatal haemorrhages in the central nervous system. Homozygous females appeared to be especially prone to this lethal complication. Factor VIII recovery and half-life determinations yielded results similar to the data from human studies. The cuticle bleeding time proved to be a good measure of the coagulation defect. The prolongation of the bleeding time could be completely abolished by administration of 10 to 15 units of canine factor VIII per kg body weight. We conclude that the cuticle bleeding time in canine haemophilia provides us with a suitable model for the in vivo study of new therapeutic materials.
Triton X-114 Phase Separation of Platelet Membrane Glycoproteins from Normal Subjects and a Patient with Type I Thrombasthenia
Authors: Khanduri U , Clark S , Walker I D , Chamberlain K G , Penington D G
Published: July 2018

Surface-labelled normal and thrombasthenic platelets have been subjected to phase separation in Triton X-114. Triton-rich and Triton-poor fractions have been analysed by SDS-PAGE and IEF-SDS-PAGE. Partitioning characteristics of the major glycoproteins have been defined. The Triton-rich fraction contained GPIIb, III, IV, VI, VII, VIII, GP38 and the IIb β subunit. In contrast, the Triton-poor fraction contained the HMWGP, GPIa, Ib, IIb, III, V and GPIX.

Analysis of the platelet membrane glycoproteins of a patient with Type 1 thrombasthenia has been carried out using Triton X-114. The value of the method in diagnosis of this condition and differences between our findings and those published previously are discussed.
Coextraction of Thrombomodulin and Tissue Factor from Human Placenta: Effects of Concanavalin A and Phospholipid Environment on Activity
Authors: Freyssinet Jean-Marie , Brami Brigitte , Gauchy Josiane , Cazenave Jean-Pierre
Published: July 2018

Thrombomodulin and tissue factor activities have been coextracted from human placenta by several non-ionic detergents, n-octylglucoside and Triton X-100 being the most efficient ones. The n-octylglucoside placenta extract had a strong cofactor activity in the activation of human protein C by human a-thrombin. Treatment of the n-octylglucoside and Triton X-100 placenta extracts by phospholipases C and A2 revealed that an adequate phospholipid environment is necessary for maximal thrombomodulin activity, while it is well known that this is crucial for tissue factor activity. Soluble concanavalin A reversibly inhibited thrombomodulin and tissue factor activities to the same extent. Con-A-Sepharose affinity chromatography of the Triton X-100 placenta extract resulted in the same proportion (30%) of these two activities bound to the lectin, which were subsequently eluted in the same fractions by a linear gradient of α-methyl-D-glucoside. This observation suggests that thrombomodulin activity is associated to a glycoprotein component presenting the same degree of carbohydrate heterogeneity, involving α-D-mannosyl or α-D-glucosyl residues, as tissue factor apoprotein. Relipidation of fraction eluted by α-methyl-D-glucoside was essential to detect tissue factor activity, it was also necessary to recover full thrombomodulin activity. An antibody to human brain tissue factor apoprotein inhibited human placenta tissue factor activity, whereas thrombomodulin activity was unaffected, suggesting that these two cellular activities are related to distinct molecular entities sharing striking functional and structural similarities.
Musculoskeletal Outcomes from Chronic High-Speed, High-Impulse Resistance Exercise
Authors: Caruso John , Voor Michael , Jaggers Jason , Symons T. , Stith Jeremy , Bai Ling , Selimovic Ema , Carter Kathy , Daily Jennifer
Published: July 2018

While bones and muscles adapt to mechanical loading, it appears that very specific types of stimuli must be applied to achieve osteogenesis. Our study assessed musculoskeletal outcomes to 30 training sessions on an Inertial Exercise Trainer (Newnan, GA). Subjects (n=13) performed workouts with their left leg, while their right served as an untreated control. Workouts entailed three 60-s sets each of knee extension, hip extension and calf press exercises, separated by 90-s rests. Before and after the 30 training sessions, subjects underwent strength tests (knee and ankle extensors of both legs), DEXA scans (hip, knee and ankles of both legs), and blood draws. After 30 training sessions 2×2 ANOVAs showed left leg peak torques rose significantly. 2×2 ANCOVAs, with bone scan area as a covariate, showed significant left leg calcaneal bone mineral content (+29%) and density (+33%) increases after 30 training sessions. A significant decline in C-terminal telopeptides of type I collagen, a blood marker of bone resorption, also occurred after 30 training sessions. The Inertial Exercise Trainer’s large volume of training session repetitions elicited high peak force, peak acceleration and impulses that likely provided a mechanical loading stimulus that evoked calcaneal accretion.
Algebraic approach to the Tavis-Cummings model with three modes of oscillation
Authors: Choreño E. , Ojeda-Guillén D. , Granados V. D.
Published: July 2018

We study the Tavis-Cummings model with three modes of oscillation by using four different algebraic methods: the Bogoliubov transformation, the normal-mode operators, and the tilting transformation of the SU(1, 1) and SU(2) groups. The algebraic method based on the Bogoliubov transformation and the normal-mode operators lets us obtain the energy spectrum and eigenfunctions of a particular case of the Tavis-Cummings model, while with the tilting transformation we are able to solve the most general case of this Hamiltonian. Finally, we compute some expectation values of this problem by means of the SU(1, 1) and SU(2) group theory.

The authors of the article agree to the retraction of the article effective 21 September 2023
Stress mapping of a strain superlattice using scanning moiré fringe imaging
Authors: Wen Huihui , Zhang Hongye , Liu Zhanwei , Liu Chao , Liu Shuman , Yang Xinan , Liu Fengqi , Xie Huimin
Published: July 2018

Accurate adjustment of the stress/strain field can significantly affect the physical properties of a strain compensation superlattice structure in quantum cascade lasers. Therefore, precise evaluation of the stress/strain is of significant importance at the nanoscale. In this investigation, nanometer-scale scanning moiré fringes (SMFs) with two directions in an In0.6Ga0.4As/In0.56Al0.44As superlattice structure are obtained simultaneously by precisely adjusting the formation parameters of SMF using scanning transmission electron microscopy (STEM). Starting from the principle of STEM imaging, the fundamental formation principle and forming condition of STEM moiré are systematically studied. The 2D strain/stress distributions parallel and vertical to the growth direction are measured simultaneously, indicating that the maximum absolute value of strain/stress is close to the interface, with the peak stress at the gigapascal level, whereas the minimum absolute value of strain/stress is near the middle of each layer. The calculated resultant force indicates that each In0.56Al0.44As layer provides effective strain compensation for the adjacent In0.6Ga0.4As layers. The active region is properly strain-balanced to provide a nearly net-zero strain within a single period, reducing the possibility of forming dislocations.
A real-time parallel data acquisition and big data processing method for four-in-one optical fiber sensor network
Authors: Zhu Wanshan , Jiang Junfeng , Wang Jin , Liu Xinggang , Liu Tiegen
Published: July 2018

We propose a real-time parallel data acquisition and big data processing method. This method can multiplex different types of fiber sensors and quickly complete the simultaneous sampling of thousands of sensors on hundreds of channels in four-parameter heterogeneous fiber sensor network, its sampling frequency is up to 6.4MHz, and the data throughput is up to 13.8MB/s. This method is three times faster than the usual method.
Structural and vibrational properties of SnxGe1-x: Modeling and experiments
Authors: Vasin A. S. , Oliveira F. , Cerqueira M. F. , Schulze J. , Vasilevskiy M. I.
Published: July 2018

The effects of the composition and macroscopic strain on the structural properties and lattice vibrations of SnxGe1-x solid solutions (SSs) are investigated numerically, employing Tersoff empirical inter-atomic potentials, and experimentally. The calculations provide statistical distributions of bond lengths, pair correlation function, and vibrational Raman spectra of the SSs. Using this approach, we are able to evaluate the tin-content-dependent shifts due to the local environment (i.e., changes in the atomic mass and bond stiffness) and strain effects in the calculated Raman spectra and compare them to experimental data. The relative importance of the composition dependent effects of the local environment and strain for epitaxial layers of GeSn solid solutions is analysed.
Peculiarities of plastic relaxation of (0001) InGaN epilayers and their consequences for pseudo-substrate application
Authors: Moneta J. , Siekacz M. , Grzanka E. , Schulz T. , Markurt T. , Albrecht M. , Smalc-Koziorowska J.
Published: July 2018

In this paper, we study the plastic relaxation of InGaN layers deposited on (0001) GaN bulk substrates and (0001) GaN/sapphire templates by molecular beam epitaxy. We demonstrate that the InGaN layers relax by the formation of (a+c)-type misfit dislocations gliding on pyramidal planes in the slip system ⟨112¯3⟩{112¯2} down to the interface where they form a trigonal dislocation network. Combining diffraction contrast and large angle convergent beam electron diffraction analyses performed using a transmission electron microscope, we reveal that all (a+c)-type dislocations belonging to one subset of the network exhibit Burgers vectors with the same c-component. This relaxation mechanism leads to partially relaxed InGaN layers with smooth surfaces and threading dislocation densities below 109 cm−2. Such layers are of potential interest as pseudo-substrates for the growth of InGaN heterostructures.
Normal and resonant Auger spectroscopy of isocyanic acid, HNCO
Authors: Holzmeier F. , Wolf T. J. A. , Gienger C. , Wagner I. , Bozek J. , Nandi S. , Nicolas C. , Fischer I. , Gühr M. , Fink R. F.
Published: July 2018

In this paper, we investigate HNCO by resonant and nonresonant Auger electron spectroscopy at the K-edges of carbon, nitrogen, and oxygen, employing soft X-ray synchrotron radiation. In comparison with the isosteric but linear CO2 molecule, spectra of the bent HNCO molecule are similar but more complex due to its reduced symmetry, wherein the degeneracy of the π-orbitals is lifted. Resonant Auger electron spectra are presented at different photon energies over the first core-excited 1s → 10a′ resonance. All Auger electron spectra are assigned based on ab initio configuration interaction computations combined with the one-center approximation for Auger intensities and moment theory to consider vibrational motion. The calculated spectra were scaled by a newly introduced energy scaling factor, and generally, good agreement is found between experiment and theory for normal as well as resonant Auger electron spectra. A comparison of resonant Auger spectra with nonresonant Auger structures shows a slight broadening as well as a shift of the former spectra between −8 and −9 eV due to the spectating electron. Since HNCO is a small molecule and contains the four most abundant atoms of organic molecules, the reported Auger electron decay spectra will provide a benchmark for further theoretical approaches in the computation of core electron spectra.
MgB2 Josephson junctions produced by focused helium ion beam irradiation
Authors: Kasaei L. , Melbourne T. , Manichev V. , Feldman L. C. , Gustafsson T. , Chen Ke , Xi X. X. , Davidson B. A.
Published: July 2018

Planar magnesium diboride Josephson junctions are fabricated using focused helium ion beam irradiation. A single track of ion irradiation with a 30 kV He+ beam with nominal beam diameter < 0.5 nm is used to create a normal-metal barrier on a MgB2 film deposited by hybrid physical-chemical vapor deposition. Josephson coupling is observed below the critical temperature of the electrodes for a He+ doses between 8x1015/cm2 to 4x1016/cm2. Analysis of the temperature dependence of the normal resistance and critical voltage of the junctions shows highly uniform barriers with nearly ideal resistively-shunted junction behavior for higher-dose junctions, while nonequilibrium effects dominate the properties of lower-dose junctions over most of the temperature range. These results demonstrate that focused helium ion beam irradiation can produce high-quality proximity-coupled MgB2 Josephson junctions with tailorable properties, promising for use in superconducting devices and circuits.
Calculation of the propagator of Schrödinger’s equation on (0, ∞) with the potential kx−2 + ω2x2 by Laplace’s method
Authors: Ortner Norbert , Wagner Peter
Published: July 2018

Using Laplace’s method, Green’s function of the operator ∂t−12∂x2+k2x−2+12ω2x2,k≥−14, ω≥0 is calculated in the half-space x > 0. Therefrom, we deduce the propagator of Schrödinger’s equation with the potential V(x) = kx−2 + ω2x2 for k≥34.
Decay of nonlinear whistler mode waves: 1D versus 2D
Authors: Umeda Takayuki , Saito Shinji , Nariyuki Yasuhiro
Published: July 2018

Direct comparison between one-dimensional (1D) and two-dimensional (2D) models for the development of a nonlinear, short-wavelength, and monochromatic electromagnetic whistler mode wave is made by means of fully electromagnetic particle-in-cell simulations. The 1D and 2D simulations are performed for low beta conditions in which the plasma pressure is much lower than the magnetic pressure, although the plasma kinetic energy in the direction perpendicular to the ambient magnetic field is highly dominant due to the velocity field of the imposed parent whistler mode wave. A three-wave parametric decay of the parent whistler mode wave was reconfirmed in the 1D simulation. On the other hand, a rapid decay of the parent whistler mode wave thorough a five-wave interaction or double three-wave interactions was seen in the 2D simulation. Electron heating processes in the 2D simulation are also different from those in the 1D simulation. It is suggested that the present 2D decay process is a new instability which is quite different from velocity space instabilities driven by temperature/energy anisotropy.
Effect of high-pressure torsion on the microstructure and thermoelectric properties of Fe2VAl-based compounds
Authors: Masuda S. , Tsuchiya K. , Qiang J. , Miyazaki H. , Nishino Y.
Published: July 2018

Heusler-type Fe2VAl thermoelectric materials have been processed by high-pressure torsion (HPT) to improve their thermoelectric performance through a drastic reduction of the thermal conductivity. While the thermal conductivity for Fe2VTa0.05Al0.95 is about 10 W/m K at 300 K, it is reduced to about 5.0 W/m K due to HPT processing. Furthermore, even after annealing at 873 K for recurrence of the Heusler-type structure, Ta-doped Fe2VTa0.05Al0.95 possesses an ultra-fine grained structure with an average grain size of about 80 nm, in contrast to the presence of large grains of about 270 nm for non-doped Fe2V1.05Al0.95. Since scanning transmission electron microscopy combined with energy-dispersive X-ray analysis reveals the solute segregation of Ta along grain boundaries and recrystallization interfaces, the retardation of recrystallization could be caused by the solute drag effect, leading to a suppression of grain coarsening. Thus, it is possible to retain the low thermal conductivity of about 5.0 W/m K at 300 K for Fe2VTa0.05Al0.95, in parallel with the restoration of a large power factor, so that the dimensionless figure of merit reaches ZT = 0.30 at around 500 K.
1-Dimensional quantitative micro-architecture mapping of multiple scattering media using backscattering of ultrasound in the near-field: Application to nodule imaging in the lungs
Authors: Mohanty Kaustav , Blackwell John , Masuodi S. Behrooz , Ali Mir Hasnain , Egan Thomas , Muller Marie
Published: July 2018

In this letter, we present a near-field method for mapping the micro-architecture of complex media based on the measurement of the diffusion constant D using multiple backscattering of ultrasound waves. Simulation results are reported and validated with experiments. For both simulations and experiments, a linear array of ultrasound transducers is used. The coherent and incoherent intensities are separated using a matrix manipulation of the inter-element response matrix. We demonstrate that no beamforming is necessary to extract the diffusion constant. Acquiring sub-inter-element response matrices by using subsets of elements and calculating the growth of the diffusive halo for each sub-matrix provides an estimate of a semi-local diffusion constant, enabling a 1-D mapping of the scatterer density or volume fraction in a strongly heterogeneous medium. This methodology is then applied to quantitatively characterize the lung parenchyma and detect the presence of solitary pulmonary nodules. The semi-local diffusion constant is mapped along the transducer axis to search for high D values, which correspond to the nodule/lesion location.