Biostable Scaffolds of Polyacrylate Polymers Implanted in the Articular Cartilage Induce Hyaline-Like Cartilage Regeneration in Rabbits

2017

[EN] Purpose: To study the influence of scaffold properties on the organization of ¿in vivo¿ cartilage regeneration. Our hypothesis is that stress transmission to the cells seeded inside the scaffold pores or surrounding it, which is highly dependent on the scaffold properties, determine differentiation of both mesenchymal cells and dedifferentiated autologous chondrocytes. Methods: Four series of porous scaffolds made of different polyacrylate polymers, previously seeded with cultured rabbit chondrocytes or without cells preseeded, were implanted in cartilage defects in rabbits. Subchondral bone was always injured during the surgery in order to allow blood to reach the implantation site an…

Electrothermal Atomic Absorption Spectrometric Diagnosis of Familial Hypercholesterolemia

2000

We have developed a new nonradioactive assay to identify human low-density lipoprotein receptor defects. It is based on the incubation of cultured cells with colloidal gold-LDL conjugates and quantitation of the gold associated with the cells by electrothermal atomic absorption spectrometry. After an oxidative treatment with nitric and hydrochloric acids, the biological matrix interferes neither with the gold recovery nor with the gold measurements, which are linear, at least from 0.15 to 3 ng of gold. When cells expressing a functional LDL receptor are incubated with increasing amounts of colloidal-gold LDL conjugates, the obtained saturation curve parallels that described when [125I]LDL i…

Gradual complement protein adsorption and macrophage polarization: inflammation & dental implants

2020

Alginate-Agarose Hydrogels Improve the In Vitro Differentiation of Human Dental Pulp Stem Cells in Chondrocytes. A Histological Study

2021

[EN] Matrix-assisted autologous chondrocyte implantation (MACI) has shown promising results for cartilage repair, combining cultured chondrocytes and hydrogels, including alginate. The ability of chondrocytes for MACI is limited by different factors including donor site morbidity, dedifferentiation, limited lifespan or poor proliferation in vitro. Mesenchymal stem cells could represent an alternative for cartilage regeneration. In this study, we propose a MACI scaffold consisting of a mixed alginate-agarose hydrogel in combination with human dental pulp stem cells (hDPSCs), suitable for cartilage regeneration. Scaffolds were characterized according to their rheological properties, and their…

Histological study of human periodontal tissue following biologically oriented preparation technique (BOPT)

2020

Background The aim of this study was to conduct histological analysis of a human tooth resected with the periodontal insertion apparatus intact following treatment using biologically oriented preparation technique (BOPT). Material and methods This descriptive histological dento-periodontal study used an anterior tooth extracted with the surrounding periodontal tissues intact, following prosthetic restoration with BOPT. The sample patient was recruited from among those attending the Department of Dental Medicine at the Faculty of Medicine and Dentistry, University of Valencia (Spain). Eight serial sections of the restored tooth were processed. The relative location and histological character…

Design and experimental validation of a magnetic device for stem cell culture.

2020

Cell culture of bone and tendon tissues requires mechanical stimulation of the cells in order to mimic their physiological state. In the present work, a device has been conceived and developed to generate a controlled magnetic field with a homogeneous gradient in the working space. The design requirement was to maximize the magnetic flux gradient, assuring a minimum magnetizing value in a 15 mm × 15 mm working area, which highly increases the normal operating range of this sort of devices. The objective is to use the machine for two types of biological tests: magnetic irradiation of biological samples and force generation on paramagnetic particles embedded in scaffolds for cell culture. The…

Identificación y caracterización del primer español con defecto homocigoto familiar de unión de la apolipoproteína B

2001

Fundamento El defecto familiar de union de la apolipoproteina B-100 (DFB) es una enfermedad hereditaria autosomica dominante debida a mutaciones localizadas en el gen de la apolipoproteina B-100, clinicamente indistinguible de la hipercolesterolemia familiar. Describimos el primer homocigoto espanol para el DFB. Metodos Estudiamos por tecnica de PCR–SSCP la mutacion R3500Q en los familiares de primer y segundo grado de la familia con DFB previamente descrita por nuestro grupo. Ademas, analizamos la actividad del receptor de LDL en un ensayo con LDL conjugada con oro coloidal. Resultados El paciente presenta en ambos alelos la mutacion R3500Q causante de DFB. El estudio de la actividad del r…

Cannabinoid receptor expression in non-small cell lung cancer. Effectiveness of tetrahydrocannabinol and cannabidiol inhibiting cell proliferation an…

2020

Background/Objective Patients with non-small cell lung cancer (NSCLC) develop resistance to antitumor agents by mechanisms that involve the epithelial-to-mesenchymal transition (EMT). This necessitates the development of new complementary drugs, e.g., cannabinoid receptors (CB1 and CB2) agonists including tetrahydrocannabinol (THC) and cannabidiol (CBD). The combined use of THC and CBD confers greater benefits, as CBD enhances the effects of THC and reduces its psychotropic activity. We assessed the relationship between the expression levels of CB1 and CB2 to the clinical features of a cohort of patients with NSCLC, and the effect of THC and CBD (individually and in combination) on prolifer…

In Vivo Articular Cartilage Regeneration Using Human Dental Pulp Stem Cells Cultured in an Alginate Scaffold: A Preliminary Study

2017

Osteoarthritis is an inflammatory disease in which all joint-related elements, articular cartilage in particular, are affected. The poor regeneration capacity of this tissue together with the lack of pharmacological treatment has led to the development of regenerative medicine methodologies including microfracture and autologous chondrocyte implantation (ACI). The effectiveness of ACI has been shown in vitro and in vivo, but the use of other cell types, including bone marrow and adipose-derived mesenchymal stem cells, is necessary because of the poor proliferation rate of isolated articular chondrocytes. In this investigation, we assessed the chondrogenic ability of human dental pulp stem c…

Cartilage Regeneration and Tissue Engineering

2019

Abstract Articular cartilage in synovial joints is a hyaline cartilage highly hydrated with a rigorous order of cells and fibers and a specific content of proteoglycans and glycoproteins. It provides a low-friction surface, participates in the lubrication of the synovial joints, and distributes the forces to the underlying bone. It is an avascular and aneural tissue where small metabolites diffuse to and from cells. Unlike hyaline cartilage in other locations, articular cartilage lacks perichondrium, a layer of fibrous tissue around it that serves as the source of new cartilage cells. Thus, although extracellular matrix undergoes continuous remodeling throughout life, the ability to repair …

Influence of the Use of a Collagen Membrane Placed on the Bone Window after Sinus Floor Augmentation—An Experimental Study in Rabbits

2021

Background: We studied the influence on healing of a resorbable membrane covering the osteotomy site after maxillary sinus grafting, evaluated in different regions of the augmented area. Methods: Maxillary sinus augmentation was performed in 24 New Zealand rabbits. Osteotomy, 4 × 6 mm, were performed bilaterally. A collagenated cortico-cancellous porcine bone was used to fill the elevated region. A collagen membrane was randomly placed over the osteotomy site on one side (MG), and the other side was left uncovered (NMG). The animals were euthanized after 2, 4, and 8 weeks

Procedure to consistently obtain endothelial and smooth muscle cell cultures from umbilical cord vessels

2006

The prenatal history of an individual can be responsible to some extent for the occurrence of several diseases later in life. Thus, low birth weight has been related to an increased risk of developing hypertension or type 2 diabetes. The molecular and cellular basis of this increased risk could be found in body fluids and cell types that can be obtained just after birth. To get this unique information, a methodology was developed to consistently obtain cultures of 4 cell types, endothelial and smooth muscle cells from both the vein and the arteries present in the umbilical cord of an individual. From 21 umbilical cords processed, 82 of the 84 possible cell cultures were obtained. The cell c…

Influence of the use of autogenous bone particles to close the access window after maxillary sinus floor augmentation: an experimental study in rabbi…

2020

Abstract Aim To study the influence on the healing of the placement of particulate autogenous bone in the antrostomy and in the subjacent region after maxillary sinus elevation. Material and methods Sixteen New Zealand rabbits were undergone to bilateral maxillary sinus floor augmentation with 4 × 4 mm antrostomy dimension. The sinus mucosa was elevated, and the space obtained was filled with xenograft. In the test site (treated sites), autogenous bone was harvested from the tibia and was placed either in the antrostomy and the subjacent region while the control site was left untreated. Antrostomy was covered bilaterally with collagen membranes. Animals were euthanized after 1 and 8 weeks o…