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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38701417

RESUMO

Transcription factors (TFs) are proteins essential for regulating genetic transcriptions by binding to transcription factor binding sites (TFBSs) in DNA sequences. Accurate predictions of TFBSs can contribute to the design and construction of metabolic regulatory systems based on TFs. Although various deep-learning algorithms have been developed for predicting TFBSs, the prediction performance needs to be improved. This paper proposes a bidirectional encoder representations from transformers (BERT)-based model, called BERT-TFBS, to predict TFBSs solely based on DNA sequences. The model consists of a pre-trained BERT module (DNABERT-2), a convolutional neural network (CNN) module, a convolutional block attention module (CBAM) and an output module. The BERT-TFBS model utilizes the pre-trained DNABERT-2 module to acquire the complex long-term dependencies in DNA sequences through a transfer learning approach, and applies the CNN module and the CBAM to extract high-order local features. The proposed model is trained and tested based on 165 ENCODE ChIP-seq datasets. We conducted experiments with model variants, cross-cell-line validations and comparisons with other models. The experimental results demonstrate the effectiveness and generalization capability of BERT-TFBS in predicting TFBSs, and they show that the proposed model outperforms other deep-learning models. The source code for BERT-TFBS is available at https://github.com/ZX1998-12/BERT-TFBS.


Assuntos
Redes Neurais de Computação , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Sítios de Ligação , Algoritmos , Biologia Computacional/métodos , Humanos , Aprendizado Profundo , Ligação Proteica
2.
Nano Lett ; 24(12): 3801-3810, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38477714

RESUMO

The effectiveness of various cancer therapies for solid tumors is substantially limited by the highly hypoxic tumor microenvironment (TME). Here, a microalgae-integrated living hydrogel (ACG gel) is developed to concurrently enhance hypoxia-constrained tumor starvation therapy and immunotherapy. The ACG gel is formed in situ following intratumoral injection of a biohybrid fluid composed of alginate, Chlorella sorokiniana, and glucose oxidase, facilitated by the crossing-linking between divalent ions within tumors and alginate. The microalgae Chlorella sorokiniana embedded in ACG gel generate abundant oxygen through photosynthesis, enhancing glucose oxidase-catalyzed glucose consumption and shifting the TME from immunosuppressive to immunopermissive status, thus reducing the tumor cell energy supply and boosting antitumor immunity. In murine 4T1 tumor models, the ACG gel significantly suppresses tumor growth and effectively prevents postoperative tumor recurrence. This study, leveraging microalgae as natural oxygenerators, provides a versatile and universal strategy for the development of oxygen-dependent tumor therapies.


Assuntos
Chlorella , Microalgas , Neoplasias , Animais , Camundongos , Hidrogéis , Glucose Oxidase , Fotossíntese , Hipóxia , Oxigênio , Imunoterapia , Alginatos , Microambiente Tumoral
3.
J Proteome Res ; 23(6): 2054-2066, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38775738

RESUMO

The metabolites and microbiota in tongue coating display distinct characteristics in certain digestive disorders, yet their relationship with colorectal cancer (CRC) remains unexplored. Here, we employed liquid chromatography coupled with tandem mass spectrometry to analyze the lipid composition of tongue coating using a nontargeted approach in 30 individuals with colorectal adenomas (CRA), 32 with CRC, and 30 healthy controls (HC). We identified 21 tongue coating lipids that effectively distinguished CRC from HC (AUC = 0.89), and 9 lipids that differentiated CRC from CRA (AUC = 0.9). Furthermore, we observed significant alterations in the tongue coating lipid composition in the CRC group compared to HC/CRA groups. As the adenoma-cancer sequence progressed, there was an increase in long-chain unsaturated triglycerides (TG) levels and a decrease in phosphatidylethanolamine plasmalogen (PE-P) levels. Furthermore, we noted a positive correlation between N-acyl ornithine (NAOrn), sphingomyelin (SM), and ceramide phosphoethanolamine (PE-Cer), potentially produced by members of the Bacteroidetes phylum. The levels of inflammatory lipid metabolite 12-HETE showed a decreasing trend with colorectal tumor progression, indicating the potential involvement of tongue coating microbiota and tumor immune regulation in early CRC development. Our findings highlight the potential utility of tongue coating lipid analysis as a noninvasive tool for CRC diagnosis.


Assuntos
Neoplasias Colorretais , Lipidômica , Fosfatidiletanolaminas , Espectrometria de Massas em Tandem , Língua , Humanos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/microbiologia , Lipidômica/métodos , Masculino , Feminino , Língua/microbiologia , Língua/metabolismo , Língua/patologia , Língua/química , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem/métodos , Fosfatidiletanolaminas/metabolismo , Fosfatidiletanolaminas/análise , Idoso , Cromatografia Líquida , Lipídeos/análise , Lipídeos/química , Triglicerídeos/metabolismo , Triglicerídeos/análise , Adenoma/metabolismo , Adenoma/microbiologia , Esfingomielinas/análise , Esfingomielinas/metabolismo , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/metabolismo , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/química , Plasmalogênios/análise , Plasmalogênios/metabolismo , Plasmalogênios/química , Estudos de Casos e Controles , Etanolaminas/metabolismo , Etanolaminas/análise , Etanolaminas/química , Ceramidas/metabolismo , Ceramidas/análise , Adulto
4.
Plant Physiol ; 189(2): 889-905, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35188194

RESUMO

Mediating induced abscisic acid (ABA) biosynthesis is important for enhancing plant stress tolerance. Here, we found that rice (Oryza sativa L.) osa-miR2105 (miR2105) and the Stress/ABA-activated protein kinase (OsSAPK10) coordinately regulate the rice basic region-leucine zipper transcription factor (bZIP TF; OsbZIP86) at the posttranscriptional and posttranslational levels to control drought-induced ABA biosynthesis via modulation of rice 9-cis-epoxycarotenoid dioxygenase (OsNCED3) expression. OsbZIP86 expression is regulated by miR2105-directed cleavage of the OsbZIP86 mRNA. OsbZIP86 encodes a nuclear TF that binds to the promoter of the ABA biosynthetic gene OsNCED3. OsSAPK10 can phosphorylate and activate OsbZIP86 to enhance the expression of OsNCED3. Under normal growth conditions, altered expression of miR2105 and OsbZIP86 displayed no substantial effect on rice growth. However, under drought conditions, miR2105 knockdown or OsbZIP86 overexpression transgenic rice plants showed higher ABA content, enhanced tolerance to drought, lower rates of water loss, and more stomatal closure of seedlings, compared with wild-type rice Zhonghua 11; in contrast, miR2105 overexpression, OsbZIP86 downregulation, and OsbZIP86 knockout plants displayed opposite phenotypes. Collectively, our results show that the "miR2105-(OsSAPK10)-OsbZIP86-OsNCED3" module regulates the drought-induced ABA biosynthesis without penalty on rice growth under normal conditions, suggesting candidates for improving drought tolerance in rice.


Assuntos
Oryza , Ácido Abscísico/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética
5.
Opt Express ; 31(16): 26245-26253, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710489

RESUMO

In this work, by comparing and analyzing dynamic biasing InGaAs/InAlAs avalanche photodiodes(APDs) with different active areas, it is found that they have different noise suppression frequency ranges. The upper limit frequency(defined as the frequency at which the noise suppression effect begins to fail) of InGaAs/InAlAs APDs with active area diameter of 50 µm, 100 µm and 200 µm are 2400 MHz, 1990MHz and 1400 MHz respectively. In addition, for InGaAs/InAlAs APDs with an active area diameter of 50 µm, 100 µm and 200 µm, their optimal frequencies of dynamic biasing (defined as the frequency corresponding to the optimal SNR) are 1877MHz, 1670 MHz and 1075 MHz respectively. At last, applying dynamic biasing technology, it achieves a useful gain of 6698.1, which is much greater than that of DC bias (47.2), and this technology has the potential to be applied in high sensitivity laser radar receivers.

6.
Virus Genes ; 59(5): 670-677, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37328638

RESUMO

Epstein-Barr virus (EBV) is the first identified human oncogenic herpesvirus infecting over 90% of the adults worldwide. However, the safe and effective prophylactic vaccine has not been licensed. The major glycoprotein 350 (gp350) on the EBV envelope is the main target for neutralizing antibodies, and gp350 (aa15-320) was used for the development of monoclonal antibodies in present study. The purified recombinant gp35015-320aa with an estimated molecular weight of 50 kDa was used to immunize six-week-old BALB/c mice, and the hybridoma cell lines that stably secreted monoclonal antibodies (mAbs) were obtained. The ability of developed mAbs for capturing and neutralizing EBV was evaluated, and mAb 4E1 presented better performance to block the infection of EBV in cell line Hone-1. The mAb 4E1 recognized the epitope. Its sequence of variable region genes (VH and VL) presented a unique identity which hadn't been reported. The developed mAbs might benefit the antiviral therapy and immunologic diagnosis for EBV infection.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Adulto , Animais , Camundongos , Humanos , Herpesvirus Humano 4/genética , Anticorpos Monoclonais , Anticorpos Antivirais , Anticorpos Neutralizantes , Glicoproteínas/genética
7.
Biotechnol Lett ; 45(11-12): 1431-1440, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37736778

RESUMO

OBJECTIVES: Human heart-type fatty acid binding protein (HFABP) is a biomarker for diagnosis, risk assessment, and prognosis of acute myocardial infarction, and we aimed to establish an immunoassay for HFABP quantitation. METHODS: Human HFABP monoclonal antibodies (mAbs) were developed, evaluated by enzyme-linked immunosorbent assay, and a chemiluminescence enzyme immunoassay (CLEIA) generated. Analytical performance of the CLEIA was evaluated by measuring serum HFABP. RESULTS: The prokaryotically expressed rHFABP was purified and four anti-HFABP mAbs with superior detection performance were obtained after immunizing BALB/c mice. MAbs 2B8 and 6B3 were selected as respective capture and detection antibodies for HFABP measurement by CLEIA (detection range, 0.01-128 µg/L). Results using the CLEIA showed excellent correlation (r, 0.9622) and the correlation coefficient was 0.9809 (P < 0.05) by the Tukey test statistical analysis with those of latex-enhanced immunoturbidimetry in hospitals. CONCLUSION: Our mAbs and CLEIA for HFABP detection represent new diagnostic tools for measurement of human serum HFABP.


Assuntos
Anticorpos Monoclonais , Luminescência , Animais , Camundongos , Humanos , Ensaio de Imunoadsorção Enzimática/métodos , Imunoensaio/métodos , Biomarcadores
8.
BMC Microbiol ; 22(1): 249, 2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253713

RESUMO

BACKGROUND: Tuberculosis (TB) caused by Mycobacterium tuberculosis (M. tb) remains a global health issue. The characterized virulent M. tb H37Rv, avirulent M. tb H37Ra and BCG strains are widely used as reference strains to investigate the mechanism of TB pathogenicity. Here, we attempted to determine metabolomic signatures associated with the Mycobacterial virulence in human macrophages through comparison of metabolite profile in THP-1-derived macrophages following exposure to the M. tb H37Rv, M. tb H37Ra and BCG strains. RESULTS: Our findings revealed remarkably changed metabolites in infected macrophages compared to uninfected macrophages. H37Rv infection specifically induced 247 differentially changed metabolites compared to H37Ra or BCG infection. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed H37Rv specifically induces tryptophan metabolism. Moreover, quantitative PCR (qPCR) results showed that indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan 2,3-dioxygenase 2 (TDO2) which converts the tryptophan to a series of biologically second metabolites were up-regulated in H37Rv-infected macrophages compared to H37Ra- or BCG-infected macrophages, confirming the result of enhanced tryptophan metabolism induced by H37Rv infection. These findings indicated that targeting tryptophan (Trp) metabolism may be a potential therapeutic strategy for pulmonary TB. CONCLUSIONS: We identified a number of differentially changed metabolites that specifically induced in H37Rv infected macrophages. These signatures may be associated with the Mycobacterial virulence in human macrophages. The present findings provide a better understanding of the host response associated with the virulence of the Mtb strain.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Vacina BCG , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Macrófagos/microbiologia , Metabolômica , Triptofano/metabolismo , Triptofano Oxigenase/metabolismo , Tuberculose/microbiologia
9.
Genet Res (Camb) ; 2022: 3895396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35645615

RESUMO

Purpose: Pancreatic cancer (PC) is a common, highly lethal cancer with a low survival rate. Autophagy is involved in the occurrence and progression of PC. This study aims to explore the feasibility of using an autophagy-related long noncoding RNA (lncRNA) signature for assessing PC patient survival. Methods: We obtained RNA sequencing and clinical data of patients from the TCGA website. Autophagy genes were obtained from the Human Autophagy Database. The prognostic model, generated through univariate and multivariate Cox regression analyses, included 10 autophagy-related lncRNAs. Receiver operating characteristic (ROC) curves and forest plots were generated for univariate and multivariate Cox regression analyses, to examine the predictive feasibility of the risk model. Gene set enrichment analysis (GSEA) was used to screen enriched gene sets. Results: Twenty-eight autophagy-related lncRNAs were filtered out through univariate Cox regression analysis (P < 0.001). Ten autophagy-related lncRNAs, including 4 poor prognosis factors and 6 beneficial prognosis factors, were further screened via multivariate Cox regression analysis. The AUC value of the ROC curve was 0.815. GSEA results demonstrated that cancer-related gene sets were significantly enriched. Conclusion: A signature based on ten autophagy-related lncRNAs was identified. This signature could be potentially used for evaluating clinical prognosis and might be used for targeted therapy against PC.


Assuntos
Neoplasias Pancreáticas , RNA Longo não Codificante , Autofagia/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pancreáticas/genética , Prognóstico , RNA Longo não Codificante/genética , Neoplasias Pancreáticas
10.
Fish Shellfish Immunol ; 124: 261-272, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35427776

RESUMO

Mitogen-activated protein kinase kinase 6 (MKK6) and activator protein-1 (AP-1) are two of the essential regulatory proteins in the p38 mitogen-activated protein kinase (MAPK) pathway, which participates in the innate immune response to bacterial infections. In this study, molluscan MKK6 (AwMKK6) and AP-1 (AwAP-1) genes were cloned and identified from Anodonta woodiana. The open reading frame (ORF) of AwMKK6 encodes for a putative polypeptide sequence of 345 amino acids containing a conserved serine/threonine protein kinase (S_TKc) domain, a SVAKT motif and a DVD domain. AwAP-1 consists of 294 amino acids including a typical nuclear localization signal (NLS), a Jun domain and a basic region leucine zipper (BRLZ) domain. Quantitative real-time PCR analysis showed that both AwMKK6 and AwAP-1 were widely expressed in all selected tissues of A. woodiana and their transcript levels in hemocytes were significantly upregulated when challenged with Aeromonas hydrophila and lipopolysaccharide (LPS). Additionally, the signaling molecules of the AwMKK6/AwAP-1 pathway including AwTLR4, AwMyD88, AwTRAF6, AwMEKK1, AwMEKK4, AwASK1, AwTAK1 and Awp38 mRNA expression showed a stronger responsiveness to LPS challenge in hemocytes of A. woodiana. RNA interference (RNAi) experiments indicated that the silencing of AwMKK6 or AwAP-1 could decrease the mRNA expression levels of immune effectors (AwTNF, AwLYZ and AwDefense). Subcellular localization studies suggested that AwMKK6 and AwAP-1 were distributed throughout the cells and nucleus, respectively, and their overexpression could significantly enhance the transcriptional activities of AP-1-Luc in HEK293T cells. These findings suggest that MKK6 and AP-1 play a major role in the host defense response to bacterial injection, which may make contributions to a better understanding of the immune function of the p38 MAPK pathway in mollusks.


Assuntos
Anodonta , Aminoácidos , Animais , Anodonta/genética , Células HEK293 , Humanos , Imunidade Inata/genética , Lipopolissacarídeos/farmacologia , RNA Mensageiro/metabolismo , Fator de Transcrição AP-1/genética
11.
Fish Shellfish Immunol ; 120: 82-91, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34780976

RESUMO

Mitogen-activated protein kinase kinase kinase 4 (MAP3K4) is a multifunctional mediator of the conserved MAPK signaling pathway that plays essential roles in the regulation of immune responses in mammals. However, the function of teleost MAP3K4s in innate immunity, especially in the intestinal immune system, is still poorly understood. In the current study, we identified a fish MAP3K4 homolog (CiMAP3K4) in Ctenopharyngodon idella as well as its immune function in intestine following bacterial infection in vivo and in vitro. The open reading frame (ORF) of CiMAP3K4 encodes putative peptide of 1544 amino acids containing a predicted serine/threonine protein kinase (S_TKc) domain with high identity with other fish MAP3K4s. Phylogenetic analysis revealed the CiMAP3K4 belonged to the fish cluster and showed the closest relationship to Pimephales promelas. Quantitative real-time PCR (qRT-PCR) analysis revealed that CiMAP3K4 transcripts were widely distributed in all tested tissues, especially with high expression in the muscle and intestine of healthy grass carp. In vitro, CiMAP3K4 gene expression was upregulated by bacterial PAMPs (lipolysaccharide (LPS), peptidoglycan (PGN), L-Ala-γ-D-Glu-meso-diaminopimelic acid (Tri-DAP) and muramyl dipeptide (MDP)) and pathogens (Aeromonas hydrophila and Aeromonas veronii) in primary intestinal cells. In vivo, the mRNA expression levels of CiMAP3K4 in the intestine were significantly induced by bacterial MDP challenge in a time-dependent manner; however, this effect could be inhibited by the bioactive dipeptides ß-alanyl-l-histidine (carnosine) and alanyl-glutamine (Ala-Gln). Moreover, CiMAP3K4 was located primarily in the cytoplasm, and its overexpression increased the transcriptional activity of AP-1 in HEK293T cells. Collectively, these results suggested that CiMAP3K4 might play an important role in the intestinal immune response to bacterial infections, which paves the way for a better understanding of the intestinal immune system of grass carp.


Assuntos
Carpas , Doenças dos Peixes , Proteínas de Peixes , Infecções por Bactérias Gram-Negativas , MAP Quinase Quinase Quinase 4 , Aeromonas hydrophila , Animais , Carpas/genética , Carpas/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes/genética , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Células HEK293 , Humanos , Imunidade Inata/genética , Intestinos/imunologia , Intestinos/microbiologia , MAP Quinase Quinase Quinase 4/genética , Filogenia
12.
Chem Soc Rev ; 50(2): 945-985, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33226037

RESUMO

Cell primitive-based functional materials that combine the advantages of natural substances and nanotechnology have emerged as attractive therapeutic agents for cancer therapy. Cell primitives are characterized by distinctive biological functions, such as long-term circulation, tumor specific targeting, immune modulation etc. Moreover, synthetic nanomaterials featuring unique physical/chemical properties have been widely used as effective drug delivery vehicles or anticancer agents to treat cancer. The combination of these two kinds of materials will catalyze the generation of innovative biomaterials with multiple functions, high biocompatibility and negligible immunogenicity for precise cancer therapy. In this review, we summarize the most recent advances in the development of cell primitive-based functional materials for cancer therapy. Different cell primitives, including bacteria, phages, cells, cell membranes, and other bioactive substances are introduced with their unique bioactive functions, and strategies in combining with synthetic materials, especially nanoparticulate systems, for the construction of function-enhanced biomaterials are also summarized. Furthermore, foreseeable challenges and future perspectives are also included for the future research direction in this field.


Assuntos
Antineoplásicos/farmacologia , Materiais Biomiméticos/farmacologia , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Materiais Biomiméticos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias/patologia
13.
Angew Chem Int Ed Engl ; 61(24): e202202380, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35363418

RESUMO

Herein, we report a general strategy for achieving ultra-pure green emissions by suppressing the shoulder peaks in the emission spectra of conventional polycyclic aromatic hydrocarbons (PAHs). Through precise synthetic fusion of multi-resonance (MR) fragments with conventional PAH, extended π-conjugation lengths, increased molecular rigidity, and reduced vibrational frequency could be simultaneously realized. The proof-of-concept emitters exhibited ultra-pure green emissions with dominant peaks at ca. 521 nm, photoluminescence quantum yields that are greater than 99 %, a small full-width-at-half-maximum of 23 nm, and CIE coordinates of (0.16, 0.77). The bottom-emitting organic light-emitting diode (OLED) exhibited a record-high CIEy value of 0.74 and a high maximum external quantum efficiency of 30.5 %. The top-emitting OLED not only achieved a BT.2020 green color (CIE: 0.17, 0.78) for the first time but also showed superior performance among all green OLED devices, with a current efficiency of 220 cd A- .

14.
Angew Chem Int Ed Engl ; 61(14): e202117181, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35092123

RESUMO

Nitrogen-containing polycyclic heteroaromatics have exhibited fascinating multi-resonance (MR) characteristics for efficient narrowband emission, but strategies to bathochromic shift their emissions while maintaining the narrow bandwidths remain exclusive. Here, homogeneous hexatomic rings are introduced into nitrogen-embedded MR skeletons to prolong the π-conjugation length for low-energy electronic transitions while retaining the non-bonding character of the remaining parts. The proof-of-the-concept emitters exhibit near unity photoluminescence quantum yields with peaks at 598 nm and 620 nm and small full-width-at-half-maximums of 28 nm and 31 nm, respectively. Optimal organic light-emitting diodes exhibit a high external quantum efficiency of 18.2 %, negligible efficiency roll-off, and ultra-long lifetime with negligible degradation at an initial luminance of 10 000 cd m-2 after 94 hours.

15.
Angew Chem Int Ed Engl ; 61(38): e202206916, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35754001

RESUMO

Polycyclo-heteraborin multi-resonance (MR) emitters are promising for high color-purity organic light-emitting diodes (OLEDs). Here, unlike the most common heteroatom ternary-doped (X/B/N) frameworks, a binary-doped (B/N) skeleton is reported with a large energy band for wide-range color tunability. Based on this parent-segment, a "one-pot" catalyst-free borylation method is developed which generates deep blue to pure green MR emitters from readily available starting materials, with peaks at 426-532 nm and full-width-at-half-maxima of 27-38 nm. Impressively, a maximum external quantum efficiency of nearly 40 % is recorded for the corresponding device with Commission Internationale de l'Eclairage coordinates of (0.14, 0.16), representing the state-of-the-art performances. This work presents a new paradigm and synthesis of B/N-doped MR emitters and will motivate the study of other novel frameworks.

16.
Angew Chem Int Ed Engl ; 61(40): e202207293, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35749578

RESUMO

Despite the remarkable multiple resonance (MR) optoelectronic properties of organic nanographenes with boron and nitrogen atoms disposed para to each other, the synthetic procedures are sophisticated with low yields and the molecular skeletons are limited. Here, a new paradigm of easy-to-access MR emitter is constructed by simplifying the multiborylation through amine-directed formation of B-N bonds while introducing an additional para-positioned nitrogen atom to trigger the MR effect. The proof-of-concept molecules exhibit narrowband emissions at 480 and 490 nm, with full width at half maxima (FWHMs) of only 29 and 34 nm. The devices based on them showed external quantum efficiencies (EQE) of >33.0 %, which remained above 24.0 % even at a high brightness of 5000 cd m-2 . This is the first example of MR emitters with a B-N covalent bond, not only decreasing the synthesis difficulty but also increasing the diversity of MR skeletons for emerging new optoelectronic properties.

17.
New Phytol ; 230(4): 1639-1652, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33533489

RESUMO

Phytohormone, particularly jasmonate (JA) and salicylate (SA) signaling, plays a central role in plant responses to herbivore and pathogen attack. Generally, SA mediates resistance responses against biotrophic pathogens and phloem-feeding insects, while JA mediates responses against necrotrophic pathogens and chewing insects. The phytohormonal responses mediating rice resistance to a piercing-sucking herbivore, the brown planthopper (BPH), remains unknown. Here, we combined transcriptome analysis, hormone measurements, genetic analysis and a field study to address this issue. Infestation by BPH adult females resulted in significant transcriptional reprograming. The upregulated genes were enriched in the JA signaling pathway. Consistently, the concentrations of JAs, but not SA, were dramatically increased in response to BPH attack. Two JA-deficient lines (AOC and MYC2 knockout) and two SA-deficient lines (nahG overexpression and NPR1 knockout) were constructed. BPH performed better on JA-deficient lines than on wild-type (WT) plants, but similarly on SA-deficient and WT plants. During BPH attack, the accumulation of defensive secondary metabolites was attenuated in JA-deficient lines compared with WT plants. Moreover, MYC2 mutants were more susceptible to planthoppers than WT plants in nature. This study reveals that JA signaling functions in rice defense against BPH.


Assuntos
Hemípteros , Oryza , Animais , Ciclopentanos , Dissecação , Feminino , Regulação da Expressão Gênica de Plantas , Herbivoria , Oryza/genética , Oxilipinas , Reguladores de Crescimento de Plantas , Plantas Geneticamente Modificadas , Ácido Salicílico , Transdução de Sinais
18.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33921941

RESUMO

How to construct efficient red-emitting thermally activated delayed fluorescence (TADF) materials is a challenging task in the field of organic light-emitting diodes (OLEDs). Herein, an electron acceptor moiety, 3,6-DCNB-DPPZ, with high rigidity and strong acceptor strength was designed by introducing two cyanobenzene groups into the 3,6-positions of a dipyrido[3,2-a:2',3'-c]phenazine unit. A red-emitting compound, 3,6_R, has been designed and synthesized by combining the rigid acceptor unit with two triphenylamine donors. Due to high molecular rigidity and strong intramolecular charge transfer characteristic in donor-acceptor-donor skeleton, 3,6_R exhibited a red emission with a high photoluminescence quantum yield of 86% and distinct TADF nature with short delayed fluorescence lifetime of about 1 microsecond. Accordingly, the OLED using 3,6_R as the guest emitter gained a high external quantum efficiency of 12.0% in the red region with an electroluminescence peak of 619 nm and favorable Commission Internationale de l'Eclairage coordinates of (0.62, 0.38).

19.
AAPS PharmSciTech ; 22(1): 20, 2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33389225

RESUMO

The aim of present study was to evaluate the feasibility of a naringenin-hydroxypropyl-ß-cyclodextrin (naringenin-HPßCD) inhalation solution for pulmonary delivery. Naringenin, a flavanone derived from citrus fruits, has been proven to exhibit excellent peripheral antitussive effect. To address the limitation of its poor oral bioavailability and low local concentration in the lung, a naringenin-HPßCD inhalation solution was prepared for pulmonary delivery. The aerosolization performance of formulation was evaluated by next generation impactor (NGI). Both dose-dependent and time-dependent antitussive effects of naringenin-HPßCD inhalation solution on acute cough induced by citric acid in guinea pigs were investigated. In vitro toxicity of naringenin-HPßCD inhalation solution in pulmonary Calu-3 cells was evaluated by MTS assay, and in vivo local toxicity investigation was achieved by assessing bronchoalveolar lavage (BALF) and lung histology after a 7-day inhalation treatment in guinea pigs. Fine particle fraction (FPF) of the formulation was determined as 53.09%. After inhalation treatment of 15 min, naringenin-HPßCD inhalation solution within the studied range of 0.2-3.6 mg/kg could dose-dependently reduce the cough frequency with the antitussive rate of 29.42-39.42%. Naringenin-HPßCD inhalation solution in concentration range of 100-400 µM did not decrease cell viability of Calu-3 cells, and the maximum effective dose (3.6 mg/kg) was non-toxic during the short-term inhalation treatment for guinea pigs. In conclusion, naringenin-HPßCD inhalation solution was capable for nebulization and could provide rapid response with reduced dose for the treatment of cough.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/administração & dosagem , Aerossóis/química , Antitussígenos/administração & dosagem , Flavanonas/administração & dosagem , 2-Hidroxipropil-beta-Ciclodextrina/química , Administração por Inalação , Animais , Disponibilidade Biológica , Flavanonas/química , Cobaias , Pulmão , beta-Ciclodextrinas/administração & dosagem
20.
Biochem Biophys Res Commun ; 529(1): 91-96, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32560825

RESUMO

As structural components of biological membranes, phytosterols are essential not only for a variety of cellular functions but are also precursors for brassinosteroid (BR) biosynthesis. Plant CYP51 is the oldest and most conserved obtusifoliol 14α-demethylase in eukaryotes and is an essential component of the sterol biosynthesis pathway. However, little is known about rice (Oryza sativa L.) CYP51G1. In this study, we showed that rice OsCYP51G1 shared high homology with obtusifoliol 14α-demethylase and OsCYP51G1 was strongly expressed in most of rice organs. Subcellular localization analysis indicated that OsCYP51G1 was localized to the endoplasmic reticulum. Knockdown and knockout of OsCYP51G1 resulted in delayed flowering, impaired membrane integrity, abnormal pollen, and reduced grain yield, whereas OsCYP51G1 overexpression led to increased grain yield. Knockdown of OsCYP51G1 also reduced the levels of end-products (sitosterol and stigmasterol) and increased those of upstream intermediates (24-methylene-cycloartenol and cycloeucalenol) of the OsCYP51G1-mediated sterol biosynthesis step. In contrast, overexpression of OsCYP51G1 increased the sitosterol and stigmasterol content and reduced that of cycloeucalenol. However, knockdown of OsCYP51G1 by RNAi did not elicit these BR deficiency-related phenotypes, such as dwarfism, erect leaves and small seeds, nor was the leaf lamina angle sensitive to brassinolide treatment. These results revealed that rice OsCYP15G1 encodes an obtusifoliol 14α-demethylase for the phytosterols biosynthesis and possible without affecting the biosynthesis of downstream BRs, which was different from its homolog, OsCYP51G3.


Assuntos
Oryza/metabolismo , Fitosteróis/biossíntese , Proteínas de Plantas/metabolismo , Esterol 14-Desmetilase/metabolismo , Brassinosteroides/biossíntese , Regulação da Expressão Gênica de Plantas , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Genes de Plantas , Germinação/genética , Oryza/genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Interferência de RNA , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Esterol 14-Desmetilase/genética
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