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1.
Small ; 20(13): e2306697, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37963857

RESUMO

Bismuth chalcogenides are used as cathode materials in Zn-proton hybrid ion batteries, which exhibit an ultraflat discharge plateau that is favorable for practical applications. Unfortunately, their capacity is not competitive, and their charge storage mechanisms are ambiguous, both of which hinder their further development. In this study, S-doped Bi2Te3- x (SBT) nanosheets are prepared by tellurizing a Bi2O2S precursor using a hydrothermal process. As revealed by density functional theory analyses, the S dopant and its induced Te vacancies can distinctly manipulate the electronic structure of SBT, resulting in decent electrical conductivity and more negative adsorption energy to Zn2+. These advantages boost the Zn2+ storage ability of SBT materials. Consequently, compared with defect-free Bi2Te3, the SBT cathodes have superior specific capacity, rate capability, and cycling stability.

2.
Nature ; 564(7734): 119-124, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30455424

RESUMO

Haematopoietic stem and progenitor cells (HSPCs) give rise to all blood lineages that support the entire lifespan of vertebrates1. After HSPCs emerge from endothelial cells within the developing dorsal aorta, homing allows the nascent cells to anchor in their niches for further expansion and differentiation2-5. Unique niche microenvironments, composed of various blood vessels as units of microcirculation and other niche components such as stromal cells, regulate this process6-9. However, the detailed architecture of the microenvironment and the mechanism for the regulation of HSPC homing remain unclear. Here, using advanced live imaging and a cell-labelling system, we perform high-resolution analyses of the HSPC homing in caudal haematopoietic tissue of zebrafish (equivalent to the fetal liver in mammals), and reveal the role of the vascular architecture in the regulation of HSPC retention. We identify a VCAM-1+ macrophage-like niche cell population that patrols the inner surface of the venous plexus, interacts with HSPCs in an ITGA4-dependent manner, and directs HSPC retention. These cells, named 'usher cells', together with caudal venous capillaries and plexus, define retention hotspots within the homing microenvironment. Thus, the study provides insights into the mechanism of HSPC homing and reveals the essential role of a VCAM-1+ macrophage population with patrolling behaviour in HSPC retention.


Assuntos
Células Endoteliais/citologia , Células-Tronco Hematopoéticas/citologia , Macrófagos/metabolismo , Nicho de Células-Tronco , Molécula 1 de Adesão de Célula Vascular/metabolismo , Animais , Diferenciação Celular , Movimento Celular , Microambiente Celular , Integrinas/genética , Integrinas/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
3.
Int J Mol Sci ; 20(6)2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30901819

RESUMO

Boron (B) toxicity in Citrus is a common physiological disorder leading to reductions in both productivity and quality. Studies on how Citrus roots evade B toxicity may provide new insight into plant tolerance to B toxicity. Here, using Illumina sequencing, differentially expressed microRNAs (miRNAs) were identified in B toxicity-treated Citrus sinensis (tolerant) and C. grandis (intolerant) roots. The results showed that 37 miRNAs in C. grandis and 11 miRNAs in C. sinensis were differentially expressed when exposed to B toxicity. Among them, miR319, miR171, and miR396g-5p were confirmed via 5'-RACE and qRT-PCR to target a myeloblastosis (MYB) transcription factor gene, a SCARECROW-like protein gene, and a cation transporting ATPase gene, respectively. Maintenance of SCARECROW expression in B treated Citrus roots might fulfill stem cell maintenance, quiescent center, and endodermis specification, thus allowing regular root elongation under B-toxic stress. Down-regulation of MYB due to up-regulation of miR319 in B toxicity-treated C. grandis roots might decrease the number of root tips, thereby dramatically changing root system architecture. Our findings suggested that miR319 and miR171 play a pivotal role in Citrus adaptation to long-term B toxicity by targeting MYB and SCARECROW, respectively, both of which are responsible for root growth and development.


Assuntos
Adaptação Biológica , Boro/metabolismo , Citrus/fisiologia , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Desenvolvimento Vegetal/genética , Raízes de Plantas/fisiologia , Boro/toxicidade , Citrus/classificação , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Fenótipo , Filogenia , Interferência de RNA
4.
Cell Mol Gastroenterol Hepatol ; 18(1): 41-52, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38461963

RESUMO

Alcohol-associated liver disease (ALD) is a major contributor to liver-related mortality globally. An increasing body of evidence underscores the pivotal role of platelets throughout the spectrum of liver injury and recovery, offering unique insights into liver homeostasis and pathobiology. Alcoholic-associated steatohepatitis is characterized by the infiltration of hepatic neutrophils. Recent studies have highlighted the extensive distance neutrophils travel through sinusoids to reach the liver injury site, relying on a platelet-paved endothelium for efficient crawling. The adherence of platelets to neutrophils is crucial for accurate migration from circulation to the inflammatory site. A gradual decline in platelet levels leads to diminished neutrophil recruitment. Platelets exhibit the ability to activate neutrophils. Platelet activation is heightened upon the release of platelet granule contents, which synergistically activate neutrophils through their respective receptors. The sequence culminates in the formation of platelet-neutrophil complexes and the release of neutrophil extracellular traps intensifies liver damage, fosters inflammatory immune responses, and triggers hepatotoxic processes. Neutrophil infiltration is a hallmark of alcohol-associated steatohepatitis, and the roles of neutrophils in ALD pathogenesis have been studied extensively, however, the involvement of platelets in ALD has received little attention. The current review consolidates recent findings on the intricate and diverse roles of platelets and neutrophils in liver pathophysiology and in ALD. Potential therapeutic strategies are highlighted, focusing on targeting platelet-neutrophil interactions and activation in ALD. The anticipation is that innovative methods for manipulating platelet and neutrophil functions will open promising avenues for future ALD therapy.


Assuntos
Plaquetas , Hepatopatias Alcoólicas , Neutrófilos , Humanos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Plaquetas/metabolismo , Plaquetas/patologia , Hepatopatias Alcoólicas/patologia , Hepatopatias Alcoólicas/imunologia , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/etiologia , Animais , Infiltração de Neutrófilos , Fígado/patologia , Fígado/imunologia , Fígado/metabolismo , Comunicação Celular , Ativação Plaquetária
5.
Front Plant Sci ; 13: 856937, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646029

RESUMO

The substrate pH directly affects nutrient availability in the rhizosphere and nutrient uptake by plants. Macronutrients such as nitrogen, potassium, calcium, magnesium, and sulfur are highly available at pH 6.0-6.5, while micronutrients become less available at higher, alkaline pH (pH > 7.0). Recent research has indicated that low pHs can enhance nutrient uptake and improve sweet orange (Citrus sinensis) tree health. We designed a study to understand the influence of a wide range of substrate pH values on plant size and biomass, nutrient availability, leaf gas exchange, and rhizosphere microbiome of grapefruit (Citrus paradisi) affected by Huanglongbing (HLB). Two-year-old "Ray Ruby" grapefruit plants grafted on sour orange (Citrus aurantium) rootstock were cultivated indoors in 10-cm wide × 40-cm tall pots with peat:perlite commercial substrate (80:20 v/v). We tested two disease statuses [HLB-free or healthy (negative, HLB-) and HLB-affected (positive, HLB+)] and six substrate pH values (4, 5, 6, 7, 8, 9) in a 2 × 6 factorial arranged on a complete randomized design with four replications. The canopy volume of HLB+ plants was 20% lower than healthy plants, with pHs 7 and 9 resulting in 44% less canopy volume. The root and shoot ratio of dry weight was 25.8% lower in HLB+ than in healthy plants. Poor root growth and a decrease in fibrous roots were found, especially in pH 5 and 6 treatments in HLB+ plants (p < 0.0001). The disease status and the substrate pHs influenced the leaf nutrient concentration (p < 0.05). High substrate pH affects nutrient availability for root uptake, influencing the nutrient balance throughout the plant system. pH values did not affect plant photosynthesis, indicating that pH does not recover HLB+ plants to the photosynthetic levels of healthy plants-even though high pH positively influenced internal CO2. There were collectively over 200 rhizobacterial identified by the 16S rRNA gene sequencing in individual phylogenetic trees. Most rhizobacteria reads were identified in pH 9. Our results indicated no effect of substrate pHs on the plant disease status induced by enhanced nutrient uptake.

6.
Biosci Rep ; 39(7)2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31285388

RESUMO

Many studies have demonstrated the effects of statin therapy on platelet, but it is controversial that whether statin could reduce mean platelet volume (MPV) in patients with the risk of cardiovascular diseases. To further improve the clinical significance of MPV in those patients and explore new function of statin, we conducted this research. Relevant studies were selected by searching electronic databases (PubMed, Embase and Cochrane Library) and reference lists of related articles by hand. Two reviewers independently assessed eligibility and quality of the studies. Eventually, we included ten studies, a total of 1189 patients with the risk of cardiovascular diseases. Consolidating relevant data and comparing the changes of MPV before and after statin treatment, we found that statin could decrease MPV [standard mean difference (SMD) = -0.47 (-0.71-0.23)], which was statistically significant (P=0.0001). Subgroup analysis suggested that when ≥55 years, this decrease did not occur [SMD = -0.06 (-0.18, 0.06)]. Drug type, sample size, ethnicity, mean age and quality of included article were sources of heterogeneity. Therefore, statin therapy could reduce MPV significantly and exhibited antiplatelet activity, which is of great importance in clarifying the clinical significance of MPV in cardiovascular events and the prevention of cardiovascular events.


Assuntos
Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Volume Plaquetário Médio , Feminino , Humanos , Masculino , Fatores de Risco
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