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2.
Mar Pollut Bull ; 199: 115977, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38194824

RESUMEN

Frame Transplantation System (FTS) is considered an efficient method for seagrass restoration, but the effect of the rusting of iron frame on seagrass restoration remains unclear. We transplanted Zostera marina plants using iron FTS treated with fluorocarbon paint (painted treatment, PT) and traditional unpainted iron FTS (unpainted treatment, UT) under controlled mesocosm conditions for 24 days. Our results showed that the survival rate of Z. marina under the UT was significantly 31.2 % lower than that of the plants under the PT. Soluble sugar content in Z. marina rhizomes under the UT was significantly 2.19 times higher than that of the plants under the PT. Transcriptome analysis revealed differentially expressed genes (DEGs) involved in photosynthesis, metabolism and signal transduction functions. The results provide valuable data that could prove helpful in the development of efficient restoration techniques for Z. marina beds.


Asunto(s)
Zosteraceae , Zosteraceae/metabolismo , Perfilación de la Expresión Génica , Ecología , Plantas , Fotosíntesis
3.
J Comput Assist Tomogr ; 48(2): 334-342, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37757802

RESUMEN

OBJECTIVES: The purpose of this study is to inquire about the potential association between radiomics features and the pathological nature of thyroid nodules (TNs), and to propose an interpretable radiomics-based model for predicting the risk of malignant TN. METHODS: In this retrospective study, computed tomography (CT) imaging and pathological data from 141 patients with TN were collected. The data were randomly stratified into a training group (n = 112) and a validation group (n = 29) at a ratio of 4:1. A total of 1316 radiomics features were extracted by using the pyradiomics tool. The redundant features were removed through correlation testing, and the least absolute shrinkage and selection operator (LASSO) or the minimum redundancy maximum relevance standard was used to select features. Finally, 4 different machine learning models (RF Hybrid Feature, SVM Hybrid Feature, RF, and LASSO) were constructed. The performance of the 4 models was evaluated using the receiver operating characteristic curve. The calibration curve, decision curve analysis, and SHapley Additive exPlanations method were used to evaluate or explain the best radiomics machine learning model. RESULTS: The optimal radiomics model (RF Hybrid Feature model) demonstrated a relatively high degree of discrimination with an area under the receiver operating characteristic curve (AUC) of 0.87 (95% CI, 0.70-0.97; P < 0.001) for the validation cohort. Compared with the commonly used LASSO model (AUC, 0.78; 95% CI, 0.60-0.91; P < 0.01), there is a significant improvement in AUC in the validation set, net reclassification improvement, 0.79 (95% CI, 0.13-1.46; P < 0.05), and integrated discrimination improvement, 0. 20 (95% CI, 0.10-0.30; P < 0.001). CONCLUSION: The interpretable radiomics model based on CT performs well in predicting benign and malignant TNs by using quantitative radiomics features of the unilateral total thyroid. In addition, the data preprocessing method incorporating different layers of features has achieved excellent experimental results. CLINICAL RELEVANCE STATEMENT: As the detection rate of TNs continues to increase, so does the diagnostic burden on radiologists. This study establishes a noninvasive, interpretable and accurate machine learning model to rapidly identify the nature of TN found in CT.


Asunto(s)
Bocio Nodular , Nódulo Tiroideo , Humanos , Radiómica , Estudios Retrospectivos , Nódulo Tiroideo/diagnóstico por imagen
4.
Environ Sci Technol ; 58(4): 1966-1975, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38153028

RESUMEN

Polysaccharides in extracellular polymeric substances (EPS) can form a hybrid matrix network with proteins, impeding waste-activated sludge (WAS) fermentation. Amino sugars, such as N-acetyl-d-glucosamine (GlcNAc) polymers and sialic acid, are the non-negligible components in the EPS of aerobic granules or biofilm. However, the occurrence of amino sugars in WAS and their degradation remains unclear. Thus, amino sugars (∼6.0%) in WAS were revealed, and the genera of Lactococcus and Zoogloea were identified for the first time. Chitin was used as the substrate to enrich a chitin-degrading consortium (CDC). The COD balances for methane production ranged from 83.3 and 95.1%. Chitin was gradually converted to oligosaccharides and GlcNAc after dosing with the extracellular enzyme. After doing enriched CDC in WAS, the final methane production markedly increased to 60.4 ± 0.6 mL, reflecting an increase of ∼62%. Four model substrates of amino sugars (GlcNAc and sialic acid) and polysaccharides (cellulose and dextran) could be used by CDC. Treponema (34.3%) was identified as the core bacterium via excreting chitinases (EC 3.2.1.14) and N-acetyl-glucosaminidases (EC 3.2.1.52), especially the genetic abundance of chitinases in CDC was 2.5 times higher than that of WAS. Thus, this study provides an elegant method for the utilization of amino sugar-enriched organics.


Asunto(s)
Quitinasas , Aguas del Alcantarillado , Amino Azúcares , Fermentación , Ácido N-Acetilneuramínico , Quitina/química , Quitina/metabolismo , Polisacáridos , Quitinasas/química , Quitinasas/metabolismo , Metano
5.
Pancreas ; 52(4): e224-e234, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37747937

RESUMEN

OBJECTIVE: The role E3 ubiquitin ligase membrane-associated RING-CH 8 (MARCH8) has not been studied in pancreatic cancer. METHOD: Pancreatic cancer cell lines and the normal pancreatic cells were tested in vitro studies and male athymic nude mice were tested in vivo studies. Measuring cell viability by Cell Counting Kit-8 assay (CCK8), 5-ethynyl-2'- deoxyuridine (Edu) staining, and colony formation assay. Wound healing assay was implemented for cell migration and Transwell assay was performed for cell invasion to evaluate the histological status by hematoxylin and eosin staining and to detect the protein ubiquitination by ubiquitination assay. The protein expression was determined by immunohistochemistry staining and western blotting, and mRNA expression was measured by quantitative reverse transcription polymerase chain reaction. RESULT: The expression of MARCH8 was increased whereas PTPN4 was decreased in pancreatic cancer cells. Overexpression of MARCH8 promoted the growth, migration, and invasion of cells, and knockdown of PTPN4 had the similar effects both in vitro and in vivo. MARCH8 promoted PTPN4 protein degradation through ubiquitination. Moreover, PTPN4 suppressed the transcription activities of STAT3 by impairing the level of pSTAT3 (705), while inhibition of PTPN4 activated phosphorylation of STAT3. CONCLUSIONS: MARCH8 promoted pancreatic cancer growth and invasion through mediating the degradation of PTPN4 and activated the phosphorylation of STAT3.


Asunto(s)
Neoplasias Pancreáticas , Ubiquitina-Proteína Ligasas , Animales , Masculino , Ratones , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Proteínas de la Membrana/genética , Ratones Desnudos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Humanos , Factor de Transcripción STAT3/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 4/metabolismo
6.
Angew Chem Int Ed Engl ; 62(44): e202309111, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37698233

RESUMEN

Recently, the application of computational tools to the rational design of catalysts has received considerable attention, but progress has been limited by the reliance on databases and because mechanistic data have been almost neglected. Herein, we report a new strategy for catalyst design, designated catalyst-oriented design based on elementary reactions (CODER), which fully utilizes mechanistic data, combines the strengths of computational tools and researcher experience. CODER enabled the development of extremely efficient Pd catalysts for C-N coupling, which markedly improved the efficiency of the synthesis of widely used triarylamine optoelectronic materials by enhancing the turnover numbers (up to 340000) to 1-3 orders of magnitude towards literature values.

7.
Sci Total Environ ; 902: 166152, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37567296

RESUMEN

Marine microplastic (MP) pollution represents a global environmental issue that has ignited considerable apprehension within the international community. Seagrass beds, which serve as nearshore marine ecosystems, have emerged as focal points of plastic and MP contamination due to the pronounced density of anthropogenic activities and the hydrological mitigating effects of submerged vegetation. Nevertheless, our comprehension of MPs within seagrass ecosystems remains constrained. In this study, we employed bibliometric analyses and comprehensive data exploration to summarize the historical progression of the development, pivotal areas of interest, and research deficiencies, followed by proposing future research directions for MP pollution in seagrass beds. The 37 selected papers were sourced from the Web of Science Core Collection scientific database as of December 31st, 2022. Based on the current evaluation, MPs are ubiquitously discovered within seagrass canopies, sediments, and marine organisms, while less than 15 % of seagrass species worldwide have been investigated. Moreover, methodological inconsistencies in sampling, processing and visualization between studies hindered the fusion and comparison of data. MPs in upper sediments and seagrass blades were the most widely investigated, with an average abundance of 263.4 ± 309.2 n/kg and 0.09 ± 0.03 n/blade. In all environmental compartments, the prevalent forms of MPs comprise fibrous and fragmented particles, encompassing the dominant polymers such as polypropylene, polyethylene and polyethylene terephthalate. However, the source of MPs in seagrass beds based on MP characteristics and local hydrodynamics has not been comprehensively analyzed in previous studies. The evidence for MPs acting as pollutants and contaminant carries impacting the growth and decline of seagrass is also weak. Currently, the precise implications of MPs on submerged vegetation, organisms, and the broader seagrass ecosystem remain inconclusive. However, considering the persistent accumulation of MPs, it is imperative to explore the ecological hazards they may pose within the foreseeable future.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Ecosistema , Plásticos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis
8.
Org Lett ; 25(30): 5646-5649, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37487010

RESUMEN

Hydroalumination of olefins generally gives thermodynamically controlled anti-Markovnikov addition selectivity in literatures. In this paper, a highly Markovnikov hydroalumination of aromatic terminal alkenes was realized to prepare various new benzylaluminum complexes by using the well-defined 2,9-diaryl-1,10-phenanthroline modified iron complex as the catalyst and commercially available DIBAL-H as the aluminum hydride reagent. This is the first ironcatalyzed alkene hydroalumination, and the regioselectivity observed in this study is different from the related reactions reported in the literatures.

9.
Front Immunol ; 14: 1172362, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37334386

RESUMEN

Introduction: Multimode thermal therapy (MTT) is an innovative interventional therapy developed for the treatment of liver malignancies. When compared to the conventional radiofrequency ablation (RFA), MTT typically offers improved prognosis for patients. However, the effect of MTT on the peripheral immune environment and the mechanisms underlying the enhanced prognosis have yet to be explored. The aim of this study was to further investigate the mechanisms responsible for the difference in prognosis between the two therapies. Methods: In this study, peripheral blood samples were collected from four patients treated with MTT and two patients treated with RFA for liver malignancies at different time points before and after the treatment. Single cell sequencing was performed on the blood samples to compare and analyze the activation pathways of peripheral immune cells following the MTT and RFA treatment. Results: There was no significant effect of either therapy on the composition of immune cells in peripheral blood. However, the differential gene expression and pathway enrichment analysis demonstrated enhanced activation of T cells in the MTT group compared to the RFA group. In particular, there was a remarkable increase in TNF-α signaling via NF-κB, as well as the expression of IFN-α and IFN-γ in the CD8+ effector T (CD8+ Teff) cells subpopulation, when compared to the RFA group. This may be related to the upregulation of PI3KR1 expression after MTT, which promotes the activation of PI3K-AKT-mTOR pathway. Conclusion: This study confirmed that MTT could more effectively activate peripheral CD8+ Teff cells in patients compared with RFA and promote the effector function, thus resulting in a better prognosis. These results provide a theoretical basis for the clinical application of MTT therapy.


Asunto(s)
Ablación por Catéter , Neoplasias Hepáticas , Ablación por Radiofrecuencia , Humanos , Fosfatidilinositol 3-Quinasas , Transcriptoma , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Ablación por Radiofrecuencia/métodos , Linfocitos T CD8-positivos
10.
J Pineal Res ; 75(1): e12890, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37226314

RESUMEN

Melatonin (MLT) protects cells by reducing reactive oxygen species (ROS) levels, which are key for inducing cellular autophagy. The aim of this study was to investigate the molecular mechanisms underlying MLT regulation of autophagy in granulosa cells (GCs) with BMPR-1B homozygous (FecB BB) and wild type (FecB ++) mutations. GCs collected from small-tailed Han sheep with different FecB genotypes were typed using a TaqMan probe assay, and autophagy levels were found to be significantly higher in GCs with FecB BB than the levels in those with FecB ++. Autophagy-related 2 homolog B (ATG2B) was associated with cell autophagy and was highly expressed in GCs with the FecB BB genotype in small-tailed Han sheep. Overexpression of ATG2B in the GCs of sheep with both FecB genotypes promoted GC autophagy, and the contrary was observed after the inhibition of ATG2B expression. Subsequently, treatment of GCs with different genotypes of FecB and MLT revealed a significant decrease in cellular autophagy and an increase in ATG2B expression. Addition of MLT to GCs with inhibited ATG2B expression revealed that MLT could protect GCs by decreasing ROS levels, especially in GCs with FecB ++ genotype. In conclusion, this study determined that autophagy levels were significantly higher in sheep GCs with FecB BB genotype than the levels in those with FecB ++ genotype, which may have contributed to the difference in lambing numbers between the two FecB genotypes. Autophagy was regulated by ATG2B and was able to protect GCs by reducing the high levels of ROS produced following inhibition of ATG2B through the addition of MLT in vitro.


Asunto(s)
Melatonina , Femenino , Animales , Ovinos , Melatonina/farmacología , Melatonina/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Células de la Granulosa , Genotipo , Autofagia
11.
Water Res ; 235: 119879, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36934541

RESUMEN

Changes in spectral features and molecular weight (MW) of dissolved organic matter (DOM) along the A/A/O processes in eight full-scale wastewater treatment plants (WWTPs) were characterized using size exclusion chromatography with a diode array detector, a fluorescence detector and an organic carbon detector in tandem (SEC-DAD-FLD-OCD) as well as bulk water quality parameters. The parallel factor (PARAFAC) and the nonnegative matrix factorization (NMF) analyses have been effectively applied to the postprocessing of SEC-FLD fingerprints and SEC-OCD chromatograms, respectively. Individual SEC-FLD-PARAFAC or SEC-OCD-NMF components may span a broad range of MW, indicating that these SEC fractions within the same component were cognate and varied coherently across the dataset samples. The SEC-FLD-PARAFAC modeling and SEC-OCD-NMF analysis have clearly and concisely presented that the dramatic decreases of dissolved organic carbon, UV absorbance at 254 nm and protein-like fluorescence at Ex280/Em350 nm in the anaerobic process were primarily associated with the degradation of the large MW proteinaceous and polysaccharide-like biopolymers. It has also revealed that fluorescence of humic acid-like fractions increased significantly during the anaerobic process, but fluorescence of fulvic acid-like and humic substances' building blocks decreased slightly. Laboratory experiments further confirmed the presence of the humification process in anaerobic processes, and the formation of humic acid-like fluorophores may be associated with carbohydrate metabolism. The combination of SEC-FLD-PARAFAC and SEC-OCD-NMF helped to establish the links between changes in bulk water quality parameters and the evolution of SEC MW fractions, which provides a more in-depth insight into wastewater DOM treatability and enables the optimization of wastewater treatment processes.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Materia Orgánica Disuelta , Sustancias Húmicas/análisis , Contaminantes Químicos del Agua/análisis , Proteínas , Cromatografía en Gel , Espectrometría de Fluorescencia/métodos , Análisis Factorial
12.
Water Res ; 232: 119702, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36758356

RESUMEN

Electrochemical oxidation (EO) is an attractive option for treatment of dissolved organic matter (DOM) in landfill leachate but concerns remain over the energy efficiency and formation of oxidation byproducts ClO3- and ClO4-. In this study, EO treatment of landfill leachates was carried out using representative active and nonactive anode materials, cell configurations and current densities. Size exclusion chromatograms coupled with 2D synchronous and asynchronous correlation analysis showed that the sensitivity of DOM fractions to EO degradation was dependent on the anode material. The nonactive boron-doped diamond (BDD) anode demonstrated the best performance for DOM oxidation. The humic acid-like fraction (HA, 2.5-20 kDa) predominated the visible absorbance of landfill leachates at λ ≥400 nm, and it generally had the highest reaction rates except the occurrence of the pH-induced denaturation and precipitation of the proteinaceous biopolymer fraction (BP, >20 kDa). During the EO treatment of landfill leachate with BDD anode, the UV absorbance spectra of landfill leachates at wavelengths <400 nm were affected by the formation of free chlorine. Instead, the decrease of Abs420 was found to be a good indicator of the shift of the oxidation from predominantly HA fraction to the proteinaceous BP fraction. The behavior of the Abs420 parameter was also indicative of the transition from the energy-efficient oxidation of DOM to the dominance of side reactions of chlorine evolution and the subsequent formation of ClO3- and ClO4-. These findings suggest that the EO treatment of landfill leachate can be optimized by adjusting the current density with feedback signals from the online monitoring of Abs420, to achieve a trade-off between degradation of DOM and control of ClO3- and ClO4-.


Asunto(s)
Materia Orgánica Disuelta , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/química , Cloro/análisis , Oxidación-Reducción , Análisis Espectral
13.
Environ Sci Technol ; 57(5): 1894-1906, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-36693029

RESUMEN

Polyurethane (PU) synthetic leathers possess an intricate plastic composition, including polyester (PET) base fabrics and upper PU resin, but the release of fragments from the complexes is unclear. Therefore, we investigated the photodegradation trends of PET base fabrics with PU coating (PET-U) as a representative of composite plastics. Attention was paid to the comparison of the photoaging process of PET-U with that of pure PET base fabric (PET-P). To reveal the potential for chain scission, physical and chemical changes (e.g., surface morphology, molecular weight, and crystallinity) of the two fabrics were explored. The generation of microplastic fibers (MPFs) and microplastic particles (MPPs) was distinguished. Compared with PET-P, PET-U showed a similar but delayed trend in various characteristics and debris release rate as the photoaging time prolonged. Even so, after 360 h of illumination, the generated number of MPs (including MPFs and MPPs) rose considerably to 9.32 × 107 MPs/g, and the amount of released nanoplastics (NPs) increased to 2.70 × 1011 NPs/g from PET-U. The suppression of MP formation from PET-U was potentially directed by the physical shielding of the upper PU layer and the dropped MPs, which resisted the photochemical radical effect. The components of dissolved organic matter derived from plastics (P-DOM) were separated by molecular weight using a size-exclusion chromatography-diode array detector-organic carbon detector/organic nitrogen detector (SEC-DAD-OCD/OND), and the results showed that a larger amount of carbon- and nitrogen-containing chemical substances were generated in PET-U, accompanied by more aromatic and fluorescent compounds. The results provided theoretical bases and insights for future research on the risks of plastic debris from PU synthetic leathers on aquatic organisms and indicated feasible directions for exploring combined pollution studies of plastics.


Asunto(s)
Plásticos , Contaminantes Químicos del Agua , Plásticos/química , Microplásticos , Poliuretanos , Poliésteres , Fotólisis , Contaminantes Químicos del Agua/análisis
14.
J Environ Sci (China) ; 125: 309-318, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36375916

RESUMEN

Accurate quantification of dissolved organic nitrogen (DON) has been a challenge due to the cumulative analytical errors in the conventional method via subtracting dissolved inorganic nitrogen species (DIN) from total dissolved nitrogen (TDN). Size exclusion chromatography coupled with an organic nitrogen detector (SEC-OND) has been developed as a direct method for quantification and characterization of DON. However, the applications of SEC-OND method still subject to poor separations between DON and DIN species and unsatisfied N recoveries of macromolecules. In this study, we packed a series of SEC columns with different lengths and resin materials for separation of different N species and designed an independent vacuum ultraviolet (VUV) oxidation device for complete oxidation converting N species to nitrate. To guarantee sufficient N recoveries, the operation conditions were optimized as oxidation time ≥ 30 min, injection mass (sample concentration × injection volume) < 1000 µL × mg-N/L for macromolecular proteins, and neutral pH mobile eluent. The dissolved O2 concentration in SEC mobile phase determined the upper limit of VUV oxidation at a specific oxidation time. Compared to conventional HW50S column (20 × 250 mm), HW40S column (20 × 350 mm) with mobile phase comprising of 1.5 g/L Na2HPO4·2H2O + 2.5 g/L KH2PO4 (pH = 6.85) could achieve a better separation of DON, nitrite, nitrate, and ammonia. When applied to river water, lake water, wastewater effluent, groundwater, and landfill leachate, the SEC-OND method could quantify DON as well as DIN species accurately and conveniently even the DIN/TDN ratio reached 0.98.


Asunto(s)
Nitratos , Nitrógeno , Nitrógeno/análisis , Nitratos/análisis , Nitritos , Amoníaco/análisis , Materia Orgánica Disuelta , Compuestos Orgánicos/análisis , Cromatografía en Gel , Óxidos de Nitrógeno/análisis , Agua/química
15.
Mar Environ Res ; 182: 105787, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36368210

RESUMEN

Low salinity generally promotes the growth and propagation of temperate seagrasses, but the appropriate range is unclear. We subjected shoots of eelgrass Zostera marina to different salinity levels [10, 15, 20, 25, 30 PSU (control)] for 6 weeks under controlled laboratory conditions. We measured eelgrass responses in terms of survivorship, growth, productivity, leaf pigmentation and carbohydrate concentrations. Survival analysis combined with growth assessment suggested that the optimal salinity range for the propagation of Z. marina shoots was 18-21 PSU. Structural equation model (SEM) analysis indicated that the promotion effect of decreased salinity levels on the survival and growth of Z. marina shoots mainly depended on the increase in chlorophyll content and the accumulation and synthesis of nonstructural carbohydrates. The carotenoid content and soluble sugar content of the aboveground tissues of Z. marina shoots exposed to 20 PSU were 1.1 and 1.6 times higher than those of shoots under the control, respectively. The results will provide valuable data that could prove helpful in the development of efficient artificial propagation technology for Z. marina shoots.


Asunto(s)
Zosteraceae , Salinidad , Clorofila
16.
Mar Pollut Bull ; 184: 114136, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36155412

RESUMEN

We subjected shoots of eelgrass Zostera marina to different combinations of planting density [300 (control), 450, 600, 750, 900 shoots m-2] and sediment fertilization [0 (control), 35, 70, 105, 140 g m-2] for 6 weeks under controlled conditions. We measured eelgrass responses in terms of survivorship, growth, productivity, leaf pigmentation and carbohydrate concentrations. The ramet frequency of Z. marina reached 47.8 % when exposed to the combination of 600 shoots m-2 and 70 g m-2, which was 3.2 times higher than that of shoots under the control. Survival analysis combined with growth assessment suggested that the optimal ranges of planting density and sediment fertilization for the propagation of Z. marina shoots were 501 to 530 shoots m-2 and 51 to 60 g m-2, respectively. The promotion of survival and propagation of Z. marina that stemmed from planting density and sediment fertilization mainly depended on the increase of chlorophyll content and accumulation of non-structural carbohydrate. The total chlorophyll content of Z. marina leaves exposed to the combination of 600 shoots m-2 and 70 g m-2 was 2.1 times higher than that of shoots under the control. The results will provide data that could prove helpful in the development of efficient artificial propagation technology for Z. marina shoots.


Asunto(s)
Zosteraceae , Zosteraceae/fisiología , Plantas , Clorofila , Carbohidratos , Fertilización
17.
Chemosphere ; 308(Pt 3): 136359, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36099987

RESUMEN

The characteristics of dissolved organic matter (DOM) in the influent and secondary effluent from 6 municipal wastewater treatment plants (WWTPs) were investigated with a size exclusion chromatogram (SEC) coupled with multiple detectors to simultaneously detect ultraviolet absorbance, fluorescence, dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) as a function of molecular weight (MW). The SEC chromatograms showed that biopolymers (>6 kDa) and humic substances (0.5-6 kDa) comprised the significant fraction in the influent, while humic substances became the abundant proportion in the secondary effluent. Direct linkages between MW distribution and hydrophobicity of DOM in the secondary effluent were further explored via SEC analysis of XAD resin fractions. DON and DOC with different hydrophobicity exhibited significantly distinct MW distribution, indicating that it was improper to consider DOC as a surrogate for DON. Different from DOC, the order of averaged MW in terms of DON was hydrophobic neutral ≈ transphilic neutral > hydrophobic acid > transphilic acid > hydrophilic fraction. Fluorescence spectral properties exhibited a significant semi-quantitative correlation with MW and hydrophobicity of DOC, with Pearson's coefficients of -0.834 and 0.754 (p < 0.01) for biopolymer and humic substances. Meanwhile, regional fluorescence proportion was demonstrated to indicate the MW and hydrophobicity properties of DON at the semi-quantitative level. The fluorescence excitation-emission matrix (EEM) could be explored to provide a rapid estimation of MW distribution and hydrophobic/hydrophilic proportion of DOC and DON in WWTPs.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Materia Orgánica Disuelta , Sustancias Húmicas/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Peso Molecular , Espectrometría de Fluorescencia , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis
18.
Chemosphere ; 307(Pt 4): 135790, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35940404

RESUMEN

Dissolved organic nitrogen (DON) plays a key role in many biogeochemistry and engineering processes such as forming nitrogenous disinfection byproducts. However, detecting aqueous DON at trace levels is challenging currently because conventional DON conversion methods have very high method detection limits (MDL). In addition, DON is measured indirectly by subtracting dissolved inorganic nitrogen (DIN) from total dissolved nitrogen (TDN), which can propagate analytical errors of each analyte. In order to solve these issues, we isolated DON from DIN with electrodialysis before and herein tested vacuum ultraviolet (VUV) in tandem with several oxidants to convert DON completely into nitrate for subsequent N analysis. Results showed that H2O2 was more suitable than chlorine and persulfate because VUV/chlorine or VUV/persulfate is either inefficient to convert DON or subjected to nonnegligible N loss. To verify the efficiency, we evaluated the effects of typical water and operating variables on the conversions of four model DON compounds and their yields of nitrate. Under optimal conditions (pH 10.3 and 500 mg/L H2O2), the process converted DON completely into nitrate within just 60 min. Compared to conventional TDN analytical methods, the VUV/H2O2 method features not only better analytical precision but also lower MDL because the formed nitrate can be analyzed at very low MDL by ion chromatography (IC). So, this approach moves one step further to achieve a conceptually new DON analytical method by coupling electrodialysis, VUV/H2O2, and IC.


Asunto(s)
Nitratos , Contaminantes Químicos del Agua , Cloro/análisis , Materia Orgánica Disuelta , Agua Dulce , Peróxido de Hidrógeno , Nitratos/análisis , Nitrógeno/análisis , Compuestos Orgánicos/análisis , Oxidantes , Vacio , Agua/química , Contaminantes Químicos del Agua/análisis
19.
Cell Death Dis ; 13(7): 625, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35853854

RESUMEN

Earlier studies have suggested deleted in lymphocytic leukemia 1 (DLEU1), a long non-coding RNA, is a prognostic biomarker for breast cancer. Here we explored the malignant behaviors and underlying mechanisms regulated by DLEU1 in breast cancer. We demonstrated that up-regulation of DLEU1 was detected in breast cancer tissues and cells, particularly in tumors of higher malignancy. DLEU1 knockdown inhibited the growth and the motility of breast cancer cells. Mechanistically, DLEU1 interacted with HIF-1α to collectively activate the transcription of CKAP2. By activating ERK and STAT3 signaling, CKAP2 essentially mediated the pro-tumor activities of DLEU1. In vivo, depletion of DLEU1 inhibited xenograft growth and metastasis of breast cancer cells. Therefore, DLEU1, by acting as a coactivator for HIF-1α, up-regulates CKAP2 expression and promotes malignancy of breast cancer. Targeting DLEU1, HIF-1α, or CKAP2 may thus benefit breast cancer treatment.


Asunto(s)
Neoplasias de la Mama , Proteínas del Citoesqueleto , ARN Largo no Codificante , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Femenino , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Activación Transcripcional , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
20.
Chem Sci ; 13(26): 7873-7879, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35865894

RESUMEN

Although research on iron-catalysed reactions has recently achieved significant progress, the activity and selectivity of iron catalysts are generally inferior to those of noble-metal catalysts. The development of new iron-catalysed reactions, especially those in which iron catalysts exhibit superior activity or selectivity to other catalysts, is the key to promote iron catalysis. Herein, we report the first protocol for iron-catalysed hydroalumination of internal alkynes. Specifically, in the presence of iron catalysts bearing 2,9-diaryl-1,10-phenanthroline ligands, internal alkynes were stereo- and regioselectively hydroaluminated with the commercially available reagent diisobutylaluminum hydride. Compared with other metal-catalysed alkyne hydroalumination reactions reported in the literature, the iron-catalysed protocol has the following advantages: unusual amino-group-directed regioselectivity, a wide substrate scope, good functional group tolerance, high selectivity, and mild reaction conditions. The alkenylaluminum products prepared in this way could undergo a diverse array of transformations, and were used for the synthesis of bioactive compounds. The current study expands the scope of iron catalysis, provides a new efficient access to alkenylaluminum, discloses the origin of the superiority of iron catalysts, and thus may inspire further studies in related fields.

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