2,110 research outputs found

    Photopolymerizable platelet lysate hydrogels for customizable 3D cell culture platforms

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    3D cell culture platforms have emerged as a setting that resembles in vivo environments replacing the traditional 2D platforms. Over the recent years, an extensive effort has been made on the development of more physiologically relevant 3D cell culture platforms. Extracellular matrix-based materials have been reported as a bioactive and biocompatible support for cell culture. For example, human plasma derivatives have been extensively used in cell culture. Despite all the promising results, in most cases these types of materials have poor mechanical properties and poor stability in vitro. Here plasma-based hydrogels with increased stability are proposed. Platelet lysates are modified by addition of methacryloyl groups (PLMA) that polymerize in controlled geometries upon UV light exposure. The hydrogels could also generate porous scaffolds after lyophilization. The results show that PLMA materials have increased mechanical properties that can be easily adjusted by changing PLMA concentration or modification degree. Cells readily adhere, proliferate, and migrate, exhibiting high viability when encapsulated in PLMA hydrogels. The innovation potential of PLMA materials is based on the fact that it is a complete xeno-free solution for human cell culture, thus an effective alternative to the current gold standards for 3D cell culture based on animal products.publishe

    CISTO TRAUMÁTICO DA MANDÍBULA- RELATO DE CASO CLÍNICO

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    O  cisto  ósseo  traumático  é  uma  lesão  não  neoplásica  que representa aproximadamente 1% de todos os cistos maxilares, acometendo as regiões de corpo e sínfise de mandíbula com maior freqüência. Sua etiologia é desconhecida,  mas  acredita-se  que  o  trauma  local  seja  fator  relacionado  ao seu  desenvolvimento. Não  há  predileção  por  sexo  e  afeta mais  jovens  abaixo de 25 anos. O diagnóstico pode ser por radiografias de rotina que apresentam lesão radiolúcida, uniradicular, de crescimento lento, tamanho variável e limites definidos.  O  tratamento  é  cirúrgico  com  curetagem  e  punção

    Coupling relationship of leaf economic and hydraulic traits of alhagi sparsifolia shap. In a hyper-arid desert ecosystem

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    In this study, Alhagi sparsifolia Shap. was used to test the hypothesis that leaf economic and hydraulic traits are coupled in plants in a hyper-arid region. Five economic traits and six hydraulic traits were examined to explore the relationship. Results showed that the stomatal density (SD) on both surfaces was coupled with maximum stomatal conductance to water vapor (gwmax) and leaf tissue density (TD). SD on adaxial surface (SDaba) was significantly positively related to vein density (VD) but negatively related to leaf thickness (LT) and stomatal length on adaxial surface (SLada). Nitrogen concentration based on mass (Nmass) was significantly negatively correlated with leaf mass per area (LMA), LT, and VD, whereas nitrogen concentration based on area (Narea) was significantly positively related to LMA and TD. Mean annual precipitation (MAP) contributed the most to the changes in LT and stomatal length (SL). Soil salt contributed the most to TD, SD, and gwmax. Soli nutrients influenced the most of LMA and VD. Mean annual temperature contributed the most to Nmass and Narea. In conclusion, the economics of leaves coupled with their hydraulic traits provides an economical and efficient strategy to adapt to the harsh environment in hyper-arid regions.Fil: Yin, Hui. University Of Chinese Academy Of Sciences; China. Xinjiang University; China. Xinjiang Institute Of Ecology And Geography Chinese Academy Of Sciences; China. Cele National Station Of Observation And Research For Desert-grassland Ecosystems; ChinaFil: Tariq, Akash. University Of Chinese Academy Of Sciences; China. Cele National Station Of Observation And Research For Desert-grassland Ecosystems; China. Xinjiang Institute Of Ecology And Geography Chinese Academy Of Sciences; ChinaFil: Zhang, Bo. University Of Chinese Academy Of Sciences; China. Cele National Station Of Observation And Research For Desert-grassland Ecosystems; China. Xinjiang Institute Of Ecology And Geography Chinese Academy Of Sciences; ChinaFil: Lv, Guanghui. Xinjiang University; ChinaFil: Zeng, Fanjiang. Cele National Station Of Observation And Research For Desert-grassland Ecosystems; China. Xinjiang Institute Of Ecology And Geography Chinese Academy Of Sciences; China. University Of Chinese Academy Of Sciences; ChinaFil: Graciano, Corina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Fisiología Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Fisiología Vegetal; ArgentinaFil: Santos, Mauro. Universidade Federal de Pernambuco; BrasilFil: Zhang, Zhihao. University Of Chinese Academy Of Sciences; China. Xinjiang Institute Of Ecology And Geography Chinese Academy Of Sciences; China. Cele National Station Of Observation And Research For Desert-grassland Ecosystems; ChinaFil: Wang, Peng. Cele National Station Of Observation And Research For Desert-grassland Ecosystems; China. Xinjiang Institute Of Ecology And Geography Chinese Academy Of Sciences; ChinaFil: Mu, Shuyong. Xinjiang Institute Of Ecology And Geography Chinese Academy Of Sciences; Chin

    Efeitos antiangiogênicos in vivo convalidam a atividade antineoplásica potencial do metiljasmonato

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    Molecular plant components have long been aimed at the angiogenesis and anti-angiogenesis pathways, and have been tested as sources for antineoplasic drugs with promising success. The present work deals with the anti-angiogenic effects of Methyl Jasmonate. Jasmonate derivatives were demonstrated to selectively damage the mitochondria of cancer cells. In vitro, 1-10 mM Methyl Jasmonate induced the cell death of the human umbilical vein endothelial cells (HUVEC) and the Murine melanoma cells (B16F10), while micromolar concentrations were ineffective. In vivo, comparable concentrations were toxic and reduced the vessel density of the Chorioallantoic Membrane of the Chicken Embryo (CAM). However, 1-10 µM concentrations produced a complex effect. There was increased capillary budding, but the new vessels were leakier and less organised than corresponding controls. It is suggested that not only direct toxicity, but also the drug effects upon angiogenesis are relevant to the antineoplasic effects of Methyl Jasmonate.Moléculas de origem vegetal são, há muito, conhecidas como substâncias ativas sobre as vias de angiogênese e antiangiogênese e foram testadas como fonte de drogas antineoplásicas com sucesso promissor. Este trabalho trata dos efeitos antiangiogênicos do Metiljasmonato, um protótipo da família dos derivados do ácido jasmônico, que danificam seletivamente a mitocôndria de células neoplásicas. In vitro, metiljasmonato 1-10 mM promoveu a morte celular de células endoteliais humanas de cordão umbilical (HUVEC) e de melanoma murino (B16F10); concentrações micromolares foram inócuas. In vivo, concentrações equivalentes foram tóxicas e reduziram a densidade de vasos em membranas corioalantoicas de embrião de galinha (CAM). Entretanto, concentrações entre 1-10 µM produziram um efeito complexo. Ocorreu aumento no brotamento capilar, mas os novos vasos apresentaram-se frágeis e menos organizados que os controles correspondentes. Sugere-se que, além da toxicidade direta contra as células tumorais, a ação do metiljasmonato sobre a angiogênese seja relevante para seu efeito antineoplásico

    Mesoscopic spin confinement during acoustically induced transport

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    Long coherence lifetimes of electron spins transported using moving potential dots are shown to result from the mesoscopic confinement of the spin vector. The confinement dimensions required for spin control are governed by the characteristic spin-orbit length of the electron spins, which must be larger than the dimensions of the dot potential. We show that the coherence lifetime of the electron spins is independent of the local carrier densities within each potential dot and that the precession frequency, which is determined by the Dresselhaus contribution to the spin-orbit coupling, can be modified by varying the sample dimensions resulting in predictable changes in the spin-orbit length and, consequently, in the spin coherence lifetime.Comment: 10 pages, 2 figure

    Genome-wide signatures of complex introgression and adaptive evolution in the big cats.

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    The great cats of the genus Panthera comprise a recent radiation whose evolutionary history is poorly understood. Their rapid diversification poses challenges to resolving their phylogeny while offering opportunities to investigate the historical dynamics of adaptive divergence. We report the sequence, de novo assembly, and annotation of the jaguar (Panthera onca) genome, a novel genome sequence for the leopard (Panthera pardus), and comparative analyses encompassing all living Panthera species. Demographic reconstructions indicated that all of these species have experienced variable episodes of population decline during the Pleistocene, ultimately leading to small effective sizes in present-day genomes. We observed pervasive genealogical discordance across Panthera genomes, caused by both incomplete lineage sorting and complex patterns of historical interspecific hybridization. We identified multiple signatures of species-specific positive selection, affecting genes involved in craniofacial and limb development, protein metabolism, hypoxia, reproduction, pigmentation, and sensory perception. There was remarkable concordance in pathways enriched in genomic segments implicated in interspecies introgression and in positive selection, suggesting that these processes were connected. We tested this hypothesis by developing exome capture probes targeting ~19,000 Panthera genes and applying them to 30 wild-caught jaguars. We found at least two genes (DOCK3 and COL4A5, both related to optic nerve development) bearing significant signatures of interspecies introgression and within-species positive selection. These findings indicate that post-speciation admixture has contributed genetic material that facilitated the adaptive evolution of big cat lineages

    Developing and Validating High-Value Patient Digital Follow-Up Services: a Pilot Study in Cardiac Surgery

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    Background: The existing digital healthcare solutions demand a service development approach that assesses needs, experience, and outcomes, to develop high-value digital healthcare services. The objective of this study was to develop a digital transformation of the patients' follow-up service after cardiac surgery, based on a remote patient monitoring service that would respond to the real context challenges. Methods: The study followed the Design Science Research methodology framework and incorporated concepts from the Lean startup method to start designing a minimal viable product (MVP) from the available resources. The service was implemented in a pilot study with 29 patients in 4 iterative develop-test-learn cycles, with the engagement of developers, researchers, clinical teams, and patients. Results: Patients reported outcomes daily for 30 days after surgery through Internet-of-Things (IoT) devices and a mobile app. The service's evaluation considered experience, feasibility, and effectiveness. It generated high satisfaction and high adherence among users, fewer readmissions, with an average of 7 ± 4.5 clinical actions per patient, primarily due to abnormal systolic blood pressure or wound-related issues. Conclusions: We propose a 6-step methodology to design and validate a high-value digital health care service based on collaborative learning, real-time development, iterative testing, and value assessment.info:eu-repo/semantics/publishedVersio

    Mechanical Properties of Atomically Thin Tungsten Dichalcogenides::WS2, WSe2, and WTe2

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    Two-dimensional (2D) tungsten disulfide (WS2_2), tungsten diselenide (WSe2_2), and tungsten ditelluride (WTe2_2) draw increasing attention due to their attractive properties deriving from the heavy tungsten and chalcogenide atoms, but their mechanical properties are still mostly unknown. Here, we determine the intrinsic and air-aged mechanical properties of mono-, bi-, and trilayer (1-3L) WS2_2, WSe2_2 and WTe2_2 using a complementary suite of experiments and theoretical calculations. High-quality 1L WS2_2 has the highest Young's modulus (302.4+-24.1 GPa) and strength (47.0+-8.6 GPa) of the entire family, overpassing those of 1L WSe2_2 (258.6+-38.3 and 38.0+-6.0 GPa, respectively) and WTe2_2 (149.1+-9.4 and 6.4+-3.3 GPa, respectively). However, the elasticity and strength of WS2_2 decrease most dramatically with increased thickness among the three materials. We interpret the phenomenon by the different tendencies for interlayer sliding in equilibrium state and under in-plane strain and out-of-plane compression conditions in the indentation process, revealed by finite element method (FEM) and density functional theory (DFT) calculations including van der Waals (vdW) interactions. We also demonstrate that the mechanical properties of the high-quality 1-3L WS2_2 and WSe2_2 are largely stable in the air for up to 20 weeks. Intriguingly, the 1-3L WSe2_2 shows increased modulus and strength values with aging in the air. This is ascribed to oxygen doping, which reinforces the structure. The present study will facilitate the design and use of 2D tungsten dichalcogenides in applications, such as strain engineering and flexible field-effect transistors (FETs)
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