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In view of the increased levels of reactive oxygen species (ROS) that disturb the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), the repair of diabetic bone defects remains a great challenge. Herein, a factor-free hydrogel is reported with ROS scavenging and responsive degradation properties for enhanced diabetic bone healing. These hydrogels contain ROS-cleavable thioketal (TK) linkers and ultraviolet (UV)-responsive norbornene (NB) groups conjugated with 8-arm PEG macromers, which are formed via UV crosslinking-mediated gelation. Upon reacting with high levels of ROS in the bone defect microenvironment, ROS-cleavable TK linkers are destroyed, allowing the responsive degradation of hydrogels, which promotes the migration of BMSCs. Moreover, ROS levels are reduced through hydrogel-mediated ROS scavenging to reverse BMSC differentiation from adipogenic to osteogenic phenotype. As such, a favorable microenvironment is created after simultaneous ROS scavenging and hydrogel degradation, leading to the effective repair of bone defects in diabetic mouse models, even without the addition of growth factors. Thus, this study presents a responsive hydrogel platform that regulates ROS scavenging and stromal degradation in bone engineering.
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Diferenciación Celular , Hidrogeles , Células Madre Mesenquimatosas , Osteogénesis , Especies Reactivas de Oxígeno , Animales , Especies Reactivas de Oxígeno/metabolismo , Hidrogeles/química , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Ratones , Diferenciación Celular/efectos de los fármacos , Diabetes Mellitus Experimental , Depuradores de Radicales Libres/farmacología , Depuradores de Radicales Libres/química , Cicatrización de Heridas/efectos de los fármacos , Huesos , MasculinoRESUMEN
The repair of irregular bone tissue suffers severe clinical problems due to the scarcity of an appropriate therapeutic carrier that can match dynamic and complex bone damage. Fortunately, stimuli-responsive in situ hydrogel systems that are triggered by a special microenvironment could be an ideal method of regenerating bone tissue because of the injectability, in situ gelatin, and spatiotemporally tunable drug release. Herein, we introduce the two main stimulus-response approaches, exogenous and endogenous, to forming in situ hydrogels in bone tissue engineering. First, we summarize specific and distinct responses to an extensive range of external stimuli (e.g., ultraviolet, near-infrared, ultrasound, etc.) to form in situ hydrogels created from biocompatible materials modified by various functional groups or hybrid functional nanoparticles. Furthermore, "smart" hydrogels, which respond to endogenous physiological or environmental stimuli (e.g., temperature, pH, enzyme, etc.), can achieve in situ gelation by one injection in vivo without additional intervention. Moreover, the mild chemistry response-mediated in situ hydrogel systems also offer fascinating prospects in bone tissue engineering, such as a Diels-Alder, Michael addition, thiol-Michael addition, and Schiff reactions, etc. The recent developments and challenges of various smart in situ hydrogels and their application to drug administration and bone tissue engineering are discussed in this review. It is anticipated that advanced strategies and innovative ideas of in situ hydrogels will be exploited in the clinical field and increase the quality of life for patients with bone damage.
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Objective: In the domain of competitive events, Latin dance athletes have always suffered competitive anxiety, which is a prevalent and prevailing psychological facet, in pre-, intra-, and post-competitive engagements. Usually, the implementation of systematic desensitization training is an efficacious approach to reduce competitive anxiety levels in routine sports to fortify psychological resilience of athletes (like swimming, volleyball, and basketball). This study focuses on the effect of systematic desensitization training on competition anxiety in the training of Latin dancers to establish good mental ability and promote the competitive ability of athletes. Methodology: The "Sports Competition Anxiety Test Questionnaire" was used to evaluate and classify the competitive anxiety levels of 150 Latin dance athletes. Then, the top 48 participants were selected (24 in the intervention cohort and 24 in the non-intervention cohort) as the study participants after stratifying anxiety score levels from the highest to the lowest. The intervention group was treated with an 8-week psychological intervention by employing systematic desensitization training techniques (encompassing imagery desensitization and in vivo desensitization). The anxiety levels of the subjects were quantified by employing the "Sport Competition Trait Anxiety Inventory" (CCTAI-C) and the "Competitive State Anxiety Inventory" (CSAI-2) to scrutinize the efficacy of systematic desensitization training in regulating competitive anxiety levels among Latin dance athletes. Results: After applying systematic desensitization training, the intervention group displayed a notable reduction in sport cognitive trait anxiety. Specifically, there was a decrease of 29.37% in social evaluation anxiety, 20.31% in competition preparation anxiety, 16.98% in performance anxiety, 25.16% in failure anxiety, 34.47% in opponent's ability anxiety, and 25.16% in injury anxiety. Moreover, for competitive state anxiety, cognitive state anxiety and somatic state anxiety decreased by 39.19 and 21.43%. The state self-confidence increased by 14.42%. Conclusion: The result indicated that systematic desensitization training not only mitigates anxiety but also positively intervenes in sports-related anxiety. Moreover, systematic desensitization training can significantly diminish competitive anxiety among Latin dance athletes to bolster confidence during competitions. Integrating desensitization training into the regular regimen of Latin dance practice has the potential to fortify dancers' psychological resilience against anxiety.
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Self-supervised depth estimation methods can achieve competitive performance using only unlabeled monocular videos, but they suffer from the uncertainty of jointly learning depth and pose without any ground truths of both tasks. Supervised framework provides robust and superior performance but is limited by the scope of the labeled data. In this paper, we introduce SENSE, a novel learning paradigm for self-supervised monocular depth estimation that progressively evolves the prediction result using supervised learning, but without requiring labeled data. The key contribution of our approach stems from the novel use of the pseudo labels - the noisy depth estimation from the self-supervised methods. We surprisingly find that a fully supervised depth estimation network trained using the pseudo labels can produce even better results than its "ground truth". To push the envelope further, we then evolve the self-supervised backbone by replacing its depth estimation branch with that fully supervised network. Based on this idea, we devise a comprehensive training pipeline that alternatively enhances the two key branches (depth and pose estimation) of the self-supervised backbone network. Our proposed approach can effectively ease the difficulty of multi-task training in self-supervised depth estimation. Experimental results have shown that our proposed approach achieves state-of-the-art results on the KITTI dataset.
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CAR-T cell therapy, a novel immunotherapy, has made significant breakthroughs in clinical practice, particularly in treating B-cell-associated leukemia and lymphoma. However, it still faces challenges such as poor persistence, limited proliferation capacity, high manufacturing costs, and suboptimal efficacy. CRISPR/Cas system, an efficient and simple method for precise gene editing, offers new possibilities for optimizing CAR-T cells. It can increase the function of CAR-T cells and reduce manufacturing costs. The combination of CRISPR/Cas9 technology and CAR-T cell therapy may promote the development of this therapy and provide more effective and personalized treatment for cancer patients. Meanwhile, the safety issues surrounding the application of this technology in CAR-T cells require further research and evaluation. Future research should focus on improving the accuracy and safety of CRISPR/Cas9 technology to facilitate the better development and application of CAR-T cell therapy. This review focuses on the application of CRISPR/Cas9 technology in CAR-T cell therapy, including eliminating the inhibitory effect of immune checkpoints, enhancing the ability of CAR-T cells to resist exhaustion, assisting in the construction of universal CAR-T cells, reducing the manufacturing costs of CAR-T cells, and the security problems faced. The objective is to show the revolutionary role of CRISPR/Cas9 technology in CAR-T cell therapy for researchers.
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Leucemia Linfocítica Crónica de Células B , Receptores Quiméricos de Antígenos , Humanos , Edición Génica , Sistemas CRISPR-Cas , Receptores Quiméricos de Antígenos/genética , Tecnología , Tratamiento Basado en Trasplante de Células y TejidosRESUMEN
Neural implicit function based on signed distance field (SDF) has achieved impressive progress in reconstructing 3D models with high fidelity. However, such approaches can only represent closed surfaces. Recent works based on unsigned distance function (UDF) are proposed to handle both watertight and single-layered open surfaces. Nonetheless, as UDF is signless, its direct output is limited to the point cloud, which imposes an additional challenge on extracting high-quality meshes from discrete points. To address this challenge, we present a novel neural implicit representation coded HSDF, which is a hybrid of signed and unsigned distance fields. In particular, HSDF is able to represent arbitrary topologies containing both closed and open surfaces while being compatible with existing iso-surface extraction techniques for easy field-to-mesh conversion. In addition to predicting a UDF, we propose to learn an additional sign field. Unlike traditional SDF, HSDF is able to locate the surface of interest before level surface extraction by generating surface points following NDF [1]. We are then able to obtain open surfaces via an adaptive meshing approach that only instantiates regions containing surfaces into a polygon mesh. HSDF benefits downstream tasks like neural rendering, as it enables the rendering of back-faces of open surfaces. We also propose HSDF-Net, a dedicated learning framework that factorizes the learning of HSDF into two easier sub-problems. Experiments and evaluations show that HSDF outperforms the state-of-the-art techniques both qualitatively and quantitatively on some of the used datasets.
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Chinese motherwort (Leonurus japonicus), a member of Lamiaceae family, is a commonly used medicinal herb for treating obstetrical and gynecological diseases, producing over 280 officinal natural products. Due to limited genomic resources, little progress has been made in deciphering the biosynthetic pathway of valuable natural products in L. japonicus. Here, we de novo assembled the L. japonicus genome using high-coverage ONT long reads and Hi-C reads. The chromosome-level genome assembly contained ten chromosomes representing 99.29% of 489.34 Mb genomic sequence with a contig and scaffold N50 of 7.27 Mb and 50.86 Mb, respectively. Genome validations revealed BUSCO and LAI score of 99.2% and 21.99, respectively, suggesting high quality of genome assembly. Using transcriptomic data from various tissues, 22,531 protein-coding genes were annotated. Phylogenomic analysis of 13 angiosperm plants suggested L. japonicus had 58 expanded gene families functionally enriched in specialized metabolism such as diterpenoid biosynthesis. The genome assembly, annotation, and sequencing data provide resources for the elucidation of biosynthetic pathways behind natural products of pharmaceutical applications in L. japonicus.
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Genoma de Planta , Leonurus , Productos Biológicos , China , Perfilación de la Expresión Génica , Genómica , Leonurus/genéticaRESUMEN
The degradability of hydrogels plays a pivotal role in bone regeneration, yet its precise effects on the bone repair process remain poorly understood. Traditional studies have been limited by the use of hydrogels with insufficient variation in degradation properties for thorough comparative analysis. Addressing this gap, our study introduces the development of matrix metalloproteinase (MMP)-responsive hydrogels engineered with a tunable degradation rate, specifically designed for bone regeneration applications. These innovative hydrogels are synthesized by integrating MMP-sensitive peptides, which exhibit chirality-transferred amino acids, with norbornene (NB)-modified 8-arm polyethylene glycol (PEG) macromers to form the hydrogel network. The degradation behavior of these hydrogels is manipulated through the chirality of the incorporated peptides, resulting in the classification into L, LD, and D hydrogels. Remarkably, the L hydrogel variant shows a significantly enhanced degradation rate, both in vitro and in vivo, which in turn fosters bone regeneration by promoting cell migration and upregulating osteogenic gene expression. This research highlights the fundamental role of hydrogel degradability in bone repair and lays the groundwork for the advancement of degradable hydrogel technologies for bone regeneration, offering new insights and potential for future biomaterials development.
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Chili pepper (Capsicum) is known for its unique fruit pungency due to the presence of capsaicinoids. The evolutionary history of capsaicinoid biosynthesis and the mechanism of their tissue specificity remain obscure due to the lack of high-quality Capsicum genomes. Here, we report two telomere-to-telomere (T2T) gap-free genomes of C. annuum and its wild nonpungent relative C. rhomboideum to investigate the evolution of fruit pungency in chili peppers. We precisely delineate Capsicum centromeres, which lack high-copy tandem repeats but are extensively invaded by CRM retrotransposons. Through phylogenomic analyses, we estimate the evolutionary timing of capsaicinoid biosynthesis. We reveal disrupted coding and regulatory regions of key biosynthesis genes in nonpungent species. We also find conserved placenta-specific accessible chromatin regions, which likely allow for tissue-specific biosynthetic gene coregulation and capsaicinoid accumulation. These T2T genomic resources will accelerate chili pepper genetic improvement and help to understand Capsicum genome evolution.
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Capsaicina , Capsicum , Evolución Molecular , Genoma de Planta , Filogenia , Telómero , Capsicum/genética , Capsicum/metabolismo , Capsaicina/metabolismo , Telómero/genética , Telómero/metabolismo , Frutas/genética , Frutas/metabolismo , Retroelementos/genética , Regulación de la Expresión Génica de las PlantasRESUMEN
BACKGROUND AND PURPOSE: Protein palmitoylation is involved in learning and memory, and in emotional disorders. Yet, the underlying mechanisms in these processes remain unclear. Herein, we describe that A-kinase anchoring protein 150 (AKAP150) is essential and sufficient for depressive-like behaviours in mice via a palmitoylation-dependent mechanism. EXPERIMENTAL APPROACH: Depressive-like behaviours in mice were induced by chronic restraint stress (CRS) and chronic unpredictable mild stress (CUMS). Palmitoylated proteins in the basolateral amygdala (BLA) were assessed by an acyl-biotin exchange assay. Genetic and pharmacological approaches were used to investigate the role of the DHHC2-mediated AKAP150 palmitoylation signalling pathway in depressive-like behaviours. Electrophysiological recording, western blotting and co-immunoprecipitation were performed to define the mechanistic pathway. KEY RESULTS: Chronic stress successfully induced depressive-like behaviours in mice and enhanced AKAP150 palmitoylation in the BLA, and a palmitoylation inhibitor was enough to reverse these changes. Blocking the AKAP150-PKA interaction with the peptide Ht-31 abolished the CRS-induced AKAP150 palmitoylation signalling pathway. DHHC2 expression and palmitoylation levels were both increased after chronic stress. DHHC2 knockdown prevented CRS-induced depressive-like behaviours, as well as attenuating AKAP150 signalling and synaptic transmission in the BLA in CRS-treated mice. CONCLUSION AND IMPLICATIONS: These results delineate that DHHC2 modulates chronic stress-induced depressive-like behaviours and synaptic transmission in the BLA via the AKAP150 palmitoylation signalling pathway, and this pathway may be considered as a promising novel therapeutic target for major depressive disorder.