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Breast cancer is the most common female malignancy worldwide. Ubiquitin-specific peptidase 53 (USP53) has been shown to exert cancer-suppressing functions in several solid tumors, but its role and the underlying mechanism in breast cancer has not been clearly elucidated. Therefore, we have carried out a series of detailed studies on this matter at the levels of bioinformatics, clinical tissue, cell function and animal model. We found that USP53 expression was downregulated in breast cancer specimens and was negatively correlated with the clinical stages. Gain- and loss-of-function experiments demonstrated USP53 inhibited proliferation, clonogenesis, cell cycle and xenograft growth, as well as induced apoptosis and mitochondrial damage of breast cancer cells. Co-immunoprecipitation data suggested that USP53 interacted with zinc finger MYND-type containing 11 (ZMYND11), and catalyzed its deubiquitination and stabilization. The 33-50 amino acid Cys-box domain was key for USP53 enzyme activity, but not essential for its binding with ZMYND11. The rescue experiments revealed that the anti-tumor role of USP53 in breast cancer cells was at least partially mediated by ZMYND11. Both USP53 and ZMYND11 were prognostic protective factors for breast cancer. USP53-ZMYND11 axis may be a good potential biomarker or therapeutic target for breast cancer, which can provide novel insights into the diagnosis, treatment and prognosis.
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Optimizing the electronic structure of electrocatalysts is of particular importance to enhance the intrinsic activity of active sites in water/seawater. Herein, a series of medium-entropy metal oxides of X(NiMo)O2/NF (X = Mn, Fe, Co, Cu and Zn) is designed via a rapid carbothermal shocking method. Among them, the optimized medium-entropy metal oxide (FeNiMo)O2/NF delivered remarkable HER performance, where the overpotentials as low as 110 and 141 mV are realized at 1000 mA cm-2 (@60 °C) in water and seawater. Meanwhile, medium-entropy metal oxide (FeNiMo)O2/NF only required overpotentials of as low as 330 and 380 mV to drive 1000 mA cm-2 for OER in water and seawater (@60 °C). Theoretical calculations showed that the multiple-metal synergistic effect in medium-entropy metal oxides can effectively enhance the d-p orbital hybridization of MoâO bond, reduce the energy barrier of H* adsorbed at the Mo sites. Meanwhile, Fe sites in medium-entropy metal oxide can act as the real OER active center, resulting in a good bifunctional activity. In all, this work provides a feasible strategy for the development of highly active and stable medium-entropy metal oxide electrocatalysts for ampere-level water/seawater splitting.
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Aiming to improve the photocatalytic activity in N2 fixation to produce ammonia, herein, we proposed a photochemical strategy to fabricate defects, and further deposition of Ru single atoms onto UiO-66 (Zr) framework. Electron-metal-support interactions (EMSI) were built between Ru single atoms and the support via a covalently bonding. EMSI were capable of accelerating charge transfer between Ru SAs and UiO-66, which was favorable for highly-efficiently photocatalytic activity. The photocatalytic production rate of ammonia improved from 4.57â µmol g-1 h-1 to 16.28â µmol g-1 h-1 with the fabrication of defects onto UiO-66, and further to 53.28â µmol g-1 h-1 with Ru-single atoms loading. From the DFT results, it was found that d-orbital electrons of Ru were donated to N2 πâ¶-antibonding orbital, facilitating the activation of the N≡N triple bond. A distal reaction pathway was probably occurred for the photocatalytic N2 reduction to ammonia on Ru1 /d-UiO-66 (single Ru sites decorated onto the nodes of defective UiO-66), and the first step of hydrogenation of N2 was the reaction determination step. This work shed a light on improving the photocatalytic activity via feasibly anchoring single atoms on MOF, and provided more evidences to understand the reaction mechanism in photocatalytic reduction of N2 .
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Coastal ecosystems offer substantial support and space for the sustainable development of human society, and hence the ecological risk evaluation of coastal ecosystems is of great significance. In this article, we propose an innovative framework for evaluating coastal ecological risk by considering oil spill risk information and environmental vulnerability information. Specifically, a deep learning based marine oil spill monitoring method is presented to obtain the oil spill risk information from Sentinel-1 polarimetric synthetic aperture radar (PolSAR) images. The environmental vulnerability information is then obtained from biological sample data and habitat information. Finally, a weighted probability model is introduced to utilize the oil spill risk and environmental vulnerability information, to evaluate the coastal ecological risk. In the experimental part, the proposed oil spill monitoring method shows its reliability in global ocean areas, and the proposed model is adopted to evaluate the ecological risk in Jiaozhou Bay, China. The results show that the ecological situation of more than half of the areas in Jiaozhou Bay is unstable, and the areas with high risk are mainly concentrated in the ports, shipping channels, and those areas with high biodiversity. This study provides some new perspectives on ecological risk assessment for coastal ecosystems, facilitating the planning process and the actions to be taken in response to the accidents that occur in the ocean, especially oil spill accidents.
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Contaminación por Petróleo , Humanos , Radar , Ecosistema , Reproducibilidad de los Resultados , Medición de RiesgoRESUMEN
This paper reports on a Bi2MoxW1-xO6 solid solution with excellent photocatalytic activity in CO2 reduction. Under simulated sunlight, the Bi2Mo0.25W0.75O6 solid solution achieved a CO generation yield of ≤298.2 µmol g-1 over 3 h, which was 2.1 and 1.5 times larger than those of pristine Bi2WO6 and Bi2MoO6, respectively. Via an in-depth study of the mechanism, this excellent photocatalytic activity was determinied to be probably due to two major contributions: (1) the formation of oxygen vacancies on the Bi2Mo0.25W0.75O6 solid solution, which provided more reactive sites for adsorption and activation of CO2, and (2) modulation of the electronic band structure, which facilitated charge separation. Mechanistic and reaction pathways have been deeply explored and proposed.
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BACKGROUND: Inguinal hernia repair is one of the most commonly performed surgical procedures. To date, there is no consensus on which anesthesia should be used. The objective of this meta-analysis was to assess the efficacy of spinal anesthesia (SA) vs. general anesthesia (GA) in inguinal hernia repair in adults. METHODS: Eligible studies were identified before January 2020 from PubMed, Embase, ScienceDirect, Cochrane Library, Scopus database as well as reference lists. Outcomes included surgery time, the time in the operation room, the length of hospital stay, pain scores, patient satisfaction, and postoperative complications. Subgroup analysis based on surgical approaches was conducted. RESULTS: Six randomized controlled trials (RCT) and five cohort studies were included. A total of 2593 patients were analyzed. Compared to GA, SA was associated with a longer surgery time (weighted mean difference [WMD]: - 3.28, 95%confident interval [CI]: - 5.76, - 0.81), particularly in laparoscopic repair. Postoperative pain at 4 h and 12 h were in favor of SA following either open or laparoscopic repairs (standard mean difference [SMD]: 1.58; 95%CI: 0.55, 2.61, SMD: 0.99, 95%CI: 0.37, 1.60, respectively); and considering borderline significance, patients receiving SA might be more satisfied with the anesthesia they used for herniorrhaphy (SMD: -0.32, 95%CI: - 0.70, 0.06). Some major complications of scrotal edema, seroma, wound infection, recurrence, shoulder pain were comparable between the two groups. However, patients receiving SA had an increased risk of postoperative urinary retention and headache when compared with GA (relative ratio [RR]: 0.44, 95% CI: 0.23, 0.86, RR: 0.33, 95% CI: 0.12, 0.92, respectively). There was a tendency that the incidence of postoperative nausea and vomiting was lower in SA than GA (RR: 2.12, 95%CI: 0.95, 4.73), especially in open herniorrhaphy. CONCLUSIONS: SA can be another good choice for pain relief no matter in open or laparoscopic hernia repairs, but it can't be confirmed that SA is better than GA.
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Anestesia General/métodos , Anestesia Raquidea/métodos , Hernia Inguinal/cirugía , HumanosRESUMEN
The Hippo-Mst1 pathway is associated with tumor development and progression. However, little evidence is available for its role in colorectal cancer (CRC) stress response via mitochondrial homeostasis. In this study, we conducted gain-of function assay about Mst1 in CRC via adenovirus transfection. Then, cellular viability and apoptosis were measured via MTT, TUNEL assay, and typan blue staining. Mitochondrial function was detected via JC1 staining, mPTP opening assay, and immunofluorescence of cyt-c. Mitophagy was observed via western blots and immunofluorescence. Cell migration and proliferation were evaluated via Transwell and BrdU assay. Western blots were used to analyze the signaling pathways with JNK inhibitors or p53 siRNA. We found that Mst1 was down-regulated in CRC. Overexpression of Mst1 induced CRC apoptosis and impaired cell proliferation and migration. Functional studies have illustrated that recovery of Mst1 could activate JNK pathway which upregulated the p53 expression. The latter repressed Bnip3 transcription and activity, leading to the mitophagy arrest. The defective mitophagy impaired mitochondrial homeostasis, evoked cellular oxidative stress, and initiated the mitochondrial apoptosis. Meanwhile, bad-structured mitophagy also hindered the cancer proliferation via CyclinD/E. Moreover, Mst1-suppressed mitophagy was associated with CRC migration inhibition via regulation of CXCR4/7 expression. Collectively, our data described the comprehensive role of Mst1 in colorectal cancer stress response involving apoptosis, mobilization, and growth via handling mitophagy by JNK/p53/Bnip3 pathways.
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Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Sistema de Señalización de MAP Quinasas , Proteínas de la Membrana/metabolismo , Mitofagia , Estrés Oxidativo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Regulación hacia Abajo , Homeostasis , Humanos , Péptidos y Proteínas de Señalización Intracelular , Mitocondrias/metabolismo , Modelos BiológicosRESUMEN
Although hypoxia-inducible factor-lα (HIF-lα) has been reported to have an important role in the metabolism and synthesis of the extracellular matrix (ECM) of nucleus pulposus cells (NPCs), the underlying mechanism has not been fully clarified. Here, we show for the first time that NOTCH1 expression is decreased in NPs isolated from degenerated human intervertebral discs (IVDs), as well as in the NPs of NP-specific HIF-1α-/- mice. Our study reveals that overexpression of HIF-1α leads to increased expression of NOTCH1, the NOTCH1 ligand JAGGED1, and its target gene hairy and enhancer of split-1 (HES1), while also upregulating collagen Π and aggrecan expression in human NPCs. Importantly, these changes in expression are significantly suppressed by the NOTCH1 inhibitor DAPT. In parallel with changes in collagen Π and aggrecan expression, inhibition of the HIF-1α-NOTCH1 pathway altered ECM turnover by suppressing expression of the matrix metalloproteinases MMP1 and MMP13, while increasing the expression of tissue inhibitor of metalloproteinase-1 (TIMP1). Lastly, activation of NOTCH1 via JAGGED1 in human NPCs isolated from degenerated IVDs restored collagen Π and aggrecan expression. Therefore, our study shows that HIF-1α regulates collagen Π and aggrecan expression through NOTCH1 signaling and implicate NOTCH1 as a potential therapeutic target in disc degeneration.
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Agrecanos/metabolismo , Colágeno Tipo II/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Degeneración del Disco Intervertebral/metabolismo , Núcleo Pulposo/metabolismo , Receptor Notch1/metabolismo , Transducción de Señal , Adolescente , Adulto , Anciano , Agrecanos/antagonistas & inhibidores , Agrecanos/genética , Animales , Células Cultivadas , Colágeno Tipo II/antagonistas & inhibidores , Colágeno Tipo II/genética , Diaminas/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Subunidad alfa del Factor 1 Inducible por Hipoxia/deficiencia , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Núcleo Pulposo/citología , Núcleo Pulposo/efectos de los fármacos , Receptor Notch1/antagonistas & inhibidores , Receptor Notch1/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Relación Estructura-Actividad , Tiazoles/farmacología , Adulto JovenRESUMEN
State-of-the-art pansharpening methods generally inject the spatial structures of a high spatial resolution (HR) panchromatic (PAN) image into the corresponding low spatial resolution (LR) multispectral (MS) image by an injection model. In this paper, a novel pansharpening method with an edge-preserving guided filter based on three-layer decomposition is proposed. In the proposed method, the PAN image is decomposed into three layers: A strong edge layer, a detail layer, and a low-frequency layer. The edge layer and detail layer are then injected into the MS image by a proportional injection model. In addition, two new quantitative evaluation indices, including the modified correlation coefficient (MCC) and the modified universal image quality index (MUIQI) are developed. The proposed method was tested and verified by IKONOS, QuickBird, and Gaofen (GF)-1 satellite images, and it was compared with several of state-of-the-art pansharpening methods from both qualitative and quantitative aspects. The experimental results confirm the superiority of the proposed method.
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The title compound, C17H19NO3S, was synthesized from 4-benzhydryl-idene-amino-12-hy-droxy-[2.2]para-cyclo-phane and methane-sulfonyl chloride. In the mol-ecule, the distance between the centroids of two aromatic rings is 2.960â (5)â Å. In the crystal, weak N-Hâ¯O and C-Hâ¯O hydrogen bonds link the mol-ecules into layers parallel to the ac plane.
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Multispectral (MS) images with high spatial resolution (HR) can be obtained by fusing MS images and panchromatic (PAN) image, the HR MS images have an important significance in image interpretation and classification, etc. In the present paper, a new image fusion method based on gradient consistency constraint for MS/PAN images is developed. The method is based on maximum a posteriori (MAP) framework. The relationship of desired HR MS images and PAN image is formulated by gradient consistency constraint. Observation model of MS images and the Huber-Markov priori are combined to solve the fused image by gradient descent algorithm. In the proposed method, gradient consistency constraint is introduced, and defect of band number restriction is overcomed in conventional model-based fusion methods. Iterative step for every band is solved adaptively, and spectral characteristics of each band are fully taken into account, so it not only ensures the spectral information fidelity, but also improves the integration degree of spatial information of fused image. The proposed method has been tested using IKONOS and WorldView-2 images. It is compared with GS, AIHS and AMBF fusion methods from both qualitative and quantitative aspects. Experimental results show that the proposed method can better preserve spectral information while enhance spatial resolution, and it has broader applicability and better fusion result than other methods.
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Ubiquitination and deubiquitination are important mechanisms to maintain normal physiological activities, and their disorders or imbalances can lead to various diseases. As a subgroup of deubiquitinases (DUBs), the ubiquitin-specific peptidase (USP) family is closely related to many biological processes. USP53, one of the family members, is widely expressed in human tissues and participates in a variety of life activities, such as cell apoptosis, nerve transmission, and bone remodeling. Mutations in the USP53 gene can cause cholestasis and deafness and may also be a potential cause of schizophrenia. Knockout of USP53 can alleviate neuropathic pain induced by chronic constriction injury. Loss of USP53 up-regulates RANKL expression, promotes the cytogenesis and functional activity of osteoclasts, and triggers osteodestructive diseases. USP53 plays a tumor-suppressive role in lung cancer, renal clear cell carcinoma, colorectal cancer, liver cancer, and esophageal cancer but reduces the radiosensitivity of cervical cancer and esophageal cancer to induce radioresistance. Through the in-depth combination of literature and bioinformatics, this review suggested that USP53 may be a good potential biomarker or therapeutic target for diseases.
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Neoplasias , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Animales , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proteasas Ubiquitina-Específicas/genética , Proteasas Ubiquitina-Específicas/metabolismo , Terapia Molecular Dirigida/métodos , Ubiquitinación , Mutación , Colestasis/genética , Colestasis/metabolismo , Colestasis/patologíaRESUMEN
Molybdenum dioxide (MoO2) has been considered as a promising hydrogen evolution reaction (HER) electrocatalyst. However, the active sites are mainly located at the edges, resulting in few active sites and poor activity in the HER. Herein, we first reported on an efficient strategy to incorporate Fe into MoO2 nanosheets on Ni foam (Fe-MoO2/NF) using a rapid carbothermal shocking method (820 °C for 127 s). Notably, the different spin states between Fe and Mo atoms could lead to rich lattice dislocations in Fe-MoO2/NF, exposing abundant oxygen vacancies and the low-oxidation-state of Mo sites during the rapid Joule heating process. As tested, the catalyst exhibited superior activity with ultralow overpotentials (HER: 17 mV@10 mA cm-2; oxygen evolution reaction (OER): 310 mV@50 mA cm-2) and high OER selectivity in alkaline seawater splitting. Meanwhile, this catalyst was equipped in a home-made anion exchange membrane (AEM) seawater electrolyzer, which achieved a low energy consumption (5.5 kW h m-3). More importantly, Fe-MoO2/NF also coupled very well with a solar-driven electrolytic system and turned out a solar-to-hydrogen (STH) efficiency of 13.5%. Theoretical results also demonstrated that Fe incorporated and abundant oxygen vacancies in MoO2 can distort the distance of the Mo-O bonds and regulate the electronic structure, thus optimizing the binding energy of H*/OOH* adsorption. This method can be extended to other heterogeneous spin states in MoO2-based catalysts (e.g. Ni-MoO2/NF, Co-MoO2/NF) for seawater splitting, and provide a simple, efficient and universal strategy to prepare highly-efficient MoO2-based electrocatalysts.
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Rational design of bimetallic alloy is an effective way to improve the electrocatalytic activity and stability of Mo-based cathode for ampere-level hydrogen evolution. However, it is still critical to realise desirable syntheses due to the wide reduction potentials between different metal elements and uncontrollable nucleation processes. Herein, we propose a rapid Joule heating method to effectively load RuMo alloy onto MoOx matrix. As-prepared catalyst exhibits excellent stability (2000 h @ 1000 mA cm-2) and ultralow overpotential (9 mV, 18 mV and 15 mV in 1 M KOH, 1 M PBS, 0.5 M H2SO4 solution, respectively) at 10 mA cm-2. Based on first-principle simulations and operando measurements, the impressive electrocatalytic stability and activity are investigated. And the role of rapid Joule heating method is highlighted and discussed in details. This study showcases rapid Joule heating as a feasible strategy to construct highly efficient alloy-based electrocatalysts.
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Wear particles produced by joint replacements induce inflammatory responses that lead to periprosthetic osteolysis and aseptic loosening. However, the precise mechanisms driving wear particle-induced osteolysis are not fully understood. Recent evidence suggests that autophagy, a cellular degradation process, plays a significant role in this pathology. This study aimed to clarify the role of autophagy in mediating inflammation and osteolysis triggered by wear particles and to evaluate the therapeutic potential of zinc oxide nanoparticles (ZnO NPs). We incorporated ZnO into the prosthetic material itself, ensuring that the wear particles inherently carried ZnO, providing a targeted and sustained intervention. Our findings reveal that polymer wear particles induce excessive autophagic activity, which is closely associated with increased inflammation and osteolysis. We identified secretory autophagy as a key mechanism for IL-1ß secretion, exacerbating osteolysis. Both in vitro and in vivo experiments demonstrated that ZnO-doped particles significantly inhibit autophagic overactivation, thereby reducing inflammation and osteolysis. In summary, this study establishes secretory autophagy as a critical mechanism in wear particle-induced osteolysis and highlights the potential of ZnO-doped prosthetic polymers for targeted, sustained mitigation of periprosthetic osteolysis.
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BACKGROUND AND OBJECTIVE: The effectiveness of radiofrequency ablation (RFA) in improving long-term survival outcomes for patients with a solitary hepatocellular carcinoma (HCC) measuring 5 cm or less remains uncertain. This study was designed to elucidate the impact of RFA therapy on the survival outcomes of these patients and to construct a prognostic model for patients following RFA. METHODS: This study was performed using the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2017, focusing on patients diagnosed with a solitary HCC lesion ≤5 cm in size. We compared the overall survival (OS) and cancer-specific survival (CSS) rates of these patients with those of patients who received hepatectomy, radiotherapy, or chemotherapy or who were part of a blank control group. To enhance the reliability of our findings, we employed stabilized inverse probability treatment weighting (sIPTW) and stratified analyses. Additionally, we conducted a Cox regression analysis to identify prognostic factors. XGBoost models were developed to predict 1-, 3-, and 5-year CSS. The XGBoost models were evaluated via receiver operating characteristic (ROC) curves, calibration plots, decision curve analysis (DCA) curves and so on. RESULTS: Regardless of whether the data were unadjusted or adjusted for the use of sIPTWs, the 5-year OS (46.7%) and CSS (58.9%) rates were greater in the RFA group than in the radiotherapy (27.1%/35.8%), chemotherapy (32.9%/43.7%), and blank control (18.6%/30.7%) groups, but these rates were lower than those in the hepatectomy group (69.4%/78.9%). Stratified analysis based on age and cirrhosis status revealed that RFA and hepatectomy yielded similar OS and CSS outcomes for patients with cirrhosis aged over 65 years. Age, race, marital status, grade, cirrhosis status, tumor size, and AFP level were selected to construct the XGBoost models based on the training cohort. The areas under the curve (AUCs) for 1, 3, and 5 years in the validation cohort were 0.88, 0.81, and 0.79, respectively. Calibration plots further demonstrated the consistency between the predicted and actual values in both the training and validation cohorts. CONCLUSION: RFA can improve the survival of patients diagnosed with a solitary HCC lesion ≤5 cm. In certain clinical scenarios, RFA achieves survival outcomes comparable to those of hepatectomy. The XGBoost models developed in this study performed admirably in predicting the CSS of patients with solitary HCC tumors smaller than 5 cm following RFA.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Aprendizaje Automático , Ablación por Radiofrecuencia , Humanos , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Femenino , Persona de Mediana Edad , Ablación por Radiofrecuencia/métodos , Anciano , Pronóstico , Estudios Retrospectivos , Programa de VERF , Resultado del Tratamiento , Adulto , Curva ROCRESUMEN
BACKGROUND: Heart failure (HF) is a disease that poses a serious threat to individual health, and DNA methylation is an important mechanism in epigenetics, and its role in the occurrence and development of the disease has attracted more and more attention. The aim of this study was to evaluate the link between iodothyronine deiodinase 3 promoter region fragment FA27 (DIO3-FA27) methylation levels, biochemical indices, and HF. RESULTS: The methylation levels of DIO3-FA27_CpG_11.12 and DIO3-FA27_CpG_23.24 significantly differed in HF patients with different degrees. Multivariate logistic regression analysis indicated that the relative HF risk in the third and fourth quartiles of activated partial thromboplastin time and fibrin degradation products. The results of the restricted cubic spline model showed that the methylation levels of DIO3-FA 27_CpG_11.12 and DIO3-FA 27_CpG_23.24 were associated with coagulation indicators, liver function, renal function, and blood routine. CONCLUSIONS: Based on the differential analysis of CpG methylation levels based on DIO3-FA27, it was found that biochemical indicators combined with DIO3-FA27 promoter DNA methylation levels could increase the risk of worsening the severity classification of HF patients, which provided a solid foundation and new insights for the study of epigenetic regulation mechanisms in patients with HF.
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Metilación de ADN , Progresión de la Enfermedad , Epigénesis Genética , Insuficiencia Cardíaca , Yoduro Peroxidasa , Regiones Promotoras Genéticas , Humanos , Insuficiencia Cardíaca/genética , Metilación de ADN/genética , Masculino , Femenino , Yoduro Peroxidasa/genética , Persona de Mediana Edad , Anciano , Epigénesis Genética/genética , Islas de CpG/genéticaRESUMEN
Hydrogen generation by photocatalysis is one of the most effective approaches to rationally utilize solar energy. In this work, we designed a biphasic photothermal-photocatalytic system. Spherical g-C3N4 (HCN) was grown on the carbonized wood (CW) by a one-step hydrothermal method. The carbonization layer in carbonized wood/spherical g-C3N4 (CW-HCN) system was able to further enhance the photothermal conversion of water steam production by improving the absorption of solar radiation. In addition, the temperature was increased due to photothermal effect, which was beneficial for H2 evolution reaction. Moreover, the carbonized layer could act as a reservoir for photogenerated electrons on g-C3N4, which could accelerate the charge separation. Benefiting from all above-mentioned merits, the H2 evolution rate of CW-HCN system under simulated sunlight reached 2700.18 µmol/m2/h, which was 42.23 times higher than that of pristine g-C3N4 powder directly dispersed in water. In addition, the CW-HCN system exhibited broad applicability, maintaining the H2 evolution activity of 2013.29 µmol/m2/h with seawater as water resource. This work provided a new strategy for highly efficient H2 evolution.
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A novel slant perforated mesh-plate photoreactor (SPPR) was designed and fabricated. The central assembly of SPPR was an array of slant perforated mesh-plate coated with TiO2 (P25). The performance of SPPR in water detoxification was evaluated with regard to the degradation of phenol as the target pollutant. The effects of slant plate tilt angle (α) and perforated plate opening aperture diameter on SPPR performance were investigated and analyzed. The photocatalytic performance of SPPR increased with decreasing α. The SPPR with an α of 15° and a pore size of 1 mm showed the best performance with 9.17 h required to reach 80% of phenol degradation (4-L, initial concentration: 15 mg/L). The mass transfer was introduced into the kinetic reaction model, and mass transfer coefficients were calculated for SPPRs with different structures. Flow rate and initial pollutant concentration were investigated for their effects on degradation efficiency. In addition, the activity of SPPR under natural sunlight has also been tested to explore its potential to be applied in practice.
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Contaminantes Ambientales , Contaminantes Químicos del Agua , Agua/química , Titanio/química , Luz Solar , Fenoles , Catálisis , Contaminantes Químicos del Agua/químicaRESUMEN
Two-dimension (2D) MXene materials have increasingly attracted attentions in improving the photocatalytic conversion of solar-to-chemical energy over graphitic carbon nitride (g-C3N4). In this work, Pt nanoparticles modified few-layer Ti3C2 MXene sheet (MXene@Pt) was successfully prepared by chemical reduction, which was used as efficient co-catalysts to enhance the photocatalytic hydrogen evolution over porous g-C3N4 (PCN). The high work function of MXene@Pt and the tight 2D/2D interfacial contact between MXene@Pt and PCN significantly promoted the transfer and separation of photogenerated electron-hole. Besides, the MXene@Pt could enhance the light-harvesting of PCN and provide plentiful active sites for hydrogen evolution reaction. The hydrogen evolution activity of optimum 2D/2D MXene@Pt modified PCN (PCN/MPt-5) composite was dramatically enhanced, even higher than that of equal Pt mass modified PCN. Besides, overall water splitting was realized via a two-electron pathway with H2O2 and H2 generation. This work may provide the fabrication strategy for developing MXene-based co-catalyst in photocatalysis.