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1.
Analyst ; 149(10): 2905-2914, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38572989

RESUMEN

High cost, inherent destabilization, and intricate fixing of enzyme molecules are the main drawbacks of enzyme-based creatinine sensors. The design of a low-cost, stabilizable, and enzyme-free creatinine sensing probe is essential to address these limitations. In this work, an integrated three-dimensional (3D) free-standing electrode was designed to serve as a non-enzymatic creatinine sensing platform and was fabricated by rapid electrodeposition of a dense copper nanoparticle film on nickel foam (Cu NP film/NF). This low-cost, stable, easy-to-fabricate, and binder-free Cu NP film/NF electrode has abundant active sites and excellent electrochemical performance. Cyclic voltammetry measurements show a wide linear range (0.25-24 mM), low detection limit (0.17 mM), and high sensitivity (306 µA mM-1 cm-2). The developed sensor shows high recovery of creatinine concentration in real urine. Besides, it has better specificity, reproducibility, and robustness in detecting creatinine. These excellent results suggest that a non-enzymatic creatinine sensor based on an integrated 3D free-standing Cu NP film/NF electrode has good potential for non-invasive detection of urinary creatinine.


Asunto(s)
Cobre , Creatinina , Electrodos , Galvanoplastia , Límite de Detección , Nanopartículas del Metal , Níquel , Cobre/química , Níquel/química , Creatinina/orina , Creatinina/química , Nanopartículas del Metal/química , Humanos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Reproducibilidad de los Resultados
2.
Appl Microbiol Biotechnol ; 107(24): 7451-7462, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37851105

RESUMEN

Benzoic acid decarboxylases offer an elegant alternative to CO2 fixation by reverse reaction-carboxylation, which is named the bio-Kolbe-Schmitt reaction, but they are unfavorable to carboxylation. Enhancing the carboxylation efficiency of reversible benzoic acid decarboxylases is restricted by the unexplained carboxylation mechanisms. The direction of reversible enzyme catalytic reactions depends on whether catalytic residues at the active center of the enzyme are protonated, which is subjected by the pH. Therefore, the forward and reverse reactions could be separated at different pH values. Reversible 2,3-dihydroxybenzoate acid decarboxylase undergoes decarboxylation at pH 5.0 and carboxylation at pH 8.6. However, it is unknown whether the interaction of enzymes with substrates and products in the forward and reverse reactions can be exploited to improve the catalytic activity of reversible enzymes in the unfavorable direction. Here, we identify a V-shaped tunnel of 2,3-dihydroxybenzoic acid decarboxylase from Aspergillus oryzae (2,3-DHBD_Ao) through which the substrate travels in the enzyme, and demonstrate that the side chain conformation of a tyrosine residue controls the entry and exit of substrate/product during reversible reactions. Together with the kinetic studies of the mutants, it is clarified that interactions between substrate/product traveling through the enzyme tunnel in 2,3-DHBD_Ao are direction-dependent. These results enrich the understanding of the interactions of substrates/products with macromolecular reversible enzymes in different reaction directions, thereby demonstrating a possible path for engineering decarboxylases with higher carboxylation efficiency. KEY POINTS: • The residue Trp23 of 2,3-DHBD_Ao served as a switch to control the entry and exit of catechol • A V-shaped tunnel of 2,3-DHBD_Ao for decarboxylation and carboxylation reactions was identified • The results provide a promising strategy for engineering decarboxylases with direction-dependent residues inside the substrate/product traveling tunnel of the enzyme.


Asunto(s)
Carboxiliasas , Cinética , Carboxiliasas/metabolismo , Catálisis , Ácido Benzoico , Especificidad por Sustrato
3.
Clin Exp Pharmacol Physiol ; 50(11): 855-866, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37582493

RESUMEN

One of the toxic side effects of methotrexate (MTX) is enteritis. Aucubin, an iridoid glycoside derived from traditional medicinal herbs, has been proven to have anti-inflammation, anti-apoptosis and anti-oxidation properties. This work explored the effect and mechanism of aucubin in treating MTX-induced enteritis in a rat model. Two doses of aucubin (5 and 10 mg/kg) were adopted for the assessment of its pharmacological activity. We observed that in rats with MTX-induced enteritis, the body weight and small intestinal weight decreased. The intestine barrier was injured, as reflected by pathological examinations and an increase in D-lactate and diamine oxidase concentration in serum. Intestinal inflammation was shown by the observation of macrophages in the intestine and the concentrations of inflammatory cytokines tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in serum. The NLR family pyrin domain containing 3 (NLRP3) inflammasome was shown to be activated by the enhancement of NLRP3, cleaved-caspase 1, IL-18 and IL-1ß. Moreover, autophagy was reflected by transmission electron microscopy as slightly induced, along with changes in autophagy-related markers microtubule-associated protein 1 light chain 3 (LC3) and Beclin1. Remarkably, aucubin treatment attenuated the MTX-induced disease activity index increase, intestinal damage, inflammatory response and NLRP3 inflammasome activation, but provoked autophagy. Rapamycin, an autophagy activator, showed similar therapeutic effects to aucubin on MTX-induced enteritis. However, 3-methyladenine, an autophagy inhibitor, reversed the protective effects of aucubin. These findings prompted the hypothesis that aucubin alleviates MTX-induced enteritis by aggravating autophagy. This study might provide evidence for further investigation on the therapeutic role of aucubin in MTX-resulted enteritis.


Asunto(s)
Enteritis , Inflamasomas , Ratas , Animales , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Metotrexato/toxicidad , Autofagia , Enteritis/inducido químicamente , Enteritis/tratamiento farmacológico
4.
Crit Rev Eukaryot Gene Expr ; 32(1): 59-65, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35377981

RESUMEN

Previous studies have revealed the role of lncRNA FAM230B in promoting papillary thyroid cancer and gastric cancer. We predicted that FAM230B may interact with miR-203 and studied the crosstalk between FAM230B and miR-203 in osteosarcoma (OS). Paired OS and nontumor tissues donated by 60 patients with OS were subjected to RNA isolations and quantitative real-time PCR (RT-qPCR) to analyze the expression of both FAM230B and miR-203 (mature and premature levels). Subcellular location of FAM230B in OS cells was detected using subcellular fractionation assay. RNA pull-down assay was performed to investigate the direct interaction between FAM230B and miR-203. Overexpression assays followed by RT-qPCR were performed to analyze the role of FAM230B in miR-203 maturation. Cell proliferation was studied with 5-Bromo-2-deoxyUridine (BrdU) assay. FAM230B and premature miR-203 were upregulated in OS, whereas mature miR-203 was downregulated in OS cells. FAM230B was detected in the cytoplasm and directly interacted with premature miR-203. FAM230B overexpression in OS cells increased premature miR-203 level and decreased mature miR-203 level. FAM230B increased cell proliferation and suppressed the role of miR-203 in inhibiting cell proliferation. FAM230B in the cytoplasm may sponge premature miR-203, thereby inhibiting miR-203 maturation to increase OS cell proliferation.


Asunto(s)
Neoplasias Óseas , MicroARNs , Osteosarcoma , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Osteosarcoma/genética , Osteosarcoma/metabolismo , Osteosarcoma/patología
5.
J Integr Plant Biol ; 64(6): 1145-1156, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35419850

RESUMEN

Current gene delivery methods for maize are limited to specific genotypes and depend on time-consuming and labor-intensive tissue culture techniques. Here, we report a new method to transfect maize that is culture-free and genotype independent. To enhance efficiency of DNA entry and maintain high pollen viability of 32%-55%, transfection was performed at cool temperature using pollen pretreated to open the germination aperture (40%-55%). Magnetic nanoparticles (MNPs) coated with DNA encoding either red fluorescent protein (RFP), ß-glucuronidase gene (GUS), enhanced green fluorescent protein (EGFP) or bialaphos resistance (bar) was delivered into pollen grains, and female florets of maize inbred lines were pollinated. Red fluorescence was detected in 22% transfected pollen grains, and GUS stained 55% embryos at 18 d after pollination. Green fluorescence was detected in both silk filaments and immature kernels. The T1 generation of six inbred lines showed considerable EGFP or GUS transcripts (29%-74%) quantitated by polymerase chain reaction, and 5%-16% of the T1 seedlings showed immunologically active EGFP or GUS protein. Moreover, 1.41% of the bar transfected T1 plants were glufosinate resistant, and heritable bar gene was integrated into the maize genome effectively as verified by DNA hybridization. These results demonstrate that exogenous DNA could be delivered efficiently into elite maize inbred lines recalcitrant to tissue culture-mediated transformation and expressed normally through our genotype-independent pollen transfection system.


Asunto(s)
Nanopartículas de Magnetita , Zea mays , ADN , Genotipo , Plantas Modificadas Genéticamente/genética , Polen/genética , Zea mays/genética
6.
J Environ Sci (China) ; 112: 82-93, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34955225

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous priority pollutants that cause great damage to the natural environment and health. Average genome size in a community is critical for shedding light on microbiome's functional response to pollution stress within an environment. Here, microcosms under different concentrations were performed to evaluate the selection of PAHs stress on the average genome size in a community. We found the distinct communities of significantly larger genome size with the increase of PAHs concentration gradients in soils, and consistent trends were discovered in soils at different latitudes. The abundance of Proteobacteria and Deinococcus-Thermus with relatively larger genomes increased along with PAHs stress and well adapted to polluted environments. In contrast, the abundance of Patescibacteria with a highly streamlined and smaller genome decreased, implying complex interactions between environmental selection and functional fitness resulted in bacteria with larger genomes becoming more abundant. Moreover, we confirmed the increased capacity for horizontal transfer of degrading genes between communities by showing an increased connection number per node positively related to the nidA gene along the concentration gradients in the co-occurrence network. Our findings suggest PAHs tend to select bacterial taxa with larger genome sizes, with significant consequences for community stability and potential biodegradation strategies.


Asunto(s)
Bacterias , Tamaño del Genoma , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Bacterias/clasificación , Bacterias/metabolismo , Biodegradación Ambiental , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo
7.
Inflamm Res ; 70(3): 285-296, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33507312

RESUMEN

OBJECTIVE: microRNAs (miRNAs) play critical roles in embryogenesis, cell differentiation and the pathogenesis of several human diseases, including systemic lupus erythematosus (SLE). Toll-like receptors (TLRs) are also known to exert crucial functions in the immune response activation occurring in the pathogenesis of autoimmune diseases like SLE. Herein, the current study aimed to explore the potential role of miR-152-3p in TLR-mediated inflammatory response in SLE. METHODS: We determined the miR-152-3p expression profiles in CD4+ T cells and peripheral blood mononuclear cells (PBMCs) harvested from patients with SLE and healthy controls, and analyzed the correlation between miR-152-3p expression and clinicopathological parameters. CD70 and CD40L expression patterns in CD4+ T cells were assessed by RT-qPCR and flow cytometry. ChIP was adopted to determine the enrichment of DNA methyltransferase 1 (DNMT1) in the promoter region of myeloid differentiation factor 88 (MyD88). RESULTS: The obtained findings revealed that miR-152-3p was highly-expressed in CD4+ T cells and PBMCs of patients with SLE, and this high expression was associated with facial erythema, joint pain, double-stranded DNA, and IgG antibody. DNMT1 could be enriched in the MyD88 promoter, and miR-152-3p inhibited the methylation of MyD88 by targeting DNMT1. We also found that silencing miR-152-3p inhibited MyD88 expression not only to repress the autoreactivity of CD4+ T cells and but also to restrain their cellular inflammation, which were also validated in vivo. CONCLUSION: Our study suggests that miR-152-3p promotes TLR-mediated inflammatory response in CD4+ T cells by regulating the DNMT1/MyD88 signaling pathway, which highlights novel anti-inflammatory target for SLE treatment.


Asunto(s)
Lupus Eritematoso Sistémico/genética , MicroARNs , Adolescente , Adulto , Anciano , Animales , Anticuerpos Antiidiotipos/sangre , Anticuerpos Antinucleares/sangre , Artralgia/genética , Artralgia/inmunología , Niño , Citocinas/inmunología , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/inmunología , Desmetilación , Eritema/genética , Eritema/inmunología , Cara , Femenino , Humanos , Inflamación/genética , Inflamación/inmunología , Leucocitos Mononucleares/inmunología , Lupus Eritematoso Sistémico/inmunología , Masculino , Ratones Endogámicos MRL lpr , Persona de Mediana Edad , Factor 88 de Diferenciación Mieloide/inmunología , Receptores Toll-Like/inmunología , Adulto Joven
8.
Clin Lab ; 67(11)2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34758231

RESUMEN

BACKGROUND: Immunoglobulin D multiple myeloma (IgD-MM) is a rare but aggressive disease. The safety and effectiveness of anti-CD38 monoclonal antibody (daratumumab) have not been known in either IgD-MM or MM complicated with secondary neoplasm. METHODS: A fragile IgD-MM patient had an aggressively relapsed disease concurrent with lung cancer and severe thrombocytopenia, which led to a dilemma for management. After a failure of ixazomib-based chemotherapy, a salvage therapy with daratumumab unexpectedly induced complete remission and platelet recovery, and the patient successfully proceeded to lung cancer surgery. CONCLUSIONS: Our case indicates daratumumab is both safe and effective for refractory IgD-MM with severe complications.


Asunto(s)
Neoplasias Pulmonares , Mieloma Múltiple , Trombocitopenia , Anticuerpos Monoclonales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Humanos , Inmunoglobulina D , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/tratamiento farmacológico , Mieloma Múltiple/complicaciones , Mieloma Múltiple/tratamiento farmacológico , Trombocitopenia/inducido químicamente , Trombocitopenia/tratamiento farmacológico
9.
Genomics ; 112(6): 5157-5169, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32961281

RESUMEN

Root system architecture (RSA), the spatio-temporal configuration of roots, plays vital roles in maize (Zea mays L.) development and productivity. We sequenced the maize root transcriptome of four key growth and development stages: the 6th leaf stage, the 12th leaf stage, the tasseling stage and the milk-ripe stage. Differentially expressed genes (DEGs) were detected. 81 DEGs involved in plant hormone signal transduction pathway and 26 transcription factor (TF) genes were screened. These DEGs and TFs were predicted to be potential candidate genes during maize root growth and development. Several of these genes are homologous to well-known genes regulating root architecture or development in Arabidopsis or rice, such as, Zm00001d005892 (AtERF109), Zm00001d027925 (AtERF73/HRE1), Zm00001d047017 (AtMYC2, OsMYC2), Zm00001d039245 (AtWRKY6). Identification of these key genes will provide a further understanding of the molecular mechanisms responsible for maize root growth and development, it will be beneficial to increase maize production and improve stress resistance by altering RSA traits in modern breeding.


Asunto(s)
Genes de Plantas , Raíces de Plantas/genética , Zea mays/genética , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Fenotipo , Reguladores del Crecimiento de las Plantas/fisiología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Reacción en Cadena de la Polimerasa , RNA-Seq , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo
10.
Pituitary ; 23(3): 253-257, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32157493

RESUMEN

PURPOSE: Multi-syphilitic gummas in pituitary and cerebellopontine angle (CPA) are extremely rare and easily misdiagnosed especially in patients with antibiotic abuse. We write this paper for clinicians to better understanding of cerebral gumma. METHODS: We report a patient with syphilitic gummas in pituitary and left CPA. The definite diagnosis is made by histopathology after surgery. RESULTS: A 49-years-old woman suffered from headaches with tinnitus and hypoacusis in left ear. She was diagnosed with syphilis but untreated. There were no chancre and rashes in the course of disease. Syphilis serological tests were positive. Brain MRI found two masses located in the left CPA and hypophysial fossa. The two masses were removed successively. We found a large number of Treponemapallidum in paraffin-embedded specimens by immunohistochemical staining. CONCLUSIONS: Syphilitic gummas in pituitary and CPA are similar to benign or malignant brain tumors, easily leading to misdiagnosis. Gumma should be considered in differential diagnosis when a patient has unexplained nervous system symptoms or signs and imaging findings suggest intracranial mass in syphilis seropositive patients.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Ángulo Pontocerebeloso/diagnóstico por imagen , Ángulo Pontocerebeloso/patología , Neurosífilis/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Ángulo Pontocerebeloso/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Neurosífilis/patología , Neurosífilis/cirugía
11.
Genomics ; 111(6): 1395-1403, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-30268779

RESUMEN

Bashang long-tail chickens are an indigenous breed with dual purpose in China (meat and eggs) but have low egg laying performance. To improve the low egg laying performance, a genome-wide analysis of mRNAs and long noncoding RNAs (lncRNAs) from Bashang long-tail chickens and Hy-Line brown layers was performed. A total of 16,354 mRNAs and 8691 lncRNAs were obtained from ovarian follicles. Between the breeds, 160 mRNAs and 550 lncRNAs were found to be significantly differentially expressed. Integrated network analysis suggested some differentially expressed genes were involved in ovarian follicular development through oocyte meiosis, progesterone-mediated oocyte maturation, and cell cycle. The impact of lncRNAs on cis and trans target genes, indicating some lncRNAs may play important roles in ovarian follicular development. The current results provided a catalog of chicken ovarian follicular lncRNAs and genes for further study to understand their roles in regulation of egg laying performance.


Asunto(s)
Pollos/genética , Redes Reguladoras de Genes , Genoma , Folículo Ovárico/metabolismo , ARN Largo no Codificante/genética , ARN Mensajero/genética , Animales , Pollos/clasificación , China , Femenino , Perfilación de la Expresión Génica , Folículo Ovárico/citología
12.
Chem Soc Rev ; 47(9): 3189-3216, 2018 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-29512678

RESUMEN

Graphene has attracted considerable attention due to its unique two-dimensional structure, high electronic mobility, exceptional thermal conductivity, excellent optical transmittance, good mechanical strength, and ultrahigh surface area. To meet the ever increasing demand for portable electronic products, electric vehicles, smart grids, and renewable energy integrations, hybridizing graphene with various functions and components has been demonstrated to be a versatile and powerful strategy to significantly enhance the performance of various energy storage systems such as lithium-ion batteries, supercapacitors and beyond, because such hybridization can result in synergistic effects that combine the best merits of involved components and confer new functions and properties, thereby improving the charge/discharge efficiencies and capabilities, energy/power densities, and cycle life of these energy storage systems. This review will focus on diverse graphene hybridization principles and strategies for energy storage applications, and the proposed outline is as follows. First, graphene and its fundamental properties, followed by graphene hybrids and related hybridization motivation, are introduced. Second, the developed hybridization formulas of using graphene for lithium-ion batteries are systematically categorized from the viewpoint of material structure design, bulk electrode construction, and material/electrode collaborative engineering; the latest representative progress on anodes and cathodes of lithium-ion batteries will be reviewed following such classifications. Third, similar hybridization formulas for graphene-based supercapacitor electrodes will be summarized and discussed as well. Fourth, the recently emerging hybridization formulas for other graphene-based energy storage devices will be briefed in combination with typical examples. Finally, future prospects and directions on the exploration of graphene hybridization toward the design and construction of viable, high-class, and even newly-featured (e.g., flexible) energy storage materials, electrodes, and systems will be presented.

13.
Small ; 14(24): e1800752, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29745010

RESUMEN

Building stable and efficient electron and ion transport pathways are critically important for energy storage electrode materials and systems. Herein, a scallop-inspired shell engineering strategy is proposed and demonstrated to confine high volume change silicon microparticles toward the construction of stable and high volumetric capacity binder-free lithium battery anodes. As for each silicon microparticle, the methodology involves an inner sealed but adaptable overlapped graphene shell, and an outer open hollow shell consisting of interconnected reduced graphene oxide, mimicking the scallop structure. The inner closed shell enables simultaneous stabilization of the interfaces of silicon with both carbon and electrolyte, substantially facilitates efficient and rapid transport of both electrons and lithium ions from/to silicon, the outer open hollow shell creates stable and robust transport paths of both electrons and lithium ions throughout the electrode without any sophisticated additives. The resultant self-supported electrode has achieved stable cycling with rapidly increased coulombic efficiency in the early stage, superior rate capability, and remarkably high volumetric capacity upon a facile pressing process. The rational design and engineering of graphene shells of the silicon microparticles developed can provide guidance for the development of a wide range of other high capacity but large volume change electrochemically active materials.

14.
Microb Pathog ; 123: 246-249, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30030140

RESUMEN

Bacillus halotolerans is a rhizobacterium with the potential to promote plant growth and tolerance to drought and salinity stress. Here, we present the complete genome sequence of B. halotolerans ZB201702, which consists of 4,150,000 bp in a linear chromosome, including 3074 protein-coding sequences, 30 rRNAs, and 85 tRNAs. Genome analysis revealed many putative gene clusters involved in defense mechanisms. Activity analysis of the strain under salt and simulated drought stress suggests tolerance to abiotic stresses. The complete genome information of B. halotolerans ZB201702 could provide valuable insights into rhizobacteria-mediated plant salt and drought tolerance and rhizobacteria-based solutions for abiotic stress agriculture.


Asunto(s)
Bacillus/genética , Bacillus/aislamiento & purificación , Sequías , Rizosfera , Microbiología del Suelo , Estrés Fisiológico , Secuenciación Completa del Genoma , Bacillus/clasificación , Bacillus/fisiología , Proteínas Bacterianas/genética , Genes Bacterianos/genética , Genes de ARNr/genética , Salinidad , Tolerancia a la Sal , Cloruro de Sodio/metabolismo , Suelo , Especificidad de la Especie
15.
Beilstein J Org Chem ; 14: 672-681, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29623130

RESUMEN

The design of orange-light emitting, thermally activated, delayed fluorescence (TADF) materials is necessary and important for the development and application of organic light-emitting diodes (OLEDs). Herein, two donor-acceptor-donor (D-A-D)-type orange TADF materials based on fluorenone and acridine, namely 2,7-bis(9,9-dimethylacridin-10(9H)-yl)-9H-fluoren-9-one (27DACRFT, 1) and 3,6-bis(9,9-dimethylacridin-10(9H)-yl)-9H-fluoren-9-one (36DACRFT, 2), were successfully synthetized and characterized. The studies on their structure-property relationship show that the different configurations have a serious effect on the photoluminescence and electroluminescence performance according to the change in singlet-triplet splitting energy (ΔEST) and excited state geometry. This indicates that a better configuration design can reduce internal conversion and improve triplet exciton utilization of TADF materials. Importantly, OLEDs based on 2 exhibited a maximum external quantum efficiency of 8.9%, which is higher than the theoretical efficiency of the OLEDs based on conventional fluorescent materials.

16.
Biochem Biophys Res Commun ; 478(2): 752-8, 2016 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-27498027

RESUMEN

NUCLEAR FACTOR-Y (NF-Y) has been shown to play an important role in growth, development, and response to environmental stress. A NF-Y complex, which consists of three subunits, NF-YA, NF-YB, and, NF-YC, binds to CCAAT sequences in a promoter to control the expression of target genes. Although NF-Y proteins have been reported in Arabidopsis and rice, a comprehensive and systematic analysis of ZmNF-Y genes has not yet been performed. To examine the functions of ZmNF-Y genes in this family, we isolated and characterized 50 ZmNF-Y (14 ZmNF-YA, 18 ZmNF-YB, and 18 ZmNF-YC) genes in an analysis of the maize genome. The 50 ZmNF-Y genes were distributed on all 10 maize chromosomes, and 12 paralogs were identified. Multiple alignments showed that maize ZmNF-Y family proteins had conserved regions and relatively variable N-terminal or C-terminal domains. The comparative syntenic map illustrated 40 paralogous NF-Y gene pairs among the 10 maize chromosomes. Microarray data showed that the ZmNF-Y genes had tissue-specific expression patterns in various maize developmental stages and in response to biotic and abiotic stresses. The results suggested that ZmNF-YB2, 4, 8, 10, 13, and 16 and ZmNF-YC6, 8, and 15 were induced, while ZmNF-YA1, 3, 4, 6, 7, 10, 12, and 13, ZmNF-YB15, and ZmNF-YC3 and 9 were suppressed by drought stress. ZmNF-YA3, ZmNF-YA8 and ZmNF-YA12 were upregulated after infection by the three pathogens, while ZmNF-YA1 and ZmNF-YB2 were suppressed. These results indicate that the ZmNF-Ys may have significant roles in the response to abiotic and biotic stresses.


Asunto(s)
Factor de Unión a CCAAT/genética , Cromosomas de las Plantas/química , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Proteínas de Plantas/genética , Zea mays/genética , Secuencia de Aminoácidos , Arabidopsis/clasificación , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/microbiología , Basidiomycota/patogenicidad , Basidiomycota/fisiología , Factor de Unión a CCAAT/clasificación , Secuencia Conservada , Sequías , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Análisis por Micromatrices , Familia de Multigenes , Oryza/clasificación , Oryza/genética , Oryza/crecimiento & desarrollo , Oryza/microbiología , Filogenia , Proteínas de Plantas/clasificación , Alineación de Secuencia , Estrés Fisiológico , Sintenía , Zea mays/clasificación , Zea mays/crecimiento & desarrollo , Zea mays/microbiología
17.
Nanotechnology ; 27(12): 124001, 2016 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-26891478

RESUMEN

Two blue fluorescent emitters were utilized to construct simplified organic light-emitting diodes (OLEDs) and the remarkable difference in device performance was carefully illustrated. A maximum current efficiency of 4.84 cd A(-1) (corresponding to a quantum efficiency of 4.29%) with a Commission Internationale de l'Eclairage (CIE) coordinate of (0.144, 0.127) was achieved by using N,N-diphenyl-4″-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1, 1':4', 1″-terphenyl]-4-amine (BBPI) as a non-doped emission layer of the simplified blue OLEDs without carrier-transport layers. In addition, simplified fluorescent/phosphorescent (F/P) hybrid warm white OLEDs without carrier-transport layers were fabricated by utilizing BBPI as (1) the blue emitter and (2) the host of a complementary yellow phosphorescent emitter (PO-01). A maximum current efficiency of 36.8 cd A(-1) and a maximum power efficiency of 38.6 lm W(-1) were achieved as a result of efficient energy transfer from the host to the guest and good triplet exciton confinement on the phosphorescent molecules. The blue and white OLEDs are among the most efficient simplified fluorescent blue and F/P hybrid white devices, and their performance is even comparable to that of most previously reported complicated multi-layer devices with carrier-transport layers.

19.
Nano Lett ; 15(9): 6222-8, 2015 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-26308100

RESUMEN

We propose a novel material/electrode design formula and develop an engineered self-supporting electrode configuration, namely, silicon nanoparticle impregnated assemblies of templated carbon-bridged oriented graphene. We have demonstrated their use as binder-free lithium-ion battery anodes with exceptional lithium storage performances, simultaneously attaining high gravimetric capacity (1390 mAh g(-1) at 2 A g(-1) with respect to the total electrode weight), high volumetric capacity (1807 mAh cm(-3) that is more than three times that of graphite anodes), remarkable rate capability (900 mAh g(-1) at 8 A g(-1)), excellent cyclic stability (0.025% decay per cycle over 200 cycles), and competing areal capacity (as high as 4 and 6 mAh cm(-2) at 15 and 3 mA cm(-2), respectively). Such combined level of performance is attributed to the templated carbon bridged oriented graphene assemblies involved. This engineered graphene bulk assemblies not only create a robust bicontinuous network for rapid transport of both electrons and lithium ions throughout the electrode even at high material mass loading but also allow achieving a substantially high material tap density (1.3 g cm(-3)). Coupled with a simple and flexible fabrication protocol as well as practically scalable raw materials (e.g., silicon nanoparticles and graphene oxide), the material/electrode design developed would propagate new and viable battery material/electrode design principles and opportunities for energy storage systems with high-energy and high-power characteristics.

20.
Vet Dermatol ; 27(3): 135-e36, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27072328

RESUMEN

BACKGROUND: The melanocortin 1 receptor (MC1R) gene plays an important role in the control of coat colour in mammals. Genetic variation of the MC1R gene and the relationship between genotype and coat colour are not well understood. Studies in the fox may improve our understanding of gene influence on coat colour in dogs and cats. HYPOTHESIS/OBJECTIVES: To investigate coat colour associated mutations in the coding region of MC1R gene in foxes. ANIMALS: A total of 118 foxes, comprising 70 red foxes (Vulpes vulpes) (19 red, 10 white silver, 29 silver and 12 chocolate foxes) and 48 arctic foxes (Vulpes lagopus) (9 dominant white blue foxes and 39 normal blue foxes) were included in the study. METHODS: Evaluation of the DNA sequence of the coding region of MC1R gene and its polymorphisms. RESULTS: Eight polymorphic sites (single nucleotide polymorphisms, SNPs) distributed throughout the 954-bp coding region of the fox MC1R gene were detected. Among them, c.13G>T, c.124A>G, c.289G>A, c.373T>C and c.839 T>G were mis-sense mutations, which resulted in codon change of p.G5C, p.N42D, p.V97I, p.C125R and p.F280C, respectively. Mutation and haplotype analysis indicated that c.373T>C was associated with black and brown pigmented phenotypes in foxes, and c.13G>T and c.839T>G were important in distinguishing V. lagopus and V. vulpes. CONCLUSIONS AND CLINICAL IMPORTANCE: SNP c.373T>C in the coding region of the MC1R gene is probably associated with the brown phenotype of chocolate foxes.


Asunto(s)
Zorros/genética , Pigmentos Biológicos/genética , Polimorfismo de Nucleótido Simple/genética , Receptor de Melanocortina Tipo 1/genética , Animales , Secuencia de Bases , ADN/genética , Cabello
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