bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamics of a beam on elastic foundation - impact of the bilinear characteristic of the foundation upon the propagation of the bending wave
Authors: Mazilu Traian , Cruceanu Cristian Ioan
Published: July 2018

Rail is an important source of noise in the railway traffic and its acoustic power is depending on the rate of decay of vibration. The main characteristic of the track in terms of the vertical elasticity is the so-called track modulus which results from the load-rail deflection curve. In general, this curve is nonlinear and it can be approximated using piecewise linear function with bilinear characteristic. In this paper, the response of a beam on elastic foundation with bilinear characteristic due to constant and harmonic loads is investigated, pointing out the impact of the foundation characteristic on the rail response and the propagation of the bending waves along the track.
Positioning study of driver's hands in certain areas of the steering wheel
Authors: Amortila Valentin , Mereuta Elena , Veresiu Silvia , Rus Madalina , Humelnicu Costel
Published: July 2018

The aim of this paper is to analyze driver's hands coordinates on the steering wheel for an optimal and safe driving experience. A good coordination of the driver's action on the controls is the result of a comfortable position that leads to an optimal reaction while driving. The presented study implies using a thermal imaging camera for analysing palms temperature changes in the contact area with the steering wheel. The resulting data shows that the optimal driving position of drivers' hands is 0° and 180° associating the steering wheel with and trigonometric circle.
Use of the experimental modal analysis for analytical lifetime estimation of a bogie frame
Authors: Manea Ion , Sebesan Ioan , Matache Mihai , Prenta Gabriel , Firicel Catalin
Published: July 2018

The fatigue strength validation by tests of the railway bogie frames requires existence of an expensive laboratory and a long time for testing of about 6 to 10 months. Considering these aspects, the European norms admit that fatigue tests can be replaced by finite elements analysis (FEA), with the condition that analytical model to be correctly realized and validated by tests. Experimental modal analysis (EMA) provides a powerful tool for validation of the FEA model by experimental data. The article presents an application for assessment of the fatigue strength of a three-axle locomotive bogie frame. Using Ansys, was carried out the structural analysis of the bogie frame, resulting the modal model characterized by the modal parameters: Eigen frequencies and Eigen shapes. The analytical model was validated by an EMA application carried out on the bogie frame and correlation analysis of the EMA and FEA models. Using a special measuring wheel set, were determined the wheelrail interaction forces for various locomotive running conditions. The analytical structural model, validated through experimental data, and the data files containing the wheel-rail interaction forces, constitutes the input data for the nCode program that evaluates the bogie frame lifetime using appropriate stress curves and a recognized accumulation of damage hypothesis, e.g. the Palmgren-Miner.
Necessity and conditionality regarding the electromagnetic track brake - parametric study
Authors: Cruceanu Cătălin , Crăciun Camil
Published: July 2018

The paper explores the speed limits requiring additional braking systems independent of rail/wheel adhesion. Regarding the electromagnetic track brake (MTB), conditions to achieve the safety traffic requirements for stopping distances and decelerations are investigated by means of numerical simulations. The computing program integrates the movement equation of the vehicle, taking into account weight, resistance to forward movement, etc. The study is performed for 40...60 t four axles passenger vehicles and it was considered a speed domain of 160...300 km/h. The results indicate that deceleration requirements are an important limitative parameter for constructive top speeds of railway vehicles. For velocities higher than 210...230 km/h, the braking distances exceed the possibility of running under conventional signalling system.
Influence of the rail dampers on the frequencydomain response of the rail
Authors: Mazilu Traian , Fologea Dorina
Published: July 2018

Rail dampers are mechanical devices mounted at both sides of the rail web aiming to reduce the vibration along the rail. In this way, a shorter length of the rail vibrates effectively and the rolling noise is less intense. In this paper, a continuous model consisting in an infinite Timoshenko beam on multi-elastic layers is adopted for the railway track with rail dampers. The equations of motion are solved using the Green's function method and the frequency-response of UIC 49 rail is derived and analysed in terms of the receptance and decay rate of vibration depending on the possible dimensions of the rail dampers.
3D printing new direction and collaboration in scientific research. A scientometric study using Web of Science, Clarivate Analytics database
Authors: Marinescu (Repanovici) Raluca , Nedelcu Anişor
Published: July 2018

A scientometric study to quantify the global research activity in the field of 3D printing has been conducted by the authors. Primary data was acquired as plain text files from Web of Science database (WoS). 11529 results were found. Hereby, the total research productivity, scientific output of countries, individual institution authors, journals and their collaborative networks were assessed. The results - keywords based on co-occurrence and co-citation networks - were visualized by using VOS Viewer, a software tool for constructing and visualizing bibliometric networks.
Improvement of tools for decision support systems (DSS) in corporate information systems of industrial enterprises
Authors: Plakhin Andrey , Semenets Igor , Ogorodnikova Ekaterina , Mironov Denis
Published: July 2018

Modern industrial enterprises require more qualitative and indepth approaches to the processing of accounting information and its subsequent use in operational activities. The study presents the research results of current situation over the problem that need to be solved by forming and improving the tools for decision support systems. According to the authors of the article, such a toolkit should be an integral part of the corporate information system along with other vital modules.
Standards as a tool for quality management in the pipe market
Authors: Ogorodnikova Ekaterina , Creciun Ludmila , Kokovikhin Alexandr , Dolzhenko Ruslan
Published: July 2018

In the production of large diameter pipes, quality standards are a new tool of struggle in the international market. Management systems that meet the requirements of international standards, for enterprises act as a tool that, in the process of interacting with the external environment, is able to adapt and adequately rebuild the activities of the enterprise. The purpose of the article is to analyze the application of standards in pipe plants as a tool for quality management.
Contributions concerning the possibility of implementing the APQP concept in the aerospace industry
Authors: Pop Alina Bianca , Ţîţu Mihail Aurel , Oprean Constantin , Ceocea Costel , Sandu Andrei Victor , Ţîţu Ştefan
Published: July 2018

To ensure customer satisfaction, the products made by aviation, space and defense organizations need to be continuously improved from the point of view of safety, security, reliability and maintainability. The improvement goal is to be at the customers' requirements and legislations level, if not even to overcome it. The occurring problem with the final products is the challenge to ensure their quality in a shorter time. In this research the importance of implementing the APQP concept in the aeronautical industry is highlighted. To achieve this purpose, the methodologies needed to ensure that the product development processes of the aviation, space and defense industry are fully integrated processes ranging from concept and design to planning, manufacturing and production, aiming the product good use, a quality service and finally getting a positive customer feedback. The final goal of this concept implementing is the Production Part Approval Process (PPAP), which is actually the main result of APQP confirming that the manufacturing process has demonstrated the potential to achieve products that consistently fulfil absolutely all the expressed and not expressed customer requirements.
Energy potential from biomass wastes analysis at the regional level
Authors: Andreenko Tatiana I. , Gabderakhmanova Tatiana S.
Published: July 2018

The paper presents a methodical approach to step-by-step analysis of the agricultural waste resource potential for energy-deficient territories. On an example of model region of Russia (the Volgograd area) the estimation of agroindustrial complex waste energy potential showed that technical potential of waste only in the plant growing of the region is 10 times higher than the consumption of electricity by the rural areas of the region. In addition, the transformation of chemical bonds of crop waste into electrical energy could prevent the release of 1.86 million tons of CO2 per year for the region.
Guidelines on calculation of the concrete thermal treatment modes
Authors: Novikov Sergey , Zhadanovsky Boris , Sinenko Sergey
Published: July 2018

The article provides guidelines on calculation of the cast-inplace reinforced concrete thermal treatment modes: the problem of thermal treatment mode by setting the mathematical temperature field model in the hardening concrete has been solved; model equation which allows calculating the temperature field in the hardening concrete structure using computer software has been solved. These data allow to achieve the high quality of concrete at minimum heat treatment duration and the maximum reduction of energy costs, while minimizing experimental calculations.
Modern technologies of wastewater treatment for low-capacity facilities
Authors: Gogina Elena , Ruzhitskaya Olga , Shmalko Varvara
Published: July 2018

The article touches upon the issues of wastewater treatment on the facilities of small capacity. The brief analysis of the current state is given. The paper reveals main problems to be solved that consider small treatment plant operation, its influence on environment and most prospective solutions. The article considers the developed wastewater treatment technologies, as well as the implementation of these technologies on the patented small plants for deep biological treatment, including with the removal of phosphates at the tertiary treatment stage.
Bioreactor for wastewater treatment
Authors: Kulakov Artem , Makisha Nikolay
Published: July 2018

The article touches upon the efficiency of small capacity wastewater treatment plant for industrial sewage. Current operation scheme fails to meet existing regulation requirements due to several drawbacks. The article describes a technology for wastewater treatment and the construction of bioreactor to implement the scheme above. The technology includes averaging tank with preliminary mechanical treatment and bioreactor with floating feed. This provides the efficiency of removal of organic compounds and nutrients: BOD - 96%, nitrogen - 99%, phosphorus - 89%.
Modern methods for surface wastewater treatment
Authors: Primin Oleg , Varyushina Galina
Published: July 2018

The article gives the characteristics of the system of removal and purification of surface wastewater in Moscow. One of the features of this system is the large-scale use of hydrographic network of the city as elements of the drainage network. Currently improvement of the ecological state of water objects is only possible if to reduce anthropogenic load on them and watersheds, to recover self-cleaning abilities of water bodies and the to protect groundwater from contamination. The article reveals results of research, and contains technological parameters for facilities of surface sewage water purification and recommendations to improve their operation. Article also gives technical solutions to upgrade operated wastewater treatment systems and to ensure the achievement of required standards of treatment of surface runoff when dilution in water. Along with proposals for the reconstruction and construction of wastewater treatment plants with the classical technology of surface water treatment, it is necessary to consider the principle of decentralization with the use of local treatment facilities.
Comparaison du joint de colle entre les attaches préencollées APC™ PLUS et les attaches APC™ Flash-Free
Authors: Jung Aurore , Egloff Benoit , Schweitzer Thierry , Aranda Lionel , Rapin Christophe , Albuisson Eliane , Filleul Marie-Pierryle
Published: July 2018

Introduction : La nouvelle attache préencollée APC™ Flash-Free du groupe 3M Unitek® permet-elle une simplification du protocole de collage sans en diminuer la précision ? Objectifs : L’objectif de cette étude est de comparer la morphologie du joint de colle entre les attaches préencollées classiques APC™PLUS et les attaches APC™ Flash-Free. Matériels et méthodes : Le collage in vitro des attaches esthétiques de la gamme CLARITY™ ADVANCED permet de comparer la morphologie des excès de colle entre les attaches APC™ PLUS et APC™ Flash-Free. Résultats : Aucune différence statistiquement significative concernant la morphologie des excès de colle n’est constatée entre les attaches APC™ PLUS et APC™ Flash-Free. Une différence statistiquement significative concernant l’épaisseur de colle existe entre les deux types d’attaches. L’épaisseur de colle au niveau des attaches APC™ Flash-Free est significativement plus importante que l’épaisseur au niveau des attaches APC™ PLUS (P=0,0001). L’épaisseur de colle est également plus homogène au niveau des attaches APC™ Flash-Free (P=0,001 pour la différence relative). Conclusion : L’épaisseur de colle au niveau des attaches APC™ Flash-Free est plus importante mais plus homogène qu’au niveau des attaches APC™ PLUS.
Immunization with plasmid DNA expressing Heat Shock Protein 40 confers prophylactic protection against chronicToxoplasma gondiiinfection in Kunming mice
Authors: Li Zhong-Yuan , Lu Jing , Zhang Nian-Zhang , Elsheikha Hany M. , Hou Jun-Ling , Guo Hai-Ting , Zhu Xing-Quan
Published: July 2018

Toxoplasma gondiicauses one of the most common protozoal diseases of humans and animals worldwide. With the aim of designing an effective vaccine againstT. gondiiinfection, we examined the immunogenicity of a DNA vaccine expressing heat shock protein 40 (HSP40) against challenge withT. gondii(type I RH and type II Pru) strains in Kunming mice. The plasmid pVAX1-HSP40 was constructed and used to immunize mice by intramuscular injection for three sequential immunizations with two-week intervals. This immunization regimen significantly reduced parasite cyst burden in pVAX1-HSP40-immunized mice (1871.9 ± 142.3) compared with control mouse groups immunized with pVAX1 (3479.2 ± 204.4), phosphate buffered saline (3024.4 ± 212.8), or left untreated (3275.0 ± 179.8) as healthy controls (p < 0.01). However, immunization failed to protect mice against challenge with the virulent RH strain. There was a significant increase in T lymphocyte subclasses (CD3e+CD4+T and CD3e+CD8a+T lymphocytes) in splenic tissues in immunized mice compared with controls (p < 0.05). However, the level of antibodies, lymphocyte proliferation and concentration of cytokines (IFN-γ, IL-2, IL-4, IL-10 and IL-12p70) were not significantly different between immunized and control mouse groups (p < 0.05). These data indicate that pVAX1-HSP40 induced specific immune responses and achieved a significant reduction in the number of brain cysts in Pru-infected mice, and thus can be tested in future immunization studies along with plasmids containing other immunogenic proteins as a cocktail vaccine to fully abolish chronic toxoplasmosis.
Im Schatten der Eltern
Authors: Rothenburg Andrea
Published: July 2018

Psychiatrisch Pflegende kommen auch mit Angehörigen in Kontakt, doch wenn es um Kinder psychisch kranker Eltern geht, entstehen oft Unsicherheiten: Wie verhalte
ich mich? Kann ich die Kinder direkt ansprechen oder kann ich etwas falsch machen? Soll ich lieber an ihnen vorbeischauen, denn ich habe doch nicht gelernt, mit
ihnen umzugehen? Unsere Autorin erläutert anhand ihrer Erfahrungen mit Kindern psychisch kranker Eltern, wie wichtig es ist, nicht wegzugucken, sondern sich dem
Thema zu widmen. Sie nutzt als Projektbeauftragte in einer Psychiatrischen Klinik auch das Medium Film und macht Mut, hinzuschauen und Kinder in schwierigen
Situationen zu unterstützen.
Orte unbegreiflicher Unmenschlichkeit
Authors: Sedetzki Maria , Rungg Christine , Perkhofer Susanne
Published: July 2018

Ergänzend zu ihrem Bericht in der letzten Ausgabe – über die Verwahrung und Tötung von psychisch kranken und behinderten Menschen im Nationalsozialismus – schildern die Autorinnen die Gräueltaten in der Tötungsanstalt Hartheim bei Linz und beschäftigen sich mit der wilden Euthanasie sowie der Rolle der Pflege in der NS-Zeit.
Kommunale Krankenhäuser und die Wirtschaftlichkeit: Der Wert der Leistung
Authors: Dernedde Jutta
Published: July 2018

Wer Leistung bringt, steht in unserer Gesellschaft zunehmend unter dem Druck, sie ständig steigern zu müssen – egal in welchem gesellschaftlichen oder wirtschaftlichen Bereich. Wer auf seinem Leistungsniveau nur stehen bleibt, hat gefühlt schon einen Rückschritt gemacht. Der wahre Wert der Leistung, die jeder und jede Einzelne täglich erbringt, kommt da oft etwas kurz.
Gesetzentwurf für mehr Personal in der Pflege: Kassen befürchten „Leerkauf der Altenpflege“
Authors: Doelfs Guntram
Published: July 2018

Jede zusätzliche Pflegestelle in Kliniken soll ab 2019 vollständig von den Kassen refinanziert werden. Das geht aus dem Entwurf des Pflegepersonal-Stärkungs-Gesetzes hervor, den Bundesgesundheits-minister Jens Spahn (CDU) vorgelegt hat. Während die DKG die Pläne begrüßt, kommt scharfe Kritik von den Kassen. Sie warnen vor einem Rückfall in die Selbstkostendeckung.
Interview mit Frans van Houten: Weg vom Silodenken
Authors: Kucera Martin
Published: July 2018

Philips hat sich den Wandel von einem reinen Produktentwickler zum Lösungsanbieter auf die Fahnen geschrieben. Was das für Klinikkunden bedeutet, erläutert Konzernchef Frans van Houten im Gespräch mit kma am Beispiel der Innovationspartnerschaft mit dem Städtischen Klinikum München.
Interview mit Alexander Schmidtke: Führungswechsel bei Regiomed
Authors: Freye Carolin
Published: July 2018

Im Mai wurde bekannt, dass Joachim Bovelet, Hauptgeschäftsführer des Regiomed-Konzerns seinen Dienstvertrag frühzeitig beenden wird. Sein Nachfolger wird Alexander Schmidtke, derzeit Vorstandsvorsitzender des Klinikums Augsburg – er wird voraussichtlich Anfang 2020 Bovelets Posten übernehmen.
Mitarbeiterbindung: Attraktiver Arbeitgeber Krankenhaus – eine Illusion?
Authors: van Loo Michael , Ute Düvelius
Published: July 2018

Das Personalmanagement stellt Kliniken mehr denn je vor große Herausforderungen. Erklärtes Hauptziel ist es, sich als attraktiver Arbeitgeber zu präsentieren. Mit dem Konzept „UKE INside“ geht die Uniklinik Hamburg Eppendorf dabei einen ganz eigenen Weg.
Fundraising: „Jeder Großspender fängt einmal klein an“
Authors: Mau Jens
Published: July 2018

Kliniken nehmen immer mehr Geld durch Spenden ein. Belastbare Studien zu dem Thema gibt es jedoch nicht. Jetzt befragen mehrere Unikliniken ihre Spender und warten gespannt auf das Ergebnis. kma sprach mit Karl-Heinz Jöckel und Jorit Ness, den Initiatoren der Studie.
Strafrechtliche Risiken im Krankenhaussektor: Die Tücke liegt im Detail
Authors: Martenstein Ines , Wohlgemuth Martin
Published: July 2018

Vor knapp zwei Jahren trat das Gesetz zur Bekämpfung von Korruption im Gesundheitswesen in Kraft. Anhand von drei exemplarisch ausgewählten Konstellationen zeigen wir auf, welche strafrechtlichen Risiken bei der Vertragsgestaltung zu bedenken sind – und geben Hinweise, wie im Fall eines Ermittlungsverfahrens agiert werden kann.
Hygiene im Krankenhaus: Kampf gegen die Keime
Authors: Mewis Dirk
Published: July 2018

Wenn man in ein Krankenhaus eingeliefert wird, fürchtet man zwei Dinge: Komplikationen und Infektionen. Denn die Gefahr, sich im Krankenhaus mit einem Erreger anzustecken, ist real.
Integrierte Versorgung ist Brennpunkt in der Gesundheitspolitik: Große Erwartungen und gewachsene Ansprüche
Authors: Spitzer Stefan G.
Published: July 2018

„Der Kernbereich der Gesundheitspolitik in der kommenden Legislaturperiode ist die sektorenübergreifende Versorgung”, das erklärte bereits im November 2017 Prof. Wolfgang Greiner, Mitglied des Sachverständigenrates zur Begutachtung der Entwicklung im Gesundheitswesen. Wie zur Bestätigung dessen beschäftigt sich auch das Jahresgutachten 2018 des SVR Gesundheit unter anderm mit diesem Thema.
pH-Driven Conformational Switching of Quinoxaline Cavitands in Polymer Matrices
Authors: Dalcanale E. , Torelli M. , Domenichelli I. , Pedrini A. , Guagnini F. , Pinalli R. , Terenziani F. , Artoni F. , Brighenti R.
Published: July 2018

While pH-driven interconversion of tetraquinoxaline cavitands (QxCav) from vase to kite conformation has been extensively studied both in solution and at interfaces, cavitands behavior in solid matrices is still unexplored. Therefore, the synthesis of a new class of quinoxaline cavitand based copolymers is here reported; a soluble linear poly(butyl methacrylate) (PBMA) and an insoluble cross-linked polydimethylsiloxane (PDMS), ensuring a convenient incorporation of the switchable unit, were chosen as polymer matrices. Conformational studies, performed both in solution and at the solid state, confirmed the retention of vase → kite switching behavior when moving from monomeric units to polymeric structures.
Uso de pruebas genómicas en tejido prostático, en el seguimiento de los pacientes con cáncer de próstata en protocolo de vigilancia activa: Revisión sistemática de la literatura
Authors: Gómez Meza Jorge , Lizcano Ana , Solano Liz , Riatiga Diego , Rojas Daniel , García Juan
Published: July 2018

Introducción y objetivos La vigilancia activa es una estrategia que busca diferir tratamientos con intención curativa y la morbilidad derivada de los mismos. Actualmente se requieren estrategias de seguimiento con mayor potencial de predicción en la enfermedad que permitan determinar de manera adecuada los pacientes candidatos para vigilancia activa. El objetivo de este estudio es realizar una revisión sistemática de la literatura sobre las pruebas genómicas en tejido prostático de los pacientes con cáncer de próstata en protocolo de vigilancia activa.

Materiales y métodos Se realizó una revisión sistemática de la literatura basados en criterios de inclusión y exclusión, en las bases de datos Pubmed, Scopus, Embase y Cochrane, para pruebas genómicas en tejido prostático de los pacientes con cáncer de próstata en vigilancia activa, basados en el modelo PRISMA.

Resultados Los estudios incluidos tuvieron en cuenta los siguientes desenlaces: Progresión de la enfermedad, mortalidad cáncer específica, Gleason >4 y hallazgos adversos en la biopsia confirmatoria. Las pruebas más utilizadas fueron el TMPRSS2: ERG, alelos para riesgo de cáncer de próstata y polimorfismos simples de nucleótidos. Se encontró el ERG–2 como factor predictor de progresión de enfermedad. Para los polimorfismos simples de nucleótidos, la evidencia no mostró correlación con el hallazgo de Gleason >4, tiempo a tratamiento ni para hallazgos adversos en la biopsia confirmatoria, sin embargo, esos estudios fueron de carácter retrospectivo. Por el contrario, en otro estudio, se encontró un área bajo la curva de 0,66 para polimorfismos simples de nucleótidos lo que sugiere que ellos pueden discriminar entre un resultado favorable y desfavorable en la patología del espécimen. En cuanto a los alelos asociados al riesgo de características adversas en la patología, se encontró una asociación estadísticamente significativa y un aumento de dos veces mayor riesgo en aquellos pacientes que tuvieran la expresión de al menos 3 de esos alelos. Ninguna de las pruebas utilizadas en los diferentes estudios permitió tomar la decisión de continuar o suspender el protocolo de vigilancia activa.

Conclusión Los estudios sobre pruebas genómicas en tejido prostático de los pacientes con cáncer de próstata en vigilancia activa son escasos y con bajo poder estadístico, algunos de ellos sugieren la capacidad discriminatoria entre características favorables y desfavorables en la patología, sin embargo, esos resultados aún son controversiales y con poca validez interna. Se requieren de estudios prospectivos que permitan determinar el rol actual en el manejo de esos pacientes.
Effects of Sulfated Polysaccharides on Inhibition of Thrombus Formation initiated by Different Stimuli
Authors: Ryn-McKenna J Van , Gray E , Weber E , Ofosu F A , Buchanan M R
Published: July 2018

To test the possibility that different doses of heparin or other sulfated polysaccharides are required to inhibit thrombosis initiated by different stimuli, we compared the effects of heparin (HEP), pentosan polysulfate (SP54) and dermatan sulfate (DS) on the inhibition of thrombus formation induced by either I) tissue thromboplastin; II) thrombin; or III) factor Xa. Inhibition of thrombus formation induced by the stimuli was measured in a rabbit jugular vein hypercoagulation/stasis model. First, we determined the minimum dose of each sulfated polysaccharide which inhibited tissue thromboplastin-induced thrombus formation by ∼75%, and then compared the relative effectiveness of this dose to prevent thrombus formation initiated with the other two stimuli. HEP and SP54 were less effective when thrombin was the thrombogenic stimulus, while DS was more effective. HEP was the most effective agent when factor Xa was the stimulus. We conclude that the antithrombotic effectiveness of a given dose of a sulfated polysaccharide may vary depending on the stimulus which initiates thrombus formation.
ARICHemostasis Study - I. Development of a Blood Collection and Processing System Suitable for Multicenter Hemostatic Studies
Authors: Papp A C , Hatzakis H , Bracey A , Wu K K
Published: July 2018

In order to carry out a multicenter study aimed at understanding the association of hemostatic factors with atherosclerotic vascular disorders for the Atherosclerosis Risk In Communities (ARIC) Study, we compared a blood collection and processing system developed in our laboratory with the state-of-the-art- procedures. The salient features of our system included the use of a new phlebotomy set for venipuncture, the use of Millipore filters for removing platelet residues in the plasma and the use of a mixture of anticoagulants and antiplatelet agents for inhibiting the in vitro activation of platelets, coagulation and fibrinolytic system. The results derived from systematic evaluations indicate that this newly developed system yields the lowest values of plasma ßTG, PF 4 and FPA when compared with the reported values. The technique also gave reliable values of representative hemostatic measurements such as fibrinogen, factor VII, factor VIII, von Willebrand factor, antithrombin-III, protein C, tissue- type plasminogen activator, and serum thromboxane B2. Further experiments revealed that the samples withstood temporary storage at −70° C and overnight “shipping” manipulations without significant changes in the hemostatic values. We conclude that the described blood collection and processing system may be a valuable asset for conducting multicenter cooperative clinical trials and epidemiologic studies involving blood collection by multiple field centers or clinics.
Absence of Potentiation with Murine Antiplatelet GPIIb/IIIa Antibody of Thrombolysis with Recombinant Tissue-Type Plasminogen Activator (rt-PA) in a Canine Venous Thrombosis Model
Authors: Spriggs D , Gold H K , Hashimoto Y , Houtte E Van , Vermylen J , Collen D
Published: July 2018

F(ab’)2 fragments of a murine monoclonal anti-platelet GPIIb/ IIIa antibody (7E3) are a potent platelet aggregation inhibitor, which in a canine coronary artery thrombosis model accelerate lysis with recombinant tissue-type plasminogen activator (rt-PA) and prevent reocclusion (7).

In the present study, we have investigated the potential value of platelet aggregation inhibition as adjunctive therapy to lysis of venous thrombi, by measuring the thrombolytic potency of 7E3- F(ab’)2 and rt-PA used alone or in combination, in dogs with a 125I-fibrin labeled femoral vein thrombus. The dose-response of thrombolysis with rt-PA infused over 4 hours was linear: doses of 0.075 mg/kg, 0.15 mg/kg and 0.3 mg/kg produced 37 ± 3, 57 ± 11 and 83 ± 4% lysis respectively, against a background value of 20 ± 2%. With F(ab’)2 fragments of 7E3 given as a bolus of 1.2 mg/ kg, which saturated 70% of the platelet GPIIb/IIIa receptors and prolonged the bleeding to more than 30 min, lysis was not significantly increased over background. Combination of 0.3 or 0.6 mg/kg of 7E3-F(ab’)2 with either 0.03 or 0.06 mg/kg of rt-PA did not produce more lysis than obtained with a comparable dose of rt-PA alone. No significant changes in plasma fibrinogen or α2- antiplasmin were observed with either agent alone or with the combination. It is concluded that extensive inhibition of platelet aggregation does not potentiate the thrombolytic effect of rt-PA in this venous thrombosis model.
Significance of Plasma Adenosine in the Antiplatelet Activity of Forskolin: Potentiation by Dipyridamole and Dilazep
Authors: Agarwal Kailash C , Zielinski Beth A , Maitra Ranjan S
Published: July 2018

Forskolin, a plant (Coleus forskohlii) diterpene, inhibits ADP- induced (human: IC50, 2.3±1.0 μ;M; rat: IC50, 1.2±0.5 μM) and collagen-induced (human: IC50, 2.4±1.2 μM; rat: 0.6±0.2 μM) platelet aggregation in human and rat platelet-rich plasma (PRP). Human blood levels of adenosine (Ado) are low (100-300 nM) as compared to levels in rat plasma (7.55 ± 0.51 μM). Ado is a natural antiplatelet and vasodilatory agent produced by vascular endothelium, heart and other body tissues. If the plasma Ado is degraded by pretreatment of PRP with adenosine deaminase (ADA), forskolin inhibition on platelet aggregation is reduced by 2-4 fold both in human and rat blood. On the other hand, if the physiological steady state levels of Ado are maintained by collecting the blood in the presence of the inhibitors of ADA (2’-deoxycoformycin, dCF, 5 μM) and Ado uptake (dipyridamole, 10 μM or dilazep, 2 μM), forskolin inhibition (IC50, 3.2 μM) on platelet aggregation in human PRP is potentiated by 20-40 fold (IC50, 0.075-0.15 μM). Similar potentiated forskolin effect (IC50, 0.53 μM) is seen if the ADA-treated human PRP is replenished with a low level of Ado (50 nM) after ADA inactivation by dCF and Ado-uptake blockade by dilazep. If the plasma is replenished with a higher concentration of Ado (300 nM), greater potentiation is seen (IC50, 0.23 μM). Forskolin is 2-4 fold more inhibitory in rat PRP than in human PRP, partially due to the presence of higher levels of Ado in the rat plasma. These studies demonstrate an important role of plasma Ado in the antiplatelet activity of forskolin and this effect can be greatly potentiated by the clinically used drugs, dipyridamole and dilazep.
Differing Susceptibilities of Platelets from Normal Individuals and Patients with von Willebrand’s Disease to Attack by Quinine- and Quinidine-Dependent Antiplatelet Antibodies
Authors: Pfueller Sharron L , Bilston Robyn A , Logan Dana , David Rosemary , Sloan Ian G , Firkin Barry G
Published: July 2018

Reactivity of quinine- and quinidine-dependent antiplatelet antibodies has been compared in platelet-rich-plasma (PRP) from normal donors and from patients with von Willebrand’s disease (vWd). One quinine-dependent antibody (Q. Ab) caused platelet aggregation and [14C] serotonin release with only 7 of 12 normal donors, while another Q. Ab and a quinidine-dependent antibody (Qd. Ab) caused aggregation and release with all 12. Drug- dependent IgG binding and PF 3 availability induced by the antibodies were, however, comparable in all donors. Differences in responsiveness were associated with platelets and not plasma. vWd platelets showed normal drug-dependent IgG binding, but decreased aggregation and serotonin release to most drug- dependent antibodies. Responsiveness was not restored by purified vWf:Ag, but, in one case, was corrected by normal plasma or cryoprecipitate. Drug-dependent binding of the Q. Ab which caused variable responsiveness in normals was to the same platelet antigens (GPIb and GPIIIa) in both normal and vWd platelets and did not require plasma components. Reduced PF 3 availability was seen with some antibodies in some vWd patients. Plasma from two of these patients inhibited aggregation of normal platelets to Q. Ab and one of these inhibited aggregation to ADP. Antiplatelet antibodies were detected in these two plasmas by ELISA. Thus some Q. Ab produce different responses with platelets from different donors. In vWd, reduced responsiveness to Q.Ab and Qd. Ab may result from production of inhibitory antiplatelet antibodies.
Binding of Tissue Plasminogen Activator to Vascular Grafts
Authors: Harvey Richard A , Kim Hugh C , Pincus Jonathan , Trooskin Stanley Z , Wilcox Josiah N , Greco Ralph S
Published: July 2018

Tissue plasminogen activator labeled with radioactive iodine (125I-tPA) was immobilized on vascular prostheses chemically modified with a thin coating of water-insoluble surfactant, tridodecylmethylammonium chloride (TDM AC). Surfactant- treated Dacron, polytetrafluoroethylene (PTFE), silastic, polyethylene and polyurethane bound appreciable amounts of 125I- tPA (5-30 μg 125I-tPA/cm2). Upon exposure to human plasma, the amount of 125I-tPA bound to the surface shows an initial drop during the first hour of incubation, followed by a slower, roughly exponential release with a t½ of appoximately 75 hours. Prostheses containing bound tPA show fibrinolytic activity as measured both by lysis of clots formed in vitro, and by hydrolysis of a synthetic polypeptide substrate. Prior to incubation in plasma, tPA bound to a polymer surface has an enzymic activity similar, if not identical to that of the native enzyme in buffered solution. However, exposure to plasma causes a decrease in the fibrinolytic activity of both bound tPA and enzyme released from the surface of the polymer. These data demonstrate that surfactant-treated prostheses can bind tPA, and that these chemically modified devices can act as a slow-release drug delivery system with the potential for reducing prosthesis-induced thromboembolism.
A Double-Blind Randomized Placebo Controlled Trial of Thromboprophylaxis in Major Elective General Surgery Using Once Daily Injections of a Low Molecular Weight Heparin Fragment (Fragmin)
Authors: Ockelford Paul A , Patterson Janet , Johns Allan S
Published: July 2018

The safety and efficacy of the low molecular weight heparin fragment (Fragmin) administered as a single daily injection of 2,500 anti Xa units has been evaluated in 183 patients undergoing major elective general surgery. The study was double-blinded and placebo controlled. The active agent, or placebo, was given subcutaneously with the preoperative medication and continued postoperatively for 5-9 days. Ninety five patients received Fragmin and 88 were randomized to receive the placebo. The clinical characteristics of the two treatment groups were similar. Fragmin significantly reduced the incidence of deep venous thrombosis, as detected by a positive 125I fibrinogen leg scan, relative to the placebo treated patients (4/95, 4.2%; v. 14/88, 15.9%; p = 0.008). The thrombotic events occurred predominantly (73%) amongst patients with malignancy. Haemorrhagic endpoints necessitating discontinuation of the trial treatment were 4% in each group. No severe adverse reactions or drug related deaths occurred. These results indicate that 2,500 anti Xa units of Fragmin given only once daily is effective thromboprophylaxis for patients undergoing major elective abdominal surgery.
Thrombin-Antithrombin III Complexes in the Prediction of Deep Vein Thrombosis Following Total Hip Replacement
Authors: Hoek J A , Nurmohamed M T , ten Cate J W , Büller H R , Knipscheer H C , Hamelynck K J , Marti R K , Sturk A
Published: July 2018

In 196 consecutive patients who underwent elective total hip surgery we investigated the diagnostic accuracy of the thrombinantithrombin III complex immunoassay, as assessed on the first, fourth and tenth postoperative day, for the development of deep vein thrombosis (DVT). Patients received either LMWheparinoid (n = 97) or placebo (n = 99) and underwent contrast venography on the tenth postoperative day.

Thrombin-antithrombin III (T-AT) plasma levels were raised in all patients on the first postoperative day and gradually decreased during the study period. T-AT plasma levels were significantly higher in patients developing DVT when compared to patients without DVT and remained so until day 10. This difference was apparent both in the LMW-heparinoid group as well as in the placebo-treated patients.

ROC-curve analysis revealed no satisfactory discriminative power for the diagnosis of developing DVT at any of the studied cut-off values for T-AT.

We conclude that the postoperative determination of T-AT complex plasma concentrations in hip surgery patients has no clinical utility in the prediction of postoperative DVT.
Gold-Labeled Bovine Fibrinogen for Study of Human Platelets
Authors: Grouse Lynette H , White James G
Published: July 2018

Fibrinogen coupled to colloidal gold has proven to be a useful agent for probing the glycoprotein IIb-IIIa receptor on human and bovine platelets at the ultrastructural level. The reagent has helped to demonstrate fundamental differences in the reorganization of the fibrinogen receptors on human and cattle platelets following surface activation. However, commercial preparations of human fibrinogen have not yielded a stable reagent in our hands when coupled to colloidal gold. The present study has substituted bovine for human fibrinogen. Bovine fibrinogen gold proved to be a more stable reagent and could be substituted for human fibrinogen gold in all experiments on human and bovine platelets.
The Prediction of Post-operative Deep Vein Thrombosis, Using a Newly Described Test of Platelet Function
Authors: King J. B , Joffe S. N
Published: July 2018

Using a newly described test of platelet function which measured the ability of platelets washed free of plasma to generate thrombin in vitro, a study was made of patients undergoing surgery. Samples of platelets were taken before and immediately after operation in 27 cases. In 10 cases there was a significant increase in thromboplastin generation by these washed platelets, and 8 of these cases developed postoperative deep vein thrombosis. In a further 17 cases both pre- and post-operative tests were within the normal range, and only 2 of these cases developed deep vein thrombosis. It is thought that this test makes use to a significant degree of the throm- boplastic properties of the platelet surface, and it is suggested that alteration in these surface properties during operation may be, to some extent, responsible for the deep vein thrombosis in the post-operative period.
Renal Cortical Fibrinolytic Activity in the Rabbit Following One or Two Doses of Endotoxin
Authors: Bergstein Jerry M. , Michael Alfred F.
Published: July 2018

A fibrin slide technique has been utilized to study the effect of endotoxin on renal cortical fibrinolytic activity in the rabbit. Lytic activity was absent in kidney tissue obtained from animals given one injection of endotoxin and after development of the generalized Shwartzman reaction. Cortical lytic activity was not inhibited following in vitro incubation of tissue sections in phosphate-buffered saline solutions containing high concentrations of endotoxin.

It is suggested that the initial injection of endotoxin may prepare for the generalized Shwartzman reaction by depletion of cortical fibrinolytic activity. The failure of endotoxin to inhibit tissue plasminogen activator in vitro suggests that endotoxin-induced loss of lytic activity is mediated through humoral factors.
Quantitation of Fibrin Deposition and Elimination in Organs of Rats Injected with Labelled Fibrinogen by Isolation of the Labelled Fibrin from Water Soluble Tracer
Authors: Busch Christer , Rammer Lennart
Published: July 2018

A method for direct quantitation of fibrin in organs after intravascular coagulation in rats injected with labelled fibrinogen is described. After homogenization and centrifugation of the tissue the fibrin can be measured in the pellet, while the water soluble tracer largely remains in the supernatant.
In Vitro Effects of Lipids on Fibrinolysis
Authors: Chopin Suzzette F. , Beard E Letitia
Published: July 2018

The effect of suspensions of corn oil, butter, cholesterol, and beta lipoprotein in concentrations in the range of normal blood lipid levels on the ability of lytic agents to digest fibrin clots in vitro has been examined. In one assay, the lipid solutions were incubated with streptokinase, plasminogen activator or plasmin prior to addition of the lytic agent to the clot and its fibrinolytic activity was then assessed. Secondly, the lipids were incorporated into the clots and the three lytic agents were added directly. The lipids used markedly inhibited the lytic effect of plasminogen activator (34% mean) and plasmin (28.9% mean) when they were allowed to interact in solution prior to addition to the clot. Streptokinase was significantly inhibited in this manner but to a much smaller degree (7% mean). Lipids incorporated within the clots actually enhanced the lytic action of plasminogen activator (8.8% mean), mildly inhibited clot dissolution by plasmin (5.9%) and insignificantly altered the action of streptokinase. The effects of the lipids used appeared to be relatively nonspecific.
The Phase II Urokinase-Streptokinase Pulmonary Embolism Trial
Authors: Sasahara Arthur A , Bell William R , Simon Toby L , Stengle James M , Sherry Sol
Published: July 2018

The controlled clinical trials of thrombolytic agents in the United States have been carried out in two phases, under the auspices of the National Heart and Lung Institute. Phase I was devoted to the comparison of 12-hour Urokinase (12h–UK) followed by heparin (H) with heparin alone in patients with acute pulmonary embolism (Walsh et al. 1969). The results showed that patients treated with UK had more rapid and greater resolution of pulmonary thromboemboli in the first twenty-four hours of therapy than patients treated with H alone, as assessed by serial pulmonary angiography, hemodynamics and lung scanning (The Urokinase Pulmonary Embolism Trial, 1970, 1973 ; Hyers et al. 1970). Because of the relatively small size of the Trial and the low mortality of treated pulmonary embolism, mortality differences were not sought - nor was one found. Although there was early difference in amount of clot resolution, patients treated with H alone showed similar improvement by two weeks.

The Phase II Urokinase-Streptokinase Pulmonary Embolism Trial (USPET) was begun to assess the comparative results of UK and Streptokinase (SK) therapy. Because of favorable results obtained with SK in other countries, it was deemed necessary to make this comparison (Browse and James, 1964 ; Hirsh et al. 1968 ; Miller et al. 1969, 1971 ; Chesterman et al. 1969). A third group, 12-hour UK, was added to relate this study (24-hour UK and SK) with the Phase I results which employed only a 12-hour infusion of UK. This Phase II Trial represents the first controlled, randomized study of UK and SK in thromboembolic disorders.
Enhancement of ADP-Induced Platelet Aggregation by Cholesterol and Its Prevention by Pyridinolcarbamate
Authors: Sano Tadahiro , Yamazaki Hiroh , Shimamoto Takio
Published: July 2018

The authors reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of cholesterol in rabbits. In such circumstances, platelet aggregability to ADP was examined by 2 methods: 1. measurement of intensity of platelet aggregation induced by ADP using the optical density method and 2. determination of minimum concentration of ADP solution to induce platelet aggregation using a light microscope. Three hours after oral administration of 1 g/kg of cholesterol, the intensity of aggregation in 12 rabbits increased to 106.0 ±2.4% (mean ± S. E.) by 10 ìM, 108.5 ±2.6% by 3 ìM and 110.2 ±3.7% of the value before the administration by 1 ìM of ADP. The differences were statistically significant (P <0.05). At that time, platelet in CPRP collected after cholesterol intake were aggregated by eight-times diluted ADP solution compared to that collected before cholesterol administration in 2 rabbits, four-times in 4 and two-times in 3 among 10 cases. Pyridinolcarbamate, which showed preventive effect against appearance of edematous changes in aortic wall induced by cholesterol and/or adrenaline, prevented these phenomena, when it was given 10 mg/kg orally 3 hours prior to cholesterol administration.
Detection of Platelet Desensitization in Pregnancy-Induced Hypertension Is Dependent on the Agonist Used
Authors: Ahmed Y , Sullivan M H F , Elder M G
Published: July 2018

The aggregation of platelets from women with pregnancy-induced hypertension (P.I.H.), or with normal pregnancies, in response to arachidonic acid, ADP, collagen or platelet activating factor (PAF) was examined. No differences in platelet aggregation between the normotensive and hypertensive women were detected when arachidonic acid or collagen were used to stimulate in vitro platelet aggregation. Higher concentrations of ADP and PAF were required to aggregate platelets from women with P.I.H. compared with platelets from normotensive controls. Platelets from women with normotensive pregnancies (n = 80) aggregated maximally in response to 20 nM PAF without exception. Reversible aggregation by platelets from women with P.I.H. (n = 25) was observed at the same concentration of PAF; again, this was found in all subjects tested. These results indicate that PAF at a concentration of 20 nM can clearly demonstrate differences in aggregation of platelets from women with normotensive pregnancy and women with P.I.H.
Acquired Disorder of Platelet Function Associated with Autoantibodies against Membrane Glycoprotein IIb-IIIa Complex - 1. Glycoprotein Analysis
Authors: Meyer M , Kirchmaier C M , Schirmer A , Spangenberg P , Ströhl Ch , Breddin K
Published: July 2018

A patient with idiopathic thrombocytopenic purpura developed after splenectomy a thrombasthenia-like severe haemor-rhagic diathesis characterized by a normal or subnormal platelet count, prolonged bleeding time, strongly reduced platelet adhesion to glass and defective platelet aggregation in response to ADP and collagen. In contrast to hereditary thrombasthenia membrane glycoproteins (GP) lib and Ilia were normally present in the patient’s platelets. Immunoelectrophoretic analysis revealed an abnormal behaviour of the patient’s GP IIb-IIIa complex. Autoantibodies against GP IIb-IIIa were detected in Triton-extracted washed platelets. Incubation of normal platelets with plasma from the patient resulted in a similar immunoelectrophoretic abnormality of the GP IIb-IIIa complex indicating that bound autoantibodies (IgG) are responsible for the abnormal immunoelectrophoretic behaviour of the patient’s GP IIb-IIIa complex. Platelet fibrinogen was severely reduced similar to classical thrombasthenia suggesting that the GP IIb-IIIa complex is involved in platelet fibrinogen storage.