scholarly journals Variability of Platelet Function Response to Aspirin

1977 ◽  
Author(s):  
M. Atik
Keyword(s):  
Rheumatoid Arthritis ◽  
Platelet Aggregation ◽  
Platelet Function ◽  
Glass Bead ◽  
Platelet Adhesiveness ◽  
Turbidimetric Method ◽  
Normal Individuals ◽  
Massive Gastrointestinal Bleeding ◽  
The Mean

To evaluate the effect of aspirin on platelet function, three groups of subjects were studied. Platelet adhesiveness (pl. adh.) was determined by the Hellem glass bead retention method, and platelet aggregation (pi. agg.) by the Born turbidimetric method using standardized collagen of various dilution. In eight healthy volunteers, the mean pl. adh. decreased insignificantly from 45% ± 13 to 41% ± 13 after 5-7 days of 600 mg/day of aspirin. They showed slight to moderate impairment of platelet aggregation. In 16 patients with massive gastrointestinal bleeding, following ingestion of aspirin, the mean pl. adh. was 22% ± 5 which is significantly lower (P<0.01) than for the normal individuals. These patients showed poor to no platelet aggregation. By contrast in 14 patients with rheumatoid arthritis, despite being on large doses of aspirin, the mean pl. adh. was 61% ± 15 which is significantly higher (P<0.05) than for the non-arthritics. In six.: of these patients pl. agg. was also measured. They showed no or slight impairment. These observations provide a plausible explanation for the conflicting reports regarding efficacy and complications of aspirin and emphasize the need to differentiate between its anti-inflammatory and antithrombogenic effects by actual determination of platelet function in patients treated with aspirin.

Disturbance Of Platelet Function In The Nephrotic Syndrome

1981 ◽  
Author(s):  
E Walter ◽  
D Deppermann ◽  
K Andrassy ◽  
E Weber
Keyword(s):  
Nephrotic Syndrome ◽  
Platelet Count ◽  
Platelet Aggregation ◽  
Kidney Function ◽  
Platelet Function ◽  
Platelet Adhesiveness ◽  
Spontaneous Aggregation ◽  
Spontaneous Platelet Aggregation ◽  
Platelet Functions

Thromboembolic phenomena often (30 %) complicate the nephrotic syndrome. It was therefor investigated, wether disturbed platelet functions play a role in this disease.28 normals, 34 patients with nephrotic syndrome and 18 of them with impaired kidney function were tested. In 20 patients the measurements were repeated after administration of aspirin plus dipyridamo1e.Patients with nephrotic syndrome showed in comparison to normals the following changes: 1. increased platelet count (p < 0.01), 2. enhanced platelet adhesiveness (Wright-test: p < 0.001), 3. increased spontaneous aggregation (PAT I: p < 0.001; PAT III: p < 0.01), 4. enhanced PF 4-activity (heparin neutralisation: p < 0.001), 5. elevated β TG-levels only in impaired kidney function. There was no difference in the reaction of platelets against ADP as well as collagen. The changes in platelet function correlated with the severity of the nephrotic syndrome (proteinurea, hypalbuminaemia, hyperlipo- proteinaemia). After aspirin plus dipyridamole administration spontaneous platelet aggregation and adhesiveness were normalized.There is a disturbance of platelet function in patients with nephrotic syndrome, which can be reversed with antiaggregating agents.

Platelet Retention in Glass Bead Columns: Further Evidence for the Importance of ADP

Blood ◽  
1974 ◽  
Vol 44 (3) ◽  
pp. 411-425 ◽  
Author(s):  
V. J. McPherson ◽  
M. B. Zucker ◽  
N. M. Friedberg ◽  
P. L. Rifkin
Keyword(s):  
Platelet Aggregation ◽  
Acetylsalicylic Acid ◽  
Glass Bead ◽  
Room Temperature ◽  
Creatine Phosphokinase ◽  
Platelet Rich Plasma ◽  
Creatine Phosphate ◽  
Inhibitory Effect ◽  
Normal Platelet ◽  
Normal Individuals

Abstract Plasma of normal heparinized blood contained 0.284 µM ± SD 0.097 (ADP + ATP) with an ATP:ADP ratio of 2.5:1. Plasma from thrombocytopenic blood contained only 0.106 µM ± 0.073 (ADP + ATP). Blood with normal platelet retention released 0.234 µM ± 0.187 (ADP + ATP) during passage through a glass bead column, with an ATP:ADP ratio of 1.6:1. Significantly less was released in blood with low retention, i.e., samples from patients with von Willebrand’s disease, thrombasthenia, or thrombocytopenia, and some samples from normal individuals. Thus, nucleotides in the plasma of pre- and postcolumn blood appear to be derived from platelets; their release within glass bead columns is closely associated with normal platelet retention. Since release occurred at room temperature and was not prevented by acetylsalicylic acid or accompanied by measurable release of 14C-serotonin, the classic release reaction may not have been responsible. The low retention in platelet-rich plasma was variably increased by adding 0.5 µM ADP, an increase at least partly due to trapping of preformed aggregates. Retention in undisturbed blood was markedly inhibited by creatine phosphokinase with creatine phosphate (CPK-CP) and moderately inhibited by apyrase I (ATPase:ADPase 0.8:1) at an ADP-removing activity between 1 and 5 U/ml, indicating that ADP is essential for retention. At less than 1 U/ml, both apyrase I and II (ATPase: ADPase 2.8:1) enhanced retention in undisturbed blood, but CPK-CP was still inhibitory. These results suggest that enhancement is due to conversion of released ATP to ADP, as shown to occur in studies of platelet aggregation with ATP and ADP. At less than 1 U/ml, all three enzymes protected against the inhibitory effect of disturbance; this protection was marked with apyrase II, moderate with apyrase I and slight with CPK-CP. These observations provide additional evidence that ADP is responsible for the low retention caused by disturbance of the blood.

Determination of the reference range of platelet aggregation using a new automatic coagulation analyzer and visualization of platelet function data

2020 ◽  
Vol 194 ◽  
pp. 95-97
Author(s):  
Makiko Yoshida ◽  
Kazumasa Oura ◽  
Mie Shimizu ◽  
Tatsunori Natori ◽  
Shinsuke Narumi ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Platelet Function ◽  
Reference Range ◽  
Function Data ◽  
Coagulation Analyzer

Development of Radioimmunoassay for Gamma-Glutamyl Transferase Using Pancreatic Enzyme

1983 ◽  
Vol 20 (4) ◽  
pp. 247-250 ◽  
Author(s):  
Masanobu Masuike ◽  
Michio Ogawa ◽  
Takeshi Kitahara ◽  
Atsuo Murata ◽  
Kazuhiko Matsuda ◽  
...  
Keyword(s):  
Enzyme Assay ◽  
Pancreatic Enzyme ◽  
Gamma Glutamyl Transferase ◽  
Gamma Glutamyl ◽  
Standard Curve ◽  
Normal Individuals ◽  
The Mean ◽  
Glutamyl Transferase ◽  
Dilution Curves

A radioimmunoassay (RIA) for the determination of gamma-glutamyl transferase (GGT) was developed using human pancreatic enzyme as antigen. The assay allows the determination of GGT in concentrations as low as 80 ng/ml, and it is reproducible and specific. A good parallel relation was demonstrated between the standard curve and dilution curves for serum, urine, bile, and partially purified kidney GGT. In normal individuals, the mean serum concentration of GGT determined by RIA was found to be 3·43 μg/ml (SD ± 1·20). Enzyme activity calculated from the GGT concentration measured by the radioimmunoassay using a regression equation was approximately twice as great as that determined by conventional enzyme assay.

Liquid Chromatographic Determination of Salinomycin Sodium in Feed Premix and Biomass Samples

1987 ◽  
Vol 70 (3) ◽  
pp. 504-506 ◽  
Author(s):  
Gary P Dimenna ◽  
James A Creegan ◽  
Lennox B Turnbull ◽  
George J Wright
Keyword(s):  
Extraction Method ◽  
Chromatographic Determination ◽  
Turbidimetric Method ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Determination ◽  
The Mean ◽  
Feed Premix ◽  
Liquid Chromatographic ◽  
Refractive Index Detection

Abstract A liquid chromatographic (LC) method has been developed for determination of sodium salinomycin (SS) in feed premix and biomass samples. SS is extracted from samples with acetonitrile, and the extract is diluted to volume. An aliquot is then injected directly into the chromatographic column, and refractive index detection is used to determine the presence of SS. The LC method proved to be both fast and specific; SS was quickly separated from lasalocid, monensin, and narasin. To test the efficiency of this extraction method, premix and biomass samples were spiked with SS. The mean recovery of SS from the spiked premix samples was 101.6%, and from the spiked biomass samples, 99.4%. Six premix samples were then assayed for SS in triplicate on 5 successive days, and 10 biomass samples were assayed for SS in triplicate on 3 different days. The coefficients of variation for the premix assay values ranged from 2.50 to 7.87%. For the biomass assay, CVs ranged from 0.9 to 3.5%. Premix and biomass samples were assayed for SS by this LC method in 2 laboratories and by a turbidimetric method using Bacillus subtilis in a third laboratory. The assay values obtained for SS were equivalent.

scholarly journals Identification ofITGA2BandITGB3Single-Nucleotide Polymorphisms and Their Influences on the Platelet Function

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Qian Xiang ◽  
Shun-Dong Ji ◽  
Zhuo Zhang ◽  
Xia Zhao ◽  
Yi-Min Cui
Keyword(s):  
Platelet Aggregation ◽  
Platelet Function ◽  
Bleeding Time ◽  
Clinical Importance ◽  
Adenosine Diphosphate ◽  
Thrombin Time ◽  
Nucleotide Polymorphisms ◽  
Coding Region ◽  
Minor Alleles ◽  
The Mean

The aim of the study was to investigateITGA2BandITGB3genetic polymorphisms and to evaluate the variability in the platelet function in healthy Chinese subjects. The genetic sequence of the entire coding region of theITGA2BandITGB3genes was investigated. Adenosine diphosphate-induced platelet aggregation, glycoprotein IIb/IIIa content, bleeding time, and coagulation indexes were detected. Thirteen variants in theITGA2Blocus and 29 variants in theITGB3locus were identified in the Chinese population. The rs1009312 and rs2015049 were associated with the mean platelet volume. The rs70940817 was significantly correlated with the prothrombin time. The rs70940817 and rs112188890 were related with the activated partial thromboplastin time, andITGB3rs4642 was correlated with the thrombin time and fibrinogen. The minor alleles of rs56197296 and rs5919 were associated with decreased ADP-induced platelet aggregation, and rs55827077 was related with decreased GPIIb/IIIa per platelet. The rs1009312, rs2015049, rs3760364, rs567581451, rs7208170, and rs117052258 were related with bleeding time. Further studies are needed to explore the clinical importance ofITGA2BandITGB3SNPs in the platelet function.

Reduced platelet function in subarachnoid hemorrhage

1986 ◽  
Vol 64 (6) ◽  
pp. 907-910 ◽  
Author(s):  
Sotirios A. Tsementzis ◽  
Jaswinder S. Gill ◽  
Edward R. Hitchcock ◽  
Jennifer A. Hartley ◽  
Surinder K. Gill ◽  
...  
Keyword(s):  
Platelet Count ◽  
Subarachnoid Hemorrhage ◽  
Platelet Aggregation ◽  
Platelet Function ◽  
Maximum Rate ◽  
Adenosine Diphosphate ◽  
Platelet Adhesiveness ◽  
Content Type ◽  
Aneurysmal Rupture ◽  
Fine Print

✓ The hypothesis that abnormalities of platelet function may relate to the occurrence or recurrence of subarachnoid hemorrhage (SAH) has been examined. Seventy patients with SAH and 65 control individuals were studied. The adenosine diphosphate (ADP) threshold for secondary platelet aggregation was significantly higher in the SAH group than in the controls. In tests using 4.0 µg/ml ADP, the percent platelet aggregation (at 2 minutes) and the maximum rate of platelet aggregation (over 20 seconds) were significantly lower in the SAH patients. There was no difference in total platelet count between the two groups. Platelet adhesiveness was lower in the SAH patients when compared to controls. Circulating microaggregates did not differ between the two groups. The results indicate that reduced platelet function does relate to SAH and may either contribute to aneurysmal rupture in cases of SAH or be a consequence of it.

The Platelet Function of the Thrombopathy on the Åland Islands

1964 ◽  
Vol 12 (01) ◽  
pp. 148-168 ◽  
Author(s):  
W Lehmann ◽  
J Jürgens ◽  
Aldur W. Eriksson
Keyword(s):  
Platelet Function ◽  
Venous Blood ◽  
Time Increase ◽  
Platelet Adhesiveness ◽  
Clotting Time ◽  
Clot Retraction ◽  
Haemorrhagic Diathesis ◽  
Tissue Thromboplastin ◽  
Glass Surfaces

SummaryIn the summer of 1962 we checked a total of 20 bleeders from Åland in order to elucidate the pathogenesis of the haemorrhagic diathesis on the Åland Islands/Finland (“hereditary pseudohaemophilia” – “constitutional thrombopathy” – “v. Willebrand’s disease”). They partly belong to the same families described in 1933 by v. Willebrand and R. Jürgens. We came to the following results :1. On the determination of the volumetric retraction under consideration of the heamatocrit value 17 of 19 patients presented a hyporetractility of the coagulum.2. The thrombelastogram showed in 14 out of 18 patients a completely normal blood coagulation and only in 4 cases a very slight prolongation of the clotting time (increase of r and k).3. The clot retraction disturbance could not be normalized by adding tissue thromboplastin to the venous blood of the 4 patients with mild hypocoagu-laemia mentioned under no. 2. The hyporetractility of the coagulum can therefore not be due to the hypocoagulaemia or a lack of the intrinsic system of thromboplastin generation.4. In 18 out of 19 patients there was a partially extremely decreased platelet adhesiveness on glass surfaces.5. In 17 out of 19 patients a disorder of the platelet agglomeration in citrated plasma released by the effect of glass surfaces was established.6. 14 out of 16 patients showed a pathologic rotation thrombelastogram.7. It is possible, but not yet proved that all these phenomenons are caused by the decreased platelet adhesiveness on glass. In any case, however, the decreased platelet adhesiveness on glass speaks in favor of a disturbed platelet function which could possibly play a part in the development of the haemostatic defect in this disease. Whether we are dealing with an endothrombocytic defect, or whether the decreased adhesiveness on glass presents a secondary disorder of the platelet function due to the lack of an antibleeding factor, is another question which could not yet be definitely settled. Investigations concerning this question are continued.

Determination of Urine Dopamine

1962 ◽  
Vol 8 (4) ◽  
pp. 370-377 ◽  
Author(s):  
Fritz Bischoff ◽  
Adolfo Torres
Keyword(s):  
Acetic Acid ◽  
Room Temperature ◽  
Cirrhosis Of The Liver ◽  
Internal Standards ◽  
Mean Values ◽  
Normal Individuals ◽  
Reaction Proceeds ◽  
Urinary Dopamine ◽  
The Mean

Abstract The Duliere and Raper conversion of dopamine to 5,6-hydroxyindole is applied to urinary dopamine, which is concentrated and recovered by adsorption (pH 8.5-9.0) on and elution with dilute acetic acid from alumina. The spectrofluorometric readings are made at pH 5.3, with activation and fluorescence at 320 and 375 mµ, respectively. Proportionality between high and low internal standards is achieved when the 5,6-hydroxyindole reaction proceeds for 20 hours at room temperature. The increase of fluorescence with time adds specificity to the test. The recovery of standards added before adsorption on alumina compared with standards added after elution was 98 per cent. Urinary dopamine was determined in normal individuals asleep and awake and in those with a number of pathologic conditions. The mean values were decreased in groups with Parkinsonism, diabetes, and cirrhosis of the liver. The study included 2 patients with pheochromocytoma.

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