Recovery of dialkylimidazolium-based ionic liquids from their mixtures with acetone or water by flash distillation

In a number of applications for which novel processes based on ionic liquids have been proposed, the recovery of the ionic liquid from its mixture with a molecular solvent is a step of critical importance for the viability of the process. In this work, feasibility and conditions for such recovery by simple flash vapourisation have been explored for the particular case of three dialkylimidazolium-based ionic liquids (namely 1-ethyl-3-methylimidazolium thiocyanate ([C2mim][SCN]), 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), and 1-butyl-3-methylimidazolium acetate ([C4mim][OAc])) and either acetone or water as representative molecular solvents of industrial relevance. The isobaric vapour-liquid equilibria of the binary systems acetone + ([C2mim][SCN] or [C4mim][OAc]) and water + ([C2mim][OAc] or [C4mim][OAc]) have been determined at three different pressures (101.32, 50.00, and 30.00 or 25.00 kPa), and the data have been suitably correlated by means of the NRTL thermodynamic model. These correlations have been used in the software Aspen Plus for the development of reliable simulations of a flash unit to perform the desired separations. The results indicate the difficulty in getting the ionic liquids recovered with high purity, even if operating the flash at a pressure as low as 5 kPa and at temperatures close to the range where the thermal stability of the ionic liquids starts to get compromisedThe authors acknowledge Xunta de Galicia for support through project ED431B 2020/021. M.K.W. is grateful to the Erasmus + programme of the European Union for the award of a mobility traineeshipS

Numerical modelling of femur fracture and experimental validation using bone simulant

[EN] Bone fracture pattern prediction is still a challenge and an active field of research. The main goal of this article is to present a combined methodology (experimental and numerical) for femur fracture onset analysis. Experimental work includes the characterization of the mechanical properties and fracture testing on a bone simulant. The numerical work focuses on the development of a model whose material properties are provided by the characterization tests. The fracture location and the early stages of the crack propagation are modelled using the extended finite element method and the model is validated by fracture tests developed in the experimental work. It is shown that the accuracy of the numerical results strongly depends on a proper bone behaviour characterization.The authors gratefully acknowledge the funding support received from the Spanish Ministry of Economy and Competitiveness and the FEDER operation program for funding the Projects DPI2013-46641-R, RTC-2015-3887-8 and the Generalitat Valenciana through the Project Prometeo/2016/007.Marco, M.; Giner Maravilla, E.; Larraínzar, R.; Caeiro, JR.; Miguélez, MH. (2017). Numerical modelling of femur fracture and experimental validation using bone simulant. Annals of Biomedical Engineering. 45(10):2395-2408. https://doi.org/10.1007/s10439-017-1877-6S23952408451

Targeting joint inflammation for osteoarthritis management through stimulus-sensitive hyaluronic acid based intra-articular hydrogels

Numerous therapeutic strategies have been developed for osteoarthritis (OA) management, including intra-articular (IA) injections. The ideal IA formulation should control cartilage degradation and restore synovial fluid viscosity. To this end, we propose to combine thermo-sensitive polymers (poloxamers) with hyaluronic acid (HA) to develop suitable beta-lapachone (βLap) loaded IA formulations. The development of IA formulations with these components entails several difficulties: low βLap solubility, unknown βLap therapeutic dose and the bonded commitment of easy administration and viscosupplementation. An optimized formulation was designed using artificial intelligence tools based on the experimental results of a wide variety of hydrogels and its therapeutic capacity was evaluated on an ex vivo OA model. The formulation presented excellent rheological properties and significantly decreased the secretion of degradative (MMP13) and pro-inflammatory (CXCL8) molecules. Therefore, the developed formulation is a promising candidate for OA treatment restoring the synovial fluid rheological properties while decreasing inflammation and cartilage degradationFinancial support was received from Interreg V-A POCTEP (0245_IBEROS_1_E) EU (FEDER). Research groups are also supported by Xunta de Galicia (Competitive Reference Groups, ED431C 2020/17-FEDER) and (Grupos de Potencial Crecimiento, IN607B 2018/19-FEDER)S

Comparison of various SYSADOA for the osteoarthritis treatment: an experimental study in rabbits

Background: Osteoarthritis is thought to be the most prevalent chronic and disabling joint disease in animals and humans and its treatment is a major orthopaedic challenge because there is no ideal drug treatment to preserve joint structure and function, as well as to ameliorate the symptomatology of the disease. The aim of the present study was to assess, using histology, histomorphometry and micro-CT, the effects of the treatment with several drugs of the SYSADOA group and a bisphosphonate in a model of early osteoarthritis, comparing all the results obtained. Methods: Osteoarthritis was surgically induced by anterior cruciate ligament transection and partial meniscectomy on one knee of 56 rabbits; treatment was started three weeks after surgery and lasted 8 weeks; at the end of this period, the animals were sacrificed. Animals were divided into seven groups (8 animals each), one for each regimen of treatment (glucosamine sulfate, chondroitin sulfate, hyaluronic acid, diacerein, risedronate and a combination of risedronate and glucosamine) and one for the control (placebo-treated) group. Following sacrifice, femoral osteochondral cylinders and synovial membrane samples were obtained for their evaluation by qualitative and quantitative histology and micro-CT. Results: The model induced osteoarthritic changes in the knee joints and none of the treatments showed a significantly better efficacy over the others. Regarding cartilage thickness and volume, all the treatments achieved scores halfway between control groups, without statistical differences. Regarding the synovial membrane, diacerein and risedronate showed the best anti-inflammatory profile, whereas glucosamine and chondroitin did not present any effect standing the hyaluronic acid results between the others. Regarding the subchondral bone, there were no differences in thickness or volume, but risedronate, diacerein and hyaluronic acid seemed to have considerably modified the orientation of the trabecular lattice. Conclusions: Out of the different drugs evaluated in the study for OA treatment, diacerein and risedronate showed, in all the parameters measured, a better profile of effectiveness; hyaluronic acid ameliorated cartilage swelling and promoted bone formation, but with a poor synovial effect; and finally, chondroitin and glucosamine sulfate prevented cartilage swelling in a similar way to the others, but had no effect on cartilage surface, synovial membrane or subchondral bone.The authors thank the Dirección Xeral de I + D + i, Consellería de Economía e Industria, Xunta de Galicia for funding this work through research project 09CSA008E, cofinanced by European regional and social funds (FEDER and FSE) from European Union and by a grant of Fundación Salud 2000S

Effects of glucosamine and risedronate alone or in combination in an experimental rabbit model of osteoarthritis

Background: The osteoarthritis (OA) treatment in humans and in animals is a major orthopaedic challenge because there is not an ideal drug for preserving the joint structure and function. The aim of this study was to assess the effects of the treatment with oral glucosamine and risedronate alone or in combination on articular cartilage, synovial membrane and subchondral bone in an experimental rabbit model of OA. Osteoarthritis was surgically induced on one knee of 32 New Zealand White rabbits using the contralateral as healthy controls. Three weeks later treatments were started and lasted 8 weeks. Animal were divided in four groups of oral treatment: the first group received only saline, the second 21.5 mg/kg/day of glucosamine sulfate, the third 0.07 mg/kg/day of risedronate; and the fourth group both drugs simultaneously at the same dosages. Following sacrifice femurs were removed and osteochondral cylinders and synovial membrane were obtained for its histological and micro-CT evaluation. Results: Sample analysis revealed that the model induced osteoarthritic changes in operated knees. OA placebo group showed a significant increase in cartilage thickness respect to the control and inflammatory changes in synovial membrane; whereas subchondral bone structure and volumetric bone mineral density remained unchanged. All the treated animals showed an improvement of the cartilage swelling independent of the drug used. Treatment with glucosamine alone seemed to have no effect in the progression of cartilage pathology while risedronate treatment had better results in superficial fibrillation and in resolving the inflammatory changes of the tissues, as well as modifying the orientation of trabecular lattice. The combination of both compounds seemed to have additive effects showing better results than those treated with only one drug. Conclusions: The results of this animal study suggested that glucosamine sulfate and risedronate treatment alone or in combination may be able to stop cartilage swelling. The risedronate treatment could partially stop the fibrillation and the inflammation of synovial membrane as well as modify the orientation of trabeculae in healthy and in osteoarthritic kneesThe authors thank the Dirección Xeral de I + D + i, Consellería de Economía e Industria, Xunta de Galicia for funding this work through research project 09CSA008E, cofinanced by European regional and social funds (FEDER and FSE) from European Union and by a grant of Fundación Salud 2000S

Analysis of mechanical behavior variation in the proximal femur using X-FEM (Extended Finite Element Method)

Introducción: El fémur humano ha sido ampliamente estudiado desde hace muchos años de manera experimental con análisis in vitro, y ahora, gracias a los avances de la informática, también se puede analizar de manera numérica. Algunos autores han demostrado la capacidad del método de los elementos finitos para predecir el comportamiento mecánico de este hueso, pero todavía son muchas las posibilidades recurriendo a la sinergia entre el método de los elementos finitos y ensayos experimentales. En este trabajo, por ejemplo, se estudia cómo afectan distintas simulaciones de osteoporosis a las cargas de fractura del fémur. El objetivo de este estudio es predecir la fractura de cadera, tanto la carga a la que se produce ésta como la propagación de la fisura sobre el hueso. Aplicando el método de los elementos finitos al campo de la biomecánica se puede realizar una simulación que muestre el comportamiento del hueso bajo diferentes condiciones de carga. Material y métodos: A partir de imágenes DICOM de tomografía computarizada de la extremidad proximal del fémur derecha de un varón se ha obtenido la geometría del hueso. Mediante un programa informático se han generado las propiedades mecánicas dependientes de la densidad mineral ósea de cada vóxel, y posteriormente se ha utilizado un código de elementos finitos para aplicar diferentes configuraciones de carga y estudiar los valores de fractura del hueso. El modelo numérico ha sido validado a través de un artículo de la literatura científica. Resultados: La carga de fractura en configuración de caída lateral es aproximadamente la mitad que la carga en el caso de la posición normal, lo cual concuerda con diferentes estudios experimentales presentes en la literatura científica. Además se han estudiado diferentes condiciones de carga en situaciones cotidianas, en las que se ha observado que la carga de fractura es mínima en la posición monopodal. También se han simulado condiciones de osteoporosis en las que se ha comprobado cómo desciende la carga de fractura al disminuir las propiedades mecánicas óseas. Conclusiones: Mediante el método de los elementos finitos en conjunto con una imagen médica DICOM es posible el estudio de la biomecánica de la cadera y obtener una estimación del fallo del hueso. Además se pueden aplicar diferentes configuraciones de carga y variar las propiedades mecánicas del hueso para simular el comportamiento mecánico de éste bajo condiciones osteoporóticas.Introduction: For years, the human femur has been extensively studied experimentally with in vitro analysis. Nowadays, with computer advances, it can also be analyzed numerically. Some authors report the usefulness of finite method in predicting the mechanical behavior of this bone. There are many possibilities using the synergy between the method finite element and experimental trials. In this paper, for example, we study how they affect different osteoporotic simulations involving femur fracture loads. The aim of this study is to predict hip fracture, both the load to which this occurs as the propagation of the crack in the bone. By applying the finite element method to the field of bio-mechanics, simulation can be carried out to show the behavior under different bone load conditions. Material and methods: Using DICOM images, CT scan of the proximal end of the right femur of a male has been obtained bone geometry. By a computer program they have been generated dependent mechanical properties of the BMD each voxel, and then used a finite code to apply different load configurations and study values bone fracture elements. The numerical model has been validated in the literature. Results: Load breaking in lateral fall configuration is approximately half the load in the case of the normal position, which agrees with different experimental studies published. In addition, we have studied various load conditions in everyday situations, where it was observed that the load fracture is minimal in mono-podal position. Osteoporotic conditions have also been simulated which confirmed that the load fracture has been reduced by decreasing mechanical properties. Conclusions: By using the finite element method in conjunction with DICOM medical imaging, it is possible to study the biomechanics of the hip and obtain an estimate of bone failure. In addition, different load configurations can be applied and vary the mechanical properties of bone to simulate the mechanical behavior of low osteoporotic conditions.S

Management of Open Fracture

Open fractures are common and their prevalence is increasing in elderly people. The burden of open fractures is high because of economic and social costs. Most open fractures occur in lower limbs. The use of validated protocols, will optimize our outcomes when treating open fractures. The first step began with the proper identification of the fracture characteristics and the hidden soft tissue injury. The use of an adequate and early antibiotic prophylaxis is mandatory and then, we have to perform adequate irrigation and debridement. Finally, we have to decide to temporally fix the fracture or proceed with the definitive fixation method. Recently, the creation of dedicated “orthoplastic” units has increased the outcomes in high-energy tibial fractures. These fractures should be managed in adequate trauma centers that should be used to face all the complications that will appear during the reconstruction procedure because complications can be as high as 50% in high-energy open fractures

Multiple vertebral fractures after suspension of denosumab. A series of 56 cases

Background: Denosumab is a monoclonal antibody approved for the treatment of postmenopausal osteoporosis. The withdrawal of denosumab produces an abrupt loss of bone mineral density and may cause multiple vertebral fractures (MVF). Objective: The objective of this study is to study the clinical, biochemical, and densitometric characteristics in a large series of postmenopausal women who suffered MVF after denosumab withdrawal. Likewise, we try to identify those factors related to the presence of a greater number of vertebral fractures (VF). Patients and methods: Fifty-six patients (54 women) who suffered MVF after receiving denosumab at least for three consecutive years and abruptly suspended it. A clinical examination was carried out. Biochemical bone remodelling markers (BBRM) and bone densitometry at the lumbar spine and proximal femur were measured. VF were diagnosed by magnetic resonance imaging MRI, X-ray, or both at dorsal and lumbar spine. Results: Fifty-six patients presented a total of 192 VF. 41 patients (73.2%) had not previously suffered VF. After discontinuation of the drug, a statistically significant increase in the BBRM was observed. In the multivariate analysis, only the time that denosumab was previously received was associated with the presence of a greater number of VF (P = .04). Conclusions: We present the series with the largest number of patients collected to date. 56 patients accumulated 192 new VF. After the suspension of denosumab and the production of MVF, there was an increase in the serum values of the BBRM. The time of denosumab use was the only parameter associated with a greater number of fractures

Extracellular Vesicles Enriched in Connexin 43 Promote a Senescent Phenotype in Bone and Synovial Cells Contributing to Osteoarthritis Progression

[Abstract] The accumulation of senescent cells is a key characteristic of aging, leading to the progression of age-related diseases such as osteoarthritis (OA). Previous data from our laboratory has demonstrated that high levels of the transmembrane protein connexin 43 (Cx43) are associated with a senescent phenotype in chondrocytes from osteoarthritic cartilage. OA has been reclassified as a musculoskeletal disease characterized by the breakdown of the articular cartilage affecting the whole joint, subchondral bone, synovium, ligaments, tendons and muscles. However, the mechanisms that contribute to the spread of pathogenic factors throughout the joint tissues are still unknown. Here, we show for the first time that small extracellular vesicles (sEVs) released by human OA-derived chondrocytes contain high levels of Cx43 and induce a senescent phenotype in targeted chondrocytes, synovial and bone cells contributing to the formation of an inflammatory and degenerative joint environment by the secretion of senescence-associated secretory associated phenotype (SASP) molecules, including IL-1ß and IL-6 and MMPs. The enrichment of Cx43 changes the protein profile and activity of the secreted sEVs. Our results indicate a dual role for sEVs containing Cx43 inducing senescence and activating cellular plasticity in target cells mediated by NF-kß and the extracellular signal-regulated kinase 1/2 (ERK1/2), inducing epithelial-to-mesenchymal transition (EMT) signalling programme and contributing to the loss of the fully differentiated phenotype. Our results demonstrated that Cx43-sEVs released by OA-derived chondrocytes spread senescence, inflammation and reprogramming factors involved in wound healing failure to neighbouring tissues, contributing to the progression of the disease among cartilage, synovium, and bone and probably from one joint to another. These results highlight the importance for future studies to consider sEVs positive for Cx43 as a new biomarker of disease progression and new target to treat OA.This work was supported in part through funding from Health Institute ‘Carlos III’ (ISCIII, Spain), the European Regional Development Fund, ‘A way of making Europe’ from the European Union (to MDM): grant PI19/00145; a grant from the Joint Transnational Call for Proposals for “European Innovative Research & Technological Development Projects in Nanomedicine” EURONANOMED III (AC21_2/00026) (to MDM); a grant from Xunta de Galicia (IN607B2020/12) (to MDM) and from H2020, Future and Emerging Technologies (grant 858014 “PANACHE”) to MDM. MV-E was funded with a predoctoral (ED481A-2015/188) and post-doctoral fellowship (IN606B-2019/004) from Xunta de Galicia. AG-C was funded with a predoctoral fellowship (FIS20/00310) from ISCIII. PC-F was funded with a post-doctoral fellowship and a grant from Xunta de Galicia (INB606B 2017/014 and IN606C 2021/006). We thank members of the CellCOM group for helpful technical suggestion, María Dolores Álvarez Alvariño (CHUS) for generously collecting tissue samples in the operating room after surgery and Arantxa Tabernero (INCYL, University of Salamanca) for kindly providing the human Cx43 plasmid used in this studyXunta de Galicia; IN607B2020/12Xunta de Galicia; ED481A-2015/188Xunta de Galicia; IN606B-2019/004Xunta de Galicia; INB606B 2017/014Xunta de Galicia; IN606C 2021/00

Senolytic Activity of Small Molecular Polyphenols from Olive Restores Chondrocyte Redifferentiation and Promotes a Pro-Regenerative Environment in Osteoarthritis

[Abstract] Articular cartilage and synovial tissue from patients with osteoarthritis (OA) show an overactivity of connexin43 (Cx43) and accumulation of senescent cells associated with disrupted tissue regeneration and disease progression. The aim of this study was to determine the effect of oleuropein on Cx43 and cellular senescence for tissue engineering and regenerative medicine strategies for OA treatment. Oleuropein regulates Cx43 promoter activity and enhances the propensity of hMSCs to differentiate into chondrocytes and bone cells, reducing adipogenesis. This small molecule reduce Cx43 levels and decrease Twist-1 activity in osteoarthritic chondrocytes (OACs), leading to redifferentiation, restoring the synthesis of cartilage ECM components (Col2A1 and proteoglycans), and reducing the inflammatory and catabolic factors mediated by NF-kB (IL-1ß, IL-6, COX-2 and MMP-3), in addition to lowering cellular senescence in OACs, synovial and bone cells. Our in vitro results demonstrate the use of olive-derived polyphenols, such as oleuropein, as potentially effective therapeutic agents to improve chondrogenesis of hMSCs, to induce chondrocyte re-differentiation in OACs and clearing out senescent cells in joint tissues in order to prevent or stop the progression of the disease.Xunta de Galicia; IN607B 2017/21Xunta de Galicia; ED481A-2015/188Xunta de Galicia; IN606B-2019/004Xunta de Galicia; IN606B-2017/014This work was supported in part through funding from the Spanish Foundation for Research on Bone and Mineral Metabolism (FEIOMM), grant PRECIPITA-2015-000139 from the FECYT-Ministry of Economy and Competitiveness (to M.D.M.), grant PI16/00035 and PI19/00145 from the Health Institute ‘Carlos III’ (ISCIII, Spain), the European Regional Development Fund, ‘A way of making Europe’ from the European Union (to M.D.M.) and a grant from Xunta de Galicia IN607B 2017/21 (to M.D.M.). M.V.-E. was funded with a predoctoral (ED481A-2015/188) and a postdoctoral fellowship (IN606B-2019/004) from Xunta de Galicia. P.C.-F. was funded with a postdoctoral fellowship (IN606B-2017/014) from Xunta de Galicia