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Solid-state lithium-sulfur batteries have shown prospects as safe, high-energy electrochemical storage technology for powering regional electrified transportation. Owing to limited ion mobility in crystalline polymer electrolytes, the battery is incapable of operating at subzero temperature. Addition of liquid plasticizer into the polymer electrolyte improves the Li-ion conductivity yet sacrifices the mechanical strength and interfacial stability with both electrodes. In this work, we showed that by introducing a spherical hyperbranched solid polymer plasticizer into a Li+ -conductive linear polymer matrix, an integrated dynamic cross-linked polymer network was built to maintain fully amorphous in a wide temperature range down to subzero. A quasi-solid polymer electrolyte with a solid mass content >90 % was prepared from the cross-linked polymer network, and demonstrated fast Li+ conduction at a low temperature, high mechanical strength, and stable interfacial chemistry. As a result, solid-state lithium-sulfur batteries employing the new electrolyte delivered high reversible capacity and long cycle life at 25 °C, 0 °C and -10 °C to serve energy storage at complex environmental conditions.
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To improve the color conversion performance, we study the nanoscale-cavity effects on the emission efficiency of a colloidal quantum dot (QD) and the Förster resonance energy transfer (FRET) from quantum well (QW) into QD in a GaN porous structure (PS). For this study, we insert green-emitting QD (GQD) and red-emitting QD (RQD) into the fabricated PSs in a GaN template and a blue-emitting QW template, and investigate the behaviors of the photoluminescence (PL) decay times and the intensity ratios of blue, green, and red lights. In the PS samples fabricated on the GaN template, we observe the efficiency enhancements of QD emission and the FRET from GQD into RQD, when compared with the samples of surface QDs, which is attributed to the nanoscale-cavity effect. In the PS samples fabricated on the QW template, the FRET from QW into QD is also enhanced. The enhanced FRET and QD emission efficiencies in a PS result in an improved color conversion performance. Because of the anisotropic PS in the sample surface plane, the polarization dependencies of QD emission and FRET are observed.
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In Li-ion batteries, functional cosolvents could significantly improve the specific performance of the electrolyte, for example, the flame retardancy. In case the cosolvent shows strong Li+-coordinating ability, it could adversely influence the electrochemical Li+-intercalation reaction of the electrode. In this work, a noncoordinating functional cosolvent was proposed to enrich the functionality of the electrolyte while avoiding interference with the Li storage process. Hexafluorocyclotriphosphazene, an efficient flame-retardant agent with proper physicochemical properties, was chosen as a cosolvent for preparing functional electrolytes. The nonpolar phosphazene molecules with low electron-donating ability do not coordinate with Li+ and thus are excluded from the primary solvation sheath. In graphite-anode-based Li-ion batteries, the phosphazene molecules do not cointercalate with Li+ into the graphite lattice during the charging process, which helps to maintain integral anode structure and interface and contributes to stable cycling. The noncoordinating cosolvent was also applied to other types of electrode materials and batteries, paving a new way for high-performance electrochemical energy storage systems with customizable functions.
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Although the method of inserting colloidal quantum dots (QDs) into deep nano-holes fabricated on the top surface of a light-emitting diode (LED) has been widely used for producing effective Förster resonance energy transfer (FRET) from the LED quantum wells (QWs) into the QDs to enhance the color conversion efficiency, an important mechanism for enhancing energy transfer in such an LED structure was overlooked. This mechanism, namely, the nanoscale-cavity effect, represents a near-field Purcell effect and plays a crucially important role in enhancing the color conversion efficiency. Here, we demonstrate the results of LED performance, time-resolved photoluminescence (TRPL), and numerical simulation to elucidate the nanoscale-cavity effect on color conversion by inserting a photoresist solution of red-emitting QDs into the nano-holes fabricated on a blue-emitting QW LED. Based on the TRPL study of the inserted QDs in a nano-hole structure fabricated on an un-doped GaN template of no QW, it is found that the emission efficiency of the inserted QDs is significantly increased due to the nanoscale-cavity effect. From the simulation study, it is confirmed that this effect can also increase the FRET efficiency, particularly for those radiating dipoles in the QWs oriented perpendicular to the sidewalls of the nano-holes. In the nanoscale-cavity effect, the enhanced near field distribution inside a nano-hole excited by a light emitter modifies its own radiation behavior through the Purcell effect such that its far-field emission becomes stronger.
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In this paper, we first elaborate on the effects of surface plasmon (SP) coupling on the modulation responses of the emission of a light-emitting diode (LED) and its down-converted lights through colloidal quantum dots (QDs). The results of our past efforts for this subject are briefly discussed. The discussions lay the foundation for the presentation of the new experimental data of such down-converted lights in this paper. In particular, the enhancement of the modulation bandwidth (MB) of a QD-based converted light through SP coupling is demonstrated. By linking green-emitting QDs (GQDs) and/or red-emitting QDs (RQDs) with synthesized Ag nano-plates via surface modifications and placing them on a blue-emitting LED, the MBs of the converted green and red emissions are significantly increased through the induced SP coupling of the Ag nano-plates. When both GQD and RQD exist and are closely spaced in a sample, the energy transfer processes of emission-reabsorption and Förster resonance energy transfer from GQD into RQD occur, leading to the increase (decrease) in the MB of green (red) light. With SP coupling, the MB of a mixed light is significantly enhanced.
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Pontos Quânticos , Transferência Ressonante de Energia de Fluorescência , LuzRESUMO
Bioinspired palladium-catalyzed intramolecular cyclization of amino acid derivatives containing a vinyl iodide moiety by C-H activation enabled rapid access to a wide range of functionalized proline derivatives with an exocyclic olefin. To demonstrate the practicality of this methodology, the functionalized prolines were used as intermediates for the synthesis of several natural products: lucentamycin A, oxotomaymycin, oxoprothracarcin, and barmumycin.
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Produtos Biológicos , Paládio , Catálise , Ciclização , Estrutura Molecular , Paládio/química , ProlinaRESUMO
Long non-coding RNAs (lncRNAs), a class of long RNAs, are longer than 200 nucleotides in length but lack protein-coding capacity. LncRNAs, as critical genomic regulators, are involved in genomic imprinting regulation, histone modification and gene expression regulation as well as tumor initiation and progression. However, it is also found that lncRNAs are associated with drug resistance in several types of cancer. Drug resistance is an important reason for clinical chemotherapy failure, and the molecular mechanism of tumor resistance is complex, which is a process of multi-cause, multi-gene and multi-signal transduction pathway interaction. Then comprehending the mechanisms of chemoresistance will help find ways to control the tumor progression effectively. Therefore, in this review, we will construct lncRNAs /drug resistance interaction network and shed light on the role of lncRNAs in drug resistance.
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Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias/tratamento farmacológico , RNA Longo não Codificante/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , MicroRNAs/genética , Neoplasias/genética , Neoplasias/patologia , Transdução de Sinais/genéticaRESUMO
BACKGROUND AND AIMS: Theory predicts that outcrossing should be more prevalent among perennials than annuals, a pattern confirmed by comparative evidence from diverse angiosperm families. However, intraspecific comparisons between annual and perennial populations are few because such variation is uncommon among flowering plants. Here, we test the hypothesis that perennial populations outcross more than annual populations by investigating Incarvillea sinensis, a wide-ranging insect-pollinated herb native to China. The occurrence of both allopatric and sympatric populations allows us to examine the stability of mating system differences between life histories under varying ecological conditions. METHODS: We estimated outcrossing rates and biparental inbreeding in 16 allopatric and five sympatric populations in which both life histories coexisted using 20 microsatellite loci. In each population we measured height, branch number, corolla size, tube length and herkogamy for ~30 individuals. In a sympatric population, we recorded daily flower number, pollinator visitation and the fruit and seed set of annual and perennial plants. KEY RESULTS: As predicted, outcrossing rates (t) were considerably higher in perennial (meanâ =â 0.76) than annual (meanâ =â 0.09) populations. This difference in mating system was also maintained at sympatric sites where plants grew intermixed. In both allopatric and sympatric populations the degree of herkogamy was consistently larger in outcrossing than selfing plants. Perennials were more branched, with more and larger flowers than in annuals. In a sympatric population, annuals had a significantly higher fruit and seed set than perennials. CONCLUSIONS: Genetically based differences in herkogamy between annuals and perennials appear to play a key role in governing outcrossing rates in populations, regardless of variation in local ecological conditions. The maintenance of mating system and life history trait differentiation between perennial and annual populations of I. sinensis probably results from correlated evolution in response to local environmental conditions.
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Flores , Reprodução , Animais , Flores/genética , Endogamia , Insetos , Polinização , SementesRESUMO
Herein, we have reported a nickel-catalyzed cascade reductive thiolation of aryl halides with sulfinates driven by paired electrolysis. This protocol uses sulfinates as the sulfur source, and various thioethers could be synthesized under mild conditions. By mechanism exploration, we find that a cascade chemical step is allowed on the electrode interface and could alter the reaction pathway in paired electrolysis, whose findings could help the discovery of novel cascade reactions with unique reactivity.
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A concise chemical synthesis of (+)-haperforin G in 20 steps from commercially available starting materials is achieved with the integration of the Co-catalyzed intramolecular Pauson-Khand reaction for the stereoselective construction of cyclopentanone bearing an all-carbon quaternary stereogenic center at the bridge-head position and the light-initiated photocatalysis for convergent and asymmetric cross-coupling of the unstabilized C(sp3)-radical with an enone. The developed chemistry paves the way to synthesizing structurally diverse analogs of haperforin G (6).
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The prevalence of obesity is growing, and high fat diet (HFD)-induced obesity can alter the brain and cognition. However, the link between HFD, hippocampal function, and inflammation is still not fully understood. Tripartite motif (TRIM) family has been implicated in various cellular processes, such as apoptosis, neurogenesis, and innate immune responses. Trim69, a member of TRIM family, was investigated in the present study to determine its role in HFD-induced hippocampal damage. Here, we first found that hippocampal Trim69 expression was markedly down-regulated in wild-type (WT) mice challenged with HFD. Trim69 knockout (KO) mice exhibited an exaggerated version of the metabolic disorder after HFD challenge, as evidenced by their increased body weight and elevated insulin resistance. HFD-induced hippocampal injury was further aggravated by Trim69 deletion, as confirmed by the reduced survival of neurons and increased level of apoptotic cell death. In addition, the inflammatory response triggered by HFD was more pronounced in the hippocampi of Trim69-KO mice after blockage of the activation of the nuclear factor kappa B (NF-κB) signaling pathway. Phosphorylation of mitogen-activated protein kinase (MAPK) kinase 4 (MKK4), MKK7, and c-Jun N-terminal kinase (JNK) in the hippocampi of HFD-challenged mice was intensified by the loss of Trim69. Hippocampal-apoptosis-signal-regulating kinase 1 (ASK1) phosphorylation was also found to be up-regulated by HFD, especially in mice with Trim69 deletion. Of note, we found that Trim69 directly interacted with and deubiquitinated ASK1 in microglial cells. Microglial cell-specific suppression of Trim69 exacerbated inflammation and apoptosis in response to lipopolysaccharide (LPS). Trim69 over-expression markedly alleviated LPS-induced inflammatory response and apoptotic cell death in microglial cells. Together, these results indicated that Trim69 might be a functionally essential inhibitor of ASK1 activation during the pathogenesis of hippocampal inflammation and apoptosis, and it could serve as a novel molecular target for obesity-associated brain damage.
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Apoptose , Hipocampo/metabolismo , Inflamação , MAP Quinase Quinase Quinase 5/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Dieta Hiperlipídica , Hipocampo/patologia , Masculino , Camundongos , Camundongos Knockout , Microglia/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Obesidade/metabolismo , Obesidade/patologia , Transdução de Sinais , Ubiquitina/metabolismoRESUMO
Peptide nucleic acid (PNA) is an oligomer, in which the phosphate backbone has been replaced by a pseudopeptide backbone that is meant to mimic DNA. Peptide nucleic acids are of the utmost importance in the biomedical field because of their ability to hybridize with neutral nucleic acids and their special chemical and biological properties. In recent years, PNAs have emerged in nanobiotechnology for cancer diagnosis and therapy due to their high affinity and sequence selectivity toward corresponding DNA and RNA. In this review, we summarize the recent progresses that have been made in cancer detection and therapy with PNA biotechnology. In addition, we emphasize nanoparticle PNA-based strategies for the efficient delivery of drugs in anticancer therapies.
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Antineoplásicos/uso terapêutico , Biotecnologia , Nanomedicina , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Ácidos Nucleicos Peptídicos/química , Portadores de Fármacos/química , Humanos , Nanopartículas/químicaRESUMO
The interest in discovering and developing natural antimicrobials has significantly increased due to consumer preferences for foods that are free of chemical preservatives while still microbiologically safe. One of the best sources of natural antimicrobials is certain mushrooms (fungi) as many of them not only have nutraceutical functions but also possess antimicrobial properties. This article reviews the available information on mushroom antimicrobials for food safety control. It includes available resources, extraction procedures, antimicrobial activities, and the status of their applications to food safety. The review indicates that there are great potential benefits to be gained from mushroom antimicrobials in food production, processing, and preservation as a biosolution to meet the increasing demands for food quality and safety.
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BCL-2 Associated athanogene 1 (BAG-1) and Xeroderma pigmentosum group D (XPD) are involved in the nucleotide excision repair pathway and DNA repair. We aimed to investigate whether polymorphisms in BAG-1 and XPD have effects on chemotherapy sensitivity and survival in patients with advanced non-small-cell lung cancer (NSCLC) treated with vinorelbine combined cisplatin (NP) regimen. A total of 142 patients with diagnosed advanced NSCLC were recruited in the current study. NP regimen was applied for all eligible patients. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for BAG-1 (codon 324) and XPD (codons 312 and 751) genotyping. The treatment response was evaluated according to the RECIST guidelines. Progression-free survival (PFS) and overall survival (OS) were record as median and end point, respectively. As for BAG-1 codon 324, the chemotherapy sensitivity in NSCLC patients with CT genotype was 0.383 times of those with CC genotype (P < 0.05). With respect to XPD codon 751, the chemotherapy sensitivity in NSCLC patients with Lys/Gln genotype was 0.400 times of those with Lys/Lys genotype (P < 0.05). In addition, NSCLC patients carrying combined C/C genotype at codon 324 in BAG-1, Asp/Asp of XPD codon 312, and Lys/Lys of XPD codon 751 produced a higher efficacy of NP chemotherapy compared to those carrying mutation genotypes (all P < 0.05). Further, there were significant differences in PFS between patients with combined C/C genotype of BAG-1 codon 324, Lys/Lys genotype of XPD codon 751, and Asp/Asp genotype of XPD codon 312 and patients carrying BAG-1 codon 324 C/T genotype, XPD codon751 Lys/Gln genotype, and XPD codon312 Asp/Asn genotype (P < 0.05). Multivariate Cox regression analysis indicated that the combined wild-type of codon 324 XPD, codon 751 XPD, and codon 312 BAG-1 is the protective factor for OS and PFS, and clinical stages is the risk factor for OS and PFS. In conclusion, our research demonstrated the combined effects of BAG-1 and XPD polymorphisms on chemotherapy sensitivity and survival in patients with advanced NSCLC, which might be the important predictive markers for platinum-based chemotherapy efficacy.
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Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ligação a DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fatores de Transcrição/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , VinorelbinaRESUMO
The Paeonia ostii, also known as "Feng Dan" have a crucial role in folk medicine to treat lumbar muscles strain, knee osteoarthritis and cervical spondylosis. In this study, four new phenolic compounds, specifically Paeoniaostiph A-E (1-4) phenolic compounds were characterised through spectroscopic techniques, including 1D and 2D NMR, HRESIMS, UV, IR, and electronic circular dichroism computations to explore their structures. Cytotoxicity and NO production inhibition of the new phenolic compounds were also studied. The results of the cytotoxicity experiment showed that compound 1 is cytotoxic to two human cancer cell lines with IC50 values ranging from 13.3 to 13.5 µM. Compounds 1 and 2 showed certain inhibitory activity on NO production. This is the first report on isolating the components from natural sources.
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A protocol for the electrooxidative [3+2] annulation to generate indolo[2,3-b]indoles in an undivided cell is reported. It exhibits good yields with excellent regioselectivities and tolerates various functional groups without external chemical oxidants. Cyclic voltammetry and density functional theory calculations indicate that the [3+2] annulation is initiated by the simultaneous anodic oxidation of indole and aniline derivatives, and the step to determine the rate relies on the combination of radical cations.
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BACKGROUND: The expression patterns and prognostic value of Procollagen-lysine, 2-oxoglutarate 5-dioxygenase (PLOD) family genes in breast cancer remain to be elucidated. METHODS: The expression levels, prognostic value, and biological function of PLODs were determined using Oncomine, cBioPortal, GEPIA, Timer, UALCAN, PrognoScan, GeneMANIA, Metascape, and breast cancer tissue microarrays. RESULTS: The expressions of PLOD1 and PLOD3 were upregulated in breast cancer tissues, indicating worse clinical stages. High expression levels of PLOD family genes were associated with worse disease-free survival and distant metastasis-free survival, while high expression levels of PLOD1 and PLOD3 were related to worse overall survival in all breast cancer patients. The levels of PLOD family genes were all significantly higher in the age ≤51 y group, HR-negative patients, and triple negative breast cancer (TNBC) patients. They are associated with tumor-infiltrating immune cells (TIICs), including CD4+ T cells, CD8+ T cells, B cells, macrophages, neutrophils, and dendritic cells. According to co-expression gene analysis and functional enrichment, they are associated with protein hydroxylation, collagen biosynthesis and modifying enzymes, collagen metabolism, RNA splicing, extracellular matrix organization, VEGFA-VEGFR2 signaling pathway, and skeletal system development. Immunohistochemistry showed that the expressions of all PLOD family genes were significantly elevated in breast cancer tissues. PLOD1 expression was positively correlated with ER, TNBC status, and tumor grade. PLOD2 expression was positively connected with Ki-67 status. PLOD3 expression was positively related with age and tumor grade. CONCLUSIONS: PLOD family genes are novel potential prognostic biomarkers for breast cancer, and targeting PLOD inhibitors might be an effective strategy for breast cancer therapy.
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Neoplasias da Mama , Regulação Neoplásica da Expressão Gênica , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase , Humanos , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismo , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Prognóstico , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismoRESUMO
Aliphatic allylic amines are common in natural products and pharmaceuticals. The oxidative intermolecular amination of C(sp3)-H bonds represents one of the most straightforward strategies to construct these motifs. However, the utilization of widely internal alkenes with amines in this transformation remains a synthetic challenge due to the inefficient coordination of metals to internal alkenes and excessive coordination with aliphatic and aromatic amines, resulting in decreasing the reactivity of the catalyst. Here, we present a regioselective Cu-catalyzed oxidative allylic C(sp3)-H amination of internal olefins with azodiformates to these problems. A removable bidentate directing group is used to control the regiochemistry and stabilize the π-allyl-metal intermediate. Noteworthy is the dual role of azodiformates as both a nitrogen source and an electrophilic oxidant for the allylic C-H activation. This protocol features simple conditions, remarkable scope and functional group tolerance as evidenced by >40 examples and exhibits high regioselectivity and excellent E/Z selectivity.
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The high-capacity advantage of lithium metal anode was compromised by common use of copper as the collector. Furthermore, lithium pulverization associated with "dead" Li accumulation and electrode cracking deteriorates the long-term cyclability of lithium metal batteries, especially under realistic test conditions. Here, we report an ultralight, integrated anode of polyimide-Ag/Li with dual anti-pulverization functionality. The silver layer was initially chemically bonded to the polyimide surface and then spontaneously diffused in Li solid solution and self-evolved into a fully lithiophilic Li-Ag phase, mitigating dendrites growth or dead Li. Further, the strong van der Waals interaction between the bottommost Li-Ag and polyimide affords electrode structural integrity and electrical continuity, thus circumventing electrode pulverization. Compared to the cutting-edge anode-free cells, the batteries pairing LiNi0.8Mn0.1Co0.1O2 with polyimide-Ag/Li afford a nearly 10% increase in specific energy, with safer characteristics and better cycling stability under realistic conditions of 1× excess Li and high areal-loading cathode (4 milliampere hour per square centimeter).
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Immune checkpoint inhibitors (ICIs) have been shown to be significant in improving the overall survival rate in certain malignancies with poor prognoses. However, only 20-40% of patients achieve long-term benefits, highlighting the relevance of the factors that influence the treatment, which can help clinicians improve their results and guide the development of new immune checkpoint therapies. In this study, the current pharmacokinetic aspects associated with the ICIs and the factors influencing clinical efficacy were characterised, including in terms of drug metabolism, drug clearance, hormonal effects and immunosuppressive effects.