Content Of Microparticles Research Articles

Synthesis of Phenanthrene/Pyrene Hybrid Microparticles: Useful Synthetic Mimics for Polycyclic Aromatic Hydrocarbon-Based Cosmic Dust.

Polycyclic aromatic hydrocarbons (PAHs) are found throughout the interstellar medium and are important markers for the evolution of galaxies and both star and planet formation. They are also widely regarded as a major source of carbon, which has implications in the search for extraterrestrial life. Herein we construct a melting point phase diagram for a series of phenanthrene/pyrene binary mixtures to identify the eutectic composition (75 mol % phenanthrene) and its melting point (83 °C). The molten oil obtained on heating this eutectic composition to 90 °C in aqueous solution is homogenized in the presence of a water-soluble polymeric emulsifier. On cooling to 20 °C, polydisperse spherical phenanthrene/pyrene hybrid microparticles are obtained. Varying the stirring rate and emulsifier type enables the mean microparticle diameter to be adjusted from 11 to 279 μm. Importantly, the phenanthrene content of individual microparticles remains constant during processing, as expected for the eutectic composition. These new hybrid microparticles form impact craters and undergo partial fragmentation when fired into a metal target at 1 km s-1 using a light gas gun. When fired into an aerogel target at the same speed, microparticles are located at the ends of characteristic "carrot tracks". Autofluorescence is observed in both types of experiments, which at first sight suggests minimal degradation. However, Raman microscopy analysis of the aerogel-captured microparticles indicates prominent pyrene signals but no trace of the more volatile phenanthrene component. Such differential ablation during aerogel capture is expected to inform the in situ analysis of PAH-rich cosmic dust in future space missions.

Composite Paints with High Content of Metallic Microparticles for Electromagnetic Shielding Purposes

This paper describes the technological process used to manufacture composite paints with a high content of metallic microparticles (Al and Fe) for automotive electromagnetic compatibility applications. The thickness of the deposited paint layer was larger for paints with a greater metal content, regardless of the plastic support used for paint deposition. The roughness of paint layers with a greater content of metal particles was about 30%–35% higher than that of layers with a lower metal particle content, regardless of the metal type. The surface roughness of paint layers containing Al was at least 2.5-times higher than that of paint layers containing Fe, an aspect that could be explained by the better formulation of the paint containing Fe. The dielectric loss and conductivity values crucially depend on the plastic substrate used, meaning that the dipolar polarization of the substrate enhances the effect of conductive paints. Based on the dielectric properties measured at 10 kHz, the optimal recipe for efficient electromagnetic compatibility was found to be 20 wt.% Fe powder, deposited on a sandblasted polycarbonate (PC) substrate. It is expected that formulations of paints with a high percentage of metallic particles will effectively compete with traditional plastic metallization technologies.

Attenuation properties of poly methyl methacrylate reinforced with micro/nano ZrO2 as gamma-ray shields

This research aimed to examine the radiation shielding properties of unique polymer composites for medical and non-medical applications. For this purpose, polymer composites, based on poly methyl methacrylate (PMMA) as a matrix, were prepared and reinforced with micro- and nanoparticles of ZrO2 fillers at a loading of 15%, 30%, and 45% by weight. Using the high purity germanium (HPGe) detector, the suggested polymer composites’ shielding characteristics were assessed for various radioactive sources. The experimental values of the mass attenuation coefficients (MAC) of the produced composites agreed closely with those obtained theoretically from the XCOM database. Different shielding parameters were estimated at a broad range of photon energies, including the linear attenuation coefficient (μ), tenth value layer (TVL), half value layer (HVL), mean free path (MFP), effective electron density (Neff), effective atomic number (Zeff), and equivalent atomic number (Zeq), as well as exposure buildup factor (EBF) and energy absorption buildup factor (EABF) to provide more shielding information about the penetration of γ-rays into the chosen composites. The results showed that increasing the content of micro and nano ZrO2 particles in the PMMA matrix increases μ values and decreases HVL, TVL, and MFP values. P-45nZ sample with 45 wt% of ZrO2 nanoparticles had the highest μ values, which varied between 2.6546 and 0.0991 cm−1 as γ-ray photon energy increased from 0.0595 to 1.408 MeV, respectively. Furthermore, the highest relative increase rate in μ values between nano and micro composites was 17.84%, achieved for the P-45nZ sample at 59.53 keV. These findings demonstrated that ZrO2 nanoparticles shield radiation more effectively than micro ZrO2 even at the same photon energy and filler wt%. Thus, the proposed nano ZrO2/PMMA composites can be used as effective shielding materials to lessen the transmitted radiation dose in radiation facilities.

Preparation, physicochemical characterization and swelling properties of composite hydrogel microparticles based on gelatin and pectins with different structure

Composite hydrogel microparticles based on pectins with different structures (callus culture pectin (SVC) and apple pectin (AU)) and gelatin were developed. Hydrogel microparticles were formed by the ionotropic gelation and electrostatic interaction of COO− groups of pectin and NH3+ groups of gelatin, which was confirmed by FTIR spectroscopy. The addition of gelatin to pectin-based gel formulations resulted in a decrease in gel strength, whereas increasing gelatin concentration enhanced this effect. The microparticle gel strength increased in proportion to the increase in the pectin concentration. The DSC and TGA analyzes showed that pectin-gelatin gels had the higher thermal stability than individual pectins. The gel strength, Ca2+ content and thermal stability of the microparticles based on gelatin and SVC pectin with a lower degree of methylesterification (DM) (14.8 %) were higher compared to that of microparticles based on gelatin and AU pectin with a higher DM (40 %). An increase in the SVC concentration, Ca2+ content and gel strength of SVC-gelatin microparticles led to a decrease in the swelling degree in simulated gastrointestinal fluids. The addition of 0.5 % gelatin to gels based on AU pectin resulted in increased stability of the microparticles in gastrointestinal fluids, while the microparticles from AU without gelatin were destroyed.

Coagulation in Patients with Immune Thrombocytopenia and Other Associated Autoimmune Disorders

Introduction Chronic immune thrombocytopenia (ITP) is characterized by perturbations of immune homeostasis with hyperactivated effector cells as well as defective regulation of the adaptive immune system. It has been reported that, with varying frequency, patients with ITP may also have associated other autoimmune disorders, with circulating autoantibodies such as lupus anticoagulant antibodies (LACs), anti-nuclear antibodies (ANA), anticardiolipin (aCL), anti-beta2-glycoprotein I (anti-beta2GPI), anti-thyroid peroxidase (ATPA), and rheumatoid factor (RF). Objectives To evaluate coagulation in patients with ITP with autoantibodies associated to other autoimmune diseases. Methods This is a prospective study that was approved by the Ethics Committee from Hospital Universitario La Paz. Informed consent was signed before sampling. Adult ITP patients (n=182) without and with associated autoantibodies such as LACs, ANA, aCL, anti-beta2GPI, ATPA, and RF and healthy controls (n=180) were recruited. To evaluate the kinetics of clot formation and fibrinolysis, ROTEM® was performed on fresh platelet rich plasma adjusted to 25x10 9 platelets/L with the subjects own platelet poor plasma (PPP). Recalcification (NATEM) was used to induce coagulation. Clotting time (CT = time from start of measurement until initiation of clotting, in seconds); alpha angle (tangent to the curve at 2 mm amplitude, in degrees, which reflects the rate of fibrin polymerization); maximum clot firmness (MCF = maximum clot firmness, in mm, which reflects the maximum tensile strength of the thrombus); and lysis at 60 min (LI60) were recorded. Thrombin generation was measured in citrated PPP by calibrated automated thrombogram (CAT). To evaluate procoagulant capacity of plasma, coagulation was triggered by proper recalcification and the addition (final concentrations) of 1 pmol/L of recombinant human tissue factor (TF) and 4 µmol/L of phospholipid mixture (PPP-Reagent LOW, Thrombinoscope BV, Maastricht, The Netherlands). Procoagulant activity of microparticles (MPs) associated with their content of either TF or phosphatidylserine (PS) was determined, respectively, with MP reagent (4 µM phospholipids) or PRP reagent (1 pM of recombinant human TF) by CAT. The following parameters were determined: Lag time (LT), or time from the start of the assay until 10 nM thrombin is formed, in min; time-to-peak (ttPeak), or time required to reach the maximum thrombin concentration, in min; peak height (Peak), or maximum thrombin concentration reached, in nM; and endogenous thrombin potential (ETP), or total amount of thrombin generated over time, in nMxmin. Results Fifty of the 182 patients with ITP (27.5%) were positive for autoantibodies associated with other autoimmune diseases, distributed as shown in Table 1. ANA were the most frequent antibodies present in these patients, and 22% had more than one kind of associated antibodies. Patients with ITP without antibodies had a shorter clot formation time (CT) than healthy controls. Presence of associated autoimmune diseases prolongs CT and resulting in values similar to controls. Both groups of patients with ITP had a diminished fibrinolysis (Table 2). Thrombin generation triggered by TF plus phospholipids as well as that dependent on TF content of microparticles (MP-reagent) was impaired in patients with other associated autoimmune disorders as shown by the prolonged LT and the diminution in either ETP or peak of generated thrombin (Table 2). When thrombin generation relayed on phospholipids of MPs, all patients with ITP generated less thrombin. Conclusion Association of other autoimmune diseases with ITP seemed to produce a delay in clot formation and in thrombin generation whereas did not affect the diminished fibrinolysis observed in ITP patients. Work supported by Instituto de Salud Carlos III (ISCIII) (PI19/00772, PI22/01489), co-funded by the European Union.

Research and Assessment of the Possibility of Biodegradation of PVD, HDPE by Larvae Galleria Mellonella (Lepidoptera, INSECTA)

Comparative analysis performed on morphometric parameters of Galleria mellonella larvae grown on natural nutrient media with the addition of LDPE (low density polyethylene), HDPE (high density polyethylene) in various ratios 50/50, 60/40, 70/30, 80/20, 90/10. Levelling of different ratios of polymers was revealed while maintaining the viability of larvae. The content of LDPE microparticles in roughages of the digestive tract of larvae was identified by Fourier transform infrared spectroscopy showing partial digestion of synthetic polymers.

Introduction of reinforcing microparticles of TiB2 and BN into aluminium by electromagnetic stirring

The paper describes an experiment in which aluminum alloy was reinforced with TiB2 and BN particles and investigates the physical properties of the resulting aluminum composite. In the experiment, TiB2 and BN reinforcing particles were introduced into molten metal as part of pellets produced from aluminum micro powder in the presence of MHD mixing with subsequent directional crystallization. The pellets were thrown into a crucible with liquid aluminum placed in the working volume of an MHD stirrer, which generated separately controlled toroidal and poloidal flows. It was found that the dissolution of the pellets prepared from the mixture of aluminum micro particles (100–150 μm) and reinforcing TiB2 micro particles (1–5 μm) under MHD stirring proceeds much better compared to the pellets with BN micro particles (1–5 μm). The pellets in which the weight percentage of BN reinforcing particles exceeds 7% poorly “dissolve” in aluminum melt, while the pellets with 10% TiB2 micro particles “dissolve” satisfactorily. Due to a large number of pellets introduced into liquid aluminum in the course of the experiment and because of the strong cooling of the melt, it was not possible to obtain the weight percentage of reinforcing micro particles in an aluminum ingot exceeding 2.5% for TiB2 micro particles and 1.4% for BN micro particles. The results of the experiment showed that the hardness and tensile strength of aluminum increase with increasing content of TiB2 and BN micro particles in a similar way, but in the case BN particles to a lesser extent. The strength and electrical resistivity of liquid aluminum reinforced with TiB2 and BN particles increase with their rising fraction.The structural study of the specimens on electron and digital optical microscopes were carried out in compliance with the state budget subject AAAAA19-119012290101-5 of the Institute of Continuum Mechanics at the UralBranch of the Russian Academy of Sciences; the experiments on introduction of microparticles into molten aluminium were funded by the Government of the Perm Kray and the Russian Foundation for Basic Research under the Ural regional project No. [19-48-590001 р_а].

Circulating Microparticles Are Differentially Increased in Lowlanders and Highlanders with High Altitude Induced Pulmonary Hypertension during the Cold Season.

The role of microparticles (MPs) and cold in high altitude pulmonary hypertension (HAPH) remains unexplored. We investigated the impact of long-term cold exposure on the pulmonary circulation in lowlanders and high-altitude natives and the role of MPs. Pulmonary hemodynamics were evaluated using Doppler echocardiography at the end of the colder and warmer seasons. We further examined the miRNA content of MPs isolated from the study participants and studied their effects on human pulmonary artery smooth muscle (hPASMCs) and endothelial cells (hPAECs). Long-term exposure to cold environment was associated with an enhanced pulmonary artery pressure in highlanders. Plasma levels of CD62E-positive and CD68-positive MPs increased in response to cold in lowlanders and HAPH highlanders. The miRNA-210 expression contained in MPs differentially changed in response to cold in lowlanders and highlanders. MPs isolated from lowlanders and highlanders increased proliferation and reduced apoptosis of hPASMCs. Further, MPs isolated from warm-exposed HAPH highlanders and cold-exposed highlanders exerted the most pronounced effects on VEGF expression in hPAECs. We demonstrated that prolonged exposure to cold is associated with elevated pulmonary artery pressures, which are most pronounced in high-altitude residents. Further, the numbers of circulating MPs are differentially increased in lowlanders and HAPH highlanders during the colder season.

Tailoring the physicochemical properties of freeze-dried buriti oil microparticles by combining inulin and gum Arabic as encapsulation agents

Buriti (Mauritia flexuosa) oil, native from the Amazon region, is a natural compound with several antioxidant properties and high carotene content. This oil can be used for cosmetic and dietary purposes. Considering the industrial importance of this oil, it is proposed a new high-tech product consisting in buriti oil microparticles. In this sense, the effect of biopolymers (inulin and gum arabic) on the physicochemical properties of freeze-dried buriti oil microparticles was evaluated in different combinations. The increase of inulin addition significantly increased (p ˂ 0.05) the Aw values and the moisture content of microparticles. Negative zeta potential near −30 mV was observed for all treatments indicating stability. The polydispersity index (PI) ranged from 0.14 to 0.37. The wettability found ranged from 59 s to 71 s, considered optimal for powdered foods for industry and consumer market requirements. Equal amount of wall material showed higher solubility value. The diffractograms showed that the incorporation of buriti oil in the microparticles does not significantly change the amorphous character already observed in the isolated materials. Hence, the combination in equivalent proportions of inulin and gum Arabic is a viable alternative for application of freeze-dried buriti oil microparticles in foods that present hydrophilic character.

Angiogenic content of microparticles in patients with diabetes and coronary artery disease predicts networks of endothelial dysfunction

BackgroundElevated endothelial microparticles (EMPs) levels are surrogate markers of vascular dysfunction. We analyzed EMPs with apoptotic characteristics and assessed the angiogenic contents of microparticles in the blood of patients with type 2 diabetes (T2D) according to the presence of coronary artery disease (CAD).MethodsA total of 80 participants were recruited and equally classified as (1) healthy without T2D, (2) T2D without cardiovascular complications, (3) T2D and chronic coronary artery disease (CAD), and (4) T2D and acute coronary syndrome (ACS). MPs were isolated from the peripheral circulation, and EMPs were characterized using flow cytometry of CD42 and CD31. CD62E was used to determine EMPs’ apoptotic/activation state. MPs content was extracted and profiled using an angiogenesis array.ResultsLevels of CD42- CD31 + EMPs were significantly increased in T2D with ACS (257.5 ± 35.58) when compared to healthy subjects (105.7 ± 12.96, p < 0.01). There was no significant difference when comparing T2D with and without chronic CAD. The ratio of CD42-CD62 +/CD42-CD31 + EMPs was reduced in all T2D patients, with further reduction in ACS when compared to chronic CAD, reflecting a release by apoptotic endothelial cells. The angiogenic content of the full population of MPs was analyzed. It revealed a significant differential expression of 5 factors in patients with ACS and diabetes, including TGF-β1, PD-ECGF, platelet factor 4, serpin E1, and thrombospondin 1. Ingenuity Pathway Analysis revealed that those five differentially expressed molecules, mainly TGF-β1, inhibit key pathways involved in normal endothelial function. Further comparison of the three diabetes groups to healthy controls and diabetes without cardiovascular disease to diabetes with CAD identified networks that inhibit normal endothelial cell function. Interestingly, DDP-IV was the only differentially expressed protein between chronic CAD and ACS in patients with diabetes.ConclusionOur data showed that the release of apoptosis-induced EMPs is increased in diabetes, irrespective of CAD, ACS patients having the highest levels. The protein contents of MPs interact in networks that indicate vascular dysfunction.

Effect of the icariin on endothelial microparticles, endothelial progenitor cells, platelets, and erectile function in spontaneously hypertensive rats.

To investigate the effect of icariin on endothelial microparticles, endothelial progenitor cells, platelets, and erectile function in spontaneously hypertensive rats. Twelve 8-week-old healthy male Wistar-Kyoto rats and 12 spontaneously hypertensive rats were randomly divided into four following groups: Wistar-Kyoto control group (normal saline 1ml/d given by gavage), Wistar-Kyoto + icariin group (icariin 10mg/kg × d dissolved in 1ml normal saline and given by gavage), spontaneously hypertensive rats control group (normal saline 1ml/d given by gavage), and spontaneously hypertensive rats + icariin group (icariin 10mg/kg × d dissolved in 1ml normal saline and given by gavage). Four weeks later, the maximum intracavernous pressure/mean arterial pressure, platelet count, mean platelet volume, platelet distribution width, endothelial microparticles, endothelial progenitor cells, and vitronectin receptor were measured in each group. Under 3 or 5 V electrical stimulation, the maximum intracavernous pressure/mean arterial pressure in the spontaneously hypertensive rats + icariin group (0.23 ± 0.03, 0.38 ± 0.02) was significantly higher compared to the spontaneously hypertensive rats control group (0.12 ± 0.02, 0.20 ± 0.02) (p<0.05). Platelet count, mean platelet volume, and platelet distribution width in the spontaneously hypertensive rats + icariin group (1103.67 ± 107.70 × 109 /L, 9.08 ± 0.50 fl, 11.87 ± 0.45%) were significantly lower than those in the spontaneously hypertensive rats control group (1298.00 ± 89.54 × 109 /L, 9.72 ± 0.44 fl, 13.03 ± 0.59%) (all p<0.05). Endothelial microparticles, endothelial progenitor cells, and vitronectin receptor in the spontaneously hypertensive rats + icariin group (1.01 ± 0.28%, 1.53 ± 0.65%, 2.13 ± 0.53%) were significantly lower than those in the spontaneously hypertensive rats control group (1.58 ± 0.19%, 2.71 ± 0.64%, 3.76 ± 0.52%) (all p<0.05). Moreover, maximum intracavernous pressure/mean arterial pressure was strongly negatively correlated with platelet distribution width and vitronectin receptor (r>0.7), and maximum intracavernous pressure/mean arterial pressure was moderately negatively correlated with mean platelet volume, endothelial microparticles, and endothelial progenitor cells (0.5<r<0.7). Icariin may improve erectile function in spontaneously hypertensive rats by reducing the content of endothelial microparticles in blood and inhibiting the activation of the platelets. Endothelial microparticles, endothelial progenitor cells, and platelet activation-related (mean platelet volume, platelet distribution width, and vitronectin receptor) can be used as indicators for icariin to improve erectile function in spontaneously hypertensive rats.

Vascular damage effect of circulating microparticles inpatients with ACS is aggravated by type2 diabetes.

As a common factor of both type 2 diabetes mellitus (T2DM) and acute coronary syndrome (ACS), circulating microparticles (MPs) may provide a link between these two diseases. The present study compared the content and function of MPs from patients with ACS with or without T2DM. MPs from healthy subjects (n=20), patients with ACS (n=24), patients with T2DM (n=20) and patients with combined ACS and T2DM (n=24) were obtained. After incubating rat thoracic tissue with MPs, the effect of MPs on endothelial-dependent vasodilatation, expression of caveolin-1 and endothelial nitric oxide synthase (eNOS), phosphorylation of eNOS at the S1177 and T495 sites and its association with heat shock protein 90 (Hsp90), and the generation of NO and superoxide anion (O2˙-) were determined. MP concentrations were higher in patients with T2DM and patients with ACS with or without T2DM than in healthy subjects. Moreover, MPs from patients with T2DM or ACS led to impairment in endothelial-dependent vasodilatation, decreased expression of NO, as well as eNOS and its phosphorylation at Ser1177 and association with Hsp90, but increased eNOS phosphorylation at T495, caveolin-1 expression and O2˙- generation. These effects were strengthened by MPs from patients with ACS combined with T2DM. T2DM not only increased MP content but also resulted in greater vascular impairment effects in ACS. These results may provide novel insight into the treatment of patients with ACS and T2DM.

Influence of micro Ti particles on resistance to cavitation erosion of Mg-xTi composites

Magnesium-titanium composites with different content of titanium micro particles were produced using disintegrated melt deposition (DMD) technique. The measurements of porosity and hardness as well as cavitation erosion resistance of Mg-xTi composites were performed. In order to detect phase composition, X-ray diffraction studies were performed. In all composites, α-Mg and α -Ti phases were detected and no interfacial reactions between the matrix and reinforcement were observed. Porosity of the composites increased with increasing content of Ti particles. The lowest porosity was observed in Mg-2.5Ti composite, while the highest in Mg–15Ti composite. While all composites underwent strain-hardening comparable to that of pure Mg after 5 min of cavitation erosion testing, the best cavitation resistance was demonstrated by Mg-2.5Ti composite, while the lowest was demonstrated by Mg–15Ti composite. Degradation of Mg-xTi composites occurred as a result of the development of cracks at the interface between Ti particles and Mg matrix.

A Novel Pool of Microparticle Cholesterol Is Elevated in Rheumatoid Arthritis but Not in Systemic Lupus Erythematosus Patients

Microparticles are sub-micron, membrane-bound particles released from virtually all cells and which are present in the circulation. In several autoimmune disorders their amount and composition in the circulation is altered. Microparticle surface protein expression has been explored as a differentiating tool in autoimmune disorders where the clinical pictures can overlap. Here, we examine the utility of a novel lipid-based marker—microparticle cholesterol, present in all microparticles regardless of cellular origin—to distinguish between rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). We first isolated a series of microparticle containing lipoprotein deficient fractions from patient and control plasma. There were no significant differences in the size, structure or protein content of microparticles isolated from each group. Compared to controls, both patient groups contained significantly greater amounts of platelet and endothelial cell-derived microparticles. The cholesterol content of microparticle fractions isolated from RA patients was significantly greater than those from either SLE patients or healthy controls. Our data indicate that circulating non-lipoprotein microparticle cholesterol, which may account for 1–2% of measured cholesterol in patient samples, may represent a novel differentiator of disease, which is independent of cellular origin.

Insights into the Procoagulant Profile of Patients with Systemic Lupus Erythematosus without Antiphospholipid Antibodies.

We aimed to identify the key players in the prothrombotic profile of patients with systemic lupus erythematosus (SLE) not mediated by antiphospholipid antibodies, as well as the potential utility of global coagulation tests to characterize hemostasis in these patients. Patients with SLE without antiphospholipid antibodies and without signs of thrombosis were included. The kinetics of clot formation were determined by ROTEM®. Platelet activation markers were determined by flow cytometry. Thrombin generation associated with Neutrophil Extracellular Traps (NETs) and microparticles (MPs) was measured by calibrated automated thrombogram (CAT). The plasma levels of PAI-1 were also determined. ROTEM® showed a procoagulant profile in SLE patients. SLE patients had activated platelets and more leukocyte/platelet aggregates at basal conditions. The plasma PAI-1 and platelet aggregates correlated with several ROTEM® parameters. The thrombin generation associated withthe tissue factor (TF) content of MPs and with NETs was increased. Our results suggest the utility of global tests for studying hemostasis in SLE patients because they detect their procoagulant profile, despite having had neither antiphospholipid antibodies nor any previous thrombotic event. A global appraisal of hemostasis should, if possible, be incorporated into clinical practice to detect the risk of a thrombotic event in patients with SLE and to consequently act to prevent its occurrence.

Non-silicate nanoparticles for improved nanohybrid resin composites

ObjectiveZirconia and alumina nanoparticles were coated with a silica-rich layer (ALSI and ZRSI) and used to prepare experimental nanohybrid resin composites, which were characterized and compared to a control commercial resin composite (Filtek Z350 XT). MethodsSilica nanoparticles with sizes compatible to ALSI (Aerosil 150) and ZRSI (Aerosil OX 50) were tested as references. The volume of nanoparticles was equivalent across the composites, which also had consistent content of glass microparticles. CC conversion, viscosity, depth of cure, surface topography, hardness, opacity, radio-opacity, and edge chipping resistance (ReA) were tested after 24 h. Flexural strength (σf) and fracture toughness (KIC) were also tested after 15 K thermal cycles. Data were analyzed using one-way or two-way ANOVA and Tukey’s test (α = 0.05). ResultsALSI and ZRSI yielded resin composites with lower viscosity and more irregular nanoagglomerates compared to nanosilica-based composites. CC conversion and depth of cure were lower for ZRSI composite, which had higher opacity, radio-opacity, and hardness. ReA was higher for ALSI composite. Composites with ALSI and ZRSI showed stable σf after aging, whereas the control and Aerosil 150 resin composites showed significant degradation. The commercial and nanosilica-based composites showed up to 42% reduction in KIC after aging, whereas resin composites with ZRSI and ALSI showed a more stable KIC. SignificanceALSI and ZRSI generated nanohybrid resin composites with improved and/or more stable physical properties compared with nanosilica-based and commercial composites. This study suggests that changing the composition of nanofillers is a simple method to enhance the performance of nanohybrid composites.

Обнаружение частиц микропластика в растительных маслах

Наличие микро и нано частиц пластика в пищевых продуктах в настоящее время является актуальнейшей проблемой пищевой промышленности и одним из главных вопросов пищевой безопасности. При этом не существует ни чётких методик по определению таких частиц, ни способов очистки от них пищевых продуктов. В связи с тем, что вопрос о переработке пластика до сих пор не решён, а разлагающиеся пластиковые объекты находятся повсюду вокруг, крайне актуальным является изучение вопроса о наличии микроскопических частиц пластмасс (микропластика) в пищевых продуктах, об их размерах и количестве. В представленной работе впервые методом Динамического Лазерного Светорассеивания с помощью анализатора наночастиц «Zetatrac» было определено присутствие в некоторых растительных маслах микро и нано объектов, по своим характеристикам похожих на пластик. Определено распределение этих частиц по фракциям, их удельная поверхность и дзета потенциал. Было подсчитано содержание микро и нано частиц, идентифицированных, как пластик, в растительном масле. Оно колеблется от 2,5 до 9 миллиардов на один литр пищевого продукта. Высказано предположение, что возможной причиной наличия таких частиц в этом виде пищевых продуктов является то, что может происходить их экстракция из медленно разрушающейся пластиковой тары.Величина дзета потенциала, подсчитанная прибором на основании данных о движении частиц, находится в области от 20 до 30 мВ. Это значит, что микрочастицы в суспензии устойчивы и не склонны к коагуляции. Таким образом, самоочищение от них невозможно.

Blood-borne and brain-derived microparticles in morphine-induced anti-nociceptive tolerance

We hypothesized that elevations of microparticles (MPs) would occur with morphine administration to mice. Repetitive dosing to induce anti-nociceptive tolerance increases blood-borne MPs by 8-fold, and by 10-fold in deep cervical lymph nodes draining brain glymphatics. MPs express proteins specific to cells including neutrophils, microglia, astrocytes, neurons and oligodendrocytes. Interleukin (IL)-1β content of MPs increases 68-fold. IL-1β antagonist administration diminishes blood-borne and cervical lymph node MPs, and abrogates tolerance induction. Intravenous polyethylene glycol Telomer B, a surfactant that lyses MPs, and intraperitoneal methylnaltrexone also inhibit MPs elevations and tolerance. Critically, neutropenic mice do not develop anti-nociceptive tolerance, elevations of blood-borne or cervical node MPs. Immunohistochemical evidence for microglial activation by morphine does not correlated with the MPs response pattern. Neutrophil-derived MPs appear to be required for morphine-induced anti-nociceptive tolerance. Further, patients entering treatment for opioid use disorder exhibit similar MPs elevations as do tolerant mice.

Influence of different forms of iron on the morphobiological indicators of Pinus sylvestris

The wide distribution of iron in the environment of various forms of iron makes it relevant to study the characteristics of their influence on plant growth. In the present paper, the growth features of Pinus sylvestris – Scots pine were studied - during the cultivation of stratified seeds in a medium containing different forms of iron. It was established that the cultivation of pine seeds in a medium containing 0.1 M of iron in any form, inhibits the development of the root system. When cultivated in the environment containing iron nanoparticles at a concentration of 6.25 mmol / l, this led to a decrease in the root length to 3.71 ± 0.06 mm. On the contrary, the presence of iron nanoparticles in the medium for the cultivation of pine caused an increase in the length of the main and adventitious roots, as well as the number of adventitious roots. The content of iron microparticles in the medium for the cultivation of pine caused only a decrease in the length of the main root and adventitious roots. At the same time, at concentrations from 0.39 to 25 mmol / l, an increase in the number of adventitious roots occurred, which indicates compensatory reactions.

Prothrombotic State, Platelet Activation and Netosis in Systemic Lupus Erythematosus

Introduction: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown origin characterized by a hypercoagulable state and a high mortality rate. Mechanisms that cause the accelerated deterioration of cardiovascular health in SLE are unknown. Objectives: to characterize the prothrombotic state in SLE patients by global coagulation assays and the contribution of platelets, endothelial damage, microparticles and neutrophil extracellular traps (NETs) in their prothombotic profile. Material and methods: 72 patients and 90 healthy controls were recruited. Patients were classified according to clinical characteristics in: 32 with lupus (SLE group), 29 with SLE and antiphospholipid antibodies (aFL, SLE+aFL group) and 12 who met the criteria for SLE and antiphospholipid syndrome (APS, SLE+APS group). Experimental protocol was approved by La Paz University Hospital Ethics Committee. Venous blood collected in BD sodium citrate tubes (3.2%) was centrifuged at 150 g for 20 min at 23ºC to obtain platelet-rich plasma (PRP). PPP was obtained by centrifugation at 1500 g for 15 min at 23ºC. To obtain neutrophils, whole blood was centrifuged to 1600 rpm 25 min using a Ficoll gradient and red cells were lysed. Rotational thromboelastometry (ROTEM®) was performed in naTEM condition. Clotting time (CT, time from start of measurement until initiation of clotting [in seconds]); alpha angle (tangent to the curve at 2-mm amplitude [in degrees]), Ax (clot firmness at time x, [in mm]) and maximum clot firmness (MCF, [in mm]) were recorded. Procoagulant activity associated to microparticle's content of tissue factor was determined in PPP by Calibrated Automated Thrombogram (CAT) using MP-reagent (4 mM phospholipids, Diagnostica Stago, Spain). We evaluated the endogenous thrombin potential (ETP, the total amount of thrombin generated over time); the lag time (the time to the beginning of the explosive burst of thrombin generation); the peak height of the curve (the maximum thrombin concentration produced) and the time to the peak. Thrombin generation associated to NETs was also measured by CAT. Neutrophils from healthy controls or from LES patients were stimulated with 100 nM PMA in RPMI medium during 45 min at 37º and then cocultivated with PRP adjusted to 105 platelets/µL. NETs formation was verified by fluorescent microscopy performed with DAPI and an anti-myeloperoxidase antibody. Plasma levels of LDL-ox, E-Selectin and PAI-1 were determined by Elisa (R&amp;D Systems, MN, USA and Affymetrix eBioscience, Vienna, Austria, respectively). Platelet activation was analysed by flow cytometry (FCM, FACScan, BD Biosciences). Fibrinogen receptor activation was evaluated through PAC1-FITC binding and release of granule's content was assessed with monoclonal antibodies (mAbs) anti-CD63 and anti P-selectin in quiescent and 100 µM TRAP and 10 µM ADP stimulated platelets. Data were analysed with Graphpad prism and p ≤0.05 was stablished as statistical significance. Results: PAI-1 plasma level was increased in all patient's groups, whereas LDL-ox and E-selectin showed no differences with control cohort (Fig.1). ROTEM demonstrated a procoagulant profile in SLE and SLE+aPL but not in SLE+APS group (Fig. 2). PAI-1 levels correlated with several ROTEM parameters (Table 1). SLE patients and SLE+aFL showed a basal platelet activation. Moreover, SLE group exposed more P-selectin and CD63 than controls (Fig.3). Regarding thrombin generation associated to tissue-factor content of microparticles, no differences were observed between SLE patients and healthy controls. On the other hand, SLE patients had an increased peak of thrombin generation related to NETs formation (control group: 170.3± 58.0, SLE patients: 230.6±39.3, p=0.019). Conclusions: ROTEM® detected a hypercoagulable state in SLE and SLE+aPL patients. The hypercoagulable state might be linked to increased PAI-1 plasma levels and basal platelet activation in SLE and SLE+aPL groups. Moreover, neutrophils from SLE patients seemed to present a basal activation that induced a NETs-related procoagulant state in these patients. SLE+APS patients did not show a hypercoagulable state perhaps because of the presence of lupus anticoagulant and/or to therapeutic treatment of these patients. This work was supported by grants from the FIS-FONDOS FEDER (PI15/01457, NB). NVB holds a Miguel Servet tenure track grant from FIS-FONDOS FEDER (CP14/00024). Disclosures Fernandez-Bello: Novartis, Pfizer, ROCHE, Stago: Speakers Bureau. Robles:ABBVIE, SANDOZ FARMACEUTICA: Speakers Bureau. Álvarez Roman:Sobi: Consultancy, Speakers Bureau; CSL Behring: Consultancy, Speakers Bureau; Roche: Consultancy, Speakers Bureau; Pfizer: Consultancy, Speakers Bureau; Bayer: Consultancy, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Takeda: Research Funding; NovoNordisk: Consultancy, Speakers Bureau. Canales:Celgene: Honoraria; Gilead: Honoraria; Novartis: Honoraria; Janssen: Honoraria, Speakers Bureau; Sandoz: Honoraria; iQone: Honoraria; Takeda: Speakers Bureau; SOBI: Research Funding; Karyopharm: Honoraria; F. Hoffmann-La Roche Ltd: Honoraria, Speakers Bureau. Jimenez-Yuste:Bayer, CSL Behring, Grifols, Novo Nordisk, Octapharma, Pfizer, Roche, Sobi, Shire: Consultancy, Honoraria, Other: reimbursement for attending symposia/congresses , Research Funding, Speakers Bureau. Butta:Novartis: Consultancy; Roche, Pfizer: Speakers Bureau.