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1.
J Colloid Interface Sci ; 666: 529-539, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613975

RESUMO

Elastic carbon aerogels have promising applications in the field of wearable sensors. Herein, a new strategy for preparing carbon aerogels with excellent compressive strength and strain, shape recovery, and fatigue resistance was proposed based on the structure design and carbonization optimization of nanocellulose-based precursor aerogels. By the combination of directional freezing and zinc ion cross-linking, bacterial cellulose (BC)/alginate (SA) composite aerogels with high elasticity and compressive strength were first achieved. The existance of zinc ions also significantly improved the carbon retention rate and inhibited structural shrinkage, thus making the carbon aerogels retain ultra-high elasticity and fatigue resistance after compression. Moreover, the carbon aerogel possessed excellent piezoresistive pressure sensing performance with a wide detection range of 0-7.8 kPa, high sensitivity of 11.04 kpa-1, low detection limit (2 % strain), fast response (112 ms), and good durability (over 1,000 cycles). Based on these excellent properties, the carbon aerogel pressure sensors were further successfully used for human motion monitoring, from joint motion to and speech recognition.


Assuntos
Alginatos , Carbono , Celulose , Elasticidade , Géis , Dispositivos Eletrônicos Vestíveis , Carbono/química , Géis/química , Humanos , Celulose/química , Alginatos/química , Anisotropia , Tamanho da Partícula , Propriedades de Superfície , Zinco/química
2.
Int J Biol Macromol ; 263(Pt 1): 130176, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368977

RESUMO

Smart gating membranes have drawn much attention due to the controllable pore structure. Herein, a smart gating membrane with dual responsiveness was prepared from bacteria cellulose (BC) grafted with pH- and temperature-responsive polymers. By external stimulation, the average pore size of the membrane can be controlled from 33.75 nm to 144.81 nm, and the pure water flux can be regulated from 342 to 2118 L·m-2·h-1 with remarkable variation in the pH range of 1-11 and temperature range of 20-60 °C. The adjustability of pore size is able to achieve the gradient selective separation of particles and polymers with different sizes. In addition, owing to the underwater superoleophobicity and the nanoscale pore structure, the membrane separation efficiencies of emulsified oils are higher than 99 %. Moreover, the controllable pore size endows the membrane with good self-cleaning performance. This nanocellulose-based smart gating membrane has potential applications in the fields of controllable permeation, selective separation, fluid transport, and drug/chemical controlled release systems.


Assuntos
Polímeros , Água , Temperatura , Água/química , Polímeros/química , Celulose , Concentração de Íons de Hidrogênio
3.
Sensors (Basel) ; 24(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38339491

RESUMO

Optical coherence tomography angiography (OCTA) offers critical insights into the retinal vascular system, yet its full potential is hindered by challenges in precise image segmentation. Current methodologies struggle with imaging artifacts and clarity issues, particularly under low-light conditions and when using various high-speed CMOS sensors. These challenges are particularly pronounced when diagnosing and classifying diseases such as branch vein occlusion (BVO). To address these issues, we have developed a novel network based on topological structure generation, which transitions from superficial to deep retinal layers to enhance OCTA segmentation accuracy. Our approach not only demonstrates improved performance through qualitative visual comparisons and quantitative metric analyses but also effectively mitigates artifacts caused by low-light OCTA, resulting in reduced noise and enhanced clarity of the images. Furthermore, our system introduces a structured methodology for classifying BVO diseases, bridging a critical gap in this field. The primary aim of these advancements is to elevate the quality of OCTA images and bolster the reliability of their segmentation. Initial evaluations suggest that our method holds promise for establishing robust, fine-grained standards in OCTA vascular segmentation and analysis.


Assuntos
Oclusão da Veia Retiniana , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Reprodutibilidade dos Testes , Oclusão da Veia Retiniana/diagnóstico , Vasos Retinianos/diagnóstico por imagem , Angiografia
4.
Zhongguo Zhong Yao Za Zhi ; 49(2): 361-369, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38403312

RESUMO

The 4-coumarate: CoA ligase(4CL) is a key enzyme in the upstream pathway of phenylpropanoids such as flavonoids, soluble phenolic esters, lignans, and lignins in plants. In this study, 13 4CL family members of Arabidopsis thaliana were used as reference sequences to identify the 4CL gene family candidate members of Isatis indigotica from the reported I. indigotica genome. Further bioinformatics analysis and analysis of the expression pattern of 4CL genes and the accumulation pattern of flavonoids were carried out. Thirteen 4CL genes were obtained, named Ii4CL1-Ii4CL13, which were distributed on chromosomes 1, 2, 3, 4, and 6. The analysis of the gene structure and conserved structural domains revealed the intron number of I. indigotica 4CL genes was between 1 and 12 and the protein structural domains were highly conserved. Cis-acting element analysis showed that there were multiple response elements in the promoter sequence of I. indigotica 4CL gene family, and jasmonic acid had the largest number of reaction elements. The collinearity analysis showed that there was a close relationship between the 4CL gene family members of I. indigotica and A. thaliana. As revealed by qPCR results, the expression analysis of the 4CL gene family showed that 10 4CL genes had higher expression levels in the aboveground part of I. indigotica. The content assay of flavonoids in different parts of I. indigotica showed that flavonoids were mainly accumulated in the aboveground part of plants. This study provides a basis for further investigating the roles of the 4CL gene family involved in the biosynthesis of flavonoids in I. indigotica.


Assuntos
Isatis , Ligases , Ligases/genética , Isatis/genética , Regiões Promotoras Genéticas , Plantas/metabolismo , Flavonoides , Coenzima A Ligases/genética , Coenzima A Ligases/química , Coenzima A Ligases/metabolismo
5.
Int J Biol Macromol ; 256(Pt 1): 128326, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000571

RESUMO

Recent reports had shown that microplastics could be transferred to organisms through various channels, severely and adversely affecting organisms' health and their physiological functions. Therefore, there remained an urgency to adopt an effective and environmentally friendly method to extract microplastics from water. In this paper, a cationic-modified d-DCPG aerogel with a three-dimensional network structure was successfully prepared by a directional freeze-drying technology in which double-aldehyde-modified cellulose nanofiber (CNF) was used as the matrix, betaine chloride hydrazide (GT) provided modification, and polyvinyl alcohol (PVA) provided cross-linking function. Aerogels had an excellent adsorption capacity (145.05 mg/g) for microplastics in aqueous environment, and when the pH was from 10 to 4, it exhibited an excellent adsorption efficiency from 90.01 % to 97.61 %; an excellent adsorption efficiency after 8 cycles (>89 %); pseudo-second-order kinetics and Freundlich adsorption isotherm had a high fitting effects on the adsorption process and adsorption results, respectively. And ultraviolet analysis also verified the occurrence of adsorption behavior. These results showed that d-DCPG aerogels had an excellent application prospects in microplastics removal in river, lake, reservoir, and marine environments.


Assuntos
Microplásticos , Plásticos , Adsorção , Aldeídos , Betaína , Cátions
6.
Int J Biol Macromol ; 255: 128188, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37977473

RESUMO

Petroleum-based plastics are useful but they pose a great threat to the environment and human health. It is highly desirable yet challenging to develop sustainable structural materials with excellent mechanical and optical properties for plastic replacement. Here, we report a simple and efficient method to manufacture high-performance all-biobased structural materials from cellulosic wood skeleton (WS) and gelatin via oxidation and densification. Specifically, gelatin was grafted to the oxidized cellulose wood skeletons (DAWS) and then physically crosslinked via Tannic acid (TA), resulting in a significant enhancement of the material properties. Notably, only a mild pressure was applied during the drying process to form a densified TA/Gelatin/transparent wood film(TWF). The developed TA/Gelatin/TWF (thickness:100 ± 12 µm) exhibited a desirable combination of high strength (∼154.59 MPa), light transmittance (86.2 % at 600 nm), low haze (16.7 %), high water stability (wet strength: ∼130.13 MPa) and ultraviolet blocking efficacy which surpass most of the petroleum-based plastics. In addition, due to the all bio-based origins (wood and gelatin), TA/Gelatin/TWF are easily biodegradable under natural conditions, leading to less impact on the environment. These findings would hold promises for exploring high-quality all bio-based wood composites as eco-friendly alternatives to substitute plastics with wide applications, e.g. anti-counterfeiting, UV protection, and flexible electricals.


Assuntos
Celulose Oxidada , Petróleo , Humanos , Gelatina , Madeira
7.
Int J Biol Macromol ; 250: 126059, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37544557

RESUMO

The ultraviolet (UV) blocking performance of current bio-based devices is always limited by delignification and exploited chemical treatment. Lignocellulosic nanofibril (LCNF) is a promising green alternative that could efficiently impede UV radiation. Herein, we proposed a robust LCNF film that achieved 99.8 ± 0.19 % UVB blocking, 96.1 ± 0.23 % UVA blocking, and was highly transparent without complex chemical modification. Compared to conventional lignin composites, this LCNF method involves 29.5 ± 2.31 % lignin content directly extracted from bamboo as a broad-spectrum sun blocker. This bamboo-based LCNF film revealed an excellent tensile strength of 94.9 ± 3.6 MPa and outstanding stability, adapting to the natural environment's variability. The residual hemicellulose could also embed the link between lignin and cellulose, confirming high lignin content in the network. The connection between lignin and hemicelluloses in the cellulose network was explored and described for the fibrillation of lignocellulosic nanofibrils. This research highlights the promising development of LCNFs for UV protection and bio-based solar absorption materials.

8.
Int J Biol Macromol ; 248: 125973, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37495000

RESUMO

Conductive hydrogels are considered one of the most promising materials for preparing flexible sensors due to their flexible and extensible properties. However, conventional hydrogels' weak mechanical and isotropic properties are greatly limited in practical applications. Here, the internal structure of the hydrogel was regulated by pre-stretching synergistic ion crosslinking to construct a carboxymethyl cellulose-based double network-oriented hydrogel similar to muscle. The introduction of pre-stretching increased the tensile strength of the double-network hydrogel from 1.45 MPa to 4.32 MPa, and its light transmittance increased from 67.3 % to 84.5 %. In addition, the hydrogel's thermal stability and electrical conductivity were improved to a certain extent. Its good mechanical properties and conductive properties can be converted into stable electrical signal output during deformation. The carboxymethyl cellulose-based double network oriented hydrogels were further assembled as flexible substrates into flexible sensor devices. The hydrogel sensors can monitor simple joint movements as well as complex spatial movements, which makes them have potential application value in the research field of intelligent response electronic devices such as flexible wearables, intelligent strain sensing, and soft robots.


Assuntos
Carboximetilcelulose Sódica , Músculos , Condutividade Elétrica , Articulações , Hidrogéis
9.
Math Biosci Eng ; 20(7): 12404-12432, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37501448

RESUMO

This systematic review aims to investigate recent developments in the area of arc fault detection. The rising demand for electricity and concomitant expansion of energy systems has resulted in a heightened risk of arc faults and the likelihood of related fires, presenting a matter of considerable concern. To address this challenge, this review focuses on the role of artificial intelligence (AI) in arc fault detection, with the objective of illuminating its advantages and identifying current limitations. Through a meticulous literature selection process, a total of 63 articles were included in the final analysis. The findings of this review suggest that AI plays a significant role in enhancing the accuracy and speed of detection and allowing for customization to specific types of faults in arc fault detection. Simultaneously, three major challenges were also identified, including missed and false detections, the restricted application of neural networks and the paucity of relevant data. In conclusion, AI has exhibited tremendous potential for transforming the field of arc fault detection and holds substantial promise for enhancing electrical safety.

10.
World Neurosurg ; 178: e362-e370, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37482084

RESUMO

OBJECTIVE: To provide a precise description of the morphology and morphometry of the hypoglossal canal (HC) and its relationship with surrounding structures by using the epoxy sheet plastination technique. METHODS: Thirty human cadaveric heads were plastinated into 5 sets of gross transparent plastination slices and 43 sets of ultrathin plastination sections. The HC were examined at both macro- and micro levels in these plastination sections and the reconstructed 3-dimensional visualization model. RESULTS: The HC was an upward arched bony canal with a dumbbell-shaped lumen. According to the arched trajectory of its bottom wall, the HC could be divided into a medial ascending segment and a lateral descending segment. The thickness of the compact bone in the middle part of the HC was thinner than that at the intracranial and extracranial orifices. In 14 of 43 sides (32.6%), the posterior wall or the roof of the HC were disturbed by passing venous channels which communicated the posterior condylar emissary vein and the inferior petroclival vein. The trajectory of hypoglossal nerve in HC is mainly from anterosuperior to posteroinferior. The meningeal dura and the arachnoid extended into the HC along the hypoglossal nerve to form the dural and arachnoid sleeves and then fused with the nerve near the extracranial orifice of the HC. CONCLUSIONS: Knowledge of the detailed anatomy of the HC can be helpful in avoiding surgical complications when performing surgery for lesions and the occipital condylar screw placement in this complex area.


Assuntos
Plastinação , Humanos , Osso Occipital/cirurgia , Nervo Hipoglosso/anatomia & histologia , Meninges , Encéfalo
11.
Int J Biol Macromol ; 244: 125236, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37302630

RESUMO

A smart gating membrane based on thermal-sensitive poly (N-isopropyl acrylamide) (PNIPAM)-grafted nanocellulose and carbon nanotube (CNT) was prepared. The presence of PNIPAM shell on cellulose nanofibrils (CNFs) endow the composite membrane with thermal responsiveness. By external stimulation, an increase temperature from 10 °C to 70 °C allows the average pore size of the membrane to be controlled from 28 nm to 110 nm, as well as the water permeance from 440 L·m-2·h-1·bar-1 to 1088 L·m-2·h-1·bar-1. The gating ratio of the membrane can reach 2.47. The photothermal effect of CNT rapidly warms up the membrane to the lowest critical solution temperature in the water, avoiding the constraint that the whole water phase cannot be heated throughout the practical use process. The membrane can precisely control the nanoparticles to concentrate at 25.3 nm, 47.7 nm or 102 nm by adjust the temperature. In addition, the water permeance can be restored to 370 L·m-2·h-1·bar-1 by washing the membrane under light. The smart gating membrane has a wide application in substance multi-stage separation and selective separation, and it can realize self-cleaning.


Assuntos
Nanopartículas , Celulose , Temperatura , Temperatura Baixa , Água
12.
Front Vet Sci ; 10: 1175701, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215478

RESUMO

African swine fever is a highly lethal contagious disease of pigs for which there is no vaccine. Its causative agent African swine fever virus (ASFV) is a highly complex enveloped DNA virus encoding more than 150 open reading frames. The antigenicity of ASFV is still unclear at present. In this study, 35 proteins of ASFV were expressed by Escherichia coli, and ELISA was developed for the detection of antibodies against these proteins. p30, p54, and p22 were presented as the major antigens of ASFV, positively reacting with all five clinical ASFV-positive pig sera, and 10 pig sera experimentally infected by ASFV. Five proteins (pB475L, pC129R, pE199L, pE184L, and pK145R) reacted well with ASFV-positive sera. The p30 induced a rapid and strong antibody immune response during ASFV infection. These results will promote the development of subunit vaccines and serum diagnostic methods against ASFV.

13.
Sci Signal ; 16(785): eade8111, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37192300

RESUMO

Bacillus cereus is a Gram-positive bacterium that mainly causes self-limiting emetic or diarrheal illness but can also cause skin infections and bacteremia. Symptoms of B. cereus ingestion depend on the production of various toxins that target the gastric and intestinal epithelia. From a screen of bacterial isolates from human stool samples that compromised intestinal barrier function in mice, we identified a strain of B. cereus that disrupted tight and adherens junctions in the intestinal epithelium. This activity was mediated by the pore-forming exotoxin alveolysin, which increased the production of the membrane-anchored protein CD59 and of cilia- and flagella-associated protein 100 (CFAP100) in intestinal epithelial cells. In vitro, CFAP100 interacted with microtubules and promoted microtubule polymerization. CFAP100 overexpression stabilized microtubules in intestinal epithelial cells, leading to disorganization of the microtubule network and perturbation of tight and adherens junctions. The disruption of cell junctions by alveolysin depended on the increase in CFAP100, which in turn depended on CD59 and the activation of PI3K-AKT signaling. These findings demonstrate that, in addition to forming membrane pores, B. cereus alveolysin can permeabilize the intestinal epithelium by disrupting epithelial cell junctions in a manner that is consistent with intestinal symptoms and may allow the bacteria to escape the intestine and cause systemic infections. Our results suggest the potential value of targeting alveolysin or CFAP100 to prevent B. cereus-associated intestinal diseases and systemic infections.


Assuntos
Bacillus cereus , Cílios , Humanos , Animais , Camundongos , Bacillus cereus/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Mucosa Intestinal , Exotoxinas/metabolismo , Flagelos
14.
Small ; 19(38): e2301472, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37218011

RESUMO

The combination of optical transparency and mechanical strength is a highly desirable attribute of wood-based glazing materials. However, such properties are typically obtained by impregnation of the highly anisotropic wood with index-matching fossil-based polymers. In addition, the presence of hydrophilic cellulose leads to a limited water resistance. Herein, this work reports on an adhesive-free lamination that uses oxidation and densification to produce transparent all-biobased glazes. The latter are produced from multilayered structures, free of adhesives or filling polymers, simultaneously displaying high optical clarity and mechanical strength, in both dry and wet conditions. Specifically, high values of optical transmittance (≈85.4%), clarity (≈20% with low haze) at a thickness of ≈0.3 mm, and highly isotropic mechanical strength and water resistance (wet strength of ≈128.25 MPa) are obtained for insulative glazes exhibiting low thermal conductivity (0.27 W m-1 K-1 , almost four times lower than glass). The proposed strategy results in materials that are systematically tested, with the leading effects of self-adhesion induced by oxidation rationalized by ab initio molecular dynamics simulation. Overall, this work demonstrates wood-derived materials as promising solutions for energy-efficient and sustainable glazing applications.

15.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1510-1517, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-37005838

RESUMO

Chalcone isomerase is a key rate-limiting enzyme in the biosynthesis of flavonoids in higher plants, which determines the production of flavonoids in plants. In this study, RNA was extracted from different parts of Isatis indigotica and reverse-transcribed into cDNA. Specific primers with enzyme restriction sites were designed, and a chalcone isomerase gene was cloned from I. indigotica, named IiCHI. IiCHI was 756 bp in length, containing a complete open reading frame and encoding 251 amino acids. Homology analysis showed that IiCHI was closely related to CHI protein of Arabidopsis thaliana and had typical active sites of chalcone isomerase. Phylogenetic tree analysis showed that IiCHI was classified into type Ⅰ CHI clade. Recombinant prokaryotic expression vector pET28a-IiCHI was constructed and purified to obtain IiCHI recombinant protein. In vitro enzymatic analysis showed that the IiCHI protein could convert naringenin chalcone into naringenin, but could not catalyze the production of liquiritigenin by isoliquiritigenin. The results of real-time quantitative polymerase chain reaction(qPCR) showed that the expression level of IiCHI in the aboveground parts was higher than that in the underground parts and the expression level was the highest in the flowers of the aboveground parts, followed by leaves and stems, and no expression was observed in the roots and rhizomes of the underground parts. This study has confirmed the function of chalcone isomerase in I. indigotica and provided references for the biosynthesis of flavonoid components.


Assuntos
Arabidopsis , Isatis , Isatis/genética , Proteínas de Plantas/metabolismo , Filogenia , Arabidopsis/genética , Flavonoides , Clonagem Molecular
16.
Int J Public Health ; 68: 1605572, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36938299

RESUMO

Objectives: The purpose of this study was to explore the association between multiple chronic conditions (MCCs) and depressive symptoms among older adults in China. Methods: We used the fourth round of data from the China Health and Retirement Longitudinal Study, and included 9789 older adults aged 60 years old and above. Results: Compared with the older adults without chronic disease, older adults with MCCs and those with one chronic disease had a high risk of depression (MCCs: OR-adjusted: 1.55, 95% CI: 1.37 to 1.75; one chronic disease: OR-adjusted: 1.20, 95% CI: 1.05-1.37). In urban areas, the prevalence among older adults with MCCs was 2.01 times higher than that among older adults without chronic disease (OR-adjusted: 2.01, 95% CI: 1.56-2.60), while it was 1.44 times higher in rural areas (OR-adjusted:1.44, 95% CI: 1.25-1.65). Self-reported health, duration of sleep, social activities, and type of medical insurance were the influencing factors of depressive symptoms in older adults. Conclusion: This study contributed to enriching the research on the relationship between MCCs and depressive symptoms in older adults in China.


Assuntos
Múltiplas Afecções Crônicas , Aposentadoria , Humanos , Idoso , Pessoa de Meia-Idade , Depressão/epidemiologia , Estudos Longitudinais , Doença Crônica , China/epidemiologia
17.
Int J Biol Macromol ; 235: 123884, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36870642

RESUMO

Currently, cellulose-based aerogel materials are a hot topic owing to their high specific surface area and high porosity, as well as the green, degradable and biocompatible characteristics of cellulosic materials. Modification of cellulose to enhance the adsorption properties of cellulose-based aerogels has important research significance in solving the problem of water body pollution. In this paper, cellulose nanofibers (CNFs) were modified with polyethyleneimine (PEI), and modified aerogels with directional structures were prepared by a simple reaction and freeze-drying method. The adsorption behavior of the aerogel followed the adsorption kinetic models and isotherm models. More significantly, the aerogel could rapidly adsorb microplastics, reaching equilibrium within 20 min. Furthermore, the fluorescence displayed directly expresses the occurrence of the adsorption behavior of the aerogels. Therefore, the modified cellulose nanofiber aerogels were of reference significance for microplastic removal from water bodies.


Assuntos
Nanofibras , Nanofibras/química , Microplásticos , Plásticos , Polietilenoimina , Água/química , Adsorção , Celulose/química
18.
J Hazard Mater ; 441: 129965, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36122524

RESUMO

Oil spills frequently occur in the ocean, and adsorption is one of the effective ways to deal with oil spills. Compared with other adsorbent materials, biomass aerogel has superior selective adsorption capacity. CNF/SA aerogels with good mechanical properties (340 kPa at 90 % strain) and high adsorption capacity (88.91 g/g) were prepared by mixing cellulose nanofibers (CNF) with sodium alginate (SA) through bidirectional freeze-drying, ionic crosslinking, and surface modification to effectively solve the ocean oil spill problem. The bidirectional freeze-drying technology is a green and efficient technique for preparing layered microstructured composite aerogels. The prepared aerogels have a three-dimensional interpenetrating lamellar structure, low density (24.2 mg/cm3), high porosity (97.85 %), and high hydrophobicity (WCA = 144.5°), can be calibrated and used repeatedly. It has potential applications in water-oil separation and can be used as an absorbent for effectively treating oil spills in the ocean environment.


Assuntos
Incrustação Biológica , Nanofibras , Alginatos , Incrustação Biológica/prevenção & controle , Celulose/química , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Nanofibras/química , Oceanos e Mares , Água/química
19.
Int J Biol Macromol ; 225: 79-89, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36460246

RESUMO

Anisotropic hydrogels have attracted extensive attention because they are similar to natural hydrogel-like materials and exhibit superiority and new functions that isotropic hydrogels cannot. Here, we fabricated strong and tough carboxymethyl cellulose-based conductive hydrogels with oriented hierarchical structures through pre-stretching, solvent displacement induced phase separation, and subsequent ionic crosslinking immobilization. Solvent displacement made the pre-stretched carboxymethyl cellulose-based polymer network more dense and linear, while the toughness of the hydrogel was further improved under the effect of phase separation. Strong and tough hydrogels were prepared by combining pre-stretching and phase separation; the variation range (tensile strength of 2.24-6.19 MPa and toughness of 19.41-22.92 MJ/m3) can be adjusted by the stretching ratio. Compared with traditional carboxymethyl cellulose-based hydrogels, the tensile strength and toughness were increased by 49 times and 15 times, respectively. In addition, the hydrogels had good underwater stability, ion cross-linking made the hydrogels have good conductivity, and the directional stratification structure gave the hydrogels conductive anisotropy. These characteristics give hydrogel sensors broad application prospects in flexible wearable devices, anisotropic sensors, and intelligent underwater devices.


Assuntos
Carboximetilcelulose Sódica , Hidrogéis , Anisotropia , Condutividade Elétrica , Solventes
20.
Neuron ; 110(23): 3936-3951.e10, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36174572

RESUMO

Zika virus (ZIKV) can infect human developing brain (HDB) progenitors resulting in epidemic microcephaly, whereas analogous cellular tropism offers treatment potential for the adult brain cancer, glioblastoma (GBM). We compared productive ZIKV infection in HDB and GBM primary tissue explants that both contain SOX2+ neural progenitors. Strikingly, although the HDB proved uniformly vulnerable to ZIKV infection, GBM was more refractory, and this correlated with an innate immune expression signature. Indeed, GBM-derived CD11b+ microglia/macrophages were necessary and sufficient to protect progenitors against ZIKV infection in a non-cell autonomous manner. Using SOX2+ GBM cell lines, we found that CD11b+-conditioned medium containing type 1 interferon beta (IFNß) promoted progenitor resistance to ZIKV, whereas inhibition of JAK1/2 signaling restored productive infection. Additionally, CD11b+ conditioned medium, and IFNß treatment rendered HDB progenitor lines and explants refractory to ZIKV. These findings provide insight into neuroprotection for HDB progenitors as well as enhanced GBM oncolytic therapies.


Assuntos
Infecção por Zika virus , Zika virus , Humanos , Células Mieloides , Células-Tronco , Interferons
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