bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF TRIFLUOPERAZINE (TFP) ON HUMAN PLATELET MEMBRANE
Authors: Wang C T , Lee J Y , Chen J C , Shiao Y J , Tsai W J
Published: August 2018

TFP is a lipophilic antipsychotic drug. The drug will first encounter with cell membrane when adding it into a cell suspension. The effect of TFP on plasma membrane of the gel-filtered human platelet was investigated by : 1) scanning electron microscopy (SEM); 2) measuring theleakiness of marker enzymes and compound; 3) estimating its solubility in membrane. The cells were suspended in the modified Tyrode's buffer containing 0.1% dextrose, 0.2% of bovine serum albumin and without calcium. The SEM study showed that platelet changed shape from disc to ellipsoid in 10 μM TFP.,Increasingthe TFP concentration from 20 μM to 50 μM resulted in changing thecell from ellipsoid to sphere with a wavy surface. The drug did not cause any significant change in the cell volume. TFPof 70 μM caused platelet becoming a round ball shape with a spongy-like cell surface. 100 μM TFP caused more than 90% of cells to lyse and to agglutinate with each other. The time courseof morphological change of the TFP-affected platelets showed that the cellsswelled into irregular shape within 2 min. Apparent leakiness of serotonin was observed at 20 μM TFP, while the leakages of both lactate dehydrogenase and acid hydrolase were found at 40 μM TFP. The TFP uptake study showed that platelet was permeable to TFP by simple diffusion. The partition coefficient of TFP in platelet membrane was estimated to be 1 x 104. These results indicate that TFP molecules are solubilized in membrane. The extent in perturbation of the membrane structure depends on concentration of the drug used. (This research was supported by a grant from the National Science Council of the Republic of China.)
STAI (Studio Ticlopidina Angina Instabile) PROJECT. TICLOPIDINE -IN UNSTABLE ANGINA
Authors: Violi F , Cimminiello C , Chierichetti S , Scatigna M , Rizzon P , Balsano F
Published: August 2018

The treatment of patients suffering from unstable angina (UA) with antiplatelet drugs is a therapeutic approach that provided interesting results.

Patients given aspirin, that inhibits cyclooxigenase pathway (CP) showed a significant reduction of cardiovascularevents.

Quite surprisingly sulfinpirazone, that possesses a mechanism of action similar to aspirin, did not influence cardiovascular complications of UA patients.

To further investigate the role of platelets in UA patients, we planned to study if ticlopidine (T), that inhibits platelet function by blocking fibrinogen binding to platelets, influences theclinical course of UA.

The study will include 1200 randomised patients given conventional therapy with or without T (500 mg/daily).

Patients enrolled have to show one ofthe following clinical pictures:
1) angina at rest;
2) "crescendo angina";
3) new onset angina.

Clinical symptoms should be present within 30 days. The follow-up will last6 months.

Primary end-point of the study is the incidence of fatal and non-fatal myocardial infarction and of vascular death.

Apart from the possible influence of T in the natural course of UA, the study will offer the opportunity to find and incidence pattern of UA cardiovascular complications in Italy.
ASPIRIN MODIFIES RED BLOOD CELL BEHAVIOUR (RBC) IN THE PLATELET-RBC INTERACTION
Authors: Santos M T , Aznar J , Valles J , Perez-Reguejo J L
Published: August 2018

RBC stimulate the initial stages of platelet activation by collagen as evaluated by the BASIC wave (Perez-Requejo et al. Thromb Haemostas 54:799 1985). In order to get some insight into the mechanisms of platelet-RBC interactions, a BASIC wave was induced by lug/ml of collagen after mixing "in vitro" platelets and RBC obtained both before and two hours after a single dose of 500 mg of ASA from normal subjects. The TXB2 formed was also evaluated. The results show (Table) that non aspirinized RBC (non-ASA-RBC) increase the BASIC wave intensity of aspirinized platelets (ASA-PRP) by a cyclooxygenase-independent pathway since no increase in TXB2 was observed (Exp 1), while both non-ASA-RBC (Exp 2) and ASA-RBC (Exp 3) activate non-ASA platelets with theparticipation of the cyclooxygenase system, since an increase in TXA2 was found.A comparison of the effect of non-ASA-RBC (Exp 1) and ASA-RBC (Exp 4) on aspirinized platelets shows that ASA modifies the RBC behaviour associated with estimulation of platelets by a cyclooxygenase-independent pathway. This effect of ASA on RBC is nottransient and lasts at least 48 hours after ASA ingestion. In addition, when asmall proportion of nonASA platelets (10%) is mixed with aspirinized platelets(90%) and ASA-RBC - a situation that can be encountered "in vivo" inthe hours following ASA ingestion - the intensity of the BASIC wave is 89% of that obtained when all the platelets are non aspirinized. This RBC effect on the mixtureof ASA and nonASA platelets, may help explain the sometimes contradictory effect of ASA as an antithrombotic agent.
TREATMENT OF PERIPHERAL VASCULAR DISEASE WITH ILOPROST (ZK36374)
Authors: Catalano M , Belletti S , Coazzoli E , Gherardi E , Lopriore F , Russo U , Libretti A
Published: August 2018

The action of a stable analogue of prostacyclin, Iloprost, was studied in 18 male in-patients aged 51-69 yr (mean 61±7) with peripheral vascular disease Fontaine stage lib and III who gave informed consent. Entry criteria were Fontaine stage III or II with free interval at treadmill test ≺ 100 m. (4 km/h, without slope), ankle/arm arterial pressure index (API)≺0.7 at rest. Patients with arterial hypertension, diabetes, myocardial infarction in the previous 6 mo, heart failure, thrombocytopenia, hemorrhagic diathesis, or kidney or liver failure were excluded. The patients underwent 3 weeks' treatment with 6-h infusion/day of placebo for week 1, Iloprost 1 ng/kg/min for week 2, and Iloprost 2 ng/kg/min for week 3. Before treatment, at the end of each treatment week, and 15, 30 and 60 days after the end of treatment we evaluated: absolute pain-free interval(APFI), relative pain-free interval (RPFI), and API. Platelet aggregation by ADP and collagen and plasma BTG and PF levels were also determined, and complete blood tests and ECG performed. All the patients showed a progressive but variable increase in RPFI and APFI at 15, 30 and 60 days compared with the valuesat baseline and the end of the week on placebo (basal vs 15, 30 and 60 days, p≺0.01 for both parameters, AN0VA BR and Tukey's test). The % variations of APFI compared with baseline were 58.7, 62 and 95.5% at 15, 30 and 60 days. No other significant variations were observed. The results obtained seem to indicate that the drug is effective since there was an increase in the pain-free interval starting from 15 days after treatment suspension which persisted at 60 days. A first hypothesis is that this could be the result of increased flow due to improved collateral circulation by a mechanism not influenced by the platelet parameters considered that merits further study.
ASPIRIN AND THE KIDNEY IN PATIENTS WITH CEREBRAL ISCHEMIA
Authors: Monreal M , Lafoz E , Foz M , Monasterio J
Published: August 2018

The acceptance of aspirin therapy for prevention of cerebral ischemia is based onpositive results of several large clinicaltrials, and the usual dose is 1000-1500 mg/day. Several recent reports emphasize the adverse effects of aspirin and other nonsteroidal anti-inflamatory agents on renal function. We examined wether two extreme doses of aspirin (60 mg vs 1200 mg/day) could alter renal function in patients recently admitted to hospital with cerebral ischemia. We studied 33 patients with cerebralischemia and no history of ingestion of aspirin nor other drugs two weeks prior to admission. During the first 5 days all patients received a 50 mEq sodium diet and no drugs, while during the second 5 days (trial) the patients were randomly assigned (double blind) to placebo, aspirin 20 mg or aspirin 400 mg, 3 times daily, with meals.

Overall, body weight increased by 650 gin patients taking 1400 mg/day of aspirin (p≺0,01), but not in patients taking 60 mg/day. Also increases in systolic and diastolic blood pressure did not reach significant differences. While waiting morereports, aspirin at doses near 1000 mg should be administered cautiously in sodium restricted patients with cerebral ischemia.Acute water retention may be specially troublesome.
TANDEM PURIFICATION OF TISSUE PLASMINOGEN ACTIVATOR BY METAL CHELATE AND AFFINITY CHROMATOGRAPHY
Authors: Electricwala A , Atkinson T
Published: August 2018

A tandem purification procedure was developed by a combination of metal chelate and affinity chromatography. The conditioned medium from different cell lines producing tissue plasminogen activator was first chromatographed on a zinc chelate-agarose column equilibrated with low ionic strength buffer. After thorough washing, the column was connected to a lysine-agarose column, previously equilibrated with the same buffer. Tissue plasminogen activator was eluted from the zinc chelate column by a gradient of imidazole and the effluent was allowed to flow through lysine-agarose matrix. The two columns were disconnected and after thorough washing, the bound enzyme from lysine-agarose column was eluted with a linear gradient of potassium thiocyanate in the equilibration buffer. This method resulted in a purification factor which varied between 40 to 110 fold. The purity of the isolated enzyme was assessed by sodium dodecyl sulphate-gel electrophoresis and fibrin zymography. The chromatographic procedure described provides a novel method for the rapid purification of tissue plasminogen activator to a high degree of purity.
INHIBITORS OF FIBRINOLYSIS IN THE EUGLOBULIN FRACTION OF SNAKE PLASMA (Bothrops j araraca)
Authors: Kelen E M A , Chudzinski A M , Goncalves L R C , Rothschild Z
Published: August 2018

Blood of most Reptilia has a naturally occurring circulating anticoagulant which inhibits thrombin activity. Besides, the intrinsic thromboplastin formation is deficient in snakes, and contact phase factors were not detected when measured on heterologous substrates. No records on fibrinolytic activity were found. The fibrinolytic activity of the euglobulin fraction of snake plasma (B, jararaca) in standard conditions is here reported. Nembutal anesthetized male and female animals were used for blood collection from the aorta artery and/or a vein after surgical exposure. Euglobulin fractions (EF) of plasma were obtained by dilution (1:10) and isoelectric precipitation (5.9). Activity was tested on human fibrin plates, immediately after preparation (EF1), after 24 hours at 4°C (EF2), and in both cases, in the presence of 2.1 m>: flufenamil-beta-alanine (Flu-beta-Ala)(EF3, EF4). Euglobulin clot lysis time (ECLT) was also determined. Fibrinolytic activity on the heterologous fibrin plate was obtained with EF1 of male plasma but the range of variation was high (23 to 100 mm2). Activity increased from EF1 to EF4 but never reached human EF values. They were much lower in female EF1 with about 70% negative results. On the other hand, ECLT of EF3 from both male and female plasma was markedly shortened when compared to the long and extremely variable results obtained with EF1. Also, snake EF1 prolonged the ECLT of human EF1. Results suggest that snake plasma contains high levels of inhibitors of fibrinolysis that are coprecipitated with the EF, and this is more intense with female plasma. The nature of such inhibitors has to be investigated.
FIBRINOPEPTIDE BB 15-42 AND FIBRINOPEPTIDE A IN ATHEROSCLEROTIC DISEASE
Authors: Marongiu F , Mulas G , Mameli G , Acca M , Tronci M B , Vannini M L , Sanna M P , Cambuli A B , Balestrieri A
Published: August 2018

The present study is a preliminary approach to detect both blood coagulation and fibrinolysis activation by employing RIA for fibrinopeptide A (FPA) (Mallinckrodt) and BB 15-42 (IMCO and SORIN Biomedica) in 30 patients with atherosclerotic disease.The patients (20 men and 10 women, mean age 57.4 ± 11.9 years) were affected by myocardial infarction (n=12), stroke (n=5), transitory ischemic attacks (n=7) and unstable angina (n=8).Because of the non normal distribution of FPA as well as of BB 15-42, results are expressed as median and range.Mann-Whitney test has been used for statistical analysis.FPA levels in patients (3.5, 1.1-9.5 ng/ml) were significantly higher than those of the controls (2.6, 0.5-4.9 ng/ml) (p<0.05).BB 15-42 levels in patients (17.9, 4.7-73.1 ng/ml) were significantly higher than those of the controls (10.5, 5.1-15.4 ng/ml) (p < 0.01).There was no relationship between FPA and BB 15-42.Patients with BB 15-42 15 ng/ml showed similar FPA levels similar to those with BB 15-42 15 ng/ml.Our data indicate that plasmin action is not related to thrombin activity .Therefore the high BB 15-42 levels may be due in atherosclerotic disease to a continous plasmin action on the fibrin deposited on atherosclerotic plaques.In patients with high FPA levels fibrin could have been produced before the increases in thrombin activity.
A MONOCLONAL BASED ELISA FOR HUMAN u-PA QUANTIFICATION
Authors: Camacho M , Fabra A , Carretero F , Borrell M , Millet I , Rutllant M L
Published: August 2018

An ELISA has been developped for quantifiing the anti gen levels of u-PA present in human plasma, tissue and cell extracts, conditioned medium and others biological fluids.

The assay was set up using PVC plates coated with rabbit anti u-PA IgG and a monoclonal antibody against human u-PA as second antibody (UKM23 obtained in our laboratory as previously described).Detection was performed with a rabbit anti-mouse IgG conjugated with horseradish peroxidase.

By immunoblotting technique the monoclonal antibody used UKM23 , recognizes all human molecular weight spe cies and an additional band of 81 KD in human plasma. Also recognizes the u-PA present in conditioned medium from HT-1080 cell line.

The detection limit of ELISA assay is 0,1 ng of total u-PA.The first assay in human plasma from healty volun ters, shows u-PA levels of 4,39 ± 0,94 ng/ml.

This study was supported by grants from the CAICYTn9 1258/81 and 3628/86.
BLEEDING TIME IN NORMAL SUBJECTS: ITS RELATIONSHIP WITH SEX, AGE, BLOOD GROUP, HEMATOCRIT, PLATELET COUNT AND PLASMA VON WILLEBRAND FACTOR LEVEL
Authors: Rodeghiero F , Castaman G , Di Bona E , Ruggeri M
Published: August 2018

Bleeding time (BT) is the most important test for in "vivo" Vevaluation of primary hemostasis. Several physiological parameters namely sex, age, blood group, hematocrit, platelet count and von Willebrand factor level could exert a significant influence

In this study, the relationships between BT (Simplate II,General Diagnostics)and these physiological parameters havebeen examined in 58 subjects aging 17-71 (32 males and 26 females; 26 of 0 and 32 of non-0 group). In all the subjects bleedingdiathesis was excluded by interview. They were not taking anvmedicament for at least 10 days and showed normal platelet aggregation by ADP and Arachidonate

Mean BT value (seconds) was 318± 65 (range 195-A95)Statistical analysis failed to show any significant difference realated to sex and blood group. There was no significant relationship with hematocrit (0.01), platelet count (−0.2A), age (−0.28) and von Willebrand factor level, mesured as ristocetin cofactor (−0.2A). In particular, our data indicate that higher von Willebrand factor levels found in non-0 group in comparison with O-group (113.3 vs 83.5, P < 0:001) do not exert any apparent influence on bleeding time
TREATMENT OF EXPERIMENTAL VENOUS STASIS MODEL IN RATS BY HEPARIN AND A VERY LOW MOLECULAR WEIGHT HEPARIN FRAGMENT. RELATIONSHIP TO PLASMATIC HEPARIN ACTIVITY
Authors: Doutremepuich C , de Sèze O , Castrioto T , Peirera F , Doutremepuich F , Toulemonde F
Published: August 2018

In this work we investigated the possible relationship between plasmatic activity and antithrombotic activity of a Low Molecular Weight Heparin Fragment (CY222, Choay-Paris) compared with Heparin (Hep). A randomized administration of both test drugs was carried out on 198 rats receiving 4 different dosages (4,2,1 or 0.5 mg/Kg b.w.) or a placebo solution (normal saline). A ligature of the inferior vena cava was performed on rats at T = OH and test drugs were administered subcutaneously at T - 2H. Blood and thrombus samples were taken at T = 6H. For all the tests the Heparin level was computed from a standard curve made up of known amounts of the 3 rd STANDARD HEPARIN (W.H.O.).

The statistical study between plasmatic and antithrombotic activities was conducted in 2 steps:
1°) search for linear statistical correlation (correlation factor R, independence test T)For Hep: Thrombin Clotting Time: R = −0.26, T = 0.38, p<0.01; APTT: R = −0.28, T = −2.56, p<0.01; Anti-Xa (chromogenic method CBS 31.39):R = 0.48, T = −4.70, p<0.01; Anti-Xa (Hepaclot, Stago):R = −0.35 T = −3.24, p<0.01; Anti-Xa (Heptest, Haemachem, INC): R = −0.36, T = −3.21, p<0.01; Anti-IIa (chromogenic method CBS 34.47): R = −0.32, T = -2.84, pCO.Ol;
For CY222: Anti-Xa (chromogenic method): R = −0.23, T = −1.80, p=0.07; Anti-IIa (chromogenic method): R = −0.26, T = −2.07, p<0.05; 2°) a multivariate regression between thrombus weight (mg) and the plasmatic activity of both the test drugs:
For Hep Anti-Xa (chromogenic method): F = 14.56
For CY222 Anti-IIa (chromogenic method): F = 14.40 and Anti-Xa (chromogenic method): F = 5.96.

In conclusion, we observe a statistical correlation between Anti-IIa activity and thrombus regression. These parameters may use in human Low Molecular Weight Heparin therapy.
THE EFFECT OF HEPARIN AND OP/LMWH ON THE RELEASE OF PLASMINOGEN ACTIVATOR IN PERFUSED RAT HIND LEGS
Authors: Barbanti M , Mastacchi -Alfa Ricerche R
Published: August 2018

The influence of conventional heparin (H) and a new low mole cular weight heparin OP/LMWH (1) on the release of plasminogen ~ activator was studied in the isolated perfused rat hind legs, according to the method described by Emeis (2).In a first series of experiments the conventional heparin was tested at the concentration of 10-25-50 Ul/ml of perfusate and OP/LMWH at the corresponding concentration on a weight basis. Neither products, in these experimental conditions, produced a significant release of plasminogen activator. For this reason a second set of experiments was carried out pretreating the animals with both heparins (10 mg/kg b.w.by intravenous route), 10 min. before starting the perfusion, in order to evaluate the possible effect in more physiological conditions. H induced a significant release of plasminogen activator (up to 0.3-0.4 TPA Unit/ml)from 30 min. after treatment; a similar effect was observed in 70% of the experiments after OP/LMWH treatment.
In conclusion :
1) The heparins do not affect the fibrinolytic activity of blood vessels in an isolated system
2)The profibrinolytic activity of the heparins, observed in the 2nd set of the experiments, suggest thatan interaction with blood and endothelial componentsis necessary for its appea ranee
3) These results are in accordance with our previous results, regarding ex vivo experiments (3).
1)G.Andriuoli et al. Haemostasis 15:324-30, 1985
2)J.J.Emeis Thromb.Res. 30:195-203, 1983
3)M.Barbanti et al. Thromb.Res.Suppl. VI:87, 1986
THE INFLUENCE ON EXPERIMENTAL THROMBOSIS AND HAEMOSTASIS BY LOW MOLECULAR WEIGHT HEPARIN IN COMBINATION WITH DIHYDROERGOTAMINE
Authors: Berqqvist David
Published: August 2018

The influence of low molecular weight heparin (Mw7600) in combination with dihydroergotamine (DHE) onthrombus formation and primary haemostasis was investigated in rabbit models. The jugular veins were used, thrombosis being induced by a combination of endothelial damage (ethoxysclerol) and flow reduction (standardized narrowing of the vein). Haemostatig plug formation was studied by transecting isolated microvessels in the mesentery. Conventional heparin in the dose of 60 units anti Xa activity/kg b.w. effectively prevented thrombus formation but the same dose of a low molecular weight fragment only gave a marginal decrease of the frequency of thrombosis (from79 to 57%). Doubling the dose of the heparin fragment totally abolished thrombus formation as did thecombination of 60 units with DHE.With DHE it was also possible to diminish the low molecular weight heparin dose to 30 units with a good prophylactic effect(7 ?6).There was a small but significant increaseof haemostatic plug formation time in all treatment groups except the one with low molecular weight heparinfragment 30 units anti Xa activity combined withDHE.Thus, by combining low molecular weight heparin withDHE it is possible to prevent thrombus formation without influencing primary haemostasis in rabbits.
THE INFLUENCE OF SURGERY ON PLASMINOGEN ACTIVATOR INHIBITOR
Authors: Neerstrand H , Hedner U , Lützen O , Hauch O , Jørgensen L Nannestad , Ner-strøm H , Kølle T R , Wille-Jørqensen P
Published: August 2018

In a previous study we have shown that plasminogen activator inhibitor (PAI) decreased in normal healthy volunteers during the day from 6.3±3.1 IU/ml (X±ISD) at 7.15 a.m. to 2.8±2.3 IU/ml at 3 p.m.

The aim of the present study was to investigate the effect of major elective abdominal surgery on PAI. Eight patients received 2,500 Xal units of low molecular weight heparin (LogiparinTM) (Gr.l) and 7 patients received 3,500 Xal units of Logiparin (Gr.2). The PAI activity was measured amidolytically according to Chmielewska et al 1983.

The plasma level of PAI (IU/ml) was (X±1SD):

We found that PAI did not decrease during the day of surgery but the PAI level was significantly higher on the morning after surgery than the previous morning (p ‹ 0.05). The 5th postoperative day the PAI level had returned to pre-operative values in the morning, but did not decrease during the day as seen in normal volunteers. The PAI levels were not influenced by the different doses of heparin.

Thus PAI was found to increase postoperatively and the normal decrease in PAI during the day seems to be abolished for at least five days after surgery.
PAF ANTAGONISM AND THE RESPONSE TO ALLERGEN
Authors: SANJAR S , SMITH D , MORLEY J , MAZZONI L , TAPPARELLI C
Published: August 2018

Intravenous infusion of platelet activating factor (PAF) causes platelets to aggregate and accumulate within the lung. A similar effect is observed when allergen is injected into sensitised animals. Since PAF is released in allergic reactions, it might be considered to be a mediator of this phenomenon. Intrathoracic accumulation of 111-Indium labelled platelets was detected by use of collimated sodium iodide crystal detectors as a part of an automated isotope monitoring system (AIMS 8000, Mumed ltd.). Intravenous infusion of PAF (600 ng/kg/h) caused progressive increase of the intrathoracic platelet content (TPC) (59%). Infusion of small doses of allergen (BGG, 300 ug/kg/h) produced comparable increase of TPC, whether animals were sensitised actively (1 mg/kg BGG+FCA i.p. and boosted two weeks later) (30%) or passively (i.v. injection of 0.25 ml anti-BGG serum) (53%) or received intravenous injections of preformed immune complexes. At a dose of 2 mg/kg/h, ginkgolide B (−5%) or kadsuranone (−1%) fully inhibited increased TPC in response to PAF. However, at higher doses (6 mg/kg/h) ginkgolide B did not diminish TPC in animals that were actively (33%) or passively (60%) sensitised, nor did kadsuranone (6 mg/kg/h) diminish the response in passively sensitised animals (42%) compared to vehicle animals (43%). These observations can be extended to acute bronchospasm and airway hyperreactivity which are secondary to platelet activation in these animals. It can be concluded that PAF formation appears to be a minor determinant of the acute response to allergen in the guinea-pig.
HAEMOSTATIC PARAMETERS IN VARIOUS ETHNIC GROUPS IN SAUDI ARABIA
Authors: Gader A M A , Bahakim H , Malaika S , Jabbar F A
Published: August 2018

Geographical and racial differences in the incidence of thrcmbo-embolisn could be related to basic dissimilaritiesin the haemostatic system in different ethnic groups. However reliable comparative population studies in haemostatic parameters is lacking. The large expatriate ccmnunity in Saudi Arabia offers such a chance.

Subjects tested were all healthy blood donors (aged 20-50 years) and were classified on the basis of ethnic origininto three categories (1) Arabs n=750, (2) Westerns (Americans and Europeans) n=400, and (3) S.E. Asians (Filipinos) n=570. The measurements done included PT, PTT, TT, Reptilase time, Plasma fibrinogen, AT III, Plasminogen, F.VIII:C, FX, α-2 Antiplasmin and Platelet aggregation in response to ADP (20.0, 2.0, 1.0, 0.5 & 0.25 uM), Collagen, Arachidonic acid, Adrenaline and Ristocetin (1.5, 1.2 & 1.0 mg/ml).

There were no significant ethnic differences in the measured plasmatic clotting tests. This contrasts the finding of many smaller studies. Besides no significant ethnic differences were noted in platelet aggregation response to high doses of ADP (20 uM) or Ristocetin (1.5 mg/ml) and to Collagen. However, 45% of the S.E. Asians displayed abnormally inhibited responses to Adrenaline when compared to Arabs (34%) and Westerns (35.2%). Asians also displayed more inhibited responses to lower doses of ADP (2.0 & 1.0 uM) . On the other hand, S.E. Asians showed the lowest incidence of inhibited Arachidonic acid responses (9%) when compared to Arabs (24%) and Westerns (26%) . Similar racial differences were noted in response to low doses of Ristocetin (1.2 & 1.0 mg%) where Arabs and Asians showed high incidence of abnormally reduced responses (26-28%) when compared to Westerns (15%). No evidence of enhanced aggregation could be detected in Westerns. Changes of climate and/or dietary habits could be important factors influencing the haemostatic system in such a way that reduces ethnic dissimilarities.
EFFECTS OF BLOOD CELLS ON PLATELET AGGREGATION BY IMPEDANCE METHOD
Authors: Mannucci L , Redaelli R , Tremoll E
Published: August 2018

To evaluate the effects of blood cells on the response of platelets to aggregating agents using whole blood impedance aggregometer, studies were carried out on whole blood (WB) of normal subjects and of patients with: polycythemia vera (PV), iatrogenic anemia (IA), primary thrombocytosis (PT), idiopathic thrombotic purpura (ITP), myeloid chronic leukemia (MCL), iatrogenic leukopenia (IL). The in vitro effects of red blood cells (RBC) and of white blood cells (WBC) on platelet rich plasma (PRP) aggregation were also evaluated. WB, PRP, WBC and RBC were prepared by conventional methods. Aggregation was performed using the impedance aggregometer (mod. 540, Chrono Log Corp). In normal subjects the concentration of collagen giving 50 % aggregation (AC50 ) found in PRP did not differ from that of WB, indicating that hematocrit values within the normal range did not appreciably affect platelet aggregation. The results obtained in WB of patients are summarized in the table: In vitro data showed that aggregation in prp in wb of normal subjects was related to the number of platelets present in the sample. RBC added to PRP significant reduced aggregation only when the RBC number was greater than 4.101 cells. No effect of WBC on collagen induced aggregation of PRP was observed, whereas significant inhibition was detected after ADP. It is concluded that the aggregation evaluated in WB with impedance method is dependent on the platelet number. Also, in vitro data and studies in WB of patients indicate that aggregation is significantly affected by the presence of cells other than platelets only in conditions of changes of the ratio between platelets and leukocytes and/or red cells.
SUBCELLULAR LOCALIZATION OF HUMAN PLATELET LIPOXYGENASE ACTIVITY: COMPARISON BETWEEN NORMAL AND LIPOXYGENASE-DEFICIENT PLATELETS
Authors: Okuma M , Kanaji K , Ushikubi F , Uchino H
Published: August 2018

Lipoxygenase activities were estimated in platelet subcellular fractions as well as in intact platelets obtained from normal subjects and patients with deficient platelet lipoxygenase activities (<mean - 2SD of normal activities). From a washed platelet suspension (intact platelets), subcellular fractions including 12,000 x g supernatant of sonicated platelets (F-I), 105,000 x g supernatant (cytosol, F-II) and sediment (microsomal fraction, F-III) of F-I were prepared by differential centrifugation at 4°C. The enzyme activity was studied by the determination of 12-hy-droxyeicosatetraenoic acid (HETE; ng) produced by the reaction of 100μM arachidonic acid with 108 platelets or the subcellular fraction derived from them at pH 7.4 for 5 min at 37°C in the presence or absence of 2.5 mM CaCl2 and/or 2 mM ATP by the use of reversed-phase high-performance liquid chromatography. In experiments with subcellular fractions, reduced glutathione was added to the reaction mixture. In normal subjects, HETE production by intact platelets, F-I, F-II and F-III was 1,162.4±203.3, 1,029.7±403.8, 368.8±175.8 and 194.4±73.4 (M±SD, n=9), respectively, and was not significantly affected by the addition of CaCl2 and/or ATP. HETE produced by 12,000 x g sediment of sonicated platelets was negligible (<1 % of the product by intact platelets). One of the 7 patients showed no detectable lipoxygenase activity both in intact platelets and in any subcellular fractions, while, the other 6 patients showed reduced lipoxygenase activities in all subcellular fractions as well as in intact platelets: HETE produced by intact platelets, F-I, F-II and F-III was 78.8± 112.3, 59.1± 36.3, 37.0± 18.9 and 17.7±15.8 (n=6), respectively. The addition of CaCl2 significantly increased HETE production only by the patient’s F-I (p< 0.02),while ATP showed no significant effect in any experiments.

Thus, it was shown that lipoxygenaseactivities were not fully exhibited in intact platelets with the deficient enzyme activities and that F-I could produce more HETE than intact platelets especially in the presence of CaCl2 only in the case of such patient’s platelets.
EFFECTS OF HUMAN ATRIAL NATRIURETIC PEPTIDES ON SECRETION REACTION IN HUMAN PLATELETS
Authors: Tanable A , Yatomi Y , Ohashi T , Oka H , Kariya T , Kume S
Published: August 2018

Human atrial natriuretic peptide (h-ANP) has vasodilating and natriuretic properties, and inhibits smooth muscle contraction, renal renin secretion and adrenal aldosterone release. Although Schiffrin has reported that human platelets have receptors for ANP, its effects in platelets are not established in vivo. We therefore investigated the influence of h-ANP on secretion reaction in human platelets. Eight healthy subjects, males, aged 20 to 24 years, donated blood for the study. Citrated platelet-rich plasma (PRP) was incubated with or without h-ANP at 37 C for 2.5 minutes. The samples of 0.5 ml PRP then used to measure ADP induced aggregation, ATP release reaction and C-serotonin release reaction. H-ANP, at concentration of 1x10 -6M, decreased ADP induced aggregation (after h-ANP: 77.4±9.7 % of control aggregation), and inhibited ATP release reaction (after h-ANP: 31.8±13.1%). Serotonin releasereaction induced by ADP was also inhibited ( control: 15.3±2.2%, after h-ANP: 8.3±0.5 %). The inhibitory effect of h-ANP on aggregation and secretion reaction was maximal by 3 minutes. These data suggest that h-ANP inhibits secretion reaction in human platelets.
ALTERATIONS OP THE ACTIN STATUS OP PLATELETS APPECTS THE FUNCTIONAL BEHAVIOUR OP THE CELL
Authors: Spangenberg P , Lobche W , Till U
Published: August 2018

Many platelet responses to agonists involve contractile proteins. Particularly, the status of the most abundant protein actin is changed in motile and contractile events. We have studied the effects of SH-reagents on platelets and found significant effects of a SH-oxidizing agent on the actin organization which are neutralized following the addition of a disulfide-reducing compound. SH-oxidation of intact platelets was achieved by incubation with diamide (azodicarboxylic acid-bis-dimethylamide). The P-actin of those cells is increased and the filaments became centralized indicating a disturbance of the membrane-cytoskeleton interaction. Treatment of SH-oxidized platelets with 2-mercaptopropionylglycine which reduces disulfides resulted in a return of P-actin levels to those seen in untreated cells The actin organization of platelets is discussed with regard to the altered functional behaviour of diamide-treated cells.
FURTHER CHARACTERIZATION OF PLATELET RELEASE MECHANISM DEFECT WITH DEFECTIVE A23187 AGGREGATION
Authors: Hattori A , Nagayama R , Fuse I , Takeshige T , Takizawa S , Shibata A
Published: August 2018

In order to clarify the basic abnormality of patients with release mechanism abnormality with defective response to A23187 (A23) (Hattori et al. Acta Haematol. Jap. 44:969, 1981), the proband (female) showing a life long mild hemorrhagic tendency was further examined. Her platelet (pit) count, morphology, storage pool was normal. Bleeding time (Duke) was more than 15 min.

PRP-aggregation (Ag) was normal when induced by PMA, whereas decreased (only primary Ag) by ADP, adrenalin, arachidonate (AA) (−2mM), Tx analog STA2 (−4μM), PAF (−10μM). Ag was defective in response to A23 (−40μM), Ag using washed pits was decreased slightly in response to thrombin or considerably to ionomycin. Adrenalin potentiation was observed in Ag and ATP release (R) by either AA or A23. Ca replacement (over 2mM) with heparinization normalized both Ag and R to those agonists, but Ca agonists did not improve the abnormality. Ca, Na and Cl contents were within normal range. Ca mobilization by Quin-2AM method occurred normally in response to thrombin (0.1, 0.5U/ml), and that by Aequo-rin method was also normal, but retarded with normal peak values in response to A23 and decreased to STA2. Shape change response to various agonists including A23 was normal. AA metabolite analysis by HPLC was normal, but Tx production was low by low dose of A23 but normal by high dose A23 and thrombin (serum). 20 and 40 K protein phosphorylation occured normally when challenged by high and low concentrations of A23 or thrombin, Clot retraction was normal.

These results suggest that the abnormality do not exsist in agonist-receptor reactions, enzymes related to production of Tx, Ca slow channel (if it exists), c-Kinase system, Ca content and amount of mobilizable Ca, actomyosin system, protein phosphorylation and reactions after Ca mobilization, but may exsist in activation of phospholipases and an early stage of Ca mobilization based on unknown defect(s).
REDISTRIBUTION OF PLATELET GLYCOPROTEINS INDUCED BY ALLO- AND AUTOANTIBODIES
Authors: Santoso S , Kiefel V , Mueller-Eckhardt C
Published: August 2018

It is now well established that two of the major membrane glycoproteins (GP) of human platelets, GP lb and Ilb/IIIa, are functionally prominent for adhesion, aggregation and carry the binding sites for allknown types of human platelet specific antibodies (ab). Although a number of in vitro effects of ab on platelet function have been described, the role of the GP specificity of the various ab with regard to membrane mobility and redistribution phenomena is asyet unknown.In this work, we studied the effect on platelet membrane redistribution of allo- ab, auto-aband a quinidine-dependent ab directed against various epitopes on GP lb, lib and Ilia using immunofluorescence and a quantitative radioimmunoassay. The platelet GP's carrying the corresponding epitopes were determined using immunoblot technique or radioimmuno-precipitation. When unfixed platelets were incubated with alio- or auto-ab against epitopes on GP liborGP IlIa cap formation and internalization of antigenantibody complexes were visualized by fluorescence. In contrast, no changes of antigen distribution were seen with auto-ab or quinidine- dependent ab directed against GP lb. To quantitate antigen-antibody complexes internalization a specially designed radioimmunoassay was employed. If unfixed platelets weretreated with allo- or auto-ab against GP lib or GP Ilia precipitous reduction of external radioactivity was found, whereas the total radioactivity remainedessentially unchanged. This indicated that a portionof approximately 50-70% of GP lib or GP Ilia had been removed from the platelet surface and had been internalized. Internalization could not be induced with auto-ab or quinidine dependent ab against GP lb.We conclude that membrane redistribution of human platelets can be induced by various human ab with specificity for GP lib and/or Ilia and is a function of the target GP rather than the source of therespective ab

Supported by Deutsche Forschungsgemeinschaft (Mu 277/9-6)
AN EPITOPE OF A MONOCLONAL ANTIBODY (TM83) AGAINST GLYCOPROTEIN lib/Ilia COMPLEX
Authors: Yamamoto N , Kitagawa H , Tanoue K , YAmazaki H
Published: August 2018

GPIIb/lIIa is forming a heterodimer complex on the human platelet membrane.Many monoclonal antibodiesagainst GPIIb/IIIa complex obtained elsewhere react with neither GPIIb nor GPIIIa separately when GPIIb/IIIa is blotted to filter after SDS-PAGE. Therefore the epitope of GPIIb/IIIa complex is not identified actually. Our attemption is to clarify the epitope recognized by a monoclonal antibody against GPIIb/IIIa designated TM83. TM83 (30 yg/ml) inhibited collagen-, ADP-, or thrombin-induced aggregation, but it did not inhibit ATP-secretion induced by 0.01 U/ml of thrombin. TM83 also inhibited fibrinogen-binding approximately to 50 % of total binding. The binding of 125 I- TM83 to platelets decreased to b0% of controlwhen platelets were incubated in the presence of 1 mM EDTA at 37°C for 30 min. However the incubation at25°C for 30 min did not change any binding capacity of 125 I-TM83 to platelets. Thus thebinding of TM83to platelets was dependent on both temperature and calcium concentration in surrouding medium, suggesting that TM83 bound to GPIIb/IIIa complex.

If the small amounts of epitope of GPIIb/IIIa complex is not injured during SDS-PAGE and blotting, we may identify clearly the epitope of GPIIb/IIIa complex. For this aim, GPIIb/IIIa complex was extracted carefully in the presence of 1 mM calcium by the phase separationusing Triton X-11U, and was run on SDS-PAGE in the presence of 100 yM calcium. Western-blot of the membrane preparation showed that 125 I-TM83 was incorporated into both GPIIb and GPIIIa on Durapore filter. Further radio-crossed immunoelectrophoresis showed that I-TM83 was incorporated only into immunoprecipitin of GPIIb/IIIa complex in the presenceof 1 mM calcium. While after addition of 25 mM EDTA to the membrane preparation containing 1 mM calcium,125i-tm83 wasmainly incorporated into GPIIb/IIIa complex as well, however very faint radioactivity fromthe immunoprecipitin corresponding to GPIIIa was observed, but the radioactivity from GPIIb was not identified. While there is a discrepancy inour result, it must be further studied whether one monoclonal antibody can recognize or not two kinds of GPs, GPIIb and Ilia, which are formed in complex in physiological condition.
FIBRIIOLYTIC ACTIVITY II THE IITBISIVE CARE PATIEIT
Authors: Garcia Frade L J , Landin L , Garcia Avello A , Bavarro J L , Creighton L J , Gaffney P J
Published: August 2018

Critically ill patients have been described to have blood coagulation abnormalities that predispose to bleeding and thrombosis.

We have studied plasminogen activators (fibrin plate, enzyme-linked Immunosorbent assay using polyclonalantibodies for t-PA), X-oligomers fibrin fragments (using monoclonal antibodies in an enzyme-linked immunosorbent assay), octant i pi asmin, antithrombtai III and fibronectin (Laurel1 innaunoeleetrophoretic technique), fibrinogen (thrombin timeassay), plateLets count, kaolln-cephalin clotting time and prothrombin time on admission to the intensive care unit and sequentially after 24 and 48 hours in 39 adult patients: Adult respiratory distress syndrome (ARDS) (n:6), Trauma (n:12), Sepsis (n:8), and Miscellanea (n:13).

A decrease in tissue plasminogen activator (ng/ml)(p<0.001, p<0.05, p<0.01, p<0.05, respectively in the four groups), associated to an increase in the earliest form of cross-linked fibrin degradation products, X-Oligomers concentration (ng/ml) (p<0.01), indicatethat fibrindeposition and fibrinolytic exhaustion is a widespread situation in the ICU patients. Fibronectin was significantly reduced (p<0.001) in ARDS and Sepsis patients, low fibronectin levels were related to prognosis (p<0.01).

These findings suggest.that critically ill patients, must be evaluated in respect to fibrinolysis and supported when necessary with prophylactic treatment.
PLATELET FUNCTION AND ENDOCRINE STRESS RESPONSE DURING BUPIVACAINE EPIDURAL ANALGESIA. THE EFFECT OF MORPHINE ADDITION
Authors: Nielsen T H , Nielsen H K , Husted S E , Hansen S L , Olsen K H
Published: August 2018

Platelet aggregation plays a central role in thromboembolism. Epidural analgesia can diminish the formation of deep venous thrombosis. In a randomized study twenty patients admitted to transartliroscopic meniscectomy were allocated to epidural analgesia with or without morphine epidurally. S-cortisol, s-thromboxane -B2(s-T2 B2) and platelet aggregation were measured before premedication, when epidural block extended from S3to T5, just before skin closure and exsufflation of tne thigh tourniquet, and the last sample was taken ten min after exsufflation. Aggregability was measured in platelet-rich plasma and expressed as the treshold concentration of collagen. Cortisol and T Bp were measured by RIA.S-cortisol decreased duringxanalgesia in the morphine group (p<o.o5), and during operation in both groups (p<o.o5) being significant lower in the morphine group (p<o.o5).S-TxB2 decreased significantly in the morphine group during analgesia, but there was no significant difference in s-TxB2 between the two groups. Treshold concentration of Collagen for aggregation of platelets showed an insignificant increase for both groups during analgesia, but did not differ between the two groups. Removal of the tourniquet did not influence any of the measurements. It is concluded that additionof morphine to bupivaca- ine epidural analgesia further decrease activity of the adrenocortical system, and the combined regime seems to inhibit platelet function in the same manner as monotherapy with local anaesthetics.
ISOLATION OF HUMAN PROTEIN C AND ITS SNAKE VENOM ACTIVATORS BY ION EXCHANGE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY
Authors: Dyr J E , Fořtová H , Suttnar J , Vorlová Z , Kornalxk F
Published: August 2018

Simple and efficient methods for the purification of functionally active clotting factors in good yields are still missing. The purpose of the present study was to design a chromatographic procedure for the isolation of protein C (PC) and its snake venom activators taking advantage of the high resolution, high speed of analysis and sensitive detection of high performance liquid chromatography.

PC was purified from a human plasma concentrate containing vitamin Kdependent proteins using a Mono Q anion exchanger. Electrophoretic titration curve was used to serve as a guide for finding approximate conditions for separations. Elution profiles for vitamin K-dependent proteins were determined. PC was assayed by both immunological and functional methods. For the latter methods, protein C activators (PCA) were isolated from snake venoms of Agkistrodon c, -contortrix (ACC) and Agkistrodon c, mokasen.Both venoms (pooled samples)were found to contain at least two different PCA. AtpH 6.5> by simple one step procedures either an acidic PCA (on a Mono Q) or a basic PCA (on a Mono S) was isolated. A great diversity was found among venom samples from specimen originating from a small geographic area near Philadelphia (USA). In six out of the nine analysed ACC venoms only the acidic PCA was present.

In conclusion, an optimum separationof protein C onthe Mono Q at pH 8.0 was proposed (usual recovery 90-95%).Optimalization of the salt gradient was considerably more effective than the pH changes. A great individual variability has to be taken into account when snake venoms are used as a source of protein C activators.
THE APPLICATIONS OF THE IMMUNOADSORBENT CHROMATOGRAPHY USING MO NOCLONAL ANTIBODY TO VON WILLEBRAND FACTOR
Authors: Ruan X Xi and C , Cheng D , Wan H
Published: August 2018

We have produced a group of monoclonal antibodiesto human von Willebrand factor (vWF) which specifically bound to human vWF but did not react with coagulation factors and other adhesive proteins, i.e. fibrinogen, fibronectin and thrombospondin. One of these antibodies, namely SZ _ 29, which bound to all multimers of vWF, was chosen for the immunoadsorbent chromatography. 15mg of purified SZ _ 29 IgG were coupled to 1.5g of BrCN activated Sepharose 4B gel. Theimmobilized IgG were packed into a glass column 1.0cm in internal diameter and 10cm in length, and equilibrated with 0.05M Tris buffer pH 7.4. 7ml of citrated normal plasma were applied to the top of the column. For better efficiency, the plasma was circulated in the column at a rate of 4ml/hour for 6 hours at10 'C and then was collected to measure the factor VIII procoagulant activity (VIII : C) and the levelof vWF. The remnants of VIII t C activity were 4.8% and of vWF were 0.5%, while the activities of other coagulation factors were normal. When the column waseluted with 3M NaCNS, pH 6.0 or 0.05M glycine, 0. 1MNaCl, pH 2.4, a narrow and small peak was monitored at 280nm. The elutes contained 0.1mg/ml of protein determined by Lowry method, and had a vWF level of 0.08 u/ml measured by an enzyme-1 inked immunosorbentassay. They failed to support the normal platelet agglutination indued by ristocetin.The relatively reduced vWF level and the loss of its function might becaused by the destruction of the structure during theelution procedure.On the basis of these results, we concluded that the monoclonal antibody SZ _ 29 couldserve as an efficient immunoadsorbent agent to produce immunodepleted plasma which was capable of being utilized as a substrate in the assay for VIII : C. Moreover, we can further reduce VIII : C activity in immunodepleted plasma by adding some other monoclonal antibodies to the system and enlarging the volumn of the affinity column. This monoclonal antibody-based chromatography system was also utilized for isolating fator VIII from factor VIII complex bound to the immobilized IgG when eluted with 0.25M CaCl2 solution. In the experiments mentioned above, all disadvantages arising from the use of heterologous antiserawere avoided.
Advancing the State of the Art in Clinical Natural Language Processing through Shared Tasks
Authors: Filannino Michele , Uzuner Özlem
Published: August 2018

Objectives: To review the latest scientific challenges organized in clinical Natural Language Processing (NLP) by highlighting the tasks, the most effective methodologies used, the data, and the sharing strategies.

Methods: We harvested the literature by using Google Scholar and PubMed Central to retrieve all shared tasks organized since 2015 on clinical NLP problems on English data.

Results: We surveyed 17 shared tasks. We grouped the data into four types (synthetic, drug labels, social data, and clinical data) which are correlated with size and sensitivity. We found named entity recognition and classification to be the most common tasks. Most of the methods used to tackle the shared tasks have been data-driven. There is homogeneity in the methods used to tackle the named entity recognition tasks, while more diverse solutions are investigated for relation extraction, multi-class classification, and information retrieval problems.

Conclusions: There is a clear trend in using data-driven methods to tackle problems in clinical NLP. The availability of more and varied data from different institutions will undoubtedly lead to bigger advances in the field, for the benefit of healthcare as a whole.