Tuning Nanopore Diameter of Titanium Surfaces to Improve Human Gingival Fibroblast Response

The aim of this study was to determine the optimal nanopore diameter of titanium nanostructured surfaces to improve human gingival fibroblast (hGF) response, with the purpose of promoting gingiva integration to dental implant abutments. Two TiO2 nanoporous groups with different diameters (NP-S ~48 nm and NP-B ~74 nm) were grown on Ti foils using an organic electrolyte containing fluoride by electrochemical oxidation, varying the applied voltage and the interelectrode spacing. The surfaces were characterized by scanning electron microscope (SEM), atomic force microscopy (AFM), and contact angle. The hGF were cultured onto the different surfaces, and metabolic activity, cytotoxicity, cell adhesion, and gene expression were analyzed. Bigger porous diameters (NP-B) were obtained by increasing the voltage used during anodization. To obtain the smallest diameter (NP-S), apart from lowering the voltage, a lower interelectrode spacing was needed. The greatest surface area and number of peaks was found for NP-B, despite these samples not being the roughest as defined by Ra. NP-B had a better cellular response compared to NP-S. However, these effects had a significant dependence on the cell donor. In conclusion, nanoporous groups with a diameter in the range of 74 nm induce a better hGF response, which may be beneficial for an effective soft tissue integration around the implant

Nanostructured Titanium for Improved Endothelial Biocompatibility and Reduced Platelet Adhesion in Stent Applications

Although coronary stents have improved the early and long-term consequences of arterial lesions, the prevention of restenosis and late stent thrombosis is key to prevent a new obstruction of the vessel. Here we aimed at improving the tissue response to stents through surface modification. For that purpose, we used two different approaches, the use of nanostructuration by electrochemical anodization and the addition of a quercitrin (QR) coating to the Ti surface. Four surfaces (Ti, NN, TiQR and NNQR) were characterized by atomic force microscopy, scanning electronic microscopy and contact angle analysis and QR content was evaluated by fluorescent staining. Cell adhesion, cytotoxicity, metabolic activity and nitric oxide (NO) production was evaluated on primary human umbilical cord endothelial cells (HUVECs). Platelet adhesion, hemolysis rate and Staphylococcus epidermidis CECT 4184 adhesion at 30 min were analyzed. Nanostructuration induced an increase on surface roughness, and QR coating decreased the contact angle. All surfaces were biocompatible, with no hemolysis rate and lower platelet adhesion was found in NN surfaces. Finally, S. epidermidis adhesion was lower on TiQR surfaces compared to Ti. In conclusion, our results suggest that NN structuration could improve biocompatibility of bare metal stents on endothelial cells and reduce platelet adhesion. Moreover, QR coating could reduce bacterial adhesion

Multifunctional Properties of Quercitrin-Coated Porous Ti-6Al-4V Implants for Orthopaedic Applications Assessed In Vitro

(1) One strategy to improve the outcome of orthopedic implants is to use porous implants with the addition of a coating with an antibacterial biomolecule. In this study, we aimed to produce and test the biocompatibility, the osteopromotive (both under normal conditions and under a bacterial challenge with lipopolysaccharide (LPS)) and antibacterial activities of a porous Ti-6Al-4V implant coated with the flavonoid quercitrin in vitro. (2) Porous Ti-6Al-4V implants were produced by 3D printing and further functionalized with quercitrin by wet chemistry. Implants were characterized in terms of porosity and mechanical testing, and the coating with quercitrin by fluorescence staining. Implant biocompatibility and bioactivity was tested using MC3T3-E1 preosteoblasts by analyzing cytotoxicity, cell adhesion, osteocalcin production, and alkaline phosphatase (ALP) activity under control and under bacterial challenging conditions using lipopolysaccharide (LPS). Finally, the antibacterial properties of the implants were studied using Staphylococcus epidermidis by measuring bacterial viability and adhesion. (3) Porous implants showed pore size of about 500 µm and a porosity of 52%. The coating was homogeneous over all the 3D surface and did not alter the mechanical properties of the Young modulus. Quercitrin-coated implants showed higher biocompatibility, cell adhesion, and osteocalcin production compared with control implants. Moreover, higher ALP activity was observed for the quercitrin group under both normal and bacterial challenging conditions. Finally, S. epidermidis live/dead ratio and adhesion after 4 h of incubation was lower on quercitrin implants compared with the control. (4) Quercitrin-functionalized porous Ti-6Al-4V implants present a great potential as an orthopedic porous implant that decreases bacterial adhesion and viability while promoting bone cell growth and differentiation

Lower activation in the right frontoparietal network during a counting Stroop task in a cocaine-dependent group

Dysregulation in cognitive control networks may mediate core characteristics of drug addiction. Cocaine dependence has been particularly associated with lowactivation in the frontoparietal regions during conditions requiring decision making and cognitive control. This functional magnetic resonance imaging (fMRI) study aimed to examine differential brain-related activation to cocaine addiction during an inhibitory control paradigm, the “Counting” Strooptask, given the uncertainties of previous studies using positron emission tomography. Sixteen comparison men and 16 cocaine-dependent men performed a cognitive “Counting” Strooptask in a 1.5 T Siemens Avanto. The cocaine-dependent patient group and the control group were matched for age, level of education and general intellectual functioning. Groups did not differ in terms of the interference measures deriving from the countingStrooptask. Moreover, the cocaine-dependentgroup showed loweractivation in the right inferior frontal gyrus, the right inferior parietal gyrus and the right superior temporal gyrus than the control group. Cocaine patients did not show any brain area with increased activation when compared with controls. In short, Stroop-interference was accompanied by loweractivation in the rightfrontoparietalnetwork in cocaine-dependent patients, even in the absence of inter-group behavioral differences. Our study is the first application of acountingStrooptask using fMRI to study cocaine dependence and yields results that corroborate the involvement of afrontoparietalnetwork in the neural changes associated with attentional interference deficits in cocaine-dependent men

Right parietal hypoactivation in a cocaine-dependent group during a verbal working memory task

It has been suggested that cocaine addiction affects the engagement of the frontoparietal networks in executive functions, such as attention and workingmemory. Thus, our objective was to investigate brain differences between cocaine-dependent subjects and healthy controls during the performance ofaverbalworkingmemorytask. Nineteen comparison men and nineteen cocaine-dependent men performed a 2-back task. Data were acquired on a 1.5-T Siemens Avanto. Image processing and statistical analyses were carried out using SPM5; Biological Parametric Mapping (BPM) was used for further morphometric and correlation analyses. No performance differences were found between groups. However, the dorsal part of the right inferior parietal cortex (BA 40) was less activated in thecocaine-dependentgroup. Cocaine patients did not overactive any brain area when compared with controls. Our results show reduced activation in the brain areas related to the attention system incocaine-dependent men while performing averbalworkingmemorytask. Chronic cocaine use may affect the attentional system in the rightparietal lobe, making patients more prone to attentional deficits.This study was supported by grants from FEPAD (Fundación para el Estudio, Prevención y Asistencias a la Drogodependencia), from the“National Plan of Drugs” (Plan Nacional de Drogas), and from the BRAINGLOT, a Spanish Research Network on Bilingualism and Cognitive Neuroscience (Consolider-Ingenio 2010 Programme, Spanish Ministry of Science and Education, CSD2007-00012). Moreover, the study was supported by a Ph.D. fellowship from “Universitat Jaume I” of Castellón (PREDOC/2007/13

Reaching consensus on communication of critical laboratory results using a collective intelligence method

There is no consensus in the literature about what analytes or values should be informed as critical results and how they should be communicated. The main aim of this project is to establish consensual standards of critical results for the laboratories participating in the study. Among the project's secondary objectives, establishing consensual procedures for communication can be highlighted. Consensus was reached among all participating laboratories establishing the basis for the construction of the initial model put forward for consensus in conjunction with the clinicians. A real-time Delphi, methodologyPostprint (author's final draft

Reaching consensus on communication of critical laboratory results using a collective intelligence method

There is no consensus in the literature about what analytes or values should be informed as critical results and how they should be communicated. The main aim of this project is to establish consensual standards of critical results for the laboratories participating in the study. Among the project's secondary objectives, establishing consensual procedures for communication can be highlighted. Consensus was reached among all participating laboratories establishing the basis for the construction of the initial model put forward for consensus in conjunction with the clinicians. A real-time Delphi, methodolog