Gastric cancer is one of the most common cancers leading to tumor-related deaths worldwide. Chicoric acid (CA) exhibits a variety of protective effects in different diseases. However, its role in ...regulating tumor progression has not been reported. Autophagy, as a conserved catabolic process, sustains cellular homoeostasis responding to stress to modulate cell fate. In the study, the effects of CA on gastric cancer were investigated. The results indicated that CA treatment markedly reduced the cell viability and induced apoptosis in gastric cancer cells, and prevented tumor growth in an established xenograft gastric cancer model. Furthermore, CA exposure significantly induced autophagy both in gastric cancer cells and tumor samples, as evidenced by the up-regulated expression of LC3II. Moreover, phosphorylated AMP-activated protein kinase (AMPK) and p70S6 kinase (p70s6k) expression were obviously promoted by CA in vitro and in vivo. Importantly, blocking AMPK activation abrogated CA-induced expression of LC3II in gastric cancer cells. In addition, endoplasmic reticulum (ER) stress in tumor samples or cells was markedly induced by CA treatment through promoting the expression of associated signals such as Parkin, protein kinase RNA-like ER kinase (PERK), activating transcription factors 4 (ATF4) and ATF6. Importantly, these effects were abolished by the inhibition of AMPK signaling. Collectively, our findings indicated that CA prevents human gastric cancer progression by inducing autophagy partly through the activation of AMPK, and represents an effective therapeutic strategy against gastric cancer development.
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Biodegradable semicrystalline polymers have attracted great interest in fundamental research as well as in technology. Biodegradability, biocompatibility with organisms, and some ...other specific characteristics are the most essential properties for this kind of material. How those properties vary in actual application, like their biodegradation rate and the degree of compatibility with corresponding cells or tissues, depends significantly on its crystalline structure. Considering biodegradable polymers are frequently employed in the form of thin film, crystallization of biodegradable polymers in thin film has attracted considerable attention during the past decades. The purpose of this feature article is to provide context as to how the crystallization of thin biodegradable polymer films can be controlled. The crystallization of polymer thin film on two kinds of substrates is summarized: (1) Crystallization on substrate without unique interaction and (2) crystallization on substrate with favored crystallographic interaction. We hope that this article will afford useful information for thin biodegradable polymer processing in different application fields.
The hypoxic tumor microenvironment was reported to be involved in different tumorigenesis mechanisms of triple-negative breast cancer (TNBC), such as invasion, immune evasion, chemoresistance, and ...metastasis. However, a systematic analysis of the prognostic prediction models based on multiple hypoxia-related genes (HRGs) has not been established in TNBC before in the literature. We aimed to develop and verify a hypoxia gene signature for prognostic prediction in TNBC patients.
The RNA sequencing profiles and clinical data of TNBC patients were generated from the TCGA, GSE103091, and METABRIC databases. The TNBC-specific differential HRGs (dHRGs) were obtained from differential expression analysis of hypoxia cultured TNBC cell lines compared with normoxic cell lines from the GEO database. Non-negative matrix factorization (NMF) method was then performed on the TNBC patients using the dHRGs to explore a novel molecular classification on the basis of the dHRG expression patterns. Prognosis-associated dHRGs were identified by univariate and multivariate Cox regression analysis to establish the prognostic risk score model.
Based on the expressions of 205 dHRGs, all the patients in the TCGA training cohort were categorized into two subgroups, and the patients in Cluster 1 demonstrated worse OS than those in Cluster 2, which was validated in two independent cohorts. Additionally, the effects of somatic copy number variation (SCNV), somatic single nucleotide variation (SSNV), and methylation level on the expressions of dHRGs were also analyzed. Then, we performed Cox regression analyses to construct an HRG-based risk score model (3-gene dHRG signature), which could reliably discriminate the overall survival (OS) of high-risk and low-risk patients in TCGA, GSE103091, METABRIC, and BMCHH (qRT-PCR) cohorts.
In this study, a robust predictive signature was developed for patients with TNBC, indicating that the 3-gene dHRG model might serve as a potential prognostic biomarker for TNBC.
By optimizing the reconfigurable intelligent surface (RIS) reflection coefficients, the channel capacity of legitimate users can be increased, thereby enhancing the anti-jamming performance of ...communication systems. However, existing studies on RIS-assisted anti-jamming assume that there is no coupling between the RIS reflection coefficients and the incident angle of electromagnetic (EM) waves, which is quite unreasonable. Therefore, we consider the effect of the incident angle of EM waves on the reflection coefficients of the RIS and propose a communication anti-jamming scheme assisted by an RIS with angular response. Specifically, a problem is formulated to optimize the RIS reflection coefficients so that the legitimate signal is amplified, but the jamming signal is attenuated, thus enhancing the legitimate channel capacity. However, the coupling of the EM incident angle and the RIS reflection coefficients causes the problem to be non-convex. To tackle this problem, we equivalently transform the RIS reflection coefficients optimization problem into a quadratically constrained quadratic programming (QCQP) problem using the complex Taylor expansion and the multidimensional complex quadratic transform (MCQT) and solve it utilizing the alternating direction method of the multipliers (ADMM) algorithm. The simulation results reveal that, compared to other schemes supported by RIS without angular response, the proposed scheme is able to achieve a significant improvement in the anti-jamming performance.
Protein misfolding is a common theme in neurodegenerative disorders including Huntington's disease (HD). The HD-causing mutant huntingtin protein (mHTT) has an expanded polyglutamine (polyQ) stretch ...that may adopt multiple conformations, and the most toxic of these is the one recognized by antibody 3B5H10. Here we show that the 3B5H10-recognized mHTT species has a slower degradation rate due to its resistance to selective autophagy in human cells and brains, revealing mechanisms of its higher toxicity.
To improve the epitaxial crystallization ability of poly(3-hexylthiophene) (P3HT) on a highly oriented polyethylene (PE) substrate, controlled solvent vapor treatment (CSVT) is employed. The ...anisotropic structures and related optical properties depend not only on the solvent used to prepare the film but also on the subsequent solvent vapor treatment pressure and time. A highly oriented PE film facilitates the “side-on” chain orientation of P3HT with its c axis parallel to the drawing direction of the PE film. The dichroic ratio (DR) of the P3HT film reflected by UV–vis spectra can reach as high as 7.1, which is much larger than the value treated by thermal annealing. Moreover, the excitation bandwidth W, indicating the effective conjugation length and molecular order, shows significant anisotropic features. Solvent used for solution processing with a high boiling point is more favorable for inducing anisotropic multiscale structures. In particular, the oriented structures lead to obvious anisotropic carrier mobility. The carrier mobility of P3HT after CSVT along the PE molecular chain direction is 7.5 times higher than that measured perpendicular to the PE chain direction. This is of great importance in fabricating anisotropic thin films of conjugated polymeric semiconductors with enhanced performance.
The millimeter-wave (mmWave) ultra-dense networks are more suitable for wireless power transfer, since the short-distance transmissions experience less pathloss and the base station (BS) packed with ...large-scale antenna arrays can achieve significant array gains. However, the secrecy performance of the simultaneous wireless information and power transfer (SWIPT) mmWave ultra-dense networks has not been investigated so far. In this paper, we consider the secure communications in downlink SWIPT mmWave ultra-dense networks, where the energy-constrained users extract energy and information from the mmWave signals in the presence of multiple eavesdroppers. First, the analytical expressions of the energy-information coverage probability are derived for both power splitting and time switching policies using stochastic geometry. Then, we derive the closed-form expressions of the secrecy probability in the presence of multiple independent or colluding eavesdroppers. Finally, the effective secrecy throughput (EST), which can measure the network energy coverage, secure, and reliable transmission performance in a unified manner, is derived. Theoretical analysis and simulation results reveal that the EST first increases and then decreases with the increasing of the transmit power, power/time splitting ratio, codeword transmission rate, and confidential information rate. Furthermore, reducing the beamwidth of the signal at BSs can decrease the information leakage and improve the EST.
Polyvinylidene fluoride (PVDF) is a known polymer with pronounced polymorphs. Among these polymorphs, the β and γ form crystals with strongest piezo- and pyro-electric activities of polymeric ...materials have attracted much attention. We report here a simple melt–recrystallization approach for producing γ-phase-rich PVDF thin films through selective melting and subsequent recrystallization. The proposed approach comprises the selective melting of both the nonpolar α-PVDF and polar γ-PVDF crystals but not the stable γ′-PVDF ones and subsequent isothermal recrystallization at 160 °C. During the recrystallization process, the nonmelting stable γ′-PVDF crystals can induce the direct γ-PVDF crystallization of the melt. In contrast, locally ordered domains survived in the molten α-PVDF crystal regions also result in a direct formation of γ-PVDF crystals. This is of great importance to fabricate high-quality thin films of γ-PVDF crystals for advanced applications.
The WRKY-type transcription factors are involved in plant development and stress responses, but how the regulation of stress tolerance is related to plant development is largely unknown. GsWRKY20 was ...initially identified as a stress response gene using large-scale Glycine soja microarrays. Quantitative reverse transcription–PCR (qRT–PCR) showed that the expression of this gene was induced by abscisic acid (ABA), salt, cold, and drought. Overexpression of GsWRKY20 in Arabidopsis resulted in a decreased sensitivity to ABA during seed germination and early seedling growth. However, compared with the wild type, GsWRKY20 overexpression lines were more sensitive to ABA in stomatal closure, and exhibited a greater tolerance to drought stress, a decreased water loss rate, and a decreased stomatal density. Moreover, microarray and qRT-PCR assays showed that GsWRKY20 mediated ABA signalling by promoting the expression of negative regulators of ABA signalling, such as AtWRKY40, ABI1, and ABI2, while repressing the expression of the positive regulators of ABA, for example ABI5, ABI4, and ABF4. Interestingly, GsWRKY20 also positively regulates the expression of a group of wax biosynthetic genes. Further, evidence is provided to support that GsWRKY20 overexpression lines have more epicuticular wax crystals and a much thicker cuticle, which contribute to less chlorophyll leaching compared with the wild type. Taken together, the findings reveal an important role for GsWRKY20 in enhancing drought tolerance and regulating ABA signalling.
Presented are the synthesis, characterizations, and reactive surface modification (RSM) of a novel nine atomic layered V4C3T
x MXene. With the advantages of the multilayered V4C3T
x MXene that can ...simultaneously support the RSM reaction and keep the inner skeleton stable, a series of amorphous Ni/Fe/V‐ternary oxide hydroxides thin layer can be successfully modified on the surface of the V4C3T
x MXene (denoted as MOOH @V4C3T
x, M = Ni, Fe, and V) without disrupting its original structure. Attributed to the in situ reconstruction of highly active oxide hydroxide layer, the nanohybrids exhibited an enhanced oxygen evolution reaction (OER) activity and excellent long‐time stability over 70 hours. In particular, a current density of 10 mA cm−2 can be reached by the nanohybrid with the optimized Ni/Fe ratio at an overpotential (η) as low as 275.2 mV, which is comparable to most of the state‐of‐the‐art OER catalysts and better than other MXene‐based derivatives. Demonstrated by the tunable physicochemical properties and excellent structural stability of these nanohybrids, we may envision the promising role of the M4X3‐based MXenes as substrates for a wide range of energy conversion and storage materials.
Presented are the novel nine atomic layered V4C3T
x MXene and its ternary metal oxide hydroxides modified derivatives (denoted as MOOH@V4C3T
x, M = Ni, Fe, and V). The nanohybrids present good OER activity and excellent long‐time stability, which demonstrates the promising future of multilayered M4X3 MXenes as substrates for the reactive synthesis of advanced energy conversion and storage materials.
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