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The uranium recovery from high concentration fluorine-containing uranium wastewater is a desired research target in the field of environmental radiochemistry but is very challenging due to the formation of stable uranium fluoride complexes that are quite difficult to extract. By employing surface defect engineering and interfacial heterostructure design, we present here the rational design of an efficient photocatalyst (Ag/WO3-x) for U(VI) uptake from fluorine-containing uranium wastewater without any sacrificial agents. The defect-rich surface of Ag/WO3-x facilitates confined adsorption of uranium, while the introduction of Ag nanoparticles enables both efficient electron-hole separation and a plasmon effect upon light irradiation. Ag/WO3-x shows high U(VI) removal efficiency of 96.3% at 8 mg/L U(VI) within 60 min. Notably, even when the ratio of F- to U(VI) is as high as 20:1, the removal efficiency of U(VI) by Ag/WO3-x reaches up to 95%. Additionally, the maximum capture capacity of U(VI) on Ag/WO3-x reaches 676.8 mg/g at 200 mg/L of U(VI) within 60 min, which is superior to ever-reported photocatalysts in fluorine-containing uranium wastewater. This work provides an effective way for the uranium capture from fluorine-containing wastewater through the synergy of plasmon effect and defect engineering.
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OBJECTIVE: The objective of this study was to investigate the clinical efficacy and safety of treating sepsis patients with Xuebijing injection (XBJI). METHODS: We conducted a retrospective analysis of 418 patients who experienced severe infections and were treated with XBJI from June 2018 to June 2021. Propensity score matching was used to match the patient cases. The study population included 209 pairs of cases (418 individuals), and the analysis included data from before and after a 14-day course of treatment with carbapenem alone, or carbapenem with XBJI. RESULTS: There were no significant differences in the 14-day mortality or length of hospital stay (P > 0.05) between the two groups. The combined treatment group had more patients with C-reactive protein that returned to normal levels (compared to baseline) than the non-combined treatment group (14.4% vs 8.1%; odds ratio [OR]: 0.528; 95% confidence interval [CI]: 0.282-0.991; P = 0.026). Similarly, the combined treatment group had higher procalcitonin attainment rate (55.0% vs 39.7%; OR: 0.513; 95% CI: 0.346-0.759; P = 0.001) than the non-combined treatment group. Further, more patients in the combined treatment group achieved normal creatinine levels than in the non-combined treatment group (64.1% vs 54.1%; OR: 0.659; 95% CI: 0.445-0.975; P = 0.037). CONCLUSION: The combination of XBJI with carbapenem did not reduce the 14-day mortality rate of patients with severe infection, but it was able to reduce the level of inflammatory factors in patients with sepsis, and had a protective effect on liver and kidney function. Please cite this article as: Gong ZT, Yang HX, Zhu BB, Liu HH, Siri GL. Clinical efficacy of Xuebijing injection for the treatment of sepsis: A retrospective cohort study. J Integr Med. 2024; Epub ahead of print.
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AIM: To investigate the association between hemoglobin (Hb) levels and incident diabetic kidney disease (DKD) in patients with type 2 diabetes. METHODS: This retrospective cohort study included 1,657 patients with diabetes, without DKD at baseline, recruited from six clinics affiliated with Lee's United Clinic in Taiwan. Demographic data and laboratory results were collected and analyzed. Participants were stratified into quartiles based on their baseline Hb levels. A subgroup analysis was conducted specifically for patients with normal Hb levels (men: Hb ≥ 120 g/l, women: Hb ≥ 110 g/l). Cox regression analysis assessed the relation between Hb levels and incident DKD, adjusting for relevant covariates. RESULTS: Among the initial cohort, 93 (5.6%) had anemia at baseline. Over an average follow-up period of 5.7 ± 2.6 years, 594 patients (35.8%) developed DKD. Cox regression analysis revealed that, after adjusting for multiple variables, compared with patients in the highest quartile of baseline Hb levels (Q4: Hb ≥ 154 g/l), the hazard of DKD was 1.6 times higher in the lowest quartile (Q1: Hb ≤ 130 g/l) HR [95% CI] 1.58 [1.19-2.21] P < 0.001). In patients with normal Hb levels, Cox regression analysis also revealed that compared to the highest quartile (Q'4, Hb ≥ 154 g/l) the hazard of developing DKD was 1.3 times higher in the lowest quartile (Q'1, Hb ≤ 132 g/l): 81.29 [1.08;1.72] Pâ¯=â¯0.042. CONCLUSIONS: Lower Hb is associated with incident DKD, even in patients with normal Hb levels, independent of other risk factors.
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PURPOSE: The stimulator of interferon genes (STING) is a critical component of the innate immune system and plays a pivotal role in tumor immunotherapy. Developing non-invasive in vivo diagnostic methods for visualizing STING is highly valuable for STING-related immunotherapy. This work aimed to build a noninvasive imaging platform that can dynamically and quantitatively monitor tumor STING expression. METHODS: We investigated the in vivo positron emission tomography (PET) imaging of STING-expressing tumors (B16F10, MC38, and Panc02) with STING-targeted radioprobe ([18F]F-CRI1). The expression of STING in tumors was quantified, and correlation analysis was performed between these results and the outcomes of PET imaging. Furthermore, we optimized the structure of [18F]F-CRIn with polyethylene glycol (PEG) to improve the pharmacokinetic characteristics in vivo. A comprehensive comparison of the imaging and biodistribution results obtained with the optimized probes was conducted in the B16F10 tumors. RESULTS: The PET imaging results showed that the uptake of [18F]F-CRI1 in tumors was positively correlated with the expression of STING in tumors (r = 0.9184, P < 0.001 at 0.5 h). The lipophilicity of the optimized probes was significantly reduced. As a result of employing optimized probes, B16F10 tumor-bearing mice exhibited significantly improved tumor visualization in PET imaging, along with a marked reduction in retention within non-target areas such as the gallbladder and intestines. Biodistribution experiments further validated the efficacy of probe optimization in reducing uptake in non-target areas. CONCLUSION: In summary, this work demonstrated a promising pathway for the development of STING-targeted radioprobes, advancing in vivo PET imaging capabilities.
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Maternal immune activation (MIA) during pregnancy has been increasingly recognized as a critical factor in the development of neurodevelopmental disorders, with potential sex-specific impacts that are not yet fully understood. In this study, we utilized a murine model to explore the behavioral and molecular consequences of MIA induced by lipopolysaccharide (LPS) administration on embryonic day 12.5. Our findings indicate that male offspring exposed to LPS exhibited significant increases in anxiety-like and depression-like behaviors, while female offspring did not show comparable changes. Molecular analyses revealed alterations in pro-inflammatory cytokine levels and synaptic gene expression in male offspring, suggesting that these molecular disruptions may underlie the observed behavioral differences. These results emphasize the importance of considering sex as a biological variable in studies of neurodevelopmental disorders and highlight the need for further molecular investigations to understand the mechanisms driving these sex-specific outcomes. Our study contributes to the growing evidence that prenatal immune challenges play a pivotal role in the etiology of neurodevelopmental disorders and underscores the potential for sex-specific preventative approaches of MIA.
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Comportamento Animal , Modelos Animais de Doenças , Lipopolissacarídeos , Transtornos do Neurodesenvolvimento , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Gravidez , Camundongos , Masculino , Transtornos do Neurodesenvolvimento/imunologia , Transtornos do Neurodesenvolvimento/etiologia , Transtornos do Neurodesenvolvimento/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/imunologia , Comportamento Animal/efeitos dos fármacos , Citocinas/metabolismo , Ansiedade/imunologia , Fatores Sexuais , Depressão/imunologia , Caracteres Sexuais , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Glucose fluctuations may be involved in the pathophysiological process of cardiomyocyte apoptosis, but the exact mechanism remains elusive. This study focused on exploring the mechanisms related to glucose fluctuation-induced cardiomyocyte apoptosis. METHODS: Diabetic rats established via an injection of streptozotocin were randomized to five groups: the controlled diabetic (CD) group, the uncontrolled diabetic (UD) group, the glucose fluctuated diabetic (GFD) group, the GFD group rats with the injection of 0.9% sodium chloride (NaCl) (GFD + NaCl) and the GFD group rats with the injection of N-acetyl-L-cysteine (NAC) (GFD + NAC). Twelve weeks later, cardiac function and apoptosis related protein expressions were tested. Proteomic analysis was performed to further analyze the differential protein expression pattern of CD and GFD. RESULTS: The left ventricular ejection fraction levels and fractional shortening levels were decreased in the GFD group, compared with those in the CD and UD groups. Positive cells tested by DAB-TUNEL were increased in the GFD group, compared with those in the CD group. The expression of Bcl-2 was decreased, but the expressions of Bax, cleaved caspase-3 and cleaved caspase-9 were increased in response to glucose fluctuations. Compared with CD, there were 527 upregulated and 152 downregulated proteins in GFD group. Txnip was one of the differentially expressed proteins related to oxidative stress response. The Txnip expression was increased in the GFD group, while the Akt phosphorylation level was decreased. The interaction between Txnip and Akt was enhanced when blood glucose fluctuated. Moreover, the application of NAC partially reversed glucose fluctuations-induced cardiomyocyte apoptosis. CONCLUSIONS: Glucose fluctuations lead to cardiomyocyte apoptosis by up-regulating Txnip expression and enhancing Txnip-Akt interaction.
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Proteínas Reguladoras de Apoptose , Apoptose , Glicemia , Proteínas de Transporte , Diabetes Mellitus Experimental , Miócitos Cardíacos , Proteínas Proto-Oncogênicas c-akt , Ratos Sprague-Dawley , Transdução de Sinais , Animais , Miócitos Cardíacos/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Diabetes Mellitus Experimental/metabolismo , Masculino , Proteínas de Transporte/metabolismo , Glicemia/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Fosforilação , Função Ventricular Esquerda/efeitos dos fármacos , Tiorredoxinas/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/fisiopatologia , Cardiomiopatias Diabéticas/etiologia , Proteômica , Ratos , Mapas de Interação de Proteínas , Proteínas de Ciclo CelularRESUMO
Repeated exposure to word forms and meanings improves lexical knowledge acquisition. However, the roles of domain-general and language-specific brain regions during this process remain unclear. To investigate this, we applied intermittent theta burst stimulation over the domain-general (group left dorsolateral prefrontal cortex) and domain-specific (Group L IFG) brain regions, with a control group receiving sham intermittent theta burst stimulation. Intermittent theta burst stimulation effects were subsequently assessed in functional magnetic resonance imaging using an artificial word learning task which consisted of 3 learning phases. A generalized psychophysiological interaction analysis explored the whole brain functional connectivity, while dynamic causal modeling estimated causal interactions in specific brain regions modulated by intermittent theta burst stimulation during repeated exposure. Compared to sham stimulation, active intermittent theta burst stimulation improved word learning performance and reduced activation of the left insula in learning phase 2. Active intermittent theta burst stimulation over the domain-general region increased whole-brain functional connectivity and modulated effective connectivity between brain regions during repeated exposure. This effect was not observed when active intermittent theta burst stimulation was applied to the language-specific region. These findings suggest that the domain-general region plays a crucial role in word formation rule learning, with intermittent theta burst stimulation enhancing whole-brain connectivity and facilitating efficient information exchange between key brain regions during new word learning.
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Encéfalo , Idioma , Imageamento por Ressonância Magnética , Estimulação Magnética Transcraniana , Humanos , Masculino , Feminino , Adulto Jovem , Estimulação Magnética Transcraniana/métodos , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Adulto , Cognição/fisiologia , Mapeamento Encefálico , Aprendizagem/fisiologia , Ritmo Teta/fisiologia , Aprendizagem Verbal/fisiologia , Vias Neurais/fisiologiaRESUMO
Engineering acid-tolerant microbial strains is a cost-effective approach to overcoming acid stress during industrial fermentation. We previously constructed an acid-tolerant strain (Escherichia coli SC3124) with enhanced growth robustness and productivity under mildly acidic conditions by fine-tuning the expression of synthetic acid-tolerance module genes consisting of a proton-consuming acid resistance system (gadE), a periplasmic chaperone (hdeB), and ROS scavengers (sodB, katE). However, the precise acid-tolerance mechanism of E. coli SC3124 remained unclear. In this study, the growth of E. coli SC3124 under mild acid stress (pH 6.0) was determined. The final OD600 of E. coli SC3124 at pH 6.0 was 131% and 124% of that of the parent E. coli MG1655 at pH 6.8 and pH 6.0, respectively. Transcriptome analysis revealed the significant upregulation of the genes involved in oxidative phosphorylation, the tricarboxylic acid (TCA) cycle, and lysine-dependent acid-resistance system in E. coli SC3124 at pH 6.0. Subsequently, a weighted gene coexpression network analysis was performed to systematically determine the metabolic perturbations of E. coli SC3124 with mild acid treatment, and we extracted the gene modules highly associated with different acid traits. The results showed two biologically significant coexpression modules, and 263 hub genes were identified. Specifically, the genes involved in ATP-binding cassette (ABC) transporters, oxidative phosphorylation, the TCA cycle, amino acid metabolism, and purine metabolism were highly positively associated with mild acid stress responses. We propose that the overexpression of synthetic acid-tolerance genes leads to metabolic changes that confer mild acid stress resistance in E. coli. Integrated omics platforms provide valuable information for understanding the regulatory mechanisms of mild acid tolerance in E. coli and highlight the important roles of oxidative phosphorylation and ABC transporters in mild acid stress regulation. These findings offer novel insights to better the design of acid-tolerant chasses to synthesize value-added chemicals in a green and sustainable manner.
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Platelet extracellular vesicles (PEVs) play an important role in tumor development. However, the mechanisms underlying their biogenesis have not been fully elucidated. Protein kinase Cα (PKCα) is an important regulator of platelet activation, but the effect of PKCα on EV generation is unclear. We used small-particle flow cytometry and found that the number of PEVs was increased in patients with breast cancer compared to those with benign breast disease. This was accompanied by increased levels of activated PKCα in breast cancer platelets. Treating platelets with the PKCα agonist phorbol 12-myristate 13-acetate (PMA) increased the phosphorylation PKCα and induced PEV production, while the PKCα inhibitor GÖ6976 showed the opposite effects. Notably, incubating platelets from patients with benign tumors with the culture supernatant of MDA-MB-231 cells induced PKCα phosphorylation in the platelets. Mass spectrometry and coimmunoprecipitation assays showed that Dynamin 2 (DNM2), a member of the guanosine-triphosphate-binding protein family, might cooperate with activated PKCα to regulate PEV production by breast cancer platelets. Similar results were observed in a mouse model of lung metastasis. In addition, PEVs were engulfed by breast cancer cells and promoted cancer cell migration and invasion via miR-1297 delivery. These findings suggested that PKCα cooperates with DNM2 to induce PEV generation, and PEV release might triggered by factors in the breast cancer environment.
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Plaquetas , Neoplasias da Mama , Vesículas Extracelulares , Proteína Quinase C-alfa , Proteína Quinase C-alfa/metabolismo , Vesículas Extracelulares/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Humanos , Plaquetas/metabolismo , Feminino , Animais , Camundongos , Linhagem Celular Tumoral , Ativação Plaquetária , Metástase Neoplásica , Fosforilação , Movimento Celular , Acetato de Tetradecanoilforbol/farmacologiaRESUMO
Objectives: Chondrocyte metabolic dysfunction plays an important role in osteoarthritis (OA) development during aging and obesity. Protein post-translational modifications (PTMs) have recently emerged as an important regulator of cellular metabolism. We aim to study one type of PTM, lysine malonylation (MaK) and its regulator Sirt5 in OA development. Methods: Human and mouse cartilage tissues were used to measure SIRT5 and MaK levels. Both systemic and cartilage-specific conditional knockout mouse models were subject to high-fat diet (HFD) treatment to induce obesity and OA. Proteomics analysis was performed in Sirt5 -/- and WT chondrocytes. SIRT5 mutation was identified in the Utah Population Database (UPDB). Results: We found that SIRT5 decreases while MAK increases in the cartilage during aging. A combination of Sirt5 deficiency and obesity exacerbates joint degeneration in a sex dependent manner in mice. We further delineate the malonylome in chondrocytes, pinpointing MaK's predominant impact on various metabolic pathways such as carbon metabolism and glycolysis. Lastly, we identified a rare coding mutation in SIRT5 that dominantly segregates in a family with OA. The mutation results in substitution of an evolutionally invariant phenylalanine (Phe-F) to leucine (Leu-L) (F101L) in the catalytic domain. The mutant protein results in higher MaK level and decreased expression of cartilage ECM genes and upregulation of inflammation associated genes. Conclusions: We found that Sirt5 mediated MaK is an important regulator of chondrocyte cellular metabolism and dysregulation of Sirt5-MaK could be an important mechanism underlying aging and obesity associated OA development.
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Background: Myocardial inflammation and apoptosis induced by cirrhosis are among the primary mechanisms of cirrhotic cardiomyopathy. CD73, a common extracellular nucleotidase also known as 5'-nucleotidase, is associated with the progression of inflammation and immunity in multiple organs. However, the mechanism by which CD73 contributes to myocardial inflammation and apoptosis in cirrhosis remains unclear. Methods: In this study, a cirrhotic cardiomyopathy model in mice was established by bile duct ligation. Myocardial-specific overexpression of CD73 was achieved by tail vein injection of AAV9 (adeno-associated virus)-cTNT-NT5E-mCherry, and cardiac function in mice was assessed using echocardiography. Myocardial inflammation infiltration and apoptosis were evaluated through pathological observation and ELISA assays. The expression of CD73, A2AR, apoptotic markers, and proteins related to the NF-κB pathway in myocardial tissue were measured. Results: In the myocardial tissue of the cirrhotic cardiomyopathy mouse model, the expression of CD73 and A2AR increased. Overexpression of CD73 in the myocardium via AAV9 injection and stimulation of A2AR with CGS 21680 inhibited myocardial inflammation and cardiomyocyte apoptosis induced by cirrhosis. Additionally, overexpression of CD73 suppressed the activation of the NF-κB pathway by upregulating the expression of the adenosine receptor A2A. Conclusion: Our study reveals that the CD73/A2AR signaling axis mitigates myocardial inflammation and apoptosis induced by cirrhosis through negative feedback regulation of the NF-κB pathway.
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5'-Nucleotidase , Cardiomiopatias , Cirrose Hepática , Receptor A2A de Adenosina , Transdução de Sinais , Animais , Masculino , Camundongos , 5'-Nucleotidase/metabolismo , Apoptose , Cardiomiopatias/metabolismo , Cardiomiopatias/etiologia , Cardiomiopatias/imunologia , Modelos Animais de Doenças , Retroalimentação Fisiológica , Proteínas Ligadas por GPI , Cirrose Hepática/imunologia , Cirrose Hepática/metabolismo , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Receptor A2A de Adenosina/metabolismoRESUMO
The isolation and catalytic enantioselective synthesis of configurationally stable S-stereogenic sulfonium ylides has been a significant challenge in the field of asymmetric synthesis. These reactive intermediates are crucial for a variety of synthetic transformations, yet their inherent tendency towards rapid inversion at the sulfur stereocenter has hindered their practical utilization. Conventional approaches have focused on strategies that incorporate a C=S bond-containing cyclic framework to help mitigate this stereochemical lability. In this work, we present an alternative tactic that leverages the stabilizing influence of an adjacent N-atom and cyclic sulfide moiety. Exploiting a copper catalyzed enantioselective intermolecular carbene transfer reaction, structurally diverse S-stereogenic aminosulfonium ylides have been achieved in excellent yields and enantioselectivities. Experimental results indicate that the careful selection of 2-diazo-1,3-diketone precursors is crucial for achieving optimal stereoinduction in this transformation. The resulting highly enantioenriched aminosulfonium ylides allow for further stereospecific elaborations to furnish aminosulfonium ylide oxides and sulfinamide. This work expands the boundaries of chiral sulfonium ylide chemistry, providing access to a broad range of previously elusive S-stereogenic aminosulfonium ylide scaffolds.
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A digital workflow is presented for multiple transfers of targeted jaw relation and restorative spaces from interim to definitive restorations in patients with severe tooth wear. Following analysis of the targeted restorative space, segmented arch stereolithographic templates were digitally created and fabricated for precise control of reduction depth. Then, the jaw relation was transferred from the initially determined stabilization splint to the temporary fixed restoration and definitive restoration by using a digital articulator. This digital approach yielded a stabilized jaw relationship and restorative spaces transferring effect throughout successive stages of occlusal reconstruction resulting in satisfactory prosthetic outcomes.
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Polycyclic aromatic hydrocarbons (PAHs) are commonly found in various environmental matrices and have received significant attention due to their toxic effects on ecosystems and environmental health. In this study, a specific magnetic composite material derived from MXene, known as phenyl-functionalized NiFe2O4@Ti3C2TX, was designed and synthesized using a simple method. This composite material was used to develop an effective magnetic solid-phase extraction (MSPE) method for enriching trace polycyclic aromatic hydrocarbons (PAHs) in tea and coffee samples. The eluted PAHs were analyzed via gas chromatography-tandem mass spectrometry. Under optimal conditions, this method exhibited excellent linear relationships for 16 PAHs within the ranges of 0.001-25 and 0.0005-25 µg/L, with correlation coefficients exceeding 0.9979. The limits of detection for the target PAHs ranged from 0.1 to 0.3 ng/L. The effectiveness of the proposed method was evaluated by analyzing tea and coffee samples, and the satisfactory spiked recoveries of PAHs ranged from 84.5% to 112.6%.
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Café , Contaminação de Alimentos , Hidrocarbonetos Policíclicos Aromáticos , Extração em Fase Sólida , Chá , Chá/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/química , Café/química , Extração em Fase Sólida/métodos , Contaminação de Alimentos/análise , Níquel/química , Níquel/análise , Níquel/isolamento & purificação , Compostos Férricos/química , Cromatografia Gasosa-Espectrometria de Massas , Limite de DetecçãoRESUMO
The intricate processes that govern the interactions between peripatetic immune cells and distal renal injury in obesity are not fully understood. Employing transcriptomic analysis of circulating extracellular vesicles (EVs), a marked amplification of small RNA (miR-3960) is discerned within CD3-CD19+ B cells. This RNA is found to be preferentially augmented in kidney tissues, contrasting with its subdued expression in other organs. By synthesizing dual-luciferase reporter assay with co-immunoprecipitation analysis, it is pinpointed that miR-3960 specifically targets the nuclear gene TRMT5, a pivotal actor in the methylation of mitochondrial tRNA. This liaison instigates aberrations in the post-transcriptional modifications of mitochondrial tRNA, engendering deficiencies within the electron respiratory chain, primarily attributable to the diminution of the mitochondrial bioenergetic compound (NDUFA7) complex I. Such perturbations lead to a compromised mitochondrial respiratory capacity in renal tubular cells, thereby exacerbating tubular injury. In contrast, EV blockade or miR-3960 depletion markedly alleviates renal tubular injury in obesity. This investigation unveils a hitherto unexplored pathway by which obesity-induced circulating immune cells remotely manipulate mitochondrial metabolism in target organs. The strategic targeting of obese EVs or infiltrative immune cells and their specifically secreted RNAs emerges as a promising therapeutic avenue to forestall obesity-related renal afflictions.
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Modulating the electronic properties of transition metal sites in photocatalysts at the atomic level is essential for achieving high-activity carbon dioxide photoreduction (CO2PR). An electronic strategy is herein proposed to engineer In-d-band center of InVO4 by incorporating MnOx nanoparticles and oxygen vacancies (VO) into holey InVO4 nanobelts (MnOx/VO-InVO4), which synergistically modulates the In-d-band center to a moderate level and consequently leads to high-efficiency CO2PR. The MnOx/VO-InVO4 catalyst with optimized electronic property exhibits a single carbon evolution rate of up to 145.3 µmol g-1 h-1 and a carbon monoxide (CO) product selectivity of 92.6%, coming out in front of reported InVO4-based materials. It is discovered that the modulated electronic property favors the interaction between the In sites and their intermediates, which thereby improves the thermodynamics and kinetics of the CO2PR-to-CO reaction. This work not only demonstrates the effective engineering of the d orbital of the low-coordination In atoms to promote CO2PR, but also paves the way for the application of tuning d-band center to develop high-efficiency catalysts.
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Anthracenylidene is an intriguing structural unit with potential in various fields. The study presents a novel approach to introducing axial chirality into this all-carbon core skeleton through a remotely controlled desymmetrization strategy. A palladium-catalyzed enantioselective Heck arylation of exocyclic double bond of anthracene with two distinct substituents at the C10 position is harnessed to realize such a transformation. The judicious identification of the P-centrally chiral ligand is pivotal to ensure the competitive competence in reactivity and stereocontrol when the heteroatom handle is absent from the anthracenylidene skeleton. Both C10 mono- and disubstituted substrates were compatible for the established catalytic system, and structurally diverse anthracenylidene-based frameworks were forged with good-to-high enantiocontrol. The subsequent derivatization of the obtained products yielded a valuable array of centrally and axially chiral molecules, thus emphasizing the practicality of this chemistry. DFT calculations shed light on the catalytic mechanism and provided insights into the origin of the experimentally observed enantioselectivity for this reaction.
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Extracted from Platycodon grandiflorum, platycodon grandiflorum polysaccharides (PGPs) with diverse biological functions have been extensively employed for modification and fabrication of hydrogels for biomedical applications, such as wound dressings. However, since the lack of effective structural design, the reported polysaccharide-based hydrogel dressings are still suffered from structural failures and limited bio-functionality. Herein, we demonstrate a facile and general strategy to fabricate a supramolecular hydrogel composed of PGP-based polymer brush as building blocks combined with a Ca2+-mediated self-assembly process. The specific polymer brush with high branch functionality was achieved with polyacrylamide arms evenly grown on the PGP (grafting efficiency as high as 80 %) with series of chemical modifications. With above structural merits, the resulting hydrogel with densely crosslinked polymer brush featured enhanced mechanical strength as well as self-healing, and shear-thinning behaviors. Further biocompatible investigation indicated the as-prepared hydrogels with admirable performances in self-adhesion (adhesive strength of 16.7-79.5 kPa), a pH-responsive swelling ratio as high as 44 at pH 5.4, and pH-responsive degradation. They also showed antioxidant capacity by scavenging DPPH activity of nearly 80 % in 20 min, hemocompatibility, cell viability and cell migration. Impressively, the PGP-based polymer brush hydrogel served as a wound dressing revealed significant acceleration on wound closure.
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Bandagens , Hidrogéis , Polissacarídeos , Hidrogéis/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Humanos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Antioxidantes/química , Antioxidantes/farmacologia , Concentração de Íons de Hidrogênio , Animais , Polímeros/químicaRESUMO
Companionship refers to one's being in the presence of another individual. For adults, acquiring a new language is a highly social activity that often involves learning in the context of companionship. However, the effects of companionship on new language learning have gone relatively underexplored, particularly with respect to word learning. Using a within-subject design, the current study employs electroencephalography to examine how two types of companionship (monitored and co-learning) affect word learning (semantic and lexical) in a new language. Dyads of Chinese speakers of English as a second language participated in a pseudo-word-learning task during which they were placed in monitored and co-learning companionship contexts. The results showed that exposure to co-learning companionship affected the early attention stage of word learning. Moreover, in this early stage, evidence of a higher representation similarity between co-learners showed additional support that co-learning companionship influenced attention. Observed increases in delta and theta interbrain synchronization further revealed that co-learning companionship facilitated semantic access. In all, the similar neural representations and interbrain synchronization between co-learners suggest that co-learning companionship offers important benefits for learning words in a new language.