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Transition metal silicates (TMSs) are attempted for the electrocatalyst of oxygen evolution reaction (OER) due to their special layered structure in recent years. However, defects such as low theoretical activity and conductivity limit their application. Researchers always prefer to composite TMSs with other functional materials to make up for their deficiency, but rarely focus on the effect of intrinsic structure adjustment on their catalytic activity, especially anion structure regulation. Herein, applying the method of interference hydrolysis and vacancy reserve, new silicate vacancies (anionic regulation) are introduced in cobalt silicate hydroxide (CoSi), named SV-CoSi, to enlarge the number and enhance the activity of catalytic sites. The overpotential of SV-CoSi declines to 301 mV at 10 mA cm-2 compared to 438 mV of CoSi. Source of such improvement is verified to be not only the increase of active sites, but also the positive effect on the intrinsic activity due to the enhancement of cobalt-oxygen covalence with the variation of anion structure by density functional theory (DFT) method. This work demonstrates that the feasible intrinsic anion structure regulation can improve OER performance of TMSs and provides an effective idea for the development of non-noble metal catalyst for OER.
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PURPOSE: We aimed at assessing the predictive ability of ultrasound-based radiomics combined with clinical characteristics for axillary lymph node (ALN) status in early-stage breast cancer patients and to compare performance in different peritumoral regions. MATERIALS AND METHODS: A total of 755 patients (527 in the primary cohort and 228 in the external validation cohort) were enrolled in this study. Ultrasound images for all patients were acquired and radiomics analysis performed for intratumoral and different peritumoral regions. The MRMR and LASSO regression analyses were performed on extracted features from the primary cohort to construct a radiomics signature formula combined with clinical characteristics. Pearson's coefficient and the variance inflation factor (VIF) were performed to check the correlation and the multicollinearity among the final predictors. The best performing model was selected to develop a nomogram, which was established by performing binary logistic regression and acquiring cut-off values based on the corresponding nomogram scores of the masses. RESULTS: Among all the radiomics models, the "Mass + Margin3mm" model exhibited the best performance. The areas under the curves (AUC) of the nomogram in the primary and external validation cohorts were 0.906 (95% confidence intervals [CI] 0.882-0.930) and 0.922 (95% CI 0.894-0.960), respectively. They both showed good calibrations. The nomogram exhibited a good ability to discriminate between positive and negative lymph nodes (AUC: 0.853 (95% CI 0.816-0.889) in primary cohort, 0.870 (95% CI 0.818-0.922) in validation cohort), and between low-volume and high-volume lymph nodes (AUC: 0.832 (95% CI 0.781-0.884) in primary cohort, 0.911 (95% CI 0.858-0.964) in validation cohort). CONCLUSIONS: The established nomogram is a prospective clinical prediction tool for non-invasive assessment of ALN status. It has the ability to enhance the accuracy of early-stage breast cancer treatment.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Nomogramas , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/patología , Estudios Prospectivos , Radiómica , Estudios Retrospectivos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patologíaRESUMEN
The development of electrode materials for supercapacitors (SCs) is greatly desired, and this still poses an immense challenge for researchers. Cobalt silicate (Co2SiO4, denoted as CoSi) with a high theoretical capacity is deemed to be one of the sustainable electrode materials for SCs. However, its achieved electrochemical properties are still not satisfying. Herein, the phosphorus (P)-doped cobalt silicate, denoted as PCoSi, is synthesized by a calcining strategy. The PCoSi exhibits 1D nanobelts with a specific surface area of 46 m2âg-1, and it can significantly improve the electrochemical properties of CoSi. As a supercapacitor's (SC's) electrode, the specific capacitance of PCoSi attains 434 Fâg-1 at 0.5 Aâg-1, which is much higher than the value of CoSi (244 Fâg-1 at 0.5 Aâg-1). The synergy between the composition and structure endows PCoSi with attractive electrochemical properties. This work provides a novel strategy to improve the electrochemical performances of transition metal silicates.
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BACKGROUND: Pancreatic cancer is one of the most lethal malignancies and has an extremely poor diagnosis and prognosis. The development of resistance to gemcitabine is still a major challenge. The long noncoding RNA PVT1 was reported to be involved in carcinogenesis and chemoresistance; however, the mechanism by which PVT1 regulates the sensitivity of pancreatic cancer to gemcitabine remains poorly understood. METHODS: The viability of pancreatic cancer cells was assessed by MTT assay in vitro and xenograft tumor formation assay in vivo. The expression levels of PVT1 and miR-619-5p were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Western blotting analysis and qRT-PCR were performed to assess the protein and mRNA levels of Pygo2 and ATG14, respectively. Autophagy was explored via autophagic flux detection under confocal microscopy and autophagic vacuole investigation under transmission electron microscopy (TEM). The functional role and mechanism of PVT1 were further investigated by gain- and loss-of-function assays in vitro. RESULTS: In the present study, we demonstrated that PVT1 was up-regulated in gemcitabine-resistant pancreatic cancer cell lines. Gain- and loss-of-function assays revealed that PVT1 impaired sensitivity to gemcitabine in vitro and in vivo. We further found that PVT1 up-regulated the expression of both Pygo2 and ATG14 and thus regulated Wnt/ß-catenin signaling and autophagic activity to overcome gemcitabine resistance through sponging miR-619-5p. Moreover, we discovered three TCF/LEF binding elements (TBEs) in the promoter region of PVT1, and activation of Wnt/ß-catenin signaling mediated by the up-regulation of Pygo2 increased PVT1 expression by direct binding to the TBE region. Furthermore, PVT1 was discovered to interact with ATG14, thus promoting assembly of the autophagy specific complex I (PtdIns3K-C1) and ATG14-dependent class III PtdIns3K activity. CONCLUSIONS: These data indicate that PVT1 plays a critical role in the sensitivity of pancreatic cancer to gemcitabine and highlight its potential as a valuable target for pancreatic cancer therapy.
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Proteínas Adaptadoras del Transporte Vesicular/genética , Proteínas Relacionadas con la Autofagia/genética , Autofagia/genética , Resistencia a Antineoplásicos/genética , Péptidos y Proteínas de Señalización Intracelular/genética , MicroARNs/genética , Neoplasias Pancreáticas/genética , ARN Largo no Codificante/genética , Vía de Señalización Wnt , Animales , Sitios de Unión , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Unión Proteica , Interferencia de ARN , Ensayos Antitumor por Modelo de Xenoinjerto , GemcitabinaRESUMEN
In the wake of the carbon-neutral era, the exploration of innovative materials for energy storage and conversion has garnered increasing attention. While nickel silicates have been a focal point in energy storage research, their application in supercapacitors (SCs) has been relatively underreported due to poor conductivity. A newly designed architecture, designated as rGO@NiSiO@NiO/C (abbreviated for reduced graphene oxide (rGO), nickel silicate (NiSiO), nickel oxide/carbon (NiO/C)), has been developed to enhance the electrochemical performance of NiSiO. The incorporation of inner rGO provides structural support for NiSiO, enhancing conductivity, while the outer NiO/C layer not only boosts conductivity but also safeguards NiSiO from structural degradation and electrolyte dissolution. This architecture eliminates multi-phase mixtures, facilitating rapid electron/mass transfer kinetics and accelerating electrochemical reactions, resulting in exceptional electrochemical properties. The rGO@NiSiO@NiO/C architecture achieves a specific capacitance of 324F·g-1 at 0.5 A·g-1, with a superb cycle performance of â¼ 91 % after 10,000 cycles, surpassing state-of-the-art nickel silicates. Furthermore, the hybrid supercapacitor (HSC) device incorporating the rGO@NiSiO@NiO/C electrode attains an areal capacitance of 159 mF·cm-2 at 2.5 mA·cm-2, a retention ratio of â¼ 98 % after 10,000 cycles, and an energy density of 0.68 Wh·m-2 (26.7 Wh·kg-1) at 3.4 W·m-2 (343.8 W·kg-1). This study presents a layer-by-layer approach for constructing transition metal silicates/C architectures to enhance their electrochemical performance.
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OBJECTIVES: To build a predictive model for central lymph node metastasis (CLNM) in unifocal papillary thyroid carcinoma (UPTC) using a combination of clinical features and multimodal ultrasound (MUS). METHODS: This retrospective study, included 390 UPTC patients who underwent MUS between January 2017 and October 2022 and were divided into a training cohort (n = 300) and a validation cohort (n = 90) based on a cut-off date of June 2022. Independent indicators for constructing the predictive nomogram models were identified using multivariate regression analysis. The diagnostic yield of the 3 predictive models was also assessed using the area under the receiver operating characteristic curve (AUC). RESULTS: Both clinical factors (age, diameter) and MUS findings (microcalcification, virtual touch imaging score, maximal value of virtual touch tissue imaging and quantification) were significantly associated with the presence of CLNM in the training cohort (all P < .05). A predictive model (MUS + Clin), incorporating both clinical and MUS characteristics, demonstrated favourable diagnostic accuracy in both the training cohort (AUC = 0.80) and the validation cohort (AUC = 0.77). The MUS + Clin model exhibited superior predictive performance in terms of AUCs over the other models (training cohort 0.80 vs 0.72, validation cohort 0.77 vs 0.65, P < .01). In the validation cohort, the MUS + Clin model exhibited higher sensitivity compared to the CLNM model for ultrasound diagnosis (81.2% vs 21.6%, P < .001), while maintaining comparable specificity to the Clin model alone (62.3% vs 47.2%, P = .06). The MUS + Clin model demonstrated good calibration and clinical utility across both cohorts. CONCLUSION: Our nomogram combining non-invasive features, including MUS and clinical characteristics, could be a reliable preoperative tool to predict CLNM treatment of UPTC. ADVANCES IN KNOWLEDGE: Our study established a nomogram based on MUS and clinical features for predicting CLNM in UPTC, facilitating informed preoperative clinical management and diagnosis.
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Nomogramas , Neoplasias de la Tiroides , Humanos , Metástasis Linfática , Estudios Retrospectivos , Cáncer Papilar TiroideoRESUMEN
Among battery technologies, aqueous zinc ion batteries (AZIBs) have hit between the eyes in the next generation of extensive energy storage devices due to their outstanding superiority. The main problem that currently restricts the development of AZIBs is how to obtain stable Zn anodes. In this study, taking the improvement of a series of problems caused by the physically attached artificial interfacial layer on Zn anode as a starting point, a nanosheet morphology of ZnSiO3 (denoted as ZnSi) is constructed by self-growth on Zn foil (Zn@ZnSi) by a simple hydrothermal reaction. The ZnSi nano-interfacial layer effectively slices the surface of the Zn foil into individual microscopic interfacial layers, constructing abundant pores. The nanosheets of Zn@ZnSi construct rich nanoscale Zn2+ transport channels, which provide higher electron and ion transport paths, thus achieving the effect of effectively homogenizing the electric field distribution and decreasing the local current density. Thanks to its inherent and structural properties, the Zn@ZnSi anode has a high specific capacity and good cycling stability compared with the Zn electrode. The lifetime of the Zn@ZnSi//Zn@ZnSi symmetric cell is much higher than that of the Zn//Zn symmetric cell at 1 mA cm-2. The capacity of the Zn@ZnSi//NH4V4O10 full cell can still reach 98 mAh g-1 after 1000 cycles at 1 A/g. The low-cost and scalable synthesis of ZnSi nano-interfacial layer on Zn is expected to provide new perspectives on interfacial engineering for Zn anodic protection.
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Over the past few years, the flexible quasi-solid-state zinc-ion hybrid supercapacitors (FQSS ZHSCs) have been found to be ideal for wearable electronics applications due to their high areal capacitance and energy density. The assembly of desirable ZHSCs devices that have promising practical applications is of high importance, whereas it is still challenging to assemble ZHSCs devices. In this study, a ZHSC that exhibited ultrahigh areal capacitance and high stability was developed by using an active carbon cloth (ACC) cathode, which could improve ionic adsorption. The as-obtained ACC cathode had an energy storage mechanism due to the electrical double-layer capacitive behavior of Zn2+, which was accompanied by the dissolution/deposition of Zn4SO4(OH)6·5H2O. The ACC//Zn@ACC ZHSC device exhibited an areal capacitance of 2437 mF cm-2 (81 F cm-3, 203 F g-1 under the mass of ACC with â¼12 mg cm-2) at 1 mA cm-2, an areal energy density of 1.354 mWh cm-2 at 1 mW cm-2, as well as high stability (with an insignificant capacitance decline after 20000 cycles), which was demonstrated to outperform the existing ZHSCs. Furthermore, the assembled flexible device still had competitive capacitance, energy density and service life when integrated into a FQSS ZHSC. When applied in practice, the device could achieve high mechanical flexibility, wearable stability and output. This study can inspire the development of the FQSS ZHSC device to satisfy the demands for wearable energy storage devices with high performance.
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Oxygen Evolution Reaction (OER) has gained significant attention due to its crucial role in renewable energy systems. The quest for efficient and low-cost OER catalysts remains a challenge of significant interest and importance. In this work, phosphate-incorporated cobalt silicate hydroxide (denoted as CoSi-P) is reported as a potential electrocatalyst for OER. The researchers first synthesized hollow spheres of cobalt silicate hydroxide Co3(Si2O5)2(OH)2 (denoted as CoSi) using SiO2 spheres as a template through a facile hydrothermal method. Phosphate (PO43-) was then introduced to layered CoSi, leading to the reconstruction of the hollow spheres into sheet-like architectures. As expected, the resulting CoSi-P electrocatalyst demonstrated low overpotential (309 mV at 10 mA·cm-2), large electrochemical active surface area (ECSA), and low Tafel slope. These parameters outperform CoSi hollow spheres and cobaltous phosphate (denoted as CoPO). Moreover, the catalytic performance achieved at 10 mA cm-2 is comparable or even better than that of most transition metal silicates/oxides/hydroxides. The findings indicate that the incorporation of phosphate into the structure of CoSi can enhance its OER performance. This study not only provides a non-noble metal catalyst CoSi-P but also demonstrates that the incorporation of phosphates into transition metal silicates (TMSs) offers a promising strategy for the design of robust, high-efficiency, and low-cost OER catalysts.
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OBJECTIVE: This study aims to analyze the performance of endorectal ultrasound (ERUS) combined with shear wave elastography (SWE) for rectal tumor staging. METHODS: Forty patients with rectal tumors who had surgery were enrolled. They underwent ERUS and SWE examinations before surgery. Pathological results were used as the gold standard for tumor staging. The stiffness values of the rectal tumor, peritumoral fat, distal normal intestinal wall, and distal perirectal fat were analyzed. The diagnostic accuracy of ERUS stage, tumor SWE stage, ERUS combined with tumor SWE stage, and ERUS combined with peritumoral fat SWE stage were compared and evaluated by receiver operating characteristic (ROC) curve to select the best staging index. RESULTS: From T1 to T3 stage, the maximum elasticity (Emax) of the rectal tumor increased gradually (pâ<â0.05). The cut-off values of adenoma/T1 and T2, T2 and T3 tumors were 36.75 and 85.15kPa, respectively. The diagnostic coincidence rate of tumor SWE stage was higher than that of ERUS stage. Overall diagnostic accuracy of ERUS combined with peritumoral fat SWE Emax restaging was significantly higher than that of ERUS. CONCLUSIONS: ERUS combined with peritumoral fat SWE Emax for tumor restaging can effectively distinguish between stage T2 and T3 rectal tumors, which provides an effective imaging basis for clinical decisions.
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Adenoma , Diagnóstico por Imagen de Elasticidad , Neoplasias del Recto , Humanos , Diagnóstico por Imagen de Elasticidad/métodos , Ultrasonografía , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Estadificación de Neoplasias , Adenoma/patologíaRESUMEN
Abnormal activation of Wnt/ß-catenin-mediated transcription is closely associated with the malignancy of pancreatic cancer. Family with sequence similarity 83 member A (FAM83A) was shown recently to have oncogenic effects in a variety of cancer types, but the biological roles and molecular mechanisms of FAM83A in pancreatic cancer need further investigation. Here, we newly discovered that FAM83A binds directly to ß-catenin and inhibits the assembly of the cytoplasmic destruction complex thus inhibiting the subsequent phosphorylation and degradation. FAM83A is mainly phosphorylated by the SRC non-receptor kinase family member BLK (B-lymphoid tyrosine kinase) at tyrosine 138 residue within the DUF1669 domain that mediates the FAM83A-ß-catenin interaction. Moreover, FAM83A tyrosine 138 phosphorylation enhances oncogenic Wnt/ß-catenin-mediated transcription through promoting ß-catenin-TCF4 interaction and showed an elevated nucleus translocation, which inhibits the recruitment of histone deacetylases by TCF4. We also showed that FAM83A is a direct downstream target of Wnt/ß-catenin signaling and correlates with the levels of Wnt target genes in human clinical pancreatic cancer tissues. Notably, the inhibitory peptides that target the FAM83A-ß-catenin interaction significantly suppressed pancreatic cancer growth and metastasis in vitro and in vivo. Our results revealed that blocking the FAM83A cascade signaling defines a therapeutic target in human pancreatic cancer.
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Proteínas de Neoplasias , Neoplasias Pancreáticas , beta Catenina , Familia-src Quinasas , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Carcinogénesis/genética , Transformación Celular Neoplásica/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/genética , Fosforilación/genética , Tirosina/metabolismo , Vía de Señalización Wnt/genética , Familia-src Quinasas/genética , Familia-src Quinasas/metabolismo , Neoplasias PancreáticasRESUMEN
Autophagy serves as a pro-survival mechanism for a cell or a whole organism to cope with nutrient stress. Our understanding of the molecular regulation of this fusion event remains incomplete. Here, we identified RUNDC1 as a novel ATG14-interacting protein, which is highly conserved across vertebrates, including zebrafish and humans. By gain and loss of function studies, we demonstrate that RUNDC1 negatively modulates autophagy by blocking fusion between autophagosomes and lysosomes via inhibiting the assembly of the STX17-SNAP29-VAMP8 complex both in human cells and the zebrafish model. Moreover, RUNDC1 clasps the ATG14-STX17-SNAP29 complex via stimulating ATG14 homo-oligomerization to inhibit ATG14 dissociation. This also prevents VAMP8 from binding to STX17-SNAP29. We further identified that phosphorylation of RUNDC1 Ser379 is crucial to inhibit the assembly of the STX17-SNAP29-VAMP8 complex via promoting ATG14 homo-oligomerization. In line with our findings, RunDC1 is crucial for zebrafish in their response to nutrient-deficient conditions. Taken together, our findings demonstrate that RUNDC1 is a negative regulator of autophagy that restricts autophagosome fusion with lysosomes by clasping the ATG14-STX17-SNAP29 complex to hinder VAMP8 binding.
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Oxygen evolution reaction (OER) has drawn ever-increasing attention because of its essential role in various renewable-energy technologies. In spite of tremendous research efforts, developing high-performance OER catalysts at low cost remains a great challenge. Inspired by two earth-abundant elements Fe and Si, herein, we report a Fe-Co2SiO4 composite consisting of well dispersed iron oxide (FeOx) decorated Co2SiO4 hollow nanospheres as an economical and promising OER catalyst. Although Co2SiO4 or FeOx alone has little OER activity, their composite exhibits satisfied performance, that is highly related to geometric effect and bimetal component electronic interactions. The Fe-Co2SiO4 composite exhibits comparable catalytic activity to most of transition mental oxide/hydroxide relevant composites at 10 mA cm-2. It is even 1.6 times higher than commercial RuO2 electrocatalyst at high current density 100 mA cm-2 in alkaline solution. In this work, surface decoration of transition metal silicate provides a new horizon to design high-performance and economical OER catalysts.
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Aqueous rechargeable Zn-ion batteries (ARZIBs) have been attracting a great deal of attention due to their immense potential in large-scale power grid applications. It is of great significance to explore cathode material with novel designed structure and first-class performances for ARZIBs. Herein, we successfully construct a double-sandwich-like structure, MOF-derived carbon/manganese silicate/reduced graphene oxide/manganese silicate/MOF-derived carbon (denoted as rGO/MnSi/MOF-C), as the cathode material for ARZIBs. Among the double-sandwich-like structure, manganese silicate (Mn2SiO4, denoted as MnSi) is in the middle of internal reduced graphene oxide (rGO) and external MOF-8 derived carbon (MOF-C). This integrated rGO/MnSi/MOF-C with double-sandwich-like structure can not only avert the sluggish electronic conduction progress caused by the conventional three-phase mixture system of rGO, MnSi and MOF-C, but also display promising Zn2+ storing capability. As expected, in mild aqueous 2 M (mol L-1) ZnSO4 + 0.2 M MnSO4 electrolyte, the initial discharge capacity of rGO/MnSi/MOF-C cathode reaches to 246 mAh·g-1, and the peak discharge capacity reaches to 462 mAh·g-1 at 0.1 A·g-1. This work not only involves the novel MnSi-based cathode for ARZIBs, but also first demonstrates our assumption of constructing the double-sandwich-like structure to improve Zn2+ storage. Moreover, the concept "double-sandwich-like structure" provides an idea for synthesizing the integrated carbon/transition metal silicates (TMSs)/carbon structure to boost the electrochemical properties of TMSs for energy-storing devices.
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Cobalt silicate (CoSi) is a promising electrode material for supercapacitors (SCs) and an electrocatalytic material for the oxygen evolution reaction (OER). How to synthesize cobalt silicate with excellent energy storage and OER properties has not been reported and it is a great challenge for researchers to accomplish it. In this work, we find that the electrochemical properties of CoSi are particularly affected by critical factors during the synthesis process. Three types of CoSi compounds are synthesized using Stöber SiO2 as the self-sacrificing template via a hydrothermal reaction. The CoSi compounds generated from different reaction systems have obvious differences in the macrostate, microscopic morphology, composition and valence, leading to different electrochemical performances for energy storage and OER properties. The findings reveal that the differences (especially valence) among CoSi are determined by the formation of the metal source in the reaction system. The specific capacitance of CoSi-3 obtained from the system with basic salts as the metal source is eight times higher than that of CoSi-1 obtained from the system with coordination compounds as the metal source, whereas CoSi-1 has a greater advantage in electrocatalytic activity. This work provides insight for the synthesis of cobalt silicates applied to energy storage and conversion.
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Epidermal growth factor receptor (EGFR) plays critical roles in cell proliferation and tumorigenesis. Autophagy has emerged as a potential mechanism involved in the acquired resistance to anti-EGFR treatments, however, the molecular mechanisms has not been fully addressed. In this study, we identified EGFR interacts with STYK1, a positive autophagy regulator, in EGFR kinase activity dependent manner. We found that EGFR phosphorylates STYK1 at Y356 site and STYK1 inhibits activated EGFR mediated Beclin1 tyrosine phosphorylation and interaction between Bcl2 and Beclin1, thus enhances PtdIns3K-C1 complex assembly and autophagy initiation. We also demonstrated that STYK1 depletion increased the sensitivity of NSCLC cells to EGFR-TKIs in vitro and in vivo. Moreover, EGFR-TKIs induced activation of AMPK phosphorylates STYK1 at S304 site. STYK1 S304 collaborated with Y356 phosphorylation to enhance the EGFR-STYK1 interaction and reverse the inhibitory effects of EGFR to autophagy flux. Collectively, these data revealed new roles and cross-talk between STYK1 and EGFR in autophagy regulation and EGFR-TKIs sensitivity in NSCLC.
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The design and preparation of electrode materials with excellent performance is particularly important due to the current global scarcity of energy supplies, especially those using sustainable and renewable materials. In this work, it is first proposed to apply iron silicate (FeSi), which is synthesized using environmentally friendly biomass as a raw material, as an electrode material for supercapacitors (SCs). FeSi is derived from the calcination of reed leaves (RLs) in combination with a hydrothermal method, and spherical FeSi retains the porosity of the RL precursors and shows remarkable electrochemical performance. The specific capacitance of FeSi as a SC electrode can reach 575 F g-1 at 0.5 A g-1 in the voltage window from -1 to -0.5 V. Simultaneously, the FeSi electrode exhibits favorable cycling stability with 76% capacitance retention after 10 000 cycles and outstanding electrical conductivity. This finding provides a novel method of preparing a kind of untapped electrode material, porous FeSi nanoparticles derived from RLs, and the resulting FeSi material shows enormous potential for energy storage via high-performance SCs.
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Vanadium oxides attract much attention and are concerned as one of the most promising cathodes for aqueous zinc-ion batteries (AZIBs) owing to the layered structures. However, their intensive development is limited by the fragile structures and laggard ion-transferring. Herein, Mn2+ inserted hydrated vanadium pentoxide nanobelts/reduced graphene oxide (MnxV2O5·nH2O/rGO, abbreviated as MnVOH/rGO) was prepared by a simple one-pot hydrothermal process, delivering excellent electrochemical properties for AZIBs. The Zn//MnVOH/rGO cell operates well even at changing current densities over 45 cycles, behaving 361 mAh·g-1 at 0.1 A·g-1, 323 mAh·g-1 as the current density gradually increasing to 2 A·g-1 and 350 mAh·g-1 when gradually back to 0.1 A·g-1 (â¼97% of initial capacity). Such a superb cycling and rate performance is ascribed to the unique stable structure with the compact electrostatic attraction between Mn2+ and V2O5·nH2O (VOH) laminate. On the one hand, Mn2+ generates electrostatic network with [VO6] polyhedrons and suppresses the following electrostatic trap for the moving Zn2+. On the other hand, rGO improves the conductivity, endowing the high capacity and energy density. The performance of the MnVOH/rGO cathode exceeds most of vanadium-based cathodes applying in AZIBs and paves the way to the ideal energy storage system.
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Recently, solid-state aqueous Zn-ion batteries (ZIBs) have become the most promising wearable storage systems to replace Li-ion batteries owing to their advantages such as high safety and environmental friendliness. However, the critical challenge is to develop stable and robust cathode materials for excellent Zn2+ storage. In this study, a hydrated vanadium pentoxide/reduced graphene oxide-polyvinyl alcohol (V2O5â nH2O/rGO-PVA, abbreviated as VOH/rGO-P) film was synthesized as a binder-free cathode for solid-state aqueous ZIBs. The addition of PVA not only increases the layer spacing of VOH and forms a strong hydrogen bond network with GO and water molecules, but also enhances the mechanical properties of the film. As a binder-free cathode for solid-state aqueous ZIBs, the VOH/rGO-P film attains excellent electrochemical capacity as high as 481 mAhâg-1 at 0.1 Aâg-1. Such a high specific capacity indicates that the VOH/rGO-P film shows great potential for the next generation solid-state aqueous ZIBs.
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Exploring electrode materials with excellent electrochemical performance is the key to the development of applications in energy storage and conversion. Herein, three-dimensional (3D) vanadium sulfide/carbon nanotubes/reduced graphene oxide (VS4/CNTs/rGO) composite is synthesized by a simple one-step hydrothermal method. VS4 short nanorods cover the both sides of the rGO sheets, and CNTs distribute at the edge of the composite to form a sandwich-like structure, which effectively prevents the accumulation of rGO. Due to the special 3D hierarchical structure, VS4/CNTs/rGO exhibits a large specific surface area and a rich pore structure, and the addition of CNTs and rGO also improves the electrochemical properties of VS4. At 1 A·g-1, VS4/CNTs/rGO exhibits a capacitance of 497 F·g-1 (1374.0 C·g-1) in the voltage range of -1.4 to 1.4 V, which is much higher than those binary materials including CNTs/rGO, VS4/CNTs and VS4/rGO. The VS4/CNTs/rGO symmetric supercapacitor (SSC) device shows a remarkable electrochemical performance in a large potential window up to 2.2 V. The capacitance of VS4/CNTs/rGO SSC device can reach 1003.5 mF·cm-2 (2207.6 mC·cm-2) at 0.5 mA·cm-2, and it exhibits an energy density of 6.75 Wh·m-2 (72.07 Wh·kg-1) at a power density of 1.38 W·m-2 (14.69 W·kg-1). The high capacitance and energy density of the VS4/CNTs/rGO composite in the high voltage interval make it as the potential energy storage material.