BACKGROUND: Aspirin is the most common drug used for the prevention of arterial thrombosis. However, platelet responsiveness to aspirin is variable among individuals and it is important to detect aspirin resistance to improve clinical outcome. We analyzed the changes of platelet reactivity before and after aspirin treatment. We also investigated the incidence and influencing factors of aspirin resistance in Korean. METHODS: We tested platelet function in 198 patients who had been treated with aspirin in a Korean university hospital, and 59 of these patients were tested for platelet function before and after aspirin treatment. We also analyzed platelet reactivity in 136 patients who had not been treated with aspirin. Platelet function was tested using the VerifyNow Aspirin Assay (Accumetrics, USA). Platelet reactivity was expressed as aspirin reaction unit (ARU) and > or =550 ARU was defined as aspirin resistance. RESULTS: Platelet reactivity of 136 patients who had not been treated with aspirin was 632.2+/-46.3 ARU (mean+/-SD) (range, 462-675). Platelet reactivity of 198 patients who had been treated with aspirin was 472.5+/-60.0 (338-666) ARU, and 10.1% of patients were aspirin-resistant. The difference of platelet reactivity before and after aspirin treatment was 128.3+/-68.7 (-40-248) ARU. Hb level was lower and platelet count was higher in aspirin-resistant group than in aspirin-sensitive group (P<0.05). CONCLUSIONS: We demonstrated the distribution of platelet reactivity before and after aspirin treatment using the VerifyNow Aspirin Assay. The incidence of aspirin resistance was 10.1%, and low Hb level and high platelet count were related with aspirin resistance.
Aged ; Aspirin/pharmacology/*therapeutic use ; Drug Resistance ; Female ; Hospitals, University ; Humans ; Korea/epidemiology ; Male ; Middle Aged ; Platelet Aggregation Inhibitors/pharmacology/*therapeutic use ; Platelet Function Tests ; Predictive Value of Tests

EDTA-dependent pseudothrombocytopenia (PTCP) is the phenomenon of a spurious low platelet count due to EDTA-induced aggregation of platelets. Since the failure to recognize EDTA-dependent PTCP may result in incorrect diagnosis and inappropriate treatment, the recognition of this phenomenon is very important. We report an insidious case of EDTA-dependent PTCP confirmed by supplementation of kanamycin to anticoagulant in a 53-year-old women. Although sodium citrate and heparin usually prevented the aggregation of platelets in EDTA-dependent PTCP patients, these anticoagulants failed in preventing PTCP in our case. EDTA-dependent PTCP was confirmed by the findings that the clumping of platelets on microscopic evaluation was found in EDTA-anticoagulated blood samples, whereas thrombocytopenia and platelet aggregation were not revealed in the sample supplemented with kanamycin.
Antibiotics, Aminoglycoside/*pharmacology ; Anticoagulants/*adverse effects/pharmacology ; Case Report ; Edetic Acid/*adverse effects ; Female ; Human ; Kanamycin/*pharmacology ; Middle Age ; Platelet Aggregation/*drug effects ; Platelet Aggregation Inhibitors/*therapeutic use ; Platelet Count ; Thrombocytopenia/*blood/chemically induced

OBJECTIVE: To evaluate correlation between and agreement in light transmittance aggregation (LTA) and thromboelastography (TEG) in laboratory diagnosing aspirin resistance (AR), and to determine the prevalence of AR in old patients. METHODS: Patients in the Wanshoulu District of Beijing with ischemic atherothrombotic diseases were recruited. Inclusion criteria were age ≥ 65 years, and having received regular aspirin therapy (75-100 mg daily) for at least 4 weeks. On the basis of LTA assay, the definition of AR was taken as aggregation of ≥ 20% with AA (arachidonic acid), and of ≥ 70% with ADP (adenosine diphosphate). Aspirin-sensitivity was indicated by the absence of either of these criteria; aspirinsensitivity was indicated as both criteria being met. The definition of AR by TEG is ≥ 50% via AA-induced whole blood aggregation. RESULTS: There were 13.69% prevalence of aspirin resistance for LTA using AA as the agonist, 30.16% prevalence of aspirin resistance for LTA using ADP as the agonist, and 23.67% prevalence of aspirin resistance for TEG using AA as the agonist. Results from these tests showed poor agreement (Kappa<0.4). However, by the method of LTA using AA and ADP as the agonists, prevalence of AR was 8.35%. By methods of AA-induced LTA and AA-induced TEG, prevalence of AR was 8.82%. Results from these two latter methods showed good agreement (Kappa = 0.793). CONCLUSION Combined methods, as described here, have good correlation and agreement in the assays of AR, and the results with them represent a realistic measure of the prevalence of AR. Prevalence of AR of elderly patients from Wanshoulu district of Beijing is about 9%.
Aged ; Aspirin ; pharmacology ; therapeutic use ; Cerebrovascular Disorders ; blood ; drug therapy ; Coronary Disease ; blood ; drug therapy ; Drug Resistance ; Female ; Humans ; Male ; Platelet Aggregation ; drug effects ; Platelet Aggregation Inhibitors ; pharmacology ; therapeutic use ; Prevalence ; Surveys and Questionnaires

Angioplasty, Balloon, Coronary ; adverse effects ; Aspirin ; pharmacology ; therapeutic use ; Coronary Angiography ; Drug-Eluting Stents ; adverse effects ; Humans ; Male ; Middle Aged ; Platelet Aggregation ; drug effects ; Platelet Aggregation Inhibitors ; pharmacology ; therapeutic use ; Sirolimus ; pharmacology ; therapeutic use ; Ticlopidine ; analogs & derivatives ; pharmacology ; therapeutic use ; Treatment Outcome ; Tyrosine ; analogs & derivatives ; pharmacology ; therapeutic use

AIM: The fruits of Lagenaria siceraria (Molina) Standl. (Cucurbitaceae), a commonly used vegetable, are reported to possess various medicinal properties. In previous studies, the fibrinolytic potential of an ethanolic extract of fruits of Lagenaria siceraria was investigated in comparison with kaempferol isolated from it. The aim of the present study was to explore its mechanistic antithrombotic potential and antiplatelet activity using a wide dose range in different in vitro and in vivo models, and to quantify the total phenolic, flavonoid, and kaempferol contents using a colorimetric method. METHOD: The antithrombotic potential was investigated using tail bleeding time in mice, a plasma recalcification assay, and pulmonary thromboembolism in mice. The antiplatelet activity was studied using an in vitro model to investigate IC50 value. RESULTS: A significant amount of total phenols, flavonoids, and kaempferol was quantified in L. siceraria ethanolic extract. An ethanolic extract of the fruits of L. siceraria showed a significant increase in tail bleeding time and plasma recalcification time, significant protection against ADP induced pulmonary thromboembolism in mice, and also inhibited the platelet aggregation induced by ADP in vitro. The study suggested that the fruits of L. siceraria exhibit significant antithrombotic potential due to inhibition of ADP-mediated platelet aggregation and the involvement of various non-cellular chemical mediators of blood. CONCLUSION This finding may be helpful in treating the serious consequences of the thrombus formed in blood vessels which include atherothrombotic diseases, such as myocardial or cerebral infarction. So, further investigation should be done for revealing exact mechanism of action behind these types of activities.
Adenosine Diphosphate ; Animals ; Calcium ; blood ; Cucurbitaceae ; chemistry ; Female ; Fibrinolytic Agents ; analysis ; pharmacology ; therapeutic use ; Fruit ; Goats ; Kaempferols ; analysis ; pharmacology ; therapeutic use ; Male ; Mice ; Phytotherapy ; Plant Extracts ; chemistry ; pharmacology ; therapeutic use ; Platelet Aggregation ; drug effects ; Platelet Aggregation Inhibitors ; analysis ; pharmacology ; therapeutic use ; Polyphenols ; analysis ; pharmacology ; therapeutic use ; Pulmonary Embolism ; blood ; chemically induced ; drug therapy ; Rats, Wistar ; Thrombosis ; prevention & control

Ginkgo biloba extract (GBE) is one of the hot spots of drugs extracted from plants recently; it protects brain from ischemia/reperfusion injuries. The mechanism of protective effects includes antioxidation, free radicals clearance, inhibiting the release of excitatory amino acid, anti-inflammation, inhibiting neural apoptosis and other biological effects.
Animals ; Antioxidants ; pharmacology ; therapeutic use ; Brain Ischemia ; complications ; drug therapy ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Ginkgo biloba ; chemistry ; Humans ; Phytotherapy ; Plant Leaves ; chemistry ; Platelet Aggregation Inhibitors ; pharmacology ; therapeutic use ; Reperfusion Injury ; prevention & control

Inonotus obliquus has high nutritional and medicinal value, especially in treating malignant tumors, diabetes, cardiovascular disease and AIDS, attracting significant attention from scholars in recent years. In this paper, the biological characteristics, chemical composition and pharmacologic effects of Inonotus obliquus were summarized. And the applications in medicine and food were introduced. Future research on Inonotus obliquus was also discussed in order to make Inonotus obliquus obtain effective exploitation and satisfy people's demands.
Anti-Inflammatory Agents ; chemistry ; pharmacology ; therapeutic use ; Antineoplastic Agents ; chemistry ; pharmacology ; therapeutic use ; Antioxidants ; chemistry ; pharmacology ; therapeutic use ; Antiviral Agents ; chemistry ; pharmacology ; therapeutic use ; Basidiomycota ; chemistry ; Biomedical Research ; trends ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; therapeutic use ; Humans ; Hypoglycemic Agents ; chemistry ; pharmacology ; therapeutic use ; Platelet Aggregation Inhibitors ; chemistry ; pharmacology ; therapeutic use ; Triterpenes ; chemistry ; isolation & purification

OBJECTIVETo evaluate the impact of different proton pump inhibitors on the antiplatelet activity of clopidogrel.

METHODSA total of 60 hospitalized patients undergoing percutaneous coronary intervention were randomly assigned to receive omeprazole group 40 mg/d (20 patients), pantoprazole group 40 mg/d (20 patients) and control group (20 patients). All patients also received standard clopidogrel therapy, continuing 30 days treatments. The percentage clotting inhibition was measured by the use of thrombelastogram and the maximal platelet aggregation rate (MPAR) was measured by turbidity method at the first day before admission and 15 or 30 days after treatment. Major adverse cardiac and cerebral events (MACCE) and hemorrhagic events within 30 days were recorded.

RESULTSThe baseline clinical characteristics, angiography and PCI result were compared among the three groups. At the first day before admission and 15 or 30 days after treatment, no significant difference was shown in the percentage clotting inhibition measured by thrombelastogram and the maximal platelet aggregation rate (MPAR) measured by turbidity method among the three groups. Though the platelet agglutination inhibition rate measured at 15 and 30 days increased and MPAR measured at 15 and 30 days declined compared with the baseline data (P < 0.05), no significant difference was found between levels measured at 15 and 30 days (P > 0.05). The rates of MACCE had no significant difference among the three groups. Compared with control group, the rates of hemorrhagic event were significantly decreased in omeprazole or pantoprazole group (P < 0.05), but no significant difference was shown between the omeprazole and pantoprazole group.

CONCLUSIONNo significant impact of different proton pump inhibitors on the antiplatelet activity of clopidogrel has been found in patients undergoing coronary stent implantation and short-time combined administration is safe.

2-Pyridinylmethylsulfinylbenzimidazoles ; pharmacology ; therapeutic use ; Adult ; Aged ; Angioplasty, Balloon ; Aspirin ; pharmacology ; therapeutic use ; Coronary Disease ; therapy ; Drug Therapy, Combination ; Female ; Humans ; Male ; Middle Aged ; Omeprazole ; pharmacology ; therapeutic use ; Platelet Aggregation ; drug effects ; Postoperative Period ; Proton Pump Inhibitors ; pharmacology ; therapeutic use ; Stents ; Ticlopidine ; analogs & derivatives ; pharmacology ; therapeutic use

OBJECTIVETo assess the significance of platelet activation in unstable angina pectoris (UA) and acute myocardial infarction (AMI), and to explore the relationship of clinical effect of Xuefu Zhuyu concentrated pill (XCP) in vivo and the serum pharmacological anti-platelet activating effect of XCP in vitro.

METHODSBy flow cytometry and special labelled antibodys to detect the whole blood platelet membranous glycoprotein CD62P and CD41/45 expressions in UA patients before and after XCP treatment, as well as those in peripheral blood of AMI rats before and after co-cultured with XCP containing serum from patients at 37 degrees C for 30 min.

RESULTSCD62P and CD41/45 expressions increased significantly in UA patients to 24.36 +/- 7.91% and 29.51 +/- 12.21% respectively. After effective treatment, they decreased to 19.57 +/- 7.22% and 20.87 +/- 8.73% respectively accompanied with increase of platelet adhesion and aggregation rate. The difference of CD62P before and after treatment was significant (P < 0.05). CD62P in blood of AMI rats was 39.73 +/- 12.36%, after being co-cultured with XCP containing serum from patients treated effectively, it reduced to 30.41 +/- 10.36% (P < 0.05), but after co-cultured with the serum from patients treated ineffectively, it showed less intervention effect (P > 0.05).

CONCLUSIONPlatelet was highly activated in UA patients and AMI rats. The consistency between clinical holistic effect of XCP and serum pharmacological effect of XCP in platelet activation inhibition reflects a good correlation between serum pharmacological effect of Chinese herbal medicine and its clinical holistic effect.

Aged ; Angina, Unstable ; blood ; drug therapy ; Animals ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; blood ; P-Selectin ; blood ; Phytotherapy ; Platelet Activation ; drug effects ; Platelet Aggregation Inhibitors ; pharmacology ; therapeutic use ; Platelet Membrane Glycoprotein IIb ; blood ; Rats ; Rats, Wistar

BACKGROUNDAspirin is widely used in the secondary prevention of coronary artery diseases, including myocardial infarction, stroke, and vascular related deaths. However, the antiplatelet effect of aspirin appears to be variable and aspirin resistance (AR) is currently still controversial for Chinese patients. The aim of this study was to describe the prevalence of AR, and identify possible risk factors associated with a lack of response to aspirin treatments in patients with unstable coronary artery disease.

METHODSPlatelet function tests with arachidonic acid (ARA) and urinary 11-dehydro-thromboxane B2 (11-DH-TXB2) concentrations were performed in 262 patients with unstable coronary artery disease who had not been taking aspirin before admission. ARA induced platelet aggregation and 11-DH-TXB2 were detected to evaluate the functional and biochemical responses to aspirin before and on days 1, 4, and 10 after aspirin administration. Six-month follow-up was completed in patients who developed AR to evaluate the effect of aspirin in a long-term treatment. GP1Bα (C1018T), Pl (A1/A2), P2Y1 (A1622G), TBXA2R (T924C) were also detected to evaluate the influence of genetic variant on aspirin responsiveness.

RESULTSA total of 8.8% of patients were indentified as AR at the first day after aspirin treatment. The level of urine 11-DH-TXB2 in the AR group was higher compared to non-AR group (P < 0.05). There was no relationship between ARA induced platelet aggregation and urinary 11-DH-TXB2 levels (r = 0.038, P = 0.412). The results of DNA sequencing showed that TBXA2R-924TT homozygotes had a significantly high rate of AR. Logistic regression demonstrated that diabetes was an independent risk factor of AR.

CONCLUSIONSIn the beginning period of administration, aspirin was not a sufficient factor that inhibits platelet aggregation. TBXA2R-924T allele was involved in AR. Diabetes was an independent risk factor of AR.

Aged ; Aged, 80 and over ; Arachidonic Acid ; pharmacology ; Aspirin ; therapeutic use ; Coronary Artery Disease ; drug therapy ; genetics ; Diabetes Mellitus, Type 2 ; Female ; Genotype ; Humans ; Male ; Membrane Glycoproteins ; genetics ; Middle Aged ; Platelet Aggregation ; drug effects ; Platelet Aggregation Inhibitors ; therapeutic use ; Platelet Function Tests ; Platelet Glycoprotein GPIb-IX Complex ; Polymerase Chain Reaction ; Polymorphism, Genetic ; genetics ; Receptors, Purinergic P2Y1 ; genetics ; Receptors, Thromboxane A2, Prostaglandin H2 ; genetics ; Thromboxane B2 ; analogs & derivatives ; urine