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1.
Proc Natl Acad Sci U S A ; 119(41): e2211059119, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36191201

RESUMO

All-solid-state Li-metal batteries (ASSLBs) are highly desirable, due to their inherent safety and high energy density; however, the irregular and uncontrolled growth of Li filaments is detrimental to interfacial stability and safety. Herein, we report on the incorporation of piezo-/ferroelectric BaTiO3 (BTO) nanofibers into solid electrolytes and determination of electric-field distribution due to BTO inclusion that effectively regulates the nucleation and growth of Li dendrites. Theoretical simulations predict that the piezoelectric effect of BTO embedded in solid electrolyte reduces the driving force of dendrite growth at high curvatures, while its ferroelectricity reduces the overpotential, which helps to regularize Li deposition and Li+ flux. Polarization reversal of soft solid electrolytes was identified, confirming a regular deposition and morphology alteration of Li. As expected, the ASSLBs operating with LiFePO4/Li and poly(ethylene oxide) (PEO)/garnet solid electrolyte containing 10% BTO additive showed a steady and long cycle life with a reversible capacity of 103.2 mAh g-1 over 500 cycles at 1 C. Furthermore, the comparable cyclability and flexibility of the scalable pouch cells prepared and the successful validation in the sulfide electrolytes, demonstrating its universal and promising application for the integration of Li metal anodes in solid-state batteries.

2.
Small ; 17(8): e2006373, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33522133

RESUMO

Up to now, the silicon-graphite anode materials with commercial prospect for lithium batteries (LIBs) still face three dilemmas of the huge volume effect, the poor interface compatibility, and the high resistance. To address the above challenges, micro-nano structured composites of graphite coating by ZnO-incorporated and carbon-coated silicon (marked as Gr@ZnO-Si-C) are reasonably synthesized via an efficient and convenient method of liquid phase self-assembly synthesis combined with annealing treatment. The designed composites of Gr@ZnO-Si-C deliver excellent lithium battery performance with good rate performance and stable long-cycling life of 1000 cycles with reversible capacities of 1150 and 780 mAh g-1 tested at 600 and 1200 mA g-1 , respectively. The obtained results reveal that the incorporated ZnO effectively improve the interface compatibility between electrolyte and active materials, and boost the formation of compact and stable surface solid electrolyte interphase layer for electrodes. Furthermore, the pyrolytic carbon layer formed from polyacrylamide can directly improve electrical conductivity, decrease polarization, and thus promote their electrochemical performance. Finally, based on the scalable preparation of Gr@ZnO-Si-C composites, the pouch full cells of Gr@ZnO-Si-C||NCM523 are assembled and used to evaluate the commercial prospects of Si-graphite composites, offering highly useful information for researchers working in the battery industry.

3.
Crit Rev Food Sci Nutr ; 60(12): 2011-2033, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31547671

RESUMO

Lignin is the second most abundant biorenewable polymers only next to cellulose and is ubiquitous in various plant foods. In food industry, lignin often presented as a major component of by-products from plant foods. In the last decade, the food and nutritional interests of lignin attracted more and more attentions and great progresses have been accomplished. In the present review, the structure, physicochemical properties, dietary occurrence and preparation methods of lignin from food resources were summarized. Then, the versatile activities of food lignin were introduced under the subtitles of antioxidant, antimicrobial, antiviral, antidiabetic and other activities. Finally, the potential applications of food lignin were proposed as a food bioactive ingredient, an improver of food package films and a novel material in fabricating drug delivery vehicles and contaminant passivators. Hopefully, this review could bring new insights in exploiting lignin from nutrition- and food-directed views.


Assuntos
Tecnologia de Alimentos/métodos , Lignina , Sistemas de Liberação de Medicamentos , Humanos
4.
Int J Biol Macromol ; 236: 124002, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36914058

RESUMO

Ozonation is an efficient method for improving the technical performance of some starches, but the feasibility of its use for sweet potato starch remains unknown. The effects of aqueous ozonation on the multi-scale structure and physicochemical properties of sweet potato starch were explored. Structurally, ozonation did not generate significant alterations at the granular level (size, morphology, lamellar structure, and long-range and short-range ordered structures), but led to tremendous changes at the molecular level, including converting hydroxyl groups to carbonyl and carboxyl groups and depolymerizing starch molecules. These structural changes resulted in prominent alternations in the technological performance of sweet potato starch, such as increases in water solubility and paste clarity and decreases in water absorption capacity, paste viscosity, and paste viscoelasticity. For these traits, their amplitudes of variation elevated when the ozonation time was extended and peaked at the longest ozonation time (60 min). The greatest changes in paste setback (30 min), gel hardness (30 min), and the puffing capacity of the dried starch gel (45 min) were observed at moderate ozonation times. In summary, aqueous ozonation is a new method for fabricating sweet potato starch with improved functionality.


Assuntos
Ipomoea batatas , Ozônio , Amido/química , Estrutura Molecular , Ipomoea batatas/química , Fenômenos Químicos , Viscosidade
5.
Adv Sci (Weinh) ; 9(4): e2103786, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34796692

RESUMO

Eliminating the uncontrolled growth of Li dendrite inside solid electrolytes is a critical tactic for the performance improvement of all-solid-state Li batteries (ASSLBs). Herein, a strategy to swallow and anchor Li dendrites by filling Si nanoparticles into the solid electrolytes by the lithiation effect with Li dendrites is proposed. It is found that Si nanoparticles can lithiate with the adjacent Li dendrites which have a strong electron transport ability. Such effect can inhibit the formation of Li dendrites at the interface of Li anode, and also swallow the tip Li inside the solid electrolytes, and thus inhibiting its longitudinal growth and avoiding the solid electrolyte puncturing. As a proof of concept, a novel sandwich-structure solid electrolyte of Li6.7 La3 Zr2 Al0.1 O12 (LLZA)-PEO/Si-PEO electrolyte/ (LLZA)-PEO with asymmetrical structure is first constructed and demonstrated stable Li plating/stripping over 1800 h and remarkably improved cycling stability in Li/LiFePO4 cells with a reversible capacity of 111.9 mAh g-1 at 1 C after 150 cycles. The proof of lithiation of Si-PEO electrolyte in the interlayer is also verified. Furthermore, the pouch cell thus prepared exhibits comparable cyclic stability and is allowable for folding and cutting, suggesting its promising application in ASSLBs by this simple and efficient strategy.

6.
RSC Adv ; 8(74): 42438-42445, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-35558412

RESUMO

3D plum candy-like NiCoMnO4 microspheres have been prepared via ultrasonic spraying and subsequently wrapped by graphene through electrostatic self-assembly. The as-prepared NiCoMnO4 powders show hollow structures and NiCoMnO4@graphene exhibits excellent electrochemical performances in terms of rate performance and cycling stability, achieving a high reversible capacity of 844.6 mA h g-1 at a current density of 2000 mA g-1. After 50 cycles at 1000 mA g-1, NiCoMnO4@graphene delivers a reversible capacity of 1045.1 mA h g-1 while the pristine NiCoMnO4 only has a capacity of 143.4 mA h g-1. The hierarchical porous structure helps to facilitate electron transfer and Li-ion kinetic diffusion by shortening the Li-ion diffusion length, accommodating the mechanical stress and volume change during the Li-ion insertion/extraction processes. Analysis from the electrochemical performances reveals that the enhanced performances could be also attributed to the reduced charge-transfer resistance and enhanced Li-ion diffusion kinetics because of the graphene-coating. Moreover, Schottky electric field, due to the difference in work function between graphene and NiCoMnO4, might be favorable for the redox activity of the NiCoMnO4. In light of the excellent electrochemical performance and simple preparation, we believe that 3D plum candy-like NiCoMnO4@graphene composites are expected to be applied as a promising anode materials for high-performance lithium ion batteries.

7.
J Leukoc Biol ; 80(3): 529-37, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16793916

RESUMO

Invasive aspergillosis is a major cause of morbidity and mortality in the severely immunocompromised. The paucity of information about the mechanisms by which Aspergillus-derived factors regulate antigen-specific T cell responses in vivo poses a significant hurdle for devising effective immunization strategies to treat or prevent aspergillosis. By monitoring adoptively transferred T cell receptor transgenic, naive CD4+ (OT-II) and CD8+ (OT-I) T cells specific for distinct peptides of a nominal antigen, chicken ovalbumin (OVA), we demonstrate that sensitization with Aspergillus fumigatus (Af) extract plus OVA protein considerably enhances OT-I and OT-II T cell activation, which results in clonal expansion, primarily as a result of increased proliferation. The sensitization provided by Af extract promotes OT-I expansion accompanied by differentiation into interferon-gamma-producing cytotoxic cells. It is surprising that no effector differentiation of the induced OT-II response was observed. Moreover, the Af extract-induced OT-I and OT-II T cell expansion was transient, as considerable contraction in the numbers of detectable OT-I and OT-II T cells was evidenced by Day 10. In agreement with these observations, sensitization with Af extract plus OVA marginally promoted host immunity against an OVA-expressing thymoma (E.G7) challenge, and the protection was enhanced by resensitization with Af extract and OVA. Our results demonstrate the ability of Af extract to differentially regulate antigen-specific CD4+ and CD8+ T cell responses, resulting in limited augmentation of host immunity. This information suggests that strategies to target CD4+ T cell effector maturation may promote host immunity to Aspergillus and unexpectedly demonstrates the use for Af extract as a CD8+ T cell adjuvant.


Assuntos
Aspergillus fumigatus/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Adjuvantes Imunológicos , Transferência Adotiva , Animais , Aspergillus fumigatus/química , Diferenciação Celular/imunologia , Proliferação de Células , Galinhas , Imunidade Celular/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ovalbumina/imunologia
8.
Thromb Haemost ; 87(4): 684-91, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12008952

RESUMO

We report the molecular genetic analysis of a patient with thrombasthenic phenotype. The lack of surface platelet GPIIb-IIIa complexes and the presence of GPIIIa suggested it was a case of type I Glanzmann's thrombasthenia due to a mutation in GPIIb. Single stranded conformational polymorphism analysis (SSCP) of exon-19 of GPIIb showed polymorphic DNA bands. The DNA sequence of exon-19 revealed the presence of a homozygous C1882T transition that changes residue R597 to STOP codon. Since no other mutations were found in either GPIIb or GPIIIa it is concluded that the C1882T substitution in GPIIb is responsible for the thrombasthenic phenotype of the patient. The lack of platelet GPIIb-mRNA in the proband indicates instability of the [C1882T]GPIIb-mRNA. Coexpression of normal GPIIIa and GPIIb(delta597-1008) in CHO cells failed to show surface expression of GPIIb(delta597-1008)-IIIa complexes. Immunoprecipitation analysis demonstrated that GPIIb(delta597-1008) may indeed complex GPIIIa; however, the association is either unstable or incapable of progressing along the secretory pathway.


Assuntos
Códon sem Sentido , Transtornos Hemorrágicos/genética , Integrina beta3/metabolismo , Glicoproteína IIb da Membrana de Plaquetas/genética , Deleção de Sequência , Trombastenia/genética , Animais , Células CHO , Criança , Códon de Terminação/genética , Cricetinae , Cricetulus , Análise Mutacional de DNA , Éxons/genética , Humanos , Masculino , Linhagem , Fenótipo , Glicoproteína IIb da Membrana de Plaquetas/química , Glicoproteína IIb da Membrana de Plaquetas/metabolismo , Polimorfismo Conformacional de Fita Simples , Testes de Precipitina , Mapeamento de Interação de Proteínas , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/genética , Transfecção
9.
Oncol Rep ; 11(1): 231-6, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14654931

RESUMO

DNA from 45 primary prostate tumors and corresponding normal tissues were analyzed to detect whether the alterations of transforming growth factor beta receptor II (TGFbetaRII) and insulin growth factor receptor II (IGFRII) are associated with microsatellite instability (MSI). We identified that 25 tumors were microsatellite unstable (55%). The remaining 20 tumors are found to be microsatellite stable. Loss of heterozygosity (LOH) was also tested at various loci. Results indicate that in case of TGFbetaRII, the rate of frame-shift mutation depends on the number of polyadenine [poly(A)] tracts. Twelve percent of the tumors had frame-shift alteration at BAT-RII locus which has 10 poly(A) repeats. Twenty percent of the tumors had frame-shift at BAT-25 locus which has 25 poly(A) repeats. In addition, IGFRII gene was examined for the presence of mutation in the repetitive sequences. Seven of the 25 tumors showed deletion of a G within eight poly(G) repeats. Besides these changes there were two tumors which showed a novel insertion of A within this poly(G) repeat making a change in 9 samples (R4, 36%). On the other hand, 4 tumors showed changes within the 5CT repeats. In addition, 3 tumors showed another novel insertion of C within the CT repeats.


Assuntos
Repetições de Microssatélites/genética , Neoplasias da Próstata/patologia , Receptor IGF Tipo 2/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Sequência de Bases , Análise Mutacional de DNA , DNA de Neoplasias/química , DNA de Neoplasias/genética , Humanos , Perda de Heterozigosidade , Masculino , Mutagênese Insercional , Reação em Cadeia da Polimerase , Neoplasias da Próstata/genética , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo II , Deleção de Sequência
10.
Exp Dermatol ; 15(1): 51-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16364031

RESUMO

We have selectively targeted monocyte/macrophages overexpressing an immunomodulatory molecule, latency-associated peptide (LAP), a naturally occurring antagonist for transforming growth factor-beta1, to murine skin utilizing UV light to produce a cutaneous influx of transduced monocyte/macrophages. Bone marrow (BM) cells from BALB/c mice were transduced in vitro with a retroviral construct containing green fluorescent protein (GFP) for detection and human LAP (hLAP) as a test molecule. The transduced BM cells were then cultured in vitro with granulocyte-macrophage colony-stimulating factor (GM-CSF) to produce differentiation to monocyte/macrophages. More than 80% of transduced BM cells were CD11b-positive and MOMA-positive by fluorescence-activated cell-sorter analysis and secreted LAP by ELISA after 10 days of culture in granulocyte-macrophage colony-stimulating factor (GM-CSF). Transduced monocyte/macrophages containing either GFP or hLAP-GFP were then injected intravenously into BALB/c mice. One-half of recipients in each group were exposed to UVB (72 mJ) to induce monocyte/macrophage infiltration into skin. Recipients were sacrificed 60 h after UV irradiation. We found transduced cutaneous macrophages expressing GFP by examining with fluorescence microscopy frozen skin sections of recipient mice immunostained with antibodies to GFP and to macrophage marker F4/80. We identified hLAP sequences by polymerase chain reaction (PCR) of total DNA in recipient blood and UV-irradiated skin but not in unirradiated skin. LAP sequences were also detected at much lower levels in other organs (lung, spleen, and liver) by PCR. Therefore, we have shown that genetically altered monocytic cells can be injected intravenously and targeted to mouse skin by UV exposure. This macrophage-based gene-transfer method may be a potentially useful immunotherapeutic approach for delivering monocyte/macrophage-derived products to skin.


Assuntos
Macrófagos/fisiologia , Monócitos/fisiologia , Pele/efeitos da radiação , Transdução Genética/métodos , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/fisiologia , Técnicas de Cultura de Células , Sistemas de Liberação de Medicamentos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Macrófagos/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/efeitos da radiação , Fragmentos de Peptídeos/biossíntese , Precursores de Proteínas/biossíntese , Retroviridae , Pele/patologia , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta1 , Raios Ultravioleta
11.
J Immunol ; 173(2): 900-9, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15240677

RESUMO

Cytokines that use the common receptor gamma-chain for regulating CD8(+) T cell responses to Ag include IL-2, IL-15, and the recently identified IL-21. The ability of these cytokines to regulate antitumor activity in mice has generated considerable interest in understanding their mode of action. In this study we compare the abilities of IL-2, IL-15, and IL-21 to stimulate immunity against tumors in a syngeneic thymoma model. Durable cures were only achieved in IL-21-treated mice. By monitoring both endogenous and adoptively transferred tumor Ag-specific CD8(+) T cells, it was determined that IL-21 activities overlap with those of IL-2 and IL-15. Similar to IL-2, IL-21 enhanced Ag activation and clonal expansion. However, unlike IL-2 treatment, which induces activation-induced cell death, IL-21 sustained CD8(+) T cell numbers long term as a result of increased survival, an effect often attributed to IL-15. These findings indicate that the mechanisms used by IL-21 to promote CD8(+) T cell responses offer unique opportunities for its use in malignant diseases and infections.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunidade/imunologia , Interleucina-15/fisiologia , Interleucina-2/fisiologia , Interleucinas/fisiologia , Neoplasias/imunologia , Transferência Adotiva , Animais , Linfócitos T CD8-Positivos/fisiologia , Imunidade/fisiologia , Camundongos
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