RESUMO
Heterogeneous electrocatalysis lies at the center of various technologies that could help enable a sustainable future. However, its complexity makes it challenging to accurately and efficiently model at an atomic level. Here, we review emerging atomistic methods to simulate the electrocatalytic interface with special attention devoted to the components/effects that have been challenging to model, such as solvation, electrolyte ions, electrode potential, reaction kinetics, and pH. Additionally, we review relevant computational spectroscopy methods. Then, we showcase several examples of applying these methods to understand and design catalysts relevant to green hydrogen. We also offer experimental views on how to bridge the gap between theory and experiments. Finally, we provide some perspectives on opportunities to advance the field.
RESUMO
A key challenge in pathway design is finding proper enzymes that can be engineered to catalyze a non-natural reaction. Although existing tools can identify potential enzymes based on similar reactions, these tools encounter several issues. Firstly, the calculated similar reactions may not even have the same reaction type. Secondly, the associated enzymes are often numerous and identifying the most promising candidate enzymes is difficult due to the lack of data for evaluation. Thirdly, existing web tools do not provide interactive functions that enable users to fine-tune results based on their expertise. Here, we present REME (https://reme.biodesign.ac.cn/), the first integrated web platform for reaction enzyme mining and evaluation. Combining atom-to-atom mapping, atom type change identification, and reaction similarity calculation enables quick ranking and visualization of reactions similar to an objective non-natural reaction. Additional functionality enables users to filter similar reactions by their specified functional groups and candidate enzymes can be further filtered (e.g. by organisms) or expanded by Enzyme Commission number (EC) or sequence homology. Afterward, enzyme attributes (such as kcat, Km, optimal temperature and pH) can be assessed with deep learning-based methods, facilitating the swift identification of potential enzymes that can catalyze the non-natural reaction.
Assuntos
Enzimas , Software , Enzimas/química , Enzimas/metabolismo , Mineração de Dados/métodos , Internet , Aprendizado Profundo , BiocatáliseRESUMO
Alumina materials, as one of the cornerstones of the modern chemical industry, possess physical and chemical properties that include excellent mechanical strength and structure stability, which also make them highly suitable as catalyst supports. Alumina-supported Pd-based catalysts with the advantages of exceptional catalytic performance, flexible regulated surface metal/acid sites, and good regeneration ability have been widely used in many traditional chemical industry fields and have also shown great application prospects in emerging fields. This review aims to provide an overview of the recent advances in alumina and its supported Pd-based catalysts. Specifically, the synthesis strategies, morphology transformation mechanisms, and structural properties of alumina with various morphologies are comprehensively summarized and discussed in-depth. Then, the preparation approaches of Pd/Al2O3 catalysts (impregnation, precipitation, and other emerging methods), as well as the metal-support interactions (MSIs), are revisited. Moreover, Some promising applications have been chosen as representative reactions in fine chemicals, environmental purification, and sustainable development fields to highlight the universal functionality of the alumina-supported Pd-based catalysts. The role of the Pd species, alumina support, promoters, and metal-support interactions in the enhancement of catalytic performance are also discussed. Finally, some challenges and upcoming opportunities in the academic and industrial application of the alumina and its supported Pd-based are presented and put forward.
RESUMO
Immune checkpoint inhibitors (ICIs) have shown promising efficacy in multiple cancers including biliary tract cancers (BTCs). However, the data focusing on the efficacy of ICIs in patients with gallbladder cancer (GBC) is still limited. In this study, we aim to assess the efficacy of ICIs in GBC and explore the clinicopathologic and molecular markers associated with ICI benefit. We retrospective analyzed 69 GBC patients who had received ICI therapy between January 2016 and December 2020. Tumor samples were obtained for genomic sequencing and immunohistochemical analysis. The median progression-free survival (PFS) and overall survival (OS) was 4.4 months and 8.5 months, respectively. Multivariate analysis indicated that alcohol intake history, carcinoma embryonic antigen (CEA) level ≥100 U/mL, and cutaneous immune-related adverse events (irAEs) were independent prognostic factors for PFS. CEA level ≥100 U/mL and cutaneous irAEs were independent prognostic factors for OS. The objective response rate and disease control rate (DCR) were 15.9% and 37.7%, respectively. Patients with cutaneous irAEs, high CD8+ T cell infiltrated or immune inflamed GBCs had higher DCR. Patients with high CD8+ T cell infiltrated or immune inflamed GBCs also had a notably improved prognosis. These results suggest that ICIs were effective in patients with GBC. High CEA level, cutaneous irAEs, high CD8+ T cell infiltration, and immune inflamed phenotype could be useful for predicting the efficacy of ICIs in GBC.
Assuntos
Neoplasias da Vesícula Biliar , Inibidores de Checkpoint Imunológico , Humanos , Neoplasias da Vesícula Biliar/tratamento farmacológico , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Prognóstico , Adulto , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Intervalo Livre de Progressão , Biomarcadores Tumorais , Resultado do TratamentoRESUMO
Astragalus mongholicus is a medicinal plant that is known to decrease in quality in response to continuous cropping. However, the differences in the root-associated microbiome and root exudates in the rhizosphere soil that may lead to these decreases are barely under studies. We investigated the plant biomass production, root-associated microbiota, and root exudates of A. mongholicus grown in two different fields: virgin soil (Field I) and in a long-term continuous cropping field (Field II). Virgin soil is soil that has never been cultivated for A. mongholicus. Plant physiological measurements showed reduced fresh and dry weight of A. mongholicus under continuous cropping conditions (i.e. Field II). High-throughput sequencing of the fungal and bacterial communities revealed differences in fungal diversity between samples from the two fields, including enrichment of potentially pathogenic fungi in the roots of A. mongholicus grown in Field II. Metabolomic analysis yielded 20 compounds in A. mongholicus root exudates that differed in relative abundance between rhizosphere samples from the two fields. Four of these metabolites (2-aminophenol, quinic acid, tartaric acid, and maleamate) inhibited the growth of A. mongholicus, the soil-borne pathogen Fusarium oxysporum, or both. This comprehensive analysis enhances our understanding of the A. mongholicus microbiome, root exudates, and interactions between the two in response to continuous cropping. These results offer new information for future design of effective, economical approaches to achieving food security.
Assuntos
Microbiota , Raízes de Plantas , Rizosfera , Microbiologia do Solo , Raízes de Plantas/microbiologia , Astrágalo/microbiologia , Exsudatos de Plantas/metabolismo , Fungos/genética , Fungos/fisiologia , Produção Agrícola/métodos , Bactérias/genética , Bactérias/metabolismoRESUMO
Co-free Li-rich Mn-based cathode materials are garnering great interest because of high capacity and low cost. However, their practical application is seriously hampered by the irreversible oxygen escape and the poor cycling stability. Herein, a reversible lattice adjustment strategy is proposed by integrating O vacancies and B doping. B incorporation increases TMâO (TM: transition metal) bonding orbitals whereas decreases the antibonding orbitals. Moreover, B doping and O vacancies synergistically increase the crystal orbital bond index values enhancing the overall covalent bonding strength, which makes TMâO octahedron more resistant to damage and enables the lattice to better accommodate the deformation and reaction without irreversible fracture. Furthermore, Mott-Hubbard splitting energy is decreased due to O vacancies, facilitating electron leaps, and enhancing the lattice reactivity and capacity. Such a reversible lattice, more amenable to deformation and forestalling fracturing, markedly improves the reversibility of lattice reactions and mitigates TM migration and the irreversible oxygen redox which enables the high cycling stability and high rate capability. The modified cathode demonstrates a specific capacity of 200 mAh g-1 at 1C, amazingly sustaining the capacity for 200 cycles without capacity degradation. This finding presents a promising avenue for solving the long-term cycling issue of Li-rich cathode.
RESUMO
Selective electrodialysis (ED) is a promising membrane-based process to separate Li+ from Mg2+, which is the most critical step for Li extraction from brine lakes. This study theoretically compares the ED-based Li/Mg separation performance of different monovalent selective cation exchange membranes (CEMs) and nanofiltration (NF) membranes at the coupon scale using a unified mass transport model, i.e., a solution-friction model. We demonstrated that monovalent selective CEMs with a dense surface thin film like a polyamide film are more effective in enhancing the Li/Mg separation performance than those with a loose but highly charged thin film. Polyamide film-coated CEMs when used in ED have a performance similar to that of polyamide-based NF membranes when used in NF. NF membranes, when expected to replace monovalent selective CEMs in ED for Li/Mg separation, will require a thin support layer with low tortuosity and high porosity to reduce the internal concentration polarization. The coupon-scale performance analysis and comparison provide new insights into the design of composite membranes used for ED-based selective ion-ion separation.
RESUMO
Traditional half-Heusler thermoelectric materials, identified as 18-electron compounds, are characterized by the high power factor and the high lattice thermal conductivity. Interestingly, the emerging 19-electron half-Heusler compounds were also found to be promising thermoelectric materials, but with a 5-10 times lower lattice thermal conductivity. Since the two kinds of compounds have similar chemical and physical structures, such as TiCoSb and VCoSb, the large difference in lattice thermal conductivity is a puzzling question. Here, we present a theoretical study to clarify the lattice thermal transport in half-Heusler thermoelectric materials. Based on electronic band structure analysis, we show that the two transition-metal elements in half-Heusler compounds form the strong and direct d-d interaction that is responsible for the high lattice thermal conductivity of 18-electron compounds. In 19-electron half-Heusler compounds, however, the extra valence electron enters the d-d antibonding states, which significantly weakens the atomic bond strength, leading to a large decrease in the cohesive energy. The resulting softened acoustic phonons enhance the phonon-phonon scattering, and thus reduce the lattice thermal conductivity significantly. By constructing an artificial 18-e compound V0.5Sc0.5CoSb, it is proved that the one less electron relative to VCoSb increases the lattice thermal conductivity significantly.
RESUMO
The incidence of idiopathic pulmonary fibrosis (IPF) has been steadily increasing each year, posing significant challenges in its treatment. In this study, we conducted the design and synthesis of 23 new inhibitors that specifically target the TGF-ß1/Smad3 pathway. Initially, we employed a cell model of TGF-ß-induced pulmonary fibrosis, using cell survival rate and HYP expression as indicators to identify the potent ingredient 5aa, which demonstrated significant anti-pulmonary fibrosis activity. Subsequently, we induced mice with bleomycin (BLM) to establish an experimental animal model of pulmonary fibrosis, and evaluated the pharmacodynamics of 5aa in vivo against pulmonary fibrosis. The alterations in HYP and collagen levels in BLM-induced pulmonary fibrosis mice were analyzed using ELISA and immunohistochemistry techniques. The results indicated that compound 5aa effectively suppressed the fibrotic response induced by TGF-ß1, inhibited the expression of the fibrotic marker α-SMA, and hindered the EMT process in NIH3T3 cells. Additionally, oral administration of 5aa demonstrated significant therapeutic effects in a mouse model of IPF, comparable to the established drug Nintedanib. Moreover, compound 5aa exhibited higher bioavailability in vivo compared to Nintedanib. These collective outcomes suggest that 5aa holds promise as a potential inhibitor of TGF-ß1/Smad3 signaling for the treatment of IPF.
Assuntos
Fibrose Pulmonar Idiopática , Transdução de Sinais , Proteína Smad3 , Fator de Crescimento Transformador beta1 , Animais , Proteína Smad3/metabolismo , Proteína Smad3/antagonistas & inibidores , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Camundongos , Transdução de Sinais/efeitos dos fármacos , Estrutura Molecular , Humanos , Bleomicina , Relação Estrutura-Atividade , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Relação Dose-Resposta a Droga , MasculinoRESUMO
An unprecedented spiro-C-glycoside adduct, heteryunine A (1), along with two uncommon alkaloids featuring a 2,3-diketopiperazine skeleton, heterpyrazines A (2) and B (3), were discovered in the roots of Heterosmilax yunnanensis. The detailed spectroscopic analysis helped to clarify the planar structures of these compounds. Compound 1, containing 7 chiral centers, features a catechin fused with a spiroketal and connects with a tryptophan derivative by a CC bond. Its complex absolute configuration was elucidated by rotating frame overhauser enhancement spectroscopy (ROESY), specific rotation, and the 13C nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) calculation. The possible biosynthetic routes for 1 were deduced. Compounds 1 and 2 showed significant antifibrotic effects and further research revealed that they inhibited the activation, migration and proliferation of hepatic stellate cells (HSCs) through suppressing the activity of Ras homolog family member A (RhoA).
RESUMO
OBJECTIVES: The pathology of Tardive Dyskinesia (TD) has yet to be fully understood, but there have been proposed hypotheses for the cause of this condition. Our team previously reported a possible association of TD with the Complement Component C4 gene in the HLA region. In this study, we explored the HLA region further by examining two previously identified schizophrenia-associated HLA-region single-nucleotide polymorphisms (SNPs), namely rs13194504 and rs210133. METHODS: The SNPs rs13194504 and rs210133 were tested for association with the occurrence and severity of TD in a sample of 172 schizophrenia patients who were recruited for four studies from three different clinical sites in Canada and USA. RESULTS: The rs13194504 AA genotype was associated with decreased severity for TD as measured by Abnormal Involuntary Movement Scale (AIMS) scores (p = 0.047) but not for TD occurrence. SNP rs210133 was not significantly associated with either TD occurrence or AIMS scores. CONCLUSION: Our findings suggest that the rs13194504 AA genotype may play a role in TD severity, while SNP rs210133 may not have a major role in the risk or severity of TD.
Assuntos
Polimorfismo de Nucleotídeo Único , Esquizofrenia , Discinesia Tardia , Humanos , Esquizofrenia/genética , Discinesia Tardia/genética , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Fatores de Risco , Marcadores Genéticos , Índice de Gravidade de Doença , Genótipo , Predisposição Genética para Doença , Canadá , Antipsicóticos/efeitos adversosRESUMO
OBJECTIVES: To examine (1) how visual green space quantity and quality affect depression among older adults; (2) whether and how the links may be mediated by perceived stress, physical activity, neighbourhood social cohesion, and air pollution (PM2.5); and (3) whether there are differences in the mediation across visual green space quantity and quality. METHOD: We used older adults samples (aged over 65) from the WHO Study on Global Ageing and Adult Health in Shanghai, China. Depression was quantified by two self-reported questions related to the diagnosis of depression and medications or other treatments for depression. Visual green space quantity and quality were calculated using street view images and machine learning methods (street view green space = SVG). Mediators included perceived stress, social cohesion, physical activity, and PM2.5. Multilevel logistic and linear regression models were applied to understand the mediating roles of the above mediators in the link between visual green space quantity and quality and depression in older adults. RESULTS: SVG quantity and quality were negatively related to depression. Significant partial mediators for SVG quality were social cohesion and perceived stress. For SVG quantity, there was no evidence that any of the above mediators mediated the association. CONCLUSION: Our results indicated that visual green space quantity and quality may be related to depression in older adults through different mechanisms.
RESUMO
This paper investigates the impact of mobility on underwater acoustic communication networks in which the propagation delay is comparable to or larger than the packet duration. An underwater acoustic wireless network, consisting of static and mobile nodes, is studied for its link-layer channel utilization. Synchronous and asynchronous media access control (MAC) protocols are employed with ALOHA, TDMA (time-division multiple access), and artificial intelligence (AI) agent nodes. The simulation results of a multi-node network show that the asynchronous MAC protocols achieve up to 6.66× higher channel utilization than synchronous protocols by allowing time slots to be shorter than the maximum propagation delay among nodes and permitting asynchronous transmission time. The high mobility of a few mobile nodes also favors asynchronous protocols and increases the overall channel utilization. However, node mobility causes more difficulties for the AI node to learn the environment, which may be ineffective to achieve higher gains in channel utilization.
RESUMO
Raspberry (Rubus corchorifolius) plants hold historical, economic, and medicinal importance in China (Yang et al. 2022). Raspberries are cultivated to generate income for local farmers in Lintao County, Dingxi City, Gansu Province. However, farmers encountered challenges due to raspberry plants exhibiting root rot disease, resulting in plant death. During a thorough field survey conducted in June 2022, symptoms ranging from leaf yellowing and wilting to necrotic lesions and root rots were observed, where approximately 30% of raspberry plants were affected. Five diseased and healthy plants were collected from the farmers' fields in Lintao (35.53oN, 103.84oE) for pathogen identification. Symptomatic and asymptomatic root tissues were surface sterilized with 75% ethanol for 30 s and 3% NaOCl for 5 min, followed by three rinses in sterile water. Small pieces (0.5 × 0.5 cm) were cut and incubated on potato dextrose agar (PDA) plates at 25°C for 7-10 days. Twenty-two pure Fusarium isolates, which displayed four distinct colony groups morphologically, were obtained. Pathogenicity tests on isolates RB10, RB1, RB30, and RB23, representing each colony group, revealed that RB10 exhibited symptoms similar to those observed in the field. The RB10 strain produced yellowish-white to greyish-white colonies on PDA and was then cultured in a carboxymethylcellulose (CMC) broth for enhanced conidia production (Zhang et al. 2020). Macroconidia were sickle-shaped or slightly curved, with three to five septa (19.2 to 38.5 x 3.1 to 5.8 µm, n =40). Microconidia were oval to ellipsoidal, non-septate or featuring 1 to 2 septa (4.8 to 10.5 x 2.1 to 5.2 µm, n=20). These morphological features indicated the isolate was similar to Fusarium avenaceum (Leslie and Summerell, 2006). For further identification of the strains, genomic regions (ITS-rDNA, TEF-1α, and RPB2) were amplified and sequenced using specific primers ITS1/ITS4, EF-1/EF-2, and 5f2/7cr, respectively (O'Donnell et al. 2010; Uwaremwe et al. 2021; Zarrin et al. 2016). PCR BLASTn queries of NCBI GenBank revealed a 99.8% (522 bp), 99.4% (355 bp) and 99.6% (985 bp) homology with F. avenaceum (MZ724839.1, MN271631.1, and MK185026.1), respectively. Sequences were deposited in GenBank (ITS, OR735571; TEF-1α, PP216660; RPB2, PP857820). One-year-old raspberry seedlings were planted in pots with a sterile soil mix (2:2:1 v/v ratio of soil, peat, and vermiculite) under controlled greenhouse conditions (23-26°C, 16h light/8h dark). A month post-planting, taproots were wounded in six pots and inoculated with 20 ml of conidia suspension (106 conidia/ml), while the other six pots were maintained as controls. After 14 days, RB10-infected plants showed symptoms similar to field observations, while controls remained healthy. The experiment was conducted twice, and re-isolation confirmed both the pathogenicity and identity of the pathogen. In the concatenated phylogenetic tree of ITS, TEF-1α and RPB2, strain RB10 was clustered with the F. avenaceum representative strains KG502, KG431 and F094. Studies revealed F. avenaceum varied pathogenicity across plants (Bugingo, 2022; Moparthi et al. 2020& 2024; Yli-Mattila et al. 2018), and it has been reported to induce raspberry fruit rot (Wang et al. 2017). However, no previous reports linked this fungus to raspberry root rot. This report is crucial for understanding the impact of root rot disease on raspberry cultivation and developing effective management strategies.
RESUMO
The present study aimed to investigate the effect and mechanism of Bupleuri Radix-Paeoniae Radix Alba medicated plasma on HepG2 hepatoma cells by regulating the microRNA-1297(miR-1297)/phosphatase and tensin homologue deleted on chromosome 10(PTEN) signaling axis. Real-time quantitative PCR(RT-qPCR) was carried out to determine the mRNA levels of miR-1297 and PTEN in different hepatoma cell lines. The dual luciferase reporter assay was employed to verify the targeted interaction between miR-1297 and PTEN. The cell counting kit-8(CCK-8) was used to detect cell proliferation, and the optimal concentration and intervention time of the medicated plasma were determined. The cell invasion and migration were examined by Transwell assay and wound healing assay. Cell cycle distribution was detected by PI staining, and the apoptosis of cells was detected by Annexin V-FITC/PI double staining. The mRNA levels of miR-1297, PTEN, protein kinase B(Akt), and phosphatidylinositol 3-kinase(PI3K) were determined by RT-qPCR. Western blot was employed to determine the protein levels of PTEN, Akt, p-Akt, caspase-3, caspase-9, B-cell lymphoma-2(Bcl-2), and Bcl-2-associated X protein(Bax). The results showed that HepG2 cells were the best cell line for subsequent experiments. The dual luciferase reporter assay confirmed that miR-1297 could bind to the 3'-untranslated region(3'UTR) in the mRNA of PTEN. The medicated plasma inhibited the proliferation of HepG2 cells, and the optimal intervention concentration and time were 20% and 72 h. Compared with the blank plasma, the Bupleuri Radix-Paeoniae Radix Alba medicated plasma, miR-1297 inhibitor, miR-1297 inhibitor + medicated plasma all inhibited the proliferation, invasion, and migration of HepG2 cells, increased the proportion of cells in the G_0/G_1 phase, decreased the proportion of cells in the S phase, and increased the apoptosis rate. The medicated plasma down-regulated the mRNA levels of miR-1297, PI3K, and Akt and up-regulated the mRNA level of PTEN. In addition, it up-regulated the protein levels of PTEN, Bax, caspase-3, and caspsae-9 and down-regulated the protein levels of p-Akt, p-PI3K, and Bcl-2. In conclusion, Bupleuri Radix-Paeoniae Radix Alba medicated plasma can inhibit the expression of miR-1297 in HepG2 hepatoma cells, promote the expression of PTEN, and negatively regulate PI3K/Akt signaling pathway, thereby inhibiting the proliferation and inducing the apoptosis of HepG2 cells.
Assuntos
Carcinoma Hepatocelular , Medicamentos de Ervas Chinesas , Neoplasias Hepáticas , MicroRNAs , Paeonia , Extratos Vegetais , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Hep G2 , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Caspase 3/metabolismo , Proteína X Associada a bcl-2 , MicroRNAs/genética , MicroRNAs/metabolismo , Transdução de Sinais , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Apoptose , Proliferação de Células , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , RNA Mensageiro , Luciferases/metabolismo , Luciferases/farmacologia , Linhagem Celular TumoralRESUMO
Enhancing the energy density of layered oxide cathode materials is of great significance for realizing high-performance sodium-ion batteries and promoting their commercial application. Lattice oxygen redox at high voltage usually enables a high capacity and energy density. But the structural degradation, severe voltage decay, and the resultant poor cycling performance caused by irreversible oxygen release seriously restrict the practical application. Herein we introduce a novel fence-type superstructure (2a×3a type supercell) into O3-type layered cathode material Na0.9Li0.1Ni0.3Mn0.3Ti0.3O2 and achieve a stable cycling performance at a high voltage of 4.4â V. The fence-type superstructure effectively inhibits the formation of the vacancy clusters resulting from out-of-plane Li migration and in-plane transition metal migration at high voltage due to the wide d-spacing, thereby significantly reducing the irreversible release of lattice oxygen and greatly stabilizing the crystal structure. The cathode exhibits a high energy density of 545â Wh kg-1, a high rate capability (112.8â mAh g-1 at 5â C) and a high cycling stability (85.8 %@200 cycles with a high initial capacity of 148.6â mAh g-1 at 1â C) accompanied by negligible voltage attenuation (98.5 %@200 cycles). This strategy provides a distinct spacing effect of superstructure to design stable high-voltage layered cathode materials for Na-ion batteries.
RESUMO
The advancement of highly secure and inexpensive aqueous zinc ion energy storage devices is impeded by issues, including dendrite growth, hydrogen evolution and corrosion of zinc anodes. It is essential to modify the interface of zinc anodes that homogenizes ion flux and facilitates highly reversible zinc planarized deposition and stripping. Herein, by coupling zinc ion coordination with acid-base neutralization under the driving of electrophoresis, manageable mesoscopic phase separation for constructing chitosan frameworks was achieved, thereby fabricating interconnected mesoporous chitosan membranes based heterogeneous quasi-solid-state electrolytes integrated with anodes. The framework is constructed by twisted chitosan nanofiber bundles, forming a three-dimensional continuous spindle-shaped pore structure. With this framework, the electrolyte provides exceptional ion conductivity of 25.1â mS cm-1 , with a puncture resistance strength of 2.3â GPa. In addition, the amino groups of chitosan molecule can make the surface of the framework positively charged. Thus, reversible zinc planarized deposition is successfully induced by the synergistic effect of stress constraint and electrostatic modulation. As a result, as-assembled zinc ion capacitor has an excellent cycle life and sustains the capacity by over 95 % after 20000â cycles at a current density of 5â A g-1 . This research presents a constructive strategy for stable electrolytes-integrated zinc anodes.
RESUMO
Polyketides are a major class of natural products, including bioactive medicines such as erythromycin and rapamycin. They are often rich in stereocenters biosynthesized by the ketoreductase (KR) domain within the polyketide synthase (PKS) assembly line. Previous studies have identified conserved motifs in KR sequences that enable the bioinformatic prediction of product stereochemistry. However, the reliability and applicability of these prediction methods have not been thoroughly assessed. In this study, we conducted a comprehensive bioinformatic analysis of 1,762 KR sequences from cis-AT PKSs to reevaluate the residues involved in conferring stereoselectivity. Our findings indicate that the previously identified fingerprint motifs remain valid for KRs in ß-modules from actinobacteria, but their reliability diminishes for KRs from other module types or taxonomic origins. Additionally, we have identified several new motifs that exhibit a strong correlation with the stereochemical outcomes of KRs. These updated fingerprint motifs for stereochemical prediction not only enhance our understanding of the enzymatic mechanisms governing stereocontrol but also facilitate accurate stereochemical prediction and genome mining of polyketides derived from modular cis-AT PKSs.
RESUMO
In the decades since the discovery, Type I interferon (IFN-I) has been intensively studied for their antiviral activity. However, increasing evidences suggest that it may also play an important role in the infection of Toxoplasma gondii, a model organism for intracellular parasites. Recent studies demonstrated that the induction of IFN-I by the parasite depends on cell type, strain genotype, and mouse strain. IFN-I can inhibit the proliferation of T. gondii, but few studies showed that it is beneficial to the growth of the parasite. Meanwhile, T. gondii also can secrete proteins that impact the pathway of IFN-I production and downstream induced interferon-stimulated genes (ISGs) regulation, thereby escaping immune destruction by the host. This article reviews the major findings and progress in the production, function, and regulation of IFN-I during T. gondii infection, to thoroughly understand the innate immune mechanism of T. gondii infection, which provides a new target for subsequent intervention and treatment.
Assuntos
Interferon Tipo I , Toxoplasma , Toxoplasmose , Toxoplasma/imunologia , Animais , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Humanos , Toxoplasmose/imunologia , Toxoplasmose/parasitologia , Interações Hospedeiro-Parasita/imunologia , Imunidade Inata , Transdução de Sinais , Regulação da Expressão Gênica , CamundongosRESUMO
BACKGROUND: As a broad-spectrum tetracycline antibiotic, Oxytetracycline (OTC) was widely used in a variety of applications. But, the overuse of OTC had led to the detection of it in food, water and soil, which could present significance risk to human health and cause damage to ecosystem. It was of great significance to develop sensitive detection methods for OTC. Herein, an environmentally friendly photoelectrochemical (PEC) aptasensor was constructed for the sensitive detection of OTC based on CuO-induced BiOBr/Ag2S/PDA (Polydopamine) photocurrent polarity reversal. RESULTS: BiOBr/Ag2S/PDA composites modified electrode not only produced stable initial anodic photocurrent but also provided attachment sites for the aptamer S1 of OTC by the strong adhesion of PDA. On the other hand, CuO loaded OTC aptamer S2 (Cu-S2) was got through Cu-S bonds. After the target OTC was identified on the electrode surface, CuO was introduced to the surface of ITO/BiOBr/Ag2S/PDA through the specific binding of OTC to S2. This identification process formed dual Z-type heterojunctions and resulted in a remarkable reversal of photocurrent polarity from anodic to cathodic. Under optimization conditions, the PEC aptasensor showed a wide linear range (50 fM â¼ 100 nM), low detection limit (1.9 fM), excellent selectivity, stability and reproducibility for the detection of OTC. Moreover, it was successfully used for the analysis of OTC in real samples of tap water, milk and honey, and had the potential for practical application. SIGNIFICANCE: This work developed an environmentally friendly photocurrent-polarity-switching PEC aptasensor with excellent selectivity, reproducibility, stability, low LOD and wide linear range for OTC detection. This sensitive system, which was including BiOBr, Ag2S, PDA and CuO were low toxicity, not only reduced the risk of traditional toxic semiconductors to operators and the environment, but can also be used for the detection of real samples, broadening the wider range of applications for BiOBr, Ag2S, PDA and CuO.