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A novel method for synthesizing substituted 4-chloroquinolines has been devised, utilizing a cascade reaction of N-aryl enaminones promoted by bis(trichloromethyl) carbonate (BTC) and triphenylphosphine oxide (TPPO). This approach features accessible starting materials, a broad substrate range, extensive functional group compatibility, gentle reaction conditions, and straightforward operation. Its versatility is evidenced by its facile scalability and suitability for late-stage derivatization. A plausible mechanism involving α-carbonylation, 6π-azaelectrocyclization, and dehydroxychlorination sequence is proposed.
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Perfluorooctanesulfonate (PFOS), an emerging organic contaminant, necessitates robust on-site detection strategies to safeguard human health and ecological balance. This study introduces a novel point-of-care testing (POCT) platform, combining a hydrogel kit with nanozymes and smartphone technology, for the highly sensitive detection of PFOS. The strategy utilizes copper-substituted cobalt-based Prussian blue analogue nanoboxes (CuCo-PBA NBs), which exhibit intricate hollow structures and remarkable peroxidase-like catalytic activity, efficiently catalyzing the oxidation of chromogenic substrates with hydrogen peroxide (H2O2). Density functional theory calculations elucidate the adsorption dynamics of H2O2 on CuCo-PBA NBs, identifying the factors that improve the catalytic efficiency. The colorimetric POCT platform, integrating the hydrogel kit with a smartphone interface, demonstrates practical utility and achieves a detection limit of 1.43 × 10-8 mol L-1 for PFOS. This research not only presents a new nanozyme design for PFOS detection in diverse matrices, such as lake water, whole blood, urine, and milk, but also paves the way for developing a portable and efficient POCT platform for a variety of emerging contaminants.
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Ácidos Alcanossulfônicos , Fluorocarbonos , Hidrogéis , Peróxido de Hidrogênio , Humanos , Oxirredutases , Peroxidase/química , Peroxidases , Cobalto/química , ColorimetriaRESUMO
A multifunctional single-atom nanozyme, denoted as 3D Ni,N-codoped porous carbon (Ni-NPC), was devised that exhibits remarkable adsorption capabilities and a repertoire of enzyme mimetic functions (oxidase- and peroxidase-like). These attributes stem from the distinctive mesoporous thin-shell structure and well-dispersed Ni sites. The efficient adsorption capacity of Ni-NPC was assessed with respect to three carbamate pesticides (CMPs): metolcarb, carbaryl, and isoprocarb. Moreover, a colorimetric detection method for CMP was established based on its robust peroxidase-like catalytic activity and sequential catalytic interactions with acetylcholinesterase. Furthermore, a portable colorimetric sensor based on a hydrogel sphere integrated with a smartphone platform was devised. This sensor enables rapid, on-site, and quantitative assessment of CMP, boasting an extraordinarily low detection limit of 1.5 ng mL-1. Notably, this sensor was successfully applied to the analysis of CMP levels in lake water and vegetable samples (pakchoi and rape), propelling the progress of real-time detection technologies in food and environment monitoring.
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Praguicidas , Smartphone , Acetilcolinesterase , Praguicidas/análise , Carbamatos/química , Peroxidase , Peroxidases , ColorimetriaRESUMO
Urea assisted overall water splitting represents a cost-effective and efficient technology for hydrogen production, which not only obviates the generation of explosive H2 and O2 gas mixture but also minimizes the energy cost for the water splitting. In this study, we employed a one-pot hydrothermal method to directly synthesize Ni(OH)2 -Ni3 S2 /NF hybrid nanoflowers on a nickel foam (NF) substrate, resulting in efficient and stable bi-functional electrocatalysts for urea oxidation reaction (UOR) and hydrogen evolution reaction (HER). Under alkaline conditions, the Ni(OH)2 -Ni3 S2 /NF catalyst exhibits low voltage requirements of 1.346â V and -0.014â V vs. RHE with a current density of 10â mA cm-2 for UOR and HER, respectively. Furthermore, when employing the Ni(OH)2 -Ni3 S2 /NF catalyst as both anode and cathode for urea-assisted overall water splitting, it requires a cell voltage of merely 1.396â V with a current density of 10â mA cm-2 , which is notably lower than the voltage required for complete water decomposition at the same current density (1.568â V vs. RHE). The one-step synthesis of the Ni(OH)2 -Ni3 S2 /NF catalyst lays a foundation for further exploration of other transition metal complexes as dual-function electrocatalysts, enabling energy-efficient electrolytic hydrogen production and the treatment of urea-rich wastewater.
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Spinal cord injuries (SCIs) often result in limited prospects for recovery and a high incidence of disability. Melatonin (Mel), a hormone, is acknowledged for its neuroprotective attributes. Mel was examined in this study to discover if it alleviates SCIs via the sirtuin1/dynamin-related protein1 (SIRT1/Drp1) signaling pathway. SCIs were simulated in mice by inducing cord contusion at the T9-T10 vertebrae and causing inflammation in primary spinal neurons using lipopolysaccharide (LPS). The findings of our study demonstrated that Mel treatment effectively promoted neuromotor recovery through multiple mechanisms, including the reduction of neuronal death, suppression of astrocyte and microglia activation, and attenuation of neuroinflammation. Moreover, Mel therapy significantly upregulated the expression of SIRT1 in both spinal cord tissues and spinal neurons of mice. Additionally, Mel exhibited the potential to mitigate neuronal mitochondrial dysfunction by modulating the levels of Drp1 and TOMM20, thereby addressing the underlying factors contributing to this dysfunction. Furthermore, when SIRT1 was downregulated, it reversed the positive effects of Mel. Overall, our present study suggests that Mel has the capacity to modulate the SIRT1/Drp1 pathway, thereby ameliorating mitochondrial dysfunction, attenuating inflammation and apoptosis, and enhancing neural function subsequent to SCIs.
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Melatonina , Traumatismos da Medula Espinal , Ratos , Camundongos , Animais , Melatonina/farmacologia , Ratos Sprague-Dawley , Sirtuína 1/metabolismo , Transdução de Sinais , Medula Espinal/metabolismo , Neurônios/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Apoptose/fisiologia , Inflamação , Dinaminas/metabolismoRESUMO
A one-pot cascade chlorination/heterocyclization strategy has been developed for the synthesis of 2,4-dichloro-substituted quinolines from acylated anilines using triphosgene and triphenylphosphine oxide. Obviating the conventional harsh conditions of chlorination, synthetic useful quinolines with moderate to good yields were obtained through this reaction. The mechanism study exhibited that the formation of a ß-enamine intermediate plays a vital role in the generation of the final product.
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Electrocatalytic synthesis under mild conditions has become increasingly important as one of the practical alternatives for industrial applications, especially for the green ammonia (NH3) industry. A properly engineered electrocatalyst plays a vital role in the realization of superior catalytic performance. Among various types of promising nanomaterials, metal-organic frameworks (MOFs) are competitive candidates for developing efficient electrocatalytic NH3 synthesis from simple nitrogen-containing molecules or ions, such as N2 and NO3-. In this review, recent advances in the development of electrocatalysts derived from MOFs for the electrosynthesis of NH3 are collected, categorized, and discussed, including their application in the N2 reduction reaction (NRR) and the NO3- reduction reaction (NO3RR). Firstly, the fundamental principles are illustrated, such as plausible mechanisms of NH3 generation from N2 and NO3-, the apparatus of corresponding electrocatalysis, parameters for evaluation of reaction efficiency, and detection methods of yielding NH3. Then, the electrocatalysts for NRR processes are discussed in detail, including pristine MOFs, MOF-hybrids, MOF-derived N-doped porous carbons, single atomic catalysts from pyrolysis of MOFs, and other MOF-related materials. Subsequently, MOF-related NO3RR processes are also listed and discussed. Finally, the existing challenges and prospects for the rational design and fabrication of electrocatalysts from MOFs for electrochemical NH3 synthesis are presented, such as the evolution of investigation methods with artificial intelligence, innovation in synthetic methods of MOF-related catalysts, advancement of characterization techniques, and extended electrocatalytic reactions.
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The formation of aromatic thioethers from C-S coupling is of great importance in synthetic chemistry. Traditional solution strategies through transition-metal catalysis generally require bulk solution, heat, and longer reaction time. Herein, a mechano-promoted sulfenylation of aryl iodides with nickel catalysis is described. The active aromatic sulfide agents are in-situ generated from aromatic thiol or disulfide and subsequently adapted in the nickel catalytic cycle, with a tolerance of broad substituted groups under optimized conditions. In addition to the gram-scale synthesis that reveals the application potential of the method, the radical trapping and competitive experiments are also conducted for the mechanistic study, thus providing a plausible mechanism rationally. Furthermore, the proposed methodology is certificated as being versatile and following the green principles with ideal calculated values of green chemistry metrics, and the comparison with other approaches for C-S bond formation is also demonstrated.
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In recent years, efficient oil-water separation has gradually become an indispensable part of environmental treatment. Superhydrophobic/superoleophilic materials with excellent self-cleaning performance are urgently required and remain challenging in the investigation of practical, rapid, and efficient separation of oil-water mixture and emulsion, especially those with robust surfaces that can be used in harsh conditions. In this work, a novel superhydrophobic/superoleophilic material was first fabricated by in situ constructing PDMS@ZIF-7/Cu3(PO4)2 hierarchical architectures on a copper mesh, which was adopted as a high flux and efficient separation material for gravity-driven separation of oil-water mixture as well as emulsion. The introduction of crucial Cu3(PO4)2 nanosheet interlayers created the ideal hierarchical structures and serve as partial templates for the subsequent in situ growth of hydrophobic ZIF-7 nanosheets. An improved superhydrophobicity (CA = 155°), permeation flux (102,000 L m-2 h-1), and preferred self-cleaning property were thus achieved by such manipulation of the copper mesh. The PDMS@ZIF-7/Cu3(PO4)2 mesh exhibited exceptional separation efficiency for diverse oil-water mixtures and emulsions attributed to the superhydrophobicity and the demulsification ability and considerable stability to cope with extreme environments including sunlight resistance, low temperature, and corrosion resistance, which prompted its promising applicability in cleaning emulsified wastewater.
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Low-profile angle-stable spacer Zero-P is claimed to reduce the morbidity associated with traditional plate and cage construct (PCC). Both Zero-P and PCC could achieve comparable mid- and long-term clinical and radiological outcomes in anterior cervical discectomy and fusion (ACDF). It is not clear whether Zero-P can reduce the incidence of adjacent segment degeneration (ASD), especially in multi-segmental fusion. This study aimed to test the effect of fusion level with Zero-P versus with PCC on adjacent-segment biomechanics in ACDF. A three-dimensional finite element (FE) model of an intact C2-T1 segment was built and validated. Six single- or double-level instrumented conditions were modeled from this intact FE model using Zero-P or the standard PCC. The biomechanical responses of adjacent segments at the cephalad and caudal levels of the operation level were assessed in terms of range of motion (ROM), stresses in the endplate and disc, loads in the facets. When comparing the increase of adjacent-segment motion in single-level PCC fusion versus Zero-P fusion, a significantly larger increase was found in double-level fusion condition. The fold changes of PCC versus Zero-P of intradiscal and endplate stress, and facet load at adjacent levels in the double-level fusion spine were significantly larger than that in the single-level fusion spine during the sagittal, the transverse, and the frontal plane motion. The increased value of biomechanical features was greater at above segment than that at below. The fold changes of PCC versus Zero-P at adjacent segment were most notable in flexion and extension movement. Low-profile device could decrease adjacent segment biomechanical burden compared to traditional PCC in ACDF, especially in double-level surgery. Zero-P could be a good alternative for traditional PCC in ACDF. Further clinical/in vivo studies will be necessary to explore the approaches selected for this study is warranted.
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Vértebras Cervicais , Fusão Vertebral , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Vértebras Cervicais/fisiologia , Fenômenos Biomecânicos/fisiologia , Placas Ósseas , Discotomia/métodos , Fusão Vertebral/métodos , Amplitude de Movimento Articular/fisiologiaRESUMO
The present study aimed to investigate the association between the serum SIRT1 protein and the severity of spinal cord injury (SCI) as well as the neurological recovery in mice. In this study, the wild-type (WT), Mx1-Cre+ SIRT1loxP/loxP (Mx1), and LCK-Cre+SIRT1loxP/loxP (LCK) mice were subjected to sham surgery, mild, moderate, or severe SCI, respectively. The serum was collected at intervals of 12 h, 1 day (d), 3 d, 5 d, 7 d, 10 d, 14 d, and 21 d after the injury. The locomotor function of all the animals was assessed using the Basso mouse scale (BMS) and the serum SIRT1 proteins were analyzed using enzyme-linked immunosorbent assay (ELISA). The results demonstrated that about 7-10 d after SCI, the levels of SIRT1 protein in the serum correlated significantly with the severity of the injury and at 28 d post-injury, there was a distant neurological recovery (BMS score). The serum SIRT1 concentration in both the Mx1 and LCK mice in the sham group was significantly reduced compared to that in the WT mice, and there was a delayed increase in the serum SIRT1 levels after injury. These findings indicate that the SIRT1 concentrations in the serum of the SCI mice closely correlated with the acute severity and neurological outcome.
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Sirtuína 1 , Traumatismos da Medula Espinal , Animais , Camundongos , Recuperação de Função Fisiológica , Medula EspinalRESUMO
Electrocatalytic nitrogen reduction reaction is a carbon-free and energy-saving strategy for efficient synthesis of ammonia under ambient conditions. Here, we report the synthesis of nanosized Bi2O3 particles grown on functionalized exfoliated graphene (Bi2O3/FEG) via a facile electrochemical deposition method. The obtained free-standing Bi2O3/FEG achieves a high Faradaic efficiency of 11.2% and a large NH3 yield of 4.21 ± 0.14 [Formula: see text] h-1 cm-2 at - 0.5 V versus reversible hydrogen electrode in 0.1 M Na2SO4, better than that in the strong acidic and basic media. Benefiting from its strong interaction of Bi 6p band with the N 2p orbitals, binder-free characteristic, and facile electron transfer, Bi2O3/FEG achieves superior catalytic performance and excellent long-term stability as compared with most of the previous reported catalysts. This study is significant to design low-cost, high-efficient Bi-based electrocatalysts for electrochemical ammonia synthesis.
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Capture and conversion of CO2 into value-added chemicals and fuels is one of the most sought-after hot points at the scientific frontier. Driven by renewable energy derived electricity, the heterogeneous electrocatalyic CO2 reduction has attracted intensive interests because of the easy manipulation and high-energy-density fuels supply. Metals with general abundance and robust ability for activating CO2 have been adopted as the core-atom for developing advanced CO2 reduction electrocatalysts. As the dramatic development of nano-technology, the nanostructured metal-based materials become promising candidates for various catalytic systems. In this Review article, a general introduction and principles applied in CO2 electroreduction are summarized and discussed. Then the proposed reaction pathways of the CO2 reduction were classified and elaborated depending on the products. The state of the art advances related to the nanostructured metallic electrocatalysts are addressed as well. At last, the remaining challenges and further prospects for the construction of new nanostructured electrocatalysts for CO2 reduction and improvement of existing ones have been presented.
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Using structure based drug design, a novel class of potent coagulation factor IXa (FIXa) inhibitors was designed and synthesized. High selectivity over FXa inhibition was achieved. Selected compounds were evaluated in rat IV/PO pharmacokinetic (PK) studies and demonstrated desirable oral PK profiles. Finally, the pharmacodynamics (PD) of this class of molecules were evaluated in thrombin generation assay (TGA) in Corn Trypsin Inhibitor (CTI) citrated human plasma and demonstrated characteristics of a FIXa inhibitor.
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Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Fator IXa/antagonistas & inibidores , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/farmacologia , Administração Oral , Animais , Cristalografia por Raios X , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Compostos Heterocíclicos com 3 Anéis/síntese química , Humanos , Estrutura Molecular , RatosRESUMO
Rhodium-catalyzed C-H allylation of acrylamides with allyl acetates is reported. The use of weakly coordinating directing group resulted in high reaction efficiency, broad functionality tolerance and excellent γ-selectivity, which opens a new synthetic pathway for the access of 1,4-diene skeletons.
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Acetatos/química , Acrilamidas/química , Alcenos/química , Compostos Alílicos/química , Ródio/química , Catálise , ElétronsRESUMO
The Rh(III)-catalyzed C-H alkynylation of acrylamide derivative is realized using a hypervalent alkynyl iodine reagent. The use of a weakly coordinating directing group proved to be of critical importance. This reaction displays broad functional group tolerance and high efficiency, which opens a new synthetic pathway to access functionalized 1,3-enyne skeletons.
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Mipu1 (myocardial ischemic preconditioning upregulated protein 1) is a novel N-terminal Kruppel-associated box (KRAB)/C2H2 zinc finger superfamily protein, that displays a powerful effect in protecting H9c2 cells from oxidative stress-induced cell apoptosis. The present study aims to investigate the effect of Mipu1 overexpression on oxidized low-density lipoprotein (oxLDL)-induced foam cell formation, cell apoptosis, and its possible mechanisms. New Zealand healthy rabbits were used to establish atherosclerosis model, and serum levels of triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol were detected by an automatic biochemical analyzer. Sudan IV staining was used to detect atherosclerotic lesions. The RAW264.7 macrophage cell line was selected as the experimental material. Oil red O staining, high-performance liquid chromatography, and Dil-labeled lipoprotein were used to detect cholesterol accumulation qualitatively and quantitatively, respectively. Flow cytometry was used to determine cell apoptosis. Real-time quantitative polymerase chain reaction (PCR) was used to detect the mRNA expression of the main proteins that are associated with the transport of cholesterol, such as ABCA1, ABCG1, SR-BI, and CD36. Western blot analysis was used to detect the protein expression of Mipu1. There were atherosclerotic lesions in the high-fat diet group with Sudan IV staining. High-fat diet decreased Mipu1 expression and increased CD36 expression significantly at the 10th week compared with standard-diet rabbits. Mipu1 overexpression decreased oxLDL-induced cholesterol accumulation, oxLDL uptake, cell apoptosis, and cleaved caspase-3. Mipu1 overexpression inhibited the oxLDL-induced CD36 mRNA and protein expression, but it did not significantly inhibit the mRNA expression of ABCA1, ABCG1, and SR-BI. Mipu1 overexpression inhibits oxLDL-induced foam cell formation and cell apoptosis. Mipu1 overexpression reduces the lipid intake of macrophages and might be associated with the downregulation of CD36 expression in the presence of oxLDL.
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Apoptose , Células Espumosas/fisiologia , Fatores de Transcrição Kruppel-Like/genética , Lipoproteínas LDL/fisiologia , Animais , Antígenos CD36/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Feminino , Expressão Gênica , Fatores de Transcrição Kruppel-Like/metabolismo , Metabolismo dos Lipídeos , Masculino , Camundongos , CoelhosRESUMO
Rh(III)-catalyzed C-H olefinic alkynylation of enamides for the stereospecific construction of synthetically useful Z-type enynamides is reported. This protocol displays good functionality tolerance and operational simplicity thus providing an alternative synthetic opportunity for the ease of access to specific 1,3-enyne derivatives.
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BACKGROUND: Multicellular organisms consist of cells of many different types that are established during development. Each type of cell is characterized by the unique combination of expressed gene products as a result of spatiotemporal gene regulation. Currently, a fundamental challenge in regulatory biology is to elucidate the gene expression controls that generate the complex body plans during development. Recent advances in high-throughput biotechnologies have generated spatiotemporal expression patterns for thousands of genes in the model organism fruit fly Drosophila melanogaster. Existing qualitative methods enhanced by a quantitative analysis based on computational tools we present in this paper would provide promising ways for addressing key scientific questions. RESULTS: We develop a set of computational methods and open source tools for identifying co-expressed embryonic domains and the associated genes simultaneously. To map the expression patterns of many genes into the same coordinate space and account for the embryonic shape variations, we develop a mesh generation method to deform a meshed generic ellipse to each individual embryo. We then develop a co-clustering formulation to cluster the genes and the mesh elements, thereby identifying co-expressed embryonic domains and the associated genes simultaneously. Experimental results indicate that the gene and mesh co-clusters can be correlated to key developmental events during the stages of embryogenesis we study. The open source software tool has been made available at http://compbio.cs.odu.edu/fly/. CONCLUSIONS: Our mesh generation and machine learning methods and tools improve upon the flexibility, ease-of-use and accuracy of existing methods.
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Inteligência Artificial , Biologia Computacional/métodos , Regulação da Expressão Gênica no Desenvolvimento , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/normas , Máquina de Vetores de Suporte , Animais , Inteligência Artificial/normas , Análise por Conglomerados , Biologia Computacional/normas , Drosophila/embriologia , Drosophila/genética , Perfilação da Expressão Gênica/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , SoftwareRESUMO
Rh(III)-catalyzed direct olefination of arenes with allyl acetate via C-H bond activation is described using N,N-disubstituted aminocarbonyl as the directing group. The catalyst undergoes a redox neutral process, and high to excellent yields of trans-products are obtained. This protocol exhibits a wide spectrum of functionality compatibility because of the simple reaction conditions employed and provides a highly effective synthetic method in the realm of C-H olefination.