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1.
ACS Appl Mater Interfaces ; 16(25): 32160-32168, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38870105

RESUMO

Electrocatalytic nitrogen reduction reaction (NRR) is considered to be a viable contender for the production of NH3. However, due to the sluggish adsorption and activation of the electrocatalyst toward inert N2 molecules, there is an urgent need for developing effective catalysts to facilitate the reaction. Inspired by natural nitrogenase, in which Mo atoms are the active centers, Mo-based electrocatalysts have received considerable attention, but further exploration is still necessary. Interface-engineered electrocatalysts can effectively optimize the absorption and activation of the catalytic active center for N2 and thus improve the electrocatalytic activity of NRR. However, the lack of studies for controllably constructing an optimal ratio of two phases at the interface hinders the development of NRR electrocatalysts. Herein, a series of Mo2C/MoO2 interface-engineered electrocatalysts with various Mo2C/MoO2 ratios were constructed by controlling the Y dosages. The controlled experimental results verified that the catalytic activity of NRR, the dosage of Y, and the ratio of Mo2C/MoO2 were strongly correlated. Density functional theory calculations show that the C-Mo-O coordination at the Mo2C/MoO2 interface can optimize the reaction path and reduce the energy barrier of the reaction intermediates, thereby enhancing the reaction kinetics of NRR.

2.
Carbohydr Polym ; 339: 122214, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823900

RESUMO

The polysaccharide, RGP2, was isolated from Russula griseocarnosa and its immunostimulatory effects were confirmed in cyclophosphamide (CTX)-induced immunosuppressed mice. Following purification via chromatography, structural analysis revealed that RGP2 had a molecular weight of 11.82 kDa and consisted of glucose (Glc), galactose (Gal), mannose, glucuronic acid and glucosamine. Bond structure analysis and nuclear magnetic resonance characterization confirmed that the main chain of RGP2 was formed by →6)-ß-D-Glcp-(1→, →3)-ß-D-Glcp-(1→ and →6)-α-D-Galp-(1→, which was substituted at O-3 of →6)-ß-D-Glcp-(1→ by ß-D-Glcp-(1→. RGP2 was found to ameliorate pathological damage in the spleen and enhance immune cell activity in immunosuppressed mice. Based on combined multiomics analysis, RGP2 altered the abundance of immune-related microbiota (such as Lactobacillus, Faecalibacterium, and Bacteroides) in the gut and metabolites (uridine, leucine, and tryptophan) in the serum. Compared with immunosuppressed mice, RGP2 also restored the function of antigen-presenting cells, promoted the polarization of macrophages into the M1 phenotype, positively affected the differentiation of helper T cells, and inhibited regulatory T cell differentiation through the protein kinase B (AKT)/mechanistic target of rapamycin (mTOR) pathway, ultimately exerting an immune boosting function. Overall, our findings highlight therapeutic strategies to alleviate CTX-induced immunosuppression in a clinical setting.


Assuntos
Basidiomycota , Diferenciação Celular , Glucanos , Animais , Camundongos , Basidiomycota/química , Glucanos/química , Glucanos/farmacologia , Glucanos/isolamento & purificação , Diferenciação Celular/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Agentes de Imunomodulação/farmacologia , Agentes de Imunomodulação/química , Masculino , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Ciclofosfamida/farmacologia , Camundongos Endogâmicos BALB C , Microbioma Gastrointestinal/efeitos dos fármacos
3.
Ultrason Sonochem ; 107: 106912, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38762940

RESUMO

The United Nations' Sustainable Development Goals (SDGs) are significant in guiding modern scientific research. In recent years, scholars have paid much attention to MOFs materials as green materials. However, piezo catalysis of MOFs materials has not been widely studied. Piezoelectric materials can convert mechanical energy into electrical energy, while MOFs are effective photocatalysts for removing pollutants. Therefore, it is crucial to design MOFs with piezoelectric properties and photosensitivity. In this study, sulfur-functionalized metal-organic frameworks (S-MOFs) were prepared using organic sulfur-functionalized ligand (H2TDC) ultrasonic synthesis to enhance their piezoelectric properties and visible light absorption. The study demonstrated that the S-MOFs significantly enhanced the reduction of a 10 mg/L solution of hexavalent chromium to 99.4 % within 10 min, using only 15 mg of catalyst. The orbital energy level differences of the elements were analyzed using piezo response force microscopy (PFM) and X-ray photoelectron spectroscopy (XPS). The results showed that MOFs functionalized with sulfur atom ligands have a built-in electric field that facilitates charge separation and migration. This study presents a new approach to enhance the piezoelectric properties of MOFs, which broadens their potential applications in piezo catalysis and piezo-photocatalysis. Additionally, it provides a sustainable method for reducing hexavalent chromium, contributing to the achievement of sustainable development goals, specifically SDG-6, SDG-7, SDG-9, and SDG-12.

4.
Int J Neural Syst ; 34(8): 2450042, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38818805

RESUMO

Timely and accurately seizure detection is of great importance for the diagnosis and treatment of epilepsy patients. Existing seizure detection models are often complex and time-consuming, highlighting the urgent need for lightweight seizure detection. Additionally, existing methods often neglect the key characteristic channels and spatial regions of electroencephalography (EEG) signals. To solve these issues, we propose a lightweight EEG-based seizure detection model named lightweight inverted residual attention network (LRAN). Specifically, we employ a four-stage inverted residual mobile block (iRMB) to effectively extract the hierarchical features from EEG. The convolutional block attention module (CBAM) is introduced to make the model focus on important feature channels and spatial information, thereby enhancing the discrimination of the learned features. Finally, convolution operations are used to capture local information and spatial relationships between features. We conduct intra-subject and inter-subject experiments on a publicly available dataset. Intra-subject experiments obtain 99.25% accuracy in segment-based detection and 0.36/h false detection rate (FDR) in event-based detection, respectively. Inter-subject experiments obtain 84.32% accuracy. Both sets of experiments maintain high classification accuracy with a low number of parameters, where the multiply accumulate operations (MACs) are 25.86[Formula: see text]M and the number of parameters is 0.57[Formula: see text]M.


Assuntos
Eletroencefalografia , Redes Neurais de Computação , Convulsões , Humanos , Eletroencefalografia/métodos , Convulsões/diagnóstico , Convulsões/fisiopatologia , Atenção/fisiologia , Processamento de Sinais Assistido por Computador
5.
Medicine (Baltimore) ; 103(15): e37522, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608108

RESUMO

BACKGROUND: Pain transcends simple physiology, encompassing biological, emotional, psychological, and social facets. Children show pronounced immediate and enduring responses to pain-related procedures. The aim of this meta-analysis is to investigate the efficacy and safety of the Buzzy device for needle-related procedures in children aged twelve years or younger. METHODS: PubMed, Web of Science, and Embase were searched from inception to July 2023. Only randomized controlled trials utilizing the Buzzy device for needle-related procedures in children under twelve years old were included. Two reviewers independently conducted study selection, data extraction, and risk of bias assessment. Random-effects models were utilized, and analyses were performed using mean differences or standardized mean differences as well as risk ratios. RESULTS: A total of 19 studies were included, involving 2846 participants (Buzzy = 1095, Control = 1751). Compared to no intervention, the Buzzy device significantly reduced pain response [self-report SMD = -1.90 (-2.45, -1.36), parental SMD = -3.04 (-4.09, -1.99), observer SMD = -2.88 (-3.75, -2.02)] and anxiety scores [self-report SMD = -1.97 (-3.05, -0.88), parental SMD = -2.01 (-2.93, -1.08), observer SMD = -1.92 (-2.64, -1.19)]. Compared to virtual reality (VR), the Buzzy device reduced self-reported anxiety levels SMD = -0.47 (-0.77, -0.17), and compared to distraction cards, the Buzzy device reduced parental and observer-reported pain [parental SMD = -0.85 (-1.22, -0.48), observer SMD = -0.70 (-1.00, -0.40)] and anxiety [parental SMD = -0.96 (-1.46, -0.47), observer SMD = -0.91 (-1.40, -0.42)]. Subgroup analysis results showed that procedure type, patient age, measurement scales used, and distance of operation were not the reason of heterogeneity. The summarized first puncture attempt success rate did not differ from other interventions. There were no significant adverse events in the included studies. CONCLUSION: The Buzzy device reduces pain and anxiety in children during needle procedures, ensuring success and safety. Additionally, the effectiveness of the Buzzy device in reducing pain during venipuncture is superior when compared to its effectiveness during intramuscular injections.


Assuntos
Agulhas , Humanos , Criança , Agulhas/efeitos adversos , Pré-Escolar , Ensaios Clínicos Controlados Aleatórios como Assunto , Manejo da Dor/métodos , Manejo da Dor/instrumentação , Dor Processual/prevenção & controle , Dor Processual/etiologia , Medição da Dor , Ansiedade/prevenção & controle , Lactente
6.
BMC Genomics ; 25(1): 320, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549066

RESUMO

BACKGROUND: Stigma exsertion is an essential agricultural trait that can promote cross-pollination to improve hybrid seed production efficiency. However, the molecular mechanism controlling stigma exsertion remains unknown. RESULTS: In this study, the Nicotiana tabacum cv. K326 and its two homonuclear-heteroplasmic lines, MSK326 (male-sterile) and MSK326SE (male-sterile and stigma exserted), were used to investigate the mechanism of tobacco stigma exsertion. A comparison of the flowers between the three lines showed that the stigma exsertion of MSK326SE was mainly due to corolla shortening. Therefore, the corollas of the three lines were sampled and presented for RNA-seq analysis, which found 338 candidate genes that may cause corolla shortening. These genes were equally expressed in K326 and MSK326, but differentially expressed in MSK326SE. Among these 338 genes, 15 were involved in hormone synthesis or signal transduction pathways. Consistently, the content of auxin, dihydrozeatin, gibberellin, and jasmonic acid was significantly decreased in the MSK326SE corolla, whereas abscisic acid levels were significantly increased. Additionally, seven genes involved in cell division, cell cycle, or cell expansion were identified. Protein-protein interaction network analysis identified 45 nodes and 79 protein interactions, and the largest module contained 20 nodes and 52 protein interactions, mainly involved in the hormone signal transduction and pathogen defensive pathways. Furthermore, a putative hub gene coding a serine/threonine-protein kinase was identified for the network. CONCLUSIONS: Our results suggest that hormones may play a key role in regulating tobacco stigma exsertion induced by corolla shortening.


Assuntos
Nicotiana , Transcriptoma , Nicotiana/genética , Revelação , Ácidos Indolacéticos/metabolismo , Hormônios/metabolismo , Flores/metabolismo
7.
Angew Chem Int Ed Engl ; 63(18): e202401331, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38456641

RESUMO

A general approach to constructing room temperature phosphorescence (RTP) materials involves the incorporation of a phosphorescent emitter into a rigid host or polymers with high glass transition temperature. However, these materials often suffer from poor processability and suboptimal mechanical properties, limiting their practical applications. In this work, we developed benzothiadiazole-based dialkene (BTD-HEA), a multifunctional phosphorescent emitter with a remarkable yield of intersystem crossing (ΦISC, 99.83 %). Its high triplet exciton generation ability and dialkene structure enable BTD-HEA to act as a photoinitiator and crosslinker, efficiently initiating the polymerization of various monomers within 120 seconds. A range of flexible phosphorescence gels, including hydrogels, organogels, ionogels, and aerogels were fabricated, which exhibit outstanding stretchability and recoverability. Furthermore, the unique fluorescent-phosphorescent colorimetric properties of the gels provide a more sensitive method for the visual determination of the polymerization process. Notably, the phosphorescent emission intensity of the hydrogel can be increased by the formation of ice, allowing for the precise detection of hydrogel freezing. The versatility of this emitter paves the way for fabricating various flexible phosphorescence gels with diverse morphologies using microfluidics, film-shearing, roll coating process, and two/three-dimensional printing, showcasing its potential applications in the fields of bioimaging and bioengineering.

8.
Polymers (Basel) ; 16(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38399900

RESUMO

Ultrafine, highly active coal gasification slag (HCGS) was produced via a sustainable, green dry-ball-milling method. Coal gasification fine slag (CGS), a potential environmental pollutant, was used as a new source of rubber filler without pre-treatment, enabling waste utilisation. HCGS was added to styrene-butadiene rubber (ESBR) composites, and the effects of HCGS and the filler content on the mechanical and thermal stabilities of SBR were evaluated. The procedure conforms to important green metrics, requiring no solvent or additional reagent, or solvent-assistance for product collection. HCGS reduced the scorch time (t10) and curing time (t90) of the filled ESBR composites relative to those of pure SBR and improved the mechanical parameters. The tensile strength at 50 phr reached 10.91 MPa, and the tear strength at 90 phr reached 64.92 kN/m, corresponding to 9.4- and 3.92-fold increases relative to that of SBR filled with HCGS, respectively. HCGS exerted a reinforcing effect on ESBR, comparable to that of commercial carbon black (CB) N330. HCGS improves the binding between rubber molecules and filler particles and captures the rubber chain, thereby limiting its movement. HCGS is potentially applicable as a CB substitute in the rubber industry, with environmental and economic benefits in the disposal of CGS.

9.
Int J Biol Macromol ; 263(Pt 1): 130355, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395281

RESUMO

The hematopoietic function of a polysaccharide derived from Russula griseocarnosa was demonstrated in K562 cells, and subsequently purified through chromatography to obtain RGP1. RGP1 is a galactan composed of 1,6-α-D-Galp as the main chain, with partial substitutions. A -CH3 substitution was detected at O-3 of 1,6-α-D-Galp. The possible branches at O-2 of 1,6-α-D-Galp was α-L-Fucp. In mice with cyclophosphamide (CTX)-induced hematopoietic dysfunction, RGP1 alleviated bone marrow damage and multinucleated giant cell infiltration of the spleen, increased the number of long-term hematopoietic stem cells, and regulated the levels of myeloid cells in the peripheral blood. Furthermore, RGP1 promoted the differentiation of activated T cells and CD4+ T cells without affecting natural killer cells and B cells. Proteomic analysis, detection of cytokines, and western blotting revealed that RGP1 could alleviate hematopoietic dysfunction by promoting the activation of CD4+ T cells and the Janus kinase/ signal transducer and activator of transcription 3 pathway. The present study provides experimental evidence to support the application of RGP1 in CTX-induced hematopoietic dysfunction.


Assuntos
Basidiomycota , Proteômica , Animais , Camundongos , Ciclofosfamida/farmacologia , Polissacarídeos/farmacologia
10.
Nat Commun ; 15(1): 1269, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341441

RESUMO

A strategy is pioneered for achieving high-temperature phosphorescence using planar rigid molecules as guests and rigid polymers as host matrix. The planar rigid configuration can resist the thermal vibration of the guest at high temperatures, and the rigidity of the matrix further enhances the high-temperature resistance of the guest. The doped materials exhibit an afterglow of 40 s at 293 K, 20 s at 373 K, 6 s at 413 K, and a 1 s afterglow at 433 K. The experimental results indicate that as the rotational ability of the groups connected to the guests gradually increases, the high-temperature phosphorescence performance of the doped materials gradually decreases. In addition, utilizing the property of doped materials that can emit phosphorescence at high temperatures and in high smoke, the attempt is made to use organic phosphorescence materials to identify rescue workers and trapped personnel in fires.

11.
Int J Biol Macromol ; 261(Pt 1): 129715, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38281519

RESUMO

In mammals, epigenetic modifications involving DNA methylation are necessary for the completion of the cell differentiation process. However, the global DNA methylation landscape and its dynamics during yak adipocyte differentiation remain unexplored. Here, we performed whole-genome bisulfite sequencing (WGBS) to asses DNA methylation in yak preadipocytes and adipocytes, combining these results with those of our previous studies on changes in chromatin accessibility and gene expression during yak adipogenesis. The results showed that CG methylation levels were lower in promoter than in exon and intron, and gradually decreasing from the distal regions to transcription start site (TSS). There was a significant negative correlation between CG methylation levels located in promoter and gene expression levels. The 46 genes shared by CG differentially methylated regions (DMRs) and differential chromatin accessibility were significantly enriched in Hedgehog and PI3K-Akt signaling pathways. ATAC-seq peaks with high chromatin accessibility located in both promoter (≤ 2 kb from TSS) and distal (> 2 kb from TSS) regions corresponded to low methylation levels. Taken together, these findings demonstrated that DNA methylation and its interactions with chromatin accessibility regulate gene expression during yak adipocyte differentiation, contributing to the understanding of mechanisms of various epigenetic modifications and their interactions in adipogenesis.


Assuntos
Metilação de DNA , Fosfatidilinositol 3-Quinases , Animais , Bovinos , Metilação de DNA/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Diferenciação Celular/genética , Cromatina/genética , Cromatina/metabolismo , Adipócitos , Mamíferos/genética
12.
Oral Dis ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225738

RESUMO

OBJECTIVES: Tumor-associated neutrophils (TANs) are among the most abundant inflammatory cells in tumor microenvironment (TME). Aldehyde dehydrogenase 3A1 (ALDH3A1) is significantly reduced in oral squamous cell carcinoma (OSCC), ALDH3A1 overexpression suppresses tumorigenesis by inhibiting inflammation. This study investigated the relationship and mechanisms underlying the crosstalk between ALDH3A1 and TANs in OSCC. MATERIALS AND METHODS: Immunohistochemistry and immunofluorescence were performed to investigate the abundance of TANs and the expression of ALDH3A1. dHL-60 were induced with tumor-conditioned media and recombinant IL-6/IL-8. The expression of key proteins in PI3K/AKT/NF-κB pathway were detected by RT-PCR and western blot. A xenograft model was utilized to examine the effect of ALDH3A1 on tumorigenicity and polarization of TANs. RESULTS: In patients with OSCC, TANs significantly increased and were associated with a worse prognosis. Additionally, ALDH3A1 negatively correlated with TANs infiltration and especially the N2 phenotype which was the prominent part in OSCC. Furthermore, our study demonstrated that tumor-derived IL-8 drives ALDH3A1-mediated TANs N2 polarization in the TME through PI3K/AKT/NF-κB pathway in vitro and in vivo. CONCLUSION: Our results indicate that TANs can serve as a prognostic biomarker and ALDH3A1 could be a promising therapeutic target for regulating TANs N2 polarization in antitumor therapy.

13.
Int J Biol Macromol ; 258(Pt 1): 128819, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104691

RESUMO

The water-soluble neutral polysaccharide BEP2, with a molecular weight of 26.65 kDa, was isolated from the aqueous extract obtained from the fruiting bodies of Boletus aereus Bull. BEP2 primarily comprises Gal, with specific site substitutions speculated at partial positions, such as the substitution of -OCH3 at position H-3 or the branch at position C-2 including α-L-Fucp-(1→, α-D-Manp-(1 â†’ and α-D-Manp-(1 â†’ 3)-α-L-Fucp-(1 â†’ 6)-ß-D-Glcp-(1→. Treatment with BEP2 significantly enhanced learning, memory, and cognitive function, while concurrently reducing the accumulation of ß-amyloid and suppressing neuroinflammation within the brains of APP/PS1 mice. Based on the results of biochemical detection, gut microbiota analysis, and metabolomic profiling, we found that BEP2 significantly upregulated the abundance of two bacterial families while downregulation that of seven bacterial families within the intestinal ecosystem. Notably, the abundance of the S24-7 family was significantly increased. Treatment with BEP2 upregulated five metabolites, while downregulating three metabolites, including norepinephrine. Additionally, BEP2 decreased the levels of interleukin (IL)-1ß and IL-6, regulated the activities of microglial cells and astrocytes and increased the levels of the chemokine fractalkine (CX3CL1) and its receptor on microglia (CX3CR1), as well as that of transforming growth factor (TGF)-ß1. These findings confirmed the suppressive effects of BEP2 on neuroinflammation.


Assuntos
Doença de Alzheimer , Basidiomycota , Humanos , Camundongos , Animais , Doença de Alzheimer/metabolismo , Camundongos Transgênicos , Doenças Neuroinflamatórias , Ecossistema , Peptídeos beta-Amiloides/metabolismo , Modelos Animais de Doenças
14.
Nanotechnology ; 35(16)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38150735

RESUMO

ß-Ga2O3has been widely investigated for its stability and thermochemical properties. However, the preparation ofß-Ga2O3thin films requires complex growth techniques and high growth temperatures, and this has hindered the application ofß-Ga2O3thin films. In this study,ß-Ga2O3thin films with good crystalline quality were prepared using a green method, and an ultraviolet (UV) detector based onß-Ga2O3with a photocurrent of 2.54 × 10-6A and a dark current of 1.19 × 10-8A has been developed. Two-dimensional materials have become premium materials for applications in optoelectronic devices due to their high conductivity. Here, we use the suitable energy band structure between Nb2C and Ga2O3to create a high carrier migration barrier, which reduces the dark current of the device by an order of magnitude. In addition, the device exhibits solar-blind detection, high responsiveness (28 A W-1) and good stability. Thus, the Nb2C/ß-Ga2O3heterojunction is expected to be one of the promising devices in the field of UV photoelectric detection.

15.
Biosci. j. (Online) ; 30(2): 320-325, mar./apr. 2014. tab
Artigo em Inglês | LILACS | ID: biblio-947031

RESUMO

With the world's focus on bio-fuel, cellulolytic microorganisms are being exclusively explored. In this paper, a strain of rod, NBG, was obtained from the rumen of Inner Mongolia sheep by an enrichment method with Whatman No.1 filter paper as the selective substrate. The strain was found to effectively degrade filter paper in solution. It was identified as Fibrobacter succinogenes based on DNA G + C mol %, together with morphological, physiological and biochemical tests. The endo-glucanase, -glucosidase and filter paper enzyme activity of NBG reached 62.5 ± 3.0 U•mL-1, 169.0 ± 9.4 U•mL-1 and 30.8 ± 5.4 U•mL-1, respectively, within 72 h of fermentation.


Com o foco mundial em biocombustíveis, microrganismos celuloliticos estão sendo exclusivamente explorados. Neste trabalho, uma cepa de bastão, NBG foi obtida do rumen de ovelhas do interior DA Mongolia com o método de enriquecimento e o papel de filtro No.1 como substrato seletivo. A cepa foi encontrada para degradar efetivamente o papel de filtro na solução. Foi identificado como Fibrobacter succinogenes baseado em DNA + c mol% juntamente com testes morofológicos, fisiológico e bioquímicos. A endo-glucanase e o papel de filtro chegaram com relação a atividade de enzima NBG 62.5 ± 3.0 U.ml-1, 169±9.4U.ml-1 e 30.8±5.4U.ml-1, respectivamente, com 72 horas de fermentação.


Assuntos
Ruminantes , Fibrobacter , Biocombustíveis
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