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The evolutionarily conserved C-terminal binding protein (CtBP) has been well characterized as a transcriptional co-repressor. Herein, we report a previously unreported function for CtBP, showing that lowering CtBP dosage genetically suppresses Polycomb group (PcG) loss-of-function phenotypes while enhancing that of trithorax group (trxG) in Drosophila, suggesting that the role of CtBP in gene activation is more pronounced in fly development than previously thought. In fly cells, we show that CtBP is required for the derepression of the most direct PcG target genes, which are highly enriched by homeobox transcription factors, including Hox genes. Using ChIP and co-IP assays, we demonstrate that CtBP is directly required for the molecular switch between H3K27me3 and H3K27ac in the derepressed Hox loci. In addition, CtBP physically interacts with many proteins, such as UTX, CBP, Fs(1)h and RNA Pol II, that have activation roles, potentially assisting in their recruitment to promoters and Polycomb response elements that control Hox gene expression. Therefore, we reveal a prominent activation function for CtBP that confers a major role for the epigenetic program of fly segmentation and development.
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Proteínas de Drosophila , Genes Homeobox , Oxirredutases do Álcool , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Ligação Proteica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional/genéticaRESUMO
FAPbI3 stands out as an ideal candidate for the photoabsorbing layer of perovskite solar cells (PSCs), showcasing outstanding photovoltaic properties. Nonetheless, stabilizing photoactive α-FAPbI3 remains a challenge due to the lower formation energy of the competitive photoinactive δ-phase. In this study, we employ tetraethylphosphonium lead tribromide (TEPPbBr3) single crystals as templates for the epitaxial growth of PbI2. The strategic use of TEPPbBr3 optimizes the evolution of intermediates and the crystallization kinetics of perovskites, leading to high-quality and phase-stable α-FAPbI3 films. The TEPPbBr3-modified perovskite exhibits optimized carrier dynamics, yielding a champion efficiency of 25.13% with a small voltage loss of 0.34 V. Furthermore, the target device maintains 90% of its initial PCE under maximum power point (MPP) tracking over 1000 h. This work establishes a promising pathway through single crystal seed based epitaxial growth for achieving satisfactory crystallization regulation and phase stabilization of α-FAPbI3 perovskites toward high-efficiency and stable PSCs.
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The mitogen-activated protein kinase kinase kinase 18 (MAPKKK18) has been reported to play a role in abiotic stress priming in long-term abscisic acid (ABA) response including drought tolerance and leaf senescence. However, the upstream transcriptional regulators of MAPKKK18 remain to be determined. Here, we report ABA-responsive element binding factors (ABFs) as upstream transcription factors of MAPKKK18 expression. Mutants of abf2, abf3, abf4, and abf2abf3abf4 dramatically reduced the transcription of MAPKKK18. Our electrophoresis mobility shift assay and dual-luciferase reporter assay demonstrated that ABF2, ABF3, and ABF4 bound to ABA-responsive element cis-elements within the promoter of MAPKKK18 to transactivate its expression. Furthermore, enrichments of the promoter region of MAPKKK18 by ABF2, ABF3, and ABF4 were confirmed by in vivo chromatin immunoprecipitation coupled with quantitative PCR. In addition, we found that mutants of mapkkk18 exhibited obvious delayed leaf senescence. Moreover, a genetic study showed that overexpression of ABF2, ABF3, and ABF4 in the background of mapkkk18 mostly phenocopied the stay-green phenotype of mapkkk18 and, expression levels of five target genes of ABFs, that is, NYE1, NYE2, NYC1, PAO, and SAG29, were attenuated as a result of MAPKKK18 mutation. These findings demonstrate that ABF2, ABF3, and ABF4 act as transcription regulators of MAPKKK18 and also suggest that, at least in part, ABA acts in priming leaf senescence via ABF-induced expression of MAPKKK18.
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Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Folhas de Planta , Senescência Vegetal , Elementos Reguladores de Transcrição , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Senescência Vegetal/genética , Senescência Vegetal/fisiologia , Plantas Geneticamente Modificadas/metabolismo , Fatores de Transcrição/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologiaRESUMO
Lithium-sulfur (Li-S) batteries are highly considered as next-generation energy storage techniques. Weakly solvating electrolyte with low lithium polysulfide (LiPS) solvating power promises Li anode protection and improved cycling stability. However, the cathodic LiPS kinetics is inevitably deteriorated, resulting in severe cathodic polarization and limited energy density. Herein, the LiPS kinetic degradation mechanism in weakly solvating electrolytes is disclosed to construct high-energy-density Li-S batteries. Activation polarization instead of concentration or ohmic polarization is identified as the dominant kinetic limitation, which originates from higher charge-transfer activation energy and a changed rate-determining step. To solve the kinetic issue, a titanium nitride (TiN) electrocatalyst is introduced and corresponding Li-S batteries exhibit reduced polarization, prolonged cycling lifespan, and high actual energy density of 381 Wh kg-1 in 2.5 Ah-level pouch cells. This work clarifies the LiPS reaction mechanism in protective weakly solvating electrolytes and highlights the electrocatalytic regulation strategy toward high-energy-density and long-cycling Li-S batteries.
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The employment of doubled-haploid (DH) technology in maize has vastly accelerated the efficiency of developing inbred lines. The selection of superior lines has to rely on genotypes with genomic selection (GS) model, rather than phenotypes due to the high expense of field phenotyping. In this work, we implemented 'genome optimization via virtual simulation (GOVS)' using the genotype and phenotype data of 1404 maize lines and their F1 progeny. GOVS simulates a virtual genome encompassing the most abundant 'optimal genotypes' or 'advantageous alleles' in a genetic pool. Such a virtually optimized genome, although can never be developed in reality, may help plot the optimal route to direct breeding decisions. GOVS assists in the selection of superior lines based on the genomic fragments that a line contributes to the simulated genome. The assumption is that the more fragments of optimal genotypes a line contributes to the assembly, the higher the likelihood of the line favored in the F1 phenotype, e.g. grain yield. Compared to traditional GS method, GOVS-assisted selection may avoid using an arbitrary threshold for the predicted F1 yield to assist selection. Additionally, the selected lines contributed complementary sets of advantageous alleles to the virtual genome. This feature facilitates plotting the optimal route for DH production, whereby the fewest lines and F1 combinations are needed to pyramid a maximum number of advantageous alleles in the new DH lines. In summary, incorporation of DH production, GS and genome optimization will ultimately improve genomically designed breeding in maize. Short abstract: Doubled-haploid (DH) technology has been widely applied in maize breeding industry, as it greatly shortens the period of developing homozygous inbred lines via bypassing several rounds of self-crossing. The current challenge is how to efficiently screen the large volume of inbred lines based on genotypes. We present the toolbox of genome optimization via virtual simulation (GOVS), which complements the traditional genomic selection model. GOVS simulates a virtual genome encompassing the most abundant 'optimal genotypes' in a breeding population, and then assists in selection of superior lines based on the genomic fragments that a line contributes to the simulated genome. Availability of GOVS (https://govs-pack.github.io/) to the public may ultimately facilitate genomically designed breeding in maize.
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Melhoramento Vegetal , Zea mays , Genótipo , Haploidia , Fenótipo , Melhoramento Vegetal/métodos , Zea mays/genéticaRESUMO
The advent of full-length transcriptome sequencing technologies has accelerated the discovery of novel splicing isoforms. However, existing alternative splicing (AS) tools are either tailored for short-read RNA-Seq data or designed for human and animal studies. The disparities in AS patterns between plants and animals still pose a challenge to the reliable identification and functional exploration of novel isoforms in plants. Here, we developed integrated full-length alternative splicing analysis (iFLAS), a plant-optimized AS toolkit that introduced a semi-supervised machine learning method known as positive-unlabeled (PU) learning to accurately identify novel isoforms. iFLAS also enables the investigation of AS functions from various perspectives, such as differential AS, poly(A) tail length, and allele-specific AS (ASAS) analyses. By applying iFLAS to three full-length transcriptome sequencing datasets, we systematically identified and functionally characterized maize (Zea mays) AS patterns. We found intron retention not only introduces premature termination codons, resulting in lower expression levels of isoforms, but may also regulate the length of 3'UTR and poly(A) tail, thereby affecting the functional differentiation of isoforms. Moreover, we observed distinct ASAS patterns in two genes within heterosis offspring, highlighting their potential value in breeding. These results underscore the broad applicability of iFLAS in plant full-length transcriptome-based AS research.
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Processamento Alternativo , Transcriptoma , Humanos , Processamento Alternativo/genética , Transcriptoma/genética , Zea mays/genética , Perfilação da Expressão Gênica/métodos , Melhoramento Vegetal , Isoformas de Proteínas/genética , RNA Mensageiro/genética , Análise de Sequência de RNARESUMO
BACKGROUND & AIMS: Intrahepatic cholangiocarcinoma (iCCA) has two main histological subtypes: large and small duct-type iCCA, which are characterized by different clinicopathological features. This study was conducted with the purpose of expanding our understanding of their differences in molecular features and immune microenvironment. METHODS: We selected 132 patients who underwent radical surgery at our department between 2015 and 2021 for clinical and survival analyses. Whole-exome sequencing was performed to analyse mutational landscapes. Bulk RNA sequencing and single-cell RNA sequencing data were used for pathway enrichment and immune infiltration analyses based on differentially expressed genes. The function of PPP1R1B was analysed both in vitro and in vivo and the gene mechanism was further investigated. RESULTS: We found that large duct-type iCCA had worse overall survival and recurrence-free survival rates than small duct-type iCCA. Mutations in ARID1A, DOT1L and ELF3 usually occur in large duct-type iCCA, whereas mutations in IDH1 and BAP1 occur in small duct-type iCCA. Among the differentially expressed genes, we found that PPP1R1B was highly expressed in large duct-type iCCA tumour tissues. Expression of PPP1R1B promoted cell proliferation, migration and invasion and indicated a worse prognosis. A combination of USF2 with the promoter of PPP1R1B can enhance gene expression in iCCA, which may further affect the expression of genes such as AHNAK, C4BPA and activating the PI3K/AKT pathway. CONCLUSIONS: Our findings extend our understanding of large and small duct-type iCCA. In addition, PPP1R1B may serve as a potential marker and therapeutic target for large duct-type iCCA.
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Non-precious metal-based nitrogen-doped carbon (M-Nx/C) shows great potential as a substitute for precious metal Pt-based catalysts. However, the conventional pyrolytic methods for forming M-Nx/C active sites are prone to issues such as the lack of synergistic interactions among bimetallic atoms and the potential encasement of active sites, leading to compromised catalytic efficiency and hindered mass transfer. In this work, a highly active FeCo-N-C@U-AC electrocatalyst is developed with a high density of active sites, adequate exposure of catalytic sites, and robust mass transfer capability using the chemical vapor-phase deposition (CVD) technique. The resulting catalyst demonstrates impressive oxygen reduction reaction (ORR) catalytic performance and stability, with half-wave potentials of 0.820 V (0.1 M HClO4) and 0.911 V (0.1 M KOH), respectively. It also exhibits significantly enhanced stability, retaining 93.25% and 98.38% of current after continuous 50 000 s of durability testing, surpassing the retention rates of Pt/C (80.31% in HClO4 and 84.96% in KOH electrolytes). Notably, when employed as a cathode catalyst in proton exchange membrane fuel cells (PEMFCs) and zinc-air flow batteries (ZAFBs), the FeCo-N-C@U-AC catalyst delivers peak power densities of 859 and 162 mW·cm-2, respectively, showcasing competitive performance comparable to benchmark Pt/C.
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Adolescent and young adults (AYAs) belong to a unique category of patients diagnosed with acute lymphoblastic leukaemia (ALL). Bloodstream infection (BSI) is a leading cause of treatment-related mortality in ALL patients. However, the epidemiology and risk factors for mortality from BSIs in AYA patients remain unclear. In this study, we analysed these aspects in AYAs patients and compared similarities and differences with children (<15 years old) and older adults (>39 years old). We analysed the pathogenic epidemiology, antibiotic resistance and BSI risk factors of 73 children, 180 AYAs, and 110 older adults with ALL in three comprehensive hospitals from January 2010 to August 2021. The data on BSIs in AYAs were compared to that of the other two groups. In this study, the epidemiology of BSIs in AYAs was similar to that of older adult patients. Concerning clinical characteristics, most AYAs and older adults with BSIs were in a relapsed or uncontrolled state (34.5% vs. 35.4%, p = 0.861). In terms of pathogen distribution, Gram-negative bacteria (GNB) were the most common causative pathogens in AYAs and older adult groups. Extended-spectrum beta-lactamase (ESBL)-producing bacteria were more commonly found in AYAs than in children (32.8% vs. 16.4%, p = 0.09). Regarding risk factors, the length of hospitalization (>14 days) and renal inadequacy (creatinine ≥ 177 µmol/L) were influencing factors for 30-day mortality in AYAs patients with BSIs. In our study, AYA patients with BSIs showed clinical characteristics and pathogen distributions similar to those of older adult patients but quite different from those of children.
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Leucemia-Linfoma Linfoblástico de Células Precursoras , Sepse , Criança , Humanos , Adolescente , Adulto Jovem , Idoso , Adulto , Estudos Retrospectivos , Fatores de Risco , Bactérias , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologiaRESUMO
OBJECTIVES: There is limited evidence on sex, racial, and ethnic disparities in Emergency Department (ED) triage across diverse settings. We evaluated differences in the assignment of Emergency Severity Index (ESI) by patient sex and race/ethnicity, accounting for age, clinical factors, and ED operating conditions. METHODS: We conducted a multi-site retrospective study of adult patients presenting to high-volume EDs from January 2019-February 2020. Patient-level data were obtained and analyzed from three EDs (academic, metropolitan community, and rural community) affiliated with a large health system in the Southeastern United States. For the study outcome, ESI levels were grouped into three categories: 1-2 (highest acuity), 3, and 4-5 (lowest acuity). Multinomial logistic regression was used to compare ESI categories by patient race/ethnicity and sex jointly (referent = White males), adjusted for patient age, insurance status, ED arrival mode, chief complaint category, comorbidity score, time of day, day of week, and average ED wait time. RESULTS: We identified 186,840 eligible ED visits with 56,417 from the academic ED, 69,698 from the metropolitan community ED, and 60,725 from the rural community ED. Patient cohorts between EDs varied by patient age, race/ethnicity, and insurance status. The majority of patients were assigned ESI 3 in the academic and metropolitan community EDs (61% and 62%, respectively) whereas 47% were assigned ESI 3 in the rural community ED. In adjusted analyses, White females were less likely to be assigned ESI 1-2 compared to White males although both groups were roughly comparable in the assignment of ESI 4-5. Non-White and Hispanic females were generally least likely to be assigned ESI 1-2 in all EDs. Interactions between ED wait time and race/ethnicity-sex were not statistically significant. CONCLUSIONS: This retrospective study of adult ED patients revealed sex and race/ethnicity-based differences in ESI assignment, after accounting for age, clinical factors, and ED operating conditions. These disparities persisted across three different large EDs, highlighting the need for ongoing research to address inequities in ED triage decision-making and associated patient-centered outcomes.
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Etnicidade , Disparidades em Assistência à Saúde , Grupos Raciais , Triagem , Adulto , Feminino , Humanos , Masculino , Serviço Hospitalar de Emergência , Estudos Retrospectivos , Estados UnidosRESUMO
Six biomass carbon dots (BCDs) with adjustable emission from 450 to 680 nm under a single wavelength excitation were successfully synthesized from spinach via solvent control strategy. The obtained BCDs show blue, green, yellow, violet, pink, and red emission with high photoluminescence quantum yield (PLQY = 12.68 ~ 30.77%). Detailed characterizations disclose that the tunable-emission mechanism is caused by the synergistic effect of carbon conjugate and surface oxidation degree. Meanwhile, full-color photoluminescence BCDs/PVP powder and BCDs/PVP/PVA films were fabricated by utilizing the prepared BCDs combined with polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA), respectively, which presented excellent high-level information encryption application. Importantly, multi-color and white light-emitting diode (LED) with Commission Internationale de L' Eclairage (CIE) of blue (0.25, 0.29); green (0.25, 0.31); yellow (0.42, 0.45); red (0.52, 0.31); and white (0.32, 0.31) were achieved by only using our prepared BCDs. This work provides a valuable strategy of preparing multi-color BCDs using readily available biomass materials and paves a way for high-level information encryption and LED applications.
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OBJECTIVES: to understand the morphological characteristics of iliac crest and provide advice and assistance for jaw bone reconstruction with iliac bone flap by evaluating the thickness and curvature of iliac crest. MATERIALS AND METHODS: 100 patients who had taken Spiral CT of the Abdominal region before surgeries between 2020 and 2022 were included in this study. 3D reconstruction images of the iliac bones were created. 5 vertical planes perpendicular to the iliac crest were made every 2 cm along the centerline of the iliac crest (VP2 ~ VP10). On these vertical planes, 4 perpendicular lines were made every 1 cm along the long axis of the iliac crest (D1 ~ D4). The thicknesses at these sites, horizontal angle (HA) of iliac crest and the distance between inflection point and the central point of anterior superior iliac spine (DIA) were measured. RESULTS: The thickness of iliac bone decreased significantly from D1 ~ D4 on VP6 ~ VP10 and from VP2 ~ VP10 on D3 and D4 level (P<0.05). HA of iliac crests was 149.13 ± 6.92°, and DIA was 7.36 ± 1.01 cm. Iliac bone thickness, HA and DIA had very weak or weak correlation with patient's age, height and weight. CONCLUSIONS: The average thicknesses of iliac crest were decreased approximately from front to back, from top to bottom. The thickness and curvature of the iliac crest were difficult to predict by age, height and weight. CLINICAL RELEVANCE: Virtual surgical planning is recommended before jaw bone reconstruction surgery with iliac bone flap, and iliac crest process towards alveolar process might be a better choice.
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Ílio , Imageamento Tridimensional , Humanos , Ílio/transplante , Ílio/diagnóstico por imagem , Ílio/cirurgia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Imageamento Tridimensional/métodos , Tomografia Computadorizada Espiral , Idoso , Retalhos Cirúrgicos , Procedimentos de Cirurgia Plástica/métodos , Transplante Ósseo/métodosRESUMO
Vibrio fluvialis is an emerging foodborne pathogenic bacterium that can cause severe cholera-like diarrhea and various extraintestinal infections, posing challenges to public health and food safety worldwide. The arginine deiminase (ADI) pathway plays an important role in bacterial environmental adaptation and pathogenicity. However, the biological functions and regulatory mechanisms of the pathway in V. fluvialis remain unclear. In this study, we demonstrate that L-arginine upregulates the expression of the ADI gene cluster and promotes the growth of V. fluvialis. The ADI gene cluster, which we proved to be comprised of two operons, arcD and arcACB, significantly enhances the survival of V. fluvialis in acidic environments both in vitro (in culture medium and in macrophage) and in vivo (in mice). The mRNA level and reporter gene fusion analyses revealed that ArgR, a transcriptional factor, is necessary for the activation of both arcD and arcACB transcriptions. Bioinformatic analysis predicted the existence of multiple potential ArgR binding sites at the arcD and arcACB promoter regions that were further confirmed by electrophoretic mobility shift assay, DNase I footprinting, or point mutation analyses. Together, our study provides insights into the important role of the ArgR-ADI pathway in the survival of V. fluvialis under acidic conditions and the detailed molecular mechanism. These findings will deepen our understanding of how environmental changes and gene expression interact to facilitate bacterial adaptations and virulence.
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Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Hidrolases , Animais , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Camundongos , Hidrolases/metabolismo , Hidrolases/genética , Regiões Promotoras Genéticas , Óperon/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Vibrio/genética , Vibrio/metabolismo , Vibrio/patogenicidade , Arginina/metabolismo , Família Multigênica , Virulência/genética , Viabilidade MicrobianaRESUMO
BACKGROUND: In the present work, acute gastric ulcer models were constructed by administering hydrochloric acid/ethanol. The mice ingested white jade snail secretion (WJSS) through gastric infusion. Ulcer areas in gastric tissue were recorded, and malondialdehyde (MDA) and superoxide dismutase (SOD) were also measured. Notably, high-throughput 16S rDNA analysis of intestinal flora and determination of amino acid composition in feces were performed to understand the effect of WJSS on model mice. RESULTS: Compared with the control group, the ulcer area in the WJSS low-, medium- and high-concentration groups declined by 28.02%, 39.57% and 77.85%, respectively. MDA content decreased by 24.71%, 49.58% and 64.25%, and SOD relative enzyme activity fell by 28.19%, 43.37% and 9.60%, respectively. The amounts of amino acids in the low-, medium- and high-concentration groups were slightly lower, and probiotic bacteria such as Bacteroidetes and Lactobacillales increased in different-concentration WJSS groups. Adding WJSS contributes to the establishment of beneficial intestinal flora and the absorption of amino acids. CONCLUSION: Our results showed that WJSS has a beneficial effect on inhibiting hydrochloric acid-ethanolic gastric ulcers, suggesting that WJSS has excellent potential as a novel anti-ulcer agent. Combined with ulcer area, MDA content, SOD content, gut probiotics and other indicators, a high concentration of WJSS had the best protective effect on acute gastric ulcer. © 2023 Society of Chemical Industry.
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Antiulcerosos , Úlcera Gástrica , Camundongos , Animais , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/metabolismo , Antioxidantes/metabolismo , Ácido Clorídrico , Úlcera/tratamento farmacológico , Úlcera/metabolismo , Antiulcerosos/metabolismo , Antiulcerosos/farmacologia , Antiulcerosos/uso terapêutico , Etanol/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Extratos Vegetais/metabolismo , Aminoácidos/metabolismo , Mucosa Gástrica/metabolismoRESUMO
OBJECTIVE: To explore the ameliorative effect of yeast extract(YE) on the inflammatory response of human hepatoma cells(HepG2) induced by ethyl alcohol(EtOH) and lipopolysaccharide(LPS), and further explore the potential molecular mechanism based on Toll-like receptor 4(TLR4)/nuclear factor kappa B(NF-κB) signaling pathway. METHODS: HepG2 cells were induced by 50 mmol/L EtOH and 1 µg/mL LPS combined with YE intervention. The expression level of inflammatory cytokines was detected by ELISA. The expression level of TLR4 and the nuclear translocation of NF-κB were detected by immunofluorescence staining. The expression levels of TLR4, NF-κB, phospho-NF-κB-P65(P-NF-κB-p65), nucleus-phospho-NF-κB-p65(N-P-NF-κB-p65), tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), and interleukin-1ß(IL-1ß) were detected by Western blot. RESULTS: Compared with the control group, the cells in EtOH+LPS group produced a large number of inflammatory factors and had a significant inflammatory response. YE intervention significantly alleviated EtOH+LPS induced hepatocyte inflammatory response. Further molecular mechanism studies showed that YE significantly reduced TLR4 expression level and inhibited NF-κB nuclear translocation in hepatocytes. CONCLUSION: YE can effectively inhibit the inflammatory response of HepG2 cells induced by EtOH and LPS, and its molecular mechanism may be related to the down-regulation of TLR4/NF-κB pathway.
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Lipopolissacarídeos , NF-kappa B , Humanos , Células Hep G2 , Receptor 4 Toll-Like , Etanol/toxicidade , Interleucina-1beta , Interleucina-6 , Fator de Necrose Tumoral alfaRESUMO
While all-inorganic halide perovskites (iHPs) are promising photovoltaic materials, the associated water sensitivity of iHPs calls for stringent humidity control to reach satisfactory photovoltaic efficiencies. Herein, we report a moisture-insensitive perovskite formation route under ambient air for CsPbI2 Br-based iHPs via cesium cyclopropane acids (C3 ) as a compound introducer. With this approach, appreciably enhanced crystallization quality and moisture tolerance of CsPbI2 Br are attained. The improvements are attributed to the modified evaporation enthalpy of the volatile side product of DMA-acid initiated by Cs-acids. As such, the water-involving reaction is directed toward the DMA-acids, leaving the target CsPbI2 Br perovskites insensitive to ambient humidity. We highlight that by controlling the C3 concentration, the dependence of power conversion efficiency (PCE) in CsPbI2 Br devices on the humidity level during perovskite film formation becomes favorably weakened, with the PCEs remaining relatively high (>15 %) associated with improved device stability for RH levels changed from 25 % to 65 %. The champion solar cells yield an impressive PCE exceeding 17 %, showing small degradations (<10 %) for 2000â hours of shell storage and 300â hours of 85/85 (temperature/humidity) tests. The demonstrated C3 -based strategy provides an enabler for improving the long-sought moisture-stability of iHPs toward high photovoltaic device performance.
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Lithium polysulfides (LiPSs) are pivotal intermediates involved in all the cathodic reactions in lithium-sulfur (Li-S) batteries. Elucidating the solvation structure of LiPSs is the first step for rational design of electrolyte and improving Li-S battery performances. Herein, we investigate the solvation structure of LiPSs and find that Li salt anions tend to enter the first solvation sheath of LiPSs and form contact ion pairs in electrolyte. The anion-involved solvation structure of LiPSs significantly influences the intrinsic kinetics of the sulfur redox reactions. In particular, the LiPS solvation structure modified by lithium bis(fluorosulfonyl)imide endows Li-S batteries with reduced polarization and enhanced rate performances under high sulfur areal loading and lean electrolyte volume conditions. This work updates the fundamental understanding of the solvation chemistry of LiPSs and highlights electrolyte engineering for promoting the performances of Li-S batteries.
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Lithium-sulfur (Li-S) batteries afford great promise on achieving practical high energy density beyond lithium-ion batteries. Lean-electrolyte conditions constitute the prerequisite for achieving high-energy-density Li-S batteries but inevitably deteriorates battery performances, especially the sulfur cathode kinetics. Herein, the polarizations of the sulfur cathode are systematically decoupled to identify the key kinetic limiting factor in lean-electrolyte Li-S batteries. Concretely, an electrochemical impedance spectroscopy combined galvanostatic intermittent titration technique method is developed to decouple the cathodic polarizations into activation, concentration, and ohmic parts. Therein, activation polarization during lithium sulfide nucleation emerges as the dominant polarization as the electrolyte-to-sulfur ratio (E/S ratio) decreases, and the sluggish interfacial charge transfer kinetics is identified as the main reason for degraded cell performances under lean-electrolyte conditions. Accordingly, a lithium bis(fluorosulfonyl)imide electrolyte is proposed to decrease activation polarization, and Li-S batteries adopting this electrolyte provide a discharge capacity of 985 mAh g-1 under a low E/S ratio of 4 µL mg-1 at 0.2 C. This work identifies the key kinetic limiting factor of lean-electrolyte Li-S batteries and provides guidance on designing rational promotion strategies to achieve advanced Li-S batteries.
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BACKGROUND: Portal vein tumour thrombus (PVTT) is the main pathway of HCC intrahepatic metastasis and is responsible for the poor prognosis of patients with HCC. However, the molecular mechanisms underlying PVTT vascular metastases have not been fully elucidated. METHODS: NDRG1 expression was assessed by immunohistochemistry and immunoblotting in clinical specimens obtained from curative surgery. The functional relevance of NDRG1 was evaluated using sphere formation and animal models of tumorigenicity and metastasis. The relationship between NDRG1 and EpCAM was explored using molecular biological techniques. RESULTS: NDRG1 protein was upregulated in HCC samples compared to non-tumorous tissues. Furthermore, NDRG1 expression was enhanced in the PVTT samples. Our functional study showed that NDRG1 was required for the self-renewal of tumour-initiating/cancer stem cells (CSCs). In addition, NDRG1 knockdown inhibited the proliferation and migration of PVTT-1 cells in vitro and in vivo. NDRG1 was found to stabilise the functional tumour-initiating cell marker EpCAM through protein-protein interactions and inhibition of EpCAM ubiquitination. CONCLUSION: Our findings suggest that NDRG1 enhances CSCs expansion, PVTT formation and growth capability through the regulation of EpCAM stability. NDRG1 may be a promising target for the treatment of patients with HCC and PVTT.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Trombose , Animais , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Molécula de Adesão da Célula Epitelial/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Células-Tronco Neoplásicas/patologia , Linhagem Celular TumoralRESUMO
The essential role of epigenetic modification in the pathogenesis of a series of cancers have gradually been recognized. Histone deacetylase (HDACs), as well-known epigenetic modulators, are responsible for DNA repair, cell proliferation, differentiation, apoptosis and angiogenesis. Studies have shown that aberrant expression of HDACs is found in many cancer types. Thus, inhibition of HDACs has provided a promising therapeutic approach alternative for these patients. Since HDAC inhibitor (HDACi) vorinostat was first approved by the Food and Drug Administration (FDA) for treating cutaneous T-cell lymphoma (CTCL) in 2006, the combination of HDAC inhibitors with other molecules such as chemotherapeutic drugs has drawn much attention in current cancer treatment, especially in hematological malignancies therapy. Up to now, there have been more than twenty HDAC inhibitors investigated in clinic trials with five approvals being achieved. Indeed, Histone deacetylase inhibitors promote or enhance several different anticancer mechanisms and therefore are in evidence as potential antileukemia agents. In this review, we will focus on possible mechanisms by how HDAC inhibitors exert therapeutic benefit and their clinical utility in leukemia.