3D electrospinning used in medical materials

Electrospinning (ES) is an interesting and efficient technique for biomedical use. This is a method used for the fabrication of polymer fibers used in tissue engineering (TE). The electrospun nano- and microfibers biomaterial, called scaffolds, are also used for regenerative medicine. The aim of the present mini-review is to present methods used to fabricate 3D fibers by electrospinning and their applications in TE. Also, discussed here are issues regarding the electrospinning limitations and research challenges

A Valepotriate Fraction of Valeriana glechomifolia Shows Sedative and Anxiolytic Properties and Impairs Recognition But Not Aversive Memory in Mice

Plants of the genus Valeriana (Valerianaceae) are used in traditional medicine as a mild sedative, antispasmodic and tranquilizer in many countries. This study was undertaken to explore the neurobehavioral effects of systemic administration of a valepotriate extract fraction of known quantitative composition of Valeriana glechomifolia (endemic of southern Brazil) in mice. Adult animals were treated with a single intraperitoneal injection of valepotriate fraction (VF) in the concentrations of 1, 3 or 10 mg kg−1, or with vehicle in the pre-training period before each behavioral test. During the exploration of an open field, mice treated with 10 mg kg−1 of VF showed reduced locomotion and exploratory behavior. Although overall habituation sessions for locomotion and exploratory behavior among vehicle control and doses of VF were not affected, comparison between open-field and habituation sessions within each treatment showed that VF administration at 1 and 10 mg kg−1 impaired habituation. In the elevated plus-maze test, mice treated with VF (10 mg kg−1) showed a significant increase in the percentage of time spent in the open arms without significant effects in the number of total arm entries. VF at 3 mg kg−1 produced an impairment of novel-object recognition memory. In contrast, VF did not affect fear-related memory assessed in an inhibitory avoidance task. The results indicate that VF can have sedative effects and affect behavioral parameters related to recognition memory

Production and characterization of magnetic Fe3O4 nanoparticles coated with PCL for biomedical applications

Currently, magnetic nanoparticles are widely studied with regard to their application in cancer treatment. This study aims to show a straightforward strategy for the production of Fe3O4 nanoparticles (NPs) with biocompatible surface modifications with polycaprolactone (PCL) for biomedical purposes. The effects of the polymer coating on the properties of magnetite were evaluated. Crystallinity, morphology, composition, hydrodynamic size and magnetic properties of the produced nanoparticles were analysed via X-ray diffractometry (XRD), Transmission Electron Microscopy (TEM), Fourier-Transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS) and Vibrating Sample Magnetometry (VSM), respectively. The proposed method produced nanoparticles of magnetite with an average size between 9 and 11 nm, with spherical morphology and superparamagnetic properties. Magnetization values were not compromised even when the highest amount of polymer was used in the surface modification. On the other hand, the coating resulted in the decrease of the hydrodynamic size of the composites, indicating greater colloidal stability when the polymer was present. The obtained nanoparticles showed maintenance of significant superparamagneticbehavior, even in the presence of PCL on their surface. This phenomenon would allow for their application as a further optimized vector in hyperthermia cancer treatment, controlled drug delivery and resonance imaging

Caracterização do crescimento de culturas de raízes de Valeriana glechomifolia

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TEOS thin films obtained by plasma polymerization on Ti6Al4V alloys : influence of the deposition pressure on surface properties and cellular response

The modification of surfaces by the application of thin films has been used in the regenerative medicine area to increase the biocompatibility of metal implants. Titanium alloy has been recently used as substrate in poly merization for biomedical application. In this context, silane films were obtained by plasma polymerization in favor of the sol-gel method and the influence of different pressures in obtaining these films by argon plasma polymerization was evaluated from the alkoxysilane precursor tetraethoxysilane (TEOS) on the Ti6Al4V alloy. The morphological characterization of the films was performed by AFM, Profilometry and Spectral Ellipsometry and the chemical composition was analyzed by XPS. The biological behavior was evaluated by analyzing the mitochondrial activity and cellular viability of mesenchymal stem cells. The plasma polymerization process resulted in the deposition of a nanometric Si-based film formed, predominantly, by Si-O and organosilane bonds. The films that were applied on a sanded surface, with lower pressures in the plasma polymerization process, presented a lower layer thickness and wettability than the films obtained on nanotextured surfaces. Considering absorbance values, the Ti6Al4V samples mechanically sanded and deposited by plasma polymerization at 230 µatm presented better cell viability than samples with nanotextured surfaces coated with plasma polymerized film, indicating this material has potential to biomedical application