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Constructing the plasmonic metal/semiconductor heterostructure with a suitable Schottky barrier height (SBH) and the sufficiently reliable active sites is of importance to achieve highly efficient and selective photocatalytic CO2 reduction into hydrocarbon fuels. Herein, we report Au/sulfur vacancy-rich ZnIn2S4 (Au/VSR-ZIS) hierarchical photocatalysts, fabricated via in situ photodepositing Au nanoparticles (NPs) onto the nanosheet self-assembled ZnIn2S4 (ZIS) micrometer flowers (MFs) with rich sulfur vacancies (VS). Density functional theory (DFT) calculations confirm that for the Au/VSR-ZIS system, the Au NPs serve as the reaction sites for H2O oxidation, and the VSR-ZIS MFs serve as those for CO2 reduction. The rich VS in the Au/VSR-ZIS hybrid can reduce its SBH so as to boost more hot electrons in the Au NPs across its Schottky barrier and then inject into the conduction band (CB) of the VSR-ZIS MFs. In addition, VS can also act as the electron sink to trap the photogenerated electrons, retarding the recombination of photogenerated carriers. The two merits effectively enhance the photogenerated electron density in the surface of VSR-ZIS MFs, availing CO2 photoreduction. In addition, the introduction of rich VS in the Au/VSR-ZIS hybrid can offer more active sites, benefiting the CO2 adsorption and accelerating the desorption of CO* from the surface of the photocatalyst. Therefore, under visible light illumination with no sacrificial reagent, the optimum photocatalyst (Au/VSR-ZIS-0.4) presents the enhanced and selective CO2 photoreduction into CO (8.15 µmol g-1h-1 and near 100%), which are superior to those of most of ZIS-based and plasmon-based photocatalysts. The photocatalytic activity is about 40.0-fold as high as that of the Vs-poor-ZIS (VSP-ZIS) MFs. This work contributes a viable strategy for designing highly efficient plasmonic photocatalysts by using the synergism of the anion vacancies and the optimized SBH induced by them.
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BACKGROUND: The pathogenesis of diabetic cardiomyopathy is closely linked to abnormal glycosylation modifications. N-acetylglucosaminyltransferase V (GnT-V), which catalyzes the production of N-linked -1-6 branching of oligosaccharides, is involved in several pathophysiological mechanisms of many disorders, including cardiac hypertrophy and heart failure. However, the mechanism by which GnT-V regulates cardiac hypertrophy in diabetic cardiomyopathy is currently poorly understood. In this study, we investigated the role of GnT-V on myocardial hypertrophy in diabetic cardiomyopathy and elucidated the underlying mechanisms. MATERIAL AND METHODS: Streptozotocin (STZ) was intraperitoneally injected into mice to induce diabetic cardiomyopathy. An adeno-associated virus (AAV) carrying negative control small hairpin RNA (shNC) or GnT-V-specifc small hairpin RNA (shGnT-V) was used to manipulate GnT-V expression. In our study, forty male C57BL/6J mice were randomly divided into four groups (10 mice per group): control mice with AAV-shNC, diabetic cardiomyopathy mice with AAV-shNC, control mice with AAV-shGnT-V, and diabetic cardiomyopathy mice with AAV-shGnT-V. In addition, H9C2 cells and primary neonatal cardiac fibroblasts treated with high glucose were used as a cell model of diabetes. Analysis of cardiac hypertrophy and fibrosis, as well as functional studies, were used to investigate the underlying molecular pathways. RESULTS: AAV-mediated GnT-V silencing dramatically improved cardiac function and alleviated myocardial hypertrophy and fibrosis in diabetic mice. In vitro experiments demonstrated that GnT-V was elevated in cardiomyocytes and induced cardiomyocyte hypertrophy in response to high glucose stimulation. GnT-V knockdown significantly reduced the expression of the integrinß1 signaling pathway, as evidenced by decreased downstream ERK1/2 activity, which inhibited cardiomyocyte hypertrophy accompanied by reduced ANP, BNP, and ß-MHC expression. Furthermore, knocking down GnT-V expression lowered the TGF-ß1-Smads signaling pathway, which reduced the expression of α-SMA, collagen I, and collagen III. CONCLUSIONS: Overall, our research indicated that GnT-V may be a useful therapeutic target to treat diabetic cardiomyopathy, primarily in the inhibition of myocardial hypertrophy and fibrosis.
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Transcatheter aortic valve implantation (TAVI) was originally devised as a treatment for patients with aortic stenosis (AS). It has since emerged as a beneficial alternative to surgical aortic valve replacement (SAVR), extending its reach to a broader array of patients. Our objective was to illustrate the developmental trends and focus areas in TAVI research. We sourced a total of 11,480 research papers on TAVI, published between 1994 and 2022, from the Web of Science Core Collection (WoSCC) database. We conducted a bibliometric analysis of these publications, generating cooperation maps, performing co-citation analysis of journals and references, and carrying out a cluster analysis of keywords. Our findings indicate that TAVI research grapples with numerous clinical challenges. We created knowledge maps that highlight contributing countries/institutions, authors, journals with high publication and citation rates, and notable references in this domain. North America and Europe have been at the forefront of research within the TAVI field. The institutions and authors from these regions exert significant influence in this area of study. Beginning in 2009, China has progressively expanded its research on TAVI over the past two decades. We anticipate that future research will increasingly focus on three key areas: implementation scope, lifelong management, outcomes and predicting the risk of TAVI. Research on TAVI is flourishing. Cooperation among different countries and institutions in this field must be strengthened in the future, especially for developing counties.
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BACKGROUND: Ferroptosis, an emerging nonapoptotic, modulated cell death process characterized by iron accumulation and subsequent lipid peroxidation, has been intimately implicated in the development and progression of ovarian cancer (OC). Daphnetin (Daph), a natural product isolated from Daphne Korean Nakai, exhibits anticancer efficacy against various solid tumors. However, the specific role and potential mechanism underlying Daph-mediated modulation of ferroptosis in OC cells remain elusive. PURPOSE: This study aims to analyze the proferroptotic impacts of Daph on OC cells and to further explore the underlying mechanisms involved. STUDY DESIGN AND METHODS: We used CCK-8, wound healing and Transwell assays to assess whether Daph can inhibit the proliferation and migration of OC cells. Additionally, transmission electron microscopy (TEM), iron measurement, reactive oxygen species (ROS) analysis, lipid peroxidation assays, qRT-PCR and western blotting were utilized to evaluate the impact of Daph on ferroptosis and elucidate the potential underlying mechanism. Furthermore, RNA sequencing analysis, molecular docking analysis, cellular thermal shift assays (CETSAs) and NQO1 activity assays were used to predict and validate the binding and mechanistic interactions between Daph and NQO1. Subcutaneous tumorigenesis models were utilized to examine the effectiveness of Daph (and/or cisplatin) in vivo. RESULTS: Daph exerted antitumor effects by inducing the death and suppressing the migration of A2780 and SKOV3 cells. Further, Daph induced ferroptosis in OC cells, as evidenced by the accumulation of intracellular ferrous iron (Fe2+), ROS and lipid peroxides, as well as the decreases in the glutathione/oxidized glutathione disulfide (GSH/GSSG) ratio and the expression of ferroptosis indicators (SLC7A11 and GPX4). RNA sequencing and molecular docking analyses revealed that the direct interaction between NQO1 and Daph reduced both the activity and expression of NQO1. Importantly, NQO1 overexpression effectively alleviated the effects of Daph on proliferation, migration, and ferroptosis in vitro and in vivo. Interestingly, we also found that combination treatment with Daph, a negative regulator of NQO1, and cisplatin synergistically induced cytotoxicity in OC cells. CONCLUSION: Our findings are the firstly demonstrated that Daph acts as a novel ferroptosis inducer in OC cells by specifically targeting NQO1 and is thus a promising candidate agent for OC treatment.
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Introduction: Clinical significance of coagulase-negative staphylococci (CoNS) has been gradually acknowledged in both healthcare and clinical research, but approaches for their precise discrimination at the species level remain scarce. The current study aimed to evaluate the association of CoNS with orthopedic infections, where accurate and prompt identification of etiology is crucial for appropriate diagnosis and treatment decision-making. Methods: A 16S rRNA-based quantitative PCR (qPCR) assay was developed for the detection of Staphylococcus genus and two panels of 3-plex qPCR assays for further differentiation of six CoNS species with remarkable clinical significance, including S. epidermidis, S. haemolyticus, S. simulans, S. hominis, S. capitis, and S. caprae. All the assays exhibited excellent analytical performance. ΔCq (quantification cycle) between 16S rRNA and CoNS species-specific targets was established to determine the primary CoNS. These methods were applied to detect CoNS in wound samples from orthopedic patients with and without infection. Results and discussion: Overall, CoNS were detected in 17.8% (21/118) of patients with clinically suspected infection and in 9.8% (12/123) of patients without any infection symptom (p < 0.05). Moreover, the association with infection was found to be bacterial quantity dependent. S. epidermidis was identified as the predominant species, followed by S. simulans, S. haemolyticus, and S. hominis. Male sex, open injury, trauma, and lower extremity were determined as risk factors for CoNS infections. CoNS-positive patients had significantly longer hospitalization duration (20 days (15, 33) versus 13 days (7, 22) for Staphylococcus-negative patients, p = 0.003), which could be a considerable burden for healthcare and individual patients. Considering the complex characteristics and devastating consequences of orthopedic infections, further expanding the detection scope for CoNS may be pursued to better understand the etiology of orthopedic infections and to improve therapeutic strategies.
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Introduction: Accurate identification of the etiology of orthopedic infection is very important for correct and timely clinical management, but it has been poorly studied. In the current study we explored the association of multiple bacterial pathogens with orthopedic infection. Methods: Hospitalized orthopedic patients were enrolled in a rural hospital in Qingdao, China. Wound or exudate swab samples were collected and tested for twelve bacterial pathogens with both culture and multiplex real time PCR. Results and discussion: A total of 349 hospitalized orthopedic patients were enrolled including 193 cases presenting infection manifestations upon admission and 156 with no sign of infection. Orthopedic infection patients were mainly male (72.5%) with more lengthy hospital stay (median 15 days). At least one pathogen was detected in 42.5% (82/193) of patients with infection while 7.1% (11/156) in the patients without infection (P < 0.001). S. aureus was the most prevalent causative pathogen (15.5%). Quantity dependent pathogen association with infection was observed, particularly for P. aeruginosa and K. pneumoniae, possibly indicating subclinical infection. Most of the patients with detected pathogens had a previous history of orthopedic surgery (odds ratio 2.8, P = 0.038). Pathogen specific clinical manifestations were characterized. Multiplex qPCR, because of its high sensitivity, superior specificity, and powerful quantification could be utilized in combination with culture to guide antimicrobial therapy and track the progression of orthopedic infection during treatment.
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Reação em Cadeia da Polimerase Multiplex , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , China/epidemiologia , Adulto , Bactérias/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Infecções Bacterianas/microbiologia , Infecções Bacterianas/diagnóstico , Hospitalização , Idoso de 80 Anos ou mais , Reação em Cadeia da Polimerase em Tempo Real , Hospitais RuraisRESUMO
FeâNâC is the most promising alternative to platinum-based catalysts to lower the cost of proton-exchange-membrane fuel cell (PEMFC). However, the deficient durability of FeâNâC has hindered their application. Herein, a TiN-doped FeâNâC (FeâNâC/TiN) is elaborately synthesized via the sol-gel method for the oxygen-reduction reaction (ORR) in PEMFC. The interpenetrating network composed by FeâNâC and TiN can simultaneously eliminate the free radical intermediates while maintaining the high ORR activity. As a result, the H2O2 yields of FeâNâC/TiN are suppressed below 4%, ≈4 times lower than the FeâNâC, and the half-wave potential only lost 15 mV after 30 kilo-cycle accelerated durability test (ADT). In a H2âO2 fuel cell assembled with FeâNâC/TiN, it presents 980 mA cm-2 current density at 0.6 V, 880 mW cm-2 peak power density, and only 17 mV voltage loss at 0.80 A cm-2 after 10 kilo-cycle ADT. The experiment and calculation results prove that the TiN has a strong adsorption interaction for the free radical intermediates (such as *OH, *OOH, etc.), and the radicals are scavenged subsequently. The rational integration of Fe single-atom, TiN radical scavenger, and highly porous network adequately utilize the intrinsic advantages of composite structure, enabling a durable and active Pt-metal-free catalyst for PEMFC.
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Direct ethanol fuel cells (DEFCs) play an indispensable role in the cyclic utilization of carbon resources due to its high volumetric energy density, high efficiency, and environmental benign character. However, owing to the chemically stable carbon-carbon (CâC) bond of ethanol, its incomplete electrooxidation at the anode severely inhibits the energy and power density output of DEFCs. The efficiency of CâC bond cleaving on the state-of-the-art Pt or Pd catalysts is reported as low as 7.5%. Recently, tremendous efforts are devoted to this field, and some effective strategies are put forward to facilitate the cleavage of the CâC bond. It is the right time to summarize the major breakthroughs in ethanol electrooxidation reaction. In this review, some optimization strategies including constructing core-shell nanostructure with alloying effect, doping other metal atoms in Pt and Pd catalysts, engineering composite catalyst with interface synergism, introducing cascade catalytic sites, and so on, are systematically summarized. In addition, the catalytic mechanism as well as the correlations between the catalyst structure and catalytic efficiency are further discussed. Finally, the prevailing limitations and feasible improvement directions for ethanol electrooxidation are proposed.
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The design of a low-platinum (Pt) proton-exchange-membrane fuel cell (PEMFC) can reduce its high cost. However, the development of a low-Pt PEMFC is severely hindered by the high oxygen transfer resistance in the catalyst layer. Herein, a carbon with interconnected and hierarchical pores is synthesized as a support for the low-Pt catalyst to lower the oxygen transfer resistance. A H2-air fuel cell assembled by Pt/hierarchical porous carbon shows 1610 mW/cm2 peak power density, 2230 mA/cm2 current density at 0.60 V, and only 18.4 S/m local oxygen transfer resistance with 0.10 mgPt/cm2 Pt loading at the cathode, which far exceeds those of various carbon black supports and commercially used Pt/C catalysts. Both the experimental and simulation results have shown the advancement of hierarchical pores toward the high efficiency of oxygen transportation.
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BACKGROUND: During aging, excessive ROS production in the kidneys leads to redox imbalance, which contributes to oxidative damage and impaired organ homeostasis. However, whether and how aging-related NOX4-Nrf2 redox imbalance increases susceptibility to cisplatin-induced acute kidney injury remain largely unknown. METHODS: In this study, we used cisplatin-challenged aging mouse models and senescent HK-2 cells to investigate the effects and mechanisms of aging on susceptibility to cisplatin-induced acute kidney injury. RESULTS: In vivo, we found that cisplatin stimulation caused more severe renal damage, oxidative stress, mitochondrial dysfunction and mitophagy impairment in aging mice than in young mice. Moreover, Nrf2 deficiency aggravated cisplatin-induced acute kidney injury by exacerbating NOX4-Nrf2 redox imbalance and defective mitophagy. In vitro experiments on D-gal-treated human renal tubular epithelial cells (HK-2) demonstrated that senescent renal epithelial cells exhibited increased susceptibility to cisplatin-induced apoptosis, NOX4-Nrf2 redox imbalance-mediated oxidative stress and defective mitophagy. Mechanistically, we found that knockdown of Nrf2 in HK2 cells resulted in increased ROS and aggravated mitophagy impairment, whereas these effects were reversed in NOX4-knockdown cells. CONCLUSION: The present study indicates that NOX4-Nrf2 redox imbalance is critical for mitophagy deficiency in aged renal tubular epithelial cells and is a therapeutic target for alleviating cisplatin-induced acute kidney injury in elderly patients.
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Injúria Renal Aguda , Cisplatino , Humanos , Camundongos , Animais , Idoso , Cisplatino/toxicidade , Cisplatino/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Mitofagia , Espécies Reativas de Oxigênio/metabolismo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Envelhecimento , Rim/metabolismo , Estresse Oxidativo , Oxirredução , NADPH Oxidase 4/metabolismoRESUMO
The question of whether community nucleic acid testing contributes to an increase in infections within residential compounds has not been definitively answered. Shanghai, one of the largest cities in China, conducted city-wide community testing during its lockdown from late March to May 2022. This situation provided a unique opportunity to examine the effect of community testing on infection rates, as the lockdown largely eliminated confounding factors such as citizen mobility. In our study, based on a survey of 208 residential compounds in Shanghai and the daily infection data during the lockdown period, we found a significant correlation between community testing and infection risk in these compounds. However, after addressing potential issues of reverse causality and sampling bias, we found no significant causal link between community testing and infection risk. Furthermore, we discovered that increased awareness of mask-wearing correlated with a decrease in infections within the residential compounds during community testing. This suggests that the perceived correlation between community testing and infection risk may be confounded by residents' adherence to mask-wearing practices. Our findings emphasize the need for public health decision-makers to reinforce the importance of mask-wearing during community testing, as a means to prevent infections among citizens.
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Ácidos Nucleicos , Cidades/epidemiologia , China/epidemiologia , Viés de SeleçãoRESUMO
Low mass transfer efficiency and unavoidable matrix effects seriously limit the development of rapid and accurate determination of biosensing systems. Herein, we have successfully constructed an ultra-rapid nanoconfinement-enhanced fluorescence clinical detection platform based on machine learning (ML) and DNA xerogel "probe", which was performed by detecting neutrophil gelatinase-associated lipocalin (NGAL, protein biomarker of acute kidney injury). By regulating pore sizes of the xerogels, the transfer of NGAL in xerogels can approximate that in homogeneous solution. Due to electrostatic attraction of the pore entrances, NGAL rapidly enriches on the surface and inside the xerogels. The reaction rate of NGAL and aptamer cross-linked in xerogels is also accelerated because of the nanoconfinement effect-induced increasing reactant concentration and the enhanced affinity constant KD between reactants, which can be promoted by â¼667-fold than that in bulk solution, thus achieving ultra-rapid detection (ca. 5 min) of human urine. The platform could realize one-step detection without sample pretreatments due to the antiligand exchange effect on the surface of N-doped carbon quantum dots (N-CQDs) in xerogels, in which ligand exchange between -COOH and underlying interfering ions in urine will be inhibited due to higher adsorption energy of -COOH on the N-CQD surface relative to the interfering ions. Based on the ML-extended program, the real-time analysis of the urine fluorescence spectra can be completed within 2 s. Interestingly, by changing DNA, aptamer sequences, or xerogel fluorescence intensities, the detection platform can be customized for targeted diseases.
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Injúria Renal Aguda , Pontos Quânticos , Humanos , Lipocalina-2 , Fluorescência , Injúria Renal Aguda/diagnóstico , DNA , Oligonucleotídeos , ÍonsRESUMO
The crucial issue restricting the application of direct ethanol fuel cells (DEFCs) is the incomplete and sluggish electrooxidation of ethanol due to the chemically stable C-C bond thereof. Herein, a unique ethylene-mediated pathway with a 100 % C1-selectivity for ethanol oxidation reaction (EOR) is proposed for the first time based on a well-structured Pt/Al2 O3 @TiAl catalyst with cascade active sites. The electrochemical in situ Fourier transform infrared spectroscopy (FTIR) and differential electrochemical mass spectrometry (DEMS) analysis disclose that ethanol is primarily dehydrated on the surface of Al2 O3 @TiAl and the derived ethylene is further oxidized completely on nanostructured Pt. X-ray absorption and density functional theory (DFT) studies disclose the Al component doped in Pt nanocrystals can promote the EOR kinetics by lowering the reaction energy barriers and eliminating the poisonous species. Strikingly, Pt/Al2 O3 @TiAl exhibits a specific activity of 3.83â mA cm-2 Pt , 7.4 times higher than that of commercial Pt/C and superior long-term durability.
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Emerging evidence has implicated the important role of fibrosis in diabetic cardiomyopathy (DCM), while the underlying mechanism remains unclear. Considering the distinct and overlapping roles of Cluster of Differentiation 147 (CD147) in the pathogenesis of fibrotic diseases, we aim to investigate the role of CD147 in the fibrosis of DCM and explore its underlying mechanism. AAV9-mediated cardiac-specific CD147 silencing attenuated cardiac fibrosis and cardiac function in diabetic mice. CD147 knockdown significantly inhibited high glucose (HG)-induced activation of CFs. Mechanistically, CD147 directly bound to type I transcription growth factor ß (TGF-ß) receptor I (ALK5), promoting ALK5 activation and endocytosis to induce SMAD2/3 phosphorylation and nuclear translocation. In addition, HG prevented the ubiquitin-proteasome-dependent degradation of CD147 by promoting GNT-V-mediated N-glycosylation. As a result, cardiac-specific CD147 overexpression in control mice mimicked diabetes-induced cardiac fibrosis, aggravating cardiac function. Importantly, CD147 was also upregulated in serum and myocardial specimens from patients with diabetes compared with non-diabetes, accompanied by echocardiographic indices of cardiac dysfunction and excessive collagen deposition. Our study provides the first evidence that CD147 acts as a pivotal factor to promote diabetic cardiac fibrosis, and may contribute to the development of future CD147-based therapeutic strategies for DCM.
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Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Camundongos , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Glicosilação , Coração , Cardiomiopatias Diabéticas/metabolismo , Fibrose , Miocárdio/metabolismoRESUMO
Background: ST-segment elevation myocardial infarction (STEMI) in young male patients accounts for a significant proportion of total heart attack events. Therefore, clinical awareness and screening for acute myocardial infarction (AMI) in asymptomatic patients at a young age is required. The gut microbiome is potentially involved in the pathogenesis of STEMI. The aim of the current study is to develop an early risk prediction model based on the gut microbiome and clinical parameters for this population. Methods: A total of 81 young males (age < 44 years) were enrolled in this study. Forty-one young males with STEMI were included in the case group, and the control group included 40 young non-coronary artery disease (CAD) males. To identify the differences in gut microbiome markers between these two groups, 16S rRNA-based gut microbiome sequencing was performed using the Illumina MiSeq platform. Further, a nomogram and corresponding web page were constructed. The diagnostic efficacy and practicability of the model were analyzed using K-fold cross-validation, calibration curves, and decision curve analysis (DCA). Results: Compared to the control group, a significant decrease in tendency regarding α and ß diversity was observed in patients in the case group and identified as a significantly altered gut microbiome represented by Streptococcus and Prevotella. Regarding clinical parameters, compared to the control group, the patients in the case group had a higher body mass index (BMI), systolic blood pressure (SBP), triglyceride (TG), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) and low blood urea nitrogen (BUN). Additionally, BMI and SBP were significantly (p<0.05) positively correlated with Streptococcus and [Ruminococcus]. Further, BMI and SBP were significantly (p<0.05) negatively correlated with Prevotella and Megasphaera. A significant negative correlation was only observed between Prevotella and AST (p < 0.05). Finally, an early predictive nomogram and corresponding web page were constructed based on the gut microbiome and clinical parameters with an area under the receiver-operating characteristic (ROC) curve (AUC) of 0.877 and a C-index of 0.911. For the internal validation, the stratified K-fold cross-validation (K = 3) was as follows: AUC value of 0.934. The calibration curves of the model showed good consistency between the actual and predicted probabilities. The DCA results showed that the model had a high net clinical benefit for use in the clinical setting. Conclusion: In this study, we combined the gut microbiome and common clinical parameters to construct a prediction model. Our analysis shows that the constructed model is a non-invasive tool with potential clinical application in predicting STEMI in the young males.
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Developing highly efficient photocatalysts toward synchronously removing heavy metals and organic pollutants is still a serious challenge. Herein, we depict hierarchical S-scheme heterostructured photocatalysts prepared via in situ anchoring UiO-66-NH2 nanoparticles onto the CdIn2S4 porous microsphere structures assembled with numerous nanosheets. In the mixed system of Cr(VI) and tetracycline (TC), the optimal photocatalyst (CIS@U66N-30) shows remarkable photocatalytic activities toward the synchronous removal of Cr(VI) (97.26%) and TC (close to 100% of) under visible-light irradiation for 60 min, being the best removal rates among those of the reported photocatalysts, and sustains the outstanding stability and reusability. Its reaction rate constants of Cr(VI) reduction and TC degradation are about 2.06 and 1.58 folds that in the single Cr(VI) and TC systems, respectively. The enhanced photocatalytic activities of CIS@U66N-30 mainly result from the following synergism: (1) its hierarchical structure offers abundant active sites, and the S-scheme migration mechanism of charge carriers in the heterostructure accelerates the separation and migration of the useful photoinduced electrons and holes with the high redox capability; (2) Cr(VI) and TC can serve as the electron scavenger for TC oxidation degradation and the hole and â¢OH scavenger for Cr(VI) reduction, respectively, further enhancing the separation and utilization efficiency of photoinduced electrons and holes. Besides, the possible TC degradation pathway and plausible S-scheme photocatalytic mechanism over CIS@U66N-30 for the concurrent elimination of Cr(VI) and TC are proposed.
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Cromo , Compostos Organometálicos , Catálise , Cromo/química , Tetraciclina , Luz , Compostos Organometálicos/química , AntibacterianosRESUMO
Under some unexpected conditions, drive rods and control-rod assemblies may not be disconnected. If this situation is not detected, the control rod will be lifted out of the reactor core together with the upper reactor internals. This situation will seriously affect the follow-up work and reduce the economy and safety protection of the nuclear power plant. To ensure safety, the tripping status must be checked after tripping. Follow-up work can be carried out after checking and confirming that all drive rods are in the tripping status. There are many problems for traditional inspection methods, such as misjudgment, low accuracy, and labor consumption. This paper proposes a visual inspection system for the uncoupling state of the control-rod drive rod of the nuclear reactor. The proposed method is based on the fitting model of the ellipse parameter of the drive-rod head and the height of the drive rod. The ellipse of the drive-rod head is firstly accurately detected. Then, a mathematical model between the ellipse parameter and the height of the drive rod is established. The measurement error caused by the swing of the head of the drive rod is eliminated. The accurate measurement of the height difference before and after the tripping of the drive rod is computed. Finally, the status of the uncoupling of the drive rod is judged according to the difference. Many experiments are carried out with our developed system. The experimental results show that the proposed system realizes remote operation, ensures the quality of trip-status inspection, improves work efficiency, and reduces the workload of staff.
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Centrais Nucleares , Reatores Nucleares , HumanosRESUMO
BACKGROUND: Cardiac fibrosis is a leading cause of cardiac dysfunction in patients with diabetes. However, the underlying mechanisms of cardiac fibrosis remain unclear. This study aimed to investigate the role of the long non-coding RNA (LncRNA) Airn in the pathogenesis of cardiac fibrosis in diabetic cardiomyopathy (DCM) and its underlying mechanism. METHODS: Diabetes mellitus (DM) was induced in mice by streptozotocin injection. An intramyocardial adeno-associated virus (AAV) was used to manipulate Airn expression. The functional significance and underlying mechanisms in DCM fibrosis were investigated both in vitro and in vivo. RESULTS: Diabetic hearts showed a significant impairment in cardiac function, accompanied by obviously increased cardiac fibrosis. Interestingly, lncRNA Airn expression was significantly decreased in both diabetic hearts and high glucose (HG)-treated cardiac fibroblasts (CFs). AAV-mediated Airn reconstitution prevented cardiac fibrosis and the development of DCM, while Airn knockdown induced cardiac fibrosis phenotyping DCM. As in vitro, Airn reversed HG-induced fibroblast-myofibroblast transition, aberrant CFs proliferation and section of collagen I. In contrast, Airn knockdown mimicked a HG-induced CFs phenotype. Mechanistically, we identified that Airn exerts anti-fibrotic effects by directly binding to insulin-like growth factor 2 mRNA-binding protein 2 (IMP2) and further prevents its ubiquitination-dependent degradation. Moreover, we revealed that Airn/IMP2 protected p53 mRNA from degradation in m6A manner, leading to CF cell cycle arrest and reduced cardiac fibrosis. As a result, ablation of p53 blunted the inhibitory effects of Airn on fibroblast activation and cardiac fibrosis. CONCLUSIONS: Our study demonstrated for the first time that Airn prevented the development of cardiac fibrosis in diabetic heart via IMP2-p53 axis in an m6A dependent manner. LncRNA Airn could be a promising therapeutic target for cardiac fibrosis in DCM.
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Diabetes Mellitus , Cardiomiopatias Diabéticas , RNA Longo não Codificante , Proteínas de Ligação a RNA , Proteína Supressora de Tumor p53 , Animais , Camundongos , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/patologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismoRESUMO
Novel MOF nanofilm arrays (NiCoBDC-Fc) were grown on Ni foam via a multiscale structural regulation strategy. The introduction of metal doping and defects regulated the morphology of NiBDC for increasing the exposure of electrochemically active sites and adjusted the electronic structure of the Ni active center, which enhanced the OER performance of NiCoBDC-Fc/NF.
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Myocardial infarction (MI) is a coronary artery-related disease and ranks as the leading cause of sudden death globally. Resveratrol (Res) is a bioactive component and has presented antioxidant, anti-inflammatory and anti-microbial properties. However, the effect of Res on ferroptosis during MI progression remains elusive. Here, we aimed to explore the function of Res in the regulation of ferroptosis and myocardial injury in MI. We observed that the treatment of Res attenuated the MI-related myocardium injury and fibrosis in the rats. The expression of collagen 1 and α-SMA was induced in MI rats, in which the treatment of Res could decrease the expression. Treatment of Res suppressed the levels of IL-6 and IL-1ß in MI rats. The GSH levels were inhibited and MDA, lipid ROS, and Fe2+ levels were induced in MI rats, in which the treatment of Res could reverse the phenotypes. Meanwhile, the expression of GPX4 and SLC7A11 was reduced in MI rats, while the treatment of Res could rescue the expression in the model. Meanwhile, Res relieved oxygen-glucose deprivation (OGD)-induced cardiomyocyte injury. Importantly, Res repressed OGD-induced cardiomyocyte ferroptosis in vitro. Mechanically, we identified that Res was able to enhance GPX4 expression by inducing KAT5 expression. We confirmed that KAT5 alleviated OGD-induced cardiomyocyte injury and ferroptosis. The depletion of KAT5 or GPX4 could reverse the effect of Res on OGD-induced cardiomyocyte injury. Thus, we concluded that Res attenuated myocardial injury by inhibiting ferroptosis via inducing KAT5/GPX4 in myocardial infarction. Our finding provides new evidence of the potential therapeutic effect of Res on MI by targeting ferroptosis.