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Central Nervous System (CNS) can be damaged by a wide range of injuries and disorders which entail permanent disability in some cases. Moreover, CNS repairing process presents some complications. The natural repair mechanism, which consists on the glial scar formation, is triggered by the inflammatory process. Molecules delivered during these processes, inflammation and glial scar formation as well as oxygen and glucose deficiencies due to the injury, create an inhibitory environment for axon regeneration and remyelination which is known as “secondary injury”. Biomaterials are taking up an even more important role in repairing CNS. Physicochemical properties of some ceramic materials have inspired different applications to repair CNS as substrates, electrodes or molecule vehicles. Based on their biocompatibility, capability to neutralize reactive species involved in the inflammatory processes and their versatile processing to obtain scaffolds with different shapes and sizes, ceramics are a succulent offer in nervous tissue engineering. Furthermore, their possibilities have been increased with polymeric-ceramics composites development, which have given rise to new interesting horizon.Existen diferentes tipos de lesiones o desordenes del Sistema Nervioso Central (SNC) que pueden provocar graves secuelas e incluso en algunos casos una discapacidad permanente. Además, el proceso de reparación del SNC tiene algunas complicaciones. El mecanismo natural de reacción a una lesión, el cual consiste en la formación de una cicatriz glial, es desencadenado por un proceso inflamatorio. Las moléculas liberadas durante estos procesos, la inflamación y formación de la cicatriz glial, así como la deficiencia en oxígeno y glucosa debidos a la lesión, crean un ambiente que inhibe la regeneración axonal creando la llamada “lesión secundaria”. Los biomateriales están adquiriendo un papel cada vez más importante en la reparación de SNC. Las propiedades físicoquímicas de algunos materiales han inspirado el uso de los mismos en diferentes aplicaciones para la reparación del SNC como sustratos, electrodos o moléculas transportadoras. En base a su biocompatibilidad, capacidad de neutralizar especies reactivas implicadas en el proceso inflamatorio y a la gran cantidad de posibilidades del procesamiento para obtener andamiajes con diferentes formas y tamaños, los materiales cerámicos suponen una suculenta oferta en la ingeniería del tejido nervioso. Además sus posibilidades han aumentado con el desarrollo de composites polimérico-cerámicos, los cuales ha abierto un nuevo e interesante horizonte en la materia.

TiO2 is able to scavenge reactive oxygen and nitrogen species (ROS and RNS) in the absence of light. The scavenging mechanism has been related to the chemistry of defects (oxygen vacancy reduced oxidation states of Ti) but it is still unknown. This study describes the ROS scavenging activity of different titanium oxide phases and relates their scavenging activities with the Ti4+/Ti3+ molar ratio as well as the band gap value. The Ti5O9 phase, with a mixture of both oxidation states, presented a substantially higher percentage of 2,2-diphenyl-1-picrylhydracyl radicals (DPPHṖ) eliminated per m2 of specific surface area in comparison to phases with predominant oxidation states Ti4+ or Ti3+ such as TiO2 and Ti2O3, respectively. The obtained results indicate that the DPPHṖ scavenging mechanism corresponds to a catalytic process on the Ti5O9 surface which is facilitated by the presence of charges that can easily move through the material. The mobility of charges and electrons in the semiconductor surface, related to the presence of oxidation states Ti4+ and Ti3+ and a small band gap, could create an attractive surface for radical species such as DPPHṖ. This puts forward Ti5O9 as a promising candidate coating for implantable biomedical devices, as an electrode, since it can cushion inflammatory processes which could lead to device encapsulation and, consequently, failure. [ABSTRACT FROM AUTHOR]

This work offers a description of the physico-chemical and electrochemical properties of one of the titanium-based Magneli phases, known as TinO2n−1, for its possible application as an electrode for neural tissue stimulation in neural disorders and Central Nervous System (CNS) injuries. Ti5O9 is one of the less-known Magneli phases that exhibits high electronic conductivity and high chemical and thermal inertness. The material, prepared in a reducing atmosphere by ceramic methods, is composed of a porous surface responsible for most of its properties. Chemical and physical features of the surface were studied with the aim of establishing a relationship between them and the surface electrochemistry. The chemical composition of the surface was studied by XRD and XPS. The topography was studied by AFM and the morphology of the outer side of a fracture was observed by SEM. The conductivity was measured by the four point method in DC finding extremely high values, 9500 S cm−1 at 37 °C. The study of the surface electrochemistry in contact with media, which simulate physiological conditions, was carried out by cyclic voltammetry and EIS. With these measurements the charge injection mechanism has been elucidated, and the charge storage capacity of the material has been determined, finding higher values than those reported for other ceramic electrodes. Finally, cell cultures realised with neural cells were obtained from the cerebral cortex of E18 Wistar rat embryos. They were observed after 4 and 10 DIV and helped in the determination of the biocompatibility of the material. [ABSTRACT FROM AUTHOR]

The photocatalytic behaviours of semiconductive ceramic nanoparticles such as TiO 2 , ZnO, Fe 2 O 3 , and Fe 3 O 4 , have been extensively studied in photocatalysis and photopolymerization, due to their ability to produce radical species under ultraviolet-visible light, and even in dark conditions. In addition, in the form of microparticles, TiO 2 and its Magnéli phases are capable of neutralizing radical species, and a heterogeneous catalytic process has been suggested to explain this property, as it is well known as scavenging activity. Thus, in this study, we demonstrate that these ceramic powders, in the form of microparticles, could be used as photoinitiators in UV polymerization in order to synthesize a hydrogel matrix. Them, embedded ceramic powders could be able to neutralize radical species of physiological media once implanted. The hydrogel matrix would regulate the exchange of free radicals in any media, while the ceramic particles would neutralize the reactive species. Therefore, in this work, the scavenger activities of TiO 2 , ZnO, Fe 2 O 3 , and Fe 3 O 4 microparticles, along with their photoinitiation yield, were evaluated. After photopolymerization, the gel fraction and swelling behaviour were evaluated for each hydrogel produced with different ceramic initiators. Gel fractions were higher than 60%, exhibiting variation in their scavenging activity. Therefore, we demonstrate that ceramic photoinitiators of TiO 2 , ZnO, Fe 2 O 3 , and Fe 3 O 4 can be used to fabricate implantable devices with scavenger properties in order to neutralize radical species involved in inflammatory processes and degenerative diseases.

Introduction: Osteoarthritis (OA) is the most common form of arthritis and can severely affect function and quality of life. Platelet-rich plasma (PRP) is derived from a patient's own blood and has potential as an adjunct to treat OA. However, research has been limited for small joints such as the carpometacarpal (CMC) joint., Clinical Findings: A 65-year-old Caucasian male complained of bilateral wrist and neck pain after a motor vehicle accident. His initial exam noted swelling, tenderness and pain with movement at the bilateral thumb CMC joints and anatomic snuffboxes. However, there was no strength, range of motion or tactile deficits during examination., Outcomes: He was found to have moderate to severe OA bilaterally in his left and right CMC joints seen on computed tomography and magnetic resonance imaging. The patient was initially treated with ultrasound (US)-guided steroid injections but did not experience significant improvement. After careful discussion, the patient chose to undergo US-guided injection of PRP into both joints. Follow-up at six weeks after PRP injection revealed that there was functional improvement in both joints as well as objective improvement via the Mayo Wrist Score survey., Conclusion: US-guided PRP injection can be used as an alternative modality to treat OA of the CMC joints when approaches such as conservative therapy and steroid injections have failed. PRP has not been as well studied as other interventions such as corticosteroid injections, but it may offer less long-term adverse effects and be considered a potential alternative or adjuvant to current treatment modalities., Competing Interests: Conflicts of Interest The authors declare they have no conflicts of interest., (© 2021 HCA Physician Services, Inc. d/b/a Emerald Medical Education.)

In this work, a new family of multiphasic materials composed of the same amount of silica gel and variable amount of three calcium phosphates with very different solubilities, monetite > amorphous calcium phosphate > hydroxyapatite (HAp), was studied. Silicon was added to calcium phosphate to increase bioactivity and osteinductivity. The influence of the HAp/monetite ratio on the material resorption and bone regeneration was investigated in critical bone defects in sheep and was related to their chemical and physical properties. It was concluded that a minimum rate of HAp/monetite is necessary to achieve an appropriate compromise between material resorption and bone regeneration. Above this minimum rate, bone regeneration and material resorbtion did not change significantly. Physical properties such as particle size, specific surface area, porosity, and granulate cohesion played a more critical role on material resorption than the solubility of their components. A huge difference between in vitro solubility and in vivo resorption was observed. It was related to the fastest cellular-mediated resorption of monetite compared to the other components. Computerized axial tomography, histology, histomorphometric, and multiple fluorochrome labeling studies showed a very advanced bone regeneration of the defects when materials with the highest HAp/monetite rate were implanted. It was also demonstrated that all materials induce bone formation and vascularization.

Objectives: First ribs bear information about thorax morphology and are usually well preserved, compared to other ribs, in bone/fossil samples. Several studies have addressed ontogeny of the first rib by studying changes in bone microanatomy and rib morphology separately, but no studies have combined both approaches to study how internal and external changes covary during ontogeny. The aim of this project is to fill this gap in our knowledge., Materials and Methods: We applied 3D geometric morphometrics of sliding semilandmarks to 14 first ribs of Homo sapiens to quantify rib curvature and mid-shaft cross-section outline. Ontogenetic variation was addressed throughout a principal component analysis (PCA). Additionally, we made histological sections at the mid-shaft of the same ribs and studied tissue matrix composition and compartmentalization. Finally, we performed partial least squares (PLS) and regression analyses to study covariation between rib morphology and compartmentalization variables., Results: PCA shows that first ribs increase their curvature over the course of ontogeny and the rib midshaft becomes less rounded during ontogeny. In addition, the sternal end becomes more medially oriented during ontogeny and the relative head-tubercle distance becomes longer. Compartmentalization shows a decrease in the area occupied by mineralized tissues and an increase in the area occupied by non-mineralized tissues over the course of ontogeny, which covaries with mid-shaft cross-section shape., Conclusions: Our results show detailed variation in rib morphology along with histological changes in bone tissue compartmentalization and, for the first time, the correlation between the two. This could be related to muscle attachments on the 1st rib and also to changes in breathing mode, from diaphragmatic in perinatals to pulmonary in adults, which could also have implications for understanding thorax evolution., (© 2017 Wiley Periodicals, Inc.)

This work offers a description of the physico-chemical and electrochemical properties of one of the titanium-based Magneli phases, known as Ti n O 2n-1 , for its possible application as an electrode for neural tissue stimulation in neural disorders and Central Nervous System (CNS) injuries. Ti 5 O 9 is one of the less-known Magneli phases that exhibits high electronic conductivity and high chemical and thermal inertness. The material, prepared in a reducing atmosphere by ceramic methods, is composed of a porous surface responsible for most of its properties. Chemical and physical features of the surface were studied with the aim of establishing a relationship between them and the surface electrochemistry. The chemical composition of the surface was studied by XRD and XPS. The topography was studied by AFM and the morphology of the outer side of a fracture was observed by SEM. The conductivity was measured by the four point method in DC finding extremely high values, 9500 S cm -1 at 37 °C. The study of the surface electrochemistry in contact with media, which simulate physiological conditions, was carried out by cyclic voltammetry and EIS. With these measurements the charge injection mechanism has been elucidated, and the charge storage capacity of the material has been determined, finding higher values than those reported for other ceramic electrodes. Finally, cell cultures realised with neural cells were obtained from the cerebral cortex of E18 Wistar rat embryos. They were observed after 4 and 10 DIV and helped in the determination of the biocompatibility of the material.

Aiming to characterize the use of biomaterials in cancer therapy, we took advantage of the n-type semiconductor properties, which upon irradiation excite their electrons into the conduction band to induce photoelectrochemical reactions generating oxygen reactive species (ROS). Indeed, photoactivated TiO(2) nanoparticles have been shown to kill in vitro either bacteria or tumor cells in culture following UV irradiation, as a consequence of the ROS levels generated; the killing was highly effective although devoid of specificity. In this report, we have directed the TiO(2) nanoparticles to particular targets by coupling them to the monoclonal antibody (mAb) Nilo1, recognizing a surface antigen in neural stem cells within a cell culture, to explore the possibility of making this process specific. TiO(2) nanoparticles generated with particular rutile/anatase ratios were coupled to Nilo1 antibody and the complexes formed were highly stable. The coupled antibody retained the ability to identify neural stem cells and upon UV irradiation, the TiO(2) nanoparticles were activated, inducing the selective photokilling of the antibody-targeted cells. Thus, these data indicate that antibody-TiO(2) complexes could be used to specifically remove target cell subpopulations, as demonstrated with neural stem cells. The possible applications in cancer therapy are discussed.