Increased expression of galectin‐1 (Gal‐1) in carcinoma‐associated fibroblasts (CAFs) has been reported to correlate with progression and prognosis in many cancers. However, rarely have reports ...sought to determine whether high Gal‐1 expression in CAFs in gastric cancer is involved in the tumor process, and the specific mechanism by which it promotes the evolution of gastric cancer is still unknown. In this study, we cultured gastric cancer CAFs, which showed strong expression of Gal‐1, and established a co‐culture system of CAFs with gastric cancer cells. Specific siRNA and in vitro migration and invasion assays were used to explore the effects of the interaction between Gal‐1 expression of CAFs and gastric cancer cells on cell migration and invasion. We found that the overexpression of Gal‐1 in CAFs enhanced gastric cancer cell migration and invasion, and these stimulatory effects could be blocked by specific siRNA which reduced the Gal‐1 expression level. A set of cancer invasion‐associated genes were then chosen to identify the possible mechanism of Gal‐1‐induced cell invasion. Among these genes, integrin β1 expression in cancer cells was considered to be associated with Gal‐1 expression. Pre‐blocking of the integrin β1 expression in gastric cancer cells with siRNA could interrupt the invasion‐promoting effect of CAFs with high Gal‐1 expression. Furthermore, immunohistochemical assay confirmed a positive correlation between Gal‐1 and integrin β1 expression. Our results showed that high expression of Gal‐1 in CAFs might facilitate gastric cancer cell migration and invasion by upregulating integrin β1 expression in gastric cancer.
The aim of this study was to investigate whether high Gal‐1 expression in CAFs has any impact on the invasive or migratory behavior of gastric cancer cells and to explore its molecular mechanisms. And we found that that high expression of Gal‐1 in CAFs might facilitate gastric cancer cell migration and invasion by up‐regulating the integrin β1 expression in gastric cancer.
Structural color hydrogels are promising candidates as scaffold materials for tissue engineering and for matrix cell culture and manipulation, while their super‐elastic features are still lacking due ...to the irreconcilable interfere of the precursor and the self‐assembly unit. This hinders many of their practical biomedical applications where elasticity is required. Herein, hydrophilic and size‐controllable Fe3O4@poly(4‐styrenesulfonic acid‐co‐maleic acid) (PSSMA)@SiO2 magnetic response photonic crystals are fabricated as the assembly units of the structural color hydrogels by orderly packing of core–shell colloidal nanocrystal clusters via a two‐step facile synthesis approach. These units are capable of responding instantaneously to an external magnetic field with resistance to interference of ions, thus, by integrating super‐elastic hydrogels, super‐elastic magnetic structural color hydrogels can be achieved. The structural color arises from the dynamic ordering of the magnetic nanoparticles through the contactless control of external magnetic field, allowing regional polymerization of hydrogels via changing orientation and strength of external magnetic field. These regionally polymerized super‐elastic magnetic structural color hydrogels can work as anti‐counterfeiting labels with super‐elastic identification, which may be widely used in the future.
Super‐elastic magnetic structure color hydrogels are fabricated by integrating magnetic responsive photonic crystals with core‐shell structure to acrylamide hydrogels. The resultant hydrogels show brilliant structure color, controllable magnetism, and super‐elasticity. Moreover, hydrogels can be regionally polymerized by changing orientation and strength of external magnetic field. These features make them valuable in anti‐counterfeiting system.
Heterogeneous catalysts of inexpensive and reusable transition-metal are attractive alternatives to homogeneous catalysts; the relatively low activity of transition-metal nanoparticles has become the ...main hurdle for their practical applications. Here, the de novo design of a Mott–Schottky-type heterogeneous catalyst is reported to boost the activity of a transition-metal nanocatalyst through electron transfer at the metal/nitrogen-doped carbon interface. The Mott–Schottky catalyst of nitrogen-rich carbon-coated cobalt nanoparticles (Co@NC) was prepared through direct polycondensation of simple organic molecules and inorganic metal salts in the presence of g-C3N4 powder. The Co@NC with controllable nitrogen content and thus tunable Fermi energy and catalytic activity exhibited a high turnover frequency (TOF) value (8.12 mol methyl benzoate mol–1 Co h–1) for the direct, base-free, aerobic oxidation of benzyl alcohols to methyl benzoate; this TOF is 30-fold higher than those of the state-of-the-art transition-metal-based nanocatalysts reported in the literature. The presented efficient Mott–Schottky catalyst can trigger the synthesis of a series of alkyl esters and even diesters in high yields.
An optimal single-photon source should deterministically deliver one, and only one, photon at a time, with no trade-off between the source’s efficiency and the photon indistinguishability. However, ...all reported solid-state sources of indistinguishable single photons had to rely on polarization filtering, which reduced the efficiency by 50%, fundamentally limiting the scaling of photonic quantum technologies. Here, we overcome this long-standing challenge by coherently driving quantum dots deterministically coupled to polarization-selective Purcell microcavities. We present two examples: narrowband, elliptical micropillars and broadband, elliptical Bragg gratings. A polarization-orthogonal excitation–collection scheme is designed to minimize the polarization filtering loss under resonant excitation. We demonstrate a polarized single-photon efficiency of 0.60 ± 0.02 (0.56 ± 0.02), a single-photon purity of 0.975 ± 0.005 (0.991 ± 0.003) and an indistinguishability of 0.975 ± 0.006 (0.951 ± 0.005) for the micropillar (Bragg grating) device. Our work provides promising solutions for truly optimal single-photon sources combining near-unity indistinguishability and near-unity system efficiency simultaneously.
Cellular senescence is a state of cell cycle arrest characterized by a distinct morphology, gene expression pattern, and secretory phenotype. It can be triggered by multiple mechanisms, including ...those involved in telomere shortening, the accumulation of DNA damage, epigenetic pathways, and the senescence-associated secretory phenotype (SASP), and so on. In current cancer therapy, cellular senescence has emerged as a potent tumor suppression mechanism that restrains proliferation in cells at risk for malignant transformation. Therefore, compounds that stimulate the growth inhibition effects of senescence while limiting its detrimental effects are believed to have great clinical potential. In this review article, we first review the current knowledge of the pro- and antitumorigeneic functions of senescence and summarize the key roles of telomerase in the regulation of senescence in tumors. Second, we review the current literature regarding the anticancer effects of stilbene compounds that are mediated by the targeting of telomerase and cell senescence. Finally, we provide future perspectives on the clinical utilization of stilbene compounds, especially resveratrol and pterostilbene, as novel cancer therapeutic remedies. We conclude and propose that stilbene compounds may induce senescence and may potentially be used as the therapeutic or adjuvant agents for cancers with high telomerase activity.
Rhodiola rosea L., a worldwide botanical adaptogen, has been confirmed to possess protective effects of inflammatory injury for many diseases, including cardiovascular diseases, neurodegenerative ...diseases, diabetes, sepsis, and cancer. This paper is to review the recent clinical and experimental researches about the anti-inflammatory effects and the related mechanisms of Rhodiola rosea L. extracts, preparations, and the active compounds. From the collected information reviewed, this paper will provide the theoretical basis for its clinical application, and provide the evidences or guidance for future studies and medicinal exploitations of Rhodiola rosea L.
Copper-ceria is one of the very active catalysts for the preferential oxidation of carbon monoxide (CO-PROX) reaction, which is also a typical system in which the complexity of copper chemistry is ...clearly exhibited. In the present manuscript, copper–ceria catalysts with different Cu contents up to 20 wt % supported on CeO2 nanorods were synthesized by a deposition–precipitation (DP) method. The as-prepared samples were characterized by various structural and textural detections including X-ray diffraction (XRD), Vis-Raman, transmission electron microscopy (TEM), ex situ/in situ X-ray absorption fine structure (XAFS), and temperature-programmed reduction by hydrogen (H2-TPR). It has been confirmed that the highly dispersed copper oxide (CuO x ) clusters, as well as the strong interaction of Cu-O x -Ce structure, were the main copper species deposited onto the ceria surface. No separated copper phase was detected for both preoxidized and prereduced samples with the Cu contents up to 10 wt %. The fresh copper–ceria catalysts were pretreated in either O2- or H2-atmosphere and then tested for the CO-PROX reaction at a space velocity (SV) of 60 000 mL·h–1·gcat –1. The prereduced 5 and 10 wt % Cu samples exhibited excellent catalytic performance with high CO conversions (>50%, up to 100%) and O2 selectivities (>60%, up to 100%) within a wide temperature window of 80–140 °C. The in situ XAFS technique was carried out to monitor the structural evolution on the copper–ceria catalysts during the PROX experiments. The X-ray absorption near edge spectra (XANES) profiles, by the aid of linear combination analysis, identified the oxidized Cu(II) were the dominant copper species in both O2- and H2-pretreated samples after CO-PROX at 80 °C. Furthermore, the extended X-ray absorption fine structure (EXAFS) fitting results, together with the corresponding H2-TPR data distinctly determined that the highly dispersed CuO x (x = 0.2−0.5) cluster, other than the Cu–O x –Ce (x = 0.7−3.2) structure, were the crucial active species for the studied CO-PROX reaction.
Neuropeptides, as pervasive intercellular signaling molecules in the CNS, modulate a variety of behavioral systems in both protostomes and deuterostomes. Allatostatins are neuropeptides in arthropods ...that inhibit the biosynthesis of juvenile hormones. Based on amino acid sequences, they are divided into three different types in arthropods: allatostatin A, allatostatin B, allatostatin C. Allatostatin C (AstC) was first isolated from Manduca sexta, and it has an important conserved feature of a disulfide bridge formed by two cysteine residues. Moreover, AstC appears to be the ortholog of mammalian somatostatin, and it has functions in common with somatostatin, such as modulating feeding behaviors. The AstC signaling system has been widely studied in arthropods, but minimally studied in molluscs. In this study, we seek to identify the AstC signaling system in the marine mollusc Aplysia californica. We cloned the AstC precursor from the cDNA of Aplysia. We predicted a 15-amino acid peptide with a disulfide bridge, i.e., AstC, using NeuroPred. We then cloned two putative allatostatin C-like receptors and through NCBI Conserved Domain Search we found that they belonged to the G protein-coupled receptor (GPCR) family. In addition, using an inositol monophosphate 1 (IP1) accumulation assay, we showed that Aplysia AstC could activate one of the putative receptors, i.e., the AstC-R, at the lowest EC
, and AstC without the disulfide bridge (AstC') activated AstC-R with the highest EC
. Moreover, four molluscan AstCs with variations of sequences from Aplysia AstC but with the disulfide bridge activated AstC-R at intermediate EC
. In summary, our successful identification of the Aplysia AstC precursor and its receptor (AstC-R) represents the first example in molluscs, and provides an important basis for further studies of the AstC signaling system in Aplysia and other molluscs.
Parkinson's disease (PD) is a neurodegenerative disorder with no absolute cure. The evidence of the involvement of gut microbiota in PD pathogenesis suggests the need to identify certain molecule(s) ...derived from the gut microbiota, which has the potential to manage PD. Osteocalcin (OCN), an osteoblast-secreted protein, has been shown to modulate brain function. Thus, it is of interest to investigate whether OCN could exert protective effect on PD and, if yes, whether the underlying mechanism lies in the subsequent changes in gut microbiota.
The intraperitoneal injection of OCN can effectively ameliorate the motor deficits and dopaminergic neuronal loss in a 6-hydroxydopamine-induced PD mouse model. The further antibiotics treatment and fecal microbiota transplantation experiments confirmed that the gut microbiota was required for OCN-induced protection in PD mice. OCN elevated Bacteroidetes and depleted Firmicutes phyla in the gut microbiota of PD mice with elevated potential of microbial propionate production and was confirmed by fecal propionate levels. Two months of orally administered propionate successfully rescued motor deficits and dopaminergic neuronal loss in PD mice. Furthermore, AR420626, the agonist of FFAR3, which is the receptor of propionate, mimicked the neuroprotective effects of propionate and the ablation of enteric neurons blocked the prevention of dopaminergic neuronal loss by propionate in PD mice.
Together, our results demonstrate that OCN ameliorates motor deficits and dopaminergic neuronal loss in PD mice, modulating gut microbiome and increasing propionate level might be an underlying mechanism responsible for the neuroprotective effects of OCN on PD, and the FFAR3, expressed in enteric nervous system, might be the main action site of propionate. Video abstract.
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