Osteoblasts-derived exosomes as potential novel communicators in particle-induced periprosthetic osteolysis.

The inflammatory response to wear particles derived from hip prothesis is considered a hallmark of periprosthetic osteolysis, which can ultimately lead to the need for revision surgery. Exosomes (Exos) have been associated with various bone pathologies, and there is increasing recognition in the literature that they actively transport molecules throughout the body. The role of wear particles in osteoblast-derived Exos is unknown, and the potential contribution of Exos to osteoimmune communication and periprosthetic osteolysis niche is still in its infancy.

The secretome of macrophages has a differential impact on spinal cord injury recovery according to the polarization protocol.

Introduction: The inflammatory response after spinal cord injury (SCI) is an important contributor to secondary damage. Infiltrating macrophages can acquire a spectrum of activation states, however, the microenvironment at the SCI site favors macrophage polarization into a pro-inflammatory phenotype, which is one of the reasons why macrophage transplantation has failed.

Methods: In this study, we investigated the therapeutic potential of the macrophage secretome for SCI recovery.

Meningococcal Septic Oligoarthritis: An Unusual Presentation Revealing Concurrent Multiple Myeloma.

Meningococcal invasive disease is rare in immunocompetent hosts but may occur in patients with risk factors. Septic arthritis is an uncommon form of presentation and is usually due to surgical colonization or hematogenous dissemination. We present a case of a 73-year-old woman, who recently underwent knee replacement surgery, presenting with right knee and left shoulder pain, swelling, and reduced range of motion.

Exploring Suspected Diagnoses in Elderly Patients: A Case Study of Potential Necrotizing Otitis Externa.

Necrotizing otitis externa (NOE) is a rare invasive infection affecting the EAC and the base of the skull. This condition is more prevalent in the elderly, diabetics, and immunocompromised individuals, often attributed to the bacterium . In this case report, we present the clinical scenario of a 90-year-old woman with a history of diabetes and epilepsy.

Titanium dioxide nanoparticles affect osteoblast-derived exosome cargos and impair osteogenic differentiation of human mesenchymal stem cells.

Titanium (Ti) and its alloys are the most widely used metallic biomaterials in total joint replacement; however, increasing evidence supports the degradation of its surface due to corrosion and wear processes releasing debris (ions, and micro and nanoparticles) and contribute to particle-induced osteolysis and implant loosening. Cell-to-cell communication involving several cell types is one of the major biological processes occurring during bone healing and regeneration at the implant-bone interface. In addition to the internal response of cells to the uptake and intracellular localization of wear debris, a red flag is the ability of titanium dioxide nanoparticles (mimicking wear debris) to alter cellular communication with the tissue background, disturbing the balance between osseous tissue integrity and bone regenerative processes.

Osteoblastic response to biomaterials surfaces: Extracellular matrix proteomic analysis.

The cellular response to surfaces is mediated, among other factors, by the extracellular matrix (ECM). However, little is known about the ECM proteome during mineralization. Our objective was to compare the ECM composition formed by osteoblast on different materials surfaces with proteomic analysis.

Levetiracetam treatment leads to functional recovery after thoracic or cervical injuries of the spinal cord.

Spinal cord injury (SCI) leads to dramatic impairments of motor, sensory, and autonomic functions of affected individuals. Following the primary injury, there is an increased release of glutamate that leads to excitotoxicity and further neuronal death. Therefore, modulating glutamate excitotoxicity seems to be a promising target to promote neuroprotection during the acute phase of the injury.

Evaluation of ASCs and HUVECs Co-cultures in 3D Biodegradable Hydrogels on Neurite Outgrowth and Vascular Organization.

Vascular disruption following spinal cord injury (SCI) decisively contributes to the poor functional recovery prognosis facing patients with the condition. Using a previously developed gellan gum hydrogel to which the adhesion motif GRGDS was grafted (GG-GRGDS), this work aimed to understand the ability of adipose-derived stem cells (ASCs) to impact vascular organization of human umbilical vein endothelial cells (HUVECs), and how this in turn affects neurite outgrowth of dorsal root ganglia (DRG) explants. Our data shows that culturing these cells together lead to a synergistic effect as showed by increased stimulation of neuritogenesis on DRG.

A Comparative Study between Knocked-Down Aligned Carbon Nanotubes and Buckypaper-Based Strain Sensors.

Carbon nanotubes (CNTs) are one of the most promising materials in sensing applications due to their electrical and mechanical properties. This paper presents a comparative study between CNT Buckypaper (BP) and aligned CNT-based strain sensors. The Buckypapers were produced by vacuum filtration of commercial CNTs dispersed in two different solvents, N,N-Dimethylformamide (DMF) and ethanol, forming freestanding sheets, which were cut in 10 × 10 mm squares and transferred to polyimide (PI) films.

Exposure effects of endotoxin-free titanium-based wear particles to human osteoblasts.

Titanium-based materials are widely employed by the biomedical industry in orthopedic and dental implants. However, when placed into the human body, these materials are highly susceptible to degradation processes, such as corrosion, wear, and tribocorrosion. As a consequence, metallic ions or particles (debris) may be released, and although several studies have been conducted in recent years to better understand the effects of their exposure to living cells, a consensual opinion has not yet been obtained.

Vanadium ionic species from degradation of Ti-6Al-4V metallic implants: In vitro cytotoxicity and speciation evaluation.

Among the metallic materials used in biomedical industry, the most common choice for orthopedics and dental implants is titanium (Ti) and its alloys, mainly due to their superior corrosion and tribocorrosion resistance and biocompatibility. Under different conditions in vivo, such as different pH levels, composition of body fluid and mechanical loads, metallic materials may suffer from degradation, resulting in the release of undesired wear particles and ions. In particular, the Ti-6Al-4V system represents almost half of the production of Ti as a biomaterial and many concerns have been raised about titanium, aluminum and vanadium ions releasing.

High-Resolution Seismocardiogram Acquisition and Analysis System.

Several devices and measurement approaches have recently been developed to perform ballistocardiogram (BCG) and seismocardiogram (SCG) measurements. The development of a wireless acquisition system (hardware and software), incorporating a novel high-resolution micro-electro-mechanical system (MEMS) accelerometer for SCG and BCG signals acquisition and data treatment is presented in this paper. A small accelerometer, with a sensitivity of up to 0.

The Role of Biomaterials as Angiogenic Modulators of Spinal Cord Injury: Mimetics of the Spinal Cord, Cell and Angiogenic Factor Delivery Agents.

Spinal cord injury (SCI) represents an extremely debilitating condition for which no efficacious treatment is available. One of the main contributors to the inhospitable environment found in SCI is the vascular disruption that happens at the moment of injury that compromises the blood-spinal cord barrier (BSCB) and triggers a cascade of events that includes infiltration of inflammatory cells, ischemia and intraparenchymal hemorrhage. Due to the unsatisfactory nature of revascularization following SCI, restoring vascular perfusion and the BSCB seems an interesting way of modulating the lesion environment into a regenerative phenotype, with a potential increase in functional recovery.

Improved tribocorrosion performance of bio-functionalized TiO nanotubes under two-cycle sliding actions in artificial saliva.

After insertion into bone, dental implants may be subjected to tribocorrosive conditions resulting in the release of metallic ions and solid wear debris, which can induce to peri-implant inflammatory reactions accompanied by bone loss, and ultimately implant loosening. Despite the promising ability of TiO nanotubes (NTs) to improve osseointegration and avoid infection-related failures, the understanding of their degradation under the simultaneous action of wear and corrosion (tribocorrosion) is still very limited. This study aims, for the first time, to study the tribocorrosion behavior of bio-functionalized TiO NTs submitted to two-cycle sliding actions, and compare it with conventional TiO NTs.

αvβ3 and α5β1 integrin-specific ligands: From tumor angiogenesis inhibitors to vascularization promoters in regenerative medicine?

Integrins are cell adhesion receptors predominantly important during normal and tumor angiogenesis. A sequence present on several extracellular matrix proteins composed of Arg-Gly-Asp (RGD) has attracted attention due to its role in cell adhesion mediated by integrins. The development of ligands that can bind to integrins involved in tumor angiogenesis and brake disease progression has resulted in new investigational drug entities reaching the clinical trial phase in humans.

Bio-camouflage of anatase nanoparticles explored by in situ high-resolution electron microscopy.

While titanium is the metal of choice for most prosthetics and inner body devices due to its superior biocompatibility, the discovery of Ti-containing species in the adjacent tissue as a result of wear and corrosion has been associated with autoimmune diseases and premature implant failures. Here, we utilize the in situ liquid cell transmission electron microscopy (TEM) in a liquid flow holder and graphene liquid cells (GLCs) to investigate, for the first time, the in situ nano-bio interactions between titanium dioxide nanoparticles and biological medium. This imaging and spectroscopy methodology showed the process of formation of an ionic and proteic bio-camouflage surrounding Ti dioxide (anatase) nanoparticles that facilitates their internalization by bone cells.

Combatting resistance in intensive care: the multimodal approach of the Spanish ICU "Zero Resistance" program.

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2015 and co-published as a series in Critical Care. Other articles in the series can be found online at http://ccforum.com/series/annualupdate2015.

Anodization Mechanism on SiC Nanoparticle Reinforced Al Matrix Composites Produced by Power Metallurgy.

Specimens of aluminum-based composites reinforced by silicon carbide nanoparticles (Al/SiC) produced by powder metallurgy (PM) were anodized under voltage control in tartaric-sulfuric acid (TSA). In this work, the influence of the amount of SiC on the film growth during anodizing was investigated. The current density time response and the morphology of the porous alumina film formed at the composite surface are compared to those concerning a commercial aluminum alloy (AA1050) anodized under the same conditions.

How do titanium and Ti6Al4V corrode in fluoridated medium as found in the oral cavity? An in vitro study.

The purpose of this work was to evaluate the corrosion of commercially pure (CP) titanium and Ti6Al4V in vitro at different F(-) concentrations regularly found in the oral cavity by using different electrochemical tests and surface analysis techniques. electrochemical impedance spectroscopy (EIS), open circuit potential (OCP) and potentiodynamic polarization tests were associated to advanced characterization techniques such as SEM, EDS, AFM, ICP-MS and XPS. OCP tests revealed a higher reactivity of both CP titanium and Ti6Al4V at 12,300 ppm F(-) concentration than that recorded at 227 ppm F(-).

Influence of the casting processing route on the corrosion behavior of dental alloys.

Casting in the presence of oxygen may result in an improvement of the corrosion performance of most alloys. However, the effect of corrosion on the casting without oxygen for dental materials remains unknown. The aim of this study was to investigate the influence of the casting technique and atmosphere (argon or oxygen) on the corrosion behavior response of six different dental casting alloys.

Implantable flexible pressure measurement system based on inductive coupling.

One of the currently available treatments for aortic aneurysms is endovascular aneurysm repair (EVAR). In spite of major advances in the operating techniques, complications still occur and lifelong surveillance is recommended. In order to reduce and even eliminate the commonly used surveillance imaging exams, as well as to reduce follow-up costs, new technological solutions are being pursued.

Mechanical and chemical analyses across dental porcelain fused to CP titanium or Ti6Al4V.

The aim of this study was to evaluate the evolution of mechanical properties and chemical variation across veneering dental porcelain fused to different titanium-based substrates. Test samples were synthesized by fusing dental feldspar-based porcelain onto commercially pure titanium grade II or Ti6Al4V alloy. Samples were cross-sectioned at angles of 10 and 90° to the interface plane.

Are new TiNbZr alloys potential substitutes of the Ti6Al4V alloy for dental applications? An electrochemical corrosion study.

The main aim of this work was to assess the electrochemical behavior of new Ti35Nb5Zr and Ti35Nb10Zr alloys in artificial saliva at 37 °C to verify if they are indicated to be used as biomaterials in dentistry as alternatives to Ti6Al4V alloys in terms of corrosion protection efficiency of the material. Electrochemical impedance spectroscopy (EIS) experiments were carried out for different periods of time (0.5-216 h) in a three-electrode cell, where the working electrode (Ti alloys) was exposed to artificial saliva at 37 °C.

Corrosion behaviour of titanium in the presence of Streptococcus mutans.

Objective: The main aim of this in vitro study was to evaluate the influence of Streptococcus mutans on the corrosion of titanium.

Methods: S. mutans biofilms were formed on commercially pure titanium (CP-Ti) square samples (10mm×10mm×1mm) using a culture medium enriched with sucrose.

Influence of the processing route of porcelain/Ti-6Al-4V interfaces on shear bond strength.

This study aims at evaluating the two-fold effect of initial surface conditions and dental porcelain-to-Ti-6Al-4V alloy joining processing route on the shear bond strength. Porcelain-to-Ti-6Al-4V samples were processed by conventional furnace firing (porcelain-fused-to-metal) and hot pressing. Prior to the processing, Ti-6Al-4V cylinders were prepared by three different surface treatments: polishing, alumina or silica blasting.