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1.
Dev Comp Immunol ; 104: 103571, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31837379

RESUMO

To elucidate the immunity-protecting role of the interferon-ß promoter stimulator-1 (ScIPS-1) in barbel chub Squaliobarbus curriculus, the full-length cDNA of ScIPS-1 was cloned and expression levels in response to stimulation were investigated. In addition, the function of ScIPS-1 and its domains were analyzed. The full-length cDNA of ScIPS-1 is 2524 bp and encodes 601 aa. The N-terminal caspase activation and recruitment domain, central proline-rich domain, C-terminal transmembrane domain, C2HC-zinc finger, and Cwf21 domains were identified. The mRNA level of ScIPS-1 was the highest in the kidney, whereas the highest protein level was observed in the liver. The ScIPS-1 expressions were significantly up-regulated after lipopolysaccharide and poly I:C treatment. The ScIPS-1 protein level was up-regulated at 12 h in the head kidney and was up-regulated at 12 h and then down-regulated from 12 to 48 h in the liver after grass carp reovirus (GCRV) infection. The CiIFN and CiMx transcription levels were significantly enhanced in pEGFP-C1-IPS-1 and pcDNA3.1-ΔCwf21 overexpressing cells after GCRV infection. The results indicate that ScIPS-1 may function in the immune response against pathogens and provide a basis for achieving resistance to diseases in fish breeding.

2.
Fish Shellfish Immunol ; 94: 685-696, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31546038

RESUMO

The S100 family proteins are a group of small acidic polypeptides and have diverse functions in regulating many aspects of physiological processes. They are structurally conserved and possess two EF-hands which are central for calcium-mediated functions. In this study, 14 S100 cDNA sequences were determined in zebrafish and their genomic organizations confirmed. Re-analyzing the gene synteny of the S100 loci identified two major S100 loci in Chr16 and Chr19 which share remarkable conservation with the S100 locus in human Chr1, suggesting they may have evolved from a single locus during the teleost specific whole genome duplication event. It appears that the homologues of human S100G and S100P have been lost in zebrafish. Expression analysis reveals that S100W, ICN1 and ICN2 are markedly expressed in embryos. Further, the transcripts of S100 genes are relatively abundant in mucosal tissues such as gills and gut. Intraperitoneal injection of poly(I:C) resulted in up-regulation of most S100 genes in the gut and spleen, with highest induction of S100V2 and S100Z detected. In fish challenged with spring viremia of carp virus (SVCV), expression of most S100 family genes was increased in the spleen between day 1 and 7 post infection, with consistent induction seen for the S100A1, S100A10b, S100B, S100ICN1, S100T, S100U, S100V1 and S100Z. Interestingly, intraperitoneal injection of Edwardsiella tarda down-regulated S100 expression in the gut but resulted in induction in the spleen. The results demonstrate that the S100 family genes are differentially modulated by bacterial and viral pathogens in zebrafish.


Assuntos
Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Proteínas S100/genética , Transcriptoma/imunologia , Peixe-Zebra/imunologia , Animais , Edwardsiella tarda/fisiologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/veterinária , Proteínas de Peixes/química , Proteínas de Peixes/metabolismo , Poli I-C/farmacologia , Rhabdoviridae/fisiologia , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária , Proteínas S100/química , Proteínas S100/metabolismo
3.
Dev Comp Immunol ; 99: 103401, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31145914

RESUMO

The interleukin (IL) -1 family members play an important role in regulating inflammatory responses and their functions are mediated by a group of receptors consisting of immunoglobulin and Toll/IL-1 receptor (TIR) domains. In humans, 10 IL-1Rs are found. In this study, 5 IL-1 receptors including IL-1R3/IL-1RAcP, IL-1R8/SIGIRR, IL-1R9a/IL-1RAcPL1a, IL-1R9b/IL-1RAcPL1b and IL-1R10/IL-1RAcPL2 were identified in grass carp (Ctenopharyngodon idella). Phylogenetic analysis reveals that the IL-1R9a/IL-1RAcPL1a and IL-1R9b/IL-1RAcPL1b share significantly high sequence similarity and are believed to have been duplicated from the same gene prior to the radiation of teleosts. Further, these two receptors closely relate to the IL-1R10/IL-1RAcPL2, suggesting that they may have evolved from a common ancestor. The IL-1R3/IL-1RAcP, IL-1R9a/IL-1RAcPL1a, IL-1R9b/IL-1RAcPL1b and IL-1R10/IL-1RAcPL2 are highly expressed in the brain. Stimulation of primary spleen leucocytes by LPS and intraperitoneal injection of fish with poly (I:C) or bacterial infection results in significant increases of IL-1R3/IL-1RAcP expression. Interestingly, the IL-1R8/SIGIRR and IL-1R10/IL-1RAcPL2 showed similar expression patterns.


Assuntos
Carpas/classificação , Carpas/imunologia , Proteínas de Peixes/genética , Regulação da Expressão Gênica/imunologia , Filogenia , Receptores de Interleucina-1/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Carpas/genética , Células Cultivadas , Evolução Molecular , Proteínas de Peixes/química , Proteínas de Peixes/imunologia , Duplicação Gênica , Expressão Gênica , Imunidade Inata/genética , Receptores de Interleucina-1/química , Receptores de Interleucina-1/metabolismo , Alinhamento de Sequência , Distribuição Tecidual
4.
Fish Shellfish Immunol ; 92: 91-100, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31146007

RESUMO

Interleukin (IL) 34 plays an important role in regulating macrophage functions and inflammation process. IL-34 homologues have recently been discovered in fish but the functions have not been studied. In this study, an IL-34 homologue was identified in grass carp Ctenopharyngodon idella and its bioactivities were investigated. The grass carp IL-34 was constitutively expressed in tissues, with the highest expression detected in spleen. It could be up-regulated in spleen after infection with F. cloumnare and grass carp reovirus II, and in primary head kidney leucocytes by recombinant IL-4/13B. The recombinant IL-34 produced in bacteria and HEK293T cells showed stimulatory effect on the expression of IL-1ß, IL-6 and IL-8 but inhibited expression of IL-10 and TGF-ß1 in primary head kidney macrophages. The results demonstrate that IL-34 is a proinflammatory cytokine in grass carp.


Assuntos
Carpas/genética , Carpas/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Interleucinas/genética , Interleucinas/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Infecções por Flavobacteriaceae/imunologia , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/fisiologia , Perfilação da Expressão Gênica/veterinária , Células HEK293 , Humanos , Interleucinas/química , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Reoviridae/fisiologia , Infecções por Reoviridae/imunologia , Infecções por Reoviridae/veterinária , Alinhamento de Sequência/veterinária
5.
Int J Biol Macromol ; 132: 1024-1030, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30959132

RESUMO

ADPs-1a and ADPs-3a were two kinds of pure polysaccharide in Angelica dahurica. The immunomodulatory effects of ADPs-1a and ADPs-3a were assayed on phagocytosis, nitric oxide (NO) and cytokines of RAW264.7 cells, and the mechanism was investigated through NF-κB and MAPKs signaling pathway. RAW264.7 cells were stimulated by different concentrations of ADPs-1a and ADPs-3a with LPS (1 µg/mL) as positive control. The results showed that ADPs-1a and ADPs-3a could significantly enhance the phagocytic activity of RAW264.7 cells, and enhance the ability of RAW264.7 cells to release NO, TNF-α and IL-6 in a concentration-dependent manner. At the same time, ADPs-1a and ADPs-3a could significantly up-regulate the mRNA expression of iNOS, TNF-α, IL-6 and the phosphorylation level of p65, p38, ERK, JNK proteins. The immunomodulatory mechanism of ADPs-1a and ADPs-3a on macrophages was related to the up-regulation of phosphorylation of MAPKs and NF-kB.


Assuntos
Angelica/química , Fatores Imunológicos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Polissacarídeos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Interleucina-6/genética , Camundongos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/genética , Fagocitose/efeitos dos fármacos , Células RAW 264.7 , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/genética
6.
Neural Regen Res ; 14(5): 913-920, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30688278

RESUMO

Many studies have shown that (5R)-5-hydroxytriptolide is the optimal modified analogue of triptolide, possessing comparable immunosuppressive activity but much lower cytotoxicity than triptolide. Whether (5R)-5-hydroxytriptolide has preventive effects on neuroinflammation is unclear. This study was designed to pretreat primary astrocytes from the brains of neonatal Sprague-Dawley rats with 20, 100 and 500 nM (5R)-5-hydroxytriptolide for 1 hour before establishing an in vitro neuroinflammation model with 1.0 µg/mL lipopolysaccharide for 24 hours. The generation of nitric oxide was detected by Griess reagents. Astrocyte marker glial fibrillary acidic protein was measured by immunohistochemical staining. The levels of tumor necrosis factor-α and interleukin-1ß in the culture supernatant were assayed by enzyme linked immunosorbent assay. Nuclear factor-κB/p65 expression was examined by immunofluorescence staining. The phosphorylation of inhibitor of nuclear factor IκB-α and the location of nuclear factor-κB/P65 were determined using western blot assay. Our data revealed that (5R)-5-hydroxytriptolide inhibited the generation of nitric oxide, tumor necrosis factor-α and interleukin-1ß from primary astrocytes activated by lipopolysaccharide, decreased the positive reaction intensity of glial fibrillary acidic protein, reduced the expression of tumor necrosis factor alpha and interleukin-1ß in culture supernatant, inhibited the phosphorylation of IκB-α and the translocation of nuclear factor-κB/P65 to the nucleus. These results have confirmed that (5R)-5-hydroxytriptolide inhibits lipopolysaccharide-induced glial inflammatory response and provides cytological experimental data for (5R)-5-hydroxytriptolide in the treatment of neurodegenerative diseases.

7.
ChemSusChem ; 12(10): 2055-2082, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-30664329

RESUMO

Solid sorbents are considered to be promising materials for carbon dioxide capture. In recent years, many studies have focused on the use of solid waste as carbon dioxide sorbents. The use of waste resources as carbon dioxide sorbents not only leads to the development of relatively low-cost materials, but also eliminates waste simultaneously. Different types of waste materials from biomass, industrial waste, household waste, and so forth were used as carbon dioxide sorbents with sufficient carbon dioxide capture capacities. Herein, progress on the development of carbon dioxide sorbents produced from waste materials is reviewed and covers key factors, such as the type of waste, preparation method, further modification method, carbon dioxide sorption performance, and kinetics studies. In addition, a new research direction for further study is proposed. It is hoped that this critical review will not merely sum up the major research directions in this field, but also provide significant suggestions for future work.

8.
Nanotechnology ; 29(30): 305601, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-29723159

RESUMO

Graphene fibers are promising candidates in portable and wearable electronics due to their tiny volume, flexibility and wearability. Here, we successfully synthesized macroscopic graphene composite fibers via a two-step process, i.e. first electrospinning and then chemical vapor deposition (CVD). Briefly, the well-dispersed PAN nanofibers were sprayed onto the copper surface in an electrified thin liquid jet by electrospinning. Subsequently, CVD growth process induced the formation of graphene films using a PAN-solid source of carbon and a copper catalyst. Finally, crumpled and macroscopic graphene composite fibers were obtained from carbon nanofiber/graphene composite webs by self-assembly process in the deionized water. Temperature-dependent conduct behavior reveals that electron transport of the graphene composite fibers belongs to hopping mechanism and the typical electrical conductivity reaches 4.59 × 103 S m-1. These results demonstrated that the graphene composite fibers are promising for the next-generation flexible and wearable electronics.

9.
Mol Immunol ; 97: 109-116, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29626796

RESUMO

The CD8αα homodimer structures of endotherms demonstrate that despite distinct diversity at the amino acid sequence level, a few conserved key amino acids ensure common structural features. The structure of CD8αα in ancient ectotherms, such as lower bony fish, remains unclear. In this study, the high-resolution structure of the grass carp (Ctenopharyngodon idella) CD8αα (Ctid-CD8αα) homodimer was determined using the single-wavelength anomalous diffraction (SAD) method. The structure of Ctid-CD8αα shows distinct differences from the known CD8αα structures of endotherms, including a distinct topological structure with shorter back ß sheets. The configuration and distribution of the hydrophobic core are different from those in endotherms. Interestingly, mutation of the key amino acid F32S, which is very common in fish and lies in the CDR loop region, leads to the absence of the typical cavity that binds to an epitope-MHC I (p/MHC I) in endotherms, yet Ctid-CD8αα can still specifically bind the grass carp peptide-Ctid-UAA-ß2m (p/UAA-ß2m). Our results indicate that during the evolutionary process, CD8αα has undergone dramatic changes that affect its dimeric structure and may use a new strategy to interact with p/MHC I.


Assuntos
Antígenos CD8/química , Antígenos CD8/genética , Carpas/genética , Evolução Molecular , Sequência de Aminoácidos , Animais , Antígenos CD8/metabolismo , Cristalografia por Raios X , Modelos Moleculares , Conformação Proteica , Multimerização Proteica/genética , Análise de Sequência de Proteína
10.
Food Chem Toxicol ; 119: 326-333, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29496530

RESUMO

Flowers of Malus halliana (M. halliana) Koehne have been used as a Chinese traditional medicine to treat metrorrhagia and in our study, its chemical composition and anticoagulant effect were investigated. Five compounds were isolated and identified from M. halliana flowers, including limocitrin-3-O-glucoside (1), baohuoside Ⅱ (2), kaempferol-3-O-α-L-furan arabinoside (3), phloretin-4'-O-glycosidase (4) and afzeloside (5). Compound 1-3 were isolated for the first time from this genus. The anticoagulant effect of the compounds and extracts of M. halliana flowers were evaluated by APTT, PT, TT and FIB on plasma of rabbit in vitro. The results indicated that several fractions of M. halliana flowers and compounds 2-5 exhibited anticoagulant activity in vitro. Subsequently, afzeloside (5), the abundant component in M. halliana flowers, was investigated further for its antithrombotic effect in vivo and its antithrombotic mechanisms were evaluated on rats acute blood-stasis model. The antithrombotic effect was evaluated by WBV, PV, HCT, ESR, APTT, PT, TT, FIB, 6-keto-PGF1α, TXB2, ET-1 and eNOS in vivo. Afzeloside demonstrated inhibitory effect of thrombus formation, and its underlying antithrombotic mechanism was found to be related to the regulation of vascular endothelium active substance, activating blood flow and anticoagulant effect. Hence, we postulate that flavonoids may be the active ingredients of the plant.


Assuntos
Antitrombinas/isolamento & purificação , Antitrombinas/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Flores/química , Malus/química , Alprostadil/análogos & derivados , Alprostadil/análise , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cromatografia Líquida , Endotelina-1/análise , Testes Hematológicos , Masculino , Óxido Nítrico Sintase Tipo III/análise , Espectroscopia de Prótons por Ressonância Magnética , Ratos Sprague-Dawley , Espectrofotometria Ultravioleta , Tromboxano B2/análise
11.
J Nanosci Nanotechnol ; 18(4): 2956-2964, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442980

RESUMO

In this paper, the influence of charge compensating anions of Layered double hydroxides (LDHs) in the LDH-NS/GO nanohybrid for carbon dioxide capture was systematically investigated. The four kinds of different charge compensating anion intercalated LDH were exfoliated and the LDH and Graphene oxide (GO) nanohybrids were synthesized by "exfoliation-self-assembly" method. In this contribution, the CO2 capture capacity of LDH was improved by introducing of GO. And the calcination and adsorption conditions were tested, which proved that the LDH-NS/GO nanohybrids can be used in a wide temperature range for carbon dioxide capture, and the appropriate calcination temperature is 400 °C. Furthermore, the LDH-NS/GO nanohybrids also have a good multiple adsorption/desorption stability, which is vital for practical application.

12.
J Virol ; 92(6)2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29263258

RESUMO

Feline immunodeficiency virus (FIV) infection in domestic cats is the smallest usable natural model for lentiviral infection studies. FLA-E*01801 was applied to FIV AIDS vaccine research. We determined the crystal structure of FLA-E*01801 complexed with a peptide derived from FIV (gag positions 40 to 48; RMANVSTGR [RMA9]). The A pocket of the FLA-E*01801 complex plays a valuable restrictive role in peptide binding. Mutation experiments and circular-dichroism (CD) spectroscopy revealed that peptides with Asp at the first position (P1) could not bind to FLA-E*01801. The crystal structure and in vitro refolding of the mutant FLA-E*01801 complex demonstrated that Glu63 and Trp167 in the A pocket play important roles in restricting P1D. The B pocket of the FLA-E*01801 complex accommodates M/T/A/V/I/L/S residues, whereas the negatively charged F pocket prefers R/K residues. Based on the peptide binding motif, 125 FLA-E*01801-restricted FIV nonapeptides (San Diego isolate) were identified. Our results provide the structural basis for peptide presentation by the FLA-E*01801 molecule, especially A pocket restriction on peptide binding, and identify the potential cytotoxic T lymphocyte (CTL) epitope peptides of FIV presented by FLA-E*01801. These results will benefit both the reasonable design of FLA-E*01801-restricted CTL epitopes and the further development of the AIDS vaccine.IMPORTANCE Feline immunodeficiency virus (FIV) is a viral pathogen in cats, and this infection is the smallest usable natural model for lentivirus infection studies. To examine how FLA I presents FIV epitope peptides, we crystallized and solved the first classic feline major histocompatibility complex class I (MHC-I) molecular structure. Surprisingly, pocket A restricts peptide binding. Trp167 blocks the left side of pocket A, causing P1D to conflict with Glu63 We also identified the FLA-E*01801 binding motif X (except D)-(M/T/A/V/I/L/S)-X-X-X-X-X-X-(R/K) based on structural and biochemical experiments. We identified 125 FLA-E*01801-restricted nonapeptides from FIV. These results are valuable for developing peptide-based FIV and human immunodeficiency virus (HIV) vaccines and for studying how MHC-I molecules present peptides.


Assuntos
Produtos do Gene gag/química , Antígenos de Histocompatibilidade Classe I/química , Vírus da Imunodeficiência Felina/química , Peptídeos/química , Vacinas contra a AIDS/química , Vacinas contra a AIDS/imunologia , Motivos de Aminoácidos , Animais , Apresentação do Antígeno , Sítios de Ligação , Gatos , Cristalografia por Raios X , Produtos do Gene gag/imunologia , HIV-1/química , HIV-1/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Vírus da Imunodeficiência Felina/imunologia , Peptídeos/imunologia
13.
J Immunol ; 199(10): 3668-3678, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-29055007

RESUMO

MHC molecules evolved with the descent of jawed fishes some 350-400 million years ago. However, very little is known about the structural features of primitive MHC molecules. To gain insight into these features, we focused on the MHC class I Ctid-UAA of the evolutionarily distant grass carp (Ctenopharyngodon idella). The Ctid-UAA H chain and ß2-microglobulin (Ctid-ß2m) were refolded in vitro in the presence of peptides from viruses that infect carp. The resulting peptide-Ctid-UAA (p/Ctid-UAA) structures revealed the classical MHC class I topology with structural variations. In comparison with known mammalian and chicken peptide-MHC class I (p/MHC I) complexes, p/Ctid-UAA structure revealed several distinct features. Notably, 1) although the peptide ligand conventionally occupied all six pockets (A-F) of the Ag-binding site, the binding mode of the P3 side chain to pocket D was not observed in other p/MHC I structures; 2) the AB loop between ß strands of the α1 domain of p/Ctid-UAA complex comes into contact with Ctid-ß2m, an interaction observed only in chicken p/BF2*2101-ß2m complex; and 3) the CD loop of the α3 domain, which in mammals forms a contact with CD8, has a unique position in p/Ctid-UAA that does not superimpose with the structures of any known p/MHC I complexes, suggesting that the p/Ctid-UAA to Ctid-CD8 binding mode may be distinct. This demonstration of the structure of a bony fish MHC class I molecule provides a foundation for understanding the evolution of primitive class I molecules, how they present peptide Ags, and how they might control T cell responses.


Assuntos
Antígenos/metabolismo , Carpas/imunologia , Proteínas de Peixes/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Linfócitos T/imunologia , Animais , Apresentação do Antígeno , Evolução Biológica , Galinhas , Clonagem Molecular , Sequência Conservada/genética , Proteínas de Peixes/genética , Antígenos de Histocompatibilidade Classe I/genética , Imunidade Celular , Mamíferos , Ligação Proteica , Conformação Proteica , Engenharia de Proteínas , Homologia de Sequência , Relação Estrutura-Atividade
14.
Sci Adv ; 3(9): e1701186, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28913429

RESUMO

Organic thin-film transistors (OTFTs) with high mobility and low contact resistance have been actively pursued as building blocks for low-cost organic electronics. In conventional solution-processed or vacuum-deposited OTFTs, due to interfacial defects and traps, the organic film has to reach a certain thickness for efficient charge transport. Using an ultimate monolayer of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) molecules as an OTFT channel, we demonstrate remarkable electrical characteristics, including intrinsic hole mobility over 30 cm2/Vs, Ohmic contact with 100 Ω · cm resistance, and band-like transport down to 150 K. Compared to conventional OTFTs, the main advantage of a monolayer channel is the direct, nondisruptive contact between the charge transport layer and metal leads, a feature that is vital for achieving low contact resistance and current saturation voltage. On the other hand, bilayer and thicker C8-BTBT OTFTs exhibit strong Schottky contact and much higher contact resistance but can be improved by inserting a doped graphene buffer layer. Our results suggest that highly crystalline molecular monolayers are promising form factors to build high-performance OTFTs and investigate device physics. They also allow us to precisely model how the molecular packing changes the transport and contact properties.

15.
J Virol ; 91(14)2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28490583

RESUMO

A single dominantly expressed allele of major histocompatibility complex class I (MHC I) may be responsible for the duck's high tolerance to highly pathogenic influenza A virus (HP-IAV) compared to the chicken's lower tolerance. In this study, the crystal structures of duck MHC I (Anpl-UAA*01) and duck ß2-microglobulin (ß2m) with two peptides from the H5N1 strains were determined. Two remarkable features were found to distinguish the Anpl-UAA*01 complex from other known MHC I structures. A disulfide bond formed by Cys95 and Cys112 and connecting the ß5 and ß6 sheets at the bottom of peptide binding groove (PBG) in Anpl-UAA*01 complex, which can enhance IAV peptide binding, was identified. Moreover, the interface area between duck MHC I and ß2m was found to be larger than in other species. In addition, the two IAV peptides that display distinctive conformations in the PBG, B, and F pockets act as the primary anchor sites. Thirty-one IAV peptides were used to verify the peptide binding motif of Anpl-UAA*01, and the results confirmed that the peptide binding motif is similar to that of HLA-A*0201. Based on this motif, approximately 600 peptides from the IAV strains were partially verified as the candidate epitope peptides for Anpl-UAA*01, which is a far greater number than those for chicken BF2*2101 and BF2*0401 molecules. Extensive IAV peptide binding should allow for ducks with this Anpl-UAA*01 haplotype to resist IAV infection.IMPORTANCE Ducks are natural reservoirs of influenza A virus (IAV) and are more resistant to the IAV than chickens. Both ducks and chickens express only one dominant MHC I locus providing resistance to the virus. To investigate how MHC I provides IAV resistance, crystal structures of the dominantly expressed duck MHC class I (pAnpl-UAA*01) with two IAV peptides were determined. A disulfide bond was identified in the peptide binding groove that can facilitate Anpl-UAA*01 binding to IAV peptides. Anpl-UAA*01 has a much wider recognition spectrum of IAV epitope peptides than do chickens. The IAV peptides bound by Anpl-UAA*01 display distinctive conformations that can help induce an extensive cytotoxic T lymphocyte (CTL) response. In addition, the interface area between the duck MHC I and ß2m is larger than in other species. These results indicate that HP-IAV resistance in ducks is due to extensive CTL responses induced by MHC I.


Assuntos
Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Virus da Influenza A Subtipo H5N1/imunologia , Influenza Aviária/imunologia , Linfócitos T Citotóxicos/imunologia , Microglobulina beta-2/química , Microglobulina beta-2/metabolismo , Animais , Antígenos Virais/metabolismo , Cristalografia por Raios X , Patos , Modelos Moleculares , Oligopeptídeos/metabolismo , Ligação Proteica , Conformação Proteica
16.
Sci Rep ; 7: 42862, 2017 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-28205630

RESUMO

Pt/K2CO3/MgAlOx-reduced graphene oxide (Pt/K/MgAlOx-rGO) hybrids were synthesized, characterized and tested as a promising NOx storage and reduction (NSR) catalyst. Mg-Al layered double hydroxides (LDHs) were grown on rGO via in situ hydrothermal crystallization. The structure and morphology of samples were thoroughly characterized using various techniques. Isothermal NOx adsorption tests indicated that MgAlOx-rGO hybrid exhibited better NOx trapping performance than MgAlOx, from 0.44 to 0.61 mmol · g-1, which can be attributed to the enhanced particle dispersion and stabilization. In addition, a series of MgAlOx-rGO loaded with 2 wt% Pt and different loadings (5, 10, 15, and 20 wt%) of K2CO3 (denoted as Pt/K/MgAlOx-rGO) were obtained by sequential impregnation. The influence of 5% H2O on the NOx storage capacity of MgAlOx-rGO loaded with 2 wt% Pt and 10% K2CO3 (2Pt/10 K/MgAlOx-rGO) catalyst was also evaluated. In all, the 2Pt/10 K/MgAlOx-rGO catalyst not only exhibited high thermal stability and NOx storage capacity of 1.12 mmol · g-1, but also possessed excellent H2O resistance and lean-rich cycling performance, with an overall 78.4% of NOx removal. This work provided a new scheme for the preparation of highly dispersed MgAlOx-rGO hybrid based NSR catalysts.

17.
ACS Appl Mater Interfaces ; 9(7): 6644-6651, 2017 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-28150931

RESUMO

Ultraflexible transparent film heaters have been fabricated by embedding conductive silver (Ag) nanowires into a thin poly(vinyl alcohol) film (AgNW/PVA). A cold-pressing method was used to rationally adjust the sheet resistance of the composite films and thus the heating powers of the AgNW/PVA film heaters at certain biases. The film heaters have a favorable optical transmittance (93.1% at 26 Ω/sq) and an outstanding mechanical flexibility (no visible change in sheet resistance after 10 000 bending cycles and at a radius of curvature ≤1 mm). The film heaters have an environmental endurance, and there is no significant performance degradation after being kept at high temperature (80 °C) and high humidity (45 °C, 80% humidity) for half a year. The efficient Joule heating can increase the temperature of the film heaters (20 Ω/sq) to 74 °C in ∼20 s at a bias of 5 V. The fast-heating characteristics at low voltages (a few volts) associated with its transparent and flexibility properties make the poly(dimethylsiloxane)/AgNW/PVA composite film a potential candidate in medical thermotherapy pads.


Assuntos
Nanofios , Condutividade Elétrica , Dureza , Temperatura Alta , Hipertermia Induzida , Membranas Artificiais , Oxirredução , Prata , Propriedades de Superfície
18.
J Biomed Nanotechnol ; 12(5): 922-33, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27305815

RESUMO

The performance of delaminated Mg-Al-lactate and Mg-Al-acetate layered double hydroxides (LDHs) nanosheets (Mg-Al-lactate-NS, Mg-Al-acetate-NS) as efficient vectors for DNA adsorption and delivery to 293T cells was investigated. Mg-Al-lactate and Mg-Al-acetate LDHs were delaminated into single layers in water and were characterized using XRD, SEM, TEM, and Zeta potential measurements. The salmon sperm DNA adsorption capacity of Mg-Al-lactate-NS and Mg-Al-acetate-NS were evaluated by varying the adsorbent dosage and contacting time, which suggested that Mg-Al-lactate-NS had much higher adsorption capacity (649.6 µg mg-1) than that of Mg-Al-acetate-NS (340.0 µg mg(-1)). XRD analysis indicated that after DNA adsorption the Mg-Al-lactate-NS-DNA bio-inorganic nanohybrid still stayed in an exfoliated form. Due to the difficulty in separating the Mg-Al-lactate-NS-DNA from solution, electrophoresis analysis was also applied to detect the free DNA in solution after adsorption. Cytotoxicity studies using 293T cells verified that Mg-Al-lactate-NS was less toxic than Mg-Al-acetate-NS as a smaller dose of this LDH was needed to deliver the same amount of salmon DNA to 293T cells. Cellular uptake and confocal imaging studies demonstrated that Mg-Al-lactate-NS was successful in transfection of ssDNA-FITC into 293T cells. However, the FITC-coupled single strand DNA was failed to be internalized into these cells. The excellent DNA adsorption and delivery capacities indicate that delaminated Mg-Al-lactate LDHs nanosheets are a better DNA vector than bulk phase LDH.


Assuntos
DNA/administração & dosagem , Técnicas de Transferência de Genes , Vetores Genéticos/metabolismo , Hidróxidos/química , Nanopartículas/química , Adsorção , Alumínio/química , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Eletroforese em Gel de Ágar , Endocitose/efeitos dos fármacos , Citometria de Fluxo , Humanos , Hidróxidos/toxicidade , Cinética , Ácido Láctico/química , Magnésio/química , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Fatores de Tempo , Difração de Raios X
19.
Sci Rep ; 6: 26738, 2016 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-27221055

RESUMO

Here we report a powerful method that facilitates the transport of biologically active materials across the cell wall barrier in plant cells. Positively charged delaminated layered double hydroxide lactate nanosheets (LDH-lactate-NS) with a 0.5‒2 nm thickness and 30‒60 nm diameter exhibit a high adsorptive capacity for negatively charged biomolecules, including fluorescent dyes such as tetramethyl rhodamine isothiocyanate (TRITC), fluorescein isothiocyanate isomer I(FITC) and DNA molecules, forming neutral LDH-nanosheet conjugates. These neutral conjugates can shuttle the bound fluorescent dye into the cytosol of intact plant cell very efficiently. Furthermore, typical inhibitors of endocytosis and low temperature incubation did not prevent LDH-lactate-NS internalization, suggesting that LDH-lactate-NS penetrated the plasma membrane via non-endocytic pathways, which will widen the applicability to a variety of plant cells. Moreover, the absence of unwanted side effects in our cytological studies, and the nuclear localization of ssDNA-FITC suggest that nano-LDHs have potential application as a novel gene carrier to plants.


Assuntos
Portadores de Fármacos , Lactatos , Nanopartículas/química , Células Vegetais/metabolismo , Tabaco/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Lactatos/química , Lactatos/farmacocinética , Lactatos/farmacologia , Tabaco/citologia
20.
Curr Alzheimer Res ; 13(3): 288-96, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26906357

RESUMO

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease characterized by aggregation of amyloid-ß (Aß) peptide in the hippocampus and cortex of brain. Neuroinflammation is considered a driving force of the progression of cognitive decline in AD. During the neuroinflammatory process, activated astrocytes and microglia induced by Aß peptide produce pro-inflammatory factors and neurotoxins, which promote neurodegeneration in AD brain, eventually dementia. Thus, the suppression of glial over-activation in AD brain might result in therapeutic effect. Triptolide, a natural compound extracted from the Chinese medicinal herb Tripterygium wilfordii Hook F., has shown anti-inflammatory effects. Whether triptolide exhibits preventive effects on AD-like pathology via anti-inflammatory action is unclear. The present study showed that intraperitoneal injection of triptolide (20 µg/kg) for 15 weeks markedly alleviated deficits in learning and memory, and prevented Aß accumulation in the brain of AD transgenic mice (APP/PS1 mice). These results were accompanied by reduction in glial activation and contents of pro-inflammatory factors in the brain of APP/PS1 mice treated by triptolide compared to saline-treated APP/PS1 mice. In addition, we observed that the Mitogen-activated protein kinases (MAPKs, including p38, ERK and JNK) phosphorylation was also suppressed by treatment of triptolide in the brain of APP/PS1 mice. Taken together, our study suggests that molecular mechanisms underlying the therapeutic effects of triptolide on the AD model might involve inhibition of the neuroinflammation by suppressing MAPKs activity.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Diterpenos/farmacologia , Mediadores da Inflamação/antagonistas & inibidores , Transtornos da Memória/tratamento farmacológico , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Fenantrenos/farmacologia , Agregação Patológica de Proteínas/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Diterpenos/uso terapêutico , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Compostos de Epóxi/farmacologia , Compostos de Epóxi/uso terapêutico , Feminino , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Mediadores da Inflamação/metabolismo , Transtornos da Memória/genética , Transtornos da Memória/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fenantrenos/uso terapêutico , Presenilina-1/genética , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/metabolismo
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