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1.
Genes Dev ; 34(3-4): 166-178, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31919188

RESUMEN

Oocytes are indispensable for mammalian life. Thus, it is important to understand how mature oocytes are generated. As a critical stage of oocytes development, meiosis has been extensively studied, yet how chromatin remodeling contributes to this process is largely unknown. Here, we demonstrate that the ATP-dependent chromatin remodeling factor Snf2h (also known as Smarca5) plays a critical role in regulating meiotic cell cycle progression. Females with oocyte-specific depletion of Snf2h are infertile and oocytes lacking Snf2h fail to undergo meiotic resumption. Mechanistically, depletion of Snf2h results in dysregulation of meiosis-related genes, which causes failure of maturation-promoting factor (MPF) activation. ATAC-seq analysis in oocytes revealed that Snf2h regulates transcription of key meiotic genes, such as Prkar2b, by increasing its promoter chromatin accessibility. Thus, our studies not only demonstrate the importance of Snf2h in oocyte meiotic resumption, but also reveal the mechanism underlying how a chromatin remodeling factor can regulate oocyte meiosis.


Asunto(s)
Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Ensamble y Desensamble de Cromatina/genética , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Factor Promotor de Maduración/genética , Meiosis/genética , Oogénesis/genética , Animales , Femenino , Regulación del Desarrollo de la Expresión Génica , Técnicas de Inactivación de Genes , Mesotelina , Ratones , Oocitos/citología , Transcriptoma
2.
Proc Natl Acad Sci U S A ; 121(38): e2409436121, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39264742

RESUMEN

In rivers, the addition of finer sediment to a coarser riverbed is known to increase the mobility of the coarser fraction. Two mechanisms have been suggested for this: a geometric mechanism whereby smaller sizes smooth the bed, increasing near-bed velocity and thus mobility of the larger sizes, and a viscous mechanism whereby a transitionally smooth turbulent boundary layer forms, rendering the coarser grains more mobile. Here, we report on experiments using two sediment mixtures to better understand these proposed mechanisms. In Mixture 1, we used 0.5 and 5 mm grains, and in Mixture 2, we used 2 and 20 mm grains. If the entrainment of coarse gravel by finer sediment is a purely geometric effect, then the addition of finer material should produce the same effect on the mobility of the coarser material for both mixtures because they have the same size ratio. We show that addition of finer material has a different effect on the two mixtures. We observed an increase in the mobility of the coarse fraction for both mixtures, but the increase in coarse fraction mobility for Mixture 1 was almost twice that for Mixture 2. Our experiments show that in addition to the geometric effect, enhancement of coarse gravel transport by finer sediment is also driven by a viscous effect.

3.
Proc Natl Acad Sci U S A ; 119(30): e2101384119, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35858402

RESUMEN

During its 6,300-km course from the Tibetan Plateau to the ocean, the Yangtze River is joined by two large lakes: Dongting Lake and Poyang Lake. We explain why these lakes exist. Deglaciation forced the ocean adjacent to the Yangtze mouth to rise ∼120 m. This forced a wave of rising water surface elevation and concomitant bed aggradation upstream. While aggradation attenuated upstream, the low bed slope of the Middle-Lower Yangtze River (∼2 × 10-5 near Wuhan) made it susceptible to sea level rise. The main stem, sourced at 5,054 m above sea level, had a substantial sediment load to "fight" against water surface level rise by means of bed aggradation. The tributaries of the Middle-Lower Yangtze have reliefs of approximately hundreds of meters, and did not have enough sediment supply to fill the tributary accommodation space created by main-stem aggradation. We show that the resulting tributary blockage likely gave rise to the lakes. We justify this using field data and numerical modeling, and derive a dimensionless number capturing the critical rate of water surface rise for blockage versus nonblockage.

4.
Proc Natl Acad Sci U S A ; 117(26): 14730-14737, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32541032

RESUMEN

Incising rivers may be confined by low-slope, erodible hillslopes or steep, resistant sidewalls. In the latter case, the system forms a canyon. We present a morphodynamic model that includes the essential elements of a canyon incising into a plateau, including 1) abrasion-driven channel incision, 2) migration of a canyon-head knickpoint, 3) sediment feed from an alluvial channel upstream of the knickpoint, and 4) production of sediment by sidewall collapse. We calculate incision in terms of collision of clasts with the bed. We calculate knickpoint migration using a moving-boundary formulation that allows a slope discontinuity where the channel head meets an alluvial plateau feeder channel. Rather than modeling sidewall collapse events, we model long-term behavior using a constant sidewall slope as the channel incises. Our morphodynamic model specifically applies to canyon, rather than river-hillslope evolution. We implement it for Rainbow Canyon, CA. Salient results are as follows: 1) Sediment supply from collapsing canyon sidewalls can be substantially larger than that supplied from the feeder channel on the plateau. 2) For any given quasi-equilibrium canyon bedrock slope, two conjugate slopes are possible for the alluvial channel upstream, with the lower of the two corresponding to a substantially lower knickpoint migration rate and higher preservation potential. 3) Knickpoint migration occurs at a substantially faster time scale than regrading of the bedrock channel itself, underlying the significance of disequilibrium processes. Although implemented for constant climactic conditions, the model warrants extension to long-term climate variation.

5.
Proc Natl Acad Sci U S A ; 117(1): 171-176, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31852827

RESUMEN

Fine-grained sediment (grain size under 2,000 µm) builds floodplains and deltas, and shapes the coastlines where much of humanity lives. However, a universal, physically based predictor of sediment flux for fine-grained rivers remains to be developed. Herein, a comprehensive sediment load database for fine-grained channels, ranging from small experimental flumes to megarivers, is used to find a predictive algorithm. Two distinct transport regimes emerge, separated by a discontinuous transition for median bed grain size within the very fine sand range (81 to 154 µm), whereby sediment flux decreases by up to 100-fold for coarser sand-bedded rivers compared to river with silt and very fine sand beds. Evidence suggests that the discontinuous change in sediment load originates from a transition of transport mode between mixed suspended bed load transport and suspension-dominated transport. Events that alter bed sediment size near the transition may significantly affect fluviocoastal morphology by drastically changing sediment flux, as shown by data from the Yellow River, China, which, over time, transitioned back and forth 3 times between states of high and low transport efficiency in response to anthropic activities.

6.
IUBMB Life ; 73(2): 398-407, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33372372

RESUMEN

Glioblastoma multiforme (GBM) is among the most common adult brain tumors with invariably fatal character. Following the limited conventional therapies, almost all patients, however, presented with symptoms at the time of recurrence. It is dire to develop novel therapeutic strategies to improve the current treatment of GBM. Gallic acid is a well-established antioxidant, presenting a promising new selective anti-cancer drug, while gold nanoparticles (GNPs) can be developed as versatile nontoxic carriers for anti-cancer drug delivery. Here, we prepared gallic acid-GNPs (GA-GNPs) by loading gallic acid onto GNPs, reduction products of tetrachloroauric acid by sodium citrate, through physical and agitation adsorption. GA-GNPs, rather than GNPs alone, significantly inhibited the survival of U251 GBM cells, as well as enhanced radiation-induced cell death. Moreover, GA-GNPs plus radiation arrested the cell cycle of U251 at the S and G2/M phases and triggered apoptotic cell death, which is supported by increased BAX protein levels and decreased expression of BCL-2. Thus, GA-GNPs have great potential in the combination with radiation therapy in future studies for GBM treatment.


Asunto(s)
Muerte Celular , Ácido Gálico/farmacología , Rayos gamma , Glioma/radioterapia , Oro/química , Nanopartículas del Metal/administración & dosificación , Fármacos Sensibilizantes a Radiaciones/farmacología , Apoptosis , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Ciclo Celular , Sistemas de Liberación de Medicamentos , Ácido Gálico/química , Glioma/tratamiento farmacológico , Glioma/patología , Humanos , Nanopartículas del Metal/química , Fármacos Sensibilizantes a Radiaciones/química , Células Tumorales Cultivadas
7.
Neoplasma ; 68(6): 1147-1156, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34427100

RESUMEN

The cystine/glutamate antiporter xCT (SLC7A11) is frequently upregulated in many cancers, including glioblastoma (GBM). SLC7A11-mediated cystine taken up is reduced to cysteine, a precursor amino acid for glutathione synthesis and antioxidant cellular defense. However, little is known about the biological functions of SLC7A11 and its effect on therapeutic response in GBM. Here, we report that the expression of SLC7A11 is higher in GBM compared with normal brain tissue, but is negatively associated with tumor grades and positively impacts survival in the bioinformatic analysis of TCGA and CGGA database. Additionally, a negative association between SLC7A11 and mismatch repair (MMR) gene expression was identified by Pearson correlation analysis. In the GBM cells with glucose-limited culture conditions, overexpression of SLC7A11 significantly decreased MMR gene expression, including MLH1, MSH6, and EXO1. SLC7A11-overexpressed GBM cells demonstrated elevated double-strand break (DSB) levels and increased sensitivity to radiation treatment. Taken together, our work indicates that SLC7A11 might be a potential biomarker for predicting a better response to radiotherapy in GBM.


Asunto(s)
Sistema de Transporte de Aminoácidos y+ , Reparación de la Incompatibilidad de ADN , Glioblastoma , Sistema de Transporte de Aminoácidos y+/genética , Sistema de Transporte de Aminoácidos y+/metabolismo , Línea Celular Tumoral , Expresión Génica , Glioblastoma/genética , Glioblastoma/radioterapia , Glucosa , Humanos
8.
Nature ; 510(7505): 397-401, 2014 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-24828042

RESUMEN

Metabolism and ageing are intimately linked. Compared with ad libitum feeding, dietary restriction consistently extends lifespan and delays age-related diseases in evolutionarily diverse organisms. Similar conditions of nutrient limitation and genetic or pharmacological perturbations of nutrient or energy metabolism also have longevity benefits. Recently, several metabolites have been identified that modulate ageing; however, the molecular mechanisms underlying this are largely undefined. Here we show that α-ketoglutarate (α-KG), a tricarboxylic acid cycle intermediate, extends the lifespan of adult Caenorhabditis elegans. ATP synthase subunit ß is identified as a novel binding protein of α-KG using a small-molecule target identification strategy termed drug affinity responsive target stability (DARTS). The ATP synthase, also known as complex V of the mitochondrial electron transport chain, is the main cellular energy-generating machinery and is highly conserved throughout evolution. Although complete loss of mitochondrial function is detrimental, partial suppression of the electron transport chain has been shown to extend C. elegans lifespan. We show that α-KG inhibits ATP synthase and, similar to ATP synthase knockdown, inhibition by α-KG leads to reduced ATP content, decreased oxygen consumption, and increased autophagy in both C. elegans and mammalian cells. We provide evidence that the lifespan increase by α-KG requires ATP synthase subunit ß and is dependent on target of rapamycin (TOR) downstream. Endogenous α-KG levels are increased on starvation and α-KG does not extend the lifespan of dietary-restricted animals, indicating that α-KG is a key metabolite that mediates longevity by dietary restriction. Our analyses uncover new molecular links between a common metabolite, a universal cellular energy generator and dietary restriction in the regulation of organismal lifespan, thus suggesting new strategies for the prevention and treatment of ageing and age-related diseases.


Asunto(s)
Caenorhabditis elegans/efectos de los fármacos , Ácidos Cetoglutáricos/farmacología , Longevidad/fisiología , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Animales , Línea Celular , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Células Jurkat , Longevidad/efectos de los fármacos , Longevidad/genética , Ratones , ATPasas de Translocación de Protón Mitocondriales/genética , Unión Proteica
9.
J Liposome Res ; 29(1): 86-93, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29671386

RESUMEN

This study aimed to develop novel temperature-sensitive liposomes loading paclitaxel (PTX-TSL) and evaluate them in vitro to improve the delivery efficiency and targeting of PTX. K237 peptide was conjugated to the terminal NHS of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[hydroxyl succinimidyl (polyethylene glycol)-(DSPE-PEG-NHS), and K237-modified PTX-TSL (K237-PTX-TSL) was prepared using a film dispersion method. K237-TSL encapsulation with calcein was synthesized and used to determine the cellular uptake of TSL. The morphology of K237-PTX-TSL was observed using a transmission electron microscope. The particle size and potential were measured using a laser particle size analyzer. The phase transition temperature was detected using the differential scanning calorimetry. The Cell Counting Kit-8 assay and flow cytometry were used to evaluate the effects of K237-PTX-TSL on the proliferation and cell cycle of cell lines SKOV-3 and human umbilical vein endothelial cell (HUVEC). The encapsulation efficiency of K237-PTX-TSL was 94.23% ± 0.76%. The particle diameter was 88.3 ± 4.7 nm. K237-PTX-TSL showed a fast release profile at 42 °C, while it was stable at 37 °C. PTX-TSL combined with hyperthermia significantly inhibited the cell proliferation of SKOV-3 cells and HUVECs due to increased cell arrest in the G2/M phase. The half-minimal inhibitory concentration value of K237-PTX-TSL on SKOV-3 cells and HUVECs was 13.61 ± 1.81 and 5.54 ± 0.95 nmol/L, respectively, which were significantly lower than those with PTX-TSL (p < 0.01). K237 modification could increase the targeting efficiency of TSL to cancer cells and vascular endothelial cells, thus resulting in higher cytotoxicities compared with PTX-TSL, which might be a potential formulation for targeting cancer therapy.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Liposomas , Oligopéptidos , Paclitaxel/administración & dosificación , Animales , Línea Celular , Humanos , Liposomas/química , Fosfatidiletanolaminas , Polietilenglicoles , Temperatura de Transición
10.
Chem Pharm Bull (Tokyo) ; 65(3): 229-235, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28250344

RESUMEN

Postoperative pain is a complex physiological response to disease and tissue injury. Moderate-to-severe pain typically occurs within 48 h after surgery. Amino amide local anesthetics are widely applied to manage postoperative pain, and they have high efficacy, a low risk for addiction and limited side effects. However, these anesthetics also have short half-lives, often necessitating continuous injection to obtain satisfactory pain relief. In the current work, we used a poly(lactic-co-glycolic acid) (PLGA)-polyethylene glycol (PEG)-PLGA (PLGA-PEG-PLGA) temperature-sensitive gel to deliver a local anesthetic, ropivacaine hydrochloride (RP), to prolong its analgesic effect. We investigated the influence of polymer and drug concentration on gelation temperature and the in vitro drug release rate from the temperature-sensitive gel. RP-loaded PLGA-PEG-PLGA solution is a liquid at room temperature and forms a gel at temperatures slightly lower than body temperature. With regard to the gel's drug release rate, 37.5, 51.3 and 72.6% of RP was released at 12, 24 and 48 h, respectively. This in vitro drug release profile conformed to the Higuchi equation. To assess pain control efficacy when using the gel, we evaluated the mechanical paw withdrawal reflex threshold, thermal pain threshold and incision cumulative pain scores in a rat incisional model. The results showed that the anti-pain effect of a single injection of RP-loaded gel at the incision site lasted for 48 h, which is significantly longer than the effect produced by injection of RP solution alone. The use of RP-loaded thermosensitive gels could provide a promising method for managing postoperative pain.


Asunto(s)
Amidas/administración & dosificación , Amidas/uso terapéutico , Anestésicos Locales/administración & dosificación , Anestésicos Locales/uso terapéutico , Sistemas de Liberación de Medicamentos , Dolor Postoperatorio/tratamiento farmacológico , Polietilenglicoles/química , Poliglactina 910/química , Temperatura , Amidas/química , Anestésicos Locales/química , Animales , Relación Dosis-Respuesta a Droga , Dimensión del Dolor , Dolor Postoperatorio/patología , Polietilenglicoles/administración & dosificación , Poliglactina 910/administración & dosificación , Ratas , Ratas Sprague-Dawley , Reología , Ropivacaína , Factores de Tiempo
11.
Amino Acids ; 46(5): 1177-85, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24481486

RESUMEN

Pidotimod is a synthetic dipeptide with biological and immunological activity in innate immune responses. It has been reported that pidotimod could promote functional maturation of dendritic cells, but little is known about the regulation of macrophages. Recent studies have demonstrated that M1 or M2 polarized macrophages are of great importance for responses to microorganism infection or host mediators. The aim of this study was to determine the effectiveness of pidotimod on mouse bone marrow-derived macrophage polarization and its function. The results showed that pidotimod had no influence on M1-polarized macrophage. While interestingly, a significant increase of M2 marker gene expression (Arg1, Fizz1, Ym1, MR) was observed (p < 0.01) in IL-4-induced M2 macrophage treated with pidotimod. In addition, cell surface expression of mannose receptor was dramatically enhanced using fluorescence activated cell sorter (FACS) analysis. Furthermore, the function of M2 macrophage was also determinated. The results showed that the supernatant of pidotimod-treated M2 macrophage could increase the migration (p < 0.05) and enhance the wound closure rate (p < 0.05) of MLE-12 cells. Collectively, it could be concluded that pidotimod significantly facilitated IL-4-induced M2 macrophage polarization and improves its function.


Asunto(s)
Polaridad Celular/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Péptidos/farmacología , Ácido Pirrolidona Carboxílico/análogos & derivados , Tiazolidinas/farmacología , Animales , Biomarcadores/análisis , Activación de Macrófagos/efectos de los fármacos , Macrófagos/citología , Ratones , Ratones Endogámicos C57BL , Ácido Pirrolidona Carboxílico/farmacología
12.
J Vis Exp ; (203)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38251798

RESUMEN

In this paper, the directional gradient histogram technology is employed to extract the features of concrete image samples captured under different vibration states. The support vector machine (SVM) is utilized to learn the relationship between image features and vibration state. The machine learning results are subsequently used to assess the feasibility of the concrete vibration state. Simultaneously, the influence mechanism of the calculation parameters of the directional gradient histogram on the recognition accuracy is analyzed. The results demonstrate the feasibility of using the directional gradient histogram-SVM technology to identify the vibration state of concrete. The recognition accuracy initially increases and then decreases as the block size of the directional gradient, or the number of statistical intervals increases. The recognition accuracy also decreases linearly with the increase of the binarization threshold. By using sample images with a resolution of 1024 pixels x 1024 pixels and optimizing the feature extraction parameters, a recognition accuracy of 100% can be attained.


Asunto(s)
Máquina de Vectores de Soporte , Vibración , Aprendizaje Automático , Reconocimiento en Psicología , Tecnología
13.
Polymers (Basel) ; 16(10)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38794594

RESUMEN

Polyaniline (PANI) has long been explored as a promising organic cathode for Li-ion batteries. However, its poor electrochemical utilization and cycling instability cast doubt on its potential for practical applications. In this work, we revisit the electrochemical performance of PANI in nonaqueous electrolytes, and reveal an unprecedented reversible capacity of 197.2 mAh g-1 (244.8 F g-1) when cycled in a wide potential range of 1.5 to 4.4 V vs. Li+/Li. This ultra-high capacity derives from 70% -NH- transformed to =NH+- during deep charging/discharging process. This material also demonstrates a high average coulombic efficiency of 98%, an excellent rate performance with 73.5 mAh g-1 at 1800 mA g-1, and retains 76% of initial value after 100 cycles, which are among the best reported values for PANI electrodes in battery applications.

14.
Sci Total Environ ; 921: 171099, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38387588

RESUMEN

To ensure the long-term performance of proton-exchange membrane fuel cells (PEMFCs), proton-exchange membranes (PEMs) have stringent requirements at high temperatures and humidities, as they may lose proton carriers. This issue poses a serious challenge to maintaining their proton conductivity and mechanical performance throughout their service life. Ionogels are ionic liquids (ILs) hybridized with another component (such as organic, inorganic, or organic-inorganic hybrid skeleton). This design is used to maintain the desirable properties of ILs (negligible vapor pressure, thermal stability, and non-flammability), as well as a high ionic conductivity and wide electrochemical stability window with low outflow. Ionogels have opened new routes for designing solid-electrolyte membranes, especially PEMs. This paper reviews recent research progress of ionogels in proton-exchange membranes, focusing on their electrochemical properties and proton transport mechanisms.

15.
ACS Appl Mater Interfaces ; 16(12): 15251-15261, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38489474

RESUMEN

Nowadays, the rapid development of electronic devices requires composites with high thermal conductivity and good electromagnetic shielding properties. The key challenge lies in the construction of high-performance conductive networks. Herein, an electrochemical expansion graphite foam (EEG) with a quasi-hyperbolic framework was prepared by an electrochemical expansion method, and then the epoxy resin (EP) was filled to fabricate the composites. The graphite plate was first electrochemically intercalated and then foamed, in which plasticization was caused by weak oxidation in intercalation and the quasi-hyperbolic framework was induced by foaming during expansion. These processes were characterized by Fourier transform infrared (FTIR), micro-Raman, X-ray photoelectron spectroscopy (XPS), and so on. Based on the highly efficient quasi-hyperbolic framework and high-quality graphite structure, the thermal conductivity of the composite reached 43.523 W/(m·K), and total electromagnetic interference (EMI) shielding (SET) reached 105 dB. The heat transfer behavior was simulated by finite element analysis (FEA) in detail. This method of preparing high thermal conductivity and electromagnetic shielding materials has a good application prospect.

16.
Front Hum Neurosci ; 18: 1387471, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952644

RESUMEN

Objective: This study aimed to explore the electroencephalogram (EEG) indicators and clinical factors that may lead to poor prognosis in patients with prolonged disorder of consciousness (pDOC), and establish and verify a clinical predictive model based on these factors. Methods: This study included 134 patients suffering from prolonged disorder of consciousness enrolled in our department of neurosurgery. We collected the data of sex, age, etiology, coma recovery scales (CRS-R) score, complications, blood routine, liver function, coagulation and other laboratory tests, resting EEG data and follow-up after discharge. These patients were divided into two groups: training set (n = 107) and verification set (n = 27). These patients were divided into a training set of 107 and a validation set of 27 for this study. Univariate and multivariate regression analysis were used to determine the factors affecting the poor prognosis of pDOC and to establish nomogram model. We use the receiver operating characteristic (ROC) and calibration curves to quantitatively test the effectiveness of the training set and the verification set. In order to further verify the clinical practical value of the model, we use decision curve analysis (DCA) to evaluate the model. Result: The results from univariate and multivariate logistic regression analyses suggested that an increased frequency of occurrence microstate A, reduced CRS-R scores at the time of admission, the presence of episodes associated with paroxysmal sympathetic hyperactivity (PSH), and decreased fibrinogen levels all function as independent prognostic factors. These factors were used to construct the nomogram. The training and verification sets had areas under the curve of 0.854 and 0.920, respectively. Calibration curves and DCA demonstrated good model performance and significant clinical benefits in both sets. Conclusion: This study is based on the use of clinically available and low-cost clinical indicators combined with EEG to construct a highly applicable and accurate model for predicting the adverse prognosis of patients with prolonged disorder of consciousness. It provides an objective and reliable tool for clinicians to evaluate the prognosis of prolonged disorder of consciousness, and helps clinicians to provide personalized clinical care and decision-making for patients with prolonged disorder of consciousness and their families.

17.
Water Res ; 259: 121859, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38851114

RESUMEN

Intermittent rivers in semiarid and arid regions, constituting over half of the world's rivers, alternate the carbon cycle interactions among the biosphere, hydrosphere, and atmosphere. Inadequate quantification of flow duration and river water surface area, along with overlooked CO2 emissions from dry riverbeds, result in notable inaccuracies in global carbon cycle assessments. High-resolution remote sensing images combined with intensive field measurements and hydrological modelling were used to estimate and extract the flow duration, river water surface area and dry riverbed area of Huangfuchuan, an intermittent river watershed that acts as a major tributary of the Yellow River in semiarid Northwest China. CO2 emission rates and partial pressures in water and air across the watershed were in-situ measured. In 2018, the flow duration of Huangfuchuan increased from less than 5 days in the first-order tributary to 150 days in the sixth-order mainstream. River water surface area estimated by remote sensing extraction plus the hydrodynamic model simulation varied from 3.9 to 88.6 km2 under 5 %-95 % discharge frequencies. CO2 emissions from the water-air interface and dry riverbed in 2018 were estimated at 582.3 × 103 and 355.2 × 103 ton, respectively. The estimated total annual emission (937.5 × 103 ton) aligns closely with the range of emissions (67.3 × 103-1377.2 × 103 ton) calculated for the water-air interface alone, derived using DEM river length and hydraulic geometry method. This similarity can be attributed to the overestimation of flow duration and flow velocity, as well as the over- or under-estimation of river water surface area and slope. The new method proposed in this study has large potential to be applied in estimating CO2 emissions from data-scarce intermittent rivers located in mountainous regions and provides a standardized solution in the estimation of CO2 emission. Results of this research reveal the spatiotemporal distribution of CO2 emissions along an intermittent river system and highlight the substantial role of dry riverbed in carbon cycle.


Asunto(s)
Dióxido de Carbono , Monitoreo del Ambiente , Ríos , Ríos/química , Dióxido de Carbono/análisis , Monitoreo del Ambiente/métodos , China , Ciclo del Carbono
18.
J Colloid Interface Sci ; 678(Pt B): 388-399, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39255596

RESUMEN

The traditional preparation of nanocomposite proton exchange membranes (PEM) is hindered by poor organic-inorganic interface compatibility, insufficient proton-conducting sites, easy aggregation of nanoparticles, and difficulty in leveraging nanoscale advantages. In this study, a novel method involving electrochemical anodic oxidation exfoliation was employed to prepare melamine-coated graphene oxide (Me@GO), which was subsequently subjected to in-situ polymerization with poly(2,5-benzimidazole) (ABPBI) to prepare a Me@GO/ABPBI composite proton exchange membrane. Benefiting from the strong hydrogen bonding and large π stacking interactions, melamine (Me) tightly bound to graphene oxide (GO), effectively preventing the secondary aggregation of GO after exfoliation. Moreover, the abundant alkaline functional groups of melamine enhanced the enhancement of phosphoric acid (PA) retention in the Me@GO/ABPBI membranes, thereby increasing the number of proton-conducting sites. The experimental results indicated that the introduction of Me@GO enhanced membrane properties. For Me@GO at a concentration of 1 wt%, the tensile strength of the 1Me@GO/ABPBI composite membrane reached 207 MPa, nearly 2.52 times that of the pure membrane. The proton conductivity of the 1Me@GO/ABPBI composite membrane reached 0.01 S cm-1 across a wide temperature range (40-180 °C), peaking at 0.087 S cm-1 at 180 °C. Additionally, a single-cell incorporating the 1Me@GO/ABPBI composite membrane achieved a peak power density of 0.304 W cm-2 at 160 °C, nearly 1.46 times that of the pure membrane. Benefiting from the well-dispersed and PA-enriched proton channels provided by Me@GO, the Me@GO/ABPBI composite membrane exhibits excellent prospects for wide-temperature range (40-180 °C) applications.

19.
Aging Cell ; 23(6): e14143, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38482753

RESUMEN

Hutchinson-Gilford progeria syndrome (HGPS) is a rare and fatal disease manifested by premature aging and aging-related phenotypes, making it a disease model for aging. The cellular machinery mediating age-associated phenotypes in HGPS remains largely unknown, resulting in limited therapeutic targets for HGPS. In this study, we showed that mitophagy defects impaired mitochondrial function and contributed to cellular markers associated with aging in mesenchymal stem cells derived from HGPS patients (HGPS-MSCs). Mechanistically, we discovered that mitophagy affected the aging-associated phenotypes of HGPS-MSCs by inhibiting the STING-NF-ĸB pathway and the downstream transcription of senescence-associated secretory phenotypes (SASPs). Furthermore, by utilizing UMI-77, an effective mitophagy inducer, we showed that mitophagy induction alleviated aging-associated phenotypes in HGPS and naturally aged mice. Collectively, our results uncovered that mitophagy defects mediated the aging-associated markers in HGPS, highlighted the function of mitochondrial homeostasis in HGPS progression, and suggested mitophagy as an intervention target for HGPS and aging.


Asunto(s)
Mitofagia , Progeria , Progeria/metabolismo , Progeria/genética , Progeria/patología , Mitofagia/genética , Humanos , Ratones , Animales , Envejecimiento/metabolismo , Senescencia Celular/genética
20.
Front Neurol ; 15: 1410531, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39211814

RESUMEN

Objective: Meige syndrome (MS) is an adult-onset segmental dystonia for which no satisfactory remedy currently exists. Our team developed a novel surgical approach called bilateral trigeminal/facial nerve combing (BTFC). This study aimed to evaluate the outcomes of patients who underwent BFTC (Clinical Trial Registry Number: ChiCTR2000033481). Method: We assigned 22 patients with MS to undergo BTFC. The primary outcome was assessed using the movement subscale of the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS-M) at 12 months postoperatively. The second outcome was evaluated using the Medical Outcome Study (MOS) 36-item Short Form Health Survey (SF-36), the dysfunction subscale of the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS-D), and the sub-item scores of the BFMDRS-M. Safety outcomes included the House-Brackmann (HB) functional grading score and the visual analog scale (VAS) for facial numbness. Results: At the final follow-up at 12 months, the BFMDRS-M showed a mean improvement of 70.7% from baseline. Mean scores of the BFMDRS-M sub-motor (including the eyes, mouth, and speech/swallowing) improved by 65.6, 81.00, and 60%, respectively. The median score of the total BFMDRS-D score was 0.70 ± 1.17 compared with 1.86 ± 2.21 at baseline. There were no serious operative complications in this population. The quality of life of the patients significantly improved (P < 0.05). Conclusion: BFTC has proven to be effective in relieving the symptoms of Meige syndrome. This novel surgical approach offers a new alternative treatment for patients who have failed to respond to medications, botulinum toxin injections, and deep brain stimulation (DBS). Clinical Trial Registration: https://www.chictr.org.cn/bin/project/edit?pid=54567, ChiCTR2000033481.

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