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1.
Int J Biol Macromol ; 278(Pt 1): 134674, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39134193

RESUMO

The fascinating role of SPRR3 in various malignant tumors has prompted extensive research to unravel its expression patterns and prognostic significance. To comprehensively investigate SPRR3, we leveraged multiple datasets containing invaluable biomedical information, specifically focusing on the comparative analysis of SPRR3 gene expression levels across different cancer types. Meticulous examination of lung adenocarcinoma allowed us to delve deeper into the correlation between SPRR3 expression and its molecular biological functions. Our comprehensive analysis encompassed 33 malignant tumors, and the results unveiled significant differential expression of SPRR3 across a range of malignancies. Moreover, this aberrant expression of SPRR3 was observed to be closely associated with poorer prognosis in these malignant tumors. Notably, our investigation also unearthed a compelling link between SPRR3 and immune infiltrating cells in lung adenocarcinoma. The utilization of receiver operating characteristic (ROC) curves and survival curves in our study illustrated the immense potential of SPRR3 as a highly accurate predictor of cancer. These findings further emphasize the possibility of SPRR3 serving as a promising diagnostic and prognostic biomarker for a diverse array of cancers.

2.
Imeta ; 3(4): e211, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39135687

RESUMO

The life cycle of genome builds spans interlocking pillars of assembly, annotation, and comparative genomics to drive biological insights. While tools exist to address each pillar separately, there is a growing need for tools to integrate different pillars of a genome project holistically. For example, comparative approaches can provide quality control of assembly or annotation; genome assembly, in turn, can help to identify artifacts that may complicate the interpretation of genome comparisons. The JCVI library is a versatile Python-based library that offers a suite of tools that excel across these pillars. Featuring a modular design, the JCVI library provides high-level utilities for tasks such as format parsing, graphics generation, and manipulation of genome assemblies and annotations. Supporting genomics algorithms like MCscan and ALLMAPS are widely employed in building genome releases, producing publication-ready figures for quality assessment and evolutionary inference. Developed and maintained collaboratively, the JCVI library emphasizes quality and reusability.

3.
Nat Plants ; 10(8): 1184-1200, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-39103456

RESUMO

Scaffolding is crucial for constructing most chromosome-level genomes. The high-throughput chromatin conformation capture (Hi-C) technology has become the primary scaffolding strategy due to its convenience and cost-effectiveness. As sequencing technologies and assembly algorithms advance, constructing haplotype-resolved genomes is increasingly preferred because haplotypes can provide additional genetic information on allelic and non-allelic variations. ALLHiC is a widely used allele-aware scaffolding tool designed for this purpose. However, its dependence on chromosome-level reference genomes and a higher chromosome misassignment rate still impede the unravelling of haplotype-resolved genomes. Here we present HapHiC, a reference-independent allele-aware scaffolding tool with superior performance on chromosome assignment as well as contig ordering and orientation. In addition, we provide new insights into the challenges in allele-aware scaffolding by conducting comprehensive analyses on various adverse factors. Finally, with the help of HapHiC, we constructed the haplotype-resolved allotriploid genome for Miscanthus × giganteus, an important lignocellulosic bioenergy crop.


Assuntos
Cromossomos de Plantas , Genoma de Planta , Haplótipos , Cromossomos de Plantas/genética , Cromatina/genética , Poaceae/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Alelos
4.
Adv Mater ; : e2407974, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39152929

RESUMO

Dual-atom catalysts (DACs) with atomically dispersed dual-sites, as an extension of single-atom catalysts (SACs), have recently become a new hot topic in heterogeneous catalysis due to their maximized atom efficiency and dual-site diverse synergy, because the synergistic diversity of dual-sites achieved by asymmetric microenvironment tailoring can efficiently boost the catalytic activity by optimizing the electronic structure of DACs. Here, this work first summarizes the frequently-used experimental synthesis and characterization methods of DACs. Then, four synergistic catalytic mechanisms (cascade mechanism, assistance mechanism, co-adsorption mechanism and bifunction mechanism) and four key modulating methods (active site asymmetric strategy, transverse/axial-modification engineering, distance engineering and strain engineering) are elaborated comprehensively. The emphasis is placed on the effects of asymmetric microenvironment of DACs on oxygen/carbon dioxide reduction reaction. Finally, some perspectives and outlooks are also addressed. In short, the review summarizes a useful asymmetric microenvironment tailoring strategy to speed up synthesis of high-performance electrocatalysts for different reactions.

5.
Langmuir ; 40(26): 13688-13698, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38902198

RESUMO

The structure-property relationship of poly(vinyl chloride) (PVC)/CaCO3 nanocomposites is investigated by all-atom molecular dynamics (MD) simulations. MD simulation results indicate that the dispersity of nanofillers, interfacial bonding, and chain mobility are imperative factors to improve the mechanical performance of nanocomposites, especially toughness. The tensile behavior and dissipated work of the PVC/CaCO3 model demonstrate that 12 wt % CaCO3 modified with oleate anion and dodecylbenzenesulfonate can impart high toughness to PVC due to its good dispersion, favorable interface interaction, and weak migration of PVC chains. Under the guidance of MD simulation, we experimentally prepared a transparent PVC/CaCO3 nanocomposite with good mechanical properties by in situ polymerization of monodispersed CaCO3 in vinyl chloride monomers. Interestingly, experimental tests indicate that the optimum toughness of a nanocomposite (a 368% increase in the elongation at break and 204% improvement of the impact strength) can be indeed realized by adding 12 wt % CaCO3 modified with oleic acid and dodecylbenzenesulfonic acid, which is remarkably consistent with the MD simulation prediction. In short, this work provides a proof-of-concept of using MD simulation to guide the experimental synthesis of PVC/CaCO3 nanocomposites, which can be considered as an example to develop other functional nanocomposites.

6.
Cell Commun Signal ; 22(1): 303, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831321

RESUMO

BACKGROUND: While previous studies have primarily focused on Glucose transporter type 1 (GLUT1) related glucose metabolism signaling, we aim to discover if GLUT1 promotes tumor progression through a non-metabolic pathway. METHODS: The RNA-seq and microarray data were comprehensively analyzed to evaluate the significance of GLUT1 expression in lung adenocarcinoma (LUAD). The cell proliferation, colony formation, invasion, and migration were used to test GLUT1 's oncogenic function. Co-immunoprecipitation and mass spectrum (MS) were used to uncover potential GLUT1 interacting proteins. RNA-seq, DIA-MS, western blot, and qRT-PCR to probe the change of gene and cell signaling pathways. RESULTS: We found that GLUT1 is highly expressed in LUAD, and higher expression is related to poor patient survival. GLUT1 knockdown caused a decrease in cell proliferation, colony formation, migration, invasion, and induced apoptosis in LUAD cells. Mechanistically, GLUT1 directly interacted with phosphor-epidermal growth factor receptor (p-EGFR) and prevented EGFR protein degradation via ubiquitin-mediated proteolysis. The GLUT1 inhibitor WZB117 can increase the sensitivity of LUAD cells to EGFR-tyrosine kinase inhibitors (TKIs) Gefitinib. CONCLUSIONS: GLUT1 expression is higher in LUAD and plays an oncogenic role in lung cancer progression. Combining GLUT1 inhibitors and EGFR-TKIs could be a potential therapeutic option for LUAD treatment.


Assuntos
Adenocarcinoma de Pulmão , Proliferação de Células , Receptores ErbB , Transportador de Glucose Tipo 1 , Neoplasias Pulmonares , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 1/genética , Humanos , Receptores ErbB/metabolismo , Receptores ErbB/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Fosforilação , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Ligação Proteica , Apoptose , Estabilidade Proteica
7.
J Org Chem ; 89(11): 7630-7643, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38738853

RESUMO

Atropoisomeric chemotypes of diaryl ethers-related scaffolds are prevalent in naturally active compounds. Nevertheless, there remains considerable research to be carried out on the catalytic asymmetric synthesis of these axially chiral molecules. In this instance, we disclose an N-heterocyclic carbene (NHC)-catalyzed synthesis of axially chiral diaryl ethers via atroposelective esterification of dialdehyde-containing diaryl ethers. NHC desymmetrization produces axially chiral diaryl ether atropisomers with high yields and enantioselectivities in moderate circumstances. Chiral diaryl ether compounds may be precursors for highly functionalized diaryl ethers with bioactivity and chiral ligands for asymmetric catalysis.

8.
Langmuir ; 40(17): 9134-9143, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38636482

RESUMO

Wound healing has been a persistent clinical challenge for a long time. Electrical stimulation is an effective therapy with the potential to accelerate wound healing. In this work, the self-powered electrospun nanofiber membranes (triples) were constructed as multifunctional wound dressings with electrical stimulation and biochemical capabilities. Triple was composed of a hydrolyzable inner layer with antiseptic and hemostatic chitosan, a hydrophilic core layer loaded with conductive AgNWs, and a hydrophobic outer layer fabricated by self-powered PVDF. Triple exhibited presentable wettability and acceptable moisture permeability. Electrical performance tests indicated that triple can transmit electrical signals formed by the piezoelectric effect to the wound. High antibacterial activities were observed for triple against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, with inhibition rates of 96.52, 98.63, and 97.26%, respectively. In vitro cell assays demonstrated that triple cells showed satisfactory proliferation and mobility. A whole blood clotting test showed that triple can enhance hemostasis. The innovative self-powered multifunctional fibers presented in this work offer a promising approach to addressing complications and expediting the promotion of chronic wound healing.


Assuntos
Antibacterianos , Escherichia coli , Nanofibras , Pseudomonas aeruginosa , Staphylococcus aureus , Cicatrização , Cicatrização/efeitos dos fármacos , Nanofibras/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Quitosana/química , Humanos , Animais , Proliferação de Células/efeitos dos fármacos
9.
Bioinformatics ; 40(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38547397

RESUMO

MOTIVATION: Constructing a phylogenetic tree requires calculating the evolutionary distance between samples or species via large-scale resequencing data, a process that is both time-consuming and computationally demanding. Striking the right balance between accuracy and efficiency is a significant challenge. RESULTS: To address this, we introduce a new algorithm, MIKE (MinHash-based k-mer algorithm). This algorithm is designed for the swift calculation of the Jaccard coefficient directly from raw sequencing reads and enables the construction of phylogenetic trees based on the resultant Jaccard coefficient. Simulation results highlight the superior speed of MIKE compared to existing state-of-the-art methods. We used MIKE to reconstruct a phylogenetic tree, incorporating 238 yeast, 303 Zea, 141 Ficus, 67 Oryza, and 43 Saccharum spontaneum samples. MIKE demonstrated accurate performance across varying evolutionary scales, reproductive modes, and ploidy levels, proving itself as a powerful tool for phylogenetic tree construction. AVAILABILITY AND IMPLEMENTATION: MIKE is publicly available on Github at https://github.com/Argonum-Clever2/mike.git.


Assuntos
Algoritmos , Filogenia , Simulação por Computador , Análise de Sequência de DNA
10.
Transl Lung Cancer Res ; 13(1): 95-111, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38404999

RESUMO

Background: At present, there is a lack of studies in invasive mucinous adenocarcinoma (IMA) that combine clinicopathological and imaging features to stratify risk and select optimal treatment regimen. We aimed to develop and validate a nomogram for predicting recurrence-free survival (RFS) and identifying adjuvant chemotherapy (ACT) beneficiaries for completely resected stage I primary IMA. Methods: This retrospective study included 750 patients from three hospitals. Patients from two hospitals were divided into training (n=424) and validating cohort (n=185), and patients from the remaining other one hospital constituted external test cohort (n=141) and preoperative computed tomography (CT) image features of each patient were consecutively evaluated. The nomogram was developed by integrating significant prognostic factors of RFS identified in the multivariate analysis. The risk score (RS) based on nomogram was calculated in the entire cohort and the optimal cut-off point for risk stratification was obtained by X-tile software. The Kaplan-Meier method, log-rank test and interaction were used to evaluate the difference in RFS and overall survival (OS) between different risk and treatment groups. Results: Visceral pleural invasion (VPI, P<0.001), lymph-vascular invasion (LVI, P<0.001), tumor size (P<0.001), smoking history (P<0.001), lobulation (P<0.001) were identified as independent prognostic factors for RFS. The concordance index (C-index) of the nomogram was higher than that of tumor-node-metastasis (TNM) staging system (validation cohort: 0.73±0.09 vs. 0.62±0.08, P<0.001; external test cohort: 0.74±0.10 vs. 0.70±0.09, P=0.035). The patients with higher RS were associated with worse RFS [hazard ratios (HRs) ≥4.76] and OS (HRs ≥2.55) in all included cohorts. Chemotherapy benefits in terms of RFS and OS were observed for patients in higher RS group in both stage IB (interaction P=0.012 for RFS and P=0.037 for OS) and stage I IMA (interaction P<0.001 for both RFS and OS). Conclusions: The nomogram based on CT image and clinicopathologic features showed superior performance in predicting RFS for stage I IMA and might identify ACT candidates for personalized patient treatment.

11.
Small ; 20(27): e2311335, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38286638

RESUMO

Modulating the chemical composition and structure has been considered as one of the most promising strategies for developing high-efficient water splitting catalysts. Here, a single-atom Ru doped Ni2P/Fe3P catalyst is synthesized by introducing the dispersed Ru atoms to adjust Ni2P/Fe3P heterostructure. Single atom Ru provides effective hydrogen evolution reaction (HER) active sites for boosting catalytic activities. The catalyst with only 0.2 wt.% content of Ru exhibits an overpotential of 19.3 mV at 10 mA cm-2, which is obviously lower than 146.1 mV of Ni2P/Fe3P. Notably, an alkaline overall water electrolyzer based on Ru-Ni2P/Fe3P catalysts achieves a cell voltage of 1.47 V and operates over 600 h at 10 mA cm-2, which is superior to that of benchmark RuO2//Pt/C (1.61 V). The theoretical calculations further confirm that Ru single atom doping can effectively optimize the hydrogen/water adsorption free energy of the active site and therefore improve the HER activity of heterostructure. This work provides a valuable reference to design high-activity and durability catalyst for water splitting through the double modulation of interface-effect and atomic doping.

12.
ACS Appl Mater Interfaces ; 16(1): 784-794, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38165077

RESUMO

Highly crystalline carbon nitride (CCN), benefiting from the reduced structural imperfections, enables improved electron-hole separation. Yet, the crystalline phase with insufficient inherent defects suffers from a poor performance toward the reaction intermediate adsorption with respect to the amorphous phase. Herein, a crystalline-amorphous carbon nitride (CACN) with an isotype structure was constructed via a two-step adjacent calcination strategy. Through specific oxygen etching and crystallization, the formation of a built-in electric field at the interface could drive charge transfer and separation, thus promoting photoredox reaction. As expected, the optimized CACN exhibited a H2O2 generation efficiency as high as 2.15 mM gcat-1 h-1, paired with a promoted pollutant degradation efficiency, which outperform its crystalline (CCN) and amorphous [amorphous carbon nitride (ACN)] counterparts. The detailed electron/hole transportation via a built-in electronic field and free radical formation based on the enhanced adsorption of oxygen were considered, and the synchronous reaction pathway was carried out. This work paves a novel pathway for the synthesis of carbon nitride with an isotype structure from the perspective of interfacial engineering.

13.
J Cancer ; 14(17): 3238-3247, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928427

RESUMO

Chaperonins, which contain t-complex polypeptide 1 (CCT), are critical for correct protein folding to generate stable and functional protein conformations, which are important for cell growth and survival. However, little is known about the expression and prognostic significance of CCT8 (subunit 8 of the CCT complex chaperonin) in lung cancer. In this study, we demonstrated that CCT8 expression is frequently increased in human lung cancer. Survival analysis indicated that CCT8 expression is closely correlated with inferior overall survival in lung adenocarcinoma (LUAD), but not in lung squamous carcinoma (LUSC). Subsequently, ectopic expression of CCT8 facilitated cell migration and tumor metastasis, and vice versa. Mechanistically, CCT8 interacted and activated ATK. Inhibition of AKT suppressed CCT8-induced cell migration and tumor metastasis. Our findings support CCT8 as a biomarker for LUAD prognosis and as a target for LUAD therapy.

14.
Cancer Biomark ; 38(2): 177-189, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545214

RESUMO

BACKGROUND: It has been discovered that lncRNA ARAP1-AS1 is upregulated and operates as a tumor promoter in many cancers. However, its pattern of expression and potential mechanism in lung adenocarcinoma (LUAD) is still unknown. METHODS: The levels of lncRNA ARAP1-AS1, miR-8068, and CEACAM5 expressions in LUAD cell lines and tissues were assessed by conducting western blot and RT-qPCR analyses. MiR-8068's potential targeting relationships with lncRNA ARAP1-AS1 and CEACAM5 were ascertained by performing bioinformatics analysis. The interaction of lncRNA ARAP1-AS1 with miR-8068 was validated by means of by RIP and luciferase reporter experiments. CCK-8, cell adhesion, and Transwell migration experiments were conducted to study how lncRNA ARAP1-AS1 affects LUAD cell migration, adhesion, and proliferation. To confirm the function of lncRNA ARAP1-AS1 in vivo, a tumor formation experiment was executed. RESULTS: An elevated expression of lncRNA ARAP1-AS1 was observed among the LUAD cells and tissues. The overexpression of lncRNA ARAP1-AS boosted cell proliferation, adhesion, and migration in LUAD and also favored in vivo tumor growth. MiR-8068 was found to be lncRNA ARAP1-AS1's target gene. MiR-8068 overexpression partially antagonized lncRNA ARAP1-AS1's promotive effect on proliferation, viability, and adhesion. Meanwhile CEACAM5 could alleviate the miR-8068-induced inhibition of tumor growth. The negative correlation of miR-8068 with lncRNA ARAP1-AS1 or CEACAM5 was also revealed. CONCLUSION: To upregulate CEACAM5 expression lncRNA ARAP1-AS1 targeted miR-8068, thus promoting the progression of LUAD. This indicates that the lncRNA ARAP1-AS1/miR-8068/CEACAM5 axis has potential as a therapeutic target in LUAD treatment.

15.
Anal Chim Acta ; 1272: 341497, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37355331

RESUMO

The highly efficient and accurate recognition of targeted allergens is an essential element in the diagnosis of allergic diseases and follow-up desensitization treatment in clinic. The current clinical methods widely used to detect sIgE are high cost, time-consuming procedures, and bulky equipment. Herein, a multiplex microfluidic paper-based device (multi-µPAD) was developed that combined with tailored gold nanoparticles for simultaneously visual, colorimetric detection of different allergens in serum. This device could be used as quantitative detection of sIgE with LOD as low as 0.246 KUA/L in colorimetric method. In vitro results also showed that this device possessed good repeatability, high accuracy and incredible stability in different pH (6.0-7.4) and temperature (24-37 °C), as well as long-term storage within 90-day. Finally, this method was successfully utilized for assessing clinical multi-sample screening in 35 allergic patients. After the addition of the samples from allergic patients, the agreement rate of clinical results with commercial enzyme-linked immunosorbent assay (ELISA) kit reached more than 97%, which further indicated that this device had the advantages of efficient, accurate and sensitive to screen various allergens in real clinical serum samples. Therefore, by simply altering antigens and antibodies, this device can also be used for high-throughput detection of other allergens, making it considerable potential for clinical diagnosis of allergic diseases.


Assuntos
Alérgenos , Nanopartículas Metálicas , Humanos , Alérgenos/análise , Ouro , Colorimetria , Microfluídica , Imunoglobulina E
16.
J Org Chem ; 88(11): 6633-6644, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37133412

RESUMO

Pyranones have raised great concerns owing to their considerable applications in a variety of sectors. However, the development of direct asymmetric allylation of 4-hydroxypyran-2-ones is still restricted. Herein, we present an effective iridium-catalyzed asymmetric functionalization technique for the synthesis of 4-hydroxypyran-2-one derivatives over direct and efficient catalytic asymmetric Friedel-Crafts-type allylation by using allyl alcohols. The allylation products could be obtained with good to high yields (up to 96%) and excellent enantioselectivities (>99% ee). Therefore, the disclosed technique provides a new asymmetric synthetic strategy to explore pyranone derivatives in depth, thus providing an interesting approach for global application and further utilization in organic synthesis and pharmaceutical chemistry.

17.
Eur J Clin Invest ; 53(4): e13929, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36453878

RESUMO

BACKGROUND: Oesophageal carcinoma (EC) is one of the types of prevalent malignant cancer in the globe. Many researchers reported the vital role played by long-coding RNAs in EC. In the current research, we investigated the mechanisms of the action of lncRNA BBOX1-AS1 in EC progression. METHODS: In EC tissues and EC cells, the expression levels of miR-361-3p along with COL1A1 and BBOX1-AS1 were detected through RT-qPCR or western blotting. MiR-361-3p interactions with BBOX1-AS1 or COL1A1 were verified through Luciferase reporter and RIP tests. Loss of function combined with caspase-3 activity, CCK-8 and Transwell assays was performed to investigate cell apoptosis, proliferation and migration, respectively. Knockdown of BBOX1-AS1 was used for evaluating BBOX1-AS1 effects on tumour development in vivo. RESULTS: BBOX1-AS1 was remarkably elevated in EC tissues and cells. In addition, the silencing of BBOX1-AS1 attenuated the cell viability, cell migration and enhanced cell apoptosis of EC, as well as suppressed EC tumour formation in vivo. Moreover, BBOX1-AS1 was found to be a sponge of miR-361-3p, which downregulated miR-361-3p expression. MiR-361-3p inhibitor rescued the anti-tumour effect of BBOX1-AS1 knockdown on the progression of EC. Furthermore, we discovered that miR-361-3p specially bound to COL1A1 3'UTR and downregulated COL1A1 and COL1A1 reduction declined the promoting effect of silencing miR-361-3p on EC cell malignant phenotypes. CONCLUSION: BBOX1-AS1 facilitated the EC development and malignancy via miR-361-3p/COL1A1 axis, indicating BBOX1-AS1 could be a novel therapy target for the diagnostic of EC.


Assuntos
Neoplasias Esofágicas , MicroRNAs , RNA Longo não Codificante , Humanos , Apoptose , Western Blotting , Movimento Celular , Proliferação de Células , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica
18.
Angew Chem Int Ed Engl ; 62(7): e202216534, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36536515

RESUMO

Diaryl ethers are widespread in biologically active compounds, ligands and catalysts. It is known that the diaryl ether skeleton may exhibit atropisomerism when both aryl rings are unsymmetrically substituted with bulky groups. Despite recent advances, only very few catalytic asymmetric methods have been developed to construct such axially chiral compounds. We describe herein a dynamic kinetic resolution approach to axially chiral diaryl ethers via a Brønsted acid catalyzed atroposelective transfer hydrogenation (ATH) reaction of dicarbaldehydes with anilines. The desired diaryl ethers could be obtained in moderate to good chemical yields (up to 79 %) and high enantioselectivities (up to 95 % ee) under standard reaction conditions. Such structural motifs are interesting precursors for further transformations and may have potential applications in the synthesis of chiral ligands or catalysts.

19.
Small ; 18(48): e2204720, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36269882

RESUMO

Enhancing the catalytic activity of Pt-based alloy by a rational structural design is the key to addressing the sluggish kinetics of direct alcohol fuel cells. Herein, a facile one-pot method is reported to synthesize PtCuRu nanoflowers (NFs). The synergetic effect among Pt, Cu, and Ru can lower the d-band center of Pt, regulate the morphology, generate Ru-rich edge, and allow the exposure of more high index facets. The optimized Pt0.68 Cu0.18 Ru0.14 NFs exhibit outstanding electrocatalytic performances and excellent anti-poisoning abilities. The specific activities for the methanol oxidation reaction (MOR) (7.65 mA cm-2 ) and ethanol oxidation reaction (EOR) (7.90 mA cm-2 ) are 6.0 and 7.1 times higher than commercial Pt/C, respectively. The CO stripping experiment and the chronoamperometric (5000 s) demonstrate the superior anti-poisoning property and durability performance. Density functional theory calculations confirm that high metallization degree leads to the decrease of d-band center, the promotion of oxidation of CO, and improvement of the inherent activity and anti-poisoning ability. A Ru-rich edge exposes abundant high index facets to accelerate the reaction kinetics of rate-determining steps by decreasing the energy barrier for forming *HCOOH (MOR) and CC bond breaking (EOR).


Assuntos
Ligas , Etanol , Cinética
20.
Oxid Med Cell Longev ; 2022: 3521971, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225178

RESUMO

Background: It has been found that miR-505-5p is closely related to cardiovascular metabolic risk factors. Nonetheless, there is little research analyzing miR-505-5p for its role as well as molecular mechanism in myocardial injury caused by ischemia-reperfusion (I/R). Methods: This work utilized quantitative reverse transcriptase PCR (qRT-PCR) for detecting miR-505-5p and serum uromodulin (sUmod) levels. sUmod, interleukin-1beta (IL-1ß), IL-6, IL-10, caspase7, caspase9, tumor necrosis factor-alpha (TNF-α), Bax, and Bcl-xL expression was detected by western blot. Bioinformatics database was used for target prediction and miR-505-5's target was determined by luciferase reporter gene assay. Results: Relative to sham group, sUmod was highly expressed within myocardial I/R injury (MIRI), whereas sUmod silencing significantly decreased the heart weight/body weight ratio, reduced serum myocardial enzymes expression, ameliorated I/R-mediated myocardial apoptosis, and inflammation. TargetScan bioinformatics database and luciferase reporter genes confirmed that sUmod was miR-505-5p's direct target gene, besides, miR-505-5p overexpression significantly improved the myocardial injury score, increased IL-10, decreased TNF-α, IL-1ß, IL-6 expression, decreased caspase7, caspase9, Bax expression, and increased Bcl-xL expression. More importantly, overexpression of sUmod abolished miR-505-5p overexpression's role in I/R-mediated myocardial apoptosis and inflammation. Conclusion: miR-505-5p can improve I/R-mediated myocardial apoptosis and inflammation by targeting sUmod. In this study, miR-505-5p is related to MIRI pathogenesis, which provides the new possible targeted therapy in patients with MIRI.


Assuntos
MicroRNAs , Miocardite , Apoptose/genética , Humanos , Inflamação/genética , Interleucina-10 , Interleucina-1beta/farmacologia , Interleucina-6 , Isquemia , MicroRNAs/metabolismo , Reperfusão , Fator de Necrose Tumoral alfa/farmacologia , Uromodulina/farmacologia , Proteína X Associada a bcl-2
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