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1.
Cell ; 169(6): 1090-1104.e13, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28552346

RESUMEN

Genetic studies have elucidated critical roles of Piwi proteins in germline development in animals, but whether Piwi is an actual disease gene in human infertility remains unknown. We report germline mutations in human Piwi (Hiwi) in patients with azoospermia that prevent its ubiquitination and degradation. By modeling such mutations in Piwi (Miwi) knockin mice, we demonstrate that the genetic defects are directly responsible for male infertility. Mechanistically, we show that MIWI binds the histone ubiquitin ligase RNF8 in a Piwi-interacting RNA (piRNA)-independent manner, and MIWI stabilization sequesters RNF8 in the cytoplasm of late spermatids. The resulting aberrant sperm show histone retention, abnormal morphology, and severely compromised activity, which can be functionally rescued via blocking RNF8-MIWI interaction in spermatids with an RNF8-N peptide. Collectively, our findings identify Piwi as a factor in human infertility and reveal its role in regulating the histone-to-protamine exchange during spermiogenesis.


Asunto(s)
Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Azoospermia/genética , Mutación , Animales , Azoospermia/metabolismo , Cromatina/metabolismo , Análisis Mutacional de ADN , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Femenino , Técnicas de Sustitución del Gen , Histonas/metabolismo , Humanos , Intrones , Masculino , Ratones , Linaje , Protaminas/metabolismo , Proteolisis , Espermatogénesis , Ubiquitina-Proteína Ligasas , Ubiquitinación
2.
Plant Cell ; 36(5): 1637-1654, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38114096

RESUMEN

MicroRNAs (miRNAs) are a class of nonprotein-coding short transcripts that provide a layer of post-transcriptional regulation essential to many plant biological processes. MiR858, which targets the transcripts of MYB transcription factors, can affect a range of secondary metabolic processes. Although miR858 and its 187-nt precursor have been well studied in Arabidopsis (Arabidopsis thaliana), a systematic investigation of miR858 precursors and their functions across plant species is lacking due to a problem in identifying the transcripts that generate this subclass. By re-evaluating the transcript of miR858 and relaxing the length cut-off for identifying hairpins, we found in kiwifruit (Actinidia chinensis) that miR858 has long-loop hairpins (1,100 to 2,100 nt), whose intervening sequences between miRNA generating complementary sites were longer than all previously reported miRNA hairpins. Importantly, these precursors of miR858 containing long-loop hairpins (termed MIR858L) are widespread in seed plants including Arabidopsis, varying between 350 and 5,500 nt. Moreover, we showed that MIR858L has a greater impact on proanthocyanidin and flavonol levels in both Arabidopsis and kiwifruit. We suggest that an active MIR858L-MYB regulatory module appeared in the transition of early land plants to large upright flowering plants, making a key contribution to plant secondary metabolism.


Asunto(s)
Actinidia , Arabidopsis , Regulación de la Expresión Génica de las Plantas , MicroARNs , ARN de Planta , MicroARNs/genética , MicroARNs/metabolismo , Actinidia/genética , Actinidia/metabolismo , Arabidopsis/genética , ARN de Planta/genética , ARN de Planta/metabolismo , Semillas/genética , Semillas/metabolismo , Secuencia de Bases
3.
Plant Cell ; 36(5): 2000-2020, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38299379

RESUMEN

The flower-infecting fungus Ustilaginoidea virens causes rice false smut, which is a severe emerging disease threatening rice (Oryza sativa) production worldwide. False smut not only reduces yield, but more importantly produces toxins on grains, posing a great threat to food safety. U. virens invades spikelets via the gap between the 2 bracts (lemma and palea) enclosing the floret and specifically infects the stamen and pistil. Molecular mechanisms for the U. virens-rice interaction are largely unknown. Here, we demonstrate that rice flowers predominantly employ chitin-triggered immunity against U. virens in the lemma and palea, rather than in the stamen and pistil. We identify a crucial U. virens virulence factor, named UvGH18.1, which carries glycoside hydrolase activity. Mechanistically, UvGH18.1 functions by binding to and hydrolyzing immune elicitor chitin and interacting with the chitin receptor CHITIN ELICITOR BINDING PROTEIN (OsCEBiP) and co-receptor CHITIN ELICITOR RECEPTOR KINASE1 (OsCERK1) to impair their chitin-induced dimerization, suppressing host immunity exerted at the lemma and palea for gaining access to the stamen and pistil. Conversely, pretreatment on spikelets with chitin induces a defense response in the lemma and palea, promoting resistance against U. virens. Collectively, our data uncover a mechanism for a U. virens virulence factor and the critical location of the host-pathogen interaction in flowers and provide a potential strategy to control rice false smut disease.


Asunto(s)
Quitina , Flores , Hypocreales , Oryza , Enfermedades de las Plantas , Oryza/microbiología , Oryza/metabolismo , Oryza/genética , Enfermedades de las Plantas/microbiología , Quitina/metabolismo , Flores/microbiología , Hypocreales/patogenicidad , Hypocreales/genética , Hypocreales/metabolismo , Transducción de Señal , Interacciones Huésped-Patógeno , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Virulencia , Factores de Virulencia/metabolismo , Factores de Virulencia/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética
4.
Proc Natl Acad Sci U S A ; 121(20): e2322625121, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38709915

RESUMEN

Soft robots often draw inspiration from nature to navigate different environments. Although the inching motion and crawling motion of caterpillars have been widely studied in the design of soft robots, the steering motion with local bending control remains challenging. To address this challenge, we explore modular origami units which constitute building blocks for mimicking the segmented caterpillar body. Based on this concept, we report a modular soft Kresling origami crawling robot enabled by electrothermal actuation. A compact and lightweight Kresling structure is designed, fabricated, and characterized with integrated thermal bimorph actuators consisting of liquid crystal elastomer and polyimide layers. With the modular design and reprogrammable actuation, a multiunit caterpillar-inspired soft robot composed of both active units and passive units is developed for bidirectional locomotion and steering locomotion with precise curvature control. We demonstrate the modular design of the Kresling origami robot with an active robotic module picking up cargo and assembling with another robotic module to achieve a steering function. The concept of modular soft robots can provide insight into future soft robots that can grow, repair, and enhance functionality.

5.
Proc Natl Acad Sci U S A ; 121(8): e2319364121, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38359296

RESUMEN

Clonal hematopoiesis (CH) represents the clonal expansion of hematopoietic stem cells and their progeny driven by somatic mutations. Accurate risk assessment of CH is critical for disease prevention and clinical decision-making. The size of CH has been showed to associate with higher disease risk, yet, factors influencing the size of CH are unknown. In addition, the characteristics of CH in long-lived individuals are not well documented. Here, we report an in-depth analysis of CH in longevous (≥90 y old) and common (60~89 y old) elderly groups. Utilizing targeted deep sequencing, we found that the development of CH is closely related to age and the expression of aging biomarkers. The longevous elderly group exhibited a significantly higher incidence of CH and significantly higher frequency of TET2 and ASXL1 mutations, suggesting that certain CH could be beneficial to prolong life. Intriguingly, the size of CH neither correlates significantly to age, in the range of 60 to 110 y old, nor to the expression of aging biomarkers. Instead, we identified a strong correlation between large CH size and the number of mutations per individual. These findings provide a risk assessment biomarker for CH and also suggest that the evolution of the CH is influenced by factor(s) in addition to age.


Asunto(s)
Hematopoyesis Clonal , Hematopoyesis , Humanos , Anciano , Hematopoyesis Clonal/genética , Hematopoyesis/genética , Envejecimiento/genética , Mutación , Biomarcadores
6.
Proc Natl Acad Sci U S A ; 121(10): e2319366121, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38422020

RESUMEN

Acute myeloid leukemia (AML) is an aging-related and heterogeneous hematopoietic malignancy. In this study, a total of 1,474 newly diagnosed AML patients with RNA sequencing data were enrolled, and targeted or whole exome sequencing data were obtained in 94% cases. The correlation of aging-related factors including age and clonal hematopoiesis (CH), gender, and genomic/transcriptomic profiles (gene fusions, genetic mutations, and gene expression networks or pathways) was systematically analyzed. Overall, AML patients aged 60 y and older showed an apparently dismal prognosis. Alongside age, the frequency of gene fusions defined in the World Health Organization classification decreased, while the positive rate of gene mutations, especially CH-related ones, increased. Additionally, the number of genetic mutations was higher in gene fusion-negative (GF-) patients than those with GF. Based on the status of CH- and myelodysplastic syndromes (MDS)-related mutations, three mutant subgroups were identified among the GF- AML cohort, namely, CH-AML, CH-MDS-AML, and other GF- AML. Notably, CH-MDS-AML demonstrated a predominance of elderly and male cases, cytopenia, and significantly adverse clinical outcomes. Besides, gene expression networks including HOXA/B, platelet factors, and inflammatory responses were most striking features associated with aging and poor prognosis in AML. Our work has thus unraveled the intricate regulatory circuitry of interactions among different age, gender, and molecular groups of AML.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Anciano , Humanos , Masculino , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Envejecimiento/genética , Mutación , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Pronóstico
7.
Mol Cell ; 69(1): 62-74.e4, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29276085

RESUMEN

Alternative mRNA processing is a critical mechanism for proteome expansion and gene regulation in higher eukaryotes. The SR family proteins play important roles in splicing regulation. Intriguingly, mammalian genomes encode many poorly characterized SR-like proteins, including subunits of the mRNA 3'-processing factor CFIm, CFIm68 and CFIm59. Here we demonstrate that CFIm functions as an enhancer-dependent activator of mRNA 3' processing. CFIm regulates global alternative polyadenylation (APA) by specifically binding and activating enhancer-containing poly(A) sites (PASs). Importantly, the CFIm activator functions are mediated by the arginine-serine repeat (RS) domains of CFIm68/59, which bind specifically to an RS-like region in the CPSF subunit Fip1, and this interaction is inhibited by CFIm68/59 hyper-phosphorylation. The remarkable functional similarities between CFIm and SR proteins suggest that interactions between RS-like domains in regulatory and core factors may provide a common activation mechanism for mRNA 3' processing, splicing, and potentially other steps in RNA metabolism.


Asunto(s)
Empalme Alternativo/genética , Regulación de la Expresión Génica/genética , Poliadenilación , ARN Mensajero/metabolismo , Factores de Escisión y Poliadenilación de ARNm/metabolismo , Animales , Línea Celular , Elementos de Facilitación Genéticos/genética , Técnicas de Inactivación de Genes , Células HEK293 , Humanos , Fosforilación , Poli A/metabolismo , Dominios Proteicos/genética , Proteínas de Unión al ARN/metabolismo , Células Sf9 , Spodoptera
8.
Nature ; 568(7750): 108-111, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30918404

RESUMEN

Ethane is the second most abundant component of natural gas in addition to methane, and-similar to methane-is chemically unreactive. The biological consumption of ethane under anoxic conditions was suggested by geochemical profiles at marine hydrocarbon seeps1-3, and through ethane-dependent sulfate reduction in slurries4-7. Nevertheless, the microorganisms and reactions that catalyse this process have to date remained unknown8. Here we describe ethane-oxidizing archaea that were obtained by specific enrichment over ten years, and analyse these archaea using phylogeny-based fluorescence analyses, proteogenomics and metabolite studies. The co-culture, which oxidized ethane completely while reducing sulfate to sulfide, was dominated by an archaeon that we name 'Candidatus Argoarchaeum ethanivorans'; other members were sulfate-reducing Deltaproteobacteria. The genome of Ca. Argoarchaeum contains all of the genes that are necessary for a functional methyl-coenzyme M reductase, and all subunits were detected in protein extracts. Accordingly, ethyl-coenzyme M (ethyl-CoM) was identified as an intermediate by liquid chromatography-tandem mass spectrometry. This indicated that Ca. Argoarchaeum initiates ethane oxidation by ethyl-CoM formation, analogous to the recently described butane activation by 'Candidatus Syntrophoarchaeum'9. Proteogenomics further suggests that oxidation of intermediary acetyl-CoA to CO2 occurs through the oxidative Wood-Ljungdahl pathway. The identification of an archaeon that uses ethane (C2H6) fills a gap in our knowledge of microorganisms that specifically oxidize members of the homologous alkane series (CnH2n+2) without oxygen. Detection of phylogenetic and functional gene markers related to those of Ca. Argoarchaeum at deep-sea gas seeps10-12 suggests that archaea that are able to oxidize ethane through ethyl-CoM are widespread members of the local communities fostered by venting gaseous alkanes around these seeps.


Asunto(s)
Organismos Acuáticos/metabolismo , Archaea/metabolismo , Etano/metabolismo , Anaerobiosis , Archaea/clasificación , Archaea/enzimología , Archaea/genética , Deltaproteobacteria/metabolismo , Etano/química , Gases/química , Gases/metabolismo , Golfo de México , Metano/biosíntesis , Oxidación-Reducción , Oxidorreductasas/genética , Oxidorreductasas/aislamiento & purificación , Oxidorreductasas/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Sulfatos/metabolismo , Sulfuros/metabolismo
9.
Proc Natl Acad Sci U S A ; 119(38): e2201589119, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36095191

RESUMEN

In this work, we investigate the anelastic deformation behavior of periodic three-dimensional (3D) nanolattices with extremely thin shell thicknesses using nanoindentation. The results show that the nanolattice continues to deform with time under a constant load. In the case of 30-nm-thick aluminum oxide nanolattices, the anelastic deformation accounts for up to 18.1% of the elastic deformation for a constant load of 500 µN. The nanolattices also exhibit up to 15.7% recovery after unloading. Finite element analysis (FEA) coupled with diffusion of point defects is conducted, which is in qualitative agreement with the experimental results. The anelastic behavior can be attributed to the diffusion of point defects in the presence of a stress gradient and is reversible when the deformation is removed. The FEA model quantifies the evolution of the stress gradient and defect concentration and demonstrates the important role of a wavy tube profile in the diffusion of point defects. The reported anelastic deformation behavior can shed light on time-dependent response of nanolattice materials with implication for energy dissipation applications.

10.
Proc Natl Acad Sci U S A ; 119(40): e2201473119, 2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36161886

RESUMEN

Antimicrobial resistance (AMR) in soils represents a serious risk to human health through the food chain and human-nature contact. However, the active antibiotic-resistant bacteria (ARB) residing in soils that primarily drive AMR dissemination are poorly explored. Here, single-cell Raman-D2O coupled with targeted metagenomics is developed as a culture-independent approach to phenotypically and genotypically profiling active ARB against clinical antibiotics in a wide range of soils. This method quantifies the prevalence (contamination degree) and activity (spread potential) of soil ARB and reveals a clear elevation with increasing anthropogenic activities such as farming and the creation of pollution, thereby constituting a factor that is critical for the assessment of AMR risks. Further targeted sorting and metagenomic sequencing of the most active soil ARB uncover several uncultured genera and a pathogenic strain. Furthermore, the underlying resistance genes, virulence factor genes, and associated mobile genetic elements (including plasmids, insertion sequences, and prophages) are fully deciphered at the single-cell level. This study advances our understanding of the soil active AMR repertoire by linking the resistant phenome to the genome. It will aid in the risk assessment of environmental AMR and guide the combat under the One Health framework.


Asunto(s)
Antibacterianos , Bacterias , Farmacorresistencia Bacteriana , Metagenómica , Microbiología del Suelo , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/patogenicidad , Elementos Transponibles de ADN , Genes Bacterianos , Humanos , Análisis de la Célula Individual , Suelo , Factores de Virulencia/genética
11.
Proc Natl Acad Sci U S A ; 119(49): e2211429119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36442087

RESUMEN

The current classification of acute myeloid leukemia (AML) relies largely on genomic alterations. Robust identification of clinically and biologically relevant molecular subtypes from nongenomic high-throughput sequencing data remains challenging. We established the largest multicenter AML cohort (n = 655) in China, with all patients subjected to RNA sequencing (RNA-Seq) and 619 (94.5%) to targeted or whole-exome sequencing (TES/WES). Based on an enhanced consensus clustering, eight stable gene expression subgroups (G1-G8) with unique clinical and biological significance were identified, including two unreported (G5 and G8) and three redefined ones (G4, G6, and G7). Apart from four well-known low-risk subgroups including PML::RARA (G1), CBFB::MYH11 (G2), RUNX1::RUNX1T1 (G3), biallelic CEBPA mutations or -like (G4), four meta-subgroups with poor outcomes were recognized. The G5 (myelodysplasia-related/-like) subgroup enriched clinical, cytogenetic and genetic features mimicking secondary AML, and hotspot mutations of IKZF1 (p.N159S) (n = 7). In contrast, most NPM1 mutations and KMT2A and NUP98 fusions clustered into G6-G8, showing high expression of HOXA/B genes and diverse differentiation stages, from hematopoietic stem/progenitor cell down to monocyte, namely HOX-primitive (G7), HOX-mixed (G8), and HOX-committed (G6). Through constructing prediction models, the eight gene expression subgroups could be reproduced in the Cancer Genome Atlas (TCGA) and Beat AML cohorts. Each subgroup was associated with distinct prognosis and drug sensitivities, supporting the clinical applicability of this transcriptome-based classification of AML. These molecular subgroups illuminate the complex molecular network of AML, which may promote systematic studies of disease pathogenesis and foster the screening of targeted agents based on omics.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Humanos , Transcriptoma , Leucemia Mieloide Aguda/genética , Diferenciación Celular/genética , Células Madre Hematopoyéticas
12.
J Cell Mol Med ; 28(6): e18135, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38429900

RESUMEN

Lung adenocarcinoma (LUAD) is characterized by a high incidence rate and mortality. Recently, POC1 centriolar protein A (POC1A) has emerged as a potential biomarker for various cancers, contributing to cancer onset and development. However, the association between POC1A and LUAD remains unexplored. We extracted The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) data sets to analyse the differential expression of POC1A and its relationship with clinical stage. Additionally, we performed diagnostic receiver operator characteristic (ROC) curve analysis and Kaplan-Meier (KM) survival analysis to assess the diagnostic and prognostic value of POC1A in LUAD. Furthermore, we investigated the correlation between POC1A expression and immune infiltration, tumour mutation burden (TMB), immune checkpoint expression and drug sensitivity. Finally, we verified POC1A expression using real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). Cell experiments were conducted to validate the effect of POC1A expression on the proliferation, migration and invasion of lung cancer cells. POC1A exhibited overexpression in most tumour tissues, and its overexpression in LUAD was significantly correlated with late-stage presentation and poor prognosis. The high POC1A expression group showed lower levels of immune infiltration but higher levels of immune checkpoint expression and TMB. Moreover, the high POC1A expression group demonstrated sensitivity to multiple drugs. In vitro experiments confirmed that POC1A knockdown led to decreased proliferation, migration, and invasion of lung cancer cells. Our findings suggest that POC1A may contribute to tumour development by modulating the cell cycle and immune cell infiltration. It also represents a potential therapeutic target and marker for the diagnosis and prognosis of LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Adenocarcinoma del Pulmón/genética , Ciclo Celular , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , División Celular , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Neoplasias Pulmonares/genética , Regulación hacia Arriba/genética
13.
BMC Genomics ; 25(1): 346, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580907

RESUMEN

BACKGROUND: The yak (Bos grunniens) is a large ruminant species that lives in high-altitude regions and exhibits excellent adaptation to the plateau environments. To further understand the genetic characteristics and adaptive mechanisms of yak, we have developed a multi-omics database of yak including genome, transcriptome, proteome, and DNA methylation data. DESCRIPTION: The Yak Genome Database ( http://yakgenomics.com/ ) integrates the research results of genome, transcriptome, proteome, and DNA methylation, and provides an integrated platform for researchers to share and exchange omics data. The database contains 26,518 genes, 62 transcriptomes, 144,309 proteome spectra, and 22,478 methylation sites of yak. The genome module provides access to yak genome sequences, gene annotations and variant information. The transcriptome module offers transcriptome data from various tissues of yak and cattle strains at different developmental stages. The proteome module presents protein profiles from diverse yak organs. Additionally, the DNA methylation module shows the DNA methylation information at each base of the whole genome. Functions of data downloading and browsing, functional gene exploration, and experimental practice were available for the database. CONCLUSION: This comprehensive database provides a valuable resource for further investigations on development, molecular mechanisms underlying high-altitude adaptation, and molecular breeding of yak.


Asunto(s)
Multiómica , Proteoma , Animales , Bovinos/genética , Proteoma/genética , Genoma , Transcriptoma , Anotación de Secuencia Molecular
14.
Cancer Sci ; 115(5): 1611-1621, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38354746

RESUMEN

Chinese guidelines recommend POF (paclitaxel, oxaliplatin, and 5-FU/levoleucovorin) as first-line treatment for advanced gastric cancer (AGC). Apatinib can augment the antitumor effect of paclitaxel, oxaliplatin, or fluorouracil in preclinical studies of AGC. A phase I clinical trial was conducted to evaluate the anticancer activity and maximum tolerated dose (MTD) of apatinib plus POF in treatment-naïve patients with AGC and to establish a recommended phase II dose. Participants received escalating doses of daily oral apatinib (250, 375, 500, 625, 750, and 850 mg) plus POF every 2 weeks using a conventional "3 + 3" study design. Among 21 treated patients, one experienced a dose-limiting toxicity (grade 3 skin ulceration at 850 mg). No MTD was reached. Apatinib 750 mg plus POF was recommended for phase II study. The most common grade 3-4 adverse events (AEs) were neutropenia (33.3%), mucositis (14.3%), and hand-foot syndrome (14.3%). Median progression-free and overall survival were 10.4 months (95% CI: 6.3, 14.6) and 18.4 months (95% CI: 9.8, 28.2), respectively. Apatinib up to 850 mg coadministered with POF was well tolerated with manageable AEs. The safety and anticancer activity of this regimen warrants its further investigation as first-line treatment for AGC in a larger study.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Fluorouracilo , Leucovorina , Dosis Máxima Tolerada , Oxaliplatino , Paclitaxel , Piridinas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Persona de Mediana Edad , Masculino , Femenino , Piridinas/administración & dosificación , Piridinas/efectos adversos , Piridinas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Anciano , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Paclitaxel/uso terapéutico , Adulto , Oxaliplatino/administración & dosificación , Oxaliplatino/uso terapéutico , Oxaliplatino/efectos adversos , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Fluorouracilo/uso terapéutico , Leucovorina/administración & dosificación , Leucovorina/uso terapéutico , Leucovorina/efectos adversos
15.
Small ; : e2404792, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38923291

RESUMEN

Electrochemically converting nitrate (NO3 -) into ammonia (NH3) has emerged as an alternative strategy for NH3 production and effluent treatment. Nevertheless, the electroreduction of dilute NO3 - is still challenging due to the competitive adsorption between various aqueous species and NO3 -, and unfavorable water dissociation providing *H. Herein, a new tandem strategy is proposed to boost the electrochemical nitrate reduction reaction (NO3RR) performance of Cu nanoparticles supported on single Fe atoms dispersed N-doped carbon (Cu@Fe1-NC) at dilute NO3 - concentrations (≤100 ppm NO3 --N). The optimized Cu@Fe1-NC presents a FENH3 of 97.7% at -0.4 V versus RHE, and a significant NH3 yield of 1953.9 mmol h-1 gCu -1 at 100 ppm NO3 --N, a record-high activity for dilute NO3RR. The metal/carbon heterojunctions in Cu@Fe1-NC enable a spontaneous electron transfer from Cu to carbon substrate, resulting in electron-deficient Cu. As a result, the electron-deficient Cu facilitates the adsorption of NO3 - compared with the pristine Cu. The adjacent atomic Fe sites efficiently promote water dissociation, providing abundant *H for the hydrogenation of *NOx e at Cu sites. The synergistic effects between Cu and single Fe atom sites simultaneously decrease the energy barrier for NO3 - adsorption and hydrogenation, thereby enhancing the overall activity of NO3 - reduction.

16.
Small ; : e2307709, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438885

RESUMEN

The activation of the host adaptive immune system is crucial for eliminating viruses. However, influenza infection often suppresses the innate immune response that precedes adaptive immunity, and the adaptive immune responses are typically delayed. Dendritic cells, serving as professional antigen-presenting cells, have a vital role in initiating the adaptive immune response. In this study, an immuno-stimulating antiviral system (ISAS) is introduced, which is composed of the immuno-stimulating adjuvant lipopeptide Pam3CSK4 that acts as a scaffold onto which it is covalently bound 3 to 4 influenza-inhibiting peptides. The multivalent display of peptides on the scaffold leads to a potent inhibition against H1N1 (EC50  = 20 nM). Importantly, the resulting lipopeptide, Pam3FDA, shows an irreversible inhibition mechanism. The chemical modification of peptides on the scaffold maintains Pam3CSK4's ability to stimulate dendritic cell maturation, thereby rendering Pam3FDA a unique antiviral. This is attributed to its immune activation capability, which also acts in synergy to expedite viral elimination.

17.
Plant Biotechnol J ; 22(1): 116-130, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37752622

RESUMEN

Arabidopsis RESISTANCE TO POWDERY MILDEW 8.1 (RPW8.1) is an important tool for engineering broad-spectrum disease resistance against multiple pathogens. Ectopic expression of RPW8.1 leads to enhanced disease resistance with cell death at leaves and compromised plant growth, implying a regulatory mechanism balancing RPW8.1-mediated resistance and growth. Here, we show that RPW8.1 constitutively enhances the expression of transcription factor WRKY51 and activates salicylic acid and ethylene signalling pathways; WRKY51 in turn suppresses RPW8.1 expression, forming a feedback regulation loop. RPW8.1 and WRKY51 are both induced by pathogen infection and pathogen-/microbe-associated molecular patterns. In ectopic expression of RPW8.1 background (R1Y4), overexpression of WRKY51 not only rescues the growth suppression and cell death caused by RPW8.1, but also suppresses RPW8.1-mediated broad-spectrum disease resistance and pattern-triggered immunity. Mechanistically, WRKY51 directly binds to and represses RPW8.1 promoter, thus limiting the expression amplitude of RPW8.1. Moreover, WRKY6, WRKY28 and WRKY41 play a role redundant to WRKY51 in the suppression of RPW8.1 expression and are constitutively upregulated in R1Y4 plants with WRKY51 being knocked out (wrky51 R1Y4) plants. Notably, WRKY51 has no significant effects on disease resistance or plant growth in wild type without RPW8.1, indicating a specific role in RPW8.1-mediated disease resistance. Altogether, our results reveal a regulatory circuit controlling the accumulation of RPW8.1 to an appropriate level to precisely balance growth and disease resistance during pathogen invasion.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Resistencia a la Enfermedad/genética , Retroalimentación , Arabidopsis/metabolismo , Muerte Celular , Enfermedades de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/genética
18.
Glob Chang Biol ; 30(3): e17250, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38500362

RESUMEN

Nitrogen (N) deposition affects ecosystem functions crucial to human health and well-being. However, the consequences of this scenario for soil ecosystem multifunctionality (SMF) in forests are poorly understood. Here, we conducted a long-term field experiment in a temperate forest in China, where N deposition was simulated by adding N above and under the canopies. We discover that canopy N addition promotes SMF expression, whereas understory N addition suppresses it. SMF was regulated by fungal diversity in canopy N addition treatments, which is largely due to the strong resistance to soil acidification and efficient resource utilization characteristics of fungi. While in understory N addition treatments, SMF is regulated by bacterial diversity, which is mainly because of the strong resilience to disturbances and fast turnover of bacteria. Furthermore, rare microbial taxa may play a more important role in the maintenance of the SMF. This study provides the first evidence that N deposition enhanced SMF in temperate forests and enriches the knowledge on enhanced N deposition affecting forest ecosystems. Given the divergent results from two N addition approaches, an innovative perspective of canopy N addition on soil microbial diversity-multifunctionality relationships is crucial to policy-making for the conservation of soil microbial diversity and sustainable ecosystem management under enhanced N deposition. In future research, the consideration of canopy N processes is essential for more realistic assessments of the effects of atmospheric N deposition in forests.


Asunto(s)
Ecosistema , Nitrógeno , Humanos , Nitrógeno/análisis , Suelo , Microbiología del Suelo , Bosques , Bacterias/metabolismo
19.
Chemistry ; 30(34): e202401154, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38627216

RESUMEN

A method was developed to link two or three o-carborane moieties to form a series of carboranyl dithioester bridging ligands via in situ substitution of haloalkanes by tetraphenylphosphonium carboranyldithiocarboxylates. Based on these ligands, direct B-H activation without the assistance of Ag(I) and alkali was successfully achieved with half-sandwich Ir(III) substrate [Cp*IrCl2]2 to yield corresponding bimetallic or trimetallic complexes. Single crystal structure analyses of the B-H activated complexes and corresponding SnCl2-inserted derivatives confirm the selective B(3)-H activation in these complexes.

20.
J Endovasc Ther ; : 15266028241259391, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38887028

RESUMEN

OBJECTIVE: The study was to figure out the feasibility, efficacy, and safety of a single-branched stent graft, namely Castor, in combination with fenestration or chimney in the context of aortic arch lesions presenting with aberrant subclavian artery (ASA) and/or Kommerell's diverticulum (KD). METHODS: All consecutive patients with aortic arch lesions and ASA and/or KD receiving Castor from June 2018 to June 2023 were investigated. RESULTS: Incorporating 18 patients, the study encompassed 11 cases with KD, 3 cases with dysphagia; 2 cases of right-sided aortic arch with left-sided aberrant left subclavian artery (ALSA), and 16 cases of left-sided aortic arch with right-sided aberrant right subclavian artery (ARSA). The mean operation time was 132±23 minutes. The mean measured proximal aortic diameter was 30.9±1.6 mm, and proximal diameter of Castor stent was 34 (32, 34.5) mm, with oversize of 9.1±1.6%; the mean measured branch diameter was 8.8±0.97 mm, and branch diameter of Castor stent was 10 (8, 10) mm, with oversize of 0.86±0.57 mm. Technical success rate was 100%, and no in-hospital mortality, no stroke, and no endoleak were identified. One (5.6%) case with spinal cord ischemia and one (5.6%) case with poor healing of operative site were identified. During the follow-up period, no aortic-related death or secondary intervention was recorded. The maximal aortic diameter was significantly reduced at the sixth postoperative month (padj=0.031); KD diameter was significantly reduced at the third (padj=0.001) and sixth (padj<0.001) postoperative month. CONCLUSION: Totally endovascular repair of aortic arch lesions with ASA and KD via Castor stent in combination with fenestration or chimney is feasible, effective, and safe, which can achieve an encouraging medium-term outcome and provide excellent remodeling at the lesions. CLINICAL IMPACT: Single branched stent in combination with fenestration or chimney achieved a sufficient proximal landing zone and provided an encouraging medium-term outcome in this retrospective review of 18 patients receiving endovascular treatment of pathological aortic arch with aberrant subclavian artery and/or Kommerell's diverticulum. The authors suggest this time-saving and efficient technique to establish systematic experience for the treatment in this kind of patients.

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