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Given the growing emphasis on energy efficiency, environmental sustainability, and agricultural demand, there's a pressing need for decentralized and scalable ammonia production. Converting nitrate ions electrochemically, which are commonly found in industrial wastewater and polluted groundwater, into ammonia offers a viable approach for both wastewater treatment and ammonia production yet limited by low producibility and scalability. Here we report a versatile and scalable solution-phase synthesis of high-entropy single-atom nanocages (HESA NCs) in which Fe and other five metals-Co, Cu, Zn, Cd, and In-are isolated via cyano-bridges and coordinated with C and N, respectively. Incorporating and isolating the five metals into the matrix of Fe resulted in Fe-C5 active sites with a minimized symmetry of lattice as well as facilitated water dissociation and thus hydrogenation process. As a result, the Fe-HESA NCs exhibited a high selectivity toward NH3 from the electrocatalytic reduction of nitrate with a Faradaic efficiency of 93.4% while maintaining a high yield rate of 81.4 mg h-1 mg-1.
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BACKGROUND: The therapeutic potential of adipose-derived mesenchymal stromal cells (AMSCs) in the treatment of intestinal fibrosis occured in patients with Crohn's disease (CD) remains unclear. Tumor necrosis factor-stimulated gene 6 (TSG6) protein plays a critical role in inflammation regulation and tissue repair. This study aimed to determine if AMSCs attenuate intestinal fibrosis by secreting paracrine TSG6 protein and explore the underlying mechanisms. METHODS: Two murine models for intestinal fibrosis were established using 2,4,6-trinitrobenzene sulfonic acid in BALB/c mice and dextran sulfate sodium in C57BL/6 mice. Primary human fibroblasts and CCD-18co cells were incubated with transforming growth factor (TGF)-ß1 to build two fibrosis cell models in vitro. RESULTS: Intraperitoneally administered AMSCs attenuated intestinal fibrosis in the two murine models, as evidenced by significant alleviation of colon shortening, collagen protein deposits, and submucosal thickening, and also decrease in the endoscopic and fibrosis scores (P < 0.001). Although intraperitoneally injected AMSCs did not migrate to the colon lesions, high levels of TSG6 expression and secretion were noticed both in vivo and in vitro. Similar to the role of AMSCs, injection of recombinant human TSG6 attenuated intestinal fibrosis in the mouse models, which was not observed with the administration of AMSCs with TSG6 knockdown or TSG6 neutralizing antibody. Mechanistically, TSG6 alleviates TGF-ß1-stimulated upregulation of α-smooth muscle actin (αSMA) and collagen I by inhibiting Smad2 phosphorylation. Furthermore, the expression of TSG6 is lower in intestinal fibrosis tissue of patients with Crohn's disease and can reduce pro-fibrotic protein (αSMA) secretion from primary ileal fibrotic tissue. CONCLUSIONS: AMSCs attenuate intestinal fibrosis by secreting paracrine TSG6 protein, which inhibits Smad2 phosphorylation. TSG6, a novel anti-fibrotic factor, could potentially improve intestinal fibrosis treatments.
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Moléculas de Adhesión Celular , Enfermedad de Crohn , Modelos Animales de Enfermedad , Fibrosis , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Proteína Smad2 , Animales , Humanos , Células Madre Mesenquimatosas/metabolismo , Moléculas de Adhesión Celular/metabolismo , Moléculas de Adhesión Celular/genética , Enfermedad de Crohn/terapia , Enfermedad de Crohn/patología , Enfermedad de Crohn/metabolismo , Ratones , Proteína Smad2/metabolismo , Masculino , Sulfato de Dextran , Ácido Trinitrobencenosulfónico , Tejido Adiposo/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Células Cultivadas , Femenino , Fibroblastos/metabolismo , Colon/patología , Colon/metabolismo , Colitis/inducido químicamente , Colitis/terapia , Colitis/patologíaRESUMEN
Perovskite oxides are proven as a striking platform for developing high-performance electrocatalysts. Nonetheless, a significant portion of them show CO2 electroreduction (CO2RR) inertness. Here a simple but effective strategy is reported to activate inert perovskite oxides (e.g., SrTiO3) for CO2RR through slight Cu2+ doping in B-sites. For the proof-of-concept catalysts of SrTi1-xCuxO3 (x = 0.025, 0.05, and 0.1), Cu2+ doping (even in trace amount, e.g., x = 0.025) can not only create active, stable CuO6 octahedra, increase electrochemical active surface area, and accelerate charge transfer, but also significantly regulate the electronic structure (e.g., up-shifted band center) to promote activation/adsorption of reaction intermediates. Benefiting from these merits, the stable SrTi1-xCuxO3 catalysts feature great improvements (at least an order of magnitude) in CO2RR activity and selectivity for high-order products (i.e., CH4 and C2+), compared to the SrTiO3 parent. This work provides a new avenue for the conversion of inert perovskite oxides into high-performance electrocatalysts toward CO2RR.
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Spinal Cord Injury (SCI) is a debilitating disease associated with a significant economic burden owing to its high level of disability; however, current treatment options have only limited efficacy. Past research has shown that iron-dependent programmed cell death, also known as ferroptosis, plays a critical role in the pathogenesis of SCI. The sigma-1 receptor (Sig-1R) is widely distributed in the central nervous system, and has been implicated in the pathophysiology of several neurological and psychiatric disorders. Several in vivo and ex vivo studies have shown that Sig-1R activation exerts unique neuroprotective effects. However, the underlying mechanisms remain unclear. To date, no study has yet demonstrated the association between Sig-1R activation and ferroptosis in patients with SCI. However, the present study found that Sig-1R activation effectively promoted the recovery of motor function in mice after spinal cord injury, attenuated neuronal apoptosis, reduced the production of pro-inflammatory cytokines and iron accumulation, and inhibited ferroptosis in spinal cord tissues following SCI in mice. Ferroptosis and IRE1α were significantly upregulated after spinal cord injury, while sigma-1 receptor agonists were able to facilitate this result through the elimination of inositol-requiring enzyme-1 alpha (IRE1α)-mediated neuronal ferroptosis. Therefore, sigma-1 receptor activation could attenuate ferroptosis after SCI by reducing IRE1α and improving functional recovery after SCI, potentially representing a new therapeutic strategy for treating SCI.
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Ferroptosis , Ratones Endogámicos C57BL , Neuronas , Proteínas Serina-Treonina Quinasas , Receptores sigma , Receptor Sigma-1 , Traumatismos de la Médula Espinal , Traumatismos de la Médula Espinal/metabolismo , Animales , Receptores sigma/metabolismo , Receptores sigma/agonistas , Ferroptosis/fisiología , Ferroptosis/efectos de los fármacos , Ratones , Proteínas Serina-Treonina Quinasas/metabolismo , Neuronas/metabolismo , Endorribonucleasas/metabolismo , Masculino , Recuperación de la Función/fisiología , Recuperación de la Función/efectos de los fármacos , Apoptosis/fisiología , Apoptosis/efectos de los fármacos , Médula Espinal/metabolismoRESUMEN
The electrochemical nitrate reduction reaction (NO3RR) holds promise for converting nitrogenous pollutants to valuable ammonia products. However, conventional electrocatalysis faces challenges in effectively driving the complex eight-electron and nine-proton transfer process of the NO3RR while also competing with the hydrogen evolution reaction. In this study, we present the thermally enhanced electrocatalysis of nitrate-to-ammonia conversion over nickel-modified copper oxide single-atom alloy oxide nanowires. The catalyst demonstrates improved ammonia production performance with a Faradaic efficiency of approximately 80% and a yield rate of 9.7 mg h-1 cm-2 at +0.1 V versus a reversible hydrogen electrode at elevated cell temperatures. In addition, this thermally enhanced electrocatalysis system displays impressive stability, interference resistance, and favorable energy consumption and greenhouse gas emissions for the simulated industrial wastewater treatment. Complementary in situ analyses confirm that the significantly superior relay of active hydrogen species formed at Ni sites facilitates the thermal-field-coupled electrocatalysis of Cu surface-adsorbed *NOx hydrogenation. Theoretical calculations further support the thermodynamic and kinetic feasibility of the relay catalysis mechanism for the NO3RR over the Ni1Cu model catalyst. This study introduces a conceptual thermal-electrochemistry approach for the synergistic regulation of complex catalytic processes, highlighting the potential of multifield-coupled catalysis to advance sustainable-energy-powered chemical synthesis technologies.
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OBJECTIVE: The mechanism behind SDAVF is still unclear. We discovered that the vessel wall of the SDAVF-DV occasionally showed enhancement in MRI, and this study assessed the relationship between the enhancement of the draining vein's wall and its histology. METHODS: For histopathologic analysis, 16 draining vein samples from 16 patients with SDAVF were included, 3 normal arteries and 3 normal veins were chosen as comparison. We assessed the imaging and microscopic characteristics of the draining veins in SDAVF patients. The former included the presence of significant enhancement of the wall of the draining vein in MRI, and the latter included the adherence, aggregation, infiltration of pro-inflammatory factors and inflammatory cells. Immuno-histochemical staining was performed using IL-1ß, IL-8, TGF-ß as well as MPO and MMP-9, and positive results were counted. Multiple logistic regression analysis was used to determine whether the infiltration of inflammatory cells was connected to vessel wall enhancement in the SDAVF-DV. RESULTS: Infiltration of inflammatory cells was significantly higher in SDAVF-DV compared to normal vessels, 7 out of 16 patients significantly had enhancement of the vessel wall of SDAVF-DV, and logistic regression analysis showed that samples with more infiltration of inflammatory cells were more likely to show enhancement of the SDAVF-DV walls. CONCLUSION: There was considerable inflammatory cells infiltration in SDAVF-DV, and this may explain why their vessel wall had such a significant enhancement in MRI.
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Malformaciones Vasculares del Sistema Nervioso Central , Imagen por Resonancia Magnética , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/patología , Imagen por Resonancia Magnética/métodos , Adulto , Venas/patología , Venas/diagnóstico por imagen , Médula Espinal/diagnóstico por imagen , Médula Espinal/patología , Médula Espinal/irrigación sanguíneaRESUMEN
Electrocatalysts comprised of Pt-Ni alloy nanocrystals have garnered substantial attention due to their outstanding performance in catalyzing the oxygen reduction reaction (ORR). Herein, we present the synthesis of Pt-Ni nanocrystals with a variety of controlled shapes and compositions in an effort to investigate the impact of the Ni content on the formation of {111} facets and thereby the ORR activity. By completely excluding O2 from the reaction system, we could prevent the generation of Ni(OH)2 on the surface of the nanocrystals and thereby achieve a linear relationship between the atomic ratio of Pt to Ni in the nanocrystals and the feeding ratio of the precursors. The atomic ratio of Pt to Ni in the Pt-Ni nanocrystals was tunable within the range of 1.2-7.2, while their average sizes were kept around 9 nm in terms of edge length. In addition, a quantitative correlation between the area ratio of {111} to {100} facets and the feeding ratio of Pt(II) to Ni(II) was obtained by adjusting the mole fraction of the Ni(II) precursor in the reaction mixture. For the catalysts comprising octahedral nanocrystals, their specific ORR activities exhibited a positive correlation with the Pt/Ni atomic ratio. After the accelerated durability test, both specific and mass activity displayed a volcano-type trend with a peak value at a Pt/Ni atomic ratio of 1.6.
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The selective two-electron electrochemical oxygen reduction reaction (ORR) for hydrogen peroxide (H2O2) production is a promising and green alternative method to the current energy-intensive anthraquinone process used in industry. In this study, we develop a single-atom catalyst (CNT-D-O-Fe) by anchoring defect-stabilized and oxygen-coordinated iron atomic sites (Fe-O4) onto porous carbon nanotubes using a local etching strategy. Compared to O-doped CNTs with vacancy defects (CNT-D-O) and oxygen-coordinated Fe single-atom site modifying CNTs without a porous structure (CNT-O-Fe), CNT-D-O-Fe exhibits the highest H2O2 selectivity of 94.4% with a kinetic current density of 13.4 mA cm-2. Fe-O4 single-atom sites in the catalyst probably contribute to the intrinsic reactivity for the two-electron transfer process while vacancy defects greatly enhance the electrocatalytic stability. Theoretical calculations further support that the coordinated environment and defective moiety in CNT-D-O-Fe could efficiently optimize the adsorption strength of the *OOH intermediate over the Fe single atomic active sites. This contribution sheds light on the potential of defect-stabilized and oxygen-coordinated single-atom metal sites as a promising avenue for the rational design of highly efficient and selective catalysts towards various electrocatalytic reactions.
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BACKGROUND: Recurrences are the main reasons for unfavorable outcomes for patients with stage II colorectal cancer (CRC). To obtain a clear understanding of the high-risk factors, further investigation is warranted. The present study aimed to analyze the risk factors associated with postoperative recurrence in patients with stage II CRC. METHODS: Eligible patients with pathologically confirmed stage II CRC were enrolled in the study retrospectively based on a prospectively maintained database from April 2008 to March 2019. The Kaplan-Meier method were used to calculate the overall survival (OS) rate and the cumulative recurrence rate. Univariate and multivariable Cox regression analyses were performed to identify risk factors for recurrence. RESULTS: There were 2515 patients included, of whom 233 (9.3%) developed local or distant recurrence. Recurrence was associated with a significantly worse 5-year OS (45.4% vs. 95.5%, p < 0.0001). The 5-year cumulative recurrence rate was 13.0% in patients with stage II CRC. On multivariable Cox analysis, tumor size (Hazard Ratio (HR) [95% confidence interval (CI)] = 1.79[1.38, 2.33]), preoperative carbohydrate antigen (CA) 125 level (HR [95% CI] = 1.78[1.17, 2.70]), preoperative CA 199 level (HR [95% CI] = 1.56[1.09, 2.22]), and ulcerating tumor (HR [95% CI] = 1.61[1.19, 2.17]) were found to be associated with postoperative recurrence. Adjuvant chemotherapy was associated with a lower cumulative recurrence rate in patients with these risk factors (p = 0.00096). CONCLUSION: The tumor diameter, preoperative CA125 level, preoperative CA199 level, and an ulcerative tumor can predict postoperative recurrence in patients with stage II CRC, and postoperative chemotherapy could reduce the cumulative recurrence rate in patients with these high-risk factors.
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Neoplasias Colorrectales , Humanos , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias Colorrectales/patología , Factores de Riesgo , Recurrencia Local de Neoplasia/patologíaRESUMEN
Harvesting recyclable ammonia (NH3) from the electrocatalytic reduction of nitrate (NO3RR) offers a sustainable strategy to close the ecological nitrogen cycle from nitration contamination in an energy-efficient and environmentally friendly manner. The emerging intermetallic single-atom alloys (ISAAs) are recognized to achieve the highest site density of single atoms by isolating contiguous metal atoms into single sites stabilized by another metal within the intermetallic structure, which holds promise to couple the catalytic benefits from intermetallic nanocrystals and single-atom catalysts for promoting NO3RR. Herein, ISAA In-Pd bimetallene, in which the Pd single atoms are isolated by surrounding In atoms, is reported to boost neutral NO3RR with a NH3 Faradaic efficiency (FE) of 87.2%, a yield rate of 28.06 mg h-1 mgPd-1, and an exceptional electrocatalytic stability with increased activity/selectivity over 100 h and 20 cycles. The ISAA structure induces substantially diminished overlap of Pd d-orbitals and narrowed p-d hybridization of In-p and Pd-d states around the Fermi level, resulting in a stronger NO3- adsorption and a depressed energy barrier of the potential-determining step for NO3RR. Further integrating the NO3RR catalyst into a Zn-NO3- flow battery as the cathode delivers a power density of 12.64 mW cm-2 and a FE of 93.4% for NH3 production.
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Anthropogenic nitrate pollution has an adverse impact on the environment and human health. As part of a sustainable nitrate management strategy, electrochemical denitrification is studied as an innovative strategy for nutrients recycling and recovering. It is, however, challenging to selectively electro-reduce nitrate with low-concentration for ammonia. Herein, the photo-deposition of size-defined Ru nanoclusters (NCs, average size: ≈1.66 nm) on TiO2 nanotubes (NTs) is demonstrated, which show improved performance for nitrate-to-ammonia electroreduction with a maximum yield rate of ≈600 µg h-1 cm-2 and a faradic efficiency (FE) of > 90.0% across a broad range of potentials in comparison with electrodeposited Ru nanoparticles (NPs, average size: ≈23.78 nm) on TiO2 NTs. Experimental and theoretical evidence further suggests the small-size Ru NCs with the intrinsically enhanced selectivity and activity because of the strong metal/substrate interaction and unsaturated coordination state. The findings highlight the size effect on Ru-based catalyst supported on metal oxides, a versatile catalytic model, which allows the regulation of hydrogen adsorption to favor ammonia production over the competing hydrogen evolution reaction.
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Electroreduction of nitrate to ammonia offers a promising pathway for nutrient recycling and recovery from wastewater with energy and environmental sustainability. There have been considerable efforts on the regulation of reaction pathways to facilitate nitrate-to-ammonia conversion over the competing hydrogen evolution reaction but only with limited success. Here, we report a Cu single-atom gel (Cu SAG) electrocatalyst that produces NH3 from both nitrate and nitrite under neutral conditions. Given the unique mechanism of NO2- activation on Cu SAGs with spatial confinement and strengthened kinetics, a pulse electrolysis strategy is presented to cascade the accumulation and conversion of NO2- intermediates during NO3- reduction with the prohibited competition from the hydrogen evolution reaction, thus substantially enhancing the Faradaic efficiency and the yield rate for ammonia production compared with constant potential electrolysis. This work underlines the cooperative approach of the pulse electrolysis and SAGs with three-dimensional (3D) framework structures for highly efficient nitrate-to-ammonia conversion enabled by tandem catalysis of unfavorable intermediates.
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The inferior activity and stability of non-noble metal-based electrocatalysts for oxygen evolution reaction (OER) seriously limit their practical applications in various electrochemical energy conversion systems. Here we report, a drastic nonequilibrium precipitation approach to construct a highly disordered crystal structure of layered double hydroxides as a model OER catalyst. The unconventional crystal structure contains high-density cationic defects coupled with a local alkaline-enriched environment, enabling ultrafast diffusion of OH- ions and thus avoiding the formation of a local acidic environment and dissolution of active sites during OER. An integrated experimental and theoretical study reveals that high-density cationic defects, especially di-cationic and multi-cationic defects, serve as highly active and durable catalytic sites. This work showcases a promising strategy of crystal structure engineering to construct robust active sites for high-performance oxygen evolution in an alkaline solution.
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Oxígeno , Agua , Cationes , Oxidación-Reducción , DifusiónRESUMEN
Automatic breast ultrasound image segmentation helps radiologists to improve the accuracy of breast cancer diagnosis. In recent years, the convolutional neural networks (CNNs) have achieved great success in medical image analysis. However, it exhibits limitations in modeling long-range relations, which is unfavorable for ultrasound images with speckle noise and shadows, resulting in decreased accuracy of breast lesion segmentation. Transformer can obtain sufficient global information, but it is deficient in acquiring local details and needs to be pre-trained on large-scale datasets. In this paper, we propose a Hybrid CNN-Transformer network (HCTNet) for boosting the breast lesion segmentation in ultrasound images. In the encoder of HCTNet, Transformer Encoder Blocks (TEBlocks) are designed to learn the global contextual information, which are combined with CNNs to extract features. In the decoder of HCTNet, a Spatial-wise Cross Attention (SCA) module is developed based on the spatial attention mechanism, which reduces the semantic discrepancy with the encoder. Moreover, residual connection is used between decoder blocks to make the generated features more discriminative by aggregating contextual feature maps at different semantic scales. Extensive experiments on three public breast ultrasound datasets demonstrate that HCTNet outperforms other medical image segmentation methods and the recent semantic segmentation methods on breast ultrasound lesion segmentation.
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Aprendizaje , Redes Neurales de la Computación , Humanos , Radiólogos , Semántica , Procesamiento de Imagen Asistido por ComputadorRESUMEN
We report a robust method for the facet-controlled synthesis of nanocrystals with an ultrathin shell made of a nearly equimolar RuRhPdPt quaternary alloy. Our strategy involves the use of well-defined Rh cubic seeds, halide-free precursors, and a method for precisely controlling the reaction kinetics of different precursors. In the setting of dropwise addition, the precursors with different reactivities can be reduced at about the same pace for the generation of an alloy with a uniform and well-controlled composition. The core-shell nanocubes show greatly enhanced activity toward ethanol oxidation when benchmarked against Pd and Pt counterparts. Combining in situ and ex situ electron microscopy studies, we also demonstrate that the core-shell nanocubes possess good thermal and electrochemical stability in terms of both geometrical shape and elemental composition, with their cubic shape and alloy composition retained when annealing at 500 °C or after long-term electrochemical cycling. It is expected that the synthetic approach can be further extended to fabricate multimetallic catalysts with enhanced activities toward a variety of thermal and electrochemical reactions.
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As a member of graphene analogs, metallenes are a class of two-dimensional materials with atomic thickness and well-controlled surface atomic arrangement made of metals or alloys. When utilized as catalysts, metallenes exhibit distinctive physicochemical properties endowed from the under-coordinated metal atoms on the surface, making them highly competitive candidates for energy-related electrocatalysis and energy conversion systems. Significantly, their catalytic activity can be precisely tuned through the chemical modification of their surface and subsurface atoms for efficient catalyst engineering. This minireview summarizes the recent progress in the synthesis and characterization of metallenes, together with their use as electrocatalysts toward reactions for energy conversion. In the Synthesis section, we pay particular attention to the strategies designed to tune their exposed facets, composition, and surface strain, as well as the porosity/cavity, defects, and crystallinity on the surface. We then discuss the electrocatalytic properties of metallenes in terms of oxygen reduction, hydrogen evolution, alcohol and acid oxidation, carbon dioxide reduction, and nitrogen reduction reaction, with a small extension regarding photocatalysis. At the end, we offer perspectives on the challenges and opportunities with respect to the synthesis, characterization, modeling, and application of metallenes.
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BACKGROUND: Physical activity at pre-older ages (55-64 years) can greatly affect one's physical fitness, health, physical-activity behaviour, and quality of life at older ages. The objective of this study was to conduct a 24-week walking-exercise programme among sedentary pre-older females and investigate the influence of different walking cadences on cardiorespiratory fitness and associated biomarkers. METHODS: A total of 78 pre-older sedentary female participants were recruited and randomly assigned to normal (n = 36), paced (n = 15), music-synchronised (n = 15) walking, and no-exercise control (n = 12) groups, respectively. The normal, paced, and music-synchronised walking groups walked at a cadence of 120 steps/min, 125 steps/min, and 120-128 steps/min, respectively, under supervised conditions. Anthropometric characteristics, step length, nutrient intake, blood pressure and composition, and cardiorespiratory fitness were measured at baseline, the 12th week of the programme, the 24th week of the programme (completion), and after a 12-week retention period, which began immediately upon completion of the programme and did not feature any supervised exercises. RESULTS: All walking conditions improved high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, step length, maximum oxygen consumption (VO2max), and oxidative capacity at anaerobic threshold (all P < 0.001); however, after the 12-week retention period only the training effects of HDL-C (P < 0.05) and VO2max (P < 0.05) remained robust. Additionally, music-synchronised walking was found to reduce the fat ratio (P = 0.031), while paced walking was found to reduce body mass (P = 0.049). CONCLUSIONS: The significant pre-post changes in health-related outcomes across the 24-week walking intervention, including improved blood composition, longer step length, and better cardiorespiratory capacity, show that this intervention is promising for improving health and fitness. When, during the retention period, the participants resumed their usual lifestyles without supervised exercise, most physiological biomarkers deteriorated. Thus, for sedentary middle-aged females, persistent behavioural change is necessary to retain the health benefits of physical exercise.
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Música , Calidad de Vida , Humanos , Femenino , Persona de Mediana Edad , Caminata/fisiología , Aptitud Física/fisiología , ColesterolRESUMEN
As an emerging class of materials with distinctive physicochemical properties, metallenes are deemed as efficient catalysts for energy-related electrocatalytic reactions. Engineering the lattice strain, electronic structure, crystallinity, and even surface porosity of metallene provides a great opportunity to further enhance its catalytic performance. Herein, we rationally developed a reconstruction strategy of Pd metallenes at atomic scale to generate a series of nonmetallic atom-intercalated Pd metallenes (M-Pdene, M = H, N, C) with lattice expansion and S-doped Pd metallene (S-Pdene) with an amorphous structure. Catalytic performance evaluation demonstrated that N-Pdene exhibited the highest mass activities of 7.96 A mg-1, which was 10.6 and 8.5 time greater than those of commercial Pd/C and Pt/C, respectively, for methanol oxidation reaction (MOR). Density functional theory calculations suggested that the well-controlled lattice tensile strain as well as the strong p-d hybridization interaction between N and Pd resulted in enhanced OH adsorption and weakened CO adsorption for efficient MOR catalysis on N-Pdene. When tested as hydrogen evolution reaction (HER) catalysts, the amorphous S-Pdene delivered superior activity and durability relative to the crystalline counterparts because of the disordered Pd surface with a further elongated bond length and a downshifted d-band center. This work provides an effective strategy for atomic engineering of metallene nanomaterials with high performance as electrocatalysts.
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BACKGROUND: Patients with ulcerative colitis are at an increased risk of developing colorectal cancer with a prolonged disease course. Many studies have shown that alterations in the immune microenvironment play a key role in ulcerative colitis-associated colorectal cancer. Additionally, competing endogenous RNAs have important functions in immunoregulation, affecting inflammation and tumorigenesis. However, the complexity and behavioral characteristics of the competing endogenous RNA immunoregulatory network in ulcerative colitis-associated colorectal cancer remain unclear. We constructed a competing endogenous RNA immunoregulatory network to discover and validate a novel competing endogenous RNA immunoregulatory axis to provide insight into ulcerative colitis-associated colorectal cancer progression. METHODS: The competing endogenous RNA immunoregulatory network was constructed using differential expression analysis, weighted gene co-expression network analysis, and immune-related genes. Cmap was used to identify small-molecule drugs with therapeutic potential in ulcerative colitis-associated colorectal cancer. The ulcerative colitis-associated colorectal cancer-related pathways were identified by gene set variation and enrichment analysis. CIBERSORT, single-sample Gene Set Enrichment Analysis, and xCell were used to evaluate the infiltration of immune cells and screen hub immunocytes. The competing endogenous RNA immunoregulatory axis was identified by correlation analysis. RESULTS: We identified 130 hub immune genes and constructed a competing endogenous RNA immunoregulatory network consisting of 56 long non-coding RNAs, four microRNAs, and six targeted hub immune genes. Four small-molecule drugs exerted potential therapeutic effects by reversing the expression of hub immune genes. Pathway analysis showed that the NF-κB pathway was significantly enriched. Neutrophils were identified as hub immunocytes, and IL6ST was significantly positively correlated with the neutrophil count. In addition, NEAT1 may serve as a competing endogenous RNA to sponge miR-1-3p and promote IL6ST expression. CONCLUSIONS: The competing endogenous RNA immunoregulatory axis may regulate neutrophil infiltration, affecting the occurrence of ulcerative colitis-associated colorectal cancer.
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Colitis Ulcerosa , Neoplasias Asociadas a Colitis , MicroARNs , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/genética , Neoplasias Asociadas a Colitis/genética , Redes Reguladoras de Genes , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Mensajero/genética , Microambiente Tumoral/genéticaRESUMEN
BACKGROUND: The clinical characteristics of synchronous colorectal cancer (SCRC) reported in previous studies differ significantly. Furthermore, little is known about the characteristics of early-onset synchronous colorectal cancer (EO-SCRC). The aim of this retrospective study was to identify the clinicopathological characteristics of SCRC and EO-SCRC and define their relevant prognostic factors. METHODS: Patients who underwent surgery for SCRC and primary unifocal colorectal cancer (PCRC) between January 2007 and December 2020 were included in this study. The clinical, histological, and molecular characteristics of the patient's tumours were analysed. The primary endpoint was overall survival (OS). Univariate and multivariate Cox regression analyses were used to assess the association between clinicopathological factors and patient survival. RESULTS: A total of 1554 patients were included in the analysis. Of these, 1132 (72.84%) had PCRC and 422 (27.16%) had SCRC. SCRC occurred more frequently in the elderly (P < 0.001) and in male patients (P = 0.002). The 5-year OS rate was 73.7% ± 2.0% for PCRC and 61.9% ± 3.9% for SCRC (P < 0.05). However, the Cox regression analysis showed that SCRC was not an independent prognostic factor for the prediction of OS. A total of 64 patients (15.17%) in the SCRC group had early-onset colorectal cancer (EOCRC), whereas 257 (22.70%) in the PCRC group had EOCRC (P = 0.001). The proportion of patients with deficient mismatch repair proteins (dMMR) in EO-SCRC subgroup was significantly higher than that in late-onset synchronous colorectal cancer (LO-SCRC) subgroup (23.44% vs. 10.34%, P = 0.006). Patients with EO-SCRC had more TNM stage IV (P < 0.001) and fewer opportunities for radical surgery (79.69% vs. 92.22%, P = 0.007) than those with early-onset primary unifocal colorectal cancer (EO-PCRC). There was no significant difference in 5-year OS between the EO-SCRC and LO-SCRC subgroups (P = 0.091) and between the EO-SCRC and EO-PCRC subgroups (P = 0.094). Multivariate analysis revealed that EOCRC was an independent good prognostic parameter for colorectal cancer (CRC) and SCRC. CONCLUSION: For patients with operative treatment, EO-SCRC is different from LO-SCRC and EO-PCRC. Patients with SCRC show a poorer survival rate than those with PCRC. However, SCRC is not an independent prognostic factor for CRC, whereas EOCRC is a good prognostic factor for CRC and SCRC.