196,307 research outputs found
Inhibition of the platelet P2Y12 receptor for adenosine diphosphate potentiates the antiplatelet effect of prostacyclin
No full textBackground: Activation of two receptors for adenosine diphosphate (ADP), P2Y1 and P2Y12, is necessary for ADP-induced platelet aggregation (PA). It is generally believed that the antithrombotic effects of drugs inhibiting P2Y12, such as clopidogrel, are uniquely mediated by inhibition of P2Y12 -dependent PA. However, as P2Y12 is negatively coupled to adenylyl cyclase (AC), its inhibition may also exert antithrombotic effects through the potentiation of prostacyclin (PGI2), which inhibit PA by stimulating AC. Objectives: To test whether inhibition of P2Y12 potentiates the antiplatelet effects of PGI2. Methods: We measured the effects of PGI2 (0.01-10 μ m) on PA of washed human platelets induced by thrombin (0.5 U mL-1) in the presence or absence of ARC69931MX (anti-P2Y2) or MRS2500 (anti-P2Y1). Results: PGI2 inhibited PA in the presence of anti-P2Y12, but not in the presence of anti-P2Y1 or in the absence of inhibitors. In contrast, dibutyryl-cyclicAMP inhibited PA both in the presence and absence of anti-P2Y1 or anti-P2Y12. PGI2 increased platelet cyclicAMP levels only in the absence of thrombin or in the presence of thrombin plus anti-P2Y12. Conclusions: PGI2 did not inhibit PA induced by thrombin, because its effect on AC was prevented by released ADP interacting with P2Y12. Anti-P2Y12 drugs, by rescuing AC activity, potentiate the antiplatelet effect of PGI2, which may contribute to their antithrombotic effect
Patients with congenital abnormality of platelet aggregation induced by Ca2+ ionophores may have a defect of the platelet P2Y(12) receptor for ADP
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Jesuit connections: Ruggiero G. Boscovich and Giovanni A. Lecchi
No full textIl lavoro presenta un quadro della vita di Ruggiero G. Boscovich durante il periodo da lui trascorso in Lombardia tra il 1763 ed il 1770. Boscovich fu prima professore di matematica all'Università di Pavia, poi alle Scuole Palatine di Milano. Alcuni manoscritti documentano questo importante periodo della sua vita, che precede di pochi anni la soppressione della Compagnia di Gesù.The present work provides a framework of Ruggiero Giuseppe Boscovich’s life during his stay in Lombardy in the period 1763-1770. He was called in Pavia as a professor of mathematics in the local University. Some unpublished manuscripts well document this important period in the life of the Jesuit. The first one represents a list of scientific books Boscovich suggests for the University Library of Pavia. Another source of information is a collection of twenty-two letters, written by Giovanni Antonio Lecchi to Boscovich in the period 1763-1770. This correspondence foreruns the canonical suppression of the Society of Jesus (1773)
Variability of [F-18]FDG administered activities among patients undergoing PET examinations : An international multicenter survey
No full textGiven the large number of [(18)F]fluorodeoxyglucose (FDG) PET examinations performed annually throughout the world, reduction of the administered activity without compromise of the clinical information being sought is encouraged. Guidelines issued by the SNMMI and European Association of Nuclear Medicine (EANM) differ greatly on the choice of the activity that should be administered to patients: the EANM suggests a personalised activity based on the patient's body weight, whereas the SNMMI recommends the administration of fixed activities. The authors analysed a database of 24 716 [(18)F]FDG administrations performed worldwide in 15 PET centres to assess the degree of heterogeneity, in relation to available technology, operational protocols and reference guidelines. Median activities based on the patients' body weight were 43 % lower than fixed-activity administrations (p < 0.001). When TOF scanners are available, the median activity is lowered, but when comparing centres with the same technology or those that use the same operational protocols, weight-based activities are still significantly lower than fixed activities
JHC766292_Supplemental_Figure_1_online_supp – Supplemental material for Immunohistochemical Expression of FXR1 in Canine Normal Tissues and Melanomas
No full textSupplemental material, JHC766292_Supplemental_Figure_1_online_supp for Immunohistochemical Expression of FXR1 in Canine Normal Tissues and Melanomas by Laura Nordio, Andreia T. Marques, Cristina Lecchi, Alberto M. Luciano, Damiano Stefanello and Chiara Giudice in Journal of Histochemistry & Cytochemistry</p
Effective and equivalent dose minimization for personnel in PET procedures : how far are we from the goal?
No full textDifferent susceptibility of local Apulian and Calabrian grapevines to downy mildew and characterization of Plasmopara viticola populations
No full textDowny mildew, a severe grapevine disease worldwide, is caused by different cryptic species of Plasmopara viticola. Several approaches are under study to reduce the impact of chemicals in the disease management, including the selection of resistant genotypes for grapevine breeding. In this study, the susceptibility of six different local wine grape cultivars was assessed on leaves and bunches, in 2023, an year particularly favourable to the downy mildew epidemy. Based on McKinney's index (MKI: 37.3 to 52.6%), Marchione, Moscato reale, Maresco and Moscato di Terracina were more susceptible than Moscato di Trani, Trebbiano and Verdeca, classified as resistant ones (MKI: never exceeding 16.6%). Additionally, the genetic variability of P. viticola populations infecting grapevine in Apulia, Calabria and Lombardia was evaluated. Sporangia were collected from oil-spots in 26 vineyards (15 Apulia, 11 Calabria), during 2023 and 2024 years. The CAPS analysis was carried on restriction enzyme AseI profiles of the amplified DNA using the ITS1-O/ITS2, according to Rouxell et al. (2013). A total of 130 isolates and 20 DNA samples from oil spots sampled in Lombardia were analysed. All belong to the clade aestivalis, as also confirmed by BLASTn analysis of the ITS partial sequence of few representative isolate of Apulia and Calabria regions. These preliminary results suggest that the resistant behaviour of analysed grapevine genotypes is limited to P. viticola clade aestivalis and highlight the opportunity to preserve the local biodiversity for possible introduction of new P. viticola clades, currently absent
Platelets from a patient heterozygous for the defect of P2(CYC) receptors for ADP have a secretion defect despite normal thromboxane A(2) production and normal granule stores - Further evidence that some cases of platelet 'primary secretion defect' are heterozygous for a defect of P2(CYC) receptors
No full textEffect of platelet count on platelet aggregation measured by impedance aggregometry (Multiplate(TM) analyser) and by light transmission aggregometry
No full textThe in vitro evaluation of platelet aggregation is useful to diagnose platelet function disorders [1, 2]; in some laboratories, the test is also used to monitor antiplatelet treatment [3]. Traditionally, platelet aggregation is measured by light transmission aggregometry (LTA), which measures the changes in transmission of a beam of light through a sample of platelet-rich plasma (PRP) or platelet suspensions in buffer, which occur when platelets change shape and aggregate upon stimulation. As this technique has some disadvantages [2], novel methods were introduced to measure platelet aggregation in vitro
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