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1.
Angew Chem Int Ed Engl ; 59(34): 14577-14583, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32495999

RESUMO

Aqueous zinc (Zn) batteries have been considered as promising candidates for grid-scale energy storage. However, their cycle stability is generally limited by the structure collapse of cathode materials and dendrite formation coupled with undesired hydrogen evolution on the Zn anode. Herein we propose a zinc-organic battery with a phenanthrenequinone macrocyclic trimer (PQ-MCT) cathode, a zinc-foil anode, and a non-aqueous electrolyte of a N,N-dimethylformamide (DMF) solution containing Zn2+ . The non-aqueous nature of the system and the formation of a Zn2+ -DMF complex can efficiently eliminate undesired hydrogen evolution and dendrite growth on the Zn anode, respectively. Furthermore, the organic cathode can store Zn2+ ions through a reversible coordination reaction with fast kinetics. Therefore, this battery can be cycled 20 000 times with negligible capacity fading. Surprisingly, this battery can even be operated in a wide temperature range from -70 to 150 °C.

2.
Chemistry ; 24(41): 10310-10314, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-29736950

RESUMO

Crossover of liquid fuel remains a severe problem for conventional direct liquid fuel cells even when polymer electrolyte membranes are applied. Herein, we report for the first time a membrane-free direct liquid fuel cell powered by alkaline hypophosphite solution. The proof-of-concept fuel cell yields a peak power density of 32 mW cm-2 under air flow at room temperature. The removal of the polymer electrolyte membrane is attributed to the high reactivity and selectivity of Pd and α-MnO2 towards the hypophosphite oxidation on the anode and oxygen reduction on the cathode, respectively. The discharge products are analyzed by 31 P NMR spectroscopy and the faradaic efficiencies have been calculated after discharging at 10 mA cm-2 for 20 hours. The non-toxicity of hypophosphite and membrane-free fuel cell structure provide huge potential for future applications.

3.
Zoolog Sci ; 31(8): 529-34, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25088594

RESUMO

Characterization of foraging-site preferences of threatened and endangered species is a key component of effective habitat conservation. We studied foraging-site selection by the brown eared pheasant (Crossoptilon mantchuricum) in the Huanglongshan Nature Reserve, Yanan City, Shaanxi Province, China, from early February to end of May 2011. We identified feeding sites by locating tracks and scratches characteristic of the birds, and compared habitat characteristics at these sites to those at randomly selected sites across the study area. During the pre-breeding season, the birds tended to be found in the areas characterized by gullies within mixed forests with intermediate sun exposure on gentle slopes (< 10°), and close to water and footpaths. The sites utilized by the birds also featured greater tree diameter, lower shrub density, lower grass cover, and lower altitude than random sites. During the breeding season, the birds tended to be found in the areas of slightly higher altitude, more shrubs, moderately steep slopes (10°-20°), and farther from water and paths. These patterns were consistent with seasonal changes in vegetation and food-resource availability in the study area. Management of brown eared pheasants' populations for conservation must account for these seasonal shifts in habitat requirements.


Assuntos
Ecossistema , Galliformes/fisiologia , Estações do Ano , Animais , China , Demografia , Reprodução/fisiologia
5.
ISME J ; 17(3): 417-431, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36627434

RESUMO

Migration from rhizosphere to rhizoplane is a key selecting process in root microbiome assembly, but not fully understood. Rhizobiales members are overrepresented in the core root microbiome of terrestrial plants, and here we report a genome-wide transposon-sequencing of rhizoplane fitness genes of beneficial Sinorhizobium fredii on wild soybean, cultivated soybean, rice, and maize. There were few genes involved in broad-host-range rhizoplane colonization. The fadL mutant lacking a fatty acid transporter exhibited high colonization rates, while mutations in exoFQP (encoding membrane proteins directing exopolysaccharide polymerization and secretion), but not those in exo genes essential for exopolysaccharide biosynthesis, led to severely impaired colonization rates. This variation was not explainable by their rhizosphere and rhizoplane survivability, and associated biofilm and exopolysaccharide production, but consistent with their migration ability toward rhizoplane, and associated surface motility and the mixture of quorum-sensing AHLs (N-acylated-L-homoserine lactones). Genetics and physiology evidences suggested that FadL mediated long-chain AHL uptake while ExoF mediated the secretion of short-chain AHLs which negatively affected long-chain AHL biosynthesis. The fadL and exoF mutants had elevated and depleted extracellular long-chain AHLs, respectively. A synthetic mixture of long-chain AHLs mimicking that of the fadL mutant can improve rhizobial surface motility. When this AHL mixture was spotted into rhizosphere, the migration toward roots and rhizoplane colonization of S. fredii were enhanced in a diffusible way. This work adds novel parts managing extracellular AHLs, which modulate bacterial migration toward rhizoplane. The FadL-ExoFQP system is conserved in Alphaproteobacteria and may shape the "home life" of diverse keystone rhizobacteria.


Assuntos
Rhizobium , Bactérias/genética , Percepção de Quorum , Biofilmes , Ácidos Graxos , Acil-Butirolactonas/metabolismo
6.
Medicine (Baltimore) ; 101(52): e31773, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36596052

RESUMO

Yixue Qiyuan is a representative work of Yuansu Zhang, a famous medical scientist during the Jin Dynasty. The contents of Five Yun and Six Qi are quite rich, especially the discussion on the treatment prescription and medication of Six Qi, which has a significant impact on the development of traditional Chinese medicine. Therefore, analyzing his drug rules and summarizing his medical thoughts can provide a reference for the clinical application of the theory of Five Yun and Six Qi. Based on the TCM inheritance auxiliary platform (V2.5), the data analyzed 63 first prescriptions and 134 drugs contained in the six Qi prescription sections of Yixue Qiyuan. Based on the frequency analysis, correlation rule analysis, four qi and five flavors, and meridian analysis, the formula rules for wind, summer heat, wet soil, fire, dryness, and cold water were obtained, and medical thought was summarized. Drug rules of prescription and medical thought can provide a useful reference for the classical study of traditional Chinese medicine and the application of the Six Qi theory in clinical practice.


Assuntos
Prescrições de Medicamentos , Qi , Humanos , Medicina Tradicional Chinesa , Meridianos
7.
Cell Stress Chaperones ; 27(4): 325-336, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35366755

RESUMO

Acute kidney injury (AKI) induced by cisplatin (cis-AKI) involves indicators such as inflammation and oxidative stress (OS) in proximal tubules, although its underlying mechanisms remain largely unknown so far. Exploration of the molecular mechanisms underlying cisplatin-induced AKI is of great significance for AKI prevention and also for preventing its progression into chronic kidney disease (CKD) or end-stage renal disease (ESRD). OS and ferroptosis are mutually causal; they finally lead to the regulatory cell injury and death induced by the accumulation of reactive oxygen species (ROS). GPX4 is critical not only in OS, but studies established as the key regulator of ferroptosis. In this context, the present study focused on determining the biological function of miR-214-3p in the cisplatin-induced ferroptosis of tubular epithelial cell (TEC) and the underlying molecular mechanism. The relationship between TEC ferroptosis and cisplatin-induced AKI was investigated in vitro and in vivo. Ferrostatin-1(Fer-1), an inhibitor of ferroptosis, was observed to confer a protective effect against the renal tubular injury and renal failure induced by cisplatin. MicroRNAs (miRNAs) regulate the genes that have important functions in the development of cis-AKI. In the present study, GPX4 was predicted as a target of miR-214-3p. Moreover, inhibiting miR-214-3p enhanced the expressions of GPX4 and SLC7A11 while decreasing the ACSL4 expression. Furthermore, miR-214-3p down-regulation protected against TEC death and renal tubule damage both in vitro and in vivo. According to these findings, inhibiting miR-214-3p would alleviate TEC ferroptosis in cis-AKI via GPX4.


Assuntos
Injúria Renal Aguda , Ferroptose , MicroRNAs , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/genética , Animais , Cisplatino/toxicidade , Túbulos Renais Proximais/metabolismo , Camundongos , MicroRNAs/genética , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética
8.
Front Physiol ; 11: 906, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903383

RESUMO

Renal ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI). As a transcription factor, the Transcript induced in spermiogenesis 40 (Tisp40) has been found to be involved in renal IRI. However, the role of Tisp40 in tubular epithelial cell (TEC) pyroptosis of renal IRI remains unknown. In this study, we investigated effects of Tisp40 on Gasdermin D (GSDMD)-mediated TEC pyroptosis in renal IRI and underlying molecular mechanisms in I/R-induced kidney by hematoxylin and eosin (HE) staining, Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay,immunohistochemistry (IHC), reverse transcription-quantitative PCR (RT-qPCR) and western blot analysis in vivo and oxygen-glucose deprivation/reoxygenation (OGD/R)-stimulated TCMK-1 cells by lactate dehydrogenase (LDH) release assay, CCK-8 assay,enzyme-linked immunosorbent assay (ELISA), flow cytometric analysis, immunofluorescence staining,RT-qPCRand western blot analysis in vitro. We found that the levels of Tisp40 and GSDMD-N expression increased gradually, and peaked at 30 min ischemia/24 h reperfusion in vivo and 24 h OGD/R/6 h reoxygenation in vitro, simultaneously, the levels of TEC pyroptosis and renal injury were correspondingly increased. The data of Pearson's correlation analysis showed that the expression of Tisp40 and GSDMD-N was positively correlated. Furthermore, Tisp40 overexpression aggravated TEC pyroptosis rate and increased the expressions of related proteins, including GSDMD-N, NLRP3, caspase-1, IL-1ß, and IL-18 in the OGD/R-stimulated TCMK-1 cell line, whereas the opposite occurred in cells treated with small interfeing RNA (siRNA) targeting Tisp40. Tisp40-deficient mice showed attenuated renal IRI and pyroptosis compared with wild-type mice. In addition, Tisp40 knockout remarkably decreased the levels of GSDMD-N, IL-1ß, IL-18, NLRP3, and caspase-1 expression, and alleviated renal pyroptosis induced by I/R. Importantly, Tisp40 overexpression significantly increased TECs pyroptosis via p-p65 activation, however, the effects of Tisp40 overexpression were partially blocked by parthenolide (PTL). Collectively, our findings provide insight into the mechanism of how Tisp40 regulated GSDMD-mediated pyroptosis in renal IRI.

9.
Front Genet ; 11: 616947, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33505436

RESUMO

Renal ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI) and has no effective treatment. Exploring the molecular mechanisms of renal IRI is critical for the prevention of AKI and its evolution to chronic kidney disease and end-stage renal disease. The aim of the present study was to determine the biological function and molecular mechanism of action of miR-92a-3p in tubular epithelial cell (TEC) pyroptosis. We investigated the relationship between nuclear factor-erythroid 2-related factor 1 (Nrf1) and TEC pyroptosis induced by ischemia-reperfusion in vivo and oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro. MicroRNAs (miRNAs) are regulators of gene expression and play a role in the progression of renal IRI. Nrf1 was confirmed as a potential target for miRNA miR-92a-3p. In addition, the inhibition of miR-92a-3p alleviated oxidative stress in vitro and decreased the expression levels of NLRP3, caspase-1, GSDMD-N, IL-1ß, and IL-18 in vitro and in vivo. Moreover, Zn-protoporphyrin-IX, an inhibitor of heme oxygenase-1, reduced the protective effect of Nrf1 overexpression on OGD/R-induced TEC oxidative stress and pyroptosis. The results of this study suggest that the inhibition of miR-92a-3p can alleviate TEC oxidative stress and pyroptosis by targeting Nrf1 in renal IRI.

10.
Research (Wash D C) ; 2019: 7481319, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31912045

RESUMO

The lithium- (Li-) metal anode is crucial for developing high-energy-density batteries, while its dendritic growth and the low charge/discharge Coulombic efficiency in organic electrolytes hinder its practical application. Herein, we employed an in situ optical microscope to investigate the effect of the electrolyte concentration and the working temperature on the Li-plating/-stripping process. It is found that a higher concentration electrolyte can suppress its side reaction to improve the charge/discharge Coulombic efficiency, and a higher temperature can help lithium plate/strip uniformly with less lithium dendritic growth. An average Coulombic efficiency was obtained as high as 99.2% for over 150 cycles with a fixed plating capacity of 2 mAh cm-2 on copper foil in a 3 mol/kg ether-based electrolyte under 60°C, which provides an efficient and facile strategy for developing high-performance Li-metal batteries.

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