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Flexible supercapacitors can potentially power next-generation flexible electronics. However, the mechanical and electrochemical stability of flexible supercapacitors under different flexible conditions is limited by the weak bonding between adjacent layers, posing a significant hindrance to their practical applicability. Herein, based on the uninterrupted 3D network during the growth of bacterial cellulose (BC), a flexible all-in-one supercapacitor is cultivated through a continuous biosynthesis process. This strategy ensures the continuity of the 3D network of BC throughout the material, thereby forming a continuous electrode-separator-electrode structure. Benefitting from this bioinspired structure, the all-in-one supercapacitor not only achieves a high areal capacitance (3.79 F cm-2) of electrodes but also demonstrates the integration of high tensile strength (2.15 MPa), high shear strength (more than 54.6 kPa), and high bending resistance, indicating a novel pathway toward high-performance flexible power sources.
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Cellulose nanofiber (CNF) possesses excellent intrinsic properties, and many CNF-based high-performance structural and functional materials have been developed recently. However, the coordination of the mechanical properties and functionality is still a considerable challenge. Here, a CNF-based structural material is developed by a bioinspired gradient structure design using hollow magnetite nanoparticles and the phosphorylation-modified CNF as building blocks, which simultaneously achieves a superior mechanical performance and electromagnetic wave absorption (EMA) ability. Benefiting from the gradient design, the flexural strength of the structural material reached â¼205 MPa. Meanwhile, gradient design improves impedance matching, contributing to the high EMA ability (-59.5 dB) and wide effective absorption width (5.20 GHz). Besides, a low coefficient of thermal expansion and stable storage modulus was demonstrated as the temperature changes. The excellent mechanical, thermal, and EMA performance exhibited great potential for application in stealth equipment and electromagnetic interference protecting electronic packaging materials.
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The exploration of extreme environments has become necessary for understanding and changing nature. However, the development of functional materials suitable for extreme conditions is still insufficient. Herein, a kind of nacre-inspired bacterial cellulose (BC)/synthetic mica (S-Mica) nanopaper with excellent mechanical and electrical insulating properties that has excellent tolerance to extreme conditions is reported. Benefited from the nacre-inspired structure and the 3D network of BC, the nanopaper exhibits excellent mechanical properties, including high tensile strength (375 MPa), outstanding foldability, and bending fatigue resistance. In addition, S-Mica arranged in layers endows the nanopaper with remarkable dielectric strength (145.7 kV mm-1 ) and ultralong corona resistance life. Moreover, the nanopaper is highly resistant to alternating high and low temperatures, UV light, and atomic oxygen, making it an ideal candidate for extreme environment-resistant materials.
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The oriented pore structure of wood endows it with a variety of outstanding properties, among which the low thermal conductivity has attracted researchers to develop wood-like aerogels as excellent thermal insulation materials. However, the increasing demands of environmental protection have put forward new and strict requirements for the sustainability of aerogels. Here, we report an all-natural wood-inspired aerogel consisting of all-natural ingredients and develop a method to activate the surface-inert wood particles to construct the aerogel. The obtained wood-inspired aerogel has channel structure similar to that of natural wood, endowing it with superior thermal insulation properties to most existing commercial sponges. In addition, remarkable fire retardancy and complete biodegradability are integrated. With the above outstanding performances, this sustainable wood-inspired aerogel will be an ideal substitute for the existing commercial thermal insulation materials.
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Widely used disposable plastic tableware is usually buried or directly discharged into the natural environment after using, which poses potential threats to the natural environment and human health. To solve this problem, nondegradable plastic tableware needs to be replaced by tableware composed of biodegradable structural materials with both food safety and the excellent mechanical and thermal properties. Here, a food-safe sargassum cellulose nanofiber (SCNF) is extracted from common seaweed in an efficient and low energy consuming way under mild reaction conditions. Then, by assembling the SCNF into a dense bulk material, a strong sargassum cellulose nanofiber structural material (SCNSM) with high strength (283 MPa) and high thermal stability (>160 °C) can be prepared. The SCNSM also possesses good machinability, which can be processed into tableware with different shapes, e.g., knives and forks. The overall performance of the SCNSM-based tableware is better than commercial plastic, wood-based, and poly(lactic acid) tableware, which shows great application potential in the tableware field.
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Alimentos , Nanofibras , Humanos , Celulose/química , Nanofibras/químicaRESUMO
Flavonoids, alkaloids, glucosides and tannins with good corrosion inhibition are the main natural components in plants. In this work, procyanidin B2 (PCB2), a natural flavonoid, was firstly isolated from Uncaria laevigata. Corrosion inhibition, chemical reactivity and adsorption of PCB2 on Q235 carbon steel were described by experimental and theoretical studies. The inhibition performance of PCB2 as a green corrosion inhibitor was evaluated by electrochemical and gravimetric tests. The binding active sites and activities thereof on the steel surface were illustrated by quantum chemistry, and the equilibrium configuration was predicted by molecular dynamics simulation. PCB2 exhibits good corrosion inhibition on Q235 steel over a wide temperature range. The electrochemical results show that PCB2 is a mixed inhibitor, and its inhibition efficiency increases with the addition of PCB2 concentration. Moreover, the protective film is formed on the steel and the active corrosion sites are blocked significantly by surface analysis. Additionally, the theoretical calculation proves a strong interaction between PCB2 molecule and carbon steel. Besides, the antimicrobial activity was also preliminarily studied. This suggests that PCB2 exhibits better antimicrobial activity against many Gram-positive and Gram-negative bacteria. As a novel green corrosion inhibitor and antimicrobial agent, PCB2 is worthy of further exploitation.
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Biflavonoides , Catequina , ProantocianidinasRESUMO
Ubiquitous petrochemical-based plastics pose a potential threat to ecosystems. In response, bioderived and degradable polymeric materials are being developed, but their mechanical and thermal properties cannot compete with those of existing petrochemical-based plastics, especially those used as structural materials. Herein, we report a biodegradable plant cellulose nanofiber (CNF)-derived polymeric structural material with high-density reversible interaction networks between nanofibers, exhibiting mechanical and thermal properties better than those of existing petrochemical-based plastics. This all-green material has substantially improved flexural strength (â¼300 MPa) and modulus (â¼16 GPa) compared with those of existing petrochemical-based plastics. Its average thermal expansion coefficient is only 7 × 10-6 K-1, which is more than 10 times lower than those of petrochemical-based plastics, indicating its dimension is almost unchanged when heated, and thus, it has a thermal dimensional stability that is better than those of plastics. As a fully bioderived and degradable material, the all-green material offers a more sustainable high-performance alternative to petrochemical-based plastics.
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Celulose , Nanofibras , Celulose/química , Ecossistema , Nanofibras/química , Plásticos , PolímerosRESUMO
Hydrogel materials have many excellent properties and a wide range of applications. Recently, a new type of hydrogel has emerged: cellulose nanofiber (CNF)-based hydrogels, which have three-dimensional nanofiber networks and unique physical properties. Because CNFs are abundant, renewable, and biodegradable, they are green and eco-friendly nanoscale building blocks. In addition, CNF-based hydrogel materials exhibit excellent mechanical properties and designable functions by different preparation methods and structure designs, demonstrating huge development potential. In this Perspective, we summarize the recent progress in the development of CNF-based hydrogels and introduce their applications in elastic hydrogels, ionic conduction, water purification, and biomedicine, highlighting future trends and opportunities for the further development of CNF-based hydrogels as emerging materials systems.
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Electromagnetic interference (EMI) shielding materials with excellent EMI shielding efficiency (SE), lightweight property, and superb mechanical performance are vitally important for modern society, but it is still a challenge to realize these performances simultaneously on one material. Here, we report a sustainable bioinspired double-network structural material with excellent specific strength (146 MPa g-1 cm3) and remarkable EMI SE (100 dB) from cellulose nanofiber (CNF) and carbon nanotubes (CNTs), which demonstrates remarkable and outstanding performance to both typical metal materials and reported polymer composites. In particular, the bioinspired double-network structure design simultaneously achieves an extremely high electrical conductivity and mechanical strength, which makes it a lightweight, high shielding efficiency, and sustainable structural material for real-life electromagnetic wave shielding applications.
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Hydrogel materials with high water content and good biocompatibility are drawing more and more attention now, especially for biomedical use. However, it still remains a challenge to construct hydrogel fibers with enough strength and toughness for practical applications. Herein, we report a bio-inspired lotus-fiber-mimetic spiral structure hydrogel bacterial cellulose fiber with high strength, high toughness, high stretchability, and energy dissipation, named biomimetic hydrogel fiber (BHF). The spiral-like structure endows BHF with excellent stretchability through plastic deformation and local failure, assisted by the breaking-reforming nature of the hydrogen bonding network among cellulose nanofibers. With the high strength, high stretchability, high energy dissipation, high hydrophilicity, porous structure, and excellent biocompatibility, BHF is a promising hydrogel fiber for biomedicine. The outstanding stretchability and energy dissipation of BHF allow it to absorb energy from the tissue deformation around a wound and effectively protect the wound from rupture, which makes BHF an ideal surgical suture.
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Lotus , Nanofibras , Celulose , Hidrogéis , PorosidadeRESUMO
Long noncoding RNAs (lncRNAs) have been implicated in various biological processes and pathological conditions, including tumorigenesis. However, the exact roles of NEAT1 and its underlying mechanisms in non-small cell lung cancer (NSCLC) remain largely unclear. In the present study, lncRNA NEAT1 was detected to be significantly upregulated in NSCLC tissues and closely associated with advanced TNM stages, lymph node metastasis, distant metastasis, and poor prognosis. Further experiments revealed that lncRNA NEAT1 silencing inhibited cell proliferation and invasion in vitro. In addition, mechanistic analysis showed that lncRNA NEAT1 upregulated the miR-181a-5p-targeted gene HMGB2 through acting as a competitive "sponge" of miR-181a-5p. In conclusion, our study suggested that lncRNA NEAT1 plays an oncogenic role in NSCLC progression and provides potential mechanisms by which lncRNA NEAT1 contributes to this disease.
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Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , MicroRNAs/genética , Interferência de RNA , RNA Longo não Codificante/genética , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Proteína HMGB2/genética , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Carga TumoralRESUMO
The prognostic value of phosphatidylinositol-4, 5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) in patients with esophageal squamous cell carcinoma (ESCC) is controversial. We aimed to investigate the prognostic significance of PIK3CA mutation in patients with ESCC. EMBASE, PubMed, and Web of Science databases were systematically searched from inception through Oct. 3, 2016. The hazard ratios (HRs) and 95% confidence intervals (CI) were calculated using a random effects model for overall survival (OS) and disease-free survival (DFS). Seven studies enrolling 1505 patients were eligible for inclusion of the current meta-analysis. Results revealed that PIK3CA mutation was not significantly associated with OS (HR: 0.90, 95% CI: 0.63-1.30, P=0.591), with a significant heterogeneity (I 2=65.7%, P=0.012). Additionally, subgroup analyses were further conducted according to various variables, such as types of specimen, the sample size, technique and statistical methodology. All results suggested that no significant relationship was found between PIK3CA mutation and OS in patients with ESCC. For DFS, there was no significant association between PIK3CA mutation and DFS in patients with ESCC (HR: 1.00, 95% CI=0.47-2.11, P=0.993, I 2=73.7%). Publication bias was not present and the results of sensitivity analysis were very stable in the current meta-analysis. Our findings suggest that PIK3CA mutation has no significant effects on OS and DFS in ESCC patients. More well-designed prospective studies with better methodology for PIK3CA assessment are required to clarify the prognostic significance of PIK3CA mutation in ESCC patients.
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Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Mutação , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/mortalidade , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Esofágicas/enzimologia , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Seguimentos , Expressão Gênica , Humanos , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Tamanho da AmostraRESUMO
OBJECTIVE: To study the clinical effect of development theory based acupuncture on early cerebral palsy (CP) infants with parafunctional sitting position. METHODS: Totally 120 early CP infants were randomly assigned to two groups equally, the treatment group and the control group. All received acupuncture combined with training rehabilitation. Patients in the treatment group adopted acupuncture based on infants development theory, while those in the control group were treated by head acupuncture. Sitting functional points in Gross motor function measure (GMFM) 88 were observed in different groups and infant patients of various types before and after treatment. Root mean square (RMS) signals of sitting correlated muscles (latissimus dorsi, erector spinae, rectus abdominis) were recorded by surface electromyography (sEMG). The effective rate was evaluated by Nimodipine method. RESULTS: Compared with before treatment, sitting functional points were significantly improved in the two groups (P<0.01). After treatment, it was higher in the treatment group than in the control group (P<0.01). The advance amplitude was higher in CP infants of the spastic type and the hypotonic type than other types (P<0.01). Along with sitting process, latissimus dorsi RMS signals were gradually tapered, erector spinae RMS signals were gradually enhanced, and rectus abdominis RMS signals were slightly weakened. Compared with the control group, latissimus dorsi RMS signals obviously decreased, and erector spinae RMS signals obviously increased in the treatment group after treatment (all P<0.01). The total effective rate was higher in the treatment group than in the control group (89.29% vs. 77.78%, P<0.05). CONCLUSION: Infants development theory based acupuncture could effectively elevate dorsi-extensor muscles force, improve sitting position of 8 months to 1 year old CP infants with parafunctional sitting position.
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Terapia por Acupuntura/métodos , Paralisia Cerebral/terapia , Feminino , Humanos , Lactente , Masculino , Medicina , Postura , Pesquisa , Coluna VertebralRESUMO
The aim of this study was to discuss the new methods of clinical classification and staging of patients with myasthenia gravis (MG) proposed by our group and to summarize the experiences of surgical treatment of MG with a novel incision by cutting the sternum cross-sectionally at the second intercostal level. A retrospective analysis was made for the clinical data from the patients with MG who underwent thymectomy from July 1988 to May 2009. The surgical procedures were designed into three groups, a group with Osserman classification and median incision of the sternum (Group 1), a group with MGFA typing (Myasthenia Gravis Foundation of America) and a small transverse sternal incision at the second intercostal level (Group 2), and a group with new typing and a smaller transverse sternal incision at the second intercostal level (Group 3). Observation of the clinical typing and staging was made in the patients with myasthenia crisis. The parameters such as procedure duration in Group 2 and 3 was significantly lower than those in Group 1 (P < 0.05). The incidence of myasthenia crisis in Group 3 was significantly lower than that in Groups 2 and 3 (P < 0.05). The procedure with a smaller transverse sternal incision at the second intercostal level (Group 3) is a safer method for patients with MG. The combination of this procedure with the new typing and staging methods proposed by our group could facilitate the selection of operation indications and opportunity, resulting in the lower incidence of myasthenia crisis and mortality. Our new procedure is well deserved to be a preferential selection by other hospitals.
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Miastenia Gravis/classificação , Miastenia Gravis/cirurgia , Esterno/cirurgia , Timectomia/métodos , Adolescente , Adulto , Perda Sanguínea Cirúrgica , Estudos de Coortes , Feminino , Seguimentos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Miastenia Gravis/diagnóstico , Duração da Cirurgia , Cuidados Pós-Operatórios/métodos , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Medição de Risco , Timoma/cirurgia , Neoplasias do Timo/cirurgia , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND AND OBJECTIVE: Angiotensin converting enzyme (ACE) gene contains either an insertion (I) allele or a deletion (D) allele forming three potential genotypes: II, ID and DD. The D allele or DD genotype has been reported to be associated with higher plasma ACE level. An assessment of the association between ACE I/D gene polymorphism and idiopathic nephrotic syndrome (INS) susceptibility in children is still controversial. This meta-analysis was performed to evaluate the association between ACE I/D gene polymorphism and the onset of INS. METHOD: A predefined literature search and selection of eligible relevant studies were performed to collect data from electronic databases, and eligible investigations were synthesized using the meta-analysis method. RESULTS: Nine investigations were identified for the analysis of association between ACE I/D gene polymorphism and INS risk in children, including six in Asians, one study for Caucasians and two for Africans. There was positive association between D allele or DD genotype and INS susceptibility in Asians (OR = 1.75, p = 0.01; OR = 2.01, p = 0.02), but not for Caucasian children and Africans (for Caucasians, D: OR=1.35, p = 0.27, DD: OR = 0.95, p = 0.91; for Africans, D: OR = 1.70, p = 0.56, DD: OR = 1.60, p = 0.73). Furthermore, II homozygous seemed to play a positive role against INS onset for Asians (OR = 0.59, p = 0.02), but the link between II genotype and INS risk was not observed in Caucasian children and Africans (Caucasians: OR = 0.31, p = 0.06; Africans: OR = 0.50, p = 0.59). CONCLUSIONS: D allele and DD homozygous might become significant genetic molecular markers for INS susceptibility in Asian children, but the association was not observed in Caucasians or Africans. However, the conclusion from our study cannot be sustained and more investigations on larger sample in different populations are required to further clarify the role of D allele or DD homozygous in the onset of INS in difference races.
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Estudos de Associação Genética , Predisposição Genética para Doença , Mutação INDEL/genética , Síndrome Nefrótica/enzimologia , Síndrome Nefrótica/genética , Peptidil Dipeptidase A/genética , Polimorfismo Genético , Negro ou Afro-Americano/genética , Alelos , Povo Asiático/genética , Criança , Homozigoto , Humanos , Fatores de Risco , População Branca/genéticaRESUMO
BACKGROUND AND OBJECTIVE: The association of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism with the risk of focal segmental glomerulosclerosis (FSGS) is still controversial. A meta-analysis was performed to evaluate the association between ACE I/D gene polymorphism and FSGS susceptibility. METHOD: We performed a predefined literature search and selection of eligible relevant studies to collect data from electronic databases. RESULTS: In total, 12 articles were identified for the analysis of the association between ACE I/D gene polymorphism and FSGS risk. One report included an investigation in Arab and Jewish populations separately. Thus, there were seven reports in Asians, two in Caucasians, one in Africans, two in Arabs and one in Jews. In Asians, there was a markedly positive association between the D allele or DD genotype and FSGS susceptibility (p = 0.008; p = 0.002), and the II genotype may play a protective role against FSGS onset (p = 0.002). However, a link between ACE I/D gene polymorphism and FSGS risk was not found in Caucasians, Africans, Arabs or Jews (Caucasians: D: p = 0.11, DD: p = 0.19, II: p = 0.70; Africans: D: p = 0.40, DD: p = 0.49, II: p = 0.61; Arabs: D: p = 0.34, DD: p = 0.10, II: p = 0.42; Jews: D: p = 0.90, DD: p = 0.97, II: p = 0.83). CONCLUSION: The D allele or DD homozygosity may become a significant genetic molecular marker for the onset of FSGS in Asians, but not for Caucasians, Africans, Arabs or Jews.