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1.
Small ; : e2402482, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38855997

RESUMEN

Hydrogel as a solar evaporator shows great potential in freshwater production. However, hydrogels often lead to an imbalance between solar energy input and water supply management due to their excessively high saturated water content. Thus, achieving a stable water-energy-balance in hydrogel evaporators remains challenging. Here, by tortuosity engineering designed water transport channels, a seamless high-tortuosity/low-tortuosity/high-tortuosity structured hydrogel (SHLH structure hydrogel) evaporator is developed, which enables the hydrogel with customized water transport rate, leading to the controlled water supply at the evaporator interface. An excellent equilibrium between the photothermal conversion and water supply is established, and the maximum utilization of solar energy is realized, thereby achieving an excellent evaporation rate of 3.64 kg m-2 h-1 under one solar illumination. This tortuosity engineering controlled SHLH structured evaporator provides a novel strategy to attain water-energy-balance and expands new approaches for constructing hydrogel-based evaporators with tailored water transportation capacity.

2.
Nanotechnology ; 30(25): 255602, 2019 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-30802894

RESUMEN

Two-dimensional (2D) materials have attracted great interest due to their unique structures and exotic properties related to promising applications and fundamental research. Reducing the dimensionality of 2D materials into their 1D nanostructure is also highly desirable for the exploitation of novel properties and offers new research opportunities. In this work, we demonstrate a bottom-up synthesis of molybdenum disulfides (MoS2) nanoribbons on graphene substrate via chemical vapor deposition (CVD) by precisely tuning the growth parameters into a sulfur-enriched condition. MoS2 nanoribbons are mainly formed from the CVD grown MoS2 flakes along the armchair (AC) direction. Atomic resolution ADF-STEM imaging characterizations show an alternating presence of molybdenum and sulfur zigzag edge terminations at the edges of MoS2 nanoribbons. While at the apex of the nanoribbon, sulfur terminated zigzag edges become dominant. Taking these results together, we revealed the underlying growth mechanism of MoS2 nanoribbons. Electronic transport properties of the MoS2 nanoribbons were also measured by fabricating back-gate-effect transistors (FETs). The nanoribbon FETs present n-type behavior with a current on/off ratio higher than 104 at V DS = 1 and a carrier mobility of 1.39 cm2 V-1 s-1. This work offers a new route to synthesize 1D MoS2 nanoribbons, which has great potential in fabricating other 2D materials-derived 1D nanostructures.

3.
Adv Mater ; 36(18): e2309507, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38273713

RESUMEN

Maintaining a match between input solar energy and required energy by water supply management is key to achieving efficient interfacial solar-driven evaporation (ISDE). In practice, the solar radiation flux is constantly changing throughout the day, so keeping a dynamic water-energy-balance of ISDE is a big challenge. Herein, a photothermal water diode (WD) evaporator concept is proposed by an integrated hydrophilic/hydrophobic Janus absorber to overcome the issue. Due to the unique unidirectional water transport properties induced by asymmetric wettability, a self-adaptive balance between photothermal energy input and water uptake is established, thus realizing the energy matching and utilization maximization. The experimental and simulation results exhibit that with the increase of sunlight intensity, the water supply speed is significantly accelerated due to the dynamic management and self-regulation on water replenishment. Therefore, an excellent evaporation rate of up to 2.14 kg m-2 h-1 with a high efficiency of 93.7% under 1 sun illumination is achieved. This water diode engineering with Janus wettability provides a novel strategy and extends the path for designing solar evaporation systems with diverse water supply properties, which shows great potential in different environmental conditions.

4.
Cell Death Dis ; 15(2): 110, 2024 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-38310091

RESUMEN

Hepatocellular carcinoma (HCC) is an aggressive malignancy without effective therapeutic approaches. Here, we evaluate the tumor-intrinsic mechanisms that attenuate the efficacy of immune checkpoint inhibitor (ICI) that is observed in patients with advanced HCC who progress on first-line tyrosine kinase inhibitor (TKI) therapy. Upregulation of AXL observed in sorafenib- and lenvatinib-resistant HCCs is correlated with poor response towards TKI and ICI treatments. AXL upregulation protects sorafenib-resistant HCC cells from oxidative stress, mitochondrial damage, and accompanying immunogenic cell death through suppressed tumor necrosis factor-α (TNF-α) and STING-type I interferon pathways. Pharmacological inhibition of AXL abrogates the protective effect and re-sensitizes TKI-resistant HCC tumors to anti-PD-1 treatment. We suggest that targeting AXL in combination with anti-PD-1 may provide an alternative treatment scheme for HCC patients who progress on TKI treatment.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Sorafenib/farmacología , Sorafenib/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico
5.
ACS Nano ; 17(11): 10987-10995, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37256833

RESUMEN

Semiconducting carbon nanotube (CNT) film is a promising material for constructing high-performance complementary metal-oxide-semiconductor (CMOS) integrated circuits (ICs) and highly sensitive field-effect transistor (FET) bio/chemical sensors. Moreover, CNT logic transistors and sensors can be integrated through a compatible low-temperature fabrication process, providing enough thermal budget to construct monolithic three-dimensional (M3D) systems for smart sensors. However, an M3D sensing chip based on CNT film has not yet been demonstrated. In this work, we develop M3D technology to fabricate CNT CMOS ICs and CNT sensor arrays in two different layers; then, we demonstrate a preliminary M3D sensing system comprising CNT CMOS interfacing ICs in the bottom layer and CNT sensors in the upper layer through interlayer vias as links. As a typical example, a highly sensitive hydrogen sensing IC has been demonstrated to perform in situ sensing and processing functions through upper-layer FET-based hydrogen sensors exposed to the environment and bottom-layer CNT CMOS voltage-controlled oscillator (VCO) interfacing circuits. The M3D CNT sensing ICs convert hydrogen concentration information (8-128 ppm) to digital frequency information (0.78-1.11 GHz) with a sensitivity of 2.75 MHz/ppm. M3D sensing technology is expected to provide a universal sensing system for future smart sensing chips, including multitarget detection and ultralow power sensors.

6.
ACS Nano ; 17(22): 22240-22258, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-37966480

RESUMEN

Sorafenib, a first-line molecular-target drug for advanced hepatocellular carcinoma (HCC), has been shown to be a potent ferroptosis inducer in HCC. However, we found that there was a lower level of ferroptosis in sorafenib-resistant HCC samples than in sorafenib-sensitive HCC samples, suggesting that sorafenib resistance in HCC may be a result of ferroptosis suppression. Recent reports have shown that long noncoding RNAs (lncRNAs) are involved in programmed cell death (PCD), including apoptosis and ferroptosis. This study aimed to investigate the roles and underlying molecular mechanisms of lncRNAs in sorafenib-induced ferroptosis in HCC cells. Using lncRNA sequencing, we identified a ferroptosis-related lncRNA, URB1-antisense RNA 1 (AS1), which was highly expressed in sorafenib-resistant HCC samples and predicted poor survival in HCC. Furthermore, URB1-AS1 mitigates sorafenib-induced ferroptosis by inducing ferritin phase separation and reducing the cellular free iron content. Hypoxia inducible factor (HIF)-1α was identified as a key factor promoting URB1-AS1 expression in sorafenib-resistant HCC cells. Notably, we found that specifically inhibiting the expression of URB1-AS1 with N-acetylgalactosamine (GalNAc)-small interfering (si)URB1-AS1 successfully enhanced the sensitivity of HCC cells to sorafenib in an in vivo tumor model. Our study uncovered a critical role for URB1-AS1 in the repression of ferroptosis, suggesting URB1-AS1 targeting may represent a potential approach to overcome sorafenib resistance in HCC.


Asunto(s)
Carcinoma Hepatocelular , Ferroptosis , Neoplasias Hepáticas , MicroARNs , ARN Largo no Codificante , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Sorafenib/farmacología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , ARN sin Sentido , Ferritinas/metabolismo , MicroARNs/genética , Línea Celular Tumoral , ARN Interferente Pequeño/genética , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Proteínas Nucleares/genética
7.
Cancers (Basel) ; 14(21)2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36358763

RESUMEN

An increasing body of evidence suggests that cancer stem cells (CSCs) utilize reprogrammed metabolic strategies to adapt to a hostile tumor microenvironment (TME) for survival and stemness maintenance. Such a metabolic alteration in CSCs is facilitated by microenvironmental cues including metabolites such as glucose, amino acids and lipids, and environmental properties such as hypoxic and acidic TME. Similarly, metabolites uptake from the diet exerts critical imprints to the metabolism profile of CSCs and directly influence the maintenance of the CSC population. Moreover, CSCs interact with tumor-infiltrating cells inside the CSC niche to promote cancer stemness, ultimately contributing to tumor development and progression. Understanding the underlying mechanisms of how CSCs employ metabolic plasticity in response to different microenvironmental cues represents a therapeutic opportunity for better cancer treatment.

8.
Front Neurorobot ; 15: 648855, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34335219

RESUMEN

Background: Surface electromyography (sEMG) based robot-assisted rehabilitation systems have been adopted for chronic stroke survivors to regain upper limb motor function. However, the evaluation of rehabilitation effects during robot-assisted intervention relies on traditional manual assessments. This study aimed to develop a novel sEMG data-driven model for automated assessment. Method: A data-driven model based on a three-layer backpropagation neural network (BPNN) was constructed to map sEMG data to two widely used clinical scales, i.e., the Fugl-Meyer Assessment (FMA) and the Modified Ashworth Scale (MAS). Twenty-nine stroke participants were recruited in a 20-session sEMG-driven robot-assisted upper limb rehabilitation, which consisted of hand reaching and withdrawing tasks. The sEMG signals from four muscles in the paretic upper limbs, i.e., biceps brachii (BIC), triceps brachii (TRI), flexor digitorum (FD), and extensor digitorum (ED), were recorded before and after the intervention. Meanwhile, the corresponding clinical scales of FMA and MAS were measured manually by a blinded assessor. The sEMG features including Mean Absolute Value (MAV), Zero Crossing (ZC), Slope Sign Change (SSC), Root Mean Square (RMS), and Wavelength (WL) were adopted as the inputs to the data-driven model. The mapped clinical scores from the data-driven model were compared with the manual scores by Pearson correlation. Results: The BPNN, with 15 nodes in the hidden layer and sEMG features, i.e., MAV, ZC, SSC, and RMS, as the inputs to the model, was established to achieve the best mapping performance with significant correlations (r > 0.9, P < 0.001), according to the FMA. Significant correlations were also obtained between the mapped and manual FMA subscores, i.e., FMA-wrist/hand and FMA-shoulder/elbow, before and after the intervention (r > 0.9, P < 0.001). Significant correlations (P < 0.001) between the mapped and manual scores of MASs were achieved, with the correlation coefficients r = 0.91 at the fingers, 0.88 at the wrist, and 0.91 at the elbow after the intervention. Conclusion: An sEMG data-driven BPNN model was successfully developed. It could evaluate upper limb motor functions in chronic stroke and have potential application in automated assessment in post-stroke rehabilitation, once validated with large sample sizes. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02117089.

9.
Cell Rep ; 36(8): 109617, 2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34433044

RESUMEN

The liver plays central roles in coordinating different metabolic processes, such as the catabolism of amino acids. In this study, we identify a loss of tyrosine catabolism and a concomitant increase in serum tyrosine levels during liver cancer development. Liver cells with disordered tyrosine catabolism, as exemplified by the suppression of a tyrosine catabolic enzyme 4-hydroxyphenylpyruvate dioxygenase (HPD), display augmented tumorigenic and proliferative potentials. Metabolomics profiling and isotope tracing reveal the metabolic reliance of HPD-silenced cells on glutamine, coupled with increased tricarboxylic acid cycle metabolites and their associated amino acid pools. Mechanistically, HPD silencing reduces ketone bodies, which regulate the proliferative and metabolic phenotypes via the AMPK/mTOR/p70S6 kinase pathway and mTOR-dependent glutaminase (GLS) activation. Collectively, our results demonstrate a metabolic link between tyrosine and glutamine metabolism, which could be exploited as a potentially promising anticancer therapy for liver cancer.


Asunto(s)
4-Hidroxifenilpiruvato Dioxigenasa/antagonistas & inhibidores , Glutamina/metabolismo , Neoplasias Hepáticas/metabolismo , Serina-Treonina Quinasas TOR/efectos de los fármacos , Tirosina/metabolismo , Animales , Línea Celular Tumoral , Humanos , Hígado/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Ratones Endogámicos BALB C , Serina-Treonina Quinasas TOR/metabolismo
10.
Front Neurol ; 8: 679, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29312116

RESUMEN

BACKGROUND: Impaired hand dexterity is a major disability of the upper limb after stroke. An electromyography (EMG)-driven neuromuscular electrical stimulation (NMES) robotic hand was designed previously, whereas its rehabilitation effects were not investigated. OBJECTIVES: This study aims to investigate the rehabilitation effectiveness of the EMG-driven NMES-robotic hand-assisted upper-limb training on persons with chronic stroke. METHOD: A clinical trial with single-group design was conducted on chronic stroke participants (n = 15) who received 20 sessions of EMG-driven NMES-robotic hand-assisted upper-limb training. The training effects were evaluated by pretraining, posttraining, and 3-month follow-up assessments with the clinical scores of the Fugl-Meyer Assessment (FMA), the Action Research Arm Test (ARAT), the Wolf Motor Function Test, the Motor Functional Independence Measure, and the Modified Ashworth Scale (MAS). Improvements in the muscle coordination across the sessions were investigated by EMG parameters, including EMG activation level and Co-contraction Indexes (CIs) of the target muscles in the upper limb. RESULTS: Significant improvements in the FMA shoulder/elbow and wrist/hand scores (P < 0.05), the ARAT (P < 0.05), and in the MAS (P < 0.05) were observed after the training and sustained 3 months later. The EMG parameters indicated a significant decrease of the muscle activation level in flexor digitorum (FD) and biceps brachii (P < 0.05), as well as a significant reduction of CIs in the muscle pairs of FD and triceps brachii and biceps brachii and triceps brachii (P < 0.05). CONCLUSION: The upper-limb training integrated with the assistance from the EMG-driven NMES-robotic hand is effective for the improvements of the voluntary motor functions and the muscle coordination in the proximal and distal joints. Furthermore, the motor improvement after the training could be maintained till 3 months later. TRIAL REGISTRATION: ClinicalTrials.gov. NCT02117089; date of registration: April 10, 2014.

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