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Our results suggest that PVA hydrogels combined with BNNSs outperform single-network PVA hydrogels in terms of thermal-healing capacity. As above Tg, the thermal energy gained during moisture loss leads to an increase in the thermal mobility of the polymer chains and in the free volume available for new hydrogen bonds at the fracture surface. This unique structure increases water content and confers better mechanical properties. Interestingly, this structure of the second network benefits the first PVA network during deformation by effectively dissipating energy and bearing force, and contrarily to single-network PVA hydrogels. Taken together, our results show that combining PVA and BNNSs to create a hybrid structure, exerts a synergistic effect and successfully improves the thermal-healing performance of wet hydrogels.Increasing evidences are demonstrating that structural and functional properties of non-neuronal brain cells, called astrocytes, such as those of cytoskeleton and of ion channels, are critical for brain physiology. Also, changes in astrocytes structure and function concur to and might determine the outcome of neuronal damage in acute neurological conditions or of chronic disease. Thus, the design and engineering of biomaterials that can drive the structural and functional properties of astrocytes is of growing interest for neuroregenerative medicine. Poly-ɛ-caprolactone (PCL), is FDA-approved polyester having excellent mechanical and chemical properties that can be tailored to obtain neural implants for regenerative purposes. However, the study on the use of PCL substrates for neuroregenerative purposes are mainly aimed at investigating the interaction of the material with neurons. Here, we report on the long-term viability, morphology, structural and functional properties of primary astrocytes grown on electrospun fibres of PCL (-GEL) and on blending of PCL and Gelatin protein (+GEL). We found that topography and morphological features of the substrate are the properties that mainly drives astrocytes adhesion and survival, over the long term, while they do not alter the cell function. Specifically, aligned PCL fibres induced in astrocytes a dramatic actin-cytoskeletal rearrangement as well as focal adhesion point number and distribution. Interestingly, structural changes observed in elongated astrocytes are not correlated with alterations in their electrophysiological properties. Our results indicated that PCL electrospun fibres are a permissive substrate that can be tuned to selectively alters astrocytes structural components while preserving astrocytes function. The results open the view for the use of PCL based electrospun fibres to target astrocytes for the treatment of brain dysfunction such as injuries or chronical disease.Nanotechnology has revolutionized many fields and produced nanostructures are promising materials for different industries. Nanoadsorbents as an emerging class of nanostructures can have potential applications for the separation and removal of both hazardous materials (such as heavy metals from water) and useful ingredients (such as vitamins and natural pigments from food wastes). The present study introduces a novel nanoadsorbent based on the ternary combination of zero valent iron/graphene oxide/active carbon (nZVI/GO-AC) with different formulations and using ultrasonication for improved physical properties. The nanocomposites were prepared by sodium borohydride reduction of graphene oxide, active carbon and ferrous sulfate under a nitrogen atmosphere and ultrasonication. Characterization of the developed nanocomposites was done by instrumental techniques, such as FTIR, VSM, FE-SEM, XRD, EDS, AFM and Raman analysis. The results indicated that the size of particles was 50 nm in the blank sample; however, when GO entered the composition, the particle size switched to less then 10 nm (either with or without ultrasonication). Also, the crystallinity of the ultrasound-assisted prepared nanocomposites enhanced by rapid nucleation in this method. Interestingly, the nanocomposites were superparamagnetic at ambient temperature and were separated by an external magnetic field. Altogether, at lower concentrations of GO in comparison to active carbon, the space between the GO sheets was higher and thus, there was more space for the accommodation of nZVI, which raises the rate of adsorbance. The immobilization process of nZVI on the composite platform improves the stability of the nZVI, whereas graphene coupling accelerates the transfer of electrons in nZVI and hinders the surface passivation of nZVI, resulting in the adsorption of target compounds.In response to changeful tumor environment, self-targeting antibody-mediated drug nanocarrier with functionalization have been broadly developed to realize specific antitumor efficacy. In this work, an antibody-conjugated drug delivery system with pH/temperature dual-responsive property was devised and fabricated based on mesoporous silica nanoparticle (MSN). Briefly, MSN was first modified with the pH/temperature dual-responsive macromolecular copolymer P(NIPAm-co-MAA) via a precipitation polymerization method, and then grafted with the anti-human epidermal growth factor receptor 2 (HER2) single chain antibody fragment (scFv) to specifically target HER2 positive breast cancer cells. Namodenoson ic50 With this structure, such targeting nanoparticles eventually exhibited high drug loading capacity and good biocompatibility. Meanwhile, the cumulative in vitro drug release profile displayed a low-level early leakage at neutral pH values/low temperature while remarkably enhanced release at an acidic pH value/high temperature, indicating an apparent pH/temperature-triggered drug release pattern. Moreover, tumor-targeting assay revealed that the anti-HER2 scFv-surface decoration greatly enhanced the cellular uptake of as-prepared nanoparticle through HER2-antibody-mediated endocytosis, as well as improved the uptake selectivity between normal and cancer cells. More importantly, both the in vitro and in vivo anticancer experiments indicated that such targeting dual-responsive nanoplatform could efficiently inhibit the growth of HER2 positive breast cancer with minimal side effects. Collectively, all these results promised such specific-targeted and dual-responsive nanoparticle a smart drug delivery system, and it provided a promising perspective in efficient and controllable cancer therapeutic application.The ternary HAp/curdlan/nanomagnetite hybrids with ceramic and polymer phase incorporation of magnetite nanoparticles (MNPs) were fabricated to study their heating ability under action of the alternating magnetic field (AMF), 808 nm near infrared laser radiation (NIR) and their synergic stimulation. The energy conversion was evaluated in terms of the specific absorption rate (SAR) as a function of the MNPs concentration in composites and to estimate their potential in temperature-controlled regenerative processes and hyperthermia. Measurements were carried out on dry and Ringer's solution soaked composite materials in order to mimic in situ conditions. It was found that the MNPs release during prolonged experiment is limited and has no significant effect on energy conversion emphasizing stability of the hybrids. Incorporation of the MNPs in polymer phase of the hybrid can additionally limit particle leaking as well as plays a role as insulating layer for the heat dissipation lowering the risk of sample overheating. In general, it was shown that maximum temperature of hybrid can be achieved in a relatively short time of exposure to stimulating factors whereas its control can be done through optimization of experiment conditions. MNPs incorporation into the curdlan (polymer phase) lead to strengthening of the mechanical properties of the whole network.Paraquat, one of non-selective herbicides, is widely used in agricultural production. However, it can cause death of people or animals quickly owing to its fatal toxicity. In the present work, for efficient separation and removal of the paraquat, a concept "employ collaboration effect to enhance the Host-Guest interactions" was rationally introduced into the design of paraquat adsorbent material. According to this concept, a novel linear tri-pillar[5]arene-based acceptor molecule was synthesized. Interestingly, the acceptor shows outstanding adsorption properties for paraquat through the collaboration effect of the adjacent pillar[5]arene moieties in the linear tri-pillar[5]arene acceptor. Compared with other adsorbents such as activated carbon and single-pillar[5]arene-based adsorbent materials, the linear tri-pillar[5]arene acceptor shows higher adsorption rate for paraquat. Additionally, the linear tri-pillar[5]arene acceptor was applied to adsorb the commercial pesticide paraquat sample in water with adsorption rate of 98%. Therefore, the linear tri-pillar[5]arene acceptor could serve as a paraquat adsorbent material and convey greatly potential application in the field of removal of paraquat. The concept "employ collaboration effect to enhance the Host-Guest interactions" is a useful way for the development of adsorption materials.Nanogel based on polysaccharides has attracted the tremendous interest due to its unique performance as drug carrier for in vivo release. In this work, the multi-responsive nanogels were developed based on the tailor-modified sugarcane bagasse cellulose (SBC). In the presence of crosslinking agent cystamine bisacrylamide (CBA), the in-situ free radical copolymerization of methacrylated monocarboxylic sugarcane bagasse cellulose (MAMC-SBC) and N-isopropylacrylamide (NIPAM) in aqueous phase was conducted, thus leading to redox, pH and thermal-responsive nanogels. The results obtained from FT-IR, SEM and particle sizer showed that the nanogels were highly stable with the desired particle size ranging from 90 to 180 nm and contained targeted polymeric segments and linkage for multi-responsivity. Doxorubicin hydrochloride (DOX) as a model drug was effectively loaded into the nanogels, partly driven by strong electrostatic association; and the loading efficiency reached up to 82.7%. Moreover, the drug release could be readily manipulated by the addition of reducing agent, pH and temperature, which is attributed to the multi-responsive behavior of nanogels as carrier and synergetic effects. The performance of nanogels was also governed by the ratio of reactive MAMC-SBC and NIPAM during polymerization; and the ratio at 11(wt) led to the optimal structure of nanogels.The present study aimed to develop nanocapsules (NCs) loaded with curcumin (CCM) using different coatings, comparing the effect of these coatings on physicochemical properties of NCs. NCs were prepared by interfacial deposition of performed polymer, using different polymers as coatings (P80, PEG, Chitosan and Eudragit RS100®) and then, characterized in detail by different techniques (AFM, FTIR, DSC, XRD, among others). In vitro studies were performed, evaluating the release profile, cytotoxicity and antimalarial activity of CCM-loaded NCs. Overall, all CCM-loaded NCs samples exhibited typical characteristics as nanometric size, coating-dependent zeta potential, acidic pH value, span values below 2, homogeneous morphology and CCM-distribution in pseudophases of type VI (for all of coatings). Experimental results showed that CCM remains stable in lipid-core of NCs, maintaining its physicochemical and biological properties after nanoencapsulation process. In vitro release assays showed that nanoencapsulation was an efficient strategy to controlled release of CCM and P80-coated NCs presented slowest CCM-release considering all nanoformulations tested.

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