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1.
Artículo en Inglés | MEDLINE | ID: mdl-38739731

RESUMEN

CONTEXT: Both physical activity (PA) and sedentary behavior (SB) exert important impact on type 2 diabetes, but it remains unclear how maximum impact on improving the mortality and optimized proportion of the two lifestyles combination exists. OBJECTIVE: To explore the impacts of PA/SB combinations on mortality in patients with diabetes. METHODS: Patients with type 2 diabetes patients samplings were collected from the National Health and Nutrition Examination Survey (NHANES) dataset. Their lifestyles were categorized into eight groups based on combinations of the PA and SB levels. Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals. RESULTS: During the follow-up period, 1,148 deaths (18.94%) were recorded. High SB (sedentary time ≥6 hours/day) was significantly associated with higher all-cause mortality (HR 1.65). In participants with low SB (<6 hours/day), low PA was associated with lower all-cause mortality (HR 0.43), while further increase of PA level did not show further reduction in either all-cause or cardiovascular mortality. In contrast, in participants with high SB,all levels of PA were associated with lower all-cause mortality (p<0.05), but only moderate PA was associated with lower cardiovascular mortality (HR 0.30). CONCLUSIONS: In patients with type 2 diabetes, different combinations of various levels of PA and SB are associated with different degree of risk for all-cause or cardiovascular mortality.

2.
Chempluschem ; : e202400190, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698501

RESUMEN

Chemical recycling and upcycling offer promising approaches for the management of plastic wastes. Hydrodeoxygenation (HDO) is one of the appealing ways for conversion of oxygen-containing plastic wastes, including polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polycarbonate (PC), polyphenyl ether (PPO), and polyether ether ketone (PEEK), into cyclic alkanes and aromatics in high yields under mild reaction conditions. The challenge lies in achieving C-O activation while preserving C-C bonds. In this review, we highlight the recent advancements in catalytic strategies and catalysts for the conversion of these oxygen-containing plastic wastes into cycloalkanes and aromatics. The reaction systems, including multi-step routes, direct HDO and transfer HDO methods, are exemplified. The design and performance of HDO catalysts are systematically summarized and compared. We comprehensively discuss the functions of the catalysts' components, reaction pathway and mechanism to gain insights into the HDO process for efficient valorization of oxygen-containing plastic wastes. Finally, we provide perspectives for this field, with specific emphasis on the non-noble metal catalyst design, selectivity control, reaction network and mechanism studies, mixed plastic wastes management and product functionalization. We anticipate that this review will inspire innovations on the catalytic process development and rational catalyst design for the HDO of oxygen-containing aromatic plastics to establish a low-emission circular economy.

3.
Water Res ; 245: 120618, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37716297

RESUMEN

The bio-cake layer is one of the most negative effects during water and wastewater filtration, but its potential behoof of biodegradation is poorly understood. In this study, we activated and reconstructed the bio-cake by using the carbon nanotube membrane (25 cm2 area, 17 LMH flux) as the anode in an anaerobic membrane bioreactor (AnMBR), and investigated its positive role in advanced removal of dissolved organic matter from up-flow anaerobic sludge bed unit (3 L/d) when treating synthetic municipal wastewater. At the anodic membrane interface, the enhanced biodegradation was proved to dominate the DOM reduction (contribution >40%), controlling the effluent COD as low as 19.2 ± 2.5 mg/L. Bio-cake characterizations suggested that the positive potential induced electroactive improvement, cell viability boost, and metabolic optimization. Metatranscriptomic analyses revealed that anode respiratory out-compete methanogenesis, forwarding a synergetic metabolism between enriched fermenters like Proteiniphilum sp. and exoelectrogens like Geobacter sp. Thus, electroactive bio-cake not only accelerated the decomposition of inside foulants to maintain the high flux, but also efficiently intercepted flow-through DOM due to reduced mass-transfer limitations and enhanced metabolic activity. An ordered, non-clogging, and potentially functional "cell filter" was established to achieve a win-win situation between fouling control and effluent improvement, which is promising to upgrade the AnMBR technology for maximizing the sustainable regeneration in future wastewater treatment.

4.
Angew Chem Int Ed Engl ; 62(46): e202310505, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37534570

RESUMEN

To address the global plastic pollution issues and the challenges of hydrogen storage and transportation, we report a system, based on the hydrodeoxygenation (HDO) of oxygen-containing aromatic plastic wastes, from which organic hydrogen carriers (LOHCs) can be derived. We developed a catalytic system comprised of Ru-ReOx /SiO2 +HZSM-5 for direct HDO of polycarbonate (PC), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyphenylene oxide (PPO), and their mixtures, to cycloalkanes as LOHCs, with high yields up to 99 %, under mild reaction conditions. The theoretical hydrogen storage capacity reaches ca. 5.74 wt%. The reaction pathway involves depolymerization of PC into C15 aromatics and C15 monophenols by direct hydrogenolysis of the C-O bond between the benzene ring and ester group, and subsequent parallel hydrogenation of C15 aromatics and HDO of C15 monophenols. HDO of cyclic alcohol is the rate-determining step. The active site is Ru metallic nanoparticles with partially covered ReOx species. The excellent performance is attributed to the synergetic effect of oxophilic ReOx species and Ru metallic sites for C-O hydrogenolysis and hydrogenation, and the promotion effect of HZSM-5 for dehydration of cyclic alcohol. The highly efficient and stable dehydrogenation of cycloalkanes over Pt/γ-Al2 O3 confirms that HDO products can act as LOHCs.

6.
J Alzheimers Dis ; 94(1): 115-136, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37248897

RESUMEN

BACKGROUND: There is limited information about gene-environment interaction on the occurrence and the progression of Alzheimer's disease. OBJECTIVE: To explore the effect of environmental low-dose cadmium (Cd) exposure on the progress of Alzheimer's disease and the underlining mechanism. METHODS: We administered 1 mg/L, 10 mg/L cadmium chloride (treated groups), and water (control group) to C57BL/6J and APP/PS1 mice through drinking water, from one week before mating, until the offspring were sacrificed at 6 months of age. The behaviors, Cd level, blood-brain barrier (BBB) leakage, Aß1-42 deposition, and inflammation expression were evaluated in these mice. RESULTS: Mice of both genotypes had similar blood Cd levels after exposure to the same dose of Cd. The toxic effects of Cd on the two genotypes differed little in terms of neuronal histomorphology and BBB permeability. Cd caused a series of pathological morphological changes in the mouse brains and more fluorescent dye leakage at higher doses. Furthermore, the APP/PS1 mice had more severe damage than the C57BL/6J mice, based on the following five criteria. They were increasing anxiety-like behavior and chaos movement, spatial reference memory damage, Aß plaque deposition in mouse brains, increasing microglia expression in the brain, and IL-6 higher expression in the cortex and in the serum. CONCLUSION: Low-dose Cd exposure for 6 months increases Aß plaque deposition and BBB permeability, exacerbates inflammatory responses, and activates microglia, in APP/PS1 mice. APP/PS1 gene-environmental Cd interaction aggravates the progression of Alzheimer's disease in mice.


Asunto(s)
Enfermedad de Alzheimer , Ratones , Animales , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Cadmio/toxicidad , Barrera Hematoencefálica/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Ratones Transgénicos , Ratones Endogámicos C57BL , Péptidos beta-Amiloides/metabolismo , Inflamación/inducido químicamente , Inflamación/patología , Modelos Animales de Enfermedad , Presenilina-1/genética , Presenilina-1/metabolismo
8.
J Environ Manage ; 339: 117933, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37080099

RESUMEN

Sewage sludge (SS) has been extensively used as an alternative fertilizer in forest plantations, which are beneficial in supplying timbers and mitigating climate change. However, whether the extra nitrogen (N) applied by SS would enhance the soil nitrous oxide (N2O) emission, an important greenhouse gas, in forest plantations have not been well understood. The objective of this study is to evaluate the ecological effects of SS application on soils, by investigating the soil N2O emission and the toxicity of the potentially toxic elements (PTEs) in soil. A field fertilization experiment was conducted in Eucalyptus plantations with four fertilization rates (0 kg m-2, 1.5 kg m-2, 3.0 kg m-2, and 4.5 kg m-2). The soil N2O emissions were monitored at a soil depth of 0-10 cm using static chamber method, soil chemical properties, and PTEs were determined at soil depths of 0-10 cm, 10-20 cm, and 20-40 cm. The average soil N2O emission rate was 8.1 µg N2O-N h-1 m-2 in plots without SS application (control). The application of SS significantly increased the soil N2O emissions by 7-10 times as to control. The increased N2O emissions were positively related to the soil total phosphorus and nitrogen and negatively correlated with copper and zinc, which increased with the SS application. However, the potential ecological risk index (Ei) and the comprehensive potential ecological risk index (RI) of PTEs were lower than 40 and 150 respectively, which indicating a low toxicity of PTEs to soil health. After seven months of SS application, the priming effects of SS on soil N2O emissions gradually diminished. These findings suggest that the application of SS may increase N2O emissions at the initial stages of application (<7 months) and may have a low PTEs pollution risk, even at a high SS addition rate (4.5 kg m-2).


Asunto(s)
Eucalyptus , Metales Pesados , Suelo/química , Aguas del Alcantarillado , Nitrógeno/análisis , Fertilizantes/análisis , Óxido Nitroso/análisis , Agricultura , China
9.
Respir Res ; 24(1): 8, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36627645

RESUMEN

BACKGROUND: Lung fibroblast activation is associated with airway remodeling during asthma progression. Stearoyl-CoA desaturase 1 (SCD1) plays an important role in the response of fibroblasts to growth factors. This study aimed to explore the effects of SCD1 on fibroblast activation induced by transforming growth factor-ß1 (TGF-ß1) and the role of the phosphatidylinositol-3-kinase-AKT serine-threonine protein kinase-mechanistic target of rapamycin (PI3K-Akt-mTOR) pathway on the regulation of SCD1 expression in airway remodeling. METHODS: Female C57BL/6 mice were sensitized and challenged with house dust mites to generate a chronic asthma model. The inhibitor of SCD1 was injected i.g. before each challenge. The airway hyper-responsiveness to methacholine was evaluated, and airway remodeling and airway inflammation were assessed by histology. The effects of SCD1 on fibroblast activation were evaluated in vitro using an SCD1 inhibitor and oleic acid and via the knockdown of SCD1. The involvement of the PI3K-Akt-mTOR-sterol regulatory element-binding protein 1 (SREBP1) pathway in lung fibroblasts was investigated using relevant inhibitors. RESULTS: The expression of SCD1 was increased in fibroblasts exposed to TGF-ß1. The inhibition of SCD1 markedly ameliorated airway remodeling and lung fibroblast activation in peripheral airways. The knockdown or inhibition of SCD1 resulted in significantly reduced extracellular matrix production in TGF-ß1-treated fibroblasts, but this effect was reversed by the addition of exogenous oleic acid. The PI3K-Akt-mTOR-SREBP1 pathway was found to be involved in the regulation of SCD1 expression and lung fibroblast activation. CONCLUSIONS: The data obtained in this study indicate that SCD1 expression contributes to fibroblast activation and airway remodeling and that the inhibition of SCD1 may be a therapeutic strategy for airway remodeling in asthma.


Asunto(s)
Asma , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Femenino , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Ácido Oléico/farmacología , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/farmacología , Remodelación de las Vías Aéreas (Respiratorias) , Ratones Endogámicos C57BL , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Pulmón/metabolismo , Asma/patología , Fibroblastos/metabolismo , Sirolimus/farmacología , Estearoil-CoA Desaturasa/genética , Estearoil-CoA Desaturasa/metabolismo
10.
Adv Mater ; 35(27): e2102427, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34665482

RESUMEN

Topological insulators (TIs) provide intriguing prospects for the future of spintronics due to their large spin-orbit coupling and dissipationless, counter-propagating conduction channels in the surface state. The combination of topological properties and magnetic order can lead to new quantum states including the quantum anomalous Hall effect that was first experimentally realized in Cr-doped (Bi,Sb)2 Te3 films. Since magnetic doping can introduce detrimental effects, requiring very low operational temperatures, alternative approaches are explored. Proximity coupling to magnetically ordered systems is an obvious option, with the prospect to raise the temperature for observing the various quantum effects. Here, an overview of proximity coupling and interfacial effects in TI heterostructures is presented, which provides a versatile materials platform for tuning the magnetic and topological properties of these exciting materials. An introduction is first given to the heterostructure growth by molecular beam epitaxy and suitable structural, electronic, and magnetic characterization techniques. Going beyond transition-metal-doped and undoped TI heterostructures, examples of heterostructures are discussed, including rare-earth-doped TIs, magnetic insulators, and antiferromagnets, which lead to exotic phenomena such as skyrmions and exchange bias. Finally, an outlook on novel heterostructures such as intrinsic magnetic TIs and systems including 2D materials is given.

11.
ACS Meas Sci Au ; 2(6): 629-640, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36573076

RESUMEN

Bead-based immunoassays are multiparametric analysis allowing for the simultaneous quantification of a large number of biomarkers within a single sample. Mass cytometry is an emerging cytometric technique that offers a high multiplexing capacity in a high-throughput setting but has not yet been applied to bead-based assays. In this study, we developed a multiplex bead-based immunoassay of cytokines and CD163 designed for mass cytometry (MC). A set of 11 types of lanthanide-encoded microbeads were synthesized by two-stage dispersion polymerization as classifier candidates for the assay. These beads were then decorated with different Abs on the surface to capture the target cytokines in solution. Gold nanoparticles were employed as reporters to identify the binding of target cytokines on the classifier surface. As a proof-of-concept study, we first developed four-plex and nine-plex assays of mixtures of cytokines in standard solutions. The MC signal intensities of these immunoassays were responsive to the concentration differences in the standard solutions with high detection sensitivities at low analyte concentrations. Finally, we examined a sample of peripheral blood mononuclear cells (PBMCs) with the nine-plex assay, comparing an unstimulated sample with a sample stimulated to promote cytokine secretion.

12.
BMC Pulm Med ; 22(1): 333, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36056339

RESUMEN

BACKGROUND: Human tumors are highly heterogeneous at the cellular, molecular, genetic and functional levels. Tumor heterogeneity has tremendous impact on cancer progression and treatment responses. However, the mechanisms for tumor heterogeneity have been poorly understood due to the lack of experimental models. METHODS: This study provides a novel exploration and analysis of the impacts of cellular and molecular heterogeneity of human lung epithelial cells on their malignant transformation following chronic exposure to cigarette smoke extracts. RESULTS: The ability of cigarette smoke extract (CSE) to cause malignant transformation of the human bronchial epithelial cells (16HBE) is dependent on the sizes of the cells. Epithelial-mesenchymal transition (EMT) plays an important role in this process. Mechanistically, CSE-induced malignant transformation of 16HBE cells was closely linked to the reduced relative telomere length of the larger 16HBE cells, thereby up-regulation of the expression of stemness genes. CONCLUSIONS: These findings provide novel insights for understanding the impact of cellular heterogeneity in lung cancer development. The in vitro transformation model described in this study could be extrapolated to studying the pathogenesis of other malignancies, as well as for mechanistic studies that are not feasible in vivo.


Asunto(s)
Fumar Cigarrillos , Neoplasias Pulmonares , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Fumar Cigarrillos/efectos adversos , Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal , Humanos , Neoplasias Pulmonares/genética , Nicotiana/efectos adversos
13.
Front Public Health ; 10: 883566, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35419339

RESUMEN

Population aging is getting enlarged in the upcoming decades. Meanwhile, old-aged longevity and dependency are getting large due to improvement in life expectancy. In literature, it is claimed that old-aged dependency affects the wellbeing of society. Thus, the study intends to explore the impact of population aging on human wellbeing. The study adopts the Autoregressive Distributed Lag (ARDL) approach for empirical analysis by using time-series series data from 1990 to 2020. The study findings reveal that an increase in population aging reports a significant and decreasing impact on human wellbeing. However, an increase in health expenditure reports a significant and increasing impact on human wellbeing. Thus, China must pay attention to population aging to improve human health.


Asunto(s)
Envejecimiento , Esperanza de Vida , Anciano , China/epidemiología , Gastos en Salud , Humanos , Persona de Mediana Edad , Factores de Tiempo
14.
Respir Res ; 23(1): 75, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35351157

RESUMEN

BACKGROUND: Up-regulation of aerobic glycolysis has been reported as a characterization of asthma and facilitates airway inflammation. We has been previously reported that short isoform thymic stromal lymphopoietin (sTSLP) could reduce inflammation in asthmatic airway epithelial cells. Here we wanted to investigate whether the inhibition of sTSLP on asthma is related to aerobic glycolysis. METHODS: Asthmatic model was established in challenging Male BALB/c mice and 16-HBE (human bronchial epithelial) cell line with house dust mite (HDM). Indicators of glycolysis were assessed to measure whether involve in sTSLP regulating airway epithelial cells inflammation in asthmatic model in vivo and in vitro. RESULTS: sTSLP decreased inflammation of asthmatic airway and aerobic glycolysis in mice. HDM or long isoform thymic stromal lymphopoietin (lTSLP) promoted HIF-1α expression and aerobic glycolysis by miR-223 to target and inhibit VHL (von Hippel-Lindau) expression 16-HBE. Inhibition of aerobic glycolysis restrained HDM- and lTSLP-induced inflammatory cytokines production. sTSLP along had almost no potential to alter aerobic glycolysis of 16-HBE. But sTSLP decreased LDHA (lactate dehydrogenase A) and LD (Lactic acid) levels in BALF, and HIF-1α and LDHA protein levels in airway epithelial cells of asthma mice model. lTSLP and sTSLP both induced formation of TSLPR and IL-7R receptor complex, and lTSLP obviously facilitated phosphorylation of JAK1, JAK2 and STAT5, while sTSLP induced a little phosphorylation of JAK1 and STAT5. CONCLUSION: We identified a novel mechanism that lTSLP could promote inflammatory cytokines production by miR-223/VHL/HIF-1α pathway to upregulate aerobic glycolysis in airway epithelial cells in asthma. This pathway is suppressed by sTSLP through occupying binding site of lTSLP in TSLPR and IL-7R receptor complex.


Asunto(s)
Asma , Citocinas , Animales , Asma/metabolismo , Citocinas/metabolismo , Epitelio/metabolismo , Glucólisis , Humanos , Inflamación/metabolismo , Masculino , Ratones , Isoformas de Proteínas , Linfopoyetina del Estroma Tímico
15.
Am J Respir Cell Mol Biol ; 66(6): 648-660, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35358396

RESUMEN

Thymic stromal lymphopoietin presents in two distinct isoforms: short-form (sfTSLP) and long-form (lfTSLP). lfTSLP promotes inflammation, whereas sfTSLP inhibits inflammation, in allergic asthma. However, little is known about the regulation of lfTSLP and sfTSLP during allergic attack in the asthma airway epithelium. Here, we report that small ubiquitin-like modifier (SUMOylation) was enhanced in house dust mite-induced allergic asthma airway epithelium. Inhibition of SUMOylation significantly alleviated airway T-helper cell type 2 inflammation and lfTSLP expression. Mechanistically, chromobox 4 (CBX4), a SUMOylation E3 ligase, enhanced lfTSLP mRNA translation, but not sfTSLP, through the RNA-binding protein muscle excess (MEX)-3B. MEX-3B promoted lfTSLP translation by binding the lfTSLP mRNA through its K homology domains. Furthermore, CBX4 regulated MEX-3B transcription in human bronchial epithelial cells through enhancing SUMOylation concentrations of the transcription factor TFII-I. In conclusion, we demonstrate an important mechanism whereby CBX4 promotes MEX-3B transcription through enhancing TFII-I SUMOylation and MEX-3B enhances the expression of lfTSLP through binding to the lfTSLP mRNA and promoting its translation. Our findings uncover a novel target of CBX4 for therapeutic agents for lfTSLP-mediated asthma.


Asunto(s)
Asma , Citocinas , Ligasas , Proteínas del Grupo Polycomb , Pyroglyphidae , Sumoilación , Animales , Asma/inmunología , Asma/metabolismo , Citocinas/metabolismo , Humanos , Inflamación , Ligasas/metabolismo , Proteínas del Grupo Polycomb/metabolismo , Pyroglyphidae/inmunología , ARN Mensajero/metabolismo , Linfopoyetina del Estroma Tímico
16.
Front Pharmacol ; 13: 795934, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35222024

RESUMEN

Avasimibe (Ava) is an acetyl-CoA acetyltransferase 1 (ACAT1) specific inhibitor and an established medicine for atherosclerosis, owing to its excellent and safe anti-inflammation effects in humans. However, its efficacy in asthma has not yet been reported. We first administered varying concentrations of avasimibe to house dust mite (HDM)-induced asthmatic mice; results showed that 20 mg/kg avasimibe most significantly reduced IL-4 and IL-5 production in bronchoalveolar lavage fluid (BALF) and total IgE in serum, and the avasimibe treatment also exhibited lower mucus secretion, decreased goblet and basal cells but increased ciliated cells compared to the HDM group. And the redistribution of adherens junction (AJ) proteins induced by HDM was far more less upon avasimibe administration. However, avasimibe did not reduce the cholesterol ester ratio in lung tissues or intracellular cholesterol ester, which is avasimibe's main effect. Further analysis confirmed that avasimibe impaired epithelial basal cell proliferation independent of regulating cholesterol metabolism and we analyzed datasets using the Gene Expression Omnibus (GEO) database and then found that the KRT5 gene (basal cell marker) expression is correlated with the ß-catenin gene. Moreover, we found that ß-catenin localized in cytomembrane upon avasimibe treatment. Avasimibe also reduced ß-catenin phosphorylation in the cytoplasm and inactivated the Wnt/ß-catenin signaling pathway induced by HDMs, thereby alleviating the airway epithelial barrier disruption. Taken together, these findings indicated that avasimibe has potential as a new therapeutic option for allergic asthma.

17.
Water Res ; 212: 118123, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35121418

RESUMEN

Excessive ammonia has an inhibitory effect on anaerobic granular sludge (AnGS) when treating industrial wastewater with high concentration of ammonia and organic matters. The addition of conductive materials has been widely reported to improve the AnGS activity, which has the potential to alleviate the ammonia inhibition. In this study, the addition of magnetite was carried out to enhance the activity of AnGS in UASB reactor, then the response of AnGS to different ammonia levels was investigated. Results showed that magnetite facilitated the enrichment of Methanosaeta and Clostridium sensu stricto 1. Under the ammonia stress (up to 5 g TAN/L), it was interesting that Methanosaeta was better retained (abundance of 45.8%), and the abundance of ammonia-resistant Clostridium sensu stricto 1 increased to 34.3% in presence of magnetite. RT-qPCR analysis revealed that Methanosaeta could maintain metabolically active for counteracting the ammonia inhibition along with the higher transcription of genes encoding for CO2-dependent pathway. The electron transport activity and ATP content of AnGS were 1.25-2.12 and 1.23-2.56 folds higher than those in the control group, respectively. In addition, the AnGS could maintain the stability of structure because Methanosaeta was the skeleton of AnGS. As a result, the analysis of enzyme activity showed that the overall methanogenic metabolism was more active, thus ensured the effective operation of UASB reactor. This study provided the scientific understanding about the role of magnetite to alleviate the ammonia inhibition, and had important implications for stable treatment and recycling of industrial wastewater.


Asunto(s)
Amoníaco , Óxido Ferrosoférrico , Anaerobiosis , Reactores Biológicos , Metano , Aguas del Alcantarillado
18.
Langmuir ; 38(8): 2525-2537, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35167296

RESUMEN

Lanthanide nanoparticles (LnNPs) have the potential to be used as high-sensitivity mass tag reporters in mass cytometry immunoassays. For this application, however, the LnNPs must be made colloidally stable in aqueous buffers, demonstrate minimal non-specific binding to cells, and have functional groups to attach antibodies or other targeting agents. One possible approach to address these requirements is by using lipid coating to modify the surface of the LnNPs. In this work, 39 nm diameter NaYF4:Yb, Er NPs (LnNPs) were coated with a lipid formulation consisting of egg sphingomyelin, 1,2-dioleoyl-sn-glycero-3-phosphocholine, 1,2-dioleoyl-3-trimethylammonium propane, cholesterol-(polyethylene glycol-600), and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[biotinyl(polyethylene glycol)-2000]. The resulting biotinylated lipid-coated LnNPs were characterized by dynamic light scattering to determine the hydrodynamic size and stability in phosphate buffered saline, and the composition of the lipid coatings was quantified by liquid chromatography-tandem mass spectrometry. The specific and non-specific binding of the biotinylated lipid-coated LnNPs to a model system of functionalized polystyrene microbeads were then tested by both suspension and imaging mass cytometry. We found that targeted binding with minimal non-specific binding can be achieved with the lipid-coated LnNPs and that the lipid composition of the coating has an impact on the performance of the LnNPs as mass cytometry reporters. These results additionally establish the importance of quantifying the composition of lipid-coated nanomaterials to optimize them more effectively for their desired application.


Asunto(s)
Elementos de la Serie de los Lantanoides , Nanopartículas del Metal , Nanopartículas , Citometría de Imagen , Nanopartículas/química , Fosfatidiletanolaminas/química , Suspensiones
19.
Langmuir ; 37(27): 8240-8252, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34170710

RESUMEN

Bead-based assays in flow cytometry are multiplexed analytical techniques that allow rapid and simultaneous detection and quantification of a large number of analytes from small volumes of samples. The development of corresponding bead-based assays in mass cytometry (MC) is highly desirable since it could increase the number of analytes detected in a single assay. The microbeads for these assays have to be labeled with metal isotopes for MC detection. One must also be able to functionalize the bead surface with affinity reagents to capture the analytes. Metal-encoded polystyrene microbeads prepared by multi-stage dispersion polymerization can produce effective isotopic signals in MC with relatively small bead-to-bead variations. However, functionalizing this microbead surface with bioaffinity agents remains challenging, possibly due to the interference of the steric-stabilizing PVP corona on the microbead surface. Here, we report a systematic investigation of a silica coating approach to coat Eu-encoded microbeads with thin silica shells, to functionalize the surface with amino groups, and to introduce bioaffinity agents. We examine the effect of silica shell roughness on the bioconjugation capacity and the effect of silica shell thickness on signal quality in MC measurements. To limit non-specific binding, we converted the amino groups on the microbead surface to carboxylic acid groups. Antibodies were effectively attached to microbead by first conjugating NeutrAvidin to the carboxyl-modified bead surface and then attaching biotinylated antibodies to the NeutrAvidin-modified bead surface. The antibody-modified microbeads can specifically capture antigens, which were marked with isotopic labels, and generate strong signals in MC. These are promising results for the development of bead-based assays in MC.


Asunto(s)
Poliestirenos , Dióxido de Silicio , Anticuerpos , Citometría de Flujo , Microesferas
20.
Environ Sci Technol ; 55(2): 1004-1014, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33356195

RESUMEN

The rapid emergence of antibiotic resistance genes (ARGs) has become an increasingly serious threat to public health. Previous studies illustrate the antibiotic-like effect of many substances. However, whether and how commonly used or existing non-antibiotic metalloids (e.g., selenate) would enhance ARG spread remains poorly known. Here, we tracked the long-term operation of a bioreactor continuously fed with selenate for more than 1000 days. Metagenomic sequencing identified 191 different ARGs, of which the total abundance increased significantly after the amendment of selenate. Network analyses showed that ARGs resisting multiple drugs had very similar co-occurrence patterns, implying a potentially larger health risk. Host classification not only indicated multidrug-resistant species but also distinguished the mechanism of ARG enrichment for vertical transfer and horizontal gene transfer. Genome reconstruction of an ARG host suggested that selenate and its bioreduction product selenite could stimulate the overproduction of intracellular reactive oxygen species, which was confirmed by the direct measurement. Bacterial membrane permeability, type IV pilus formation, and DNA repair and recombination were also enhanced, together facilitating the horizontal acquirement of ARGs. Overall, this study for the first time highlights the ARG emergence and dissemination induced by a non-antibiotic metalloid and identifies ARG as a factor to consider in selenate bioremediation.


Asunto(s)
Antibacterianos , Metaloides , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Ácido Selénico
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