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1.
J Environ Manage ; 352: 120071, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38246103

RESUMEN

The effectiveness of biofertilizers as a cost-effective crop yield enhancer can be compromised by residual soil pollutants. However, the impact of accumulated polyadipate/butylene terephthalate microplastics (PBAT-MPs) from biodegradable mulch films on biofertilizer application and the consequent growth of crop plants remains unclear. Here, the effects of different levels of PBAT-MPs in soil treated with Bacillus amyloliquefaciens biofertilizer were assessed in a four-week potted experiment. PBAT-MPs significantly decreased the growth-promoting effect of the biofertilizer on Brassica chinensis L., resulting in a notable reduction in both above- and belowground biomass (up to 52.91% and 57.53%, respectively), as well as nitrate and crude fiber contents (up to 12.18% and 13.64%, respectively). In the rhizosphere microenvironment, PBAT-MPs increased soil organic carbon by 2.63-fold and organic matter by 2.68-fold, while enhancing sucrase (from 67.55% to 108.89%) and cellulase (from 31.26% to 49.10%) activities. PBAT-MPs also altered the rhizospheric bacterial community composition/diversity, resulting in more complex microbial networks. With regard to microbial function, PBAT-MPs impacted carbon metabolic function by inhibiting the 3-hydroxypropionate/4-hydroxybutyrate fixation pathway and influencing chitin and lignin degradation processes. Overall, the rhizospheric microbial profiles (composition, function, and network interactions) were the main contributors to plant growth inhibition. This study provides a practical case and theoretical basis for rational use of biodegradable mulch films and indicates that the residue of biodegradable films needs pay attention.


Asunto(s)
Alquenos , Carbono , Microplásticos , Plásticos , Suelo
2.
Cell Mol Life Sci ; 79(11): 551, 2022 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-36244032

RESUMEN

Periodontal ligament (PDL) cells are a promising tool for periodontal regeneration therapy. Achieving a sufficient number of PDL cells is essential to PDL regeneration. In our study, appropriate flow shear stress (FSS, 1-6 dyn/cm2) promotes the proliferation of PDL cells. FSS remodels cytoskeleton and focal adhesion in a duration-dependent manner. FSS induces PDL cells to form the actin cap within 10 min, flattens the nuclei, and increases the nuclear pore size, which promotes nuclear translocation of Yes-associated protein (YAP). FSS activates p38, which plays a dual function in YAP regulation. p38 regulates the phosphorylation of Akt and cofilin, as well as induced F-actin polymerization to induce YAP activity. In addition, p38 inhibits pLATS and consecutively regulates angiomotin (AMOT) and YAP phosphorylation. AMOT competitively binds to F-actin and YAP to participate in FSS-mediated YAP nuclear translocation and cell proliferation. Taken collectively, our results provide mechanistic insights into the role of p38-AMOT-YAP in FSS-mediated PDL cells proliferation and indicate potential applications in dental regenerative medicine.


Asunto(s)
Actinas , Ligamento Periodontal , Factores Despolimerizantes de la Actina/metabolismo , Actinas/metabolismo , Angiomotinas , Proliferación Celular , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Señalizadoras YAP
3.
Int J Mol Sci ; 24(16)2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37628990

RESUMEN

The influence of nanoscale surface topography on protein adsorption is highly important for numerous applications in medicine and technology. Herein, ferritin adsorption at flat and nanofaceted, single-crystalline Al2O3 surfaces is investigated using atomic force microscopy and X-ray photoelectron spectroscopy. The nanofaceted surfaces are generated by the thermal annealing of Al2O3 wafers at temperatures above 1000 °C, which leads to the formation of faceted saw-tooth-like surface topographies with periodicities of about 160 nm and amplitudes of about 15 nm. Ferritin adsorption at these nanofaceted surfaces is notably suppressed compared to the flat surface at a concentration of 10 mg/mL, which is attributed to lower adsorption affinities of the newly formed facets. Consequently, adsorption is restricted mostly to the pattern grooves, where the proteins can maximize their contact area with the surface. However, this effect depends on the protein concentration, with an inverse trend being observed at 30 mg/mL. Furthermore, different ferritin adsorption behavior is observed at topographically similar nanofacet patterns fabricated at different annealing temperatures and attributed to different step and kink densities. These results demonstrate that while protein adsorption at solid surfaces can be notably affected by nanofacet patterns, fine-tuning protein adsorption in this way requires the precise control of facet properties.


Asunto(s)
Ferritinas , Medicina , Adsorción , Microscopía de Fuerza Atómica , Espectroscopía de Fotoelectrones
4.
J Hazard Mater ; 467: 133709, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38330650

RESUMEN

Microplastics (MPs) from the incomplete degradation of agricultural mulch can stress the effectiveness of biofertilizers and ultimately affect the rhizosphere environment of crops. Yet, the involved mechanisms are poorly known and robust empirical data is generally lacking. Here, conventional polyethylene (PE) MPs and poly(butylene adipate-co-butylene terephthalate) (PBAT) / poly(lactic acid) (PLA) biodegradable MPs (PBAT-PLA BioMPs) were investigated to assess their potential impact on the rhizosphere environment of Brassica parachinensis in the presence of Bacillus amyloliquefaciens biofertilizer. The results revealed that both MPs caused different levels of inhibited crop both above- and belowground crop biomass (up to 50.11% and 57.09%, respectively), as well as a significant decrease in plant height (up to 48.63% and 25.95%, respectively), along with an imbalance of microbial communities. Transcriptomic analyses showed that PE MPs mainly affected root's vitamin metabolism, whereas PBAT-PLA BioMPs mainly interfered with the lipid's enrichment. Metabolomic analyses further indicated that PE MPs interfered with amino acid synthesis that involved in crops' oxidative stress, and that PBAT-PLA BioMPs mainly affected the pathways associated with root growth. Additionally, PBAT-PLA BioMPs had a bigger ecological negative impact than did PE MPs, as evidenced by more pronounced alterations in root antioxidant abilities, a higher count of identified differential metabolites, more robust interrelationships among rhizosphere parameters, and a more intricate pattern of impacts on rhizosphere metrics. This study highlights the MPs' impact on crop rhizosphere in a biofertilizer environment from a rhizosphere multi-omics perspective, and has theoretical implications for scientific application of biofertilizers.


Asunto(s)
Microplásticos , Multiómica , Plásticos , Rizosfera , Polietileno , Productos Agrícolas , Poliésteres
5.
J Hazard Mater ; 466: 133581, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38271872

RESUMEN

Microplastics (MPs) have emerged as a significant global environmental concern, particularly within agricultural soil systems. The extensive use of plastic film mulching in cotton cultivation has led to the alarming presence of MP pollution in cotton fields. However, the uptake and effects of MPs on the growth of cotton plants are poorly understood. In this study, we conducted a comprehensive analysis of hydroponically cultured cotton seedlings at the phenotypic, transcriptional, and metabolic levels after exposure to carboxyl-modified polystyrene microplastics (PS-COOH). Treatment with three concentrations of PS-COOH (100, 300, and 500 mg/L) resulted in notable growth inhibition of treated plants and exhibited a dose-dependent effect. And, PS-COOH can invade cotton roots and be absorbed through the intercellular spaces via apoplastic uptake, with accumulation commensurate with treatment duration. Transcriptomic analysis showed significant up-regulation of genes associated with antioxidant activity in response to 300 mg/L PS-COOH treatment, suggesting the induction of oxidative stress. In addition, the PS-COOH treatment activated the phenylpropanoid biosynthesis pathway, leading to lignin and flavonoid accumulation, and altered sucrose catabolism. These findings illustrate the absorption and effects of MPs on cotton seedlings and offer valuable insights into the potential toxicity of MPs to plants in soil mulched with plastic film.


Asunto(s)
Gossypium , Microplásticos , Microplásticos/toxicidad , Plásticos/toxicidad , Poliestirenos/toxicidad , Suelo
6.
Chemosphere ; 358: 142152, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38679178

RESUMEN

In recent years, filamentous algae blooms and microplastics (MPs) pollution have become two major ecological and environmental problems in urban water systems. In order to solve these two problems at the same time, this study explored the loading capacity of MPs on fresh filamentous algae, and successfully synthesized magnetic filamentous algae biochar loading with Fe3O4 by hydrothermal method, with the purpose of removing MPs from water. The magnetic filamentous algal biochar was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and so on. Experiments on adsorption kinetics, adsorption isotherms and optimum pH were carried out to explore the adsorption mechanism of MPs on magnetic filamentous algal biochar. The adsorption kinetics and adsorption isotherm models were evaluated, and the selection criterion for the appropriate model was determined by using the residual sum of squares (RSS) and Bayesian information criterion (BIC). Microscope images revealed that fresh filamentous algae could interact with MPs in the form of entanglement, adhesion and encapsulation. The average load of MPs in filamentous algae samples was 14.1 ± 5 items/g dry weight. The theoretical maximum adsorption capacities of polystyrene MPs (PS-MPs) by raw biochar (A500) and magnetic biochar with Fe3O4 (M2A500) were 176.99 mg/g and 215.58 mg/g, respectively. The adsorbent materials gave better reusability because they could be reused up to five times. Overall, these findings have provided new insights into the use of filamentous algae for in situ remediation of fluvial MPs pollution, as well as feasible strategies for the recycling of algal waste.


Asunto(s)
Carbón Orgánico , Microplásticos , Contaminantes Químicos del Agua , Carbón Orgánico/química , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Cinética
7.
Small Methods ; 7(5): e2201327, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37075716

RESUMEN

In the treatment of solid tumors, the complex barriers composed of cancer-associated fibroblasts (CAFs) prevent drug delivery and T cells infiltration into tumor tissues. Although nanocarriers hold great prospects in drug delivery, fibrosis causes the biological barrier and immunosuppressive tumor microenvironment (ITM) that impairs the anti-tumor efficacy of nanocarriers. Here, a small dendritic macromolecule loaded with doxorubicin (PAMAM-ss-DOX) (DP) is synthesized and encapsulated into pH-responsive nanoliposome, together with adjuvant toll-like receptor 7/8 (TLR7/8) agonist resiquimod (R848) and losartan (LOS). The pH-responsive liposome facilitates the simultaneous and effective delivery of DP, R848, and LOS, which can decompose and release these drugs under the acidic tumor microenvironment. The small sized DP (≈25 nm) with the ability to penetrate into tumor tissue and immunogenic cell death (ICD) can reverse the ITM and elicit immune response, which is equivalent to the effect of an in situ vaccine. Moreover, LOS reduces the activity of CAFs effectively, which can contribute to the infiltration of T cells. Therefore, this nano-platform provides a new therapeutic strategy for enhanced chemo-immunotherapy.


Asunto(s)
Liposomas , Neoplasias , Humanos , Liposomas/farmacología , Microambiente Tumoral , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Sistemas de Liberación de Medicamentos , Inmunoterapia , Neoplasias/tratamiento farmacológico
8.
Biomaterials ; 281: 121373, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35063742

RESUMEN

Polyphenols are potent antioxidants, but their poor oral bioavailability owing to intrinsic insolubility and low permeability significantly hampers their effectiveness for clinical translation. Herein, upper intestinal absorptive polymer-lipid hybrid nanoparticles (PLN) was designed by exploiting the lipidic core for drug encapsulation and the decanoic acid conjugated rapeseed protein as the biopolymeric shell for gastrointestinal stability, retention and permeability. Polyphenol ellagic acid loaded core-shell PLN (EA-PLN(C/S)) was characterized of favorable physicochemical properties in simulated gastric- and intestinal fluids, including high drug loading capacity, slow drug release and prolonged stability. In Caco-2 monolayers, the cellular transport of EA-PLN(C/S) involved dual-paracellular and endocytosis pathways. Compared to drug in suspension or lipidic core nanoparticles, orally administered EA-PLN(C/S) was retained longer and more permeable via the duodenum and jejunum of upper intestine, resulting in up to 5.3-fold and 1.4-fold enhancement in the extent of drug absorption and colonic accumulation, respectively. In an acute colitis murine model, EA-PLN(C/S) at 6 mg/kg low dose markedly reduced colonic lipid peroxidation in contrast to no antioxidant effect in other EA formulations. This work suggests that integration of engineered plant protein biopolymer with lipid nanoparticles created unique oral drug delivery systems enabling intestinal site-specific absorption for effective antioxidant therapeutics.


Asunto(s)
Nanopartículas , Polifenoles , Administración Oral , Animales , Células CACO-2 , Ácidos Decanoicos , Portadores de Fármacos , Humanos , Absorción Intestinal , Liposomas , Ratones , Proteínas de Plantas , Polímeros
9.
Bioresour Technol ; 337: 125453, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34320738

RESUMEN

The utilization of lignin as carbonaceous material for pollution adsorption provides an alternative way for lignocellulose valorization. Here in, lignin-based adsorbents (i.e., LC-A, LC-B, and LC-C) were prepared and used for the removal of o-DCB (a toxic gaseous pollutant). LC-B exhibited the best adsorption capacity (718.2 mg/g) when comparing with LC-A (93.1 mg/g), LC-C (10.2 mg/g), and activated carbon (72.7 mg/g). LC-B also demonstrated excellent recycling stability with the adsorption capacity of 710.8 mg/g after five runs. More importantly, LC-B supported Ru adsorbent catalyst could effectively remove o-DCB with removal rate >80% under a wide range of temperature (50-300°C). The excellent performance of lignin-based adsorbents could be attributed to its abundant pore structure, high specific surface area (1618.55 m2/g), enhanced graphitization degree as well as the abundant hydroxyl functional groups. The present work provided a cost-effective strategy for pollution control by lignin-based material.


Asunto(s)
Carbón Orgánico , Lignina , Adsorción , Contaminación Ambiental , Temperatura
10.
ACS Appl Mater Interfaces ; 12(15): 17936-17948, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32208630

RESUMEN

To improve water solubility and bioavailability, curcumin (Cur) was encapsulated by liposomes (Cur-Lip), which was further coated with thiolated chitosan (CSSH) to form liposomal hydrogels (CSSH/Cur-Lip gel). The hydrogels were thermosensitive with in situ injectable performance, which were fluidic at room temperature and gelled quickly at 37 °C. The cumulative release ratio of the 200 µM CSSH/Cur-Lip gel was 31.57 ± 1.34% at 12 h, which could effectively delay the release of curcumin. Worthily, the resilient hydrogels were compressive even after five cycles of compression. The cytotoxicity test indicated that the liposomal hydrogels had good cytocompatibility, but after encapsulation of curcumin, MCF-7 cells were suppressed and killed dramatically after 72 h. The in vivo breast cancer recurrence experiment showed that the CSSH/Cur-Lip gel inhibited breast cancer recurrence after tumors were resected, and the tissue of defect in the CSSH/Cur-Lip gel group was repaired. The results showed that the drug-loaded liposomal hydrogels can deliver curcumin continuously and exerted an excellent tumoricidal effect in vitro and in vivo. The injectable, in situ-formable, and thermosensitive CSSH/Cur-Lip gel can be designed as a promising novel drug delivery vehicle to be used as carriers for local accurate and sustained drug delivery to minimize burst release and as tissue engineering scaffolds for tissue regeneration after tumor resection.


Asunto(s)
Antineoplásicos/química , Quitosano/química , Curcumina/química , Hidrogeles/química , Liposomas/química , Compuestos de Sulfhidrilo/química , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Supervivencia Celular/efectos de los fármacos , Fuerza Compresiva , Curcumina/farmacología , Curcumina/uso terapéutico , Femenino , Humanos , Células MCF-7 , Ratones , Ratones Desnudos
11.
J Hazard Mater ; 229-230: 115-21, 2012 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-22749970

RESUMEN

The electro-Fenton (E-Fenton) treatment of landfill leachate concentrates was investigated in this study. The concentrates were generated from nanofiltration of biologically pretreated landfill leachate, and contained high concentrations of refractory organics and inorganic salts. During the E-Fenton treatment, H(2)O(2) was electrochemically produced at a carbon-polytetrafluorethylene (PTFE) cathode with oxygen feeding. The in situ generated H(2)O(2) then reacted with Fe(2+) that was added into the concentrates to bring about Fenton oxidation of the refractory organics in the concentrates. The effectiveness of the E-Fenton treatment of the concentrates was appraised in terms of its removal efficiency of total organic carbon (TOC) of the concentrates. The effects of FeSO(4) dosage, current density, initial pH of the solution, and cathode area on the process performance were also evaluated. Under optimal reaction conditions that included a current density of 30 mA cm(-2), FeSO(4) dosage of 10mM, initial pH of 3, and cathode area of 20 cm(2), the TOC and total nitrogen (TN) removal efficiencies were 82% and 51% after 6h of the E-Fenton treatment. The results indicated that the E-Fenton technology could produce sufficient amounts of advanced oxidants in situ to effectively degrade the refractory organic pollutants in high-strength leachate concentrates.


Asunto(s)
Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Carbono/química , Electrodos , Compuestos Ferrosos/química , Peróxido de Hidrógeno/química , Politetrafluoroetileno/química , Ultrafiltración
12.
Chem Commun (Camb) ; 46(22): 3872-4, 2010 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-20445936

RESUMEN

A new sensing approach, employing diffraction gratings of hydrogel functionalized with glucose oxidase (GOx), was developed for quantitative glucose detection.


Asunto(s)
Técnicas Biosensibles/métodos , Glucosa Oxidasa/química , Glucosa/análisis , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Resinas Acrílicas/química , Enzimas Inmovilizadas/química , Temperatura
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