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1.
Artículo en Inglés | MEDLINE | ID: mdl-39208603

RESUMEN

Magnolia bark is a traditional Chinese medicine used for hypoglycaemia. With the widespread use of Magnolia bark, its resources are facing a serious shortage. To address this issue, a strategy based on high-coverage mass spectrometry (HCMS) and multidimensional chemical-biological analysis (MCBA) was proposed for the comprehensive exploration of Magnolia officinalis which is the main source of Magnolia bark. The strategy is divided into three main steps. In the first step, the stem bark, stem xylem, root bark, root xylem, leaf and rootlet of Magnolia officinalis were comprehensively analyzed using high-coverage mass spectrometry. In the second step, multivariate statistical analysis was used to explore the heterogeneity of the six parts and detect differential chemical components. In the third step, a combination of experimental screening and molecular docking was used to explore α-glucosidase inhibitors from Magnolia officinalis. Multidimensional chemical-biological analysis (MCBA) of Magnolia officinalis was achieved by combining the last two steps. Finally, a total of 103 compounds were identified from the whole plant of Magnolia officinalis. Differential components of stem bark, stem xylem, leaf, root bark, root xylem and rootlet were systematically revealed. A pair of positional isomers, namely magnolol and honokiol, were found to be α-glucosidase inhibitors. The activity of their combination is superior to that of each single compound, indicating that magnolol and honokiol are in a synergistic relationship. This strategy contributes to comprehensive exploitation of functional plants and effective alleviation of resource shortage. This study also provides a research paradigm for other similar traditional Chinese medicinal plants.


Asunto(s)
Magnolia , Espectrometría de Masas , Magnolia/química , Espectrometría de Masas/métodos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Simulación del Acoplamiento Molecular , Plantas Medicinales/química , Inhibidores de Glicósido Hidrolasas/análisis , Inhibidores de Glicósido Hidrolasas/química
2.
J Agric Food Chem ; 72(31): 17328-17342, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39045647

RESUMEN

Zanthoxyli radix is a popular tea among the elderly, and it is believed to have a positive effect on Alzheimer's disease. In this study, a highly effective three-step strategy was proposed for comprehensive analysis of the active components and biological functions of Zanthoxylum nitidum (ZN), including high-resolution LC-Q-TOF mass spectrometry (HRMS), multivariate statistical analysis for heterogeneity (MSAH), and experimental and virtual screening for bioactivity analysis (EVBA). A total of 117 compounds were identified from the root, stem, and leaf of ZN through HRMS. Bioactivity assays showed that the order of acetylcholinesterase (AChE) inhibitory activity from strong to weak was root > stem > leaf. Nitidine, chelerythrine, and sanguinarine were found to be the main differential components of root, stem, and leaf by OPLS-DA. The IC50 values of the three compounds are 0.81 ± 0.02, 0.14 ± 0.01, and 0.48 ± 0.01 µM respectively, indicating that they are potent and high-quality AChE inhibitors. Molecular docking showed that pi-pi T-shaped interactions and pi-lone pairs played important roles in AChE inhibition. This study not only explains the biological function of Zanthoxyli radix in alleviating Alzheimer's disease to some extent, but also lays the foundation for the development of stem and leaf of ZN.


Asunto(s)
Acetilcolinesterasa , Inhibidores de la Colinesterasa , Espectrometría de Masas , Simulación del Acoplamiento Molecular , Hojas de la Planta , Zanthoxylum , Zanthoxylum/química , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Acetilcolinesterasa/química , Acetilcolinesterasa/metabolismo , Hojas de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Raíces de Plantas/química , Tallos de la Planta/química , Cromatografía Líquida de Alta Presión , Humanos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología
3.
Int J Gen Med ; 17: 2433-2443, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38826510

RESUMEN

Introduction: Chondrocyte degeneration and senescence are characteristics of osteoarthritis (OA) and other joint degenerative diseases, and ferroptosis has been observed to regulate the development of OA. However, the role of the N6-methyladenosine (m6A) modification in OA ferroptosis remains unclear. Methods: This study performed series of assays to investigate the function of the m6A reader IGF2BP1 in OA ferroptosis, including m6A quantitative analysis, Iron (Fe2+) release analysis, Malondialdehyde (MDA) measurement, lipid peroxidation (ROS) detection and Glutathione (GSH) measurement. The molecular interaction and mechanism analysis was performed by Luciferase reporter assay, mRNA stability analysis and RNA immunoprecipitation (RIP) assay. Results: These results indicate that IGF2BP1 is upregulated in IL-1ß-induced chondrocytes. Functionally, IGF2BP1 silencing represses ferroptosis, including iron (Fe2+) accumulation, malondialdehyde, and reactive oxygen species (ROS). Mechanistically, among the potential downstream targets, matrix metalloproteinase-3 (MMP3) was observed to harbor a significant m6A modified site in the 3'-UTR. IGF2BP1 combines with MMP3 through the binding of m6A sites, thereby enhancing MMP3 mRNA stability. Discussion: In conclusion, our findings revealed the functions and mechanisms of m6A regulator IGF2BP1 in OA chondrocyte's ferroptosis, providing a novel target for OA treatment.

4.
ACS Nano ; 18(19): 12547-12559, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38695563

RESUMEN

Enantioselective sensing and separation represent formidable challenges across a diverse range of scientific domains. The advent of hybrid chiral membranes offers a promising avenue to address these challenges, capitalizing on their unique characteristics, including their heterogeneous structure, porosity, and abundance of chiral surfaces. However, the prevailing fabrication methods typically involve the initial preparation of achiral porous membranes followed by subsequent modification with chiral molecules, limiting their synthesis flexibility and controllability. Moreover, existing chiral membranes struggle to achieve coupled-accelerated enantioseparation (CAE). Here, we report a replacement strategy to controllably produce mesoscale and chiral silica-carbon (MCSC) hybrid membranes that comprise chiral pores by interfacial superassembly on a macroporous alumina (AAO) membrane, in which both ion- and enantiomers can be effectively and selectively transported across the membrane. As a result, the heterostructured hybrid membrane (MCSC/AAO) exhibits enhanced selectivity for cations and enantiomers of amino acids, achieving CAE for amino acids with an isoelectric point (pI) exceeding 7. Interestingly, the MCSC/AAO system demonstrates enhanced pH-sensitive enantioseparation compared to chiral mesoporous silica/AAO (CMS/AAO) with significant improvements of 78.14, 65.37, and 14.29% in the separation efficiency, separation factor, and permeate flux, respectively. This work promises to advance the synthesis of two or more component-integrated chiral nanochannels with multifunctional properties and allows a better understanding of the origins of the homochiral hybrid membranes.

5.
Adv Mater ; 36(25): e2401055, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38569116

RESUMEN

Atomic metal catalysts have unique electronic, structural, and catalytic properties, which are widely used in the field of catalysis. However, designing new simple synthesis methods to fabricate atomic metal catalysts is a challenge in catalytic applications. Herein, a one-step precursor combustion strategy is presented that starts directly from precursors of metal salts, using a spontaneous combustion process convert platinum nitrate to atomic Pt sites. The atomic Pt sites with low valence are anchored in the formed interface between grains on vacancy-enriched CeO2 nanosheets. The obtained Pt/CeO2-2 catalyst exhibits much higher three-way catalytic activities at low temperatures than Pt/CeO2-C catalysts prepared using the traditional impregnation method. Density functional theory calculations show that the generated lower valent Pt atoms in the CeO2 interface promote catalytic activity through reducing the energy barrier, and lead to an overall improvement of three-way catalytic activities. This facile strategy provides new insights into the study of the properties and applications of atomic noble metal catalysts.

6.
Nano Lett ; 23(24): 11899-11906, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38071625

RESUMEN

Cu-based catalysts possess great potential in the electrocatalytic nitrate (NO3-) reduction reaction for ammonia (NH3) synthesis. However, the low atomic economy limits their further application. Here we report a Cu single-atom (SA) incorporated in nitrogen-doped carbon (Cu SA/NC) with high atomic economy, which exhibits superior NH3 Faradaic efficiency (FE) of 100% along with an impressive NH3 yield rate of 7480 µg h-1 mgcat.-1. As counterparts, Cus+n/NC, with mixed SA and nanoparticles (NPs), shows decreasing NH3 FE with decreasing SA content, but the production of N2 and N2O increases gradually, which reaches the maximum on pure Cu NPs. In situ characterizations and theoretical calculations reveal that a higher NH3 FE of Cu SA/NC is ascribed to a lower free energy of the rate-limiting step (HNO* → N*) and effective inhibition for the N-N coupled process. This work provides the intuitive activity trends of Cu-based catalysts, opening an avenue for subsequent catalysts design.

7.
Plants (Basel) ; 12(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38068656

RESUMEN

Ethylene plays an important role in plant development and stress resistance. The rate-limiting enzyme in ethylene biosynthesis is 1-aminocyclopropane-1-carboxylic acid synthase (ACS). C. quinoa (Chenopodium quinoa) is an important food crop known for its strong tolerance to abiotic stresses. However, knowledge regarding the ACS gene family in C. quinoa remains restricted. In this study, we successfully identified 12 ACS genes (CqACSs) from the C. quinoa genome. Through thorough analysis of their sequences and phylogenetic relationships, it was verified that 8 out of these 12 CqACS isozymes exhibited substantial resemblance to ACS isozymes possessing ACS activity. Furthermore, these eight isozymes could be categorized into three distinct groups. The four remaining CqACS genes grouped under category IV displayed notable similarities with AtACS10 and AtACS12, known as amido transferases lacking ACS activity. The CqACS proteins bore resemblance to the AtACS proteins and had the characteristic structural features typically observed in plant ACS enzymes. Twelve CqACS genes were distributed across 8 out of the 18 chromosomes of C. quinoa. The CqACS genes were expanded from segment duplication. Many cis-regulatory elements related with various abiotic stresses, phytohormones, and light were found. The expression patterns of ACS genes varied across different tissues of C. quinoa. Furthermore, the analysis of gene expression patterns under abiotic stress showed that CqACS genes can be responsive to various stresses, implying their potential functions in adapting to various abiotic stresses. The findings from this research serve as a foundation for delving deeper into the functional roles of CqACS genes.

8.
ACS Nano ; 17(24): 25614-25624, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38064206

RESUMEN

Electrocatalytic nitrate (NO3-) reduction represents one of the most promising approaches to mitigate NO3- pollution and yield NH3, but it is still challenged by the atomic economy and selectivity issues of substantial active sites. Here, we describe a comprehensive investigation on a series of single-atom catalysts (SACs) using nitrogen-doped carbon as substrate (metal/NC). The essence of activity is related to the extent of the electron transfer capacity (SAs → NO3-). Among these examined SACs, the Cu/NC presents good performance toward NH3 synthesis, i.e., a maximum NH3 Faradaic efficiency of 100% with a high NH3 yield rate of up to 32,300 µg h-1 mgcat.-1. X-ray absorption fine structure spectra and density functional theory calculations provide evidence that the electronic structure of Cu-N4 coordination prohibits the formation of N2, N2O, and H2 and facilitates the orbital hybridization between the 2p orbitals of NO3- and 3d orbitals of Cu single-atom sites. Our study is believed to provide fundamental guidance for the future design of highly efficient electrocatalysts in NO3- reduction to NH3.

9.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(9): 984-990, 2023 Sep.
Artículo en Chino | MEDLINE | ID: mdl-37803960

RESUMEN

OBJECTIVE: To investigate the development present situation of the department of critical care medicine in Inner Mongolia Autonomous Region (hereinafter referred to as Inner Mongolia), in order to promote the standardized and homogeneous development of critical care medicine in Inner Mongolia, and also provide a reference for discipline construction and resource allocation. METHODS: A survey study was conducted in comprehensive intensive care unit (ICU) of tertiary and secondary hospitals in Inner Mongolia by online questionnaire survey and telephone data verification. The questionnaire was based on the Guidelines for the Construction and Management of Intensive Care Units (Trial) (hereinafter referred to as the Guidelines) issued by the National Health Commission in 2009 and the development trend of the discipline. The questionnaire covered six aspects, including hospital basic information, ICU basic information, personnel allocation, medical quality management, technical skill and equipment configuration. The questionnaire was distributed in September 2022, and it was filled out by the discipline leaders or department heads of each hospital. RESULTS: As of October 24, 2022, a total of 101 questionnaires had been distributed, 85 questionnaires had been recovered, and the questionnaire recovery rate had reached 84.16%, of which 71 valid questionnaires had been collected in a total of 71 comprehensive ICU. (1) There were noticeable regional differences in the distribution of comprehensive ICU in Inner Mongolia, with a relatively weak distribution in the east and west, and the overall distribution was uneven. The development of critical care medicine in Inner Mongolia was still lacking. (2) Basic information of hospitals: the population and economy restricted the development of ICU. The average number of comprehensive ICU beds in the western region was only half of that in the central region (beds: 39.0 vs. 86.0), and the average number of ICU beds in the eastern region was in the middle (83.6 beds), which was relatively uneven. (3) Basic information of ICU: among the 71 comprehensive ICU surveyed, there were 44 tertiary hospitals and 27 secondary hospitals. The ratio of ICU beds to total beds in tertiary hospitals was significantly lower than that in secondary hospitals [(1.59±0.81)% vs. (2.11±1.07)%, P < 0.05], which were significantly lower than the requirements of the Guidelines of 2%-8%. The utilization rate of ICU in tertiary and secondary hospitals [(63.63±22.40)% and (44.65±20.66)%, P < 0.01] were both lower than the bed utilization rate required by the Guidelines (75% should be appropriate). (4) Staffing of ICU: there were 376 doctors and 1 117 nurses in tertiary hospitals, while secondary hospitals had 122 doctors and 331 nurses. There were significant differences in the composition ratio of the titles of doctors, the degree of doctors, and the titles of nurses between tertiary and secondary hospitals (all P < 0.05). Most of the doctors in tertiary hospitals had intermediate titles (attending physicians accounted for 41.49%), while most of the doctors in secondary hospitals had junior titles (resident physicians accounted for 43.44%). The education level of doctors in tertiary hospitals was generally higher than that in secondary hospitals (doctors: 2.13% vs. 0, masters: 37.24% vs. 8.20%). The proportion of nurses in tertiary hospitals was significantly lower than that in secondary hospitals (17.01% vs. 24.47%). The ratio of ICU doctors/ICU beds [(0.64±0.27)%, (0.59±0.34)%] and ICU nurses/ICU beds [(1.76±0.56)%, (1.51±0.48)%] in tertiary and secondary hospitals all failed to meet the requirements above 0.8 : 1 and 3 : 1 of the Guidelines. (5) Medical quality management of ICU: compared with secondary hospitals, the proportion of one-to-one drug-resistant bacteria care in tertiary hospitals (65.91% vs. 40.74%), multimodal analgesia and sedation (90.91% vs. 66.67%), and personal digital assistant (PDA) barcode scanning (43.18% vs. 14.81%) were significantly higher (all P < 0.05). (6) Technical skills of ICU: in terms of technical skills, the proportion of bronchoscopy, blood purification, jejunal nutrition tube placement and bedside ultrasound projects carried out in tertiary hospitals were higher than those in secondary hospitals (84.09% vs. 48.15%, 88.64% vs. 48.15%, 61.36% vs. 55.56%, 88.64% vs. 70.37%, all P < 0.05). Among them, the placement of jejunal nutrition tube, bedside ultrasound and extracorporeal membrane oxygenation were mainly completed independently in tertiary hospitals, while those in secondary hospitals tended to be completed in cooperation. (7) Equipment configuration of ICU: in terms of basic equipment, the ratio of the total number of ventilators/ICU beds in tertiary and secondary hospitals [0.77% (0.53%, 1.07%), 0.88% (0.63%, 1.38%)], and the ratio of injection pump/ICU beds [1.70% (1.00%, 2.56%), 1.25% (0.75%, 1.88%)] didn't meet the requirements of the Guidelines. The equipment ratio was insuffcient, which means that the basic needs of development had not been met yet. CONCLUSIONS: The development of comprehensive ICU in Inner Mongolia has tended to mature, but there is still a certain gap in the development scale, personnel ratio and instruments and equipment compared with the Guidelines. Moreover, the comprehensive ICU appears the characteristics of relatively weak eastern and western regions, and the overall distribution is uneven. Therefore, it is necessary to increase efforts to invest in the construction of the department of critical care medicine.


Asunto(s)
Cuidados Críticos , Unidades de Cuidados Intensivos , Humanos , Encuestas y Cuestionarios , Centros de Atención Terciaria , China
10.
Arch Orthop Trauma Surg ; 143(12): 7063-7071, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37668661

RESUMEN

BACKGROUND: The optimal internal fixation for non-displaced femoral neck fractures remains controversial. This study aimed to compare the clinical results of the percutaneous compression plate (PCCP) with parallel screws (PS) in treating femoral neck fractures in elderly patients. MATERIALS AND METHODS: A total of 218 patients who underwent internal fixation were randomized to receive either a percutaneous compression plate (PCCP group) or parallel screws (PS group) using a computerized random sequence generator which was used to assign the order of randomization. Patients were assessed by the operating time, intraoperative blood loss, hemoglobin level drop, postoperative hospital stay, the time to full weight-bearing, reduction quality, fracture healing time, Harris hip score, and postoperative complications. RESULTS: There was no significant difference between PCCP and PS groups regarding operative time, intraoperative blood loss, hemoglobin level drop, postoperative hospital stays, reduction quality, and Harris hip score (p > 0.05). The time to full weight-bearing and the fracture healing time in the PCCP group were shorter than those in the PS group (p < 0.05). The overall complication rates were slightly lower in the PCCP compared to the PS patients, but there was no significant difference (p > 0.05). However, the implant failure rate was significantly higher in the PS group compared to the PCCP group (p < 0.05). CONCLUSIONS: The present study suggests that the PCCP is superior to the parallel screws fixation in the treatment of non-displaced elderly femoral neck fractures in terms of earlier full weight-bearing, shorter fracture healing time, and lower implant failure rate. Therefore, it may be a better therapeutic strategy for non-displaced femoral neck fractures in elderly patients.


Asunto(s)
Pérdida de Sangre Quirúrgica , Fracturas del Cuello Femoral , Humanos , Anciano , Resultado del Tratamiento , Estudios Prospectivos , Tornillos Óseos , Fracturas del Cuello Femoral/cirugía , Fijación Interna de Fracturas/métodos , Hemoglobinas , Estudios Retrospectivos
11.
Cell Mol Biol (Noisy-le-grand) ; 69(8): 179-184, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37715399

RESUMEN

As a chronic inflammatory autoimmune disease, rheumatoid arthritis (RA) causes significant destruction to joints and cartilage. So far, from RA patients, the synovial cells and subsynovial tissues reflected the positive expression of IL-18, IL-1ß, Caspase-1 and NLRP3, with the synovial tissues of those patients also expressing the zinc finger protein A20 at a significantly lower level compared with osteoarthritis (OA) ones. Thus, the inhibition of the NLRP3/caspase-1 signaling pathway can effectively down-regulate the expression of IL-1ß, but when NLRP3 inflammasomes are activated, they can also shear GSDMD and induce pyroptosis. These suggest that the Gasdermin family of proteins, downstream of the NLRP3 inflammasome, could be involved in pyroptosis. Previous studies have shown that A20 contributes largely as an anti-inflammatory factor in many inflammatory diseases, but it remains unclear whether zinc finger protein A20, as an inhibitor of NLRP3 inflammasomes, can play a protective role against RA by inhibiting NLRP3 inflammasome-mediated pyroptosis. Therefore, this study aimed to verify the effects of zinc finger protein A20 on NLRP3/ Caspase-1-mediated pyroptosis in rheumatoid arthritis synovial fibroblasts (HFLS-RA) cells through cell experiments and clinical bidirectional verification, aim to understand the regulatory mechanism of A20 on RA. The results of clinical trials showed that NLRP3, Caspase-1, IL-1ß and IL-18 were positively scattered in RA synovial cells and subsynovial tissue. The expression level of the zinc finger protein A20 in RA synovial tissues was significantly lower than that in OA synovial tissue and was negative, while zinc finger protein A20 was strongly positive in OA synovial tissue. In addition, HFLS-RA cells with siRNA-interfering zinc finger protein A20 were constructed at the cellular level, with the results also confirming that zinc finger protein A20 can play a protective role against RA by inhibiting NLRP3 inflammasome-mediated pyroptosis. In conclusion, this study is of great significance for understanding the role of the NLRP3-caspase-1-IL-1ß/ pyroptosis signaling pathway in the occurrence and development of RA. It is expected that the results will provide a theoretical basis for the immune regulation of innate immunity in the occurrence and development of RA, while providing a new therapeutic target for the clinical treatment of RA.


Asunto(s)
Artritis Reumatoide , Osteoartritis , Humanos , Caspasa 1 , Piroptosis , Inflamasomas , Interleucina-18 , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa , Transducción de Señal
12.
ACS Appl Mater Interfaces ; 15(20): 25058-25065, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37162360

RESUMEN

Gallium nitride (GaN) has been considered one of the most promising materials for the next-generation power and radio-frequency electronic devices, as they can operate at higher voltage, higher frequency, and higher temperature, compared with their silicon (Si) counterparts. However, the fresh GaN surface is susceptible to the natural oxidation composed of Ga2O3, Ga2O, and other intermediate oxidation states. Moreover, the oxidized GaN surface no longer features the distinct atomic step-terrace morphology, resulting in a degraded interface when gate or passivation dielectrics are deposited without appropriate pretreatment. It is responsible for the degraded performance of GaN-based devices such as current collapse and threshold voltage instability. In this study, the proposed high-temperature (500 °C) remote plasma pretreatments (RPPs) can play a significant role in addressing the issue of the deteriorated GaN surface exposed to air. Atomic step-terrace morphology was recovered after 500 °C-RPP due to the removal of oxides and suboxides. First-principles calculations verified that Ga2O at the GaN surface leads to interface states at ∼2.9 eV (EC-E ∼ 0.4 eV) in the bandgap, which is consistent with the increase of interface states at the EC-E range of 0.4-0.9 eV measured through constant-capacitance deep-level transient spectroscopy. Meanwhile, deep interface states and surface-related current collapse are well suppressed in GaN metal-insulator-semiconductor devices. These improved properties by 500 °C-RPP are generalizable to a broader range, including pre-gate and pre-passivation treatment, of which a decent surface/interface is desirable for high-performance GaN-based devices.

13.
Environ Sci Technol ; 57(8): 3134-3144, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36785514

RESUMEN

Electrocatalytic ammonia (NH3) synthesis from the reduction of nitrate (NO3-) is one of the effective and mild methods to treat nitrogen-containing wastewater from stationary sources and to obtain NH3 readily compared with the Haber-Bosch process. However, the low efficiency of electrocatalytic NO3- reduction to NH3 on traditional Cu-based catalysts hinders their practical application. Here, we prepare a Au/Cu single atom (SA) alloy (Au/Cu SAA) that shows a high performance of NH3 synthesis with 99.69% Faradaic efficiency at -0.80 V vs RHE. The structures of Au SAs and alloyed Au/Cu are confirmed by the detailed characterizations. Online differential electrochemical mass spectrometry confirms the occurrence of key reaction intermediates (*NO2, *NO, and *NH3). Density functional theory calculations demonstrate that Au SAs efficiently reduce the adsorption energy of *NO3-, and the newly formed Au-Cu bonds boost the reduction process of *NO2 to *NO. Meanwhile, Au/Cu SAAs produce significantly less N2 and N2O byproducts due to the prohibition of N-N coupling on single atoms, which finally leads to excellent Faradaic efficiency and NH3 selectivity.


Asunto(s)
Amoníaco , Nitratos , Dióxido de Nitrógeno , Adsorción , Aleaciones
14.
Small ; 19(20): e2207695, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36793161

RESUMEN

As a traditional method of ammonia (NH3 ) synthesis, Haber-Bosch method expends a vast amount of energy. An alternative route for NH3 synthesis is proposed from nitrate (NO3 - ) via electrocatalysis. However, the structure-activity relationship remains challenging and requires in-depth research both experimentally and theoretically. Here an N-coordinated Cu-Ni dual-single-atom catalyst anchored in N-doped carbon (Cu/Ni-NC) is reported, which has competitive activity with a maximal NH3 Faradaic efficiency of 97.28%. Detailed characterizations demonstrate that the high activity of Cu/Ni-NC mainly comes from the contribution of Cu-Ni dual active sites. That is, (1) the electron transfer (Ni â†’ Cu) reveals the strong electron interaction of Cu-Ni dual-single-atom; (2) the strong hybridizations of Cu 3d-and Ni 3d-O 2p orbitals of NO3 - can accelerate electron transfer from Cu-Ni dual-site to NO3 - ; (3) Cu/Ni-NC can effectively decrease the rate-limiting step barriers, suppress N-N coupling for N2 O and N2 formation and hydrogen production.

15.
Genes (Basel) ; 15(1)2023 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-38254931

RESUMEN

Plant protein phosphatase 2Cs (PP2Cs) function as inhibitors in protein kinase cascades involved in various processes and are crucial participants in both plant development and signaling pathways activated by abiotic stress. In this study, a genome-wide study was conducted on the CqPP2C gene family. A total of putative 117 CqPP2C genes were identified. Comprehensive analyses of physicochemical properties, chromosome localization and subcellular localization were conducted. According to phylogenetic analysis, CqPP2Cs were divided into 13 subfamilies. CqPP2Cs in the same subfamily had similar gene structures, and conserved motifs and all the CqPP2C proteins had the type 2C phosphatase domains. The expansion of CqPP2Cs through gene duplication was primarily driven by segmental duplication, and all duplicated CqPP2Cs underwent evolutionary changes guided by purifying selection. The expression of CqPP2Cs in various tissues under different abiotic stresses was analyzed using RNA-seq data. The findings indicated that CqPP2C genes played a role in regulating both the developmental processes and stress responses of quinoa. Real-time quantitative reverse transcription PCR (qRT-PCR) analysis of six CqPP2C genes in subfamily A revealed that they were up-regulated or down-regulated under salt and drought treatments. Furthermore, the results of yeast two-hybrid assays revealed that subfamily A CqPP2Cs interacted not only with subclass III CqSnRK2s but also with subclass II CqSnRK2s. Subfamily A CqPP2Cs could interact with CqSnRK2s in different combinations and intensities in a variety of biological processes and biological threats. Overall, our results will be useful for understanding the functions of CqPP2C in regulating ABA signals and responding to abiotic stress.


Asunto(s)
Chenopodium quinoa , Humanos , Chenopodium quinoa/genética , Estudio de Asociación del Genoma Completo , Filogenia , Evolución Biológica , Interpretación Estadística de Datos , Monoéster Fosfórico Hidrolasas
16.
Physiol Mol Biol Plants ; 28(7): 1421-1435, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36051231

RESUMEN

Three species of Gentiana (Gentiana manshurica kitag., Gentiana scabra bunge., and Gentiana triflora pall.) were the main source for an important traditional Chinese medicine, "Longdan", which was first mentioned in " Shennong materia medica Sutra " 2000 years ago. Until recently, there were very few reports on taxonomic classification of these three traditional medicinal Gentiana species. In the current study, chloroplast genomes of the three Gentiana species were sequenced and the phylogenetic analyses were performed in combination with 31 NCBI downloaded Gentiana species sequences and two species of Swertia as outgroup. Based on the phylogenetic results, a new taxonomic classification for Gentiana was proposed, including 4 independent clades with 6 subdivisions (Group 1-Group 6). All the general features, SSR characteristics and gene composition of Gentiana chloroplast genomes strongly supported such a new classification system for Gentiana, which could lay a theoretical foundation for Gentiana in the molecular evolutionary research. Finally, phylogenetic analyisis also demonstrated that the three examined species from Gentiana could cluster together into one group (Group 6), which was far away from the evolutionary position of the medicinal species, Gentiana rigescens Franch, which was consistent with the traditional classification in traditional medicinal uses and taxonomy. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01217-0.

17.
J Sep Sci ; 45(14): 2446-2457, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35503988

RESUMEN

An herbal prescription is usually composed of several herbal medicines. The complex and diverse components bring great challenges to its bioactivity study. To comprehensively analyze the bioactivity of an herbal prescription, a new strategy based on peak-by-peak cutting and knock-out chromatography was proposed. In this strategy, active compounds were screened out via peak-by-peak cutting from an herbal extract, and the influence of a compound on the overall activity of the herbal extract was evaluated by knock-out chromatography. Qiliqiangxin capsule is an herbal prescription composed of 11 herbal medicines for the treatment of chronic heart failure. A total of 71 peaks were collected through peak-by-peak cutting, and each peak was identified by a high-resolution mass spectrum. The bioassay against 1,1-diphenyl-2-picrylhydrazyl showed that two types of compounds namely salvianolic acids and caffeoylquinic acids were potent scavengers. Knock-out chromatography suggested that the removal of one single compound had no obvious influence on the overall activity of the Qiliqiangxin capsule. After all the main peaks in the Qiliqiangxin capsule were knocked out, the remaining part still exhibited a potent activity, indicating high activity stability of the Qiliqiangxin capsule. The proposed strategy is helpful for the comprehensive analysis of the bioactivity of other herbal prescriptions.


Asunto(s)
Medicamentos Herbarios Chinos , Plantas Medicinales , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/análisis , Plantas Medicinales/química , Prescripciones
18.
J Healthc Eng ; 2022: 4287555, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35310174

RESUMEN

Background: The clinical influence of the preoperative and postoperative therapies for recovery after the joint replacement surgery is still questionable. This study of systematic review and meta-analysis focuses on analyzing the clinical effects of preoperative rehabilitation among the patients who are planning to opt for joint replacement surgery for enhanced results. Objective: Randomized clinical trials were selected where preoperative therapeutic exercises were performed by adults for preoperative rehabilitation in patients who were planning for replacement surgery for better outcomes and identified through databases and screening. Two reviewers were responsible for extracting appropriate studies, relevant data, assessing the risks, therapeutic validity, etc. Material and Methods. We performed random-effects meta-analysis for calculation of risk ratios and odds ratios, for knee and hip surgery cases. Analysis of length of hospital stay, short-term-based recovery period during hospital stay, total hip replacement functional recovery during hospital stay, short-term recovery of self-reported functioning, etc. was performed. Results: Functional scores, postoperative pain, recovery time, length of hospital stay, and quality of life were studied. Of the seven studies included, the data of 614 patients were studied. The total number of participants in both exercise and control groups was analyzed to assess the bias of the study where the risk ratio was 0.96 and (0.74-1.25) was the 95% CI. Short-term-based recovery period during hospital stay for knee replacement was analyzed where 0.87 was the risk ratio and (0.61-1.23) was the 95% CI and for hip replacement where 0.99 was the risk ratio and (0.68-1.44) was the 95% CI. The RR for total hip replacement functional recovery during hospital stay was 0.80 with 95% CI (0.54-1.19). The RR for short-term recovery of self-reported functioning was 0.98 with 95% CI (0.76-1.26). Outcome analysis for pain and functionality evaluation was performed and assessed using WOMAC, HOOS, and HHS scores where the standardized mean difference was 0.38 and (0.20-0.57) was the 95% CI in hip surgery pain analysis and in knee surgery, 0.00 was the standardized mean difference and (-0.18-0.19) was the 95% CI. Conclusion: Long-term outcomes were not affected by the preoperative rehabilitation. Though there was a slight improvement in early postoperative pain, this is not much of clinical significance.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Adulto , Artroplastia de Reemplazo de Rodilla/rehabilitación , Humanos , Dolor Postoperatorio/prevención & control , Ejercicio Preoperatorio , Calidad de Vida
19.
Angew Chem Int Ed Engl ; 61(23): e202202556, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35297151

RESUMEN

The electrochemical nitrate reduction reaction (NITRR) provides a promising solution for restoring the imbalance in the global nitrogen cycle while enabling a sustainable and decentralized route to source ammonia. Here, we demonstrate a novel electrocatalyst for NITRR consisting of Rh clusters and single-atoms dispersed onto Cu nanowires (NWs), which delivers a partial current density of 162 mA cm-2 for NH3 production and a Faradaic efficiency (FE) of 93 % at -0.2 V vs. RHE. The highest ammonia yield rate reached a record value of 1.27 mmol h-1 cm-2 . Detailed investigations by electron paramagnetic resonance, in situ infrared spectroscopy, differential electrochemical mass spectrometry and density functional theory modeling suggest that the high activity originates from the synergistic catalytic cooperation between Rh and Cu sites, whereby adsorbed hydrogen on Rh site transfers to vicinal *NO intermediate species adsorbed on Cu promoting the hydrogenation and ammonia formation.

20.
Environ Sci Technol ; 56(6): 3604-3612, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35230808

RESUMEN

Photocatalysis presents a feasible option to control low-concentration NO emissions from industrial burning facilities, and increasing excitons in quantity and improving surface activity are the crucial issues to be solved. Plasmonic silver with the orientation of the (111) plane is uniformly distributed on the Ti-O termination of the SrTiO3 (STO) (100) plane (major). The NO conversion rate has a sixfold increment compared to pristine STO. Meanwhile, the toxic NO2 had a significant decline in the absence of water. This high performance could be attributed to the unique property of the localized surface plasmonic resonance of silver particles, which increases the optical response range of the catalyst. Meanwhile, the formation of a Schottky junction could promote the charge separation and enhance the lifetime of excitons via the electron transfer from silver particles to STO. More importantly, the Ag-O bond of the heterojunction increases the charge density of adjacent Ti, preferring to bond with the antibonding orbital electron of adsorbed molecules, which offers a favorable channel for the NO adsorption and activation of reactive oxidation species.

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