bluuebunny/crossref_metadata_2025 huggingface dataset:
AGILEγ-ray sources coincident with cosmic neutrino events
Authors: Lucarelli Fabrizio , Tavani Marco
Published: May 2019

Using data obtained by theγ-ray imager on board of the AGILE satellite, we systematically searched for transientγ-ray sources above 100 MeV in temporal and spatial coincidence with high-energy neutrino IceCube events. We found some significantγ-ray transients possibly associated with HESE neutrinos recently detected by the IceCube experiment. In this talk, we review the AGILE results and we will show that the probability of this association to be by chance is very low. One of the sources detected by AGILE is related to the blazar AGN TXS 0506+056. For the other sources, there are no obvious known counterparts.
Proton energy spectrum with the DAMPE experiment
Authors: De Benedittis Antonio
Published: May 2019

The DAMPE (DArk Matter Particle Explorer) experiment, in orbit since December 17th 2015, is a space mission whose main purpose is the detection of cosmic electrons and photons up to energies of 10 TeV, in order to identify possible evidence of Dark Matter in their spectra. Furthermore it aims to measure the spectra and the elemental composition of the galactic cosmic rays nuclei up to the energy of hundreds of TeV. The proton analysis and the flux with kinetic energy ranging from 50 GeV up to 100 TeV, at the end of two years of data taking, will be presented and discussed.
Gravitational waves: where we are, where we go
Authors: Ricci Fulvio
Published: May 2019

We review the present status of the Gravitational wave detectors on the Earth, focusing the attention on the present innovations and the longer term perspectives to improve their sensitivity. Then we conclude mentioning few potential searches of new Physics phenomena to be performed with these detectors and those of the third generation.
Karlsruhe Nuclide Chart – New 10th edition 2018
Authors: Sóti Zsolt , Magill Joseph , Dreher Raymond
Published: May 2019

Obtaining nuclear data is an international activity with new and updated data constantly being determined by thousands of scientists at major research centres worldwide. Because of the large amounts of data generated and the formats used to store these data, the field of nuclear data is highly specialised. To make the most important key data more accessible to a wider audience, nuclide charts have been developed. In this article, we present the scientific highlights of the new 10th Edition of the Karlsruhe Nuclide Chart. The main focus of this Chart is to provide structured, accurate information on the half-lives and decay modes, as well as energies of the emitted radiation for over 4000 experimentally observed ground states and isomer nuclides to an interdisciplinary audience.
Effects of waterborne luteinizing hormone and follicle-stimulating hormone on reproduction of the rotifer Brachionus calyciflorus (Monogononta: Brachionidae)
Authors: Alvarado-Flores Jesús , Rico-Martínez Roberto
Published: May 2019

This study used freshwater rotifers to evaluate the effects of two endocrine disrupting compounds (EDCs), luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which can be considered emergent contaminants in urban and rural wastewater and are of ecotoxicological importance. LH stimulates the synthesis of testosterone, whereas FSH promotes the maturation of follicles and sperm in vertebrates and invertebrates. However, in rotifers, there are no reports of the effects of chronic exposure to these hormones when added to reconstituted culture medium, as a way to study potential adverse effects that might occur in the environment. Therefore, we studied the reproductive effects of the rotifer Brachionus calyciflorus Pallas 1766 using a 4-day reproductive assay. Our results indicate that LH has a significant effect in increasing the production of females, males, and cysts, while FSH had no significant effect compared to control treatment. Additionally, our results indicate that LH exposure resulted in 0.33% of organisms being deformed, whereas FSH exposure resulted in 1.09% of organisms being deformed. Deformations included: (a) abnormal growth of lorica, (b) joined foot-head, (c) deformed anterior spine, and (d) deformed parthenogenetic eggs. The organisms with LH-induced deformations did not reproduce and only lived 48 h after 4 days of exposure, while those with FSH-induced deformities survived 15 days and produced 105 cysts with a hatching percentage of 58.10%. Our goal was to contribute to the knowledge of endocrine systems and endocrine hormones of rotifers, to explain the potential mechanism of endocrine disruption that results in adverse effects in freshwater rotifers.
Effect of initial tempers on mechanical properties of creep-aged AA2050
Authors: Li Yong , Yang Yo-Lun , Rong Qi , Shi Zhusheng , Lin Jianguo , Said Rajab
Published: May 2019

The evolution of mechanical properties of a third-generation Al–Cu–Li alloy, AA2050, with different initial tempers (as-quenched WQ, naturally aged T34 and peak-aged T84) during creep-ageing has been investigated in this study. A set of creep-ageing tests was carried out under 150 MPa at 155 °C with different durations for all initial temper conditions and tensile tests were performed subsequently to acquire the main mechanical properties of the creep-aged alloys, including the yield strength, ultimate tensile strength and uniform elongation. The evolution of these mechanical properties during creep-ageing has been discussed in association with precipitation behaviour of AA2050 alloys with different initial tempers. The results indicate that the T34 alloy is the best choice for creep age forming (CAF) applications among these initial tempers, as it provides better yield strength and uniform elongation concurrently after creep-ageing. In addition, a work hardening rate analysis has been carried out for all the creep-aged alloys, helping to understand the detailed dislocation/precipitate interaction mechanisms during plastic deformation in the creep-aged AA2050 alloys with WQ, T34 and T84 initial tempers.
Accumulation of intramuscular toxic lipids, a link between fat mass accumulation and sarcopenia
Authors: Capel Frederic , Pinel Alexandre , Walrand Stéphane
Published: May 2019

Aging is characterized by a loss in muscle mass and function, which is defined as sarcopenia. It weakens individuals by increasing the risk of falls and altering their quality of life. The loss of muscle mass results from the age-related impairment of the anabolic effect of nutrients and insulin, which normally increase and decrease muscle protein synthesis and degradation rates respectively. Alterations in muscle protein metabolism have been related to the accumulation of body fat and intramyocellular lipids. In particular, some lipid species such as ceramides or diacylglycerols have been described as inhibitors of the insulin signaling pathway in different models. Accumulation of these molecules in skeletal muscle could result from a lowered buffering capacity of circulating fatty acids by adipose tissue in response to the meal, a reduction of mitochondrial oxidative capacities or chronic inflammation. However, some nutritional strategies have been identified to limit or prevent the accumulation of lipotoxic metabolites and to improve the sensitivity of muscle to nutrients or insulin.
First detection of Cryptosporidium spp. in red-bellied tree squirrels (Callosciurus erythraeus) in China
Authors: Chai Yijun , Deng Lei , Liu Haifeng , Yao Jingxin , Zhong Zhijun , Xiang Leiqiong , Fu Hualin , Shen Liuhong , Zhou Ziyao , Deng Junliang , Hu Yanchun , Peng Guangneng
Published: May 2019

Cryptosporidium spp. are opportunistic pathogens that cause diarrhea in a variety of animal hosts. Although they have been reported in many animals, no information has been published on the occurrence of Cryptosporidium spp. in red-bellied tree squirrels (Callosciurus erythraeus). A total of 287 fecal specimens were collected from Sichuan province in China; the prevalence of Cryptosporidium spp., measured by nested-PCR amplification of the partial small-subunit (SSU) rRNA gene, was 1.4% (4/287). Three different Cryptosporidium species or genotypes were identified: Cryptosporidium parvum (n = 1), Cryptosporidium wrairi (n = 1), and Cryptosporidium rat genotype II (n = 2). The present study is the first report of Cryptosporidium infection in red-bellied tree squirrels in China. Although there is a relatively low occurrence of Cryptosporidium, the presence of C. parvum and C. wrairi, which were previously reported in humans, indicates that red-bellied tree squirrels may be a source of zoonotic cryptosporidiosis in China.
Wirksamkeit des Rezepts für Bewegung aus Patientensicht – die ärztliche Beratung und Handlungsabsichten/-konsequenzen nach erfolgter Rezeptverschreibung
Authors: Vogt Lutz , Hoppe Imke , Thoma Rebekka , Gabrys Lars , Friedrich Gundi , Coester Eckhard , Füzéki Eszter , Banzer Winfried
Published: May 2019

Einleitung Präventive Bewegungsberatungen durch niedergelassene Ärzte sind aktuell in Deutschland nicht großflächig implementiert. Das „Rezept für Bewegung“ will das ärztliche Bewegungsberatungsgespräch für inaktive Patienten verbindlicher gestalten. Ziel der Studie war es, die Wahrnehmung der Beratungsqualität aus Patientensicht und die daraus resultierenden Handlungsabsichten und -konsequenzen systematisch zu erfassen.

Methode Unter Verwendung eines standardisierten 17-Item-Instruments wurden 173 Patienten 3,9 ± 1,0 Monat(e) nach ärztlicher Beratung hinsichtlich Beratungszufriedenheit sowie Handlungsintention und -konsequenz anonym befragt. Die Dissemination erfolgte durch 12 kooperierende Arztpraxen in 8 Sportkreisen des Landessportbundes Hessen.

Ergebnisse Gemäß Fragebogenrücklauf konnten Angaben von 51 Patienten (56,1 ± 13,3 Jahre; 35w.) in die Auswertung eingeschlossen werden. Knapp 2/3 der Befragten waren in ihrer Lebensspanne vor Beratung sehr geringfügig körperlich aktiv (≤ 60 min/Woche). Die Beratung zum „Rezept für Bewegung“ wurde in 63 % der Fälle mit gut bis sehr gut bewertet. Nach eigenen Angaben besuchten mehr als die Hälfte der Befragten im Anschluss ein Bewegungsangebot im Verein, 53 % trieben mehr Sport, 51 % gestalteten ihren Alltag körperlich aktiver. Befragte, die die Ausführlichkeit der Beratung als gut bewerteten, trieben nach eigenen Angaben in der Folge der Beratung signifikant häufiger Sport als vor der Beratung OR 3,16 (95 % KI 1,07 – 9,33). Fast die Hälfte der Befragten wünschten sich zur Erleichterung des Einstieges in ein Bewegungsangebot mehr Unterstützung von ihrer Krankenkasse.

Diskussion Ärztliche Beratung im Sinne des „Rezepts für Bewegung“ kann als ergänzendes Instrument zur Sensibilisierung für das Thema Bewegung und Gesundheit unterstützen und zu entsprechender Steigerung der körperlichen Aktivität beitragen.
PSMA-ligand PET allows a more accurate therapeutic response evaluation of bone metastases in prostate cancer compared to computed tomography
Authors: Fech Viktor , Alberts Ian , Rominger Axel , Afshar-Oromieh Ali
Published: May 2019

A patient with bone metastases of prostate cancer was referred for 68Ga-PSMA-11 PET/CT. Compared to a 68Ga-PSMA-11 PET/CT four months previously, the CT-component of the current PET/CT showed morphological progress in all lesions despite continuous therapy with docetaxel and denosumab. Contrarily, the PET-component showed a reduction of tracer-uptake, which correlated with PSA decrease between the two PET/CT-scans (16.2 ng/ml vs. 3.1 ng/ml). This case highlights 68Ga-PSMA-11 PET/CT as a promising tool for therapy monitoring of prostate cancer and could serve as a basis for a novel monitoring strategy. Volume progress shown by CT must not be classified as tumor progress, but as bone remodeling following effective therapy.
Zinc Chelate Chromatography Of Fibrinogen
Authors: Scully M F , Kakkar V V
Published: May 2019

Fibrinogen when passed through columns of chelated zinc (bis-carboxymethyl amino - Sepharose 4B saturated with zinc) was bound firmly at pH 8.0 and in the presence of 0.8M NaCl. It was found possible to achieve a maximum concentration of bound fibrinogen of 7mg/ml of gel. No affinity was shown to columns without zinc. A linear pH gradient developed from pH 8.0 to 4.0 showed a sharp elution of fibrinogen at acidic pH values with an apparent pKa of 5.8 indicating the involvement of a histidine residue at the chelating site. Inclusion of lOmM dimethyl HC1 in the equilibrating buffer prevented absorption of the fibrinogen. Fibrinogen could also be removed by EDTA at pH 7.0. Plasma fibrinogen was observed to bind to such columns and eluted between pH 5.5 and 6.0.

Copper and nickel chelate columns were found to have an affinity for fibrinogen but not those prepared with calcium, magnesium or manganese. Concentrations of calcium chloride sufficient (0.1M) to fully saturate the calcium binding sites of fibrinogen did not affect attachment of the fibrinogen to the resin bound zinc nor concentrations of sodium chloride up to 1.5M. Inclusion of zinc chloride in the equilibrating buffer (up to 1.5mg/ml) did not affect the affinity.

When a plasmin digest containing fragmentes D and E was passed through zinc chelate columns fragment E was not bound and eluted in pure form (as shown by SDS electrophoresis) in the equilibrating buffer. Using a pH gradient pure fragment D was shown to be eluted with a pKa of 6.1. Fragment X and Y were also bound to zinc chelate columns.

These results show the possible presence of a reactive histidine or histidines on the D domain of fibrinogen capable of forming a dative bond with chelated forms of zinc.
It does not appear related to the calcium binding site and its properties are such as to indicate a functional importance. Rapid separation of fragments D and E may be achieved by such chromatography.
Effects Of Leucocyte Proteases On Structure And Activity Of Isolated Factor XIII Subunit A AND S
Authors: Holst F , Klingemann H G , Egbring R , Bohn H , Havemann K
Published: May 2019

In some diseases (septicemia, leucemia) an activation of clotting by thrombin (eg. DIC) or an unspecific proteolysis of clotting factors by leucocyte proteases can be responsible for coagulopathy.

We investigated in vitro the influence of elastase-like protease (ELP) and chymotrypsin-like protease (CLP) on isolated purified factor XIII subunit A and S using the SDS-PAA electrophoresis (Weber and Osborn, 1969). ELP and CLP was purified according to W. Schmidt (1974). Factor XIII was purified by Bohn and Haupt.

Results: Using increasing amounts of ELP a correlation between the ELP concentration and the factor XIII split products, which were generated, could be demonstrated. At high concentrations of ELP a complete disappearence of all factor XIII split products could be observed. These digestive effects were shown both on subunit A and on S. The proteolysis of factor XIII was also time dependent. The effects of CLP were not very different from those of ELP. When factor XIII subunit A was digested by ELP, a gradual loss of the ability to crosslink fibrin S occured. As in the literature aj-antitrypsin strongly and aprotinin slightly inhibited the ELP effects on factor XIII.

Despite the fact that antiprotease potential in vivo is very high, an accelerated turn over of clotting factors can be expected, when ELP forms complexes with its protein substrates like factor XIII. The decrease of factor XIII in some clinical conditions may be caused by leucocyte proteases.
Detection Of Potentially Embolic Intracardiac Thrombus In Patients With Cerebral Ischaemia
Authors: Donaldson R M , Humphrey C , Emanuel R W , Earl C
Published: May 2019

In a prospective study, 5 8 consecutive patients presenting clinically with transient or permanent focal cerebral ischaemia underwent cardiac assessment which included twodimensional echocardiography (2DE). All had been referred after neurological investigations failed to establish the underlying cause of the neurological event. 5 0 of these patients had no evidence of heart disease (Group 1); the other 28 patients had clinical evidence of an underlying cardiac abnormality or arrhythmia (Group 2). One of the patients in Group 1 had echocardiographic evidence of mitral valve prolapse; no cardiac pathology was visualised in the other 29 patients in this group. In 5 of the 28 patients from Group 2, intracardiac thrombus presumed responsible for the neurological manifestations was demonstrated by 2DE and histological confirmation obtained following surgery or at necropsy in 4 of these cases. No abnormality was found on 2DE in the other 23 patients. All acoustically dense thrombi were larger than 1.5 cm and had some degree of organisation. Two were recent, histologically showing red blood cells and mplatelet-fibrin columnation. The accoustical similarity of small thrombi to the surrounding blood or endocardium may hinder the sensitivity of the method.

The technique may help to define patients at risk from embolisation. As intracardiac thrombi are a common and potentially an easily prevented cause of stroke,a 2DE screen should be undertaken in patients with arrhythmias or clinical evidence of cardiac disease who have experienced one or
more episodes of cerebral ischaemia.
Platelet Thromboxane Increase During Cell. Separation In Healthy Blood Donors
Authors: Riess H , Hiller E , Schramm W , Howe J
Published: May 2019

An increasing number of healthy persons is subjected to extracorporal blood systems in order to obtain platelet and granulocyte concentrates. To assess the influence of extracorporal circulation on hemostasis we determined a spectrum of parameters in 20 blood donors before and after cell separation.

Obviously anticoagulation with ACD (acid citrate dextrose) is effective in preventing the activation of the plasmatic clotting system:
There were no significant changes in the levels of fibrinogen, plasminogen, soluble fibrin monomer complexes (SFMC, measured by quantitative gel filtration), antithrcmbin III (AT III, iinminological and functional)and fibrin degradation products (FDP, staphylococcal clipping test). On the other hand we observed a significant rise in the plasma levels of Thranboxane-B2 (TxB2, RIA) at the end of cell separation. This value exceeded the starting level more than twice. Serum levels of TxB2 were unchanged.

From an additional five blood donors blood samples were examined simultaneously from both the input and the output line of the cell separator 30 min after the beginning of extrcorporal circulation. No changes were seen in the fibrinogen-, SFMC-, AT III-, plasminogen- and FDP-levels. There was a persistent but not significant increase in the plasma levels of TxB2 in the output line of the cell separator whereas there was no such trend in the serum levels of TxB2.

F CB 3:R-AG and fibrinopeptide A of all 25 blood donors were measured and will be reported.

The increased levels of plasma TxB2 at the end of cell separation may express contact activation of platelets.
Effect Of The Stable Prostacy Clin-nilic, 7-OXO-PGI2 On Some Haemostatic Parameters
Authors: Blaskó Gy , Körmöczy P , Stadler I , Simonidesz V , Tömösközy I
Published: May 2019

7-oxo-PGI2 sodium salt produced by the Chinoin was investigated regarding some haemostatic and haemodynamic parameters. According to our results, 7-oxo-PGI2 is a powerful inhibitor of platelet aggregation induced by ADP and collagen (IC50: 10-15 ng/ml and 60-80 ng/ml respectively). It is stable in solution and the duration of its inhibitory effect on platelet aggregation in vitro is more than 3 hours (for PGI2 it is only 1,5 h ). Investigating the effect of this substance on the activities of the key-enzymes of blood coagulation (thrombin, Factor Xs and plasmin), we could neither demonstrate any effect on these enzyme activities nor on the inactivation of these enzymes by antithrombin-III and/or heparin at a concentration as high as 200 μg/ral.

The relative potency of 7-oxo-PGI2 on isolated bovine coronary artery is one tenth, as compared to PGI2. It decreases the systolic and diastolic blood pressure with a relative potency of 1:20 to PGI2 without effecting the heart rate. Comparing its stimulatory effect on platelet adenylate cyclase to that of PGI2, we have found, that 1 μM of 7-o xo-PGI2 activates this enzyme to 246%, while 1 μM of PGI2 causes a 370% activation. The platelet disaggregating activity of this compound -tested on cat Achilles tendon - is comparable to the effect of the natural compound.

The pharmacological profile of 7-oxo-PGI2 is similar to that of PGI , just even as another well known leading representativerGI -analogue - carboprostacyclin - , furthermore it is slightly preferred in certain conditions.
Platelet antibodies and circulating immune complexes in thrombocytopenic purpura
Authors: Wautier J , Kadeva H , Wautier M , Boizard B , Caen J
Published: May 2019

Forty five patients with thrombocytopenia (Platelet count below 105/ul) have been studied. Platelet associated IgG (Plat IgG) was determined by the method of Dixon et al (Normal range 38 ± 16 x 10-16g). Circulating immune complexes were detected by the [3H] Clq precipitation and the PEG precipitation techniques.

The sera were also tested for their thrombo-agglutinating activity (Aggl.). The results were:

The [3H] Clq test and the PEG test were significantly more frequently positive in patients with high level of Plat IgG.

The thromboagglutination seems to be independant of the level of Plat IgG. It could be correlated with the presence of circulating immune complexes in the serum.
Chemical Characterization of Duck And Goose Fibrinogen
Authors: Krajewski T , Nowak P , Cierniewski C
Published: May 2019

Chemical composition of duck /A. platyrynchos/ and goose /A. anser/ fibrinogens as well as their polypeptide subunit structure were analyzed. Amino acid composition studies of intact fibrinogens, isolated in the presence of proteolytic inhibitors, revealed their significant similarity. However, small differences between both fibrinogens in amounts of Tyr, Ser and Hys were detectable. Some differences between duck and goose fibrinogens in carbohydrate quantity were also found. They contained sialic acid /0.71 % and 0.78 %/, hexose /0.75 % and 1.1 %/ and N-acetylhexosamine /0.59 % and 0.75 %/. Electrophoretic analysis in 9 % polyacrylamide gels of reduced duck and goose fibrinogen showed the presence of two main bands /48 000 and 54 000 daltons/. The third, thrombin-sensitive band /59 000 daltons/ was weaker stained with Coomassie blue and amido black. Electrophoresis of thrombin digests of isolated fibrinogen and plasma fibrinogen demonstrated the identity of the heaviest peptide with the intact Aα chain. The remaining, probably partially degraded Aα chain, also sensitive to thrombin action, migrated together with the Bβ chain /54 000 daltons/. These observations were confirmed by isoelectric focusing analysis. Subunit polypeptide chains of duck and goose fibrinogen were isolated by CM-cellulose chromatography. Their chemical composition was also determined.
A Chromogenic Factor X Assay With New Standardized Reagents
Authors: Friberger P , Lenne C
Published: May 2019

A recently published method for Factor X (FX) assay (1) utilizing Russel's Viper Venom (RVV) and a chromogenic substrate has been further investigated by testing a large number of parameters. This method has been considered as a suitable method for monitoring coumarol treatment (Bergström et al).

The conditions for the activation of FX by purified preparations of the RVV have been studied as well as the conditions for FXa determination with a new chromogenic substrate Bz-Ile-Glu(γ-piperidyl)-Gly-Arg-pNA (S-2337). Both purified factors and normal plasma have been used. The effect of plasma inhibitors as well as the selectivity of the method has been studied.

The reproducibility and stability of the different reagents and standards have been studied and found to be good.

The amount of FXa activity obtained from normal human plasma has been titrated with FXa inhibitors of known purity.

1) Aurell L. et al, Thromb. Res., 11, 595 (1977)

2) Bergström et al, Thromb. Res., 12, 531 (1978)
Platelet Factor 3 Availability During Platelet Clumping - Studied with a Method Based on a Chromogenic Peptide Substrate
Authors: Korsan-Bengtsen K , Christenson B , Andersson I , Johnsen M
Published: May 2019

Platelet factor 3 (Pf3) together with factor V accelerates the conversion of prothrombin to thrombin by factor X a. Our method to determine platelet factor 3 activity is based on the measurement of thrombin formation with the substrate H-D-Phe-Pip-Arg-pNA in a system containing normal platelet poor plasma and Russells’ viper venom. There is a linear relationship between the rate of thrombin formation and the concentration of Pf3. The method is very sensitive. Thus 10 μl of frozen platelet rich plasma (PRP) or a lipid emulsion prepared from brain give absorbances > 2.0. When PRP is aggregated with ADP or collagen in concentrations which give maximal aggregation, no Pf3 activity whatsoever can be demonstrated. Treatment with kaolin or simply prolonged shaking of the PRP on the other hand increase the Pf3 activity extensively. Our conclusion is that aggregation of platelets per se do not make Pf3 available.
Prothrombin Metz : Purification and Characterization of a Variant of Human Prothrombin
Authors: Ribieto M , Elion J , Labie D , Josso F
Published: May 2019

For the purification of the abnormal prothrombin (Pt Metz), advantage has been taken of the existence in the family of three siblings who, being double heterozygotes for Pt Metz and a hypoprothrombinemia, have no normal Pt. Purification procedures included barium citrate adsorption and chromatography on DEAE Sephadex as for normal Pt. As opposed to some other variants (Pt Barcelona and Madrid), Pt Metz elutes as a single symetrical peak. By SDS polyacrylamide gel electrophoresis, this material is homogeneous and appears to have the same molecular weight as normal Pt. Comigration of normal and abnormal Pt in the absence of SDS, shows a double band suggesting an abnormal charge for the variant. Pt Metz exhibits an identity reaction with the control by double immunodiffusion. Upon activation by factor Xa, Pt Metz can generate amydolytic activity on Bz-Phe-Val-Arg-pNa (S2160), but only a very low clotting activity. Clear abnormalities are observed in the cleavage pattern of Pt Metz when monitored by SDS gel electrophoresis. The main feature are the accumulation of prethrombin l (Pl) and the appearance of abnormal intermediates migrating faster than Pl.
Bleeding Complications in Treatment with Asa and Anticoagulants
Authors: Dale J , Myhre E
Published: May 2019

Patients with prosthetic heart valves have a reduced platelet adhesiveness and a high incidence of arterial thromboembolic episodes. Therefore 148 patients with aortic ball valve prostheses were chosen for an antithrombotic study. They received either one gm. of ASA or placebo in combination with anticoagulants. In two years, 15 bleeding episodes developed in those taking ASA, seven during the first month. Two had intracranial hemorrhage, one died, while the others recovered completely. Six episodes occurred in the placebo group, three intracranial complications caused two deaths. The higher incidence of bleeding in the combined group was entirely due to gastrointestinal hemorrhage. In both groups, the occurrence and severity of bleeding correlated to the intensity of anticoagulant therapy. Low platelet adhesiveness also predisposed to bleeding.
The Effect of Antiplatelet Drugs on Plasma Betathromboglobulin in Coronary Artery Disease
Authors: Han P , Turpie A , Genton E , Gent M
Published: May 2019

Platelets play a role in the development and complications of coronary artery disease (CAD) and a number of abnormalities of platelet function which can be corrected by antiplatelet drugs have been described. Betathromboglobulin (BTG), a platelet-specific protein which is released from α-granules during platelet activation is significantly elevated in patients with angiographically demonstrated CAD (51.0 ± 31.0 ng/ml., n = 50) compared to normal (28.0 ± 8.0 ng/ml., n = 70) p < 0.001. The effect of sulphinpyrazone (800 mg.) or aspirin (1200 mg.)/dipyridamole (200 mg.) on plasma BTG in CAD was studied in a blind prospective crossover trial in 25 patients. Mean BTG concentration pre-treatment was 52.3 ng/ml. and after 1 month’s treatment with placebo, sulphinpyrazone or aspirin/dipyridamole mean plasma BTG concentrations were 53.5, 49.6 and 56.7 ng/ml. respectively. Analysis of variance showed no significant difference between the means (p > 0.1) . This study confirms increased plasma BTG concentrations in patients with CAD and indicates that therapeutic doses of these antiplatelet drugs do not significantly effect the BTG level and thus appear not to prevent α-granule release in CAD.
Prolonged Inhibition of PGI2 Production and Associated Increased Thrombogenic Effect in Arteries After Aspirin Administration
Authors: Buchanan M , Dejana E , Mustard J , Hirsh J
Published: May 2019

In recent studies in rabbits, high dose aspirin (ASA) which inhibited prostacyclin(PGI2) synthesis by veins augmented thrombus formation in jugular veins. This thrombogenic effect was short-lived and lasted only 1-2 hrs. We have shown that the inhibitory effect of ASA on PGI2 synthesis in arteries lasts much longer than in veins. We therefore examined the effects of high dose ASA on arterial thrombosis in rabbits by measuring PGI2 production, 51Cr platelet adhesion and 125I-fibrin accretion onto a mechanically-induced injury site in carotid arteries. PGI2 production, quantitated by a thrombin-induced 14C-5HT release assay, was 0.13 ± 0.01 ng/10 mm2vessel. 51Cr platelet adhesion and 125I-fibrin accretion onto these vessels 1 hr after injury was 1.00 ± 0.13 × 106 platelets and 57 ± 5 μg fibrin/10 mm2 respectively (mean = SE, n = 22). After ASA treatment (100 mg/kg, IV), PGI2 production was inhibited by at least 84% for 6 hrs and returned to 56% of control by 20 hrs. This PGI2 inhibition was associated with a marked increase in platelet adhesion (>100%) which lasted for at least 20 hrs. There was no significant increase in fibrin accretion. These results show that the more prolonged effect of ASA on PGI2 production in arteries than in veins is paralleled by a more prolonged thrombogenic effect on arterial vessel wall injury.
Quantitation of Platelet Adherence to Rabbit Aortae and Platelet Survival After Two Injuries With a Balloon Catheter
Authors: Kinlough-Rathbone R , Groves H , Maric S , Packham M , Mustard J
Published: May 2019

Following a single balloon catheter injury to a rabbit aorta (INJ 1) a monolayer of platelets covers the subendothelium within 10 min, the surface becomes relatively nonreactive to further platelet accumulation and platelet survival is not altered. We have now studied whether a second similar injury (INJ 2) of the non-reactive, smooth muscle cell-rich neointima 7 days after INJ 1 makes the surface of the neointima reactive to platelets or alters platelet survival. 51Cr-platelet adherence to the neointima of aortae subjected to INJ 2 in vitro 7 days after an initial in vivo injury was not significantly different from the adherence following a single in vitro injury (16,600 ± 3100 platelets/mm2 and 27,600 ± 4000 respectively, p > 0.2). In vivo adherence of 51Cr-platelets to the surface of rabbit aortae was similar following INJ 1 (0.084 ± 0.009% of the circulating platelets) and INJ 2 (0.130 ± 0.03%, p > 0.2). Platelet survival after injury to the neointima was not significantly different in animals with an undamaged aortic endothelium (74.6 ±5.9 hr and 80.2 ± 4.3 hr respectively, p > 0.5). Thus, a second injury involving the smooth muscle cell-rich neointima that forms after removal of the endothelium with a balloon catheter does not cause more platelets to accumulate than the initial injury, nor shorten platelet survival.
Conformation of the γ-Carboxyglutamic Acid-Rich Region of Prothrombin: Conformation-Specific Antibodies as Structural Probes
Authors: Furie B , Blanchard R , Tai M , Provost K , Furie B
Published: May 2019

Stabilization of the tertiary structure of bovine prothrombin (PT) by Ca(II) has been evaluated immunochemically using conformation-specific antibodies directed against limited regions of the protein. Antisera raised against native PT or des-γ-carboxy PT (AbPT) were fractionated by sequential immunabsorption using affinity chromatography. Three antibody subpopulations, specific for different determinants on the protein, were isolated and evaluated using RIA: (1) Anti-(12-44), directed against the Gla-rich region 12-44, requires Ca(II) or other metals to interact strongly with PT. Anti-(12-44) cross-reacts poorly with AbPT, factor IX, factor X, and human PT; (2) Anti-PT-Ca(II) is specific for the binary PT-Ca(II) complex and does not interact with PT. Anti-PT-Ca(II) is directed against multiple antigenic determinants in the fragment 1 region; (3) Anti-AbPT is specific for AbPT and does not cross-react with PT. We conclude that occupancy of the high affinity metal binding site by metal ions is associated with a significant change in the conformation of the 12-44 region and other aspects of the N-terminal portion of PT. These antigenic surfaces are not present in AbPT. Conversely, some determinants on AbPT are not observed on PT. These results are consistent with our current model of the role of Gla in metal-dependent intramolecular and intermolecular bridging in the vitamin-K-dependent proteins.
Evidence That Thrombin Releases Fibrinopeptide B From Non-Polymerizing Fibrin
Authors: Brosstad F , Kierulf P , Gravem K , Godal H
Published: May 2019

When thrombin acts upon fibrinogen (Fg),substantial amounts of fibrinopeptide A(FPA) are released prior to significant release of fibrinopeptide B(FPB) .It has been claimed that polymerization of des-AA fibrin is a prerequisite for the release of FPB from des-AA fibrin,by exposing structures(conformational changes) required for the FPB part of the B beta chain to be recognized by thrombin(Blamback,Hogg and Blonback,1976,1978). To test this theory, either Fg or des-AA fibrin (made by exposure of Fg to insol. reptilase in urea) were exposed to thrcmbin(1 or 100 NIH units) in a non-polymerizing system(2.5 M urea, pH 7.4, I=0.15, temp.+20°C),measuring FPA release(FPA-RIA +N-terminal analysis) and FPB release (N-terminal analysis). At 1 NIH unit of thrombin,complete release of FPA from Fg in urea occurred,whilst no FPB release frcm Fg or des-AA in urea were noted,irrespective of the incubation time. (Potency of thrcmbin during incubation time was unchanged) .Incubation with 100 NIH units of thrcmbin caused complete release of both FPA and FPB frcm 30 mg of Fg or des-AA fibrin in urea within 5 min,and chromatography of the resulting des-AABB fibrin, (80 × 2 cm,Sepharose 4B,2.5 M urea demonstrated a homogenous elution profile, indicating absent polymerization.lt seems likely that urea in seme way interferes with the affinity of thrcmbin for FPB,which might be compensated for by the use of high thrombin concentrations. It is concluded that polymerization is not a prerequisite for the release of FPB by thrcmbin.
Immune Response to Human Fibrinopeptide B
Authors: Wilner Georqe , Thomas David , Nossel Hymie
Published: May 2019

The serologic and cellular immune response to human fibrinopeptide B (hFPB), a unique thrombin proteolytic product of the fibrinogen Bβ chain (Bβl-14), was studied as a basis for developing immunologic probes to quantitate restricted sequential regions in the fibrinogen molecule. Outbred rabbits hyperimmunized with hFPB-bovine albumin conjugates produced anti-hFPB antibodies, as measured by radioimmunoassay (RIA) using 125I-hFPB analogue as tracer. Immunoreactive sites seen by these sera were characterized in terms of displacement of bound radiolabeled tracer by synthetic homologues of the hFPB sequence. In 4 immune rabbit sera, displacement of binding comparable on a molar basis to using hFPB as inhibitor was obtained with fragments Bβ3-14, 5-14 and 7-14, but not with fragment Bβ9-14. In an additional 3 sera, inhibition comparable to intact. hFPB occured only with fragments Bβ3-14 and 5-14. In 3 of the 7 sera tested, Argl4 seemed to contribute critically to hFPB antigenicity. To study the cellular immune responsiveness to hFPB, inbred strain 2 guinea pigs were immunized with unconjugated hFPB. No antibody was demonstrated by RIA up to 1 month following immunization. However, immune guinea pig T-cells showed a dramatic hFPB-specific proliferative response, as determined by 3H-thymidine incorporation. These cells were also stimulated by fragments Bβ3-14, 5-14 and 7-14, but not by fragments Bβ9-14 and 1-13. It is concluded that dominant antigenic determinants for both species reside in the COOH-terminal region of hFPB. (Supported by grant AI-14226 from NIAID, USPHS, and grants HL-15486 and HL-22642 from NHLI, NIH.)
Inhibition of the Activities of α2-Plasmin inhibitor (PI) and CI inhibitor (CI-Inh) by the Synthetic Fibrinolytic Agent, 3-Hydroxypropyl Flufenamide (Flu-HPA)
Authors: Miles L , Burnier J , Verlander M , Goodman M , Kleiss A , Griffin J
Published: May 2019

Flu-HPA is one of a series of flufenamic acid derivations that enhances plasminogen-dependent clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The influence of Flu-HPA on the inhibition of purified plasmin by purified PI was studied. PI activity was assessed by its inhibition of the clevage of the tripeptide S-2251 (H-D-Val-Leu-Lys-pNA) by plasmin. Flu-HPA was dissolved in DMF or in methonol and preincubated with PI before addition of plasmin. At Flu-HPA concentrations greater than 1mM and up to 60mM, the inhibitory activity of PI was totally lost. The inhibitory effect of normal human plasma on plasmin was also completely abolished at concentrations of Flu-HPA between 2.5 and 40mM. The effect of Flu-HPA on the inhibition of purified plasma kallikrein by purified CI-Inh was also studied. CI-Inh activity was measured by its inhibition of cleavage of the tripeptide Bz-Pro-Phe-Arg-pNA by kallikrein. When Flu-HPA, dissolved in DMF or in methonol, was preincubated with CI-Inh, a concentration dependent inhibition of CI-Inh activity was observed. CI-Inh activity was abolished by concentrations of Flu-HPA greater than 1mM. Flu-HPA also inhibited the activity of CI-Inh on purified Factor XIIa. These observations suggest that this flufenamic acid derivative may enhance fibrinolysis not only by inhibiting PI activity but also by decreasing the inactivation of plasminogen activators by CI-Inh.
Abnormal Blood Rheology in Young Male Diabetics With and Without Retinopathy
Authors: Lowe G , Drummond M , Belch J , Lowe J , MacCuish A , Manderson W
Published: May 2019

We compared red cell deformability (filtration rate through 5 µ sieves), blood viscosity (rotational viscometer), haematocrit, plasma fibrinogen and plasma viscosity in young male diabetics (age ˂50 years) and normal controls matched for age and smoking habit. Diabetics with no retinopathy or other vascular complications (n = 20) had normal red cell deformability, but increased blood viscosity at shear rates of 100s-1(p ˂0. 05) and 1s-1(p ˂0. 01), due in part to moderate elevations of haematocrit, fibrinogen and plasma viscosity. Diabetics with retinopathy (n = 10) had a more marked increase in viscosity and also reduced red cell deformability (p ˂0. 05). Increased blood viscosity is present prior to the onset of detectable vascular complications in male diabetics, while reduced red cell deformability is associated with complications.
A New Fluorogenic Substrate Method for Assay of Bacterial Endotoxins Using Limulus Hemocyte Lysate
Authors: Harada T , Ohki M , Niwa M , Iwanaga S
Published: May 2019

Limulus hemocyte lysate contains a proclotting enzyme, which is transformed to the active clotting enzyme in the presence of gram-negative bacterial endotoxins. The clotting enzyme coagulates a clottable protein, named coagulogen, contained also in the lysate. This gelation reaction of the lysate, named Limulus test, has been widely employed as a simple and very sensitive assay method for endotoxins. We developed a new fluorogenic substrate, Boc-Leu-Gly-Arg-4-methylcoumarin amide, for Limulus clotting enzyme and established an enzymatic assay method for endotoxins, using the substrate. Because the endotoxin mediates the activation of proclotting enzyme in the lysate, the measurement of amidase activity could be applicable for quantitation of the endotoxins. In fact, the amidase activity determined fluorometrically increased by increasing concentration of E. coli 0111: B4 endotoxin added to the lysate, and a linear relationship between the toxin concentration and the activity was observed in the range of 5X10-6to 5xl0-2 µg endotoxin. The method was a fifty times more sensitive than that of the Limulus test and was very reproducible. However, the method was not directly applicable for the assay of endotoxins in circulating blood, as the amidase activity was strongly inhibited by antithrombin III and α2-plasmin inhibitor. Thus, some pretreatment with heat or chloroform on plasma samples before the assay was required.
Pulmonary Insufficiency in the Rat After Intravascular Coagulation and Inhibition of Fibrinolysis - Studies on Pulmonary Microcirculation and Pathophysiology
Authors: Gerdin B. , Saldeen T. , Sandler H. , Sedin G.
Published: May 2019

In posttraumatic pulmonary insufficiency microembolism of fibrin to the lungs and inhibited fibrinolysis have been given key-roles and the term "the delayed microembolism syndrome" has been designated to those cases. The pathogenetic mechanisms involved are only to a limited extent known. Those were investigated in a rat model. Fibrinolysis was inhibited with AMCA and intravascular coagulation induced by a 5-min injection of thrombin, 500 NIH/kg b.w.. Within 5 min a profound consumption of fibrinogen occurred and 125-la- belled fibrin was embolized to the lungs. At that time the alveolar circulation was decreased, vasoconstriction and platelet-red cell aggragates appeared as seen by in vivo microscopy and arterial P02 was diminished irrespective of fibrinolysis. After restitution for 1 h a progressive pulmonary insufficiency with P02 decrease and PC02 retention occurred. Trasylol® did not influence on pulmonary damage. Converting enzyme activity was not diminished. A retention of fibrin degradation products (fdp) occurred in the lungs and infusion of low molecular weight fdp aggravated pulmonary oedema. Lung mast cells were partly degranulated and mepyramine maleate slightly counteracted pulmonary oedema. It is concluded that release of vasoactive low molecular weight fdp probably plays a causal role in oedema formation; probably in part by releasing histamine from lung mast cells.
Comparisons of Biochemical and Pharmacological Properties of Prostacyclins with Modified ω-Side Chain
Authors: Weithmann K. U. , Bartmann W. , Beck G. , Lerch U. , Konz E. , Schölkens B. A.
Published: May 2019

PGI2-analogs in which the n-pentyl moiety in position 15 was replaced by several residues, were subjected to structure-activity studies. Some of the modified PGI2’s showed remarkable potency in regard to antiplatelet and vasodilator actions. in order to evaluate these potencies the inhibition of arachidonic acid induced platelet aggregation in human platelet rich plasma, relaxation of bovine coronary artery (BCA) and systemic blood pressure (BP) in the anesthetized rat were determined. Platelet aggregation was inhibited by PGI2 with an IC50 approx. 3-10-9M, BP was decreased in a dose dependent manner with an ED25, of 0.23 ug/kg i.v. and a marked relaxation of BCA was observed. Similar results were obtained with PGI2-methylester. Substitution of the n-pentyl moiety by cyclohexyl, 3-furyl-2-ethyl or 3-thienyl-oxymethyl resulted in PGI2- and PGI2-methyl-ester-analogs with high biological activity, whereas substitution by T6,16-dimethyl-18-oxa-alkyl or phenoxymethyl caused a loss of activity in the models used. The potency of the prostacyclins in the platelet model seem to depend upon their ability to elevate the platelet cyclo-AMP level. Thus the antiplatelet potency of modified PGI2’s may reflect their ability to affect the adenylate cyclase system.
The Presence of Antithrombin Activity in Platelets
Authors: Czapek E. E. , Kwaan H. C.
Published: May 2019

The platelet has been implicated as the nidus around which clot formation occurs. We therefore decided to investigate whether any antithrombotic activity was associated with platelets. Thrombin activity was measured using the chromogenic substrate S-2238. Freshly prepared human platelet rich plasma (PRP) and platelet poor plasma (PPP) were found to have similar amounts of antithrombin activity. This antithrombin activity could be easily removed from a platelet pellet by repeated washing. However, sonicating PRP resulted in the appearance of additional antithrombin activity. After 6 minutes of sonication, the antithrombin activity of PRP decreased to 35% of presonication levels, whereas the antithrombin activity of PPP remained 100%. When subjected to Laurell Immunoelectrophoresis using an antibody to antithrombin III (AT-III), a greater amount of antigen was detected in PRP than in PPP. We conclude that platelets contain antithrombin material which is probably AT-III.
Abnormal Ristocetin-Aggregation of Platelets in Uraemia and on Haemodialysis Therapy
Authors: Woods H. F. , Turney J. , Weston M. J.
Published: May 2019

Impaired platelet aggregation to ADP and collagen is recognised in uraemia and the loss of normal platelet function contributes to the prolonged capillary bleeding time observed in uraemia. in von Willebrand’s disease prolongation of capillary bleeding time is associated with impaired platelet aggregation to ristocetin because of a relative or absolute deficiency of the Factor VIII-Ristocetin Cofactor. We have studied platelet aggregation to ristocetin and Factor VIII coagulant activity (CA) and related antigen (RA) in 14 uraemic and 28 dialysed patients. Ristocetin aggregation (delta-0.D/min) was significantly less in uraemia (50 ± 21: m ± S.D) and in dialysis patients (38 ± 18) than in controls (78 ± 20). Factor VIII CA and RA were significantly higher in uraemic and dialysed patients than in controls.

In crossover studies plasma from uraemic patients either enhanced or did not change ristocetin aggregation of normal platelets but plasma from dialysed patients impaired ristocetin aggregation of normal platelets. Plasma from dialysed patients was not contaminated by heparin. Thus in uraemia impaired platelet aggregation to ristocetin is unlikely to be due to a Factor VIII deficiency and may be due to a membrane defect as in Bernard-Soulier disease. in dialysed patients’ plasma there appears to be an additional circulating inhibitor of platelet-ristocetin interaction.
Antithrombin III, Heparin Cofactor and Antifactor Xa in Relation to Age, Sex and Pathological Conditions
Authors: Panicucci F. , Sacrioanti A. , Pinori E. , Vispi M. , Conte B. , Lecchini L.
Published: May 2019

Determinations of AT-III activity, heparin cofactor activity, antifactor Xa activity and AT-III protein were carried out in 200 healthy adults, evenly distributed within age and sex groups, in 60 patients with cerebral thrombosis and in 20 oral contraceptive users. There was a positive correlation between AT-III protein and its activities in normal subjects and in patients with cerebral thrombosis. in oral contraceptive users the positive correlation was between AT-III protein and its activities, antifactor Xa activity excepted. The mean AT-III protein and heparin cofactor activity values decreased in males with age and were significantly lower in the groups between 50 and 70 years. The mean AT-III protein and heparin cofactor activity values decreased slightly in women in fertile age and were lower in the 40 to 50 age-group. The mean AT-III protein and its activities values did not show any variation in the patients with cerebral thrombosis. The mean antifactor Xa activity value in the women, taking the pill for 3 months, decreased, whereas the other AT-III activities and AT-III protein were unchanged.