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1.
Environ Sci Technol ; 57(39): 14648-14660, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37703172

RESUMEN

The frequency of wildfires in the western United States has escalated in recent decades. Here we examine the impacts of wildfires on ground-level ozone (O3) precursors and the O3-NOx-VOC chemistry from the source to downwind urban areas. We use satellite retrievals of nitrogen dioxide (NO2) and formaldehyde (HCHO, an indicator of VOC) from the Tropospheric Monitoring Instrument (TROPOMI) to track the evolution of O3 precursors from wildfires over California from 2018 to 2020. We improved these satellite retrievals by updating the a priori profiles and explicitly accounting for the effects of smoke aerosols. TROPOMI observations reveal that the extensive and intense fire smoke in 2020 led to an overall increase in statewide annual average HCHO and NO2 columns by 16% and 9%. The increase in the level of NO2 offsets the anthropogenic NOx emission reduction from the COVID-19 lockdown. The enhancement of NO2 within fire plumes is concentrated near the regions actively burning, whereas the enhancement of HCHO is far-reaching, extending from the source regions to urban areas downwind due to the secondary production of HCHO from longer-lived VOCs such as ethene. Consequently, a larger increase in NOx occurs in NOx-limited source regions, while a greater increase in HCHO occurs in VOC-limited urban areas, both contributing to more efficient O3 production.


Asunto(s)
Contaminantes Atmosféricos , COVID-19 , Ozono , Compuestos Orgánicos Volátiles , Incendios Forestales , Humanos , Ozono/análisis , Contaminantes Atmosféricos/análisis , Dióxido de Nitrógeno , Control de Enfermedades Transmisibles , Aerosoles y Gotitas Respiratorias , Humo , California , Monitoreo del Ambiente , Compuestos Orgánicos Volátiles/análisis
2.
Molecules ; 28(23)2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38067413

RESUMEN

Cancer is one of the deadliest human diseases, causing high rates of illness and death. Lung cancer has the highest mortality rate among all malignancies worldwide. Effusanin B, a diterpenoid derived from Isodon serra, showed therapeutic potential in treating non-small-cell lung cancer (NSCLC). Further research on the mechanism indicated that effusanin B inhibited the proliferation and migration of A549 cells both in vivo and in vitro. The in vitro activity assay demonstrated that effusanin B exhibited significant anticancer activity. Effusanin B induced apoptosis, promoted cell cycle arrest, increased the production of reactive oxygen species (ROS), and altered the mitochondrial membrane potential (MMP). Based on mechanistic studies, effusanin B was found to inhibit the proliferation and migration of A549 cells by affecting the signal transducer and activator of transcription 3 (STAT3) and focal adhesion kinase (FAK) pathways. Moreover, effusanin B inhibited tumor growth and spread in a zebrafish xenograft model and demonstrated anti-angiogenic effects in a transgenic zebrafish model.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Animales , Humanos , Neoplasias Pulmonares/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Pez Cebra/metabolismo , Transducción de Señal , Angiogénesis , Proliferación Celular , Apoptosis , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Factor de Transcripción STAT3/metabolismo
3.
Environ Sci Technol ; 56(18): 12906-12916, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36083302

RESUMEN

In China, emissions of ozone (O3)-producing pollutants have been targeted for mitigation to reduce O3 pollution. However, the observed O3 decrease is slower than/opposite to expectations affecting the health of millions of people. For a better understanding of this failure and its connection with anthropogenic emissions, we quantify the summer O3 trends that would have occurred had the weather stayed constant by applying a numerical tool that "de-weathers" observations across 31 urban regions (123 cities and 392 sites) over 8 years. O3 trends are significant (p < 0.05) over 234 sites after de-weathering, contrary to the directly observed trends (only 39 significant due to high meteorology-induced variability). The de-weathered data allow categorizing cities in China into four different groups regarding O3 mitigation, with group 1 exhibiting steady O3 reductions, while group 4 showing significant (p < 0.05) O3 increases. Analysis of the relationships between de-weathered odd oxygen and nitrogen oxides illustrates how the changes in NOx, in anthropogenic volatile organic compounds (VOCs), and reductions in fine particulate matter (PM2.5) affect the O3 trends differently in these groups. While this analysis suggests that VOC reductions are the main driver of O3 decreases in group 1, groups 3 and 4 are primarily affected by decreasing PM2.5, which results in enhanced O3 formation. Our analysis demonstrates both the importance of and possibility for isolating emission-driven changes from climate and weather for interpreting short-term air quality observations.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Ozono , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente/métodos , Humanos , Óxidos de Nitrógeno/análisis , Ozono/análisis , Material Particulado/análisis
4.
Environ Sci Technol ; 56(22): 15312-15327, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36219092

RESUMEN

Understanding the local-scale spatial and temporal variability of ozone formation is crucial for effective mitigation. We combine tropospheric vertical column densities (VCDTrop) of formaldehyde (HCHO) and nitrogen dioxide (NO2), referred to as HCHO-VCDTrop and NO2-VCDTrop, retrieved from airborne remote sensing and the TROPOspheric Monitoring Instrument (TROPOMI) with ground-based measurements to investigate changes in ozone precursors and the inferred chemical production regime on high-ozone days in May-August 2018 over two Northeast urban domains. Over New York City (NYC) and Baltimore/Washington D.C. (BAL/DC), HCHO-VCDTrop increases across the domain, but higher NO2-VCDTrop occurs mainly in urban centers on ozone exceedance days (when maximum daily 8 h average (MDA8) ozone exceeds 70 ppb at any monitor in the region). The ratio of HCHO-VCDTrop to NO2-VCDTrop, proposed as an indicator of the sensitivity of local surface ozone production rates to its precursors, generally increases on ozone exceedance days, implying a transition toward a more NOx-sensitive ozone production regime that should lead to higher efficacy of NOx controls on the highest ozone days in NYC and BAL/DC. Warmer temperatures and enhanced influence from emissions in the local boundary layer on the high-ozone days are accompanied by slower wind speeds in BAL/DC but stronger, southwesterly winds in NYC.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Ozono/química , Dióxido de Nitrógeno/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , New England
5.
Geophys Res Lett ; 48(7): e2020GL091520, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-35860786

RESUMEN

Prior work suggests drought exacerbates US air quality by increasing surface ozone concentrations. We analyze 2005-2015 tropospheric column concentrations of two trace gases that serve as proxies for surface ozone precursors retrieved from the OMI/Aura satellite: Nitrogen dioxide (ΩNO2; NOx proxy) and formaldehyde (ΩHCHO; VOC proxy). We find 3.5% and 7.7% summer drought enhancements (classified by SPEI) for ΩNO2 and ΩHCHO, respectively, corroborating signals previously extracted from ground-level observations. When we subset by land cover type, the strongest ΩHCHO drought enhancement (10%) occurs in the woody savannas of the Southeast US. By isolating the influences of precipitation and temperature, we infer that enhanced biogenic VOC emissions in this region increase ΩHCHO independently with both high temperature and low precipitation during drought. The strongest ΩNO2 drought enhancement (6.0%) occurs over Midwest US croplands and grasslands, which we infer to reflect the sensitivity of soil NOx emissions to temperature.

6.
Environ Health ; 20(1): 93, 2021 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-34425829

RESUMEN

BACKGROUND: Air pollution health studies have been increasingly using prediction models for exposure assessment even in areas without monitoring stations. To date, most studies have assumed that a single exposure model is correct, but estimated effects may be sensitive to the choice of exposure model. METHODS: We obtained county-level daily cardiovascular (CVD) admissions from the New York (NY) Statewide Planning and Resources Cooperative System (SPARCS) and four sets of fine particulate matter (PM2.5) spatio-temporal predictions (2002-2012). We employed overdispersed Poisson models to investigate the relationship between daily PM2.5 and CVD, adjusting for potential confounders, separately for each state-wide PM2.5 dataset. RESULTS: For all PM2.5 datasets, we observed positive associations between PM2.5 and CVD. Across the modeled exposure estimates, effect estimates ranged from 0.23% (95%CI: -0.06, 0.53%) to 0.88% (95%CI: 0.68, 1.08%) per 10 µg/m3 increase in daily PM2.5. We observed the highest estimates using monitored concentrations 0.96% (95%CI: 0.62, 1.30%) for the subset of counties where these data were available. CONCLUSIONS: Effect estimates varied by a factor of almost four across methods to model exposures, likely due to varying degrees of exposure measurement error. Nonetheless, we observed a consistently harmful association between PM2.5 and CVD admissions, regardless of model choice.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Enfermedades Cardiovasculares/epidemiología , Exposición a Riesgos Ambientales/efectos adversos , Hospitalización/estadística & datos numéricos , Modelos Teóricos , Material Particulado/efectos adversos , Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales/análisis , Humanos , New York/epidemiología , Material Particulado/análisis
7.
Environ Sci Technol ; 54(11): 6518-6529, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32348127

RESUMEN

Urban ozone (O3) formation can be limited by NOx, VOCs, or both, complicating the design of effective O3 abatement plans. A satellite-retrieved ratio of formaldehyde to NO2 (HCHO/NO2), developed from theory and modeling, has previously been used to indicate O3 formation chemistry. Here, we connect this space-based indicator to spatiotemporal variations in O3 recorded by on-the-ground monitors over major U.S. cities. High-O3 events vary nonlinearly with OMI HCHO and NO2, and the transition from VOC-limited to NOx-limited O3 formation regimes occurs at higher HCHO/NO2 value (3 to 4) than previously determined from models, with slight intercity variations. To extend satellite records back to 1996, we develop an approach to harmonize observations from GOME and SCIAMACHY that accounts for differences in spatial resolution and overpass time. Two-decade (1996-2016) multisatellite HCHO/NO2 captures the timing and location of the transition from VOC-limited to NOx-limited O3 production regimes in major U.S. cities, which aligns with the observed long-term changes in urban-rural gradient of O3 and the reversal of O3 weekend effect. Our findings suggest promise for applying space-based HCHO/NO2 to interpret local O3 chemistry, particularly with the new-generation satellite instruments that offer finer spatial and temporal resolution.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , Ciudades , Monitoreo del Ambiente , Ozono/análisis , Compuestos Orgánicos Volátiles/análisis
8.
J Environ Manage ; 270: 110862, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32721309

RESUMEN

To what extent do the short-term negative externalities of fossil fuel use traverse national borders? Transnational negative externalities are thought to motivate international environmental cooperation, but we often lack detailed data on their occurrence. Using a Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT), we offer global estimates of the extent of transboundary air pollution from coal-fired power generation. In an advance of the existing literature, we attribute the air pollution experienced in different locales to specific coal-fired power plants, allowing us to evaluate the extent to which pollution from the coal industry is experienced across different jurisdictions. Our results indicate that the issue is most severe in South Asia and East Asia. When weighting by the population of "receiving" locations, India is found to be the largest emitter of transboundary air pollution, followed by China. Residents of Bangladesh are found to experience the most transboundary air pollution by a wide margin.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Asia , Bangladesh , China , Carbón Mineral/análisis , India , Centrales Eléctricas
9.
Sensors (Basel) ; 18(5)2018 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-29738512

RESUMEN

Nonrigid multimodal image registration remains a challenging task in medical image processing and analysis. The structural representation (SR)-based registration methods have attracted much attention recently. However, the existing SR methods cannot provide satisfactory registration accuracy due to the utilization of hand-designed features for structural representation. To address this problem, the structural representation method based on the improved version of the simple deep learning network named PCANet is proposed for medical image registration. In the proposed method, PCANet is firstly trained on numerous medical images to learn convolution kernels for this network. Then, a pair of input medical images to be registered is processed by the learned PCANet. The features extracted by various layers in the PCANet are fused to produce multilevel features. The structural representation images are constructed for two input images based on nonlinear transformation of these multilevel features. The Euclidean distance between structural representation images is calculated and used as the similarity metrics. The objective function defined by the similarity metrics is optimized by L-BFGS method to obtain parameters of the free-form deformation (FFD) model. Extensive experiments on simulated and real multimodal image datasets show that compared with the state-of-the-art registration methods, such as modality-independent neighborhood descriptor (MIND), normalized mutual information (NMI), Weber local descriptor (WLD), and the sum of squared differences on entropy images (ESSD), the proposed method provides better registration performance in terms of target registration error (TRE) and subjective human vision.

10.
J Immunother Cancer ; 11(2)2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36725083

RESUMEN

BACKGROUND: To enhance the efficacy of adoptive NK cell therapy against solid tumors, NK cells must be modified to resist exhaustion in the tumor microenvironment (TME). However, the molecular checkpoint underlying NK cell exhaustion in the TME remains elusive. METHODS: We analyzed the correlation between TIPE2 expression and NK cell functional exhaustion in the TME both in humans and mice by single-cell transcriptomic analysis and by using gene reporter mice. We investigated the effects of TIPE2 deletion on adoptively transferred NK cell therapy against cancers by using NK cells from NK-specific Tipe2-deficient mice or peripheral blood-derived or induced pluripotent stem cell (iPSC)-derived human NK cells with TIPE2 deletion by CRISPR/Cas9. We also investigated the potential synergy of double deletion of TIPE2 and another checkpoint molecule, CISH. RESULTS: By single-cell transcriptomic analysis and by using gene reporter mice, we found that TIPE2 expression correlated with NK cell exhaustion in the TME both in humans and mice and that the TIPE2 high NK cell subset correlated with poorer survival of tumor patients. TIPE2 deletion promoted the antitumor activity of adoptively transferred mouse NK cells and adoptively transferred human NK cells, either derived from peripheral blood or differentiated from iPSCs. TIPE2 deletion rendered NK cells with elevated capacities for tumor infiltration and effector functions. TIPE2 deletion also synergized with CISH deletion to further improve antitumor activity in vivo. CONCLUSIONS: This study highlighted TIPE2 targeting as a promising approach for enhancing adoptive NK cell therapy against solid tumors.


Asunto(s)
Inmunoterapia Adoptiva , Péptidos y Proteínas de Señalización Intracelular , Células Asesinas Naturales , Neoplasias , Animales , Humanos , Ratones , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Células Asesinas Naturales/metabolismo , Neoplasias/metabolismo , Microambiente Tumoral
11.
Adv Sci (Weinh) ; 10(12): e2207499, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36807566

RESUMEN

Natural killer (NK) cells not only are innate effector lymphocytes that directly participate in tumor surveillance but are also essential helpers in the antitumor CD8+ T-cell response. However, the molecular mechanisms and potential checkpoints regulating NK cell helper functions remain elusive. Here, it is shown that the T-bet/Eomes-IFN-γ axis in NK cells is essential for CD8+ T cell-dependent tumor control, whereas T-bet-dependent NK cell effector functions are required for an optimal response to anti-PD-L1 immunotherapy. Importantly, NK cell-expressed TIPE2 (tumor necrosis factor-alpha-induced protein-8 like-2) represents a checkpoint molecule for NK cell helper function, since Tipe2 deletion in NK cells not only enhances NK-intrinsic antitumor activity but also indirectly improves the antitumor CD8+ T cell response by promoting T-bet/Eomes-dependent NK cell effector functions. These studies thus reveal TIPE2 as a checkpoint for NK cell helper function, whose targeting might boost the antitumor T cell response in addition to T cell-based immunotherapy.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias , Humanos , Células Asesinas Naturales , Neoplasias/terapia , Neoplasias/patología , Proteínas , Inmunoterapia
12.
Front Cell Infect Microbiol ; 13: 991011, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36779185

RESUMEN

Objective: Urinary tract infection (UTI) is an inflammatory response of the urothelium to bacterial invasion and is a common complication in patients with cutaneous ureterostomy (CU). For such patients, accurate and efficient identification of pathogens remains a challenge. The aim of this study included exploring utility of metagenomic next-generation sequencing (mNGS) in assisting microbiological diagnosis of UTI among patients undergoing CU, identifying promising cytokine or microorganism biomarkers, revealing microbiome diversity change and compare virulence factors (VFs) and antibiotic resistance genes (ARGs) after infection. Methods: We performed a case-control study of 50 consecutive CU patients from December 2020 to January 2021. According to the clinical diagnostic criteria, samples were divided into infected group and uninfected group and difference of urine culture, cytokines, microorganism, ARGs and VFs were compared between the two groups. Results: Inflammatory responses were more serious in infected group, as evidenced by a significant increase in IFN-α (p=0.031), IL-1ß (0.023) and IL-6 (p=0.018). Clinical culture shows that there is higher positive rate in infected group for most clinical pathogens like Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Candida auris etc. and the top three pathogens with positive frequencies were E. coli, K. pneumoniae, and Enterococcus faecalis. Benchmarking clinical culture, the total sensitivity is 91.4% and specificity is 76.3% for mNGS. As for mNGS, there was no significant difference in microbiome α- diversity between infected and uninfected group. Three species biomarkers including Citrobacter freundii, Klebsiella oxytoca, and Enterobacter cloacae are enriched in infected group based on Lefse. E. cloacae were significantly correlated with IL-6 and IL-10. K. oxytoca were significantly correlated with IL-1ß. Besides, the unweighted gene number and weighted gene abundance of VFs or ARGs are significantly higher in infected group. Notablely, ARGs belonging to fluoroquinolones, betalatmas, fosfomycin, phenicol, phenolic compound abundance is significantly higher in infected group which may have bad effect on clinical treatment for patients. Conclusion: mNGS, along with urine culture, will provide comprehensive and efficient reference for the diagnosis of UTI in patients with CU and allow us to monitor microbial changes in urine of these patients. Moreover, cytokines (IL-6, IL-1ß, and IFN-a) or microorganisms like C. freundii, K. oxytoca or E. cloacae are promising biomarkers for building effective UTI diagnostic model of patients with CU and seriously the VFs and ARGs abundance increase in infected group may play bad effect on clinical treatment.


Asunto(s)
Escherichia coli , Infecciones Urinarias , Humanos , Antibacterianos/uso terapéutico , Biomarcadores , Estudios de Casos y Controles , Secuenciación de Nucleótidos de Alto Rendimiento , Interleucina-6 , Klebsiella pneumoniae , Sensibilidad y Especificidad , Ureterostomía , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/microbiología
13.
Oncogene ; 42(35): 2641-2654, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37500797

RESUMEN

Transcription factors (TFs) regulate the expression of genes responsible for cell growth, differentiation, and responses to environmental factors. In this study, we demonstrated that signal-induced proliferation-associated 1 (SIPA1), known as a Rap-GTPase-activating protein, bound DNA and served as a TF. Importin ß1 was found to interact with SIPA1 upon fibronectin treatment. A TGAGTCAB motif was recognized and bound by DNA-binding region (DBR) of SIPA1, which was confirmed by electrophoretic mobility shift assay. SIPA1 regulated the transcription of multiple genes responsible for signal transduction, DNA synthesis, cell adhesion, cell migration, and so on. Transcription of fibronectin 1, which is crucial for cell junction and migration of triple-negative breast cancer (TNBC) cells, was regulated by SIPA1 in a DBR-dependent manner both in vivo and in vitro. Furthermore, single-cell transcriptome sequencing analysis of specimens from a metastatic TNBC patient revealed that SIPA1 was highly expressed in metastatic TNBC. Hence, this study demonstrated that SIPA1 served as a TF, promoting TNBC migration, invasion, and metastasis.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/genética , Fibronectinas/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proliferación Celular/genética , Movimiento Celular/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/metabolismo
14.
Nat Genet ; 55(1): 144-153, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36581701

RESUMEN

Networks are powerful tools to uncover functional roles of genes in phenotypic variation at a system-wide scale. Here, we constructed a maize network map that contains the genomic, transcriptomic, translatomic and proteomic networks across maize development. This map comprises over 2.8 million edges in more than 1,400 functional subnetworks, demonstrating an extensive network divergence of duplicated genes. We applied this map to identify factors regulating flowering time and identified 2,651 genes enriched in eight subnetworks. We validated the functions of 20 genes, including 18 with previously unknown connections to flowering time in maize. Furthermore, we uncovered a flowering pathway involving histone modification. The multi-omics integrative network map illustrates the principles of how molecular networks connect different types of genes and potential pathways to map a genome-wide functional landscape in maize, which should be applicable in a wide range of species.


Asunto(s)
Proteómica , Zea mays , Zea mays/genética , Multiómica , Genómica , Genes de Plantas
15.
Front Immunol ; 13: 1084109, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36591230

RESUMEN

Effective and long-term treatment is required for controlling chronic Hepatitis B Virus (HBV) infection. Natural killer (NK) cells are antiviral innate lymphocytes and represent an essential arm of current immunotherapy. In chronic HBV (CHB), NK cells display altered changes in phenotypes and functions, but preserve antiviral activity, especially for cytolytic activity. On the other hand, NK cells might also cause liver injury in the disease. NK -based immunotherapy, including adoptive NK cell therapy and NK -based checkpoint inhibition, could potentially exploit the antiviral aspect of NK cells for controlling CHB infection while preventing liver tissue damage. Here, we review recent progress in NK cell biology under the context of CHB infection, and discuss potential NK -based immunotherapy strategies for the disease.


Asunto(s)
Hepatitis B Crónica , Humanos , Virus de la Hepatitis B/genética , Antivirales/uso terapéutico , Inmunoterapia
16.
Anal Chim Acta ; 1221: 340026, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35934334

RESUMEN

State-of-the-art Tb-to-Eu energy transfer (TEET) efficiency (>90%) under ultralow Eu3+ proportion (<6%) has been achieved in Eu/Tb bimetallic lanthanide coordination polymers (LnCPs). The yellow-light-emitting sample as sensor exhibits micromolar l-phenylalanine (l-Phe) in water and serum via obvious yellow-to-green luminometric behavior, meanwhile nanomolar-level detection limits are determined in terms of an updated Stern-Volmer equation with high selectivity and competitiveness. Excited-state inter-ligand photon transfer (ESILPT) greatly contributes to superior TEET property and outstanding luminometric behavior. This work opens a window for developing sensitive and stable visualization sensing, being of values on monitoring biochemical markers.


Asunto(s)
Elementos de la Serie de los Lantanoides , Luminiscencia , Colorimetría , Transferencia de Energía , Europio/química , Elementos de la Serie de los Lantanoides/química
17.
ACS Appl Mater Interfaces ; 14(37): 42267-42276, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36075001

RESUMEN

Chemical stability is one of the key concerns in coordination polymers (CPs). However, technologies to protect CPs against acidic or alkaline aqueous environments have yet to be implemented. Herein we demonstrate an approach for improving the pH stability by utilizing the ligand salt as buffering site to modify the unsaturated coordination sites of CPs. For the selective one-dimensional CP Eu-d-DBTA (d-H2DBTA = d-O,O'-dibenzoyltartaric acid) with a pH stability range of 6-8, the introduction of the ligand salt Na-d-DBTA extends the pH stability interval from 3 to 11. Crystallographic structure data reveal the formation of a Eu/Na-d-DBTA dynamic structure with Na-d-DBTA buffer sites on the Eu-O cluster of the Eu-d-DBTA skeleton. Benefiting from the dynamic single-crystal-to-single-crystal transformation, the buffer sites protect the skeleton from the impact of the acidic or alkaline aqueous environment. In addition, Eu/Na-d-DBTA produces stable photoluminescence properties and selective responses toward l-tryptophan (l-Trp) and further toward l-lysine (l-Lys) over the whole buffer capacity range of 3-11. Noticeably, other Ln/Na-d-DBTA CPs and star metal-organic frameworks also exhibit pH stability improvement when the ligand-as-buffer technology is used, which is significant for developing advanced inorganic-organic hybrid materials with superior functionality.

18.
Anal Chim Acta ; 1181: 338905, 2021 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-34556219

RESUMEN

Qualification and quantification of trace organic contaminants necessitates development of highly efficient sensing system, where excited-state inter-ligand proton transfer (ESILPT) provides a feasible pathway to construct efficient chemo-sensors. Herein, a strategically synthesized lanthanide complex, Eu(DBM)3(MeOH)3 (briefly as Eu-DBM-MeOH; DBM = dibenzoylmethane), features two-step ESILPT processes, along with modification on molecular structure and energy band. As a result, Eu-DBM-MeOH exhibits excellent photophysical properties with characteristic luminescence of Eu3+ ion. Benefiting from these merits, the Eu-DBM-MeOH complex acts as ultra-sensitive chemo-sensor toward nanomolar-level nitrofuran antibiotics (nitrofurazone and nitrofurantoin) in water, by disrupting ESILPT processes. Combining the advantages on photophysical property and luminescent sensitivity, ESILPT-active compounds are expected to widen and deepen the research on complex-based luminophores, being potentially useful in trace detection and biological imaging.


Asunto(s)
Elementos de la Serie de los Lantanoides , Nitrofuranos , Ligandos , Protones , Agua
19.
J Cancer ; 12(3): 717-725, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33403029

RESUMEN

Background and Objective: Metastasis is the leading cause of death in patients with advanced non-small cell lung cancer (NSCLC), and epithelial-mesenchymal transition (EMT) is a crucial event in the metastasis of NSCLC. Our previous works demonstrated that NgBR promoted EMT in NSCLC. However, the molecular mechanism was unclear. Methods: TGF-ß1 was used to induce EMT process of NSCLC cells. The biological functions of NgBR in promoting TGF-ß1-induced NSCLC metastasis were studied by gain- and loss-of-function assays both in vitro and in vivo. The underlying mechanisms were studied using molecular biology assays. Results: We found that knockdown of NgBR inhibited TGF-ß1-induced cell migration and invasion in NSCLC cells. In contrast, NgBR overexpression promoted TGF-ß1-induced EMT of A549 cells. Mechanically, we found that knockdown of NgBR facilitated ubiquitination and degradation of TßRI, leading to downregulation of TßRI expression in NSCLC cells. Moreover, we confirmed a positive correlation between NgBR and TßRI in NSCLC tissues. Conclusions: Our findings provide a novel role of NgBR in modulating TGF-ß1-induced EMT and propose NgBR as a new therapeutic target for treating NSCLC patients.

20.
Geohealth ; 4(7): e2020GH000270, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32642628

RESUMEN

The 2018 NASA Health and Air Quality Applied Science Team (HAQAST) "Indicators" Tiger Team collaboration between NASA-supported scientists and civil society stakeholders aimed to develop satellite-derived global air pollution and climate indicators. This Commentary shares our experience and lessons learned. Together, the team developed methods to track wildfires, dust storms, pollen counts, urban green space, nitrogen dioxide concentrations and asthma burdens, tropospheric ozone concentrations, and urban particulate matter mortality. Participatory knowledge production can lead to more actionable information but requires time, flexibility, and continuous engagement. Ground measurements are still needed for ground truthing, and sustained collaboration over time remains a challenge.

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