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1.
iScience ; 27(7): 110193, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38984199

RESUMO

Oyster reefs are hotspots of denitrification mediated removal of dissolved nitrogen (N), however, information on their denitrifier microbiota is scarce. Furthermore, in oyster aquaculture, triploids are often preferred over diploids, yet again, microbiome differences between oyster ploidies are unknown. To address these knowledge gaps, farmed diploid and triploid oysters were collected over an annual growth cycle and analyzed using shotgun metagenomics and quantitative microbial elemental cycling (QMEC) techniques. Regardless of ploidy, Psychrobacter genus was abundant, with positive correlations found for genes of central metabolism, DNA metabolism, and carbohydrate metabolism. MAGs (metagenome-assembled genomes) yielded multiple Psychrobacter genomes harboring norB, narH, narI, and nirK denitrification genes, indicating their functional relevance within the eastern oysters. QMEC analysis indicated the predominance of carbon (C) and nitrogen (N) cycling genes, with no discernable patterns between ploidies. Among the N-cycling genes, the nosZII clade was overrepresented, suggesting its role in the eastern oyster's N removal processes.

2.
Environ Int ; 190: 108846, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38925006

RESUMO

Natural environments play a crucial role in transmission of antimicrobial resistance (AMR). Development of methods to manage antibiotic resistance genes (ARGs) in natural environments are usually limited to the laboratory or field scale, partially due to the complex dynamics of transmission between different environmental compartments. Here, we conducted a nine-year longitudinal profiling of ARGs at a watershed scale, and provide evidence that restrictions on livestock farms near water bodies significantly reduced riverine ARG abundance. Substantial reductions were revealed in the relative abundance of genes conferring resistance to aminoglycosides (42%), MLSB (36%), multidrug (55%), tetracyclines (53%), and other gene categories (59%). Additionally, improvements in water quality were observed, with distinct changes in concentrations of dissolved reactive phosphorus, ammonium, nitrite, pH, and dissolved oxygen. Antibiotic residues and other pharmaceuticals and personal care products (PPCPs) maintain at a similarly low level. Microbial source tracking demonstrates a significant decrease in swine fecal indicators, while human fecal pollution remains unchanged. These results suggest that the reduction in ARGs was due to a substantial reduction in input of antibiotic resistant bacteria and genes from animal excreta. Our findings highlight the watershed as a living laboratory for understanding the dynamics of AMR, and for evaluating the efficacy of environmental regulations, with implications for reducing environmental risks associated with AMR on a global scale.

3.
J Cell Mol Med ; 28(12): e18469, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38899809

RESUMO

The alterations in DNA methylation and transcriptome in trophoblast cells under conditions of low oxygen and oxidative stress have major implications for pregnancy-related disorders. However, the exact mechanism is still not fully understood. In this study, we established models of hypoxia (H group) and oxidative stress (HR group) using HTR-8/SVneo trophoblast cells and performed combined analysis of genome-wide DNA methylation changes using reduced representation bisulphite sequencing and transcriptome expression changes using RNA sequencing. Our findings revealed that the H group exhibited a higher number of differentially methylated genes and differentially expressed genes than the HR group. In the H group, only 0.90% of all differentially expressed genes displayed simultaneous changes in DNA methylation and transcriptome expression. After the threshold was expanded, this number increased to 6.29% in the HR group. Notably, both the H group and HR group exhibited concurrent alterations in DNA methylation and transcriptome expression within Axon guidance and MAPK signalling pathway. Among the top 25 differentially methylated KEGG pathways in the promoter region, 11 pathways were commonly enriched in H group and HR group, accounting for 44.00%. Among the top 25 KEGG pathways in transcriptome with significant differences between the H group and HR group, 10 pathways were consistent, accounting for 40.00%. By integrating our previous data on DNA methylation from preeclamptic placental tissues, we identified that the ANKRD37 and PFKFB3 genes may contribute to the pathogenesis of preeclampsia through DNA methylation-mediated transcriptome expression under hypoxic conditions.


Assuntos
Hipóxia Celular , Metilação de DNA , Estresse Oxidativo , Transcriptoma , Trofoblastos , Humanos , Trofoblastos/metabolismo , Estresse Oxidativo/genética , Transcriptoma/genética , Hipóxia Celular/genética , Linhagem Celular , Feminino , Gravidez , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Fosfofrutoquinase-2/genética , Fosfofrutoquinase-2/metabolismo
4.
ESC Heart Fail ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38887208

RESUMO

AIMS: To retrospectively compare the long-term outcomes following atrial fibrillation (AF) ablation between heart failure (HF) with preserved ejection fraction (EF) (HFpEF) and reduced/mildly reduced EF (HFr-mrEF) patients, and to identify novel predictors of adverse clinical events. METHODS: In total, 1402 AF patients with HF who underwent successful ablation were consecutively enrolled. Adverse clinical events including all-cause death, HF hospitalization, and stroke were followed up. Cox proportional hazards models were used to assess the associations between clinical factors and events. Kaplan-Meier analysis was performed to estimate the cumulative incidences of these events. A receiver operating characteristic curve was used to test the ability of these predictors. RESULTS: During a follow-up period of 42 ± 15 months, 265 (18.9%) patients experienced adverse clinical events after ablation. The cumulative incidence of adverse clinical events was significantly higher in HFr-mrEF than in HFpEF (25.4% vs. 15.7%, P < 0.001), the similar tendency was observed on all-cause death (10.5% vs. 6.5%, P = 0.011) and HF hospitalization (17.2% vs. 10.1%, P < 0.001). After multivariate adjustment, non-paroxysmal AF [hazard ratio (HR) 1.922, 95% confidence interval (CI) 1.130-3.268, P = 0.016], LAD ≥ 45 mm (HR 2.197, 95% CI 1.206-4.003, P < 0.001), LVEF (HR 0.959, 95% CI 0.946-0.981, P < 0.001), and RAD ≥ 45 mm (HR 2.044, 95% CI 1.362-3.238, P < 0.001) remained the independent predictors for developing adverse clinical events. A predictive model performed with non-paroxysmal AF, LAD ≥ 45 mm and RAD ≥ 45 mm yielded an area under curve of 0.728 (95% CI 0.696-0.760, P < 0.001). CONCLUSIONS: AF patients with HFpEF had better long-term outcomes than those with HFr-mrEF, and moderate/severe biatrial dilation could predict adverse clinical events following catheter ablation in AF and HF patients.

5.
Comput Struct Biotechnol J ; 23: 1877-1885, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38707542

RESUMO

Transcription factors (TFs) are major contributors to gene transcription, especially in controlling cell-specific gene expression and disease occurrence and development. Uncovering the relationship between TFs and their target genes is critical to understanding the mechanism of action of TFs. With the development of high-throughput sequencing techniques, a large amount of TF-related data has accumulated, which can be used to identify their target genes. In this study, we developed TFTG (Transcription Factor and Target Genes) database (http://tf.liclab.net/TFTG), which aimed to provide a large number of available human TF-target gene resources by multiple strategies, besides performing a comprehensive functional and epigenetic annotations and regulatory analyses of TFs. We identified extensive available TF-target genes by collecting and processing TF-associated ChIP-seq datasets, perturbation RNA-seq datasets and motifs. We also obtained experimentally confirmed relationships between TF and target genes from available resources. Overall, the target genes of TFs were obtained through integrating the relevant data of various TFs as well as fourteen identification strategies. Meanwhile, TFTG was embedded with user-friendly search, analysis, browsing, downloading and visualization functions. TFTG is designed to be a convenient resource for exploring human TF-target gene regulations, which will be useful for most users in the TF and gene expression regulation research.

6.
Sci Adv ; 10(15): eadk3201, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38598629

RESUMO

Disruptions in metal balance can trigger a synergistic interplay of cuproptosis and ferroptosis, offering promising solutions to enduring challenges in oncology. Here, we have engineered a Cellular Trojan Horse, named MetaCell, which uses live neutrophils to stably internalize thermosensitive liposomal bimetallic Fe-Cu MOFs (Lip@Fe-Cu-MOFs). MetaCell can instigate cuproptosis and ferroptosis, thereby enhancing treatment efficacy. Mirroring the characteristics of neutrophils, MetaCell can evade the immune system and not only infiltrate tumors but also respond to inflammation by releasing therapeutic components, thereby surmounting traditional treatment barriers. Notably, Lip@Fe-Cu-MOFs demonstrate notable photothermal effects, inciting a targeted release of Fe-Cu-MOFs within cancer cells and amplifying the synergistic action of cuproptosis and ferroptosis. MetaCell has demonstrated promising treatment outcomes in tumor-bearing mice, effectively eliminating solid tumors and forestalling recurrence, leading to extended survival. This research provides great insights into the complex interplay between copper and iron homeostasis in malignancies, potentially paving the way for innovative approaches in cancer treatment.


Assuntos
Ferroptose , Neoplasias , Animais , Camundongos , Cobre , Inflamação , Lipossomos
7.
EMBO Mol Med ; 16(5): 1143-1161, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565806

RESUMO

Accurately predicting and selecting patients who can benefit from targeted or immunotherapy is crucial for precision therapy. Trophoblast cell surface antigen 2 (Trop2) has been extensively investigated as a pan-cancer biomarker expressed in various tumours and plays a crucial role in tumorigenesis through multiple signalling pathways. Our laboratory successfully developed two 68Ga-labelled nanobody tracers that can rapidly and specifically target Trop2. Of the two tracers, [68Ga]Ga-NOTA-T4, demonstrated excellent pharmacokinetics in preclinical mouse models and a beagle dog. Moreover, [68Ga]Ga-NOTA-T4 immuno-positron emission tomography (immunoPET) allowed noninvasive visualisation of Trop2 heterogeneous and differential expression in preclinical solid tumour models and ten patients with solid tumours. [68Ga]Ga-NOTA-T4 immunoPET could facilitate clinical decision-making through patient stratification and response monitoring during Trop2-targeted therapies.


Assuntos
Antígenos de Neoplasias , Moléculas de Adesão Celular , Neoplasias , Tomografia por Emissão de Pósitrons , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/imunologia , Humanos , Animais , Moléculas de Adesão Celular/metabolismo , Neoplasias/diagnóstico por imagem , Neoplasias/imunologia , Camundongos , Cães , Tomografia por Emissão de Pósitrons/métodos , Feminino , Anticorpos de Domínio Único/imunologia
8.
ACS Appl Mater Interfaces ; 16(12): 15177-15192, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38471076

RESUMO

Halloysite nanotubes (HNTs) are one-dimensional clay nanomaterials featuring distinct tubular structures and unique surface charges. HNTs can readily form ordered assembly structures under specific conditions, which shows significant potential applications in optical and biological fields. In this study, sodium hexametaphosphate (SHMP) was employed as a stabilizer to prepare polymer spherulite-like patterns via the evaporation-induced self-assembly (EISA) technique. The incorporation of SHMP enhanced the repulsion force among the nanotubes and the surface potential, which facilitated the orderly deposition of HNTs. The influence of HNT concentration, SHMP concentration, drying temperature, and substrate on the polymer spherulites-like pattern has been investigated in detail. The optimal conditions were 10 wt % HNT dispersion, 0.6 wt % SHMP concentration, 30 °C as drying temperature, and glass substrates. In addition, by changing the droplet volume and shape of the three-phase contact line, patterns of different sizes and shapes can be achieved. Bovine serum albumin or metal salt compounds were incorporated into the dispersion of SHMP-modified HNTs, which altered the charge and the self-assembled patterns with different area ratios. Thus, this technology can be utilized for the analysis and comparison of protein and metal ion concentration accurately. This study creates the correlation between the structural parameters and the preparation process involved in creating polymer spherulite-like patterns of modified HNTs and offers fresh insights into potential applications for the self-assembly of HNT droplets in the realms of anticounterfeiting and solution concentration analysis.

9.
Ther Apher Dial ; 28(3): 390-398, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38444376

RESUMO

INTRODUCTION: This study aims to analyze the risk factors for severe fatigue in maintenance hemodialysis (MHD) patients and develop a clinical prediction model to help doctors and patients prevent severe fatigue. METHODS: Multicentre MHD patients were included in this study. The objective was to investigate the risk factors for severe fatigue in MHD patients and develop a prediction model. RESULTS: A total of 243 MHD patients were included in the study, and the incidence of severe fatigue was found to be 20.99%. Using age, body mass index, total cholesterol, and albumin levels, a predictive nomogram for fatigue was constructed. In the training set, the nomogram had an area under the curve of 0.851, sensitivity of 82.86%, specificity of 81.76%, and c-index of 0.851. The nomogram was accurate in calibration and proved to be clinically useful. CONCLUSION: The nomogram developed in this study is a practical and reliable tool for quickly identifying severe fatigue in MHD patients.


Assuntos
Fadiga , Nomogramas , Diálise Renal , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , China/epidemiologia , Estudos Transversais , Fadiga/etiologia , Fadiga/epidemiologia , Fadiga/diagnóstico , Incidência , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
10.
Chem Sci ; 15(6): 2243-2256, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38332816

RESUMO

Cytokine storm is a potentially life-threatening immune response typically correlated with lung injury, particularly in people with underlying disease states, such as pneumonia. Therefore, the prompt treatment of cytokine storm is essential for successful recovery from a potentially fatal condition. Herein, a living anti-inflammatory Biorobot (firefighter), composed of neutrophils encapsulating mannose-decorated liposomes of the NF-κB inhibitor TPCA-1 and STING inhibitor H-151 (M-Lip@TH, inflammatory retardant), is developed for alleviating hyperinflammatory cytokine storm through targeting multiple inflammatory pathways in macrophages. Biorobot fully inherits the chemotaxis characteristics of neutrophils, and efficiently delivers and releases therapeutic M-Lip@TH at the inflammatory site. Subsequently, M-Lip@TH selectively targets macrophages and simultaneously blocks the transcription factor NF-κB pathway and STING pathway, thereby preventing the overproduction of cytokines. Animal studies show that Biorobot selectively targets LPS-induced acute lung injury, and not only inhibits the NF-κB pathway to suppress the release of various pro-inflammatory cytokines and chemokines, but also blocks the STING pathway to prevent an overactive immune response, which helps to neutralize cytokine storms. Particularly, Biorobot reduces lung inflammation and injury, improves lung function, and increases the survival rates of pneumonia mice. Therefore, Biorobot represents a rational combination therapy against cytokine storm, and may provide insights into the treatment of diseases involving overactive immune responses.

11.
Adv Mater ; 36(18): e2311661, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38252744

RESUMO

Brain infections, frequently accompanied by significant inflammation, necessitate comprehensive therapeutic approaches targeting both infections and associated inflammation. A major impediment to such combined treatment is the blood-brain barrier (BBB), which significantly restricts therapeutic agents from achieving effective concentrations within the central nervous system. Here, a neutrophil-centric dual-responsive delivery system, coined "CellUs," is pioneered. This system is characterized by live neutrophils enveloping liposomes of dexamethasone, ceftriaxone, and oxygen-saturated perfluorocarbon (Lipo@D/C/P). CellUs is meticulously engineered to co-deliver antibiotics, anti-inflammatory agents, and oxygen, embodying a comprehensive strategy against brain infections. CellUs leverages the intrinsic abilities of neutrophils to navigate through BBB, accurately target infection sites, and synchronize the release of Lipo@D/C/P with local inflammatory signals. Notably, the incorporation of ultrasound-responsive perfluorocarbon within Lipo@D/C/P ensures the on-demand release of therapeutic agents at the afflicted regions. CellUs shows considerable promise in treating Staphylococcus aureus infections in mice with meningitis, particularly when combined with ultrasound treatments. It effectively penetrates BBB, significantly eliminates bacteria, reduces inflammation, and delivers oxygen to the affected brain tissue, resulting in a substantial improvement in survival rates. Consequently, CellUs harnesses the natural chemotactic properties of neutrophils and offers an innovative pathway to improve treatment effectiveness while minimizing adverse effects.


Assuntos
Antibacterianos , Barreira Hematoencefálica , Neutrófilos , Staphylococcus aureus , Animais , Neutrófilos/metabolismo , Camundongos , Barreira Hematoencefálica/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/uso terapêutico , Fluorocarbonos/química , Lipossomos/química , Dexametasona/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Encéfalo/metabolismo , Ceftriaxona/uso terapêutico , Oxigênio/metabolismo , Humanos , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Bioengenharia/métodos
12.
J Hazard Mater ; 465: 133392, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38171204

RESUMO

Antibiotic resistance is an escalating global concern, leading to millions of annual deaths worldwide. Human activities can impact antibiotic resistance gene (ARG) prevalence in aquatic ecosystems, but the intricate interplay between anthropogenic disturbances and river system resilience, and their respective contributions to the dynamics of different river segments, remains poorly understood. In this study, we investigate the antibiotic resistome and microbiome in water and sediment samples from two distinct sub-watersheds within a specific watershed. Results show a decrease in the number of core ARGs downstream in water, while sediments near densely populated areas exhibit an increase. PCoA ordination reveals clear geographic clustering of resistome and microbiome among samples from strong anthropogenic disturbed areas, reservoir areas, and estuary area. Co-occurrence networks highlight a higher connectivity of mobile genetic elements (MGEs) in disturbed areas compared to reservoir areas, presenting a threat to densely populated areas. Water quality parameters and antibiotics concentration were the key factors shaping the ARG profiles in sediment samples from urban regions. Overall, our study reveals distinct patterns of ARGs in sediment and water samples, emphasizing the importance of considering both anthropogenic and natural factors in comprehending and managing ARG distribution in river systems.


Assuntos
Genes Bacterianos , Microbiota , Humanos , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Rios
13.
Huan Jing Ke Xue ; 45(1): 576-583, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216506

RESUMO

Urban wetland parks are an important practice for urban wetland protection and utilization due to the vast ecosystem service value. As emerging contaminants, antibiotic resistance genes (ARGs) are great attractions for environmental research and public concerns. Based on high-throughput qPCR and high-throughput amplicon sequencing techniques, we investigated the occurrence, abundance, and distribution profiles of antibiotic resistance genes in the aquatic environment of Xiamen urban wetland parks (five sites). The influencing factors and driving mechanisms of antibiotic resistance genes were deciphered on the basis of microbial community structure and water quality. Diverse and abundant ARGs were observed and coexisted in urban wet parks. A total of 217 ARGs were detected in the water body of urban wetland parks, with an abundance up to 6.48×109 copies·L-1. Urban wetland parks were important hotspots and repositories of the antibiotic resistome. A total of nine bacterial genera, including Marivivens, NS5_marine_group, and Planktomarina, were identified as the potential carriers of diverse resistance genes (41 ARGs). The microbial communities could alone explain 51% of alterations in the antibiotic resistome in the aquatic environment of the urban wetland parks. Therefore, the microbial community was the key driving force for the occurrence and evolution of ARGs in urban wetland parks. Based on the results, with the presence of ARGs and antibiotic resistance bacteria, it is suggested that the water environments of urban wetland parks have potential risks of water ecological security and human health, and it is necessary to further enhance the research and control of microbial contaminants in the aquatic environment of urban wetland parks.


Assuntos
Genes Bacterianos , Microbiota , Humanos , Genes Bacterianos/genética , Áreas Alagadas , Antibacterianos/análise , Resistência Microbiana a Medicamentos/genética , Bactérias/genética
14.
J Adv Res ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38199454

RESUMO

INTRODUCTION: Apricot (Prunus armeniaca L.) fruits are highly perishable and prone to quality deterioration during storage and transportation. OBJECTIVES: To investigate the effects of LED white light treatment on postharvest ripening of fruits using metabolomics, transcriptomics, and ATAC-Seq analysis. METHODS: Fruits were exposed to 5 µmol m-2 s-1 LED white light for 12 h followed by 12 h of darkness at 20 °C daily for 12 days. The effects of the treatments on the physiological and nutritional quality of the fruits were evaluated. These data were combined with transcriptomic, metabolomic, and ATAC-Seq data from fruits taken on 8 d of treatment to provide insight into the potential mechanism by which LED treatment delays ripening. RESULTS: LED treatment activated pathways involved in ascorbate and aldarate metabolism and flavonoid and phenylpropanoid biosynthesis. Specifically, LED treatment increased the expression of UDP-sugar pyrophosphorylase (USP), L-ascorbate peroxidase (AO), dihydroflavonol 4-reductase (DFR), chalcone synthase (CHS), and caffeoyl-CoA O-methyltransferase (CCOAOMT1), leading to the accumulation of caffeoyl quinic acid, epigallocatechin, and dihydroquercetin and the activation of anthocyanin biosynthesis. LED treatment also affected the expression of genes associated with plant hormone signal transduction, fruit texture and color transformation, and antioxidant activity. The notable genes affected by LED treatment included 1-aminocyclopropane-1-carboxylate synthase (ACS), 1-aminocyclopropane-1-carboxylate oxidase (ACO), hexokinase (HK), lipoxygenase (LOX), malate dehydrogenase (MDH), endoglucanase (CEL), various transcription factors (TCP, MYB, EFR), and peroxidase (POD). ATAC-Seq analysis further revealed that LED treatment primarily regulated phenylpropanoid biosynthesis. CONCLUSION: The results obtained in this study provide insights into the effects of LED light exposure on apricot fruits ripening. LEDs offer a promising approach for extending the shelf life of other fruits and vegetables.

15.
Adv Mater ; 35(49): e2304172, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37801656

RESUMO

Although tumor models have revolutionized perspectives on cancer aetiology and treatment, current cell culture methods remain challenges in constructing organotypic tumor with in vivo-like complexity, especially native characteristics, leading to unpredictable results for in vivo responses. Herein, the bioorthogonal nanoengineering strategy (BONE) for building photothermal dynamic tumor spheroids is developed. In this process, biosynthetic machinery incorporated bioorthogonal azide reporters into cell surface glycoconjugates, followed by reacting with multivalent click ligand (ClickRod) that is composed of hyaluronic acid-functionalized gold nanorod carrying dibenzocyclooctyne moieties, resulting in rapid construction of tumor spheroids. BONE can effectively assemble different cancer cells and immune cells together to construct heterogenous tumor spheroids is identified. Particularly, ClickRod exhibited favorable photothermal activity, which precisely promoted cell activity and shaped physiological microenvironment, leading to formation of dynamic features of original tumor, such as heterogeneous cell population and pluripotency, different maturation levels, and physiological gradients. Importantly, BONE not only offered a promising platform for investigating tumorigenesis and therapeutic response, but also improved establishment of subcutaneous xenograft model under mild photo-stimulation, thereby significantly advancing cancer research. Therefore, the first bioorthogonal nanoengineering strategy for developing dynamic tumor models, which have the potential for bridging gaps between in vitro and in vivo research is presented.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Carcinogênese , Esferoides Celulares/patologia , Microambiente Tumoral
16.
Int J Biol Macromol ; 253(Pt 5): 127264, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37804892

RESUMO

In this study, we report the development of a sustainable polymer system with 50 wt% lignin content, suitable for additive manufacturing and high value-added utilization of lignin. The plasticized polylactic acid (PLA) was incorporated with lignin to develop the bendable and malleable green composites with excellent 3D printing adaptability. The biocomposites exhibit increases of 765.54 % and 125.27 % in both elongation and toughness, respectively. The plasticizer enhances the dispersion of lignin and the molecular mobility of the PLA chains. The good dispersion of lignin particles within the structure and the reduction of chemical cross-linking promote the local relaxation of the polymer chains. The good local relaxation of the polymer chains and the high flexibility allow to obtain a better integration between the printed layers with good printability. This research demonstrates the promising potential of this composite system for sustainable manufacturing and provides insights into novel material design for high-value applications of lignin.


Assuntos
Lignina , Poliésteres , Polímeros , Plastificantes
17.
J Hazard Mater ; 460: 132511, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37708648

RESUMO

The granular activated carbon (GAC) sandwich modification to slow sand filtration could be considered as a promising technology for improved drinking water quality. Biofilms developed on sand and GAC surfaces are expected to show a functional diversity during the biofiltration. Bench-scale GAC sandwich biofilters were set-up and run continuously with and without antibiotic exposure. Surface sand (the schmutzdecke) and GAC biofilms were sampled and subject to high-throughput qPCR for antibiotic resistance gene (ARG) analysis and 16 S rRNA amplicon sequencing. Similar diversity of ARG profile was found in both types of biofilms, suggesting that all ARG categories decreased in richness along the filter bed. In general, surface sand biofilm remained the most active layer with regards to the richness and abundance of ARGs, where GAC biofilms showed slightly lower ARG risks. Network analysis suggested that 10 taxonomic genera were implicated as possible ARG hosts, among which Nitrospira, Methyloversatilis and Methylotenera showed the highest correlation. Overall, this study was the first attempt to consider the whole structure of the GAC sandwich biofilter and results from this study could help to further understand the persistence of ARGs and their association with the microbial community in drinking water biofiltration system.


Assuntos
Carvão Vegetal , Água Potável , Areia , Antibacterianos , Bactérias/genética , Biofilmes , Resistência Microbiana a Medicamentos/genética
18.
Small ; 19(52): e2305343, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37635101

RESUMO

Design high-loading with superior activity and high atomic efficiency has consistently been a new frontier of heterogeneous catalysis while challenging in synthetic technology. In this work, a universal solid-state strategy is proposed for large scalable production of high-loading Ir clusters on porous hollow carbon nanobowls (Ir CSs/PHCNBs). The strong electronic interaction between metallic Ir cluster and C on PHCNBs leads to electron redistribution, which significantly improves the electron transfer rate on the interface. The obtained Ir CSs/PHCNBs only require overpotentials of 35, 34, and 37 mV for the hydrogen evolution reaction (HER) with stable outputting of 10 mA cm-2 under acidic, alkaline, and neutral conditions, respectively, which exceeds the state-of-the-art HER electrocatalysts. Meanwhile, the Tafel slopes of Ir CSs/PHCNBs for the HER process are 23.07, 48.76, and 28.95 mV dec-1 , greatly lower than that of PHCNBs (152.73, 227.96, and 140.29 mV dec-1 ) and commercial Pt/C (20%) (36.33, 66.10, and 36.61 mV dec-1 ). These results provide a new strategy for the universal synthesis of clusters catalysts and insight into understanding the interface effects between clusters and carbon substrate, facilitating the industrial application of hydrogen production.

19.
Int J Biol Macromol ; 253(Pt 1): 126562, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37652328

RESUMO

Light-responsive shape memory polymers are attractive as they can be activated through remote and spatially-controlled light. In this work, 4D printing of poly(lactic acid) (PLA) composites with a near-infrared light-responsive was achieved by using the simple melt blending method and adding 3 wt% of lignin. Lignin with a conjugated structure was used as the photothermal conversion module. The composites exhibited significant photothermal effects under near-infrared (808 nm) laser irradiation, and the laser irradiation was also effective in initiating and controlling the shape memory. The structure of lignin can be improved by the action of dicumyl peroxide (DCP) to enhance the interfacial adhesion between polyamide elastomer (PAE) and polylactic acid (PLA), reduce the size of dispersed phases, and serve as an effective rheological modifier to exhibit the ideal melt viscosity required for 3D printing of composites. The good mechanical, thermal stability, and rheological properties provide assurance for the 4D printing of composites. This research provides an environmentally friendly and practical method for creating composites that have the potential to serve as ideal actuator components in a range of applications.


Assuntos
Elastômeros , Lignina , Raios Infravermelhos , Poliésteres , Impressão Tridimensional
20.
ACS Nano ; 17(17): 16461-16477, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37596997

RESUMO

Cytokine storm is a common complication of COVID-19 pneumonia and has been proven to contribute to high mortality rates. However, current treatment approaches exhibit limited potential to balance immune response and overproduction of inflammatory cytokines, leading to poor therapeutic outcomes. Herein, a smart bioengineered neutrophil, Extinguisher, composed of live neutrophils encapsulating the liposome formulation of NF-κB suppressor MLN4924 and STING inhibitor H-151 (Lip@MH), is developed for alleviating the hyperinflammatory cytokine storm. Extinguisher inherits motility and chemotaxis characteristics of neutrophils, allowing for the specific delivery and sustained release of Lip@MH within inflamed tissues. Subsequently, Lip@MH effectively transports anti-inflammatory agents into macrophages and synergistically inhibits inflammatory pathways of NF-κB and STING, leading to decreased production of cytokines. In vivo studies demonstrate that Extinguisher not only selectively accumulates at the site of pneumonia caused by Pseudomonas aeruginosa-induced acute lung injury but inhibits the production of inflammatory factors through regulating NF-κB/STING signaling pathways, thereby effectively calming cytokine storm. Importantly, Extinguisher significantly improves therapeutic benefits and survival in mice with acute pneumonia. Therefore, Extinguisher represents an appropriate combination of cell therapy and immunoregulation for cytokine storm intervention and may bring insights into the treatment of COVID-19 pneumonia.


Assuntos
COVID-19 , Pneumonia , Animais , Camundongos , Neutrófilos , NF-kappa B , Síndrome da Liberação de Citocina , Macrófagos , Citocinas
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