bluuebunny/crossref_metadata_2025_split huggingface dataset:
Haematocrit: Relationships with Blood Lipids, Blood Pressure and other Cardiovascular Risk Factors
Authors: Wannamethee Goya , Gerald Shaper A 
Published: July 2018

SummaryThe relationship between haematocrit and cardiovascular risk factors, particularly blood pressure and blood lipids, has been examined in detail in a large prospective study of 7735 middle-aged men drawn from general practices in 24 British towns. The analyses are restricted to the 5494 men free of any evidence of ischaemic heart disease at screening.Smoking, body mass index, physical activity, alcohol intake and lung function (FEV1) were factors strongly associated with haematocrit levels independent of each other. Age showed a significant but small independent association with haematocrit. Non-manual workers had slightly higher haematocrit levels than manual workers; this difference increased considerably and became significant after adjustment for the other risk factors. Diabetics showed significantly lower levels of haematocrit than non-diabetics. In the univariate analysis, haematocrit was significantly associated with total serum protein (r = 0*18), cholesterol (r = 0.16), triglyceride (r = 0.15), diastolic blood pressure (r = 0.17) and heart rate (r = 0.14); all at p <0.0001. A weaker but significant association was seen with systolic blood pressure (r = 0.09, p <0.001). These relationships remained significant even after adjustment for age, smoking, body mass index, physical activity, alcohol intake, lung function, presence of diabetes, social class and for each of the other biological variables; the relationship with systolic blood pressure was considerably weakened. No association was seen with blood glucose and HDL-cholesterol. This study has shown significant associations between several lifestyle characteristics and the haematocrit and supports the findings of a significant relationship between the haematocrit and blood lipids and blood pressure. It emphasises the role of the haematocrit in assessing the risk of ischaemic heart disease and stroke in individuals, and the need to take haematocrit levels into account in determining the importance of other cardiovascular risk factors.
Factor VII Activity and Antigen in Haemophilia B Variants
Authors: Mazzucconi M G , Bertina R M , Romoli D , Orlando M , Avvisati G , Mariani G 
Published: July 2018

SummaryTwenty three patients belonging to 18 different pedigrees of Haemophilia B were studied with regard to ox-brain prothrombin time and its correlation to factor VII.Eleven among them were B-negative (no detectable factor IX antigen), five were B-reduced (factor IX antigen detectable but below the normal values) and seven were B-positive (normal levels of factor IX antigen).Ox-brain prothrombin time was found prolonged (≥ x̄ + 2.5 SD:99% confidence limits) in nine patients. Factor VII Activity (VII: C) was found reduced in 1/11 B-negative, in 2/5 B-reduced and in 4/7 B-positive patients. Factor VII Antigen (VII: Ag) was found normal in all but one patient.The ratio VII:C/VII:Ag was abnormal in eight patients independently from the variant of Haemophilia B. The underlying defect which causes the prolongation of Ox-brain prothrombin time due to factor VII: C mild deficiency is heterogeneous. Age, a mild Vitamin K deficiency, the presence of an inhibitor of Factor VII activation and other unknown causes, may be responsible for this pattern.
The Interrelationship between Thromboxane Biosynthesis, Aggregation and 5-Hydroxytryptamine Secretion in Human Platelets in Vitro
Authors: Best L C , Holland T K , Jones P B B , Russell R G G 
Published: July 2018

SummaryPlatelet aggregation, secretion of 5-hydroxy tryptamine and production of thromboxane B2 were monitored simultaneously in human platelet suspensions in the absence and presence of cyclooxygenase or thromboxane synthetase inhibitors. Aggregation, secretion and thromboxane B2 formation in response to either sodium arachidonate or epinephrine were blocked by aspirin or by 1-N-butyl imidazole suggesting that thromboxane biosynthesis was an essential requirement for platelet activation by these agents. In contrast, thrombin and collagen could apparently induce aggregation and secretion via two pathways: at low doses involving thromboxane production, but at higher doses by a direct mechanism independent of thromboxane biosynthesis. In the case of ADP, inhibition of thromboxane production blocked secretion but had little effect on aggregation, indicating that secretion was probably dependent on thromboxane biosynthesis which probably occurred as a result of aggregation. Thus it appears that although the processes of thromboxane production, release of dense granule constituents and aggregation may often be intimately linked, each process can occur independently of the other, depending upon the stimulus used.
Heparin Induced Thrombocytopenia: a Prospective Study
Authors: Ansell Jack , Slepchuk Nicholas , Kumar Raminder , Lopez Aaron , Southard Luzbella , Deykin Daniel 
Published: July 2018

SummaryThrombocytopenia occurred in 11.6% of 43 patients prospectively randomized to receive either bovine lung or porcine mucosal heparin. Four patients received bovine heparin and developed mild to moderate thrombocytopenia after eight to twelve days which resolved when therapy was stopped in one to six days. One patient received porcine heparin and developed mild thrombocytopenia after four days. The thrombocytopenia resolved in one day in spite of continued heparin therapy.Serial blood samples from the five thrombocytopenic patients were studied for their in vitro effect upon normal platelets. These samples induced a high release of serotonin from normal platelets or caused normal platelets to aggregate in the presence of additional heparin. Release or aggregation coincided with or occurred shortly after nadir platelet counts were reached and returned toward normal following cessation of heparin.Our data constitute the first prospective study of heparin induced thrombocytopenia in which serial blood samples were studied before, during and following the onset of thrombocytopenia. They strongly support the presence of a heparin dependent co-factor, presumably an antibody, as the cause for thrombocytopenia.
Untersuchungen zur Funktion des Antithrombins III
Authors: Schimpf Kl , Lenhard J 
Published: July 2018

ZusammenfassungBei Steigerung der Gesamtaktivität des Gerinnungssystems steigt die Aktivität des Antithrombins III.Bei Abnahme der Gesamtaktivität des Gerinnungssystems sinkt die Aktivität des Antithrombins III.In venösem Blut ist das Antithrombin III aktiver als in arteriellem Blut.Die Ergebnisse werden erhalten mit Plasma, mit Serum und nach BaSO4-Behandlung beider.
Beitrag zum Problem der Thrombozythämie Thromboplastinbildung in Gegenwart höherer Thrombozytenkonzentrationen
Authors: Hiepler E 
Published: July 2018

Zusammenfassung1. Auf Grund von In-vitro-Versuchen über die Beeinflussung der Thromboplastinbildung durch Anreicherung normaler Thrombozyten wird eine Hemmung der Thromboplastinbildung durch einen bloßen Thrombozytenüberschuß für unwahrscheinlich gehalten.2. Nur geschädigte Thrombozyten hemmen bei genügender Anreicherung die Thromboplastinbildung.3. Soweit sich unsere In-vitro-Untersuchungen auf die Zustände bei Thrombo-zythämie übertragen lassen, wird die Vermutung ausgesprochen, daß eine Blutungsneigung bei Thrombozythämie nur in solchen Fällen auftreten kann, bei denen die Thrombozythämie mit einer gleichzeitigen, wenigstens partiellen Schädigung der Thrombozyten einhergeht.
Canine Hemophilia
Authors: Wurzel Harold A. , Lawrence William C. 
Published: July 2018

SummaryHemophilia A is reported in a Shetland sheepdog. The history, clotting defects and clinical course were similar to that seen in human hemophilia. As far as we know, no evidence of hemophilia has been reported in this breed. Bleeding episodes could be controlled by fresh frozen plasma given either intravenously or intraperitoneally.Due to the disability of the dog and his inability to reproduce, he was destroyed. However, 2 female litter mates remain. We plan to try to establish a colony of these animals for further study.
The Influence of Contact and Prothrombin on Intermediate Product I Formation
Authors: Shanberge J. N , Duckert F 
Published: July 2018

SummaryIn the in vitro generation of intermediate product I, in which non-purified components are used, both prothrombin and foreign surface “contact” are essential for the formation of optimum activity.
Most of the time interval required before optimum intermediate product I activity is reached is the time needed for potentiation of intermediate product I as well as for the conversion of prothrombin to thrombin.
In the system studied, it is felt that, in the absence of prothrombin, intermediate product I activity is blocked by the presence of an inhibitor. The action of thrombin would then be to overcome the inhibitor.
The apparent increase in factor IX activity, observed during the generation of intermediate product I as measured by the one-stage method, is due to the non-specific clot-promoting effect of intermediate product I on the assay.
Antithrombin II Anticoagulant (Autoprothrombin II-A)
Authors: Seegers Walter H. , Ulutin Orhan N. 
Published: July 2018

SummaryAutoprothrombin II-A activity frequently develops when the autoprothrombin II fraction of prothrombin is dried from the frozen state. When the anticoagulant activity develops, the N-terminal amino acid arginine is found, but not when the anticoagulant activity does not develop. The anticoagulant autoprothrombin II-A retarded the conversion of prothrombin to thrombin when three different procoagulants were used; namely, platelet cofactor I, autoprothrombin II, and lung extract. The procoagulant power of the platelet cofactor I is most easily depressed. It is postulated that autoprothrombin II-A activity develops when prothrombin activates and that platelet cofactor I is a receptor of the anticoagulant. In that way the other procoagulants are not ordinarily inhibited by the autoprothrombin II-A. As a further extension of this speculation, attention is brought to the idea that autoprothrombin II-A could be present in certain hemorrhagic diseases. In the PTA patient there is no autoprothrombin II and most likely no autoprothrombin II-A. The close chemical relationship of these two prothrombin derivatives thus may account for the multiple deficiency.
The Influence of Some Anticoagulants and Fibrinolytic Substances on Mice Fibroblasts (Strain L) in Tissue Culture
Authors: Peters K , Matis P 
Published: July 2018

SummaryThe action of some anticoagulants and fibrinolytic substances on the culture of mice fibroblasts is described. Actase and streptokinase show a relatively high toxicity. Beta-heparins are more toxic than alpha-heparins. For pentosans the cytotoxic action is inversely proportional to the molecular weight. Marcoumar is more toxic than coumarin without anticoagulant activity. Variations of the concentration of factors VII, IX and X are of no importance for the cells. Cells 4 hours after explantation are not basically more sensitive than cells 24 hours after explantation.
Eine quantitative Einstufenmethode zur Bestimmung des Thrombozytenfaktors 3
Authors: Egli H 
Published: July 2018

ZusammenfassungEs wird eine einfache Methode beschrieben, die quantitative Bestimmungen der Aktivität des Thrombozytenfaktors 3 ermöglicht. Dem Einstufenprinzip Quicks folgend wird bei Konstanz aller übrigen Gerinnungsfaktoren der Einfluß der allein variabel gehaltenen Faktor-3-Aktivität einer Thrombozytensuspension (oder der Einfluß äquivalent wirkender Substanzen) auf die Gerinnungszeit einer Testmischung bestimmt. Die Konstanz und zugleich optimale Konzentrierung aller übrigen Gerinnungsfaktoren wird durch ein Gemisch aus thrombozytenfreiem Zitratplasma und kontaktaktiviertem Serum erreicht. Der Zusatz von Serum sichert den konstanten Einfluß jener. Gerinnungsfaktoren, die ausschließlich im Serum enthalten sind und erst nach erfolgtem Kontakt mit benetzbaren Oberflächen maximale Aktivität aufweisen. Es wird gezeigt, daß die Wirkung dieses (oder dieser) serumständigen Gerinnungsfaktoren sich in verkürzten Gerinnungszeiten manifestiert.Durch Einfrierversuche mit Thrombozyten wird der bereits bekannte, aber noch umstrittene Befund bestätigt, nachdem eine volle Aktivität des Thrombozytenfaktors 3 erst nach erfolgter Thrombozytolyse nachweisbar ist.Die angegebene Methodik erscheint besonders für vergleichende Untersuchungen der Plättchenfaktor-3-Aktivität in Thrombozytensuspensionen oder in Suspensionen äquivalent wirkenden Substanzen, wie dem aus Hirn aufbereiteten lipoidhaltigem Chloroformextrakt, geeignet. Desgleichen ermöglicht sie eine quantitative Aktivitätskontrolle derjenigen Elämostyptika, deren Wirkungsprinzip dem des Thrombozytenfaktors 3 entspricht, was am Beispiel des Tachostyptans demonstriert wird.
On the Effect of Heparin at Various Concentrations with Particular Reference to Increased Heparin Resistance Measured by the Plasma Heparin Thrombin Time
Authors: Holger-Madsen T 
Published: July 2018

SummaryThe heparin thrombin time was investigated in platelet-poor citrated plasma by determining the clotting time with thrombin after addition of heparin. At increasing heparin concentrations the heparin thrombin time was prolonged, reaching a maximum at a certain concentration. At higher concentrations the effect of heparin decreased, the heparin thrombin time getting shorter. At the highest concentrations there was again a full heparin effect, the heparin thrombin time being again prolonged to a maximum. In a study of plasma from patients with increased heparin resistance, in the form of a shortening of the heparin thrombin time in relation to normal, this was found to apply within all the studied ranges of heparin concentration.
A Two-Stage Assay Method for Hageman Factor Activity
Authors: Iatridis Sotirios G. , Ferguson John H. 
Published: July 2018

SummaryA two-stage assay method for assaying Hageman factor (HF) activity has been described. The method is based on the ability of a diluted test plasma or surface factor preparation to correct the clotting defect of a HF-deficient substrate plasma in a modified thromboplastin screening test. This method, being designed for investigating relative increase or decrease of HF activity, could also be used in a system with optimal amount of kaolin for assaying maximal HF activity.
A Naturally Occurring Inhibitor of Christmas Factor (Factor IX)
Authors: Hardisty R. M 
Published: July 2018

SummaryThe presence of a circulating anticoagulant in the plasma of a 37-year old man with Christmas-disease resulted in failure of response to transfusion, but did not otherwise affect the clinical severity of his disease.The circulating anticoagulant inhibited blood thromboplastin formation, but was inactive in the presence of brain extract or preformed blood thromboplastin. Its physicochemical properties are described.Evidence is presented that the anticoagulant is a specific irreversible inhibitor of factor IX. Its effect on thrombin generation is compared quantitatively with its inhibitory action against factor IX.Immunological tests provided no evidence that the inhibitor was an antibody. The patient was found to respond less actively to immunisation with tetanus toxoid than his brother, whose blood contained no inhibitor.Transfusion of 520 ml of the patient’s plasma into a normal subject was followed by a transitory fall of the recipient’s serum factor IX, and a somewhat more prolonged disorder of prothrombin consumption.
The Distribution of Vasculokinase in Human Blood Vessels
Authors: Murray Marvin , Johnson Robert 
Published: July 2018

Summary133 blood vessels were evaluated for vasculokinase concentration in the freshly morbid state. High concentrations of activity were found in the aorta, iliac artery, superior mesenteric artery and popliteal artery. Activity was occasionally found in the inferior vena cava and common iliacs veins. Other vessels evaluated had no activity. Evaluation of the data with respect to vas-culokinase activity and atherosclerosis suggests higher levels of vasculokinase in those vessels having atherosclerosis.
Studies on the In Vivo Behavior of Blood Coagulation Product I in Rats
Authors: Spaet Theodore H 
Published: July 2018

SummaryEvidence is presented in rats that the liver is involved in clearance from the circulation of the coagulant intermediate, product I. Although product I injected into the general circulation failed to elicit the defibrination syndrome, similar injections accompanied by ligation of the hepatic blood supply were followed by a significant drop in plasma fibrinogen. Product I was largely inactivated following perfusion through the liver, but addition of antiheparin drugs to the perfusate prevented this inactivation. No anticoagulant activity could be demonstrated in perfused material. Perfusion through the liver of product I precursors demonstrated inactivation of factor IX but no effect on factors V, VII, VIII, or X.
(Blut-)Gerinnung und Wundverschluß bei Invertebraten
Authors: Lechler E , Gross R 
Published: July 2018

Zusammenfassende DiskussionAußer der Tatsache, daß in allen beschriebenen Tierstämmen Zellen entweder allein oder zusammen mit einem Plasmabestandteil „Gerinnsel” bilden, gibt es keinen Befund zur Gerinnung oder Blutstillung bei Invertebraten, der in allen Stämmen und Klassen übereinstimmend erhoben wurde. Neben der Subjektivität in der Darstellung und Beurteilung (z. B. mikroskopischer Befunde), dem Zustand und Entwicklungsstadium der Versuchstiere und dem verschieden schnellen Ablauf der Gerinnungserscheinungen haben sicherlich die jeweils angewandten Methoden der Blutentnahme und Untersuchung in entscheidendem Maße die Versuchsergebnisse beeinflußt. Bei einer größeren Zahl von Arbeiten handelt es sich nur um die Beschreibung makroskopisch erkennbarer Veränderungen nach Austritt des Blutes bzw. der Körperflüssigkeit. In der Mehrzahl sind die Darstellungen der Gerinnungsverhältnisse aus mikroskopischen Beobachtungen gewonnen, die sich aber in der Technik weitgehend unterscheiden. Beobachtungen eines Bluttropfens auf dem Objektträger, eines hängenden Tropfens (auch in einer feuchten Kammer), eines Blutfilms unter dem Deckglas und eines Bluttropfens, der in Öl eingetaucht ist, sind die am häufigsten angewandten mikroskopischen Untersuchungen, für die das Lichtmikroskop, das Phasenkontrastmikroskop und in einem Fall [Franke (1960)] das Elektronenmikroskop herangezogen wurden. Auf den Einfluß der Methodik auf die Versuchsergebnisse wurde von einigen Autoren immer wieder hingewiesen, zuletzt von Franke (1960), der ein eindrucksvolles Beispiel (Einfluß des pH-Wertes) gibt. Untersuchungsmethoden, die denen der Gerinnungsforschung an Säugetieren entsprechen, wurden bzw. konnten nur bei Arthropoden — und hier wiederum vorwiegend bei Crustaceen — angewandt werden. Die letzteren weisen nicht nur „Gerinnung” eines Plasmabestandteils, sondern vor allem auch ausreichende Blutmengen für solche Untersuchungen auf. Die Blutentnahme bei großen Crustaceen ist relativ leicht, wogegen bei Insekten winzige Ausbeuten und ein intensiver Kontakt mit Wundrändern und fremden Oberflächen nicht zu vermeiden sind. Da eine der wichtigsten Möglichkeiten, den Gerinnungsvorgang zu analysieren, in der Zugabe von Substanzen besteht, deren Wirkung und Eigenschaften bekannt sind (z. B. Inhibitoren der Gerinnung), besteht bei der oft rasch eintretenden Gerinnselbildung die Gefahr, daß zu dem Zeitpunkt, an dem Blut und die zu testenden Substanzen zusammenkommen, die Zell- und Plasmaveränderungen schon so weit fortgeschritten sind, daß eine sichere Beeinflussung nicht mehr zustande kommt.
Autoprothrombin C Activity from Prothrombin with Snake Venom or Trypsin
Authors: Marciniak Ewa , Cole Edmond R , Seegers Walter H 
Published: July 2018

SummarySuitable conditions were found for the generation of autoprothrombin C from purified prothrombin with the use of Russell’s viper venom or trypsin. DEAE chromatographed prothrombin is structurally altered and has never been found to yield autoprothrombin C and also did not yield it when Russell’s viper venom or trypsin were used. Autoprothrombin C is derived from prothrombin with tissue extract thromboplastin, but not in large amounts with the intrinsic clotting factors. With the latter thrombin and autoprothrombin III are the chief activation products. Autoprothrombin III concentrates were prepared from serum and upon activation with 25% sodium citrate solution or with Russell’s viper venom large amounts of autoprothrombin C were obtained, and this was of high specific activity. Theoretically trypsin is not a thrombolytic agent, but on the contrary should lead to intravascular clotting.
Molecular Mechanisms of Mutations in Factor XIII A-subunit Deficiency: In vitro Expression in COS-cells Demonstrates Intracellular Degradation of the Mutant Proteins
Authors: Palotie Aarno , Mikkola Hanna , Muszbek Laszlo , Haramura Gizela , Hämäläinen Eija , Jalanko Anu 
Published: July 2018

SummaryFactor XIII deficiency is an autosomal recessive bleeding disorder that is largely caused by various mutations in FXIII A-subunit gene. Characteristically, the patients lack both A-subunit activity and antigen in the circulation. Here we have analysed the consequences of four mis-sense mutations (Met242→Thr, Arg252→Ile, Arg326→Gln, Leu498 to Pro) and one stop mutation (Arg661→Stop) in the FXIII A-subunit gene by expression in COS-cells. After transient transfection each mutant cDNA expressed mRNA at an equal level to the wild type FXIII. However, the mutant polypeptides accumulated in the cells in significantly reduced quantities and demonstrated only very low enzymatic activity. Analysis of immunoprecipitated metabolically labelled polypeptides demonstrated remarkable instability and intracellular degradation of all mutant FXIII proteins. These results verify the deleterious nature of the individual amino acid changes and confirm that protein instability and susceptibility to proteolysis are consequences of the mutations, as predicted from the three-dimensional model of crystallised FXIII A-subunit.
Inhibition of Thrombin-mediated Cellular Effects by Triabin, a Highly Potent Anion-binding Exosite Thrombin Inhibitor
Authors: Glusa Erika , Bretschneider Ellen , Daum Joachim , Noeske-Jungblut Christiane 
Published: July 2018

SummaryTriabin, a 17 kDa protein from the saliva of the assassin bug Triatoma pallidipennis is a potent thrombin inhibitor interfering with the anion-binding exosite of the enzyme. The recombinant protein, produced by the baculovirus/insect cell system, was used to study the inhibitory effect on thrombin-mediated cellular responses. The thrombin (1 nM)-stimulated aggregation of washed human platelets and the rise in cytoplasmic calcium in platelets were inhibited by triabin at nanomolar concentrations. In contrast, the rise in calcium induced by the thrombin receptor-activating peptide (10 μM) was not suppressed by triabin. In isolated porcine pulmonary arteries, preconstricted with PGF2γ, thrombin (2 nM) elicited an endothelium-dependent relaxation which was inhibited by triabin in the same concentration range as found for the inhibition of platelet aggregation. Higher concentrations of triabin were required to diminish the contractile response of endothelium- denuded pulmonary vessels to thrombin (10 nM). In cultured bovine coronary smooth muscle cells, the mitogenic activity of thrombin (3 nM), measured by [3H]thymidine incorporation, was also suppressed by triabin. In all these assays, the inhibitory effect of triabin was dependent on the thrombin concentration used.These studies suggest that the new anion-binding exosite thrombin inhibitor triabin is one of the most potent inhibitors of thrombin-mediated cellular effects.