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1.
Nat Commun ; 12(1): 5243, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34475406

RESUMO

Peroxisome, a special cytoplasmic organelle, possesses one or more kinds of oxidases for hydrogen peroxide (H2O2) production and catalase for H2O2 degradation, which serves as an intracellular H2O2 regulator to degrade toxic peroxides to water. Inspired by this biochemical pathway, we demonstrate the reactive oxygen species (ROS) induced tumor therapy by integrating lactate oxidase (LOx) and catalase (CAT) into Fe3O4 nanoparticle/indocyanine green (ICG) co-loaded hybrid nanogels (designated as FIGs-LC). Based on the O2 redistribution and H2O2 activation by cascading LOx and CAT catalytic metabolic regulation, hydroxyl radical (·OH) and singlet oxygen (1O2) production can be modulated for glutathione (GSH)-activated chemodynamic therapy (CDT) and NIR-triggered photodynamic therapy (PDT), by manipulating the ratio of LOx and CAT to catalyze endogenous lactate to produce H2O2 and further cascade decomposing H2O2 into O2. The regulation reactions of FIGs-LC significantly elevate the intracellular ROS level and cause fatal damage to cancer cells inducing the effective inhibition of tumor growth. Such enzyme complex loaded hybrid nanogel present potential for biomedical ROS regulation, especially for the tumors with different redox state, size, and subcutaneous depth.


Assuntos
Antineoplásicos/farmacologia , Nanogéis/química , Peroxissomos/enzimologia , Fotoquimioterapia/métodos , Animais , Antineoplásicos/química , Catalase/química , Catalase/metabolismo , Catálise , Linhagem Celular Tumoral , Óxido Ferroso-Férrico/química , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Verde de Indocianina/química , Camundongos , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Oxigênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral/efeitos dos fármacos
2.
Adv Mater ; 33(40): e2103174, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34418193

RESUMO

High-strength and reversible adhesion technology, which is a universal phenomenon in nature but remains challenging for artificial synthesis, is essential for the development of modern science. Existing adhesive designs without interface versatility hinder their application to arbitrary surfaces. Bioinspired by creeper suckers, a crystal-fiber reinforced polymer gel adhesive with ultrastrong adhesion strength and universal interface adaptability is creatively prepared via introducing a room-temperature crystallizable solvent into the polymer network. The gel adhesive formed by hydrogen bonding interaction between crystal fibers and polymer network can successfully realize over 9.82 MPa reversible adhesion strength for rough interface and 406.87 J m-2 peeling toughness for skin tissue. In situ anchoring is achieved for adapting to different geometrical surfaces. The adhesion performance can be significantly improved with the further increase of the interfacial roughness and hydrophilicity, whose dissipation mechanism is simulated by finite element analysis. The melting-crystallization equilibrium of the crystal fibers is proved by synchrotron radiation scattering. Accordingly, reversible phase-transition triggered by light and heat can realize the controlled adhere-detach recycle. Later adjustments to the monomers or crystals are expected to broaden its applications to various fields such as bioelectronics, electronic processing, and machine handling.

3.
Angew Chem Int Ed Engl ; 60(36): 19982-19987, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34173310

RESUMO

The in situ gelation of injectable precursors is desirable in the field of tissue regeneration, especially in the context of irregular defect filling. The current driving forces for fast gelation include the phase-transition of thermally sensitive copolymers, click chemical reactions with tissue components, and metal coordination effect. However, the rapid formation of tough hydrogels remains a challenge. Inspired by aerobic metabolism, we herein propose a tissue-fluid-triggered cascade enzymatic polymerization process catalyzed by glucose oxidase and ferrous glycinate for the ultrafast gelation of acryloylated chondroitin sulfates and acrylamides. The highly efficient production of carbon radicals and macromolecules contribute to rapid polymerization for soft tissue augmentation in bone defects. The copolymer hydrogel demonstrated the regeneration-promoting capacity of cartilage. As the first example of using artificial enzyme complexes for in situ polymerization, this work offers a biomimetic approach to the design of strength-adjustable hydrogels for bio-implanting and bio-printing applications.

4.
BMC Plant Biol ; 21(1): 223, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001006

RESUMO

BACKGROUND: Rose is an important economic crop in horticulture. However, its field growth and postharvest quality are negatively affected by grey mould disease caused by Botrytis c. However, it is unclear how rose plants defend themselves against this fungal pathogen. Here, we used transcriptomic, metabolomic and VIGS analyses to explore the mechanism of resistance to Botrytis c. RESULT: In this study, a protein activity analysis revealed a significant increase in defence enzyme activities in infected plants. RNA-Seq of plants infected for 0 h, 36 h, 60 h and 72 h produced a total of 54 GB of clean reads. Among these reads, 3990, 5995 and 8683 differentially expressed genes (DEGs) were found in CK vs. T36, CK vs. T60 and CK vs. T72, respectively. Gene annotation and cluster analysis of the DEGs revealed a variety of defence responses to Botrytis c. infection, including resistance (R) proteins, MAPK cascade reactions, plant hormone signal transduction pathways, plant-pathogen interaction pathways, Ca2+ and disease resistance-related genes. qPCR verification showed the reliability of the transcriptome data. The PTRV2-RcTGA1-infected plant material showed improved susceptibility of rose to Botrytis c. A total of 635 metabolites were detected in all samples, which could be divided into 29 groups. Metabonomic data showed that a total of 59, 78 and 74 DEMs were obtained for T36, T60 and T72 (T36: Botrytis c. inoculated rose flowers at 36 h; T60: Botrytis c. inoculated rose flowers at 60 h; T72: Botrytis c. inoculated rose flowers at 72 h) compared to CK, respectively. A variety of secondary metabolites are related to biological disease resistance, including tannins, amino acids and derivatives, and alkaloids, among others; they were significantly increased and enriched in phenylpropanoid biosynthesis, glucosinolates and other disease resistance pathways. This study provides a theoretical basis for breeding new cultivars that are resistant to Botrytis c. CONCLUSION: Fifty-four GB of clean reads were generated through RNA-Seq. R proteins, ROS signalling, Ca2+ signalling, MAPK signalling, and SA signalling were activated in the Old Blush response to Botrytis c. RcTGA1 positively regulates rose resistance to Botrytis c. A total of 635 metabolites were detected in all samples. DEMs were enriched in phenylpropanoid biosynthesis, glucosinolates and other disease resistance pathways.


Assuntos
Botrytis/patogenicidade , Resistência à Doença/genética , Glucosinolatos/biossíntese , Glucosinolatos/genética , Imunidade Vegetal/genética , Rosa/genética , Rosa/microbiologia , China , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Horticultura , Interações Hospedeiro-Patógeno/genética , Metaboloma , Reprodutibilidade dos Testes , Transcriptoma
5.
Acc Chem Res ; 54(5): 1274-1287, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33570397

RESUMO

Enzymes, a class of highly efficient and specific catalysts in Nature, dictate a myriad of reactions that constitute various cascades in biological systems. There is growing evidence that many cellular reactions within metabolic pathways are catalyzed by matrix-associated multienzyme complexes, not via the free enzymes, verifying the vital effects of microenvironmental organization, which would reveal implications for the high efficiency, specificity, and regulation of metabolic pathways. The extracellular matrix (ECM), as the noncellular component, is composed of various proteins such as collagens, laminins, proteoglycans, and remodeling enzymes, playing the key role in tissue architecture and homeostasis. Hydrogels are defined as highly hydrated polymer materials and maintain structural integrity by physical and chemical force, which are thought of as the most suitable materials for matching the chemical, physical, and mechanical properties with natural ECM. As one specific type of soft and wet materials, hydrogels are suitable three-dimensional carriers to locally confine bioactive guests, such as enzymes, for molecular-level biological interactions. The efficient cascade catalysis can be realized by enzyme-laden hydrogels, which can potentially interact with cells and tissues by material-to-biology communication. In this Account, we present recent progress on the preparation of enzymatic bioactive hydrogels, including in situ coassembly, in situ cross-linking strategy, and in situ enzymatic radical polymerization technology, further promoting their applications on biomedical tissue engineering, biocatalytic health monitoring, and therapeutic research. First, we provide a brief introduction of the basic concept related to an enzymatic strategy in living systems and the importance of bioinspired enzyme-laden bioactive hydrogel systems. We discuss the difficulties of the fabrication of a bioactive hydrogel with a high catalytic efficiency, thereby providing the novel molecular design and regulation based on a noncovalent coassembly and in situ self-immobilization strategy to obtain the compartmentalized enzyme-laden structure. Then the applications of an enzyme-laden bioactive hydrogel for biocatalytic applications are discussed in detail. The enzyme-laden bioactive hydrogel can maintain the favorable perception and regulation behavior of enzymes with optimal enzymatic efficacy between this confined hydrogel network and a surrounding environment. A highlight to the advances in the responsively biocatalytic monitoring and regulation of bioactive hydrogel, including the enzymatic biomedical tissue engineering and health monitoring, enzymatic regulation of tumor reactive oxygen species and therapeutic research are given. Finally, the outlook of open challenges and future developments of this rapidly evolving field is provided. This Account with highlights of diverse enzyme-laden bioactive hydrogel systems not only provides interesting insights to understand the cascade enzymatic strategy of life but also inspires to broaden and enhance the molecular-level material design and bioapplications of existing enzymatic materials in chemistry, materials science, and biology.


Assuntos
Enzimas/metabolismo , Hidrogéis/metabolismo , Animais , Biocatálise , Enzimas/química , Humanos , Hidrogéis/química , Engenharia Tecidual
6.
Artigo em Inglês | MEDLINE | ID: mdl-33092504

RESUMO

BACKGROUND: As artificial intelligence and big data analysis develop rapidly, data privacy, especially patient medical data privacy, is getting more and more attention. OBJECTIVE: To strengthen the protection of private data while ensuring the model training process, this article introduces a multi-Blockchain-based decentralized collaborative machine learning training method for medical image analysis. In this way, researchers from different medical institutions are able to collaborate to train models without exchanging sensitive patient data. METHOD: Partial parameter update method is applied to prevent indirect privacy leakage during model propagation. With the peer-to-peer communication in the multi-Blockchain system, a machine learning task can leverage auxiliary information from another similar task in another Blockchain. In addition, after the collaborative training process, personalized models of different medical institutions will be trained. RESULTS: The experimental results show that our method achieves similar performance with the centralized model-training method by collecting data sets of all participants and prevents private data leakage at the same time. Transferring auxiliary information from similar task on another Blockchain has also been proven to effectively accelerate model convergence and improve model accuracy, especially in the scenario of absence of data. Personalization training process further improves model performance. CONCLUSION: Our approach can effectively help researchers from different organizations to achieve collaborative training without disclosing their private data.

7.
Small ; 16(44): e2004091, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33051993

RESUMO

Although plenty of progress and achievements are made on hydrogel electrolyte researches, the inherent inferior low-temperature performance of hydrogel electrolyte is still a severe challenge for wider application on the energy storage devices, due to the high content of water within hydrogel. Herein, an enhanced solar-driven-heating composite hydrogel electrolyte and a solar-driven-heating graphene based micro-supercapacitor are developed utilizing the photothermal conversion ability and self-initiation of MoS2 nanosheets and additional Hofmeister effect. The MoS2 composite hydrogel electrolyte not only improves the reliability of micro-supercapacitor owing to its splendid mechanical properties, but also endows the micro-supercapacitor with superior low-temperature electrochemical performance and broadens its operating environment to a much lower temperature (-56 °C), which should be attributed to the excellent ability in converting endless solar energy into required thermal energy. These efforts would construct a new application platform for solar energy conversion and present an efficient method to structure severe-cold resistant solid state energy storage devices for next-generation.

8.
Adv Mater ; 32(30): e2000189, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32567056

RESUMO

Bioelectronic platforms convert biological signals into electrical signals by utilizing biocatalysts that provide tools to monitor the activity of cells and tissues. Traditional conducting materials such as solid conductors and conducting polymers are confronted with a great challenge in sophisticated production processes and mismatch at biological tissues-machine interfaces. Furthermore, the biocatalyst, the key functional component in the electron-transfer reaction for bio-signal detection denatures easily in an ionic conductive solution. Herein, a bionic strategy is elaborately developed to synthesize an ionohydrogel bioelectronic platform that possesses extracellular-matrix-like habitat by employing hydrated ionic liquids (HILs) as ionic solvent and bioprotectant. This strategy realizes an integration of ionic and enzymatic electronic circuits and minimization of the disparities between tissues and artificial machines. The Hofmeister effect of HILs on enzyme proteins and polymer chains ensures the high bioactivity of the enzymes and greatly improves the mechanical properties of the ionohydrogels. Moreover, hydrogen bonds formed by ILs, water, and polymer chains greatly improve the water-retention of the ionohydrogel and give it more practical significance. Consequently, the promising ionohydrogel is partly printed and fabricated into wearable devices as a pain-free humoral components monitor and a wireless motion-sensor.

9.
Adv Mater ; 32(26): e2000366, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32430939

RESUMO

New-era soft microrobots for biomedical applications need to mimic the essential structures and collective functions of creatures from nature. Biocompatible interfaces, intelligent functionalities, and precise locomotion control in a collective manner are the key parameters to design soft microrobots for the complex bio-environment. In this work, a biomimetic magnetic microrobot (BMM) inspired by magnetotactic bacteria (MTB) with speedy motion response and accurate positioning is developed for targeted thrombolysis. Similar to the magnetosome structure in MTB, the BMM is composed of aligned iron oxide nanoparticle (MNP) chains embedded in a non-swelling microgel shell. Linear chains in BMMs are achieved due to the interparticle dipolar interactions of MNPs under a static magnetic field. Simulation results show that, the degree and speed of assembly is proportional to the field strength. The BMM achieves the maximum speed of 161.7 µm s-1 and accurate positioning control under a rotating magnetic field with less than 4% deviation. Importantly, the locomotion analyses of BMMs demonstrate the frequency-dependent synchronization under 8 Hz and asynchronization at higher frequencies due to the increased drag torque. The BMMs can deliver and release thrombolytic drugs via magneto-collective control, which is promising for ultra-minimal invasive thrombolysis.


Assuntos
Biomimética/métodos , Magnetossomos/química , Robótica , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Biomimética/instrumentação , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Compostos Férricos/química , Fibrinolíticos/química , Fibrinolíticos/metabolismo , Fibrinolíticos/uso terapêutico , Humanos , Campos Magnéticos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Nanopartículas Metálicas/química , Neutrófilos/citologia , Neutrófilos/metabolismo , Ratos , Tromboembolia/tratamento farmacológico , Ativador de Plasminogênio Tecidual/química , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tecidual/uso terapêutico , Cordão Umbilical/citologia
10.
Angew Chem Int Ed Engl ; 59(29): 11748-11753, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32243658

RESUMO

The design of enzyme mimics from stable and nonprotein systems is especially attractive for applications in highly specific cancer diagnosis and treatment, and it has become an emerging field in recent years. Herein, metal crosslinked polymeric nanogels (MPGs) were prepared using FeII ion coordinated biocompatible acryloyl-lysine polymer brushes obtained from an enzyme-catalyzed atomic transfer radical polymerization (ATRPase) method. The monoatomic and highly dispersed Fe ions in the MPGs serve as efficient crosslinkers of the gel network, and also as active centers of multienzyme mimics of superoxide dismutase (SOD) and peroxidase (POD). The catalytic activities were compared to those of conventional Fe-based nanozymes. Studies on both cells and animals verify that efficient reactive oxygen species (ROS) responsive biofluorescence imaging can be successfully realized using the MPGs.


Assuntos
Complexos Multienzimáticos/química , Nanoestruturas/química , Polimerização , Animais , Catálise , Linhagem Celular , Reagentes para Ligações Cruzadas , Compostos Ferrosos/química , Géis , Humanos , Nanogéis , Imagem Óptica , Peroxidases/química , Polietilenoglicóis , Polietilenoimina , Espécies Reativas de Oxigênio , Superóxido Dismutase/química
11.
Environ Sci Pollut Res Int ; 27(17): 21299-21310, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32266624

RESUMO

Surface water suffering from nitrate (NO3-) contamination in karst area is not only harmful to human health as drinking water but can also affect the process of carbonate rock weathering, so it is crucial to trace the sources and transformations of NO3- in karst surface water. In this study, an investigation of water chemical data and NO3- isotopes (δ15N and δ18O) was used to elucidate the transformations of NO3- and quantify a proportional apportionment of NO3- sources of individual potential sources (incl. soil organic nitrogen (SON), atmospheric precipitation (AP), manure and sewage wastes (M&S), and chemical fertilizer (CF)) in the Lijiang River (typical karst surface water), Guilin, Southwest China. δ15N-NO3- and δ18O-NO3- values of water samples from the Lijiang River range from 2.14 to 13.50‰ (mean, 6.59‰) and from - 2.44 to 6.97‰ (mean, 3.76‰), respectively. A positive correlation between Cl- and NO3- but no correlations between NO3- and δ15N-NO3- or δ18O-NO3- are found and the δ18O-NO3- values fitted the theoretical δ18O-NO3- values produced from nitrification, suggesting that the genesis of NO3- in waters of the Lijiang River is affected by nitrification processes and the mixing process has a major effect on NO3- transportation. Results of the Bayesian stable isotope mixing model show that the M&S and SON are the main NO3- source through the whole year (accounting for ~ 61% and 65% of the total NO3- in the wet and dry season, respectively), followed by CF (~ 29%). Furthermore, we find that nitrification of nitrogen in fertilizers, soil, and manure and sewage can promote the carbonate rock weathering. The estimated contribution of such nitrification to the weathering of carbonate rocks accounts for about 11% of the total carbonate rock weathering flux (calculated by HCO3-) in the Lijiang River. This finding indicates that the weathering of carbonate rock is probably affected by nitrogen nitrification processes in karst catchment.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água/análise , Teorema de Bayes , China , Nitratos/análise , Isótopos de Nitrogênio/análise , Rios
12.
Nat Commun ; 11(1): 1843, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32296049

RESUMO

With the world's focus on wearable electronics, the scientific community has anticipated the plasticine-like processability of electrolytes and electrodes. A bioinspired composite of polymer and phase-changing salt with the similar bonding structure to that of natural bones is a suitable electrolyte candidate. Here, we report a water-mediated composite electrolyte by simple thermal mixing of crystallohydrate and polymer. The processable phase-change composites have significantly high mechanical strength and high ionic mobility. The wide operating voltage range and high faradic capacity of the composite both contribute to the maximum energy density. The convenient assembly and high thermal-shock resistance of our device are due to the mechanical interlocking and endothermic phase-change effect. As of now, no other non-liquid electrolytes, including those made from ceramics, polymers, or hydrogels, possess all of these features. Our work provides a universal strategy to fabricate various thermally manageable devices via phase-change electrolytes.

13.
Front Chem ; 8: 36, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117869

RESUMO

Polymer hydrogels are ideal bioprinting scaffolds for cell-loading and tissue engineering due to their extracellular-matrix-like structure. However, polymer hydrogels that are easily printed tend to have poor strength and fragile properties. The gradually polymerized reinforcement after hydrogel printing is a good method to solve the contradiction between conveniently printed and high mechanical strength requirement. Here, a new succinct approach has been developed to fabricate the printable composite hydrogels with tunable strength. We employed the HRP@GOx dual enzyme system to initiate the immediate crosslinking of chondroitin sulfate grafted with tyrosine and the gradual polymerization of monomers to form the composite hydrogels. The detailed two-step gelation mechanism was confirmed by the Fluorescence spectroscopy, Electron paramagnetic resonance spectroscopy and Gel permeation chromatography, respectively. The final composite hydrogel combines the merits of enzymatic crosslinking hydrogels and polymerized hydrogels to achieve adjustable mechanical strength and facile printing performance. The dual-enzyme regulated polymer composite hydrogels are the promising bioscaffolds as organoid, implanted materials, and other biomedical applications.

15.
Angew Chem Int Ed Engl ; 59(9): 3732-3738, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-31834981

RESUMO

Neutrophils can responsively release reactive oxygen species (ROS) to actively combat infections by exogenous stimulus and cascade enzyme catalyzed bio-oxidation. A supramolecular nanogel is now used as an artificial neutrophil by enzymatic interfacial self-assembly of peptides (Fmoc-Tyr(H2 PO3 )-OH) with magnetic nanoparticles (MNPs) and electrostatic loading of chloroperoxidase (CPO). The MNPs within the nanogel can elevate H2 O2 levels in cancer cells under programmed alternating magnetic field (AMF) similar to the neutrophil activator, and the loaded CPO within protective peptides nanolayer converts the H2 O2 into singlet oxygen (1 O2 ) in a sustained manner for neutrophil-inspired tumor therapy. As a proof of concept study, both the H2 O2 and 1 O2 in cancer cells increase stepwise under a programmed alternating magnetic field. An active enzyme dynamic therapy by magnetically stimulated oxygen stress and sustained enzyme bio-oxidation is thus shown with studies on both cells and animals.


Assuntos
Cloreto Peroxidase/metabolismo , Nanopartículas de Magnetita/química , Nanogéis/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cloreto Peroxidase/química , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Campos Magnéticos , Camundongos , Nanogéis/uso terapêutico , Nanogéis/toxicidade , Neoplasias/tratamento farmacológico , Neoplasias/mortalidade , Neoplasias/patologia , Neutrófilos/química , Neutrófilos/imunologia , Tamanho da Partícula , Peptídeos/química , Oxigênio Singlete/química , Oxigênio Singlete/metabolismo , Eletricidade Estática , Taxa de Sobrevida , Transplante Heterólogo
16.
J Mater Chem B ; 7(40): 6195-6201, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31565719

RESUMO

Hybrid hydrogels combining polymers and low-molecular-weight gelators (LMWGs) are promising soft materials. Self-assembled LMWG-based supramolecular networks via noncovalent interactions exhibit excellent reversible thixotropy, which are usually incorporated into polymer gel networks generating functional double network hybrid hydrogels. In this study, we used enzyme-mediated polymerization and post-self-assembly for the one-pot preparation of LMWG-based hybrid hydrogels which consist of a covalently cross-linked polyacrylamide as the first chemical network and post-self-assembled DBS-COOH as the second supramolecular network. The gelation processes are monitored by the EPR measurement and 1H NMR characterization. The DBS-COOH gel network endows the hybrid gel with a well-controlled release behaviour of an anti-inflammatory drug-diclofenac sodium (DCF). Further in vivo wound healing experiments elucidated that the hybrid gel is a promising candidate material for biomedical applications. The enzymatic one-pot preparation principle will provide a unique viewpoint for fabricating functional LMWG/polymer hybrid hydrogels.


Assuntos
Hidrogéis/química , Polímeros/química , Sorbitol/análogos & derivados , Cicatrização/efeitos dos fármacos , Resinas Acrílicas/química , Animais , Proliferação de Células , Polimerização , Ratos , Ratos Sprague-Dawley , Sorbitol/química , Sorbitol/farmacologia
17.
ACS Nano ; 13(8): 9198-9205, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31330102

RESUMO

A Ti3(AlxCu1-x)C2 phase with Cu atoms with a degree of ordering in the A plane is synthesized through the A site replacement reaction in CuCl2 molten salt. The weakly bonded single-atom-thick Cu layers in a Ti3(AlxCu1-x)C2 MAX phase provide actives sites for catalysis chemistry. As-synthesized Ti3(AlxCu1-x)C2 presents unusual peroxidase-like catalytic activity similar to that of natural enzymes. A fabricated Ti3(AlxCu1-x)C2/chitosan/glassy carbon electrode biosensor prototype also exhibits a low detection limit in the electrochemical sensing of H2O2. These results have broad implications for property tailoring in a nanolaminated MAX phase by replacing the A site with late transition elements.

18.
Adv Mater ; 31(30): e1900248, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31183940

RESUMO

Although nonliquid electrolytes have been developed rapidly under the condition of safe demand of energy storage devices, the inherent weaknesses in ionic conductivity, mechanical properties, or interfacial compatibility severely hinder their application under a harsh environment. Inspired by the hybridized characteristics of composite materials and the potential advantages of hydrated crystals, a processable crystal-type gel electrolyte with good comprehensive performance via the dissolution-crystallization transition of NaAc within hydrogel is creatively prepared. The use of NaAc crystal within a hydrogel leads to nearly 26 000 times greater modulus (474.24 MPa) and higher operating voltage (2.0 V) than the hydrogel without the crystal. The reliable supercapacitor using this electrolyte can work in extreme environment (-40 to 80 °C, even in the fire or in liquid nitrogen within a short time) benefiting from its phase-transition capacity. This investigation offers a facile and versatile way to construct an ideal gel electrolyte for next-generation energy storage devices.

19.
Huan Jing Ke Xue ; 40(3): 1222-1235, 2019 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087969

RESUMO

This study was done to understand the diel variation and factors influencing the hydrochemistry of the Lijing River in different seasons. This is a typical medium river located at Guilin City in the Guangxi Zhuang Autonomous Region, SW China. The Shengli site was selected for this study. Two-day monitoring work with a high resolution rate logger and high frequency sampling at 2 hour intervals was conducted at the Shengli site of the Lijiang River in summer and autumn separately. Physical and hydrogeochemical parameters including pH, dissolved oxygen (DO), water temperature (T), electrical conductivity (EC), dissolved inorganic carbon (DIC), isotopes, and other chemical parameters were examined. The results show that:① the physical and hydrochemical parameters[T, pH, DO, SIC, EC, p (CO2)] and major ions (HCO3-, Ca2+) at the Shengli site displayed regular diel variation during monitoring. The data for T, pH, DO, and SIC increased in daylight and decreased at night, while the data for Ca2+, HCO3-, EC, and p (CO2) decreased in daylight and increased at night. ② The diurnal changes of nutrient elements (SO42-, NO3-, Cl-, Na+, Mg2+, and K+) at the Shengli site were mainly controlled by photosynthesis and respiration of aquatic plants, and showed the trend of decrease in daylight and increase at night. Due to the influence of a flood in mid-August 2017, the amount of diurnal variation in the nutrient element levels in summer was less than that in autumn. ③ The δ13CDIC increased in daylight and decreased at night both in summer and autumn, reflecting the influences of photosynthesis and precipitation. Under the influence of different root systems, soil microbial respiration intensity, and seasonal variation of river hydrological factors, the δ13CDIC in summer was generally lighter than that in autumn, with average values of -10.08‰ and -8.90‰, respectively. ④ The daily average fixation amount of karst carbon sink caused by aquatic plants was calculated to be 2.12 mmol·L-1 and 0.94 mmol·L-1 for Autumn and Summer, respectively. To sum up, there is a higher efficiency of karst carbon sink caused by aquatic plants in Autumn than that in Summer.

20.
Sci Rep ; 9(1): 5985, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30979937

RESUMO

Roses are important woody plants featuring a set of important traits that cannot be investigated in traditional model plants. Here, we used the restriction-site associated DNA sequencing (RAD-seq) technology to develop a high-density linkage map of the backcross progeny (BC1F1) between Rosa chinensis 'Old Blush' (OB) and R. wichuraiana 'Basyes' Thornless' (BT). We obtained 643.63 million pair-end reads and identified 139,834 polymorphic tags that were distributed uniformly in the rose genome. 2,213 reliable markers were assigned to seven linkage groups (LGs). The length of the genetic map was 1,027.425 cM in total with a mean distance of 0.96 cM per marker locus. This new linkage map allowed anchoring an extra of 1.21/23.14 Mb (12.18/44.52%) of the unassembled OB scaffolds to the seven reference pseudo-chromosomes, thus significantly improved the quality of assembly of OB reference genome. We demonstrate that, while this new linkage map shares high collinearity level with strawberry genome, it also features two chromosomal rearrangements, indicating its usefulness as a resource for understanding the evolutionary scenario among Rosaceae genomes. Together with the newly released genome sequences for OB, this linkage map will facilitate the identification of genetic components underpinning key agricultural and biological traits, hence should greatly advance the studies and breeding efforts of rose.


Assuntos
Mapeamento Cromossômico , Genoma de Planta , Rosa/genética , Mapeamento Cromossômico/métodos , Fragaria/genética , Marcadores Genéticos , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
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