Browsing by Author "Alarcon, Marcelo"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Antiplatelet, anticoagulant, and fibrinolytic activity in vitro of extracts from selected fruits and vegetables
    (LIPPINCOTT WILLIAMS & WILKINS, 2011) Torres Urrutia, Constanza; Guzman, Luis; Schmeda Hirschmann, Guillermo; Moore Carrasco, Rodrigo; Alarcon, Marcelo; Astudillo, Luis; Gutierrez, Margarita; Carrasco, Gilda; Yuri, Jose A.; Aranda, Eduardo; Palomo, Ivan
    A diet rich in fruits and vegetables is known to decrease the risk of cardiovascular disease. However, the information regarding the antithrombotic activity (antiplatelet, anticoagulant, and fibrinolytic) of fruits and vegetables is scarce. The aim of this study was to assess the antithrombotic activity of extracts from fruits and vegetables widely consumed in central Chile. The study included samples of 19 fruits and 26 vegetables, representative of the local diet. The extracts prepared from each sample included an aqueous (juice or pressed solubles) and/or methanol-soluble fraction. The extracts were evaluated for antiplatelet, anticoagulant, and fibrinolytic activity in vitro at a final concentration of 1 mg/ml. The antiplatelet activity was assessed by platelet aggregation inhibition; anticoagulant activity was measured by the prothrombin time (PT), diluted prothrombin time (dPT), activated partial thromboplastin time (APTT), kaolin clotting time (KCT), and thrombin time. The fibrinolytic effect was determined with the euglobin clot lysis time and fibrin plate methods. Extracts of green beans and tomatoes inhibited platelet aggregation induced by ADP and arachidonic acid, in a concentration-dependent manner. The methanolic extracts of grapes prolonged the PT and dPT. Finally, extracts of raspberry prolonged the APTT and also presented fibrinolytic activity. In conclusion, from a screening that included a variety of fruits and vegetables, we found antiplatelet activity in green beans and tomatoes, anticoagulant activities in grapes and raspberries, whereas fibrinolytic activity was observed only in raspberries. Further investigations are necessary to advance in knowledge of the active compounds of these fruits and vegetables and their mechanisms of action. Blood Coagul Fibrinolysis 22:197-205 (c) 2011 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.
  • Thumbnail Image
    Item
    Val/Leu(247) and Trp/Ser(316) polymorphisms in beta(2) glycoprotein I and their association with thrombosis in unselected Chilean patients
    (SPRINGER, 2007) Palomo, Ivan; Pereira, Jaime; Alarcon, Marcelo; Vasquez, Marcela; Pinochet, Carmen; Poblete, Fernando; Mendez, Evelyn; Sandoval, Jeannette; Vidal, Rolando; Pierangeli, Silvia
    It is known that polymorphisms of beta (2)-glycoprotein I (beta (2)GPI) in exon 7 affect interaction between the phospholipid binding site and the antibodies, and that other polymorphisms in exon 8 increase the generation of antibodies. In this study, we analyzed genetic polymorphisms of beta (2)GPI in unselected Chilean patients to determine the prevalence of beta (2)GPI polymorphisms in the phospholipid domain in patients with venous and arterial thrombosis and the clinical correlation with thromboembolic complications. This study comprised 149 patients with venous and arterial thrombosis (62 with venous thrombosis and 87 with arterial thrombosis) and 160 healthy controls with no previous history of thrombosis. Polymorphisms of exons 7 and 8 of beta (2)GPI, which encode for its fifth domain, were determined by PCR-RFLP. The presence of aPL or anti-beta (2)GPI in the patients was detected by ELISA. Anti-beta (2)GPI were present in 8/149 patients (5.4%); of these, five had aCL antibodies of low titer. The allele containing Val/Leu(247) and Trp/Ser(316) was significantly more frequent in patients with thrombosis than in the control group (OR=3.1, CI 1.6-6.0, p=0.0003; OR=2.9, CI 1.1-8.6, p=0.027, respectively). These polymorphisms did not correlate with aPL or anti-beta (2)GPI but significant differences were observed with venous thrombosis (p=< 0.0001) and arterial thrombosis (p=0.026). In conclusion, the beta (2)GPI polymorphisms Val/Leu(247) and Trp/Ser(316) are not related to the presence of anti-beta (2)GPI antibodies in unselected Chilean patients with venous and arterial thrombosis, but they are significantly associated with venous and arterial thrombosis.