Goodfaber7431
Local resection or ablation remains an important approach to treat drug-resistant central neurological disease. Conventional surgical approaches are designed to resect the diseased tissues. The emergence of photothermal therapy (PTT) offers a minimally invasive alternative. However, their poor penetration and potential off-target effect limit their clinical application. Here, polydopamine nanoparticles (PDA-NPs) were prepared and characterized. Studies were performed to evaluate whether PDA-NPs combined with near-infrared (NIR) light can be used to ablate deep brain structures in vitro and in vivo. PDA-NPs were prepared with a mean diameter of ∼150 nm. The particles show excellent photothermal conversion efficiency. PDA-NPs did not show remarkable cytotoxicity against neuronal-like SH-SY5Y cell lines. However, it can cause significant cell death when combined with NIR irradiation. Transcranial NIR irradiation after PDA-NPs administration induced enhanced local hyperthermia as compared with NIR alone. Local temperature exceeded 60 °C after 6 min of irradiation plus PDA while it can only reach 48 °C with NIR alone. PTT with PDA (10 mg/mL, 3 μL) and NIR (1.5 W/cm2) can ablate deep brain structures precisely with an ablation volume of ∼6.5 mm3. Histological analysis confirmed necrosis and apoptosis in the targeted area. These results demonstrate the potential of NP-assisted PTT for the treatment against nontumorous central neurological diseases.Poly(propylene carbonate) (PPC) has aroused extensive attention in the biomaterial field because of its excellent biocompatibility and appropriate degradability, but surface hydrophobicity and bioinertness limit its applications for bone repair and tissue engineering. In this study, a bioactive PPC/laponite (LAP) nanocomposite (PL) was prepared by a melt-blending method, and a microporous surface on PPC and PL (PT and PLT) was created by sodium hydroxide (NaOH) treatment. The results demonstrated that the surface roughness, hydrophilicity, surface energy, and degradability as well as protein adsorption of PLT were obviously improved compared with PPC. Moreover, the degradability of PLT was remarkably enhanced with a slight increase of pH values in Tris-HCl solution. Furthermore, adhesion and proliferation as well as osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) to PLT were significantly promoted compared with PPC. The results suggested that incorporating LAP into PPC obviously improved the surface performance of PL (with nanotopography), and surface treatment with NaOH further enhanced surface properties of PLT (with micronanotopography and hydrophilic groups), which significantly promoted responses of rBMSCs. In short, PLT displayed excellent cytocompatibility, which would have great potential for bone regeneration.Cannulated screws have a structure for inserting a guide wire inside them to effectively correct complicated fractures. Magnesium, an absorbable metal used to manufacture cannulated screws, may decompose in the body after a certain period of implantation. The hydrogel formed by hyaluronic acid (HA) and polygalacturonic acid (PGA) has been used into Mg-based cannulated screws to prevent bone resorption owing to the rapid corrosion of Mg with unfavorable mechanical properties and a high ambient pH. In addition, Ca ions were added to the gel for cross-linking the carboxyl groups to modify the gelation rate and physical properties of the gel. The developed hydrogels were injected into the Mg-based cannulated screws, after which they released HA and Ca. The possibility of the application of this system as a cannulated screw was evaluated based on the corrosion resistance, gel degradation rate, HA release, toxicity toward osteocytes, and experiments involving the implantation of the screws into the femurs of rats. Ca ions first bound to PGA and delayed the gelation time and dissolution rate. However, they interfered with HA binding and increased the elution of HA at the beginning of gel degradation. Ca(NO3)2 concentrations higher than 0.01 M and low pH environments inhibited osteoblast differentiation and proliferation, owing to the elution of HA from the hydrogel. On the other hand, when the HA hydrogel with a proper amount of Ca was inserted into a magnesium screw, the degradation of Mg was delayed, and the presence of the gel contributed to new bone formation and osteocyte expansion.Silver nanocrystals have been successfully fabricated by the bioreduction route using the ethanolic extract of Azadirachta indica (neem) leaves as the reducing and capping agent without solvent interference. The silver nanocrystals were grown in a single-step method, without the influence of external energy or surfactants, and at room temperature. The nanoparticles were prepared from different ratios of silver ions to reducing agent molecules and were characterized by UV-vis spectroscopy and transmission electron microscopy (TEM). The nanoparticles were roughly spherical and polydispersed with diameters of less than 40 nm, as determined with high-resolution transmission electron microscopy (HRTEM). Fast Fourier transform (FFT) analysis and X-ray diffraction (XRD) analysis elucidated the crystalline nature of the nanoparticles. The presence of participating functional groups was determined with Fourier transform infrared (FTIR) spectroscopy. The synthesized silver nanoparticles were analyzed as a potential surf Pseudomonas nitroreducens, a biofilm-forming bacterium, and the fungus, Aspergillus unguis (NII 08123).Outer membrane protein A (OmpA) has been extensively studied in Gram-negative bacteria due to its relevance in the adhesion of pathogens to host cells and its surfactant capabilities. ICI118551 It consists of a hydrophobic β-barrel domain and a hydrophilic periplasmic domain, that confers OmpA an amphiphilic structure. This study aims to elucidate the capacity of Escherichia coli OmpA to translocate liposomal membranes and serve as a potential cell-penetrating vehicle. We immobilized OmpA on magnetite nanoparticles and investigated the possible functional changes exhibited by OmpA after immobilization. Liposomal intake was addressed using egg lecithin liposomes as a model, where magnetite-OmpA nanobioconjugates were able to translocate the liposomal membrane and caused a disruptive effect when subjected to a magnetic field. Nanobioconjugates showed both low cytotoxicity and hemolytic tendency. Additional interactions within the intracellular space led to altered viability results via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT).