P2Y12 antagonist ticagrelor inhibits the release of procoagulant extracellular vesicles from activated platelets

Background: Activated platelets release platelet extracellular vesicles (PEVs). Adenosine diphosphate(ADP) receptors P2Y1 and P2Y12 both play a role in platelet activation, The present hypothesis hereinis that the inhibition of these receptors may affect the release of PEVs.Methods: Platelet-rich plasma from 10 healthy subjects was incubated with saline, P2Y1 antagonistMRS2179 (100 μM), P2Y12 antagonist ticagrelor (1 μM), and a combination of both antagonists.Platelets were activated by ADP (10 μM) under stirring conditions at 37°C. Platelet reactivity wasassessed by impedance aggregometry. Concentrations of PEVs– (positive for CD61 but negative forP-selectin and phosphatidylserine) and PEVs+ (positive for all) were determined by a state-of-the-artflow cytometer. Procoagulant activity of PEVs was measured by a fibrin generation test.Results: ADP-induced aggregation (57 ± 13 area under curve {AUC] units) was inhibited 73%by the P2Y1 antagonist, 86% by the P2Y12 antagonist, and 95% when combined (p < 0.001 for all).The release of PEVs– (2.9 E ± 0.8 × 108/mL) was inhibited 48% in the presence of both antagonists(p = 0.015), whereas antagonists alone were ineffective. The release of PEVs+ (2.4 ± 1.6 × 107/mL)was unaffected by the P2Y1 antagonist, but was 62% inhibited by the P2Y12 antagonist (p = 0.035),and 72% by both antagonists (p = 0.022). PEVs promoted coagulation in presence of tissue factor.Conclusions: Inhibition of P2Y1 and P2Y12 receptors reduces platelet aggregation and affects therelease of distinct subpopulations of PEVs. Ticagrelor decreases the release of procoagulant PEVs fromactivated platelets, which may contribute to the observed clinical benefits in patients treated with ticagrelor

The role of bracket fungi in creating alpha diversity of invertebrates in the Białowieża National Park, Poland

Bracket fungi are seen mainly as the cause of economic losses in forestry, and their role as creators of biodiversity is relatively poorly understood. The aim of the study was defining the manner in which the degree of decay (DD) of the fruiting bodies determines the character of the invertebrate assemblages colonising them. The effect of this group of fungi on the modification of biodiversity of invertebrates (Aranae, Opiliones, Pseudoscorpionida, two groups of mites- Mesostigmata and Oribatida, and Collembola and Insecta) was investigated by analyzing 100 fruiting bodies of 10 species of bracket fungi divided into four DD classes. The material was collected at Białowieża National Park, which is considered to be the largest area of natural forests in the North European Plain. 16 068 invertebrate individuals classified into 224 species were obtained. Oribatid mites (12 543 individuals) constituted the largest group of individuals, which were classified into 115 species with the most numerous Carabodes femoralis (8,811 individuals). Representatives of this group of mites have been reported previously in the publications on bracket fungi; however, the contributions of Oribatida and other groups of invertebrates were not broadly compared. Moreover, the species such as Hoploseius mariae and H. oblongus, which were predominantly found in fruiting bodies of bracket fungi, have also been discerned. The invertebrate fauna differs depending on DD of the samples: In the more decayed samples, a higher number of both individuals and species were recorded compared to the samples with lower DDs; however, this trend proved to be nonlinear. The DCA and cluster analysis revealed a similarity of the invertebrate assemblages from the 2 DD and 4 DD samples. They also indicated that the group 3 DD differed the most from all the other samples. The indicator species analysis identified species characteristic to individual DDs: For group 1 DD, it was, for example, Hoploseius oblongus; for 2 DD - Orchesella bifasciata; and for 3 DD-Chernes cimicoides, while for 4 DD-Dinychus perforatus

Hitchhiking through life: a review of phoresy in Uropodina mites (Parasitiformes: Mesostigmata)

Several important papers discussing phoretic dispersal in animals have appeared in recent years, but the nature and evolutionary significance of the phenomenon are still not fully understood. This article reviews the current knowledge of this behaviour in Uropodina mites, which disperse at the deutonymphal stage. We first examine the morphological and behavioural attributes of Uropodina deutonymphs involved in phoretic dispersal. We then provide a systematic review of the animals that carry Uropodina, and examine the carrier-specificity of 30 well-known species. Most species are associated with a single family of carriers, or at most, two families. The available information shows that phoretic deutonymphs of most species do not show any preference for male or female carriers. The spatial pattern of attachment of phoretic deutonymphs varies according to the identity of the carrier insect. The nature of deutonymph infestation depends on the size and morphology of both the mite and its carrier. Successful phoresy also depends on synchronisation of the life cycles of the mite and its carrier, but the temporal dynamics of phoresy remain particularly poorly studied. Phoresy has ecological and evolutionary consequences for both the Uropodina and their carriers. Future research on phoresy will benefit from studies of its evolutionary development, the reasons why beetles appear to be specially favoured as carriers, how phoretic mites affect the insect that carries them, and how the apparent global decline in insect populations is affecting their symbiotic mites

Switching between P2Y 12 antagonists – From bench to bedside

Platelet P2Y 12 receptors play a key role in platelet activation and thrombus formation. Accordingly, P2Y 12 receptor antagonists are the cornerstone of secondary prevention of atherothrombotic events in patients undergoing percutaneous coronary intervention (PCI). The availability of different oral P2Y 12 antagonists (clopidogrel, prasugrel, ticagrelor) along with the introduction of the first intravenous P2Y 12 antagonist cangrelor offer an opportunity to individualize antiplatelet therapy according to the changing clinical setting. The recent International Expert Consensus provided the first recommendations on switching between the P2Y 12 antagonists. While the consensus greatly helps to guide switching between P2Y 12 antagonists, a number of controversial clinical scenarios remain where the evidence regarding the optimal switch strategy is scarce. In such clinical scenarios, understanding of the (i) pharmacological properties of P2Y 12 antagonists, (ii) recent evidence from pharmacodynamics studies, clinical trials and registries, and (iii) factors affecting the efficacy and safety of the P2Y 12 antagonists, all summarized below, are crucial to choose the optimal switch strategy

Rola patogenów w kreowaniu różnorodności biologicznej. Wpływ rozkładających się hub na różnorodność gatunkową mikrostawonogów w Karkonoskim Parku Narodowym

Bracket fungi are organisms important to forestry, often perceived from the point of view of economic losses they cause, but they also play an important role in shaping biodiversity, e.g. by creating specific microhabitats to which their fruiting bodies belong. The fruiting bodies of this group of fungi are the place of occurrence of invertebrate assemblages specific for them, however, this topic is still poorly researched. The aim of the study was to assess the effect of the degree of decay (DD) of fruiting bodies on the microarthropod communities inhabiting them. The study material (100 fruiting bodies) was collected in the Karkonosze National Park, which areas were affected by a large-scale forest dieback process in the 1980s. 29,228 individuals of microarthropods belonging to 186 species were extracted. Oribatid mites were the most numerously represented group (87 species and 24,472 individuals) and the most numerous species was Carabodes femoralis (20,167 ind.). In addition to the species previously observed also in other substrates, species characteristic only for fruiting bodies of arboreal fungi were also observed (e.g. Hoploseius oblongus). Each DD's fauna differed from one another, in the majority of microarthropod groups there was a tendency for greater number of species and individuals in higher DDs; however, it was not a linear one. The NMDS and cluster analyses indicated that the 3 DD and 4 DD samples are similar to each other, whereas 1 DD and 2 DD samples differed from the samples belonging to the other DDs. Indicator species analysis has indicated species characteristic for each DD, among others Hoploseius oblongus for 1 DD and Zerconopsis remiger for 4 DD. The results encrease the knowledge on the poorly-understood aspekt of ecology and can be a useful source of information for effective protection of forest biodiversity and sustainable forest management

P2y12 antagonist ticagrelor inhibits the release of procoagulant extracellular vesicles from activated platelets

Background: Activated platelets release platelet extracellular vesicles (PEVs). Adenosine diphosphate (ADP) receptors P2Y1 and P2Y12 both play a role in platelet activation, The present hypothesis herein is that the inhibition of these receptors may affect the release of PEVs. Methods: Platelet-rich plasma from 10 healthy subjects was incubated with saline, P2Y1 antagonist MRS2179 (100 µM), P2Y12 antagonist ticagrelor (1 µM), and a combination of both antagonists. Platelets were activated by ADP (10 µM) under stirring conditions at 37°C. Platelet reactivity was assessed by impedance aggregometry. Concentrations of PEVs– (positive for CD61 but negative for P-selectin and phosphatidylserine) and PEVs+ (positive for all) were determined by a state-of-the-art flow cytometer. Procoagulant activity of PEVs was measured by a fibrin generation test. Results: ADP-induced aggregation (57 ± 13 area under curve {AUC] units) was inhibited 73% by the P2Y1 antagonist, 86% by the P2Y12 antagonist, and 95% when combined (p < 0.001 for all). The release of PEVs– (2.9 E ± 0.8 × 108/mL) was inhibited 48% in the presence of both antagonists (p = 0.015), whereas antagonists alone were ineffective. The release of PEVs+ (2.4 ± 1.6 × 107/mL) was unaffected by the P2Y1 antagonist, but was 62% inhibited by the P2Y12 antagonist (p = 0.035), and 72% by both antagonists (p = 0.022). PEVs promoted coagulation in presence of tissue factor. Conclusions: Inhibition of P2Y1 and P2Y12 receptors reduces platelet aggregation and affects the release of distinct subpopulations of PEVs. Ticagrelor decreases the release of procoagulant PEVs from activated platelets, which may contribute to the observed clinical benefits in patients treated with ticagrelor

Assessment of abundance and distribution of the Roman snail (Helix pomatia Linnaeus, 1758) in Kujawsko-Pomorskie voivodeship

Populations of Helix pomatia L. in Poland have been commercially exploited since 1951; the snails are mostly exported. The growing interest in the Roman snail on the European market has resulted in its increased exploitation, in some areas leading to a considerable decrease in its abundance. Introducing export quota in 1964 did not prevent overexploitation. Precise assessment of abundance and distribution of the Roman snail populations in areas where it is exploited is necessary. In 2009 the team from the Faculty of Biology, Adam Mickiewicz University in Poznań, conducted a preliminary assessment and mapping of the abundance and distribution of the Roman snail populations in Kujawsko-Pomorskie voivodeship. Most populations showed a low density. From scientific point of view the most reasonable solution would be to suspend exploitation in 2010 and continue monitoring, while decisions to issue permits for limited exploitation should be postponed till 2011. It would enable a more detailed estimation of the non-exploited populations and an assessment of losses resulting from exploitation of controlled reference populations. In this way acceptable limits of annual commercial collecting could be set for particular parts of the voivodeship