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Implantoplasty is one of the most common techniques to remove peri-implantitis from the surface of dental implants. It is a process of mechanization of the titanium surface, causing the loss of the roughness of the dental implant, which leads to difficulty in tissue regeneration. The aim of this research is to apply a decontaminant based on citric acid and add collagen and magnesium cations to promote tissue formation and have a bactericidal character. Eighty commercially pure grade 3 titanium discs were used to perform the implantoplasty protocol, like the one used in dental clinics. They were treated with four different solutions: 25% citric acid, 25% citric acid with the addition of collagen 0.25 g/L, 25% citric acid with the addition of 0.50 g/L and the latter with the addition of 1% Mg (NO3)2. The roughness was determined by confocal microscopy, the contact angle, adhesion and proliferation of HFFs fibroblasts, proliferation of SaOS-2 osteoblasts and bactericidal behavior by culturing very common bacteria in the oral cavity, Gram-positive Streptococcus sanguinis and gordonii and as Gram-negative Pseudomonas aeruginosa. The results showed that the treatment with citric acid slightly increases the roughness and decreases the contact angle from 78 to 13°, making the surface superhydrophilic. Fibroblast proliferation studies show a very significant increase at 24 h, the most favorable solution being the one containing 0.50 g/L of collagen with the presence of magnesium in a 25% citric acid solution. This same solution shows the highest cytocompatibility and osteoblastic proliferation with statistically significant differences with respect to the control and the rest of the solutions. Microbiological studies show a bactericidal effect due to the presence of citric acid, which is especially effective on Gram-positive bacteria. The results allow us to have mouthwashes that can be applied in the patient's mouth, which will help the regeneration of tissues and avoid new bacterial colonization. [ABSTRACT FROM AUTHOR]

In contemporary urban areas, a growing 'generation rent' is finding shelter in expensive and precarious private rental housing. Tenant organisations and legislative initiatives have been pushing to improve housing conditions for renters, yet have been met with strong resistance. Intense policy and academic debates have ensued. This paper delves into the discourses used by dominant actors involved in legislative changes affecting the private rental sector in Catalonia and Spain. Through a critical discourse analysis of the positions of governments, opposition parties and landlord organisations, we identify three main arguments employed to limit or contest 'post-neoliberal' measures favouring tenants: 'the vulnerable landlord', 'the counterproductive effects' and 'the violation of property rights'. Each of these arguments is placed under theoretical and empirical scrutiny, revealing important weaknesses. By unsettling dominant discourses, we contribute to advancing the terms of the debates and sketch out the coordinates for a counter-discourse informed by critical theory and the interests of renters rather than rentiers. [ABSTRACT FROM AUTHOR]

Intrinsic fluorescence of drugs brings valuable information on their localization in the organism and their interaction with key biomolecules. In this work, we investigate the absorption and emission properties of the topical retinoid adapalene in different solvents and biological media. While the UVA/UVB absorption band does not exhibit any significant solvent-dependent behavior, a strong positive solvatochromism is observed for the emission. These results are in line with molecular modeling and simulations that show the presence of two quasi-degenerate states, i.e., a local π-π* and an intermolecular charge-transfer (ICT) state. However, molecular modeling also revealed that, whatever the solvent, at the corresponding equilibrium geometry the lowest and emissive excited state is the local π-π*. Finally, the potential of adapalene to act as a biological probe is demonstrated using albumin, DNA and micelles. [ABSTRACT FROM AUTHOR]

The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of grit blasting and subsequent acid etching (GBLAST + AE). Human amniotic mesenchymal (hAMSCs) and epithelial stem cells (hAECs) isolated from the amniotic membrane have attractive stem-cell properties. They were cultured on titanium surfaces to analyze their impact on biological behavior. The surface roughness, microhardness, wettability, and surface energy were analyzed using interferometric microscopy, Vickers indentation, and drop-sessile techniques. The GBLAST and GBLAST + AE surfaces showed higher roughness, reduced hydrophilicity, and lower surface energy with significant differences. Increased microhardness values for GBLAST and GBLAST + AE implants were attributed to surface compression. Cell viability was higher for hAMSCs, particularly on GBLAST and GBLAST + AE surfaces. Alkaline phosphatase activity enhanced in hAMSCs cultured on GBLAST and GBLAST + AE surfaces, while hAECs showed no mineralization signals. Osteogenic gene expression was upregulated in hAMSCs on GBLAST surfaces. Moreover, α2 and β1 integrin expression enhanced in hAMSCs, suggesting a surface−integrin interaction. Consequently, hAMSCs would tend toward osteoblastic differentiation on grit-blasted surfaces conducive to osseointegration, a phenomenon not observed in hAECs. [ABSTRACT FROM AUTHOR]

One of the most important challenges in endodontics is to have files that have excellent flexibility, toughness, and high fatigue life. Superelastic NiTi alloys have been a breakthrough and the new R-phase NiTi alloys promise to further optimize the good properties of NiTi alloys. In this work, two austenitic phase endodontic files with superelastic properties (Protaper and F6) and two austenitic phase files with the R-phase (M-wire and Reciproc) have been studied. The transformation temperatures were studied by calorimetry. Molds reproducing root canals at different angles (30, 45, and 70°) were obtained with cooling and loads simulating those used in the clinic. Mechanical cycles of different files were realized to fracture. Transformation temperatures were determined at different number of cycles. The different files were heat treated at 300 and 500 °C as the aging process, and the transformation temperatures were also determined. Scanning and transmission electron microscopy was used to observe the fractography and precipitates of the files. The results show that files with the R-phase have higher fracture cycles than files with only the austenitic phase. The fracture cycles depend on the angle of insertion in the root canal, with the angle of 70° being the one with the lowest fracture cycles in all cases. The R-Phase transformation increases the energy absorbed by the NiTi to produce the austenitic to R-phase and to produce the martensitic transformation causing the increase in the fracture cycles. Mechanical cycling leads to significant increases in the transformation temperatures Ms and Af as well as Rs and Rf. No changes in the transformation temperatures were observed for aging at 300 °C, but the appearance of Ni4Ti3 precipitates was observed in the aging treatments to the Nickel-rich files that correspond to those with the R transition. These results should be considered by endodontists to optimize the type of files for clinical therapy. [ABSTRACT FROM AUTHOR]

This paper examines the physical limits but paradoxically symbolic expansion of the Airbnb model beyond the the touristified historical center of Madrid. We move to the margins of the city and analyzed every host ad and guest comment in the Villaverde district, characterized as a former industrial working-class neighborhood also welcoming various waves of immigrants. Our results reveal a novel figure in the platform model, which we have characterized as the "peripheral host," who attempts to participate in this business model based on two strategies: first, by constructing an imaginary "digital tourism space" that inserts the periphery into the tourist city; and second, by "platforming host practices" through the provision of a "personalized guest experience" and on-demand tasks. In our study, we propose an explanatory model that sheds light on the ways in which platform urbanism is transforming work, culture and urban society beyond city center. [ABSTRACT FROM AUTHOR]

The rapid growth of short-term rentals (STRs) is leading researchers to frame these urban transformations indifferently as gentrification, touristification or tourism gentrification. This paper proposes that these concepts, though closely related, are not best suited to explain the urban transformations created by STRs. Using a theoretical and empirical approach, it attempts to delve into this theoretical debate. Since housing assetization is what ultimately drives the process, STRs should be framed as a specific form of housing assetization. It is suggested that the term that best captures this urban accumulation strategy and has greater explanatory power is that of STR housing assetization. The aim of this paper is twofold. Firstly, to theoretically justify the suitability of the STR housing assetization concept and specify its particularities as an urban accumulation strategy. Secondly, this accumulation strategy can be empirically observed by analyzing how STR markets develop in particular cities. For this purpose, the Spanish city of Valencia has been chosen. [ABSTRACT FROM AUTHOR]

Implantoplasty is a technique increasingly used to remove the biofilm that causes peri-implantitis on dental implants. This technique of mechanization of the titanium surface makes it possible to eliminate bacterial colonies, but it can generate variations in the properties of the implant. These variations, especially those in fatigue resistance and electrochemical corrosion behavior, have not been studied much. In this work, fatigue tests were performed on 60 dental implants without implantoplasty, namely 30 in air and 30 in Hank's solution at 37 °C, and 60 with implatoplasty, namely 30 in air and 30 in Hank's solution at 37 °C, using triaxial tension–compression and torsion stresses simulating human chewing. Mechanical tests were performed with a Bionix servo-hydraulic testing machine and fracture surfaces were studied by scanning electron microcopyElectrochemical corrosion tests were performed on 20 dental implants to determine the corrosion potentials and corrosion intensity for control implants and implantoplasty implants. Studies of titanium ion release to the physiological medium were carried out for each type of dental implants by Inductively Coupled-Plasma Mass Spectrometry at different immersion times at 37 °C. The results show a loss of fatigue caused by the implantoplasty of 30%, observing that the nucleation points of the cracks are in the areas of high deformation in the areas of the implant neck where the mechanization produced in the treatment of the implantoplasty causes an exaltation of fatigue cracks. It has been observed that tests performed in Hank's solution reduce the fatigue life due to the incorporation of hydrogen in the titanium causing the formation of hydrides that embrittle the dental implant. Likewise, the implantoplasty causes a reduction of the corrosion resistance with some pitting on the machined surface. Ion release analyses are slightly higher in the implantoplasted samples but do not show statistically significant differences. It has been observed that the physiological environment reduces the fatigue life of the implants due to the penetration of hydrogen into the titanium forming titanium hydrides which embrittle the implant. These results should be taken into account by clinicians to determine the convenience of performing a treatment such as implantoplasty that reduces the mechanical behavior and increases the chemical degradation of the titanium dental implant. [ABSTRACT FROM AUTHOR]

C-REPEAT BINDING FACTORS (CBFs) are highly conserved plant transcription factors that promote cold tolerance. In Arabidopsis (Arabidopsis thaliana), three CBFs (CBF1 to CBF3) play a critical role in cold acclimation, and the expression of their corresponding genes is rapidly and transiently induced during this adaptive response. Cold induction of CBFs has been extensively studied and shown to be tightly controlled, yet the molecular mechanisms that restrict the expression of each CBF after their induction during cold acclimation are poorly understood. Here, we present genetic and molecular evidence that the decline in the induction of CBF3 during cold acclimation is epigenetically regulated through the Polycomb Repressive Complex (PRC) 2. We show that this complex promotes the deposition of the repressive mark H3K27me3 at the coding region of CBF3, silencing its expression. Our results indicate that the cold-inducible long noncoding RNA SVALKA is essential for this regulation by recruiting PRC2 to CBF3. These findings unveil a SVALKA-PRC2 regulatory module that ensures the precise timing of CBF3 induction during cold acclimation and the correct development of this adaptive response. [ABSTRACT FROM AUTHOR]

Lithium nickel oxide, LiNiO2, has attracted considerable interest as a high energy cathode for next generation lithium-ion batteries. Nevertheless, shortcomings such as significant cycling capacity decay and low stability in ambient atmosphere have hindered its practical application, and consequently most work has focused on the more stable Mn and Co doped analogues Li(Ni,Mn,Co)O2. Here, we report an investigation of an alternative strategy, sulfate modification, in the LiNiO2 system. We show that improved performance can be achieved, attributed to the dual effect of a low level of bulk doping and the presence of a self-passivation Li2SO4 layer formed beyond the solid solution limit. Ab initio simulations suggest that the behavior is similar to that of other high valent dopants such as W and Mo. These dual effects contribute to the improved air stability and enhanced electrochemical performance for the sulfate modified lithium-rich LiNiO2, leading to high initial capacities (∼245 mA h g−1 at 25 mA g−1, and ∼205 mA h g−1 at 100 mA g−1) and better capacity retention. Overall, the results show that polyanion modification represents an excellent alternative low-cost strategy to improve the performance of lithium nickel oxide cathode materials. [ABSTRACT FROM AUTHOR]

This article discusses the case of a 46-year-old woman with sclerotic bone lesions (SBL) who was diagnosed with tuberous sclerosis complex (TSC). TSC is a genetic disorder characterized by benign hamartomas in various organs, including the brain, skin, eye, heart, kidney, and lung. While SBL is not included as a diagnostic criterion for TSC, studies have reported a high prevalence of SBL in patients with TSC. It is important to be aware of SBL in TSC to avoid misdiagnosis with osteoblastic metastases, especially in adults. [Extracted from the article]

Advance care planning is a deliberative process that aims to help patients define goals and preferences for future care and treatment at a times when they have limited decision-making capacity. This study aims to analyze models of advance care planning in elderly individuals living in nursing homes. We reviewed papers published in Cochrane, PubMed and Embase. A total of 26 studies were selected, including a total of 44,131 people over 65 years of age. We analyzed the types of intervention (interviews, videos, workshops, documentation, etc.) and their results derived from the application. We conclude that no study implements a standardized intervention model. These interventions include decision-making (transfers to hospital, resucitation orders) and the adequacy of therapeutic effort (antibiotherapy, nutrition, serotherapy, etc.). Other outcomes are implementation barriers (time and training)., (Copyright © 2024 SEGG. Publicado por Elsevier España, S.L.U. All rights reserved.)