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Hierarchically structural particles (HSPs) are highly regarded as favorable nanomaterials for superhydrophobic coating due to their special multiscale structure and surface physicochemical properties. However, most of the superhydrophobic coatings constructed from HSPs are monofunctional, constraining their broader applications. Moreover, traditional methods for constructing HSPs mostly rely on complicated chemical routes and template removal. Herein, we propose an innovative strategy (one-pot method) for producing multifunctional hierarchical hybrid particles (HHPs). Polysilsesquioxane (PSQ), generated from hydrolysis condensation of methyltriethoxylsilane, is used as the sole stabilizer to anchor on the surface of styrene and short fluoroalkyl compound tridecafluorooctyl acrylate comonomers droplets, forming a mesoporous PSQ shell. Subsequently, the comonomers inside of the shell perform restricted polymerization to generate the HHP due to the driving of the mesoporous capillary force. The HHP is then mixed with waterborne polyurethane (WPU) to develop a robust nanocomposite coating (WPU-HHP). Through the deliberate design of the HHP components, the WPU-HHP coating has thermal insulation, photoluminescence properties, and the ability to achieve a wettability transition during abrasion. Our research has achieved the integration of multifunctionality in one waterborne hybrid system, broadening the application areas of nanocomposite coatings.
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Domestication of tomato (Solanum lycopersicum) has led to large variation in fruit size and morphology. The development of the distal end of the fruit is a critical factor in determining its overall shape. However, the intricate mechanisms underlying distal fruit development require further exploration. This study aimed to investigate the regulatory role of an organelle RNA recognition motif (RRM)-containing protein SlORRM2 in tomato fruit morphology development. Mutant plants lacking SlORRM2 exhibited fruits with pointed tips at the distal end. However, this phenotype could be successfully restored through the implementation of a "functional complementation" strategy. Our findings suggest that the formation of pointed tips in the fruits of the CR-slorrm2 mutants is linked to alterations in the development of the ovary and style. We observed a substantial decrease in the levels of indole-3-acetic acid (IAA) and altered expression of IAA-related response genes in the ovary and style tissues of CR-slorrm2. Moreover, our data demonstrated that SlORRM2 plays a role in regulating mitochondrial RNA editing sites, particularly within genes encoding various respiratory chain subunits. Additionally, the CR-slorrm2 mutants exhibited modified organellar morphology and increased levels of reactive oxygen species. These findings provide valuable insights into the mechanisms underlying the formation of fruit pointed tips in tomato and offer genetic resources for tomato breeding.
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Frutas , Proteínas de Plantas , Edição de RNA , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Edição de RNA/genética , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Mutação/genética , Espécies Reativas de Oxigênio/metabolismo , FenótipoRESUMO
The discovery of non-precious catalysts for replacing the precious metal of ruthenium in the oxygen evolution reaction (OER) represents a key step in reducing the cost of green hydrogen production. The 2D d-MHOFs, a new 2D materials with controllable oxygen vacancies formed by controlling the degree of coordination bridging between metal hydroxyl oxide and BDC ligands are synthesized at room temperature, exhibit excellent OER properties with low overpotentials of 207 mV at 10 mA cm-2. High-resolution transmission electron microscopy images and density functional theory calculations demonstrate that the introduction of oxygen vacancy sites leads to a lattice distortion and charge redistribution in the catalysts, enhancing the OER activity of 2D d-MHOFs comprehensively. Synchrotron radiation and in situ Raman/Fourier transform infrared spectroscopy indicate that part of oxygen defect sites on the surface of 2D d-MHOFs are prone to transition to highly active metal hydroxyl oxides during the OER process. This work provides a mild strategy for scalable preparation of 2D d-MHOFs nanosheets with controllable oxygen defects, reveals the relationship between oxygen vacancies and OER performance, and offers a profound insight into the basic process of structural transformation in the OER process.
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Vitamin C-based cluster therapy, which involves the combined application of hydrocortisone, vitamin C, and thiamine (HAT), is a recently proposed new treatment option for sepsis on top of conventional treatment. This therapy has a strong theoretical basis, but its clinical efficacy remains inconclusive. This review summarizes the rationale for HAT therapy for sepsis and describes the evaluation of its efficacy in clinical observational studies and randomized controlled trials, with the aim of providing a reference for the future clinical practice application of HAT therapy in sepsis.
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As the important signaling molecules in plants, peptides at femtomolar levels are recognized and bound by the corresponding plasma membrane-localized receptor-like kinases. This triggers the peptide-receptor-mediated intercellular signal transduction for regulation of the stem cell growth and proliferation, modulation of the development of plant organs (such as roots, stems, leaves, flowers, and fruits) as well as coordinating plant responses to biotic and abiotic stresses. With the advancement of in-depth research, an increasing number of studies have revealed the crucial role of peptides in regulating agronomic traits of various crops, including rice (Oryza sativa), maize (Zea mays), potato (Solanum tuberosum) and tomato (Solanum lycopersicum). These findings suggest the great potentials of utilizing the peptide signaling for genetic improvement of crops. In this review, we provide a comprehensive overview of the biological function and molecular mechanism of peptide-receptor signaling in plants, and highlight the advances in research of peptides in regulating crop yield, quality and resistance. Then, we discuss the strategies for the application of peptide signaling in crop improvement. Finally, we point out some future directions for peptide research in plant.
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Oryza , Transdução de Sinais , Produtos Agrícolas/genética , Agricultura , Ciclo Celular , PeptídeosRESUMO
BACKGROUND: Exposure to air pollutants may cause immune responses and further allergic diseases, but existing studies have mostly, if not all, focused on effects of short-term exposure to PM2.5 on allergic diseases. OBJECTIVES: We estimated associations of long-term exposure to PM2.5 chemical constituents with allergic disease risks and effect modification. METHODS: We used the baseline of a newly established, provincially representative cohort of 51,480 participants in southwest China. The presence of allergic rhinitis, allergic asthma, urticaria, and allergic conjunctivitis was self-reported by following a formed questionnaire in face-to-face interviews. The average concentrations of PM2.5 chemical constituents (NO3-, SO42-, NH4+, organic matter [OM], and black carbon [BC]) over participants' residence were estimated using machine learning models. Logistic regression with double robust estimator and weighted quantile sum regression were used to estimate the effects of PM2.5 chemical constituents on allergic disease risks, as well as relative importance of each PM2.5 chemical constituent. RESULTS: Per interquartile range increase in the concentration of all PM2.5 chemical constituents was associated with the elevated risks for allergic asthma (OR = 1.79 [1.41-2.26]), allergic conjunctivitis (1.54 [1.19-2.00]), urticaria (1.36 [1.25-1.48]), and allergic rhinitis (1.18 [1.11-1.26]). NO3- contributed more to risks for allergic asthma (weight = 46.05 %), urticaria (72.29 %), and allergic conjunctivitis (47.65 %), while NH4+ contributed more to allergic rhinitis (78.07 %). OM contributed most to the risks for allergic asthma (30.81 %) and allergic conjunctivitis (31.40 %). BC was also associated with allergic rhinitis, urticaria, and allergic conjunctivitis, only with a considerable weight for urticaria (24.59 %). Joint effects of PM2.5 chemical constituents on risks for allergic rhinitis and urticaria were stronger in minorities and farmers than their counterparts. CONCLUSION: Long-term exposure to PM2.5 chemical constituents was associated with the increased allergic disease risks, with NO3- and NH4+ accounting for the largest variance of the associations. Our findings would serve as scientific evidence for developing more explicit strategies of air pollution control.
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Poluentes Atmosféricos , Poluição do Ar , Asma , Conjuntivite Alérgica , Rinite Alérgica , Urticária , Humanos , Poluição do Ar/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Estudos de Coortes , Conjuntivite Alérgica/epidemiologia , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Asma/induzido quimicamente , Asma/epidemiologia , Rinite Alérgica/induzido quimicamente , Rinite Alérgica/epidemiologia , China/epidemiologia , Exposição AmbientalRESUMO
For high capacitance multilayer ceramic capacitors, high dielectric constant and lead-free ceramic nanoparticles are highly desired. However, as the particle size decreases to a few tens of nanometers, their dielectric constant significantly decreases, and the underlying mechanism has yet to be fully elucidated. Herein, we report a systematic investigation into the crystal structure-dielectric property relationship of combustion-made BaTiO3 (BTO) nanocrystals. When the nanocrystal size was 100 nm and below, a metastable paraelectric cubic phase was found in the as-received BTO (denoted as arBTO) nanocrystals based on an X-ray diffraction (XRD) study. A stable ferroelectric tetragonal phase was present when the nanocrystal size was above 200 nm. Notably, the cubic arBTO (particle size ≤100 nm) exhibited tetragonal fluctuations as revealed by Raman spectroscopy, whereas the tetragonal arBTO (particle size ≥200 nm) contained â¼10% cubic fraction according to the Rietveld fitting of the XRD profiles. Thermal annealing of the multi-grain tetragonal arBTO at 950 °C yielded single crystals of annealed BTO (denoted as anBTO), whose dielectric constants were higher than those of arBTO. However, the single crystalline anBTO prevented the formation of 90° domains; therefore, they exhibited a low dielectric constant of â¼300. Although X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy could not identify the exact structural defects, our study revealed that surface and bulk defects formed during synthesis affect the final crystal structures and thus the dielectric properties of BTO nanocrystals with different sizes. The understanding obtained from this study will help us design high dielectric constant perovskite nanocrystals for next-generation multilayer ceramic capacitor applications.
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Objective: Aromatherapy has been used for patients on maintenance hemodialysis (MHD), but the outcomes are still controversial. Thus, we conducted this study to systematically evaluate the effect of aromatherapy on the quality of life of patients on MHD.Methods: We searched the PubMed, Embays, Scopus, Web of Science, and CNKI databases for randomized controlled trials that evaluated the use of aromatherapy in dialysis patients and reported at least one outcome of interest.Results: Twenty-two relevant studies were included in the meta-analysis. The meta-analysis revealed that aromatherapy significantly increased subjective sleep quality (a lower score indicates better sleep quality) [standardized mean difference (SMD) = -1.52, 95% CI (-2.38, -0.67), p < 0.01] and reduced fatigue [SMD = -1.14, 95% CI (-1.95, -0.33), p = 0.01], anxiety [SMD = -1.38, 95% CI (-2.09, -0.67), p < 0.01], symptoms of restless legs syndrome [RLS; SMD = -1.71, 95% CI (-2.09, -1.33), p < 0.01], and arteriovenous fistula puncture pain [SMD= -1.56, 95% CI (-2.60, -0.52), p < 0.01].Conclusions: Aromatherapy may be used as a novel complementary and alternative therapy to improve sleep quality and reduce fatigue, anxiety, symptoms of RLS, and arteriovenous fistula puncture pain in patients on MHD.
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Aromaterapia , Humanos , Qualidade de Vida , Dor , Diálise Renal , FadigaRESUMO
Emerging solar interfacial evaporation offers the most promising response to the severe freshwater crisis. However, the most challenging bottleneck is the conflict between resisting salt accumulation and maintaining high evaporation performance since conventional salt-resistant evaporators enhance water flow to remove salt, leading to tremendous heat loss. Herein, an ion-transfer engineering is proposed via a Janus ion-selective hydrogel that enables ion-electromigration salt removal, breaking the historical dependence on water convection, and significantly lowering the heat loss. The hydrogels drive cations downward and anions upward, away from the evaporation surfaces. An electrical potential is thus established inside the evaporator and salt in 15 wt% brine is removed stably for seven days. A record-high evaporation rate of 6.86 kg m-2 h-1 in 15 wt% brine, 2.5 times the previously reported works, is achieved. With the from-scratch salt-resistant route, comprehensive water-thermal analysis, and record-high performance, this work holds great potential for the future salt-resistant evaporators.
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PURPOSE: Many studies have shown that cytochrome P450 (CYP) gene polymorphisms are usually associated with an increased risk of cardiovascular and cerebrovascular diseases. To explore the association of CYP2C8 and CYP2J2 gene polymorphisms with hypertensive intracerebral hemorrhage (HICH) in the Han Chinese population. METHODS: Forty HICH patients and 40 control subjects were recruited for this study. Two single nucleotide polymorphisms (SNP) (rs1058932, rs2275622) in the CYP2C8 gene and two SNPs (rs2271800, rs1155002) in the CYP2J2 gene were selected for genotyping by direct sequencing. Statistical analysis was applied to examine the effect of genetic variation on HICH. RESULTS: We found that variant alleles of CYP2C8 rs1058932 (A) and rs2275622 (C) were both significantly associated with HICH, especially in females. We also found significant associations of CYP2C8 rs1058932 (A) and rs2275622 (C) variant alleles with poor outcomes in HICH patients, especially in males. CONCLUSIONS: CYP2C8 gene polymorphisms might increase the risk of HICH in the Han Chinese population and might lead to poor outcomes. This finding adds to the body of literature supporting novel therapeutic strategies for HICH.
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Citocromo P-450 CYP2J2 , Hemorragia Intracraniana Hipertensiva , Masculino , Feminino , Humanos , Citocromo P-450 CYP2C8/genética , Sistema Enzimático do Citocromo P-450/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Plants and microbial pathogens often engage in a fierce war that determines their survival. Host plants have evolved sophisticated regulatory mechanisms to fine-tune defense responses to counter attacks from pathogens, while pathogens often hijack the lipid-derived phytohormone jasmonate to cause hormonal signaling imbalances for efficient infection. This review focuses on the jasmonate-based warfare between host plants and pathogenic intruders, and further discusses approaches to uncouple plant growth and defense tradeoffs in crop breeding.
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Melhoramento Vegetal , Doenças das Plantas , Plantas , Reguladores de Crescimento de Plantas , Ciclopentanos , OxilipinasRESUMO
RNA editing in plant organelles involves numerous C-U conversions, which often restore evolutionarily conserved codons and may generate new translation initiation and termination codons. These RNA maturation events rely on a subset of nuclear-encoded protein cofactors. Here, we provide evidence of the role of SlRIP1b on RNA editing of mitochondrial transcripts in tomato (Solanum lycopersicum) plants. SlRIP1b is a RIP/MORF protein that was originally identified as an interacting partner of the organellar editing factor SlORRM4. Mutants of SlRIP1b, obtained by CRISPR/Cas9 strategy, exhibited abnormal carpel development and grew into fruit with more locules. RNA-sequencing revealed that SlRIP1b affects the C-U editing of numerous mitochondrial pre-RNA transcripts and in particular altered RNA editing of various cytochrome c maturation (CCM)-related genes. The slrip1b mutants display increased H2 O2 and aberrant mitochondrial morphologies, which are associated with defects in cytochrome c biosynthesis and assembly of respiratory complex III. Taken together, our results indicate that SlRIP1b is a global editing factor that plays a key role in CCM and oxidative phosphorylation system biogenesis during fruit development in tomato plants. These data provide important insights into the molecular roles of organellar RNA editing factors during fruit development.
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Solanum lycopersicum , Solanum lycopersicum/genética , Edição de RNA/genética , Frutas/genética , Citocromos c/genética , Organelas/genética , Plantas/genética , RNA , RNA MitocondrialRESUMO
Tomato ripening is a complex and dynamic process coordinated by many regulatory elements, including plant hormones, transcription factors, and numerous ripening-related RNAs and proteins. Although recent studies have shown that some RNA-binding proteins are involved in the regulation of the ripening process, understanding of how RNA-binding proteins affect fruit ripening is still limited. Here, we report the analysis of a glycine-rich RNA-binding protein, RZ1A-Like (RZ1AL), which plays an important role in tomato ripening, especially fruit coloring. To analyze the functions of RZ1AL in fruit development and ripening, we generated knockout cr-rz1al mutant lines via the CRISPR/Cas9 gene-editing system. Knockout of RZ1AL reduced fruit lycopene content and weight in the cr-rz1al mutant plants. RZ1AL encodes a nucleus-localized protein that is associated with Cajal-related bodies. RNA-seq data demonstrated that the expression levels of genes that encode several key enzymes associated with carotenoid biosynthesis and metabolism were notably downregulated in cr-rz1al fruits. Proteomic analysis revealed that the levels of various ribosomal subunit proteins were reduced. This could affect the translation of ripening-related proteins such as ZDS. Collectively, our findings demonstrate that RZ1AL may participate in the regulation of carotenoid biosynthesis and metabolism and affect tomato development and fruit ripening.
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Black phosphorus/two-dimensional (2D) metal-organic framework (BP@MOF) heterojunctions were synthesized via templated growth of 2D MOF-Fe/Co nanoplatelets on the surface of exfoliated BP nanosheets at room temperature. Because Fe3+ and Co2+ ions were absorbed onto the BP surface through coordination with the lone pair electrons of 2D BP, the BP@MOF heterojunction had an intimate interface with strong interactions. Electrochemical oxygen and hydrogen evolution reactions were studied using BP@MOF as the electrocatalyst. High activity of the overall water splitting in 1.0 M KOH was observed under a current density of 10 mA cm-2. The corresponding overpotentials for HER and OER were as low as 180 and 246 mV, respectively. Meanwhile, the BP@MOF exhibited good environmental stability and long-term electrocatalytic activity for OER and HER, owing to the encapsulation of BP nanosheets by the 2D MOF-Fe/Co. Through this study, a unique hybrid 2D nanomaterial is discovered for the efficient electrolytic splitting of water.
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Many glycine-rich RNA-binding proteins (GR-RBPs) have critical functions in RNA processing and metabolism. Here, we describe a role for the tomato (Solanum lycopersicum) GR-RBP SlRBP1 in regulating mRNA translation. We found that SlRBP1 knockdown mutants (slrbp1) displayed reduced accumulation of total chlorophyll and impaired chloroplast ultrastructure. These phenotypes were accompanied by deregulation of the levels of numerous key transcripts associated with chloroplast functions in slrbp1. Furthermore, native RNA immunoprecipitation-sequencing (nRIP-seq) recovered 61 SlRBP1-associated RNAs, most of which are involved in photosynthesis. SlRBP1 binding to selected target RNAs was validated by nRIP-qPCR. Intriguingly, the accumulation of proteins encoded by SlRBP1-bound transcripts, but not the mRNAs themselves, was reduced in slrbp1 mutants. Polysome profiling followed by RT-qPCR assays indicated that the polysome occupancy of target RNAs was lower in slrbp1 plants than in wild-type. Furthermore, SlRBP1 interacted with the eukaryotic translation initiation factor SleIF4A2. Silencing of SlRBP1 significantly reduced SleIF4A2 binding to SlRBP1-target RNAs. Taking these observations together, we propose that SlRBP1 binds to and channels RNAs onto the SleIF4A2 translation initiation complex and promotes the translation of its target RNAs to regulate chloroplast functions.
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Solanum lycopersicum , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/genética , Fotossíntese/genética , Polirribossomos/metabolismoRESUMO
The present study aimed to explore the targets and mechanism of Mailuo Shutong Pills(MSP) in the treatment of ischemic stroke by network pharmacology, and verify the key targets through molecular docking and animal experiment, so as to provide a theoretical basis for the clinical application of MSP. The main chemical ingredients of MSP were obtained by searching against the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP) and relevant literature. The potential targets of the ingredients of MSP in treating ischemic stroke were obtained from SwissTargetPrediction and DisGeNET. Protein-protein interaction(PPI) network was analyzed in STRING and plotted in Cytoscape. Gene Ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis were carried out with DAVID. Molecular docking was simulated to determine the binding activity of active ingredients to key targets in AutoDock Vina. The mouse model of ischemic stroke was established. The mice were classified into a sham group, a model group, and an MSP group. After the administration, cerebral infarction volume was detected by 2,3,5-triphenyltetrazoliumchloride(TTC) staining, and Western blot was performed to determine the levels of phosphatidylinositol 3-kinase(PI3 K), protein kinase B(AKT), nuclear factor-κB(NF-κB) and their phosphorylated proteins. A total of 222 ingredients of MSP were screened out, including beta-sitosterol, quercetin, licochalcone B, and lupiwighteone, which acted on 701 targets. Totally 1 079 targets associated with ischemic stroke were retrieved, among which 192 common targets were shared by MSP and ischemic stroke. The key targets included AKT1, phosphatidylinositol 3-kinase catalytic subunit alpha(PIK3 CA), phosphatidylinositol 3-kinase regulatory subunit 1(PIK3 R1), and nuclear factor-κB p65 subunit(RELA), which were mainly involved in PI3 K/AKT, tumor necrosis factor(TNF), and NF-κB signaling pathways. The results of molecular docking revealed that PI3 K, AKT1, and RELA had good binding ability to the active ingredients of MSP. The animal experiment results showed that compared with the model group, MSP decreased cerebral infarction volume, down-regulated the expression of p-NF-κB, and up-regulated the expression of p-PI3 K and p-AKT in mouse brain. In summary, the active ingredients in MSP may treat cerebral injury by activating PI3 K/AKT signaling pathway and inhibiting NF-κB signaling pathway.
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Medicamentos de Ervas Chinesas , AVC Isquêmico , Animais , Camundongos , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/genética , AVC Isquêmico/tratamento farmacológico , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/genética , Infarto Cerebral , Medicamentos de Ervas Chinesas/farmacologiaRESUMO
Amphiphilic graft copolymers exhibit fascinating self-assembly behaviors. Their molecular architectures significantly affect the morphology and functionality of the self-assemblies. Considering the potential application of amphiphilic graft copolymers in the fabrication of nanocarriers, it is essential to synthesize well-defined graft copolymers with desired functional groups. Herein, the Passerini reaction and molecular recognition are introduced to the synthesis of functional thermoresponsive graft copolymers. A bifunctional monomer 2-((adamantan-1-yl)amino)-1-(4-((2-bromo-2-methylpropanoyl)oxy)phenyl)-2-oxoethyl methacrylate (ABMA) with a bromo group for atom transfer radical polymerization (ATRP) and an adamantyl group for molecular recognition is synthesized through the Passerini reaction. The graft copolymers are prepared by reversible addition-fragmentation transfer (RAFT) copolymerization of ABMA and oligo(ethylene glycol) methyl ether methacrylate (OEGMA) followed by RAFT end group removal and ATRP of di(ethylene glycol)methyl ether methacrylate (DEGMA) initiated by the ABMA units. The graft copolymer P(OEGMA-co-ABMA)-g-PDEGMA can be functionalized with ß-cyclodextrin modified peptides, affording a thermoresponsive biohybrid graft copolymer. At a temperature above its lower critical solution temperature, the biohybrid graft copolymer self-assembles into peptide-modified polymersomes.
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Metacrilatos , Polímeros , Micelas , Polimerização , TemperaturaRESUMO
A facile synthesis is reported of two-dimensional (2D) bimetallic (Fe/Co=1:2) metal-organic frameworks (MOF, ca. 2.2â nm thick) via simple stirring of the reaction mixture of Fe/Co salts and 1,4-benzene dicarboxylic acid (1,4-BDC) in the presence of triethylamine and water at room temperature. The mechanism of the 2D, rather than bulk, MOF was revealed by studying the role of each component in the reaction mixture. It was found that these 2D MOF-Fe/Co(1:2) exhibited excellent electrocatalytic activity for the oxygen evolution reaction (OER) under basic conditions. The electrocatalytic mechanism was disclosed via both experimental results and density functional theory (DFT) calculation. The 2D morphology and co-doping of Fe/Co contributed to the superior OER performance of the 2D MOF-Fe/Co(1:2). The simple and efficient synthetic method is suitable for the mass production and future commercialization of functional 2D MOF with low cost and high yield.
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A new method of stimuli-responsive proteinosome fabrication with the shell cross-linked micelle as a template is reported in this research. A thermoresponsive diblock copolymer poly[di(ethylene glycol) methyl ether methacrylate]-b-poly[poly(ethylene glycol) methyl ether methacrylate-co-pyridyl disulfide methacrylamide] [PDEGMA-b-P(PEGMA-co-PDSMA)] was synthesized and self-assembled into micelles with PDEGMA cores and P(PEGMA-co-PDSMA) shells at the temperature above its lower critical solution temperature (LCST). Reduced bovine serum albumin (BSA) molecules with six thiol groups were used to cross-link the shells of the micelles by reacting with the pendant pyridyl disulfide groups on the P(PEGMA-co-PDSMA) block. At a temperature below the LCST of the polymer, the PDEGMA cores were dissolved in water, affording proteinosomes with a size of about 50 nm and capsule-like structures. The proteinosome was also thermoresponsive with a phase transition temperature at 35 °C. The fabrication of the proteinosome had no obvious influence on the structure and activity of BSA, and BSA retained most of its secondary structure and esterase-like activity. Because the BSA molecules were connected to the polymer chains through disulfide bonds, they could be released upon addition of dithiothreitol. The in vitro cell viability evaluation and the cellular uptake assay demonstrated that the proteinosome showed low toxicity to NIH 3T3 and 4T1 cells and could be internalized into the 4T1 cells.
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Micelas , Polímeros , Animais , Bovinos , Dissulfetos , Soroalbumina Bovina , TemperaturaRESUMO
In this study, UiO-66-NH2 metal-organic framework (MOF) nanoparticles with peroxidase and oxidase mimetic activities were incorporated into a chitosan (CS) matrix by a simple and environmentally friendly method. The UiO-66-NH2/CS composite membrane possesses the peroxidase mimicking activity in the presence of traces of H2O2, thus resulting in good antibacterial properties. Intriguingly, 30 min of UV pre-irradiation of the UiO-66-NH2/CS composite membrane, in the absence of H2O2, still leads to a good antibacterial activity. This was attributed to the oxidase mimetic activity and the peroxidase mimicking activity of UiO-66-NH2. In such a way, the side effects of direct exposure to UV irradiation and H2O2 can be avoided for wound-healing treatments. The antibacterial mechanism was further proved by antibacterial experiments, TMB·2HCl color development experiments, reactive oxygen species generation tests and electron spin resonance tests. As a potential medical antibacterial dressing, in vitro membranes were also investigated.