Wear of hip prostheses increases serum IGFBP-1 levels in patients with aseptic loosening

The biological mechanisms involved in aseptic loosening include inflammation-associated and bone resorption-associated processes. Coordinated cellular actions result in biochemical imbalances with devastating consequences for the joint. Given that this condition is not known for showing systemic signs, we investigated whether circulating levels of inflammation-related proteins are altered in patients with aseptic loosening. Our study included 37 patients who underwent revision surgery due to hip osteolysis and aseptic loosening and 31 patients who underwent primary total hip arthroplasty. Using antibody arrays, we evaluated the serum levels of 320 proteins in four patients from each group. The results showed differences in insulin-like growth factor-binding protein 1 (IGFBP-1) concentrations, which we then quantified using enzyme-linked immunosorbent assay tests in all study patients. The results confirmed that serum IGFBP-1 concentrations were higher in the revision surgery patients than in the hip arthroplasty patients. In vitro studies showed that exposure of human osteoblasts to titanium particles induced an IGFBP-1 release that further increased when exposure to particles was performed in media conditioned by human M1 macrophages. These findings suggest that elevated serum IGFBP-1 levels in patients with aseptic loosening can arise from increased local IGFBP-1 production in the inflammatory environment of the periprosthetic bed.This work was supported by Grant RTI2018-095159-B-I00 from the Spanish Ministry of Science, Innovation and Universities (MCINN) and Grant PI18/00643 from Instituto de Salud Carlos III (ISCIII)-Fondo Europeo de Desarrollo Regional (FEDER) and the Spanish Ministry of Economy and Competitiveness (MINECO-AES). LS is supported by a Miguel Servet contract from ISCIII-MINECO-AES-FEDER-FSE. NV is supported by Program I2 from the Regional Government of Madrid. The authors are indebted to Fatima Bensiamar (IdiPAZ and CIBER-BBN) for her excellent technical assistance with the cell culture experiments and gene expression analysis and to the Cell Culture Core Facilities of IdiPAZ

Reconstruction of the rotation center of the hip after oblong cups in revision total hip arthroplasty

Background The preoperative bone defect and the reconstruction of the center of rotation of the hip are critical in acetabular revision surgery. Uncemented oblong cups are employed in order to manage these issues. We analyzed the clinical results and rates of revision of two different uncemented oblong cups, the reconstruction of the center of rotation of the hip, as well as the rate of radiological loosening and possible risk factors. Materials and methods Forty-five patients (46 hips) underwent acetabular revision surgery using two different uncemented oblong cups.Weassessed the clinical results and the survival rate for revision and aseptic loosening. Intraoperative bone loss was classified according to Paprosky, and acetabular reconstruction was assessed according to Ranawat. The mean follow-up was 7.2 years (range 4–11 years). Results There were four re-revisions (three due to aseptic loosening); the survival rate for re-revision due to aseptic loosening was 60.1 % at seven years. The mean distance between the center of the femoral head prosthesis and the approximate center of the femoral head improved from 21.5 to 10.2 mm. Thirteen cups showed radiological loosening; the survival rate for radiological loosening at seven years was 40.54 %. A smaller postoperative horizontal distance was correlated with cup loosening. Conclusions Although optimal acetabular reconstruction can be achieved by using oblong uncemented cups in revision hip surgery, the clinical and radiological results are not encouraging. Excessive medialization of the cup may increase the rate of loosenin

Procedimiento para la preparación de titanosilicatos mesoporosos tipo MCM-48, y su uso como catalizadores en reacciones de oxidación selectiva

Referencia OEPM: P9900214.-- Fecha de solicitud: 29/01/1999.-- Titulares: Universidad Politécnica de Valencia (UPV), Consejo Superior de Investigaciones Científicas (CSIC).Procedimiento para la preparación de titanosilicatos mesoporosos tipo MCM-48, que pueden presentar o no grupos orgánicos anclados en su superficie. La incorporación de titanio puede realizarse mediante síntesis directa, en la que un precursor de titanio es adicionado al gel de síntesis, o bien mediante anclaje de compuestos de titanio sobre una superficie de sílice. Estos compuestos son empleados como catalizadores en procesos de oxidación selectiva de compuestos orgánicos con peróxidos orgánicos o inorgánicos.Peer reviewe

Negociación sindicato - empresa : las ganancias de la cooperación

El papel de los sindicatos y su contribución al comportamiento de las economías, sugiere que existen beneficios cuando hay un mayor nivel de sindicalización y que el proceso de negociación de los sindicatos con las empresas en el mercado laboral podría ser más eficiente, si las partes involucradas cooperaran entre sí, con lo cual se lograría impactar positivamente el mercado laboral y los resultados de las empresas y de la economía en general. Con base en lo anterior, en este trabajo se propone un modelo que, utilizando herramientas de la teoría de juegos, permite establecer los efectos de la cooperación entre dos agentes económicos (Empresa y Sindicato), que tradicionalmente negocian de forma no cooperativa.718/5000 The role of unions and their contribution to the behavior of economies suggests that there are benefits when there is a higher level of unionization and that the negotiation process of unions with companies in the labor market could be more efficient, if the parties involved they will cooperate with each other, with which it will be possible to positively impact the labor market and the results of the companies and the economy in general. Based on the above, this paper proposes a model that, using tools of game theory, allows to establish the effects of cooperation between two economic agents (Company and Trade Union), which traditionally negotiate in a non-cooperative manner.Magíster en EconomíaMaestrí

Influence of inflammatory conditions provided by macrophages on osteogenic ability of mesenchymal stem cells

The mechanisms by which macrophage phenotype contributes to mesenchymal stem cells (MSC)- mediated bone repair remain unclear. In this work, we investigated the influence of factors released by human macrophages polarized to a pro-inflammatory or an anti-inflammatory phenotype on the ability of human MSC to attach, migrate, and differentiate toward the osteoblastic lineage. We focused on the role of TNF-α and IL-10, key pro-inflammatory and anti-inflammatory cytokines, respectively, in regulating MSC functions. Methods: MSC were treated with media conditioned by pro-inflammatory or anti-inflammatory macrophages to study their influence in cell attachment, migration, and osteogenic differentiation. The involvement of TNF-α and IL10 in the regulation of MSC functions was investigated using neutralizing antibodies and recombinant cytokines. Results: Treatment of MSC with media conditioned by pro-inflammatory or anti-inflammatory macrophages promoted cell elongation and enhanced MSC ability to attach and migrate. These effects were more noticeable when MSC were treated with media from pro-inflammatory macrophages. Interestingly, MSC osteogenic activity was enhanced by factors released by anti-inflammatory macrophages, but not by pro-inflammatory macrophages. Significant IL-10 levels originated from anti-inflammatory macrophages enhanced MSC osteogenesis by increasing ALP activity and mineralization in MSC layers cultured under osteogenic conditions. Moreover, macrophage-derived IL-10 regulated the expression of the osteogenic markers RUNX2, COL1A1, and ALPL. Notably, low TNF-α levels secreted by anti-inflammatory macrophages increased ALP activity in differentiating MSC whereas high TNF-α levels produced by pro-inflammatory macrophages had no effects on osteogenesis. Experiments in which MSC were treated with cytokines revealed that IL-10 was more effective in promoting matrix maturation and mineralization than TNF-α. Conclusions: Factors secreted by pro-inflammatory macrophages substantially increased MSC attachment and migration whereas those released by anti-inflammatory macrophages enhanced MSC osteogenic activity as well as cell migration. IL-10 was identified as an important cytokine secreted by anti-inflammatory macrophages that potentiates MSC osteogenesis. Our findings provide novel insights into how environments provided by macrophages regulate MSC osteogenesis, which may be helpful to develop strategies to enhance bone regenerationThis work was supported by grants PI15/00752 and PI15/01118 from Instituto de Salud Carlos III (ISCIII)-Fondo Europeo de Desarrollo Regional (FEDER)- Ministerio de Economía y Competitividad (MINECO)-AES, grant PI18/00643 from ISCIII-FEDER, Ministerio de Ciencia, Innovación y Universidades (MICINN)-AES and grant RTI2018-095159-B-I00 from MICINN. L.M.P is supported by a predoctoral contract (PEJD-2018-PRE/BMD-7965) from the Comunidad de Madrid (CAM

Early efficacy evaluation of mesenchymal stromal cells (MSC) combined to biomaterials to treat long bone non-unions

Artículo con numerosos autores, sólo se recogen el primero y los pertenecientes a la UAMBackground and study aim: Advanced therapy medicinal products (ATMP) frequently lack of clinical data on efficacy to substantiate a future clinical use. This study aims to evaluate the efficacy to heal long bone delayed unions and non-unions, as secondary objective of the EudraCT 2011-005441-13 clinical trial, through clinical and radiological bone consolidation at 3, 6 and 12 months of follow-up, with subgroup analysis of affected bone, gender, tobacco use, and time since the original fracture. Patients and methods: Twenty-eight patients were recruited and surgically treated with autologous bone marrow derived mesenchymal stromal cells expanded under Good Manufacturing Practices, combined to bioceramics in the surgical room before implantation. Mean age was 39 ±13 years, 57% were males, and mean Body Mass Index 27 ±7. Thirteen (46%) were active smokers. There were 11 femoral, 4 humeral, and 13 tibial non-unions. Initial fracture occurred at a mean ±SD of 27.9 ±31.2 months before recruit- ment. Efficacy results were expressed by clinical consolidation (no or mild pain if values under 30 in VAS scale), and by radiological consolidation with a REBORNE score over 11/16 points (value of or above 0.6875). Means were statistically compared and mixed models for repeated measurements estimated the mean and confidence intervals (95%) of the REBORNE Bone Healing scale. Clinical and radiological con- solidation were analyzed in the subgroups with Spearman correlation tests (adjusted by Bonferroni). Results: Clinical consolidation was earlier confirmed, while radiological consolidation at 3 months was 25.0% (7/28 cases), at 6 months 67.8% (19/28 cases), and at 12 months, 92.8% (26/28 cases including the drop-out extrapolation of two failures). Bone biopsies confirmed bone formation surrounding the bioce- ramic granules. All locations showed similar consolidation, although this was delayed in tibial non-unions. No significant gender difference was found in 12-month consolidation (95% confidence). Higher consoli- dation scale values were seen in non-smoking patients at 6 ( p = 0.012, t -test) and 12 months ( p = 0.011, t -test). Longer time elapsed after the initial fracture did not preclude the occurrence of consolidation. Conclusion: Bone consolidation was efficaciously obtained with the studied expanded hBM-MSCs com- bined to biomaterials, by clinical and radiological evaluation, and confirmed by bone biopsies, with lower consolidation scores in smokersThis research received funding from the European Union’s Sev- enth Framework Programme ( FP7/FP7-HEALTH-2009 ) with the RE- BORNE Project (under G.A. 241876), and the European Union’s Horizon 2020 Programme ( H2020-SC1 2016-2017 ), with the OR- THOUNION Project (under G.A. 7333288

Medium-term response of breeding Blue Chaffinch Fringilla teydea teydea to experimental thinning in a Pinus canariensis plantation (Tenerife, Canary Islands)

We studied the medium-term response of the endemic Blue Chaffinch Fringilla teydea teydea to experimental thinning in a Pinus canariensis plantation on the island of Tenerife during breeding season. Distance Sampling method was applied to line transects, and habitat preferences were modelled by means of univariate regression trees. The density was 1.70 birds/ha (1.09 to 2.68 95%CI) in thinned areas and 0.56 birds/ha (0.33 to 0.97 95%CI) in unthinned areas. The Blue Chaffinch densities peaked in thinned areas where the density of trees with Diameter at Breast Height of <25 cmwas between 10.5 and 16.5 trees/plot (r = 25 m) and the cover of Adenocarpus shrubs was 82.5%. Thinning had added heterogeneity into the stand structure at least in terms of lowering the basal area of small pine trees and increasing the understorey cover of Adenocarpus shrubs, with average cover being 37.15% in thinned and only 1.40% in unthinned areas.Our results justify the silvicultural thinning of 2844 hectares of pine plantation on the summit of Gran Canaria as a means of increasing the density of the endangered Gran Canaria Blue Chaffinch (Fringilla teydea polatzeki)

Negative-sequence voltage elimination for distributed generators in grid-feeding operation mode

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.A major concern of the power quality in distributed systems is related to the mitigation of voltage imbalances. This function can be implemented directly in the control system of the distributed generation power converters working simultaneously with the standard operation modes. This study presents a negative-sequence voltage elimination technique for distributed generators in grid-feeding operation mode. The proposal guarantees a complete elimination of the negativesequence voltage, while operating without a priori in-depth knowledge of the grid configuration and its characteristics. The proposed control architecture is presented together with its pseudocode, a controller flowchart and a discussion of the implementation aspects. A closed-loop modelling is derived based on a complex transfer function approach, which is used to determine stability margins and control design guidelines. A laboratory setup was implemented to verify the performance of the proposed strategy.This work was supported by the Ministry of Science, Innovation and Universities of Spain and by the European Regional Development Fund under project RTI2018-100732-B-C22.Peer ReviewedPostprint (author's final draft

Evaluation of the silver species nature in Ag-ITQ2 zeolites by the CO oxidation reaction

The authors thank the Spanish Ministry of Economy and Competitiveness through RTI2018-101784-B-I00 (MINECO/FEDER) and SEV-2016-0683 projects for the financial support. We gratefully acknowledge ALBA synchrotron for allocating beamtime (proposal 2015091414) and the CLAESS beamline staff for their help and technical support during our experiment. CG and NB thank the TUW Innovative Project GIP165CDGC. CG, SP, VT, NB and GR are thankful for financial support from the Austrian Science Fund (FWF) through projects DK+ Solids4Fun (W1243) and ComCat (I 1041-N28). I. Lopez Hernandez is grateful to Generalitat Valenciana and European Social Fund for the pre doctoral grant ACIF2017.López-Hernández, I.; García Yago, CI.; Truttmann, V.; Pollit, S.; Barrabés, N.; Rupprechter, G.; Rey Garcia, F.... (2020). Evaluation of the silver species nature in Ag-ITQ2 zeolites by the CO oxidation reaction. 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Local variability of serotinous cones in a Canary Island pine (Pinus canariensis) stand

The endemic Canary Island pine (Pinus canariensis) has an effective strategy to counteract fire disturbance in the short term. It has a mixed strategy that combines the presence of serotinous cones and thick barks with the ability to re-sprout from the trunk after a fire, a rare trait in pine species. High frequency of fires in the Canary Islands is related to human action, as natural fires by lightning or vulcan activity have very low frequency; hence, the how and whys of the presence of serotinous cones in the species is still a topic of debate. Previous studies showed that the frequency of serotinous cones varies from stand to stand. Here, we analyzed the presence of serotinous cones at a local scale. We selected a Canary Island pine stand in the transition zone between dry and humid forests in the south of Tenerife. Branches were pruned from 20 trees in order to evaluate the presence of serotinous vs. non-serotinous cones by direct verticile counting on the branches. The opening temperature of serotinous cones was assessed in the laboratory. Percentages of serotinous vs. non-serotinous cones varied from 0 to 93 %, showing high variability between trees. Opening temperatures were very high (above 65 ºC) as compared to other Mediterranean pine species with serotinous cone