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Layertronics, rooted in the layer Hall effect (LHE), is an emerging fundamental phenomenon in condensed matter physics and spintronics. So far, several theoretical and experimental proposals have been made to realize LHE, but all are based on antiferromagnetic systems. Here, using symmetry and tight-binding model analysis, we propose a general mechanism for engineering layertronics in a two-dimensional ferromagnetic multiferroic lattice. The physics is related to the band geometric properties and multiferroicity, which results in the coupling between Berry curvature and layer degree of freedom, thereby generating the LHE. Using first-principles calculations, we further demonstrate this mechanism in bilayer (BL) TcIrGe2S6. Due to the intrinsic inversion and time-reversal symmetry breakings, BL TcIrGe2S6 exhibits multiferroicity with large Berry curvatures at both the center and corners of the Brillouin zone. These Berry curvatures couple with the layer physics, forming the LHE in BL TcIrGe2S6. Our work opens a new direction for research on layertronics.
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An elevated level of blood uric acid (UA) can cause the formation of kidney stones, gout, and other diseases. We recently isolated a few DNA aptamers that can selectively bind to UA. In this work, we investigated the adsorption of a UA aptamer and random sequence DNA onto sodium urate crystals. Both DNA strands adsorbed similarly to urate crystals. In addition, both the UA aptamer and random DNA can inhibit the growth of urate crystals, suggesting a nonspecific adsorption mechanism rather than specific aptamer binding. In the presence of 500 nM DNA, the growth of needle-like sodium urate crystals was inhibited, and the crystals appeared granular after 6 h. To understand the mechanism of DNA adsorption, a few chemicals were added to desorb DNA. DNA bases contributed more to the adsorption than the phosphate backbone. Surfactants induced significant DNA desorption. Finally, DNA could also be adsorbed onto real UA kidney stones. This study provides essential insights into the interactions between DNA oligonucleotides and urate crystals, including the inhibition of growth and interface effects of DNA on sodium urate crystals.
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In order to explore novel natural product-based insecticidal agent, two important intermediates (2 and 3) and 4-acyloxy-2'-bromo-6'-chloropodophyllotoxin derivatives (4 a-f and 5 a-f) were designed and prepared, and their structures were confirmed by 1H-NMR, 13C NMR, HRMS, ESI-MS, optical rotation and melting point (mp). The stereochemical configuration of compound 4 b was unambiguously confirmed by single-crystal X-ray diffraction. Moreover, we evaluated the insecticidal activity of target compounds 4 a-f and 5 a-f against a serious agricultural pest of Mythimna separata by using the leaf-dipping method. Among all tested compounds, compounds 4 d, 5 d and 5 f exhibited stronger insecticidal activity with a final mortality rate exceeding 60 %. Especially compound 5 d exhibited the best insecticidal activity, with a final mortality rate of 74.1 %. It has been proven that introducing bromine or chlorine atoms at the C-2', C-2' and C-6' positions of the E ring of podophyllotoxin can produce more potent compounds. In addition, the configuration of the C-4 position is important for insecticidal activity, and 4ß-configuration is optimal. This will pave the way for further design, structural modification, and development of derivatives of podophyllotoxin as insecticidal agents.
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Inseticidas , Mariposas , Podofilotoxina , Inseticidas/síntese química , Inseticidas/farmacologia , Inseticidas/química , Animais , Podofilotoxina/farmacologia , Podofilotoxina/química , Podofilotoxina/síntese química , Podofilotoxina/análogos & derivados , Mariposas/efeitos dos fármacos , Relação Estrutura-Atividade , Estrutura Molecular , Cristalografia por Raios X , Conformação MolecularRESUMO
Twenty 3-acyloxymaltol/ethyl maltol derivatives (7a-j and 8a-j) were synthesized and evaluated in vitro for their anti-oomycete activity against Phytophthora capsici, respectively. Among all of twenty derivatives, more than half of the compounds 7f, 7h, 8a-h and 8j had anti-oomycete activity higher than the positive control zoxamide (EC50 = 22.23 mg/L), and the EC50 values of 18.66, 20.32, 12.80, 16.18, 10.59, 14.98, 16.80, 10.36, 15.32, 12.64, and 13.59 mg/L, respectively. Especially, compounds 8c and 8f exhibited the best anti-oomycete activity against P. capsici with EC50 values of 10.59 and 10.36 mg/L, respectively. Overall, hydroxyl group of maltol/ethyl maltol is important active modification site.
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The battery swelling originated from the electrode swelling is a big obstacle for the practical application of high-energy-density lithium-ion batteries (HED-LIBs). Herein, the HED-LIBs are constructed by SiOx /graphite composite anode and LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) cathode and their swelling behaviors are investigated at the cell, electrode, and particle scales. there are three expansion stages during the charging while one expansion followed by two contraction stages during the discharging process. The expansion ratio is in direct proportion to the ratio of SiOx content and about 10 times larger than that of the cathode. A 100 nm thick double-layer solid electrolyte interface, comprises LiF, Li2 O, and Li2 CO3 , forms on the surface of the SiOx particles, and evolves into a 300 nm thick triple-layer after cycling. The performance degradation of HED-LIBs is associated with the expansion of anodes, increase in resistance, and consumption of Li in the anodes during cycling. This study is expected to guide the future selection and design of HED-LIBs and battery packs.
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Uric acid is the end-product of purine metabolism in humans and an important biomarker for many diseases. To achieve the detection of uric acid without using enzymes, we previously selected a DNA aptamer for uric acid with a Kd of 1â µM but the aptamer required multiple Na+ ions for binding. Saturated binding was achieved with around 700â mM Na+ and the binding at the physiological condition was much weaker. In this work, a new selection was performed by alternating Mg2+ -containing buffers with Na+ and Li+ . After 13â rounds of selection, a new aptamer sequence named UA-Mg-1 was obtained. Isothermal titration calorimetry confirmed aptamer binding in both selection buffers, and the Kd was around 8â µM. The binding of UA-Mg-1 to UA required only Mg2+ . This is an indicator of successful switching of metal dependency via the salt-toggled selection method. The UA-Mg-1 aptamer was engineered into a fluorescent biosensor based on the strand-displacement assay with a limit of detection of 0.5â µM uric acid in the selection buffer. Finally, comparison with the previously reported Na+ -dependent aptamer and a xanthine/uric acid riboswitch was also made.
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Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Humanos , Ácido Úrico , Técnica de Seleção de Aptâmeros/métodos , Aptâmeros de Nucleotídeos/química , Cloreto de Sódio , Técnicas Biossensoriais/métodosRESUMO
In this paper, we investigate the efficiency droop phenomenon in green and blue GaN-based micro-LEDs of various sizes. We discuss the distinct carrier overflow performance in green and blue devices by examining the doping profile extracted from capacitance-voltage characterization. By combining the size-dependent external quantum efficiency with the ABC model, we demonstrate the injection current efficiency droop. Furthermore, we observe that the efficiency droop is induced by injection current efficiency droop, with green micro-LEDs exhibiting a more pronounced droop due to more severe carrier overflow compared to blue micro-LEDs.
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Microplastics have attracted considerable attention because of concerns regarding their environmental risks to living systems. The interaction between the lipid bilayer and microplastics is important for examining the potential harm to biological membranes in the presence of microplastics. In addition, membrane coatings may change the surface and colloidal properties of microplastics. Herein, phosphatidylcholine (PC) lipids, whose headgroup is most common in cell membranes, were used as model lipids. The adsorption and rupture of PC liposomes on microplastics were systematically studied. We found that divalent metal ions, such as Mg2+ and Ca2+, facilitate liposome adsorption onto microplastics and induce 40-55% liposome leakage at 2.5 mM. In contrast, to achieve a similar effect, 300 mM Na+ was required. Adsorption and rupture followed the same metal concentration requirements, suggesting that liposome adsorption was the rate-limiting step. After adsorption with liposomes, microplastics became more hydrophilic and were better dispersed in water. A similar behavior was observed for all five types of tested microplastics, including PP, PE, PVC, PET, and PS. Leakage also occurred in ocean water. This study provides fundamental insights into the interactions between liposomes and microplastics and has implications for the colloidal and transport properties of microplastics.
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Microplásticos , Poluentes Químicos da Água , Lipossomos/metabolismo , Plásticos , Adsorção , Bicamadas Lipídicas , Cloreto de Sódio , Água , Poluentes Químicos da Água/análiseRESUMO
Microbes contribute to the organic matter decomposition (OMD) in river ecosystems. This study considers two aspects of OMD in river ecosystems which have not been examined in scientific studies previously, and these are the microbial interactions in OMD and the influence of environmental factors on microbial interactions. Cotton strip (CS), as a substitute for organic matter, was introduced to Luanhe River Basin in China. The results of CS assay, microbial sequencing, and redundancy analysis (RDA) showed that CS selectively enriched bacterial and fungal groups related to cellulose decomposition, achieving cotton strip decomposition (CSD). Bacterial phylum Proteobacteria and fungal phyla Rozellomycota and Ascomycota were the dominant groups associated with CSD. Network analysis and Mantel test results indicated that bacteria and fungi on CS cooperatively formed an interaction network to achieve the CSD. In the network, modules 2 and 4 were significantly positively associated with CSD, which were considered as the key modules in this study. The key modules were mainly composed of phyla Proteobacteria and Ascomycota, indicating that microbes in key modules were the effective decomposers of CS. Although keystone taxa were not directly associated with CSD, they may regulate the genera in key modules to achieve the CSD, since some keystone taxa were linked with the microbial genera associated with CSD in the key modules. Total nitrogen (TN) and temperature in water were the dominant environmental factors positively influenced CSD. The key modules 2 and 4 were positively influenced by water temperature and TN in water, respectively, and two keystone taxa were positively associated with TN. This profoundly revealed that water temperature and TN influenced the OMD through acting on the keystone taxa and key modules in microbial interactions. The research findings help us to understand the microbial interactions influenced by environmental factors in OMD in river ecosystems.
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Ecossistema , Rios , Rios/microbiologia , Nitrogênio , Temperatura , Bactérias/genética , Interações Microbianas , ÁguaRESUMO
Pests cause substantial damage to human environments; therefore, studying insecticidal mechanisms is crucial for improving pest control. However, the use of chemical pesticides can cause irreversible secondary damage. In this study, we used network pharmacology to investigate the effect of Sophora flavescens Alt., as a biological pest control agent, on glucose-6-phosphate 1-dehydrogenase, thymidylate synthase, and a translocation protein in aphids. The stability and reliability of target proteins was analyzed using molecular docking and molecular dynamic simulations. Enzyme activity assays validated the feasibility of network pharmacology to obtain actionable targets. We used interdisciplinary integration to study pest control and network pharmacology to identify how Sophora flavescens Alt. resists aphid attacks. The results show that the use of network pharmacology can increase the accuracy and specificity of our predictions for the molecules targeted by insecticides. This approach will facilitate improved, environmentally friendly pest control development in the future.
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Afídeos , Sophora , Animais , Humanos , Sophora flavescens , Simulação de Acoplamento Molecular , Farmacologia em Rede , Reprodutibilidade dos Testes , Sophora/químicaRESUMO
Particulate matter damages engines of vehicles when blown into the ventilation system. Conventional engine-intake filter is cellulose microfiber board with an average diameter larger than ten microns, which has low removal efficiency of ultrafine particular matter. In this work, we apply ultrafine polyurethane nanofibers (â¼122.8 nm) onto pleated cellulose board using scalable multinozzle electroblow spinning technology, which improves filtration efficiency of particulate matter with a diameter of less than 0.3 µm PM0.3 greatly. The thermoplastic polyurethane 85A nanofiber membranes are transparent, and display superior filtration performance which meets up with the 95% filtration efficiency standard in GB 19083-2010 technical requirements for protective face mask for medical use. The lightweight pleated thermoplastic polyurethane/cellulose composites intercept â¼90% ultrafine PM0.3 under airflow velocity of 32 L min-1 and possess great resistance to shock. These hierarchically designed filters follow a mechanical mechanism and can be used in on-road and off-road cars in the long run.
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Filtros de Ar , Celulose , Filtração , Material Particulado , PoliuretanosRESUMO
Lithium-air batteries (LABs) have attracted extensive attention due to their ultra-high energy density. At present, most LABs are operated in pure oxygen (O2) since carbon dioxide (CO2) under ambient air will participate in the battery reaction and generate an irreversible by-product of lithium carbonate (Li2CO3), which will seriously affect the performance of the battery. Here, to solve this problem, we propose to prepare a CO2 capture membrane (CCM) by loading activated carbon encapsulated with lithium hydroxide (LiOH@AC) onto activated carbon fiber felt (ACFF). The effect of the LiOH@AC loading amount on ACFF has been carefully investigated, and CCM has an ultra-high CO2 adsorption performance (137 cm3 g-1) and excellent O2 transmission performance by loading 80 wt% LiOH@AC onto ACFF. The optimized CCM is further applied as a paster on the outside of the LAB. As a result, the specific capacity performance of LAB displays a sharp increase from 27,948 to 36,252 mAh g-1, and the cycle time is extended from 220 h to 310 h operating in a 4% CO2 concentration environment. The concept of carbon capture paster opens a simple and direct way for LABs operating in the atmosphere.
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Stroke is a disastrous neurological disease with high morbidity and mortality. The mechanism of the pathological process is extremely complicated and unclear. Although many basic studies have confirmed molecular mechanism of brain injury after stroke, these studies have not yet translated into treatment and clinical application. Ferroptosis is a form of cell death that is distinct from necrosis, apoptosis, and autophagy morphologically and biochemically and is characterized by iron-dependent accumulation of lipid peroxides. Despite ferroptosis being first identified in cancer cells, it was recently revealed to also be a significant factor in the pathological process of stroke. A better understanding of ferroptosis in stroke may provide us with better therapeutic targets to treat this devastating disease. Here, we systematically summarized the current mechanism of ferroptosis and reviewed the current studies regarding the relationship between ferroptosis and stroke.
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Ferroptose/fisiologia , Acidente Vascular Cerebral/patologia , Animais , HumanosRESUMO
Protein disulfide isomerase A4 (PDIA4) is highly expressed in clear cell ovarian carcinoma and lung cancer. Through analysis of TCGA database and CGGA database, we noted that PDIA4 is a key promotor of glioblastoma (GBM). However, the detailed role and molecular mechanism of PDIA4 in GBM remain unclear. In this study, the expression pattern and biological role of PDIA4 in GBM was investigated. PDIA4 was overexpressed in GBM tumor samples and cell lines and positively correlated with pathological grades in glioma patients. In addition, downregulation of PDIA4 promoted apoptosis and inhibited proliferation of GBM. Meanwhile, there was a concurrent decrease in aerobic glycolysis metabolites. Mechanistically, PDIA4 downregulation promoted the apoptosis of GBM cells by increased the expression of apoptosis pathway proteins (caspase 3, caspase 9 and Bax). Downregulation of PDIA4 decreased energy demand and inhibited GBM growth in vitro and in vivo. Besides, such effect also inhibited the PI3K/AKT/m-TOR pathway by inhibiting protein phosphorylation levels of PI3K, AKT and m-TOR. After addition of PI3K/AKT/mTOR pathway activator 740Y-P, the effect of PDIA4 knockdown on GBM was reversed. Therefore, we believe that PDIA4 regulates the proliferation via activating the PI3K/AKT/m-TOR pathway and suppression of apoptosis in glioblastoma. It could be used as a potential target for the treatment of GBM.
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The aim of this study is to characterize the molecular properties of multilineage differentiating stress-enduring (Muse) cells compared with dermal fibroblasts (FBs) and to characterize differences in their transcriptomes and open chromatin regions that are involved in cellular plasticity. Assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) and RNA sequencing (RNA-seq) analyses was then performed on FBs and Muse cells. Subsequently, cell type-selective gene regulatory regions were identified by coalition analysis. Expression patterns of transcription factors (TFs) and signaling pathways intermediates were verified using quantitative real-time polymerase chain reaction and Western blot analyses. RNA-seq identified 2355 significantly differentially expressed genes (DEGs) that regulate the transcriptome, including 1222 upregulated and 1133 downregulated DEGs. The general panorama of RNA-seq and ATAC-seq analyses confirmed the differences in TFs and open chromatin regions between FBs and Muse cells. ATAC-seq analysis showed that Muse cells had more reproducible and meaningful peaks than FBs, and the peak signals were concentrated near promoter-transcription start site areas. In genomic regions that can be preferentially accessed in FBs and Muse cells, more than 200 TFs had binding motif sequences. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and coalition analyses identified differences in factors involved in the cell cycle and the protein kinase B (AKT) signaling pathway of FBs and Muse cells. The results of RNA-seq and ATAC-seq analyses clarified the genetic basis of the different biological properties of Muse cells and FBs. These results suggest that the cell cycle transition and the AKT signaling pathway may affect the morphology and biological characteristics of Muse cells.
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Sequenciamento de Cromatina por Imunoprecipitação , Proteínas Proto-Oncogênicas c-akt , Alprostadil/metabolismo , Cromatina/metabolismo , Fibroblastos/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA-Seq , Análise de Sequência de RNARESUMO
Subarachnoid hemorrhage (SAH) is a worldwide devastating type of stroke with high mortality and morbidity. Accumulating evidence show early brain injury (EBI) as the leading cause of mortality after SAH. The pathological processes involved in EBI include decreased cerebral blood flow, increased intracranial pressure, vasospasm, and disruption of the blood-brain barrier. In addition, neuroinflammation, oxidative stress, apoptosis, and autophagy have also been proposed to contribute to EBI. Among the various processes involved in EBI, neuronal apoptosis has been proven to be a key factor contributing to the poor prognosis of SAH patients. Meanwhile, as another important catabolic process maintaining the cellular and tissue homeostasis, autophagy has been shown to be neuroprotective after SAH. Studies have shown that enhancing autophagy reduced apoptosis, whereas inhibiting autophagy aggravate neuronal apoptosis after SAH. The physiological substrates and mechanisms of neuronal autophagy and apoptosis by which defects in neuronal function are largely unknown. In this review, we summarize and discuss the role of autophagy and apoptosis after SAH and contribute to further study for investigation of the means to control the balance between them.
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Lesões Encefálicas , Hemorragia Subaracnóidea , Animais , Ratos , Humanos , Hemorragia Subaracnóidea/metabolismo , Hemorragia Subaracnóidea/patologia , Encéfalo/metabolismo , Ratos Sprague-Dawley , Autofagia , Apoptose/fisiologiaRESUMO
In order to explore novel natural product-based anti-oomycete and nematicidal agents, sixteen unreported 2-sulfonyloxyhinokitiol derivatives were prepared using the principle of active splicing, and structurally confirmed by proton nuclear magnetic resonance (1 H-NMR), carbon-13 nuclear magnetic resonance (13 C-NMR), high-resolution mass spectrometry (HRMS), and melting point. Moreover, we evaluated the title compounds as anti-oomycete and nematicidal agents against two serious agricultural pests of Phytophthora capsici and Meloidogyne incongnita. Among the sixteen hinokitiol esters tested: (1) Compounds 3a and 3m exhibited the most potent anti-oomycete activity compared to zoxamide against P. capsici, and the median effective concentration (EC50 ) values of 3a, 3m, and zoxamide were 18.64, 21.11, and 23.15â mg/L, respectively; Further studies showed that the existence of seven membered ring and carbonyl group was the necessary condition for the high anti-oomycete activity of hinokitiol. (2) Compounds 3n and 3p exhibited more promising nematicidal activity than hinokitiol, and the median lethal concentration (LC50 ) values of 3n, 3p and 1 against M. incongnita were 0.2111, 0.2079, and 0.3933â mg/L, respectively. This result will pave the way for further modification of hinokitiol to develop potential new fungicides and nematicides.
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Produtos Biológicos , Fungicidas Industriais , Phytophthora , Amidas , Antinematódeos/química , Antinematódeos/farmacologia , Monoterpenos , Prótons , Tropolona/análogos & derivadosRESUMO
In order to discover highly active fungicides, sixteen novel sulfonate derivatives of Fenjuntong were synthesized by structural modification of 2'-hydroxybutyrophenone, and their anti-oomycete activity against Phytophthora capsici Leonian was determined in this study. Among all tested compounds, compound 3b displayed more significant anti-oomycete activity than the precursor Fenjuntong against P.â capsici, and the EC50 values of 3b and Fenjuntong were 84.50 and 517.25â mg/L, respectively. By comparing the anti-oomycete activity of compounds 3a-p, I-a-p, and II-a-p, the following conclusions were drawn: (1)â Hydroxy group is well tolerated, and sulfonylation of hydroxy group enhances its anti-oomycete activity. (2)â The proper length of the ketone carbonyl chain is very important for their anti-oomycete activity. (3)â The presence of a site methoxy group in the structural skeleton is closely related to the anti-oomycete activity. These important results will pave the way for further modification of Fenjuntong to develop potential new fungicides.
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Fungicidas Industriais , Phytophthora , Fungicidas Industriais/química , Doenças das PlantasRESUMO
To discover novel molecules with unique mechanism against plant pathogenic oomycetes, sixteen new sulfonate derivatives of ethyl maltol (3a-p) were synthesized by structural modification of 2-ethyl-3-hydroxy-4H-pyran-4-one, and their anti-oomycete activity against a serious agricultural disease, Phytophthora capsici Leonian was determined in this study. Among all tested compounds, derivatives 3e, 3m and 3p exhibited the most potent anti-oomycete activity against P.â capsici with EC50 values of 19.40, 21.04 and 31.10â mg/L, respectively; especially 3e and 3m showed the best promising and pronounced anti-oomycete activity than zoxamide (EC50 =26.87â mg/L). The results further proved that 4-tert-butylphenylsulfonyl group, 3-nitro-4-chlorophenylsulfonyl group and 8-quinolinesulfonyl group introduced at the hydroxy position of ethyl maltol or maltol were necessary for obtaining the most potent compounds. Further mechanism studies of P.â capsici treated with 3e demonstrated that this compound can affect the growth of mycelia by disrupting the integrity of the membrane, and the higher the concentration of the compound is, the greater the degree of membrane integrity damage. These important results will pave the way for further modification of ethyl maltol to develop potential new fungicides.
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Fungicidas Industriais , Phytophthora , Fungicidas Industriais/farmacologia , Doenças das Plantas , Plantas , PironasRESUMO
BACKGROUND: Stimulator of interferon genes (STING) activation favors effective innate immune responses against viral infections. Its role in chronic rhinosinusitis with nasal polyps (CRSwNP) remains unknown. OBJECTIVE: Our aim was to explore the expression, regulation, and function of STING in CRSwNP. METHODS: STING expression in sinonasal mucosal samples was analyzed by means of quantitative RT-PCR, immunohistochemistry, flow cytometry, and Western blotting. Regulation and function of STING expression were explored by using cultured primary human nasal epithelial cells (HNECs) and cells of the line BEAS-2B in vitro. RESULTS: STING expression was reduced in eosinophilic nasal polyps compared with that in noneosinophilic nasal polyps and control tissues. STING was predominantly expressed by epithelial cells in nasal tissue and was downregulated by IL-4 and IL-13 in a signal transducer and activator of transcription 6 (STAT6)-dependent manner. HNECs derived from eosinophilic polyps displayed compromised STING-dependent type I interferon production but heightened IL-13-induced STAT6 activation and CCL26 production as compared with HNECs from noneosinophilic polyps and control tissues, which were rescued by exogenous STING overexpression. Knocking down or overexpressing STING decreased or enhanced expression of suppressor of cytokine signaling 1 (SOCS1) in BEAS-2B cells, respectively, independent of the canonic STING pathway elements TBK1 and IRF3. Knocking down SOCS1 abolished the inhibitory effect of STING on IL-13 signaling in BEAS-2B cells. STING expression was positively correlated with SOCS1 expression but negatively correlated with CCL26 expression in nasal epithelial cells from patients with CRSwNP. CONCLUSIONS: Reduced STING expression caused by the type 2 milieu not only impairs STING-dependent type I interferon production but also amplifies IL-13 signaling by decreasing SOCS1 expression in nasal epithelial cells in eosinophilic CRSwNP.