High Levels Of Adhesion Research Articles

Organic-Inorganic Hybrid Planarization and Water Vapor Barrier Coatings on Cellulose Nanofibrils Substrates.

Cellulose nanofibrils (CNF) can be produced in the form of thin, transparent and flexible films. However, the permeability of such materials to oxygen and water vapor is very sensitive to moisture, which limits their potential for a variety of packaging and encapsulation applications. Diffusion barrier coatings were thus developed to reduce the access of water molecules to enzymatically pre-treated and carboxymethylated CNF substrates. The coatings were based on UV curable organic-inorganic hybrids with epoxy, tetraethylorthosilicate (TEOS) and 3-glycidoxypropyltrimethylenesilane (GPTS) precursors and additional vapor formed SiNx layers. A total of 14 monolayer and multilayer coatings with various thickness and hybrid composition were produced and analyzed. The water vapor transmission rate (WVTR) of the bilayer epoxy/CNF film was two times lower compared to that of uncoated CNF film. This was partly due to the water vapor permeability of the epoxy, a factor of two times lower than CNF. The epoxy coating improved the transparency of CNF, however it did not properly wet to the CNF surfaces and the interfacial adhesion was low. In contrast hybrid epoxy-silica coatings led to high adhesion levels owing to the formation of covalent interactions through condensation reactions with the OH-terminated CNF surface. The barrier and optical performance of hybrid coated CNF substrates was similar to that of CNF coated with pure epoxy. In addition, the hybrid coatings provided an excellent planarization effect, with roughness close to 1 nm, one to two orders of magnitude lower than that of the CNF substrates. The WVTR and oxygen transmission rate values of the hybrid coated CNF laminates were in the range 5–10 g/m2/day (at 38°C and 50% RH) and 3–6 cm3/m2/day/bar (at 23°C and 70% RH), respectively, which matches food and pharmaceutical packaging requirements. The permeability to water vapor of the hybrid coatings was moreover found to decrease with increasing the TEOS/GPTS ratio up to 30 wt% and then increase at higher ratio, and to be much lower for thinner coatings due to further UV-induced silanol condensation and faster evaporation of byproducts. The addition of a single 150 nm thick SiNx layer on the hybrid coated CNF improved its water vapor barrier performance by more than 680 times, with WVTR below the 0.02 g/m2/day detection limit.

The hierarchical micro-/nanotextured topographies promote the proliferation and angiogenesis-related genes expression in human umbilical vein endothelial cells by initiation of Hedgehog-Gli1 signaling

The hierarchical microtextured/nanotextured topographies have been recognized to have better tissue integration properties, but the underlying mechanisms are only partially understood. Hedgehog signaling plays a pivotal role in developmental and homeostatic angiogenesis. We suppose that the Hedgehog-Gli1 signaling may play a significant role in the response of endothelial cells to microtextured/nanotextured topographies (MNTs). To confirm this hypothesis, we produced the MNTs decorated with TiO2 nanotubes of two different diameters (25 and 70 nm), and the proliferation, apoptosis, angiogenesis-related genes expression and Hedgehog signaling activity of human umbilical vein endothelial cells (HUVECs) grown onto these MNTs were measured. Our results showed that the MNTs induced significantly high expression of Sonic Hedgehog (SHH), Smoothened (SMO) and GLI1 in the HUVECs as well as high activation of Hedgehog-Gli1 signaling, compared to the smooth surface. The HUVECs grown on the MNTs showed significantly high levels of adhesion, proliferation and expression of angiogenesis-related genes, including angiopoietin-1 (ANG-1), vascular endothelial growth factor (VEGFA), vascular endothelial growth factor receptor 2 (VEGFR2) and endothelial nitric oxide synthase (ENOS); these enhancements were attenuated by siRNA-mediated depletion of SMO, which indicated a significant role of Hedgehog-Gli1 signaling in mediating the enhanced effect of the MNTs on the angiogenic potential of HUVECs. This study may contribute to the modification of biomaterial surfaces for better tissue integration and clinical performance.

Tribo-Corrosion and Corrosion Behaviour of Titanium Alloys with and Without DLC Films Immersed in Synthetic Urine

Nowadays, potable water is becoming scarcer, and chemicals components present in wastewater increase corrosion of devices and decrease its lifespan, especially from bearings used in water recovery system. The bearings are subjected to severe corrosion due to harsh environmental conditions from urine composition. 60NiTi alloy which was developed to attend International space station requirements as a resistant material to recycle wastewater to potable water, together DLC film as a solid lubricant, could be new protective material to avoid tribo-corrosion and corrosion from devices under hostile environment. In this work, we compared the tribocorrosion resistance of 60NiTi, also named as NiTi60T and thermally treated, and Ti–6Al–4V alloys with and without diamond-like carbon (DLC) film. The NiTi60T is a promising candidate to be used for the centrifuge bearings to expand their lifespan when in contact with synthetic urine. The DLC film presented high levels of wear resistance, metallic adhesion, and corrosion protection for both tested alloys.

Development and characterization of poly(ethylene terephthalate) based injection molded self-reinforced composites. Direct reinforcement by overmolding the composite inserts

This work presents the concept of using the self-reinforced inserts, suitable for overmolding during the standard injection molding procedure. The reinforcing inserts made from self-reinforced poly(ethylene terephtahalte) sheets (srPET) were overmolded by the matrix polymer. Two types of poly(ethylene terephthalate) were used as the matrix material, PET (pure bottle grade resin) and G-PET (amorphous PET based copolymer). Samples prepared under different conditions of the injection molding process were tested in terms of mechanical properties, DMA and DSC analysis. The results of mechanical tests confirmed the different fracture behavior, more favorable for G-PET samples, where the increase of tensile strength and E modulus reached 60% and 32% respectively. The most significant increase was observed for impact resistance values, for both types of polyesters the impact strength reach around 50 kJ/m2, from the initial value below 5 kJ/m2. The SEM microscopy was used to investigate the morphology of matrix-reinforcement interface. The observations of the bonding interface indicate the lack of delamination process and high level of adhesion between the matrix materials and reinforcing srPET insert. The presented results confirm that the proposed concept of using the overmolding technology for preparation of self-reinforced composites has the potential for industrial implementation.

Structures and Adhesion Properties at Polyethylene/Silica and Polyethylene/Nylon Interfaces.

The molecular structures of buried interfaces of maleic anhydride grafted and ungrafted polyethylene films with silica and nylon surfaces were studied in situ using sum-frequency generation (SFG) vibrational spectroscopy. Grafting maleic anhydride to polyethylene altered the molecular structures at buried interfaces, including changing the orientation of polymer methylene groups and resulting in the presence of C═O groups at silica interfaces. These molecular level changes are correlated with enhanced adhesion properties, with ordered C═O groups and in-plane orientation of the methylene groups associated with higher levels of adhesion. While improved adhesion was observed for grafted polyethylene at the nylon interface, no C═O groups were detected at the interface using SFG, for films thermally treated at 185 °C. In this case, either no C═O groups are present at the interface or they are disordered; the latter explanation is more likely, considering the observed improvement in adhesion.

Пробіотичні властивості бактерій роду Lactobacillus, виділених зі шлунково-кишкового тракту кроликів

The probiotic properties (antagonistic and adhesion) of lactic acid bacteria isolated from the gastrointestinal tract of rabbits were studied. It was established that the studied antagonistic activity to pathogenic and conditionally pathogenic microorga­nisms was observed in the following strains: Lactobacillus lactis 4/1, Lactobacillus casei 5/4, Lactobacillus helveticus 13/2, Lactobacillus plantarum 17/2, Lactobacillus plantarum 17/3, Lactobacillus acidophilus 49/1. The level of adhesion of lactic acid bacteria isolate, isolated from the gastrointestinal tract of rabbits, to erythrocytes of rabbit, mouse, pig, cattle, human blood was studied. The highest level of adhesion (83 %) was observed in erythrocytes of rabbits, low (53 %) – in erythrocytes of cattle. The possibi­lity of using the L. helveticus 13/2 strain for the prevention and treatment of salmonella infections has been shown. Introduction to research animals of lactic acid bacteria before infection with pathogens of salmonellosis allowed to save 90–100 % of experimental animals. With the use of lactic acid bacteria after infection of salmonellosis to animals, the safety of the herd was 67–73 %.

Mini Review: Nanosheet Technology towards Biomedical Application.

The fabrication technique of ultrathin film (commonly known as nanosheets) has been significantly developed over the years. Due to the mechanical properties of nanosheets, such as high levels of adhesion and flexibility, this made nanosheets the ideal candidate in biomedical applications. In this review, innovative biomedical applications of nanosheets are discussed, which include, drug delivery, wound treatment, and functional nanosheets towards flexible biodevices, etc. Finally, the future outlook of nanosheet technology towards a biomedical application is discussed.

Rheology and bioactivity of high molecular weight dextrans synthesised by lactic acid bacteria

Dextrans synthesised by three Leuconostoc mesenteroides strains, isolated from mammalian milks, were studied and compared with dextrans produced by Lc. mesenteroides and Lactobacillus sakei strains isolated from meat products. Size exclusion chromatography coupled with multiangle laser light scattering detection analysis demonstrated that the dextrans have molecular masses between 1.74×108Da and 4.41×108Da. Rheological analysis of aqueous solutions of the polymer revealed that all had a pseudoplastic behaviour under shear conditions and a random, and flexible, coil structure. The dextrans showed at shear zero a difference in viscosity, which increased as the concentration increased. Also, the purified dextrans were able to immunomodulate in vitro human macrophages, partially counteracting the inflammatory effect of Escherichia coli O111:B4 lipopolysaccharide. During prolonged incubation on a solid medium containing sucrose, dextran-producing bacteria showed two distinct phenotypes not related to the genus or species to which they belonged. Colonies of Lc. mesenteroides CM9 from milk and Lb. sakei MN1 from meat formed stable and compact mucoid colonies, whereas the colonies of the other three Leuconostoc strains became diffuse after 72h. This differential behaviour was also observed in the ability of the corresponding strains to bind to Caco-2 cells. Strains forming compact mucoid colonies showed a high level of adhesion when grown in the presence of glucose, which decreased in the presence of sucrose (the condition required for dextran synthesis). However no influence of the carbon source was detected for the adhesion ability of the other Lc. mesenteroides strains, which showed variable levels of binding to the enterocytes.

Identification of different macrophage subpopulations with distinct activities in a mouse model of oxygen-induced retinopathy.

The aim of the present study was to characterize the phenotypic shift, quantity and role changes in different subgroups of retinal macrophages in a mouse model of oxygen-induced retinopathy (OIR). The mRNA expression levels of macrophage M1 and M2 subgroup marker genes and polarization-associated genes were analyzed by RT-qPCR. The number of M1 and M2 macrophages in our mouse model of OIR was analyzed by flow cytometry at different time points during the progression of OIR. Immunofluorescence whole mount staining of the retinas of mice with OIR was performed at different time points to examine the influx of macrophages, as well as the morphological characteristics and roles of M1 and M2 macrophages. An increased number of macrophages was recruited during the progression of angiogenesis in the retinas of mice with OIR due to the pro-inflammatory microenvironment containing high levels of cell adhesion and leukocyte transendothelial migration molecules. RT-qPCR and flow cytometric analysis at different time points revealed a decline in the number of M1 cells from a significantly high level at post-natal day (P)13 to a relatively normal level at P21, as well as an increase in the number of M2 cells from P13 to P21 in the mice with OIR, implicating a shift of macrophage polarization towards the M2 subtype. Immunofluorescence staining suggested that the M1 cells interacted with endothelial tip cells at the vascular front, while M2 cells embraced the emerging vessels and bridged the neighboring vessel sprouts. Thus, our data indicate that macrophages play an active role in OIR by contributing to the different steps of neovascularization. Our findings indicate that tissue macrophages may be considered as a potential target for the anti-angiogenic therapy of ocular neovascularization disease.

Formulation and characterization of chitosan-based biocomposites with potential use for bone adhesion

ABSTRACTThe effects of the addition of calcium carbonate (CC) and hydroxyapatite (HA) in chitosan-based biocomposites were studied keeping in mind their potential use as bone adhesives. The formation of coordination bonds between calcium ions and chitosan amino groups was evident, producing ionic cross-links between chitosan macromolecules, which changed chitosan gelation mechanisms, gel strengths, and adhesiveness into bone surfaces; CC concentration is a key factor in these phenomena. A formulation with 2% chitosan and 4% of both CC and HA showed the most promising performance having high levels of adhesion to bone surfaces (0.27 MPa) and a cohesive mode of failure.

A sterilizable, biocompatible, tropoelastin surface coating immobilized by energetic ion activation.

Biomimetic materials which integrate with surrounding tissues and regulate new tissue formation are attractive for tissue engineering and regenerative medicine. Plasma immersion ion-implanted (PIII) polyethersulfone (PES) provides an excellent platform for the irreversible immobilization of bioactive proteins and peptides. PIII treatment significantly improves PES wettability and results in the formation of acidic groups on the PES surface, with the highest concentration observed at 40-80 s of PIII treatment. The elastomeric protein tropoelastin can be stably adhered to PIII-treated PES in a cell-interactive conformation by tailoring the pH and salt levels of the protein-surface association conditions. Tropoelastin-coated PIII-treated PES surfaces are resistant to molecular fouling, and actively promote high levels of fibroblast adhesion and proliferation while maintaining cell morphology. Tropoelastin, unlike other extracellular matrix proteins such as fibronectin, uniquely retains full bioactivity even after medical-grade ethylene oxide sterilization. This dual approach of PIII treatment and tropoelastin cloaking allows for the stable, robust functionalization of clinically used polymer materials for directed cellular interactions.

Promotion of Adhesion of Green Flame Retardant Coatings onto Polyolefins by Depositing Ultra-Thin Plasma Polymer Films: A Critical Review

Various methods have been used for introducing fire retardant additives into polymers. Deposition of thick fire retardant coatings directly onto polymer substrates is an alternative technique. An important advantage of the coating technique is the preservation of the physical and chemical integrity of the polymer material. Moreover, the fire retardancy of the polymer materials can be achieved following their production. Suitable coating materials are inorganics, intumescent, char-forming, oxygen-diluting, and cooling or radical quenching layers. The most important problem is to achieve sufficient coating thickness to withstand the direct attack of flame and to protect the polymer bulk from pyrolysis, otherwise blistering of coating, caused by emitted pyrolysis gases, is often observed. To avoid blistering of coating, the adhesion between polyolefin substrate and fire retardant coating has to be extraordinarily high. In order to achieve such a high level of adhesion, the polymer surface has to be modified with adhesion-promoting functional groups. The deposition of thin plasma polymers as adhesion-promoting layers with NH2, OH or COOH groups has been the most suited method. These functional groups are able to form covalent bonds and other interactions between the fire-resistant coating and the plasma-modified polyolefin substrate. Additionally, the plasma polymer counteracts the strong mechanical stresses in the laminate on exposure to high temperatures by its flexibility. The thick fire retardant coatings were chosen based on green ecological aspects to avoid flame-initiated emission of toxic or corrosive gases and remains of toxic char.

Early Enhancement of IgM Expression and Signaling Capacity during Ibrutinib Therapy in CLL Patients

In chronic lymphocytic leukemia (CLL), B-cell receptor (BCR) signaling is key to survival and proliferation, and can be effectively targeted by the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib. BCR surface IgM (sIgM) levels and signaling capacity are low but variable in CLL. The variability has clinical consequences and relatively high sIgM in circulating cells is associated with aggressive disease, a higher proliferative component and higher levels of adhesion and migration receptors (D'Avola, Drennan et al, Blood 2016).The aim of this study was to investigate the expression and function of sIgM and other surface markers on the circulating tumor cells of CLL patients following one week of ibrutinib therapy. Expression of markers associated with the BCR complex (IgM, IgD, CD19), and with adhesion or migration (CD38, CD49d, CXCR4) was assessed by flow cytometry in 13 CLL patients prior to and following one week of therapy. Signaling capacity was measured by immunoblotting following sIgM or CXCR4 stimulation. N-glycosylation status of the µ-heavy chains was measured by immunoblotting after biotinylation of cell surface proteins to determine IgM maturation (Krysov et al, Blood 2010).Following one week of treatment basal activity of BTK was significantly reduced compared with pre-treatment (P=0.002), and anti-IgM induced BTK auto-phosphorylation was completely suppressed, confirming full inhibition of BTK in vivo. Expression of sIgM, but not of sIgD, increased dramatically (P=0.005), with little change in the other receptors. The increase was similar in the tissue-egressed CXCR4dimCD5hi cells and in the CXCR4brightCD5low long-resting cells of the circulation. Increased sIgM expression associated with the fully N-glycosylated form of sIgM, characteristic of the absence of antigen engagement. Also, it correlated with increased capacity to phosphorylate SYK following anti-IgM stimulation (r=0.91, P<0.0001). Conversely, CXCL12-induced CXCR4 signaling, measured by ERK phosphorylation, was fully suppressed.Whilst ibrutinib induces a rapid and persistent redistribution of CLL cells into the blood, early suspension is typically associated with reduction of the lymphocytosis, nodal progression and short survival. These data reveal a dangerous early phenomenon during ibrutinib in which IgM expression has increased in the circulating cells, resulting in enhanced IgM-mediated signaling capacity through SYK. CXCR4 inhibition may prevent migration into tissue during ibrutinib and avoid (super)antigen encounter, but cells could be at risk of increased IgM mediated proliferation and disease progression if ibrutinib is withdrawn at this stage. DisclosuresPackham:Aquinox Pharmaceuticals: Research Funding; Karus Therapeutics: Other: Share Holder & Founder. Steele:Portola Pharmaceuticals: Honoraria.

Fabrication of Si negative electrodes for Li-ion batteries (LIBs) using cross-linked polymer binders.

Currently, Si as an active material for LIBs has been attracting much attention due to its high theoretical specific capacity (3572 mAh g−1). However, a disadvantage when using a Si negative electrode for LIBs is the abrupt drop of its capabilities during the cycling process. Therefore, there have been a few studies of polymers such as poly(vinylidene fluoride) (PVdF), carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR) and polyacrylic acid (PAA) given that the robust structure of a polymeric binder to LIBs anodes is a promising means by which to enhance the performance of high-capacity anodes. These studies essentially focused mainly on modifying of the linear-polymer component or on copolymers dissolved in solvents. Cross-linking polymers as a binder may be preferred due to their good scratch resistance, excellent chemical resistance and high levels of adhesion and resilience. However, because these types of polymers (with a rigid structure and cross-linking points) are also insoluble in general organic solvents, applying these types in this capacity is virtually impossible.

Inhibition of Migration and Invasion by Tet-1 Overexpression in Human Lung Carcinoma H460 Cells.

In the present study, we found that lung cancer cell line (H460 cells) expressing Tet1 showed higher levels of adhesion, and Tet1 inhibited H460 cell proliferation. In addition, these cells showed a significantly reduced ability of collagen degradation and Smad2/3 phosphorylation compared to controls. Furthermore, vimentin was found to be highly expressed in larger metastatic cancer area. Tet1 overexpression was reduced in the epithelial marker E-cadherin. Moreover, Tet1 repressed cancer cell metastasis in nude mice. Collectively, these findings suggest that Tet1 expression plays a critical role in metastasis of lung cancer cells by suppression of invasion and epithelial–mesenchymal transition (EMT).

Biomimetic interconnected porous keratin–fibrin–gelatin 3D sponge for tissue engineering application

The medicated wound dressing material with highly interconnected pores, mimicking the function of the extracellular matrix was fabricated for the promotion of cell growth. In this study, keratin (K), fibrin (F) and gelatin (G) composite scaffold (KFG-SPG) was fabricated by freeze drying technique and the mupirocin (D) drug was successfully incorporated with KFG-SPG (KFG-SPG-D) intended for tissue engineering applications. The fabrication of scaffold was performed without the use of any strong chemical solvents, and the solid sponge scaffold was obtained with well interconnected pores. The porous morphology of the scaffold was confirmed by SEM analysis and exhibited competent mechanical properties. KFG-SPG and KFG-SPG-D possess high level of biocompatibility, cell proliferation and cell adhesion of NIH 3T3 fibroblast and human keratinocytes (HaCaT) cell lines thereby indicating the scaffolds potential as a suitable medicated dressing for wound healing.

Distinct Bone Marrow Blood Vessels Differentially Regulate Normal and Malignant Hematopoietic Stem and Progenitor Cells

Bone marrow (BM) endothelial cells (BMECs) form a network of blood vessels (BVs) that regulate both leukocyte trafficking and hematopoietic stem and progenitor cell (HSPC) maintenance. However, it is not clear how BMECs balance between these dual regulatory roles and if these events occur at the same vascular site. We define the BM architecture of functionally distinct BVs, their spatial localization and association with specific stromal precursors, which cooperatively regulate HSPC fate. BM stem and progenitor cell maintenance in a metabolically non-active state and leukocyte trafficking occur at separate sites and are differentially regulated by specific BVs with distinct permeability properties. BM arteries were found to be mostly encircled by aSMA+ pericytes whereas the ensuing small-diameter endosteal and trabecular arterioles were predominantly surrounded by stem cell-niche supporting stromal precursor cells. Live imaging and flow analysis revealed that endosteal arteriole BVs exhibited high flow rate, low permeability to external plasma from the peripheral blood, and high levels of adhesion- and tight-junction molecules. Primitive HSPCs located in peri-arteriole regions were found in a non-activated, low reactive oxygen species (ROS) state. Exposure of BM HSPCs to peripheral blood plasma, enhanced their metabolic activity, exhibited by enhanced intracellular ROS levels, and glucose uptake. The same was also evident for circulating HSPCs in the blood. Plasma-exposed HSPCs displayed enhanced motility alongside with reduced long-term repopulation potential. Live imaging showed that all immature and mature leukocyte bi-directional trafficking occurred exclusively at the more permeable sinusoids, located downstream to the endosteal arterioles. Of note, BM sinusoids contained a higher prevalence of ROShigh cells in their microenvironment, including HSPCs. Rapid AMD3100-induced HSPC mobilization preferentially affected sinusoidal but not arterial BVs permeability and CXCL12 chemokine release. Endothelial specific in vivo interference with CXCL12-CXCR4 interactions, via conditional CXCR4 genetic deletion, hampered BM barrier integrity resulting in enhanced HSPC egress. In line with these results we found that during conditions favoring BM stem and progenitor cells expansion, endothelial integrity was enhanced along with reduced HSPC bi-directional trafficking. Conversely, conditional endothelial specific induced genetic or pharmacologic disruption of barrier integrity augmented ROS levels in HSPCs, enhancing their bi-directional trafficking and differentiation while reducing their BM pool size and maintenance in a metabolically non-active state. Of note, humanized mice engrafted with pre-B ALL cells exhibited reduced BM barrier permeability most probably due to BM endothelium modification via FGF-2 secretion by the leukemic clone. Interestingly, human pre-B ALL cells displayed hypersensitivity to plasmatic exposure. We hypothesize that malignant cells modify BM endothelium to provide themselves with a supportive and protective microenvironment composed of undifferentiated BM stromal progenitors and tightly sealed endothelial barrier. In conclusion, our study identifies anatomically distinct BM BVs with different barrier functions serving as systemic leukocyte trafficking or HSPC BM maintenance sites with clinical therapeutic relevance. DisclosuresRafii:Angiocrine Bioscience: Consultancy, Equity Ownership.

Modified platelet deposition on matrix metalloproteinase 13 digested collagen I

SummaryBackgroundAtherothrombosis underlies acute coronary syndromes, including unstable angina and acute myocardial infarction. Within the unstable plaque, monocytes express collagenolytic matrix metalloproteinases (MMPs), including MMP‐13, which degrades fibrous collagen. Following rupture, vessel wall components including degraded collagen are exposed to circulating platelets. Platelet receptors then mediate the recruitment and activation of platelets to form a thrombus, blocking blood flow and resulting in myocardial infarction and sudden death.ObjectivesHere we aim to provide information on the effects of collagen degradation on platelet adhesion and thrombus formation.MethodsUsing increasing concentrations of MMP‐13, we induced progressive degradation of fibrous and monomeric collagen I, visualized by electrophoresis, and then investigated the capacity of the resulting fragments to support static platelet adhesion and thrombus formation in whole flowing blood.ResultsBoth integrin and glycoprotein VI‐dependent interactions with fibrous collagen underpin high levels of platelet adhesion under both conditions, with little obvious effect of MMP‐13 treatment. Static platelet adhesion to monomeric collagen was strongly α2β1‐dependent regardless of degradation status. Under flow conditions, partially degraded monomeric collagen supported increased thrombus deposition at 10 μg mL −1 MMP‐13, falling close to background when collagen degradation was complete (100 μg mL −1 MMP‐13).ConclusionsNew binding activities come into play after partial digestion of collagen monomers, and net platelet‐reactivity through all axes is abolished as degradation becomes more complete.

Effect of aerobic training and aerobic and resistance training on the inflammatory status of hypertensive older adults.

There is a relationship between high levels of inflammatory markers and low adhesion to the practice of physical activity in the older population. The objective of the present study was to compare the effect of two types of exercise programs, i.e., aerobic training and aerobic plus resistance training on the plasma levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) of elderly hypertensive subjects. Hypertensive older volunteers in use of antihypertensive drugs were randomized to three groups: aerobic group (AG), resistance and aerobic group (RAG) and control group (CG). Training lasted 10weeks, with sessions held three times a week. Blood samples were collected before training and 24h after completion of the 30 sessions for the determination of serum IL-6 and TNF-α levels. Body mass index was obtained before and after 10weeks. After intervention, BMI values were lower in AG and RAG compared to CG (p<0.001), IL-6 was reduced in AG compared to CG (p=0.04), and TNF-α levels were lower only in RAG compared to CG (p=0.01). Concluding, both types of training were effective in reducing BMI values in hypertensive older subjects. Aerobic exercise produced the reduction of plasma IL-6 levels. However, the combination of aerobic and resistance exercise, which would be more indicated for the prevention of loss of functionality with aging, showed lower TNF-α mediator after training than control group and a greater fall of TNF-α levels associated to higher BMI reduction.

Genotypic and phenotypic features of Arcobacter butzleri pathogenicity

Even though Arcobacter butzleri has been implicated in some human disease as diarrhoea and bacteraemia, much of its pathogenesis and virulence factors remain unclear.In this work we have compared pathogenic and genotypic properties of six A. butzleri isolates from human and non-human sources. The tested isolates showed to be susceptible to tetracyclines and aminoglycosides, however non-human isolates were all resistant to quinolones. The ability to form biofilms was variable among the tested strains, and all of them showed a weak haemolytic activity. The presence of nine putative virulence genes was determined, with cadF, ciaB, cj1349, mviN, pldA, tlyA being detected in all strains, while irgA (3/6), hecA (5/6), hecB (4/6) were detected only in some strains. High levels of adhesion were observed for A. butzleri on Caco-2 cells, with pre-existing inflammation showing no significant effect on the adherence ability; yet variable levels of invasion were observed. A. butzleri isolates were able to survive intracellularly in Caco-2 cells and to induce a significant up-regulation of interleukin-8 secretion and structural cell rearrangements. These data brings new insights on A. butzleri virulence and highlights its pathogenic potential.