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Human DNA topoisomerase 1 (Top1) is a crucial enzyme responsible for alleviating torsional stress on DNA during transcription and replication, thereby maintaining genome stability. Previous researches had found that non-working Top1 interacted extensively with chromosomal DNA in human cells. However, the reason for its retention on chromosomal DNA remained unclear. In this study, we discovered a close association between Top1 and chromosomal DNA, specifically linked to the presence of G-quadruplex (G4) structures. G4 structures, formed during transcription, trap Top1 and hinder its ability to relax neighboring DNAs. Disruption of the Top1-G4 interaction using G4 ligand relieved the inhibitory effect of G4 on Top1 activity, resulting in a further reduction of R-loop levels in cells. Additionally, the activation of Top1 through the use of a G4 ligand enhanced the toxicity of Top1 inhibitors towards cancer cells. Our study uncovers a negative regulation mechanism of human Top1 and highlights a novel pathway for activating Top1.
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DNA Topoisomerases Tipo I , Quadruplex G , Transcrição Gênica , Humanos , DNA/química , Replicação do DNA , DNA Topoisomerases Tipo I/metabolismo , Ligantes , Inibidores da Topoisomerase I/farmacologiaRESUMO
CpcL-phycobilisomes (CpcL-PBSs) are a reduced type of phycobilisome (PBS) found in several cyanobacteria. They lack the traditional PBS terminal energy emitters, but still show the characteristic red-shifted fluorescence at ~670 nm. We established a method of assembling in vitro a rod-membrane linker protein, CpcL, with phycocyanin, generating complexes with the red-shifted spectral features of CpcL-PBSs. The red-shift arises from the interaction of a conserved key glutamine, Q57 of CpcL in Synechocystis sp. PCC 6803, with a single phycocyanobilin chromophore of trimeric phycocyanin at one of the three ß82-sites. This chromophore is the terminal energy acceptor of CpcL-PBSs and donor to the photosystem(s). This mechanism also operates in PBSs from Acaryochloris marina MBIC11017. We then generated multichromic complexes harvesting light over nearly the complete visible range via the replacement of phycocyanobilin chromophores at sites α84 and ß153 of phycocyanins by phycoerythrobilin and/or phycourobilin. The results demonstrate the rational design of biliprotein-based light-harvesting elements by engineering CpcL and phycocyanins, which broadens the light-harvesting range and accordingly improves the light-harvesting capacity and may be potentially applied in solar energy harvesting.
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Proteínas de Bactérias , Ficobilinas , Ficobilissomas , Ficocianina , Synechocystis , Ficobilissomas/metabolismo , Ficocianina/metabolismo , Ficocianina/química , Synechocystis/metabolismo , Proteínas de Bactérias/metabolismo , Ficobilinas/metabolismo , Ficobilinas/química , Cianobactérias/metabolismoRESUMO
Cold and saline-alkali stress are frequently encountered by plants, and they often occur simultaneously in saline-alkali soils at mid to high latitudes, constraining forage crop distribution and production. However, the mechanisms by which forage crops respond to the combination of cold and saline-alkali stress remain unknown. Alfalfa (Medicago sativa L.) is one of the most essential forage grasses in the world. In this study, we analyzed the complex response mechanisms of two alfalfa species (Zhaodong [ZD] and Blue Moon [BM]) to combined cold and saline-alkali stress using multi-omics. The results revealed that ZD had a greater ability to tolerate combined stress than BM. The tricarboxylic acid cycles of the two varieties responded positively to the combined stress, with ZD accumulating more sugars, amino acids, and jasmonic acid. The gene expression and flavonoid content of the flavonoid biosynthesis pathway were significantly different between the two varieties. Weighted gene co-expression network analysis and co-expression network analysis based on RNA-Seq data suggested that the MsMYB12 gene may respond to combined stress by regulating the flavonoid biosynthesis pathway. MsMYB12 can directly bind to the promoter of MsFLS13 and promote its expression. Moreover, MsFLS13 overexpression can enhance flavonol accumulation and antioxidant capacity, which can improve combined stress tolerance. These findings provide new insights into improving alfalfa resistance to combined cold and saline-alkali stress, showing that flavonoids are essential for plant resistance to combined stresses, and provide theoretical guidance for future breeding programs.
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Regulação da Expressão Gênica de Plantas , Medicago sativa , Metabolômica , Medicago sativa/genética , Medicago sativa/fisiologia , Medicago sativa/metabolismo , Perfilação da Expressão Gênica , Estresse Fisiológico , Álcalis , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma , Temperatura BaixaRESUMO
BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.
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Anticorpos Monoclonais Humanizados , Quimiorradioterapia , Quimioterapia de Indução , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamento farmacológico , Adulto , China/epidemiologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimiorradioterapia/métodos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Idoso , Cisplatino/uso terapêutico , Cisplatino/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gencitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Desoxicitidina/administração & dosagem , Adulto Jovem , Adolescente , Intervalo Livre de ProgressãoRESUMO
BACKGROUND: The association between the TDRD6 variants and human infertility remains unclear, as only one homozygous missense variant of TDRD6 was found to be associated with oligoasthenoteratozoospermia (OAT). METHODS: Whole-exome sequencing and Sanger sequencing were employed to identify potential pathogenic variants of TDRD6 in infertile men. Histology, immunofluorescence, immunoblotting and ultrastructural analyses were conducted to clarify the structural and functional abnormalities of sperm in mutated patients. Tdrd6-knockout mice were generated using the CRISPR-Cas9 system. Total RNA-seq and single-cell RNA-seq (scRNA-seq) analyses were used to elucidate the underlying molecular mechanisms, followed by validation through quantitative RT-PCR and immunostaining. Intracytoplasmic sperm injection (ICSI) was also used to assess the efficacy of clinical treatment. RESULTS: Bi-allelic TDRD6 variants were identified in five unrelated Chinese individuals with OAT, including homozygous loss-of-function variants in two consanguineous families. Notably, besides reduced concentrations and impaired motility, a significant occurrence of acrosomal hypoplasia was detected in multiple spermatozoa among five patients. Using the Tdrd6-deficient mice, we further elucidate the pivotal role of TDRD6 in spermiogenesis and acrosome identified. In addition, the mislocalisation of crucial chromatoid body components DDX4 (MVH) and UPF1 was also observed in round spermatids from patients harbouring TDRD6 variants. ScRNA-seq analysis of germ cells from a patient with TDRD6 variants revealed that TDRD6 regulates mRNA metabolism processes involved in spermatid differentiation and cytoplasmic translation. CONCLUSION: Our findings strongly suggest that TDRD6 plays a conserved role in spermiogenesis and confirms the causal relationship between TDRD6 variants and human OAT. Additionally, this study highlights the unfavourable ICSI outcomes in individuals with bi-allelic TDRD6 variants, providing insights for potential clinical treatment strategies.
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Alelos , Astenozoospermia , Sequenciamento do Exoma , Camundongos Knockout , Espermatogênese , Adulto , Animais , Humanos , Masculino , Camundongos , Acrossomo/patologia , Astenozoospermia/genética , Astenozoospermia/patologia , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Oligospermia/genética , Oligospermia/patologia , Linhagem , Injeções de Esperma Intracitoplásmicas , Espermatogênese/genética , Espermatozoides/patologia , Espermatozoides/metabolismoRESUMO
Development of mRNA therapeutics necessitates targeted delivery technology, while the clinically advanced lipid nanoparticles face difficulty for extrahepatic delivery. Herein, we design highly branched poly(ß-amino ester)s (HPAEs) for efficacious organ-selective mRNA delivery through tailoring their chemical compositions and topological structures. Using an "A2+B3+C2" Michael addition platform, a combinatorial library of 219 HPAEs with varied backbone structures, terminal groups, and branching degrees are synthesized. The branched topological structures of HPAEs provide enhanced serum resistance and significantly higher mRNA expression in vivo. The terminal amine structures of HPAEs determine the organ-selectivity of mRNA delivery following systemic administration: morpholine facilitates liver targeting, ethylenediamine favors spleen delivery, while methylpentane enables mRNA delivery to the liver, spleen, and lungs simultaneously. This study represents a comprehensive exploration of the structure-activity relationship governing both the efficiency and organ-selectivity of mRNA delivery by HPAEs, suggesting promising candidates for treating various organ-related diseases.
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Polímeros , RNA Mensageiro , RNA Mensageiro/genética , Animais , Humanos , Polímeros/química , Camundongos , Nanopartículas/química , Fígado/metabolismo , Baço/metabolismo , Técnicas de Transferência de Genes , Pulmão/metabolismoRESUMO
Biological materials exhibit fascinating mechanical properties for intricate interactions at multiple interfaces to combine superb toughness with wondrous strength and stiffness. Recently, strong interlayer entanglement has emerged to replicate the powerful dissipation of natural proteins and alleviate the conflict between strength and toughness. However, designing intricate interactions in a strong entanglement network needs to be further explored. Here, we modulate interlayer entanglement by introducing multiple interactions, including hydrogen and ionic bonding, and achieve ultrahigh mechanical performance of graphene-based nacre fibers. Two essential modulating trends are directed. One is modulating dynamic hydrogen bonding to improve the strength and toughness up to 1.58 GPa and 52 MJ/m3, simultaneously. The other is tailoring ionic coordinating bonding to raise the strength and stiffness, reaching 2.3 and 253 GPa. Modulating various interactions within robust entanglement provides an effective approach to extend performance limits of bioinspired nacre and optimize multiscale interfaces in diverse composites.
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BACKGROUND: There are two major genetic types of Epstein-Barr Virus (EBV): type 1 (EBV-1) and type 2 (EBV-2). EBV functions by manipulating gene expression in host B cells, using virus-encoded gene regulatory proteins including Epstein-Barr Nuclear Antigen 2 (EBNA2). While type 1 EBNA2 is known to interact with human transcription factors (hTFs) such as RBPJ, EBF1, and SPI1 (PU.1), type 2 EBNA2 shares only ~ 50% amino acid identity with type 1 and thus may have distinct binding partners, human genome binding locations, and functions. RESULTS: In this study, we examined genome-wide EBNA2 binding in EBV-1 and EBV-2 transformed human B cells to identify shared and unique EBNA2 interactions with the human genome, revealing thousands of type-specific EBNA2 ChIP-seq peaks. Computational predictions based on hTF motifs and subsequent ChIP-seq experiments revealed that both type 1 and 2 EBNA2 co-occupy the genome with SPI1 and AP-1 (BATF and JUNB) hTFs. However, type 1 EBNA2 showed preferential co-occupancy with EBF1, and type 2 EBNA2 preferred RBPJ. These differences in hTF co-occupancy revealed possible mechanisms underlying type-specific gene expression of known EBNA2 human target genes: MYC (shared), CXCR7 (type 1 specific), and CD21 (type 2 specific). Both type 1 and 2 EBNA2 binding events were enriched at systemic lupus erythematosus (SLE) and multiple sclerosis (MS) risk loci, while primary biliary cholangitis (PBC) risk loci were specifically enriched for type 2 peaks. CONCLUSIONS: This study reveals extensive type-specific EBNA2 interactions with the human genome, possible differences in EBNA2 interaction partners, and a possible new role for type 2 EBNA2 in autoimmune disorders. Our results highlight the importance of considering EBV type in the control of human gene expression and disease-related investigations.
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Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Humanos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Genoma Humano , Antígenos Nucleares do Vírus Epstein-Barr/genética , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Proteínas Virais/genética , Fatores de Transcrição/metabolismoRESUMO
Mesenchymal stem cells (MSCs) display unique homing and immunosuppression features which make them promising candidates for cell therapy in inflammatory disorders. It is known that C-X-C chemokine receptor type 4 (CXCR4, also known as CD184) is a critical receptor implicated in MSCs migration, and the protein programmed death ligand-1 (PD-L1) is involved in MSC's immunosuppression. However, it remains unclear how the molecular mechanisms regulate PD-L1 expression for migration and immunosuppression of MSCs under the inflammatory microenvironment. In this article, we used the human adipose-derived mesenchymal stem cells (hADMSCs) treated with lipopolysaccharide (LPS) as an in vitro inflammatory model to explore the roles of PD-L1 on the migration and immunosuppression of MSC. Our results demonstrate that in hADMSCs, LPS significantly increased PD-L1 expression, which mediated the migration of the LPS-treated hADMSCs via CXCR4. In addition, we found that the increased PD-L1 expression in the LPS-treated hADMSCs inhibited B cell proliferation and immunoglobulin G secretion through nuclear factor-κB. Our study suggests that the PD-L1 plays critical roles in the homing and immunosuppression of MSCs which are a promising cell therapy to treat inflammatory diseases.
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Antígeno B7-H1 , Células-Tronco Mesenquimais , Humanos , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Células-Tronco Mesenquimais/metabolismo , NF-kappa B/metabolismo , Transdução de SinaisRESUMO
BN/CC isosterism is an effective strategy to build hybrid functional molecules with unique properties. In contrast to the alkynyl iminium salts derived from cyclic (alkyl)(amino)carbenes (CAACs) that feature only one reversible reduction wave, the isoelectronic cationic CAAC-iminoboryl adducts could be singly and doubly reduced smoothly. Both the resultant neutral radical and anionic azaborataallenes bear NBC-mixed allenic structures. The former radical has a high spin-density of 0.55e at CCAAC carbon, yet exhibits formal boron-centered radical reactivity. The latter azaborataallenes feature the nucleophilic CCAAC center and polar N(δ-)âB(δ+)âC(δ-) unit, and readily undergo nucleophilic substitution, isocyanide insertion, dipolar addition and cycloaddition reactions etc. The N-substituents have been shown to have a significant influence on the solid-state structure, thermal stability, and reactivity of azaborataallenes. This work showcases the allenic BN-unsaturated species as versatile building blocks in organic synthesis.
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Since the large-scale outbreak of porcine epidemic diarrhoea (PED) in 2010, caused by the genotype 2 (G2) variant of the porcine epidemic diarrhoea virus (PEDV), pig farms in China, even those vaccinated with the G2b vaccine, have experienced infections from the G2a variant, leading to significant economic losses. This study successfully isolated the G2a strain DY2020 from positive small intestine contents (SICs) by blind passage on Vero cells for four generations. The SICs were taken from Daye, Hubei Province, China. The biological characteristics were identified by indirect immunofluorescence assay (IFA) and transmission electron microscopy (TEM). The growth kinetics of the strain on Vero cells were detected by TCID50, and the virus titre could reach 107.35 TCID50 ml-1 (SD: 5.07×106). The pathogenicity towards colostrum-deprived piglets was conducted by assessing faecal viral shedding, morphometric analysis of intestinal lesions, and immunohistochemical staining. The results showed that DY2020 was highly virulent to colostrum-deprived piglets, with severe watery diarrhoea and other clinical symptoms appeared at 6 h post-infection (h p.i.), and all died within 30 h. Pathological tissue examination results showed that the lesions mainly occurred in the intestines of piglets, causing pathological changes such as shortening of intestinal villi. In summary, the discovery of the G2a strain DY2020 in this study is of great significance for understanding Hubei PEDV and provides an important theoretical basis for the development of new efficient PEDV vaccines.
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Vírus da Diarreia Epidêmica Suína , Chlorocebus aethiops , Animais , Suínos , Virulência , Células Vero , China , Diarreia/veterináriaRESUMO
This study investigates the role of USP47, a deubiquitinating enzyme, in the tumor microenvironment and its impact on antitumor immune responses. Analysis of TCGA database revealed distinct expression patterns of USP47 in various tumor tissues and normal tissues. Prostate adenocarcinoma showed significant downregulation of USP47 compared to normal tissue. Correlation analysis demonstrated a positive association between USP47 expression levels and infiltrating CD8+ T cells, neutrophils, and macrophages, while showing a negative correlation with NKT cells. Furthermore, using Usp47 knockout mice, we observed a slower tumor growth rate and reduced tumor burden. The absence of USP47 led to increased infiltration of immune cells, including neutrophils, macrophages, NK cells, NKT cells, and T cells. Additionally, USP47 deficiency resulted in enhanced activation of cytotoxic T lymphocytes (CTLs) and altered T cell subsets within the tumor microenvironment. These findings suggest that USP47 plays a critical role in modulating the tumor microenvironment and promoting antitumor immune responses, highlighting its potential as a therapeutic target in prostate cancer.
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Linfócitos do Interstício Tumoral , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Linhagem Celular Tumoral , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Microambiente TumoralRESUMO
BACKGROUND: The myeloblastosis (MYB) transcription factor (TF) family is one of the largest and most important TF families in plants, playing an important role in a life cycle and abiotic stress. RESULTS: In this study, 268 Avena sativa MYB (AsMYB) TFs from Avena sativa were identified and named according to their order of location on the chromosomes, respectively. Phylogenetic analysis of the AsMYB and Arabidopsis MYB proteins were performed to determine their homology, the AsMYB1R proteins were classified into 5 subgroups, and the AsMYB2R proteins were classified into 34 subgroups. The conserved domains and gene structure were highly conserved among the subgroups. Eight differentially expressed AsMYB genes were screened in the transcriptome of transcriptional data and validated through RT-qPCR. Three genes in AsMYB2R subgroup, which are related to the shortened growth period, stomatal closure, and nutrient and water transport by PEG-induced drought stress, were investigated in more details. The AsMYB1R subgroup genes LHY and REV 1, together with GST, regulate ROS homeostasis to ensure ROS signal transduction and scavenge excess ROS to avoid oxidative damage. CONCLUSION: The results of this study confirmed that the AsMYB TFs family is involved in the homeostatic regulation of ROS under drought stress. This lays the foundation for further investigating the involvement of the AsMYB TFs family in regulating A. sativa drought response mechanisms.
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Avena , Secas , Homeostase , Filogenia , Proteínas de Plantas , Espécies Reativas de Oxigênio , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Avena/genética , Avena/metabolismo , Regulação da Expressão Gênica de Plantas , Polietilenoglicóis/farmacologia , Família Multigênica , Estresse Fisiológico/genética , Estudo de Associação Genômica Ampla , Genoma de PlantaRESUMO
INTRODUCTION: To evaluate the effect of Embrella, a novel-designed colonoscopic distal attachment, on adenoma detection rate (ADR) and adenoma per colonoscopy (APC), compared with standard colonoscopy in routine practice. METHODS: All consecutive participants who underwent routine colonoscopic examinations at 3 endoscopy centers in China were enrolled. Participants were randomly assigned in a 1:1 ratio to the Embrella-assisted colonoscopy (EAC) or standard colonoscopy (SC) groups. ADR, APC, inspection time, pain scores, and adverse events were recorded. RESULTS: Overall, 1,179 participants were randomized into the EAC (n = 593) and SC groups (n = 586). EAC increased the overall ADR from 24.6% to 34.2% ( P < 0.001) and improved APC from 0.44 to 0.64 ( P = 0.002). Subgroup analyses indicated that EAC significantly improved ADR for adenomas < 10 mm (13.8% vs 8.5%, P = 0.004 for 5-9 mm and 27.0% vs 17.2%, P < 0.001 for < 5 mm), nonpedunculated adenomas (26.6% vs 18.8%, P < 0.001), and adenomas in the transverse (10.8% vs 6.1%, P = 0.004) and left colon (21.6% vs 13.7%, P < 0.001). APC in the subgroup analyses was consistent with ADR. The mean inspection time was shorter with EAC (6.52 vs 6.68 minutes, P = 0.046), with no significant impact on participants' pain scores ( P = 0.377). Moreover, no EAC-related adverse events occurred. DISCUSSION: EAC significantly increased ADR and APC compared with SC, particularly for adenomas <10 mm, nonpedunculated adenomas, and adenomas in the transverse and left colon.
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High-salinity wastewater treatment is perceived as a global water resource recycling challenge that must be addressed to achieve zero discharge. Monovalent/divalent salt separation using membrane technology provides a promising strategy for sulfate removal from chlor-alkali brine. However, existing desalination membranes often show low water permeance and insufficient ion selectivity. Herein, an aminal-linked covalent organic framework (COF) membrane featuring a regular long-range pore size of 7 Å and achieving superior ion selectivity is reported, in which a uniform COF layer with subnanosized channels is assembled by the chemical splicing of 1,4-phthalaldehyde (TPA)-piperazine (PZ) COF through an amidation reaction with trimesoyl chloride (TMC). The chemically spliced TPA-PZ (sTPA-PZ) membrane maintains an inherent pore structure and exhibits a water permeance of 13.1 L m-2 h-1 bar-1, a Na2SO4 rejection of 99.1%, and a Cl-/SO4 2- separation factor of 66 for mixed-salt separation, which outperforms all state-of-the-art COF-based membranes reported. Furthermore, the single-stage treatment of NaCl/Na2SO4 mixed-salt separation achieves a high NaCl purity of above 95% and a recovery rate of ≈60%, offering great potential for industrial application in monovalent/divalent salt separation and wastewater resource utilization. Therefore, the aminal-linked COF membrane developed in this work provides a new research avenue for designing smart/advanced membrane materials for angstrom-scale separations.
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Upgrading thermosetting polymer waste and harvesting unwanted electromagnetic energy are of great significance in solving environmental pollution and energy shortage problems. Herein, inspired by the glass-blowing art, a spontaneous, controllable, and scalable strategy is proposed to prepare hollow carbon materials by inner blowing and outside blocking. Specifically, hierarchically neuron-like hollow carbon materials (HCMSs) with various sizes are fabricated from melamine-formaldehyde sponge (MS) waste. Benefiting from the synergistic of the hollow "cell body" and the connected "protrusions" networks, HCMSs reveal superior electromagnetic absorption performance with a strong reflection loss of -54.9 dB, electromagnetic-heat conversion ability with a high conversion efficiency of 34.4%, and efficient energy storage performance in supercapacitor. Furthermore, a multifunctional device integrating electromagnetic-heat-electrical energy conversion is designed, and its feasibility is proved by experiments and theoretical calculations. The integrated device reveals an output voltage of 34.5 mV and a maximum output power of 0.89 µW with electromagnetic radiation for 60 s. This work provides a novel solution to recycle polymer waste, electromagnetic energy, and unwanted thermal energy.
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Polyolefin separators are the most commonly used separators for lithium batteries; however, they tend to shrink when heated, and their Li+ transference number (t Li +) is low. Metal-organic frameworks (MOFs) are expected to solve the above problems due to their high thermal stability, abundant pore structure, and open metal sites. However, it is difficult to prepare high-porosity MOF-based membranes by conventional membrane preparation methods. In this study, a high-porosity free-standing MOF-based safety separator, denoted the BCM separator, is prepared through a nano-interfacial supramolecular adhesion strategy. The BCM separator has a large specific surface area (450.22 m2 g-1) and porosity (62.0%), a high electrolyte uptake (475 wt%), and can maintain its morphology at 200 °C. The ionic conductivity and t Li + of the BCM separator are 1.97 and 0.72 mS cm-1, respectively. Li//LiFePO4 cells with BCM separators have a capacity retention rate of 95.07% after 1100 cycles at 5 C, a stable high-temperature cycling performance of 300 cycles at 80 °C, and good capacity retention at -40 °C. Li//NCM811 cells with BCM separators exhibit significantly improved rate performance and cycling performance. Pouch cells with BCM separators can work at 120 °C and have good safety at high temperature.
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BACKGROUND: The global cellular landscape of the tumor microenvironment (TME) combining primary and metastatic liver tumors has not been comprehensively characterized. METHODS: Based on the scRNA-seq and spatial transcriptomic data of non-tumor liver tissues (NTs), primary liver tumors (PTs) and metastatic liver tumors (MTs), we performed the tissue preference, trajectory reconstruction, transcription factor activity inference, cell-cell interaction and cellular deconvolution analyses to construct a comprehensive cellular landscape of liver tumors. RESULTS: Our analyses depicted the heterogeneous cellular ecosystems in NTs, PTs and MTs. The activated memory B cells and effector T cells were shown to gradually shift to inhibitory B cells, regulatory or exhausted T cells in liver tumors, especially in MTs. Among them, we characterized a unique group of TCF7+ CD8+ memory T cells specifically enriched in MTs that could differentiate into exhausted T cells likely driven by the p38 MAPK signaling. With regard to myeloid cells, the liver-resident macrophages and inflammatory monocyte/macrophages were markedly replaced by tumor-associated macrophages (TAMs), with TREM2+ and UBE2C+ TAMs enriched in PTs, while SPP1+ and WDR45B+ TAMs in MTs. We further showed that the newly identified WDR45B+ TAMs exhibit an M2-like polarization and are associated with adverse prognosis in patients with liver metastases. Additionally, we addressed that endothelial cells display higher immune tolerance and angiogenesis capacity, and provided evidence for the source of the mesenchymal transformation of fibroblasts in tumors. Finally, the malignant hepatocytes and fibroblasts were prioritized as the pivotal cell populations in shaping the microenvironments of PTs and MTs, respectively. Notably, validation analyses by using spatial or bulk transcriptomic data in clinical cohorts concordantly emphasized the clinical significance of these findings. CONCLUSIONS: This study defines the ontological and functional heterogeneities in cellular ecosystems of primary and metastatic liver tumors, providing a foundation for future investigation of the underlying cellular mechanisms.
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Células Endoteliais , Neoplasias Hepáticas , Humanos , Ecossistema , Neoplasias Hepáticas/genética , Perfilação da Expressão Gênica , Microambiente TumoralRESUMO
PURPOSE: This study aims to develop and evaluate a novel cardiovascular MR sequence, MyoFold, designed for the simultaneous quantifications of myocardial tissue composition and wall motion. METHODS: MyoFold is designed as a 2D single breathing-holding sequence, integrating joint T1/T2 mapping and cine imaging. The sequence uses a 2-fold accelerated balanced SSFP (bSSFP) for data readout and incorporates electrocardiogram synchronization to align with the cardiac cycle. MyoFold initially acquires six single-shot inversion-recovery images, completed during the diastole of six successive heartbeats. T2 preparation (T2-prep) is applied to introduce T2 weightings for the last three images. Subsequently, over the following six heartbeats, segmented bSSFP is performed for the movie of the entire cardiac cycle, synchronized with an electrocardiogram. A neural network trained using numerical simulations of MyoFold is used for T1 and T2 calculations. MyoFold was validated through phantom and in vivo experiments, with comparisons made against MOLLI, SASHA, T2-prep bSSFP, and the conventional cine. RESULTS: In phantom studies, MyoFold exhibited a 10% overestimation in T1 measurements, whereas T2 measurements demonstrated high accuracy. In vivo experiments revealed that MyoFold T1 had comparable accuracy to SASHA and precision similar to MOLLI. MyoFold demonstrated good agreement with T2-prep bSSFP in myocardial T2 measurements. No significant differences were observed in the quantification of left-ventricle wall thickness and function between MyoFold and the conventional cine. CONCLUSION: MyoFold presents as a rapid, simple, and multitasking approach for quantitative cardiovascular MR examinations, offering simultaneous assessment of tissue composition and wall motion. The sequence's multitasking capabilities make it a promising tool for comprehensive cardiac evaluations in clinical settings.
Assuntos
Coração , Imagem Cinética por Ressonância Magnética , Imagens de Fantasmas , Adulto , Feminino , Humanos , Masculino , Algoritmos , Eletrocardiografia , Coração/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Miocárdio , Reprodutibilidade dos TestesRESUMO
Preterm infants face a high risk of various complications, and their gut microbiota plays a pivotal role in health. Delivery modes have been reported to affect the development of gut microbiota in term infants, but its impact on preterm infants remains unclear. Here, we collected fecal samples from 30 preterm infants at five-time points within the first four weeks of life. Employing 16â¯S rRNA sequencing, principal coordinates analysis, the analysis of similarities, and the Wilcoxon rank-sum test, we examined the top dominant phyla and genera, the temporal changes in specific taxa abundance, and their relationship with delivery modes, such as Escherichia-Shigella and Enterococcus based on vaginal delivery and Pluralibacter related to cesarean section. Moreover, we identified particular bacteria, such as Taonella, Patulibacter, and others, whose proportions fluctuated among preterm infants born via different delivery modes at varying time points, as well as the microbiota types and functions. These results indicated the influence of delivery mode on the composition and function of the preterm infant gut microbiota. Importantly, these effects are time-dependent during the early stages of life. These insights shed light on the pivotal role of delivery mode in shaping the gut microbiota of preterm infants and have significant clinical implications for their care and management.