bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE DISTRIBUTION OF CROSS-LINKED FIBRIN IN HUMAN LUNG CARCINOMA PARALLELS THAT OF ACTIVATED HOST MONONUCLEAR LEUKOCYTES: IMMUNO-HISTOLOGIC STUDIES WITH MONOCLONAL ANTIBODIES
Authors: Rickles F R , Hancock W W , Kobzik K , Hogg N , O’Hara C 
Published: August 2018

Previous immunohistologic studies of human lung carcinoma, using polyclonal antibodies to antigens shared between fibrinogen (FGN) and fibrin (FB), showed that FGN/FB were associated withtumor cells. These findings were interpreted as evidence of the presence of tumor-associated procoagulant activity(PCA). Wecompared the distribution of coagulation-associated proteins in 16 casesof human carcinoma of the lungofvarying histologic types, using polyclonal antibodies to FGN/FB and monoclonal antibodies (mAb) to cross-linked fibrin (XL-FB;UC-45), fibronectin (FN;PHM13), factor VIII (vWF:Ag)and a tissue factor-related antigen(TF:RAg;A1 -3)- Host mononuclear leukocytes were identifiedusing various mAb toT cells and macrophages, and studied for their expression of receptorsfor interleukin-2 (IL-2R). Positive resultsare summarizedIn addition, studies of the mononuclearcells adjacent to tumors in 12/12 casesshowed the presence of tumor-associated macrophages, 10/11 showed T cells,mainly T8+, and A/5 showed corresponding expression of IL-2R, suggesting cell activation.The use of highly specific mAb showed that XL-FB is actually more selectively distributed than is found using polyclonal antisera to FGN/FB, and indeed XL-FB was largely confined to those areas adjacent to tumors which are rich in mononuclearcells. These findings suggest that fibrin deposits in human carcinomasof the lung may be due todevelopment of PCA by activated host mononuclear cells, rather than tumor cells.This lack of XL-FB on tumor cellsinspite of A1- 3 binding suggests that TF:RAg may not be available on the tumor cell surface for the activation of clotting. Further studies are neededto define the functional capacity of PCA molecules on tumor cells and tumor-associated mononuclear cells in situ.
COAGULATION ACTIVATION AND OCCURRENCE OF HYPOFIBRINOGENEMIA IN PATIENTS WITH ACUTE NONLYMPHOBLASTIC LEUKEMIA
Authors: Pabinger I , Lechner K T , Bettelheim P , Dudczak R , Hinterberger W , Korninger C , Medicine I Int 
Published: August 2018

122 consecutive adult patients (pts) with acute nonlympho-blastic leukemia (ANLL) were studied for evidence of coagulation activation andoccurrence of hypofibrinogenemia. In 16 pts (13%) decreased fibrinogenlevels (< 1.5g/l) were found.Data on fibrinopeptide A levels (FPA), ethanol gelation test (EGT) andfibrin(ogen) degredation products(FDP) are listed in the table:The occurrence of hypofibrinogenemia was not correlated to the peripheral blast cell count. 10/18 pts with M3 (FAB-classifica-tion), 2/46pts with M2, 2/25 pts with M4 and 2/14 pts with M5 leukemia developed hypofibrinogenemia. Early death occurred in 31% of pts with hypofibrinogenemia (in most pts due to hemorrhage) and only in 10% without (in most pts due to septicemia). No significant difference in remission duration was found between the 2 groups. 48 patients were reinvestigated at the time of recurrence of disease. 5 of 7 patients with and 38 of 41 patients without initial hypofibrinogenemia had a coagulation pattern similar to the one observed at first presentation.The following conclusions can bedrawn:(1) In most patients with ANLL there is evidence of coagulation activation. (2) Hypofibrinogenemia in patients with ANLL appears to bethrombin mediated. Therefore the term disseminated intravascular coagulation (DIC) may be used. (3) DIC is strongly associated with the subtype M3 (promyelocytic L), but may as well occur in other ANLL subtypes.(4) The presence of DIC seems to be a specific property of certain leukemic clones. This assumption is supported by the coagulation studiesduring recurrence of ANLL. (5) Patients with low fibrinogen levels areat high risk of early death due to hemorrhagic complications.
Increase of Thrombin-Antithrombin III (TAT) Complex Plasma Levels in Thromboembolic Diseases during Thrombolysis
Authors: Seitz R , Pratorius G , Blanke R , Strauer B B 
Published: August 2018

Recently an enzyme immuno assay of thrombin-antithrombinlll complex (TAT) plasma levels was developed by PELZER et al. (Thromb. Haemost. 54:24,1985). This test appears to be useful in the detection of intravasal thrombin generation, since all of 17 patients (pts.) with pulmonary embolism and 15 of 16 pts. with deep vein thrombosis (DVT) showed elevated values above 3 ng/ml.In 9 pts. with acute myocardial infarction (AMI) the TAT levels increased significantly (p 0.001) 3 to 6 hours after thrombolytic therapy with 1.5 million units streptokinase (SK) over 30 minutes. A concomitant increase of fibrinopeptide A (FPA) levels (p=0.048) was observed. In contrast, 8 AMI pts. treated with heparin showed an insignificant increase of TAT and FPA. In 7 DVT pts. the TAT levels rose significantly (p 0.001) within 6 hours after start of urokinase (UK) infusion, while the FPA levels were enhanced prior to treatment and showed no further increase.In order to assess the in vitro effects of SK and UK on TAT levels, clots obtained by recalcification of citrated plasma were incubated in heparin (2 units/ml) plasma. An increase of TAT occurred after addition of SK or UK, which was less pronounced when the clots were rinsed extensivly or squeezed before incubation. When SK or UK were added to plasma in the absence of a clot, still a small increase of TAT occurred which was absent in saline controls.The data suggest that SK and UK action is associated with the generation of TAT complexes. In vivo, thrombin or thromboplastic material might be released by enhanced "wash out" from the recanalized coronary artery or from the reperfused in-farcted myocardium. Thrombin might also be released from binding sites on fibrin clots or fibrinogen. It is conceivable that these findings contribute to the understanding of reocclusion of infarct vessels after thrombolytic therapy. This points to the importance of careful anticoagulation in patients receiving thrombolytic therapy.
THE PHYSIOLOGICAL ANTITHROMBIN (BETA) VARIANT WITH INCREASED HEPARIN AFFINITY LACKS CARBOHYDRATE AT ASN 135
Authors: Brennan S O , George P M , Carrel R W , Jordan R 
Published: August 2018

Some 10% of the antithrombin fromnormal human plasma can be isolated onthe basis of its higher affinity forheparin Sepharose. Not only does this ATIII beta have a higher heparinaffinity, but it is also less negatively charged and has a lower molecular weight than normal AT-III alpha.Neuraminidase and Endo F treatment suggest the loss of a single carbohydrate sidechain from beta AT-III (Peterson and Blackburn. J Biol Chem 1985,260, 610)Antithrombin has a single polypeptide chain with biantennary carbohydrate attachment sites at asparagines 96, 135, 155 and 172. The 25 kDA CNBr fragment of AT-III alpha (residues 104-251) runs at 22.5kDa in the case of AT-III beta yet they have the same N and C-terminal sequence. Tryptic peptide maps of theseCNBr fragments showed that a single neutral (glyco) peptide, Lys-Ala-Asn⋆-Lys was missing from AT-III beta and replaced by twobasic peptides, Lys, Ala, Asn, Lys and Ala, Asn, Lys; indicating the absence of an oligosaccharide sidechainon asparagine 135. This was confirmed by chromatography of tryptic peptides on Con A-Sepharose followed by mapping of the bound and unbound fractions. There were two new unbound peptides (Lys, Ala, Asn, Lys and Ala, Asn, Lys) in AT-III beta. The corresponding peptide Lys-Ala-Asn⋆-Lys was the only peptide missing from the bound glycopeptide fraction.The absence of carbohydrate at Asn 135 explains the increased heparinaffinity of beta AT-III as on the molecular model this oligosaccharide forms a negative and bulky shell on the perimeter of the positive bindingsite centred on Arg 47.Whether the loss of the sidechain is due to circulatory removal is not known but a recent variant identification confirmsthat it may alternatively be due to failure of attachment at the time ofsynthesis. Potentially the loss or modification of oligosaccharide 135 provides another level of control of coagulation by altering the avidity of AT-III for thrombin when heparin activation is suboptimal.
INHERITED DEFICIENCIESCAN AFFECT SEPARATELY THE PLATELET MEMBRANE GLYCOPROTEIN Ilb-IIIa COMPLEX AND THE LEUKOCYTE LFA-1, Mac-1 and pl50,95 COMPLEXES
Authors: Pidard D , Fischer A , Bouillot C , Ledeist F , Nurden A T 
Published: August 2018

The human platelet membrane glycoprotein (GP) IIb-IIIa complex and a family of functional leukocyte cell membrane antigens, LFA-1 (L), Mac-1 (M) andpl50,95 (X), possess knownstructural analogies. Similaritiesinclude a heterodimeric structure with a high mol. wt. αsubunit (Mr∽ 145-180 kDa) , associated nonconvalently with a lower mol. wt.β-subunit (Mr ∽ 90-95 kDa),anda partial amino acid sequence hommology between GP lib and αL or CKM. Furthermore, GP lib, α L and αM were reported to be co-expressed in murine cells transfected with a 20 kilobase human DNA fragment.To address the question of a possible genomic linkage between these related glycoproteins of different cells, we have examined patients with either ‘LFA-1 immunodeficiency disease’ or with Glanzmann's thrombasthenia (GT). S.Bo. and P.Ce. are children affected by recurrent bacterial infections since birth. Cytofluorimetric analysis using monoclonal antibodies (MAbs) for the αL, αM,αX and β subunits demonstrated that the surface expression of LFA-1, Mac-1 and pl50,95 intheir leukocytes was ≤1% of the normal values. Platelets from both patients aggregated normally and readily bound the MAbs AP-2 (anti-GP IIb-IIIa) or Tab (anti-GP IIb). Crossed immunoelectrophoresis confirmed the presenceof GP IIb-IIIa complexes, whileSDS-polyacrylamide gel electrophoresis showed a normal migration of GP IIb and GP IIIa. Patients C. Bl. and M.Ca.are typical of the type I subgroupofGT. Their platelets are unable toaggregate and contain < 1% of the normal platelet content of GP liband GP Ilia.Cytofluoro-graphy showed a normal expression of LFA-1, Mac-1 and 150,95 on the surface of lymphocytes, polymorphonuclear cells and/or monocytes of both patients. Our data thus show that despite sequence homologies and a potential genomic linkage, the cellular expression of the platelet GP IIb-IIIa complex and of the LFA-1 related leukocyte antigens may be dissociated in genetic disorders where anabnormal glycoprotein distribution may be restricted to one type of cell.
DIFFERENTIAL EXPRESSION AND SUBCELLULAR LOCALIZATION OF TISSUE FACTORIN A CONSTITUTIVE VERSUS AN INDUCIBLE CELL TYPE
Authors: Morrissey J H , Gregory S A , Edgington T S 
Published: August 2018

Tissue factor (TF) is an integral membraneglycoprotein and receptor present on a variety of cells outside of the vasculature, but normally absent from intravascular cells. TF plays a central role in initiation of coagulation by rapidly binding and allosterically activating bound factor Vll/VIIa, which proteoly-tically activates coagulation factors IX and X. This protease cascade appears to play a role in the cellular inflammatory response, during which endothelial cells and monocytes/macrophages can be induced to express cell surface TF.Monocyte TF can be induced in response to endotoxin and also via direct interaction with activated T cells and by a specific lymphokine.We have developed a panel of polyclonaland twenty-nine high affinity monoclonal antibodies to human TF. The antibodies recognize TF epitopes under a broad range of conditions, some of which rapidly and efficiently neutralize <95% of TF activity isolated from brain, placenta and expressed bycultured cells. Using these antibodies in immunohistochemical assays, we haveobserved little or no TF antigen cytologically associated with resting monocytes, noTF activity, and following stimulation, the cytologic appearance of TF antigen parallels the acquisition of TF activity.Immunohistochemical staining of stimulated monocytesis diffuse, consistent with homogeneous cell-surface distribution of the TF molecule.In addition, the normal human fibroblastic cell lines GM1380 and GM1381, whichexpress TF const itutively, show a cytologically different and much more intense pattern of intracellular inclusions of TF. This is consistent with previous observationsthat lysed cells show about five-fold moreTF activity than do intact cells. These findings indicate the presence of an intracellular storage site for TF in some cell types, a pattern presently associated only with constitutive expression of this receptor protein. In addition, they confirm thatTF is induced in stimulated monocytes rather than translocation or modification. Supported by NIH grants HL-16411 and CA-41085.
RELATIONSHIP BETWEEN BLEEDING EVENTS AND CHANGES IN PLASMA IN PATIENTS TREATED WITH RECOMBINANT TISSUE PLASMINOGEN ACTIVATOR AND STREPTOKINASE IN TIMI STUDY-PHASE I
Authors: Rao MD A K 
Published: August 2018

In Thrombolysis in Myocardial Infarction (TIMI) trial (Phase I) patients were randomized to receive intravenously either 80 mg of predominantly double~chain (G11021) recombinanttissue plasminogen activator(rt-PA) over 3 hrsor 1.5 million units of streptokinase (SK) over 60 min. All patients received an intravenous heparin bolus (5000 units) prior to angiography and a continuous infusion (1000 units/hr) starting 3 hr later.Bleeding occurred in 33% (rt-PA) and 31% (SK)of patients; over 70% of episodes were at vascular puncture sites. We report here the relationship between bleeding events and changes in plasma fibrinogen (FBG), plasminogen (PMG),and fibrin(ogen) degradation products (FDP) at 5 hr after initiation of drug infusion.Shown are number of patients with hemorrhage, total number of patients,and correlation coefficients (r) for occurrence of bleeding versus the changes in plasm proteins in each group.The data indicate a relationship between bleeding events and changes in plasma proteins,with higher frequency of bleeding in patients with greater changes. FDP levels in both groups show a correlation with bleeding unlikely due to chance alone. While the hemorrhage may be due to multiple factors such as vigorous anticoagulation, arterial punctures, and platelet inhibition, the above findings suggestthat the plasma changes contribute to the hemorrhagic events.
THE EFFECT OF A COMBINED TXA2SYNTHETASE AND TXA2/PROSTAGLANDIN ENDOPEROXIDE RECEPTOR BLOCKER(R 68 070)ON THE ACTIVATION OF EXCITATORY RECEPTOR-COUPLEDPHOSPHOLIPASE C IN HUMAN PLATELETS
Authors: De Chaffoy de Courcells D , De Clerck F 
Published: August 2018

Prostaglandin endoperoxides (PGEND) and thromboxane A2 (TxA2)contribute to the activation of platelets, involving inositol-containing phospholipids as a signal transducing system. A primary step in this signal transduction consists of the activation of phospholipase C, which then yields diacylglycerol and inositol phosphates;diacylglycerol is subsequently phosphorylated to phosphatidic acid (PA). In platelets prelabelled with [32P] orthophosphate,receptor activation is quantitatively reflected by an increased formation of [32P]-PA.Using this assay, the relativeimportance of endogenously generated PGEND and TxA2 for the subsequent PA-formation was analysed by means of pharmacological manipulations. R 68 070, an oxime-alkanecarboxylic acid derivative combining specific TxA2 synthetase inhibition with TxA2/PGEND receptor blockade in one molecule (1 x 10-6M) inhibited the formation of PA in collagen-stimulated platelets; by contrast, synthetase inhibitors without receptor effect (da-zoxiben, OKY-1581,1x 10-6M) increased the PA-response tocollagen.Using U 46619 as a stimulus, R 68 070 as well as BM 13177, a receptor blocker withouteffect on synthetase (1 x 10-6 M)both reduced the PA-response to the same extent while OKY-1581 (1 x 10-6 M) was ineffective. The phospholipid response induced by serotonin, vasopressin or PAF were not affected by R 68 070, demonstrating its specificity for the prostanoid system.From these data we suggest that selectiveinhibition of TxA2 synthetase does not prevent activation of excitatory platelet receptors for arachidonate metabolites. Effectiveness was only obtained by combined TxA2 synthetase/PGEND receptor blockade.
TISSUE PLASMINOGEN ACTIVATOR INHIBITS THROMBIN-INDUCED AGGREGATION AND SHAPE CHANGE,BUT FACILITATES SECRETION,IN GEL-FILTERED PLATELETS ONLY
Authors: Blockmans D , Houtte E Van , Arnout J , Mombaerts P , Collen D , Vermylen J 
Published: August 2018

Prolonged administration of tissue plasminogen activator (t-PA) has caused bleeding problems in some patients, that did not necessarily correlate with a significant drop of fibrinogen levels. We have therefore evaluated the effect of t-PA on platelet function in vitro.Incubation of gel-filtered platelets for one hour at 37°C with 180 μg/ml plasminogen and increasing concentrations of t-P(50-1600 ng/ml) significantly inhibited shapechange and aggregation induced by thrombinand the thromboxane mimetic U 46619 in a dose-dependent manner. In an EDTA milieu, whichbolishes aggregation, a dual effect of t-PA and plasminogen was observed in the aggregometer: the thrombin- or U 46619-elicited initial decrease in light transmission, reflectingthe disc-to-sphere transformation of platelets, was almost completely inhibited from 50 ng/ml t-PA upwards; the subsequent increase in light transmission, reflecting granule secretion, was however enhanced by small amounts of t-PA (up to 200 ng/ml). The latter finding was confirmed by direct measurement of secreted ATP:t-PA atconcentrations up to 200ng/ml enhanced thrombin- or U 46619-in-duced secretion. The amount of plasmin generated in the gel-filtered platelets-plasminogen-t-PA mixtures was quantified. The same amountsof plasmin, while also inhibiting the disc-to-sphere transformation of the platelets, did not enhance thrombin-or U 46619-induced ATP secretion. When whole blood or platelet-rich plasma or gel-filtered platelets resuspended in α-antiplas-min-depleted plasma waspreincubated with t-PA, aggregation and/or shape change induced by ristocetin, arachidonic acid, the calcium ionophore A 23187, adenosine diphosphate, U 46619, thrombin, serotonin or platelet activating factor were not modified.Our results suggest that in a purified system the effects of t-PA plus plasminogen onplatelets are distinct from those of plasmin;it appears that low pharmacological concentrations of t-PA enhance the secretory responses to stimuli.
PLATELET FUNCTION IN PLASMA AT PHYSIOLOGICAL CALCIUM CONCENTRATION. THE USE OF VAC AS AN ANTICOAGULANT
Authors: Gool R Van , Reutelingsperger C P M , Hornstra G , Hemkera H C 
Published: August 2018

We have purified from human placenta an anticoagulatory protein (VAC, Mr= 32,000), which inhibits phospholipid dependent procoagulant reactions through a calcium dependent high affinity binding to procoagulant phospholipids..When tested in citrated platelet rich plasma (cPRP), VAC does not affect platelet aggregation and secretion in reponse to ADP, collagen and thrombin. Purified VAC (0.05 μM, final concentration; f.c.) was used as an anticoagulant to prepare PRP (VAC-PRP). Platelet aggregation (optical density method) and release of newly absorbed 14C-sero-tonin (5HT) in response to adenosine diphospate (ADP) were measured and compared with platelet responses incPRP obtained simultaneously fromthe same donor.The response of ADP stimulated platelets in VAC-PRP differs strikingly from that in cPRP. In the latter, platelets react with a dose-dependent primary aggregation, followed by a thrombin (Ila)-independent second wave of aggregation associated with 5HT-secre-tion.Platelets in VAC-PRP, however, demonstratean increased primary aggregation in responseto ADP, which is followed by a IIa-mediated second wave of aggregation and 5HT-secretion.Increasing the VAC concentration does not affect the primary aggregation response, but delayed the IIa-dependent secondary events in a dose-dependent way. At 0.5 μ M VAC, platelets react to ADP (10 μM f.c.) with reversible aggregation only. No matter this high ADP-dose, secretion reaction does not occur. At this VAC concentration, epinephrine (5 μM f.c.) does not cause aggregation and 5HT-release at all, whereas incPRP both reactions occur quite readily. Although in VAC-PRP, epinephrine retains its synergistic effect on ADP to aggregate platelets, no 5HT release was ever observed and the resulting aggregation was alwaysreversible It is concluded that VAC is a suitable anticoagulant to investigate platelet function in the presence of physiological calcium concentration. Since platelet aggregation and release appear very different from results obtained in the usual way (cPRP, low calcium concentration) the physiological meaning of this latter method needs re-evaluation. Finally, our results cast severe doubt on epinephrine as an important platelet stimulant under physiological conditions.
HEPARIN CATALYZED FACTOR XIa INHIBITION BY ANTITHROMBIN III
Authors: soons H , Jansen-claessen T , Tans G C , Hemker H C 
Published: August 2018

The inactivation of human factor XIa by human antithrombin III (AT III) was studied under pseudo-first order reaction conditions (excess AT III) both in the absence and presence of heparin. The time course of inhibition was followed using SDS-PAGE. After electrophoresis proteins were blotted onto nitrocellulose and stained either for glycoprotein or for AT III using antibodies against AT III. Concomittant with factor XIa inactivation two new slower migrating bands became visible on the blots. One of these, representing the intermediate complex consisting of one AT III complexed with one of the active sites present in factor XIa, appeared as a transient band. Complete inactivation resulted in a single band representing the complex of factor XIa with two AT III molecules. This indicates that inhibition of factor XIa by AT III can be described as:Quantitative analysis of the time course of inactivation was accomplished by measurement of the disappearance of factor XIa amidolytic activity towards the chromogenic substrate S2366. Pseudo first order reaction kinetics were observed throughout. The time course of inactivation and the distribution of the reaction products observed upon gelelectrophoresis are best explained assuming a mechanism of inactivation in which the two active sites present in factor XIa are inhibited in random order (i.e. independent of each other) with the same rate constant of inhibition (k1= k2)- The rate constant of inactivation for the active sites in factor XIa was found to be 1,000 M-1 s-1 in the absence of heparin and 34,900 M-1 s-1 in the presence of saturating amounts of heparin.- From the kinetic data a binding constant Kd of 0.11 uM was inferred for the binding of AT III to heparin. Experiments with four well characterized heparin fractions indicate, that the actual magnitude of the rate enhancement of factor XIa inactivation is, however, not only due to the binding of AT III to heparin, but also depends on the type of heparin to which the AT III is bound.