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Chromatin accessibility plays a critical role in the regulation of cell fate decisions. Although gene expression changes have been extensively profiled at the single-cell level during early embryogenesis, the dynamics of chromatin accessibility at cis-regulatory elements remain poorly studied. Here, we used a plate-based single-cell ATAC-seq method to profile the chromatin accessibility dynamics of over 10 000 nuclei from zebrafish embryos. We investigated several important time points immediately after zygotic genome activation (ZGA), covering key developmental stages up to dome. The results revealed key chromatin signatures in the first cell fate specifications when cells start to differentiate into enveloping layer (EVL) and yolk syncytial layer (YSL) cells. Finally, we uncovered many potential cell-type specific enhancers and transcription factor motifs that are important for the cell fate specifications.
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Cromatina , Desenvolvimento Embrionário , Peixe-Zebra , Animais , Cromatina/genética , Cromatina/metabolismo , Gema de Ovo/metabolismo , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Análise de Célula Única , Domínios e Motivos de Interação entre Proteínas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
The activity of Ru-based alkaline hydrogen oxidation reaction (HOR) electrocatalysts usually decreases rapidly at potentials higher than 0.1 V (vs a reversible hydrogen electrode (RHE)), which significantly limits the lifetime of fuel cells. It is found that this phenomenon is caused by the overadsorption of the O species due to the overcharging of Ru nanoparticles at high potentials. Here, Mn1Ox(OH)y clusters-modified Ru nanoparticles (Mn1Ox(OH)y@Ru/C) were prepared to promote charge transfer from overcharged Ru nanoparticles to Mn1Ox(OH)y clusters. Mn1Ox(OH)y@Ru/C exhibits high HOR activity and stability over a wide potential range of 0-1.0 V. Moreover, a hydroxide exchange membrane fuel cell with a Mn1Ox(OH)y@Ru/C anode delivers a high peak power density of 1.731 W cm-2, much superior to that of a Pt/C anode. In situ X-ray absorption fine structure (XAFS) analysis and density functional theory (DFT) calculations reveal that Mn in Mn1Ox(OH)y clusters could receive more electrons from overcharged Ru at higher potentials and significantly decrease the overadsorption of the O species on Ru, thus permitting the HOR on Ru to proceed at high potentials. This study provides guidance for the design of alkaline HOR catalysts without activity decay at high potentials.
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Developing low-loading platinum-group-metal (PGM) catalysts is one of the key challenges in commercializing anion-exchange-membrane-fuel-cells (AEMFCs), especially for hydrogen oxidation reaction (HOR). Here, ruthenium-iridium nanoparticles being deposited on a Zn-N species-doped carbon carrier (Ru6Ir/Zn-N-C) are synthesized and used as an anodic catalyst for AEMFCs. Ru6Ir/Zn-N-C shows extremely high mass activity (5.87 A mgPGM -1) and exchange current density (0.92 mA cm-2), which is 15.1 and 3.9 times that of commercial Pt/C, respectively. Based on the Ru6Ir/Zn-N-C AEMFCs achieve a peak power density of 1.50 W cm-2, surpassing the state-of-the-art commercial PtRu catalysts and the power ratio of the normalized loading is 14.01 W mgPGM anode -1 or 5.89 W mgPGM -1 after decreasing the anode loading (87.49 µg cm-2) or the total PGM loading (0.111 mg cm-2), satisfying the US Department of Energy's PGM loading target. Moreover, the solvent and solute isotope separation method is used for the first time to reveal the kinetic process of HOR, which shows the reaction is influenced by the adsorption of H2O and OH-. The improvement of the hydrogen bond network connectivity of the electric double layer by adjusting the interfacial H2O structure together with the optimized HBE and OHBE is proposed to be responsible for the high HOR activity of Ru6Ir/Zn-N-C.
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The development of chemo-resistance in nasopharyngeal carcinoma (NPC) presents a significant therapeutic challenge, and its underlying mechanisms remain poorly understood. In our previous studies, we highlighted the association between isoprenylcysteine carboxylmethyltransferase (ICMT) and chemoresistance in NPC. In this current research, we revealed that both 5-FU and cisplatin-resistant NPC cells exhibited elevated mitochondrial function and increased expression of mitochondrial genes, independent of ICMT. Our investigations further showed that classic mitochondrial inhibitors, such as oligomycin, antimycin, and rotenone, were notably more effective in reducing viability in chemo-resistant NPC cells compared to parental cells. Moreover, we identified two antimicrobial drugs, tigecycline and atovaquone, recognized as mitochondrial inhibitors, as potent agents for decreasing chemo-resistant NPC cells by targeting mitochondrial respiration. Remarkably, tigecycline and atovaquone, administered at tolerable doses, inhibited chemo-resistant NPC growth in mouse models and extended overall survival rates. This work unveils the efficacy of mitochondrial inhibition as a promising strategy to overcome chemo-resistance in NPC. Additionally, our findings highlight the potential repurposing of clinically available drugs like tigecycline and atovaquone for treating NPC patients who develop chemoresistance.
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Resistencia a Medicamentos Antineoplásicos , Neoplasias Nasofaríngeas , Animais , Camundongos , Humanos , Carcinoma Nasofaríngeo/metabolismo , Atovaquona/farmacologia , Atovaquona/uso terapêutico , Tigeciclina/farmacologia , Tigeciclina/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/farmacologia , Mitocôndrias , Neoplasias Nasofaríngeas/metabolismoRESUMO
OBJECTIVE: With the evolution of data algorithms and personalized push systems in mobile applications, patients who have searched for disease-related information may repeatedly receive similar content on app homepages or through notifications. This study aims to assess the influence of health-related content delivered through mobile applications on the anxiety and depression levels of caregivers of pediatric oncology patients. METHODS: A survey consisting of 16 questions was conducted among 91 caregivers of pediatric oncology patients at the Children's Hospital affiliated with Chongqing Medical University. The questionnaire was designed by oncologists and the Hospital Anxiety and Depression Scale was used to assess the caregivers' psychological states. RESULTS: The study found that 31.5% of caregivers exhibited borderline anxiety symptoms, while 20.2% displayed borderline depression symptoms. Caregivers who noticed changes in homepage recommendations reported higher levels of anxiety (p = .004) and depression (p = .034). Additionally, 50.6% occasionally felt anxious or uneasy due to personalized notifications and 19.1% frequently felt this way. Moreover, 53.9% of the caregivers reported a negative impact on their emotions or daily life. SIGNIFICANCE: Personalized push notifications related to disease information in mobile applications can impose a significant psychological burden on patients and their caregivers. Mobile application developers and healthcare providers must strengthen their support in the digital health domain to enhance the emotional well-being of cancer patients and their caregivers.
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Ansiedade , Cuidadores , Aplicativos Móveis , Neoplasias , Humanos , Cuidadores/psicologia , Feminino , Masculino , Criança , Neoplasias/psicologia , Neoplasias/enfermagem , Neoplasias/terapia , Adulto , Ansiedade/etiologia , Inquéritos e Questionários , Depressão/etiologia , Adolescente , Pré-Escolar , Pessoa de Meia-Idade , SeguimentosRESUMO
This study focuses on the diffusion patterns of principal ore-forming elements (Pb and Zn) and associated elements (Cd, Cu, Cr, and As) in lead-zinc ore. Sampling points in upwind and downwind directions of lead-zinc ore areas at various densities (1 N/km2 - 4 N/km2) were categorized. This study analyzed the statistical relationship between the content of PTEs in the soil around lead-zinc ore and the source strength and dominant wind direction, constructed one-dimensional and two-dimensional diffusion model, and simulated the EER scope caused by PTEs. The findings indicate that: (1) concerning source strength, the content of PTEs in soils of high-density ore aggregation areas is significantly higher than in low-density ore aggregation areas. However, the impact of source strength decreases with decreasing ore grade, with a difference in Pb content of 1.71 times among principal ore-forming elements and almost consistent Cd content among associated elements. (2) Regarding the transport pathways, for most PTEs, the inverse proportion coefficients downwind are higher than upwind, approximately 1.18-3.63 times, indicating greater migration distances of PTEs downwind due to atmospheric dispersion. (3) By establishing a two-dimensional risk diffusion model, the study simulates the maximum radius of risk diffusion (r = 5.7 km), the 50% probability radius (r = 3.1 km), and the minimum radius (r = 0.8 km) based on the maximum, median, and minimum values statistically obtained from the EER. This study provides a scientific basis for implementing preventive measures for PTEs accumulation in soil within different pollution ranges. Different risk prevention and control measures should be adopted for PTEs accumulation in soil within the three ranges after cutting off pollution sources. Subsequent research should further investigate the impact and contribution of atmospheric transmission and surface runoff on the diffusion of PTEs in areas with high risk near lead-zinc ore.
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Monitoramento Ambiental , Mineração , Poluentes do Solo , Poluentes do Solo/análise , Difusão , Solo/química , Chumbo/análise , Modelos Teóricos , Vento , Zinco/análiseRESUMO
Artificial forest restoration is widely recognized as a crucial approach to enhance the potential of soil carbon sequestration. Nevertheless, there is still limited understanding regarding the dynamics of aggregate organic carbon (OC) and the underlying mechanisms driving these dynamics after artificial forest restoration. To address this gap, we studied Pinus tabuliformis forests and adjacent farmland in three recovery periods (13, 24 and 33 years) in the Loess Plateau region. Samples of undisturbed soil from the surface layer were collected and divided into three aggregate sizes: >2 mm (large aggregate), 0.25-2 mm (medium aggregate), and <0.25 mm (small aggregate). The aim was to examine the distribution of OC and changes in enzyme activity within each aggregate size. The findings revealed a significant increase in OC content for all aggregate sizes following the restoration of Pinus tabuliformis forests. After 33 years of recovery, the OC of large aggregates, medium aggregates and micro-aggregates increased by (30.23 ± 9.85)%, (36.71 ± 21.60)% and (37.88 ± 16.07)% respectively compared with that of farmland. Moreover, the restoration of Pinus tabuliformis forests lead to increased activity of hydrolytic enzymes and decreased activity of oxidative enzymes. It is noteworthy that the regulation of carbon in all aggregates is influenced by soil P-limitation. In large aggregates, P-limitation promotes the enhancement of hydrolytic enzyme activity, thereby facilitate OC accumulation. Conversely, in medium and small aggregates, P-limitation inhibits the increase in oxidative enzyme activity, resulting in OC accumulation. The results emphasize the importance of P-limitation in regulating OC accumulation during the restoration of Pinus tabulaeformis forest, in which large aggregates play a leading role.
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Carbono , Florestas , Pinus , Solo , Solo/química , Carbono/análise , Carbono/metabolismo , Sequestro de Carbono , ChinaRESUMO
Atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts have exhibited encouraging oxygen reduction reaction (ORR) activity. Nevertheless, the insufficient long-term stability remains a widespread concern owing to the inevitable 2-electron byproducts, H2O2. Here, we construct Co-N-Cr cross-interfacial electron bridges (CIEBs) via the interfacial electronic coupling between Cr2O3 and Co-N-C, breaking the activity-stability trade-off. The partially occupied Cr 3d-orbitals of Co-N-Cr CIEBs induce the electron rearrangement of CoN4 sites, lowering the Co-OOH* antibonding orbital occupancy and accelerating the adsorption of intermediates. Consequently, the Co-N-Cr CIEBs suppress the two-electron ORR process and approach the apex of Sabatier volcano plot for four-electron pathway simultaneously. As a proof-of-concept, the Co-N-Cr CIEBs is synthesized by the molten salt template method, exhibiting dominant 4-electron selectively and extremely low H2O2 yield confirmed by Damjanovic kinetic analysis. The Co-N-Cr CIEBs demonstrates impressive bifunctional oxygen catalytic activity (âµE=0.70â V) and breakthrough durability including 100 % current retention after 10â h continuous operation and cycling performance over 1500â h for Zn-air battery. The hybrid interfacial configuration and the understanding of the electronic coupling mechanism reported here could shed new light on the design of superdurable M-N-C catalysts.
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The main group metals are commonly perceived as catalytically inert in the context of oxygen reduction reactions (ORR) due to the delocalized valence orbitals. Regulating the local environment and structure of metal center coordinated by nitrogen ligands (M-Nx) is a promising approach to accelerate catalytic dynamics. Herein, we, for the first time, report the atomically dispersed Al catalysts coordinated with N and C atoms for 4-electron ORR. The axial coordinated pyrrolyl N group (No) is constructed in the Al-N4-No moiety to regulate the p-band structure of Al center, effectively steering the local environment and structure of the square planar Al-N4 sites, which typically exhibit too strong interaction with ORR intermediates. The dynamic covalency competition of axial Al-No and Al-O bonding could endow the Al center with moderate hybridization between Al 3p orbital and O 2p orbital, alleviating the binding energy of ORR intermediates. The as-prepared Al-N4-No electrocatalyst exhibits excellent ORR activity, selectivity, and durability, along with the rapid kinetics as demonstrated by in situ Raman spectroscopy. This work offers a fundamental comprehension of the fine regulation on p-band and guides the rational design of main-group metal-based single atom catalysts.
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Climate change poses an urgent threat, necessitating the implementation of measures to actively reduce carbon emissions. The development of effective carbon emission reduction policies requires accurate estimation of the costs involved. In situations where actual prices of commodities are not available in the market, shadow pricing provides a useful method to calculate relative prices between commodities with and without price information. However, most studies focus on the industry, with few contributions on agricultural sector. This paper estimates the shadow price of carbon emissions in the agricultural sector from a provincial perspective, incorporating the impact of livestock into the calculation of carbon emissions and shadow pricing. Our findings indicate that ignoring livestock may overestimate CSP values. On the whole, the level of carbon shadow price is rising, indicating good green development in China's agricultural sector. The two types of convergence results show that there is sigma convergence and beta convergence in the western and central regions, demonstrating a significant improvement in environmental performance.
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Carbono , Indústrias , Carbono/análise , Custos e Análise de Custo , Dióxido de Carbono/análise , Agricultura , China , Desenvolvimento EconômicoRESUMO
The use of waste polyethylene (WPE) in modified asphalt is frequently employed to reduce environmental pollution and improve asphalt properties. However, research has shown that using WPE alone as a modifier does not effectively enhance the low-temperature flexibility of asphalt. This study aims to investigate the potential of utilizing WPE and waste cooking oil (WCO) as composite modifiers to enhance the properties of virgin asphalt under both high and low-temperature conditions. The contents of WPE and WCO were used, and the preparation process for the modified asphalt was optimized through an orthogonal experiment. The experimental results indicate that the optimal formulation for the WPE/WCO composite modified asphalt (WPE/WCO-A) is obtained with an additive dosage of 8% and 1% by mass of virgin asphalt for WPE and WCO, respectively, as well as the maintenance process at a temperature of 140 °C and a duration of 2 h. Dynamic shear rheometer (DSR) results reveal that WPE/WCO composite modifier can greatly improve the high-temperature deformation resistance of asphalt. Bending beam rheometer (BBR) tests confirm that WPE adversely affects the low-temperature flexibility of asphalt, while the addition of WCO can improve it. WPE/WCO-A has even better low-temperature properties than virgin asphalt (VA). The Fourier transform infrared spectroscopy (FT-IR) results suggest that the composite modification of asphalt by WPE/WCO modifiers is dominated by physical action. Furthermore, the fluorescence microscopy test results demonstrate that WCO can promote WPE swelling in asphalt. This study offers a novel approach to improve the comprehensive properties of asphalt through composite modification using WPE and WCO.
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Hidrocarbonetos , Polietileno , Polietileno/química , Hidrocarbonetos/químicaRESUMO
The existing methodologies for allocating highway safety improvement funding closely rely on the utilization of crash prediction models. Specifically, these models produce predictions that estimate future crash hazard levels in different geographical areas, which subsequently support the future funding allocation strategies. In recent years, there is a burgeoning interest in applying artificial intelligence (AI)-based models to perform crash prediction tasks. Despite the remarkable accuracy of these AI-based crash prediction models, they have been observed to yield biased prediction outcomes across areas of different socioeconomic statuses. These biases are primarily attributed to the inherent measurement and representation biases of AI-based prediction models. More precisely, measurement bias arises from the selection of target variables to reflect crash hazard levels, while representation bias results from the issue of imbalanced number of samples representing areas with different socioeconomic statuses within the dataset. Consequently, these biased prediction outcomes have the potential to perpetuate an unfair allocation of funding resources, contributing to worsen social inequality over time. Drawing upon a real-world case study in North Carolina, this study designs an AI-based crash prediction model that utilizes previous sociodemographic and crash-related variables to predict future severe crash rate of each area to reflect the crash hazardous level. By incorporating a fair regression framework, this study endeavors to transform the crash prediction model to become both fair and accurate, aiming to support equitable and responsible safety improvement funding allocation strategies.
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Acidentes de Trânsito , Inteligência Artificial , Humanos , Acidentes de Trânsito/prevenção & controle , Acidentes de Trânsito/estatística & dados numéricos , Inteligência Artificial/economia , Viés , Alocação de Recursos , Modelos Estatísticos , Fatores Socioeconômicos , SegurançaRESUMO
In this work, an efficient utilization method for red mud (RM) is provided through recycling RM as a mineral admixture for the preparation of foamed concrete (FC). Specifically, FC with different RM contents was prepared and investigated in terms of workability, mechanical properties, and hydration products. Results show that adding RM can significantly shorten the setting time, while it inevitably weakens the mechanical properties and fluidity of FC. However, the compressive strength of FC can still meet the strength predicted by the specification requirements when the RM replaces cement with 60% content (3d > 1.6 MPa). Most importantly, the heavy metals leaching from RM-based FC under the action of rain is still unclear, so a device for simulating stormwater runoff was designed to test the heavy metal leaching risk of RM-based FC. The findings indicate that the solidification of cement and the high basicity of the matrix can effectively reduce the leaching risk of heavy metals from RM in FC. Although the pore structure analysis demonstrates that the porosity and connected pores of FC will be deteriorated as RM concentration increases. The results are of great significance for the recycling of waste and the sustainable development of building materials.
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Materiais de Construção , Metais Pesados , Metais Pesados/química , Reciclagem , PorosidadeRESUMO
The Bifidobacterium bifidum SAM-VI riboswitch undergoes dynamic conformational changes that modulate downstream gene expression. Traditional structural methods such as crystallography capture the bound conformation at high resolution, and additional efforts would reveal details from the dynamic transition. Here, we revealed a transcription-dependent conformation model for Bifidobacterium bifidum SAM-VI riboswitch. In this study, we combine small-angle X-ray scattering, chemical probing, and isothermal titration calorimetry to unveil the ligand-binding properties and conformational changes of the Bifidobacterium bifidum SAM-VI riboswitch and its variants. Our results suggest that the SAM-VI riboswitch contains a pre-organized ligand-binding pocket and stabilizes into the bound conformation upon binding to SAM. Whether the P1 stem formed and variations in length critically influence the conformational dynamics of the SAM-VI riboswitch. Our study provides the basis for artificially engineering the riboswitch by manipulating its peripheral sequences without modifying the SAM-binding core.
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Bifidobacterium bifidum , Conformação de Ácido Nucleico , Riboswitch , Bifidobacterium bifidum/metabolismo , Bifidobacterium bifidum/genética , S-Adenosilmetionina/metabolismo , S-Adenosilmetionina/química , Espalhamento a Baixo Ângulo , Ligantes , RNA Bacteriano/química , RNA Bacteriano/metabolismo , RNA Bacteriano/genética , Sítios de LigaçãoRESUMO
Biodegradation effectiveness of S. maltophilia DHHJ is determined by its ability to attach to the hydrolyzed feather keratin monomers. This binding capacity can be influenced by many components in the culture medium. Keratin monomers from feathers or those produced by gene overexpression can induce keratinase production in S. maltophilia DHHJ, and several proteases lack the ability to degrade keratin fragments and cysteines. In this study, we co-incubated FITC-labelled keratin monomers with S. maltophilia DHHJ cells in the presence of BSA, DNA, ATP, and several metal ions, and measured fluorescence values and keratinase activity. BSA was found to compete with keratins for cell binding sites, resulting in less keratinase production. DNA did not interfere with cellular binding to keratins revealing unchanged keratinase level. ATP, along with metal ions, enhanced the cellular binding capacity to keratins and increased the production of keratinase by S. maltophilia DHHJ. Fragments of keratin monomers degraded by proteases reduced the ability of cells to bind to keratin and affected enzyme production. Cysteine, a characteristic amino acid of feather keratin, did not have an effect on cellular binding to keratin monomer or on keratinase production. This study will facilitate the tweaking of catalytic parameters to improve feather biodegradation by S. maltophilia DHHJ.
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OBJECTIVES: This study aims to investigate the primary target and potential mechanism of mangiferin (MF) in treating oral submucous fibrosis (OSF) through Gene Expression Omnibus (GEO) database chip mining, network pharmacology, and molecular docking techniques. METHODS: Potential therapeutic targets for OSF were identified using GEO chip data. The potential targets of MF were predicted, and disease-related targets for OSF were collected from databases. A Venn diagram was created using the EVenn platform to identify overlapping targets. The protein-protein interaction (PPI) network was constructed using the STRING database. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using the DAVID platform. Cytoscape 3.10.1 software was used to visualize a drug-target-pathway-disease network, while AutoDocktools 1.5.6 software was employed for molecular docking analysis. RESULTS: A total of 356 potential targets for MF and 360 disease-related targets for OSF were obtained from multiple databases. The top 15 key target proteins in the PPI network were selected as significant candidates. GO function and KEGG pathway enrichment analyses revealed that MF treatment primarily involved advanced glycation end products-receptor (AGE-RAGE), epidermal growth factor receptor (EGFR), and other signaling pathways associated with OSF pathogenesis. Molecular docking analysis demonstrated that MF exhibited a strong binding activity toward AKT serine kinase 1 (AKT1), tumor necrosis factor (TNF), and other core targets. CONCLUSIONS: These findings suggest that MF may exert its therapeutic effects on OSF through a multitarget approach involving various signaling pathways.
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Simulação de Acoplamento Molecular , Farmacologia em Rede , Fibrose Oral Submucosa , Mapas de Interação de Proteínas , Xantonas , Xantonas/uso terapêutico , Xantonas/farmacologia , Fibrose Oral Submucosa/tratamento farmacológico , Fibrose Oral Submucosa/metabolismo , Humanos , Ontologia Genética , Mineração de Dados , Receptores ErbB/metabolismo , Software , Transdução de SinaisRESUMO
This study combined process simulation and actual measurement to construct a multipath diffusion and spatial accumulation model of Cd in a typical lead-zinc mining area through accuracy and root mean square error(RMSE) analysis. The results indicated that (1) the diffusion of Cd was in a quadratic inverse proportional relationship with the distance from the pollution source within watershed. The average annual atmospheric Cd sedimentation in study area was 0.71 * 10-6 g and the contribution of runoff diffusion to Cd exceeded 80%. (2) With the increase in the concentration range of Cd content (k) carried by unit runoff sediment, the model accuracy and RMSE showed decreasing trends. However, when the lower and upper limits of k were 10% and 90%, the model accuracy reached 75%. (3) Two sub-watersheds with same dominant wind direction but different runoff directions were selected to verify the model accuracy, indicating that the model construction method can precisely simulate the spatial accumulation of Cd in similar mining areas. The results provide a scientific basis for the prevention of heavy metal diffusion in lead-zinc mines. Future research should focus on the migration pathways of heavy metals through vertical infiltration caused by rainfall to further optimise the model structure and accuracy.
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INTRODUCTION: The global poultry industry produces millions of tons of waste feathers every year, which can be bio-degraded to make feed, fertilizer, and daily chemicals. However, feather bio-degradation is a complex process that is not yet fully understood. This results in low degradation efficiency and difficulty in industrial applications. Omics-driven system biology research offers an effective solution to quickly and comprehensively understand the molecularmechanisms involved in a metabolic pathway. METHODS: In the early stage of this process, feathers are hydrolyzed into water-soluble keratin monomers. In this study, we used high-throughput RNA-seq technology to analyze the genes involved in the internalization and degradation of keratin monomers in Stenotrophomonas maltophilia DHHJ strain cells. Moreover, we used Co-IP with LC-MS/MS technology to search for proteins that interact with recombinant keratin monomers. RESULTS: We discovered TonB transports and molecular chaperones associating with the keratin monomer, which may play a crucial role in the transmembrane transport of keratin. Meanwhile, multiple proteases belonging to distinct families were identified as binding partners of keratin monomers, among which ATPases associated with diverse cellular activity (AAA+) family proteases are overrepresented. Four genes, including JJL50_15620, JJL50_17955 (TonB-dependent receptors), JJL50_03260 (ABC transporter ATP-binding protein), and JJL50_20035 (ABC transporter substrate-binding protein), were selected as representatives for determining their expressions under different culture conditions using qRT-PCR, and they were found to be upregulated in response to keratin degradation consistent with the data from RNA-seq and Co-IP. CONCLUSION: This study highlights the complexity of keratin biodegradation in S. maltophilia DHHJ, in which multiple pathways are involved such as protein folding, protein transport, and several protease systems. Our findings provide new insights into the mechanism of feather degradation.
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Proteínas de Bactérias , Biodegradação Ambiental , Queratinas , Stenotrophomonas maltophilia , Stenotrophomonas maltophilia/metabolismo , Stenotrophomonas maltophilia/genética , Queratinas/metabolismo , Queratinas/genética , Animais , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Plumas/metabolismo , Plumas/microbiologia , Espectrometria de Massas em Tandem , Regulação Bacteriana da Expressão Gênica , Peptídeo Hidrolases/metabolismo , Peptídeo Hidrolases/genéticaRESUMO
Background: Sepsis is a life-threatening disease characterized by multiple organ failure due to excessive activation of the inflammatory response and cytokine storm. Despite recent advances in the clinical use of anti-cytokine biologics, sepsis treatment efficacy and improvements in mortality remain unsatisfactory, largely due to the mechanistic complexity of immune regulation and cytokine interactions. Methods: In this study, a broad-spectrum anti-inflammatory and endotoxin neutralization strategy was developed based on autologous "cryo-shocked" neutrophils (CS-Neus) for the management of sepsis. Neutrophils were frozen to death using a novel liquid nitrogen "cryo-shock" strategy. The CS-Neus retained the source cell membrane structure and functions related to inflammatory site targeting, broad-spectrum inflammatory cytokines, and endotoxin (LPS) neutralizing properties. This strategy aimed to disable harmful pro-inflammatory functions of neutrophils, such as cytokine secretion. Autologous cell-based therapy strategies were employed to avoid immune rejection and enhance treatment safety. Results: In both LPS-induced sepsis mouse models and clinical patient-derived blood samples, CS-Neus treatment significantly ameliorated cytokine storms by removing inflammatory cytokines and endotoxin. The therapy showed notable anti-inflammatory therapeutic effects and improved the survival rate of mice. Discussion: The results of this study demonstrate the potential of autologous "cryo-shocked" neutrophils as a promising therapeutic approach for managing sepsis. By targeting inflammatory organs and exhibiting anti-inflammatory activity, CS-Neus offer a novel strategy to combat the complexities of sepsis treatment. Further research and clinical trials are needed to validate the efficacy and safety of this approach in broader populations and settings.
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Sepsis-induced ALI is marked by physiological, pathological, and biochemical irregularities caused by infection. Growth differentiation factor 3 (GDF3) is closely associated with the inflammatory response. Accumulating evidence has demonstrated a close relationship between GDF3 expression and the severity and prognosis of sepsis. However, the precise mechanism by which GDF3 protects against ALI induced by sepsis is still unclear. Following the intravenous administration of GDF3 in this research, we noted a rise in the survival rate, a decrease in the severity of histopathological damage as evaluated through HE staining, a decline in the count of inflammatory cells in bronchoalveolar lavage fluid (BALF), a reduction in the ratio of lung wet/dry (W/D) weight, and a noteworthy decrease in the levels of pro-inflammatory cytokines in both serum and BALF when compared to septic mice who underwent cecal ligation and puncture (CLP). These collective findings unequivocally indicate the protective effects of GDF3 against sepsis-induced ALI. In addition, the GDF3 group showed a significant reduction in the mRNA expression of Caspase-1 and NLRP3 when compared to the CLP group. Following this, we performed in vitro tests to confirm these discoveries and obtained comparable outcomes, wherein the administration of GDF3 notably decreased the levels of Caspase-1 and NLRP3 mRNA and protein in macrophages in comparison to the LPS group. Furthermore, GDF3 exhibited the capacity to reduce the secretion of inflammatory molecules from macrophages. By illuminating the mechanism by which GDF 3 regulates macrophages, this offers a theoretical basis for preventing and treating sepsis-induced ALI.