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1.
J Hazard Mater ; 382: 120993, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31465944

RESUMO

Polyimide-modified carbon nanotubes (PI/CNTs) were synthesized via a solvent-free thermal method and used as a metal-free catalyst to activate peroxymonosulfate for organic contaminant degradation without light irradiation. The characterization results suggested that PI was loaded onto the surface of CNTs. The catalytic ability of the PI/CNTs was strongly correlated with the content of PI in the catalysts. The PI/CNTs (22% of PI) showed the highest catalytic efficiency for organic pollutant degradation at room temperature. The degradation efficiency of acid orange 7 (AO7) dye was significantly enhanced to 98.9% within 15 min, compared to the efficiency of 2.2% exhibited by pure PI. The radical quenching tests and electron paramagnetic resonance spectrometry proved that singlet oxygen, instead of hydroxyl radicals or sulfate radicals, played a dominant role during the catalytic oxidation of AO7. The influences of operation parameters including temperature and catalyst amount were investigated. The PI/CNTs metal-free catalyst exhibited high catalytic activity under a broad range of pH values. The recycling study of four repeated reactions demonstrated good stability of the PI/CNTs. This work provided a promising metal-free catalyst for degradation of organic pollutants in aqueous solutions, contributing to the development of green materials for sustainable remediation.

2.
Nanoscale ; 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31524919

RESUMO

Flexible wearable and implantable piezoresistive sensors have attracted lots of attention in the applications of healthcare monitoring, disease diagnostics, and human-machine interactions. However, the restricted sensing range, low sensing sensitivity at small strains, limited mechanical stability at high strains, and sophisticated fabrication processes restrict the far-reaching applications of these sensors for ultrasensitive full-range healthcare monitoring. In this work, an implantable and versatile piezoresistive sensor was developed from a series of conductive composites. The conductive composites, hydroxyethyl cellulose (HEC)/soy protein isolate (SPI)/polyaniline (PANI) sponges (HSPSs), were prepared by lyophilization of HEC/SPI solution and then in situ polymerization of aniline. The sensitivity, response time, and mechanical robustness of the HSPS sensors were characterized, and they can achieve a gauge factor of -0.29, a response time of 0.14 s, and sensing stability for at least 100 cycles. The HSPS sensors could efficiently work in vivo for 4 weeks for the measurement of stimuli, without severe inflammatory reaction. When the versatile HSPS sensors were attached to different parts of the human body, they could detect a variety of human motions including coughing, bending of fingers and elbow, abdominal breathing and walking. Notably, the HSPS sensors could be used to monitor the nerve repair in rats and the results are highly consistent with the electrophysiological data. At the same time a new score system was developed to evaluate rat nerve repair. These results indicate that the HSPS sensors exhibit good biocompatibility, sensitivity, sensing stability and fast response time. The HSPS sensors can be used not only as implantable sensors in vivo but also for analyzing human body motions. Furthermore, they provide an effective sensor device and a real-time, dynamic method for evaluating nerve repair without damage and death of animals. Hence, HSPSs might have great potential in in vivo detection, monitoring of human-machine interfacing interactions and the nerve tissue engineering field.

3.
BMC Pharmacol Toxicol ; 20(1): 56, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31500666

RESUMO

BACKGROUND: There are evidences that chlorogenic acid (CGA) has antidepressant effects, however the underlying molecular mechanism has not been well understood. The aim of the study was to explore the neuroprotective effect of CGA on corticosterone (CORT)-induced PC 12 cells and its mechanism, especially the autophagy pathway. METHODS: PC12 cells were incubated with CORT (0, 100, 200, 400 or 800 µM) for 24 h, cell viability was measured by MTT assay. PC12 cells were cultured with 400 µM of CORT in the absence or presence of CGA (25 µg/ml) for 24 h, morphologies and specific marker of autophagosome were observed by transmission electron microscope (TEM) and confocal immunofluorescence microscopy, respectively. In addition, PC12 cells were treated with different doses of CGA (0, 6.25, 12.5, 25 or 50 µg/ml) with or without CORT (400 µM) for 24 h, cell viability and changes in the morphology were observed, and further analysis of apoptotic and autophagic proteins, and expression of AKT/mTOR signaling pathway were carried out by Western blot. Specific inhibitors of autophagy 3-Methyladenine (3-MA) and chloroquine (CQ) were added to the PC12 cells cultures to explore the potential role of autophagy in CORT-induced neuronal cell apoptosis. RESULTS: Besides decreasing PC12 cell activity, CORT could also induce autophagy and apoptosis of PC12 cells, while CGA could reverse these effects. In addition, CGA treatment regulated AKT/mTOR signaling pathway in PC12 cells. CGA, similar to 3-MA and QC, significantly inhibited CORT-induced apoptosis in PC12 cells. CONCLUSIONS: Our results provide a new molecular mechanism for the treatment of CORT-induced neurotoxicity by CGA, and suggest CGA may be a potential substance which is can alleviate depression.

4.
Brain Res ; 1723: 146379, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31415766

RESUMO

Abnormal accumulation of amyloid-ß (Aß) peptide defines progression of Alzheimer's disease (AD) pathology in brain. Here, we investigated expressive changes of two main Aß transport receptors low-density lipoprotein receptor related protein-1 (LRP1) and receptor for advanced glycation end products (RAGE) in a novel AD mice (APP23) with chronic cerebral hypoperfusion (CCH) model, moreover, examined a protective effect of a free radical scavenger edaravone (Eda). In contrast to wild type (WT) and APP23 mice, CCH strongly accelerated abnormal Aß40 depositions and cerebral amyloid angiopathy (CAA) pathology, increased both LRP1 and RAGE expressions in brain parenchyma, while a decrease of LRP1 and an increase of RAGE were observed in vascular endothelial cells at age 12 months (M) of AD mice. Furthermore, CCH strongly increased expressions of two hypoxia-related proteins hypoxia inducible factor-1α (HIF-1α) and heme oxygenase-1 (HO-1), two oxidative-related proteins 4-hydroxy-2-nonenal (4-HNE) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), and decreased both two vital nutrient transporter proteins major facilitator super family domain containing 2a (Mfsd2a) and glucose transporter 1 (Glut1) expressions. Such the above abnormal pathological changes were significantly ameliorated by edaravone treatment. The present study demonstrated that CCH strongly enhanced primary AD pathology causing double imbalances of Aß efflux and influx transport related proteins in the cortical blood vessels in AD mice, and that such a neuropathologic abnormality was greatly ameliorated by Eda.

5.
ACS Appl Mater Interfaces ; 11(38): 34766-34776, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31429547

RESUMO

The construction of polymeric nanocomponents into a hierarchical structure poses great importance for subsequent biomedical applications. Herein, we report for the first time the electroassembly of chitin nanoparticles (14 nm ± 3 nm from transmission electron microscopy) to construct thick and freestanding hydrogels, which can be further dried to obtain high porous and tough aerogels for wound healing. The electroassembly is a simple, straightforward, and controllable process, which crucially depends on the pH of the chitin nanoparticle suspension and the degree of deacetylation of chitin. Interestingly, the electroassembly of chitin nanoparticles is completely reversible, suggesting the physical assembly feature of the freestanding hydrogel. By using supercritical CO2 drying and freeze-drying, chitin aerogels and cryogels can be facilely obtained. Because of the intriguing features (i.e., large surface area, interconnected porous structure, and enhanced hydrophilicity), chitin aerogels demonstrate adorable performance to accelerate the healing of wounds.

6.
J Stroke Cerebrovasc Dis ; 28(10): 104310, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31383622

RESUMO

BACKGROUND: The pathological impact of chronic cerebral hypoperfusion (CCH) on Alzheimer's disease (AD) is still poorly understood. In the present study, we investigated the role of CCH on an AD mouse model in phosphorylated tau and α-synuclein pathology, neurovascular unit, cerebrovascular remodeling, and neurovascular trophic coupling. Moreover, examined protective effect of a new antioxidant Twendee X (TwX). METHODS: APP23 mice were implanted to bilateral common carotid arteries stenosis with ameroid constrictors to gradually decrease the cerebral blood flow. The effects of the administration of TwX were evaluated by immunohistochemical analysis and Immunofluorescent histochemistry. RESULTS: The present study revealed that the expressions of phospho-tau and phospho-α-synuclein were significantly increased in the APP23 + CCH mice group as compared with wild type and APP23 mice groups (*P < .05 and ⁎⁎P < .01 versus WT; #P < .05 and ##P < .01 versus APP23). In addition, CCH significantly exacerbated MMP-9 activation relating to blood-brain barrier destruction (⁎⁎P < .01 versus WT; #P < .05, and ##P < .01 versus APP23), enhanced neurovascular remodeling, and impaired a neurovascular trophic coupling in the vascular endothelial BDNF expression of the APP23 + CCH group. TwX treatment (20 mg/kg/day, from 4.5 to 12 months) significantly reduced tau and α-synuclein pathologies, ameliorated neurovascular dysfunction compared with APP23 + CCH group. CONCLUSIONS: Our findings indicate that administration of a new antioxidative mixture TwX substantially reduced the above neuropathologic abnormalities, suggesting a potential therapeutic benefit of TwX for AD with CCH.

7.
Int J Biol Macromol ; 139: 191-198, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31374279

RESUMO

The research and development of environmentally friendly and nontoxic biomass products has become an important topic of worldwide concern. In this study, natural materials were used for producing a kind of antibacterial mats. Cellulose acetate (CA) mats prepared by electrospinning technology were converted to cellulose mats via alkali hydrolysis. Chitosan (CS) and tannic acid (TA) were used to fabricate the composite mats by using layer-by-layer (LBL) self-assembly technology. The cellulose mats exhibited good fibrous structure, three-dimensional network and small average fiber diameter ranging from 300 to 400 nm. Besides, the results of mechanical properties testing and water contact angle measurements of these LBL-structured mats demonstrated that the LBL technology was able to improve their surface characteristics, hydrophilicity and mechanical properties. The analysis of antibacterial activity of the mats revealed over 86% antibacterial activity against Escherichia coli and up to 99% antibacterial activity against Staphylococcus aureus. Hence, the LBL-structured cellulose mats have excellent antibacterial activity and mechanical properties. Therefore, these nano-cellulose mats can be expected to have considerable development prospects for food packaging or wound dressing.

8.
J Mater Chem B ; 7(33): 5096-5103, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31432879

RESUMO

Excessive bleeding due to trauma, surgery and diseases may cause severe mortalities. Here, an emerging chitin nanogel/rectorite nanocomposite is developed for effective hemorrhage control. Chitin chains are intercalated into rectorite and subsequent mechanical high speed stirring generates chitin nanogels, which assemble on the surface of the rectorite nanoplates through electrostatic interactions to form a sandwich structure. The in vitro experiments reveal that the nanocomposite exhibits favorable biocompatibility and negligible hemolysis (<3.5%) as compared to rectorite (40%). The nanocomposite stops bleeding in 121 s in rat tail incision and exhibits higher hemostatic activity in the rabbit artery injury model as compared to a commercialized chitosan hemostat, Celox. The efficient blood clotting activity is attributed to the induction of a coagulation cascade by rectorite and the quick adsorption and aggregation of platelets and red blood cells by chitin. The enhanced biocompatibility and hemostatic activity of the chitin/rectorite nanocomposite make it a safe and cost effective hemostat to control bleeding.

9.
Neuroscience ; 416: 126-136, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394196

RESUMO

Alzheimer's disease (AD) in the elderly is frequently accompanied by chronic cerebral hypoperfusion (CCH), which impairs the clearance of amyloid beta (Aß) due to the dysfunction of the blood-brain barrier (BBB) and accelerates the AD pathology. Since the coagulation and complement cascades are associated with BBB dysfunction and AD pathology, we investigated the expression changes of coagulation (fibrinogen alpha chain-FGA, coagulation factor XIII A chain-Factor XIIIα) and complement (plasma protease C1 inhibitor-C1-INH, Complement component 3-C3) factors in the brain of novel AD model (APP23) mice with CCH at 12 months of age. Immunohistochemical and immunofluorescent analysis showed that the expressions of FGA, Factor XIIIα, C1-INH and C3 were significantly increased in cerebral neocortex, hippocampus, and thalamus of APP23 + CCH group (n = 12) as compared with wild type (WT, n = 10) and APP23 (n = 10) groups (⁎P < .05 and ⁎⁎P < .01 vs WT; #P < .05 and ##P < .01 vs APP23), especially near and inside of neurovascular unit. The present study suggests that CCH activated both the coagulation and complement cascades in a novel AD model mice brain accompanied by the acceleration of AD pathology.

10.
J Alzheimers Dis ; 71(1): 327-339, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31403949

RESUMO

Alzheimer's disease (AD) and chronic cerebral hypoperfusion (CCH) often coexist in dementia patients in aging societies. The hallmarks of AD including amyloid-ß (Aß)/phosphorylated tau (pTau) and pathology-related events such as neural oxidative stress and neuroinflammation play critical roles in pathogenesis of AD with CCH. A large number of lessons from failures of drugs targeting a single target or pathway on this so complicated disease indicate that disease-modifying therapies targeting multiple key pathways hold potent potential in therapy of the disease. In the present study, we used a novel mouse model of AD with CCH to investigate a potential therapeutic effect of a free radical scavenger, Edaravone (EDA) on AD with CCH via examining motor and cognitive capacity, AD hallmarks, neural oxidative stress, and neuroinflammation. Compared with AD with CCH mice at 12 months of age, EDA significantly improved motor and cognitive deficits, attenuated neuronal loss, reduced Aß/pTau accumulation, and alleviated neural oxidative stress and neuroinflammation. These findings suggest that EDA possesses clinical and pathological benefits for AD with CCH in the present mouse model and has a potential as a therapeutic agent for AD with CCH via targeting multiple key pathways of the disease pathogenesis.

11.
Neuroscience ; 415: 31-43, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31344397

RESUMO

Hypoxia inducible factor-1α (HIF-1α) is a key transcription factor that maintains oxygen homeostasis. Hypoxic stress is related to the pathogenesis of amyotrophic lateral sclerosis (ALS), and impaired HIF-1α induces motor neuron degeneration in ALS. Dimethyloxalylglycine (DMOG) upregulates the stability of HIF-1α expression and shows neuroprotective effects, but has not been used in ALS as an anti-hypoxic stress treatment. In the present study, we investigated hypoxic stress in ALS model mice bearing G93A-human Cu/Zn superoxide dismutase by in vivo HIF-1α imaging, and treated the ALS mice with DMOG. In vivo HIF-1α imaging analysis showed enhanced hypoxic stress in both the spinal cord and muscles of lower limbs of ALS mice, even at the pre-symptomatic stage. HIF-1α expression decreased as the disease progressed until 126 days of age. DMOG treatment significantly ameliorated the decrease in HIF-1α expression, the degeneration of both spinal motor neurons and myofibers in lower limbs, gliosis and apoptosis in the spinal cord. This was accompanied by prolonged survival. The present study suggests that in vivo bioluminescence resonance energy transfer (BRET) HIF-1α imaging is useful for evaluating hypoxic stress in ALS, and that the enhancement of HIF-1α is a therapeutic target for ALS patients.

12.
BMC Plant Biol ; 19(1): 232, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159725

RESUMO

BACKGROUND: Compared with white-fleshed sweetpotato (WFSP), purple-fleshed sweetpotato (PFSP) is a desirable resource for functional food development because of the abundant anthocyanin accumulation in its tuberous roots. Some studies have shown that the expression regulation mediated by miRNA plays an important role in anthocyanin biosynthesis in plants. However, few miRNAs and their corresponding functions related to anthocyanin biosynthesis in tuberous roots of sweetpotato have been known. RESULTS: In this study, small RNA (sRNA) and degradome libraries from the tuberous roots of WFSP (Xushu-18) and PFSP (Xuzishu-3) were constructed, respectively. Totally, 191 known and 33 novel miRNAs were identified by sRNA sequencing, and 180 target genes cleaved by 115 known ib-miRNAs and 5 novel ib-miRNAs were identified by degradome sequencing. Of these, 121 miRNAs were differently expressed between Xushu-18 and Xuzishu-3. Integrated analysis of sRNA, degradome sequencing, GO, KEGG and qRT-PCR revealed that 26 differentially expressed miRNAs and 36 corresponding targets were potentially involved in the anthocyanin biosynthesis. Of which, an inverse correlation between the expression of ib-miR156 and its target ibSPL in WFSP and PFSP was revealed by both qRT-PCR and sRNA sequencing. Subsequently, ib-miR156 was over-expressed in Arabidopsis. Interestingly, the ib-miR156 over-expressing plants showed suppressed abundance of SPL and a purplish phenotype. Concomitantly, upregulated expression of four anthocyanin pathway genes was detected in transgenic Arabidopsis plants. Finally, a putative ib-miRNA-target model involved in anthocyanin biosynthesis in sweetpotato was proposed. CONCLUSIONS: The results represented a comprehensive expression profiling of miRNAs related to anthocyanin accumulation in sweetpotato and provided important clues for understanding the regulatory network of anthocyanin biosynthesis mediated by miRNA in tuberous crops.


Assuntos
Antocianinas/biossíntese , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/genética , MicroRNAs/genética , RNA de Plantas/genética , Antocianinas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Ipomoea batatas/metabolismo , MicroRNAs/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , RNA de Plantas/metabolismo , Análise de Sequência de RNA
13.
ACS Nano ; 13(6): 6372-6382, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31184474

RESUMO

The regeneration of bone tissue is regulated by both osteogenic and angiogenic growth factors which are expressed in a coordinated cascade of events. The aim of this study was to create a dual growth factor-release system that allows for time-controlled release to facilitate bone regeneration. We fabricated core-shell SF/PCL/PVA nanofibrous mats using coaxial electrospinning and layer-by-layer (LBL) techniques, where bone morphogenetic protein 2 (BMP2) was incorporated into the core of the nanofibers and connective tissue growth factor (CTGF) was attached onto the surface. Our study confirmed the sustained release of BMP2 and a rapid release of CTGF. Both in vitro and in vivo experiments demonstrated improvements in bone tissue recovery with the dual-drug release system. In vivo studies showed improvement in bone regeneration by 43% compared with single BMP2 release systems. Time-controlled release enabled by the core-shell nanofiber assembly provides a promising strategy to facilitate bone healing.

14.
J Stroke Cerebrovasc Dis ; 28(7): 1993-2002, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31029568

RESUMO

BACKGROUND: Multiple pathogeneses are involved in Alzheimer's disease (AD), such as amyloid-ß accumulation, neuroinflammation, and oxidative stress. The pathological impact of chronic cerebral hypoperfusion on Alzheimer's disease is still poorly understood. METHODS: APP23 mice were implanted to bilateral common carotid arteries stenosis with ameroid constrictors for slowly progressive chronic cerebral hypoperfusion (CCH). The effects of the administration of Twendee X (TwX) were evaluated by behavioral analysis, immunohistochemical analysis, and immunofluorescent histochemistry. RESULTS: In the present study, chronic cerebral hypoperfusion, which is commonly found in aged Alzheimer's disease, significantly exacerbated motor dysfunction of APP23 mice from 5 months and cognitive deficit from 8 months of age, as well as neuronal loss, extracellular amyloid-ß plaque and intracellular oligomer formations, and amyloid angiopathy at 12 months. Severe upregulations of oxidative markers and inflammatory markers were found in the cerebral cortex, hippocampus, and thalamus at 12 months. Twendee X treatment (20 mg/kg/d, from 4.5 to 12 months) substantially rescued the cognitive deficit and reduced the above amyloid-ß pathology and neuronal loss, alleviated neuroinflammation and oxidative stress. CONCLUSIONS: The present findings suggested a potential therapeutic benefit of Twendee X for Alzheimer's disease with chronic cerebral hypoperfusion.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Ácido Ascórbico/administração & dosagem , Encéfalo/efeitos dos fármacos , Transtornos Cerebrovasculares/tratamento farmacológico , Cistina/administração & dosagem , Glutamina/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Ácido Ascórbico/farmacologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Circulação Cerebrovascular/efeitos dos fármacos , Transtornos Cerebrovasculares/patologia , Transtornos Cerebrovasculares/fisiopatologia , Doença Crônica , Cognição/efeitos dos fármacos , Cistina/farmacologia , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Glutamina/farmacologia , Mediadores da Inflamação/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Mutação , Estresse Oxidativo/efeitos dos fármacos , Placa Amiloide
15.
Biomater Sci ; 7(6): 2571-2581, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30977470

RESUMO

Traumatic injury is a major cause of mortality, and poor wound healing affects millions of people. Thus, the development of effective wound dressings is essential for speeding up wound healing and decreasing mortality. In this study, a suspension of carboxylated brown algae cellulose nanofibers (BACNFs) with a high aspect ratio was freeze dried to prepare a sponge. The sponge showed high porosity and water absorption capacity; thus, it can absorb wound exudates when used as a wound dressing. In addition, quaternized ß-chitin (QC) with antibacterial properties was intercalated into the interlayer space of the organic rectorite (OREC) via electrostatic interactions to obtain composite suspensions (QCRs) with improved antimicrobial activity compared to that of QC alone. Subsequently, the BACNF sponge was soaked in the QCR suspension to absorb QCRs via electrostatic interactions and hydrogen bonding from which cellulose nanofiber/quaternized chitin/organic rectorite composite (BACNF/QCR) sponges were constructed via freeze-drying. The in vivo animal tests demonstrated that the BACNF/QCR sponges rapidly induced hemostasis in a rat tail amputation test, making them superior to the traditional hemostatic materials. Furthermore, BACNFs/QCRs could substantially promote collagen synthesis and neovascularization, thereby accelerating wound healing 3 days earlier than gauze. This multi-functional biomedical material, fabricated using natural substances, shows great potential to be used for wound healing.

16.
J Alzheimers Dis ; 68(4): 1667-1675, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30958362

RESUMO

Alzheimer's disease (AD) is the most common dementia and a progressive neurodegenerative disorder aggravated by chronic hypoperfusion (HP). Since numerous evidence suggests that inflammation is related with AD pathology, we investigated the expression change of two anti-inflammatory markers, inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4) and alpha-2-HS-glycoprotein (AHSG), in a novel AD model (APP23) with HP at 12 month of age. As compared with wild type (WT, n = 10), immunohistochemical analysis showed a higher ITIH4 and a lower AHSG expressions in the cerebral cortex, hippocampus, and thalamus of the APP23 + HP group (n = 12) than the simple APP23 (n = 10) group (*p < 0.05 and **p < 0.01 versus WT; #p < 0.05 and # #p < 0.01 versus APP23). The present study provides an upregulation of anti-inflammatory ITIH4 and a downregulation of pro-inflammatory TNFα-dependent AHSG in a novel AD plus HP mice model.

17.
Carbohydr Polym ; 213: 329-337, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30879676

RESUMO

Natural-based nanocomposites are competitive and promising materials for biomedical applications due to their biocompatibility. Herein, a novel natural-based composite was fabricated by alternately depositing lysozyme (LY) and albumin egg (AE) on electrospun cellulose nanofibrous mats via layer-by-layer self-assembly (LBL) technology. To indicate the successful deposition process and investigate the variations of the mats during LBL process, the surface morphology, physical property, chemical composition, wetting behavior and thermal stability were systematically studied. The results showed that the surface morphology and composition of the mats were significantly influenced by LBL process, which further resulted in the variation of wetting behavior. Besides, the mechanical properties were enhanced after LBL modification. In addition, the LBL structured nanofibrous mats exhibited antibacterial activity and excellent biocompatibility with L929 fibroblasts. In brief, LY and AE coated LBL structured cellulose nanofibrous mats, especially the 15 bilayers coated mats, have considerably potential applications in the biomedical field.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Celulose/química , Proteínas do Ovo/química , Escherichia coli/efeitos dos fármacos , Nanofibras/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Ovos/análise , Fibroblastos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Propriedades de Superfície
18.
J Hazard Mater ; 371: 165-174, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-30849571

RESUMO

Oily wastewater is a worldwide problem threatening the environment and humans. High flux and low-energy consumption separation of oil and water is urgently required but still faces great challenges. In this study, nanofibrous membranes with superhydrophilic and underwater superoleophobic surfaces were fabricated by grafting acrylic acid onto plasma-treated electrospun polystyrene/polyacrylonitrile (PS/PAN) membranes. The morphologies, chemical compositions, mechanical and surface properties of the membranes were examined in detail. The water contact angles of the PS/PAN membranes were 137.4°, 130.1°, 119.5°, 88.1° and 80.2°, respectively, which decreased to 76.5°, 47.9°, 34.4°, 0° and 0° after grafting treatment, proving that the modification improved the surface hydrophilicity of the membranes due to the introduction of hydrophilic groups. In addition, a gravity-driven filtration device was utilized to investigate the oil/water separation potential of the membranes. The results indicated that the grafted PS/PAN membranes separated the layered oil/water mixtures with permeate flux up to 57509 L m-2 h-1, while high fluxes of 1390-6460 L m-2 h-1 for the separation of different oil-in-water emulsions. Importantly, the membranes still maintained high flux and efficiency even after several cycles of separation. Therefore, the reusable membranes can be expected to be potential cost-effective materials for oil/water treatment.

19.
Biofabrication ; 11(3): 032002, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30759423

RESUMO

While conventional material fabrication methods focus on form and strength to achieve function, the fabrication of material systems for emerging life science applications will need to satisfy a more subtle set of requirements. A common goal for biofabrication is to recapitulate complex biological contexts (e.g. tissue) for applications that range from animal-on-a-chip to regenerative medicine. In these cases, the material systems will need to: (i) present appropriate surface functionalities over a hierarchy of length scales (e.g. molecular features that enable cell adhesion and topographical features that guide differentiation); (ii) provide a suite of mechanobiological cues that promote the emergence of native-like tissue form and function; and (iii) organize structure to control cellular ingress and molecular transport, to enable the development of an interconnected cellular community that is engaged in cell signaling. And these requirements are not likely to be static but will vary over time and space, which will require capabilities of the material systems to dynamically respond, adapt, heal and reconfigure. Here, we review recent advances in the use of electrically based fabrication methods to build material systems from biological macromolecules (e.g. chitosan, alginate, collagen and silk). Electrical signals are especially convenient for fabrication because they can be controllably imposed to promote the electrophoresis, alignment, self-assembly and functionalization of macromolecules to generate hierarchically organized material systems. Importantly, this electrically based fabrication with biologically derived materials (i.e. electrobiofabrication) is complementary to existing methods (photolithographic and printing), and enables access to the biotechnology toolbox (e.g. enzymatic-assembly and protein engineering, and gene expression) to offer exquisite control of structure and function. We envision that electrobiofabrication will emerge as an important platform technology for organizing soft matter into dynamic material systems that mimic biology's complexity of structure and versatility of function.

20.
Carbohydr Polym ; 210: 9-16, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30732785

RESUMO

Novel antimicrobials with well biocompatibility are urgently needed for human public health protecting. Here, the silk fibroin (SF) nanofibrous mats coated with carboxymethyl chitosan (CMC), both extracted from natural polymers, were fabricated by combining electrospinning and electrostatic layer-by-layer (LBL) self-assembly techniques. The amphoteric CMC could be easily adsorbed on the surface of SF nanofibers due to the electrostatic interaction, which were a highly efficient and "green" route for the surface modification of SF mats. The mats after LBL procedure exhibited better hydrophilicity and stronger mechanical properties. The experimental results demonstrated that the LBL modified mats not only kept well biocompatibility but also obtained extremely enhanced antibacterial activity. More importantly, the mats displayed better bacterial inhibition with the increased CMC layers. LBL10 and LBL10.5 owned the antibacterial activity of more than 67% at the bacterial concentrations of 106 cfu ml-1 after 24 h cultivation, which implied that these novel natural polymer-based materials could be utilized as wound dressings for clinical skin and tissue regeneration, especially for infected wounds.

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