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1.
Plant Cell ; 36(7): 2607-2628, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38537937

RESUMEN

Cold injury is a major environmental stress affecting the growth and yield of crops. Brassinosteroids (BRs) and salicylic acid (SA) play important roles in plant cold tolerance. However, whether or how BR signaling interacts with the SA signaling pathway in response to cold stress is still unknown. Here, we identified an SA methyltransferase, TaSAMT1 that converts SA to methyl SA (MeSA) and confers freezing tolerance in wheat (Triticum aestivum). TaSAMT1 overexpression greatly enhanced wheat freezing tolerance, with plants accumulating more MeSA and less SA, whereas Tasamt1 knockout lines were sensitive to freezing stress and accumulated less MeSA and more SA. Spraying plants with MeSA conferred freezing tolerance to Tasamt1 mutants, but SA did not. We revealed that BRASSINAZOLE-RESISTANT 1 (TaBZR1) directly binds to the TaSAMT1 promoter and induces its transcription. Moreover, TaBZR1 interacts with the histone acetyltransferase TaHAG1, which potentiates TaSAMT1 expression via increased histone acetylation and modulates the SA pathway during freezing stress. Additionally, overexpression of TaBZR1 or TaHAG1 altered TaSAMT1 expression and improved freezing tolerance. Our results demonstrate a key regulatory node that connects the BR and SA pathways in the plant cold stress response. The regulatory factors or genes identified could be effective targets for the genetic improvement of freezing tolerance in crops.


Asunto(s)
Brasinoesteroides , Congelación , Regulación de la Expresión Génica de las Plantas , Metiltransferasas , Proteínas de Plantas , Ácido Salicílico , Transducción de Señal , Triticum , Triticum/genética , Triticum/fisiología , Triticum/metabolismo , Brasinoesteroides/metabolismo , Brasinoesteroides/farmacología , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Metiltransferasas/metabolismo , Metiltransferasas/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , Histona Acetiltransferasas/metabolismo , Histona Acetiltransferasas/genética
2.
Nucleic Acids Res ; 52(15): 8702-8716, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39051544

RESUMEN

DNA and RNA nucleobase modifications are biologically relevant and valuable in fundamental biochemical and biophysical investigations of nucleic acids. However, directly introducing site-specific nucleobase modifications into long unprotected oligonucleotides is a substantial challenge. In this study, we used in vitro selection to identify DNAzymes that site-specifically N-alkylate the exocyclic nucleobase amines of particular cytidine, guanosine, and adenosine (C, G and A) nucleotides in DNA substrates, by reductive amination using a 5'-benzaldehyde oligonucleotide as the reaction partner. The new DNAzymes each require one or more of Mg2+, Mn2+, and Zn2+ as metal ion cofactors and have kobs from 0.04 to 0.3 h-1, with rate enhancement as high as ∼104 above the splinted background reaction. Several of the new DNAzymes are catalytically active when an RNA substrate is provided in place of DNA. Similarly, several new DNAzymes function when a small-molecule benzaldehyde compound replaces the 5'-benzaldehyde oligonucleotide. These findings expand the scope of DNAzyme catalysis to include nucleobase N-alkylation by reductive amination. Further development of this new class of DNAzymes is anticipated to facilitate practical covalent modification and labeling of DNA and RNA substrates.


Asunto(s)
Benzaldehídos , ADN Catalítico , Oligonucleótidos , ADN Catalítico/química , ADN Catalítico/metabolismo , Aminación , Alquilación , Oligonucleótidos/química , Oligonucleótidos/metabolismo , Benzaldehídos/química , ADN/química , ADN/metabolismo , Oxidación-Reducción , Catálisis , ARN/química , ARN/metabolismo , Aminas/química
3.
J Sleep Res ; : e14264, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38853286

RESUMEN

Insufficient sleep can significantly affect vigilance and increase slow-wave electroencephalographic power as homeostatic sleep pressure accumulates. Phase-amplitude coupling is involved in regulating the spatiotemporal integration of physiological processes. This study aimed to examine the functional associations of resting-state electroencephalographic power and delta/theta-gamma phase-amplitude coupling from the prefrontal cortex (PFC) to posterior regions with vigilance performance after sleep deprivation. Forty-six healthy adults underwent 24-hr sleep deprivation with resting-state electroencephalographic recordings, and vigilant attention was measured using the Psychomotor Vigilance Task. Power spectral and phase-amplitude coupling analyses were conducted, and correlation analysis was utilized to reveal the relationship between electroencephalographic patterns and changes in vigilance resulting from sleep deprivation. Sleep deprivation significantly declined vigilance performance, accompanied by increased resting-state electroencephalographic power in all bands and delta/theta-gamma phase-amplitude coupling. The increased theta activity in centro-parieto-occipital areas significantly correlated with decreased mean and slowest response speed. Conversely, the increased delta-low gamma and theta-high gamma phase-amplitude couplings negatively correlated with the deceleration of the fastest Psychomotor Vigilance Task reaction times. These findings suggest that sleep deprivation affects vigilance by altering electroencephalographic spectral power and information communication across frequency bands in different brain regions. The distinct effects of increased theta power and delta/theta-gamma phase-amplitude coupling might reflect the impairment and compensation of sleep deprivation on vigilance performance, respectively.

4.
BMC Gastroenterol ; 24(1): 355, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39385074

RESUMEN

BACKGROUND: Gangrene and perforation are severe complications of acute appendicitis, associated with a higher mortality rate compared to uncomplicated appendicitis. Accurate preoperative identification of Gangrenous or perforated appendicitis (GPA) is crucial for timely surgical intervention. METHODS: This retrospective multicenter study includes 796 patients who underwent appendectomy. Univariate and multivariate logistic regression analyses are used to develop a nomogram model for predicting GPA based on laboratory tests and computed tomography (CT) findings. The model is validated using an external dataset. RESULTS: Seven independent predictors were included in the nomogram: white blood cell count, lymphocyte count, D-dimer, serum glucose, albumin, maximum outer diameter of the appendix, and presence of appendiceal fecalith. The nomogram achieved good discrimination and calibration in both the training and testing sets. In the training set, the AUC was 0.806 (95%CI: 0.763-0.849), and the sensitivity and specificity were 82.1% and 66.9%, respectively. The Hosmer-Lemeshow test showed good calibration (P = 0.7378). In the testing set, the AUC was 0.799 (95%CI: 0.741-0.856), and the sensitivity and specificity were 70.5% and 75.3%, respectively. Decision curve analysis (DCA) confirmed the clinical utility of the nomogram. CONCLUSION: The laboratory test-CT nomogram model can effectively identify GPA patients, aiding in surgical decision-making and improving patient outcomes.


Asunto(s)
Apendicectomía , Apendicitis , Gangrena , Nomogramas , Humanos , Apendicitis/cirugía , Apendicitis/sangre , Apendicitis/diagnóstico , Apendicitis/diagnóstico por imagen , Estudios Retrospectivos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Recuento de Leucocitos , Sensibilidad y Especificidad , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Apéndice/patología , Apéndice/diagnóstico por imagen , Recuento de Linfocitos , Modelos Logísticos , Anciano
5.
Environ Sci Technol ; 58(1): 449-458, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38130002

RESUMEN

Nitrogen is an essential nutrient and a major limiting element for the ocean ecosystem. Since the preindustrial era, substantial amounts of nitrogen from terrestrial sources have entered the ocean via rivers, groundwater, and atmospheric deposition. China serves as a key hub in the global nitrogen cycle, but the pathways, sources, and potential mitigation strategies for land-ocean nitrogen transport are unclear. By combining the CHANS, WRF-Chem, and WNF models, we estimated that 8 million tonnes (Tg) of nitrogen was transferred into the ocean in 2017 in China, with atmospheric deposition contributing 1/3. About half variation of the offshore chlorophyll concentration was explained by atmospheric deposition. The Bohai Sea was the hot spot of nitrogen input, estimated at 214 kg N ha-1, while other areas were around 25-51 kg N ha-1. The largest contributors are agricultural systems (4 Tg, 55%), followed by domestic sewage (2 Tg, 21%). Abatement measures could reduce nitrogen export to the ocean by 43%, and mitigating ammonia and nitrogen oxide emissions accounts for 33% of this reduction, highlighting the importance of addressing air pollution in resolving ocean pollution. The cost-benefit analysis suggests the priority of nitrogen reduction in cropland and transport systems for the ocean environment.


Asunto(s)
Contaminación del Aire , Ecosistema , Nitrógeno/análisis , Ambiente , Contaminación Ambiental/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente
6.
Int J Mol Sci ; 25(2)2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38256188

RESUMEN

Nucleotidyl transferases (NTPs) are common transferases in eukaryotes and play a crucial role in nucleotide modifications at the 3' end of RNA. In plants, NTPs can regulate RNA stability by influencing 3' end modifications, which in turn affect plant growth, development, stress responses, and disease resistance. Although the functions of NTP family members have been extensively studied in Arabidopsis, rice, and maize, there is limited knowledge about NTP genes in soybeans. In this study, we identified 16 members of the NTP family in soybeans, including two subfamilies (G1 and G2) with distinct secondary structures, conserved motifs, and domain distributions at the protein level. Evolutionary analysis of genes in the NTP family across multiple species and gene collinearity analysis revealed a relatively conserved evolutionary pattern. Analysis of the tertiary structure of the proteins showed that NTPs have three conserved aspartic acids that bind together to form a possible active site. Tissue-specific expression analysis indicated that some NTP genes exhibit tissue-specific expression, likely due to their specific functions. Stress expression analysis showed significant differences in the expression levels of NTP genes under high salt, drought, and cold stress. Additionally, RNA-seq analysis of soybean plants subjected to salt and drought stress further confirmed the association of soybean NTP genes with abiotic stress responses. Subcellular localization experiments revealed that GmNTP2 and GmNTP14, which likely have similar functions to HESO1 and URT1, are located in the nucleus. These research findings provide a foundation for further investigations into the functions of NTP family genes in soybeans.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Nucleotidiltransferasas , Glycine max/genética , Respuesta al Choque por Frío , Nucleótidos , ARN Nucleotidiltransferasas
7.
Toxicol Appl Pharmacol ; 458: 116328, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36455640

RESUMEN

Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS) that remains incurable. Herein, we demonstrated that ilepcimide (Antiepilepsirine), an antiepileptic drug used for decades, protects mice from experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. Our studies found that ilepcimide treatment effectively ameliorates demyelination, blood-brain barrier leakage and infiltration of CD4+ and CD8+ T cells in EAE mice. On the one hand, ilepcimide can inhibit dihydroorotate dehydrogenase (DHODH), an important therapeutic target for MS. Computer molecular docking, thermal shift and fluorescence quenching assay demonstrated the directly interaction between ilepcimide and DHODH. Accordingly, ilepcimide observably repressed T cell proliferation in mixed lymphocyte reaction (MLR) assay and concanavalin A (Con-A) model in a DHODH-dependent manner. On the other hand, ilepcimide exhibited neuroprotective effect possibly through activating NRF2 antioxidant pathway in mouse neural crest-derived Neuro2a cells. Collectively, our findings have revealed the therapeutic potential of ilepcimide in EAE mouse model via restricting inflammatory response and oxidative stress, offering a potential opportunity for repurposing existing drug ilepcimide for MS therapy.


Asunto(s)
Reposicionamiento de Medicamentos , Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Animales , Ratones , Linfocitos T CD8-positivos , Dihidroorotato Deshidrogenasa , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Ratones Endogámicos C57BL , Simulación del Acoplamiento Molecular , Esclerosis Múltiple/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Inflamación/tratamiento farmacológico
8.
Environ Sci Technol ; 57(35): 13124-13135, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37616592

RESUMEN

Ammonia (NH3) is critical to the nitrogen cycle and PM2.5 formation, yet a great deal of uncertainty exists in its urban emission quantifications. Model-underestimated NH3 concentrations have been reported for cities, yet few studies have provided an explanation. Here, we explore reasons for severe WRF-Chem model underestimations of NH3 concentrations in Beijing in August 2018, including simulated gas-particle partitioning, meteorology, regional transport, and emissions, using spatially refined (3 km resolution) NH3 emission estimates in the agricultural sector for Beijing-Tianjin-Hebei and in the traffic sector for Beijing. We find that simulated NH3 concentrations are significantly lower than ground-based and satellite observations during August in Beijing, while wintertime underestimations are much more moderate. Further analyses and sensitivity experiments show that such discrepancies cannot be attributed to factors other than biases in NH3 emissions. Using site measurements as constraints, we estimate that both agricultural and non-agricultural NH3 emission totals in Beijing shall increase by ∼5 times to match the observations. Future research should be performed to allocate underestimations to urban fertilizer, power, traffic, or residential sources. Dense and regular urban NH3 observations are necessary to constrain and validate bottom-up inventories and NHx simulation.


Asunto(s)
Agricultura , Amoníaco , Beijing , China , Ciudades
9.
J Virol ; 95(22): e0111921, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34468170

RESUMEN

Monocyte chemotactic protein-induced protein 1 (MCPIP1) is an inflammatory regulator in immune response and has broad antiviral effects by targeting viral RNA. Porcine reproductive and respiratory syndrome virus (PRRSV), a major viral pathogen in pigs, causes immune suppression leading to coinfection of swine pathogens, but the mechanisms are not fully clarified. In this study, MCPIP1 expression was found to be significantly upregulated in lungs of PRRSV-infected piglets, as well as in Marc-145 and porcine pulmonary alveolar macrophage (PAM) cells upon PRRSV stimulation. MCPIP1 overexpression significantly inhibited PRRSV replication, while MCPIP1 knockdown increased the virus titer. Various mutations in RNase functional domains of MCPIP1 impaired the inhibitory activity against PRRSV, while those in deubiquitinase domains failed to do so. MCPIP1 expression started to decrease from 60 h after PRRSV infection in PAMs. Meanwhile, infection with higher dose of PRRSV further downregulated MCPIP1, indicating the antagonizing effects from PRRSV against MCPIP1. Moreover, it was confirmed that MCPIP1 expression was downregulated in 3D4 cells with either interleukin-17 (IL-17) or nsp11 overexpression, while IL-17 inhibitor abolished the decrease of MCPIP1 caused by nsp11, indicating nsp11 employs IL-17 induction to inhibit MCPIP1. Furthermore, the PRRSV nsp11 mutant with a deficiency in IL-17 induction showed the recovered expression of MCPIP1 in infected cells, inspiring a strategy for virus attenuation. This is the first report about the role of MCPIP1 against PRRSV and the function of PRRSV nsp11 against innate immunity to facilitate virus replication via IL-17. The study not only illuminates PRRSV infection machinery but also enlightens alternative antiviral strategies, such as vaccine candidates. IMPORTANCE Porcine reproductive and respiratory syndrome virus (PRRSV) suppresses the innate immunity and leads to coinfection of swine pathogens. Monocyte chemotactic protein-induced protein 1 (MCPIP1) is a broad-spectrum host antiviral protein. Therefore, to further clarify the mechanism of PRRSV against innate immunity, we explored the relationship between MCPIP1 and PRRSV infection. The results showed that MCPIP1 inhibited PRRSV infection in the early stage of virus infection. Importantly, PRRSV nsp11 subsequently employed IL-17 induction to suppress MCPIP1 expression and antagonized anti-PRRSV effects. Furthermore, PRRSV with mutation of nsp11 S74A failed to induce MCPIP1 reduction. These findings confirmed the function of MCPIP1 against PRRSV and revealed that PRRSV nsp11 plays an important role in virus against innate immunity. This study enlightens a new strategy to develop safer attenuated vaccines against PRRSV by nsp11 mutation.


Asunto(s)
Factores de Restricción Antivirales/inmunología , Quimiocina CCL2/inmunología , Interleucina-17/inmunología , Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino/inmunología , Replicación Viral/inmunología , Animales , Línea Celular , Haplorrinos , Humanos , Inmunidad Innata , Macrófagos Alveolares , Síndrome Respiratorio y de la Reproducción Porcina/inmunología , Síndrome Respiratorio y de la Reproducción Porcina/virología , Porcinos
10.
New Phytol ; 236(2): 590-607, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35832009

RESUMEN

Plants have evolved a two-branched innate immune system to detect and cope with pathogen attack, which are initiated by cell-surface and intracellular immune receptors leading to pattern-triggered immunity (PTI) and effector-triggered immunity (ETI), respectively. A core transducer including PAD4-EDS1 node is proposed as the convergence point for a two-tiered immune system in conferring pathogen immunity. However, the transcriptional regulatory mechanisms controlling expression of these key transducers remain largely unknown. Here, we identified histone acetyltransferase TaHAG1 as a positive regulator of powdery mildew resistance in wheat. TaHAG1 regulates expression of key transducer gene TaPAD4 and promotes SA and reactive oxygen species accumulation to accomplish resistance to Bgt infection. Moreover, overexpression and CRISPR-mediated knockout of TaPAD4 validate its role in wheat powdery mildew resistance. Furthermore, TaHAG1 physically interacts with TaPLATZ5, a plant-specific zinc-binding protein. TaPLATZ5 directly binds to promoter of TaPAD4 and together with TaHAG1 to potentiate the expression of TaPAD4 by increasing the levels of H3 acetylation. Our study revealed a key transcription regulatory node in which TaHAG1 acts as an epigenetic modulator and interacts with TaPLATZ5 that confers powdery mildew resistance in wheat through activating a convergence point gene between PTI and ETI, which could be effective for genetic improvement of disease resistance in wheat and other crops.


Asunto(s)
Ascomicetos , Triticum , Ascomicetos/fisiología , Resistencia a la Enfermedad/genética , Histona Acetiltransferasas/metabolismo , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Triticum/metabolismo
11.
Environ Sci Technol ; 56(11): 7131-7142, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35302752

RESUMEN

High-resolution (e.g., 5 km) emission data of nitrogen oxides (NOx = NO + NO2) provide localized knowledge of pollution sources for targeted regulations, yet such data are lacking or inaccurate over most regions at present. Here we improve our PHLET-based inversion method to derive NOx emissions in China at a 5-km resolution in summer 2019, based on the TROPOMI-POMINO satellite product of nitrogen dioxide (NO2) columns. With low computational costs, our inversion explicitly accounts for the effects of horizontal transport and nonlinear chemistry. We find numerous small-to-medium sources related to minor roads and small human settlements at relatively low affluence levels, in addition to clear emission signals along major transportation lines, consistent with road line density and Tencent location data. Many small-to-medium sources and transportation emissions are unclear or missing in the spatial distributions of four widely used emission inventories. Our emissions offer a unique reference for targeted emission control.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente , Humanos , Dióxido de Nitrógeno/análisis , Óxidos de Nitrógeno/análisis , Emisiones de Vehículos/análisis
12.
J Nanobiotechnology ; 20(1): 493, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36424615

RESUMEN

BACKGROUND: Virus-like particles (VLPs) are supramolecular structures composed of multiple protein subunits and resemble natural virus particles in structure and size, making them highly immunogenic materials for the development of next-generation subunit vaccines. The orderly and repetitive display of antigenic epitopes on particle surface allows efficient recognition and cross-link by B cell receptors (BCRs), thereby inducing higher levels of neutralizing antibodies and cellular immune responses than regular subunit vaccines. Here, we present a novel multiple antigen delivery system using SpyCatcher/Spytag strategy and self-assembled VLPs formed by porcine circovirus type 2 (PCV2) Cap, a widely used swine vaccine in solo. RESULTS: Cap-SC, recombinant Cap with a truncated SpyCatcher polypeptide at its C-terminal, self-assembled into 26-nm VLPs. Based on isopeptide bonds formed between SpyCatcher and SpyTag, classical swine fever virus (CSFV) E2, the antigen of interest, was linked to SpyTag and readily surface-displayed on SpyCatcher decorated Cap-SC via in vitro covalent conjugation. E2-conjugated Cap VLPs (Cap-E2 NPs) could be preferentially captured by antigen presenting cells (APCs) and effectively stimulate APC maturation and cytokine production. In vivo studies confirmed that Cap-E2 NPs elicited an enhanced E2 specific IgG response, which was significantly higher than soluble E2, or the admixture of Cap VLPs and E2. Moreover, E2 displayed on the surface did not mask the immunodominant epitopes of Cap-SC VLPs, and Cap-E2 NPs induced Cap-specific antibody levels and neutralizing antibody levels comparable to native Cap VLPs. CONCLUSION: These results demonstrate that this modularly assembled Cap-E2 NPs retains the immune potential of Cap VLP backbone, while the surface-displayed antigen significantly elevated E2-induced immune potency. This immune strategy provides distinctly improved efficacy than conventional vaccine combination. It can be further applied to the development of dual or multiple nanoparticle vaccines to prevent co-infection of PCV2 and other swine pathogens.


Asunto(s)
Circovirus , Nanopartículas , Porcinos , Animales , Vacunas Combinadas , Anticuerpos Neutralizantes , Vacunas de Subunidad
13.
Ecotoxicol Environ Saf ; 248: 114324, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36434998

RESUMEN

Decabromodiphenyl ether (BDE-209), the primary constituent of a widely used flame retardant formulation, is often present in high levels in avian derived products and could be transferred to humans through consumption. The purpose of this study was to investigate the toxicokinetics and bioaccumulation patterns of BDE-209 in different tissues of broilers, which would benefit the evaluation of chicken product safety. Male broilers received a single oral administration of BDE-209 at 25 mg/kg.BW and then BDE-209 concentrations in the plasma, liver, leg muscle, breast muscle, and other tissues were measured using gas chromatography-electron capture detection (GC-ECD). The changes of BDE-209 concentrations in the plasma were fitted to a non-compartmental model for kinetic analysis. Peak values were observed at 24 h (t1/2 =168.28 h), and trace levels remained for four weeks. Additionally, Cmax in the liver was much higher than that in leg and breast muscles, and Tmax from the liver and muscle were 12 and 24 h, respectively. Residual BDE-209 was detected in all broiler tissues after 2 weeks, and concentrations were ranked as follows: fat > liver > thymus gland > heart > testis > thigh muscle > skin > lung > kidney > breast muscles > spleen (wet weight (ww)). Our results suggested that BDE-209 was widely distributed in different tissues after intestinal absorption, and preferentially accumulated in adipose and liver tissues. Observations of bioaccumulation and slow elimination in the liver and muscles provide critical insight into the toxicity of BDE-209 and risk assessment of edible tissues from broilers.


Asunto(s)
Pollos , Éteres Difenilos Halogenados , Animales , Humanos , Masculino , Toxicocinética , Bioacumulación , Cinética , Éteres Difenilos Halogenados/toxicidad , Músculos Pectorales
14.
Ecotoxicol Environ Saf ; 219: 112305, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34029840

RESUMEN

The wide usage of decabromodiphenyl ether (BDE-209) results in its increasing occurrence in the environment and increasing attention in regard to human and animal health. BDE-209 is an endocrine disruptor for hypothyroidism, but the toxicity mechanism is unclear. Here, the histopathology and transcriptome sequencing of thyroid tissue from broiler chicks were investigated by supplemental feeding with different concentrations of BDE-209 for 42 days (0-4 g/kg in basal diet), followed by determining the levels of thyroid hormones in serum. The results showed ruptured and even hyperplastic follicular epithelial cells in the thyroid, and a total of 501 differentially expressed genes were screened out: 222 upregulated and 279 downregulated. Based on the Kyoto Encyclopedia of Genes and Genomes database, neuroactive ligand-receptor interaction pathway was significantly enriched, and α1D-adrenergic receptor, follicle-stimulating hormone receptor, thyroid stimulating hormone receptor, and somatostatin receptor type 2 were shown to be candidate biomarkers. Thyroxine was a possible biomarker due to clear reduction in serum and significant correlation with exposure concentrations. These results suggested that oral intake of BDE-209 can cause structural injuries and even hyperplasia, and affect gene transcription involved in the neuroactive ligand-receptor interaction pathway of thyroid, as well as thyroid hormones in serum.


Asunto(s)
Retardadores de Llama/toxicidad , Éteres Difenilos Halogenados/toxicidad , Animales , Pollos/metabolismo , Disruptores Endocrinos/toxicidad , Perfilación de la Expresión Génica , Humanos , Glándula Tiroides/efectos de los fármacos , Hormonas Tiroideas/metabolismo , Tiroxina/metabolismo , Transcriptoma
15.
Ecotoxicol Environ Saf ; 213: 112022, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33609999

RESUMEN

A reliable and simple modified QuEChERS method with UPLC-MS/MS was developed for the simultaneous determination of six pesticides (dimethomorph, imidaclothiz, lufenuron, methoxyfenozide, pyridaben, spinetoram) and their metabolites in pak choi. Method validation indicated good linearity (R2 ≥ 0.99), accuracy (recoveries of 75%-112%), sensitivity (limits of quantification, 0.002-0.01 mg kg-1), and precision (relative standard deviations ≤ 21%), and matrix effects were -36-28%. The half-lives of the six pesticides in pak choi were 2.2-12 d under open field and greenhouse conditions. Considering the short growth cycle of pak choi, the terminal residue levels (0.046-7.8 mg kg-1) and the relevant maximum residue limits (MRLs) of some countries, 5 d was recommended as the pre-harvest interval for the six pesticides on pak choi. Dietary risk assessment revealed that the risk quotients were 3.1%-58% for different gender and age groups in China, indicating none unacceptable public health risk for general population. The results showed that all the six pesticides degraded faster and the terminal residues were much lower under open field conditions than those under greenhouse conditions, which was mainly due to the influence of rainfall, sunlight and other environmental factors. This work was thus significant in assessing the dissipation fate and food safety risks of the six pesticides on pak choi and facilitated the establishment of maximum residue limits.


Asunto(s)
Brassica/química , Exposición Dietética/estadística & datos numéricos , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , China , Cromatografía Líquida de Alta Presión , Cromatografía Liquida/métodos , Inocuidad de los Alimentos , Hidrazinas , Hormonas Juveniles , Macrólidos , Plaguicidas/toxicidad , Medición de Riesgo , Espectrometría de Masas en Tándem/métodos
16.
Water Sci Technol ; 84(9): 2278-2287, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34810311

RESUMEN

Ti-based electrode coated with MnOx catalytic layer has presented superior electrochemical activity for degradation of organic pollution in wastewater, however, the industrial application of Ti-based MnOx electrode is limited by the poor stability of the electrode. In this study, the novel Ti-based MnOx electrodes co-incorporated with rare earth (Ce) and conductive carbon black (C) were prepared by spraying-calcination method. The Ti/Ce:MnOx-C electrode, with uniform and integrated surface and enhanced Mn(IV) content by C and Ce co-incorporation, could completely remove ammonia nitrogen (NH4+-N) with N2 as the main product. The cell potential and energy consumption of Ti/Ce:MnOx-C electrode during the electrochemical process was significantly reduced compared with Ti/MnOx electrode, which mainly originated from the enhanced electrochemical activity and reduced charge transfer resistance by Ce and C co-incorporation. The accelerated lifetime tests in sulfuric acid showed that the actual service lifetime of Ti/Ce:MnOx-C was ca. 25 times that of Ti/MnOx, which demonstrated the significantly promoted stability of MnOx-based electrode by Ce and C co-incorporation.


Asunto(s)
Amoníaco , Titanio , Electrodos , Nitrógeno , Oxidación-Reducción , Hollín
17.
Entropy (Basel) ; 23(7)2021 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-34356454

RESUMEN

The development of oil and gas resources is gradually transferring to the deep sea, and the hydrate plugging of submarine pipelines at high pressures and low temperatures is becoming an important problem to ensure the safety of pipeline operations. The swirl flow is a new method to expand the boundary of hydrate safe flow. Numerical simulation of the hydrate slurry flow characteristics in a horizontal pipeline by twisted band has been carried out, and the flow of CO2 hydrate slurry in low concentration has been simulated by the RSM and DPM models. The results show that the heat transfer efficiency is also related to Re and particle concentration. The velocity distribution has the form of symmetrical double peaks, and the peaks finally merge at the center of the pipeline. Vortexes firstly appear on both sides of the edge of the twisted band, and then move to the middle part of the twisted band. Finally, the vortex center almost coincides with the velocity center. The rotation direction of hydrate particles is the same as the twisted direction of the twisted band, twist rate (Y) is smaller, Re is larger, and the symmetric vortex lines merge farther away. The initial swirl number is mainly related to Y, but not Re. The swirl flow attenuates exponentially, and its attenuation rate is mainly related to Re, but not Y. Compared with ordinary pipelines, the swirl flow can obviously improve the transportation distance of hydrate slurry.

18.
J Vasc Interv Radiol ; 31(1): 42-48, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31831324

RESUMEN

PURPOSE: The association between occupational radiation exposure and endothelium-dependent vasodilation (EDV) remains unclear. This study evaluated the association between radiation exposure and EDV among fluoroscopy-guided interventional procedure specialists and explored the possible mechanisms. MATERIALS AND METHODS: Brachial flow-mediated dilation was compared in 21 interventional cardiologists (the radiation group) and 15 noninterventional cardiologists (the nonradiation group). Animal radiation experiments were also performed to observe the impact of radiation on EDV. RESULTS: Flow-mediated dilation in both the left (radiation group, 3.63% vs. nonradiation group, 6.77%; P < .001) and right brachial arteries (5.36% vs. 7.33%, respectively; P = .04) and serum nitric oxide (NO) level (343.69 vs. 427.09 µmol/L, respectively; P = .02) were significantly reduced in the radiation group compared to those in the nonradiation group. EDV was significantly impaired in acetylcholine concentrations of 3 × 10-6 mol/L and 10-5 mol/L (60.09% vs.74.79%, respectively; P = .03; and 62.73% vs. 80.56%, respectively; P = .002), and reactive oxygen species levels in the aorta intima and media layers were significantly increased in mice after a single x-ray exposure, which could be partly rescued by pretreatment with folic acid (P < .05). CONCLUSIONS: Radiation exposure can lead to impairment of flow-mediated vasodilation in human or EDV in mice. In mice acutely exposed to radiation, folic acid alleviated radiation-induced EDV impairment by possible reduction of reactive oxidative species.


Asunto(s)
Aorta/efectos de la radiación , Arteria Braquial/efectos de la radiación , Exposición Profesional/efectos adversos , Salud Laboral , Dosis de Radiación , Exposición a la Radiación/efectos adversos , Radiografía Intervencional/efectos adversos , Radiólogos , Vasodilatación/efectos de la radiación , Adulto , Animales , Antioxidantes/farmacología , Aorta/efectos de los fármacos , Aorta/metabolismo , Aorta/fisiopatología , Arteria Braquial/metabolismo , Arteria Braquial/fisiopatología , Estudios de Casos y Controles , Femenino , Ácido Fólico/farmacología , Humanos , Masculino , Ratones , Persona de Mediana Edad , Óxido Nítrico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
19.
Ecotoxicol Environ Saf ; 170: 306-313, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30530183

RESUMEN

Novel brominated flame retardants (NBFRs), which are lipophilic compounds that have been widely applied after the phasing-out of legacy BFRs, can bioaccumulate through the food chain. However, information on NBFRs in animal feeds, the beginning of farm-to-fork pathway, is very limited. Fishmeal is one of the most widely applied feedstuff worldwide. The present study identified eleven NBFRs from ninety-two globally collected fishmeal samples with levels in the range of 0.13-822 (mean: 15.1 ±â€¯85.5) ng/g lipid weight (lw). Hexabromobenzene (HBB) and pentabromotoluene (PBT) were the most prevalent contributors (detection frequencies: 95.7% and 73.9%, respectively), and decabromodiphenylethane (DBDPE) was the weightiest contributor (accounted for 67.1% of the ΣNBFRs, mean: 12.1 ±â€¯84.8 ng/g lw). From a geographical view, the highest NBFR level was found in Chinese fishmeal. The NBFRs fell within an order of magnitude in South America, Southeast Asia, Europe and United States. DBDPE was predominant in the fishmeal collected from China, South America and United States, but it was not detected in European fishmeal. The NBFR levels are significantly lower compared to the polybrominated diphenyl ethers (PBDEs) (p < 0.01), indicating that the distribution of NBFRs was not as wide as PBDEs in fishmeal. DBDPE was significantly correlated with BDE209 (r = 0.557, p < 0.01), which implies that the two chemicals might have similar sources. Quantitative structure-activity relationship (QSAR)results imply that the NBFRs might have similar persistence and biomagnification potential as legacy lipophilic POPs.


Asunto(s)
Alimentación Animal/análisis , Bromobencenos/análisis , Monitoreo del Ambiente/métodos , Retardadores de Llama/análisis , Contaminación de Alimentos/análisis , Tolueno/análogos & derivados , Animales , China , Europa (Continente) , Cadena Alimentaria , Relación Estructura-Actividad Cuantitativa , América del Sur , Tolueno/análisis
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