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1.
Plant Physiol ; 194(2): 1181-1203, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37930306

RESUMEN

Drought stress is a key environmental factor limiting the productivity, quality, and geographic distribution of crops worldwide. Abscisic acid (ABA) plays an important role in plant drought stress responses, but the molecular mechanisms remain unclear. Here, we report an ABA-responsive bHLH transcription factor, MdbHLH160, which promotes drought tolerance in Arabidopsis (Arabidopsis thaliana) and apple (Malus domestica). Under drought conditions, MdbHLH160 is directly bound to the MdSOD1 (superoxide dismutase 1) promoter and activated its transcription, thereby triggering reactive oxygen species (ROS) scavenging and enhancing apple drought tolerance. MdbHLH160 also promoted MdSOD1 enzyme activity and accumulation in the nucleus through direct protein interactions, thus inhibiting excessive nuclear ROS levels. Moreover, MdbHLH160 directly upregulated the expression of MdDREB2A-like, a DREB (dehydration-responsive element binding factor) family gene that promotes apple drought tolerance. Protein degradation and ubiquitination assays showed that drought and ABA treatment stabilized MdbHLH160. The BTB protein MdBT2 was identified as an MdbHLH160-interacting protein that promoted MdbHLH160 ubiquitination and degradation, and ABA treatment substantially inhibited this process. Overall, our findings provide insights into the molecular mechanisms of ABA-modulated drought tolerance at both the transcriptional and post-translational levels via the ABA-MdBT2-MdbHLH160-MdSOD1/MdDREB2A-like cascade.


Asunto(s)
Arabidopsis , Malus , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resistencia a la Sequía , Especies Reactivas de Oxígeno/metabolismo , Arabidopsis/metabolismo , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/metabolismo , Estrés Fisiológico/genética
2.
Plant J ; 116(3): 669-689, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37471682

RESUMEN

Salt stress adversely affects the yield and quality of crops and limits their geographical distribution. Studying the functions and regulatory mechanisms of key genes in the salt stress response is important for breeding crops with enhanced stress resistance. Autophagy plays an important role in modulating the tolerance of plants to various types of abiotic stressors. However, the mechanisms underlying salt-induced autophagy are largely unknown. Cation/Ca2+ exchanger proteins enhance apple salt tolerance by inhibiting Na+ accumulation but the mechanism underlying the response to salt stress remains unclear. Here, we show that the autophagy-related gene MdATG18a modulated apple salt tolerance. Under salt stress, the autophagic activity, proline content, and antioxidant enzyme activities were higher and Na+ accumulation was lower in MdATG18a-overexpressing transgenic plants than in control plants. The use of an autophagy inhibitor during the salt treatment demonstrated that the regulatory function of MdATG18a depended on autophagy. The yeast-one-hybrid assay revealed that the homeodomain-leucine zipper (HD-Zip) transcription factor MdHB7-like directly bound to the MdATG18a promoter. Transcriptional regulation and genetic analyses showed that MdHB7-like enhanced salt-induced autophagic activity by promoting MdATG18a expression. The analysis of Na+ efflux rate in transgenic yeast indicated that MdCCX1 expression significantly promoted Na+ efflux. Promoter binding, transcriptional regulation, and genetic analyses showed that MdHB7-like promoted Na+ efflux and apple salt tolerance by directly promoting MdCCX1 expression, which was independent of the autophagy pathway. Overall, our findings provide insight into the mechanism underlying MdHB7-like-mediated salt tolerance in apple through the MdHB7-like-MdATG18a and MdHB7-like-MdCCX1 modules. These results will aid future studies on the mechanisms underlying stress-induced autophagy and the regulation of stress tolerance in plants.


Asunto(s)
Malus , Malus/metabolismo , Tolerancia a la Sal/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/genética , Fitomejoramiento , Plantas Modificadas Genéticamente/genética , Autofagia/genética , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico/genética
3.
Plant Physiol ; 191(1): 789-806, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36331333

RESUMEN

Low temperature affects the yield and quality of crops. Inducer of CBF expression 1 (ICE1) plays a positive role in plant cold tolerance by promoting the expression of CRT binding factor (CBF) and cold-responsive (COR) genes. Several ICE1-interacting transcription factors (TFs) that regulate plant cold tolerance have been identified. However, how these TFs affect the function of ICE1 and CBF expression under cold conditions remains unclear. Here, we identified the MYC-type TF MdbHLH4, a negative regulator of cold tolerance in Arabidopsis (Arabidopsis thaliana) and apple (Malus domestica) plants. Under cold conditions, MdbHLH4 inhibits the expression of MdCBF1 and MdCBF3 by directly binding to their promoters. It also interacts with MdICE1L, a homolog of AtICE1 in apple, and inhibits the binding of MdICE1L to the promoters of MdCBF1/3 and thus their expression. We showed that MdCAX3L-2, a Ca2+/H+ exchanger (CAX) family gene that negatively regulates plant cold tolerance, is also a direct target of MdbHLH4. MdbHLH4 reduced apple cold tolerance by promoting MdCAX3L-2 expression. Moreover, overexpression of either MdCAX3L-2 or MdbHLH4 promoted the cold-induced ubiquitination and degradation of MdICE1L. Overall, our results reveal that MdbHLH4 negatively regulates plant cold tolerance by inhibiting MdCBF1/3 expression and MdICE1L promoter-binding activity, as well as by promoting MdCAX3L-2 expression and cold-induced MdICE1L degradation. These findings provide insights into the mechanisms by which ICE1-interacting TFs regulate CBF expression and ICE1 function and thus plant cold tolerance.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Malus , Malus/metabolismo , Frío , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
4.
Environ Res ; 252(Pt 2): 118842, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38583656

RESUMEN

This study investigates the distribution of rare earth elements (REEs) within the Beijing water system, specifically examining the Yongding, Chaobai, Beiyun, Jiyun, and Daqing rivers. Results indicate that the Beiyun River exhibits the highest REE concentrations, ranging from 35.95 to 59.78 µg/mL, while the Daqing River shows the lowest concentrations, ranging from 15.79 to 17.48 µg/mL. LREEs (La to Nd) predominate with a total concentration of 23.501 µg/mL, leading to a notable LREE/HREE ratio of 7.901. Positive Ce anomalies (0.70-1.11) and strong positive Eu anomalies (1.38-2.49) were observed. The study suggests that the Beijing water system's REEs may originate from geological and anthropogenic sources, such as mining and industrial activities in neighboring regions, including Inner Mongolia. These findings underscore the importance of ongoing monitoring and effective water management strategies to address REE-related environmental concerns.


Asunto(s)
Monitoreo del Ambiente , Metales de Tierras Raras , Ríos , Contaminantes Químicos del Agua , Metales de Tierras Raras/análisis , Monitoreo del Ambiente/métodos , Ríos/química , Contaminantes Químicos del Agua/análisis , Beijing , China , Fraccionamiento Químico
5.
Small ; 19(38): e2301019, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37209021

RESUMEN

Type 1 diabetes (T1D), which is a chronic autoimmune disease, results from the destruction of insulin-producing ß cells targeted by autoreactive T cells. The recent discovery that mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) function as therapeutic tools for autoimmune conditions has attracted substantial attention. However, the in vivo distribution and therapeutic effects of MSC-EVs potentiated by pro-inflammatory cytokines in the context of T1D have yet to be established. Here, it is reported that hexyl 5-aminolevulinate hydrochloride (HAL)-loaded engineered cytokine-primed MSC-EVs (H@TI-EVs) with high expression of immune checkpoint molecule programmed death-legend 1 (PD-L1) exert excellent inflammatory targeting and immunosuppressive effects for T1D imaging and therapy. The accumulated H@TI-EVs in injured pancreas not only enabled the fluorescence imaging and tracking of TI-EVs through the intermediate product protoporphyrin (PpIX) generated by HAL, but also promoted the proliferative and anti-apoptotic effects of islet ß cells. Further analysis revealed that H@TI-EVs exhibited an impressive ability to reduce CD4+ T cell density and activation through the PD-L1/PD-1 axis, and induced M1-to-M2 macrophage transition to reshape the immune microenvironment, exhibiting high therapeutic efficiency in mice with T1D. This work identifies a novel strategy for the imaging and treatment of T1D with great potential for clinical application.


Asunto(s)
Diabetes Mellitus Tipo 1 , Vesículas Extracelulares , Animales , Ratones , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/terapia , Antígeno B7-H1/metabolismo , Vesículas Extracelulares/metabolismo , Linfocitos T/metabolismo , Ácido Hialurónico
6.
Semin Neurol ; 42(3): 363-374, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35835448

RESUMEN

In recent years, neuroimaging studies have remarkably demonstrated the presence of cognitive motor dissociation in patients with disorders of consciousness (DoC). These findings accelerated the development of brain-computer interfaces (BCIs) as clinical tools for behaviorally unresponsive patients. This article reviews the recent progress of BCIs in patients with DoC and discusses the open challenges. In view of the practical application of BCIs in patients with DoC, four aspects of the relevant literature are introduced: consciousness detection, auxiliary diagnosis, prognosis, and rehabilitation. For each aspect, the paradigm design, brain signal processing methods, and experimental results of representative BCI systems are analyzed. Furthermore, this article provides guidance for BCI design for patients with DoC and discusses practical challenges for future research.


Asunto(s)
Interfaces Cerebro-Computador , Estado de Conciencia , Trastornos de la Conciencia/diagnóstico , Electroencefalografía , Humanos , Pronóstico
7.
Theor Appl Genet ; 134(8): 2469-2479, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33987716

RESUMEN

KEY MESSAGE: Powdery mildew resistance gene MlIW39, originated from wild emmer wheat accession IW39, was mapped to a 460.3 kb genomic interval on wheat chromosome arm 2BS. Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is destructive disease and a significant threat to wheat production globally. The most effective way to control this disease is genetic resistance. However, when resistance genes become widely deployed in agriculture, their effectiveness is compromised by virulent variants that were previously minor components of the pathogen population or that arise from mutation. This necessitates continual search for new sources of resistance in both wheat and its near relatives. In this study, we produced a common wheat line 8D49 (87-1/IW39//2*87-1), which has all-stage immunity to Bgt isolate E09 and many other Chinese Bgt isolates, by transferring powdery mildew resistance from Israeli wild emmer wheat (WEW) accession IW39 to the susceptible common wheat line 87-1. Genetic analysis indicated that the powdery mildew resistance in 8D49 was controlled by a single dominant gene, temporarily designated MlIW39. Genetic linkage analyses with molecular markers showed that MlIW39 was located in a 0.7 cm genetic region between markers QB-3-16 and 7Seq546 on the short arm of chromosome 2B. Fine mapping using three large F2 populations delimited MlIW39 to a physical interval of approximately 460.3 kb region in the WEW reference genome (Zavitan v1.0) that contained six annotated protein-coding genes, four of which had gene structures similar to known disease resistance genes. This provides a foundation for map-based cloning of MlIW39. Markers 7Seq622 and 7Seq727 co-segregating with MlIW39 can be utilized for marker-assisted selection in further genetic studies and wheat breeding.


Asunto(s)
Ascomicetos/fisiología , Mapeo Cromosómico/métodos , Cromosomas de las Plantas/genética , Resistencia a la Enfermedad/inmunología , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/metabolismo , Triticum/genética , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Triticum/crecimiento & desarrollo , Triticum/microbiología
8.
Sensors (Basel) ; 21(24)2021 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-34960409

RESUMEN

N,N,N',N'-Tetraoctyl diglycolamide (TODGA), as a new extraction agent, is effective for its excellent performance and low environmental hazard, and it is very welcome for the rare earth separation process. In this paper, by controlling the extraction time, diluent type, acid type and its concentration, rare earth concentration, etc., the optimum extraction and back-extraction effects of TODGA on La(III), Ce(III), Pr(III), and Nd(III) and mixed rare earths were obtained. The experiment showed that 0.10 mol·L-1 TODGA had the best extraction effect on single rare earth under the conditions of using petroleum ether as diluent, 5 mol·L-1 nitric acid, 20 min extraction time, and 0.01 mol·L-1 rare earth. In the mixed rare earth extraction, the percentage concentrations of La(III), Ce(III), Pr(III), and Nd(III) could be achieved from 21.7%, 19.9%, 30.8%, and 22.2% at the initial stage to 90.5%, 37%, 51%, and 62% after extraction, respectively, by controlling the number of back-extraction cycles and the concentrations of hydrochloric acid and nitric acid in the back-extraction system. The TODGA-rare earth carrier system showed the best back-extraction effect when the hydrochloric acid concentration was 1 mol·L-1 and the back-extraction time was 20 min. At the same time, the mixed rare earth liquid system with low initial concentration was selected for extraction and separation of mixed rare earth. The separation effect was better, and the recovery rate was higher than that of mixed rare earth liquid system with a high initial concentration.


Asunto(s)
Metales de Tierras Raras , Solventes
9.
Sensors (Basel) ; 20(11)2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32471047

RESUMEN

:Electroencephalogram (EEG) signals have been widely used in emotion recognition. However, the current EEG-based emotion recognition has low accuracy of emotion classification, and its real-time application is limited. In order to address these issues, in this paper, we proposed an improved feature selection algorithm to recognize subjects' emotion states based on EEG signal, and combined this feature selection method to design an online emotion recognition brain-computer interface (BCI) system. Specifically, first, different dimensional features from the time-domain, frequency domain, and time-frequency domain were extracted. Then, a modified particle swarm optimization (PSO) method with multi-stage linearly-decreasing inertia weight (MLDW) was purposed for feature selection. The MLDW algorithm can be used to easily refine the process of decreasing the inertia weight. Finally, the emotion types were classified by the support vector machine classifier. We extracted different features from the EEG data in the DEAP data set collected by 32 subjects to perform two offline experiments. Our results showed that the average accuracy of four-class emotion recognition reached 76.67%. Compared with the latest benchmark, our proposed MLDW-PSO feature selection improves the accuracy of EEG-based emotion recognition. To further validate the efficiency of the MLDW-PSO feature selection method, we developed an online two-class emotion recognition system evoked by Chinese videos, which achieved good performance for 10 healthy subjects with an average accuracy of 89.5%. The effectiveness of our method was thus demonstrated.


Asunto(s)
Interfaces Cerebro-Computador , Electroencefalografía , Emociones/clasificación , Algoritmos , Humanos , Máquina de Vectores de Soporte
10.
Int J Mol Sci ; 21(2)2020 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-31968554

RESUMEN

Our previous study indicated that glycerol application induced resistance to powdery mildew (Bgt) in wheat by regulating two important signal molecules, glycerol-3-phosphate (G3P) and oleic acid (OA18:1). Transcriptome analysis of wheat leaves treated by glycerol and inoculated with Bgt was performed to identify the activated immune response pathways. We identified a set of differentially expressed transcripts (e.g., TaGLI1, TaACT1, and TaSSI2) involved in glycerol and fatty acid metabolism that were upregulated in response to Bgt infection and might contribute to G3P and OA18:1 accumulation. Gene Ontology (GO) enrichment analysis revealed GO terms induced by glycerol, such as response to jasmonic acid (JA), defense response to bacterium, lipid oxidation, and growth. In addition, glycerol application induced genes (e.g., LOX, AOS, and OPRs) involved in the metabolism pathway of linolenic and alpha-linolenic acid, which are precursor molecules of JA biosynthesis. Glycerol induced JA and salicylic acid (SA) levels, while glycerol reduced the auxin (IAA) level in wheat. Glycerol treatment also induced pathogenesis related (PR) genes, including PR-1, PR-3, PR-10, callose synthase, PRMS, RPM1, peroxidase, HSP70, HSP90, etc. These results indicate that glycerol treatment regulates fatty acid metabolism and hormones cross-talk and induces the expression of PR genes that together contribute to Bgt resistance in wheat.


Asunto(s)
Ascomicetos/fisiología , Resistencia a la Enfermedad , Ácidos Grasos/metabolismo , Glicerol/farmacología , Enfermedades de las Plantas/inmunología , Reguladores del Crecimiento de las Plantas/metabolismo , Triticum/inmunología , Ciclopentanos/metabolismo , Perfilación de la Expresión Génica , Oxilipinas/metabolismo , Enfermedades de las Plantas/microbiología , Hojas de la Planta/genética , Hojas de la Planta/inmunología , Hojas de la Planta/microbiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Triticum/genética , Triticum/microbiología
11.
Opt Express ; 27(15): 21226-21238, 2019 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-31510204

RESUMEN

In this paper, a novel composite metasurface (MS) with diffuse scattering and absorbing characteristics is proposed to reduce the radar cross section (RCS) of a metal target in a broad band. The combination of absorption and diffusion is realized based on lossy Pancharatnam-Berry (PB) phase particles. The units are arranged according to a coding sequence which is obtained by an optimization algorithm based on simulated annealing algorithm. Simulation results show that the MS obtained based on the optimized coding sequence is insensitive to polarization. Due to the combination of absorption and diffusion, the MS has good performance in both monostatic and bistatic scenarios. Finally, the proposed MS is fabricated and measured, and the experimental results are in good agreement with simulation results. A 10 dB backward reflection reduction can be achieved from 21GHz to 38GHz and a 15 dB backward reflection reduction can be achieved from 22GHz to 35GHz under normal incidence. Furthermore, the MS has good performance under large angle (<45°) incidence.

12.
J Stroke Cerebrovasc Dis ; 25(7): 1713-1720, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27083069

RESUMEN

BACKGROUND: The predictive value of neurophysiologic assessment on patients' outcome after acute cerebral infarction is poorly understood. The aim of this study was to investigate the prognostic value of motor-evoked potentials (MEPs) and the silent period (SP) on clinical outcome. METHODS: A total of 202 patients with acute cerebral infarction were prospectively recruited. MEP and SP were recorded from the abductor pollicis brevis of the affected side within 10 days after stroke onset. Patient outcome was measured as the dependency rate. RESULTS: Cortical MEP was induced in 78 patients whereas it was absent in 82 patients. The initial NIHSS (National Institutes of Health Stroke Scale) score was significantly lower in patients with MEP than in those without MEP (P < .001). Regression analysis demonstrated that a left-sided lesion (OR = .391, 95% CI .178-.858, P = .019), NIHSS at admission (OR = .826, 95% CI .744-.917, P < .001), and presence of MEP (OR = 3.918, 95% CI 1.770-8.672, P < .001) were independent predictors of outcome 3 months after stroke. Among patients with MEP, only the contralateral cortical SP value was significantly shorter in the good outcome subgroup (t = 2.541, P = .013). Receiver operating characteristic curve analysis demonstrated that SP was able to predict patients at higher risk of unfavorable outcome 3 months after stroke onset (area under the curve .721, 95% CI .58-.86, P = .008). CONCLUSIONS: These data suggested that MEP and SP were useful tools to predict patients' acute outcomes following cerebral infarction.


Asunto(s)
Infarto Cerebral/diagnóstico , Electromiografía , Potenciales Evocados Motores , Actividad Motora , Corteza Motora/fisiopatología , Músculo Esquelético/inervación , Estimulación Magnética Transcraneal , Enfermedad Aguda , Anciano , Infarto Cerebral/fisiopatología , Infarto Cerebral/terapia , Distribución de Chi-Cuadrado , Evaluación de la Discapacidad , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Valor Predictivo de las Pruebas , Estudios Prospectivos , Recuperación de la Función , Sistema de Registros , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
13.
J Stroke Cerebrovasc Dis ; 24(6): 1145-52, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25869773

RESUMEN

High residual platelet reactivity (HRPR) assessed by multiple tests has been associated with worse clinical outcomes. However, the clinical impact of HRPR assessed by flow cytometry is unknown. The aim of this study was to validate the predictive value of HRPR measured by flow cytometry for clinical outcomes in ischemic stroke patients during clopidogrel therapy. Overall, 198 consecutive patients with ischemic stroke taking clopidogrel underwent platelet function testing on flow cytometer including adenosine diphosphate (ADP)-induced platelet aggregation (PAg) and platelet activation markers (CD62P, CD63, and PAC-1). Poor outcome was defined as poor prognosis and ischemic events during 12-month follow-up. By receiver operating characteristic curve analysis, residual platelet reactivity assessed by flow cytometry was able to distinguish between patients with and without poor outcomes, when platelet inhibition was evaluated with ADP-PAg (area under the curve [AUC], .77; 95% confidence interval [CI], .69-.84; P < .001), CD62P (AUC, .73; 95% CI, .64-.81; P < .001), CD63 (AUC, .72; 95% CI, .64-.80; P < .001), and PAC-1 (AUC, .70; 95% CI, .62-.78; P < .001). The prevalence of HRPR was 25.8% for ADP-PAg, 32.8% for CD62P, 41.4% for CD63, and 56.1% for PAC-1. The multiple logical regression analysis demonstrated that HRPR was an independent predictor of poor outcomes (ADP-PAg: odds ratio [OR] 13.03, 95% CI 5.66-29.98, P < .001; CD62P: OR 8.55, 95% CI 3.94-18.57, P < .001; CD63: OR 8.74, 95% CI 3.89-19.64, P < .001; PAC-1: OR 4.23, 95% CI 1.98-9.08). In conclusion, HRPR, assessed by flow cytometry, is able to detect ischemic stroke patients at increased risk of 12-month poor outcomes on clopidogrel treatment.


Asunto(s)
Plaquetas/efectos de los fármacos , Isquemia Encefálica/sangre , Activación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/farmacología , Accidente Cerebrovascular/sangre , Ticlopidina/análogos & derivados , Anciano , Anciano de 80 o más Años , Clopidogrel , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Agregación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Pruebas de Función Plaquetaria , Ticlopidina/farmacología , Ticlopidina/uso terapéutico
14.
J Environ Sci (China) ; 28: 8-13, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25662232

RESUMEN

In recent years, Dechloranes have been widely detected in the environment around the world. However, understanding and knowledge of Dechloranes in remote regions, such as the Arctic, remain lacking. Therefore, the concentrations of 5 Dechloranes in surface seawater, sediment, soil, moss, and dung collected from Ny-Ålesund in the Arctic were measured with the concentrations 93 pg/L, 342, 325, 1.4, and 258 pg/g, respectively, which were much lower than those in Asian and European regions. The mean ratios of anti-Dechlorane Plus (DP) to total DP (ƒanti) in seawater, sediment, soil, moss, dung, and atmospheric samples were 0.36, 0.21, 0.18, 0.27, 0.66, and 0.43, respectively. Results suggested that the main source of DP in seawater, sediment, soil, and moss was long-range atmospheric transport. However, the ratio identified in dung was different, for which the migration behavior of the organism is probably the main source of DP.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Retardadores de Llama/análisis , Hidrocarburos Clorados/análisis , Regiones Árticas , Cromatografía de Gases y Espectrometría de Masas , Noruega
15.
Brain Sci ; 14(6)2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38928590

RESUMEN

As the population ages worldwide, Alzheimer's disease (AD), the most prevalent kind of neurodegenerative disorder among older people, has become a significant factor affecting quality of life, public health, and economies. However, the exact pathogenesis of Alzheimer's remains elusive, and existing highly recognized pathogenesis includes the amyloid cascade hypothesis, Tau neurofibrillary tangles hypothesis, and neuroinflammation hypothesis. The major diagnoses of Alzheimer's disease include neuroimaging positron emission computed tomography, magnetic resonance imaging, and cerebrospinal fluid molecular diagnosis. The therapy of Alzheimer's disease primarily relies on drugs, and the approved drugs on the market include acetylcholinesterase drugs, glutamate receptor antagonists, and amyloid-ß monoclonal antibodies. Still, the existing drugs can only alleviate the symptoms of the disease and cannot completely reverse it. This review aims to summarize existing research results on Alzheimer's disease pathogenesis, diagnosis, and drug therapy, with the objective of facilitating future research in this area.

16.
Adv Sci (Weinh) ; 11(24): e2309517, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38647405

RESUMEN

Intravenous thrombolysis with recombinant tissue plasminogen activator (rtPA) is the primary treatment for ischemic stroke. However, rtPA treatment can substantially increase blood-brain barrier (BBB) permeability and susceptibility to hemorrhagic transformation. Herein, the mechanism underlying the side effects of rtPA treatment is investigated and demonstrated that ferroptosis plays an important role. The ferroptosis inhibitor, liproxstatin-1 (Lip) is proposed to alleviate the side effects. A well-designed macrocyclic carrier, glucose-modified azocalix[4]arene (GluAC4A), is prepared to deliver Lip to the ischemic site. GluAC4A bound tightly to Lip and markedly improved its solubility. Glucose, modified at the upper rim of GluAC4A, imparts BBB targeting to the drug delivery system owing to the presence of glucose transporter 1 on the BBB surface. The responsiveness of GluAC4A to hypoxia due to the presence of azo groups enabled the targeted release of Lip at the ischemic site. GluAC4A successfully improved drug accumulation in the brain, and Lip@GluAC4A significantly reduced ferroptosis, BBB leakage, and neurological deficits induced by rtPA in vivo. These findings deepen the understanding of the side effects of rtPA treatment and provide a novel strategy for their effective mitigation, which is of great significance for the treatment and prognosis of patients with ischemic stroke.


Asunto(s)
Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Ferroptosis , Accidente Cerebrovascular Isquémico , Activador de Tejido Plasminógeno , Animales , Ferroptosis/efectos de los fármacos , Ratones , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Activador de Tejido Plasminógeno/farmacología , Activador de Tejido Plasminógeno/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Masculino , Quinoxalinas , Compuestos de Espiro
17.
Micromachines (Basel) ; 14(5)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37241587

RESUMEN

In the realm of automatic wire-traction micromanipulation systems, the alignment of the central axis of the coil with the rotation axis of the rotary stage can be a challenge, which leads to the occurrence of eccentricity during rotation. The wire-traction is conducted at a micron-level of manipulation precision on micron electrode wires; eccentricity has a significant impact on the control accuracy of the system. To resolve the problem, a method for measuring and correcting the coil eccentricity is proposed in this paper. First, models of radial and tilt eccentricity are established respectively based on the eccentricity sources. Then, measuring eccentricity is proposed by an eccentricity model and microscopic vision; the model is used to predict eccentricity, and visual image processing algorithms are used to calibrate model parameters. In addition, a correction based on the compensation model and hardware is designed to compensate for the eccentricity. The experimental results demonstrate the accuracy of the models in predicting eccentricity and the effectiveness of correction. The results show that the models have an accurate prediction for eccentricity that relies on the evaluation of the root mean square error (RMSE); the maximal residual error after correction was within 6 µm, and the compensation was approximately 99.6%. The proposed method, which combines the eccentricity model and microvision for measuring and correcting eccentricity, offers improved wire-traction micromanipulation accuracy, enhanced efficiency, and an integrated system. It has more suitable and wider applications in the field of micromanipulation and microassembly.

18.
Materials (Basel) ; 16(7)2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37049190

RESUMEN

Microbiologically influenced corrosion (MIC) is a common phenomenon in water treatment, shipping, construction, marine and other industries. Sulfate-reducing bacteria (SRB) often lead to MIC. In this paper, a strain of Pseudomonas stutzeri (P. stutzeri) with the ability to inhibit SRB corrosion is isolated from the soil through enrichment culture. P. stutzeri is a short, rod-shaped, white and transparent colony with denitrification ability. Our 16SrDNA sequencing results verify the properties of P. stutzeri strains. The growth conditions of P. stutzeri bacteria and SRB are similar, and the optimal culture conditions are about 30 °C, pH 7, and the stable stage is reached in about seven days. The bacteria can coexist in the same growth environment. Using the weight loss method, electrochemical experiments and composition analysis techniques we found that P. stutzeri can inhibit the corrosion of X70 steel by SRB at 20~40 °C, pH 6~8. Furthermore, long-term tests at 3, 6 and 9 months reveal that P. stutzeri can effectively inhibit the corrosion of X70 steel caused by SRB.

19.
Plant Physiol Biochem ; 205: 108207, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38006791

RESUMEN

The bHLH family, the second largest transcription factor (TF) family in plants, plays a crucial role in regulating plant growth and development processes. However, the biological functions and mechanisms of most bHLH proteins remain unknown, particularly in apples. In this study, we found that MdbHLH4 positively modulates plant growth and development by enhancing cell expansion. Overexpression (OE) of MdbHLH4 resulted in increased biomass, stem and root length, leaf area, and larger areas of pith, xylem, and cortex with greater cell size compared with wild-type apple plants. Conversely, RNA interference (RNAi)-mediated silencing of MdbHLH4 led to reduced xylem and phloem as well as smaller cell size compared to wild-type apple plants. Ectopic expression of MdbHLH4 in tomatoes resulted in enlarged fruits with impaired color appearance, decreased accumulation of soluble solids, and decreased flesh firmness along with larger seeds. Subsequent investigations have shown that MdbHLH4 directly binds to the promoters of MdARF6b and MdPIF4b, enhancing their expression levels. These findings suggest that MdbHLH4 potentially regulates plant cell expansion through auxin and light signaling pathways. These study results not only provide new insights into the roles of bHLH transcription factors in regulating plant growth and development but also contribute to a deeper understanding of their underlying mechanisms.


Asunto(s)
Malus , Malus/metabolismo , Factores de Transcripción/genética , Frutas/metabolismo , Aumento de la Célula , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo
20.
Mar Pollut Bull ; 191: 114916, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37058831

RESUMEN

This study reviewed the content and distribution of rare earth elements (REE) in rivers and lakes in China based on the online literature. The sequence distribution of REE presented the decreasing trends in the order: of Ce > La > Nd > Pr > Sm > Gb > Dy>Er > Yb > Eu > Lu > Ho > Tb > Tm in rivers water. Pearl River and the Jiulong River constitute a significant sediments REE reservoir with an average value mean of 229.6 mg/kg and 266.86 mg/kg, respectively; both have higher concentrations than the global river average (174.8 mg/kg) and higher than the local soil background (Chinese soil background). The Liaohe River is one of China's most polluted rivers, with REE distribution ranging from 106.61 to 174.71 g/L (average 144.59 g/L in water). The total concentrations of dissolved REE in rivers near REE mining areas in China are higher than in other rivers. Increasing anthropogenic inputs to natural systems may permanently alter the natural signatures of REE. The distribution characteristics of REE in Chinese lakes (sediments) varied greatly, and the mean enrichment factor (EF) was sorted as follows: Ce > La > Nd > Pr > Sm > Gd > Dy>Er > Yb > Eu > Ho > Tb > Tm > Lu, where Ce was the most abundant followed by La, Nd, and Pr, and these four elements account for 85.39 % of the total concentration of REE. The REE in the sediments obtained from Poyang Lake and Dongting Lake had an average concentration respectively of 254.0 µg/g and 197.95 µg/g; both are considerably higher than the average upper continental crust (146.4 µg/g) and higher than in other lakes in China and around the world. The distribution and accumulation of LREE in most lake sediments result from the joint action of human activities and natural processes. It concluded that mining tailings were the primary cause of REE pollution in sediments, and industrial and agricultural activities are mainly responsible for water contamination.


Asunto(s)
Lagos , Metales de Tierras Raras , Humanos , Ríos , Monitoreo del Ambiente , Metales de Tierras Raras/análisis , Suelo , China , Agua
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