Mechanics Predicts Effective Critical-Size Bone Regeneration Using 3D-Printed Bioceramic Scaffolds.

Background: 3D-printed bioceramic scaffolds have gained popularity due to their controlled microarchitecture and their proven biocompatibility. However, their high brittleness makes their surgical implementation complex for weight-bearing bone treatments. Thus, they would require difficult-to-instrument rigid internal fixations that limit a rigorous evaluation of the regeneration progress through the analysis of mechanic-structural parameters.

Robocasting and Laser Micromachining of Sol-Gel Derived 3D Silica/Gelatin/β-TCP Scaffolds for Bone Tissue Regeneration.

The design and synthesis of sol-gel silica-based hybrid materials and composites offer significant benefits to obtain innovative biomaterials with controlled porosity at the nanostructure level for applications in bone tissue engineering. In this work, the combination of robocasting with sol-gel ink of suitable viscosity prepared by mixing tetraethoxysilane (TEOS), gelatin and β-tricalcium phosphate (β-TCP) allowed for the manufacture of 3D scaffolds consisting of a 3D square mesh of interpenetrating rods, with macropore size of 354.0 ± 17.

Structural optimization of 3D-printed patient-specific ceramic scaffolds for in vivo bone regeneration in load-bearing defects.

Tissue engineering has recently gained popularity as an alternative to autografts to stimulate bone tissue regeneration through structures called scaffolds. Most of the in vivo experiments on long-bony defects use internally-stabilized generic scaffolds. Despite the wide variety of computational methods, a standardized protocol is required to optimize ceramic scaffolds for load-bearing bony defects stabilized with flexible fixations.

Response of osteoblasts and preosteoblasts to calcium deficient and Si substituted hydroxyapatites treated at different temperatures.

Hydroxyapatite (HA) is a calcium phosphate bioceramic widely used for bone grafting and augmentation purposes. The biological response of HA can be improved through chemical and microstructural modifications, as well as by manufacturing it as macroporous implants. In the present study, calcium deficient hydroxyapatite (CDHA) and Si substituted hydroxyapatite (SiHA) macroporous scaffolds have been prepared by robocasting.

Fabrication of novel Si-doped hydroxyapatite/gelatine scaffolds by rapid prototyping for drug delivery and bone regeneration.

Porous 3-D scaffolds consisting of gelatine and Si-doped hydroxyapatite were fabricated at room temperature by rapid prototyping. Microscopic characterization revealed a highly homogeneous structure, showing the pre-designed porosity (macroporosity) and a lesser in-rod porosity (microporosity). The mechanical properties of such scaffolds are close to those of trabecular bone of the same density.

Effect of Polymer Infiltration on the Flexural Behavior of β-Tricalcium Phosphate Robocast Scaffolds.

The influence of polymer infiltration on the flexural strength and toughness of β-tricalcium phosphate (β-TCP) scaffolds fabricated by robocasting (direct-write assembly) is analyzed. Porous structures consisting of a tetragonal three-dimensional lattice of interpenetrating rods were impregnated with biodegradable polymers (poly(lactic acid) (PLA) and poly(ε-caprolactone) (PCL)) by immersion of the structure in a polymer melt. Infiltration increased the flexural strength of these model scaffolds by a factor of 5 (PCL) or 22 (PLA), an enhancement considerably greater than that reported for compression strength of analogue materials.

Sex differences in patients with systemic lupus erythematosus from Northwest Spain.

To further establish potential differences according to sex in systemic lupus erythematosus (SLE) patients from Southern Europe. We assessed clinical and epidemiological data of patients diagnosed with SLE according to the 1982 American College of Rheumatology classification criteria at the single hospital for a well-defined population of Northwest Spain, between 1987 and 2006. Prevalence in December 2006 and age-standardized incidence rates in the whole period were estimated.

Reinforcing bioceramic scaffolds with in situ synthesized ε-polycaprolactone coatings.

In situ ring-opening polymerization of ε-caprolactone (ε-CL) was performed to coat β-tricalcium phosphate (β-TCP) scaffolds fabricated by robocasting in order to enhance their mechanical performance while preserving the predesigned macropore architecture. Concentrated colloidal inks prepared from β-TCP commercial powders were used to fabricate porous structures consisting of a three-dimensional mesh of interpenetrating rods. Then, ε-CL was in situ polymerized within the ceramic structure using a lipase as catalyst and toluene as solvent, to obtain a highly homogeneous coating and full impregnation of in-rod microporosity.

Impregnation of β-tricalcium phosphate robocast scaffolds by in situ polymerization.

Ring-opening polymerization of ε-caprolactone (ε-CL) and L-lactide (LLA) was performed to impregnate β-tricalcium phosphate (β-TCP) scaffolds fabricated by robocasting. Concentrated colloidal inks prepared from β-TCP commercial powders were used to fabricate porous structures consisting of a 3D mesh of interpenetrating rods. ε-CL and LLA were in situ polymerized within the ceramic structure by using a lipase and stannous octanoate, respectively, as catalysts.

Late-onset systemic lupus erythematosus in Northwestern Spain: differences with early-onset systemic lupus erythematosus and literature review.

To further investigate into the epidaemiology of systemic lupus erythematosus (SLE) in Southern Europe, we have assessed the incidence, clinical spectrum and survival of patients diagnosed with late-onset SLE (age ≥ 50 years) according to the 1982 American College of Rheumatology (ACR) classification criteria at the single hospital for a well-defined population of Lugo, Northwestern (NW) Spain. Between January 1987 and December 2006, 51 (39.3%) of the 150 patients diagnosed as having SLE fulfilled definitions for late-onset SLE.

Biological properties of solid free form designed ceramic scaffolds with BMP-2: in vitro and in vivo evaluation.

Porous ceramic scaffolds are widely studied in the tissue engineering field due to their potential in medical applications as bone substitutes or as bone-filling materials. Solid free form (SFF) fabrication methods allow fabrication of ceramic scaffolds with fully controlled pore architecture, which opens new perspectives in bone tissue regeneration materials. However, little experimentation has been performed about real biological properties and possible applications of SFF designed 3D ceramic scaffolds.

Label-free magnetic resonance imaging to locate live cells in three-dimensional porous scaffolds.

Porous scaffolds are widely tested materials used for various purposes in tissue engineering. A critical feature of a porous scaffold is its ability to allow cell migration and growth on its inner surface. Up to now, there has not been a method to locate live cells deep inside a material, or in an entire structure, using real-time imaging and a non-destructive technique.

Systemic lupus erythematosus in northwestern Spain: a 20-year epidemiologic study.

To further investigate the epidemiology of systemic lupus erythematosus (SLE) in southern Europe, we assessed the incidence, prevalence, clinical spectrum of the disease, flares, and survival of patients diagnosed with SLE in the Lugo region of northwestern Spain. Between January 1987 and December 2006, 150 Lugo residents were diagnosed as having SLE according to the 1982 American College of Rheumatology criteria for the classification of SLE. Women outnumbered men (127 [84.

Improving the compressive strength of bioceramic robocast scaffolds by polymer infiltration.

The effect of polymer infiltration on the compressive strength of β-tricalcium phosphate (TCP) scaffolds fabricated by robocasting (direct write assembly) is analyzed in this work. Porous structures consisting of a tetragonal three-dimensional mesh of interpenetrating rods were fabricated from concentrated TCP inks with suitable viscoelastic properties. Biodegradable polymers (polylactic acid (PLA) and poly(ε-caprolactone) (PCL)) were infiltrated into selected scaffolds by immersion of the structure in a polymer melt.

[Dorsal sensory level as a false localizing sign in cervical myelopathy].

Introduction: Cervical myelopathy is a common disorder of the spinal cord. The most frequent symptoms are muscle weakness and spasticity starting in the legs. Occasionally the sensory levels are several spinal cord segments below the cervical lesion which makes diagnosis difficult.

[Wallenberg syndrome: a review of 25 cases].

Introduction: Wallenberg's syndrome is one of the most common clinically recognized conditions due to brain stem infarct, which can nowadays be identified thanks to modern neuro-imaging techniques. We present a retrospective study of 25 cases admitted to our hospital in the past eight years, to evaluate epidemiological aspects and clinical findings and to correlate these with magnetic resonance topography.

Material And Methods: Patients diagnosed in the Neurology Section of Hospital Xeral-Calde in Lugo between January 1989 and December 1997 as having Wallenberg's syndrome.