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1.
Small ; : e2306203, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38128031

RESUMO

Semiconductor core/shell quantum dots (QDs) are considered promising building blocks to fabricate photoelectrochemical (PEC) cells for the direct conversion of solar energy into hydrogen (H2 ). However, the lattice mismatch between core and shell in such QDs results in undesirable defects and severe carrier recombination, limiting photo-induced carrier separation/transfer and solar-to-fuel conversion efficiency. Here, an interface engineering approach is explored to minimize the core-shell lattice mismatch in CdS/CdSex S1-x (x = 0.09-1) core/shell QDs (g-CSG). As a proof-of-concept, PEC cells based on g-CSG QDs yield a remarkable photocurrent density of 13.1 mA cm-2 under AM 1.5 G one-sun illumination (100 mW cm-2 ), which is ≈54.1% and ≈33.7% higher compared to that in CdS/CdSe0.5 S0.5 (g-CSA) and CdS/CdSe QDs (g-CS), respectively. Theoretical calculations and carrier dynamics confirm more efficient carrier separation and charge transfer rate in g-CSG QDs with respect to g-CSA and g-CS QDs. These results are attributed to the minimization of the core-shell lattice mismatch by the cascade gradient shell in g-CSG QDs, which modifies carrier confinement potential and reduces interfacial defects. This work provides fundamental insights into the interface engineering of core/shell QDs and may open up new avenues to boost the performance of PEC cells for H2 evolution and other QDs-based optoelectronic devices.

2.
Int J Genomics ; 2023: 8766311, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965055

RESUMO

Background: Lung cancer is considered to be the second most aggressive and rapidly fatal cancer after breast cancer. Necroptosis, a novel discovered pattern of cell death, is mediated by Receptor-interacting serine/threonine-protein kinase 1 (RIPK1), Receptor-interacting serine/threonine-protein kinase 3 (RIPK3), and Mixed Lineage Kinase Domain Like Pseudokinase (MLKL). Methods: For the purpose of developing a prognostic model, Least absolute shrinkage and selection operator (LASSO) Cox regression analysis was conducted. Using Pearson's correlation analysis, we evaluated the correlation between necroptosis-related markers and tumor immune infiltration. A bioinformatics analysis was conducted to construct a necroptosis-related regulatory axis. Results: There was a downregulation of most of necroptosis-related genes in lung adenocarcinoma (LUAD) versus lung tissues but an increase in PGAM5, HMGB1, TRAF2, EZH2 levels. We also summarized the Single Nucleotide Variant (SNV) and copy number variation (CNV) of necroptosis-related genes in LUAD. Consensus clustering identified two clusters in LUAD with distinct immune cell infiltration and ESTIMATEScore. Genes related to necroptosis were associated with necroptosis, Tumor necrosis factor (TNF) signaling pathway, and apoptosis according to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Four prognostic genes (ALDH2, HMGB1, NDRG2, TLR2) were combined to develop a prognostic gene signature for LUAD patients, which was highly accurate in predicting prognosis. Univariate and multivariate analysis identified HMGB1, pT stage, and pN stage as independent factors impacting on LUAD patients' prognosis. A significant correlation was found between the level of TLR2 and NDRG2 and clinical stage, immunity infiltration, and drug resistance. Additionally, the progression of LUAD might be regulated by lncRNA C5orf64/miR-582-5p/NDRG2/TLR2. Conclusion: The current bioinformatics analysis identified a necroptosis-related prognostic signature for LUAD and their relation to immunity infiltration. This result requires further investigation.

3.
Front Immunol ; 13: 928374, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389825

RESUMO

HLA-DR3 (DR3) is one of the dominant HLA-DR alleles associated with systemic lupus erythematosus (SLE) susceptibility. Our previous studies showed multiple intramolecular DR3 restricted T cell epitopes in the Smith D (SmD) protein, from which we generated a non-homologous, bacterial epitope mimics library. From this library we identified ABC247-261 Mimic as one new DR3 restricted bacterial T cell epitope from the ABC transporter ATP-binding protein in Clostridium tetani. It activated and induced autoreactive SmD66-80-specific T cells and induced autoantibodies to lupus-related autoantigens in vivo. Compared to healthy donors, SLE patients have a greater percentage of cross-reactive T cells to ABC247-261 Mimic and SmD66-80. In addition, we analyzed the ability of single DR3 restricted Tetanus toxoid (TT) T cell epitopes to induce autoimmune T cells. We found that the immunodominant TT epitope TT826-845 stimulated SmD66-80 reactive T cells but failed to induce persistent anti-SmD autoantibodies compared to the ABC247-261 Mimic. Thus, exposure to the ABC247-261 Mimic epitope may contribute to autoimmunity in susceptible DR3 individuals.


Assuntos
Antígeno HLA-DR3 , Lúpus Eritematoso Sistêmico , Humanos , Autoantígenos , Clostridium tetani , Epitopos de Linfócito T , Linfócitos T , Autoanticorpos
4.
Adv Sci (Weinh) ; 9(36): e2203527, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36316226

RESUMO

The continuous deterioration of the environment due to extensive industrialization and urbanization has raised the requirement to devise high-performance environmental remediation technologies. Membrane technologies, primarily based on conventional polymers, are the most commercialized air, water, solid, and radiation-based environmental remediation strategies. Low stability at high temperatures, swelling in organic contaminants, and poor selectivity are the fundamental issues associated with polymeric membranes restricting their scalable viability. Polymer-metal-carbides and nitrides (MXenes) hybrid membranes possess remarkable physicochemical attributes, including strong mechanical endurance, high mechanical flexibility, superior adsorptive behavior, and selective permeability, due to multi-interactions between polymers and MXene's surface functionalities. This review articulates the state-of-the-art MXene-polymer hybrid membranes, emphasizing its fabrication routes, enhanced physicochemical properties, and improved adsorptive behavior. It comprehensively summarizes the utilization of MXene-polymer hybrid membranes for environmental remediation applications, including water purification, desalination, ion-separation, gas separation and detection, containment adsorption, and electromagnetic and nuclear radiation shielding. Furthermore, the review highlights the associated bottlenecks of MXene-Polymer hybrid-membranes and its possible alternate solutions to meet industrial requirements. Discussed are opportunities and prospects related to MXene-polymer membrane to devise intelligent and next-generation environmental remediation strategies with the integration of modern age technologies of internet-of-things, artificial intelligence, machine-learning, 5G-communication and cloud-computing are elucidated.


Assuntos
Inteligência Artificial , Recuperação e Remediação Ambiental , Aprendizado de Máquina , Polímeros
5.
ACS Appl Mater Interfaces ; 14(27): 30969-30978, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35763305

RESUMO

The electrocatalytic nitrate conversion of ammonia at ambient conditions provides not only a solution for restoring the imbalance in the global nitrogen cycle but also a sustainable alternative for the Haber-Bosch process. However, large-scale and efficient application of electrocatalytic denitrification has been limited by the lack of active catalysts with a high selectivity of nitrate reduction to N2. In this work, we present a one-step solution processed synthetic strategy at low temperature to prepare carbon-nanobelts-supported uniform Cu and Pd nanoclusters. It is found that Cu catalyzed the formation of carbon nanobelts. The prepared samples were used for the green synthesis of ammonia from nitrate by electrocatalysis. For the nitrate reduction reaction (NO3RR), Cu-Pd/C nanobelts show higher activity than Cu/C nanobelts, achieving a high yield of ammonia of 220.8 µg mgcat-1 h-1 with a Faradaic efficiency (FE) of 62.3% at -0.4 V vs RHE (reversible hydrogen electrode), while for the nitrite reduction reaction (NO2RR), a high FE of 95% at -0.2 V vs RHE can be obtained for Cu/C nanobelts with the yield of ammonia increased with the negative shift of the applied potentials. Theoretical calculations demonstrated that Pd and Cu are responsible for hydrogen evolution reaction (HER) and NO3RR, respectively.

6.
Ann Rheum Dis ; 81(7): 1006-1012, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35414518

RESUMO

OBJECTIVE: NLRP3 inflammasome regulates T cell responses. This study examined the roles of NLRP3 inflammasome activation in the regulation of T follicular helper (Tfh) cells during humoral response to T dependent antigens and in systemic lupus erythematosus (SLE). METHODS: NLRP3 inflammasome activation of Tfh cells was studied in B6, MRL/lpr and NZM2328 mice and in SLE patients and healthy controls using a fluorescence-labelled caspase-1 inhibitor probe. MCC950, a selective inhibitor of NLRP3, was used to investigate the relation between NLRP3 inflammasome activation and germinal centre (GC) reaction, Ab responses to immunisation, and autoantibody production. RESULTS: NLRP3 inflammasome activation in Tfh cells after immunisation was identified in B6 mice. MCC950 inhibited humoral responses to sheep red blood cell and NP-CGG with reduction of the GC reaction. B6 mice with lymphoid cell-specific deletion of NLRP3 or Casp1 mounted suboptimal humoral responses with impaired GC formation and defective affinity maturation. In MRL/lpr and NZM2328 mice, inhibition of NLRP3 activation suppressed NLRP3 activated Tfh cell expansion as well as attenuated lupus-like phenotypes. Tfh cells with activated NLRP3 inflammasome exhibited increased expression of molecules for Tfh cell function and differentiation, and had greater ability to activate B cells. In SLE patients, disease activity was positively correlated with an increase in the activated NLRP3+ Tfh population and this population was markedly reduced in response to therapy. CONCLUSIONS: The activation of NLRP3 inflammasome in Tfh cells is an integral part of responses to immunisation. The activated NLRP3+ Tfh population is essential for optimal humoral responses, GC formation and autoimmunity.


Assuntos
Autoimunidade , Lúpus Eritematoso Sistêmico , Proteína 3 que Contém Domínio de Pirina da Família NLR , Células T Auxiliares Foliculares , Animais , Centro Germinativo , Inflamassomos/metabolismo , Camundongos , Camundongos Endogâmicos MRL lpr , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Células T Auxiliares Foliculares/imunologia , Linfócitos T Auxiliares-Indutores
7.
Chem Commun (Camb) ; 57(100): 13752-13755, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34854438

RESUMO

The cobalt, iron co-incorporated Ni(OH)2 multiphase displays superior catalytic activity and stability for multifunctional electrocatalytic oxidation, ascribed to the multiphase synergy, enhanced charge transfer and well-exposed active sites.

8.
Nanomicro Lett ; 13(1): 188, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34482476

RESUMO

A good method of synthesizing Ti3C2Tx (MXene) is critical for ensuring its success in practical applications, e.g., electromagnetic interference shielding, electrochemical energy storage, catalysis, sensors, and biomedicine. The main concerns focus on the moderation of the approach, yield, and product quality. Herein, a modified approach, organic solvent-assisted intercalation and collection, was developed to prepare Ti3C2Tx flakes. The new approach simultaneously solves all the concerns, featuring a low requirement for facility (centrifugation speed < 4000 rpm in whole process), gram-level preparation with remarkable yield (46.3%), a good electrical conductivity (8672 S cm-1), an outstanding capacitive performance (352 F g-1), and easy control over the dimension of Ti3C2Tx flakes (0.47-4.60 µm2). This approach not only gives a superb example for the synthesis of other MXene materials in laboratory, but sheds new light for the future mass production of Ti3C2Tx MXene.

9.
J Colloid Interface Sci ; 596: 89-99, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33838328

RESUMO

Construction of binder-free electrodes with hierarchical core-shell nanostructures is considered to be an effective route to promote the electrochemical performance of supercapacitors. In this work, the porous Ni0.5Mn0.5Co2O4 nanoflowers anchored on nickel foam are utilized as framework for further growing Co3O4 nanowires, resulting in the hierarchical sea urchin-like Ni0.5Mn0.5Co2O4@Co3O4 core-shell microspheres on nickel foam. Owing to the advantages brought by unique porous architecture and synergistic effect of the multi-component composites, the as-prepared electrode exhibits a high specific capacitance (931 F/g at 1 A/g), excellent rate performance (77% capacitance retention at 20 A/g) and outstanding cycle stability (92% retention over 5000 cycles at 5 A/g). Additionally, the assembled Ni0.5Mn0.5Co2O4@Co3O4//AC (activated carbon) asymmetric supercapacitor achieves a high energy density (50 Wh/kg at 750 W/kg) and long durability (88% retention after 5000 cycles).

10.
Small ; 17(10): e2006687, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33506634

RESUMO

An in situ coupling approach is used to fabricate the porous carbon liquid with permanent porosity by directly dispersing hollow carbon nanospheres in polymerized ionic liquids. It is a kind of homogenous and stable type III porous liquid at room temperature. Because of the well-preserved permanent porosity, this unique porous carbon liquid is capable of absorbing the largest quantity of carbon dioxide than the reference PILs and solid carbon liquid, thus, can function as a promising candidate for application in gas storage. More importantly, this approach not only provides an easy method to tune the properties of those specific porous liquids, but also is suitable for fabricating other porous liquid based on varied porous structures (e.g., porous carbon nitride, porous boron nitride, and polymer with intrinsic microporosity), thus paving a viable path for the rational design and synthesis of novel porous liquids with functional properties for specific applications.

11.
Chem Commun (Camb) ; 57(16): 2029-2032, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33506837

RESUMO

Lanthanum-incorporated ß-Ni(OH)2 nanosheets display superior catalytic behavior and stability for urea electro-oxidation, which originates from the optimized electronic structure, the downshift of the d-band center and the increased number of exposed active sites.

12.
Clin Immunol ; 224: 108675, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33482358

RESUMO

Cgnz1 on chromosome 1 mapped into a 1.34 Mb region of chromosome 1 in NZM2328 confers the progression of immune complex (IC)-mediated glomerulonephritis (GN) from acute GN (aGN) to chronic GN (cGN) with severe proteinuria and end stage renal disease in female mice. This genetic locus mediates podocyte susceptibility to IC-mediated damage. Taking advantage of the published observation that Cgnz1 is derived from NZW and that NZW is susceptible to orchitis, epididymitis and vasitis while C57L/J is resistant to these diseases, the possibility that this genetic region also confers germ cells susceptible to damage with aspermatogenesis and sterility in an active experimental autoimmune orchitis (EAO) model was investigated. Male mice from multiple intrachromosome (chromosome 1) recombinant strains were subjected to immunization with a sperm homogenate in CFA with concomitant administration of Bordetella pertussis toxin. There was concordance of the progression from aGN to cGN, severe proteinuria and end stage renal disease with susceptibility of EAO in NZM2328 and its congenic strains with various chromosome 1 genetic intervals introgressed from C57L/J to NZM2328. Both resistant and susceptible strains made comparable anti-testis and anti-sperm Abs. Thus the genetic interval that determines susceptibility to EAO is identical to that of Cgnz1 and mapped to the 1.34 Mb region in chromosone 1. This region likely confers germ cells in the male gonad susceptible to damage by immunologically mediated inflammation. This region has been tentatively renamed Cgnz1/Eaoz1. These observations further emphasize the importance of end organ susceptibility to damage in the pathogenesis of both systemic and organ specific autoimmune diseases.


Assuntos
Doenças Autoimunes/imunologia , Predisposição Genética para Doença , Glomerulonefrite/imunologia , Falência Renal Crônica/imunologia , Orquite/imunologia , Animais , Doenças Autoimunes/etiologia , Doenças Autoimunes/genética , Feminino , Regulação da Expressão Gênica/imunologia , Glomerulonefrite/complicações , Glomerulonefrite/genética , Falência Renal Crônica/complicações , Falência Renal Crônica/genética , Masculino , Camundongos , Orquite/etiologia , Orquite/genética
13.
Pharmgenomics Pers Med ; 13: 645-653, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262635

RESUMO

BACKGROUND: There have been few studies on CYP2C19 genotypes and clopidogrel response associated with ischemic stroke (IS), especially IS complicated by type 2 diabetes mellitus (T2DM). This study aimed to investigate the possible association between CYP2C19 polymorphisms and high on-treatment platelet reactivity (HTPR) in IS patients with T2DM in China. PATIENTS AND METHODS: A total of 426 consecutive IS patients with T2DM were enrolled in this case-control study and they were divided into HTPR group and non-HTPR group according to the ADP-induced platelet inhibition (PIADP) assessed by thromboelastography (TEG). Genotypes were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Various clinical and demographic data were also recorded. The association between CYP2C19 genetic variants and platelet function was assessed. RESULTS: Carriers of CYP2C19*2 heterozygous and mutant homozygous genotypes showed significantly lower PIADP than non-carriers (27.2% vs 38.3%, p < 0.001; 27.41% vs 38.3%, p = 0.012, respectively). Compared with the control group, the CYP2C19*2 A allele was more frequent in the HTPR group (34.51% vs 25.82%, p = 0.002). The carriage of CYP2C19*2 mutant allele was significantly associated with increased risk of HTPR (odds ratio (OR) = 1.94, 95% confidence interval (CI) = 1.32-2.85). There was no significant correlation between CYP2C19*3 or *17 genotypes and HTPR risk. CONCLUSION: CYP2C19*2 mutant allele was associated with attenuated platelet response to clopidogrel and increased risk of HTPR in IS patients with T2DM, suggesting that CYP2C19*2 polymorphism might be an important predictor of HTPR in this high-risk population.

14.
Oncologist ; 25(12): e1900-e1908, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32864805

RESUMO

LESSONS LEARNED: The efficacy of single-agent chemotherapy was not significantly different from that of double-agent chemotherapy in concurrent chemoradiotherapy for inoperable esophageal squamous cell carcinoma. Single-agent concurrent chemoradiotherapy had lower gastrointestinal and hematologic toxicity. Overall survival and progression-free survival were not significantly different between single- and double-agent concurrent chemoradiotherapy. BACKGROUND: This multicenter, randomized, phase II trial aimed to compare the efficacy and safety of single-agent concurrent chemoradiotherapy using the oral fluoropyrimidine S-1 with those of double-agent concurrent chemoradiotherapy using S-1 and cisplatin in patients with inoperable esophageal squamous cell carcinoma. METHODS: Patients with inoperable esophageal squamous cell carcinoma (clinical stages I to III) were randomly allocated to the single-agent group (S-1) or the double-agent group (S-1/cisplatin). The concurrent intensity-modulated radiation therapy plan was similar for both groups: planning target volume 1.8 Gy/f*30-33f and planning gross target volume of 2 Gy/f*30-33f. The primary outcome measure was the endoscopic complete response rate. RESULTS: Of the 105 patients randomized, 89 were assessable. The endoscopic complete response rate was 46.9% (23/49) in the single-agent group and 52.5% (21/40) in double-agent group. The median progression-free survival within a median follow-up of 23 months was 20 and 21 months, respectively. The median overall survival was 26 months and not reached, respectively. Grade 3 hematological toxicities occurred in 4.1% and 27.5% of the patients in the single- and the double-agent group, respectively. CONCLUSION: Single-agent chemotherapy in concurrent chemoradiotherapy for inoperable esophageal squamous cell carcinoma has good efficacy and safety, thus warranting a phase III trial.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Neoplasias de Cabeça e Pescoço , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia , Cisplatino/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Fluoruracila/uso terapêutico , Humanos , Estudos Prospectivos
15.
ACS Nano ; 14(10): 13876-13885, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32965103

RESUMO

The TiO2/Au nanostructure has been acknowledged as one of the most classic visible-light active photocatalysts due to the surface plasmon resonance (SPR) of Au nanoparticles. In many cases, the SPR effect only features weak visible light absorption in conventional TiO2/Au nanostructures. Here, we demonstrate a design of TiO2/Au/TiO2 with a combination of whispering gallery mode (WGM) resonances and SPR for efficient visible-light-driven photocatalysis. Escherichia coli (E. coli) were used as natural reactants as well as a template to construct an E. coli-like TiO2/Au/TiO2 nanostructure. Using numerical simulations, we show that the E. coli-like TiO2 capsule acts as the WGM resonator to interplay with the SPR effect of the Au NPs on TiO2 surface, which leads to a significant increase of visible light absorption and the local field enhancement at the Au-TiO2 interface. Accordingly, with the synergistic effect of WGM and SPR, the E. coli-like TiO2/Au/TiO2 nanostructure exhibits enhanced photocatalytic activity in the visible range. Our work reveals a promising bioapproach to a design highly visible light active plasmonic photocatalyst.


Assuntos
Ouro , Nanopartículas Metálicas , Catálise , Escherichia coli , Titânio
16.
Nanotechnology ; 31(37): 375402, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32480386

RESUMO

Transition metal element doping into semiconducting materials has been a promising method for the preparation of active photocatalysts for the efficient use of solar energy. In this study, we report the facile synthesis of Fe doped SrWO4 nanoparticles by a solvothermal method for photocatalytic nitrogen reduction. The intrinsic bandgap of SrWO4 is greatly narrowed by the Fe-dopant which not only extends the light absorption from UV to visible light range, but also reduces the charge recombination. The narrowed band structure still fulfils the thermodynamic requirements of nitrogen reduction reaction. At optimal doping concentration, Fe doped SrWO4 shows much higher photocatalytic nitrogen fixation performance. The present study provides a route toward the development of active photocatalysts for nitrogen fixation.

17.
Nanoscale Res Lett ; 15(1): 88, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32318893

RESUMO

Using biowastes as precursors for the preparation of value-added nanomaterials is critical to the sustainable development of devices. Lignosulphonates are the by-products of pulp and paper-making industries and usually discarded as wastes. In the present study, lignosulphonate is used as the precursor to prepare hierarchical ordered porous carbon with interconnected pores for the electrochemical energy storage application. The unique molecular structure and properties of lignosulphonate ensure the acquisition of high-quality porous carbon with a controllable pore structure and improved physical properties. As a result, the as-prepared hierarchical order porous carbon show excellent energy storage performance when used to assemble the symmetric supercapacitor, which exhibits high-specific capacitance of 289 F g-1 at a current density of 0.5 A g-1, with the energy density of 40 Wh kg-1 at the power density of 900 W kg-1. The present study provides a promising strategy for the fabrication of high-performance energy storage devices at low cost.

18.
Nanomicro Lett ; 12(1): 71, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-34138318

RESUMO

Chemi-resistive sensors based on hybrid functional materials are promising candidates for gas sensing with high responsivity, good selectivity, fast response/recovery, great stability/repeatability, room-working temperature, low cost, and easy-to-fabricate, for versatile applications. This progress report reviews the advantages and advances of these sensing structures compared with the single constituent, according to five main sensing forms: manipulating/constructing heterojunctions, catalytic reaction, charge transfer, charge carrier transport, molecular binding/sieving, and their combinations. Promises and challenges of the advances of each form are presented and discussed. Critical thinking and ideas regarding the orientation of the development of hybrid material-based gas sensor in the future are discussed.

19.
Ann Rheum Dis ; 78(3): 380-390, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30254034

RESUMO

OBJECTIVES: The generation of systemic lupus erythematosus (SLE)-related autoantibodies have been shown to be T cell dependent and antigen driven with HLA-DR restriction. In this study, the initiating antigen(s) and the mechanism of autoantibody diversification were investigated. METHODS: T cell epitopes (T-epitopes) of SmD1 (SmD) were mapped by T-T hybridomas generated from DR3+AE0 mice immunised with SmD and with SmD overlapping peptides. TCRs from the reactive hybridomas were sequenced. The core epitopes were determined. Bacterial mimics were identified by bioinformatics. Sera from DR3+AE0 mice immunised with SmD peptides and their mimics were analysed for their reactivity by ELISA and immunohistochemistry. Samples of blood donors were analysed for HLA-DR and autoantibody specificities. RESULTS: Multiple HLA-DR3 restricted T-epitopes within SmD were identified. Many T-T hybridomas reacted with more than one epitope. Some of them were cross-reactive with other snRNP peptides and with proteins in the Ro60/La/Ro52 complex. The reactive hybridomas used unique TCRs. Multiple T-epitope mimics were identified in commensal and environmental bacteria. Certain bacterial mimics shared both T and B cell epitopes with the related SmD peptide. Bacterial mimics induced autoantibodies to lupus-related antigens and to different tissues. HLA-DR3+ blood donors made significantly more SLE-related autoantibodies. CONCLUSIONS: The unique antigenic structures of the lupus-related autoantigens provide the basis for being targeted and for T and B cell epitope spreading and autoantibody diversification with unique patterns. SLE-related autoantibodies are likely generated from responses to commensal and/or environmental microbes due to incomplete negative selection for autoreactive T cells. The production of SLE-related antibodies is inevitable in normal individuals. The findings in this investigation have significant implications in autoimmunity in general.


Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Epitopos de Linfócito T/imunologia , Antígenos HLA-DR/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Animais , Autoimunidade/imunologia , Reações Cruzadas/imunologia , Modelos Animais de Doenças , Camundongos , Proteínas Centrais de snRNP/imunologia
20.
Chem Commun (Camb) ; 54(47): 6056-6059, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29808226

RESUMO

TiO2/TiN core/shell NBs are successfully synthesized, and used as highly efficient photocatalytic H2 evolution catalysts (120 µmol h-1 g-1) from methanol solution. The TiN shell plays dual roles by extending the light absorption range and also promoting the separation/transfer of photoexcited charge carriers as an electron collector.

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