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1.
Crit Rev Eukaryot Gene Expr ; 34(1): 55-68, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37824392

RESUMEN

Bladder cancer (BC) is the second most common genitourinary malignancy. Long noncoding RNA (lncRNA) is implicated in BC progression. This study delved into the underlying mechanism of lncRNA MEG3 in BC. Bioinformatics analysis predicted the expression of lncRNA MEG3, its association with the survival of BC patients, its subcellular localization, and its binding sites with miR-21-5p. Differentially expressed genes (DEGs) in the GSE13507 chip were analyzed using GEOexplorer, downstream targets of miR-21-5p were predicted from databases, and the overlapping genes were analyzed by the website Venny2.1 (https://bioinfogp.cnb.csic.es/tools/venny/index.html); their impacts on patient survival were analyzed by the Starbase database. The expression of SPRY2 and TGFBI associated with patient survival was analyzed in TCGA. RT-qPCR and western blot were performed to detect levels of MEG3, miR-21-5p, and SPRY2 in BC/SV-HUC-1 cells. Malignant biological behaviors of BC cells were detected using CCK8, flow cytometry, and Transwell assays. RNA pull-down and dual-luciferase assays were employed to verify the binding relationship of miR-21-5p with MEG3 and SPRY2. MEG3 was found to be lowly expressed in BC cells and mainly distributed in the cytoplasm. Over-expression of MEG3 was found to inhibit BC cell activity, promote apoptosis, and reduce invasion and migration. miR-21-5p was found to be highly expressed in BC cells, and its down-regulation was found to inhibit the malignant behavior of BC cells. Over-expression of miR-21-5p was found to reverse the effect of pcDNA3.1-MEG3 on BC cells. MEG3 was found to competitively bind to miR-21-5p as a ceRNA to promote SPRY2 levels. LncRNA MEG3 promotes SPRY2 expression by competitively binding to miR-21-5p, thereby inhibiting proliferation and promoting apoptosis of BC cells.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Neoplasias de la Vejiga Urinaria , Humanos , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de la Membrana/genética , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Neoplasias de la Vejiga Urinaria/genética
2.
Cell Mol Life Sci ; 80(8): 230, 2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37498355

RESUMEN

The aberrant activation of the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is known to contribute to the pathogenesis of various human inflammation-related diseases. However, to date, no small-molecule NLRP3 inhibitor has been used in clinical settings. In this study, we have identified SB-222200 as a novel direct NLRP3 inhibitor through the use of drug affinity responsive target stability assay, cellular thermal shift assay, and surface plasmon resonance analysis. SB-222200 effectively inhibits the activation of the NLRP3 inflammasome in macrophages, while having no impact on the activation of NLRC4 or AIM2 inflammasome. Furthermore, SB-222200 directly binds to the NLRP3 protein, inhibiting NLRP3 inflammasome assembly by blocking the NEK7 - NLRP3 interaction and NLRP3 oligomerization. Importantly, treatment with SB-222200 demonstrates alleviation of NLRP3-dependent inflammatory diseases in mouse models, such as monosodium urate crystal-induced peritonitis and dextran sulfate sodium-induced acute intestinal inflammation. Therefore, SB-222200 holds promise as a lead compound for the development of NLRP3 inhibitors to combat NLRP3-driven disease and serves as a versatile tool for pharmacologically investigating NLRP3 biology.


Asunto(s)
Proteína con Dominio Pirina 3 de la Familia NLR , Peritonitis , Ratones , Animales , Humanos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Inflamasomas/metabolismo , Peritonitis/inducido químicamente , Peritonitis/tratamiento farmacológico , Peritonitis/metabolismo , Macrófagos/metabolismo , Inflamación/metabolismo , Ratones Endogámicos C57BL , Interleucina-1beta/metabolismo
3.
Nano Lett ; 23(22): 10282-10289, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37906179

RESUMEN

Quasiparticles consisting of correlated electron(s) and hole(s), such as excitons and trions, play important roles in the optical phenomena of van der Waals semiconductors and serve as unique platforms for studies of many-body physics. Herein, we report a gate-tunable exciton-to-trion transition in pressurized monolayer MoSe2, in which the electronic band structures are modulated continuously within a diamond anvil cell. The emission energies of both the exciton and trion undergo large blueshifts over 90 meV with increasing pressure. Surprisingly, the trion binding energy remains constant at 30 meV, regardless of the applied pressure. Combining ab initio density functional theory calculations and quantum Monte Carlo simulations, we find that the remarkable robustness of the trion binding energy originates from the spatially diffused nature of the trion wave function and the weak correlation between its constituent electron-hole pairs. Our findings shed light on the optical properties of correlated excitonic quasiparticles in low-dimensional materials.

4.
J Integr Plant Biol ; 66(7): 1295-1312, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38695649

RESUMEN

Cultivating high-yield wheat under limited water resources is crucial for sustainable agriculture in semiarid regions. Amid water scarcity, plants activate drought response signaling, yet the delicate balance between drought tolerance and development remains unclear. Through genome-wide association studies and transcriptome profiling, we identified a wheat atypical basic helix-loop-helix (bHLH) transcription factor (TF), TabHLH27-A1, as a promising quantitative trait locus candidate for both relative root dry weight and spikelet number per spike in wheat. TabHLH27-A1/B1/D1 knock-out reduced wheat drought tolerance, yield, and water use efficiency (WUE). TabHLH27-A1 exhibited rapid induction with polyethylene glycol (PEG) treatment, gradually declining over days. It activated stress response genes such as TaCBL8-B1 and TaCPI2-A1 while inhibiting root growth genes like TaSH15-B1 and TaWRKY70-B1 under short-term PEG stimulus. The distinct transcriptional regulation of TabHLH27-A1 involved diverse interacting factors such as TaABI3-D1 and TabZIP62-D1. Natural variations of TabHLH27-A1 influence its transcriptional responses to drought stress, with TabHLH27-A1Hap-II associated with stronger drought tolerance, larger root system, more spikelets, and higher WUE in wheat. Significantly, the excellent TabHLH27-A1Hap-II was selected during the breeding process in China, and introgression of TabHLH27-A1Hap-II allele improved drought tolerance and grain yield, especially under water-limited conditions. Our study highlights TabHLH27-A1's role in balancing root growth and drought tolerance, providing a genetic manipulation locus for enhancing WUE in wheat.


Asunto(s)
Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Raíces de Plantas , Triticum , Agua , Triticum/genética , Triticum/crecimiento & desarrollo , Triticum/fisiología , Triticum/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Agua/metabolismo , Sitios de Carácter Cuantitativo/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Estrés Fisiológico/genética , Estudio de Asociación del Genoma Completo , Resistencia a la Sequía
5.
Small ; 19(49): e2304303, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37566779

RESUMEN

Single-atom Fe catalysts are considered as the promising catalysts for oxygen reduction reaction (ORR). However, the high electronegativity of the symmetrical coordination N atoms around Fe site generally results in too strong adsorption of *OOH intermediates on the active site, severely limiting the catalytic performance. Herein, a "heteroatom pair synergetic modulation" strategy is proposed to tailor the coordination environment and spin state of Fe sites, enabling breaking the shackles of unsuitable adsorption of intermediate products on the active centers toward a more efficient ORR pathway. The unsymmetrically Co and B heteroatomic coordinated Fe single sites supported on an N-doped carbon (Fe─B─Co/NC) catalyst perform excellent ORR activity with high half-wave potential (E1/2 ) of 0.891 V and a large kinetic current density (Jk ) of 60.6 mA cm-2 , which is several times better than those of commercial Pt/C catalysts. By virtue of in situ electrochemical impedance and synchrotron infrared spectroscopy, it is observed that the optimized Fe sites can effectively accelerate the evolution of O2 into the *O intermediate, overcoming the sluggish O─O bond cleavage of the *OOH intermediate, which is responsible for fast four-electron reaction kinetics.

6.
Plant Cell Environ ; 46(11): 3420-3432, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37469026

RESUMEN

Drought and high salinity are major environmental factors that reduce plant growth and development, leading to loss of plant productivity in agriculture. Under these stress conditions, photosynthesis is greatly suppressed despite the high cellular energy cost of stress response processes. Currently, the process that allows plants to secure the energy required for osmotic stress responses remains elusive. Here, we provide evidence that cytochrome b5 reductase 1 (CBR1), a cytochrome b5 reductase, plays an important role in ATP production in response to NaCl and dehydration stresses. Overexpression and loss of function of CBR1 led to enhanced resistance and sensitivity, respectively, to osmotic stress. Upon exposure to osmotic stress, CBR1 was localised to the endoplasmic reticulum (ER) instead of to mitochondria, where it was localised under normal conditions. Transgenic plants overexpressing ER-targeted CBR1 showed enhanced resistance to osmotic stress. Moreover, CBR1-ER and CBR1-OX plants, had higher levels of ATP and unsaturated fatty acids under osmotic stress. However, these effects were abrogated by thioridazine and 2-deoxy glucose, inhibitors of ß-oxidation and glycolysis, respectively. Based on these results, we propose that ER-localised CBR1 triggers ATP production via the production and ß-oxidation of polyunsaturated fatty acids under osmotic stress.


Asunto(s)
Citocromos b5 , Ácidos Grasos Insaturados , Presión Osmótica/fisiología , Citocromos b5/farmacología , Oxidorreductasas , Retículo Endoplásmico , Mitocondrias , Adenosina Trifosfato , Estrés Fisiológico , Regulación de la Expresión Génica de las Plantas
7.
Crit Rev Food Sci Nutr ; 63(30): 10621-10635, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35593666

RESUMEN

Lycium genus (Goji berry) is recognized as a good source of homology of medicine and food, with various nutrients and phytochemicals. Lately, numerous studies have focused on the chemical constituents and biological functions of the L. barbarum L., covering phytochemical and pharmacological aspects. We aim to provide exclusive data on the nutrients of L. barbarum L. fruits and phytochemicals, including their structural characterization, the evolution of extraction, and purification processes of different phytochemicals of L. barbarum L. fruit while placing greater emphasis on their wide-ranging health effects. This review also profitably offers innovative approaches for the food industry and industrial applications of L. barbarum L. and addresses some current situations and problems in the development of L. barbarum L. in deep processing products, which can provide clues for the sustainable development of L. barbarum L. industry.


Asunto(s)
Lycium , Lycium/química , Alimentos Funcionales , Industria de Alimentos , Fitoquímicos/farmacología , Fitoquímicos/análisis , Frutas/química
8.
Phys Chem Chem Phys ; 25(5): 3848-3858, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36645197

RESUMEN

Utilization of a solar-driven semiconductor as a photocatalyst to degrade antibiotic pollutants is a feasible and environmentally friendly technology. In this paper, 3D chrysanthemum-like g-C3N4/TiO2 as a visible-light-driven hybrid photocatalyst with a Z-scheme heterostructure was firstly synthesized by the in situ hydrothermal synthesis method. Experiments proved that this 3D chrysanthemum-like g-C3N4/TiO2 had better degradation performance toward tetracycline than TiO2 and g-C3N4. In particular, when optimized g-C3N4/TiO2-2 was applied for tetracycline removal (200 ml, 10 mg L-1), the corresponding degradation efficiency could reach nearly 100% within 60 min. The improved photocatalytic activity was the result of better utilization of the heterostructure-induced visible light, more efficient charge transfer in the Z-scheme heterojunction as well as stronger redox capability. The Z-scheme degradation mechanism was supported by the trapping experiments of active species and ESR radical detection, and the whole photocatalytic process was controlled by the combined action of ˙O2-, h+ and ˙OH radicals. This study may be beneficial for the design of more efficient sunlight-driven hybrid photocatalysts and their applications in wastewater treatment.

9.
Environ Res ; 237(Pt 2): 116998, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37634688

RESUMEN

Antibiotics, a kind of containments with the properties of widely distributed and difficult to degrade, has aroused extensive attention in the world. As a prevalent agricultural waste, straws can be utilized to prepare biochar (straw-derived biochar, SBC) to remove antibiotics from aquatic environment. To date, although a number of review papers have summarized and discussed research on biochar application in wastewater treatment and soil remediation, there are few reviews on SBC for antibiotic removal. Due to the limitations of poor adsorption and degradation performance of the pristine SBC, it is necessary to modify SBC to improve its applications for antibiotics removal. The maximum antibiotic removal capacity of modified SBC could reach 1346.55 mg/g. Moreover, the adsorption mechanisms between modified SBC and antibiotics mainly involve π-π interactions, electrostatic interactions, hydrophobic interactions, and charge dipole interactions. In addition, the modified SBC could completely degrade antibiotics within 6 min by activating oxidants, such as PS, PDS, H2O2, and O3. The mechanisms of antibiotic degradation by SBC activated oxidants mainly include free radicals (including SO4•-, •OH, and O2•-) and non-free radical pathway (such as, 1O2, electrons transfer, and surface-confined reaction). Although SBC and modified SBC have demonstrated excellent performance in removing antibiotics, they still face some challenges in practical applications, such as poor stability, high cost, and difficulties in recycling. Therefore, the further research directions and trends for the development of SBC and biochar-based materials should be taken into consideration.

10.
Environ Res ; 234: 116534, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37399983

RESUMEN

Heterogeneous advanced oxidation process has been widely studied as an effective method for removing organic pollutants in wastewater, but the development of efficient catalysts is still challenging. This review summaries the present status of researches on biochar/layered double hydroxides composites (BLDHCs) as catalysts for treatment of organic wastewater. The synthesis methods of layered double hydroxides, the characterizations of BLDHCs, the impacts of process factors influencing catalytic performance, and research advances in various advanced oxidation processes are discussed in this work. The integration of layered double hydroxides and biochar provides synthetic effects for improving pollutant removal. The enhanced pollutant degradation in heterogeneous Fenton, sulfate radical-based, sono-assisted, and photo-assisted processes using BLDHCs have been verified. Pollutant degradation in heterogeneous advanced oxidation processes using BLDHCs is influenced by process factors such as catalyst dosage, oxidant addition, solution pH, reaction time, temperature, and co-existing substances. BLDHCs are promising catalysts due to the unique features including easy preparation, distinct structure, adjustable metal ions, and high stability. Currently, catalytic degradation of organic pollutants using BLDHCs is still in its infancy. More researches should be conducted on the controllable synthesis of BLDHCs, the in-depth understanding of catalytic mechanism, the improvement of catalytic performance, and large-scale application of treating real wastewater.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Hidróxidos , Oxidación-Reducción
11.
J Cutan Med Surg ; 27(5): 504-508, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37533146

RESUMEN

Platelet-rich plasma (PRP) contains a variety of growth factors and has been widely used in maxillofacial surgery, orthopedics, plastic surgery, ophthalmology, and other fields. In recent years, with the increasing morbidity of androgenetic alopecia (AGA), the use of PRP has also increased. The objective of this article was to evaluate the efficacy and safety of PRP for AGA. We searched PubMed, Embase, Web of Science, and Cochrane Library, covering the databases from their earliest records until March 2022. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to explore the effects of PRP for hair density, hair count, and hair diameter in AGA. Nine trials involving 238 patients were included. The meta-analysis showed that PRP for AGA increased hair density at 3 and 6 months with statistically significant differences compared with the placebo (P < .05). PRP also increased hair count and hair diameter compared with the baseline, but there was no significant difference compared with the placebo (P > .05). Two of the 7 studies reported adverse reactions. No serious adverse reactions were found. In conclusion, PRP is an effective and safe treatment for increasing the hair density in AGA. Trial registration: The systematic review was registered with PROSPERO (CRD42022362432).


Asunto(s)
Alopecia , Plasma Rico en Plaquetas , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Alopecia/terapia , Cabello , Resultado del Tratamiento
12.
Molecules ; 28(19)2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37836676

RESUMEN

The purpose of this study was to develop a composite film composed of eugenol Pickering emulsion and pullulan-gelatin, and to evaluate its preservation effect on chilled beef. The prepared composite film was comprehensively evaluated in terms of the stability of emulsion, the physical properties of the film, and an analysis of freshness preservation for chilled beef. The emulsion size (296.0 ± 10.2 nm), polydispersity index (0.457 ± 0.039), and potential (20.1 ± 0.9 mV) proved the success of emulsion. At the same time, the films displayed good mechanical and barrier properties. The index of beef preservation also indicated that eugenol was a better active ingredient than clove essence oil, which led to the rise of potential of hydrogen, chroma and water content, and effectively inhibited microbial propagation, protein degradation and lipid oxidation. These results suggest that the prepared composites can be used as promising materials for chilled beef preservation.


Asunto(s)
Películas Comestibles , Eugenol , Animales , Bovinos , Eugenol/farmacología , Gelatina , Emulsiones , Aceite de Clavo
13.
Angew Chem Int Ed Engl ; 62(33): e202308082, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37358875

RESUMEN

Synthesis of highly active and durable oxygen evolution reaction (OER) catalysts applied in acidic water electrolysis remains a grand challenge. Here, we construct a type of high-loading iridium single atom catalysts with tunable d-band holes character (h-HL-Ir SACs, ∼17.2 wt % Ir) realized in the early OER operation stages. The in situ X-ray absorption spectroscopy reveals that the quantity of the d-band holes of Ir active sites can be fast increased by 0.56 unit from the open circuit to a low working potential of 1.35 V. More remarkably, in situ synchrotron infrared and Raman spectroscopies demonstrate the quick accumulation of *OOH and *OH intermediates over holes-modulated Ir sites in the early reaction voltages, achieving a rapid OER kinetics. As a result, this well-designed h-HL-Ir SACs exhibits superior performance for acidic OER with overpotentials of 216 mV @10 mA cm-2 and 259 mV @100 mA cm-2 , corresponding to a small Tafel slope of 43 mV dec-1 . The activity of catalyst shows no evident attenuation after 60 h operation in acidic environment. This work provides some useful hints for the design of superior acidic OER catalysts.

14.
Small ; 18(27): e2202248, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35678593

RESUMEN

Herein, a strategy of synergetic dual-metal-ion centers to boost transition-metal-based metal organic framework (MOF) alloy nanomaterials as active oxygen reduction reaction (ORR) electrocatalysts for efficient hydrogen peroxide (H2 O2 ) generation is proposed. Through a facile one-pot wet chemical method, a series of MOF alloys with unique Ni-M (M-Co, Cu, Zn) synergetic centers are synthesized, where the strong metallic ions 3d-3d synergy can effectively inhibit O2 cleavage on Ni sites toward a favorable two-electron ORR pathway. Impressively, the well-designed NiZn MOF alloy catalysts show an excellent H2 O2 selectivity up to 90% during ORR, evidently outperforming that of NiCo MOF (45%), and NiCu MOF (55%). Moreover, it sustains efficient activity and robust stability under a continuous longterm ORR operation. The correlative in situ synchrotron radiation X-ray adsorption fine structure and Fourier transform infrared spectroscopy analyses reveal at the atomic level that, the higher Ni oxidation states species, regulated via adjacent Zn2+ ions, are favorable for optimizing the adsorption energetics of key *OOH intermediates toward fast two electron ORR kinetics.

15.
Electrophoresis ; 43(3): 464-471, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34611912

RESUMEN

We developed a low-cost polymer-film spiral inertial microfluidic device for the effective size-dependent separation of malignant tumor cells. The device was fabricated in polymer films by rapid laser cutting and chemical bonding. After fabricating the prototype device, the separation performance of our device was evaluated using particles and cells. The effects of operational flow rate, cell diameter, and cell concentration on the separation performance were explored. Our device successfully separated tumor cells from polydisperse white blood cells according to their different migration modes and lateral positions. Then, the separation of rare cells was carried out using the high-concentration lysed blood spiked with 200 tumor cells. Experimental results showed that 83.90% of the tumor cells could be recovered, while 99.87% of white blood cells could be removed. We successfully employed our device for processing clinical pleural effusion samples from patients with advanced metastatic breast cancer. Malignant tumor cells with an average purity of 2.37% could be effectively enriched, improving downstream diagnostic accuracy. Our device offers the advantages of label-free operation, low cost, and fast fabrication, thus being a potential tool for effective cell separation.


Asunto(s)
Técnicas Analíticas Microfluídicas , Neoplasias , Separación Celular , Humanos , Dispositivos Laboratorio en un Chip , Microfluídica , Polímeros
16.
BMC Biol ; 19(1): 96, 2021 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-33957908

RESUMEN

BACKGROUND: Medicago ruthenica, a wild and perennial legume forage widely distributed in semi-arid grasslands, is distinguished by its outstanding tolerance to environmental stress. It is a close relative of commonly cultivated forage of alfalfa (Medicago sativa). The high tolerance of M. ruthenica to environmental stress makes this species a valuable genetic resource for understanding and improving traits associated with tolerance to harsh environments. RESULTS: We sequenced and assembled genome of M. ruthenica using an integrated approach, including PacBio, Illumina, 10×Genomics, and Hi-C. The assembled genome was 904.13 Mb with scaffold N50 of 99.39 Mb, and 50,162 protein-coding genes were annotated. Comparative genomics and transcriptomic analyses were used to elucidate mechanisms underlying its tolerance to environmental stress. The expanded FHY3/FAR1 family was identified to be involved in tolerance of M. ruthenica to drought stress. Many genes involved in tolerance to abiotic stress were retained in M. ruthenica compared to other cultivated Medicago species. Hundreds of candidate genes associated with drought tolerance were identified by analyzing variations in single nucleotide polymorphism using accessions of M. ruthenica with varying tolerance to drought. Transcriptomic data demonstrated the involvements of genes related to transcriptional regulation, stress response, and metabolic regulation in tolerance of M. ruthenica. CONCLUSIONS: We present a high-quality genome assembly and identification of drought-related genes in the wild species of M. ruthenica, providing a valuable resource for genomic studies on perennial legume forages.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Medicago , Sequías , Medicago/genética , Medicago sativa/genética , Estrés Fisiológico/genética
17.
Angew Chem Int Ed Engl ; 61(2): e202110838, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34716639

RESUMEN

Accurately regulating the selectivity of the oxygen reduction reaction (ORR) is crucial to renewable energy storage and utilization, but challenging. A flexible alteration of ORR pathways on atomically dispersed Zn sites towards high selectivity ORR can be achieved by tailoring the coordination environment of the catalytic centers. The atomically dispersed Zn catalysts with unique O- and C-coordination structure (ZnO3 C) or N-coordination structure (ZnN4 ) can be prepared by varying the functional groups of corresponding MOF precursors. The coordination environment of as-prepared atomically dispersed Zn catalysts was confirmed by X-ray absorption fine structure (XAFs). Notably, the ZnN4 catalyst processes a 4 e- ORR pathway to generate H2 O. However, controllably tailoring the coordination environment of atomically dispersed Zn sites, ZnO3 C catalyst processes a 2 e- ORR pathway to generate H2 O2 with a near zero overpotential and high selectivity in 0.1 M KOH. Calculations reveal that decreased electron density around Zn in ZnO3 C lowers the d-band center of Zn, thus changing the intermediate adsorption and contributing to the high selectivity towards 2 e- ORR.

18.
Small ; 17(49): e2105231, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34713574

RESUMEN

Accurately manipulating the electronic structure of metal active sites under working conditions is central to developing efficient and stable electrocatalysts in industrial water-alkali electrolyzers. However, the lack of an intuitive means to capture the evolution of metal sites during the reaction state inhibits the manipulation of its electronic structure. Here, atomically dispersed Ru single-sites on cobalt nanoparticles confined onto macro-microporous frameworks (M-Co NPs@Ru SAs/NC) with tunable electron coupling effect for efficient catalysis of alkaline hydrogen evolution reaction (HER) are constructed. Using operando X-ray absorption and infrared spectroscopies, a dynamic CoRu bond shrinkage with strong electron coupling effect under working conditions is identified, which significantly promotes the adsorption of water molecules and then accelerates its dissociation to form the key H* over Ru sites for high HER activity. The well-designed M-Co NPs@Ru SAs/NC delivers efficient HER performance with a small overpotential of 34 mV at 10 mA cm-2 and a high turnover frequency of ≈4284 H2  h-1 at -0.05 V, 40 times higher than that of the benchmark Pt/C. This work provides a new point of view to manipulate the electronic structure of the metal active sites for highly effective electrocatalysis processes.

19.
J Exp Bot ; 72(10): 3504-3512, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33587748

RESUMEN

Plant cells contain two types of vacuoles, the lytic vacuole (LV) and protein storage vacuole (PSV). LVs are present in vegetative cells, whereas PSVs are found in seed cells. The physiological functions of the two types of vacuole differ. Newly synthesized proteins must be transported to these vacuoles via protein trafficking through the endomembrane system for them to function. Recently, significant advances have been made in elucidating the molecular mechanisms of protein trafficking to these organelles. Despite these advances, the relationship between the trafficking mechanisms to the LV and PSV remains unclear. Some aspects of the trafficking mechanisms are common to both types of vacuole, but certain aspects are specific to trafficking to either the LV or PSV. In this review, we summarize recent findings on the components involved in protein trafficking to both the LV and PSV and compare them to examine the extent of overlap in the trafficking mechanisms. In addition, we discuss the interconnection between the LV and PSV provided by the protein trafficking machinery and the implications for the identity of these organelles.


Asunto(s)
Semillas , Vacuolas , Células Vegetales/metabolismo , Proteínas de Plantas/metabolismo , Transporte de Proteínas , Semillas/metabolismo , Vacuolas/metabolismo
20.
J Clin Lab Anal ; 35(11): e24018, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34550610

RESUMEN

BACKGROUND: Lung adenocarcinoma (LUAD) is the leading cause of cancer-related deaths worldwide. Therefore, the identification of a novel prediction signature for predicting the prognosis risk and survival outcomes is urgently demanded. METHODS: We integrated a machine-learning frame by combing the Cox regression and Least Absolute Shrinkage and Selection Operator (LASSO) regression model to identify the LUAD-related long non-coding RNA (lncRNA) survival biomarkers. Subsequently, the Spearman correlation test was employed to interrogate the relationships between lncRNA signature and tumor immunity and constructed the competing endogenous RNA (ceRNA) network. RESULTS: Herein, we identified an eight-lncRNA signature (PR-lncRNA signature, NPSR1-AS1, SATB2-AS1, LINC01090, FGF12-AS2, AC005256.1, MAFA-AS1, BFSP2-AS1, and CPC5-AS1), which contributes to predicting LUAD patient's prognosis risk and survival outcomes. The PR-lncRNA signature has also been confirmed as the robust signature in independent datasets. Further parsing of the LUAD tumor immune infiltration showed the PR-lncRNAs were closely associated with the abundance of multiple immune cells infiltration and the expression of MHC molecules. Furthermore, by constructing the PR-lncRNA-related ceRNA network, we interrogated more potential anti-cancer therapy targets. CONCLUSION: lncRNAs, as emerging cancer biomarkers, play an important role in a variety of cancer processes. Identification of PR-lncRNA signatures allows us to better predict patient's survival outcomes and disease risk. Finally, the PR-lncRNA signatures could help us to develop novel LUAD anti-cancer therapeutic strategies.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , ARN Largo no Codificante , Adenocarcinoma del Pulmón/diagnóstico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/mortalidad , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Aprendizaje Automático , Pronóstico , ARN Largo no Codificante/análisis , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Transcriptoma/genética
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