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In conclusion, the cell-free hydrogel, along with PN-KGN and TGF-β3, provides a promising strategy for cartilage repair by attracting endogenous MSCs and inducing chondrogenesis of recruited cells in a single-step procedure. Taking into account the potential of barium titanate to deliver electrical stimulation to the physiological microenvironment and offer beneficial conditions for the cellular metabolism, this mineral phase was selected for the development of new composites. In this context, calcium phosphates and barium titanate were deposited on bacterial cellulose membranes under ultrasonic irradiation, the resulting system being subjected to a thermal treatment in optimized conditions in order to remove the polymeric template and achieve 3D porous architectures. The complex characterization performed on the intermediate and final samples demonstrated the suitability of such materials for hard tissue engineering applications. In this study, three-dimensional macroporous cryogels were developed from platelet lysate (PL) and different concentrations of oxidized dextran (OD; 0.5, 1, 2, 4%). Subsequently, PL/OD scaffolds were characterized for potential use in tissue engineering applications. The pore size and morphology of the resulting cryogels were visualized using scanning electron microscopy (SEM). The pore size distributions were determined using mercury intrusion porosimetry (MIP). In vitro hydrolytic degradation, water uptake, mechanical properties and hemocompatibility were investigated. Extraction test was carried out to evaluate potential in vitro toxic effects of the PL/OD. The in vitro adhesion, proliferation, chondrogenic differentiation, and extracellular matrix production of human adipose stem cells (hASCs) on PL/OD cryogels were evaluated. In vivo biodegradation of the cryogels was investigated at the subcutaneous dorsal site of rats. SEM and MIP results indicated that PL/OD had a macroporous pore structure with pore sizes ranging between 10 and 200 μm. The cryogels completely degraded within 90-240 days post-implantation, depending on OD concentration. Histochemical analysis revealed high levels of cell and tissue infiltration into the pores of PL/OD. In vitro cytotoxicity findings indicated that the extracts of PL/OD0.5, PL/OD1 and PL/OD2 showed no cytotoxic effect, whereas that of PL/OD4 exhibited a moderate cytotoxic effect on cell cultures. hASCs seeded on PL/OD2 retained their viability and showed extensive spreading and filopodia formation after 7 days. PL/OD2 also supported the chondrogenesis of hASCs in the presence of chondro-inductive factors. Given all the results, PL/OD could have potential as a scaffold for tissue engineering applications. Peri-implantitis is the most important issue threatening the long-term survival rate of dental implants. Various efforts have been made to reduce implant surface plaque formation, which is one of the essential causes of peri-implantitis. In our study, we applied the natural antibacterial agent totarol as a coating on experimental silicon wafer and titanium implant surfaces. To analyze the interaction between the totarol coating and the oral primary colonizer S. gordonii and isolates of mixed oral bacteria, samples were incubated in a model system simulating the oral environment and analyzed by Live/Dead staining, crystal violet staining and scanning electron microscopy (SEM). After 4 d, 8 d, 12 d, 16 d, and 24 d salivary incubation, the stability and antibacterial efficiency of totarol coating was evaluated through SEM. The results indicated that totarol coatings on both silicon wafer and Ti surfaces caused efficient contact killing and an inhibition effect towards S. gordonii and mixed oral bacterial film growth after 4 h, 8 h, 24 h, and 48 h incubation. After longtime salivary incubation of 12 d, the bactericidal effect started to weaken, but the anti-adhesion and inhibition effect to biofilm development still exist after 24 d of salivary incubation. The application of a totarol coating on implant or abutment surfaces is a promising potential prophylactic approach against peri-implantitis. In this work, tantalum thin films were prepared on titanium substrates by an ion beam sputtering method. Tantalum thin films were irradiated by gamma-ray with different total dose levels. The effect of irradiation on the phase composition, microstructure, surface morphology, and chemical resistance were analyzed. Besides, in vitro cytocompatibility of tantalum films treated with different radiation doses were evaluated via 3T3-E1 cells. Experimental results showed that higher radiation dose resulted in reductions in crystalline nature, denser morphology, lower elastic modulus, less oxygen vacancies and better corrosion resistance. Additionally, 3T3-E1 cells adhered and spread well on the surface of tantalum film with irradiation exposure to 10 kGy. The dense surface morphology, less density of chemical defects and amorphous phase produced by the gamma-ray irradiation played a major role in the improvement of mechanical compatibility, electrochemical stability property along with the cytocompatibility of the tantalum films. In this work, a new bioactive glass was designed, prepared by means of a melt-quenching route and characterized in terms of both thermal properties and biological performance. Adavosertib The main objective was to obtain a novel product with high temperature of crystallization in view of possible thermal treatments, as well as remarkable biological responsiveness. Thermal behavior was investigated by heating microscopy, differential thermal analysis (DTA) and sintering tests. The glass displayed a very high crystallization temperature and the samples remained completely amorphous after sintering. Bioactivity was evaluated by means of Simulated Body Fluid (SBF) assay, which is a widely used method to preliminary investigate samples' reactivity in vitro; the glass showed a strong apatite forming ability. Additionally, in order to exclude cytotoxic effects, biocompatibility was verified according to ISO standard 10993. Finally, the biological potential of the new glass was tested by using an innovative 3D cellular model, that mimicked the potential clinical application of a given biomaterial. Human bone marrow mesenchymal stem cells (BM-MSCs) were employed to study the performance of bioactive glass granules in such 3D cellular model. The results showed that the bioactive glass supported human BM-MSCs adhesion, colonization and bone differentiation. Thus, this new bioactive glass looks particularly promising for orthopedic applications, bone tissue engineering and regenerative medicine, especially when a thermal treatment is necessary for the production of specific devices. The goal of a biomaterial is to support the bone tissue regeneration process at the defect site and eventually degrade in situ and get replaced with the newly generated bone tissue. Nanocomposite biomaterials are a relatively new class of materials that incorporate a biopolymeric and biodegradable matrix structure with bioactive and easily resorbable fillers which are nano-sized. This article is a review of a few polymeric nanocomposite biomaterials which are potential candidates for bone tissue regeneration. These nanocomposites have been broadly classified into two groups viz. natural and synthetic polymer based. Natural polymer-based nanocomposites include materials fabricated through reinforcement of nanoparticles and/or nanofibers in a natural polymer matrix. Several widely used natural biopolymers, such as chitosan (CS), collagen (Col), cellulose, silk fibroin (SF), alginate, and fucoidan, have been reviewed regarding their present investigation on the incorporation of nanomaterial, biocompatibility, ansical properties, such as pore size, porosity, particle size, and mechanical strength which strongly influences cell attachment, proliferation, and subsequent tissue growth has been covered in this review. This review has been sculptured around a case by case basis of current research that is being undertaken in the field of bone regeneration engineering. The nanofillers induced into the polymeric matrix render important properties, such as large surface area, improved mechanical strength as well as stability, improved cell adhesion, proliferation, and cell differentiation. The selection of nanocomposites is thus crucial in the analysis of viable treatment strategies for bone tissue regeneration for specific bone defects such as craniofacial defects. The effects of growth factor incorporation on the nanocomposite for controlling new bone generation are also important during the biomaterial design phase. HYPOTHESIS Bimetallic nanoparticles have continued to attract interest as drug delivery systems in cancer therapy even though their nature of interaction with small molecules is limited. Currently, many delivery systems based on monometallic nanoparticles are being fabricated for loading of drugs, thus prompting the need to explore and get more understanding of dendritic bimetallic nanostructure-drug interaction. EXPERIMENTS The bimetallic gold-core palladium-dendritic shell nanoparticles (Au@PdNDs) were synthesized by hot injection method and stabilized with methoxy polyethylene glycol thiol (mPEG-SH). An anti-cancer drug, doxorubicin (DOX) was conjugated to the bimetallic nanodendrites leading to the formation of DOX/Au@PdNDs.PEG complex. We used TEM, FTIR, and zeta-potential to study the drug-nanodendrites interaction. The effect of DOX binding and release capacity with regards to pH, adsorption kinetics, solvent polarity, isotherms and temperature on Au@PdNDs.PEG were investigated. FINDINGS The results showed a spontaneous heterogeneous binding of DOX on the Au@PdNDs.PEG surfaces and time-dependent loading capacity of ~90% maximum adsorption within 24 h. Moreover, the experimental results showed that the adsorption isotherm data fitted well with the Freundlich model and a pseudo-second order adsorption kinetics. The desorption of DOX was triggered under simulated tumor microenvironmental conditions and should open new opportunities for potential multi stimuli-responsive drug delivery applications. Targeted cancer therapy facilitates localizing the action of chemotherapeutic drugs at the tumor site enhancing the therapeutic efficacy and reducing the side effects to the healthy cells. The homing property of mesenchymal stem cells (MSCs), towards the tumor tissues makes them a potential cell-based delivery system for targeted cancer therapy. Along with chemotherapy, hyperthermia has gained interest as a treatment modality of cancer due to the higher sensitivity of the cancer cells towards heat and also due to its action on tumor cells to enhance sensitization towards chemotherapy or radiotherapy. In the current study, we have shown the multifaceted application of magnetic nanoparticles (MNPs) as a drug delivery vehicle to deliver anti-cancer drug paclitaxel and also as an inducer for magnetic hyperthermia under alternating magnetic field. The combined approach of paclitaxel loaded MNPs and hyperthermia demonstrated enhanced therapeutic efficacy as compared to any single therapy. Further, we have employed MSCs as carrier for these drugs loaded MNPs to achieve targeted and uniform distribution of the MNPs at the tumor site.

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