Search results for "platelets"
showing 10 items of 218 documents
Effect of processing temperature and mixing time on the properties of PP/GnP nanocomposites
2020
Abstract During processing of molten polymers the thermal and mechanical stress acting on the melt in presence of oxygen can induce degradation with a modification of the chemical structure of the polymers. This picture can become even more relevant if the melt is a multiphasic polymer system. In this last case, the effects of the degradation depend also on the presence of a second phase and on the interactions between the two phases. In this work, the effect of the processing conditions, temperature and time, have been considered in order to investigate the thermo-mechanical and thermo-oxidative degradation of nanocomposites made by polypropylene and different contents of graphene nanoplat…
Photo-oxidation of polypropylene/graphene nanoplatelets composites
2019
Abstract The photo-oxidation behaviour of polymer nanocomposites depends not only on the photo-oxidation behaviour of the matrix, but also on the chemical composition, on the physical properties of the nanoparticles and on the possible interactions between the two phases. In the case of nanocomposites with carbonaceous particles, the main effect is a photo-stabilization due to the absorption of the UV energy and the radical scavenging action. In this work we investigated the effect of the presence of graphene nanoplatelets on the photo-oxidation behaviour of the polypropylene. The presence of the graphene nanoplatelets improves the photo-resistance of the polypropylene and this effect incre…
Role of hematopoietic cells in Mycobacterium tuberculosis infection.
2021
Tuberculosis remains one of the most significant causes of mortality worldwide and the current situation shows a re-emergence of TB due to the emergence of new antibiotic-resistant strains and the widespread of disease caused by immunodeficiencies. For these reasons, a big effort is made to improve the therapeutic strategies against Mycobacterium tuberculosis and to perform new therapeutic and diagnostic strategies. This review analyzes the various hematopoietic populations, their role and the different changes they undergo during Mycobacterium tuberculosis infection or disease. We have examined the population of lymphocytes, monocytes, neutrophils, eosinophils and platelets, in orderto und…
In vivo effects of intravascularly applied Escherichia coli hemolysin: dissociation between induction of granulocytopenia and lethality in monkeys.
1993
The effects of intravascular application of endotoxin-depleted Escherichia coli hemolysin (HlyA) was studied in rabbits and monkeys. In rabbits, bolus application of HlyA calculated to effect final blood levels of approximately 2-3 HU/ml (200-300 ng/ml) caused an acute fall of polymorphonuclear blood leukocytes to less than 20% of starting levels within 5 min. Additionally, platelet counts dropped to approximately 30% of starting levels, whereas lymphocyte counts varied considerably and seldom fell to less than 50%. Nine out ten animals that received 2-4 HU/ml toxin died within 90 min post application. These animals presented with signs of acute respiratory failure and post mortem inspectio…
Performances and morphology of polyamide/carbonaceous structures based fibers
2014
In this work the influence of carbonaceous particles with different particle sizes and shapes on the morphology and mechanical performances of polyamide (PA) based fibers was investigated. Graphene nanoplatelets (GNP) are compared with spherical and rod-like carbon fillers such as carbon black (CB) and multiwall carbon nanotubes (MWCNT). The different morphologies of the particles control their dispersion and their alignment in PA fibers upon elongational flow action and play a key role in structure-property relationships.
Thermomechanical degradation of PP based nanocomposites filled with graphene nanoplatelets
2018
Graphitic nanofillers have extensively used to prepare nanocomposites based on both conventional petroleum based plastics and bio-based polymers . Among them, graphene or graphite nanoplatelets (GnP), also called graphite nanosheets or nanoflakes, are a relatively new carbon nanomaterial composed of stacked 2D graphene sheets with outstanding electrical, thermal and mechanical properties. Indeed, by adding GnP, also at low filler concentration (< 5 wt.%), the mechanical, heat-resistance, thermal and electrical properties of the polymer matrix can surprisingly enhance due to unique properties of these nanofillers. However, the characteristics of these multiphase systems certainly depend o…
New pathways of increased cardiovascular risk in depression: a pilot study on the association of high-sensitivity C-reactive protein with pro-atheros…
2013
Abstract Background An elevation of inflammatory markers such as high-sensitivity C-reactive protein (hs-CRP) can be found in patients with depressive disorders. Inflammatory processes are known to influence atherosclerosis and might also mediate the link between depression and diabetes. The present study aimed at comparing hs-CRP and its relationship with atherogenic platelet markers in patients with type 2 diabetes (TD2) and/or newly diagnosed major depression (MD). Methods Hs-CRP concentrations in 24 patients with TD2, 21 patients with MD (diagnosed according to ICD-10 and DSM-IV), 19 patients with TD2 and comorbid MD, and 25 healthy controls were compared using analysis of variance. The…
Thrombin generation - a potentially useful biomarker of thrombotic risk in Philadelphia-negative myeloproliferative neoplasms.
2017
The diagnosis of essential thrombocythemia and polycythemia vera is often made during a thrombotic event which can be serious. Philadelphia-negative chronic myeloproliferative neoplasia patients have an increased thrombotic risk. This is assessed using various scoring systems but these are far from ideal and individual risk. The currend trend to personalised medicine requires finding the most useful thrombotic risk biomarker in these patients. Routine tests for coagulation do not take account of both pro- and anti-coagulant factors which is why these tests are not useful in patients with Philadelphia-negative myeloproliferative neoplasms. Thrombin generation reflects more accurately the bal…
Systemic Inflammatory Markers and Oncologic Outcomes in Patients with High-risk Non-muscle-invasive Urothelial Bladder Cancer
2018
Background: Serum levels of neutrophils, platelets, and lymphocytes have been recognized as factors related to poor prognosis for many solid tumors, including bladder cancer (BC). Objective: To evaluate the prognostic role of the combination of the neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and lymphocyte/monocyte ratio (LMR) in patients with high-risk non–muscle-invasive urothelial BC (NIMBC). Design, setting, and participants: A total of 1151 NMIBC patients who underwent first transurethral resection of the bladder tumor (TURBT) at 13 academic institutions between January 1, 2002 and December 31, 2012 were included in this analysis. The median follow-up was 48 mo.…
Clinical Applications, Pitfalls, and Uncertainties of Thrombin Generation in the Presence of Platelets
2019
Platelet-dependent thrombin generation is a helpful tool to assess ex vivo the interaction between platelets and plasma coagulation factors in the initiation, amplification, and inhibition of thrombin generation (TG). This review article discusses the most relevant available data on the clinical applications of fluorogenic TG, the most widely used TG assay, performed in the presence of platelets, i.e., in platelet-rich plasma. With respect to prothrombotic states, arterial hypertension and obesity were the most prominent cardiovascular conditions linked to increased platelet-dependent TG. In addition, platelet-associated hypercoagulability, assessed by the TG assay, has been shown in indivi…