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Four new species of the genus Camptoscaphiella Caporiacco, 1934 are described from Xizang, China, i.e., C.metok Tong & Li, sp. nov. (â), C.shannan Tong & Li, sp. nov. (ââ), C.trifoliata Tong & Li, sp. nov. (ââ) and C.zayu Tong & Li, sp. nov. (ââ). Morphological descriptions, photographic illustrations and a distribution map of the four new species are given.
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BACKGROUND: Photoperiod sensitivity is among the most important agronomic traits of rice, as it determines local and seasonal adaptability and plays pivotal roles in determining yield and other key agronomic characteristics. By controlling the photoperiod, early-maturing rice can be cultivated to shorten the breeding cycle, thereby reducing the risk of yield losses due to unpredictable climate change. Furthermore, early-maturing and high-yielding rice needs to be developed to ensure food security for a rapidly growing population. Early-maturing and high-yielding rice should be developed to fulfill these requirements. OsCKq1 encodes the casein kinase1 protein in rice. OsCKq1 is a gene that is activated by photophosphorylation when Ghd7, which suppresses flowering under long-day conditions, is activated. RESULTS: This study investigates how OsCKq1 affects heading in rice. OsCKq1-GE rice was analyzed the function of OsCKq1 was investigated by comparing the expression levels of genes related to flowering regulation. The heading date of OsCKq1-GE lines was earlier (by about 3 to 5 days) than that of Ilmi (a rice cultivar, Oryza sativa spp. japonica), and the grain length, grain width, 1,000-grain weight, and yield increased compared to Ilmi. Furthermore, the culm and panicle lengths of OsCKq1-GE lines were either equal to or longer than those of Ilmi. CONCLUSIONS: Our research demonstrates that OsCKq1 plays a pivotal role in regulating rice yield and photoperiod sensitivity. Specifically, under long-day conditions, OsCKq1-GE rice exhibited reduced OsCKq1 mRNA levels alongside increased mRNA levels of Hd3a, Ehd1, and RFT1, genes known for promoting flowering, leading to earlier heading compared to Ilmi. Moreover, we observed an increase in seed size. These findings underscore OsCKq1 as a promising target for developing early-maturing and high-yielding rice cultivars, highlighting the potential of CRISPR/Cas9 technology in enhancing crop traits.
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Photocatalytic hydrogen production is one of the most valuable technologies in the future energy system. Here, we designed a metal-covalent organic frameworks (MCOFs) with both small-sized metal clusters and nitrogen-rich ligands, named COF-Cu3TG. Based on our design, small-sized metal clusters were selected to increase the density of active sites and shorten the distance of electron transport to active sites. While another building block containing nitrogen-rich organic ligands acted as a node that could in situ anchor metal atoms during photocatalysis and form interlayer single-atom electron bridges (SAEB) to accelerate electron transport. Together, they promoted photocatalytic performance. This represented the further utilization of Ru atoms and was an additional application of the photosensitizer. N2-Ru-N2 electron bridge (Ru-SAEB) was created in situ between the layers, resulting in a considerable enhancement in the hydrogen production rate of the photocatalyst to 10.47 mmol g-1 h-1. Through theoretical calculation and EXAFS, the existence position and action mechanism of Ru-SAEB were reasonably inferred, further confirming the rationality of the Ru-SAEB configuration. A sufficiently proximity between the small-sized Cu3 cluster and the Ru-SAEB was found to expedite electron transfer. This work demonstrated the synergistic impact of small molecular clusters with Ru-SAEB for efficient photocatalytic hydrogen production.
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The antiviral agent amantadine is frequently detected in seawater and marine organisms. Because of increasing concentrations, amantadine has become a contaminant of emerging concern. This compound has toxic effects on the brown algae Laminaria japonica. The effects of amantadine on the biological processes of L. japonica and the corresponding toxic mechanisms remain unclear. In this study, amantadine toxicity on L. japonica was investigated using histopathological and physiological characteristics combined with metabolomics analysis. Changes in metabolites were determined by untargeted metabolomics after exposure to 107 ng/L amantadine for 72 h. The catalase activity in the exposure group slightly increased, whereas the superoxide dismutase activity greatly decreased. An increase in the malondialdehyde concentration was observed after amantadine exposure, which suggested that lipid peroxidation and cell damage occurred. Metabolomics analysis showed that there were 406 differentially expressed metabolites after amantadine exposure. These were mainly phospholipids, amino acids, purines, and their derivatives. Inhibition of the glycerophospholipid metabolism affected the lipid bilayer and cell structure, which was aligned with changes in histological observation. Changes in amino acids led to perturbation of protein synthesis and induced oxidative stress through interference with glutathione metabolism and tyrosine metabolism. Amantadine also interfered with energy metabolism in L. japonica by disturbing the tricarboxylic acid cycle and purine metabolism. The results of this study provide new insights into the mechanism of amantadine toxicity on L. japonica.
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Carbon fiber (CF)-reinforced polymers (CFRPs) demonstrate potential for use in personal protective equipment. However, existing CFRPs are typically rigid, nonrecyclable, and lack of tearing resistance. In this study, flexible, recyclable, and tearing resistant polyurethane (PU)-CF composites are fabricated through complexation of reversibly cross-linked PU elastomer binders with CF fabrics. The PU-CF composites possess a high strength of 767 MPa and a record-high fracture energy of 2012 kJ m-2. The high performance of the PU-CF composites originates from the well-engineered PU elastomer binders that are obtained by cross-linking polytetrahydrofuran chains with in situ-formed nanodomains composed of hierarchical supramolecular interactions of hydrogen and coordination bonds. When subjected to tearing, the force concentrated on the damaged regions of the PU-CF composites can be effectively distributed to a wider area through the PU binders, leading to a significantly enhanced tearing resistance of the composites. The strong interfacial adhesion between PU binders and the CF fabrics enables the fracture of the CF in bundles, thereby significantly enhancing the strength and fracture energy of the composites. Because of the dynamic nature of the PU elastomer binders, the PU-CF composites can be recycled through the dissociation of the PU elastomer binders.
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Cancer is the most severe health problem facing most people today. Photodynamic therapy (PDT) for tumors has attracted attention because of its non-invasive nature, negligible adverse reactions, and high spatiotemporal selectivity. Developing biocompatible photosensitizers that can target, guide, and efficiently kill cancer cells is desirable in PDT. Here, two amphiphilic organic compounds, PS-I and PSS-II, were synthesized based on the D-π-A structure with a positive charge. The two AIEgens exhibited near-infrared emission, large Stokes shift, high 1O2 and O2-â generation efficiency, good biocompatibility, and photostability. They were co-incubated with cancer cells and eventually accumulated to lysosomes by cell imaging experiments. In vitro and in vivo experiments demonstrated that PS-I and PSS-II could effectively kill cancer cells and sufficiently inhibit tumor growth under light irradiation. PS-I had a higher fluorescence quantum yield in the aggregated state, which made it better for bio-imaging in imaging-guided photodynamic therapy. In contrast, PSS-II with a longer conjugated structure had more ROS generation to kill tumor cells under illumination, and the tumor growth inhibition of mice reached 71.95% during the treatment. No observable injury or undesirable outcomes were detected in the vital organs of the mice within the treatment group, suggesting that PSS-II/PS-I had a promising future in efficient imaging-guided PDT for cancer.
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Rayos Infrarrojos , Lisosomas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/síntesis química , Humanos , Animales , Ratones , Estructura Molecular , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Ensayos de Selección de Medicamentos Antitumorales , Diseño de Fármacos , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ratones Endogámicos BALB C , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Neoplasias Experimentales/diagnóstico por imagen , Supervivencia Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , FemeninoRESUMEN
The high level of tyrosinase leads to the generation of neuromelanin, further causing the abnormality of redox-related protein level and mediating the occurrence and development of Parkinson's disease (PD). However, the existing tyrosinase inhibitors are mostly natural product extracts or polyphenolic derivatives, which hindered them from penetrating the blood-brain barrier (BBB). Herein, we obtained a novel tyrosinase inhibitor, 2-06 (tyrosinase: monophenolase IC50 = 70.44 ± 22.69 µM, diphenolase IC50 = 1.89 ± 0.64 µM), through the structure-based screening method. The compound 2-06 presented good in vitro and in vivo safety, and can inhibit the tyrosinase and melanogenesis in B16F10. Moreover, this compound showed neuroprotective effects and Parkinsonism behavior improving function. 2-06 was proved to penetrate the BBB and enter the central nervous system (CNS). The exploration of the binding mode between 2-06 and tyrosinase provided the foundation for the subsequent structural optimization. This is the first research to develop a central-targeting tyrosinase inhibitor, which is crucial for in-depth study on the new strategy for utilizing tyrosinase inhibitors to treat PD.
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Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Inhibidores Enzimáticos , Monofenol Monooxigenasa , Enfermedad de Parkinson , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Animales , Relación Estructura-Actividad , Ratones , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Estructura Molecular , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/síntesis química , Humanos , Masculino , Simulación del Acoplamiento Molecular , Barrera Hematoencefálica/metabolismoRESUMEN
BACKGROUND: Combination therapy has emerged as the focus of research for unresectable hepatocellular carcinoma (HCC). In recent years, several studies have explored the clinical efficacy and safety of the combination therapies of transarterial chemoembolization (TACE) with tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs). AIM: To conduct an updated meta-analysis verifying the clinical benefits and adverse effects of the triple combination therapy for unresectable HCC. METHODS: All eligible cohort, non-randomized controlled, and randomized controlled trial studies from the PubMed, Web of Science, Embase, Cochrane Library, and MedLine databases up to March 20, 2024 were screened for the present meta-analysis. The study endpoints included complete response (CR), objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), and adverse events (AEs). Stata 16/18 software was used for this meta-analysis, and a P value of <0.05 was considered statistically significant. RESULTS: A total of 29 studies with 1754 patients were included. Among the patients who received the TACE therapy with TKIs and ICIs, the tumor response results revealed a pooled CR, ORR, and DCR of 14% [95%CI (0.11-0.18)], 61% [95%CI (0.55-0.66)], and 85% [95%CI (0.83-0.87)], respectively. In terms of the survival outcomes, the pooled median PFS and OS were 10.25 months [95%CI (9.31-11.18)] and 20.47 months [95%CI (18.98-21.97)], respectively. The pooled prevalence of all-grade AEs during the triple treatment was 90% [95%CI (0.84-0.94)] and that of grade ≥ 3 AEs was 32% [95%CI (0.24-0.42)]. CONCLUSION: The combination therapy of TACE, TKIs, and ICIs exhibits great clinical benefits for unresectable HCC in terms of tumor responses and survival outcomes without increasing the risk of severe AEs.
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The electrocatalytic methanol oxidation reaction (MOR) is a viable approach for realizing high value-added formate transformation from biomass byproducts. However, usually it is restricted by the excess adsorption of intermediates (COad) and overoxidation of catalysts, which results in low product selectivity and inactivation of the active sites. Herein, a novel Cu-O-Ni electron-transfer channel was constructed by loading NiCuO x on nickel foam (NF) to inhibit the overoxidation of Ni and enhance the formate selectivity of the MOR. The optimized NiCuO x -2/NF demonstrated excellent MOR catalytic performance at industrial current density (E 500 = 1.42 V) and high faradaic efficiency of â¼100%, as well as durable formate generation up to 600 h at â¼500 mA cm-2. The directional electron transfer from Cu to Ni and enhanced lattice stability could alleviate the overoxidation of Ni(iii) active sites to guarantee reversible Ni(ii)/Ni(iii) cycles and endow NiCuO x -2/NF with high stability under increased current density, respectively. An established electrolytic cell created by coupling the MOR with the hydrogen evolution reaction could produce H2 with low electric consumption (230 mV lower voltage at 400 mA cm-2) and concurrently generated the high value-added product of formate at the anode.
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Assembly of coordination networks from Cd(II) and a multi-interactive hexaazaphenalene-based ligand was successfully modulated using magnetic fields and thermodynamic control. A relatively weak field of only 320 mT was able to perturb the orientational distribution of the ligand in solution nudging the reaction down a different path. The underlying mechanism involved alignment of the ligands along the field lines, which was supported by DFT calculations. This crystallization technique could be extended to the synthesis of other networks and facilitate a deeper exploration of the reaction landscapes.
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PURPOSE: The objective of this meta-analysis was to evaluate the efficacy of administering preoperative oral carbohydrates (CHO) compared to a control treatment in improving postoperative recovery outcomes for patients undergoing laparoscopic cholecystectomy (LC). DESIGN: A meta-analysis of randomized controlled trials. METHODS: Through systematic searches in PubMed, Embase, and the Cochrane Library, randomized controlled trials focusing on preoperative oral carbohydrates for patients undergoing LC were collected. Data analysis was conducted using the Revman 5.3 software. FINDINGS: The meta-analysis incorporated 19 randomized studies, with a total of 1,568 participants. Meta-analysis results indicated that patients receiving CHO reported notably lower postoperative pain compared to those fasting (P = .006) or on placebo (P = .003). Furthermore, a significant reduction in preoperative hunger was observed in the CHO group compared to the controls (P = .002). A notable difference was also identified in the postoperative Homeostasis Model Assessment-IR changes between the CHO and control groups (P = .02). No significant variations were observed in thirst, postoperative nausea and vomiting, insulin level alterations, glucose level changes, duration of hospital stay, or recovery quality. CONCLUSIONS: Preoperative oral carbohydrates may alleviate hunger and pain, and attenuate postoperative insulin resistance more effectively than either overnight fasting or placebo in patients undergoing LC.
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Sensitive detection and efficient inactivation of pathogenic bacteria are crucial for halting the spread and reproduction of foodborne pathogenic bacteria. Herein, a novel Apt-modified PDMS-ZnO/Ag multifunctional biosensor has been developed for high-sensitivity surface-enhanced Raman scattering (SERS) detection along with photocatalytic sterilization towards Salmonella typhimurium (S. typhimurium). The distribution of the electric field in PDMS-ZnO/Ag with different Ag sputtering times was analyzed using a finite-difference time-domain (FDTD) algorithm. Due to the combined effect of electromagnetic enhancement and chemical enhancement, PDMS-ZnO/Ag exhibited outstanding SERS sensitivity. The limit of detection (LOD) for 4-MBA on the optimal SERS substrate (PZA-40) could be as little as 10-9 M. After PZA-40 was modified with the aptamer, the LOD of the PZA-40-Apt biosensor for detecting S. typhimurium was only 10 cfu/mL. Additionally, the PZA-40-Apt biosensor could effectively inactivate S. typhimurium under visible light irradiation within 10 min, with a bacterial lethality rate (Lb) of up to 97%. In particular, the PZA-40-Apt biosensor could identify S. typhimurium in food samples in addition to having minimal cytotoxicity and powerful biocompatibility. This work provides a multifunctional nanoplatform with broad prospects for selective SERS detection and photocatalytic sterilization of pathogenic bacteria.
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Técnicas Biosensibles , Salmonella typhimurium , Plata , Espectrometría Raman , Óxido de Zinc , Técnicas Biosensibles/métodos , Espectrometría Raman/métodos , Plata/química , Salmonella typhimurium/efectos de los fármacos , Óxido de Zinc/química , Óxido de Zinc/farmacología , Catálisis , Nanopartículas del Metal/química , Interacciones Hidrofóbicas e Hidrofílicas , Dimetilpolisiloxanos/química , Esterilización/métodos , Límite de DetecciónRESUMEN
Covalent-organic frameworks (COFs) with photoinduced donor-acceptor (D-A) radical pairs show enhanced photocatalytic activity in principle. However, achieving long-lived charge separation in COFs proves challenging due to the rapid charge recombination. Here, we develop a novel strategy by combining [6 + 4] nodes to construct zyg-type 3D COFs, first reported in COF chemistry. This structure type exhibits a fused Olympic-rings-like shape, which provides a platform for stabilizing the photoinduced D-A radical pairs. The zyg-type COFs containing catalytically active moieties such as triphenylamine and phenothiazine (PTZ) show superior photocatalytic production rates of hydrogen peroxide (H2O2). Significantly, the photochromic radical states of these COFs show up to 400% enhancement in photocatalytic activity compared to the parent states, achieving a remarkable H2O2 synthesis rate of 3324 µmol g-1 h-1, which makes the PTZ-COF one of the best crystalline porous photocatalysts in H2O2 production. This work will shed light on the synthesis of efficient 3D COF photocatalysts built on topologies that can facilitate photogenerating D-A radical pairs for enhanced photocatalysis.
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Increases in near-surface ozone (O3) concentrations is a global environmental problem. High-concentration O3 induces stress in plants, which can lead to visible damage to plants, reduced photosynthesis, accelerated aging, inhibited growth, and can even plant death. However, its impact has not been comprehensively evaluated because of the response differences between individual plant species, environmental O3 concentration, and duration of O3 stress in plants. We used a meta-analysis approach based on 31 studies 343 observations) to examine the effects of elevated O3 on malondialdehyde (MDA), superoxide dismutase (SOD), and peroxidase (POD) activities in herbaceous plants. Globally, important as they constitute the majority of the world's food crops. We partitioned the variation in effect size found in the meta-analysis according to the presence of plant species (ornamental herb, rice, and wheat), O3 concentration, and duration of O3 stress in plants. Our results showed that the effects of elevated O3 on plant membrane lipid peroxidation depending on plant species, O3 concentration, and duration of O3 stress in plants. The wheat SOD and POD activity was significantly lower compared to the herbs and rice (P<0.01). The SOD activity of all herbaceous plants increased by 34.6%, 10.5%, and 26.3% for exposure times to elevated O3 environments of 1-12, 13-30, and 31-60 days, respectively. When the exposure time was more than 60 days, SOD activity did not increase but significantly decreased by 12.1%. However, the POD activity of herbaceous plants increased by 30.4%, 57.3%, 21.9% and 5.81%, respectively, when exposure time of herbaceous plants in elevated O3 environment was 1-12, 13-30, 31-60 and more than 60 days. Our meta-analysis revealed that (1) rice is more resistant to elevated O3 than wheat and ornamental herbs likely because of the higher activity of antioxidant components (e.g., POD) in the symplasts, (2) exposure to elevated O3 concentrations for >60 days, may result in antioxidant SOD lose its regulatory ability, and the antioxidant component POD in the symplast is mainly used to resist O3 damage, and (3) the important factors affected the activity of SOD and POD in plants were not consistent: the duration of O3 stress in plants was more important than plant species and O3 concentration for SOD activity. However, for POD activity, plant species was the most important factor.
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Antioxidantes , Ozono , Superóxido Dismutasa , Superóxido Dismutasa/metabolismo , Antioxidantes/metabolismo , Malondialdehído/metabolismo , Peroxidación de Lípido , Plantas/metabolismo , Estrés Oxidativo , Oxidorreductasas/metabolismo , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Peroxidasa/metabolismoRESUMEN
Infectious bronchitis virus (IBV) is one of the most widely spread RNA viruses, causing respiratory, renal, and intestinal damage, as well as decreased reproductive performance in hens, leading to significant economic losses in the poultry industry. In this study, a new IBV strain designated as CK/CH/GX/LA/071423 was successfully isolated from the 60-day-old Three-Yellow chicken vaccinated with H120 and QXL87 vaccines. The complete genome sequence analysis revealed that the CK/CH/GX/LA/071423 strain shared a high similarity of 96.7% with the YX10 strain belonging to the GI-19 genotype. Genetic evolution analysis based on the IBV S1 gene showed that the CK/CH/GX/LA/071423 isolate belonged to the GI-19 genotype. Recombination analysis of the virus genome using RDP and Simplot software indicated that CK/CH/GX/LA/071423 was derived from recombination events between the YX10 and 4/91 vaccine strains, which was supported by phylogenetic analysis using gene sequences from the 3 regions. Furthermore, the S1 protein tertiary structure differences were observed between the CK/CH/GX/LA/071423 and the QXL87 and H120 vaccine strains. Pathogenicity studies revealed that the CK/CH/GX/LA/071423 caused death and led to pale and enlarged kidneys with abundant urate deposits, indicative of a nephropathogenic IBV strain. High virus titers were detected in the trachea, kidneys, and cecal tonsils, demonstrating broad tissue tropism. Throughout the experimental period, the virus positive rate in throat swabs of the infected group reached to 100%. These findings highlight the continued predominance of the QX genotype IBV in Guangxi of China and the ongoing evolution of different genotypes through genetic recombination, raising concerns about the efficacy of current IBV vaccines in providing effective protection to poultry.
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Pollos , Infecciones por Coronavirus , Genotipo , Virus de la Bronquitis Infecciosa , Filogenia , Enfermedades de las Aves de Corral , Virus de la Bronquitis Infecciosa/genética , Virus de la Bronquitis Infecciosa/patogenicidad , Animales , Enfermedades de las Aves de Corral/virología , Infecciones por Coronavirus/veterinaria , Infecciones por Coronavirus/virología , China , Virulencia , Recombinación Genética , Genoma ViralRESUMEN
Activated hepatic stellate cells (HSCs) have been widely recognized as a primary source of pathological myofibroblasts, leading to the accumulation of extracellular matrix and liver fibrosis. CD47, a transmembrane glycoprotein expressed on the surface of various cell types, has been implicated in non-alcoholic fatty liver disease. However, the precise role of CD47 in HSC activation and the underlying regulatory mechanisms governing CD47 expression remain poorly understood. In this study, we employed single-cell RNA sequencing analysis to investigate CD47 expression in HSCs from mice subjected to a high-fat diet. CD47 silencing in HSCs markedly inhibited the expression of fibrotic genes and promoted apoptosis. Mechanistically, we found that Yes-associated protein (YAP) collaborates with TEAD4 to augment the transcriptional activation of CD47 by binding to its promoter region. Notably, disruption of the interaction between YAP and TEAD4 caused a substantial decrease in CD47 expression in HSCs and reduced the development of high-fat diet-induced liver fibrosis. Our findings highlight CD47 as a critical transcriptional target of YAP in promoting HSC activation in response to a high-fat diet. Targeting the YAP/TEAD4/CD47 signaling axis may hold promise as a therapeutic strategy for liver fibrosis.
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To improve the color stability of anthocyanins (ACNs) in blueberry fermented beverage, the intermolecular copigmentation between ACNs and 3 different phenolic compounds, including (-)-epigallocatechin gallate (EGCG), ferulic acid (FA), and gallic acid (GA) as copigments, was compared in the model and the real blueberry fermented beverage, respectively. The copigmented ACNs by EGCG presented a high absorbance (0.34 a.u.) and redness (27.09 ± 0.17) in the model blueberry fermented beverage. The copigmentation by the participation of the 3 different phenolic compounds showed all a spontaneous exothermic reaction, and the Gibbs free energy (ΔG°) of the system was lowest (-5.90 kJ/mol) using EGCG as copigment. Furthermore, the molecular docking model verified that binary complexes formed between ACNs and copigments by hydrogen bonds and π-π stacking. There was a high absorbance (1.02 a.u.), percentage polymeric color (PC%, 68.3 %), and good color saturation (C*ab, 43.28) in the real blueberry fermented beverage aged for 90 days, and more malvidin-3-O-glucoside had been preserved in the wine using EGCG as copigment. This finding may guide future industrial production of blueberry fermented beverage with improved color.
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Antocianinas , Arándanos Azules (Planta) , Color , Ácidos Cumáricos , Fermentación , Ácido Gálico , Simulación del Acoplamiento Molecular , Fenoles , Antocianinas/química , Arándanos Azules (Planta)/química , Ácidos Cumáricos/química , Ácido Gálico/química , Ácido Gálico/análogos & derivados , Fenoles/análisis , Fenoles/química , Catequina/química , Catequina/análogos & derivados , Jugos de Frutas y Vegetales/análisis , Frutas/químicaRESUMEN
Alginate oligosaccharides (AOS), products of alginate degradation by endotype alginate lyases, possess favorable biological activities and have broad applications. Although many have been reported, alginate lyases with homogeneous AOS products and secretory production by an engineered host are scarce. Herein, the alginate lyase AlyC7 from Vibrio sp. C42 was characterized as a trisaccharide-producing lyase exhibiting high activity and broad substrate specificity. With PelB as the signal peptide and 500 mM glycine as the additive, the extracellular production of AlyC7 in Escherichia coli reached 1122.8 U/mL after 27 h cultivation in Luria-Bertani medium. The yield of trisaccharides from sodium alginate degradation by the produced AlyC7 reached 758.6 mg/g, with a purity of 85.1%. The prepared AOS at 20 µg/mL increased the root length of lettuce, tomato, wheat, and maize by 27.5%, 25.7%, 9.7%, and 11.1%, respectively. This study establishes a robust foundation for the industrial and agricultural applications of AlyC7.
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Escherichia coli , Polisacárido Liasas , Trisacáridos , Vibrio , Polisacárido Liasas/metabolismo , Trisacáridos/biosíntesis , Vibrio/enzimología , Especificidad por Sustrato , Alginatos , Zea mays , OligosacáridosRESUMEN
The application of electrochemical hydrogen evolution reaction (HER) for renewable energy conversion contributes to the ultimate goal of a zero-carbon emission society. Metal phosphides have been considered as promising HER catalysts in the alkaline environment, which, unfortunately, is still limited owing to the weak adsorption of H* and easy dissolution during operation. Herein, a bimetallic NiCoP-2/NF phosphide is constructed on nickel foam (NF), requiring rather low overpotentials of 150 mV and 169 mV to meet the current densities of 500 and 1000 mA cm-2, respectively, and able to operate stably for 100 h without detectable activity decay. The excellent HER performance is obtained thanks to the synergetic catalytic effect between Ni and Co, among which Ni is introduced to enhance the intrinsic activity and Co increases the electrochemically active area. Meanwhile, the protection of the externally generated amorphous phosphorus oxide layer improves the stability of NiCoP/NF. An electrolyser using NiCoP-2/NF as both cathode and anode catalysts in an alkaline solution can produce hydrogen with low electric consumption (overpotential of 270 mV at 500 mA cm-2).