bluuebunny/crossref_metadata_2025_split huggingface dataset:
STUDY ON THE EFFECT OF UNFRACTIONATED (UFH) AND LOW MOLECULAR WEIGHT (LMWH) HEPARINS ON THE DETERMINATION OF PROTEIN C ACTIVITY
Authors: Sala N , Fontcuberta J 
Published: June 2019

In an attempt to see whether the presence of different heparins affected the determination of protein C activity (APC),this parameter was measured before and during treatment in 23 deep vein thrombosis patients that had been randomly treated with 3 different LMWH (Choay CY-216 and CY-222 and Kabi-2165) and UFH,for 10 days, Very low levels of APC (amidolytic assay that uses thrombin-thrombomodulin to activate the barium citrate eluted PC) were found in those patients receiving UFH and having an APTT more than 3 times that of control, as well as in those patients receiving LMWH CY-216 and having an APTT of only 8 to 10 seconds higher than that of control plasma, In patients receiving CY-222 and Kabi-2165, no significant differences were observed between APC levels before and during treatment, PC antigen (ELISA assay) was normal in all cases, In order to see if these low APC levels were due to interference of heparin with the assay and at which doses, control plasma pool was supplemented "in vitro" with 0 to 2.5 IU/ml (0 to 0,00252) of UFH and with 0 to 3 anti-Xa U/ml of LMWH CY-216, APTT, PCAg, APC and presence of ATI 11 in the barium citrate eluates (immunodiffusion), were determined in all plasma samples before and after treatment with protamine sulphate (PS) at 0,0032, The results showed that UFH, when not neutralized with PS, resulted in low APC values only at doses higher than 0,8 IU/ml, corresponding to an APTT of more than 3 times that of control plasma, LMWH CY-216 at doses above 1 anti-XaU/ml, corresponding to an APTT of only 10 seconds higher than that of control, also produced a gradual decrease in APC values, ATI 11 was clearly visualized in the barium citrate eluates of all those plasma samples having a low APC value, The addition of PS to all samples containing UFH resulted in a complete normalization of APC values, with almost normal AFTT values and disappearance of ATI 11 from the barium citrate eluates, On the contrary, addition of PS to plasma containing CY-216 resulted in low APC values and presence of ATI 11 in the eluates of those samples containing more than 4 antiXaU/ml, whose APTT still was about 10 seconds above that of control.It is concluded that at therapeutic doses not only UFH but also LMWH CY-216 interfere with the APC assay, probably through binding of hepar in-ATI 11 complexes to barium citrate and neutralization of the thrombin used to activate the barium citrate eluted PC, LMWH CY-222 and Kabi-2165, although increasing the APTT similarly to CY-216, do not seem to interfere with the APC assay, Protamine sulphate, at 0,0032 in plasma, completely abolishes the effect of UFH on APC assay but not that of LMWH CY-216, More studies are being performed to see if higher doses of PS can be used to neutralize the effect of this LMWH.
Effects of Denture Base Thicknesses and Reinforcement on Fracture Strength in Mandibular Implant Overdenture with Bar Attachment: Under Various Acrylic Resin Types
Authors: Tokgoz Selen , Ozdiler Arda , Gencel Burc , Bozdag Ergun , Isık-Ozkol Gulbahar 
Published: June 2019

Abstract
Objective This study aimed to assess the effect of reinforcement, denture base thickness, and acrylic resin types on dynamic and static fracture strength in mandibular implant overdentures with bar attachment.
Materials and Methods One hundred and eight experimental mandibular implant overdentures with bar attachments were fabricated in three main groups, namely unreinforced (control: C), reinforced with unidirectional glass fibers (FR), and Co–Cr cast metal (MR). Each group included denture bases of 2-, 3-, and 4-mm thicknesses and produced with conventional (CA) and high-impact acrylic (HIA) resins. Specimens were thermocycled (5,000 times, 5–55°C) then subjected to a 400,000 cyclic load regime. Unbroken specimens were then loaded until fracture by a universal testing machine. Differences in mean fracture resistance among the groups were compared using the one-way analysis of variance (with post hoc Tukey's honestly significant difference test) and Student's t-tests (α = 0.05).
Results Fracture strength increased significantly when the denture base thickness was increased (p = 0.001). The 2-mm denture base thickness was not enough for reinforcement. The fracture strength of the FR groups was significantly higher than other groups for 3- and 4-mm thicknesses (p = 0.001). The fracture strength of the HIA resin was significantly higher than CA resin in FR groups (p = 0.029 and p = 0.001). MR groups showed the weakest fracture strength.
Conclusions The 2-mm denture base thickness had sufficient fracture strength without reinforcement and a positive relationship between acrylic resin thickness and fracture resistance was found.
Morphological Assessment of Maxillary Sinus Septa Variations with Cone-Beam Computed Tomography in a Turkish Population
Authors: Kocak Nazan , Alpoz Esin , Boyacıoglu Hayal 
Published: June 2019

Abstract
Objective The purpose of this study was to measure and classify sinus septa variables (prevalence, numbers, heights, locations, orientations, and morphology) and to determine the effects of age, gender, and dental status on the presence of septa and also to evaluate the effects of septa on pathological mucosal thickening.
Materials and Methods A total of 2,000 patients were analyzed through conebeam computed tomography (CBCT). The total of 500 maxillary sinuses were included in this study. The number of maxillary sinus septa was determined on axial sections of CBCT images. Their locations, orientations, and morphologies were determined on both the axial and sagittal sections, and their heights were determined only on the sagittal sections. The influence of age, gender, dental status, and pathological mucosal thickening on the presence of septa was statistically analyzed. Mann–Whitney U-test and descriptive statistics were used for statistical analysis.
Results The average height of the determined 287 septa was measured as 7.36 mm. The highest rates of septa location, morphology, and orientation were found, respectively, in the middle region septa (57.49%), completed septa (75.95%), and transverse septa (93.37%). The effect of dental status, age, and gender on the presence of septa was not statistically significant (p > 0.05).
Conclusion These high rates of findings support the importance of CBCT in the diagnosis of the variations of the maxillary sinus septa. Therefore, it is important to evaluate CBCT images of the relevant region to increase the success of surgical interventions in the maxillary posterior region and to eliminate possible complications.
Release of Fibrinolytically Active Compounds During Platelet-UK Interaction
Authors: Koch M. , Binder B. , Auerswald W. 
Published: June 2019

In view of contradictory reports concerning the influence of platelets on the fibrinolytic activity in vivo and in vitro, we studied the effects of washed platelets on the fibrinolytic activity of added urokinase (UK). Different amounts of UK (0.6 to 2.5 CTA units per ml, purified UK-preparation) were mixed with washed platelets numbering 1,000 to 1,000,000,000 per ml. The fibrinolytic activities of these mixtures as well as of the platelet-free supernatants there of were tested on native and heated fibrin plates. Neither UK nor platelets alone nor the mixtures of both revealed any fibrinolytic activity on heated fibrin plates. In addition, no plasminogen activator activity of the native platelets could be detected.The presence of more than 10,000,000 platelets per unit UK suppressed the kinases’s activity progressively as the platelet number increased. With less than 10.000.000 platelets per unit UK the kinase activity was augmented to a maximum when the platelet count reached about 200,000 per unit UK. The supernatants of the platelet-UK mixtures reflected the same activities as the mixtures. Using plasmin instead of UK in the mixtures with platelets similar results were obtained. In control experiments incubating platelets with albumin- or buffer-solutions the supernatants were without effects. Furthermore at no of the mentioned concentrations of UK added to platelets were any effects found on their count, their adherence to glass, and their spreading ability.In preliminary investigations supernatants from platelet-UK mixtures were gel fractionated on Sephadex G-150, to determine the presence of fractions with inhibiting and/or potentiating effects on fibrinolysis. An inhibiting fraction of low mol. wt. and probably two potentiators of higher mol. wt. have thus far been found.Supp. by a Grant of the Austr. Fund f.t. Promot. of Scient. Res. (Proj. Nr. 1800).
A Smaller Molecule SK-Reactive Protein (Plasminogen-Proactivator) Derived from the Macromolecule of Human Plasma Fraction I.
Authors: Okamoto U. , Yamamoto J. 
Published: June 2019

The SK-reactive plasminogen-proactivator reported in detail by previous workers assumed a macromolecule protein though still impure. A smaller molecule proactivator highly purified is described in the present paper.Fraction I of human plasma was chosen as staring material after preliminary studies. The macromolecule obtained by gel filtration had low specific activity of SK-reactive protein (proactivator) but little UK-reactivity, showing constantly a large molecular weight by repeating gel filtration. The successful purification of proactivator was achieved by Lysine-Sepharose affinity chromatography, using as eluant t-AMCHA (fibrinolysis inhibitor) which was found suitable.The proactivator fraction thus obtained showed the high sensitivity to SK, other proteins being removed satisfactorily and the specific activity being increased extremely. Even a trace of plasminogen was not detected. Molecular weight of the proactivator was found 98,000 by gel filtration.The results indicate that the smaller molecule proactivator described is a basic entity of SK-reactive proactivator of plasminogen.
Coagulation Inhibitors Studied with Chromogenic Substrate
Authors: Abildgaard U. , Lie M. , Teien A. , Ødegård O. R. 
Published: June 2019

The rapid amidolysis of the chromogenic substrate Bz-Phe-Val-Arg-pNA by thrombin (Svendsen & al. Thromb. Res. 1, 267, 1972) provides a useful tool for the study of coagulation inhibitors. With purified reagents, reversible inhibition of the reaction can be demonstrated with 0.01 U/ml of heparin. The inactivation of thrombin by antithrombin III (At-III) is accelerated by 0.001 U/ml of heparin, making it possible to assay small amounts of heparin. The amidolytic assay system has also been used to study the competition between thrombin and factor Xa for At-III.The sensitivity and specificity of rapid amidolytic methods for assay of the following plasma activités will be reported:1) At-III activity (contaminating heparin neutralized).2) Exogenous heparin (during heparin treatment).3) Combined effect of At-III and exogenous heparin.4) At-III in the presence of optimal concentrations of heparin.
Affinity of Antithrombin II/III to Insolubilized Heparin
Authors: Thaler E. , Schmer G. 
Published: June 2019

Five heparin fractions of different molecular weight range were obtained from commercial sodium heparin (Sigma) by gel chromatography on Sephadex G-200. Each fraction was bound separately to Biogel A-15 m by the cyanogen bromide reaction. Microcolumns containing equal amounts of the individual heparin agarose batches were prepared. A protein fraction from human plasma containing antithrombin II/III but no fibrinogen, which was obtained by polyethylene glycol precipitation, was passed through the columns. After extensive washing with 0.15 and 0.3 M buffered sodium chloride antithrombin was eluted with 1.0 M buffered sodium chloride. The uptake of antithrombin did not differ greatly in all five heparin agarose preparations. However, the amount of antithrombin eluted with 1.0 M NaCl varied considerably depending on the insolubilized heparin fraction. Almost no antithrombin activity was eluted from the agarose grafted with the highest molecular weight heparin, while all of the antithrombin was recovered from the agarose with the intermediate molecular weight heparin.Our findings of different affinities of antithrombin to insolubilized heparin in dependance of its molecular weight suggest similar implications for the practical use of heparin in anticoagulant therapy.
Action of HL-A Specific Antibodies on Platelets in Vitro
Authors: Heinrich D. , Kessler C. , Stephinger U. , Kunkel W. , Mueller-Eckhardt C. 
Published: June 2019

Refractoriness to platelet transfusion in thrombocytopenic patients often is due to HL-A isoimmunisation. HL-A antibody-induced platelet alteration in vivo is associated with a reduction of platelet survival.Action of HL-A specific antibodies on platelets in vitro was studied applying serological (absorption/elution-experiments; micro-complement fixation), morphological (platelet spreading, electron microscopy) and functional parameters (clot retraction, platelet agglutination, 14C-serotonin uptake and 14C-serotonin release).Results: Incubation of platelets (PRP) with HL-A specific antisera induced a specific platelet agglutination with degranulation and 14C-serotonin release, furthermore a specific inhibition of 14C-serotonin uptake and clot retraction. Experiments with Prostaglandin E15 Apyrase, Heparin, ASA and EDTA in connection with a HL-A specific LDH-liberation from platelets suggest a lytic, complement-dependent action of HL-A antibodies on platelets in plasma (PRP).Experiments with washed platelets and HL-A specific eluates (D. Heinrich et al.: Vox Sang. 27, 310, 1974) indicate a second, nonlytic action of HL-A antibodies on platelets. Cofactors of the latter reaction are Ca++, fibrinogen and thrombin.
Inhibition of Virus-Induced Platelet Aggregation by Treatment of Platelets with Neuraminidase
Authors: Chernesky M. A. , Larke R. P. B. 
Published: June 2019

Washed suspensions of rabbit or human platelets aggregate and release their constituents (adenine nucleotides, serotonin and lactic dehydrogenase) when mixed with Newcastle disease virus (NDV) or Sendai virus (paramyxoviruses) in a stirred system at 37° C. Treatment of rabbit platelets with chromatographically purified neuraminidase which removed 10–20 ug of sialic acid/101 platelets reduced, by more than 95%, platelet aggregation and release of constituents by virus; treated platelets were as responsive to stimulation with ADP or thrombin as were control platelets. Virus, which normally becomes associated with aggregated platelets, failed to attach to neuraminidase-treated platelets and was recovered in platelet supernatant fluids. Subsequent aggregation of these mixtures of virus and neuraminidase-treated platelets with thrombin failed to trap NDV in platelet aggregates. Electron microscopy (carbon replica and thin-sections) revealed an absence of virus attachment on surfaces of platelets treated with neuraminidase.These data indicate that a receptor substance containing sialic acid present on the platelet surface is necessary to enable paramyxoviruses to attach and induce platelet aggregation and release of platelet constituents.
Distinction of Plasma Inhibitor of Activator-Induced Clot Lysis from Antiplasmins
Authors: Aoki N. , Matsuda M. , Moroi M. , Yoshida N. 
Published: June 2019

A fraction of human plasma prolongs the activator-induced clot lysis time and inhibits plasminogen activation by the plasminogen activators derived from various sources (urine and tissues). This fraction, designated as antiactivator fraction, was separatid from antiplasmin fractions (α2-macroglobulin and α1-antitrypsin) by gel filtration and affinity chromatography on Sepharose coupled with IgG of antiserum to α1-antitrypsin. Anti-activator fraction thus obtained exerted little antiplasmin activity but inhibited strongly activator-induced clot lysis.Inhibitory effect of plasma on urokinase-induced clot lysis (antiactivator activity) was assayed in various diseases and compared with antiplasmin activity. No correlation was found between the two activities, and it was concluded that the two activities are independent and are ascribed to two different entities.
A Physiological Study on the Releasing Mechanism of Plasminogen Activator from the Vascular Wall
Authors: Kitaguchi H. , Izaki S. 
Published: June 2019

Some precise information is described of the releasing mechanism of plasminogen activator from the vascular wall. Using the isolated hind leg of dog perfused with Hank’s solution under the physiologically controlled conditions by a modified Dale Schuster type circulation system, the activator activity and flow rate of the perfusate were carefully estimated every fifteen seconds after administering the vasoactive agents of different kinds.A transient but steep rise of the activator activity was definitely observed when some vasodilators (acetylcholine, histamine, bradykinin and eledoisin) and the strong vasoconstrictors (adrenaline, noradrenaline and vasopressin) were administered. However, such effect was hardly observed when other dilators (isoproterenol and papaverine) and a weak constrictor (serotonin) were given. Concerning the minimum effective dose and the total sum of the activator released effect of the active dilators was found clearly predominant compared with the active constrictors, In addition, it was indicated that, in term of releasing the activator, the constrictors required Ca ion but the dilators did not.Results obtained imply that the activator releasing is triggered by the strong vasoconstriction, and more predominantly by a Ca ion independent membrane reaction due to the vasodilators without accompanying the vasodilatation.
The Use of Logistic Analysis to Distinguish between Normal and Pre-Eclamptic Patients
Authors: Howie P. W. , Purdie D. , Begg C. , Forbes C. D. , Prentice C. R. M. 
Published: June 2019

Tests of coagulation and fibrinolysis were performed in 20 patients with severe preeclampsia and in 20 normal pregnant women. Compared with the normal patients, the women with severe pre-eclampsia had raised factor VIII, increased cryofibrinogen and reduced platelet counts. Despite increased resistance to urokinase-induced fibrinolysis, the pre-eclamptic women had lower plasminogen and increased serum and urinary F.D.P. levels. These results suggested that intravascular fibrin deposition was a feature of severe pre-eclampsia. In each test, the range of values in the pre-eclamptic women overlapped with the controls, so that no single test indicated whether intravascular coagulation was present in every case of severe pre-eclampsia. By the use of logistic analysis, it was possible to demonstrate that an abnormality of the coagulation and fibrinolytic systems was present in every case of severe pre-eclampsia. In 10 patients with moderate pre-eclampsia, the severity of the coagulation abnormality was intermediate between the severe cases and the controls.By sequential logistic analysis, it may be possible to anticipate the phase of clinical deterioration and permit delivery before the onset of fetal death. The haemostatic abnormalities would appear to be a constant and inevitable feature of pre-eclampsia.
Selective Release of Serotonin from Human Platelets by X-537 A, Acting as an Ionophore for Serotonin
Authors: Wörner P. , Brossmer R. 
Published: June 2019

The ionophore X-537 A facilitates the permeation of calcium through membranes. Human platelets exposed to X-537 A undergo a release of serotonin, which has been attributed to an increase in the concentration of cytoplasmic calcium, mediated by X-537 A. However, at a low concentration of X-537 A, platelets release serotonin but one cannot observe a release of heparin-neutralizing activity (PF4) and adenine nucleotides, an activation of clot-promoting activity (PF3), or a significant uptake of 45calcium into platelets. Electron micrographs of platelets after exposure to X-537A do not exhibit the alterations known to be coupled with the release reaction, despite a considerable release of serotonin. Two-phase partition studies demonstrate that X-537A is able to extract serotonin into an organic phase. In summary, these results indicate that X-537A causes a selective release of serotonin by transporting it through membranes. Only at high concentrations of X-537A can one establish an uptake of 45calcium by platelets and a release of PF4 and adenine nucleotides in addition to that of serotonin.(Supported by “Deutsche Forschungsgemeinschaft, Bonn”, Sonderforschungsbereich 90, “Cardiovasculares System”.)
Capillary Thrombosis as a Factor in the Evolution of Traumatic Brain Lacerations
Authors: Coccheri S. , Testa C. 
Published: June 2019

In a group of patients with Traumatic Brain Laceration (TBL) studies on blood coagulation and platelet function were performed in blood samples obtained during angiography from the omolateral carotid artery and jugular vein. Intraoperatory microbiopsies were also performed during neurosurgical operations in patients with TBL at different stages of evolution. In the acute stages of TBL necrosis of the endothelium and extensive micro-thrombosis with platelet material occurs in the capillaries around the damaged area. In the blood obtained from the jugular vein a fall in platelet count, platelet materials and positive paracoagulation tests can be observed.These data suggest that a process of regional intravascular coagulation occurs after TBL around the damaged area. Resulting microthrombosis may be regarded as a significant factor in the pathogenesis of acute ischemic intracellular edema in neurotraumatology.
Quick-Time Standardization
Authors: Canaveri Martínez A. A. , Alonso B. , Touceda M. , Pavlovsky M. , Bergna L. J. 
Published: June 2019

Ten different kinds of thromboplastin were studied from: A) Rabbit brain: 1) Britania, 2) Biochem, 3) Rivero, 4) Dade, 5) Simplastin and 6) Hyland; B) Pig lung: Geigy; and C) Human brain: 1) Academy of Medicine, Buenos Aires, and 2) Municipal Hematology Institute. They were compared with three International Standards: British Comparative Thromboplastins: BCT (Manchester), 69/223 and 70/178 (National Institute for Biological Standards and Control, London).The aim was to learn about the use of oral anticoagulants as there seems to be a lack of agreement in the results obtained at different centres due to the variety of thromboplastins used, also to the different meanings given to the words “therapeutical range”. Four or more different thromboplastins were studied the same day in 1 to 5 normals and 6 to 20 patients.The relative sensitivity of the different thromboplastins was establish. The sensitivity, the “ratio” and the percentage of activity varied markedly according to the kind of thromboplastin used. The difference was more marked with decreasing anticoagulation levels.