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Background: Cancer cells are capable of evading clearance by macrophages through overexpression of anti-phagocytic surface proteins known as "don't eat me" signals. Monoclonal antibodies that antagonize the "don't-eat-me" signaling in macrophages and tumor cells by targeting phagocytic checkpoints have shown therapeutic promises in several cancer types. However, studies on the responses to these drugs have revealed the existence of other unknown "don't eat me" signals. Moreover, identification of key molecules and interactions regulating macrophage phagocytosis is required for tumor therapy. Methods: CRISPR screen was used to identify genes that impede macrophage phagocytosis. To explore the function of Vtn and C1qbp in phagocytosis, knockdown and subsequent functional experiments were conducted. Flow cytometry were performed to explore the phagocytosis rate, polarization of macrophage, and immune microenvironment of mouse tumor. To explore the underlying molecular mechanisms, RNA sequencing, immunoprecipitation, mass spectrometry, and immunofluorescence were conducted. Then, in vivo experiments in mouse models were conducted to explore the probability of Vtn knockdown combined with anti-CD47 therapy in breast cancer. Single-cell sequencing data from the Gene Expression Omnibus from The Cancer Genome Atlas database were analyzed. Results: We performed a genome-wide CRISPR screen to identify genes that impede macrophage phagocytosis, followed by analysis of cell-to-cell interaction databases. We identified a ligand-receptor pair of Vitronectin (Vtn) and complement C1Q binding protein (C1qbp) in tumor cells or macrophages, respectively. We demonstrated tumor cell-secreted Vtn interacts with C1qbp localized on the cell surface of tumor-associated macrophages, inhibiting phagocytosis of tumor cells and shifting macrophages towards the M2-like subtype in the tumor microenvironment. Mechanistically, the Vtn-C1qbp axis facilitated FcγRIIIA/CD16-induced Shp1 recruitment, which reduced the phosphorylation of Syk. Furthermore, the combination of Vtn knockdown and anti-CD47 antibody effectively enhanced phagocytosis and infiltration of macrophages, resulting in a reduction of tumor growth in vivo. Conclusions: This work has revealed that the Vtn-C1qbp axis is a new anti-phagocytic signal in tumors, and targeting Vtn and its interaction with C1qbp may sensitize cancer to immunotherapy, providing a new molecular target for the treatment of triple-negative breast cancer.
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Antígeno CD47 , Proteínas Portadoras , Macrófagos , Fagocitosis , Animales , Femenino , Humanos , Ratones , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/genética , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Antígeno CD47/metabolismo , Antígeno CD47/genética , Comunicación Celular , Línea Celular Tumoral , Macrófagos/metabolismo , Macrófagos/inmunología , Ratones Endogámicos BALB C , Proteínas Mitocondriales , Transducción de Señal/efectos de los fármacos , Microambiente Tumoral/inmunología , Microambiente Tumoral/efectos de los fármacosRESUMEN
Two-dimensional (2D) materials with a pentagonal structure have many unique physical properties and great potential for applications in electrical, thermal, and optical fields. In this paper, the intrinsic thermal transport properties of 2D pentagonal CX2 (X = N, P, As, and Sb) are comparatively investigated. The results show that penta-CN2 has a high thermal conductivity (302.7 W/mK), while penta-CP2, penta-CAs2, and penta-CSb2 have relatively low thermal conductivities of 60.0, 36.9, and 11.8 W/mK, respectively. The main reason for the high thermal conductivity of penta-CN2 is that the small atomic mass of the N atom is comparable to that of the C atom, resulting in a preferable pentagonal structure with stronger bonds and thus a higher phonon group velocity. The reduction in the thermal conductivity of the other three materials is mainly due to the gradually increased atomic mass from P to Sb, which reduces the phonon group velocity. In addition, the large atomic mass difference does not result in a huge enhancement of the anharmonicity or weakening of the phonon relaxation time. The present work is expected to deepen the understanding of the thermal transport of main group V 2D pentagonal carbons and pave the way for their future applications, also, providing ideas for finding potential thermal management materials.
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The high energy density and cost-effectiveness of chloride-ion batteries (CIBs) make them promising alternatives to lithium-ion batteries. However, the development of CIBs is greatly restricted by the lack of compatible electrolytes to support cost-effective anodes. Herein, we present a rationally designed solid polycationic electrolyte (SPE) to enable room-temperature chloride-ion batteries utilizing aluminum (Al) metal as an anode. This SPE endows the CIB configuration with improved air stability and safety (i.e. free of flammability and liquid leakage). A high ionic conductivity (1.3×10-2â S cm-1 at 25 °C) has been achieved by the well-tailored coordination structure of the SPE. Meanwhile, the solid polycationic electrolyte ensures stable electrodes|electrolyte interfaces, which effectively inhibit the growth of dendrites on the Al anodes and degradation of the FeOCl cathodes. The Al|SPE|FeOCl chloride-ion batteries showcased a high discharge capacity around 250â mAh g-1 (based on the cathodes) and extended lifespan. Our electrolyte design opens a new avenue for developing low-cost chloride-ion batteries.
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The effective flow of electrons through bulk electrodes is crucial for achieving high-performance batteries, although the poor conductivity of homocyclic sulfur molecules results in high barriers against the passage of electrons through electrode structures. This phenomenon causes incomplete reactions and the formation of metastable products. To enhance the performance of the electrode, it is important to place substitutable electrification units to accelerate the cleavage of sulfur molecules and increase the selectivity of stable products during charging and discharging. Herein, we develop a single-atom-charging strategy to address the electron transport issues in bulk sulfur electrodes. The establishment of the synergistic interaction between the adsorption model and electronic transfer helps us achieve a high level of selectivity towards the desirable short-chain sodium polysulfides during the practical battery test. These finding indicates that the atomic manganese sites have an enhanced ability to capture and donate electrons. Additionally, the charge transfer process facilitates the rearrangement of sodium ions, thereby accelerating the kinetics of the sodium ions through the electrostatic force. These combined effects improve pathway selectivity and conversion to stable products during the redox process, leading to superior electrochemical performance for room temperature sodium-sulfur batteries.
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OBJECTIVE: This cross-sectional study examined the socio-ecological factors influencing fundamental motor skills (FMS) in Chinese school-aged children. METHODS: A total of 1012 parent-child pairs were randomly sampled between March-1st and April-15th, 2022. Based on the socio-ecological model of Children's FMS, three levels of factors: individual-level (e.g., demographic, physical, psychological, and behavioral characteristics of children), family-level (e.g., caregiver demographics, parental support, and socioeconomic status), and environmental factors (e.g., availability of physical activity equipment) were assessed using self-reported scales (e.g., the Self-perception Profile for Children, the Physical Activity Enjoyment Scale, and the 12-item Psychological Well-Being Scale for Children) and objective measures (e.g., ActiGraph GT3X, the Chinese National Student Physical Fitness Standard, and the Test of Gross Motor Development-Third Edition). Multi-level regression models were employed using SPSS. RESULTS: The results demonstrated that children's age, sex, physical fitness, parental support, and the quality of home and community physical activity environments consistently influenced all three types of FMS, including locomotor, ball, and composite skills. Additionally, seven individual-level factors (children's age, sex, body mass index, light physical activity, sleep duration, perceived motor competence, and physical fitness) were associated with different types of FMS. CONCLUSIONS: The findings underscore the multidimensional and complex nature of FMS development, with individual-level factors playing a particularly significant role. Future research should adopt rigorous longitudinal designs, comprehensive assessment tools covering various FMS skills, and objective measurement of parents' movement behaviors to better understand the strength and direction of the relationship between socio-ecological factors and children's FMS.
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Ejercicio Físico , Destreza Motora , Humanos , Niño , Estudios Transversales , Aptitud Física , ChinaRESUMEN
Defect engineering has been regarded as an "all-in-one strategy" to alleviate the insufficient solar utilization in g-C3 N4 . However, without appropriate modification, the defect benefits will be partly offset due to the formation of deep localized defect states and deteriorated surface states, lowering the photocarrier separation efficiency. To this end, the defective g-C3 N4 is designed with both S dopants and N vacancies via a dual-solvent-assisted synthetic approach. The precise defect control is realized by the addition of ethylene glycol (EG) into precursor formation and molten sulfur into the pyrolysis process, which simultaneously induced g-C3N4. with shallow defect states. These shallow defect energy levels can act as a temporary electron reservoir, which are critical to evoke the migrated electrons from CB with a moderate trapping ability, thus suppressing the bulky photocarrier recombination. Additionally, the optimized surface states of DCN-ES are also demonstrated by the highest electron-trapping resistance (Rtrapping ) of 9.56 × 103 Ω cm2 and the slowest decay kinetics of surface carriers (0.057 s-1 ), which guaranteed the smooth surface charge transfer rather than being the recombination sites. As a result, DCN-ES exhibited a superior H2 evolution rate of 4219.9 µmol g-1 h-1 , which is 29.1-fold higher than unmodified g-C3 N4 .
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MXenes have been extensively studied due to their high metallic conductivity, hydrophilic properties, tunable layer structure and attractive surface chemistry, making them highly desirable for energy-related applications. However, slow catalytic reaction kinetics and limited active sites have severely impeded their further practical applications. Surface engineering of MXenes has been rationally designed and investigated to regulate their electronic structure, increase the density of active sites, optimize the binding energy, and thus boost the electrocatalytic performance. In this review, we comprehensively summarized the surface engineering strategies for MXene nanostructures, including surface termination engineering, defect engineering, heteroatom doping engineering (metals or non-metals), secondary material engineering, and extension to MXene analogues. By identifying the roles of each component in the engineered MXenes at the atomic level, their intrinsic active sites have been discussed to establish the relationships between the atomic structures and catalytic activities. We highlighted the state-of-the-art progress of MXenes in electrochemical conversion reactions including hydrogen, oxygen, carbon dioxide, nitrogen and sulfur conversion reactions. The challenges and perspectives of MXene-based catalysts for electrochemical conversion reactions are presented to inspire more efforts toward the understanding and development of MXene-based materials to meet the ever-growing demand for a sustainable future.
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Background: This study compares the impact of comprehensive care and conventional care on interventional therapy in children with congenital heart disease and to provide a reference basis for clinical care. Methods: Clinical randomized controlled trials (RCTs) examining care during interventional therapy in children with congenital heart disease were identified in the PubMed, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang databases using a combination of subject terms and free terms. The retrieval time was from the establishment of the database to November 27th, 2022. The control group was given conventional care and the experimental group was given comprehensive care on the basis of conventional care. The outcome indicators included one or more of postoperative complications (number of cases), puncture time (minutes), pain score (points), surgical operation time (minutes), X-ray exposure time (minutes) and length of hospital stay (days). Meta-analysis was performed using Stata 14.0 software. The publication bias test was conducted using Harbor's test. Results: A total of 24 RCTs were eventually included, and a total of 2,028 study subjects were enrolled, including 1,025 in the test group and 1,003 in the control group. Meta-analysis showed that comprehensive care resulted in a lower risk of complications [risk ratio (RR) =0.27; 95% confidence interval (CI): 0.21 to 0.34]. Furthermore, subjects who received comprehensive care had lower puncture time [standardized mean difference (SMD) =-2.50; 95% CI: -3.23 to -1.77], lower operating time [SMD (95% CI): -2.50 (-3.31, -1.68)], lower X-ray exposition time [SMD (95% CI): -1.29 (-2.51, -0.07)], shorter length of hospital stay [SMD (95% CI): -1.57 (-2.04, -1.09)], and lower pain scores [SMD (95% CI): -2.43 (-3.20, -1.65)]. Conclusions: Comprehensive care has higher clinical utility, which is worthy of clinical application and popularization.
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Background: Delirium is a common postoperative complication of acute type an aortic dissection, which is a serious threat to the patient's life after operation. However, there are many risk factors for delirium and there are different conclusions. The aim of this study was to systematically analyze the risk factors for postoperative delirium in patients with acute type a aortic dissection by means of meta-analysis. Methods: Literature related to the risk factors of postoperative delirium in patients with acute type A aortic dissection was searched via the China National Knowledge Infrastructure (CNKI), cqvip.com (VIP), WanFang, PubMed, Willey Library, Embase, and Web of Science databases. Two persons independently conducted literature screening, data extraction and literature quality evaluation according to the inclusion and exclusion criteria. The quality of literature was evaluated with Newcastle-Ottawa Scale (NOS). R 4.2.1 was used to compare the risk factors for meta-analysis. Results: After screening, 12 articles were included with a total of 2,511 cases, and 4 articles were at medium risk of bias and 8 articles were at low risk of bias. The meta-analysis results showed that patients in the delirium group had a higher probability of postoperative hypoxemia [odds ratio (OR) =1.65, 95% confidence interval (CI): 1.28-2.13, P<0.01], longer postoperative duration of ventilator assistance (OR =3.05, 95% CI: 2.47-3.77, P<0.01), higher incidence of renal insufficiency (OR =1.86, 95% CI: 1.33-2.58, P<0.01), lower hemoglobin levels (OR =0.33, 95% CI: 0.23-0.48, P<0.01), longer postoperative stay duration in the intensive care unit (ICU) (OR =2.25, 95% CI: 2.13-2.37, P<0.01), longer duration of hospitalization (OR =2.74, 95% CI: 2.37-3.16, P<0.01), and higher postoperative Acute Physiology and Chronic Health Evaluation II (APACHE II) scores (OR =1.01, 95% CI: 0.90-1.12, P=0.92). Conclusions: Post-op aortic dissection in patients with acute type A diabetes should be monitored for oxygen and blood levels. When patients had prolonged mechanical ventilation, renal insufficiency, decreased hemoglobin, and prolonged ICU stay, timely intervention is needed to prevent the high-risk factors of postoperative delirium.
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Two-dimensional (2D) nanofluidic membranes have shown great promise in harvesting osmotic energy from the salinity difference between seawater and fresh water. However, the output power densities are strongly hampered by insufficient membrane permselectivity. Herein, we demonstrate that vacancy engineering is an effective strategy to enhance the permselectivity of 2D nanofluidic membranes to achieve high-efficiency osmotic energy generation. Phosphorus vacancies were facilely created on NbOPO4 (NbP) nanosheets, which remarkably enlarged their negative surface charge. As verified by both experimental and theoretical investigations, the vacancy-introduced NbP (V-NbP) exhibited fast transmembrane ion migration and high ionic selectivity originating from the improved electrostatic affinity of cations. When applied in a natural river water|seawater osmotic power generator, the macroscopic-scale V-NbP membrane delivered a record-high power density of 10.7 W m-2, far exceeding the commercial benchmark of 5.0 W m-2. This work endows the remarkable potential of vacancy engineering for 2D materials in nanofluidic energy devices.
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Background: Transurethral split of the prostate (TUSP) is effective in treating benign prostatic hyperplasia (BPH). However, there is still a lack of research focusing on the optimal target population for TUSP. This study aimed to compare the efficacy of TUSP in patients with different prostate volumes or ages. Methods: The study was a multicenter retrospective study. The outcomes of TUSP in BPH patients with different prostate volumes or different ages were compared. A total of 439 patients were included in the study. Patients were divided into two groups according to prostate volume, with a cut-off value of 50 mL. Similarly, the cut-off value for the age groups was 70 years. Baseline patient characteristics and perioperative outcomes were recorded. Follow-up was performed at 1, 6, and 12 months after surgery. Results: The mean age of the patients was 73.4 years, and the mean prostate volume was 51.2 mL. At 12-month follow-up after TUSP treatment, the patients' International Prostate Symptom Scores (IPSS), quality of life (QoL) scores, and postvoid residual (PVR) volumes decreased significantly, while peak urinary flow rate (Qmax) increased significantly. Intraoperative hemoglobin (Hb) reduction was significantly lower in the small volume group than in the large volume group. The incidence of postoperative urinary urgency and transient incontinence was lower in the small volume group. IPSS score, PVR, and Qmax in the small volume group showed more remarkable changes at several time points compared to the preoperative period. Postoperative pain scores were higher in the small volume group than in the large volume group. There were no differences between the two groups in terms of long-term complications. The younger group showed greater variation in PVR and Qmax at some time points but less variation in QoL than the older group. Conclusions: TUSP is overall safe and effective in treating BPH. This study showed differences in the outcomes of TUSP in treating different prostate volumes or ages of BPH patients. The optimal surgical approach for BPH patients might be selected clinically based on a combination of prostate volume or patient age.
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BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) prior to surgery is the standard treatment for patients with locally advanced rectal cancer (LARC), while parts of them show poor therapeutic response accompanied by therapy adverse effects. Predictive biomarkers for nCRT response could facilitate the guidance on treatment decisions but are still insufficient until now, which limits the clinical applications of nCRT in LARC patients. METHODS: In our study, 37 formalin-fixed paraffin-embedded tumor biopsies were obtained from patients with LARC before receiving 5-fluorouracil based nCRT. Proteomics analyses were conducted to identify the differentially expressed proteins (DEPs) between total responders (TR) and poor responders (PR). The DEPs were validated via ROC plotter web tool and their predictive performance was evaluated by receiver operating characteristic analysis. Functional enrichment analyses were performed to further explore the potential mechanisms underlying nCRT response. RESULTS: Among 3,998 total proteins, 91 DEPs between TR and PR were screened out. HSPA4, NIPSNAP1, and SPTB all with areas under the curve (AUC) ~ 0.8 in the internal discovery cohort were independently validated by the external mRNA datasets (AUC ~ 0.7), and their protein levels were linearly correlated with the graded responses to nCRT in the internal cohort. The combination of HSPA4 and SPTB could distinctly discriminate the TR and PR groups (AUC = 0.980, p < 0.0001). Moreover, multiple combinations of the three proteins realized increased specificity and/or sensitivity, while achieving favorable predictive value when moderate responders were introduced into the ROC analysis. Pathways including DNA damage repair, cell cycle, and epithelial mesenchymal transition were involved in nCRT response according to the enrichment analysis results. CONCLUSIONS: HSPA4, SPTB and NIPSNAP1 in tumor biopsies and/or their optional combinations might be potential predictive markers for nCRT response in patients with LARC. The DEPs and their related functions have implications for the potential mechanisms of treatment response to nCRT in patients with LARC.
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Rationally electronic structure engineering of nanocomposite electrodes shows great promise for enhancing the electrochemical performance of rechargeable batteries. Herein, we report antimony single atoms and quantum dots (â¼5 nm) codecorated Ti3C2Tx MXene-based aerogels (Sb SQ@MA) for high-performance potassium-ion batteries (PIBs). We found that the atomically dispersed Sb could modify the electronic structure of the Sb/Ti3C2Tx composite, improve the charge transfer kinetics, and enhance the potassium storage capability at the heterointerfaces. Additionally, the MXene-based aerogel with rich surface functional groups and defects provides abundant anchoring sites and endows the composite reinforced structural stability and highly efficient electron transfer. The high loading of Sb (â¼60.3 wt %) with short ionic transport pathways is desired potassium reservoirs. These features synergistically enhance the rate and cycling performance of the Sb SQ@MA electrodes in PIBs. This work has demonstrated an enlightening technique to tailor the interface activity of heterostructured electrodes for electrochemical applications.
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The advancement of lithium-oxygen (Li-O2) batteries has been hindered by challenges including low discharge capacity, poor energy efficiency, severe parasitic reactions, etc. We report an Li-O2 battery operated via a new quenching/mediating mechanism that relies on the direct chemical reactions between a versatile molecule and superoxide radical/Li2O2. The battery exhibits a 46-fold increase in discharge capacity, a low charge overpotential of 0.7 V, and an ultralong cycle life >1400 cycles. Featuring redox-active 2,2,6,6-tetramethyl-1-piperidinyloxy moieties bridged by a quenching-active perylene diimide backbone, the tailor-designed molecule acts as a redox mediator to catalyze discharge/charge reactions and serves as a reusable superoxide quencher to chemically react with superoxide species generated during battery operation. The all-in-one molecule can simultaneously tackle issues of parasitic reactions associated with superoxide radicals, singlet oxygen, high overpotentials, and lithium corrosion. The molecular design of multifunctional additives combining various capabilities opens a new avenue for developing high-performance Li-O2 batteries.
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Gasdermin E (GSDME) is one of the main members of the GSDM family and is originally involved in hereditary hearing loss. Recent studies have reported that GSDME expression is epigenetically silenced by methylation in several common tumours, thereby enhancing tumour proliferation and metastasis. GSDME is also downregulated in cancer tissues compared with normal tissues, which suggests that GSDME can be considered a tumour suppressor. Furthermore, GSDME is the effector protein of caspase-3 and granzyme B in pyroptosis, and it plays a significant role in innate immunity, tissue damage, cancer, and hearing loss, thus revealing potential novel therapeutic avenues. A great deal of evidence reveals that GSDME can be implemented as a biomarker in cancer diagnosis and monitoring, chemotherapy, immunotherapy, and chemoresistance. Based on the current knowledge of GSDME, this review is focussed on its mechanism of action and the most recent advances in its role in cancer and normal physiology.
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Neoplasias , Piroptosis , Humanos , Neoplasias/genética , Neoplasias/terapiaRESUMEN
BACKGROUND: E2Fs are important components of transcription factors and play key roles in occurrence or advancement of various cancers, but the expression and exact roles of each E2F in colorectal cancer (CRC) are rarely known. METHODS: To address this issue, we investigated the roles and prognostic values of E2Fs expressions in CRC patients by searching ONCOMINE, cBioPortal, GEPIA, Matascape and UALCAN. RESULTS: E2F1, 3-8 were upregulated at the mRNA level and E2F2 was less expressed in CRC tissues than in normal tissues. The eight E2Fs were correlated with tumor stages of CRC. Survival analysis using GEPIA revealed that high expressions of E2F3, 4 were related with short overall survival in all CRC patients. The mutation rate of E2Fs (60%) was high and genetic alteration in E2Fs was linked with longer overall survival in CRC patients. Functional analysis implied that E2Fs and their 50 nearby genes were concentrated in tumor-related pathways. CONCLUSIONS: E2Fs may be candidate biomarkers for CRC diagnosis and E2F3, 4 are potential prognosis biomarkers of CRC. Nevertheless, our findings must be validated in the future to popularize the clinical application of E2Fs in CRC.
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Neoplasias Colorrectales , Factores de Transcripción E2F/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Humanos , Pronóstico , ARN MensajeroRESUMEN
Accumulating evidence shows that elevated levels of reactive oxygen species (ROS) are associated with cancer initiation, growth, and response to therapies. As concentrations increase, ROS influence cancer development in a paradoxical way, either triggering tumorigenesis and supporting the proliferation of cancer cells at moderate levels of ROS or causing cancer cell death at high levels of ROS. Thus, ROS can be considered an attractive target for therapy of cancer and two apparently contradictory but virtually complementary therapeutic strategies for the regulation of ROS to treat cancer. Despite tremendous resources being invested in prevention and treatment for cancer, cancer remains a leading cause of human deaths and brings a heavy burden to humans worldwide. Chemotherapy remains the key treatment for cancer therapy, but it produces harmful side effects. Meanwhile, the process of de novo development of new anticancer drugs generally needs increasing cost, long development cycle, and high risk of failure. The use of ROS-based repurposed drugs may be one of the promising ways to overcome current cancer treatment challenges. In this review, we briefly introduce the source and regulation of ROS and then focus on the status of repurposed drugs based on ROS regulation for cancer therapy and propose the challenges and direction of ROS-mediated cancer treatment.
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Antineoplásicos/uso terapéutico , Reposicionamiento de Medicamentos , Neoplasias/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Proteínas del Complejo de Cadena de Transporte de Electrón/metabolismo , Glutatión/metabolismo , Humanos , Factor 2 Relacionado con NF-E2/metabolismoRESUMEN
The regulation of anions and cations at the atomic scale is of great significance in membrane-based separation technologies. Ionic transport regulation techniques could also play a crucial role in developing high-performance alkali metal batteries such as alkali metal-sulfur and alkali metal-selenium batteries, which suffer from the non-uniform transport of alkali metal ions (e.g., Li+ or Na+) and detrimental shuttling effect of polysulfide/polyselenide anions. These drawbacks could cause unfavourable growth of alkali metal depositions at the metal electrode and irreversible consumption of cathode active materials, leading to capacity decay and short cycling life. Herein, we propose the use of a polypropylene separator coated with negatively charged Ti0.87O2 nanosheets with Ti atomic vacancies to tackle these issues. In particular, we demonstrate that the electrostatic interactions between the negatively charged Ti0.87O2 nanosheets and polysulfide/polyselenide anions reduce the shuttling effect. Moreover, the Ti0.87O2-coated separator regulates the migration of alkali ions ensuring a homogeneous ion flux and the Ti vacancies, acting as sub-nanometric pores, promote fast alkali-ion diffusion.
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Rechargeable multivalent metal (e.g., Ca, Mg or, Al) batteries are ideal candidates for large-scale electrochemical energy storage due to their intrinsic low cost. However, their practical application is hampered by the low electrochemical reversibility, dendrite growth at the metal anodes, sluggish multivalent-ion kinetics in metal oxide cathodes and, poor electrode compatibility with non-aqueous organic-based electrolytes. To circumvent these issues, here we report various aqueous multivalent-ion batteries comprising of concentrated aqueous gel electrolytes, sulfur-containing anodes and, high-voltage metal oxide cathodes as alternative systems to the non-aqueous multivalent metal batteries. This rationally designed aqueous battery chemistry enables satisfactory specific energy, favorable reversibility and improved safety. As a demonstration model, we report a room-temperature calcium-ion/sulfur| |metal oxide full cell with a specific energy of 110 Wh kg-1 and remarkable cycling stability. Molecular dynamics modeling and experimental investigations reveal that the side reactions could be significantly restrained through the suppressed water activity and formation of a protective inorganic solid electrolyte interphase. The unique redox chemistry of the multivalent-ion system is also demonstrated for aqueous magnesium-ion/sulfur||metal oxide and aluminum-ion/sulfur||metal oxide full cells.
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Identification of active sites for highly efficient catalysts at the atomic scale for water splitting is still a great challenge. Herein, we fabricate ultrathin nickel-incorporated cobalt phosphide porous nanosheets (Ni-CoP) featuring an atomic heterometallic site (NiCo16-xP6) via a boron-assisted method. The presence of boron induces a release-and-oxidation mechanism, resulting in the gradual exfoliation of hydroxide nanosheets. After a subsequent phosphorization process, the resultant Ni-CoP nanosheets are implanted with unsaturated atomic heterometallic NiCo16-xP6 sites (with Co vacancies) for alkaline hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The optimized Ni-CoP exhibits a low overpotential of 88 and 290 mV at 10 mA cm-2 for alkaline HER and OER, respectively. This can be attributed to reduced free energy barriers, owing to the direct influence of center Ni atoms to the adjacent Co/P atoms in NiCo16-xP6 sites. These provide fundamental insights on the correlation between atomic structures and catalytic activity.