ABSTRACT
Modifying catalyst surface with small molecular-additives presents a promising avenue for enhancing electrocatalytic performance. However, challenges arise in preserving the molecular-additives and maximizing their tuning effect, particularly at high current-densities. Herein, we develop an effective strategy to preserve the molecular-additives on electrode surface by applying a thin protective layer. Taking 4-dimethylaminopyridine (DMAP) as an example of a molecular-additive, the hydrophobic protection layer on top of the DMAP-functionalized Cu-catalyst effectively prevents its leaching during CO2 electroreduction (CO2R). Consequently, the confined DMAP molecules substantially promote the CO2-to-multicarbon conversion at low overpotentials. For instance, at a potential as low as -0.47 V vs. reversible hydrogen electrode, the DMAP-functionalized Cu exhibits over 80% selectivity towards multi-carbon products, while the pristine Cu shows only ~35% selectivity for multi-carbon products. Notably, ethanol appears as the primary product on DMAP-functionalized Cu, with selectivity approaching 50% at a high current density of 400 mA cm-2. Detailed kinetic analysis, in-situ spectroscopies, and theoretical calculations indicate that DMAP-induced electron accumulations on surface Cu-sites decrease the reaction energy for C-C coupling. Additionally, the interactions between DMAP and oxygenated intermediates facilitate the ethanol formation pathway in CO2R. Overall, this study showcases an effective strategy to guide future endeavors involving molecular tuning effects.
ABSTRACT
The ethylene-regulated hypocotyl elongation of Arabidopsis thaliana involves many transcription factors. The specific role of MYC transcription factors in ethylene signal transduction is not completely understood. The results here revealed that two MYCs, MYC2 and MYC3, act as negative regulators in ethylene-suppressed hypocotyl elongation. Etiolated seedlings of the loss-of-function mutant of MYC2 or MYC3 were significantly longer than wild-type seedlings. Single- or double-null mutants of MYC2 and MYC3 displayed remarkably enhanced response to ACC(1-aminocyclopropane-1-carboxylate), the ethylene precursor, compared to wild-type seedlings. MYC2 and MYC3 directly bind to the promoter zone of ERF1, strongly suppressing its expression. Additionally, EIN3, a key component in ethylene signaling, interacts with MYC2 or MYC3 and significantly suppresses their binding to ERF1's promoter. MYC2 and MYC3 play crucial roles in the ethylene-regulated expression of functional genes. The results revealed the novel role and functional mechanism of these transcription factors in ethylene signal transduction. The findings provide valuable information for deepening our understanding of their role in regulating plant growth and responding to stress.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Ethylenes , Gene Expression Regulation, Plant , Hypocotyl , Promoter Regions, Genetic , Transcription Factors , Arabidopsis/genetics , Arabidopsis/growth & development , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Ethylenes/metabolism , Hypocotyl/growth & development , Hypocotyl/genetics , Hypocotyl/metabolism , Transcription Factors/metabolism , Transcription Factors/genetics , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/genetics , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/metabolism , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Seedlings/growth & development , Seedlings/genetics , Seedlings/metabolism , Signal Transduction , Basic-Leucine Zipper Transcription Factors/metabolism , Basic-Leucine Zipper Transcription Factors/genetics , Peptide Termination Factors , Trans-ActivatorsABSTRACT
Transition metal-nitrogen-carbon complexes, featuring single metal atoms embedded in a nitrogen-doped carbon matrix, emerge as promising alternatives to traditional platinum-based catalysts, offering cost-effectiveness, abundance, and enhanced catalytic performance. This work introduces a novel method for the etching and doping of zeolitic imidazolate frameworks (ZIFs) with transition metals, creating a uniform distribution of secondary metal centers on ZIF surfaces. By disrupting the crystalline symmetry of ZIFs through synthetic defect engineering, we gain access to their entire internal volume, creating multichannel pathways. The absorption of metal ions is theoretically simulated, demonstrating their thermodynamically spontaneous nature. The selective removal of defect channels under Lewis acidic conditions, induced by metal ion alcoholysis/hydrolysis, facilitates the introduction of metal atoms into ZIF cavities. The resulting single-atom catalyst, after pyrolysis, features a three-dimensional (3D) multichannel structure, high surface area, and uniformly dispersed metal atoms within the N-doped carbon matrix, establishing it as an exceptional catalyst for the oxygen reduction reaction (ORR). Our findings highlight the potential of using metal etching in defect-engineered metal-organic frameworks (MOFs) for single-atom catalyst preparation, paving the way for the next generation of high-performance, cost-effective ORR catalysts in sustainable energy systems.
ABSTRACT
OBJECTIVES: We aimed to explore the effects and mechanisms of action of dehydroepiandrosterone (DHEA) on immune evasion of oral squamous cell carcinoma (OSCC) to provide evidence for enhancing the effect of immunotherapy. MATERIALS AND METHODS: A xenograft mouse model and immunohistochemistry were used to reveal the patterns of tumor-infiltrating lymphocytes (TILs). The CAL27 and SCC VII cell lines were used for the in vitro study. Western blotting, qPCR, immunofluorescence, and flow cytometry were used to evaluate the expression of B7-H4. Recombinant mouse B7-H4 protein (rmB7-H4) and PG490, an inhibitor of NF-κB p65 were used for the "rescue study." Gain- and loss-of-function, luciferase reporter, and chromatin immunoprecipitation assays were performed to verify this mechanism. RESULTS: DHEA inhibited tumor growth in an OSCC xenograft mouse model, increased CD8 + cells, and decreased FOXP3 + cells in TILs. DHEA reduced the expression of B7-H4 in CAL27 and SCC VII cells RmB7-H4 reverses the effect of DHEA on tumor growth and TIL patterns. DHEA increased the expression of miR-15b-5p and activated its transcriptional factor NF-κB p65. Further experiments demonstrated that miR-15b-5p inhibited B7-H4 expression by binding to its 3'-UTR regions, and NF-κB p65 activated miR-15b transcription. PG490 reversed the effects of DHEA on tumor growth, antitumor immunity in the OSCC xenograft model, and the expression/phosphorylation of NF-κB p65, miR-15b-5p, and B7-H4. CONCLUSIONS: This study indicates that DHEA attenuates the immune escape of OSCC cells by inhibiting B7-H4 expression, providing new insights for cancer immunotherapy.
Subject(s)
Carcinoma, Squamous Cell , Dehydroepiandrosterone , MicroRNAs , Mouth Neoplasms , Transcription Factor RelA , Tumor Escape , V-Set Domain-Containing T-Cell Activation Inhibitor 1 , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , Mouth Neoplasms/immunology , Mouth Neoplasms/drug therapy , Humans , Transcription Factor RelA/metabolism , Dehydroepiandrosterone/pharmacology , Dehydroepiandrosterone/therapeutic use , Tumor Escape/drug effects , Cell Line, Tumor , V-Set Domain-Containing T-Cell Activation Inhibitor 1/genetics , V-Set Domain-Containing T-Cell Activation Inhibitor 1/metabolism , Mice , Carcinoma, Squamous Cell/immunology , Carcinoma, Squamous Cell/drug therapy , Xenograft Model Antitumor Assays , Gene Expression Regulation, Neoplastic/drug effects , Signal Transduction/drug effects , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/drug effects , Mice, Inbred BALB C , Mice, NudeABSTRACT
BACKGROUND: This study investigated the effect of carbodiimide (EDC) combined with Clearfil SE self-etch adhesive on the shear bond strength (SBS), crosslinking degree, denaturation temperature, and enzyme activity of dentin in vitro. MATERIALS AND METHODS: Collected human sound third molars were randomly divided into different groups with or without EDC treatment (0.01-1 M). The specimens (n = 16)were stored for 24 h (immediate) or 12 months (aging) before testing the SBS. Fine dentin powder was obtained and treated with the same solutions. Then the crosslinking degree, denaturation temperature (Td), and enzyme activity were tested. Statistical analysis was performed using a one-way analysis of variance (ANOVA) to compare the differences of data between groups (α = 0.05). RESULTS: There was a significant drop in immediate SBS and more adhesive fracture of 1.0 M EDC group, while there were no significant differences among the other groups. SEM showed a homogeneous interface under all treatments. After 12 months of aging, the SBS significantly decreased. Less decreases of SBS in the 0.3 and 0.5 M groups were found. Due to thermal and enzymatical properties consideration, the 0.3 and 0.5 M treatments also showed higher cross-link degree and Td with lower enzyme activity. CONCLUSION: 0.3 and 0.5 M EDC may be favorable for delaying the aging of self-etch bond strength for 12 months. But it is still needed thoroughly study.
Subject(s)
Carbodiimides , Resin Cements , Shear Strength , Humans , Carbodiimides/chemistry , Resin Cements/chemistry , Materials Testing , Dentin , Microscopy, Electron, Scanning , Dentin-Bonding Agents/chemistry , Dental Stress Analysis , Cross-Linking Reagents/chemistry , Dental Bonding/methods , In Vitro Techniques , Acid Etching, Dental/methods , Molar, Third , Temperature , Time Factors , Surface PropertiesABSTRACT
We report the free energy barriers for the elementary reactions in the 2e- and 4e- oxygen reduction reaction (ORR) steps on Au(100) in an alkaline solution. Due to the weak adsorption energy of O2 on Au(100), the barrier for the association channel is very low, and the 2e- pathway is clearly favored, while the barrier for the O-O dissociation channel is significantly higher at 0.5 eV. Above 0.7 V reversible hydrogen electrode (RHE), the association channel becomes thermodynamically unfavorable, which opens up the O-O dissociation channel, leading to the 4e- pathway. The low adsorption energy of oxygenated species on Au is now an advantage, and residue ORR current can be observed up to the 1.0-1.2 V region (RHE). In contrast, the O-O dissociation barrier on Au(111) is significantly higher, at close to 0.9 eV, due to coupling with surface reorganization, which explains the lower ORR activity on Au(111) than that on Au(100). In combination with the previously suggested outer sphere electron transfer to O2 for its initial adsorption, these results provide a consistent explanation for the features in the experimentally measured polarization curve for the alkaline ORR on Au(100) and demonstrate an ORR mechanism distinct from that on Pt(111). It also highlights the importance to consider the spin state of O2 in ORR and to understand the activation barriers, in addition to the adsorption energies, to account for the features observed in electrochemical measurements.
ABSTRACT
Background: Hepatic Ischemia-Reperfusion Injury (HIRI) is a major complication in liver transplants and surgeries, significantly affecting postoperative outcomes. The role of mitophagy, essential for removing dysfunctional mitochondria and maintaining cellular balance, remains unclear in HIRI. Methods: To unravel the role of mitophagy-related genes (MRGs) in HIRI, we assembled a comprehensive dataset comprising 44 HIRI samples alongside 44 normal control samples from the Gene Expression Omnibus (GEO) database for this analysis. Using Random Forests and Support Vector Machines - Recursive Feature Elimination (SVM-RFE), we pinpointed eight pivotal genes and developed a logistic regression model based on these findings. Further, we employed consensus cluster analysis for classifying HIRI patients according to their MRG expression profiles and conducted weighted gene co-expression network analysis (WGCNA) to identify clusters of genes that exhibit high correlation within different modules. Additionally, we conducted single-cell RNA sequencing data analysis to explore insights into the behavior of MRGs within the HIRI. Results: We identified eight key genes (FUNDC1, VDAC1, MFN2, PINK1, CSNK2A2, ULK1, UBC, MAP1LC3B) with distinct expressions between HIRI and controls, confirmed by PCR validation. Our diagnostic model, based on these genes, accurately predicted HIRI outcomes. Analysis revealed a strong positive correlation of these genes with monocytic lineage and a negative correlation with B and T cells. HIRI patients were divided into three subclusters based on MRG profiles, with WGCNA uncovering highly correlated gene modules. Single-cell analysis identified two types of endothelial cells with different MRG scores, indicating their varied roles in HIRI. Conclusions: Our study highlights the critical role of MRGs in HIRI and the heterogeneity of endothelial cells. We identified the macrophage migration inhibitory factor (MIF) and cGAS-STING (GAS) pathways as regulators of mitophagy's impact on HIRI. These findings advance our understanding of mitophagy in HIRI and set the stage for future research and therapeutic developments.
Subject(s)
Endothelial Cells , Liver , Mitophagy , Reperfusion Injury , Humans , Mitophagy/genetics , Reperfusion Injury/genetics , Reperfusion Injury/metabolism , Endothelial Cells/metabolism , Liver/metabolism , Liver/pathology , Gene Expression Profiling , Male , Gene Regulatory Networks , Transcriptome , FemaleABSTRACT
The enhanced permeability and retention (EPR) effect has become the guiding principle for nanomedicine against cancer for a long time. However, several biological barriers severely resist therapeutic agents' penetration and retention into the deep tumor tissues, resulting in poor EPR effect and high tumor mortality. Inspired by lava, we proposed a proteolytic enzyme therapy to improve the tumor distribution and penetration of nanomedicine. A trypsin-crosslinked hydrogel (Trypsin@PSA Gel) was developed to maintain trypsin's activity. The hydrogel postponed trypsin's self-degradation and sustained the release. Trypsin promoted the cellular uptake of nanoformulations in breast cancer cells, enhanced the penetration through endothelial cells, and degraded total and membrane proteins. Proteomic analysis reveals that trypsin affected ECM components and down-regulated multiple pathways associated with cancer progression. Intratumoral injection of Trypsin@PSA Gel significantly increased the distribution of liposomes in tumors and reduced tumor vasculature. Combination treatment with intravenous injection of gambogic acid-loaded liposomes and intratumoral injection of Trypsin@PSA Gel inhibited tumor growth. The current study provides one of the first investigations into the enhanced tumor distribution of liposomes induced by a novel proteolytic enzyme therapy.
Subject(s)
Hydrogels , Liposomes , Polyethylene Glycols , Trypsin , Xanthones , Liposomes/chemistry , Animals , Polyethylene Glycols/chemistry , Hydrogels/chemistry , Humans , Trypsin/metabolism , Trypsin/chemistry , Female , Mice , Cell Line, Tumor , Mice, Inbred BALB C , Breast Neoplasms/drug therapy , ProteolysisABSTRACT
Aim: To elucidate dynamics and functions in colonic macrophage subsets, and their regulation by Bifidobacterium breve (B. breve) and its associated metabolites in the initiation of colitis-associated colorectal cancer (CAC). Methods: Azoxymethane (AOM) and dextran sodium sulfate (DSS) were used to create a CAC model. The tumor-suppressive effect of B. breve and variations of macrophage subsets were evaluated. Intestinal macrophages were ablated to determine their role in the protective effects of B. breve. Efficacious molecules produced by B. breve were identified by non-targeted and targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The molecular mechanism was further verified in murine bone marrow-derived macrophages (BMDMs), macrophages derived from human peripheral blood mononuclear cells (hPBMCs), and demonstrated in CAC mice. Results: B. breve alleviated colitis symptoms, delayed colonic tumorigenesis, and promoted phenotypic differentiation of immature inflammatory macrophages into mature homeostatic macrophages. On the contrary, the ablation of intestinal macrophages largely annulled the protective effects of B. breve. Microbial analysis of colonic contents revealed the enrichment of probiotics and the depletion of potential pathogens following B. breve supplementation. Moreover, indole-3-lactic acid (ILA) was positively correlated with B. breve in CAC mice and highly enriched in the culture supernatant of B. breve. Also, the addition of ILA directly promoted AKT phosphorylation and restricted the pro-inflammatory response of murine BMDMs and macrophages derived from hPBMCs in vitro. The effects of ILA in murine BMDMs and macrophages derived from hPBMCs were abolished by the aryl hydrocarbon receptor (AhR) antagonist CH-223191 or the AKT inhibitor MK-2206. Furthermore, ILA could protect against tumorigenesis by regulating macrophage differentiation in CAC mice; the AhR antagonist largely abrogated the effects of B. breve and ILA in relieving colitis and tumorigenesis. Conclusion: B. breve-mediated tryptophan metabolism ameliorates the precancerous inflammatory intestinal milieu to inhibit tumorigenesis by directing the differentiation of immature colonic macrophages.
Subject(s)
Bifidobacterium breve , Cell Differentiation , Colitis , Indoles , Macrophages , Probiotics , Animals , Mice , Macrophages/metabolism , Macrophages/drug effects , Bifidobacterium breve/metabolism , Indoles/pharmacology , Indoles/metabolism , Humans , Colitis/chemically induced , Colitis/microbiology , Colitis/complications , Cell Differentiation/drug effects , Probiotics/pharmacology , Probiotics/administration & dosage , Disease Models, Animal , Carcinogenesis/drug effects , Colitis-Associated Neoplasms/pathology , Colitis-Associated Neoplasms/microbiology , Colitis-Associated Neoplasms/metabolism , Mice, Inbred C57BL , Colon/microbiology , Colon/pathology , Colon/metabolism , Dextran Sulfate , Male , Gastrointestinal Microbiome , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/microbiology , AzoxymethaneABSTRACT
Cancer stem cells (CSCs) drive malignant tumor progression, recurrence, and metastasis with unique characteristics, including self-renewal and resistance to conventional treatments. Conventional differentiation inducers, although promising, have limited cytotoxicity and may inadvertently enhance CSC stemness. To address these challenges, ongoing efforts are dedicated to developing strategies that can effectively combine both cytotoxicity and differentiation-inducing effects. In this study, we introduce oridonin (Ori), a small molecule with dual differentiation-inducing and cytotoxicity properties capable of eliminating tumor CSCs. We isolated CSCs in B16F10 cells using the Hoechst side population method and assessed the differentiation effect of Ori. Ori's differentiation-inducing effect was further evaluated using human acute promyelocytic leukemia. The cytotoxic potential of Ori against MCF-7 and B16F10 cell lines was assessed through various methods. In vivo anti-tumor and anti-CSC efficacy of Ori was investigated using mouse melanoma and CSCs melanoma models. Safety evaluation included zebrafish embryotoxicity and mouse acute toxicity experiments. As a result, Ori effectively dismantles tumorspheres, inhibits proliferation, and reduces the expression of CSC-specific markers. It induces significant differentiation, especially in the case of NB4. Additionally, Ori upregulates TP53 expression, mitigates the hypoxic tumor microenvironment, suppresses stemness, and inhibits PD-L1 expression, prompting a robust anti-cancer immune response. Ori demonstrates pronounced cytotoxicity, inducing notable pro-apoptotic effects on B16F10 and MCF-7 cells, with specific triggering of mitochondrial apoptosis. Importantly, Ori maintains a commendable biosafety record. The dual-action prowess of Ori not only induces the differentiation of CSCs but also dispatches differentiated and residual tumor cells, effectively thwarting the relentless march of tumor progression.
Subject(s)
Cell Differentiation , Diterpenes, Kaurane , Neoplastic Stem Cells , Zebrafish , Diterpenes, Kaurane/pharmacology , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/pathology , Animals , Humans , Cell Differentiation/drug effects , Mice , Cell Line, Tumor , Cell Proliferation/drug effects , Apoptosis/drug effects , Antineoplastic Agents/pharmacology , Tumor Suppressor Protein p53/metabolism , MCF-7 Cells , Melanoma, Experimental/pathology , Melanoma, Experimental/drug therapy , Leukemia, Promyelocytic, Acute/pathology , Leukemia, Promyelocytic, Acute/drug therapy , FemaleABSTRACT
OBJECTIVE: To explore the clinical phenotype and genetic characteristics of a Chinese pedigree affected with Spastic paraplegia type 5A (SPG5A). METHODS: A pedigree suspected for Hereditary spastic paraplegia (HSP) at Henan Children's Hospital on August 15 2022 was selected as the study subject. Clinical data of the pedigree was collected. Peripheral blood samples were collected from members of the pedigree. Following extraction of genomic DNA, trio-WGS was carried out, and candidate variant was verified by Sanger sequencing. RESULTS: The child, a 1-year-old boy, had presented with microcephaly, hairy face and dorsal side of distal extremities and trunk, intellectual and motor development delay, increased muscle tone of lower limbs, hyperreflexes of bilateral knee tendons, and positive pathological signs. His parents and sister both had normal phenotypes. Trio-WGS revealed that the child has harbored a homozygous c.1250G>A (p.Arg417His) variant of the CYP7B1 gene, for which his mother was heterozygous, the father and sister were of the wild type. The variant was determined to have originated from maternal uniparental disomy (UPD). The result of Sanger sequencing was in keeping with the that of trio-WGS. SPG5A due to maternal UPD of chromosome 8 was unreported previously. CONCLUSION: The child was diagnosed with SPG5A, a complex type of HSP, for which the homozygous c.1250G>A variant of the CYP7B1 gene derived from maternal UPD may be accountable.
Subject(s)
Spastic Paraplegia, Hereditary , Humans , Infant , Male , China , Mutation , Paraplegia/genetics , Pedigree , Phenotype , Spastic Paraplegia, Hereditary/geneticsABSTRACT
Despite the advances of multistep enzymatic cascade reactions, their incorporation with abiotic reactions in living organisms remains challenging in synthetic biology. Herein, we combined microbial metabolic pathways and Pd-catalyzed processes for in-situ generation of bioactive conjugated oligomers. Our biocompatible one-pot coupling reaction utilized the fermentation process of engineered E. coli that converted glucose to styrene, which participated in the Pd-catalyzed Heck reaction for in-situ synthesis of conjugated oligomers. This process serves a great interest in understanding resistance evolution by utilizing the inhibitory activity of the synthesized conjugated oligomers. The approach allows for the in-situ combination of biological metabolism and CC coupling reactions, opening up new possibilities for the biosynthesis of unnatural molecules and enabling the in-situ regulation of the bioactivity of the obtained products.
Subject(s)
Escherichia coli , Palladium , Escherichia coli/metabolism , Catalysis , FermentationABSTRACT
Hemicellulose is mainly distributed in the tightly packed S2 layer of the plant cell wall and the middle lamella. This rigid microstructure of wood and interactions among hemicellulose, lignin, and cellulose jointly restrict the separation and transformation of hemicellulose in the wood matrix. To address this issue, a method combined with microwave-expanding pretreatment (MEP) and microwave-assisted extraction (MAE) with a NaOH solution was carried out. We found that the MEP could effectively create new pathways for bagasse cells in mass transferring. More specifically, 195 % of the specific surface area (m2/g) with 193 % of the pores (>50 nm) increased after MEP; the SEM images also confirmed that the microstructure of bagasse was modified. MAE could considerably exfoliate hemicellulose from cellulose fiber and accelerate mass transfer. Additionally, we optimized MEP and MAE by using response surface methodology (RSM). The optimal parameters were 370 K, 3.7 min, 1081 W microwave power, and 9.9 wt% NH4HCO3 consumption for the MEP and 1100 W microwave power, 2.5 wt% NaOH concentration, 34.6 min reaction time for MAE, respectively. Moreover, molecular dynamics (MD) simulation suggests that NaOH could significantly lower the work needed to peel off the xylan chain from cellulose nanofibril.
Subject(s)
Cellulose , Microwaves , Polysaccharides , Sodium Hydroxide , Cellulose/chemistryABSTRACT
OBJECTIVE: To explore the effects of different polymers on in vitro biomimetic mineralization of small intestinal submucosa (SIS) scaffolds, and to evaluate the physicochemical properties and biocompatibility of the SIS scaffolds. METHODS: The SIS scaffolds prepared by freeze-drying method were immersed in simulated body fluid (SBF), mineralized liquid containing polyacrylic acid (PAA) and mine-ralized liquid containing PAA and polyaspartic acid (PASP). After two weeks in the mineralized solution, the liquid was changed every other day. SBF@SIS, PAA@SIS, PAA/PASP@SIS scaffolds were obtained. The SIS scaffolds were used as control group to evaluate their physicochemical properties and biocompatibility. We observed the bulk morphology of the scaffolds in each group, analyzed the microscopic morphology by environment scanning electron microscopy and determined the porosity and pore size. We also analyzed the surface elements by energy dispersive X-ray spectroscopy (EDX), analyzed the structure of functional groups by Flourier transformed infrared spectroscopy (FTIR), detected the water absorption rate by using specific gravity method, and evaluated the compression strength by universal mechanical testing machine. The pro-cell proliferation effect of each group of scaffolds were evaluated by CCK-8 cell proliferation method. RESULTS: Under scanning electron microscopy, the scaffolds of each group showed a three-dimensional porous structure with suitable pore size and porosity, and crystal was observed in all the mineralized scaffolds of each group, in which the crystal deposition of PAA/PASP@SIS scaffolds was more regular. At the same time, the collagen fibers could be seen to thicken. EDX analysis showed that the characteristic peaks of Ca and P were found in the three groups of mineralized scaffolds, and the highest peaks were found in the PAA/PASP@SIS scaffolds. FTIR analysis proved that all the three groups of mineralized scaffolds were able to combine hydroxyapatite with SIS. All the scaffolds had good hydrophilicity. The compressive strength of the mineralized scaffold in the three groups was higher than that in the control group, and the best compressive strength was found in PAA/PASP@SIS scaffold. The scaffolds of all the groups could effectively adsorb proteins, and PAA/PASP@SIS group had the best adsorption capacity. In the CCK-8 cell proliferation experiment, the PAA/PASP@SIS scaffold showed the best ability to promote cell proliferation with the largest number of living cells observed. CONCLUSION: Compared with other mineralized scaffolds, PAA/PASP@SIS scaffolds prepared by mineralized solution containing both PAA and PASP have better physicochemical properties and biocompatibility and have potential applications in bone tissue engineering.
Subject(s)
Polymers , Tissue Scaffolds , Tissue Scaffolds/chemistry , Polymers/chemistry , Biomimetics , Sincalide , Tissue Engineering/methods , Intestine, Small , PorosityABSTRACT
The electrochemical conversion of nitrate to ammonia is a way to eliminate nitrate pollutant in water. Cu-Co synergistic effect was found to produce excellent performance in ammonia generation. However, few studies have focused on this effect in high-entropy oxides. Here, we report the spin-related Cu-Co synergistic effect on electrochemical nitrate-to-ammonia conversion using high-entropy oxide Mg0.2Co0.2Ni0.2Cu0.2Zn0.2O. In contrast, the Li-incorporated MgCoNiCuZnO exhibits inferior performance. By correlating the electronic structure, we found that the Co spin states are crucial for the Cu-Co synergistic effect for ammonia generation. The Cu-Co pair with a high spin Co in Mg0.2Co0.2Ni0.2Cu0.2Zn0.2O can facilitate ammonia generation, while a low spin Co in Li-incorporated MgCoNiCuZnO decreases the Cu-Co synergistic effect on ammonia generation. These findings offer important insights in employing the synergistic effect and spin states inside for selective catalysis. It also indicates the generality of the magnetic effect in ammonia synthesis between electrocatalysis and thermal catalysis.
ABSTRACT
Photocatalytic overall water splitting into hydrogen and oxygen is desirable for long-term renewable, sustainable and clean fuel production on earth. Metal sulfides are considered as ideal hydrogen-evolved photocatalysts, but their component homogeneity and typical sulfur instability cause an inert oxygen production, which remains a huge obstacle to overall water-splitting. Here, a distortion-evoked cation-site oxygen doping of ZnIn2S4 (D-O-ZIS) creates significant electronegativity differences between adjacent atomic sites, with S1 sites being electron-rich and S2 sites being electron-deficient in the local structure of S1-S2-O sites. The strong charge redistribution character activates stable oxygen reactions at S2 sites and avoids the common issue of sulfur instability in metal sulfide photocatalysis, while S1 sites favor the adsorption/desorption of hydrogen. Consequently, an overall water-splitting reaction has been realized in D-O-ZIS with a remarkable solar-to-hydrogen conversion efficiency of 0.57%, accompanying a ~ 91% retention rate after 120 h photocatalytic test. In this work, we inspire an universal design from electronegativity differences perspective to activate and stabilize metal sulfide photocatalysts for efficient overall water-splitting.
ABSTRACT
Oomycete pathogens secrete numerous crinkling and necrosis proteins (CRNs) to manipulate plant immunity and promote infection. However, the functional mechanism of CRN effectors is still poorly understood. Previous research has shown that the Phytophthora sojae effector PsCRN108 binds to the promoter of HSP90s and inhibits their expression, resulting in impaired plant immunity. In this study, we found that in addition to HSP90, PsCRN108 also suppressed other Heat Shock Protein (HSP) family genes, including HSP40. Interestingly, PsCRN108 inhibited the expression of NbHSP40 through its promoter, but did not directly bind to its promoter. Instead, PsCRN108 interacted with NbCAMTA2, a negative regulator of plant immunity. NbCAMTA2 was a negative regulator of NbHSP40 expression, and PsCRN108 could promote such inhibition activity of NbCAMTA2. Our results elucidated the multiple roles of PsCRN108 in the suppression of plant immunity and revealed a new mechanism by which the CRN effector hijacked transcription factors to affect immunity. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
Subject(s)
Phytophthora , Phytophthora/genetics , Reactive Oxygen Species/metabolism , Transcription Factors/metabolism , Heat-Shock Proteins/metabolism , Plant Immunity , Plant DiseasesABSTRACT
As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants continue to wreak havoc worldwide, the "Cytokine Storm" (CS, also known as the inflammatory storm) or Cytokine Release Syndrome has reemerged in the public consciousness. CS is a significant contributor to the deterioration of infected individuals. Therefore, CS control is of great significance for the treatment of critically ill patients and the reduction of mortality rates. With the occurrence of variants, concerns regarding the efficacy of vaccines and antiviral drugs with a broad spectrum have grown. We should make an effort to modernize treatment strategies to address the challenges posed by mutations. Thus, in addition to the requirement for additional clinical data to monitor the long-term effects of vaccines and broad-spectrum antiviral drugs, we can use CS as an entry point and therapeutic target to alleviate the severity of the disease in patients. To effectively combat the mutation, new technologies for neutralizing or controlling CS must be developed. In recent years, nanotechnology has been widely applied in the biomedical field, opening up a plethora of opportunities for CS. Here, we put forward the view of cytokine storm as a therapeutic target can be used to treat critically ill patients by expounding the relationship between coronavirus disease 2019 (COVID-19) and CS and the mechanisms associated with CS. We pay special attention to the representative strategies of nanomaterials in current neutral and CS research, as well as their potential chemical design and principles. We hope that the nanostrategies described in this review provide attractive treatment options for severe and critical COVID-19 caused by CS.
Subject(s)
COVID-19 , Vaccines , Humans , Cytokine Release Syndrome/drug therapy , SARS-CoV-2 , Critical Illness , Cytokines , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic useABSTRACT
Recent studies have suggested that long-term application of anti-angiogenic drugs may impair oral mucosal wound healing. This study investigated the effect of sunitinib on oral mucosal healing impairment in mice and the therapeutic potential of Bifidobacterium breve (B. breve). A mouse hard palate mucosal defect model was used to investigate the influence of sunitinib and/or zoledronate on wound healing. The volume and density of the bone under the mucosal defect were assessed by micro-computed tomography (micro-CT). Inflammatory factors were detected by protein microarray analysis and enzyme-linked immunosorbent assay (ELISA). The senescence and biological functions were tested in oral mucosal stem cells (OMSCs) treated with sunitinib. Ligated loop experiments were used to investigate the effect of oral B. breve. Neutralizing antibody for interleukin-10 (IL-10) was used to prove the critical role of IL-10 in the pro-healing process derived from B. breve. Results showed that sunitinib caused oral mucosal wound healing impairment in mice. In vitro, sunitinib induced cellular senescence in OMSCs and affected biological functions such as proliferation, migration, and differentiation. Oral administration of B. breve reduced oral mucosal inflammation and promoted wound healing via intestinal dendritic cells (DCs)-derived IL-10. IL-10 reversed cellular senescence caused by sunitinib in OMSCs, and IL-10 neutralizing antibody blocked the ameliorative effect of B. breve on oral mucosal wound healing under sunitinib treatment conditions. In conclusion, sunitinib induces cellular senescence in OMSCs and causes oral mucosal wound healing impairment and oral administration of B. breve could improve wound healing impairment via intestinal DCs-derived IL-10.
Subject(s)
Bifidobacterium breve , Interleukin-10 , Animals , Mice , Up-Regulation , Angiogenesis Inhibitors , Sunitinib , X-Ray Microtomography , Administration, Oral , Wound Healing , Antibodies, NeutralizingABSTRACT
Atomically dispersed single-atom catalysts are intriguing catalysts in the field of electrocatalysis for nearly 100% exploitation of metal atoms. However, they are still far from practical usage due to the scaling relationship limit and metal loading limit. Generation of a diatomic complex would offer superior catalytic performance through the cooperation of two neighboring atoms as active sites. Herein, Fe/Co dual atomic sites embedded in a tube-on-plate hollow structure are designed and fabricated for an efficient electrochemical oxygen reduction reaction (ORR). The unique structure composed of ultrathin nanotube building blocks dramatically maximizes the surface area for copious active site exposure. Thanks to the synergetic interaction between Fe/Co pairs, the obtained FeCo/NC exhibits outstanding ORR activity and stability in alkaline media. Furthermore, density functional theory calculations have revealed that the remarkable activity is attributed to the electron-deficient Fe sites in FeCoN6. This work may pave the way for the innovative design of highly dispersed dual-site catalysts for broader applications in the realm of electrochemical catalysis.