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Clear cell renal cell carcinoma (ccRCC) is characterized by near-universal loss of the short arm of chromosome 3, deleting several tumor suppressor genes. We analyzed whole genomes from 95 biopsies across 33 patients with clear cell renal cell carcinoma. We find hotspots of point mutations in the 5' UTR of TERT, targeting a MYC-MAX-MAD1 repressor associated with telomere lengthening. The most common structural abnormality generates simultaneous 3p loss and 5q gain (36% patients), typically through chromothripsis. This event occurs in childhood or adolescence, generally as the initiating event that precedes emergence of the tumor's most recent common ancestor by years to decades. Similar genomic changes drive inherited ccRCC. Modeling differences in age incidence between inherited and sporadic cancers suggests that the number of cells with 3p loss capable of initiating sporadic tumors is no more than a few hundred. Early development of ccRCC follows well-defined evolutionary trajectories, offering opportunity for early intervention.
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Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Progressão da Doença , Neoplasias Renais/genética , Neoplasias Renais/patologia , Mutação , Regiões 5' não Traduzidas , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 3 , Cromossomos Humanos Par 5 , Feminino , Dosagem de Genes , Genoma Humano , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Telomerase/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genéticaRESUMO
The evolutionary features of clear-cell renal cell carcinoma (ccRCC) have not been systematically studied to date. We analyzed 1,206 primary tumor regions from 101 patients recruited into the multi-center prospective study, TRACERx Renal. We observe up to 30 driver events per tumor and show that subclonal diversification is associated with known prognostic parameters. By resolving the patterns of driver event ordering, co-occurrence, and mutual exclusivity at clone level, we show the deterministic nature of clonal evolution. ccRCC can be grouped into seven evolutionary subtypes, ranging from tumors characterized by early fixation of multiple mutational and copy number drivers and rapid metastases to highly branched tumors with >10 subclonal drivers and extensive parallel evolution associated with attenuated progression. We identify genetic diversity and chromosomal complexity as determinants of patient outcome. Our insights reconcile the variable clinical behavior of ccRCC and suggest evolutionary potential as a biomarker for both intervention and surveillance.
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Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Biomarcadores Tumorais , Cromossomos , Evolução Clonal , Progressão da Doença , Evolução Molecular , Feminino , Heterogeneidade Genética , Variação Genética , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Mutação , Metástase Neoplásica , Fenótipo , Filogenia , Prognóstico , Estudos Prospectivos , Análise de Sequência de DNARESUMO
Clear-cell renal cell carcinoma (ccRCC) exhibits a broad range of metastatic phenotypes that have not been systematically studied to date. Here, we analyzed 575 primary and 335 metastatic biopsies across 100 patients with metastatic ccRCC, including two cases sampledat post-mortem. Metastatic competence was afforded by chromosome complexity, and we identify 9p loss as a highly selected event driving metastasis and ccRCC-related mortality (p = 0.0014). Distinct patterns of metastatic dissemination were observed, including rapid progression to multiple tissue sites seeded by primary tumors of monoclonal structure. By contrast, we observed attenuated progression in cases characterized by high primary tumor heterogeneity, with metastatic competence acquired gradually and initial progression to solitary metastasis. Finally, we observed early divergence of primitive ancestral clones and protracted latency of up to two decades as a feature of pancreatic metastases.
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Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Mutação , Metástase Neoplásica , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Biópsia , Mapeamento Cromossômico , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 9 , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Trombose , Resultado do TratamentoRESUMO
The earliest events during human tumour initiation, although poorly characterized, may hold clues to malignancy detection and prevention1. Here we model occult preneoplasia by biallelic inactivation of TP53, a common early event in gastric cancer, in human gastric organoids. Causal relationships between this initiating genetic lesion and resulting phenotypes were established using experimental evolution in multiple clonally derived cultures over 2 years. TP53 loss elicited progressive aneuploidy, including copy number alterations and structural variants prevalent in gastric cancers, with evident preferred orders. Longitudinal single-cell sequencing of TP53-deficient gastric organoids similarly indicates progression towards malignant transcriptional programmes. Moreover, high-throughput lineage tracing with expressed cellular barcodes demonstrates reproducible dynamics whereby initially rare subclones with shared transcriptional programmes repeatedly attain clonal dominance. This powerful platform for experimental evolution exposes stringent selection, clonal interference and a marked degree of phenotypic convergence in premalignant epithelial organoids. These data imply predictability in the earliest stages of tumorigenesis and show evolutionary constraints and barriers to malignant transformation, with implications for earlier detection and interception of aggressive, genome-instable tumours.
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Transformação Celular Neoplásica , Evolução Clonal , Lesões Pré-Cancerosas , Seleção Genética , Neoplasias Gástricas , Humanos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Evolução Clonal/genética , Instabilidade Genômica , Mutação , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Organoides/metabolismo , Organoides/patologia , Aneuploidia , Variações do Número de Cópias de DNA , Análise de Célula Única , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Progressão da Doença , Linhagem da CélulaRESUMO
Advances in spatial omics technologies now allow multiple types of data to be acquired from the same tissue slice. To realize the full potential of such data, we need spatially informed methods for data integration. Here, we introduce SpatialGlue, a graph neural network model with a dual-attention mechanism that deciphers spatial domains by intra-omics integration of spatial location and omics measurement followed by cross-omics integration. We demonstrated SpatialGlue on data acquired from different tissue types using different technologies, including spatial epigenome-transcriptome and transcriptome-proteome modalities. Compared to other methods, SpatialGlue captured more anatomical details and more accurately resolved spatial domains such as the cortex layers of the brain. Our method also identified cell types like spleen macrophage subsets located at three different zones that were not available in the original data annotations. SpatialGlue scales well with data size and can be used to integrate three modalities. Our spatial multi-omics analysis tool combines the information from complementary omics modalities to obtain a holistic view of cellular and tissue properties.
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Chromosomal instability in cancer consists of dynamic changes to the number and structure of chromosomes1,2. The resulting diversity in somatic copy number alterations (SCNAs) may provide the variation necessary for tumour evolution1,3,4. Here we use multi-sample phasing and SCNA analysis of 1,421 samples from 394 tumours across 22 tumour types to show that continuous chromosomal instability results in pervasive SCNA heterogeneity. Parallel evolutionary events, which cause disruption in the same genes (such as BCL9, MCL1, ARNT (also known as HIF1B), TERT and MYC) within separate subclones, were present in 37% of tumours. Most recurrent losses probably occurred before whole-genome doubling, that was found as a clonal event in 49% of tumours. However, loss of heterozygosity at the human leukocyte antigen (HLA) locus and loss of chromosome 8p to a single haploid copy recurred at substantial subclonal frequencies, even in tumours with whole-genome doubling, indicating ongoing karyotype remodelling. Focal amplifications that affected chromosomes 1q21 (which encompasses BCL9, MCL1 and ARNT), 5p15.33 (TERT), 11q13.3 (CCND1), 19q12 (CCNE1) and 8q24.1 (MYC) were frequently subclonal yet appeared to be clonal within single samples. Analysis of an independent series of 1,024 metastatic samples revealed that 13 focal SCNAs were enriched in metastatic samples, including gains in chromosome 8q24.1 (encompassing MYC) in clear cell renal cell carcinoma and chromosome 11q13.3 (encompassing CCND1) in HER2+ breast cancer. Chromosomal instability may enable the continuous selection of SCNAs, which are established as ordered events that often occur in parallel, throughout tumour evolution.
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Instabilidade Cromossômica/genética , Evolução Molecular , Cariótipo , Metástase Neoplásica/genética , Neoplasias/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 8/genética , Células Clonais/metabolismo , Células Clonais/patologia , Ciclina E/genética , Variações do Número de Cópias de DNA/genética , Feminino , Humanos , Perda de Heterozigosidade/genética , Masculino , Mutagênese , Metástase Neoplásica/patologia , Neoplasias/patologia , Proteínas Oncogênicas/genéticaRESUMO
Growing population and consumption pose unprecedented demands on food production. However, ammonia emissions mainly from food systems increase oceanic nitrogen deposition contributing to eutrophication. Here, we developed a long-term oceanic nitrogen deposition dataset (1970 to 2018) with updated ammonia emissions from food systems, evaluated the impact of ammonia emissions on oceanic nitrogen deposition patterns, and discussed the potential impact of nitrogen fertilizer overuse. Based on the chemical transport modeling approach, oceanic ammonia-related nitrogen deposition increased by 89% globally between 1970 and 2018, and now, it exceeds oxidized nitrogen deposition by over 20% in coastal regions including China Sea, India Coastal, and Northeastern Atlantic Shelves. Approximately 38% of agricultural nitrogen fertilizer was excessive, which corresponds to 15% of global oceanic ammonia-related nitrogen deposition. Policymakers and water quality managers need to pay increasingly more attention to ammonia associated with food production if the goal of reducing coastal nitrogen pollution is to be achieved for Sustainable Development Goals.
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Amônia , Nitrogênio , Nitrogênio/análise , Amônia/análise , Fertilizantes/análise , Agricultura , China , Qualidade da Água , SoloRESUMO
The roles of clock components in salt stress tolerance remain incompletely characterized in rice. Here, we show that, among OsPRR (Oryza sativa Pseudo-Response Regulator) family members, OsPRR73 specifically confers salt tolerance in rice. Notably, the grain size and yield of osprr73 null mutants were significantly decreased in the presence of salt stress, with accumulated higher level of reactive oxygen species and sodium ions. RNA sequencing and biochemical assays identified OsHKT2;1, encoding a plasma membrane-localized Na+ transporter, as a transcriptional target of OsPRR73 in mediating salt tolerance. Correspondingly, null mutants of OsHKT2;1 displayed an increased tolerance to salt stress. Immunoprecipitation-mass spectrometry (IP-MS) assays further identified HDAC10 as nuclear interactor of OsPRR73 and co-repressor of OsHKT2;1. Consistently, H3K9ac histone marks at OsHKT2;1 promoter regions were significantly reduced in osprr73 mutant. Together, our findings reveal that salt-induced OsPRR73 expression confers salt tolerance by recruiting HDAC10 to transcriptionally repress OsHKT2;1, thus reducing cellular Na+ accumulation. This exemplifies a new molecular link between clock components and salt stress tolerance in rice.
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Proteínas CLOCK/genética , Histona Desacetilases/metabolismo , Oryza/crescimento & desenvolvimento , Tolerância ao Sal , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Homeostase , Mutação com Perda de Função , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Sódio/metabolismoRESUMO
BACKGROUND: Systemic defects in intestinal iron absorption, circulation, and retention cause iron deficiency in 50% of patients with heart failure. Defective subcellular iron uptake mechanisms that are independent of systemic absorption are incompletely understood. The main intracellular route for iron uptake in cardiomyocytes is clathrin-mediated endocytosis. METHODS: We investigated subcellular iron uptake mechanisms in patient-derived and CRISPR/Cas-edited induced pluripotent stem cell-derived cardiomyocytes as well as patient-derived heart tissue. We used an integrated platform of DIA-MA (mass spectrometry data-independent acquisition)-based proteomics and signaling pathway interrogation. We employed a genetic induced pluripotent stem cell model of 2 inherited mutations (TnT [troponin T]-R141W and TPM1 [tropomyosin 1]-L185F) that lead to dilated cardiomyopathy (DCM), a frequent cause of heart failure, to study the underlying molecular dysfunctions of DCM mutations. RESULTS: We identified a druggable molecular pathomechanism of impaired subcellular iron deficiency that is independent of systemic iron metabolism. Clathrin-mediated endocytosis defects as well as impaired endosome distribution and cargo transfer were identified as a basis for subcellular iron deficiency in DCM-induced pluripotent stem cell-derived cardiomyocytes. The clathrin-mediated endocytosis defects were also confirmed in the hearts of patients with DCM with end-stage heart failure. Correction of the TPM1-L185F mutation in DCM patient-derived induced pluripotent stem cells, treatment with a peptide, Rho activator II, or iron supplementation rescued the molecular disease pathway and recovered contractility. Phenocopying the effects of the TPM1-L185F mutation into WT induced pluripotent stem cell-derived cardiomyocytes could be ameliorated by iron supplementation. CONCLUSIONS: Our findings suggest that impaired endocytosis and cargo transport resulting in subcellular iron deficiency could be a relevant pathomechanism for patients with DCM carrying inherited mutations. Insight into this molecular mechanism may contribute to the development of treatment strategies and risk management in heart failure.
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Cardiomiopatia Dilatada , Insuficiência Cardíaca , Células-Tronco Pluripotentes Induzidas , Deficiências de Ferro , Humanos , Miócitos Cardíacos/metabolismo , Mutação , Cardiomiopatia Dilatada/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Ferro/metabolismo , Clatrina/genética , Clatrina/metabolismo , Clatrina/farmacologiaRESUMO
Seeking noble-metal-free catalysts for efficient synthesis of aryl nitriles under mild conditions poses a significant challenge due to the use of hypertoxic cyanides or high-pressure/temperature NH3/O2 in conventional synthesis processes. Herein, we developed a novel framework 1 assembled by [Ni72] nanocages with excellent solvents/pH stability. To investigate the structure-activity relationship of catalytic performance, several isostructural MOFs with different molar ratios of Ni/Cu by doping Cu2+ into framework 1 (Ni0.59Cu0.41 (2), Ni0.81Cu0.19 (3), Ni0.88Cu0.12 (4), and Ni0.92Cu0.08 (5)) were prepared. Catalytic studies revealed that catalyst 3 exhibited remarkable performance in the synthesis of aryl nitriles, utilizing a formamide alternative to hypertoxic NaCN/KCN. Notably, catalyst 3 achieved an excellent TOF value of 9.8 h-1. Furthermore, catalyst 3 demonstrated its applicability in a gram-scale experiment and maintained its catalytic performance even after six recycling cycles, owing to its high stability resulting from significant electrostatic and orbital interactions between the Ni center and ligands as well as a large SOMO-LUMO energy gap supported by DFT calculations. Control experiments and DFT calculations further revealed that the excellent catalytic performance of catalyst 3 originated from the synergistic effect of Ni/Cu. Importantly, this work not only provides a highly feasible method to construct highly stable MOFs containing multinuclear nanocages with exceptional catalytic performance but also represents the first example of a heterogeneous catalyst for the synthesis of aryl nitriles using formamide as the cyanide source.
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The temporal component of episodic memory has been recognized as a sensitive behavioral marker in early stage of Alzheimer's disease (AD) patients. However, parallel studies in AD animals are currently lacking, and the underlying neural circuit mechanisms remain poorly understood. Using a novel AppNL-G-F knock-in (APP-KI) rat model, the developmental changes of temporal order memory (TOM) and the relationship with medial prefrontal cortex and perirhinal cortex (mPFC-PRH) circuit were determined through in vivo electrophysiology and microimaging technique. We observed a deficit in TOM performance during the object temporal order memory task (OTOMT) in APP-KI rats at 6 month old, which was not evident at 3 or 4 months of age. Alongside behavioral changes, we identified a gradually extensive and aggravated regional activation and functional alterations in the mPFC and PRH during the performance of OTOMT, which occurred prior to the onset of TOM deficits. Moreover, coherence analysis showed that the functional connectivity between the mPFC and PRH could predict the extent of future behavioral performance. Further analysis revealed that the aberrant mPFC-PRH interaction mainly attributed to the progressive deterioration of synaptic transmission, information flow and network coordination from mPFC to PRH, suggesting the mPFC dysfunction maybe the key area of origin underlying the early changes of TOM. These findings identify a pivotal role of the mPFC-PRH circuit in mediating the TOM deficits in the early stage of AD, which holds promising clinical translational value and offers potential early biological markers for predicting AD memory progression.
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Doença de Alzheimer , Córtex Perirrinal , Córtex Pré-Frontal , Animais , Córtex Pré-Frontal/fisiopatologia , Córtex Perirrinal/fisiologia , Doença de Alzheimer/fisiopatologia , Ratos , Masculino , Transtornos da Memória/fisiopatologia , Modelos Animais de Doenças , Ratos Transgênicos , Vias Neurais/fisiopatologia , Memória EpisódicaRESUMO
Emerging evidence suggests that tumor-specific neoantigens are ideal targets for cancer immunotherapy. However, how to predict tumor neoantigens based on translatome data remains obscure. Through the extraction of ribosome-nascent chain complexes (RNCs) from LLC cells, followed by RNC-mRNA extraction, RNC-mRNA sequencing, and comprehensive bioinformatic analysis, we successfully identified proteins undergoing translatome and exhibiting mutations in the cells. Subsequently, novel antigens identification was analyzed by the interaction between their high affinity and the Major Histocompatibility Complex (MHC). Neoantigens immunogenicity was analyzed by enzyme-linked immunospot assay (ELISpot). Finally, in vivo experiments in mice were conducted to evaluate the antitumor effects of translatome-derived neoantigen peptides on lung cancer. The results showed that ten neoantigen peptides were identified and synthesized by translatome data from LLC cells; 8 out of the 10 neoantigens had strong immunogenicity. The neoantigen peptide vaccine group exhibited significant tumor growth inhibition effect. In conclusion, neoantigen peptide vaccine derived from the translatome of lung cancer exhibited significant tumor growth inhibition effect.
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Antígenos de Neoplasias , Vacinas Anticâncer , Neoplasias Pulmonares , Vacinas de Subunidades Antigênicas , Animais , Antígenos de Neoplasias/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/terapia , Camundongos , Vacinas Anticâncer/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Humanos , Camundongos Endogâmicos C57BL , Feminino , Imunoterapia/métodos , Linhagem Celular Tumoral , Vacinas de Subunidades ProteicasRESUMO
In heterogeneous persulfate-catalyzed oxidation systems, the mechanism underlying the crystal plane effects of the catalyst on the selective conversion of reactive oxygen species (ROS) remains ambiguous. In this study, nano-Co3O4 catalysts with varying crystallinity and exposure levels of (111) crystal planes are prepared via a hydrothermal method. Compared to low crystalline catalysts, high crystallinity catalysts predominantly expose (111) planes containing higher concentrations of Co2+ and oxygen vacancies (Ov), resulting in an increase degradation efficiency of p-nitrobenzaldehyde (4-NBA) from 74.5% to 100%. Radical quenching experiments and EPR characterization reveal that the degradation of 4-NBA occurs through a radical pathway, and quantification of radicals demonstrates that increasing exposure levels of (111) planes effectively promote radical yield (CSO4â¢- increase from 18.2 to 172.8 µm and Câ¢OH increase from 1 to 58.9 µm). Furthermore, XPS and DFT calculations indicate that high crystallinity catalyst possesses more Ov active sites on (111) planes. The presence of Ov not only facilitates the adsorption of PMS molecules but also enhances electron transfer from Co2+ to PMS, leading to directed formation and efficient transformation of radicals. This study presents a novel strategy for promoting efficient radical formation in persulfate-activated systems.
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The portfolio of extraordinary fire retardancy, mechanical properties, dielectric/electric insulating performances, and thermal conductivity (λ) is essential for the practical applications of epoxy resin (EP) in high-end industries. To date, it remains a great challenge to achieve such a performanceportfolio in EP due to their different and even mutually exclusive governing mechanisms. Herein, a multifunctional additive (G@SiO2@FeHP) is fabricated by in situ immobilization of silica (SiO2) and iron phenylphosphinate (FeHP) onto the graphene (G) surface. Benefiting from the synergistic effect of G, SiO2 and FeHP, the addition of 1.0 wt% G@SiO2@FeHP enables EP to achieve a vertical burning (UL-94) V-0 rating and a limiting oxygen index (LOI) of 30.5%. Besides, both heat release and smoke generation of as-prepared EP nanocomposite are significantly suppressed due to the condensed-phase function of G@SiO2@FeHP. Adding 1.0 wt% G@SiO2@FeHP also brings about 44.5%, 61.1%, and 42.3% enhancements in the tensile strength, tensile modulus, and impact strength of EP nanocomposite. Moreover, the EP nanocomposite exhibits well-preserved dielectric and electric insulating properties and significantly enhanced λ. This work provides an integrated strategy for the development of multifunctional EP materials, thus facilitating their high-performance applications.
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Integration of multiple data sources presents a challenge for accurate prediction of molecular patho-phenotypic features in automated analysis of data from human model systems. Here, we applied a machine learning-based data integration to distinguish patho-phenotypic features at the subcellular level for dilated cardiomyopathy (DCM). We employed a human induced pluripotent stem cell-derived cardiomyocyte (iPSC-CM) model of a DCM mutation in the sarcomere protein troponin T (TnT), TnT-R141W, compared to isogenic healthy (WT) control iPSC-CMs. We established a multimodal data fusion (MDF)-based analysis to integrate source datasets for Ca2+ transients, force measurements, and contractility recordings. Data were acquired for three additional layer types, single cells, cell monolayers, and 3D spheroid iPSC-CM models. For data analysis, numerical conversion as well as fusion of data from Ca2+ transients, force measurements, and contractility recordings, a non-negative blind deconvolution (NNBD)-based method was applied. Using an XGBoost algorithm, we found a high prediction accuracy for fused single cell, monolayer, and 3D spheroid iPSC-CM models (≥92 ± 0.08â¯%), as well as for fused Ca2+ transient, beating force, and contractility models (>96 ± 0.04â¯%). Integrating MDF and XGBoost provides a highly effective analysis tool for prediction of patho-phenotypic features in complex human disease models such as DCM iPSC-CMs.
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Cardiomiopatia Dilatada , Células-Tronco Pluripotentes Induzidas , Aprendizado de Máquina , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/patologia , Cardiomiopatia Dilatada/patologia , Cardiomiopatia Dilatada/metabolismo , Humanos , Fenótipo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Troponina T/metabolismo , Cálcio/metabolismoRESUMO
Soil and rhizosphere bacteria act as a rich source of secondary metabolites, effectively fighting against a diverse array of pathogens. Certain Pseudomonas species harbor biosynthetic gene clusters for producing both pyoluteorin and 2,4-diacetylphloroglucinol (2,4-DAPG), which are polyketides that exhibit highly similar antimicrobial spectrum against bacteria and fungi or oomycete. A complex cross talk exists between pyoluteorin and 2,4-DAPG biosynthesis, and production of 2,4-DAPG was strongly repressed by pyoluteorin, yet the underlying mechanism is still elusive. In this study, we find that the TetR family transcription factor PhlH is involved in the cross talk between pyoluteorin and 2,4-DAPG biosynthesis. PhlH binds to a palindromic sequence within the promoter of phlG (PphlG), which encodes a C-C bond hydrolase responsible for degrading 2,4-DAPG. As a signaling molecule, pyoluteorin disrupts the PhlH-PphlG complex by binding to PhlH, leading to decreased levels of 2,4-DAPG. Proteomics data suggest that pyoluteorin regulates multiple physiological processes including fatty acid biosynthesis and transportation of taurine, siderophore, and amino acids. Our work not only reveals a novel mechanism of cross talk between pyoluteorin and 2,4-DAPG biosynthesis, but also highlights pyoluteorin's role as a messenger in the complex communication network of Pseudomonas.IMPORTANCEAntibiosis serves as a crucial defense mechanism for microbes against invasive bacteria and resource competition. These bacteria typically orchestrate the production of multiple antibiotics in a coordinated fashion, wherein the synthesis of one antibiotic inhibits the generation of another. This strategic coordination allows the bacterium to focus its resources on producing the most advantageous antibiotic under specific circumstances. However, the underlying mechanisms of distinct antibiotic production in bacterial cells remain largely elusive. In this study, we reveal that the TetR family transcription factor PhlH detects the secondary metabolite pyoluteorin and mediates the cross talk between pyoluteorin and 2,4-DAPG biosynthesis in the biocontrol strain Pseudomonas protegens Pf-5. These findings hold promise for future research, potentially informing the manipulation of these systems to enhance the effectiveness of biocontrol agents.
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Fenóis , Floroglucinol/análogos & derivados , Pseudomonas fluorescens , Pirróis , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação Bacteriana da Expressão Gênica , Pseudomonas/metabolismo , Antibacterianos/farmacologia , Pseudomonas fluorescens/genéticaRESUMO
Compared with traditional electrical logic gates, optical or terahertz (THz) computing logic gates have faster computing speeds and lower power consumption, and can better meet the huge data computing needs. However, there are limitations inherent in existing optical logic gates, such as single input/output channels and susceptibility to interference. Here, we proposed a new approach utilizing polarization-sensitive graphene-vanadium dioxide metasurface THz logic gates. Benefitting from two actively tunable materials, the proposed controlled-NOT logic gate(CNOT LG) enables versatile functionality through a dual-parameter control system. This system allows for the realization of multiple output states under diverse polarized illuminating conditions, aligning with the expected input-output logic relationship of the CNOT LG. Furthermore, to demonstrate the robustness of the designed THz CNOT LG metasurface, we designed an imaging array harnessing the dynamic control capabilities of tunable meta-atoms, facilitating clear near-field imaging. This research is promising for advancing CNOT LG applications in the THz spectrum. It has potential applications in telecommunications, sensing, and imaging.
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In order to enhance the performance of a continuous-wave photocathode electron gun at Peking University, and to achieve electron beams with higher current and brightness, a multifunctional drive laser system named PULSE (Peking University drive Laser System for high-brightness Electron source) has been developed. This innovative system is capable of delivering an average output power of 120 W infrared laser pulse at 81.25â MHz, as well as approximately 13.8 W of green power with reliable stability. The utilization of two stages of photonic crystal fibers plays a crucial role in achieving this output. Additionally, the incorporation of two acousto-optic modulators enables the selection of macro-pulses with varying repetition frequencies and duty cycles, which is essential for effective electron beam diagnosis. Furthermore, the system employs a series of birefringent crystals for temporal pulse shaping, allowing for stacking Gaussian pulses into multiple types of distribution. Overall, the optical schematic and operating performance of PULSE are detailed in this paper.
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We achieved an ultrahigh Q surface lattice resonance (SLR) using a conventional U-shaped split ring resonator (U-SRR) array. Numerical results confirmed by semi-analytical analysis show that with the transmission resonance amplitude up to 0.8, the Q-factor of the SLR can still surpass 104. The physical mechanisms of the ultrahigh Q-factor were also investigated. Besides the radiation suppression provided by conventional SLR, the unique geometry of the U-SRR can further offer dual radiation suppression mechanisms: reduction of the dipole moment and excitation of the in-plane quadrupole. We expect that the proposed ultrahigh Q SLR platform will be explored for more flexible and advanced nanoscale devices.
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In this work, we present a novel, to the best of our knowledge, lateral avalanche photodiode (APD) with low breakdown voltage and high bandwidth which has the potential to serve as a core device in future large-scale advanced optoelectronic hybrid chips. By taking advantage of a silicon-on-insulator (SOI) substrate combined with a separation absorption multiplier (SAM) structure, the demonstrated APDs exhibit a high gain of 148. Furthermore, the minimum breakdown voltage of the measured device is 6.1â V, which represents the lowest breakdown voltage for Si-APD, making it compatible with the existing CMOS technology for low voltage operation. Benefiting from an ultra-thin top silicon and lateral SAM structure, the problem of edge breakdown has been completely solved. Additionally, a set of device arrays with absorption and avalanche regions of different sizes is also manufactured and compared. Our findings indicate that the proposed APD has fascinating application prospects in the CMOS process-based LIDAR chips.