Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Más filtros




Base de datos
Asunto de la revista
Intervalo de año de publicación
1.
Comput Biol Med ; 178: 108783, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38909446

RESUMEN

Magnetic particle imaging (MPI) is an emerging non-invasive medical imaging tomography technology based on magnetic particles, with excellent imaging depth penetration, high sensitivity and contrast. Spatial resolution and signal-to-noise ratio (SNR) are key performance metrics for evaluating MPI, which are directly influenced by the gradient of the selection field (SF). Increasing the SF gradient can improve the spatial resolution of MPI, but will lead to a decrease in SNR. Deep learning (DL) methods may enable obtaining high-resolution images from low-resolution images to improve the MPI resolution under low gradient conditions. However, existing DL methods overlook the physical procedures contributing to the blurring of MPI images, resulting in low interpretability and hindering breakthroughs in resolution. To address this issue, we propose a dual-channel end-to-end network with prior knowledge embedding for MPI (DENPK-MPI) to effectively establish a latent mapping between low-gradient and high-gradient images, thus improving MPI resolution without compromising SNR. By seamlessly integrating MPI PSF with DL paradigm, DENPK-MPI leads to a significant improvement in spatial resolution performance. Simulation, phantom, and in vivo MPI experiments have collectively confirmed that our method can improve the resolution of low-gradient MPI images without sacrificing SNR, resulting in a decrease in full width at half maximum by 14.8%-23.8 %, and the accuracy of image reconstruction is 18.2 %-27.3 % higher than other DL methods. In conclusion, we propose a DL method that incorporates MPI prior knowledge, which can improve the spatial resolution of MPI without compromising SNR and possess improved biomedical application.

2.
ACS Nano ; 18(8): 6348-6358, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38314696

RESUMEN

The advancement in thin-film exfoliation for synthesizing oxide membranes has led to possibilities for creating artificially assembled heterostructures with structurally and chemically incompatible materials. The sacrificial layer method is a promising approach to exfoliate as-grown films from a compatible material system, allowing for their integration with dissimilar materials. Nonetheless, the conventional sacrificial layers often possess an intricate stoichiometry, thereby constraining their practicality and adaptability, particularly when considering techniques such as molecular beam epitaxy (MBE). This is where easy-to-grow binary alkaline-earth-metal oxides with a rock salt crystal structure are useful. These oxides, which include (Mg, Ca, Sr, Ba)O, can be used as a sacrificial layer covering a much broader range of lattice parameters compared to conventional sacrificial layers and are easily dissolvable in deionized water. In this study, we show the epitaxial growth of the single-crystalline perovskite SrTiO3 (STO) on sacrificial layers consisting of crystalline SrO, BaO, and Ba1-xCaxO films, employing a hybrid MBE method. Our results highlight the rapid (≤5 min) dissolution of the sacrificial layer when immersed in deionized water, facilitating the fabrication of millimeter-sized STO membranes. Using high-resolution X-ray diffraction, atomic-force microscopy, scanning transmission electron microscopy, impedance spectroscopy, and scattering-type near-field optical microscopy (SNOM), we demonstrate single-crystalline STO membranes with bulk-like intrinsic dielectric properties. The employment of alkaline earth metal oxides as sacrificial layers is likely to simplify membrane synthesis, particularly with MBE, thus expanding the research and application possibilities.

3.
Heliyon ; 9(12): e22634, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38125496

RESUMEN

Background: Ciprofol (HSK3486) is a novel gamma-aminobutyric acid type A (GABAA) receptor agonist that has attracted wide attention because of its lower injection pain and fewer adverse events. We summarized all available evidence and analyzed the efficacy and safety of ciprofol during procedural sedation and anesthesia induction. Methods: An electronic search of PubMed, Embase, Cochrane Library, Web of Science, Google Scholar, Science Direct, the Chinese National Knowledge Infrastructure, Wan Fang Data, and the VIP Chinese Journal Service platform was conducted from inception of databases to March 1, 2023. Risk ratio (RR) and mean difference (MD) with 95 % confidence interval (CI) were used separately for binary categorical and continuous variables. We performed trial sequential analysis and the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology to judge the certainty of evidence. Results: Fifteen randomized controlled trials with 2441 patients were included in this study. Ciprofol showed similar advantages to propofol in terms of induction success rate (RR = 1, 95 % CI = 0.99, 1.01, moderate certainty) and induction time (MD = 3.31, 95 % CI = -0.34, 6.95, low certainty), but did not increase the incidence of adverse events (RR = 0.88, 95 % CI = 0.78, 1.00, very low certainty), such as bradycardia (RR = 0.96, 95 % CI = 0.77, 1.21, high certainty), hypoxia (RR = 0.79, 95 % CI = 0.46, 1.37, p = 0.40, moderate certainty) and other adverse events. Although it may be associated with a longer time to be fully alert (MD = 1.22, 95 % CI = 0.32, 2.12, very low certainty), ciprofol significantly reduced injection pain (RR = 0.15, 95 % CI 0.09, 0.24, low certainty) and may have reduced the incidence of hypotension (RR = 0.77, 95 % CI = 0.63, 0.94, low certainty) and respiratory depression (RR = 0.29, 95 % CI = 0.15, 0.56, moderate certainty). Conclusion: Ciprofol and propofol had similar effects on most outcomes. While the time to full alertness may be prolonged, injection pain was significantly reduced, and hypotension and respiratory depression may be reduced compared with propofol. We believe that ciprofol is an effective alternative to intravenous anesthetic agents.

4.
PLoS One ; 18(11): e0294292, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37963140

RESUMEN

BACKGROUND: The use of dexmedetomidine rather than midazolam may improve ICU outcomes. We summarized the available recent evidence to further verify this conclusion. METHODS: An electronic search of PubMed, Medline, Embase, Cochrane Library, and Web of Science was conducted. Risk ratios (RR) were used for binary categorical variables, and for continuous variables, weighted mean differences (WMD) were calculated, the effect sizes are expressed as 95% confidence intervals (CI), and trial sequential analysis was performed. RESULTS: 16 randomized controlled trials were enrolled 2035 patients in the study. Dexmedetomidine as opposed to midazolam achieved a shorter length of stay in ICU (MD = -2.25, 95%CI = -2.94, -1.57, p<0.0001), lower risk of delirium (RR = 0.63, 95%CI = 0.50, 0.81, p = 0.0002), and shorter duration of mechanical ventilation (MD = -0.83, 95%CI = -1.24, -0.43, p<0.0001). The association between dexmedetomidine and bradycardia was also found to be significant (RR 2.21, 95%CI 1.31, 3.73, p = 0.003). We found no difference in hypotension (RR = 1.44, 95%CI = 0.87, 2.38, P = 0.16), mortality (RR = 1.02, 95%CI = 0.83, 1.25, P = 0.87), neither in terms of adverse effects requiring intervention, hospital length of stay, or sedation effects. CONCLUSIONS: Combined with recent evidence, compared with midazolam, dexmedetomidine decreased the risk of delirium, mechanical ventilation, length of stay in the ICU, as well as reduced patient costs. But dexmedetomidine could not reduce mortality and increased the risk of bradycardia.


Asunto(s)
Delirio , Dexmedetomidina , Humanos , Midazolam/efectos adversos , Dexmedetomidina/efectos adversos , Respiración Artificial , Bradicardia , Unidades de Cuidados Intensivos , Hipnóticos y Sedantes/efectos adversos
5.
ACS Nano ; 17(17): 16912-16922, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37638732

RESUMEN

The alkaline earth stannates are touted for their wide band gaps and the highest room-temperature electron mobilities among all of the perovskite oxides. CaSnO3 has the highest measured band gap in this family and is thus a particularly promising ultrawide band gap semiconductor. However, discouraging results from previous theoretical studies and failed doping attempts had described this material as "undopable". Here we redeem CaSnO3 using hybrid molecular beam epitaxy, which provides an adsorption-controlled growth for the phase-pure, epitaxial, and stoichiometric CaSnO3 films. By introducing lanthanum (La) as an n-type dopant, we demonstrate the robust and predictable doping of CaSnO3 with free electron concentrations, n3D, from 3.3 × 1019 cm-3 to 1.6 × 1020 cm-3. The films exhibit a maximum room-temperature mobility of 42 cm2 V-1 s-1 at n3D = 3.3 × 1019 cm-3. Despite having a comparable radius as the host ion, La expands the lattice parameter. Using density functional calculations, this effect is attributed to the energy gain by lowering the conduction band upon volume expansion. Finally, we exploit robust doping by fabricating CaSnO3-based field-effect transistors. The transistors show promise for CaSnO3's high-voltage capabilities by exhibiting low off-state leakage below 2 × 10-5 mA/mm at a drain-source voltage of 100 V and on-off ratios exceeding 106. This work serves as a starting point for future studies on the semiconducting properties of CaSnO3 and many devices that could benefit from CaSnO3's exceptionally wide band gap.

6.
Medicine (Baltimore) ; 101(41): e31184, 2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36253978

RESUMEN

OBJECTIVES: This meta-analysis aimed to assess the impact of nursing interventions (e.g., educational and empathic interviewing, motor exercise, therapeutic play interventions) on the perioperative outcome of children with congenital heart disease (CHD). METHODS: We searched PubMed, Embase, Web of Science, Scopus, Cochrane, EBSCO, The Chinese National Knowledge Infrastructure, Wan Fang Data and the VIP Chinese Journal Service platform from the date of database creation to August 2021. Our study adhered to the recommendations of the Cochrane Handbook and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. RevMan 5.4 and Stata 16.0 were used to complete the meta-analysis. RESULTS: This meta-analysis showed that comprehensive nursing intervention reduced both the length of hospital stay (weighted mean difference [WMD] = -1.982, 95%CI [-2.329, -1.634], P < .001) and the related risk of post-operative complications [OR = 0.345, 95%CI (0.225, 0.528), P < .001]. In addition, nursing intervention increased parental satisfaction with the care provided [OR = 0.308, 95%CI (1.923, 6.863), P < .001]. Nursing interventions have also had a positive impact in reducing preoperative anxiety [WMD = -6.721, 95% CI (-7.194, -6.249), P < .001] and postoperative pain [WMD = -7.103, 95% CI (-7.103, -7.663), P < .001] in children. CONCLUSIONS: This meta-analysis confirms the beneficial effects of comprehensive nursing interventions in terms of reduced complication rates and shorter hospital stays. The effectiveness of comprehensive nursing in reducing anxiety and pain levels was also demonstrated. The findings support the implementation of comprehensive care interventions in the perioperative period for children with CHD to improve clinical outcomes.


Asunto(s)
Cardiopatías Congénitas , Niño , Cardiopatías Congénitas/cirugía , Humanos , Tiempo de Internación , Padres , Complicaciones Posoperatorias
7.
Int J Nanomedicine ; 17: 2559-2575, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35698562

RESUMEN

Background: Tumor microenvironment (TME) plays a vital role in the development of hepatocellular carcinoma (HCC). Mounting evidence indicates that peripheral nerves could induce a shift from quiescent hepatic stellate cells (HSCs) to cancer-associated fibroblasts (CAFs) by secreting substance P (SP). The anti-tumor strategy by targeting "SP-HSCs-HCC" axis might be an effective therapy to inhibit tumor growth and metastasis. Objective: In this study, we prepared novel liposomes (CUR-APR/HA&GA-LPs) modified with hyaluronic acid (HA) and glycyrrhetinic acid (GA) for co-delivery aprepitant (APR) and curcumin (CUR), in which APR was chosen to inhibit the activation of HSCs by blocking SP/neurokinin-1 receptor (NK-1R), and CUR was used to induce apoptosis of tumor cells. Results: To mimic the TME, we established "SP+HSCs+HCC" co-cultured cell model in vitro. The results showed that CUR-APR/HA&GA-LPs could be taken up by CAFs and HCC simultaneously, and inhibit tumor cell migration. Meanwhile, the "SP+m-HSCs+HCC" co-implanted mice model was established to evaluate the anti-tumor effect in vivo. The results showed that CUR-APR/HA&GA-LPs could inhibit tumor proliferation and metastasis, and reduce extracellular matrix (ECM) deposition and tumor angiogenesis, indicating a superior anti-HCC effect. Conclusion: Overall, the combination therapy based on HA&GA-LPs could be a potential nano-sized formulation for anti-HCC therapy.


Asunto(s)
Carcinoma Hepatocelular , Curcumina , Ácido Glicirretínico , Neoplasias Hepáticas , Animales , Aprepitant , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Curcumina/farmacología , Ácido Hialurónico , Lipopolisacáridos , Liposomas , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Ratones , Microambiente Tumoral
8.
Sci Adv ; 6(41)2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33036980

RESUMEN

Microfluidic devices fabricated via soft lithography have demonstrated compelling applications such as lab-on-a-chip diagnostics, DNA microarrays, and cell-based assays. These technologies could be further developed by directly integrating microfluidics with electronic sensors and curvilinear substrates as well as improved automation for higher throughput. Current additive manufacturing methods, such as stereolithography and multi-jet printing, tend to contaminate substrates with uncured resins or supporting materials during printing. Here, we present a printing methodology based on precisely extruding viscoelastic inks into self-supporting microchannels and chambers without requiring sacrificial materials. We demonstrate that, in the submillimeter regime, the yield strength of the as-extruded silicone ink is sufficient to prevent creep within a certain angular range. Printing toolpaths are specifically designed to realize leakage-free connections between channels and chambers, T-shaped intersections, and overlapping channels. The self-supporting microfluidic structures enable the automatable fabrication of multifunctional devices, including multimaterial mixers, microfluidic-integrated sensors, automation components, and 3D microfluidics.

9.
Nanotechnology ; 31(40): 405203, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-32544901

RESUMEN

Black arsenic (BAs) is an elemental van der Waals semiconductor that is promising for a wide range of electronic and photonic applications. The narrow bandgap and symmetric band structure suggest that ambipolar (both n- and p-type) transport should be observable, however, only p-type transport has been experimentally studied to date. Here, we demonstrate and characterize ambipolar transport in exfoliated BAs field effect transistors. In the thickest flakes (∼ 80 nm), maximum currents, I max, up to 60 µA µm-1 and 90 µA µm-1are achieved for hole and electron conduction, respectively. Room-temperature hole (electron) mobilities up to 150 cm2 V-1 s-1 (175 cm2 V-1 s-1) were obtained, with temperature-dependence consistent with a phonon-scattering mechanism. The Schottky barrier height for Ni contacts to BAs was also extracted from the temperature-dependent measurements. I max for both n- and p-type conductivity was found to decrease with reduced thickness, while the ratio of I max to the minimum current, I min, increased. In the thinnest flakes (∼ 1.5 nm), only p-type conductivity was observed with the lowest value of I min = 400 fA µm-1. I max/I min ratios as high as 5 × 105 (5 × 102) were obtained, for p- (n-channel) devices. Finally, the ambipolarity was used to demonstrate a complementary logic inverter and a frequency doubling circuit.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA