Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.150
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
EMBO J ; 42(24): e114051, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38059508

RESUMEN

CDK11 is an emerging druggable target for cancer therapy due to its prevalent roles in phosphorylating critical transcription and splicing factors and in facilitating cell cycle progression in cancer cells. Like other cyclin-dependent kinases, CDK11 requires its cognate cyclin, cyclin L1 or cyclin L2, for activation. However, little is known about how CDK11 activities might be modulated by other regulators. In this study, we show that CDK11 forms a tight complex with cyclins L1/L2 and SAP30BP, the latter of which is a poorly characterized factor. Acute degradation of SAP30BP mirrors that of CDK11 in causing widespread and strong defects in pre-mRNA splicing. Furthermore, we demonstrate that SAP30BP facilitates CDK11 kinase activities in vitro and in vivo, through ensuring the stabilities and the assembly of cyclins L1/L2 with CDK11. Together, these findings uncover SAP30BP as a critical CDK11 activator that regulates global pre-mRNA splicing.


Asunto(s)
Precursores del ARN , Empalme del ARN , Precursores del ARN/genética , Precursores del ARN/metabolismo , Fosforilación , División Celular , Ciclinas/genética , Ciclinas/metabolismo
2.
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
3.
Mol Cell ; 74(1): 118-131.e7, 2019 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-30819645

RESUMEN

Alternative polyadenylation (APA) produces mRNA isoforms with different 3' UTR lengths. Previous studies indicated that 3' end processing and mRNA export are intertwined in gene regulation. Here, we show that mRNA export factors generally facilitate usage of distal cleavage and polyadenylation sites (PASs), leading to long 3' UTR isoform expression. By focusing on the export receptor NXF1, which exhibits the most potent effect on APA in this study, we reveal several gene features that impact NXF1-dependent APA, including 3' UTR size, gene size, and AT content. Surprisingly, NXF1 downregulation results in RNA polymerase II (Pol II) accumulation at the 3' end of genes, correlating with its role in APA regulation. Moreover, NXF1 cooperates with CFI-68 to facilitate nuclear export of long 3' UTR isoform with UGUA motifs. Together, our work reveals important roles of NXF1 in coordinating transcriptional dynamics, 3' end processing, and nuclear export of long 3' UTR transcripts, implicating NXF1 as a nexus of gene regulation.


Asunto(s)
Núcleo Celular/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Poliadenilación , ARN Mensajero/biosíntesis , Proteínas de Unión al ARN/metabolismo , Transcripción Genética , Regiones no Traducidas 3' , Transporte Activo de Núcleo Celular , Sitios de Unión , Núcleo Celular/genética , Células HEK293 , Células HeLa , Humanos , Cinética , Proteínas de Transporte Nucleocitoplasmático/genética , Unión Proteica , ARN Polimerasa II/metabolismo , ARN Mensajero/genética , Proteínas de Unión al ARN/genética
4.
Genes Dev ; 33(9-10): 536-549, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30842217

RESUMEN

The exosome functions in the degradation of diverse RNA species, yet how it is negatively regulated remains largely unknown. Here, we show that NRDE2 forms a 1:1 complex with MTR4, a nuclear exosome cofactor critical for exosome recruitment, via a conserved MTR4-interacting domain (MID). Unexpectedly, NRDE2 mainly localizes in nuclear speckles, where it inhibits MTR4 recruitment and RNA degradation, and thereby ensures efficient mRNA nuclear export. Structural and biochemical data revealed that NRDE2 interacts with MTR4's key residues, locks MTR4 in a closed conformation, and inhibits MTR4 interaction with the exosome as well as proteins important for MTR4 recruitment, such as the cap-binding complex (CBC) and ZFC3H1. Functionally, MID deletion results in the loss of self-renewal of mouse embryonic stem cells. Together, our data pinpoint NRDE2 as a nuclear exosome negative regulator that ensures mRNA stability and nuclear export.


Asunto(s)
Exosomas/genética , Exosomas/metabolismo , Proteínas Nucleares/fisiología , ARN Helicasas/metabolismo , Animales , Núcleo Celular/metabolismo , Células Madre Embrionarias , Células HEK293 , Células HeLa , Humanos , Ratones , Proteínas Nucleares/genética , Unión Proteica , Dominios Proteicos , Transporte de Proteínas/genética , Estabilidad del ARN/genética
5.
J Biol Chem ; 300(5): 107269, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38588811

RESUMEN

Coenzyme Q10 (CoQ10) is an important cofactor and antioxidant for numerous cellular processes, and its deficiency has been linked to human disorders including mitochondrial disease, heart failure, Parkinson's disease, and hypertension. Unfortunately, treatment with exogenous CoQ10 is often ineffective, likely due to its extreme hydrophobicity and high molecular weight. Here, we show that less hydrophobic CoQ species with shorter isoprenoid tails can serve as viable substitutes for CoQ10 in human cells. We demonstrate that CoQ4 can perform multiple functions of CoQ10 in CoQ-deficient cells at markedly lower treatment concentrations, motivating further investigation of CoQ4 as a supplement for CoQ10 deficiencies. In addition, we describe the synthesis and evaluation of an initial set of compounds designed to target CoQ4 selectively to mitochondria using triphenylphosphonium. Our results indicate that select versions of these compounds can successfully be delivered to mitochondria in a cell model and be cleaved to produce CoQ4, laying the groundwork for further development.


Asunto(s)
Ataxia , Mitocondrias , Enfermedades Mitocondriales , Debilidad Muscular , Ubiquinona , Humanos , Mitocondrias/enzimología , Enfermedades Mitocondriales/enzimología , Enfermedades Mitocondriales/genética , Debilidad Muscular/enzimología , Debilidad Muscular/genética , Ubiquinona/análogos & derivados , Ubiquinona/deficiencia , Células Hep G2
6.
Plant J ; 118(2): 506-518, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38169508

RESUMEN

Thermosensitive genic female sterility (TGFS) is a promising property to be utilized for hybrid breeding. Here, we identified a rice TGFS line, tfs2, through an ethyl methyl sulfone (EMS) mutagenesis strategy. This line showed sterility under high temperature and became fertile under low temperature. Few seeds were produced when the tfs2 stigma was pollinated, indicating that tfs2 is female sterile. Gene cloning and genetic complementation showed that a point mutation from leucine to phenylalanine in HEI10 (HEI10tfs2), a crossover formation protein, caused the TGFS trait of tfs2. Under high temperature, abnormal univalents were formed, and the chromosomes were unequally segregated during meiosis, similar to the reported meiotic defects in oshei10. Under low temperature, the number of univalents was largely reduced, and the chromosomes segregated equally, suggesting that crossover formation was restored in tfs2. Yeast two-hybrid assays showed that HEI10 interacted with two putative protein degradation-related proteins, RPT4 and SRFP1. Through transient expression in tobacco leaves, HEI10 were found to spontaneously aggregate into dot-like foci in the nucleus under high temperature, but HEI10tfs2 failed to aggregate. In contrast, low temperature promoted HEI10tfs2 aggregation. This result suggests that protein aggregation at the crossover position contributes to the fertility restoration of tfs2 under low temperature. In addition, RPT4 and SRFP1 also aggregated into dot-like foci, and these aggregations depend on the presence of HEI10. These findings reveal a novel mechanism of fertility restoration and facilitate further understanding of HEI10 in meiotic crossover formation.


Asunto(s)
Infertilidad , Oryza , Intercambio Genético , Mutación Puntual , Oryza/genética , Fitomejoramiento
7.
Nat Chem Biol ; 19(3): 265-274, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36266351

RESUMEN

Pyruvate dehydrogenase complex (PDHC) and oxoglutarate dehydrogenase complex (OGDC), which belong to the mitochondrial α-ketoacid dehydrogenase family, play crucial roles in cellular metabolism. These multi-subunit enzyme complexes use lipoic arms covalently attached to their E2 subunits to transfer an acyl group to coenzyme A (CoA). Here, we report a novel mechanism capable of substantially inhibiting PDHC and OGDC: reactive nitrogen species (RNS) can covalently modify the thiols on their lipoic arms, generating a series of adducts that block catalytic activity. S-Nitroso-CoA, a product between RNS and the E2 subunit's natural substrate, CoA, can efficiently deliver these modifications onto the lipoic arm. We found RNS-mediated inhibition of PDHC and OGDC occurs during classical macrophage activation, driving significant rewiring of cellular metabolism over time. This work provides a new mechanistic link between RNS and mitochondrial metabolism with potential relevance for numerous physiological and pathological conditions in which RNS accumulate.


Asunto(s)
Brazo , Óxido Nítrico , 3-Metil-2-Oxobutanoato Deshidrogenasa (Lipoamida) , Complejo Piruvato Deshidrogenasa/metabolismo , Complejos Multienzimáticos
8.
J Lipid Res ; 65(3): 100525, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38417553

RESUMEN

The availability of genome-wide transcriptomic and proteomic datasets is ever-increasing and often not used beyond initial publication. Here, we applied module-based coexpression network analysis to a comprehensive catalog of 35 mouse genome-wide liver expression datasets (encompassing more than 3800 mice) with the goal of identifying and validating unknown genes involved in cholesterol metabolism. From these 35 datasets, we identified a conserved module of genes enriched with cholesterol biosynthetic genes. Using a systematic approach across the 35 datasets, we identified three genes (Rdh11, Echdc1, and Aldoc) with no known role in cholesterol metabolism. We then performed functional validation studies and show that each gene is capable of regulating cholesterol metabolism. For the glycolytic gene, Aldoc, we demonstrate that it contributes to de novo cholesterol biosynthesis and regulates cholesterol and triglyceride levels in mice. As Aldoc is located within a genome-wide significant genome-wide association studies locus for human plasma cholesterol levels, our studies establish Aldoc as a causal gene within this locus. Through our work, we develop a framework for leveraging mouse genome-wide liver datasets for identifying and validating genes involved in cholesterol metabolism.


Asunto(s)
Fructosa-Bifosfato Aldolasa , Estudio de Asociación del Genoma Completo , Humanos , Ratones , Animales , Fructosa-Bifosfato Aldolasa/genética , Fructosa-Bifosfato Aldolasa/metabolismo , Proteómica , Colesterol/metabolismo , Hígado/metabolismo
9.
J Biol Chem ; 299(11): 105333, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37827290

RESUMEN

Branched chain α-ketoacid dehydrogenase complex (BCKDC) is the rate-limiting enzyme in branched chain amino acid (BCAA) catabolism, a metabolic pathway with great importance for human health. BCKDC belongs to the mitochondrial α-ketoacid dehydrogenase complex family, which also includes pyruvate dehydrogenase complex and oxoglutarate dehydrogenase complex. Here, we revealed that BCKDC can be substantially inhibited by reactive nitrogen species (RNS) via a mechanism similar to what we recently discovered with pyruvate dehydrogenase complex and oxoglutarate dehydrogenase complex-RNS can cause inactivating covalent modifications of the lipoic arm on its E2 subunit. In addition, we showed that such reaction between RNS and the lipoic arm of the E2 subunit can further promote inhibition of the E3 subunits of α-ketoacid dehydrogenase complexes. We examined the impacts of this RNS-mediated BCKDC inhibition in muscle cells, an important site of BCAA metabolism, and demonstrated that the nitric oxide production induced by cytokine stimulation leads to a strong inhibition of BCKDC activity and BCAA oxidation in myotubes and myoblasts. More broadly, nitric oxide production reduced the level of functional lipoic arms across the multiple α-ketoacid dehydrogenases and led to intracellular accumulation of their substrates (α-ketoacids), decrease of their products (acyl-CoAs), and a lower cellular energy charge. In sum, this work revealed a new mechanism for BCKDC regulation, demonstrated that RNS can generally inhibit all α-ketoacid dehydrogenases, which has broad physiological implications across multiple cell types, and elucidated the mechanistic connection between RNS-driven inhibitory modifications on the E2 and E3 subunits of α-ketoacid dehydrogenases.


Asunto(s)
3-Metil-2-Oxobutanoato Deshidrogenasa (Lipoamida) , Células Musculares , Óxido Nítrico , Especies de Nitrógeno Reactivo , Humanos , 3-Metil-2-Oxobutanoato Deshidrogenasa (Lipoamida)/metabolismo , Aminoácidos de Cadena Ramificada/metabolismo , Complejo Cetoglutarato Deshidrogenasa , Células Musculares/metabolismo , Complejo Piruvato Deshidrogenasa , Especies de Nitrógeno Reactivo/metabolismo
10.
J Am Chem Soc ; 146(6): 4178-4186, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38301245

RESUMEN

DNA origami, comprising a long folded DNA scaffold and hundreds of linear DNA staple strands, has been developed to construct various sophisticated structures, smart devices, and drug delivery systems. However, the size and diversity of DNA origami are usually constrained by the length of DNA scaffolds themselves. Herein, we report a new paradigm of scaling up DNA origami assembly by introducing a novel branched staple concept. Owing to their covalent characteristics, the chemically conjugated branched DNA staples we describe here can be directly added to a typical DNA origami assembly system to obtain super-DNA origami with a predefined number of origami tiles in one pot. Compared with the traditional two-step coassembly system (yields <10%), a much greater yield (>80%) was achieved using this one-pot strategy. The diverse superhybrid DNA origami with the combination of different origami tiles can be also efficiently obtained by the hybrid branched staples. Furthermore, the branched staples can be successfully employed as the effective molecular glues to stabilize micrometer-scale, super-DNA origami arrays (e.g., 10 × 10 array of square origami) in high yields, paving the way to bridge the nanoscale precision of DNA origami with the micrometer-scale device engineering. This rationally developed assembly strategy for super-DNA origami based on chemically conjugated branched staples presents a new avenue for the development of multifunctional DNA origami-based materials.


Asunto(s)
Nanoestructuras , Nanoestructuras/química , Nanotecnología , ADN/química , Análisis de Secuencia por Matrices de Oligonucleótidos , Conformación de Ácido Nucleico
11.
Anal Chem ; 96(26): 10772-10779, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38902946

RESUMEN

A simple, sustainable, and sensitive monitoring approach of micro/nanoplastics (MNPs) in aqueous samples is crucial since it helps in assessing the extent of contamination and understanding the potential risks associated with their presence without causing additional stress to the environment. In this study, a novel strategy for qualitative and quantitative determination of MNPs in water by direct solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was proposed for the first time. Spherical poly(methyl methacrylate) (PMMA) and irregularly shaped polyvinyl dichloride (PVDC) were used to evaluate the feasibility and performance of the proposed method. The results demonstrated that both PMMA and PVDC MNPs were efficiently extracted by the homemade SPME coating of nitrogen-doped porous carbons (N-SPCs) and exhibited sufficient thermal decomposition in the GC-MS injection port. Excellent extraction performances of N-SPCs coating for MNPs are attributed to hydrophobic cross-linking, electrostatic forcing, hydrogen bonding, and pore trapping. Methyl methacrylate was identified as the marker for PMMA, while 1,3-dichlorobenzene and 1,3,5-trichlorobenzene were the indicators for PVDC. Under the optimal extraction and decomposition conditions, the proposed method exhibited ultrahigh sensitivity, with a limit of detection of 0.0041 µg/L for PMMA and 0.0054 µg/L for PVDC. Notably, a programmed temperature strategy for the GC-MS injector was developed to discriminate and eliminate the potential interferences of intrinsic indicator compounds. Owing to the integration of sampling, extraction, injection, and decomposition into one step by SPME, the proposed method demonstrates exceptional sensitivity, eliminating the necessity for complex sample pretreatment procedures and the use of organic solvents. Finally, the proposed method was successfully applied in the determination of PMMA and PVDC MNPs in real aqueous samples.

12.
Anal Chem ; 96(5): 2227-2235, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38272489

RESUMEN

Determinations of micro/nanoplastics (MNPs) in environmental samples are essential to assess the extent of their presence in the environment and their potential impact on ecosystems and human health. With the aim to provide a sensitive method with simplified pretreatment steps, cooling-assisted solid-phase microextraction (CA-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) is proposed as a new approach to quantify mass concentrations of MNPs in water and soil samples. The herein proposed CA-SPME method offers the unique advantage of integrating the thermal decomposition of MNPs and enrichment of signature compounds into one step. Poly(methyl methacrylate) (PMMA) was used as a model substance to verify the method performance in this work. Theoretical insights demonstrated that pyrolysis is the rate-determining step during the extraction process and that PMMA is effectively decomposed at 350 °C with an estimated incubation time of 13 min. Eight compounds were identified in the pyrolysis products by CA-SPME-GC-MS with the use of a DVB/CAR/PDMS coating, wherein methyl methacrylate was considered as the best indicator and dimethyl 2-methylenesuccinate was selected as the confirmation compound. Under the optimized conditions, the proposed method exhibited wide linearity (0.5-2000 µg for water and 5-1000 µg for soil) and high sensitivity, with limits of detection of 0.014 and 0.28 µg for water and soil, respectively. Finally, the proposed method was successfully applied for determinations of PMMA MNPs in real water and soil samples with satisfactory recoveries attained. The method only required the employment of a filter membrane for water analysis, while soil samples were analyzed directly without any pretreatment. The solvent-free approach, straightforward operation, and high sensitivity of the proposed method show great potential for the analysis of MNPs in different environmental samples.

13.
Radiology ; 311(1): e231852, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38625007

RESUMEN

Background Although favorable outcomes have been reported with radiofrequency ablation (RFA) for secondary hyperparathyroidism (SHPT), the long-term efficacy remains insufficiently investigated. Purpose To evaluate the long-term efficacy and safety of US-guided percutaneous RFA in patients with SHPT undergoing dialysis and to identify possible predictors associated with treatment failure. Materials and Methods This retrospective study included consecutive patients with SHPT with at least one enlarged parathyroid gland accessible for RFA who were undergoing dialysis at seven tertiary centers from May 2013 to July 2022. The primary end point was the proportion of patients with parathyroid hormone (PTH) levels less than or equal to 585 pg/mL at the end of follow-up. Secondary end points were the proportion of patients with normal calcium and phosphorus levels, the technical success rate, procedure-related complications, and improvement in self-rated hyperparathyroidism-related symptoms (0-3 ranking scale). The Wilcoxon signed rank test and generalized estimating equation model were used to evaluate treatment outcomes. Univariable and multivariable regression analyses identified variables associated with treatment failure (recurrent or persistent hyperparathyroidism). Results This study included 165 patients (median age, 51 years [IQR, 44-60 years]; 92 female) and 582 glands. RFA effectively reduced PTH, calcium, and phosphorus levels, with targeted ranges achieved in 78.2% (129 of 165), 72.7% (120 of 165), and 60.0% (99 of 165) of patients, respectively, at the end of follow-up (mean, 51 months). For the RFA sessions, the technical success rate was 100% (214 of 214). Median symptom scores (ostealgia, arthralgia, pruritus) decreased (all P < .001). Regarding complications, only hypocalcemia (45.8%, 98 of 214) was common. Treatment failure occurred in 36 patients (recurrent [n = 5] or persistent [n = 31] hyperparathyroidism). The only potential independent predictor of treatment failure was having less than four treated glands (odds ratio, 17.18; 95% CI: 4.34, 67.95; P < .001). Conclusion US-guided percutaneous RFA was effective and safe in the long term as a nonsurgical alternative for patients with SHPT undergoing dialysis; the only potential independent predictor of treatment failure was a lower number (<4) of treated glands. © RSNA, 2024 Supplemental material is available for this article.


Asunto(s)
Calcio , Hiperparatiroidismo Secundario , Humanos , Femenino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Hiperparatiroidismo Secundario/diagnóstico por imagen , Hiperparatiroidismo Secundario/cirugía , Fósforo
14.
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
15.
Chemistry ; 30(6): e202302857, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-37872690

RESUMEN

TiNb2 O7 with Wadsley-Roth phase delivers double theoretical specific capacity and similar working potential in comparison to spinel Li4 Ti5 O12 , the commercial high-rate anode material, and thus can enable much higher energy density of lithium-ion batteries. However, the inter-particle resistance within the high-mass-loading TiNb2 O7 electrode would impede the capacity release for practical application, especially under fast-charging conditions. Herein, 10-20 µm-size carbon-coated TiNb2 O7 secondary particle (SP-TiNb2 O7 ) consisting of initial micro-scale TiNb2 O7 particles (MP-TiNb2 O7 ) was fabricated. The high crystallinity of active material could enable fast-charge diffusion and electrochemical reaction rate within particles, and the small number of stacking layers of SP-TiNb2 O7 could reduce the large inter-particle resistance that regular particle electrode often possess and achieve high compaction density of electrodes with high mass loading. The investigation on materials structure and electrochemical reaction kinetics verified the advances of the as-fabricated SP-TiNb2 O7 in achieving superior electrochemical performance. The SP-TiNb2 O7 exhibited high reversible capacity of 292.7 mAh g-1 in the potential range of 1-3 V (Li+ /Li) at 0.1 C, delivering high-capacity release of 94.3 %, and high capacity retention of 86 % at 0.5 C for 250 cycles in half cell configuration. Particularly, the advances of such an anode were verified in practical 5 Ah-level laminated full pouch cell. The as-assembled LiFePO4 ||TiNb2 O7 full cell exhibited a high capacity of 5.08 Ah at high charging rate of 6 C (77.9 % of that at 0.2 C of 6.52 Ah), as well as an ultralow capacity decay rate of 0.0352 % for 250 cycles at 1 C, suggesting the great potential for practical fast-charging lithium-ion batteries.

16.
BMC Cancer ; 24(1): 464, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38616289

RESUMEN

PURPOSE: In this study, we retrospectively investigated the prognostic role of pre-treatment neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) in esophageal squamous cell carcinoma patients (ESCC) treated with concurrent chemo-radiotherapy (CCRT). METHODS: We retrospectively analyzed the records of 338 patients with pathologically diagnosed esophageal squamous cell carcinoma that underwent concurrent chemo-radiotherapy from January 2013 to December 2017. Univariate and multivariate analyses were used to identify prognostic factors for progression free survival (PFS) and overall survival (OS). RESULTS: The result showed that the thresholds for NLR and PLR were 2.47 and 136.0 by receiver operating characteristic curve. High NLR and PLR were both associated with tumor length (P < 0.05). High NLR and PLR were significantly associated with poor PFS and OS. Multivariate analyses identified NLR, PLR and TNM stage were independent risk factors for PFS and OS. CONCLUSIONS: We show that the pre-treatment NLR and PLR may serve as prognostic indicators for esophageal squamous cell carcinoma treated with concurrent chemo-radiotherapy.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Pronóstico , Carcinoma de Células Escamosas de Esófago/terapia , Neoplasias Esofágicas/terapia , Neutrófilos , Estudios Retrospectivos , Quimioradioterapia , Linfocitos
17.
J Fluoresc ; 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38252217

RESUMEN

A novel multi-functional fluorescence probe HMIC based on hydrazide Schiff base has been successfully synthesized and characterized. It can distinguish Al3+/Zn2+/Cd2+ in ethanol, in which fluorescence emission with different colors (blue for Al3+, orange for Zn2+, and green for Cd2+) were presented. The limits of detection of HMIC towards three ions were calculated from the titration curve as 7.70 × 10- 9 M, 4.64 × 10- 9 M, and 1.35 × 10- 8 M, respectively. The structures of HMIC and its complexes were investigated using UV-Vis spectra, Job's plot, infrared spectra, mass spectrometry, 1H-NMR and DFT calculations. Practical application studies have also demonstrated that HMIC can be applied to real samples with a low impact of potential interferents. Cytotoxicity and cellular imaging assays have shown that HMIC has good cellular permeability and potential antitumor effects. Interestingly, HMIC can image Al3+, Zn2+ and Cd2+ in the cells with different fluorescence signals.

18.
Anal Bioanal Chem ; 416(18): 4057-4070, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38842689

RESUMEN

A novel ferrofluid prepared from a hydrophobic deep eutectic solvent (DES) and Fe3O4@graphite composite materials was introduced as a green microextraction medium for the separation and enrichment of trace estrogens in real samples. It was found that the ferrofluid greatly improved the capacity and selectivity of target analytes, benefiting from the enrichment of both DES and Fe3O4@graphite composite materials. Using a combination of high-performance liquid chromatography-fluorescence detection (HPLC-FLD) and vortex-assisted liquid-liquid microextraction (VALLME), a new method was established for simultaneous rapid processing and accurate determination of three estrogens (estradiol [E2], estriol [E3], and ethinyl estradiol [EE2]) in environmental water and urine samples. Key parameters affecting the extraction efficiency were optimized using a single-factor approach and response surface methodology. Under optimal conditions, this method yielded a low limit of detection (1.01 ng L-1, 3.03 ng L-1, and 25.0 ng L-1 for EE2, E2, and E3, respectively), wide linear range (3-200,000 ng L-1), high enrichment factors (9.81-47.2), and satisfactory recovery (73.8-129.0%). Compared with traditional analytical techniques, this method avoids the use of volatile toxic organic extraction solvents and cumbersome phase separation operations.


Asunto(s)
Estrógenos , Interacciones Hidrofóbicas e Hidrofílicas , Límite de Detección , Microextracción en Fase Líquida , Contaminantes Químicos del Agua , Estrógenos/orina , Estrógenos/análisis , Contaminantes Químicos del Agua/orina , Contaminantes Químicos del Agua/análisis , Microextracción en Fase Líquida/métodos , Cromatografía Líquida de Alta Presión/métodos , Disolventes Eutécticos Profundos/química , Humanos
19.
Phys Chem Chem Phys ; 26(18): 13949-13954, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38668788

RESUMEN

Tavorite LiFeSO4F with high Li-ion conductivity has been considered a promising alternative to LiFePO4. However, its poor cycle stability and low electronic conductivity limit the practical application of Tavorite LiFeSO4F. In the present study, we employ a solvothermal method to produce magnesium-substitution LiMgxFe1-xSO4F (x = 0, 0.02, 0.04) cathode materials in which the Mg substitutes the Fe(2) sites. The first-principles calculations demonstrate that Mg-substitution could reduce the bandgap of LiFeSO4F and increase its electronic conductivity to 2.5 × 10-11 S cm-1. Meanwhile, CI-NEB and BV calculations reveal that the diffusion energy barrier of lithium along the (100) direction after Mg substitution is lower than the pristine sample, and the electrochemical inactive Mg2+ could improve the structure stability. The results show that the Mg-substituted LiFeSO4F exhibits enhanced cycle stability and rate performance compared with the pristine LiFeSO4F, suggesting that the use of electrochemically inactive ion substitution may be critical for the development of high-performance LiFeSO4F cathode materials for lithium-ion batteries.

20.
Int J Med Sci ; 21(2): 413-423, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38169572

RESUMEN

Introduction: Hepatocellular carcinoma (HCC) is the fourth most prevalent cancer in China. Transcatheter arterial chemoembolization (TACE) is a common interventional therapy for HCC. In this study, we aimed to explore specific metabolites that can accurately predict prognosis after TACE in patients with HCC. Methods: Patients with HCC and healthy volunteers (n = 20 each) were recruited to our study; plasma samples were collected from patients before and after TACE and from healthy volunteers. Plasma samples were subjected to untargeted ultra-high performance liquid chromatography-high resolution mass spectrometry metabolomics analysis, to identify metabolites significantly associated with the prognosis of patients with HCC after TACE. Results: Orthogonal filtered partial least squares discriminant analysis confirmed significant separation of the pre-TACE, post-TACE, and healthy groups, and 34 differential metabolites were identified between the pre-TACE and post-TACE groups. KEGG analysis revealed that phenylalanine, tyrosine, and tryptophan biosynthesis pathways and the phenylalanine metabolism pathway were potentially altered in HCC genesis and during TACE. Phenylalanine and tyrosine are involved in both pathways and were increased in the pre-TACE group relative to controls, with phenylalanine further increased in the post-TACE group. Receiver operating characteristic (ROC) curve analysis indicated that PC 36:4|PC 18:2_18:2 (area under the ROC curve (AUC) = 0.798) is a potential marker for assessment of prognosis in patients with HCC after TACE. Moreover, ROC curve analysis indicated that palmitoylcarnitine (AUC = 1) is a marker with potential value for HCC diagnosis. Conclusions: Limited studies had been conducted on the detection of metabolites in the plasma of HCC patients before and after TACE. PC 36:4|PC 18:2_18:2 is a potential marker for evaluation of the therapeutic effects of TACE. This finding may be beneficial for the treatment of patients with HCC after TACE.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Quimioembolización Terapéutica/métodos , Fenilalanina , Tirosina
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA