bluuebunny/crossref_metadata_2025_split huggingface dataset:
ACTIVE SITE-SELECTIVE LABELING OF THROMBIN WITH FLUORESCENCE PROBES USING THI0ESTER DERIVATIVES OF PEPTIDE-CHL0R0METHYL KETONES
Authors: Bock Paul E 
Published: August 2018

Active site-directed inactivation of a serine protease with a thioester derivative of a peptide-chloromethyl ketone followed by reaction of the unique thiol group generatedin the presence of hydroxylamine with a fluorophore-iodoacetamide hasbeen investigated as a new method for covalent incorporation of extrinsic fluorescence probes into the active sites of blood coagulation proteases. The specificity of labeling by this method was evaluated by quantitation of the reactions between human thrombin, acetylthioacetyl-D-Phe-Pro-ArgCH2Cl (ATA-FPRCK) and 5-iodoacetamidofluorescein(IAF).ATA-FPRCK was synthesized by reaction of FPRCK with succinimidylacetylthioacetate and purified by chromatography on SP-Sephadex and Sephadex G10. Titrations of the loss of thrombin chromogenic substrate activity with ATA-FPRCK were linear, with end points of 1.1-1.2 mol ATA-FPRCK added/mol active sites, consistent with a reaction stoichiometry of 1 and the ∽90% purity of the compound estimated by reverse-phase HPLC.Inactivation of thrombin wasquantitatively correlated with incorporation of the thioester, with a maximum of 1.04 mol/mol active sites.IAF labeling of ATA-FPR-thrombin inthe presence of 0.1M NH20H yielded a maximu of 0.96 mol IAF incorporated/mol active sites in a reaction accompanied by loss of the thiol group. Incorporation of ATA-FPRCK wasdependent on thefunctional thrombin active site, asdemonstrated by less than 4%thioester or IAF incorporation for the enzyme previously inactivated with FPRCK. I conclude that active site-selective fluorescence labelingcan be achieved by the method described here with the advantage of a wide choice in the properties of theprobe incorporated. In addition, a 2.3-fold difference in fluorescenceintensity was observed for 2,6-ANS derivatives of ATA-FPR-thrombin andATA-D-Phe-Phe-Arg-thrombin, indicating that the spectral properties ofenvironmentally sensitive fluorescence probes are influenced by the structure of the peptide inhibitor.Supported in part by a grant from the American National Red Cross.
TRANSMISSION OF HUMAN IMMUNODEFICIENCY VIRUS INFECTION TO HOUSEHOLD CONTACTS OF PERSONS WITH CONGENITAL HEMATOLOGIC DISORDERS
Authors: Lusher J M , Aledort L M , Hiltgartner M , Mosley J , Operskalski E 
Published: August 2018

The Transfusion Safety Study is collecting data concerning the transmission of transfusion-acquired infections from patients with congenital hematologic disorders to household members. Of 233 patients for whom information is presently available, 128 (55%) were anti-HIV-positive. The 128 positive patients lived in 123 households with 174 members; 16 contacts were positive by EIA and immunoblot.These data provide further evidence of relatively high risk of HIV infection of sexual contacts. The three anti-HIV-positive children are all infants born to anti-HIV-positive wivesof infected hemophiliacs. Passively acquired antibody has not been excluded for two; the third was positive at ten months of age. Thus, vertical transmission may be a very important mechanism of perpetuating the HIV reservoir.
EVALUATION OF HIV ANTIGEN AND ANTIBODIES TO p24 AND gp41 IN HEMOPHILIACS
Authors: Laurian Y , Allain J P , Verroust F , Leuther M , Lambert T , Larrieu M J 
Published: August 2018

Two hundred and seventeen hemophiliacs, known to be HIV seropositive for at least one year, were tested for HIV antigen (HIV Ag) and antibodies to p24 (p24 Ab) and gp41 (gp41 Ab) in 1986. HIV Ag was measured using a sandwich-type immunoassay (Abbott Laboratories); this assay predominantly detects core antigen, with a sensitivity of 30 to 50 pg/ml. Antibodies to p24 and gp41 were titrated with separate competitive immunoassays using recombinant antigens (Abbott Laboratories); reciprocal titers were calculated by comparison to a reference curve obtained by serial dilutions of a standard antibody containing sample. Forty-seven of these 217 patients (21.6 96) are HIV Ag positive, with an undetectable or low titer of p24 Ab in most of them. The rest (170) of the patients are HIV antigen negative ; some of them also have a low titer of p24 Ab. All the patients have a high titer of gp41 Ab. The year of seroconversion to HIV is known for 106 patients. Eighty seroconverted between 1983 and 1985 ; 14 of them (17.5%) are HIV Ag positive (3 had clinical symptoms related to HIV infection, but none developed AIDS); 66 are HIV Ag negative (16 developed clinical symptoms, but no AIDS was observed). Twenty six patients seroconverted between 1979 and 1982 ; 12 of them (46 %) are HIV Ag positive ; 14 patients are HIV Ag negative with low (7 cases) or high (7 cases) p24 Ab titers. The table summarizes the clinical data of these 26 patients.In conclusion, HIV antigen and antibody titer to p24 may be of predictive value in the definition of lower or higher risk of developing clinical complications related to HIV infection.
ENDOTOXIN INDUCES DIC BY BOTH TISSUE FACTOR (TF) AND PLASMINOGEN ACTIVATOR-INHIBITOR (PA-l) SECRETION
Authors: Baldus B , Gehrmann G , Witt W , Donner P 
Published: August 2018

DIC-induced organ failure represents a major pathomecha-nism in endotoxemia. To investigate which components of the haemostatic system may be disturbed during endotoxemia anaesthetized male Wistar rats were injected with E. coli endotoxin at dosages of 1 ng/kg to 100 pg/kg body mass. Citrated blood samples were investigated for fibrinolytic activity by a dilute blood clot-lysis time assay (DBC-LT), for PA-I activity by a new Tunctional assay using immobilized rt-PA on 96-well microtiter plates and for TF activity by measuring the rate of thrombin formation after stimulation with a 2000-fold diluted thrombo plastin reagent.Endotoxin induced a decrease in fibrinolytic activity measured as a prolongation of the DBC-LT at dosages from 75 ng/kg to 100 μg/kg. This effect appeared 2 h after the treatment with endotoxin and persisted for<3 h. In parallel, an increase (up to 7-fold compared to baseline values) in PA-I activity could be measured 2 h after endotoxin application. When the plasma samples were clotted either by kaolin-phospholipid reagent, thrombin or reptilase in the resulting serum PA-I activity was more than 50-fold versus baseline. TF activity generated after stimulation with diluted thromboplastin reagent increased to about 5-fold compared to baseline values. This effect was already significant 1 h after endotoxin injection.The results of this study indicate, that endotoxin induces a destruction of the balance of the haemostatic system by increasing coagulability via stimulation of TF activity and by decreasing fibrinolytic activity by secretion of PA-I. Furthermore the present data provide evidence for activation of a latent form of PA-I during the clotting process.
MINI PLASMINOGEN-LIKE MOLECULE IN SEPTIC PATIENTS
Authors: Kodrich L , Porterie P , Lago O , Bergonzelli G , Sassetti B , Sanchez avalos J C 
Published: August 2018

We have previously described (Thromb.Res.44(6),1986) an altered relation Plasminogen (Pig)/α2~antiplasmin (APL) (Plg/APL<0.6) in the plasma of septic patients. A probable explanation of the mechanism whereby this alteration takes place would be the degradation of Pig to fragments of lower molecular weight due to the action of leukocyte elastase.In order to confirm this we studied 10 patients with sepsis, which did not have clinicalorlaboratory evidence of disseminated intravascular coagulation or septic shock, with positive blood cultures for bacterial germs .Elastase-α1proteinase inhibitor complexes were measured by an enzyme-linked immunosorbent assay (mean:510±181.9ug/l;normal range:86±28.5ug/l). Pig and APL functional activities were assayed by the amidolytic method; Pig: 40±8.9%; normal range: 100±20% .APL: 95±10.1% formal range 100+20%. Two different behaviors were observed in the plasma Pig of these patients with regard to their capacity to bind to Lysi-ne-Sepharose 4B.0n the basis of this observation the patients were divided into two group.Group A(4 patients) only presented Pig activity in fraction 1 (Pig without lysine binding sites : LBS). Group B (6 patients) presented Pig activity in fraction 1 and in fraction 2 (Pig with LBS).The normal controls presented Pig activity only in fraction 2. All the fractions which presented functional Pig activity also presented immunologic Pig activity and developed areas of lysis in heated fibrin plates after activation with urokinaseIt seems tenable the hypothesis that the action of the leukocyte elastase is responsible for the degradation of Pig and this modification in the molecule would give rise to a greater depuration thus explaining the marked drop of the plasmatic levels seen in septic patients.
FIBRINOGENS KYOTO AND TOCHIGI, EACH WITH AN APPARENT ABNORMAL MOL. WT. γ CHAIN, ARE CHARACTERIZED BY REPLACEMENT OF γ ASN-308 BY LYS AND γ ARG-275 BY CYS, RESPECTIVELY
Authors: Yoshida N , Terukina S , Matsuda M , Moroi M , Okuma M , Aoki N 
Published: August 2018

Congenital inherited abnormal fibrinogens (Fbgs) Kyoto and Tochigi showed prolonged thrombin- and reptilase-time, normal release of fibrinopeptides A and B, normal cross linking ability and impaired polymerization of the fibrin monomer.Purified Fbg analyzed on SDS-PAGE under the reduced condition in the system of Laemmli contained 50 % of an apparent lower mol. wt. γ chain (γ Kyoto)(mol. wt.= 48,000 compared with 50,000 for the normal) in Fbg Kyoto and an apparent higher mol. wt. γ chain (γ Tochigi)(mol. wt.= 50,500) in Fbg Tochigi. Apparent mol. wt. differences were also detected in reduced and carboxymethyl ated Fbg, Fbg fragment D1, and D2, but not in D3. This suggested that the abnormality of γ chains in both Fbgs is in γ 303-356.Amino acid sequence analysis was performed for CNBr- or lysylendopeptidase-digested peptides of the γ chain or D1 peptides after fractionation on HPLC. In Fbg Kyoto, γ Asn-308 was substituted by Lys, and a deletion of short peptides corresponding to the mol. wt. difference of 2,000 could not be detected. In Fbg Tochigi, γ Arg-275 was substituted by Cys, and no abnormality of amino acid sequence was found in γ 303-356.These results suggest that some lesions or conformations containing γ 275 and γ 308 will directly or indirectly affect polymerization of fibrin monomers. Although the reason for apparent mol. wt. differences is not known yet, SDS-PAGE in the system of Laemmli will be useful for the analysis of abnormal Fbgs.Fbg Kyoto could not be separated into two or three populations and may contain hetero-dimer molecules, but Fbg Tochigi had unclottable Fbg with predominant γ Tochigi and may contain abnormal homo-dimer molecules and normal molecules.
CONCENTRATED DDAVP: FURTHER IMPROVEMENT FOR THE TREATMENT OF MILD F.VIII DEFICIENCIES
Authors: Ghirardini A , DiPaolantonio T , Solinas S , Papacchini M , Cutrera C , Mariani G 
Published: August 2018

We have evaluated the pharmacological efficacy of a concentrated DDAVP preparation (40 μg/mL) (herein referred to as C-DDAVP) administered subcutaneously (s.c.) in mild (n=23) and moderate (n=2) hemophilia A patients. A comparison between the response to s.c. C-DDAVP and the "dilute" DDAVP (4 μg/ml) (administered s.c. in 16 patients with mild (n=13) and moderate (n=3) hemophilia A and i.v. in 18 patients with mild (n=16) and moderate (n=2) was also carried out. In all instances Desmopressin was given at a dose of 0.3 μg/kg b.w. in absence of bleeding. The increase of F. VIII:C (expressed as post/pre ratio) after s.c. C-DDAVP was 2,55 at 30', 3,50 at 60'and 3,21 at 120'. The comparison among the three schedules of DDAVP administration showed that s.c. C-DDAVP elicited an increase of F. VIII :C at least as high as that induced by the dilute DDAVP with differences not statistically significant.C-DDAVP was also administered s.c. in 4 patients with type I vWD (platelet normal subtype) with a normalization of bleeding time 60' after s.c. C-DDAVP, concomitant with a rise of activities related to F. VIII/vWF complex. Side effects were modest and transient. We can conclude that s.c. C-DDAVP is equally effective and safe in comparison with the dilute brand with the advantage of the minimal adminstration volume (<1 mL).
THE EFFECT OF DDAVP ON PLASMA AND PLATELET VON WILLEBRAND FACTOR MULTIMERIC PATTERN AND BLEEDING TIME IN PATIENTS WITH CONGENITAL PLATELET FUNCTION DEFECTS
Authors: Oksanen K , Kekomäki R , Lindbom A , Myllylä G , Rasi V , Vahtera E 
Published: August 2018

Eleven patients with congenital platelet function defects and prolonged template bleeding time (BT) were studied. All patients had significant bleeding tendencies and were classified as having platelet release defects.After initial blood sampling and BT measurement, tranexamic acid ( 10 mg/kg ) and DDAVP ( 0.3 ug/kg over 15 minutes ) were infused, followed by second blood sampling at, 30 minutes and BT measurement at 60 minutes.Plasma vWF multimeric patterns were analyzed from 11 and platelet vWF multimeric patterns from 7 patients. vWF multimers were identified by electrophoresis of plasma or platelet lysates in agarose containing 0.1% SDS and visualized by immunoblotting using alkaline phosphatase-conjugated anti-antibody.Bleeding time was normalized by DDAVP in 5 patients, partly corrected in 3, and unchanged in 3. Those 4 patients with longest BT ( more than 20 minutes ) either showed no response (3) or were only partially corrected (1).Plasma F VIII:c, vWf:Ag, and F VIII:Rcof all increased similarly in responders, partial responders, or non-responders. The multimeric patterns of plasma vWF were initially normal in all patients and showed increases of the largest multimers in all three groups. Platelet vWF analysis also showed increase of larger multimers after DDAVP infusion; these changes usually parallelled those of plasma vWF. Increase of the large multimers was observed as well in responders and partial responders as in non-responders.DDAVP was effective in correcting the prolonged bleeding time of several patients with platelet release defect. The analysis of plasma or platelet vWF multimeric pattern seemed not to predict this response.
UREMIC PLASMA, AFTER INFUSION OF DESMOPRESSIN, IMPROVES THE INTERACTION OF NORMAL PLATELETS WITH VESSEL SUBENDOTHELIUM
Authors: Castillo R , Escolar G , Monteagudo J , Cases A , Garrido M , Ordinas A 
Published: August 2018

Desmopressin (DDAVP) shortened the bleeding time and increased the platelet retention on glass beads and the platelet interaction on subendothelium measured by the Baumgartner perfusion system in 11 uremic patients in whom the three tests were abnormal previous to the treatment (1).Patients were chosen at random out of a group of 30 with prolonged bleeding time and decreased platelet retention on glass beads. All tests were performed on blood drawn before and one and six hours after a single dose of DDAVP (0.4 μg/kg body weight). Perfusion experiments were carried out at a shear rate of 800 sec-1.Levels of VIII:C, VIIIR:Ag and RiCof were at the upper limit of normality before DDAVP and significantly increased one hour after treatment. The multimeric structure of vWF in pretreatment plasma was normal ; one hour after DDAVP larger multimers appeared.After injection of DDAVP, the perfusion studies using reconstituted blood with uremic PPP in presence of isolated normal platelets and washed red cells, showed a statistically increased surface coverage and platelet aggregate formation on subendothelium (p < 0.05 respectively when compared to the pretreatment values). In the same perfusion assays, the in vitro addition to pretreatment plasmas of 1 u/ml of purified vWF with normal multimeric structure, or purified VIII:C and vWF (1 u/ml each) did not modify the decreased platelet interaction on subendothelium.These results confirm the shortening of bleeding time by DDAVP in uremic patients and reveal an increase of platelet interaction on vessel subendothelium mediated by a factor present in PPP. Besides, they show that the effect of DDAVP in these patients is not due to the quantitative increase of the plasmatic vWF and FVIII.(1) Blood, 68, 2:337-342, 1986.
HUMAN RECOMBINANT ERYTHROPOIETIN (rHuEpo) CORRECTS ANEMIA AND SHORTENS THE BLEEDING TIME (BT) IN UREMIC PATIENTS
Authors: Moia M , Casati S , Della Valle P , Passerini P , Ponticelli C , Mannucci P M 
Published: August 2018

A hemorrhagic tendency and anemia are two major complications of uremia. There is a significant negative correlation between BT and hematocrit (Ht) in uremic patients. We studied the efficacy of rHuEpo in correcting both these abnormalities in 10 patients on chronic hemodialysis with severe anemia (basal Hb levels 6.2±0.8 g/dL). Seven patients had BT longer than 10 min., 5 had BT longer than 30 min. rHuEpo was given to the patients 3 times a week at increasing doses, from 24 U/Kg to a maximum of 432 U/Kg, aiming to reach Hb levels ⪖12 g/dL. BT was measured (with the template-like disposable device Simplate II) before starting rHuEpo therapy and after reaching the target Hb values. One patient (n° 6) was excluded from the study after 5 weeks of rHuEpo treatment because of development of an arterio-venous fistula thrombosis. The data are shown in the table.Eight of the 9 patients who concluded the study had final BT shorter than 10 min. This demonstrates the efficacy of rHuEpo in correcting both anemia and prolonged BT in uremic patients.
ANALYSIS OF PATIENTS WITH A PROLONGED BLEEDING TIME
Authors: Nieuwenhuis H K , Zwaginga J J , Sixma J J 
Published: August 2018

The bleeding time (BT) is one of the most important screening tests in patients with a bleeding tendency. Investigations of Von Willebrand Factor and aggregation tests form routine diagnostic tools to analyse a prolonged BT. In many patients, however, this approach fails to explain the bleeding tendency because no abnormality is found. In order to deal with this problem , we chose three methods: I) determination of platelet nucleotides and serotonin in all patients with a prolonged BT, independent of the results of aggregation tests, II) measurement of platelet adherence to purified collagen and the matrix of endothelial cells in a perfusion system, III) measurement of adherence of normal blood to matrix of patients' fibroblasts. I) In a group of 145 patients with a prolonged BT and a normal platelet count the diagnosis von Willebrand1's disease was made in 52 patients (36%), congenital Storage Pool Disease (SPD) in 27 pts (18%), defect of thromboxane synthesis in 4 pts (3%) and platelet function disorders with miscellaneous aggregation abnormalities in 23 pts (16%). No abnormalities were found in 39 pts (27%). Analysis of aggregation tests, disclosed normal aggregation tracings in many patients with SPD: 23% of 106 patients with congenital or acquired SPD had normal aggregation tests.Adhesion studies were performed with the blood of 7 patients with an unexplained prolonged bleeding time. Two patients had a severe defect and one patient a mild defect of adherence. Further studies revealed the presence of an autoantibody on the platelets in one of these patients.In order to diagnose vessel wall defects which may cause a prolonged BT, we studied the adherence of normal blood to the matrix of the fibroblasts of one patient. We found a decreased adherence, which suggests the presence of a vessel wall defect causing a prolonged BT.We conclude that in many patients with a prolonged BT and normal VWF parameters and normal aggregation tests, SPD or adhesion defects may be responsible for a bleeding tendency.
STUDIES ON PLATELET AGGREGATION BY IMPEDANCE AGGREGOMETRY AND ATP SECRETION IN NON-ANTICOAGULANT BLOOD
Authors: Heptner W , Suárez J R , Lütgendorf V 
Published: August 2018

Investigations in vitro on the time-dependent increase in thrombin activityand platelet function have been used tocharacterize the kinetics of the clotting process in nonanticoagulated blood. The test procedures described involve great effort and expense and therefore are not suitable for routine tests in pharmacology and clinical pharmacology. The present contribution describes the determination of clotting times in ATP secretion in the Chrono-Log Whole Blood Aggregometer.Blood was taken from healthy donors who had not used any drug in the two weeks before the trial. 0.5 ml blood wereimmediately transfered into siliconizedglass cuvettes containing 0.4 ml salineand 0.1 ml luciferin-luciferase cocktail prewarmed to 37°C. Impedance and luminescence were recorded continuously. Clotting at the electrodes is indicated by an immediate steep rise in both impedance and luminescence. Clotting time is defined as the time from diluting the blood in the cuvettes until the point at which marked elevation of these variables begins.In the blood of twelve subjects the mean clotting time was 3.8 min and intersubject variation (SD) was 0.45 min. Drastic interindividual differences in response to collagen and ADP in citratedwhole blood were observed in the study group.In vitro addition of 20 μl Fibraccel(Behringwerke AG, Marburg, FRG),a platelet factor 3 containing plateletextract decreased clotting time by 35 %(n=10). In the presence of 0.2 U heparin a slow and lona-lasting increase in impedance was seen. 1 g oral AspirinR didnot influence clotting time measured ex vivo.The results indicate that whole blood aggregometry is a simple, fast, and precise method of determining blood clotting and the effects of drugs in a medium reflecting almost physiological conditions.
IMPORTANCE OF SOME MOLECULAR MARKERS OF HEMOSTATIC ACTIVATION FOR THE DIAGNOSIS, THE CHOICE AND THE CONTROL OF PREVENTIVE AND CURATIVE THERAPY OF D.V.T. AND P.P.S
Authors: Moriau M , Col-De Beys Ch , Golinska B , Lavenne-Pardonge E 
Published: August 2018

The measurement, before and after treatment, of some molecular markers of hemostatic activation (βTG, PF4, TXB2, FPA, 6 keto PGFlα) and the determination of their increased coefficient ratio (Δ+/βTG/Δ+Δ FPA, 4+βTG/4+ PF4,4+ 6 keto PGF1α/Δ+ TXB2 combined with the estimation of other parameters (F.VIII:Ċ/F.VIIIR:AG), AT III, PROT. C, ELT with and without ischemia) permlted us to subdivide the deep venous thromboses in two groupsThe first one or "simple D.V.T." was observed in normal subjects with or without varicoses, and without other main pathology and was consecutive to a simple plasma factors activation, the second one or "complicated D.V.T." appeared in patients with other pathology (infections, neoplasms, trauma, metabolic disorders) and was consecutive to a combined activation of plasma factors and plateletsA:before treat.,B:after anticoagul.,C:after anticoagul. + platelet inhibitors / * extreme values (MV ±2ŊIf anticoagulants (Heparine ancjfor VKA) alone were effective and sufficient for the treatment of "simple DVT" they were little or non active in the "complicated" forms and must be combined with platelet inhibitors to give the same result. The prevention of DVT in venous insuffisancy, consecutive or not to DVT, must be performed in the same way. A comparative study with various types of platelet inhibitors permited us to establish a scale of activity and to observe a benefic synergism with some combinations