bluuebunny/crossref_metadata_2025 huggingface dataset:
STUDIES ON THE INTERACTIONS BETWEEN THE HEPARIN-LIKE SUBSTANCES AND HUMAN PLATELETS USING THE MONOCLONAL ANTIBODIES TO PLATELET GLYCOPROTEINS
Authors: Ruan C , Wan H , Zhang W
Published: August 2018

We reported the new sulphated polysaccharides, SJAMP and HLAMP that have been isolated from the sea cucumbers and compared their biological effects with those of standard heparin. (Med. J. Australia, 1986; 144: HS 17-21). SJAMP and HLAMP have an action that is independent of the antithrombin III and do not inhibit factor Xa, although they have potent antithrombin effect. SJAMP has been used as an antithrombin agent. As does heparin, SJAMP and HLAMP cause platelet aggregation of platelet-rich plasma. At the final concentration of SJAMP or HLAMP of 25μg/ml, a single wave of aggregation was observed.A second wave of aggregation can be induced at a concentration of SJAMP or HLAMP of 50μg/ml. In washed platelets, the platelet aggregation that was induced by SJAMP or HLAMP was fibrinogen-dependent. Furthermore ,plate let aggregation and the secretion of serotonin that is induced by ADP or arachidonic acid were enhanced by the prior addition of SJAMP or HLAMP.This effect may explain the cases of thrombocytopenia that may be observed in patients who are undergoing treatment with SJAMP. Using the monoclonal antibodies ( MoAb ) to human platelet glycoproteins (GP), we studied the SJAMP-p late let and heparin-platelet interactions. SZ-21 is a MoAb directed against GPIIIa and the epitope for SZ-21 is essential for the binding sites of fibrinogen on GPIIb/lIIa complex.SZ-2 is a MoAb to GPIb and recognize an epitope located on the peptide tail (Mr=35K) of the α-chain of GPIb. The platelet aggregation and the secretion of serotonin induced by SJAMP were inhibited by SZ-21, but not by SZ-2. However the preincubation of platelets with SJAMP at the final concentration of 25μg/ml or with heparin at 5μ/ml prevented the binding of radioiodinated-SZ-2 to human platelets. But SJAMP or heparin did not compete for the binding of radioiodinated-SZ-21 to human platelets. These results suggest that the platelet aggregation induced by SJAMP is dependent of the binding sites of fibrinogen on GPIIb/IIIa complex, and that the binding sites of SJAMP and heparin on human platelets are related with GPIb, but not with GPIIb/IIIa.
PLASMA-ARTIFICIAL SURFACE INTERACTIONS; ROLE OF CONTACT AND FIBRINOLYTIC SYSTEMS
Authors: Scott Cheryl F , Brash John L , ten Hove Pauline , Wojciechowaki Peter , Colman Robert W
Published: August 2018

The transient adsorption of fibrinogen (Fg) to artificial surfaces (Vroman Effect) is modulated principally by the procofactor, high molecular weight kininogen (HK). We investigated which form of HK was responsible for Fg displacement and also whether other proteins participated in the Vroman Effect. Experiments were performed at 23°C with a 5 min surface exposure to various concentrations of either normal plasma or plasma deficient in specific proteins to which 125I Fg had been added. Typically, Fg adsorption reached a maximum at 1% plasma and decreased at higher plasma concentrations. On all surfaces tested, Fg displacement was greatly reduced in HK-deficient plasma. Normal plasma,when exposed to the contact system activator, dextran sulfate, prior to its interaction with glass, displayed Fg displacement similar to untreated HK-deficient plasma.However, if Factor Xl-deficient plasma was incubated with dextran sulfate prior to exposure to glass, the Fg displacement pattern resembled normal, untreated plasma. These results suggest that the inactive cofactor form of HK (HMWKi) generated by Factor XIa (formed during extensive contact activation) does not displace Fg. Furthermore, Fg displacement was also reduced in untreated Factor Xll-deficient plasma exposed to glass, suggesting that the active cofactor form of HK (HMWKa) generated by exposure to kallikrein (during Factor Xll-dependent contact activation) may be the active participant in the Vroman Effect. The cofactor function of HK and its ability to displace Fg, therefore, appear to parallel. We also found that plasminogen or plasminogen activators were minimally involved in the Vroman Effect. Fg adsorption to glass in plasminogen-depleted HK-deficent plasma resembled Fg adsorption in a single protein system since more Fg was adsorbed and desorption failed to occur. A synergism may therefore exist between plasminogen and HK in the Vroman Effect. A better understanding of the mechanism of blood-artificial surface interaction is essential for the design of less thrombogenic biomaterials.
THROMBOPHILIA:ITS CAUSES AND A ROUGH ESTIMATE OF ITS PREVALENCE
Authors: Briët E , Engesser L , Brommer E J P , Broekmans A W , Bertina R M
Published: August 2018

Idiopathic venous thrombosis and embolism have gained widespread interest since the discovery that, deficiencies of antithrombin III, protein C, and protein S are associated with familial venous thrombophilia. The purpose of our study was to obtain an estimate of the prevalence of this syndrome and to establish the etiology in as many cases as possible.

We collaborated with specialists from 37 Dutch hospitals, covering about 10% of the Dutch population. A history as well as blood samples were obtained from 113 unrelated cases with familial thrombophilia and from 90 isolated cases. Assuming that each proband in a family with thrombophilia has an average of four affected relatives, a rough estimate of the prevalence of familial thrombophilia in The Netherlands is 40 cases per 100.000. The prevalence of non-familial thrombophilia is probably lower.

In 35 out of the 113 familial cases we established a diagnosis of hereditary antithrombin III deficiency (n=5), protein C deficiency (type I: n=9; type II: n=4), protein S deficiency (n=15) and dysfibrinogenemia (n=2). In 36 cases we found no abnormality at all and in the remaining 42 cases abnormalities were found in one or more of the following: heparin cofactor II, factor V, factor VII, factor VIII, von Willebrand factor, plasminogen, tissue plasminogen activator, plasminogen activator inhibitor, alpha 2 antiplasmin and histidine rich glycoprotein. In most of these cases, however, the hereditary nature of the abnormalities could not be demonstrated and the causal relationships remain to be established.

In the 90 isolated cases, we diagnosed hereditary deficiencies of anti thrombin III, protein C and protein S each in one case and a lupus anticoagulant in two cases. In 54 cases no abnormality was found and in the remaining 31 cases various abnormalities were found in one or more of the proteins mentioned above.

We conclude that the syndrome of thrombophilia is not rare but its true prevalence needs to be established by more rigorous means. An etiological diagnosis can be made with confidence in only one third of the familial cases and in less than 10 percent of the isolated cases.
EARLY RESULTS OF A RANDOMIZED, DOUBLE-BLIND DOSE-RANGING STUDY OF I.V. STREPTOKINASE FOR ACUTE MYOCARDIAL INFARCTION
Authors: Six A J , Louwerenburg J W , Braams R , Mosterd W L , Bredero A C , Kerkkamp H J , Brommer E J P , van Hemel N M
Published: August 2018

101 patients suffering from acute myocardial infarction during less than 4 hours were immediately treated with intravenous (i.v.) streptokinase (SK), infused in 1 hour. No concomitant medications like steroids, salicylates or anti-arrhythmic drugs were routinely given.

Patients were blindly allocated to one of four dosages of SK (see below). Coronary angiography was performed within 3 hours after SK infusion in 90% of all patients . The infarct-related vessel was open in 59% of 91 patients. The results in the four dosage groups were as follows:

Haematomas at the puncture site were common complications in all groups. No strokes occurred, nor life-threatening bleeding complications. Blood transfusion was needed in only one parient, who had an important bleeding and formation of a large haematoma at the puncture site.

It is concluded that there is a trend to better results of higher doses of i.v. SK in patients suffering from acute myocardial infarction without an evident rise of the rate of complications. The efficacy and safety of recently developed fibrinolytic drugs and streptokinase should be compared at optimal dosages.
THE DEACYLATION OF P-ANISOYL PLASMINOGEN-STREPTOKINASE ACTIVATOR COMPLEX (APSAC, EMINASE™)
Authors: Ferres H , Hibbs M J , Smith R A G
Published: August 2018

The deacylation of the thrombolytic acyl-enzyme APSAC (BRL 26921) has been studied in various media using a radiochemical method. In a buffer containing glycerol, the half-life for deacylation at pH 7.4, 37°C vi/as c. 20-50 min. depending on the concentration of APSAC. The concentration-dependence u/as found to be linked to the availability of free enzyme active centres during the deacylation process and could be normalised to about 50 min. by addition of inhibitors of plasmin or streptokinase, plasmin. In glycerol-free buffer, the deacylation half-life was 147 ± 5 min., indicating that glycerol, which is required to stabilise SK.Pm in activity-based assays caused artefactual acceleration of deacylation. In human plasma, the deacylation half-life was 104 ± 6 min. and was not concentration-dependent. In clotted human plasma, under conditions where APSAC was fibrin-bound, the deacylation half-life was 128 ± 10 min. which suggested that the deacylation process was not significantly influenced by binding of molecule to fibrin. The deacylation rate of APSAC in human plasma was similar to the plasma clearance rate at therapeutic doses in man (Been, M. et al., Int. J. Cardiol. 11 (1980) 53-61)
FIVE-YEAR-FOLLOW-UP OF PATIENTS WITH UNSTABLE ANGINA: SURGICAL VERSUS MEDICAL TREATMENT
Authors: Nellessen U , Jost S , Hecker H , Specht S , Danciu V , Lichtlen P R
Published: August 2018

Among patients (pts) with coronary artery disease those with symptoms of an unstable angina pectoris form a subset particularly jeopardized with regard to threatening myocardial infarction (MI) or cardiac death (CD). We analyzed over 5.4±2.1 years (Y) the clinical course of 123 pts, who between 1977 and 1982 had to be admitted to the intensive care unit for reasons of persisting angina at rest. Within the first 24 hours no patient revealed a significant elevation of serum creatine kinase or typical alterations in the ECG due to acute MI (new Q-waves). During their stay in hospital (19±17 days) 43 pts (37 men, 6 women; age 58±7 Y) were subjected to bypass graft surgery, 80 pts (60 men, 20 women; age 58jh10 Y) were medically treated, 13 of whom underwent subsequent bypass graft surgery because of aggravation of symptoms. The table presents a survey of cardiac mortality and incidence of MI in the collectives with medical and surgical treatment during the stay in hospital and 1, 3 and 5 Y after dismissal (calculated according to the life-table method of Kaplan-Meier).

Hence, during the initial hospitalization infarction and mortality rate in the medically treated group indeed were smaller than in the surgical collective; however, after dismissal this beneficial mortality rate turned into the opposite in the course of the following years. In this group nearly every MI was fatal.
PLATELET REACTIVITY AND FIBRINOGEN LEVELS IN UNSTABLE CORONARY ARTERY DISEASE(UCAD)
Authors: Swahn E , von Schenck H , Wallentin L
Published: August 2018

Unstable angina and non-Q-wave myocardial infarction represents the unstable phase Of coronary artery disease (CAD). In UCAD a thrombosis in a coronary artery could be the triggering factor of the unstable phase. Increased platelet reactivity and hypercoagulability could be the predisposing factor for developing this condition. Therefore, in patients with UCAD the platelet reactivity was measured as the aggregation response to ADP and collagen, the platelet sensitivity to PgI2 and the release of platelet derived proteins. As an indicator of hypercoagulability the fibrinogen level in plasma was analysed. The control group consisted of patients with chest pain but without CAD. Blood samples for platelet tests and fibrinogen analysis were obtained in the acute phase and after one year.

Results.: The only difference in platelet reactivity between cases and controls was noted in their sensitivity to PgI2. The difference remained in the females but not in the male UCAD group after one year.

In the acute phase a diagnosis of UCAD, elevated weight index and smoking contributed independently to increased fibrinogen levels.

Conclusion: The increased fibrinogen level and decreased platelet sensitivity to PgI2 might reflect a hypercoagulable state in patients with UCAD.
ANALYSIS OF HYPERCOAGULABILITY BY AUTOMATED FLUOROGENIC METHODS
Authors: Kato H , Uchida K , Okada Y , Yamaguchi T
Published: August 2018

In order to detect hypercoagulable state due to the increase or decrease of coagulation factors and inhibitors concentrations or the presence of active coagulation factors or tissue factor in plasma, highly sensitive automated methods were developed using fluorogenic substrate for thrombin. Coagulability of human plasma was measured by mixing 3 yl of plasma with Thromborel S (TF), calcium and Boc-Val-Pro-Arg-MCA(MCA) (Fluorogenic PT, FPT). FPT of normal plasma was shortened by the addition of purified X or VII (Final conc. 1-5 U per ml), and of thrombin (0.3-1 ng) or Xa (10500 pg). Factors VII and X contents in plasma were measured by mixing 3 yl of diluted plasma with each factor deficient plasma, TF, calcium and MCA in which 10 %-800 % of each factor was quantitatively measured. TF and Xa were measured by mixing with XII or X deficient plasma, phospholipid, calcium and MCA. By this method, 5-500 pg of Xa or 1-1000 units of TF (assuming that one vial of Thromborel S contains 2,000,000 U TF per ml) was quantitatively measured. All the experiments were performed using a centrifugal autoanalyzer (Cobas Bio) with FIA module. The reaction time to reach 0.1 relative fluorescence was calculated by a computer using a program developed by us.

These automated methods were applied to examine the hypercoagulability of plasmas from patients with cerebral infarction. Sixty five samples out of 75 showed shorter FPT than control plasma. Xa was detected with the conc. of 3-13 ng Xa per ml. FPT of patient plasmas correlated with Xa content (r=0.70) and X (r=0.63). Xa activity of patient plasma was eluted in the same peak as purified X on gel-filtration of Sephacryl S-200 column and completely inhibited by anti X rabbit IgG. Xa activity was also found in normal serum. The conventional PT or chromogenic PT methods are sensitive to hypocoagulable state but not to hypercoagulab le state. The present automated methods were proved to be sensitive to hypercoagulable state and demonstrated that the presence of Xa or the increase of X concentration in plasma contributes in part to the hypercoagulable state of cerebral infarction.
FIRST EXPERIENCE WITH A NEW SYSTEM TO MEASURE PRIMARY HEMOSTASIS IN VITRO
Authors: Zekert F , Hufnagl A , Hufnagl A , Kratzer M A A
Published: August 2018

Control of hemostatic parameters of patients undergoing surgery usually involves only determination of parameters of the coagulation cascade, but not measurement of primary hemostasis. This has mainly methodological reasons. Recently a model of primary hemostasis has been introduced (Kratzer & Bom, Haemostasis 15:357; 1985) now produced under the name “ Thrombostat 4000” (VDG von der Goltz, 8221 Seeon, West Germany). This device measures computerized within minutes “ in vitro” bleeding parameters (vBP) like bleeding volume (V,ul), time (T,sec) and the viscosity depending initial flow (IF,ul/min) in a small sample (0.5-lml) of whole anticoagulated blood (Na citrate 1 to 10). The clinical relevance of the vBP was tested in patients undergoing major surgery.

Results : Case 1: A 78 years old woman with osteomyelosarcoma, heavy bleeding and normal coagulation parametrs showed strongly pathological vBP: (V > 800, T > 300, IF 184); control values: (V = 177, T = 105, IF = 145); An improvement of beeding and shortening of vBP was observed after infusion of platelet concentrate: (V = 328, T = 245, IF = 147).

Case 2: A 60 years old man with adenocarcinoma undergoing liver transplantation, before operation (OP) vBP: (V = 224, T = 114, IF = 182); displayed a strong increase during OP: (V > 800, T = 360, IF = 277; decreasing values after Oft (V = 348, T = 146, IF = 254); 1. day after OP: (V = 250, T = 127, IF = 221); 13 day after OP normal vBft (V = 160, T = 111, IF 182).

Case 3: A 35 years old man with III. grade burnings of the skin (35%) and a massive platelet function defect: (V > 800, T > 180, IF = 328); improvement after infusion of platelet concentrate: (V = 393, T = 164, IF = 239); further improvement some hours later: (V = 240, T = 120, IF = 213); and normalizing of parameters at the 1. day: (V = 197, T = 126, IF = 186) and the 5. day after OP: (V = 130, T = 122, IF = 142).

It is interesting to note that patients with heavy burnings reguarly displayed reduced vBP: (V = 120, T = 70, IF = 127) if measured very early after the accident. The new method seems to be a valuable instrument to judge platelet functions.
IS D. DIMERS DOSAGE USEFUL FOR DIAGNOSIS OF PRETHROMBOTIC STATE DURING POST-OPERATIVE PERIOD ?
Authors: Le Querrec A , Derlon A , Thomas M
Published: August 2018

62 patients were at random blindly given either Kabi 2165 or commercial heparin for 6 days in prophylaxis of post-operative DVT after abdominal surgery. The radiofibrinogen uptake test (FRUT) was performed every two days during 6 days. D. Dimers quantification was performed with an enzyme—linked immunosorbent assay using monoclonal antibodies : ELISA (Diagnostics Stago). D. Dimers quantification allowed us to share out patients amongst two groups :

1) Mild abdominal surgery,

2) Oncologic surgery.

In both groups, no difference was observed according to the treatment (p> 0.5) We saw a significant rise of D. Dimers from D-l to D6 (p< 10-6) in both groups, with significantly upper values in group 2 (p< 0.01).

Among 62 patients, 3 had positive RFUT. There was no significant difference between D. Dimers values of these 3 patients and D. Dimers values of the 59 patients with negative RFUT.

Thus, the rise of D. Dimers during post—operative period was not associated with DVT in these 59 patients.
PLASMINOGEN ACTIVATOR ACTIVITY OF NORMAL AND MALIGNANT MONONUCLEAR HUMAN CELLS
Authors: Filippi J F , Arnoux D , Tubiana N , Boutière B , Le Caär F , Sampol J , Hématol Lab , Sampol Pr J , Carcassonne Pr Y
Published: August 2018

Plasminogen activators (PA) are thought to play a role in the invasive and metastatic properties of many types of cancer cells. Though, discrepancies in correlations between fibrinolytic activity and metastatic potential of malignant cells have been described.

In this study, we evaluated both tissue type (tPA) and urokinase type (UK) cellular PA activities in different mononuclear cell types : normal T and B human peripheral lymphocytes, B cells from patients with chronic lymphocytic leukemia (CLL), human blood monocytes, alveolar macrophages, U 937, RAJI and JM cell 1ines.

Mononuclear cells were isolated by Ficoll-hypaque gradients and monocytes by plastic adhesion. T and B cells were separated by a rosetting technique using sheep red blood cells. Cellular extracts were prepared by 0.5 % Triton X 100 buffer treatment followed by sonication and centrifugation 10 ' at 2000 g. PA assays were performed on the supernatants.

UK-type PA was evaluated by a liquid-phase assay in presence of human plasminogen (Kabi) and chromogenic substrate S 2251 (Kabi).

tPA was determinated using a solid-phase fibrin activity assay which involves an affinity separation step and thus allows selective detection of tPA.

In both cases, results were reported in international units by reference to standard curves of UK (Choay) or tPA (Kabi).

In all cell types tested, PA detected was essentially urokinase-type. Highest PA activity was found in U 937 cells (0.7 IU/5×l06 cells). In normal blood lymphocytes, mean PA activity was 0.08 IU/5×l06 cells. Examination of lymphocytes from patients with CLL revealed a marked decrease in UK activity as compared to normals (< 0.01 IU/5×106 cells in more than 50 % cases).

The function of PA in normal lymphocyte physiology and the potential pathogenic role of diminished PA in CLL lymphocytes remains to be investigated.
INHIBITION OF ENDOTHELIAL CELL PROLIFERATION BY NORMAL HUMAN MONOCYTES
Authors: Liote F , Wautier M P , Savariau E , Setiadi H , Wautier J L
Published: August 2018

Human peripheral blood monocytes and macrophages possess factors which are capable of inhibiting or stimulating endothelial cell proliferation. We have further explored if such activity is due to cytotoxic effects of monocytes. Normal mononuclear cells were isolated first by density gradient. Monocytes were then purified by three different techniques: 1) counter centrifugation elutriation (CCE) (Beckman) 2) selective adhesion to gelatin-plasma (GPI) 3) selective adhesion to fibronectin (Fn). Cytotoxicity was estimated by counting the release of 51cr used to label the human umbilical vein endothelial cells (HUVE) prior to the addition of monocytes. Whilst [3H] thymidine incorporation by HUVE permitted us to measure the effect of monocytes on the growth of the endothelial cells. Monocytes were incubated with HUVE (12×103) for 24 to 36h at various concentrations '(1.5-12×103). No cytotoxic effect could be demonstrated but an inhibition of [3h] thymidine uptake was observed and was dependent upon monocytes concentration. Monocytes isolated on GP1 exhibited a significantly higher inhibitory effect (p<0.05) compared to those purified on Fn or by CCE.(GP1: 85±6%, Fn:58±6%, CCE:67±5%). These results indicated t*hat normal monocytes can inhibit endothelial cell proliferation. This activity appeared to be higher when monocytes were isolated on GP1 which suggest that the adhesion on this surface could stimulate monocytes not only by its fibronectin receptor. This inhibitory activity of monocyte on endothelial cells proliferation could be different in patients with vascular disorders.
TUMOR-ASSOCIATED FIBRINOLYSIS IN OVARIAN CARCINOMA - HPLC AND N-TERMINAL AMINO ACID ANALYSIS REVEAL THE PATHWAY OF DEGRADATION OF CROSSLINKED FIBRIN
Authors: Wilhelm O , Henschen A , Hafter R , Graeff H
Published: August 2018

Crosslinked fibrin has been demonstrated by immunohistochemi-cal tests to occur around tumor plugs, on the surface and in the stroma of the tumor in ovarian cancer. High levels of D-Dimer (200-800μg/ml), the characteristic terminal degradation product of crosslinked fibrin, are found in ascitic fluid of patients with advanced ovarian cancer. These findings suggest that fibrin polymerisation and degradation are related to and even may influence tumor growth. The kind of proteases which are responsible for degradation of crosslinked fibrin is, however, unknown.lt was the aim of this study to evaluate whether plasmin and/or other proteases are involved in tumor-associated fibrinolysis. Therefore the total high-molecular-weight fibrin degradation products in ascitic fluid were purified by protamine sulfate precipitation, gel filtration, immunoadsorption and compared with the components of plasmin-degraded crosslinked fibrin, i.e. DD,DY,YX,DXD and DXY, by direct SDS-PAGE in the absence of mercaptoethanol and after excision of the bands, mercaptolysis and re-electrophoresis. Pronounced similarity between the two sets of fragments was observed. For further information the fragments from the two sources were mercaptolysed and their polypeptide chain components separated by reversed-phase high-performance liquid chromatography, the components being identified by N-terminal sequence analysis and SDS-PAGE. Highly similar patterns were obtained and components corresponding to γ-γ ,γ-γ1, β, β2 and α1 could be recognized. The findings provide strong evidence for plasmin being the primary protease involved in ovarian carcinoma-related fibrinolysis, (supported by Deutsche Forschungsgemeinschaft.SFB 207, A2).
PHARMACOKINETICS OF EN0XAPARIN AFTER SINGLE SUBCUTANEOUS ADMINISTRATION OF INCREASING DOSES (20 UP TO 80 MG) TO HEALTHY VOLUNTEERS
Authors: Bara L , Le Roux Y , Woler M , Chauliac F , Frydman A , Samama M
Published: August 2018

The pharmacokinetics of enoxaparin (E) was randomly studied in 12 healthy male volunteers. Each dose (20-40-60 and 80 mg) was injected via subcutaneous (sc) route with a one-week wash out period. Anti-Xa and anti-IIa activities (ACT), calcium thrombin time (CTT) and Heptest were measured over a 36 hour period. E and the IV th International Heparin Standard were both used as internal standards.

The anti IIa and CTT effects were only measurable when the injected dose was higher than 40 mg. The maximum anti-Xa and anti-IIa ACT were obtained 3 to 4 hours after the dose. As anti-IIa ACT is lower than anti-Xa ACT (anti-Xa/anti-IIa ACT ration I .6 to 2), the complete pharmacokinetic description of E was only based on anti-Xa data. Thus, the mean values of the maximal anti-Xa ACT (A max) were respectively: 1.58 ± 0.35 pg/ml; 3.83 ± 0.98 jig/ml, 5.38 ± 0.75 ug/ml and 7.44 ± 1.4 pg/ml for the four doses (20-40-60 and 80 mg). The resorption of E after sc injection was strictly linear whereas the relationships between A max or AUC in the one hand and dose in the other hand were A (anti Xa) Max = 0.0954 (dose) - 0,2083 r = 0.9146/p < 0.001; n = 48) and AUC (0 - 36 h) = 0.9117 (dose) - 7.59 (r = 0.9133/p < 0.001; n = 48). The mean residence time of E was close to 6 h (5.83 ± 0.86 h for D = 40 mg; 6.19 ± 0.74 h for D = 60 mg and 6.44 ± 0.76 h for 80 mg) indicating that around 50% of the total anti Xa ACT is induced in a 6 hour interval. The apparent volume of distribution V is close to 61 (6.59 1 ±1.33 1 for D = 60 mg) and the total Dody clearance is equal to 1.25 1/h, indicating the rate of depolymerisation of enoxaparin is lower than that of heparin. Plasma elimination half-life of anti-Xa ACT is equal to 4.36 ± 1.07 h (D = 40 mg) whereas that of anti-IIa ACT is shorter, fi) = 2.1 h). These results indicate that enoxaparin exhibits i) a differential anti-Xa/anti-IIa ACT profile, ii) a linear relationship between dose and anti-Xa/anti-IIa ACT and iii) a kinetic profile which is significantly different from that of standard heparin.
TOLERANCE OF CY 216 AS THROMBO-EMBOLIC DISEASE PREVENTION : EVALUATION OF LOCAL HAEMORRHAGIC RISK IN OPHTAL SURGERY - Preliminary results
Authors: Morin Y , Limon S
Published: August 2018

The specific biological activity of low-molecular weight heparin prompted using CY 216 in ophtalmological surgery for thrombo-embolic prevention. We report preliminary results on 31 patients (9 males, 22 females, mean age 74,4) treated from 06/86 to 12/86 with a daily 0,3 ml sub-cutaneous injection of CY 216 started 2 hours prior to surgery until day 7, or day 10 for 7 patients. Coagulation tests included TCa and anti-Xa activity. All patients were checked daily for ocular haemorrnagies and thrombo-embolic manifestations. Anaesthesia was general in 16 cases and local in 15. Surgery was performed on 21 cataracts (67 %), 8 retinal detachments (26 %), 2 glaucomas (6 %).

No patient developped any clinical thrombo-embolism condition. In that particular surgery where frequent local haemorrhagic complications occur and delay the onset of heparinotherapy, CY 216 treatment exhibited 3 minor eyelids ecchymosis, 1 choroid hematoma and 5 subconjonctival suffusions, all transient and not impacting specific surgical results ; and all already known as possible mechanical vascular aggression independant of heparinotherapy. 2 hyphemas (6 %) also occured, for which CY 216 was discontinued, still not impacting surgical results, and without excessive hypocoagulation according to tests. These biological tests showed no adverse effects ; TCa never raised more than 6" above controls, and anti-Xa activity raised to 4 times pre-treatment values ; in 3 patients, high values did not induce any haemorrhagic complications, a very strong argument in favor of excellent tolerance of CY 216 therapy.

At this stage of preliminary results, the tolerance of CY 216 concerning local haemorrhagic risk in eye surgery can be evaluated as near to excellent.
THE PHARMACOKINETICS OF 125-I DERMATAN SULFATE IN THE RABBIT
Authors: Dol F , Houin G , Dupouy D , Caranobe C , Cadroy Y , Sié P , Boneu B
Published: August 2018

We have determined the main pharmacokinetic parameters of dermatan sulfate (DS), a catalyst of IIa-heparin cofactor II (HC II) interaction which presents antithrombotic properties in the rabbit. DS (Pharmuka, France) was conjugated with SHPP and iodinated using the chloramine T method. The labelled derivative had the same MW distribution and biological activities than.the native one. Rabbits were injected by 5 ucies of 125I-DS (0.6 ug) and increasing doses of unlabelled DS. Serial blood samples were collected to measure cpm disappearance and, in some cases, residual biological activity was determined (ex vivo quantitation of IIa- 125I-HC II complexes). The cpm curves were broken into 3 exponentials : alpha, beta and gamma. The beta exponential was closely superimposable to the curves of biological activity disappearance. The main pharmacokinetic parameters are indicated in the Table (mean ± SD) : there was a slight (non-significant) tendency to the half life (Tl/2) prolongation and to the reduction of both the clearance (cl) and the volume of distribution (Vd). Thus after IV injection, the pharmacokinetics of DS mimics that of LMW-heparin in the rabbit : Tl/2 is in the same order of magnitude and independent of the dose delivered. These results are promising for the future development of this compound as an antithrombotic agent.
PREVENTION OF CORONARY VEIN GRAFT OCCLUSION: LOW-DOSE ACETYLSALICYLIC ACID VERSUS COUMARIN (ASAAC - STUDY)
Authors: Weber M A J , Taillens C , Hasford J , Spannagel M , Schramm W , Hauf E ,   ASAAC - Study Group
Published: August 2018

Thrombotic graft occlusion occurs within a few hours after surgery, suggesting a benefit of preoperative start of antiplatelet treatment. We investigated the effectivity and risk of preoperatively started treatment with 100 mg/day acetyl salicylic acid (ASA) compared to anticoagu1 ation started 6 hours postoperatively (heparin followed by coumarin (AC)). The prospective randomized trial yielded the following results:

Preoperative low dose ASA increased chest-tube blood loss. This indicates effective antiplatelet activity of low dose ASA. Perioperative platelet consumption and coagulation factors activity was not altered.It is concluded, that graft patency rates are similar with postoperative anticoagu1 ation or antiplatelet treatment with low dose acetylsalicylic acid.
MODEL STUDIES OF NEUTRALIZATION OF THROMBIN
Authors: Reeve E B
Published: August 2018

A kinetic model, based on published studies of thrombin neutralization, is used to examine factors that limit spread of free thrombin in a simple plasma. It employs equations with presently available rate parameters which describe the courses of the major thrombin-binding reactions at 37°C in buffered saline solutions approximating plasma ultrafiltrate. Thrombin is bound reversibly by fibrinogen and fibrin-1 polymers as enzyme-substrate complexes (1) and by “fibrin” at a non-proteolyt ic site (2), and essentially irreversibly by antithrombins (3). These bindings reduce free thrombin levels and so limit spread of activity. The model equations with parameters from (1) and (3) show that thrombin neutralization by thrombin-substrate complexes is very brief and thrombin-antithrombin reactions are much too slow for early reduction of thrombin activity. However, parameters from (2) show that rapid reversible binding of thrombin by “fibrin” much reduces level of free thrombin and the level continues to fall as the thrombin is passed to the antithrombins. The model shows that a rapidly-acting antithrombin (e.g. heparin-ATIII) could reduce free thrombin fast enough to inhibit slower thrombin activations (e.g. of FXIII), and that a sufficient concentration of a reversible binder can govern the level of free thrombin. This suggests that a non-toxic reversible binder, with suitable Kd and half-life, would be valuable in treating thrombosis. Verification and extension of the model findings require better experimental definition of the parameters.

(1) Lewis, S.D. et al. J. Biol. Chem. 260, 10192-10199, 1985.

(2) Liu, C.Y. et al. J. Biol. Chem. 254, 10421-10425, 1979.

(3) Jordan, R. et al. J. Biol. Chem. 254, 2902-2913, 1979. (Supported by grants from the Colorado Heart Foundation)
SPECIFIC DETECTION OF FIBRIN IN HUMAN TISSUES BY A NEW IMMUNOHISTOCHEMICAL TECHNIQUE.
Authors: Bini A , Mesa-Tejada R , Fenoglio J , Kudryk B , Kaplan K L
Published: August 2018

Human biopsy (30), surgical (50) and autopsy (14) specimens of different embryonic origin (skin, blood vessel, kidney, lymph nodes, prostate, lung, liver, and intestine) were stained by the avidin-biotin complex immunoperoxidase technique (ABC-IP) with monoclonal antibodies (MAbs). MAb T2G1 (recognizes 315-42 and detects fibrin II in tissues), MAb I8C6 (recognizes BS1-42 and indicates fibrinogen and fibrin I), MAb GC4 (specific for fragments D and D-D), and a polyclonal antiserum for fibrinogen. The method can be applied to frozen or Boilin’s fixed paraffin embedded tissues with good preservation of morphology and high sensitivity at the light microscopy level. The results were compared with conventional histochemical stains currently used in surgical pathology to demonstrate fibrin deposits in tissues. These stains are based on the acidophilic properties of fibrin (Fraser-Lendrum for “more recent” and Mallory’s PTAH for “older” fibrin). ABC-IP staining with MAb T2G1 clearly detected fibrin in areas where Lendrum and PTAH failed to reveal fibrin deposits, e.g., in the intercellular and pericellular matrix, as well as in areas where staining occurred with conventional techniques, indicating greater sensitivity of the ABC-IP method. Fibrin was specifically detected in strands or clumps in some areas of inflammation and granulation tissue and seemed to be associated with platelets and macrophages. Moreover, ABC-IP with MAb I8C6 and MAb GC4 permits the distinction between fibrinogen or fibrin I, and D and D dimer which are poorly reactive with the Lendrum and PTAH methods. The polyclonal antiserum for fibrinogen showed reactivity with all the material stained with the MAbs and with some additional areas due to the epitopes of fibrinogen and fibrin not detected by the monoclonals. The ABC-IP technique with MAbs allows specific demonstration of fibrin deposits in tissues. Moreover, these results indicate that this method facilitates the correlation of the morphologic appearance of fibrinogen) -related deposits in tissues with their molecular form and will be useful to elucidate the role of fibrin in diseases such as atherosclerosis, kidney disease, and tumors.
FIBRINOGEN BIRMINGHAM; A NEW CONGENITAL HETERODIMERIC DYSFIBRINOGENEMIA WITH DEFECTIVE FIBRINOPEPTIDE A RELEASE (Aα 16 Arg→His)
Authors: Siebenlist K R , Prchal J T , Masesson M W
Published: August 2018

Aα 16 Arg→His substitutions are common forms of congenital dysfibrinogenemias. Clinical manifestations range from asymptomatic to moderate hemorrhagic tendencies. Biochemical characterization of one such heterozygotic individual (Fibrinogen Louisville, Galanakis, etal. Ann NY Acad Sci 408:644,1983) indicated that only homodimeric fibrinogen molecules (i.e., containing either normal or abnormal Aα chains) were present. We isolated fibrinogen from the plasma of a 23 year old patient with a history of easy bruising and several recent moderate to severe bleeding episodes. Coagulability with reptilase was 677 (65-70%; n=5) whereas with thrombin (Ha) it approached 100%, depending directly upon the time of incubation with enzyme. HPLC analysis of Ila-induced fibrinopeptide release demonstrated the presence of an abnormal A-peptide (A*), amounting to 50% of the total, which was released more slowly than the normal A-peptide (A). Amino acid analysis of A* demonstrated the absence of Arg and the presence of His. Carboxypeptidase digestion confirmed the structure of A* as Aα 16 Arg-→ His. The clot and the soluble clot liquor resulting from reptilase treatment were separated and each was then further treated with Ilato release A*. HPLC analysis indicated that 31% of the total A* present in the sample was associated with the reptilase clot and 697 remained in the clot liquor. This distribution of A* suggests that Fibrinogen Birmingham, unlike Fibrinogen Louisville, contains heterodimeric molecules that are incorporated into the reptilase clottable fraction. This finding is consistent with a process of random hepatic assembly of dimeric fibrinogen molecules in a heterozygotic individual.
FIBRINOPEPTIDE B RELEASE FROM NORMAL FIBRINOGEN AND FIBRINOGEN LONDON I IN THE PRESENCE OF INHIBITORS OF FIBRIN POLYMERIZATION
Authors: Ruf W , Bender A , Preissner K T , Lane D A , Müller-Berghaus G
Published: August 2018

The fibrinopeptides A and B (FPA and FPB) are cleaved from the fibrinogen molecule with different rates. In the initial phase of the thrombin-fibrinogen reaction, FPB is released with a slow rate, which is enhanced upon polymerization of desA-fi-brin monomers. The aim of the present study was to further characterize the mechanism leading to the enhanced rate of FPB release during polymerization. For this purpose, the release of FPB from normal fibrinogen and from fibrinogen London I, which exhibits a polymerization defect located in the D-domain, was studied in the presence and absence of the fibrinolytic fragment D1 (D1) and of the synthetic tetrapeptide Gly-Pro-Arg-Pro (GPRP). Steady state parameters for fibrinopeptide release were determined under pseudo-first order reaction conditions. In the initial phase of the thrombin-fibrinogen reaction, the release of FPA was unchanged in the presence of D1. Furthermore, the release of FPA from fibrinogen London I did not reveal any difference in comparison to normal fibrinogen. GPRP prevented not only fibrin polymerization, but also the enhanced rate of FPB release. On the contrary, the rate of FPB release in the presence of a 16- and 32-fold molar excess of over fibrinogen did not differ from a reaction mixture with no added D1. Si-miliar to the inhibited rate of FPB release in the presence of GPRP, the release of FPB from fibrinogen London I occurred with a slow rate, which was not enhanced by the addition of a 16-fold molar excess of D1. Since the release neither from normal fibrinogen nor from ribrinogen London I was affected by D1, it was concluded that the D-E contact formed by D1 with an E-domain of a desA-fibrin molecule does not enhance the release of FPB. While GPRP keeps fibrin in monomeric form by inhibiting the polymerization sites in the D-domains, D1 does not prevent the formation of fibrin oligomers. Therefore, acceleration of FPB release is caused by a conformational change, which is induced by binding of reciprocal polymerization sites to an E-as well as a D-domain of the same desA-fibrin molecule.
VASOCONSTRICTOR EFFECTS OF AGGREGATING PLATELETS IN RABBIT PULMONARY ARTERIES WITH AND WITHOUT ENDOTHELIUM
Authors: Janssens W J , Van Nueten J M
Published: August 2018

The aim of the present experiments was to investigate the modulatory role of the endothelium on vasoconstrictions induced by aggregating platelets. Rings of rabbit pulmonary arteries were mounted for isometric tension recording. The presence or absence of the endothelium was confirmed using acetylcholine-induced relaxations. All contractions were expressed as percentage of a K+-induced (100 mM) contraction. Thrombin was administered to the preparations at 0.5 NIH units/ml. At this concentration the enzyme caused no or only very small contractions, but apparently induced maximal platelet activation in this experimental setting. Cumulative administration of rat platelets in the presence of thrombin caused contractions of the arteries. These contractions occurred at lower platelet amounts and were larger in endothelium-deprived rings than in preparations with intact endothelium. This indicates that mediators released from aggregating platelets cause contraction of the vascular smooth muscle cells which are attenuated by (a) factor(s) released from the endothelium. Platelet-induced contractions were dose-dependently inhibited and finally abolished by the S2-serotonergic antagonist ketanserin and inhibited to a lesser extent by the thromboxane A2 antagonist BM-13177. This indicates that serotonin, and to a lesser extent thromboxane A2, are the mediators of platelet-induced contractions and that mutual amplification of their vasoconstrictor effect may occur. Serotonin-induced contractions of pulmonary artery rings occurred at lower concentrations and were larger in endothelium-deprived preparations indicating that the endothelium derived factor(s) attenuating platelet-induced contraction may be released upon stimulation of the endothelium by serotonin. The pA2-value of ketanserin against serotonin-induced contractions was similar in endothelium-deprived preparations and preparations with intact endothelium. This indicates that the stimulating effect of serotonin on the endothelium is not mediated by the S2-serotonergic mechanism responsible for vascular smooth muscle contractions.
EFFECT OF LIPID PEROXIDES ON PROSTACYCLIN AND THROMBOXANE GENERATION IN HYPERCHOLESTEROLEMIC RABBITS
Authors: Jian Wang , Yungcai Lu , Erzhen Zhen , Zhaozheng Guo , Fang Shi
Published: August 2018

Rabbits feeding on atherogenic diet for 60 days resulted in high level of plasma lipid peroxides as well as extreme hypercholesterolemia. Both of them kept at high level until 35 days after atherogenic diet stopped. At the same time, as compared with the control group, plasma PGI2 level was remarkably decreased while TXA2 and platelet aggregability were increased. Atherosclerotic vessel walls contain high levels of lipid peroxides associated with decreased PGI2 and increased TXA2 generation. Atherosclerotic plaques had the highest level of lipid peroxides and TXA2 while PGI production was the least, as compared with non-plaque tissue of the same artery and the normal arteries. The condition of normal arteries was just reverse. It was concluded that the concurrent presence of lipid peroxidation products may be seriously considered when evaluating the hyperlipidemia as a cause of atherosclerosis, and the elevation of TXA2 generation in arteries might be taken into consideration when evaluating an imbalance of PGI2/TXA2 in plasma.
EFFECT OF NICOTINE ON HUMAN UMBILICAL VEIN ENDOTHELIAL CELLS IN CULTURE : PROSTACYCLIN PRODUCTION AND PROLIFERATION STUDIES
Authors: BOUTHERIN-FALSON O , BLAES N
Published: August 2018

Clinical observations and results from animal studies indicate that nicotine may play a role in vascular disorders related to smoking. It has been reported that nicotine could alter vascular prostacyclin (PGI2) production and increase the number of circulating endothelial cells. In the present study, the direct effect of nicotine on endothelial cells in culture was investigated : Both PGI2 production and proliferative abilities were studied.

PGI2 production studies : human umbilical vein endothelial cells (HUVEC) were grown in 4 days to confluency in control medium (RPM/199 1:1 + 20% fetal calf serum). At the beginning of the experiments, medium was replaced by tyrode Hepes buffer added or not with nicotine at different concentrations (0.05,0.5, 5, 50 or 200 ug/ml). Basal production of PGI2, assessed after 20 minutes, was significantly increased by 0.5 ug/ml nicotine (223% of control) ; subsequently thrombin (1 U/ml) stimulated release was measured after 5 minutes, it was dose dependently decreased by nicotine. Thus, at least in basal conditions, nicotine treatment of HUVEC alone in culture did not permit us to reproduce the inhibitory effects described on models involving smooth muscle cells in addition to the endothelial cells. Otherwise, nicotine could interfere with stimulating agents such as thrombin. Investigations on the effect of these agents in combination are currently in progress

Proliferation studies : Cells were grown in nicotine or control medium. Proliferation ability, estimated by the increase in cell number at daily interval was slighly increased in cultures receiving 0.05 ug/ml nicotine (110.4% of control). This tendancy was confirmed by 3H Thymidine incorporation (+41%). On the contrary a decrease in cell density was observed for the highest concentrations, from 50 ug/ml. This later effect did not seem to be related to any cytotoxicity or cell detachment. Thus, endothelial cells appeared to be highly responsive to nicotine in their PGI2 production while their growth characteristics were rather resistant to nicotine treatment.
RELATIVE SENSITIVITY OF CARDIAC PROSTACYCLIN AND THROMBOXANE TO INHIBITION BY NON-STEROIDAL ANTIINFLAMMATORY DRUGS IN THE RAT HEART
Authors: Giannessi D , De Caterina R , Lazzerini G , Sicari R , Gazzetti P
Published: August 2018

We have previously shown that the isolated perfused rat Langendorff heart is able to synthesize detectable amounts of thromboxane (TX) A2, as well as prostacyclin (PGI2). Eicosanoid production in this system is increased during post-ischemic reperfusion, reflecting greater availability of substrate and net increase of synthesis. We assessed relative sensitivity of cyclooxygenases synthesizing TX and prostacyclin (probably located in different cell types) to aspirin (0.1, 0.5, 1 g/1), ibuprofen (1, 10, 80, 160, 320 mg/1) and diclofenac (0.01, 0.1, 0.5, 2.5, 5, 10, 25 mg/1), by radioimmunoassays of TXB2 and 6-keto-PGFα in the perfusate. Sixty Wistar male rat hearts were perfused with buffer containing control vehicle or drugs for 30 min, followed by 5 min clamping of the perfusion line and subsequent post-ischemic reperfusion. Baseline production was (mean±SD, pg/min/g wet weight) 754±261 and 143±66 for PGI2 and TXA2, respectively. Peak post-ischemic production was 7628±2673 and 1036±135, respectively. At doses of aspirin, ibuprofen and diclofenac (100, 10 and 2.5 mg/1, respectively) which were equally effective on prostacyclin production (mean % inhibition: 68, 67 and 72 for basal production and 90, 86 and 85 for peak post-ischemic production, respectively), % inhibition of TX production was consistently less, but also similar for the three drugs: 55, 58 and 56 for basal production and 78, 81 and 76 for peak post-ischemic production, for aspirin, ibuprofen and diclofenac, respectively; difference between inhibition of prostacyclin and TX: P < .01, difference for subsets among different drugs: N.S.). TX production was, on the contrary, selectively inhibited by the TX-synthase inhibitor 0KY 046 (by 79 and 92% at 0.1 mg/1, versus a complete sparing of prostacyclin production). The lesser sensitivity of cardiac (vascular?) TX versus prostacyclin to non-steroidal antiinflammatory drugs (NSAIDs) inhibition and the similar degree of inhibition by various NSAIDs, differing in structure and diffusing capacity, suggest heterogeneity among cyclooxygenases present in the system and different intrinsic sensitivity of TX- from prostacyclin-producing cyclooxygenases.