Biomarkers of platelet activation in thoroughbreds during their first long-term training.

Physical exercise has an activating effect on platelet function that differs between trained and untrained subjects, depending on the type of exercise and training status. In humans, soluble P-selectin (sP-sel) and platelet-derived extracellular vesicles (PEVs) are considered reliable markers of platelet activation during exercise. In untrained humans, they increase after transient physical exercise, whereas long-term training induces a decrease in their resting levels due to an improved ability to adapt to hemodynamic changes.

Effect of Regular Training on Platelet Function in Untrained Thoroughbreds.

Training has a significant effect on the physiology of blood coagulation in humans and in horses. Several hemostatic changes have been reported after exercise in the horse but data available are inconclusive. The aim of this study was to investigate platelet activation and primary platelet-related hemostasis modifications in young never-trained Thoroughbreds in the first incremental training period in order to improve knowledge on this topic.

The Unusual Dominance of the Yeast Genus in the Deeper Layer in an Antarctic Permafrost Core (Adélie Cove, Northern Victoria Land) Is Driven by Elemental Composition.

Rock glaciers are relatively common in Antarctic permafrost areas and could be considered postglacial cryogenic landforms. Although the extensive presence of rock glaciers, their chemical-physical and biotic composition remain scarce. Chemical-physical parameters and fungal community (by sequencing the ITS2 rDNA, Illumina MiSeq) parameters of a permafrost core were studied.

High-on-treatment platelet reactivity predicts adverse outcome after carotid artery stenting: A prospective study.

Background And Purpose: High-on-treatment platelet reactivity (HTPR) has been established as a predictor of major adverse cardiovascular events (MACE) in patients undergoing percutaneous coronary interventions on dual antiplatelet therapy (DAPT), but no data are available on its predictive value in patients on DAPT after carotid artery stenting (CAS). We aimed to evaluate the possible association between HTPR in patients on aspirin plus clopidogrel therapy after CAS and subsequent MACE.

Methods: All consecutive patients treated with CAS in a single institution were enrolled in a prospective clinical study.

Fungal communities in European alpine soils are not affected by short-term in situ simulated warming than bacterial communities.

The impact of global warming on biological communities colonizing European alpine ecosystems was recently studied. Hexagonal open top chambers (OTCs) were used for simulating a short-term in situ warming (estimated around 1°C) in some alpine soils to predict the impact of ongoing climate change on resident microbial communities. Total microbial DNA was extracted from soils collected either inside or outside the OTCs over 3 years of study.

Anti-severe acute respiratory syndrome coronavirus-2 adenoviral-vector vaccines trigger subclinical antiplatelet autoimmunity and increase of soluble platelet activation markers.

To slow down the coronavirus disease 2019 (COVID-19) pandemic an unequalled vaccination campaign was initiated. Despite proven efficacy and safety, a rare but potentially fatal complication of adenoviral-vector vaccines, called vaccine-induced immune thrombotic thrombocytopenia (VITT), has emerged the pathogenesis of which seems to be related to the development of platelet-activating anti-platelet factor 4 (PF4) antibodies. While a few studies have evaluated the incidence of anti-PF4 positivity in anti-severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccine recipients, to date no studies have assessed whether an antiplatelet immunological response develops and if this associates with platelet and blood clotting activation.

A p.Arg127Gln variant in GPIbα LRR5 allosterically enhances affinity for VWF: a novel form of platelet-type VWD.

Gain-of-function (GOF) variants in GP1BA cause platelet-type von Willebrand disease (PT-VWD), a rare inherited autosomal dominant bleeding disorder characterized by enhanced platelet GPIbα to von Willebrand factor (VWF) interaction, and thrombocytopenia. To date, only 6 variants causing PT-VWD have been described, 5 in the C-terminal disulfide loop of the VWF-binding domain of GPIbα and 1 in the macroglycopeptide. GOF GP1BA variants generate a high-affinity conformation of the C-terminal disulfide loop with a consequent allosteric conformational change on another region of GPIbα, the leucine-rich-repeat (LRR) domain.

Platelet dysfunction in platelet-type von Willebrand disease due to the constitutive triggering of the Lyn-PECAM1 inhibitory pathway.

Platelet-type von Willebrand disease (PT-VWD) is an inherited platelet disorder. It is characterized by macrothrombocytopenia and mucocutaneous bleeding, of variable severity, due to gain-of-function variants of GP1BA conferring to glycoprotein Ibα (GPIbα) enhanced affinity for von Willebrand factor (VWF). The bleeding tendency is conventionally attributed to thrombocytopenia and large VWF-multimer depletion.

Endolithic Bacterial Diversity in Lichen-Dominated Communities Is Shaped by Sun Exposure in McMurdo Dry Valleys, Antarctica.

The diversity and composition of endolithic bacterial diversity of several locations in McMurdo Dry Valleys (Continental Antarctica) were explored using amplicon sequencing, targeting the V3 and V4 of the 16S region. Despite the increasing interest in edaphic factors that drive bacterial community composition in Antarctic rocky communities, few researchers focused attention on the direct effects of sun exposure on bacterial diversity; we herein reported significant differences in the northern and southern communities. The analysis of β-diversity showed significant differences among sampled localities.

Effect of First Long-Term Training on Whole Blood Count and Blood Clotting Parameters in Thoroughbreds.

Training has a strong effect on the physiology of hematological parameters and blood coagulation, both in humans and in horses. Several blood changes have been reported after exercise in horses but available data differ. We aimed to investigate modifications in complete blood count and some hemostatic parameters induced by the first training period in young untrained Thoroughbred racehorses to detect a possible labile blood coagulability in racehorses.

sp. nov. and sp. nov., two novel basidiomycetous yeast species isolated from cold environments.

Five yeast strains were isolated from soil and sediments collected from Alps and Apennines glaciers during sampling campaigns carried out in summer 2007 and 2017, respectively. Based on morphological and physiological tests and on phylogenetic analyses reconstructed with ITS and D1/D2 sequences, the five strains were considered to belong to two related but hitherto unknown species within the genus , in an intermediate position between and . The names (holotype DBVPG 10734) and (holotype DBVPG 10736) are proposed for the two novel species and a detailed description of their morphological, physiological and phylogenetic features are presented.

Intra- and inter-cores fungal diversity suggests interconnection of different habitats in an Antarctic frozen lake (Boulder Clay, Northern Victoria Land).

A perennially frozen lake at Boulder Clay site (Victoria Land, Antarctica), characterized by the presence of frost mounds, have been selected as an in situ model for ecological studies. Different samples of permafrost, glacier ice and brines have been studied as a unique habitat system. An additional sample of brines (collected in another frozen lake close to the previous one) was also considered.

FVIII/VWF complex displays a greater pro-haemostatic activity than FVIII preparations devoid of VWF: Study in plasma and cell-based models.

Introduction: Plasma-derived FVIII/VWF complex was reported to be less sensitive to inhibitors than FVIII preparations devoid of VWF.

Aim: To compare the efficacy of FVIII/VWF complex (Fanhdi) and five different VWF-free FVIII preparations in restoring thrombin generation and activation of thrombin-activatable fibrinolysis inhibitor (TAFI) in haemophilic plasma, with and without inhibitor, and in cell-based models.

Methods: Experiments were performed in haemophilic plasma supplemented with inhibitory IgG or in plasma samples obtained from haemophilia A patients without (n = 11) and with inhibitor (n = 12).

Inhibition of platelet function after ocular administration of non-steroidal anti-inflammatory drugs.

Introduction: The use of topical NSAIDs is frequent in ophthalmology to reduce the local inflammatory reaction resulting from surgical procedures. Ocular use of some drugs was previously found to lead to significant systemic absorption with possible systemic effects. NSAIDs may enhance the hemorrhagic risk of anticoagulant and antiplatelet drugs.

Platelet function assays in diagnosis: an update.

Hemorrhagic diseases associated with platelet dysfunction include inherited platelet function disorders (IPFD) and a large number of non-hereditary conditions, defined as acquired platelet function disorders (APFD). Their identification requires a careful clinical evaluation and a rational use of diagnostic laboratory assays. Areas covered: Here we describe the laboratory techniques currently available for the assessment of platelet function, including new and experimental laboratory assays, and their alterations in platelet function disorders.

Effect of aspirin treatment on abacavir-associated platelet hyperreactivity in HIV-infected patients.

Background: Ischemic cardiovascular events are a relevant cause of morbidity and mortality in HIV-infected patients. Use of abacavir (ABC), a nucleoside analog reverse transcriptase inhibitor, has been associated with increased risk of myocardial infarction (MI) and with platelet hyperreactivity. We explored whether low-dose aspirin reduces in vivo platelet activation and platelet hyperreactivity induced by ABC in HIV-infected subjects.

Prevalence of hemostatic alterations in patients with recurrent spontaneous subconjunctival hemorrhage.

Background: Subconjunctival hemorrage (SCH) is a frequent, mild bleeding manifestation and a common cause of consultation. Hemostatic alterations are possible causes of SCH but their role and prevalence is unknown. We assessed the prevalence of hemostatic abnormalities in patients with spontaneous, recurrent SCH to clarify the role of the hemostasis laboratory in this clinical setting.

Analysis of 339 pregnancies in 181 women with 13 different forms of inherited thrombocytopenia.

Pregnancy in women with inherited thrombocytopenias is a major matter of concern as both the mothers and the newborns are potentially at risk of bleeding. However, medical management of this condition cannot be based on evidence because of the lack of consistent information in the literature. To advance knowledge on this matter, we performed a multicentric, retrospective study evaluating 339 pregnancies in 181 women with 13 different forms of inherited thrombocytopenia.

In vivo platelet activation and platelet hyperreactivity in abacavir-treated HIV-infected patients.

Abacavir (ABC) has been associated with ischaemic cardiovascular events in HIV-infected patients, but the pathogenic mechanisms are unknown. Aim of our study was to assess whether ABC induces in vivo platelet activation and ex vivo platelet hyper-reactivity. In a retrospective, case-control study, in vivo platelet activation markers were measured in 69 HIV-infected patients, before starting therapy and after 6-12 months of either ABC (n=35) or tenofovir (TDF) (n=34), and compared with those from 20 untreated HIV-infected patients.

Platelet size for distinguishing between inherited thrombocytopenias and immune thrombocytopenia: a multicentric, real life study.

The most frequent forms of inherited thrombocytopenia (IT) are characterized by platelet size abnormalities and it has been suggested that this parameter is useful for their differentiation from immune thrombocytopenia (ITP). Recently, a monocentric study identified cut-off values for mean platelet volume (MPV) and mean platelet diameter (MPD) with good diagnostic accuracy in this respect. To validate these cut-off values in a different and larger case series of patients, we enrolled 130 subjects with ITP and 113 with IT in six different centres.