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1.
Mol Breed ; 44(6): 38, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38766511

RESUMO

Cotton fibers are specialized single-cell trichomes derived from epidermal cells, similar to root hairs and trichomes in Arabidopsis. While the MYB-bHLH-WD40 (MBW) complex has been shown to regulate initiation of both root hairs and trichomes in Arabidopsis, the role of their homologous gene in cotton fiber initiation remains unknown. In this study, we identified a R2R3 MYB transcription factor (TF), GhWER, which exhibited a significant increase in expression within the outer integument of ovule at -1.5 DPA (days post anthesis). Its expression peaked at -1 DPA and then gradually decreased. Knockout of GhWER using CRISPR technology inhibited the initiation and early elongation of fiber initials, resulting in the shorter mature fiber length. Additionally, GhWER interacted with two bHLH TF, GhDEL65 and GhbHLH121, suggesting a potential regulatory complex for fiber development. RNA-seq analysis of the outer integument of the ovule at -1.5 DPA revealed that the signal transduction pathways of ethylene, auxin and gibberellin were affected in the GhWER knockout lines. Further examination demonstrated that GhWER directly activated ethylene signaling genes, including ACS1 and ETR2. These findings highlighted the biological function of GhWER in regulating cotton fiber initiation and early elongation, which has practical significance for improving fiber quality and yield. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01477-6.

2.
Analyst ; 148(12): 2725-2731, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37232137

RESUMO

To improve the peroxidase-like activities of metal-organic frameworks (MOFs) as nanozymes, a ternary MIL-100(Fe)@PMo12@3DGO nanocomposite was designed and fabricated by encapsulating Keggin-type H3PMo12O40 (PMo12) with fast and reversible multi-electron redox processes and an electron-rich structure into MIL-100(Fe), then being covered by three-dimensional graphene (3DGO) with higher conductivity, larger surface area, higher porosity, and better chemical stability. As a consequence, the as-prepared MIL-100(Fe)@PMo12@3DGO nanocomposite exhibits excellent peroxidase-like activities, namely, the lowest limit of detection (0.14 µM) in the range of 1-100 µM for glucose to date, to the best of our knowledge, attributed to the individual and synergistic effects of H3PMo12O40, 3DGO and MIL-100(Fe).

3.
Inorg Chem ; 62(7): 3134-3140, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36753423

RESUMO

How to overcome the problem of fast capacity fading and low sulfur utilization is the key to promote the practical applications of lithium-sulfur (Li-S) batteries. Based on the fact that sulfur-functionalized graphene oxide (GO-S) can avoid the loss of sulfur/polysulfides through the strong C-S interaction, and the zeolitic imidazolate framework (ZIF-67) can capture sulfur and catalyze lithium polysulfide (Li2Sx, 4 ≤ x ≤ 8), the combination of ZIF-S (ZIF-67 after combining with sulfur) with GO-S can be expected to be an excellent electrode material for Li-S batteries due to the synergistic effect. Herein, ZIF-S@GO-S (n) nanocomposites (n = 1, 2, and 3 for the mass ratio of ZIF-67/GO of 4:1, 6:1, and 8:1, respectively) as the cathode materials in Li-S batteries were successfully fabricated, and ZIF-S@GO-S (2) showed better electrochemical performances and cycle stability with a high specific capacity of 1529.5 mA h g-1 at the initial cycle and 792 mA h g-1 after 500 cycles at 0.1 C (1 C = 1675 mA h g-1). The fact that ZIF-S@GO-S (n) can simultaneously improve the conductivity and utilization of S (C-S···S8 and C-S···SxLi2) and the conversion kinetics of Li2Sx (4 ≤ x ≤ 8) provides a new avenue for designing and fabricating promising cathodes for high-performance Li-S batteries.

4.
Acta Trop ; 240: 106844, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36706827

RESUMO

Blastocystis is an enteric protozoan able to infect humans and a large variety of animal hosts worldwide. It exhibits significant genetic diversity, with at least 17 subtypes (STs) identified to date, most of which have low host specificity. In the present study, a cross-sectional survey was conducted on Blastocystis infection among humans and domestic animals sharing habitats in northeastern China's Heilongjiang Province, in order to investigate the frequency and subtype distribution and to evaluate the risk of the zoonotic transmission of Blastocystis sp..Results show that the frequency was 10.5% (6/57), and three subtypes (ST1, ST2, and ST3) were found in humans; in animals, the frequency was 17.9% (46/257), and six subtypes (ST1, ST3, ST5, ST7, ST10, and ST26) were detected. A significant association between Blastocystis sp. infection and eating unwashed vegetables and fruits was found (P = 0.007). We found no effect on gender, age and season on Blastocystis sp. colonization. Phylogenetic analysis showed that Blastocystis ST7 sequences from chicken in two geographical locations formed two distinct clades. Alleles were identified using the Blastocystis 18S database, and a total of 10 different alleles were found in seven STs. Overlap of STs in humans and domestic animals (pig or cattle) was observed in Dongfanghong village. The findings of potentially zoonotic subtypes in domestic animals suggest that these animals may serve as reservoirs of human Blastocystis sp. infections. Multisectoral cooperation is needed to slow down the transmission of Blastocystis in domestic animals, minimize environmental contamination by Blastocystis cysts, and increase molecular epidemiological surveillance of Blastocystis sp. in humans and animals.


Assuntos
Infecções por Blastocystis , Blastocystis , Humanos , Animais , Bovinos , Suínos , Blastocystis/genética , Animais Domésticos , Filogenia , Estudos Transversais , Variação Genética , Infecções por Blastocystis/veterinária , China/epidemiologia , Fezes , Prevalência
5.
Int J Biol Macromol ; 231: 123289, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36657545

RESUMO

This paper reports the preparation of calcium alginate gels-functionalized PUF decorated with AgNPs (CA/PUF@Ag) by in situ reduction of Ag+ ions to form AgNPs with weakly reducing glycerol in CA/PUF composite. The water-adsorbing capacity, chemical structure, crystalline nature, elemental composition and morphologies of the composite were characterized. The Ag release behavior of CA/PUF@Ag was investigated. The inhibition zone test, time-dependent co-culture assay, test tube test, and antibacterial filtration experiment with Escherichia coli as an indicator of bacterial contamination were conducted to explore the antimicrobial efficacy. Results indicated that the CA/PUF@Ag prepared at 0.25 % w/v of SA could absorb more water with a higher swelling ratio of 8.0 g/g than that of PUF@Ag (6.0 g/g), which was subsequently squeezed by minimal pressure stimuli. The CA/PUF@Ag had a larger initial AgNPs loading amount (8.48 mg/g), lower Ag release concentration (44.35 µg/L) and lower Ag release rate (0.27 %) after 14 days tests than those of PUF@Ag (7.93 mg/g, 80.87 µg/L and 0.60 % respectively). The CA/PUF@Ag was highly reusable because bacterial cells in the squeezed water recovered from the composite were completely inactivated over five cycles of operation, and exhibited good antibacterial efficacy as an antibacterial filter in a flow test.


Assuntos
Nanopartículas Metálicas , Água , Desinfecção/métodos , Prata/química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Escherichia coli , Géis
6.
Plant Biotechnol J ; 20(12): 2372-2388, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36053965

RESUMO

Cotton fibre is a unicellular seed trichome, and lint fibre initials per seed as a factor determines fibre yield. However, the mechanisms controlling fibre initiation from ovule epidermis are not understood well enough. Here, with single-cell RNA sequencing (scRNA-seq), a total of 14 535 cells were identified from cotton ovule outer integument of Xu142_LF line at four developmental stages (1.5, 1, 0.5 days before anthesis and the day of anthesis). Three major cell types, fibre, non-fibre epidermis and outer pigment layer were identified and then verified by RNA in situ hybridization. A comparative analysis on scRNA-seq data between Xu142 and its fibreless mutant Xu142 fl further confirmed fibre cluster definition. The developmental trajectory of fibre cell was reconstructed, and fibre cell was identified differentiated at 1 day before anthesis. Gene regulatory networks at four stages revealed the spatiotemporal pattern of core transcription factors, and MYB25-like and HOX3 were demonstrated played key roles as commanders in fibre differentiation and tip-biased diffuse growth respectively. A model for early development of a single fibre cell was proposed here, which sheds light on further deciphering mechanism of plant trichome and the improvement of cotton fibre yield.


Assuntos
Fibra de Algodão , Gossypium , Gossypium/genética , RNA-Seq , Tricomas/genética , Óvulo Vegetal/genética
7.
Chemistry ; 28(20): e202200207, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35229378

RESUMO

To address the poor cycling stability and low rate capability of MoS2 as electrode materials for lithium-ion batteries (LIBs), herein, the CoS2 /MoS2 /PDDA-rGO/PMo12 nanocomposites are constructed via a simple hydrothermal process, combining the advantages of all three, namely, CoS2 /MoS2 heterojunction and polyoxometalates (POMs) provide abundant catalytically active sites and increase the multi-electron transfer ability, and the positively charged poly(diallyldimethylammonium chloride) modified reduced graphene oxide (PDDA-rGO) improve electronic conductivity and effectively prevent the aggregation of MoS2 , meanwhile stabilize the negatively charged [PMo12 O40 ]3- . After the electrochemical testing, the resulting CoS2 /MoS2 /PDDA-rGO/PMo12 nanocomposite achieved 1055 mA h g-1 initial specific capacities and stabilized at 740 mA h g-1 after 150 cycles at 100 mA g-1 current density. And the specific capacities of MoS2 , MoS2 /PDDA-rGO, CoS2 /MoS2 , and CoS2 /MoS2 /PDDA-rGO were 201, 421, 518, and 589 at 100 mA g-1 after 150 cycles, respectively. The fact of the greatly improving capacity of MoS2 -based nanocomposites suggests its potential for high performance electrode materials of LIBs. Moreover, the lithium storage mechanism of CoS2 /MoS2 /PDDA-rGO/PMo12 has been discussed on the basis of cyclic voltammetry with different scan rates.

8.
Chemistry ; 28(22): e202104213, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35212424

RESUMO

Introducing the idea of integrated design and cascade activity into nanozyme, the novel integrated nanozymes (INAzymes), FeMo6 @Ce-Uio-66 (FC-66(n)), were designed and synthesized by encapsulating iron-based polyoxometalates (FeMo6 ) into the ceria-based metal-organic framework (Ce-Uio-66). Due to the oxygen-driven reversible Ce3+ /Ce4+ couple sites, the "Fenton-like" effect by iron centers, the "nanoscale proximity" effects by nanocages, and their synergistic effects, FC-66(n) as INAzymes exhibit elegant cascade enzyme-mimic activities (oxidase-, peroxidase-, and Fenton-like activity), which realizes INAzyme activities based on polyoxometalates based metal-organic framework (POMOFs). By employing dopamine (DA) detection as a model reaction, a high-efficient fluorescent "turning-on-enhanced" platform under near neutral conditions was established.


Assuntos
Estruturas Metalorgânicas , Nanocompostos , Colorimetria , Ferro , Oxirredutases , Ácidos Ftálicos
9.
Chemistry ; 27(35): 9141-9151, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33938042

RESUMO

Developing highly active and sensitive peroxidase mimics for L -cysteine (L -Cys) colorimetric detection is very important for biotechnology and medical diagnosis. Herein, polyoxometalate-doped porous Co3 O4 composite (NiMo6 @Co3 O4 ) was designed and prepared for the first time. Compared with pure and commercial Co3 O4 , NiMo6 @Co3 O4 (n) composites exhibit the enhanced peroxidase-mimicking activities and stabilities due to the strong synergistic effect between porous Co3 O4 and multi-electron NiMo6 clusters. Moreover, the peroxidase-mimicking activities of NiMo6 @Co3 O4 (n) composites are heavily dependent on the doping mass of NiMo6 , and the optimized NiMo6 @Co3 O4 (2) exhibits the superlative peroxidase-mimicking activity. More importantly, a sensitive L -Cys colorimetric detection is developed with the sensitivity of 0.023 µM-1 and the detection limit at least 0.018 µM in the linear range of 1-20 µM, which is by far the best enzyme-mimetic performances, to the best our knowledge.


Assuntos
Técnicas Biossensoriais , Colorimetria , Peroxidase , Peroxidases , Porosidade
10.
Inorg Chem ; 59(21): 15579-15582, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33054195

RESUMO

Four polyoxometalate (POM)-based Cu complexes with the hydroxylated pyridine analogue 3-(2-hydroxylpyrid-4-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl (btpo), H3{[Cu2(btpo)2](PW12O40)}·2H2O (1), H3{[Cu2(btpo)2](PMo12O40)}·2H2O (2), H2{[Cu2(btpo)2](SiW12O40)·SO4 (3), and H4{[Cu4(btpo)4](SiW12O40)}·8H2O (4), were synthesized hydrothermally under acid conditions. Single-crystal X-ray structural analysis reveals that 3-(pyrid-4-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl was hydroxylated into btpo in compounds 1-4, again providing structural evidence for the Gillard mechanism, in which H2O as a weak nucleophile can attack the α-C atom of N-heterocyclic molecules at a lower pH value (ca. 1.0) with the help of POMs.

11.
Talanta ; 220: 121373, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32928399

RESUMO

For the sake of effective colorimetric sensing-pattern, a sensitive colorimetric sensor was conceived based on polyoxometalates based metal-organic frameworks (POMOFs) and polydiallyldimethylammonium chloride functionalized reduced graphene oxide (PDDA-rGO) for the first time, in which PDDA as a "glue" molecule turns rGO nanosheets into general platforms for bonding POMOFs nanoparticles. Herein, a new POMOF compound with fascinating helices-on-helices feature, [Ni4(Trz)6(H2O)2][SiW12O40].4H2O (Trz = 1,2,4-triazole) (abbreviated as Ni4SiW12), was synthesized and characterized, then PDDA-rGO sheet as dispersive and conductive material was successfully introduced to Ni4SiW12 fabricating new PDDA-rGO/Ni4SiW12-n nanocomposites, (abbreviated as PMPG-n). The resulting PMPG-n nanocomposites as peroxidase mimetic show excellent catalytic activities under extreme condition (pH value 2.5), attributed to the nature and synergies from POMs, MOFs and PDDA-rGOs. Note that the peroxidase-like activity of PMPG-1 (the mass ratio of Ni4SiW12 to PDDA-rGO is 1:1) exhibits higher sensitivity (1-60 µM), faster response (10 min) and the lowest limit of detection (2.07 µM) among all reported materials to citric acid (CA) to date. This work opens up new application prospects in colorimetric sensing system for food quality control and safety, biotechnology and clinical diagnosis.


Assuntos
Colorimetria , Grafite , Nanocompostos , Técnicas Biossensoriais , Enzimas , Polieletrólitos
12.
Inorg Chem ; 59(13): 9244-9251, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32539363

RESUMO

A new 12-tungstovanadate-templated 3D nanocage framework, Ag10(µ4-ttz)4(H2O)4(VW12O40) (VW12@MOCF), was designed based on a "molecular library", hydrothermally synthesized, structurally characterized, and explored as anode material for lithium-ion batteries (LIBs). Combination of the structural superiority of VW12@MOCF with the good electrical conductivity of the single-walled carbon nanotubes (SWNTs) renders the VW12@MOCF/SWNT-2 nanocomposite reasonable electrochemical performance and stability as anode materials of LIBs. The successful cooperative fabrication of nanocages and polyoxometalate (POMs) must initiate extensive research interests.

13.
Analyst ; 145(11): 4021-4030, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32355933

RESUMO

To explore a novel colorimetric biosensor with high sensibility and selectivity, a new Wells-Dawson-type polyoxometalate (POM)-based metal-organic framework (MOF) with an eightfold helix, [Cu9(FKZ)12(H2O)8][H3P2W18O62]2·4H2O (CuFKZP2W18) (HFKZ = 1-(2,4-difluorophenyl)-1,1-bis[(1H-1,2,4-triazol-1-yl)methyl] ethanol), was successfully synthesized; then, polypyrrole (PPy) was introduced to fabricate CuFKZP2W18/PPy(n) nanocomposites (n = 7%, 15%, 30%) via a facile in situ oxidation polymerization process. All the results indicate that CuFKZP2W18/PPy(15%) as a colorimetric biosensor exhibits lower limits of detection (0.07 µM towards H2O2 and 0.627 µM towards ascorbic acid), smaller Km values (0.106 mM for H2O2 and 0.042 mM for o-phenylenediamine) and higher sensitivity (0.0227 1 µM-1 towards H2O2 and 0.0025 1 µM-1 to ascorbic acid) than most reported enzyme mimetics to the best of our knowledge.

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