bluuebunny/crossref_metadata_2025 huggingface dataset:
Discordant Expression of Tissue Factor Antigen and Procoagulant Activity on Human Monocytes Activated with LPS and Low Dose Cycloheximide
Authors: Walsh John D , Geczy Carolyn L
Published: July 2018

The mechanisms underlying the superinduction of procoagulant activity by cycloheximide (CHX) on LPS-activated human monocytes have been investigated. Tissue factor (TF) activity of intact, viable cells was quantitated with a plasma recalcification assay and assays using chromogenic substrates specific for thrombin and factor Xa (FXa). TF antigen was measured simultaneously by immunocytochemical staining and immunoblotting with an anti-TF monoclonal antibody (MAb). Peripheral blood mononuclear cells (PBMC) activated with LPS in the presence of low dose CHX expressed more TF activity (approx. 100% increase) than cells activated with LPS alone. However, TF antigen levels were decreased approximately 70% by CHX. This discordant relationship was due primarily to differences in rates of activation of factor X (FX); LPS/CHX-treated PBMC activated nearly twice as much FX as LPS-treated cells (2.19 ± 0.37 versus 1.10 ± 0.21 ng FXa/106 PBMC/min, respectively). These studies indicate that TF cofactor activity on LPS/CHX-treated monocytes was approximately 7 times greater than that present on LPS-treated cells. Increased TF functional activity may be due to CHX-induced alterations in the type and content of phospholipids (PL) in the cell membrane. Results showed that exogenous mixed PL markedly increased TF activity on LPS-activated monocytes, but not on LPS/CHX-activated cells, without increasing TF antigen levels or altering cell viability. Membrane alterations may occur on monocytes in certain pathological or iatrogenic conditions resulting in a highly active form of TF in vivo.
Functional Ca2+ Channel Produced by Purified Platelet Membrane Glycoprotein IIb-IIIa Complex Incorporated into Planar Phospholipid Bilayer
Authors: Fujimoto Tetsuro , Fujimura Kingo , Kuramoto Atsushi
Published: July 2018

The ability of the platelet membrane glycoprotein (GP) IIb-IIIa complex to function as a Ca2+ channel was investigated by electrophysiological methods. The GPIIb-IIIa complex was purified with an electrically silent detergent, CHAPS, and reconstituted into liposomes. After incorporation of these liposomes to a planar phospholipid bilayer, Ba2+-permeable channel currents were detected. Since neither residual detergent nor dissociated GPIIb and IIIa produced any currents, the observed channel currents were attributed to the GPIIb-IIIa complex. These channel currents showed similar electrical properties with the Ca2+ channel previously described in platelet plasma membrane; a single channel conductance of approximately 10 pS in 53 mM Ba2+ solution and voltage-independency. It was concluded that the purified GPIIb-IIIa complex can act as a divalent cation-permeable channel in the artificial phospholipid bilayer.
The Action of a Synthetic Pentasaccharide on Thrombin Generation in Whole Plasma
Authors: Béguin S , Choay J , Hemker H C
Published: July 2018

We investigated the effect on thrombin generation in plasma of the pentasaccharide that represent the AT II/binding site in heparin. This compound has no effect on the breakdown of thrombin in plasma. It dose-dependently inhibits the formation of thrombin in both the intrinsic and the extrinsic pathway. If coagulation is triggered by the complete prothrombinase complex (phospholipid – factor Va – factor Xa) under conditions in which the large majority of factor Xa is bound to the complex, the inhibition of prothrombinase activity is only minor. If no factor Va is present or if the prothrombinase activity is triggered by adding complete tenase (PL-FVIIIa-FIXa) or incomplete tenase (PLFIXa) to the plasma the inhibition by pentasaccharide is of the same magnitude as that in the intrinsic or extrinsic system.

We conclude that the pentasaccharide inhibits blood coagulation by katalysing the inactivation of free factor Xa. In contrast to classical heparin it does inhibit the peak of thrombin formation in platelet rich plasma, probably because it is less subject to inactivation by heparin binding proteins from platelets than classical heparin is.
Involvement of 5-Hydroxytryptamine in Platelet Aggregation In Vivo in Rats and Guinea Pigs
Authors: Smith G M
Published: July 2018

In this study, 5-hydroxytryptamine (5-HT) caused a dose- dependent fall in the circulating platelet count suggesting that 5-HT receptors are activated in rat platelets to cause platelet adhesion and aggregation. When low doses of adenosine diphosphate (ADP) were simultaneously injected with 5-HT, there was a significant potentiation of the responses to ADR Ketanserin significantly reduced the potentiated responses. When higher doses of ADP were infused with bolus injections of 5-HT there was no potentiation and ketanserin did not reduce these responses. Ketanserin did not inhibit the collagen-induced fall in circulating platelet count, but did significantly increase the rate of return to the basal platelet count compared with control. 5-HT did not cause a fall in platelet count in guinea-pigs
Characterization of N,N’-bis(3-Picolyl)-4-Methoxy-Isophtalamide (Picotamide) as a Dual Thromboxane Synthase Inhibitor/Thromboxane A2 Receptor Antagonist in Human Platelets
Authors: Gresele P , Deckmyn H , Arnout J , Nenci G G , Vermylen J
Published: July 2018

Picotamide (G137 or N,N’-bis[3-picolyl]-4-methoxy-iso- phtalamide), a drug which has shown platelet inhibitory effects in vitro and ex vivo, was investigated for its mechanism of action on human platelets in vitro. This compound suppresses the aggregation of human platelets induced by arachidonic acid (IC50: 1.8 × 1(T5 M), low-dose collagen (IC50: 3.5 × 10-4 M), U46619 (IC50: 1.4 × 10-4 M) and by authentic TxA2 (IC50: 1 × 10-4 M), without affecting the aggregation induced by A23187 or primary aggregation by ADP. Picotamide inhibits dose-dependently TxA2 synthesis by platelets (IC50: 1.5 × 10-4 M) and enhances the formation of PGE2. Picotamide-treated platelets also favour the formation of PGI2 by aspirinated endothelial cells; in addition, the drug appears to exert a direct stimulatory effect on PGI2- synthesis, at least at high concentrations. Finally, in platelet-rich plasma stimulated with arachidonic acid, picotamide increases intraplatelet cAMP while no effects on cAMP are detected in unstimulated platelets.

In conclusion, picotamide is a dual thromboxane-synthase inhibitor/thromboxane-receptor antagonist in human platelets and introduces a new class of agents potentially useful in antithrombotic therapy.
Studies on a Subcellular System for Vitamin K- Dependent Carboxylation
Authors: Wallin R , Prydz H
Published: July 2018

The subcellular localization of acarboxyprothrombin and the vitamin K-dependent carboxylation system has been studied using livers from vitamin K-deficient rats and found to be mainly in the membranes of the rough microsomal fraction. Bovine acarboxyprothrombin or fragment 1 thereof were inactive as substrates in the rat carboxylating sytem.
Unbalanced Coagulation-Fibrinolysis Potential during L-Asparaginase Therapy in Children with Acute Lymphoblastic Leukaemia
Authors: Semeraro N , Montemurro P , Giordanol P , Schettini F , Santoro N , De Mattia D , Giordano D , Conese M , Colucci M
Published: July 2018

Treatment of acute lymphoblastic leukaemia (ALL) with L-asparaginase (L-asp) may be associated with thrombotic complications, but the pathogenetic mechanisms of thrombus formation and persistence remain unclear. We studied the procoagulant activity (PCA) of peripheral blood mononuclear cells and some components of the plasma fibrinolytic system in L0 children with ALL undergoing remission induction therapy which includes L-asp. Mononuclear cells obtained 14 days after starting L-asp treatment generated significantly higher amounts of PCA (identified as tissue factor) than cells isolated before the first dose of L-asp and 7 days after the cessation of L-asp administration (p <0.01). Augmented PCA coincided with an increase in the plasma D-dimer. The plasma levels of type 1- plasminogen activator inhibitor were found signiticantly elevated during L-asp therapy (p <0.05), whereas plasminogen levels were markedly decreased (p <0.05). These findings suggest that, during the course of L-asp treatment, the coagulation-fibrinolysis balance is shifted towards promotion of fibrin formation and deposition. Although it remains to be conclusively established whether Lasp per se or the concurrent administration of multiple chemotherapeutic agents is responsible for these changes, the latter could contribute to the thrombotic complications associated with remission induction therapy for ALL.
Monoclonal Antibodies Specific for a Conformationally Altered State of Fibrinogen
Authors: Zamarron Concepcion , Ginsberg Mark H , Plow Edward F
Published: July 2018

Four monoclonal antibodies were selected by their ability to discriminate surface-bound from soluble fibrinogen. These antibodies reacted with insolubilized fibrinogen but not other immobilized proteins and their reaction with surface-bound fibrinogen was not diminished by a 100-fold excess of sotuble fibrinogen. The antibodies reacted with the same or spatially proximal epitopes, and the recognized epitope(s) resided within the gamma chain segment of the D domain of fibrinogen. Fab fragments of the antibodies inhibited fibrin polymerization in a dose dependent manner, suggesting that the epitope(s) was also exposed by the conversion of fibrinogen to fibrin. These data indicate that adsorption of fibrinogen onto a surface induces conformational changes and that similar changes are also evoked when fibrinogen is converted into fibrin.
Azidothymidine (AZT) in the Treatment of Symptomatic HIV-1-Infected Hemophiliacs
Authors: Eichinger S , Pabinger I , Hartl H , Stain C , Mayerhofer S , Schweiger C , Kier P , Schwarzinger I , Kyrle P A , Lechner K
Published: July 2018

Twenty-one immunodeficiency virus 1 (HIV 1)-positive hemophilic patients were treated with Azidothymidine (AZT) for symptomatic HIV infection. The median observation period was 20.5 months.

At 25 months the probability of survival was 82%, the probability of progression of disease from CDC III or IV C2 to IV C1 (AIDS) was 20% in patients on continuous AZT treatment and 50% in patients with intermption of treatment. Three patients developed severe leukopenia and 3 patients severe anemii during AZT treatment. In 1 patient a dose-dependent striking increase of transaminases during AZT treatment was observed. In 7 patients treatment was intermpted, in 1 patient because of anemia, in 1 because of pruritus and in 5 patients because of noncompliance.

No signiticant changes in the consumption of clotting factor concentrates and number of bleeding episodes before and during AZT treatment were noted.

We conclude, that both hematological and non-hematological side effects of AZT in HIV 1-infected hemophilic patientr ur. comparable to those seen in other risk groups . AzT does not increase the bleeding tendency in this patient group.
Solvent Extraction of Test Plasmas for Improved Recovery of Lupus Anticoagulant Activity
Authors: Exner Thomas , Papadopoulos George , Sahman Nilgun , Koutts Jerry
Published: July 2018

Phospholipid procoagulant material mainly derived from platelets interferes or “bypasses” the more specific tests for lupus anticoagulants. Such material in test plasmas can be inactivated with recovery of lupus anticoagulant activity by simple extraction with chloroform. This solvent treatment damages mainly factors VIII, V, VII and IX. Ether and various other solvents were less damaging to these clotting factors but not quite as effective as chloroform in the recovery of lupus anticoagulant activity.
Plasminogen Activator Inhibitors Type 1 and Type 2 and Plasminogen Activators in Amniotic Fluid during Pregnancy
Authors: Estellés Amparo , Gilabert Juan , Andrés Cristina , España Francisco , Aznar Justo
Published: July 2018

Plasminogen activator inhibitor activity (PAI), PAI-1 and PAI-2 antigen, and other fibrinolytic parameters were evaluated in amniotic fluid during normal pregnancy and compared with that obtained in plasma of pregnant women. The results indicate the presence of both PAI-1 and PAI-2 in amniotic fluid during normal pregnancy. In amniotic fluid, PAI-1 antigen levels increased from 194 ± 109 ng/ml (first trimester) to 640 ± 396 ng/ml (third trimester) and PAI-2 antigen levels increased from 72 ± 57 ng/ml to 173 ± 97 ng/ml. In contrast, a decrease in tissue-type plasminogen activator (t-PA) antigen level was observed during pregnancy. The PAI-1 levels in amniotic fluid were significantly higher than the PAI-1 levels in plasma of women at a similar gestational age. However, PAI activity, measured using single chain t-PA, was lower in amniotic fluid than in plasma of normal pregnant women. The PAI activity/PAI-1 antigen ratio in amniotic fluid after activation by a denaturing agent increased from 0.003 ± 0.004 to 0.059 ± 0.018. These results indicate that high levels of PAI-1 are present in amniotic fluid and suggest that this PAI-1 is present in a latent form that can be reactivated, at least partially, by a denaturing agent.
Identification of Dense Granule Specific Membrane Proteins in Bovine Platelets that Are Absent in the Chediak-Higashi Syndrome
Authors: Meyers Kenneth , Seachord Carrie
Published: July 2018

Platelets from cattle with the Chediak-Higashi syndrome (CHS) have a platelet dense granule deficiency. One hypothesis for the platelet dense granule deficiency is that the granule is simply not formed in CHS megakaryocytes (MK). Alternative hypotheses include that the granule is assembled in CHS MK but a functional amino-nucleotide-cation storage complex cannot be formed or that the dense granule or its precursor fuses with other granules. This study was undertaken to determine if membrane proteins specific for platelet dense granules can be identified in membranes of other granules in CHS platelets. Platelets were disrupted; a mixed-granule fraction and alpha-granule enriched, mitochondrial-enriched, and dense granule-enriched subfractions were obtained. Membrane proteins in these intact granules were radiolabeled and the granule underwent hypotonic lysis. Membrane proteins were extracted from granule “ghosts”, separated, and then visualized by autoradiography. Three major proteins were identified in platelet dense granule membrane subfractions. Two of these proteins could be identified in membrane extracts from the mixed-granule fraction from normal platelets. They could neither be identified in extracts from the mixed granule fraction of CHS platelets nor in membranes from alpha granule-enriched and mitochondrial-enriched subfractions. The absence of dense granule membrane proteins in membranes of other organelles within CHS platelets suggests that fusion of dense granules or its precursor with other granules cannot account for the platelet dense granule deficiency in CHS platelets.
Formation and Persistence of Procoagulant and Fibrinolytic Activities in Circulation after Strenuous Physical Exercise
Authors: Hansen John-Bjarne , Wilsgård Line , Olsen Jan Ole , Østerud Bjarne
Published: July 2018

Seven healthy male volunteers were subjected to exercise of short (STR; 1.7 km), middle (MTR; 4.8 km) and long (LTR; 10.5 km) term runs at a speed close to maximal capacity. Blood samples were drawnbefore, immediately after exercise and at intervals over the next 10 h. FVTIIR: Ag (von Willebrand factor) rose 2.2–3.2 fold and persisted at higher levels than baseline during the observation time. A spontaneous drop in FVII (p <0.03) was found immediately after STR(13.5 ± 2.5%) and LTR (18.3 ± 2.4%), whereas only a minor decrease (7.5 ± 6.5%) occurred in MTR. The procoagulant activity of monocytesisolated from whole blood exposed to LPS showed a striking enhancement in STR and MTR. An immediate enhancement in fibrinolytic activity was found in all groups (p <0.03) assessed by increased plasma levels of t-PA and shortened whole blood clot lysis time (WBCLT). The transient shortening of WBCLT was succeeded by a tendency to prolongation of the lysis time. A 45-year old male differed markedly from the others by demonstrating an extreme and consistent prolongation of WBCLT. Thus, it hasbeen speculated that strenuous exercise possibly makes a subject more susceptible to a thrombotic event.
Identification of Platelet Antigens by Immunoprecipitation of Unlabelled Platelet Glycoproteins
Authors: Stenziger Werner , Kehrel Beate , van de Loo Jürgen
Published: July 2018

A time-saving and sensitive method for the identification of antigens on unlabelled platelet glycoproteins (GP) based on immunoprecipitation has been developed. Platelet solubilisates
were incubated with antibodies to form GP-antibody complexes that were precipitated with Protein G Sepharose 4 Fast Flow (PGS). Pcs-bound material was eluted, separated by SDSPAGE under reducing conditions and visualized by silver staining. The method was designed as an alternative to radioimmunoprecipitation
for laboratories not equipped to work with radioactive substances. It is proposed as a complementary procedure for the characterization of platelet GP antigens by murine monoclonal antibodies and human alloantibodies.
Properties of Thrombolytic Agents in Vitro Using a Perfusion Circuit Attaining Shear Stress at Physiological Levels
Authors: Nishino N , Scully M F , Rampling M W , Kakkar V V
Published: July 2018

A perfusion circuit was designed to investigate in vitro some of the factors which may influence the success of thrombolytic treatment in vivo. The rate of lysis of clotted plasma and different types of artificial thrombi (fibrin thrombi or whole blood thrombi) was measured in citrated plasma or whole blood under static conditions or under shear stress equivalent to the arterial or venous circulation. With both streptokinase (SK) and tissue-type plasminogen activator (t-PA) the rate of lysis of fibrin thrombi and whole blood thrombi was reduced significantly, when compared to the conventional plasma gel clot model (25-fold and 8fold, respectively). This occurred particularly with SK which showed a reduction (4-fold) in potency relative to t-PA under these conditions. Lysis of thrombi by both activators was observed to be faster in plasma than whole blood, and also faster with whole blood thrombi than fibrin thrombi. High shear stress, generally, caused a reduction in the rate of lysis of fibrin thrombi and an increase in the rate of lysis of whole blood thrombi compared to lysis rates under static conditions. Under all conditions of flow the lysis rate observed at 50 units t-PA per ml was much faster than that at 500 units per ml unlike the conventional plasma gel clot model.
The Platelet Extinction Coefficient Measured by Aggregometry Is Dependent on Platelet Composition rather than Size: Implications for Studies of Platelet Heterogeneity and Abnormalities
Authors: Frojmovic Mony M , Wong Truman
Published: July 2018

Extinction (E) or light transmission measurements of platelet suspensions have been widely used to evaluate platelet structure and aggregation for platelet populations of varying mean platelet size (V). However, useful comparisons of platelet suspensions from donors having abnormally-sized platelets with those from healthy controls require a knowledge of the dependence of E on V. We have analyzed the extinction per platelet (e) as a function of the geometric scattering cross-section of equivalent spheres, V2/3, related to the apparent mean platelet optical efficiency, k. Such an analysis using data previously reported by Holme et al., for healthy controls and a variety of platelet-associated disorders showed e/V2/3 or k to be constant over an eight-fold variation in V. The outstanding exception was platelet suspensions from myeloproliferative disorder patients (MPD) which showed ˜25% reduction in k values. When we analyzed e/V2/3 data for differentsized platelet subpopulations which were isolated by elutriation from healthy donors, we found that k doubled with a doubling in V from small to large platelets. It appears that the use of aggregometry devices with wide light acceptance angles yields k values for platelets which are insensitive to variations in V, but rather are sensitive to the expected variations in refractive index associated with distinct platelet internal composition and organization expected for different-sized normal subpopulations and “diseased” platelets as found in MPD. We relate these observations to photometric studies of platelet heterogeneity and of aggregation of platelets with different V and k values.
B Cell Dysfunction in Haemophilia in the Absence and Presence of HIV-1 Infection
Authors: Madhok R , Gracie J A , Forbes C D , Lowe G D O
Published: July 2018

56 haemophiliacs selected on the basis of HIV-1 antibody status, liver disease grade and mean annual dose of clotting factor concentrate used were studied. Spontaneous and stimulated IgG and IgM production in vitro were measured. HIV-1 infection was associated with increased spontaneous immunoglobulin production and an impaired response to pokeweed mitogen and Staph Aureus protein A. Implying a shift in the proportions of partially and fully activated B cells.

In the absence of HIV-L infection there was a shift to a greater proportion of partially activated B cells in patients with severe liver disease. The remainder had in vitro immunoglobulin production comparable to controls. B cell abnormalities occur early in the course of HIV-1 infection. Liver disease and not clotting factor concentrate treatment cause B cell abnormalities in the absence of HIV-1 infection in haemophilia.
Electroimmunoassay of Plasma Subunits-A and -S in a Case of Congenital Fibrin Stabilizing Factor Deficiency
Authors: Barbui T , Cartei G , Chisesi T , Dini E
Published: July 2018

Antigenic material related to the fibrin stabilizing factor (Factor XIII-FSF) has been found in all the examined patients with congenital deficiency, albeit in reduced amount.

Recently, Bohn et al. (1973) and Israels et al. (1973) showed that plasma Factor- XIII is composed by two subunits, A (or a) and S (or b); the former active protein, the latter probably FSF-binding protein.

Using specific anti-S and anti-A antisera the Authors found, in a case of congenital deficiency of factor XIII, absence of subunit A. Subunit S presented abnormal behaviour as demonstrated by means of quantitative immunoelectrophoresis according to Laurell.
Hypercoagulability State in Patients with Chronic Obstructive Pulmonary Disease
Authors: Alessandri Cesare , Basili Stefania , Violi Francesco , Ferroni Patrizia , Gazzaniga Pier Paolo , Cordova Corrado ,   C.O.B.H. Group
Published: July 2018

Since there is some clinical evidence that the clinical course of patients with chronic obstructive pulmonary disease (COPD) may be complicated by thrombosis in the pulmonary vessels, we studied whether a hypercoagulability state (HS) does occur in COPD. Plasma levels of prothrombin F1+2 fragment, a marker of thrombin generation, D-dimer, a marker of in vivo thrombin and plasmin activation, and fibrinogen were measured in 37 COPD patients and in 30 controls matched for sex and age. COPD patients had significantly higher values of F1+2 (p = 0.0001) and fibrinogen (p = 0.0005) than healthy subjects. The difference persisted after excluding smoking patients. F1+2 was not correlated with PaO2 (r = 0.02, p >0.05) and PaCO2 (p = 0.12, p >0.05). In six patients with stable COPD and F1+2 greater than 1.65 nM (mean + 2SD of controls) subcutaneous calcium-heparin therapy (5000 IU t.i.d. for 15 days) significantly reduced F1+2 (p = 0.03) and PaCO2 (p = 0.01). This study shows that COPD patients have an ongoing prothrombotic state which could potentially account for thrombosis occurring in pulmonary vessels. The effect of calcium-heparin treatment on clotting system activation and blood gas may suggest this treatment as potential candidate for prospective study in COPD patients.
Effects of DX-9065a, an Orally Active, Newly Synthesized and Specific Inhibitor of Factor Xa, against Experimental Disseminated Intravascular Coagulation in Rats
Authors: Yamazaki Masahide , Asakura Hidesaku , Aoshima Keiji , Saito Masanori , Jokaji Hiroshi , Uotani Chika , Kumabashiri Ichir , Morishita Eriko , Ikeda Takayuki , Matsuda Tamotsu
Published: July 2018

We investigated the protective effects of DX-9065a, an orally active, newly synthesized and specific inhibitor of factor Xa, against two kinds of experimental disseminated intravascular coagulation (DIC) in rats. Endotoxin-induced experimental DIC was induced by a 4-h sustained infusion of endotoxin at a dose of 100 mg/kg. Thromboplastin-induced experimental DIC was induced by a bolus injection of thromboplastin at a dose of 150 mg/kg. The rats were orally administered DX-9065a at 10, 30 or 100 mg/kg 30 min before endotoxin or thromboplastin injection.

In both DIC models, DX-9065a showed a protective effect against DIC, at all doses and in all parameters, including fibrin/fibrinogen degradation products (FDP), fibrinogen level, prothrombin time, activated partial thromboplastin time, platelet count and the number of renal glomeruli with fibrin thrombi.

When DX-9065a was orally administrated at 100 mg/kg without endotoxin or thromboplastin, no significant changes were seen in hemostatic parameters except PT and APTT, and no fibrin thrombi or abnormal bleeding were seen in renal specimens.

These findings suggest that the new oral anti-Xa drug, DX-9065a, has an effect in reducing the severity of DIC. However, further dose-finding and safety studies of this drug have still to be assessed.
Elevated Thrombomodulin Plasma Levels as a Result of Endothelial Involvement in Plasmodium falciparum Malaria
Authors: Hemmer Christoph J , Bierhaus A , Riedesel J v , Gabat S , Liliensiek B , Pitronik P , Lin J , Grauer A , Amiral J , Ziegler R , Schieffer S , Kern P , Seitz R , Egbring R , Dietrich M , Nawroth P P
Published: July 2018

We used thrombomodulin (TM) to assess the participation of the vascular endothelium in human Plasmodium falciparum (P. F.) malaria. Before therapy TM plasma levels were elevated in P. F. malaria and fell to normal values during therapy. Parasitemia, TNFα, elastase and TAT levels correlated directly with TM. Elevated TM levels can not be explained by increased synthesis, since incubating HUVEC with pretherapy serum of patients with P. F. malaria, but not reconvalescence serum, suppressed TM transcription. This was partially prevented by adding a TNFα neutralizing antibody to patient serum before incubation with HUVEC. However, TNFα does not release TM from cultured HUVEC in vitro. Coincubation of HUVEC with pretherapy serum together with neutrophils resulted in endothelial cell destruction, which could be partly prevented by a TNFα neutralizing antibody. Hence the increase of TM during P. F. malaria might reflect the concerted action of cytokines and neutrophils on HUVEC.
Low-Dose Heparin Or Aspirin-Dipyridimole In Prevention Of Postoperative Deep Venous Thrombosis
Authors: Kennedy J H
Published: July 2018

Venous thrombosis and pulmonary embolism remain a serious threat to postoperative patients. Kakker et al have reported favorable effects of low-dose heparin in a prospective study in 4,121 patients in 23 hospitals.

In a prospective randomized study, between May 1978 and August 1980, 375 patients were collated into 7 groups 146 were excluded because of a contraindication to Heparin or lack of general anesthesia; those over 45 vho received a general anesthesia were given either 2,500 u Heparin with premedication and daily until discharge (Group V) or 1 Gram Aspirin-100 mgm Dipyridimole on the same schedule (Group VI); the remainder served as controls.

The results supported protective treatment of over 45 who receive a general anaesthetic and surgery; in unteated patients there were 6 nonfatal thrombotic episodes in 1397 patient-days at risk, but none in either treatment group., together totalling 756 patient- days at risk for the Heparin group and 238 patient-days at risk for the Aspirin-Dipyridimole group.
Systematic Use Of Heparin In The Continuous Flow Centrifuge (CFC) For Blood Cell Separation
Authors: Morales M R , Pizzuto J , Reyna Ma , Castro G
Published: July 2018

To date the use of heparin in the CFC has not been adequately controlled, thus exposing donors and patients to coagulation disorders. For this reason, we decided to evaluate the use of heparin by continuous infusion in dosages that would be modified by a simultaneous assessment of its anticoagulant effect, as shown by the thrombin time dilution test (TTDT).

The study was performed during 46 leukopher- esis and 27 plasmapheresis. It was ascertained that heparin is an efficient anticoagulant in the CFC, using the TTDT as an effective and reliable method for its control. The initial dose in leukopheresis is one unit per milliliter of blood during the first hour, then half the dose during the next hour, and then a quarter of the dose until the procedure is completed. A TTDT performed every hour will indicate whether the amount of heparin used should be modified. For plasmapheresis, it is neccesary to establish a specific dose in each instance, using the TTDT as described. In most of the subjects, the anticoagulant level was exactly right. There was no case of bleeding or extracorporeal coagulation of the blood.

On the basis of these findings, we recommend the use of heparin in the CFC, applying the results of the TTDT as a guide for its dosage level.
Heparin-Induced Thrombocytopenia
Authors: Caprini J A , Sholder A J , Vagher J P , Mitchell J
Published: July 2018

Review of 6,000 patient records from our laboratory showed 609 individuals who received continuous intravenous infusion heparin therapy for thromboembolic disease. 40/609 (6.5%) of these patients were found to have a platelet count of less than 150,000 cell/mm . Of this group, 34/40 (85%) exhibited thrombocytopenia prior to heparin therapy that was attributable to consumptive coagulopathy in 21/40 (52.5%), sepsis or malignancy in 11/40 (27.5%), and cimetidine or sulfisoxazole in 2/40 (5%). Heparin therapy had no adverse effect on the platelet count in these individuals, and the count returned to normal in surviving individuals if the underlying cause was successfully treated or the offending drug removed.

Only 6/40 (15%) of the patients developed low platelet counts during the course of heparin therapy; this represents 6/609 (0.98%) of the population receiving heparin. The etiology of thrombocytopenia in 5/6 (83%) of the cases was traced to metastatic cancer (3), burn wound sepsis (1), and septic shock (1). Only 1/609 (0.16%) of these patients developed low platelet count that could be attributed to heparin. Thus, the incidence of heparin-induced thrombocytopenia is extremely rare in our hospital population.
Urokinase Therapy Of Deep Vein Thrombosis Of The Lower Limb
Authors: Zimmermann R , Harenberg J , Mörl H , Rieben F W , Götz R
Published: July 2018

The effect of fibrinolytic therapy with urokinase in deep vein thrombosis is not clearly establ- shed so far. Previous communications demonstrated success rates of only 26-33 % of complete and partial recanalization by application of 1 (-2) Mio IU urokinase/24 hours.

In the present study in 80 patients with deep vein thrombosis of the lower limb,urokinase therapy was therefore performed at higher dosages in combination with heparin. After a loading dose of 250,000 IU,urokinase was given at a rate of 1300 IU/kg/h (51 cases) or 2000 IU/kg/h (29 cases). Concomitantly 15-20 U heparin/kg/h were administered. The fibrinolytic therapy was mainly controlled by determination of the thrombin clotting time,aPTT and fibrinogen. The further therapy was adjusted to attain a prolongation of the thrombin clotting time 2-4 times the normal value, the aPTT to 60-100 sec and a reduction of the fibrinogen concentration to 50-100 mg% (Clauss method).The thrombolytic effect was established by repeated phlebography. In recently developed venous thrombosis (<10 days) a complete recanalization could be seen in 50% and a partial success in an additional 26% (dosage regimen 2000 IU/kg/h). Under treatment with a maintenance dosage of 1300 IU/kg/h a complete success rate of 31 and partial successes in 30% of the cases could be observed. Only few serious side reactions were observed.

Our therapeutic results demonstrate that under therapy with higher dosages of urokinase a more pronounced rate of recanalization can be observed. The higher dosage regimen presented here seems to be an adequate schedule in therapy of deep vein thrombosis without an increasing of bleeding.
Urokinase Treatment Of Phlegmasia Cerulea Dolens
Authors: Zimmermann R , Mörl H , Harenberg J , Brockhaus W , Walter E , Diehm C
Published: July 2018

Phlegmasia cerulea dolens is the most severe form of venous thrombotic disease and continues to have a mortality rate of about 10 %. Most of the authors propagate the rapid thrombectomy as an only effective therapeutic regimen. However,the success of the surgical procedure is questionable when older or recurrent thromboses preceded or when a critical general condition does not allow surgery.

In 3 patients (71,76 and 59 years old) with phlegmasia cerulea dolens surgical treatment had been refused. In view of the great age of the first 2 patients fibrinolytic therapy with streptokinase was disaproved. In the third case treatment with streptokinase was performed previously. In all patients thrombolysis with urokinase 2-5 Mio IU/24 h in combination with heparin (25.000-40.000 U/ 24 h) was started. An impressive improvement of the local findings with almost complete normalization of the lower leg could be observed. In the first and third case with already developed necrosis of the forefoot area, a marked regression of the necrosis was attained. A boundary zone amputation became necessary in the first patient while in the third case a spontaneous demarcation of the necrotic area was observed. In the second patient restitutio ad integrum could be attained. The reported cases suggest that fibrinolytic therapy with urokinase constitutes an alternative to venous thrombectomy and thrombolysis with streptokinase even in the most severe form of phlebothrombosis. Treatment with urokinase should be regarded, if contraindications for thrombectomy or thrombolysis with streptokinase are present.
Fibrinolytic Activity In Metastatic Tumors And Tumor Thrombi
Authors: Yuen P , Rwaan H C
Published: July 2018

In an attempt to clarify the conflicting reports of plasminogen activator and lack of fibrinolytic activity in tumor tissues, the fibrinolytic activity of 62 metastatic tumors and 5 tumor thrombi from autopsy and biopsy specimens was studied by the fibrin slide technique. Metastatic tumors involved lymph nodes, liver, lung, brain and ovary. Tumor thrombi were mainly comprised of hepatoma thrombi in branches of either hepatic or portal veins.

The lack of fibrinolytic activity was graded according to the focal lysis time of vascular tissues within the tumor and in the case of lymphnodes, lymphatic channels. A complete lack of fibrinolytic activity was observed in metastatic tumors and tumor thrombi, a finding similar to that observed in primary tumors.

Immunofluorescent studies on the tumors revealed the presence of antigenic material identical to fibrin, platelets and alpha2 plasmin inhibitor.
Comparison Between Vascular Plasminogen Activator Activity And Blood Flow In The Renal Cortex After Induction Of Hemorrhagic Hypotension And Infusion Of Indomethacin Or Saralasin In Pigs
Authors: Smokovitis A , Maier M , Binder B R
Published: July 2018

Patterns of vascular plasminogen activator activity and blood flow were compared in the renal cortex of pigs after induction of hemorrhagic hypotension (1ml blood loss per kg and minute until the death of the animal) and infusion of indomethacin (prostaglandin synthetase inhibitor) or saralasin (competitive inhibitor of angiotensin II). Blood flow was measured by radioactive labelled microspheres. Pigs infused with indomethacin or saralasin during hemorrhage showed by the end of the experiments (mean arterial blood pressure 40-50 mmHg) almost the same decrease in the outer (65-70%) and inner (55-65%) renal cortical blood flow (RCBF) compared to the RCBF values before hemorrhage. However, only in saralasin treated pigs a change in the plasminogen activator activity (PAA) was induced (30% decrease in the inner and 45% in the outer renal cortex). In pigs subjected to hemorrhage and infusion of the corresponding vehicles for the inhibitors the vascular PAA in the renal cortex remained unchanged despite a marked change in RCBF (decrease to 4-7% by the end of the experiments). In indomethacin treated pigs without bleeding RCBF was diminished to 80% of the values before infusion of indomethocain until the end of the experiment (100 minutes infusion of indomethacin); no change in the vascular PAA was seen. In saralasin treated pigs without bleeding RCBF increased initially (20%) and returned to control values until the end of the experiment; the vascular PAA in the renal cortex showed a 15% decrease. Changes in plasmin inhibitor
activity in the renal cortex were not noted.

Under the conditions of these experiments no correlation could be found between induced changes in RCBF and vascular PAA in the renal cortex. The vascular fibrinolytic response to saralasin should be due to an indirect effect of saralasin independent of the changes in RCBF induced by this agent
Factors Influencing The Structure Of Terminal Plasmin Degradation Products Of Human Fibrinogen And Fibrin
Authors: Nieuwenhuizen W , Vermond A , Haverkate F
Published: July 2018

Experiments have been carried out with fibrinogen and with purified degradation products of fibrinogen and fibrin which demonstrate that the structure of D fragments obtained after prolonged plasmin digestion is influenced by several factors in the media.

The previously described protective effect of calcium ions on the γ-chain carboxy-terminals of fibrinogen against plasmin attack is rather independent of the composition of the media (e.g., also observed in 2 M urea and/or high plasmin activities).

Several compounds such as EDTA, EGTA, citrate and iminodiacetic acid appear to have a separate effect, which is best observed at low plasmin concentrations and in the absence of Ca2+ . Under these conditions, these compounds appear to make the γ-chain carboxy-terminal ends of the D- and D-dimer fragments more susceptible to plasmin digestion.

Finally, as demonstrated by experiments with purified D;E complexes from fibrinogen and with whole fibrinogen digests, the E-moiety of the D:E complexes appears to be capable of protecting the D-moiety against low plasmin concentrations also in the absence of calcium ions.
Post Pancreatectomy Alteration Of Hemostatic Parameters In Dogs
Authors: Messmore Harry L , Fareed J , Terem T , Prinz R , Freeark R , Walenga J , Kelly J
Published: July 2018

Alterations in the components of coagulation, fibrinolytic and kallikrein systems, pancreatic enzymes, and physiological inhibitors of serine proteases have been reported after pancreatectomy and may be used as in index of the success of surgical procedure. Post surgical alterations of the components of hemostasis, kallikrein - kinin system and other laboratory parameters were monitored after three established procedures for distal pancreatectomy were performed in dogs. Fifteen animals were subdivided into 3 groups and designated according to the closure technique used: 1) Individual closure of distal end (IC), 2) mass ligation with 0 silk (MLS), and 3) automatic stapler (AS). Blood samples were drawn from the peripheral veins prior to and immediately after surgery, and over a period of 14 days. No alteration in the hemoglobin, hematocrit, red cell indices and platelets were noted in all groups, however, a sharp increase in the leukocytes was noted with a peak at 24 hours post surgery and gradual return to a steady level at 72 hours. A gradual rise in the fibrinogen level was seen in all groups with a peak (2-2 ½ fold base line) at 48 hours, with a gradual return to the original values within 5 days. Prothrombin time, non-activated partial thromboplastin time, thrombin time, reptilase time, progressive antithrombin and antithrombin-III remained unchanged. A marked reduction of antiplasmin, antikallikrein (Glandular) and antitrypsin activities was observed, and a slight reduction in the HMW kininogen was observed. Free kinins were not demonstrable. Although significant increases in the APTT were seen in all groups, the MLS group showed the most pronounced increase. The increase in pancreatic enzymes and elevated APTT are suggestive of some leakage of pancreatic enzymes into circulation, which may contribute to certain post pancreatectomy pathophysiological responses.
Identification Of Membrane-Linked Proteins Acting On Blood Red Cell Filtration. Study In Cerebrovascular Accident And Thrombosis
Authors: Boisseau M R , Lorient-Roudaut M F , Manuau J P , Blanchard P , Crockett R , Bricaud H
Published: July 2018

The blood red cell filtration (RCF) through nucleopore filters(5 μ ø) decrease in cerebrovascular accidents (CVA) and thrombosis. This disorder is related to circulating factors, especially fibrinogen and factor VIII. But after washing it also appears to be related to membrane-1 inked proteins. In this study, isolation and identification of these proteins were realized in patients with increased RCF. Have been here concerned 20 patients with CVA and/or other thrombosis, 8 days after the onset and compared to 30 controls.

After the RC have been washed twice the proteins were eluted from the membrane, concentrated and submitted to usual electrophoresis and immunoelectrophoresis. The identification was made with specific antiserums against factor VIII, fibrinogen, fragments D and E, transferin, coeruloplasmin and using SDS polyacrylamid gel electrophoresis with, as controls, purified fibrinogen, fragments D and E, transferin, coeruloplasmin.

The results were : in controls the eluted proteins are similar with an albumin/globulin ratio (A/G ) > 1. In patients with a high disorder of RCF the proteins were increased, with an inversion of the A/G. Two kinds of proteins were found : (1) a β population composed of inflammatory proteins, mainly transferin, (2), a β-α population consistuted by fibrin-related products. Concerning the whole population of patients with a high disorder in RCF, 80 % exhibited proteins induced by inflammation. In 20 % it was found proteins related to the coagulation, i.e. : fibrin related products. Finally, the disorder of RCF in thrombosis is much more due to these membrane disturbances than to circulating factors. During the clinical care of the patients it also has been observed that pentoxyphiline improved the RCF, certainly acting at the membrane level.
Semi-Automated Determination Of Platelet And Red Blood Cell Loss During Hemostasis In The Guinea Pig
Authors: Szoke M , Willis A L , McGuire R , Fisher J M , Donegan D , Smith D L
Published: July 2018

Male guinea pigs of 350-500 g (Hartley strain, Simonsen, Gilroy, CA) were anesthetized with pentobarbitone sodium (32.5 mg/kg, i.p.) and restrained head downwards on a plexiglass board tilted at an angle of 45° to the horizontal. Both ears were held down on the surface of the board using adhesive tape (Scotch brand #810). The upper surface of each ear was then superfused at 5 ml/min with warmed (37°C) sterile 0.9% (w/v) NaCl solution, delivered via a 14 g hypodermic needle. The tip of the needle was lowered in a standardized manner to puncture a small ear artery. From the time of incision, serial 10 sec. aliquots of bloodstained superfusate were collected into tubes containing 10 ml of particle-free saline with EDTA (‘Isoton’, Coulter) to inhibit coagulation and platelet clumping. After bleeding had ceased, the tube contents were allowed to sediment overnight. The following day, platelets in the upper (plateletrich) layer were counted electronically (Coulter). After shaking and further dilution the red blood cells were similarly counted. Effects of 500U heparin and 20 mg/kg aspirin (i.p., 1h. before bleeding) were examined. Both drugs markedly increased platelet and RBC efflux from the hemostatic site, but with characteristic differences in the time curves observed. An unexpected finding was that an incision in one ear could suppress bleeding from an incision subsequently made in the second ear. A previously undiscovered reflex or blood-borne hormone may be responsible.
Enzymic Cleavage Of In Vivo Formed Maillard-Type Compounds Involved In Haemostasis
Authors: Mester L , Szabados L , Mester M
Published: July 2018

Desoxyfructose derivatives of serotonin (Mester et al.,1975), of haemoglobin (Flückiger and Winterhalter, 1976), of poly-L-lysine (Mester et al., 1975) and of lysine rich histones (Kertesz-Crisba, 1977) are easily formed in vivo by a simple Maillard-type chemical reaction. Some of these compounds interfere with platelet functions (Mester et al.,1976) or contribute to the thickening of the basal membrane of blood vessels (Cerami et al., 1979).

While the chemical synthesis of Maillard-type compounds proceeds readily even in vivo, the chemical cleavage of them needs sever conditions which certainly do not exist in vivo (Gottschalk, 1952). However, a slow liberation of serotonin from desoxyfructo-serotonin is observed in vivo, suggesting the existence of an enzyme system for the cleavage of Maillard-type sugar-amine derivatives. In vitro, using a sheep liver microsomal preparation rich in Cytochrome P450 enzyme, the liberation of serotonin is in linear correlation with the enzyme concentration. The cleavage of desoxyfructo-serotonin is activated by NADPH having its optimum at pH=7.4, excluding definitely the occurence of a chemical hydrolysis.

Factors interfering with the enzyme system involved in the cleavage of Maillard-type compounds, may also interfere with haemostasis.
Venous Function After Postoperative Vinous Thrombosis Diagnosed By The 125I-Fibrinogen Uptake Test (FUT)
Authors: Bergqvist D , Hallböök T , Lindhagen A , Lindroth B
Published: July 2018

The late venous function after a postoperative FUT-detected thrombosis is unsatisfactorily documented. This study evaluated the venous status of legs with and without FUTdetected postoperative thrombosis four to five years later. Material; 50 patients (30 male, 20 female), mean age 70 years (55-4 years), who were operated on with electiv hip surgery or abdominal surgery. All were screened with FUT to detect thrombosis. 21 patients (28 legs) developed postoperative thrombosis. Methods: At follow up a clinical examination was made and a questionaire answered. Strain-gauge plethysmography and distal ambulatory venous pressure were made as well as After Exercise Thermography (AET). In 17 legs venous pressure measurement could not be performed. Results: The clinical examination and subjective symptoms did not differ between FUT-pos. and FUT-neg. legs. 29% of the FUT-pos. legs and 26% of the FUT-neg. legs had indication of deep venous insufficiency in plethysmographic and/or venous pressure recordings. Five patients with FUT-neg. legs and signs of venous insufficiency at follow-up had had a new operation during the observation time, none had had clinical signs of thrombosis. Nine patients had FUT-pos. thrombosis extending above knee, but only one had deep venous insufficiency at follow-up. AET was pos. in 39/91 legs. Of these 9 legs (24%) were FUT-pos.

Conclusion: So far this study, where 250 patients are to be included, has not revealed any difference in follow-up venous function between legs with and without postoperative thrombosis as diagnosed with FUT.