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1.
Plant Cell Rep ; 42(5): 939-952, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36964306

RESUMO

KEY MESSAGE: The fusion gene 4CL-CCR promotes lignification and activates lignin-related MYB expression in tobacco but inhibits auxin-related gene expression and hinders the auxin absorption of cells. Given the importance of lignin polymers in plant growth and their industrial value, it is necessary to investigate how plants synthesize monolignols and regulate the level of lignin in cell walls. In our previous study, expression of the Populus tomentosa fusion gene 4CL-CCR significantly promoted the production of 4-hydroxycinnamyl alcohols. However, the function of 4CL-CCR in organisms remains poorly understood. In this study, the fusion gene 4CL-CCR was heterologously expressed in tobacco suspension cells. We found that the transgenic suspension cells exhibited lignification earlier. Furthermore, 4CL-CCR significantly reduced the content of phenolic acids and increased the content of aldehydes in the medium, which led to an increase in lignin deposition. Moreover, transcriptome results showed that the genes related to lignin synthesis, such as PAL, 4CL, CCoAOMT and CAD, were significantly upregulated in the 4CL-CCR group. The expression of genes related to auxin, such as ARF3, ARF5 and ARF6, was significantly downregulated. The downregulation of auxin affected the expression of transcription factor MYBs. We hypothesize that the upregulated genes MYB306 and MYB315 are involved in the regulation of cell morphogenesis and lignin biosynthesis and eventually enhance lignification in tobacco suspension cells. Our findings provide insight into the function of 4CL-CCR in lignification and how secondary cell walls are formed in plants.


Assuntos
Lignina , Nicotiana , Lignina/genética , Plantas Geneticamente Modificadas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Molecules ; 27(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36296473

RESUMO

Soil enzymes, such as invertase, urease, acidic phosphatase and catalase, play critical roles in soil biochemical reactions and are involved in soil fertility. However, it remains a great challenge to efficiently concentrate soil enzymes and sensitively assess enzyme activity. In this study, we synthesized phenylboronic acid-functionalized magnetic nanoparticles to rapidly capture soil enzymes for sensitive soil enzyme assays. The iron oxide magnetic nanoparticles (MNPs) were firstly prepared by the co-precipitation method and then functionalized by (3-aminopropyl)triethoxysilane, polyethyleneimine and phenylboric acid in turn, obtaining the final nanoparticles (MNPPBA). Protein-capturing assays showed that the functionalized MNPs had a much higher protein-capturing capacity than the naked MNPs (56% versus 6%). Moreover, MNPPBA almost thoroughly captured the tested enzymes, i.e., urease, invertase, and alkaline phosphatase, from enzyme solutions. Based on MNPPBA, a soil enzyme assay method was developed by integration of enzyme capture, magnetic separation and trace enzyme analysis. The method was successfully applied in determining trace enzyme activity in rhizosphere soil. This study provides a strategy to sensitively determine soil enzyme activity for mechanistic investigation of soil fertility and plant-microbiome interaction.


Assuntos
Nanopartículas de Magnetita , Solo , Catalase , Urease , Polietilenoimina , beta-Frutofuranosidase , Fosfatase Alcalina , Ensaios Enzimáticos
3.
Small ; 17(46): e2102244, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34363320

RESUMO

Bimetallic nanocrystals (NCs), associated with various surface functions such as ligand effect, ensemble effect, and strain effect, exhibit superior electrocatalytic properties. The stress-induced surface strain effect can alter binding strength between the surface active sites and reactants as well as their intermediates, and the electrochemical performance of bimetallic NCs can be significantly facilitated by the lattice-strain modification via their morphologies, sizes, shell-thickness, surface defectiveness as well as compositions. In this review, an overview of fundamental principles, characterization techniques, and quantitative determination of the surface lattice strain is provided. Various strategies and synthesis efforts on creating lattice-strain-engineered bimetallic NCs, including the de-alloying process, atomic layer-by-layer deposition, thermal treatment evolution, one-pot synthesis, and other efforts are also discussed. It is further outlined how the lattice strain effect promotes electrochemical catalysis through the selected case studies. The reactions on oxygen reduction reaction, small molecular oxidation, water splitting reaction, and electrochemical carbon dioxide reduction reactions are focused. In particular, studies of lattice strain arisen from core-shell nanostructure and defectiveness are highlighted. Lastly, the potential challenges are summarized and the prospects of lattice-strain-based engineering on bimetallic nanocatalysts with suggestion and guidance of the future electrocatalyst design are envisioned.


Assuntos
Nanoestruturas , Ligas , Catálise , Oxirredução
4.
BMC Plant Biol ; 20(1): 528, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213376

RESUMO

BACKGROUND: The characteristics of elephant grass, especially its stem lignocellulose, are of great significance for its quality as feed or other industrial raw materials. However, the research on lignocellulose biosynthesis pathway and key genes is limited because the genome of elephant grass has not been deciphered. RESULTS: In this study, RNA sequencing (RNA-seq) combined with lignocellulose content analysis and cell wall morphology observation using elephant grass stems from different development stages as materials were applied to reveal the genes that regulate the synthesis of cellulose and lignin. A total of 3852 differentially expressed genes (DEGs) were identified in three periods of T1, T2, and T3 through RNA-seq analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of all DEGs showed that the two most abundant metabolic pathways were phenylpropane metabolism, starch and sucrose metabolism, which were closely related to cell wall development, hemicellulose, lignin and cellulose synthesis. Through weighted gene co-expression network analysis (WGCNA) of DEGs, a 'blue' module highly associated with cellulose synthesis and a 'turquoise' module highly correlated with lignin synthesis were exhibited. A total of 43 candidate genes were screened, of which 17 had function annotations in other species. Besides, by analyzing the content of lignocellulose in the stem tissues of elephant grass at different developmental stages and the expression levels of genes such as CesA, PAL, CAD, C4H, COMT, CCoAMT, F5H and CCR, it was found that the content of lignocellulose was related to the expression level of these structural genes. CONCLUSIONS: This study provides a basis for further understanding the molecular mechanisms of cellulose and lignin synthesis pathways of elephant grass, and offers a unique and extensive list of candidate genes for future specialized functional studies which may promote the development of high-quality elephant grass varieties with high cellulose and low lignin content.


Assuntos
Metabolismo dos Carboidratos/genética , Celulose/metabolismo , Genoma de Planta/genética , Lignina/metabolismo , Pennisetum/genética , Transcriptoma , Parede Celular/metabolismo , Perfilação da Expressão Gênica , Lignina/análise , Redes e Vias Metabólicas/genética , Especificidade de Órgãos , Pennisetum/metabolismo , Polissacarídeos/metabolismo , Propano/metabolismo , Análise de Sequência de RNA , Amido/metabolismo , Sacarose/metabolismo
5.
Macromol Rapid Commun ; 41(5): e1900624, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31977130

RESUMO

A 2D conjugated polyelectrolyte (CPE), PBDTTh-TT-NBr, having the same backbone as the highly efficient donor polymer PTB7-Th and the quaternary ammonium pendant, is synthesized as a cathode interlayer (CIL) material for PTB7-Th-based fullerene and non-fullerene solar cells. The quaternary ammonium group is connected to the 2D conjugated backbone by a long, flexible alkyl chain, facilitating the modification of cathode via forming interface dipoles. Moreover, compared with another CPE analogue to PTB7, PBDT-TT-NBr, without the 2D conjugated backbone, the PBDTTh-TT-NBr presents a higher similarity in polymer structure to the donor polymer PTB7-Th. This feature makes it more compatible with the PTB7-Th-based active-layer film, improving the electron transport. With the PBDTTh-TT-NBr as the CIL, devices afford higher performances than those using the PBDT-TT-NBr in both fullerene and non-fullerene systems. This work offers guidance on choosing the CIL material that ought to possess a highly similar structure to the active-layer component.


Assuntos
Polieletrólitos/química , Polímeros/química , Polímeros/síntese química , Compostos de Amônio/química , Eletrodos , Transporte de Elétrons , Fulerenos/química , Microscopia de Força Atômica , Energia Solar , Luz Solar , Propriedades de Superfície
6.
Chemistry ; 19(8): 2711-9, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-23296518

RESUMO

Macromolecular crowding is an ubiquitous phenomenon in living cells that significantly affects the function of enzymes in vivo. However, this effect has not been paid much attention in the research of the immobilization of enzymes onto mesoporous silica. Herein, we report the combined effects of macromolecular crowding and surface hydrophobicity on the performance of an immobilized enzyme by accommodating lipase molecules into a series of mesoporous silicas with different amounts of inert poly(methacrylate) (PMA) covalently anchored inside the nanopores. The incorporation of the PMA polymer into the nanopores of mesoporous silica enables the fabrication of a crowded and hydrophobic microenvironment for the immobilized enzyme and the variation in polymer content facilitates an adjustment of the degree of crowding and surface properties of this environment. Based on this system, the catalytic features of immobilized lipase were investigated as a function of polymer content in nanopores and the results indicated that the catalytic efficiency, thermostability, and reusability of immobilized lipase could all be improved by taking advantage of the macromolecular crowding effect and surface hydrophobicity. These findings provide insight into the possible functions of the macromolecular crowding effect, which should be considered and integrated into the fabrication of suitable mesoporous silicas to improve enzyme immobilization.


Assuntos
Enzimas Imobilizadas/química , Substâncias Macromoleculares/química , Metacrilatos/química , Polímeros/química , Dióxido de Silício/química , Interações Hidrofóbicas e Hidrofílicas , Nanoporos , Propriedades de Superfície
7.
N Biotechnol ; 76: 72-81, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37182820

RESUMO

The development of bacterial cellulose (BC) industrialization has been seriously affected by its production. Mannose/mannan is an essential component in many biomass resources, but Komagataeibacter xylinus uses mannose in an ineffective way, resulting in waste. The aim of this study was to construct recombinant bacteria to use mannose-rich biomass efficiently as an alternative and inexpensive carbon source in place of the more commonly used glucose. This strategy aimed at modification of the mannose catabolic pathway via genetic engineering of K. xylinus ATCC 23770 strain through expression of mannose kinase and phosphomannose isomerase genes from the Escherichia coli K-12 strain. Recombinant and wild-type strains were cultured under conditions of glucose and mannose respectively as sole carbon sources. The fermentation process and physicochemical properties of BC were investigated in detail in the strains cultured in mannose media. The comparison showed that with mannose as the sole carbon source, the BC yield from the recombinant strain increased by 84%, and its tensile strength and elongation were increased 1.7 fold, while Young's modulus was increased 1.3 fold. The results demonstrated a successful improvement in BC yield and properties on mannose-based medium compared with the wild-type strain. Thus, the strategy of modifying the mannose catabolic pathway of K. xylinus is feasible and has significant potential in reducing the production costs for industrial production of BC from mannose-rich biomass.


Assuntos
Escherichia coli K12 , Gluconacetobacter xylinus , Manose/metabolismo , Celulose/química , Escherichia coli K12/metabolismo , Gluconacetobacter xylinus/genética , Gluconacetobacter xylinus/metabolismo , Glucose/metabolismo , Carbono/metabolismo
8.
Adv Sci (Weinh) ; 10(10): e2206120, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36737848

RESUMO

Microplastic (MP) pollution is one of the greatest threats to marine ecosystems. Cold seeps are characterized by methane-rich fluid seepage fueling one of the richest ecosystems on the seafloor, and there are approximately more than 900 cold seeps globally. While the long-term evolution of MPs in cold seeps remains unclear. Here, how MPs have been deposited in the Haima cold seep since the invention of plastics is demonstrated. It is found that the burial rates of MPs in the non-seepage areas significantly increased since the massive global use of plastics in the 1930s, nevertheless, the burial rates and abundance of MPs in the methane seepage areas are much lower than the non-seepage area of the cold seep, suggesting the degradation potential of MPs in cold seeps. More MP-degrading microorganism populations and functional genes are discovered in methane seepage areas to support this discovery. It is further investigated that the upwelling fluid seepage facilitated the fragmentation and degradation behaviors of MPs. Risk assessment indicated that long-term transport and transformation of MPs in the deeper sediments can reduce the potential environmental and ecological risks. The findings illuminated the need to determine fundamental strategies for sustainable marine plastic pollution mitigation in the natural deep-sea environments.


Assuntos
Ecossistema , Sedimentos Geológicos , Plásticos , Microplásticos , Metano/metabolismo
9.
Langmuir ; 28(25): 9788-96, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22642540

RESUMO

The highly ordered mesoporous silicas with elaborately controlled microenvironment were synthesized via covalent incorporation of long-chain polymers (M(w) = 2000 g mol(-1)) bearing specific hydrophilic/hydrophobic balance. The microenvironment (hydrophilicity/hydrophobicity) of the mesoporous silicas was quantitatively determined by gas adsorption experiments and investigated by lysozyme (LYZ) adsorption. The relative activity of lipase from Pseudomonas cepacia (PCL) encapsulated in the mesoporous silica with moderate hydrophobic microenvironment (hereafter denoted as MHM) reaches up to 281% compared with the free PCL, notably higher than that of PCL accommodated in the mesoporous silicas with hydrophilic or strong hydrophobic microenvironment (20.7-26.2% relative to the free PCL). Moreover, PCL entrapped in the nanochannels with MHM affords the highest initial rate in the kinetic resolution of (R,S)-1-phenylethanol relative to other immobilized PCL. The above results suggest that the MHM could render the active center of PCL entirely exposed to the substrates without interrupting its native conformation in the "interfacial activation". In addition, the nanochannels with MHM could markedly improve the thermal stability of PCL (preserving nearly 60% of the initial activity after the incubation at 70 °C for 2 h) and facilitate the recycling of the immobilized PCL in both aqueous and organic media. Our work demonstrates that the subtle modulation of the microenvironment of mesoporous silicas for enzyme immobilization designates a very promising strategy to fabricate the highly active and stable heterogeneous biocatalysts for industrial application.


Assuntos
Biocatálise , Lipase/química , Lipase/metabolismo , Polímeros/química , Dióxido de Silício/química , Adsorção , Burkholderia cepacia/enzimologia , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Cinética , Muramidase/química , Muramidase/metabolismo , Compostos de Organossilício/química , Álcool Feniletílico/química , Álcool Feniletílico/metabolismo , Porosidade
10.
Zookeys ; 1103: 1-23, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761786

RESUMO

This study describes the fine structure of the mouthparts, antennae, forewings, and brochosomes of two leafhopper species belonging to the typhlocybine tribe Erythroneurini collected from the Karst area of Guizhou Province, southern China: Singaporashinshana, which prefers woody dicot hosts, and Empoascanarasipra, which feeds on grasses. As in other leafhoppers, the piercing-sucking mouthparts consist of a conical labrum, a cylindrical three-segmented labium, and a slender stylet fascicle. The labrum of both species has no sensilla and the labium has several common types of sensilla, but the two species differ in the numbers, types, and distribution of sensilla and in other aspects of the surface sculpture of the mouthparts. The stylet fascicle has distinctive dentition on both the maxillary and mandibular stylets. The antennae of the two species differ in several respects, including the sensilla and sculpture of the scape, pedicel, and flagellum, as well as the degree of sub-segmentation of the flagellum. Except for the variable scaly structure and rounded protrusions on the surface of S.shinshana, the fine structure of the forewing surfaces of the two species are similar to those of other leafhoppers. Only small spherical brochosomes were found on the body surface of S.shinshana and E.sipra. Similar studies of additional erythroneurine species are needed to determine whether differences in mouthpart and antennal fine structure may reflect adaptation to different host plant.

11.
Appl Biochem Biotechnol ; 194(7): 3212-3227, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35349090

RESUMO

Chemoautotrophic bacterium Ralstonia eutropha H16 can fix CO2 to bioplastic and is potentially useful for CO2 neutralization. Targeting the solar fuel-based plastic biomanufactory, the polyhydroxybutyrate (PHB) production between heterotrophy and chemoautotrophy conditions was evaluated and the proteomic responses of the R. eutropha H16 cells to different carbon and energy sources were investigated. The results show that the chemoautotrophic mode hardly affected the cellular PHB accumulation capacity. Benefited from the high coverage proteome data, the global response of R. eutropha H16 to different carbon and energy sources was presented with a 95% KEGG pathway annotation, and the genome-wide location-related protein expression pattern was also identified. PHB depolymerase Q0K9H3 was found as a key protein responding to the low carbon input while CO2 and H2 were used, and will be a new regulation target for further high PHB production based on solar fuels.


Assuntos
Cupriavidus necator , Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Cupriavidus necator/genética , Cupriavidus necator/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Proteômica
12.
RSC Adv ; 12(50): 32219-32229, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36425700

RESUMO

Post-extraction, preventing the absorption of alveolar ridge to retain the supporting construction for implanted teeth is still a challenge. Herein, we developed modified chitosan (CS)-based hydrogel using N-hydroxysuccinimide-terminated 4-arm poly (ethylene glycol) (4-arm-PEG-NHS) as the crosslinking agent, after introducing it to the polyhexamethyleneguanidine hydrochloride (PHMB) solution, CS/PEG/PHMB hydrogel with the enhanced antibacterial properties was obtained. The CS/PEG hydrogel and CS/PEG/PHMB hydrogel prepared here showed excellent mechanical strength and their compressive strength could reach 440 kPa and 450 kPa, respectively. The composite hydrogel was designed to be directional porous, low cytotoxic, pH-sensitive, and degradable. The weight of the hydrogel was reduced by ∼30% after 28 days of incubation, and it swelled significantly in the acidic condition while it did not swell in the neutral and weakly alkaline environments, indicating an excellent biodegradability in the inflammation site. In vitro antibacterial experiments showed that the bacteriostatic rate of the CS/PEG/PHMB hydrogel against S. aureus was above 90%, which could effectively inhibit the spread of the bacteria and inflammation in the alveolar ridge. Additionally, the hybrid hydrogels demonstrated good biocompatibility with the NIH 3T3 fibroblast cells. Overall, the CS/PEG/PHMB hydrogel is a promising biological scaffold for maintaining the alveolar ridge and subsequently improving the success rate of the dental implant.

13.
Commun Biol ; 5(1): 1125, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36284165

RESUMO

Populus wilsonii is an important species of section Leucoides, and the natural populations mainly grow in southwest China. In this study, a single genotype of wild P. wilsonii was sequenced and assembled at genome size of 477.35 Mb in 19 chromosomes with contig N50 of 16.3 Mb. A total of 38,054 genes were annotated, and 49.95% of the genome was annotated as repetitive elements. Phylogenetic analysis identified that the divergence between P. wilsonii and the ancestor of P. deltoides and P. trichocarpa was 12 (3-23) Mya. 4DTv and Ks distributions supported the occurrence of the salicoid WGD event (~65 Mya). The highly conserved collinearity supports the close evolutionary relationship among these species. Some key enzyme-encoding gene families related to the biosynthesis of lignin and flavonoids were expanded and highly expressed in the stems or leaves, which probably resist the damage of the natural environment. In addition, some key gene families related to cellulose biosynthesis were highly expressed in stems, accounting for the high cellulose content of P. wilsonii variety. Our findings provided deep insights into the genetic evolution of P. wilsonii and will contribute to further biological research and breeding as well as for other poplars in Salicaceae.


Assuntos
Populus , Populus/genética , Filogenia , Lignina , Melhoramento Vegetal , Cromossomos , Flavonoides
14.
Mol Ecol Resour ; 22(6): 2363-2378, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35347881

RESUMO

Elephant grass (Pennisetum purpureum Schum) is an important forage, biofuels and industrial plant widely distributed in tropical and subtropical areas globally. It is characterized with robust growth and high biomass. We sequenced its allopolyploid genome and assembled 2.07 Gb into A' and B subgenomes of 14 chromosomes with scaffold N50 of 8.47 Mb, yielding a total of 77,139 genes. The allotetraploid speciation occurred approximately 15 Ma after the divergence between Setaria italica and Pennisetum glaucum, according to a phylogenetic analysis of Pennisetum species. Double whole-genome duplication (WGD) and polyploidization events resulted in large-scale gene expansion, especially in the key steps of growth and biomass accumulation. Integrated transcriptome profiling revealed the functional divergence between subgenomes A' and B. A' subgenome mainly contributed to plant growth, development and photosynthesis, whereas the B subgenome was primarily responsible for effective transportation and resistance to stimulation. Some key gene families related to cellulose biosynthesis were expanded and highly expressed in stems, which could explain the high cellulose content in elephant grass. Our findings provide deep insights into genetic evolution of elephant grass and will aid future biological research and breeding, even for other grasses in the family Poaceae.


Assuntos
Cenchrus , Pennisetum , Biomassa , Celulose , Cenchrus/genética , Cromossomos , Pennisetum/genética , Filogenia , Melhoramento Vegetal
15.
Inorg Chem ; 50(8): 3198-205, 2011 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-21395253

RESUMO

Four novel metal-organic coordination polymers with the formulas Mn(3)(btdc)(3)(DMF)(4) (1), Co(btdc)(DMF)(3) (2), Zn(btdc)(DMF)(3) (3), and Zn(btdc)(4,4'-bpy)(0.5) (4), where H(2)btdc = 2,2'-bithiophene-5,5'-dicarboxylic acid, DMF = N,N'-dimethylformamide, and 4,4'-bpy = 4,4'-bipyridine, have been successfully synthesized. Crystal 1 with Mn(2+) as the cation features a three-dimensional (3D) infinite framework built from trimanganese clusters, and crystals 2 and 3 with Co(2+) and Zn(2+), respectively, as the cation both have one-dimensional zigzag polymeric coordination chains. Crystal 4 synthesized using a mixture of 4,4'-bpy and H(2)btdc exhibits a triply interpenetrating 3D framework built from a dizinc paddlewheel second building unit with a distorted primitive cubic single net. The results of UV/vis spectra indicate that metal binding does not disturb the detailed electronic structure of the ligand. We also demonstrate that Zn(2+) can greatly enhance the luminescence emission of the H(2)btdc ligand, and the emission intensity of crystal 4 is almost 20 times higher than that of the free H(2)btdc ligand. Steady-state and time-resolved spectroscopic measurement reveal that the more rigid environment of the btdc ligand can stabilize the highly excited long-lived states in metal-organic frameworks (MOFs), which thus greatly changes the emission properties of MOFs.


Assuntos
Ácidos Dicarboxílicos/química , Luminescência , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Polímeros/química , Tiofenos/química , Cobalto/química , Manganês/química , Modelos Moleculares , Estrutura Molecular , Zinco/química
16.
Artigo em Zh | MEDLINE | ID: mdl-32842207

RESUMO

Objective:To summarize the cases of temporomandibular joint herniation into external auditory canal found and treated in our hospital, to improve the understanding of oral and maxillofacial diseases and otological diseases, and to explore the potential long-term effects of local radiotherapy on temporomandibular joint function. Method:Analyzed the causes of temporomandibular joint herniation into external auditory canal comprehensively through combining history, clinical manifestations and imaging examination. Result:All otoscope results showed soft tissue mass in the deep anterior wall of the external auditory canal. The soft tissue mass moved inside and outside along with the opening and closing of the mouth. CT examination revealed obvious bone defects in the anterior wall of the ear canal. Conclusion:Delayed radiotherapy injury may be a inducing factor of temporomandibular joint herniation into external auditory canal. CT and MRI examination have guiding significance on the disease treatment selection. The specific signs found by otoscope can confirm the diagnosis.


Assuntos
Otopatias , Transtornos da Articulação Temporomandibular , Meato Acústico Externo , Hérnia , Humanos , Articulação Temporomandibular
17.
J Biomater Sci Polym Ed ; 29(16): 1933-1948, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29920156

RESUMO

Chinese giant salamander (CGS) has high medicinal value and long history of clinical use in ancient China. In this study, CGS skin (CGSS) collagen was extracted and purified to prepare collagen sponge by freeze-drying. TEMPO oxidized microfibrillated cellulose (TEMPO-MFC) and genipin were adopted to improve the mechanical properties of collagen sponge. The hygroscopicity, porosity, mechanical properties, hemostatic performance, morphology, and biodegradability of the resultant sponges were investigated in detail. The results indicated that CGSS collagen was type I collagen with intact triple-helical structure, and the prepared sponge had porous structure and excellent hemostatic performance with procoagulant ratio of 53.28%. However, the CGSS collagen sponge showed low tensile strength (TS) of 98.80 KPa, compression strength (CS) of 1.48 KPa, and elongation at break (E) of 4.72%. Incorporating 2.5% TEMPO-MFC into the native CGSS collagen sponge resulted in an increase of 188.26% in TS to 284.80 KPa, 166.89% in CS to 3.95 KPa, and 73.52% in E to 8.19%. The improvements were attributed to the physical filling of TEMPO-MFC in cavity and cavity wall of collagen sponge and the stable chemical linkage between carboxyl of TEMPO-MFC and amino group of collagen which effectively improved the toughening of sponge and formed good interface bonding, respectively. Subsequent 0.3% genipin treatment further improved the TS to 605.00 KPa and the CS to 8.66 KPa as a result of crosslinking reaction. Moreover, the composite reinforcing also improved the anti-degradation ability and procoagulant ratio of collagen sponge. All results suggested that the TEMPO-MFC toughened and genipin crosslinked CGSS composite collagen sponge is a promising rapid hemostatic material with high-strength and can be applicated in biomedical field.


Assuntos
Materiais Biocompatíveis/química , Colágeno Tipo I/química , Hemostáticos/química , Pele/química , Urodelos/metabolismo , Animais , Materiais Biocompatíveis/farmacologia , Reagentes de Ligações Cruzadas/química , Hemostáticos/farmacologia , Humanos , Iridoides/química , Porosidade , Propriedades de Superfície
18.
Rev Sci Instrum ; 85(4): 046105, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24784683

RESUMO

Deep UV Raman spectrograph with the laser excitation line down to 177.3 nm was developed in this laboratory. An ellipsoidal mirror and a dispersed-subtractive triple monochromator were used to collect and disperse Raman light, respectively. The triple monochromator was arranged in a triangular configuration with only six mirrors used. 177.3 nm laser excited Raman spectrum with cut-off wavenumber down to 200 cm(-1) and spectral resolution of 8.0 cm(-1) can be obtained under the condition of high purity N2 purging. With the C-C σ bond in Teflon selectively excited by the 177.3 nm laser, resonance Raman spectrum of Teflon with good quality was recorded on the home-built instrument and the σ-σ(*) transition of C-C bond was studied. The result demonstrates that deep UV Raman spectrograph is powerful for studying the systems with electronic transition located in the deep UV region.


Assuntos
Lasers , Análise Espectral Raman , Raios Ultravioleta , Nitrogênio/análise , Politetrafluoretileno/análise , Espectrofotometria Ultravioleta/instrumentação , Espectrofotometria Ultravioleta/métodos , Análise Espectral Raman/instrumentação , Análise Espectral Raman/métodos
19.
Mol Immunol ; 55(3-4): 264-74, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23522926

RESUMO

Interleukin-27 (IL-27), a novel IL-6/IL-12 family cytokine, plays an important role in the early regulation of Th1 responses. The cytokine IL-27 can exert a variety of immune-regulatory functions including cytotoxic T lymphocyte (CTL), CD4+, CD8+ T lymphocytes activation and interferon-γ (IFN-γ) production. In this study, we developed an effective and gene modified tumor cell vaccine. Lewis lung cancer cell LL/2 transfected with the DOTAP:cholesterol cationic liposome could express the mouse IL-27 (mIL-27) gene at a relative high level. The resultant transfectants were then irradiated with X-ray and used as a tumor cell vaccine. This tumor cell vaccine not only contained tumor associated antigen (TAA) of LL/2 cells but also secreted mIL-27 which could induce immune response in mice. The mice vaccinated with LL/2-mIL-27 performed strong tumor inhibiting effect accompanied with a high IFN-γ production. Both CD4+ and CD8+ T lymphocytes were significantly elevated in these mice vaccinated with LL/2-mIL-27 cell vaccine. Moreover, after depletion of CD4+, CD8+ T lymphocytes by injection of antibodies against CD4 and CD8, the vaccinated mice inoculated with autologous LL/2 cells were not protected from tumor challenge. In contrast, vaccinated mice inoculated with autologous LL/2 cells were treated with antibody against natural killer (NK)cells or normal rat IgG still possessed strong antitumor activity. Our data suggested that DOTAP:cholesterol cationic liposome was quite useful in generating an autologous tumor cell vaccine and mIL-27 could be therapeutically used to potentiate the host antitumor immunity.


Assuntos
Vacinas Anticâncer/uso terapêutico , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/terapia , Engenharia Genética/métodos , Interleucinas/metabolismo , Animais , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Ácidos Graxos Monoinsaturados , Feminino , Imunoterapia Adotiva/métodos , Interleucinas/biossíntese , Interleucinas/genética , Lipossomos , Camundongos , Camundongos Endogâmicos C57BL , Compostos de Amônio Quaternário , Ratos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Transfecção
20.
Chem Commun (Camb) ; 48(35): 4190-2, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22436969

RESUMO

A facile synthesis of polymer-inorganic hybrid hollow mesoporous nanospheres was developed based on the entrapment of a dissolved polymer core template in the framework during the assembly process of the hybrid hollow nanospheres for efficient and size-selective enrichment of target peptides/proteins from complex biosamples.


Assuntos
Nanosferas/química , Peptídeos/química , Polímeros/química , Proteínas/química , Polimetil Metacrilato/química , Porosidade , Dióxido de Silício/química
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