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1.
Nat Commun ; 15(1): 2098, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38459034

RESUMEN

Yutu-2 rover conducted an exciting expedition on the 41st lunar day to investigate a fin-shaped rock at Longji site (45.44°S, 177.56°E) by extending its locomotion margin on perilous peaks. The varied locomotion encountered, especially multi-form wheel slippage, during the journey to the target rock, established unique conditions for a fin-grained lunar regolith analysis regarding bearing, shear and lateral properties based on terramechanics. Here, we show a tri-aspect characterization of lunar regolith and infer the rock's origin using a digital twin. We estimate internal friction angle within 21.5°-42.0° and associated cohesion of 520-3154 Pa in the Chang'E-4 operational site. These findings suggest shear characteristics similar to Apollo 12 mission samples but notably higher cohesion compared to regolith investigated on most nearside lunar missions. We estimate external friction angle in lateral properties to be within 8.3°-16.5°, which fills the gaps of the lateral property estimation of the lunar farside regolith and serves as a foundational parameter for subsequent engineering verifications. Our in-situ spectral investigations of the target rock unveil its composition of iron/magnesium-rich low-calcium pyroxene, linking it to the Zhinyu crater (45.34°S, 176.15°E) ejecta. Our results indicate that the combination of in-situ measurements with robotics technology in planetary exploration reveal the possibility of additional source regions contributing to the local materials at the Chang'E-4 site, implying a more complicated geological history in the vicinity.

2.
Curr Probl Cardiol ; 49(2): 102215, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38013012

RESUMEN

BACKGROUND: While previous studies have established a significant correlation between baseline remnant cholesterol (RC) and ischemic heart disease (IHD), the enduring impact of RC on incident IHD remains to be elucidated. This study aimed to investigate the association between cumulative remnant cholesterol(cumRC) and IHD susceptibility. METHODS: Participating from the Kailuan Study (2006-2010) were enrolled, excluding those with prior myocardial infarction, coronary artery revascularization and cancer across three consecutive examinations. The cumRC derived by multiplying the average RC with the interval between the two consecutive assessments. Participants were segmented into quartiles based on cumRC levels: Q1 (cumRC < 2.69 mmol/l); Q2 (2.69 ≤ cumRC < 4.04 mmol/l); Q3(4.04 ≤ cumRC < 5.65 mmol/l) and Q4 (cumRC ≥ 5.65 mmol/l). The correlation between cumRC and IHD risk was ascertained by using multivariable Cox proportional hazard models. RESULT: The analysis encompassed 42,639 participants. Over an average tracking period of 9.97 years, 1,205 instances of IHD were identified. IHD susceptibility augmented with rising cumRC quartiles. After adjusting for potential confounders, the hazard ratios for IHD events were 1.06 (0.88-1.29) for Q2, 1.30 (1.08-1.56) for Q3 and 1.69 (1.42-2.01) for Q4, relative to Q1. Elevated cumRC was significantly associated with a heightened IHD risk, a trend consistent in both subgroup and sensitivity analyses. CONCLUSION: Elevated cumRC significantly correlates with a higher risk of IHD, suggesting that consistent monitoring and regulation of RC might be instrumental in IHD prevention.


Asunto(s)
Isquemia Miocárdica , Humanos , Estudios Prospectivos , Triglicéridos , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/etiología , Colesterol , Factores de Riesgo
3.
Curr Probl Cardiol ; 49(1 Pt C): 102173, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37913930

RESUMEN

OBJECTIVE: This study aims to explore the ramifications of weight fluctuations preceding and succeeding the identification of heart failure (HF) on all-cause mortality. METHODS: The research cohort comprised individuals engaged in the Kailuan Group's health assessments from 2006 to 2018, who were subsequently diagnosed with HF. The moment of HF recognition marked the commencement of the monitoring period, culminating either at the instance of comprehensive mortality or at the conclusion of the monitoring phase (December 31, 2021). RESULTS: Throughout an average monitoring span of 5.8±3.5 years, from the 3115 qualified participants, 957 instances (30.7%) encountered comprehensive mortality. The COX proportional hazards regression model's outcomes revealed that, post the adjustment for potential confounders, in comparison to the Q3 category, the Q1 category had the highest hazard ratios (95% confidence intervals) of 1.71 (1.43-2.05). CONCLUSION: Weight reduction before and post the HF diagnosis stands as an autonomous risk determinant for comprehensive mortality.


Asunto(s)
Insuficiencia Cardíaca , Humanos , Factores de Riesgo , Modelos de Riesgos Proporcionales , Insuficiencia Cardíaca/diagnóstico
4.
Sensors (Basel) ; 23(24)2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38139601

RESUMEN

Identifying terrain parameters is important for high-fidelity simulation and high-performance control of planetary rovers. The wheel-terrain interaction classes (WTICs) are usually different for rovers traversing various types of terrain. Every terramechanics model corresponds to its wheel-terrain interaction class (WTIC). Therefore, for terrain parameter identification of the terramechanics model when rovers traverse various terrains, terramechanics model switching corresponding to the WTIC needs to be solved. This paper proposes a speed-independent vibration-based method for WTIC recognition to switch the terramechanics model and then identify its terrain parameters. In order to switch terramechanics models, wheel-terrain interactions are divided into three classes. Three vibration models of wheels under three WTICs have been built and analyzed. Vibration features in the models are extracted and non-dimensionalized to be independent of wheel speed. A vibration-feature-based recognition method of the WTIC is proposed. Then, the terrain parameters of the terramechanics model corresponding to the recognized WTIC are identified. Experiment results obtained using a Planetary Rover Prototype show that the identification method of terrain parameters is effective for rovers traversing various terrains. The relative errors of estimated wheel-terrain interaction force with identified terrain parameters are less than 16%, 12%, and 9% for rovers traversing hard, gravel, and sandy terrain, respectively.

5.
ACS Photonics ; 10(9): 3008-3019, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37743940

RESUMEN

Multiphoton lithography inside a mesoporous host can create optical components with continuously tunable refractive indices in three-dimensional (3D) space. However, the process is very sensitive at exposure doses near the photoresist threshold, leading previous work to reliably achieve only a fraction of the available refractive index range for a given material system. Here, we present a method for greatly enhancing the uniformity of the subsurface micro-optics, increasing the reliable index range from 0.12 (in prior work) to 0.37 and decreasing the standard deviation (SD) at threshold from 0.13 to 0.0021. Three modifications to the previous method enable higher uniformity in all three spatial dimensions: (1) calibrating the planar write field of mirror galvanometers using a spatially varying optical transmission function which corrects for large-scale optical aberrations; (2) periodically relocating the piezoelectrically driven stage, termed piezo-galvo dithering, to reduce small-scale errors in writing; and (3) enforcing a constant time between each lateral cross section to reduce variation across all writing depths. With this new method, accurate fabrication of optics of any index between n = 1.20 and 1.57 (SD < 0.012 across the full range) was achieved inside a volume of porous silica. We demonstrate the importance of this increased accuracy and precision by fabricating and characterizing calibrated two-dimensional (2D) line gratings and flat gradient index lenses with significantly better performance than the corresponding control devices. As a visual representation, the University of Illinois logo made with 2D line gratings shows significant improvement in its color uniformity across its width.

6.
Artículo en Inglés | MEDLINE | ID: mdl-37399155

RESUMEN

Based on actor-critic neural networks (NNs), an optimal controller is proposed for solving the constrained control problem of an affine nonlinear discrete-time system with disturbances. The actor NNs provide the control signals and the critic NNs work as the performance indicators of the controller. By converting the original state constraints into new input constraints and state constraints, the penalty functions are introduced into the cost function, and then the constrained optimal control problem is transformed into an unconstrained one. Further, the relationship between the optimal control input and worst-case disturbance is obtained using the Game theory. With Lyapunov stability theory, the control signals are ensured to be uniformly ultimately bounded (UUB). Finally, the effectiveness of the control algorithms is tested through a numeral simulation using a third-order dynamic system.

7.
Mar Drugs ; 21(5)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37233490

RESUMEN

Pseudomonas aeruginosa is an opportunistic pathogen that infects patients by regulating virulence factors and biofilms through a quorum sensing (QS) system to protect itself from antibiotics and environmental stress. Therefore, the development of quorum sensing inhibitors (QSIs) is expected to become a new strategy for studying drug resistance to P. aeruginosa infections. Marine fungi are valuable resources for screening QSIs. A marine fungus, Penicillium sp. JH1, with anti-QS activity was isolated from the offshore waters of Qingdao (China), and citrinin, a novel QSI, was purified from secondary metabolites of this fungus. Citrinin could significantly inhibit the production of violacein in Chromobacterium violaceum CV12472 and the production of three virulence factors (elastase, rhamnolipid and pyocyanin) in P. aeruginosa PAO1. It could also inhibit the biofilm formation and motility of PAO1. In addition, citrinin downregulated the transcript levels of nine genes (lasI, rhlI, pqsA, lasR, rhlR, pqsR, lasB, rhlA and phzH) associated with QS. Molecular docking results showed that citrinin bound to PqsR and LasR with better affinity than the natural ligands. This study laid a foundation for the further study of the structure optimization and structure-activity relationship of citrinin.


Asunto(s)
Citrinina , Percepción de Quorum , Humanos , Pseudomonas aeruginosa/fisiología , Citrinina/farmacología , Simulación del Acoplamiento Molecular , Biopelículas , Factores de Virulencia/metabolismo , Antibacterianos/química , Proteínas Bacterianas/metabolismo
8.
Nat Commun ; 14(1): 3119, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37253761

RESUMEN

Compact visible wavelength achromats are essential for miniaturized and lightweight optics. However, fabrication of such achromats has proved to be exceptionally challenging. Here, using subsurface 3D printing inside mesoporous hosts we densely integrate aligned refractive and diffractive elements, forming thin high performance hybrid achromatic imaging micro-optics. Focusing efficiencies of 51-70% are achieved for 15µm thick, 90µm diameter, 0.3 numerical aperture microlenses. Chromatic focal length errors of less than 3% allow these microlenses to form high-quality images under broadband illumination (400-700 nm). Numerical apertures upwards of 0.47 are also achieved at the cost of some focusing efficiency, demonstrating the flexibility of this approach. Furthermore, larger area images are reconstructed from an array of hybrid achromatic microlenses, laying the groundwork for achromatic light-field imagers and displays. The presented approach precisely combines optical components within 3D space to achieve thin lens systems with high focusing efficiencies, high numerical apertures, and low chromatic focusing errors, providing a pathway towards achromatic micro-optical systems.

9.
Natl Sci Rev ; 10(5): nwad045, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37056443

RESUMEN

Physical characteristics of terrains, such as softness and friction, provide essential information for legged robots to avoid non-geometric obstacles, like mires and slippery stones, in the wild. The perception of such characteristics often relies on tactile perception and vision prediction. Although tactile perception is more accurate, it is limited to close-range use; by contrast, establishing a supervised or self-supervised contactless prediction system using computer vision requires adequate labeled data and lacks the ability to adapt to the dynamic environment. In this paper, we simulate the behavior of animals and propose an unsupervised learning framework for legged robots to learn the physical characteristics of terrains, which is the first report to manage it online, incrementally and with the ability to solve cognitive conflicts. The proposed scheme allows robots to interact with the environment and adjust their cognition in real time, therefore endowing robots with the adaptation ability. Indoor and outdoor experiments on a hexapod robot are carried out to show that the robot can extract tactile and visual features of terrains to create cognitive networks independently; an associative layer between visual and tactile features is created during the robot's exploration; with the layer, the robot can autonomously generate a physical segmentation model of terrains and solve cognitive conflicts in an ever-changing environment, facilitating its safe navigation.

10.
Small Methods ; 7(3): e2201342, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36683180

RESUMEN

The piezoelectric properties of semiconductor micro/nanowires (M/NWs) are crucial for optimizing semiconductors' electronic structure and carrier dynamics. However, the dynamic characterization of the piezoelectric properties of M/NWs remains challenging. Here, a Kelvin probe force microscopy technique based on a dual-probe atomic force microscope is developed to achieve in situ piezoelectric potential measurements of dynamic bending MWs. This technique can not only characterize the surface potential on different crystal faces of ZnO MWs in a natural state through controllable axial rotation, but also investigate the piezoelectric potential of the dynamically bending flake-like ZnO MW at different points and under different strain loads. The results show that the surface potentials of different faces/positions of the ZnO MWs are varied significantly, and determine that the quasi-static conditions piezo-strain factor of the flake-like ZnO MW is 0.28 V/%, while the factor was 0.14 V/% under low-frequency (⩽5 Hz) sinusoidal strain loading. This work provides a significant methodology to further study piezoelectric materials, and it aims to facilitate their applications in piezoelectric devices and systems.

11.
Entropy (Basel) ; 24(9)2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36141190

RESUMEN

It is important for Mars exploration rovers to achieve autonomous and safe mobility over rough terrain. Terrain classification can help rovers to select a safe terrain to traverse and avoid sinking and/or damaging the vehicle. Mars terrains are often classified using visual methods. However, the accuracy of terrain classification has been less than 90% in read operations. A high-accuracy vision-based method for Mars terrain classification is presented in this paper. By analyzing Mars terrain characteristics, novel image features, including multiscale gray gradient-grade features, multiscale edges strength-grade features, multiscale frequency-domain mean amplitude features, multiscale spectrum symmetry features, and multiscale spectrum amplitude-moment features, are proposed that are specifically targeted for terrain classification. Three classifiers, K-nearest neighbor (KNN), support vector machine (SVM), and random forests (RF), are adopted to classify the terrain using the proposed features. The Mars image dataset MSLNet that was collected by the Mars Science Laboratory (MSL, Curiosity) rover is used to conduct terrain classification experiments. The resolution of Mars images in the dataset is 256 × 256. Experimental results indicate that the RF classifies Mars terrain at the highest level of accuracy of 94.66%.

12.
Cancer Cell Int ; 22(1): 291, 2022 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-36153574

RESUMEN

BACKGROUND: Perinatal blood including umbilical cord blood and placental blood are splendid sources for allogeneic NK cell generation with high cytotoxicity of combating pathogenic microorganism and malignant tumor. Despite the generation of NK cells from the aforementioned perinatal blood, yet the systematical and detailed information of the biological and transcriptomic signatures of UC-NKs and P-NKs before large-scale clinical applications in disease remodeling is still largely obscure. METHODS: Herein, we took advantage of the "3IL"-based strategy for high-efficient generation of NK cells from umbilical cord blood and placental blood (UC-NKs and P-NKs), respectively. On the one hand, we conducted flow cytometry (FCM) assay and coculture to evaluate the subpopulations, cellular vitality and cytotoxic activity of the aforementioned NK cells. On the other hand, with the aid of RNA-SEQ and multiple bioinformatics analyses, we further dissected the potential diversities of UC-NKs and P-NKs from the perspectives of transcriptomes. RESULTS: On the basis of the "3IL" strategy, high-efficient NKs were generated from mononuclear cells (MNCs) in perinatal blood. P-NKs revealed comparable ex vivo expansion but preferable activation and cytotoxicity upon K562 cells over UC-NKs. Both of the two NKs showed diversity in cellular vitality and transcriptome including apoptotic cells, cell cycle, gene expression profiling and the accompanied multifaceted biological processes. CONCLUSIONS: Our data revealed the multifaceted similarities and differences of UC-NKs and P-NKs both at the cellular and molecular levels. Our findings supply new references for allogeneic NK cell-based immunotherapy in regenerative medicine and will benefit the further exploration for illuminating the underlying mechanism as well.

13.
ACS Appl Mater Interfaces ; 14(28): 32719-32728, 2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35816692

RESUMEN

Traditional Kelvin probe force microscopy (KPFM) is mainly limited to the characterization of two-dimensional (2D) surfaces, and in situ surface potential (SP) imaging along 3D device surfaces remains a challenge. This paper presents a multimode 3D-KPFM based on an orthogonal cantilever probe (OCP) that can achieve SP mapping of 3D micronano structures. It integrates three working modes: a bending mode for 2D horizontal surface imaging, a torsion mode for vertical sidewall imaging, and a vector tracking-based 3D scanning mode. The customized OCP has a nanoscale tip protruding from the side and underside of the cantilever, rather than the front, and the extended tip makes the proposed approach universally applicable for 3D detection from the nanometer to micrometer scale. The spatial resolution of the proposed method is analyzed by simulation, which shows it can reduce the cantilever homogenization effect. Linearity and energy resolution measurements show that the proposed method has comparable performance to traditional methods. A comparative experiment using a gold-silicon interface verifies the accuracy of the reported method in its bending and torsion modes. Further, the imaging ability of the 3D scanning mode is confirmed in the 3D characterization of a step grating. This technique is applied to the in situ characterization of a microforce sensor with microcomb structures. The experiment results show that this method can excellently achieve the 3D quantitative characterization of topography and SP, including critical dimensions and SP along a 3D device surface. This novel 3D-KPFM technique has many potential applications in the further exploration of 3D micronano devices.

14.
IEEE Trans Cybern ; 52(2): 1138-1149, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32396119

RESUMEN

This article proposes an adaptive finite-time tracking control based on fuzzy-logic systems (FLSs) for an uncertain nonstrict nonlinear multi-input-multi-output (MIMO) full-state-constrained system with the coupled uncertain dead-zone input. By using three kinds of FLSs: the uncertain system, the uncertain dead zone, and the uncertain input transfer inverse matrix are approximated using the system function FLS, dead-zone FLS, and input transfer inverse matrix FLS, respectively. After defining the barrier Lyapunov function, the fuzzy-based adaptive tracking controllers are designed, and the fuzzy weights are updated through the proposed adaptive laws. Then, based on the extended finite-time convergence theorem, with the design parameters chosen properly, the target uncertain nonlinear system is guaranteed to be semiglobal practical finite-time stable (SGPFS); and the full-state constraints are not violated while avoiding the effects of the dead zones. Furthermore, a simulation is presented to verify the validity of the proposed algorithm.

15.
Mol Med Rep ; 24(1)2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34080663

RESUMEN

Sepsis­induced myocardial dysfunction is one of the features of multiple organ dysfunction in sepsis, which is associated with extremely high mortality and is characterized by impaired myocardial compliance. To date, there are few effective treatment options available to cure sepsis. Tannic acid (TA) is reportedly protective during sepsis; however, the underlying mechanisms by which TA protects against septic heart injury remain elusive. The present study investigated the potential effects and underlying mechanisms of TA in alleviating lipopolysaccharide (LPS)­induced H9C2 cardiomyocyte cell apoptosis. H9C2 cells were treated with LPS (15 µg/ml), TA (10 µM) and TA + LPS; control cells were treated with medium only. Apoptosis was measured using flow cytometry, reverse transcription­quantitative PCR (RT­qPCR) and western blot analysis. Additionally, the levels of cellular reactive oxygen species (ROS), malondialdehyde and nicotinamide adenine dinucleotide phosphate were evaluated. Western blotting and RT­qPCR were also employed to detect the expression levels of endoplasmic reticulum (ER) stress­associated functional proteins. The present findings demonstrated that TA reduced the degree of LPS­induced H9C2 cell injury, including inhibition of ROS production and ER stress (ERS)­associated apoptosis. ERS­associated functional proteins, including activating transcription factor 6, protein kinase­like ER kinase, inositol­requiring enzyme 1, spliced X box­binding protein 1 and C/EBP­homologous protein were suppressed in response to TA treatment. Furthermore, the expression levels of ERS­associated apoptotic proteins, including c­Jun N­terminal kinase, Bax, cytochrome c, caspase­3, caspase­12 and caspase­9 were reduced following treatment with TA. Additionally, the protective effects of TA on LPS­induced H9C2 cells were partially inhibited following treatment with the ROS inhibitor N­acetylcysteine, which demonstrated that ROS mediated ERS­associated apoptosis and TA was able to decrease ROS­mediated ERS­associated apoptosis. Collectively, the present findings demonstrated that the protective effects of TA against LPS­induced H9C2 cell apoptosis may be associated with the amelioration of ROS­mediated ERS. These findings may assist the development of potential novel therapeutic methods to inhibit the progression of myocardial cell injury.


Asunto(s)
Apoptosis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Lipopolisacáridos/efectos adversos , Especies Reactivas de Oxígeno/metabolismo , Taninos/farmacología , Acetilcisteína/farmacología , Animales , Línea Celular , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Ratas
16.
IEEE Trans Cybern ; 51(1): 382-392, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31567108

RESUMEN

Considering the uncertain nonstrict nonlinear system with dead-zone input, an adaptive neural network (NN)-based finite-time online optimal tracking control algorithm is proposed. By using the tracking errors and the Lipschitz linearized desired tracking function as the new state vector, an extended system is present. Then, a novel Hamilton-Jacobi-Bellman (HJB) function is defined to associate with the nonquadratic performance function. Further, the upper limit of integration is selected as the finite-time convergence time, in which the dead-zone input is considered. In addition, the Bellman error function can be obtained from the Hamiltonian function. Then, the adaptations of the critic and action NN are updated by using the gradient descent method on the Bellman error function. The semiglobal practical finite-time stability (SGPFS) is guaranteed, and the tracking errors convergence to a compact set by zero in a finite time.

17.
Entropy (Basel) ; 22(7)2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-33286542

RESUMEN

It is necessary to switch the control strategies for propulsion system frequently according to the changes of sea states in order to ensure the stability and safety of the navigation. Therefore, identifying the current sea state timely and effectively is of great significance to ensure ship safety. To this end, a reasoning model that is based on maximum likelihood evidential reasoning (MAKER) rule is developed to identify the propeller ventilation type, and the result is used as the basis for the sea states identification. Firstly, a data-driven MAKER model is constructed, which fully considers the interdependence between the input features. Secondly, the genetic algorithm (GA) is used to optimize the parameters of the MAKER model in order to improve the evaluation accuracy. Finally, a simulation is built to obtain experimental data to train the MAKER model, and the validity of the model is verified. The results show that the intelligent sea state identification model that is based on the MAKER rule can identify the propeller ventilation type more accurately, and finally realize intelligent identification of sea states.

18.
Light Sci Appl ; 9(1): 196, 2020 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-33298832

RESUMEN

Direct laser writing (DLW) has been shown to render 3D polymeric optical components, including lenses, beam expanders, and mirrors, with submicrometer precision. However, these printed structures are limited to the refractive index and dispersive properties of the photopolymer. Here, we present the subsurface controllable refractive index via beam exposure (SCRIBE) method, a lithographic approach that enables the tuning of the refractive index over a range of greater than 0.3 by performing DLW inside photoresist-filled nanoporous silicon and silica scaffolds. Adjusting the laser exposure during printing enables 3D submicron control of the polymer infilling and thus the refractive index and chromatic dispersion. Combining SCRIBE's unprecedented index range and 3D writing accuracy has realized the world's smallest (15 µm diameter) spherical Luneburg lens operating at visible wavelengths. SCRIBE's ability to tune the chromatic dispersion alongside the refractive index was leveraged to render achromatic doublets in a single printing step, eliminating the need for multiple photoresins and writing sequences. SCRIBE also has the potential to form multicomponent optics by cascading optical elements within a scaffold. As a demonstration, stacked focusing structures that generate photonic nanojets were fabricated inside porous silicon. Finally, an all-pass ring resonator was coupled to a subsurface 3D waveguide. The measured quality factor of 4600 at 1550 nm suggests the possibility of compact photonic systems with optical interconnects that traverse multiple planes. SCRIBE is uniquely suited for constructing such photonic integrated circuits due to its ability to integrate multiple optical components, including lenses and waveguides, without additional printed supports.

19.
Cell Biosci ; 10: 72, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32489586

RESUMEN

BACKGROUND: Arginine vasopressin (AVP) is elevated in patients with heart failure, and the increase in the AVP concentration in plasma is positively correlated with disease severity and mortality. Metoprolol (Met) is a beta blocker that is widely used in the clinic to treat pathological cardiac hypertrophy and to improve heart function. However, the specific mechanism by which Met alleviates AVP-induced pathological cardiac hypertrophy is still unknown. Our current study aimed to evaluate the inhibitory effects of Met on AVP-induced cardiomyocyte hypertrophy and the underlying mechanisms. METHODS: AVP alone or AVP plus Met was added to the wild type or AKT1-overexpressing rat cardiac H9C2 cell line. The cell surface areas and ANP/BNP/ß-MHC expressions were used to evaluate the levels of hypertrophy. Western bolting was used to analyze AKT1/P-AKT1, AKT2/P-AKT2, total AKT, SERCA2, and Phospholamban (PLN) expression. Fluo3-AM was used to measure the intracellular Ca2+ stores. RESULTS: In the current study, we found that AKT1 but not AKT2 mediated the pathogenesis of AVP-induced cardiomyocyte hypertrophy. Sustained stimulation (48 h) with AVP led to hypertrophy in the H9C2 rat cardiomyocytes, resulting in the downregulation of AKT1 (0.48 fold compared to control) and SERCA2 (0.62 fold), the upregulation of PLN (1.32 fold), and the increase in the cytoplasmic calcium concentration (1.52 fold). In addition, AKT1 overexpression increased the expression of SERCA2 (1.34 fold) and decreased the expression of PLN (0.48 fold) in the H9C2 cells. Moreover, we found that Met could attenuate the AVP-induced changes in AKT1, SERCA2 and PLN expression and decreased the cytoplasmic calcium concentration in the H9C2 cells. CONCLUSIONS: Our results demonstrated that the AKT1-SERCA2 cascade served as an important regulatory pathway in AVP-induced pathological cardiac hypertrophy.

20.
Biochem Cell Biol ; 98(6): 669-675, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32502356

RESUMEN

The study investigated the expression of long noncoding RNA (lncRNA) MALAT1 in high glucose (HG)-induced human vascular endothelial cells (HUVECs) and the role of MALAT1 in the apoptosis of HG-induced HUVECs. The HUVECs were cultured and induced with 25 mmol/L HG. After that, the HUVECs were transfected with MALAT1 siRNA. The expression levels of MALAT1 were detected with qPCR, whereas the expression levels of Bax, Bcl-2, cleaved-caspase-3, cleaved-caspase-9, p-65, and p-p65 were detected using Western blot. The roles of MALAT1 in cell activities, including apoptosis, were evaluated using the CCK-8 assay, TUNEL staining, and flow cytometry. The expression levels of inflammatory factors (TNF-α and IL-6) were measured using ELISA. The expression levels of MALAT1, TNF-α, and IL-6 in HUVECs were increased in the HG environment; however, when MALAT1 was silenced in the HUVECs, cell proliferation increased significantly, the expression levels of TNF-α, IL-6, Bax, cleaved-caspase-3, and cleaved-caspase-9 decreased, and the rate of apoptosis also decreased. Silencing MALAT1 inhibited the expression of p-p65 in HG-induced HUVECs. In conclusion, our study demonstrated that MALAT1 is upregulated in HG-induced HUVECs, and inhibition of MALAT1 inhibits HG-induced apoptosis and inflammation in HUVECs by suppression of the NF-κB signaling pathway.


Asunto(s)
Apoptosis/efectos de los fármacos , Glucosa/farmacología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , ARN Largo no Codificante/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Transcripción ReIA/metabolismo , Humanos , Inflamación/inducido químicamente , Inflamación/metabolismo
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