bluuebunny/crossref_metadata_2025 huggingface dataset:
CIRCADIAN VARIATION OP PLASMINOGEN ACTIVATOR INHIBITOR (PAI) AND THE INCIDENCE OP SEVERE ISCHEMIC ATTACKS IN PATIENTS WITH CORONARY ARTERY DISEASE (CAD)
Authors: Huber K , Resch I , Rose D , Schuster E , Glogar D H , Binder B R
Published: August 2018

Recent studies have shown a high incidence for the onset of acute myocardial infarction (AMI) in the morning and a possible role of high plasma levels of plasminogen activator inhibitor for the risk of reinfarction. We therefore investigated the diurnal course of PAI and the incidence of severe ischemic attacks in patients with CAD. Blood was drawn from 64 patients at the coronary care unit with angiographically proven CAD (group A = unstable angina, n=37; age = 60.7 ± 10.1 years; group B = stable angina, n=27, age = 58.2 ± 10.9 years) at 4 different time points (6 a.m., noon, 6 p.m., midnight) for at least 3 consecutive days. PAI (functional titration assay; IU t-PA inhibited/ml) and time of onset of severe ischemic attacks including AMI were determined. 50 healthy volunteers (age = 39 ± 17 years) served as controls. We found a significant diurnal variation (paired t-test, p<0.05) of PAI levels in normals (6 am: 11.5±5.6; noon: 6.9±1.7; 6 pm: 5.7±2.5; x ± SD) as well as in patients (6 am: 15.6 ± 6.4; noon: 13-3 ± 1.2; 6 pm: 12.6 ± 5.3; midnight: 13.2 ± 2.8; x ± SD) with an acrophase at 6 am. Compared to the controls PAI values were significantly higher in patients (p<0.01) but showed no significant differences within the two patients’ groups. We could not demonstrate a significant difference in PAI values of patients with or without previous myocardial infarction. Furthermore, development of AMI had no demonstrable influence on preexisting PAI values in both patients’ groups. During the observation period 90 severe ischemic attacks were observed. Attacks occured significantly more often (70$) between midnight and noon with a peak incidence (44$) around 10 am. From these data it can be concluded that PAI levels are elevated in patients with CAD. Peak levels of PAI seem to precede the ischemic event by only a few hours and might thereby contribute to the onset of ischemic events on a basis of increased thrombotic tendency.
TRANSCORONARY PLATELET ACTIVATION AND CONSUMPTION IN CORONARY ARTERY DISEASE (CAD): STUDIES DURING PACING TACHYCARDIA
Authors: Mant M J , Greenwood P V , Kappagoda C T , Hamacher B C
Published: August 2018

Plasma platelet factor 4 (PF4), beta-thromboglobulin (BTG) and platelet counts (PC) were measured in blood from the aortic root (Ao) and the coronary sinus (CS) in 13 subjects with CAD immediately after atrial pacing to a heart rate of 130/min, to ischemic ECG changes or to angina. The same studies were performed on peripheral vein (PV) blood before and after pacing. Blood was collected before heparinisation. Blood from the Ao and CS was collected through catheters containing an anti-coagulant/antiplatelet solution. This technique has been shown to cause minimal or no platelet activation. Of the 13 subjects, 9 underwent investigation for exertional angina, 3 for myocardial infarction (MI) within 6 months, and 1 subject for both reasons. At coronary angiography after our studies, 9 subjects had hemodynamically significant 2 or 3 vessel CAD with at least 1 vessel of a dominant system and 4 had a lesser degree of CAD. Mean values in blood from the PV before pacing, and from the Ao, CS and PV after pacing were respectively: PF4 (ng/ml) -3.7, 8.8, 10.5, 9.6; BTG (ng/ ml) -17.2, 25.9, 28.7, 25.1; and PC (x109/1) - 213, 206, 200, 209. There was no significant difference (analysis of variance) between means in blood obtained from the Ao, CS and PV after pacing. For PF4 and BTG each of these 3 values was significantly higher than the PV values before pacing. Of the 13 subjects, 5 had angina during pacing. Mean results in these 5 subjects from the Ao and CS were not significantly different and were respectively: PF4 - 9.6 and 12.9-, BTG - 27.9 and 34.0, and PC - 204 and 197. Results in the 8 subjects who did not have angina during pacing were similar, as were results in the 4 subjects who had sustained a recent MI and in the 9 subjects who had not. These results indicate that the presence of the catheters and/or the pacing procedure causes slight platelet activation. However, they provide no support for the hypothesis that transcoronary platelet activation occurs during tachycardia and thus could contribute to angina. They also provide no support for the hypothesis that transcoronary platelet activation occurs during angina in patients with stable CAD, whether as a cause of it or a result.
IMPAIRED FIBRINOLYSIS IN CORONARY ARTERY DISEASE (CAD): INFLUENCE OF AGE AND FAMILY HISTORY (FH)
Authors: Francis R , Kawanishi D , Baruch T , Mahrer P , Rahimtoola S , Feinstein D
Published: August 2018

We assessed fibrinolysis in 99 subjects with CAD documented by angiography. Tissue-type plasminogen activator (tpa) antigen and activity (act) were measured in plasma by ELISA and solid-phase bioimmunoassay, respectively, pre and post venous occlusion (VO) of the arm for 10 minutes. Pre-VO tpa inhibitor (PAI) was assayed by a modification of the method of Juhan-Vague (Thromb Pes 1984). Mean PAI was significantly higher, and mean post-VO tpa act significantly lower, in all CAD subjects than in 28 normals (no CAD by angiography). Mean increase in tpa antigen with VO (releasable tpa) was significantly lower than that of normals only in CAD subjects with age of onset <45. Mean releasable tpa and tpa act post-VO were lower in CAD subjects with age of onset <45 than in older subjects, lower in those with positive than negative FH of CAD in parents or siblings, and lowest in those with both FH and age of onset <45. In contrast, PAI was higher in older subjects. These data suggest that genetic factors may contribute to impaired fibrinolysis in CAD.
EXPERIMENTAL STUDIES ON THE MECHANISM OF CHINESE MEDICINAL RHAPONTICUM UNIFLORUM DC IN PREVENTING CORONARY HEART DISEASE
Authors: Erzhen Zen , Yung-Cai Lu , Jain Wang , Fang Shi , Xiaoqing Lia , Yulin Zhou , Xudong Jia , Zhaozheng Gou
Published: August 2018

The mechanism of Rhaponticum Uniflorum DC in preventing coronary heart disease was studied in vivo and in vitro. TBA fluorescent method was used to determine lipid peroxides (Lpo) and double analysis method was used to determine glutathione peroxidase (GSH-Px) activity and fluorescent polarization of DPH probed membrane fluidity of smooth muscle cell (SMC).

Rabbits were fed with high fat diet for 120 days. At the end of experiment, all the animals acquired hyperlipidemia and developed atheroma lesions in aorta and/or coronary. It was found that hyperlipidemia caused a rising of Lpo in blood (from 2.6±0.56 in control up to 8.48±3.28 nmol/ml) and in arterial wall (from 6.75±0.59 in control up to 31.94±4.20 nmol/g protein) and a decreasing of GSH-Px activity in arterial wall (from 0.210±0.095 down to 0.056±0.026 EU/g protein); concomitantly, an increase in microviscosity of arterial SMC membrane (from 1.93±0.04 in control up to 3.49±0.92 poise) which reflects a decrease in fluidity of SMC membrane. Lpo level was higher in plaque area (113.70±46.14 nmol/g protein) than in non-plaque area (58.32±12.69 nmol/g protein). GSH-Px activity level was lower in plaque area (0.0052±0.0014 EU/g protein) than in non-plaque area (0.015+0.0014 EU/g protein). Microviscosity of SMC membrane was higher in plaque area (2.92±0.35 poise) than in non-plaque area (2.26±0.24 poise, p<0.02). By comparison, the rabbits received Rhaponticum Uniflorum DC and VE showed much lowering of Lpo level in arterial wall (down to 10.74±1.61 and 9.93±1.17 nmol/g protein) and decreasing of microviscosity (down to 2.05+0.45 and 2.08+0.50 poise) that is increasing of membrane fluidity of arterial SMC membrane, but GSH-Px activity in arterial wall was keeping at lower level (0.036±0.027 and 0.051±0.027 EU/g protein). The atheroma lesions develped in these two group animals were less severe and fewer in number.
LEECH PROSTAGLANDINS AND THE ENZYME DESTAB ILASE AS THROMBOLYTIC AGENTS OF THE PREPARATIONS FROM THE MEDICINAL LEECHES
Authors: Baskova I , Nikonov G
Published: August 2018

The thrombolytic effect of the leeching of thromboflebits has been well known from the ancient time. It is provided by the propertiesof the salivary gland secretion though leech saliva does not show proteolytic activity and does not activate plasminogen to plasmin. Butin leech saliva we have found the enzyme destabilase (isopeptidase-glutaminase) which hydrolyze the crosslinked fibrin. This mechanism can be the basis of a new type of fibrinolysis. We have observed the high affinity of destabilase to fibrin that provides the dissolutionof thrombous in circulating citrate blood in experiments in vitro. The high affinity of destabilase to fibrin correlates with its high ability to bound L-lysine, which inhibits isopeptidase and glutaminase activity of destabilase. Using radioimmunoassay for 6-keto-PgF1 we have found prostaglandins in saliva and other preparations from the medicinal leeches:

3400 pg/ml of leech saliva

322 pg/mg of protein (the whole leeches extract)

351 pg/mg of protein (the head region extract)

63 pg/mg of protein (blood from the intestinal tract)

But the leech prostaglandins in contrast to 6-keto-PgF1 has Strongly inhibited platelets aggregation stimulated by thrombin. The leech prostaglandins stimulate thrombolysis in rats after intravenous injection or oral administration. We have supposed that thrombolytic effect of leech prostaglandins is induced by the release of tissue plasminogen activator from vessel wall.

In the experiments on rats it has been shown that thrombolytic effect of leech saliva and preparations from the medicinal leeches is provided by the summary effect of the leech prostaglandins and the enzyme destabilase. After the extraction of prostaglandins by ethylacetate thrombolytic effect is diminished by 4O per cent.
THROMBOLYTIC EFFECTS OF A POLYANIONIC COMPOUND (PENTOSAN POLYSULPHATE SP54 ) IN GERIATRIC PATIENTS
Authors: Vogel G , Machulik M
Published: August 2018

In geriatric patients the use ofstreptokinase or urokinase is oftenlimited by contraindications, particularly hypertension. As it has been demonstrated by different authors, the polyanionic compound pentosanpolysulphate SP 54 induced an activation of both intrinsic and extrinsic pathway of fibrinolysis and produced a mild decrease of blood prssure. From thise characteristics pentosan polysulphate SP54 should be anideal thrombolytic agent in geriatric patients.
To clarify this, an open prospective studie was performed. 24 patient(16 females, 8 males ) age 65 -78 years , suffering from thromboembolicprocesses ( 8 deep vein thrombosis(DVT), 16 thrombosis of reti na vessels ( TRV) were included. Pentosan polysulphat SP 54 (BENE-PHARMA Munchen, F.R.G.) was administred byintravenous infusion 300 mg daily over a period of 10 days. Venographyor ophthalmoskopie were repeated atday 11.

Results:

Side effects: Bleeding 0 ; thrombocytopenia 2

It is concluded from these results, that pentosan polysulphate SP54is an useful thrombolytic agent in particular in geriatric patients suffering from hypertension.
PROPERTIES OF THE COMPLEX BETWEEN ou-MACROGLOBULIN AND THE PROTEINASE BRINASE FROM ASPERGILLUS ORYZAE
Authors: Larsson L J , Frisch E P , Bjoörk I
Published: August 2018

Brinase, a proteinase from Aspergillus oryzae, has previously been shown to have a significant thrombolytic effect in patients suffering from peripheral arterial disease. Brinase is rapidly bound to α1-proteinase inhibitor and α2-macroglobulin (α2M) in plasma. Since binding of a proteinase to α2 M only results in ste-rical blockingof the active siteand not complete inactivation of the enzyme, it has been suggested that brinase in complex with α2M may retain ability to digest fibrin.To test this hypothesis, we have characterized the binding of brinase to α2M and the properties of the complex formed. Analyses by several techniques showed that one molecule of α2M can maximally bind twomolecules of brinase. The bait region and the thioester bonds of α2M were cleaved in this reaction in a similar manner as in the reactionwith trypsin. Moreover, a conformational change highly similar to that-caused by trypsin was induced in oα2M by brinase, as shown by changes of fluorescence emission, far-u.v. circular dichroism and u.v. absorption difference spectra. Thus, brinase appears to bind to α2M in the same manner as other proteinases. The activities of free brinase and two forms of brinase-α2M complex, produced by reaction of thetwo components in an equimolar ratio or by saturation of inhibitor with enzyme, were compared by two different assays with high-molecular-weight substrates, i.e. hide powder azure or fibrin. The complex formed with equimolar amounts of brinase and α2M showed ∼15% of the activity of free brinase in both assays, whereas the complex formed at saturation of inhibitor with enzyme showed ∼35% of the free brinase activity. Although the brinase-α2M complex, like other α2M proteinase complexes, is eliminated rapidly from plasma, the anility of the complex to cleave high-molecular-weight substrates may be an explanation of the thrombolytic effect of brinase seen in patients.
THE COMBINATION OF INCREASED FIBRINOLYTIC ACTIVITY AND REDUCED PLATELET NUMBER AND FUNCTION CONTRIBUTES TO POSTOPERATIVE BLEEDING IN CARDIOPULMONARY BYPASS PATIENTS
Authors: Holloway D S , Summaria L , Sandesra J , Vagher J P , Alexander J C , Caprini J A
Published: August 2018

Both increased fibrinolysis and reduced platelet number and function have been reported postoperatively in cardiopulmonary (CP) bypass patients, but correlations with postoperative bleeding often have not been found. We simultaneously evaluated platelet and fibrinolytic parameters to assess their individual and combined contributions to postoperative blood loss. Plasminogen (pig) concentration, alpha-2-antiplasmin (AP) concentration, free protease activity (fPA), platelet count, and platelet aggregability were measured in nine patients undergoing cardiopulmonary bypass surgery. Hematocrit was also measured in order to determine the degree of blood dilution during CP bypass. Chest tube drainage was used as the measure of postoperative blood loss. Pig and AP concentrations decreased With hemodilution during bypass. fPA did not decrease with dilution but remained at pre-bypass levels. Platelet count decreased during bypass but aggregability to ADP and arachidonic acid (AA) did not change significantly. Following protamine administration there was a large increase (83$) in fPA, the platelet count showed a further drop (from 61% to 50% of pre-bypass levels), and platelet aggregability decreased significantly (from 95% to 34% of pre-bypass levels). Early chest tube drainage (1st 4 hrs postoperatively) correlated positively (p[0.05) with the combination of increase in free protease activity and decrease in platelet count. Total chest tube drainage correlated positively (p[ 0.05) with the combination of increase in free protease activity and decrease in platelet aggregability to ADP. None of the measured parameters individually showed significant correlation with chest tube drainage. In this patient sampling, however, the combination of changes in fibrinolytic activity and changes in platelet function did correlate significantly with chest tube drainage. These data indicate that the increased fibrinolytic activity and the decreased platelet number and function have a synergistic effect on postoperative blood loss in CP bypass patients.
INTEREST OF THE RATIO OF INCREASE OF (β-THROMBOGLOBULIN (Δ+/βTG) AND OF FIBRINOPEPTIDE A (Δ+ FPA) FOR DIAGNOSIS AND TREATMENT OF THR0MB0-EMB0LIC DISEASES
Authors: Lavenne-Pardonge E , Col-De Beys C , Moriau M
Published: August 2018

The interest of release of TG and FPA for the diagnosis and treatment of prethrombotic and thrombotic disorders is well known

The ratio of increase of these two parameters (Δ+βTG/+ FPA) seems to bring some additional informations.

This ratio, normally about 1, increases in isolated or preponderant platelet activation and decreases when platelet activation plays a minor role than the plasmatic factors. A more logical choice of therapeutics and a better control of its effectiveness are so possible.

This study includes 91 cases of established thrombosis (20 arterial and 71 venous) and 272 cases of prethrombotic disorders (58 Raynaud syndromes, 54 cases of venous insufficiency, 60 of hip prosthesis, 40 of coronary by-pass, 60 of valvular replacement). The ratio + TG/ + FPA was calculated before, during and after efficacious or inefficacious treatment. In the cases of established thrombosis, our results confirm the leading role of platelets in the development of arterial thrombosis. The cases of venous thrombosis may be divided in two groups : simple venous thrombosis when the plasmatic factors play a leading role and complicated or recurrent venous thrombosis where the platelets play an equivalent or even a greater role.

In the cases of prethrombotic states, the role of the platelets which is important on the arterial side is generally far from negligeable on the venous side. In cases of valvular replacement or of coronary by-pass the modification of the ratio lead us very frequently to modify our prophylactic therapeutics
DETERMINATION OF SOLUBLE FIBRIN IN PLASMA WITH A CHR0M0GENIC KIT METHOD UTILIZING THE HIGH AFFINITY PLASMIN SUBSTRATE S-2390
Authors: Ersdel E , Andersson M , Rosen S
Published: August 2018

A sensitive and quantitative assay of soluble fibrin is of clinically diagnostic relevance in an early thrombotic state where there is a risk for development of DIC. Recently Wiman and Ranby (Thromb. Haemostas 55, 189-193 (1986)) published a spectro-photometric assay which met these criterions. The single-stage assay procedure is based upon activation of Glu-Plasminogen to Plasmin by t-PA in the presence of soluble fibrin and hydrolysis of the chromogenic plasmin substrate S-2390, H-D-Val-Phe-Lys-pNA, which has a high affinity for plasmin. The rate of plasmin generation is correlated to the amount of soluble fibrin monomers present in the sample.

A complete kit containing optimized, stable reagents has now been developed which allows a quantitative determination of soluble fibrin in the range 30-200 nmol/1 within 30 min. at room temperature (20-25°C). The assay procedure is straightforward involving addition of 200 pi diluted plasma sample to 200 pi Glu-Plasminogen and 100 ul of a t-PA/S-2390-reagent.

The results show a high resolution of the standard curve as illustrated by a AA405 amounting to about one absorbance unit between a 200 nmol/1 sample of soluble fibrin and the reagent blank, some variation, ±0.1 absorbance unit, being caused mainly by differences in temperature. In combination with an intra-assay variation coefficient = 6.3% and 5.0% at 150 and 50 nmol/1, respectively, this will allow safe and reliable differentiation of pathological levels of soluble fibrin from levels found in healthy subjects (below 10 nmol/1). A similar precision is also obtained when the assay is performed in microplates.

In the original procedure fresh frozen human plasma was utilized as a dilution medium for soluble fibrin. Comparisons with carefully collected bovine plasma proved this source to be a convenient substitute. Furthermore, lyophilization of the bovine plasma did not produce any significant degradation of fibrinogen which otherwise might interfere in the assay. This simple kit procedure should make it a suitable tool in early determinations of soluble fibrin in a number of pathological states which may result in severe haemostatic disturbances.
QUANTIFYING DETERMINATION OF SOLUBLE FIBRIN BY MEANS OF TURBIDI-METRY OF THE PROTAMINE SULFATE PARACOAGULATION
Authors: Wieding J U , Eisinger G , Kostering H
Published: August 2018

A new method has been elaborated that shows a high sensitivity for soluble fibrin (SF) in plasma without disturbing sensitivity for fibrinogen; the aggregation of soluble fibrin by protamine sulfate (PS) leads to a turbidity of the plasma sample which is measured by means of turbidimetry.

To evaluate the test conditions, plasma samples with high levels of fibrinogen and soluble fibrin were analysed, varying pH value, concentration of plasma and PS, wavelength and timing of the analysis.

The SF-PS-turbidimetry correlated well with the fibrinopeptid A levels in plasma samples with thrombin induced fibrinogen-fi-bri n-transformation.

This method is characterized by its good practicability, prompt availability of reproducible quantifying results and its economy in single and serial analysis.

Analysis of plasma samples from 2000 patients demonstrated the good validity of the new method; it is qualified for routine diagnostics of hypercoagulability with increased fibrinogen turnover.
COMPARISON OF HUMAN AND RABBIT BRAIN THROMBOPLASTIN IN THE EVALUATION OF LIVER DISEASE
Authors: Kitchen S , Malia R G , Triger D R , Greaves M , Preston F E
Published: August 2018

In the UK, rabbit brain thromboplastin has recently replaced human thromboplastin. Since the sensitivity of thromboplastin varies according to species of origin, and the calibration of thromboplastins is based entirely on samples from normal subjects and patients on oral anticoagulants, a separate assessment is required in patients with liver disease. We have compared prothrombin times and specific one stage assays of factors V, VII and X in plasma from 19 patients with establishe < liver disease using rabbit thromboplastin (Manchester reagent, MR) and human thromboplastin (Manchester comparative reagent, MCR). Both materials were kindly provided by the National (UK) Reference Laboratory for Anticoagulant Control. Three separate analyses were performed on the prothrombin time data viz clotting time, prolongation of prothrombin time compared with control and prothrombin ratio. All were significantly longer with MR (p 0.001, paired ‘t’ test) although correlation was goo< (r=0.95 in all instances).

In the assay of factors V, VII and X no significant differences were obtained with the two thromboplastins and correlation was good over a range of abnormality (Ranges for MCR and MR respectively were Factor V:0.31-1.23u/ml and 0.32-1.I6u/ml, r=0.96; Factor VII:0.07-1.22u/ml and 0.07-1.17u/ml, r=0.97; Factor X;0.18-1.Olu/ml and 0.17-1.03u/ml, r=0.96. We conclude that in the investigation of the haemostatic defect associated with liver disease rabbit brain thromboplastin is a suitable alternative to human material.
SUBSTITUTION THERAPY WITH ANTITHROMBIN III: CLINICAL EXPERIENCE WITH DECOMPENSATED LIVER CIRRHOSIS AND HEMORRHAGIC COMPLICATIONS
Authors: Lorenz R , Holweger M , Vogel GE , Classen M
Published: August 2018

In patients with decompensated liver cirrhosis, the coagulation disorder requires therapy only when bleeding complications occur. As therapy involves the risk of triggering a consumption coagulopathy, the discussion here examines the beneficial effect of boosting the inhibitor Potential by supplementing the administration of fresh plasma with substitution of AT III concentrate. To investigate this question, we conducted a retrospective study on the clinical course in 19 patients with decompensated liver cirrhosis, hepatic encephalopathy and bleeding complications.

The following treatment scheme was employed uniformly in all 19 cases: substitution of vitamin K 20 mg/d, heparin 100 - 300 U/h and fresh plaspna 2-4 bags/d. AT III concentrate (3 - 8 × 500 U/d Ky-bemin HS ) was administered additionally in group 1 (n=8), but was omitted in group 2 (n= 11). Both groups were statistically comparable with regard to initial laboratory findings (e.g. bilirubin, group 1: 11.7 ± 3.6 mg/dl; bilirubin, group 2: 10 ± 2.9 mg/dl) and encephalopathy Tcoma stages 1-2), with the exception of the two survivors in group - who had been in a precomatose stage (stages 0-1) and had bilirubin levels of 3 ± 1.5 mg/dl.

A comparison oT both collectives shows a lethality of 62.5 % (n=5) for group 1, and of 81 % (n=9) for group 2. Clinically, the incidence of hemorrhagic complications in group 1 was 61 %, but 100 % in group 2, although laboratory analysis showed no differences in the parameters of systemic coagulation. As regards the other laboratory values, including the transaminases and blood count, there were only differences in the development of the bilirubin values which, in group 1, rose to -3 ± 4 mg/dl only during the terminal phase, but which, in group 2, began to rise continuously from the second day of treatment onwards 2nd reached values of 28 ± 8.6 mg/dl.

It follows that, in patients with decompensated liver cirrhosis and bleeding complications, the administration of AT III concentrate (Ky-bernin HS ) as a supplement to conventional coagulation therapy, increases the survival rate and reduces the incidence of further bleeding. It is, however, not possible tc explain the cause of this effect from the analysis of the laboratory data for the systemic coagulation. Therefore, one may hypothesize that the effect is due to beneficial effect of AT III within microcirculation.
HAEMOSTASIS IN NATIVE WHOLE BLOOD: CLINICAL STUDIES WITH THE HAEMOSTATOMETER
Authors: Kovacs I B , Hutton R A , Kernoff P B A
Published: August 2018

The haemostatometer is a new instrument which allows quantitative assessment of haemostasis by monitoring the pattern of haemostatic plug formation (HPF) which occurs in holes in polyethylene tubing through which unanticoagulated blood is flowing under standard conditions (1). The pattern and speed of blood coagulation, subsequent to HPF is also measured by the instrument. Eight healthy volunteers were tested before and 2hr, 5dy and 12dy after a single 600mg oral dose of aspirin. Maximum prolongation of HPF time occurred at 2hr (1.97 × baseline, p=<0.001) and the effect remained significant (p=<0.01) at 5dy. The pattern of the aspirin-induced effect on HPF was characteristic. The coagulation time was not affected by aspirin. In 4 patients with platelet release defects, the HPF time, but not the clotting time, was significantly prolonged (2.1 × controls, p= <0.01). In 4 patients with von Willebrand’s disease of different severities, platelet-collagen interaction was tested simultaneously with HPF by inserting a length of catgut into the tubing and measuring the time to cessation of blood flow (2).Both impaired HPF and ineffective formation of occlusive platelet thrombus on the catgut were observed. In haemophilia A patients, HPF time as well as clotting time was prolonged in some cases and in these, improvement of platelet function (shortened HPF time) occurred following factor VIII therapy. As diabetes mellitus may be associated with a prethrombotic state, 20 diabetics were tested and shown to have a shortened HPF time.

(1) Gorog P, Kovacs I. Haemostasis, 16, 337-45, 1986. (2) Gorog P, Kakkar W. Amer J Clin Path, 86, 311-16, 1986.
PROTECTIVE ANTITHROMBOTIC ACTION OF THE PREPARATIONS FROM THE LEECHES HIRUDO MED ICINAL IS
Authors: Nikonov G , Baskova I
Published: August 2018

Blood letting effect of the medicinal leeches is provided by antihaemostatic properties of the salivary gland secretion. We have demonstrated that the natural salivary gland secretion inhibits the vascular-platelets haemostasis and the contact stage of the intrinsic mechnism of blood coagulation but has no effect on the activation of extrinsic mechanism (Bui 1.Exp.Biol.Med.USSR 97, 6, 696; 8, 142, 1984). Leech prostaglandins (Dokl.Acad.Nauk USSR, 1987) and inhibitors of plasma kallikrein and Factor XI la are the main anti haemostatic agents of the leech saliva.

The leech saliva does not change the main parameters of blood coagulation of the healthy animals, such as recalcification time, cephalin time, thrombin and prothrombin time 5, 15 and 25 min after intravenous injection. But the platelets aggregation stimulated by thrombin is diminished by 20% (n=30;p 0,02) Recalcification time, cephalin time and platelets aggregation reduced by intravenous injection of human serum is corrected by leech saliva.

As the trigger mechanisms of haemostasis are very much alike the trigger mechanisms of thrombogenes?s, we investigated antithrombotic ability of the leech saliva, extracts of dried leeches and blood of intestinal gut. We used Wessler procedure of throm-bous formation in rats.

The thrombous formation was diminished by 90% compared to control when 0.3 ml of the leech saliva (diluted with saline 1:4) was injected intravenously 2-4 hrs before injection of human serum. Thrombous formation was diminished by 40% when time interval was elongated to 24-28 hrs. Antithrombotic effect does not depend on the antithrombin activity of hirudin. It slightly decreased in case of oral administration and increased after the multiple intravenous injections or oral administration.

Blood from the leech intestinal tract and other preparations from the leeches exhibit less distinct antithrombotic effect than the salivatory gland secretion.
DISTRIBUTION AND IDENTIFICATION OF FIBRINOGEN, FIBRIN AND DEGRADATION PRODUCTS IN ATHEROSCLEROSIS BY MONOCLONAL ANTIBODIES
Authors: Fenglio J , Bini A , Mega-Tejada R , Kudryk B , Kaplan K L
Published: August 2018

Specimens from vascular surgery and from heart transplant recipients were examined. The tissues were stained with the avidin biotin complex-immunoperoxidase technique using specific monoclonal antibodies (MAbs) for fibrinogen and fibrin. MAb I8C6 detects fibrinogen and fibrin I, MAb T2G1 is specific for fibrin II, MAb GC4 recognizes fragments D and D-D and does not cross-react with fibrinogen. Polyclonal antisera for fibrinogen, albumin and IgG were used as controls or as markers of increased vessel wall permeability. Serial sections of each specimen were stained with all the antibodies and the distribution of the different antigens compared. In samples of 4 normal thoracic aortas fibrinogen was present in 3/14 sections from different areas. Fibrin II and degradation products were absent. In 7 fibrous plaques, fibrinogen, fibrin II and fragment D were present, distributed in strands or in focal deposits. In most cases a stellate, patchy pattern of distribution was observed for fibrinogen and fibrin II suggestive of association with vessel wall cells and macrophages. In 7 complicated plaques fibrin II was always associated with fibrinogen, fragment D, albumin and IgG in areas of thrombus and these antigens were also present around cholesterol crystals and calcium deposits. In less severely affected areas some fibrinogen was focally distributed and fragment D was associated with fibrin II in granulation tissue. In three coronaries, fibrinogen and fibrin II were distributed in areas of early or fibrous plaque in which no fragment D was detected. In all the samples albumin and IgG were associated with fibrinogen and fibrin deposits suggesting penetration of plasma proteins into the vessel wall. These results indicate that polymerization and degradation of fibrin might occur not only on the luminal surface, but also within the vessel wall with cellular participation, thus contributing to the evolution of the atherosclerotic lesion. The use of specific monoclonal antibodies has made it possible to distinguish the distribution of fibrinogen and fibrin I, fibrin II and fragments D and D-D in normal and atherosclerotic vessels.
DETERMINATION OF CHOLESTERYL HYDROXYOCTADBCADIENOATES IN VASCULAR TISSUE BY HPLC AND ITS RELEVANCE TO ATHEROSCLEROSIS
Authors: Heiremans J , Claeys M , Herman A G
Published: August 2018

Accumulation of lipids in the intimal arterial layer, and of cholesterol esters in particular, has been recognised as an early and prominent phenomenon in atherogenesis. Several attempts have been made to link putative peroxidation of these lipids in vivo to causal or deteriorating etiological determinants of plaque formation. The occurrence in advanced human atheromata of oxidized derivatives of cholesteryl linoleate -a major polyunsaturated cholesterol ester species in plasma and vessel wall - has been described by Brooks et al. (Atherosclerosis, 1970,13,223) and a positive correlation between the amount of cholesteryl hydroxyoctadecadienoates (CHODES) and the stage of the lesion has also been reported. In addition Funk and Powell (J. Biol. Chem., 1985,260,7481) have found hydroxyoctadecadienoic acids in normal aorta of different species, wich were strikingly increased after alkaline hydrolysis of total lipids, and this in contrast with the arachidonic acid analogs. The aim of this study was to develop a sensitive and practical method for specific assay of CHODES, without resorting to laborious saponification and derivatisation procedures required for gas chromatographic analysis, which could moreover augment the risk for artefacts.

Dog thoracal aorta was homogenised and lipids were extracted using the Folch method with CHCl3/CH30H;2/l containing 0.05mM butylated hydroxytoluene. Fractionation of CHODES from neutral lipids was carried out by thin-layer chromatography. For detection and quantification a high-performance liquid chromatography (HPI/2) assay method was developed, with UV monitoring at 232nm , a wavelength characteristic for conjugated dienes with vicinal hydroxyl function. Reference compounds and the internal standard for HPLC analysis were synthesized from linoleic acid and 10,13,16-docosatrienoic acid, respectively, by preparation of hydroxy fatty acids with soybean lipoxygenase and subsequent esterification to cholesterol esters with pancreas cholesterol esterase. Confirmation of the structural identity was obtained by mass spectrometry. Artefactual formation of CHODES ex vivo was investigated by subjecting radiolabeled cholesteryl linoleate through the analysis procedure. This method allows the specific detection of CHODES in non-atherosclerotic arteries which was hitherto only reported for human advanced atherosclerotic lesions and is proposed as a sensitive and specific probe for prospective survey of lipid peroxidation in atherosclerotic blood vessels.
PERIVASCULAR CAROTID ARTERY INJURY LEAD TO ATHEROSCLEROSIS IN HYPERCHOLESTEROLEMIC RABBITS
Authors: Nishizawa E E , Williams D J
Published: August 2018

We have previously shown that endothelial injury results when clotted blood is placed perivascularly around a rabbit carotid artery. This injury was manifested by loss of endothelial cells and adherence of leukocytes and platelets. When similar injury was induced in hypercholesterolemic rabbits, medial lesions as well as intimal proliferation was observed. We have extended these studies and have found that these lesions contain high concentrations of cholesterol (200-300 mg/gm protein compared to 40-80 mg/gm protein in controls) suggesting lipid infiltration. The uniformity of lipid accumulation along the injured tissue segment, which was measured as intimal thickening of serial sections, suggests that these lesions are not focal and that the injury was initiated by the perivascular blood rather than by mechanical injury. The contralateral non-injured vessels showed no lesions (0-2% of the total intima + media area) and normal cholesterol content. When the serum cholesterol level was decreased from about 1200 mg/dl to 450 mg/dl by use of drugs such as Colestid, the intimal proliferation was 8.9% compared to the untreated controls, which were around 36%. Aspirin, which did not lower serum cholesterol, had no effect on intimal proliferation and arterial cholesterol accumulation. These studies suggest that this model might be useful for evaluating antiatherosclerotic drugs.
AN IMPROVED METHOD FOR COVALENT IMMOBILISATION OF HEPARIN BY END POINT ATTACHMENT
Authors: Larm O , Adolfsson L , Gouda I , Malmberg A , Olsson P , Scholander E
Published: August 2018

When creating a non-thrombogenic surface by immobilisation of heparin, most of the biological activity of heparin as it is expressed in blood should be retained after the coupling procedure. Consequently the chemical methods used in the immobilisation procedure shall be selected so that they do not, infavorably, affect the anti-thrombin (AT) binding site, the charge distribution and charge density of heparin.

To ascertain that the AT-binding sequence is not involved in the coupling procedure, we have developed a method in which heparin is coupled by end point attachment (EPA). Heparin is partially degraded with nitrous acid and fragments with reactive aldehydo functions in the reducing terminal residues are formed. These are coupled to aminated surfaces by reductive amination. The primary amines have been introduced on the substrates in different ways, depending on their hydrophobic or hydrophilic characteristics.

It has been possible to furnish such complex devices as hollow fibre oxygenators, tubing sets and cannulas with the heparin surface. Heparinized oxygenators have successfully been used in vivo and clinically without and/or with limited systemic heparinization.
ANTITHROMBIN III BINDING TO IMMOBILIZED HEPARIN FRAGMENTS AND ITS RELATION TO F XA INHIBITION
Authors: Kodama K , Larm O , Olsson P , Pasehe B , Risenfeldt J , Swedenborg J
Published: August 2018

Covalent end-point attachment of heparin fragments (8 000 daltons) to artitifical materials results as published before in a highly thromboresistant surface. Approximately one out of six bonded fragments carry the antithrombin III (AT) binding sequence. i.e. the high affinity site. With regard to thrombin inhibition the heparin surface resembles the endothelium. The present work deals with the uptake on the immobilized heparin and its significance for F Xa inhibition. The uptake of AT was studied at 0.15 M and 0.35 M NaCl concentration (TRIS buffer, pH 7.4) respectively and determined as disappearance of AT activity in the exposed solutions. Large amounts were adsorbed at 0.15 M and the uptake was both concentration and time dependent. At 0.35 M the uptake was the same at all the tested AT concentrations: 5 pico-moles/square cm. It was deduced that mainly high affinity sites had taken up AT at 0.35 M and that both high and low affinity sites had taken up AT at 0.15 M.

The non-AT-adsorbed heparin surface did not induce inhibition of F Xa (in TRIS buffer solution) after exposure. The surface AT-adsorbed at 0.15 M induced F Xa inhibition with the same rate in several consecutive exposed aliquots. The surface AT-adsorbed at 0.35 M had a lower inhibitory capacity and only the first F Xa aliquot was inhibited at the same rate as on the surface AT-adsorbed at 0.15 M. The inhibition rate for a second aliquot was slowlier due to the facts that AT had been consumed and that the density of AT on high affinity sites had decreased. It is concluded that AT on high affinity sites determines the rate at which F Xa is inhibited whereas the amount of AT on low affinity sites determines the inhibitory capacity by continously providing the high affinity sites with AT. The migration of AT must take place horizontally in the 100-200 A thick surface layer and may mimic events happening on a cellular membrane with binding sites of different classes for a substance.
THE EARLY THROMBOGENICITY OF IMPREGNATED DACRON GRAFTS ASSESSED IN AN ARTIFICIAL CIRCULATION
Authors: Bibby S R , Crow M J , Puri S R , Sheehan S J , Rajah S M , Kester R C
Published: August 2018

The impregnation of knitted Dacron grafts with biodegradable protein removes the need for preclotting at implantation. The effect of such impregnation on the thrombogenic potential of these prostheses is, however, unknown. We have compared the early thrombogenicity of two impregnated knitted Dacron grafts - Hemashield ( collagen-impregnated Dacron, Meadox) and Gelseal (gelatin-impregnated Dacron, Vascutek) -with conventionally preclotted knitted Dacron in an artificial circulation. Fresh, heparinised human blood, containing 111Indium-labelled platelets, was circulated around identical twin circuits of silicone tubing by a Sarns roller pump at 180 ml/min and 120 mmHg. Into each circuit a different 15 cm × 8 mm type of graft material was mounted. Changes in platelet count, platelet aggregation to collagen, plasma haemoglobin and blood radioactivity were recorded and after 60 minutes of perfusion each graft was sectioned and counted for radioactivity prior to scanning electron microscopy (SEM) of the luminal surface. The mean graft radioactivity divided by the mean blood radioactivity yields a Graft Activity Index (GAI) allowing comparison of platelet deposition and thus thrombogenicity.

RESULTS: (mean ± s.e.m.) 8 examples of each graft

SEM confirmed these findings with preclotted Dacron having the highest platelet deposition. Both impregnated grafts produced significant early haemolysis within 4 minutes of blood contact. Our findings indicate that the early thrombogenicity of these impregnated grafts is significantly less than conventionally preclotted Dacron, (p< 0.01, Wilcoxon signed rank test), despite the early haemolytic phenomenon and that Hemashield grafts are less thrombogenic than Gelseal grafts. (p<0.05, Wilcoxon signed rank test)
EVIDENCE FOR AN INCREASED FIBRONECTIN SYNTHESIS IN VASCULAR ENDOTHELIUM OF DIABETIC SUBJECTS
Authors: Musso R , Longo A , Morrone M L , Cacciola R R , Lombardo A , Giustolisi R
Published: August 2018

Increased plasma levels of Fibronectin (Fn),a well known adesive glycoprotein synthesized in vessel endothelial cells, have been reported in diabetes mellitus (DM). Previously, we provided evidence that in type II DM an elevated storage of Fn is present in endothelial cells. We here report that in diabetic subjects an abnormal synthesis of Fn in endothelial cells could also occur. To verify this hypothesis, in 15 patients affected by type II DM, age ranging 36-59, of both sex, without overt clinical vascular complications and in glycometabolic compensation (Hb Alc 8.9 ± 1.5) we evaluated before and after venostasis repeated at several times 30, 60, 90,180 and 210 min the Fn plasma levels. Five healthy volunteers, age and sex comparaf-h ble, were utilized as normal controls. The venostasis were performed at forearm pressure of 10 mmHg over diastolic x 20 min and blood samples were collected from the same vein at the intervals above indicated. Plasma Fn was evaluated by ELISA immuno-enzymatic tecnique using a commercial kit (Biochemia, Milan). The diabetic patients showed after the first venostasis a significant (p<0.001) increase of Fn (317 ± 103μg/ml) versus the baseline values (225±79 μg/ml)while normal controls did not (before 103 ± 37, after 139±61). Such an increase was also seen in EM after the second venostasis ( 298 ±91 μg/ml, vs 128±58 in controls), whereas at third venostasis plasma Fn levels retoumed to the values comparable to the basal ones both in diabetics (245 ±. 88 μg/ml) and in controls (93±41 μg/ml). After 90 min pause by performing the fourth venostasis we observed in diabetics a further increase pf Fn (298±131μg/ml) which reached:again the values noted after the first. No change, on the contrary,was found in the normal group (95±21). In the last venostasis,carried out 30min from the fourth, the plasna Fn lasted significantly (p<0.001.) increased in diabetics (281±107 μg/ml) respect to normal controls (102±19 μg/ml).

Our data, therefore, would suggest that in vascular endothelium cf type II DM an increased synthesis of Fn occurs as well.
THROMBOSIS RISK FACTORS IN CARDIOVASCULAR SURGERY IN CHILDREN AND ADULTS
Authors: Philapitsch A , Ponov S , Kirchhoff P G , Urban E , Anderle K , Hrdinka R
Published: August 2018

Antithrombin III (AT-III) and protein C (PC) deficiencies are knoi/n to be associated v/ith a major risk of thrombosis. Before, during and after cardiovascular surgery (CS) AT-III end PC were investigated in plasma samples obtained within the framework of a randomised Cl-esterase inhibitor (Cl-INH)-c.pro-tinin-placebo study in adults undergoing extracornoreel circulation (ECC), and children subjected to ECC and treated with aprotinin. Determination of AT-III and PC activity gave the following results:

AT-III: Preoperative values in adults (n = 25) and children (r: = 11) were normal amounting to a median of 92 % and 10C %, res; actively. In adults a steady decrease in AT-III without any difference between the 3 groups occurred durinc ECC rntil the 1st postoperative (po) day where AT-III had faller: to CC % (median). In children the same decrease was observed duri;r ECC, however, after termination of ECC AT-III increased until normal on the 1st day po (median = 85 %) and this difference between adults and children is significant at a p of 0.019.

Protein C: Median preoperative values in adults (n = 45) were 111 %, while in children (n = 11) only 48 % were found. During and after surgery in children there was no change in PC, while significant differences were found between the 3 adult groups. In the placebo group and the aprotinin group PC fell to 69 % (median) and 86 % (median), respectively, on the 1st day po. However, in the group receiving CI-INH Concentrate (Immeno) PC increased up to 136 % and only after discontinuation of treat; a-r.t decreased to 92 % (median). The significant rise in PC ir. the CI-INH group is explained by the content of PC in the CI-IMII Concentrate. These findings are indicative of a significant difference in the behaviour of AT-III and PC in children and adults, and suggest that the administration of CI-INH Concentrate may reduce the risk of thrombosis associated with ECC.
RATIONAL FOR A DYNAMIC TEST TO INVESTIGATE POTENTIAL VASCULAR FIBRINOLYSIS IN PATIENTS AT RISK OF PERSISTENT THROMBOSIS
Authors: Sultan Y , Harris A , Strauch G , De Lauture D , Venot A
Published: August 2018

Defense mechanism against intravascular clot formation is dependant upon the release of free tissue plasminogen activator (t-PA) from the vascular wall. To investigate this function a dynamic test is necessary to differenciate patients at risk of persistant thrombosis from patients who possess potential capacity to dissolve intravascular clots. In the present study, three different routes of administration of DDAVP and venous occlusion (VO) were applied to 9 healthy young volunteers in order to determine the best stimulus and the best test to assess individual capacity of releasing free t-PA in circulation. DDAVP was intravenously administered at a dose of 0,4 pg/kg body weight, and intranasally at a dose of 300 pg by two different preparations drops and spray. The same volunteers were also submitted to VO on 2 occasions after 1 H and after 10 mn of rest. In blood samples collected before and after the stimulation, t-PA activity and antigen, t-PA inhibitor (PAI) and euglobulin lysis time (ELT) were measured. Only one stimulus (IV DDAVP) and one test (t-PA activity in euglobulins) identified 100 per cent of normal subjects as capable of developing increased fibrinolytic activity. All other stimuli and especially VO pointed out absence of fibrinolytic response in several normal subjects, for exemple t-PA activity in euglobulins was found enhanced in all 9 subjects after IV DDAVP but in only five after VO. In addition, some tests such as ELT were found to be not sensitive enough to detect t-PA activity release. This study also showed that after DDAVP injection, PAI abruptly decreased in correlation with the release of t-PA activity. However t-PA activity can reach high levels in blood although PAI is still measurable suggesting that after release t-PA activity is not immediatly inhibited by PAI and that they can both coexist. These results demonstrate that the choice of the stimulus and the test to measure fibrinolytic activity have to be carefully determined to identify patients at risk of persistent thrombosis.