Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 9.925
Filtrar
1.
Perfusion ; : 2676591211041945, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34524052

RESUMO

BACKGROUND: The Monocyte to high density lipoprotein ratio (MHR) has been postulated as a novel parameter associated with adverse renal and cardiovascular outcomes. In this study we investigated the association of MHR with cardiac surgery-associated acute kidney injury (CSA-AKI). METHODS: In this retrospective study, we analyzed the data pertaining to 1505 patients undergoing cardiopulmonary bypass (CPB) surgery. The CSA-AKI, which was defined using Kidney Disease Improving Global Outcomes criteria. Concurrently, a retrospective scan of patient files was conducted and information relevant to nephropathy such as the level of their serum creatinine (SCr), Blood urea nitrogen (BUN), uric acid (UA), serum cystatin C (Cys-C), total cholesterol (TC), triglycerides (TG), glucose and MHR, ejection fraction, CPB duration time, and other indicators. RESULTS: About 1505 patients were studied of whom 195 developed AKI. MHR was significantly higher in the AKI patients (p = 0.001). In multivariate logistic regression analysis, MHR, UA, Cys-C, age, glucose, and history of chronic kidney disease or hypertension were independently correlated with CSA-AKI. CONCLUSIONS: As a laboratory index, the elevated MHR is convenient, independent, and a useful predictor for CSA-AKI.

2.
J Mater Chem B ; 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34491255

RESUMO

Osteoarticular Tuberculosis (TB) is a challenging issue because of its chronicity and recurrence. Many drug delivery systems (DDSs) have been developed for general chemotherapy. Herein, we take advantage of instant hydrogelation to in situ encapsulate drugs onto implants intraoperatively, optimizing the drug release profile against osteoarticular TB. First-line chemodrugs, i.e. rifampicin (RFP) and isoniazid (INH) are firstly loaded on tricalcium phosphate (TCP). Then, the encapsulating hydrogel is fabricated by dipping in chitosan (CS) and ß-glycerophosphate (ß-GP) solution and heating at 80 °C for 40 min. The hydrogel encapsulation inhibits explosive drug release initially, but maintains long-term drug release (INH, 158 days; RFP, 53 days) in vitro. Therefore, this technique could inhibit bone destruction and inflammation from TB effectively in vivo, better than our previous ex situ prepared DDSs. The encapsulating technology, i.e. instant hydrogelation of drug-loaded implants, shows potential for regulating the type and ratio of drugs, elastic and viscous modulus of the hydrogel according to the state of illness intraoperatively for optimal drug release.

3.
J Colloid Interface Sci ; 607(Pt 1): 68-75, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34492355

RESUMO

Metallic vanadium dichalcogenides with high conductivity and large layer spacing are fantastically potential to be cathode candidates for aqueous zinc ion batteries. However, simply reliance on the reversible Zn2+ intercalation/deintercalation process in the layer structure of vanadium dichalcogenides makes it suffer from low specific capacity and limited cycling number. Here we report a facile in-situ electrochemical oxidation strategy to boost the zinc ion storage capacity of interlayer-expanded vanadium disulfide (VS2·NH3) hollow spheres with satisfying cyclic stability. The hydrated vanadium oxide (V2O5·nH2O) generated from oxidized VS2·NH3, are endowed with reduced nanosheet size and subordinated porous structure, which provides abundant accessible sites and accelerates the zinc ion diffusion process. As a result, the VS2·NH3 derived cathode after the electrochemical oxidation process delivers a high reversible capacity of 392 mA h g-1 at 0.1 A g-1 and long cyclic stability (110% capacity retention at 3 A g-1 after 2000 cycles). The efficient oxidation process of VS2·NH3 cathode and the storage mechanism in the subsequent cycles are schematically investigated. This work not only reveals the zinc ion storage mechanism of the oxidized VS2·NH3 but also sheds light on advanced design for high-performance Zn ion cathode materials.

4.
Biomark Med ; 15(14): 1261-1270, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34488430

RESUMO

Background: This study explored the clinical role of lncRNA MEG3 in rheumatoid arthritis (RA) management. Materials & methods: Totally, 191 active RA patients were enrolled, and their lncRNA MEG3 expressions in peripheral blood monoclonal cells were detected. Results: LncRNA MEG3 expression was downregulated, and it negatively correlated with lesion joints, inflammation and disease activity in RA patients. Moreover, lncRNA MEG3 expression was increased during treatment; meanwhile its increment correlated with treatment response and remission. Conclusion: LncRNA MEG3 may serve as a potential biomarker for monitoring treatment efficacy in RA management.

5.
Int J Biol Macromol ; 190: 206-213, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34492243

RESUMO

Easy deactivation of free enzymes under non-native condition has become a stumbling block to the industrial application of biocatalysis. Natural deep eutectic solvent (NADES) has been exploited as a novel reaction medium for improving enzyme stability. The present work focused on preserving and enhancing the activity of carbonic anhydrase (CA) in a more economical and biocompatible NADES system. We synthesized six choline chloride/betaine-based NADES and analyzed the effects of compositions and concentrations of NADES on their physicochemical properties. The Bet-Gly (1: 2) NADES (55%) was proved to be more suitable as reaction medium for CA by analyzing enzyme activity in the presence of NADES. The enhancement in the stability of CA was found to be as a result of a three-dimensional hydrogen bonding network, rather than the individual or the synergistic effect of betaine and glyceride. The conformational change of CA to become more compact was confirmed both by fluorescence spectrum analysis and circular dichroism analysis. It is worth mentioning that a remarkable thermal stability was maintained when CA was incubated at temperature below 60 °C, and about 96% of activity was still restored in 55% NADES at 60 °C for 12 h.

6.
Environ Int ; 157: 106860, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34500363

RESUMO

Electronic waste (e-waste) is a well-known source of plastic additives in the environment. However, the e-waste-related occupational exposure to organophosphite antioxidants (OPAs) and the relevant oxidation products-novel organophosphate esters (NOPEs)-via different pathways is still unknown. In this study, six OPAs and three NOPEs were measured in 116 dust and 43 hand-wipe samples from an e-waste dismantling area in Central China. The median concentrations of ΣOPAs and ΣNOPEs were 188 and 13,900 ng·g-1 in workshop dust and 5,250 ng·m-2 and 53,600 ng·m-2 on workers' hands, respectively. The increasing concentrations of dust in the form of triphenyl phosphate (TPHP) (p < 0.01) and tris(2,4-di-tert-butylphenyl) phosphate (AO168 = O) (p < 0.05) were strongly associated with the corresponding concentration on workers' hands. Furthermore, men had significantly lower levels of NOPEs on their hands than did women (p < 0.01). Moreover, the hand wipe levels of AO168 = O (41,600 ng·m-2) was significantly higher than that of the typical OPE (TPHP, 7370 ng·m-2), and the hand-to-mouth contact (ΣOPAs, 9.48 ng·kg bw-1·day-1; ΣNOPEs, 109 ng·kg bw-1·day-1) was a more significant and integrated pathway than dust ingestion (ΣOPAs, 0.10 ng·kg bw-1·day-1; ΣNOPEs, 5.01 ng·kg bw-1·day-1) of e-waste related occupational exposure to these "new" chemicals.

7.
J Hazard Mater ; 423(Pt A): 127043, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34479084

RESUMO

Bioremediation by phosphate-solubilizing bacteria (PSB) has attracted extensive attentions due to its economical and eco-friendly properties for lead (Pb) passivation in soil. Herein, bone char (BC) supported biochemical composite (CFB1-P) carrying advantages of BC, PSB, iron sulfide (FeS) and carboxymethyl cellulose (CMC) was designed and applied to Pb passivation. The composite at a mass ratio of BC:CMC:FeS = 1:1:1 possessed high passivation efficiency (65.47%), and has been demonstrated to offer appropriate habitat environment for PSB to defend against Pb(II) toxicity, thus enhancing the phosphate-solubilizing amount of PSB to 140.72 mg/L for passivating Pb(II). Batch experiments showed that the CFB1-P possessed excellent adsorption properties with maximal monolayer Pb(II) uptake of 452.99 mg/g during an extensive pH range of 2.0-6.0. Furthermore, by applying CFB1-P dosage of 3% into Pb-contaminated soil, the labile Pb fractions were reduced from 29.05% to 6.47% after simulated remediation of 10 days, and converted into steady fractions. The CFB1-P was demonstrated to achieve high Pb(II) passivation through combined functions of chemical precipitation, complexation, electrostatic attraction and biomineralization, accompanied by the formation of more stable crystal structures, for instance, Pb5(PO4)3OH, Pb3(PO4)2 and PbS. These results suggested CFB1-P as a potential alternative for efficient remediation of Pb-contaminated soil.

8.
J Hazard Mater ; 423(Pt A): 127025, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34481391

RESUMO

Municipal solid waste incineration (MSWI) fly ash is a typical hazardous waste worldwide. In this study, an innovative magnesium oxysulfate cement (MOSC) binder was designed for stabilization/solidification (S/S) of MSWI fly ash, focusing on the interactions between MOSC binder and typical metallic cations (Pb2+)/oxyanions (AsO33-). Experimental results showed that Pb and As slightly inhibited the reaction of high-sulfate 5MS system but significantly suppressed the reaction process of low-sulfate 10MS system. The 5MS binder system exhibited excellent immobilization efficiencies (99.8%) for both Pb and As. The extended X-ray absorption fine structure spectra suggested that Pb2+ coordinated with SO42-/OH- in the MOSC system and substituted Mg2+ ion sites in the internal structure of 5Mg(OH)2·MgSO4.7H2O (5-1-7) phase. In contrast, the AsO33- substituted SO42- sites with the formation of inner-sphere complexes with Mg2+ in the large interlayer space of the 5-1-7 structure. Subsequent MSWI fly ash S/S experiments showed that a small amount of reactive Si in MSWI fly ash interfered with the MOSC reaction and adversely influenced the immobilization efficiencies of Pb, As, and other elements. Through the use of 33 wt% tailored MOSC binder for MSWI fly ash treatment, a satisfying S/S performance could be achieved.

9.
J Hazard Mater ; 423(Pt A): 127079, 2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34488102

RESUMO

Sorption/desorption of two organic compounds (OCs), phenanthrene (PHE), and 1-nitronaphthalene (1-Nnap) on three polar and one nonpolar polypropylene (PP) microplastics (MPs) and earthworm bioaccumulation of MP associated PHE were systematically studied. Poly-butylene succinate (PBS) with the lowest glass transition temperature (Tg) showed the highest sorption toward PHE and 1-Nnap (Kd: 25,639 ± 276 and 1673 ± 28.8 L kg-1, respectively), while polylactic acid (PLA) with the highest Tg showed the least sorption (182 ± 5 and near 0), confirming that hydrophobic partition was the main driving force of sorption. However, polar interactions also contributed to the preferential sorption of 1-Nnap on polar poly-hydroxyalkanoates (PHA). Moreover, small particle size favored the sorption of MPs and simulated weathering enhanced sorption on MPs with medium/high Tg. As for desorption, slight hysteresis was observed in most cases with near-zero hysteresis index (HI), and PHE generally had higher HI than 1-Nnap. The simulated digestive solution could further promote the desorption of PHE. The PHE concentrations in earthworms with the presence of 5% PBS or PP MPs in soil were 1.50-2.35 or 1.59-1.75 times that of the control without MPs; and PBS MPs with the smallest particle size showed the greatest enhancement. The results of this study confirmed that polar MPs could strongly but reversibly sorb both polar and nonpolar OCs and hence promote the bioaccumulation of OCs to soil organisms.

10.
J Biomater Sci Polym Ed ; : 1-15, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34491876

RESUMO

The bilayer nanofibrous membrane fabricated via electrospinning technique can be considered as an ideal structure for the treatment of chronic skin diseases and exudative wound dressings. Wound exudate would affect healing and increases the likelihood of infection at the same time. Therefore, it is essential to produce a kind of wound dressing with relatively high hygroscopicity which could absorb wound exudate and provide a relatively dry healing environment. Bilayer nanofibrous membranes of poly(L-lactide-co-ε-caprolactone)/tetracycline hydrochloride- polyethylene oxide/sodium alginate-zinc oxide (PLCL/TCH-PEO/SA-ZnO) with drug delivery potential were prepared by electrospinning for wound healing. Then, a cross-linking which involved soaking the samples in an aqueous solution containing strontium ions for 4 h were conducted. SEM images showed that membranes still maintained the peculiar nanofibrous structure. The spinning aid (PEO) used was removed in the cross-linked alginate without affecting the PLCL/TCH outer layer gave the membrane good mechanical properties and manageability. The hydrophilicity of the mats was tested to evaluate the ability of the bilayer membrane to absorb exudate from the wound. In vitro drug release suggested that antibacterial agents TCH could release continuously more than 10 days. The cross-linked fibrous membrane has improved mechanical properties and fluid repellency, thus representing a barrier to the external environment and effective wound protection. Consequently, the bilayer fibrous scaffold with good hygroscopicity and drug release properties would have wide applications prospects for the treatment of chronic skin diseases and exudative wound dressings.

11.
Proc Natl Acad Sci U S A ; 118(37)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34493658

RESUMO

Midlife blood pressure is associated with structural brain changes, cognitive decline, and dementia in late life. However, the relationship between early adulthood blood pressure exposure, brain structure and function, and cognitive performance in midlife is not known. A better understanding of these relationships in the preclinical stage may advance our mechanistic understanding of vascular contributions to late-life cognitive decline and dementia and may provide early therapeutic targets. To identify resting-state functional connectivity of executive control networks (ECNs), a group independent components analysis was performed of functional MRI scans of 600 individuals from the Coronary Artery Risk Development in Young Adults longitudinal cohort study, with cumulative systolic blood pressure (cSBP) measured at nine visits over the preceding 30 y. Dual regression analysis investigated performance-related connectivity of ECNs in 578 individuals (mean age 55.5 ± 3.6 y, 323 female, 243 Black) with data from the Stroop color-word task of executive function. Greater connectivity of a left ECN to the bilateral anterior gyrus rectus, right posterior orbitofrontal cortex, and nucleus accumbens was associated with better executive control performance on the Stroop. Mediation analyses showed that while the relationship between cSBP and Stroop performance was mediated by white matter hyperintensities (WMH), resting-state connectivity of the ECN mediated the relationship between WMH and executive function. Increased connectivity of the left ECN to regions involved in reward processing appears to compensate for the deleterious effects of WMH on executive function in individuals across the burden of cumulative systolic blood pressure exposure in midlife.

12.
BMC Bioinformatics ; 22(1): 430, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496745

RESUMO

BACKGROUND: Essential proteins have great impacts on cell survival and development, and played important roles in disease analysis and new drug design. However, since it is inefficient and costly to identify essential proteins by using biological experiments, then there is an urgent need for automated and accurate detection methods. In recent years, the recognition of essential proteins in protein interaction networks (PPI) has become a research hotspot, and many computational models for predicting essential proteins have been proposed successively. RESULTS: In order to achieve higher prediction performance, in this paper, a new prediction model called TGSO is proposed. In TGSO, a protein aggregation degree network is constructed first by adopting the node density measurement method for complex networks. And simultaneously, a protein co-expression interactive network is constructed by combining the gene expression information with the network connectivity, and a protein co-localization interaction network is constructed based on the subcellular localization data. And then, through integrating these three kinds of newly constructed networks, a comprehensive protein-protein interaction network will be obtained. Finally, based on the homology information, scores can be calculated out iteratively for different proteins, which can be utilized to estimate the importance of proteins effectively. Moreover, in order to evaluate the identification performance of TGSO, we have compared TGSO with 13 different latest competitive methods based on three kinds of yeast databases. And experimental results show that TGSO can achieve identification accuracies of 94%, 82% and 72% out of the top 1%, 5% and 10% candidate proteins respectively, which are to some degree superior to these state-of-the-art competitive models. CONCLUSIONS: We constructed a comprehensive interactive network based on multi-source data to reduce the noise and errors in the initial PPI, and combined with iterative methods to improve the accuracy of necessary protein prediction, and means that TGSO may be conducive to the future development of essential protein recognition as well.


Assuntos
Biologia Computacional , Mapas de Interação de Proteínas , Algoritmos , Mapeamento de Interação de Proteínas , Proteínas/genética , Proteínas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
13.
BMC Cancer ; 21(1): 1004, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496800

RESUMO

BACKGROUND: Dysregulation of long non-coding RNAs (lncRNAs) has been identified in ovarian cancer. However, the expression and biological functions of LINC00852 in ovarian cancer are not understood. METHODS: The expressions of LINC00852, miR-140-3p and AGTR1 mRNA in ovarian cancer tissues and cells were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay. Gain- and loss-of-function assays were performed to explore the biological functions of LINC00852 and miR-140-3p in the progression of ovarian cancer in vitro. The bindings between LINC00852 and miR-140-3p were confirmed by luciferase reporter gene assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay. RESULTS: We found that LINC00852 expression was significantly up-regulated in ovarian cancer tissues and cells, whereas miR-140-3p expression was significantly down-regulated in ovarian cancer tissues. Functionally, LINC00852 knockdown inhibited the viability, proliferation and invasion of ovarian cancer cells, and promoted the apoptosis of ovarian cancer cells. Further investigation showed that LINC00852 interacted with miR-140-3p, and miR-140-3p overexpression suppressed the viability, proliferation and invasion of ovarian cancer cells. In addition, miR-140-3p interacted with AGTR1 and negatively regulated its level in ovarian cancer cells. Mechanistically, we found that LINC00852 acted as a ceRNA of miR-140-3p to promote AGTR1 expression and activate MEK/ERK/STAT3 pathway. Finally, LINC00852 knockdown inhibited the growth and invasion ovarian cancer in vivo. CONCLUSION: LINC00852/miR-140-3p/AGTR1 is an important pathway to promote the proliferation and invasion of ovarian cancer.

14.
Drug Deliv ; 28(1): 1785-1794, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34470555

RESUMO

The probable nanotoxicity to human health and the environment is a significant challenge for the sustainable application of nanomaterials in medicine. The cytototoxical effect of succimer (meso-2,3-dimercaptosuccinic acid-DMSA) coated titanium dioxide (DMSA-TiO2) with cultured human aortic endothelial cells (HAoECs) was assessed in this investigation. Our findings have shown that DMSA-TiO2 can be accumulated in HAoECs and dispersed in a cytoplasm on the culture medium. DMSA-cytotoxicity TiO2 effects were dose-responsive, and the concentrations were of little toxicity, and MTT stain testing showed that they had only 0.02 mg ml-1. Meanwhile, the lactate dehydrogenase biomarker was not considerably more remarkable than the biomarker from untreated (control) cells (free DMSA-TiO2). Though, also without any apparent signs of cell damage, the endocrine functions for prostacyclin I-2 and endothelin-1 and the urea transporter functions were modified. In addition, in vitro endothelial tube development has been shown that HAoECs could induce angiogenesis even with small amounts of DMSA-TiO2 (0.01 and 0.02 mg ml-1). Further, we have examined the in vivo toxicity and biochemical parameter by animal model. Furthermore, in vivo assessments designated that the resulting DMSA-TiO2 presented synergistic activities of angiogenesis activity. Overall, these findings show the cytotoxicity of DMSA-TiO2 and could induce adverse effects on normal endothelial cells.

15.
Molecules ; 26(17)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34500800

RESUMO

Separating oxidized zinc minerals from flotation tailings is always a challenge. In this study, a flotation tailing from Wulagen zinc mine in China (Zn grade < 1%) was processed using froth flotation with combinations of amines (OPA 10, OPA 1214, OPA 13, DDA) and Na2S to study the effects of these amines on the zinc recovery as well as their interactions with other reagents, aiming to screen out a proper reagent scheme to improve zinc separation from extremely low-grade zinc flotation tailings. The results show that different amines led to different flotation performance, and the collectors were ranked as OPA 1214, OPA 13, OPA 10 and DDA in a decreasing order based on flotation collectivity and selectivity. An increase in the concentration of each collector increased the zinc recovery but reduced the concentrate zinc grade. Interactions were also observed between different amines and Na2S and Na2SiO3, and OPA 1214 outdid the others in saving the usage of both the Na2S and Na2SiO3. The measured adsorption of collector onto smithsonite was found to correlate well with flotation test results. It was concluded that hydrocarbon chains can be held accountable for the difference in the flotation performance with different amines. The longer the hydrocarbon chain, the stronger the hydrophobic association ability of amine, which is conducive to the selective amine adsorption onto sulfurized smithsonite particles and hence the smithsonite flotation.

16.
J Adv Nurs ; 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34514616

RESUMO

AIMS: To investigate research hotspots and trends in nursing education from 2014 to 2020, and provide references for researchers to understand the research status and developing trends in this field. DESIGN: A co-word analysis based on keywords. METHODS: Data were obtained from nursing education-related academic research articles that were retrieved through a literature search using PubMed during the period of 2014-2020. Keywords included in the analysis of literature were considered as the research objects. Bibliographic Item Co-occurrence Matrix Builder (BICOMB) was employed to extract high-frequency keywords and generate co-occurrence matrix, graphical clustering toolkit (gCLUTO) was used to perform cluster analysis, and SPSS 25.0 was used to perform strategic diagram analysis. RESULTS: Overall, 7857 articles were retrieved, from which 2679 keywords were obtained and 64 high-frequency keywords extracted. The results revealed seven hotspots in nursing education during the period of 2014-2020, which included research on: (i) continuing education in nursing, (ii) application and influence of the internet in nursing education, (iii) postgraduate nursing education, (iv) undergraduate nursing education and clinical quality training, (v) current development status and tendency of nursing education, (vi) nursing teaching methods and (vii) organization and management in nursing education. CONCLUSION: The seven research hotspots could reflect the publication trends in nursing education. By providing a co-word analysis-including cluster and strategic diagram analysis-an overall command of the latest hotspots can be depicted, and researchers conducting research in nursing education can have some hints. IMPACT: This study allows the development of future research on nursing education. Future researchers should explore the application of new network technologies in the process of nursing teaching, quality of postgraduate nursing education, innovative teaching methods as well as teaching strategies of improving students' clinical ability, current situation of economics and leadership in nursing education and ability of organization and management in undergraduate nursing education.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34467488

RESUMO

Though gold mines provide significant economic benefits to local governments, mining causes soil pollution by potentially toxic trace elements (PTEs) in mining areas, especially in the Qinghai-Tibet Plateau. Screening of native plant species from mining areas is now an effective, inexpensive, and eco-friendly method for the remediation of PTEs in situ. In the present study, we conducted experiments to assess the accumulation of As, Cd, Pb, and Zn in 12 native plant species growing on a typical gold mining area in the Qinghai-Tibet Plateau. Our results showed that rhizosphere soils have high soil organic matter content, high levels of As, and moderate levels of Cd. Geranium pylzowianum accumulated relatively higher As in its shoots and exhibited translocation factor (TF) higher than 1 for As (4.65), Cd (1.87), and Pb (1.36). Potentilla saundersiana had bioconcentration factor of shoot (BCF-S) higher than 1 for Cd (4.52) and Pb (1.70), whereas its TF was higher than 1 for As, Cd, Pb, and Zn. These plant species exhibit strong tolerance to these PTEs. Furthermore, Elymus nutans accumulated low levels of As, Cd, Pb, and Zn in their shoots and exhibited TF values lower than 1 for the four PTEs. Therefore, G. pylzowianum is a promising candidate for the in situ phytoextraction of As, and P. saundersiana can be used as an effective plant for Cd and Pb phytoextraction. E. nutans is better suited for the phytostabilisation of multiple PTEs. This work is of significant importance for screening native plant species that can provide a reference for phytoremediation of PTE-contaminated soils in this area or other place with similar climate, and has a good potential for developing PTE phytoremediation strategies at mining sites.

18.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120299, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34474221

RESUMO

The optical sensor with ratiometric and turn-off dual modes is constructed to detect H2O2 and glucose based on blue fluorescent carbon dots (CDs) and MnO2 nanosheets with great ability of fluorescence quenching and scattering. Employing CDs@MnO2 nanosheets nanocomposite as the probe, H2O2 is detected by simultaneously collecting first-order scattering (FOS, 353.5 nm), fluorescence (440 nm), and second-order scattering (SOS, 710 nm) under the excitation of 350 nm. H2O2 with strong oxidation property can etch the lamellar structure of MnO2 nanosheets into nano-fragments, which made the fluorescence of CDs in the system recover and the scattering intensity (FOS and SOS) of the system decrease significantly. Therefore, the optical sensor combined FOS and fluorescence signals in ratiometric mode, and SOS signal in turn-off mode to realize sensitive determination of H2O2. The linear ranges of ratiometric mode and turn-off mode for H2O2 detection were 0.2-40 and 0.2-15 µM, respectively. And the limits of detection (LODs) of two modes were 73 and 104 nM, respectively. Furthermore, the sensor was also successfully applied to the detection of glucose which can react to produce H2O2. Satisfactorily, the LODs of this sensor for glucose detection were 95 and 113 nM for ratiometric mode and turn-off mode, respectively. This work not only provides a new method for the accurate detection of H2O2 and glucose, but also extends a new idea for the study of the combination of scattering and fluorescence.

19.
J Hazard Mater ; 416: 126203, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492966

RESUMO

Increasing electrical and electronic waste have raised concerns about the potential toxicity of brominated flame retardants (BFRs) and heavy metals (HMs). However, few studies have focused on the combined effect of BFRs and HMs on microorganisms, especially denitrifying bacteria, which have an essential role in N cycles and N2O emission. Herein, we investigate the combined effect of tetrabromobisphenol A (TBBPA) and Cu on model denitrifying bacteria. A further 24.5% decline in N removal efficiency was observed when 0.05 mg/L Cu were added into a denitrifying system containing 0.75 mg/L TBBPA. Further study demonstrated that Cu heightened the toxicity of TBBPA to denitrification via following aspects: (1) Cu stimulated EPS secretion induced by TBBPA during denitrification, blocked the transmembrane transport of glucose, which caused insufficient carbon substrate for bacteria growth and electron provision; (2) Cu further suppressed key denitrifying enzymes' activity and down-regulated genes involving electron transport induced by TBBPA, led to the decrease of electron transport activity. Finally, the decrease of bacterial growth, insufficient electron donor, and lower electron transport activity caused the synergetic toxic effect of TBBPA and Cu on denitrification. Overall, the present study provides new insights into the combined effect of BFRs and HMs on microorganisms.


Assuntos
Retardadores de Chama , Bifenil Polibromatos , Cobre/toxicidade , Desnitrificação , Transporte de Elétrons , Elétrons , Retardadores de Chama/toxicidade , Bifenil Polibromatos/toxicidade
20.
Nat Metab ; 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545253

RESUMO

Changes in maternal diet and metabolic defects in mothers can profoundly affect health and disease in their progeny. However, the biochemical mechanisms that induce the initial reprogramming events at the cellular level have remained largely unknown owing to limitations in obtaining pure populations of quiescent oocytes. Here, we show that the precocious onset of mitochondrial respiratory quiescence causes a reprogramming of progeny metabolic state. The premature onset of mitochondrial respiratory quiescence drives the lowering of Drosophila oocyte NAD+ levels. NAD+ depletion in the oocyte leads to reduced methionine cycle production of the methyl donor S-adenosylmethionine in embryos and lower levels of histone H3 lysine 27 trimethylation, resulting in enhanced intestinal lipid metabolism in progeny. In addition, we show that triggering cellular quiescence in mammalian cells and chemotherapy-resistant human cancer cell models induces cellular reprogramming events identical to those seen in Drosophila, suggesting a conserved metabolic mechanism in systems reliant on quiescent cells.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...