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The Ag+ photoreduction by graphitic carbon nitride(g-CN) materials in a high concentration of Ag+ solution is reported, and a series of colorful Ag/g-CN composites is prepared and characterized. The chromatic change correlates to the carbon nitride materials synthesized at different heating temperatures(CNT, where T means heating temperature), taking advantage of the different photocatalytic activities of different CNT. The mechanism beneath this phenomenon is attributed to two factors: the particle size of Ag NPs and the coordinate effect of Ag NPs on CNT sheets. Interestingly, the multicolors of Ag/g-CN composites display only on the CNT materials synthesized from heating melamine-cyanuric acid precursor, but not on the CNT from heating pure melamine. The color of the as-prepared Ag/g-CN composites can endure the corrosion of HNO3 and ethanol, which shows a good chemical stability and may hint its application as chromophores.

Solutions or sols are commonly employed as the starting materials for the preparation of supramolecular hydrogels; however, suspension-based synthesis has been much less reported because of inhomogeneity and quick sedimentation of large particles in a suspension. Further, it remains a technical challenge to derive supramolecular aerogels directly from the parental hydrogels owing to the ease of structural collapse during water removal. Herein, we report a suspension-gel transition for the ultrafast synthesis of a new supramolecular hydrogel simply by adding AgNO3 into the aqueous suspension of cyanuric acid-melamine (CAM) aggregates. With the activation of preadded ammonia, Ag ions instantly reacted with the CAM particles, transforming into N-Ag(I)-N coordinating bonded supramolecular nanofibers; simultaneously, the suspension converted to a hydrogel without the use of polymer cross-linkers or external stimulus. Upon simple freeze-drying, a highly crystalline fibrous aerogel with a cellular network was obtained, which possessed a porosity up to 99.7% and a density as low as 4.8 mg/cm3, enabling remarkable oil uptake capacities (100 times of its weight). The supramolecular aerogel demonstrated intrinsic elasticity, which should arise from the cellular structure and elastic character of the nanofiber skeletons. Notably, the aerogel showed high compatibility to incorporate a range of external substances for further functionalization exemplified by polymeric carbon nitride (PCN, a metal-free semiconductor) included gels. The loaded PCN resulted in enhanced mechanical strength and endowed the aerogel unique photoactivity, i.e., in situ reducing Ag(I) into Ag nanoparticles upon light illumination and thus forming a plasmonic shell over the aerogel with potential applications in sensing and catalysis.

Synthetic chemical elicitors, so called plant strengtheners, can protect plants from pests and pathogens. Most plant strengtheners act by modifying defense signaling pathways, and little is known about other mechanisms by which they may increase plant resistance. Moreover, whether plant strengtheners that enhance insect resistance actually enhance crop yields is often unclear. Here, we uncover how a mechanism by which 4-fluorophenoxyacetic acid (4-FPA) protects cereals from piercing-sucking insects and thereby increases rice yield in the field. Four-FPA does not stimulate hormonal signaling, but modulates the production of peroxidases, H 2 O 2 , and flavonoids and directly triggers the formation of flavonoid polymers. The increased deposition of phenolic polymers in rice parenchyma cells of 4-FPA-treated plants is associated with a decreased capacity of the white-backed planthopper (WBPH) Sogatella furcifera to reach the plant phloem. We demonstrate that application of 4-PFA in the field enhances rice yield by reducing the abundance of, and damage caused by, insect pests. We demonstrate that 4-FPA also increases the resistance of other major cereals such as wheat and barley to piercing-sucking insect pests. This study unravels a mode of action by which plant strengtheners can suppress herbivores and increase crop yield. We postulate that this represents a conserved defense mechanism of plants against piercing-sucking insect pests, at least in cereals.

In response to infestation by herbivores, rice plants rapidly biosynthesize defense compounds by activating a series of defense-related pathways. However, which defensive compounds in rice are effective against herbivores remains largely unknown. We found that the infestation of white-backed planthopper (WBPH) Sogatella furcifera gravid females significantly increased levels of jasmonic acid (JA), jasmonoyl-isoleucine (JA-Ile) and H2O2, and reduced the level of ethylene in rice; levels of 11 of the tested 12 phenolamides (PAs) were subsequently enhanced. In contrast, WBPH nymph infestation had no effect on levels of JA, JA-Ile, ethylene and H2O2 in rice, and enhanced levels of only 2 of 12 PAs. Moreover, infestation by brown planthopper Nilaparvata lugens gravid females also affected the production of these PAs differently. Bioassays revealed that 4 PAs – N-feruloylputrescine, N-feruloyltyramine, feruloylagmatine and N1,N10-diferuloylspermidine – were toxic to newly emerged WBPH female adults. Our results suggest that WBPH- or BPH-induced biosynthesis of PAs in rice seems to be shaped primarily by the specific profile of defense-related signals elicited by the herbivore and that PAs play a role in conferring the resistance to WBPH on rice.

Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1), a long non-coding RNA (lncRNA), has been reported to link with the progression of some cancers. However, its biological functions and underlying molecular mechanisms in pancreatic cancer are largely unknown. The aim of this study was to investigate the role of lncRNA OIP5-AS1 in pancreatic cancer. Quantitative real-time PCR analysis revealed that OIP5-AS1 is highly expressed in pancreatic cancer tissues versus adjacent non-tumor tissues. In vitro functional assays showed that downregulation of OIP5-AS1 or overexpression of miR-342-3p inhibited the proliferation, decreased Ki67 expression, and induced cell cycle arrest in pancreatic cancer cells. The expression of cyclinD1, CDK4, and CDK6 was decreased by knockdown of OIP5-AS1. Moreover, we found that OIP5-AS1 acted as a miR-342-3p sponge to suppress its expression and function. Dual-luciferase assay confirmed the interaction of OIP5-AS1 and miR-342-3p and verified anterior gradient 2 (AGR2) as a direct target of miR-342-3p. Results showed that depletion of miR-342-3p abolished the inhibitory effects of OIP5-AS1 knockdown on pancreatic cancer cell growth. The expression of Ki67, AGR2, cyclinD1, CDK4, CDK6, p-AKT, and p-ERK1/2 was reversed by silencing of miR-342-3p in pancreatic cancer cells with OIP5-AS1 knockdown. Further, knockdown of OIP5-AS1 suppressed tumor growth in a xenograft mouse model of pancreatic cancer. OIP5-AS1 induced pancreatic cancer progression via activation of AKT and ERK signaling pathways. Therefore, we demonstrate that OIP5-AS1 functions as oncogene in pancreatic cancer and its downregulation inhibits pancreatic cancer growth by sponging miR-342-3p via targeting AGR2 through inhibiting AKT/ERK signaling pathway.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy. Currently, treatment strategies for PDAC are limited because its molecular characteristics have not yet been clarified. Different RET fusions have been reported in diverse solid tumors, especially in non-small cell lung cancer (NSCLC) and papillary thyroid carcinoma (PTC). Multikinase inhibitors (MKIs) such as cabozantinib, vandetanib and lenvatinib, as well as selective inhibitors of RET alterations like selpercatinib (LOXO-292) and pralsetinib (BLU-667) have been approved by the Food and Drug Administration (FDA) for patients with RET fusion-positive tumors, such as thyroid cancer, renal cell, NSCLC, and so on. However, few studies have been reported about the association between RET fusions and PDAC. ERC1-RET fusion is a rare rearrangement. To date, it has only been reported in lung cancer and thyroid cancer. Studies of ERC1-RET fusion in PDAC have not yet been explored. In this study, we reported an ERC1-RET fusion in a 60-year-old female patient with PDAC. To the best of our knowledge, this case was the first report about ERC1-RET fusion in a patient with PDAC. It is a pity that the patient refused targeted therapy for personal reasons. Our study has shed a new light on the companion diagnostics and targeted therapy for the patients with PDAC.

Organic luminogens have been widely used in optoelectronic devices, bioimaging, and sensing. Conventionally, the synthesis of organic luminogens requires sophisticated, multistep design, reaction, and isolation procedures. Herein, the products of the melt-phase condensation of benzoguanamine (BG; 2,4-diamino-6-phenyl-1,3,5-triazine) at 370-410 °C display interesting reaction-condition-dependent luminescence properties, including photoluminescence (PL) at a variety of wavelengths in the visible spectrum and quantum efficiencies (PLQE) of up to 58% in the powder form. With a simple and straightforward solvent washing procedure, the prominent blue luminescent component BG dimer was obtained in gram scale with >93% purity (96.5% purity after fractional sublimation). The BG dimer exhibited distinct aggregation-induced emission (AIE) properties. PL measurements indicate that the electronically excited state of the BG dimer undergoes efficient intramolecular nonradiative deactivation in room-temperature solution, leading to a significantly reduced PLQE (

Herein an efficient and regioselective method for the divergent synthesis of pyrimidine and dibenzo[b,f][1,4]oxazepine (DBO) derivatives from the same starting materials was developed. The selectivity can be rationally tuned via the judicious choice of reaction solvents. With 1,4-dioxane used as the solvent, 2-pyrimidinyloxy-N-arylbenzylamines (O-substituted pyrimidines) were obtained in excellent yields, whereas use of dimethyl sulfoxide (DMSO) as solvent afforded N-(2-hydroxybenzyl)-N-phenylpyrimidin-2-amines (N-substituted pyrimidines) in excellent yields, or DBO derivatives in moderate to excellent yields. The easily-accessible substrates and operational simplicity make the process suitable for further exploration. The reaction mechanism involved the SNAr reaction and Smiles rearrangement as key steps.

Room temperature Na-ion batteries (SIBs) show great potential for use as renewable energy storage systems. However, the large-scale application of SIBs has been hindered by the lack of an ideal SIBs anode material. We synthesized MoS2 on carbonized graphene-chitosan (G-C) using the hydrothermal method. The strong interaction between the MoS2 and the G-C greatly improved the electron transport rate and maintained the structural stability of the electrode, which lead to both an excellent rate capability and long cycle stability. The G-C monolith was proven to enhance the electrical conductivity of the composites and served as a matrix for uniformly dispersing active MoS2 nanosheets (NSs), as well as being a buffer material to adapt to changes in volume during the cycle. Serving as an anode material for SIBs, the MoS2-G-C electrode showed good cycling stability (527.3 mAh g−1 at 100 mA g−1 after 200 cycles), excellent rate capability, and a long cycle life (439.1 mAh g−1 at 1A g−1 after 200 cycles). Keywords: Na-ion batteries, Carbon-based materials, MoS2, Long cycle life

The electrical switch response is very desirable for developing temperature sensors and controllers. However, current switchable materials based on oxides and ceramics are limited by high transitio...

Obesity and type 2 diabetes (T2D) are both complicated endocrine disorders resulting from an interaction between multiple predisposing genes and environmental triggers, while diet and exercise have key influence on metabolic disorders. Previous reports demonstrated that 2-aminoadipic acid (2-AAA), an intermediate metabolite of lysine metabolism, could modulate insulin secretion and predict T2D, suggesting the role of 2-AAA in glycolipid metabolism. Here, we showed that treatment of diet-induced obesity (DIO) mice with 2-AAA significantly reduced body weight, decreased fat accumulation and lowered fasting glucose. Furthermore, Dhtkd1−/− mice, in which the substrate of DHTKD1 2-AAA increased to a significant high level, were resistant to DIO and obesity-related insulin resistance. Further study showed that 2-AAA induced higher energy expenditure due to increased adipocyte thermogenesis via upregulating PGC1α and UCP1 mediated by β3AR activation, and stimulated lipolysis depending on enhanced expression of hormone-sensitive lipase (HSL) through activating β3AR signaling. Moreover, 2-AAA could alleviate the diabetic symptoms of db/db mice. Our data showed that 2-AAA played an important role in regulating glycolipid metabolism independent of diet and exercise, implying that improving the level of 2-AAA in vivo could be developed as a strategy in the treatment of obesity or diabetes.

Surfactants are of great significance due to their wide use in fundamental research, industrial production, and daily lives. It remains a grand challenge to design and synthesize surfactants exhibiting reversible amphiphilicity switching. Here, we report on a "hybrid surfactant" prepared by combining an oil-soluble molecule, stearic acid, with water-dispersible Al2O3 nanofibers via chemisorption at the oil-water interface. The long carbon chain of stearic acid functions as the hydrophobic tail of the surfactant, while the inorganic nanofibers can act as the hydrophilic head. This hybrid surfactant exhibits reversible switching between hydrophilic and lipophilic states by manipulating the adsorption-desorption volume of stearic acid attached to the Al2O3 nanofibers. Therefore, the emulsions stabilized by this organic-inorganic hybrid can reversibly transform between oil-in-water and water-in-oil type. Unlike conventional approaches, no other external stimulus is needed to set the amphiphilic properties of the hybrid surfactant. As a bonus, organic-inorganic three-dimensional solid foams can be readily prepared based on the emulsion system, which demonstrates potential applications for remediation of oil spills in the environment.

6-Aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) pre-column derivatization coupled with reversed-phase liquid chromatography and diode array detection (RPLC–DAD) is one of the conventional methods for analysis of free amino acids in tea. In this article, we improved method detection sensitivity and resolution by replacing the optical detector with a mass spectrometer (MS). We also optimized the extraction process and mobile phases. Application of mass spectrometry makes co-eluting compounds easier to separate. The improved method was then successfully applied in the analysis of twenty-eight commercial tea samples with various degrees of fermentation. Umami-tasting AAs were higher in green tea than in white tea, while sweet-tasting AAs were more elevated in white tea. Principal component analysis indicated that theanine, arginine, aspartic acid and glutamic acid could be potent discriminators for tea fermentation degree.

The taste and aroma quality of Tieguanyin tea fluctuate seasonally and yearly. However, the compounds responsible for the seasonal and year variations of metabolic pattern and its sensory quality are far from clear. 60 Tieguanyin tea samples harvested in different years and seasons were analyzed by ultraperformance liquid chromatography–quadrupole time-of-flight mass spectrometry (UPLC–Q-TOF/MS) and chemometrics. Principal component analysis (PCA) explained 33.2% of the total variance, while orthogonal projection to latent structures discriminate analysis (OPLS-DA) can obtain potential metabolites with better discrimination, and with R2X and Q2 of cross-validation as 0.974 and 0.937, respectively. Subsequently, heat map analysis (HCA) visualized relationships between Tieguanyin teas with these significantly different potential metabolites by Mann-Whitney U test (p

Sirtuin 4 (SIRT4) has been reported to play a vital role in the maintenance of glutamine catabolism and adenosine triphosphate (ATP) homeostasis, but its character in hepatocellular carcinomas (HCCs) remains obscure. In this study, we observed low expression of SIRT4 in both HCC cell lines and HCCs from patients. Decreased disease-free survival time is associated with low tumor levels of SIRT4 in patients. Deficiency of SIRT4 facilitated liver tumor development and lung metastasis in xenografts and knockout (KO) mice by promoting colony formation and migration of hepatoma cells and enhancing sphere formation of HCCs. Mechanistically, SIRT4 deletion augmented mammalian target of rapamycin (mTOR) signaling by inactivating adenosine-monophosphate (AMP)-activated protein kinase alpha (AMPKα) through regulation of glutamine catabolism and subsequent AM)/liver kinase B1 (LKB1) axis. Blockage of mTOR by rapamycin or inhibition of glutaminolysis abolished the discrepancy in tumorigenic capacity between SIRT4-depleted hepatoma cells and control cells. Suppression of LKB1 or promotion of AMP by metformin also abrogated the hyperproliferative phenotype caused by SIRT4 loss, which further confirmed that the LKB1/AMPKα/mTOR axis is required in SIRT4-deficiency-promoted HCC tumorigenesis. Conclusion: SIRT4 could exert its tumor suppressive function in HCC by inhibiting glutamine metabolism and thereby increasing the adenosine diphosphate (ADP)/AMP levels to phosphorylate AMPKα by LKB1, which blocks the mTOR signaling pathway.

Salinomycin is a polyether antiprotozoal antibiotic that is widely used as an animal food additive. Some antifungal, antiparasitic, antiviral and anti-inflammatory activities have been reported for salinomycin. Recently, the anti-cancer effect of salinomycin has been demonstrated in breast cancer; however, the underlying mechanism remains unknown. The present study aimed to investigate the functional roles of salinomycin in the progression of prostate cancer cells using the DU145 and PC-3 cell lines. Western blotting and reverse transcription-quantitative polymerase chain reaction were performed to detect the expression of oxidative stress and endoplasmic reticulum stress-related molecules, and flow cytometry was performed to detect the apoptosis rate of DU145 and PC-3 cells after salinomycin treatment. The results demonstrated that salinomycin inhibited the viability and induced the apoptosis of PC-3 and DU145 cells in a dose-dependent manner. Furthermore, salinomycin increased the production of reactive oxygen species (ROS) and 8-hydroxy-2'-deoxyguanosine (8-OH-dG) and the lipid peroxidation. In addition, salinomycin induced the activation of unfolded protein response and endoplasmic reticulum stress in DU145 and PC-3 cells, as indicated by the elevated expression of binding immunoglobulin protein, activating transcription factor 4, phosphorylated eukaryotic initiation factor 2α, phosphorylated protein kinase RNA-like endoplasmic reticulum kinase and C/EBP homologous protein. In addition, salinomycin significantly downregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1, NAD(P)H quinone dehydrogenase 1 and glutamate-cysteine ligase catalytic subunit and decreased the activity of the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase in PC-3 and DU145 cells. Furthermore, the Nrf2 activator, tert-butylhydroquinone, significantly reversed the therapeutic effects of salinomycin by stimulating the Nrf2 pathway and increasing the activity of antioxidant enzymes. Taken together, these findings demonstrated that salinomycin may trigger apoptosis by inducing oxidative and ER stress in prostate cancer cells via suppressing Nrf2 signaling.

Background Acute ischemic stroke (AIS) is one of the leading causes of mortality and long-term disability worldwide. Our study aims to clarify the role of low-density lipoproteins (LDL) subclasses in the occurrence of AIS and develop a risk xprediction model based on these characteristics to identify high-risk people. Methods Five hundred and sixty-six patients with AIS and 197 non-AIS controls were included in this study. Serum lipids and other baseline characteristics including fasting blood glucose (GLU), serum creatinine (Scr), and blood pressure were investigated in relation to occurrence of AIS. The LDL subfractions were classified and measured with the Lipoprint System by a polyacrylamide gel electrophoresis technique. Results Levels of LDL-3, LDL-4 and LDL-5 subclasses were significantly higher in the AIS group compared to the non-AIS group and lower level of LDL-1 was prevalent in the AIS patients. Consistently, Spearman correlation coefficient demonstrated that sd-demonevels, especially LDL-3 and LDL-4 levels, were significantly positively correlated with AIS. Furthermore, there is a significant positive correlation between small dense LDL (sd-LDL, that is LDL-3 to 7) levels and serum lipids including total cholesterol (TC), Low density lipoprotein cholesterol (LDL-C), and Triglyceride (TG). Increased LDL-3 and LDL-4 as well as decreased LDL-1 and LDL-2 were correlated to the occurrence of AIS, even in the people with normal LDL-C levels. A new prediction model including 12 variables can accurately predict the AIS risk in Chinese patients (AUC = 0.82 ± 0.04). Conclusions Levels of LDL subclasses should be considered in addition to serum LDL-C in assessment and management of AIS. A new prediction model based on clinical variables including LDL subtractions can help clinicians identify high of AIS, even in the people with norm.

Photosynthetic bacteria (PSB) can be used in wastewater treatment to simultaneously remove pollutants and produce valuable biomass. In this study, PSB were used to treat lactic acid wastewater and produce high-value substances (protein, carotenoid and bacteriochlorophyll). The results showed that the PSB biomass increase, COD and

Room temperature switchable dielectric materials have great potential in applications such as smart sensors, energy storage and circuit protection. In this paper, a novel switchable dielectric system, Span80/HD-PET film system (SHPS), is designed and manufactured based on a “three-layer” model. And the system is built up by stacking all organic components, including the Span80/hexadecane (Span80/HD) mixture and the polyethylene terephthalate (PET) film. The SHPS shows obvious dielectric switching properties when the Span80/HD mixture goes through solid–liquid phase transition. For example, the dielectric switch can be triggered at 13.7 °C during cooling and shows good cycling stability. By changing the thickness of the PET film, the highest switching ratio can be 270.5. Besides, the switching temperature can be adjusted by changing the components of the organic mixture.

The taste and aroma quality and the price of tea are largely impacted by the geographical origin and harvest season. Tieguanyin teas differing in sites of growth and harvest season were characterized by the analysis of stable isotopes of nitrogen, carbon, hydrogen and oxygen (δ15N, δ13C, δD and δ18O). The δ15N, δ13C, δD and δ18O values were determined by elemental analyzer-isotope ratio mass spectrometry (EA-IRMS). All δ15N, δ13C, δD and δ18O values exhibited significant differences (p < 0.05) in the samples of different regional origins, whereas the δD and δ18O values highly differed (p < 0.01) between spring and autumn Tieguanyin teas. With the aid of chemometrics, orthogonal projection to latent structures discriminate analysis (OPLS-DA) achieved 96.08% recognition rate for Tieguanyin teas from different regions, whereas stepwise linear discriminant analysis (SLDA) allowed 100% differentiation. Moreover, principal component analysis (PCA) and hierarchical cluster analysis (HCA) methods revealed excellent discrimination possibilities for the teas according to seasonal variations. Additionally, our study presented a good alternative to differentiate teas from different sites of growth and harvest seasons and also to address the quality control and food authenticity concerns.

Aim: To investigate the association of small dense low-density lipoprotein cholesterol (sdLDL-C) and acute ischemic stroke (AIS) in terms of risk, severity, and outcomes. Prediction models were established to screen high-risk patients and predict prognosis of AIS patients. Methods: We enrolled in this study 355 AIS patients and 171 non-AIS controls. AIS was subtyped according to TOAST criteria, and the severity and outcomes of AIS were measured. Blood glucose and lipid profiles including total cholesterol, triglyceride, and lipoproteins were measured in all patients using automatic measure. Lipoprotein subfractions were detected by the Lipoprint LDL system. Results: As compared with the non-AIS control group, the AIS group had higher sdLDL-C levels. Pearson correlation analysis revealed that the sdLDL-C level and risk of AIS, especially non-cardioembolic stroke, were positively correlated. The area under the curve of sdLDL-C for AIS risk was 0.665, better than that of other lipids. Additionally, the sdLDL-C level was significantly correlated with AIS severity and bad outcomes. A logistic regression model for assessing the probability of AIS occurrence and a prognostic prediction model were established based on sdLDL-C and other variables. Conclusions: Elevated levels of sdLDL-C were associated with a higher prevalence of AIS, especially in non-cardioembolic stroke subtypes. After adjustment for other risk factors, sdLDL-C was found to be an independent risk factor for AIS. Also, sdLDL-C level was strongly associated with AIS severity and poor functional outcomes. Logistic regression models for AIS risk and prognosis prediction were established to help clinicians provide better prevention for high-risk subjects and monitor their prognosis.

Pickering emulsions are emulsions stabilized by solid particles located at surfaces/interfaces of liquid droplets that have promising applications for drug delivery and in nanomaterials synthesis. Direct observation of Pickering emulsions can be challenging. Normally, cryoelectron microscopy needs to be used to better understand these types of emulsion systems, but cryofreezing these emulsions may cause them to lose their original morphologies. In this work, we demonstrate that graphitic carbon nitride (g-C3N4) can stabilize oil-in-water (o/w) emulsions, with hexane illustrated as a typical oil phase. The g-C3N4-stabilized emulsions can act as an excellent platform for in situ study of emulsifying behavior from the mechanical point of view. Owing to its large lateral size and blue, stable fluorescence, the locations and motions of the g-C3N4 stabilizer can be finely in situ monitored by light microscopy, fluorescence microscopy, and confocal microscopy. Accordingly, we illustrate two stabilizing configura...

The room-temperature switching effect is of great interest for many applications, such as smart buildings, sensors, thermal energy storage and automatic temperature control. In this paper, we report a room-temperature switchable carbon nanotube (CNT)/hexadecane composites. Electrical conductivity, thermal conductivity and permittivity of the CNT/hexadecane composites can be regulated around 18°C and the maximal switching ratio reaches 5 orders of magnitude, 3 times and 106.4, respectively. The switching behavior of composites is caused by rearrangement of the carbon nanotube fillers in hexadecane matrix during liquid-solid phase transition. It is found that surface modification is necessary to improve dispersion stability. Effects of filler properties on switching behaviour are also discussed.

Oxidative stress results in various pathologies and as consequence antioxidant agents have attracted uninterrupted attention. In this paper, a novel series of indole-3-carboxamide derivatives (6a–6l) were designed and synthesized based on the melatonin structure as novel antioxidants. All of them were evaluated for the antioxidant activities in vitro against human neuroblastoma SH-SY5Y cell line using H2O2 radical scavenging assay. The target compounds 6a, 6f and 6i indicated better activities than the positive control, ascorbic acid, and 6a exhibited the best antioxidant activity. In addition, the structure-activity relationships of the target compounds were also preliminarily summarized based on the obtained experimental data.

Three simple fluorescence turn-on sensors have been designed for the selective detection of adenosine (AD) based on a boronic acid receptor and a coumarin fluorophore (NLC, NJC, NDC). In the absence of AD, the fluorescence emission intensity of the sensors was relatively weak due to the effective electronic transfer from the to the coumarin to the boronic acid moiety. When the AD was introduced into the system, an obvious fluorescence enhancement was observed. It was attributed to the boronic acid covalently binding to the cis-diol unit of the AD resulting in the electronic transfer process being inhibited. Under the optimal conditions, these fluorescent sensors not only could perform good selectivity and fast response ( 30 s), but also show good water solubility. Finally, the proposed sensor NLC has been utilized for the AD determination in urine without any complicated pretreatment and the recovery was in the range of 95–103%. As a result, it is promising for application on the AD detection in complex biological samples. Moreover, there are no small molecular sensors detecting AD have been reported, yet, it is promising for providing a new platform to detect AD by small molecular sensor.

Background: As reported EGFR is a sialoglycoprotein with tyrosine kinase activity involved in control of cellular survival, multiplication, differentiation and metastasis. Dysregulation or aberrant expression of EGFR has been implicated in cell transformation and having oncogenic roles in a number of human cancers. Therefore EGFR has become a significant target for developing targeted therapy for cancer. Methods: A novel series of indole-3-carboxamide derivatives as EGFR inhibitors were designed, synthesized and evaluated for the anticancer activity in vitro against three EGFR high-expressed cancer cell lines (A549, HeLa, and SW480), one EGFR low-expressed cell line (HepG2) and one human liver normal cell line (HL7702) by MTT assay. Results: The target compounds 6c, 6f, 6i, 6j, 6l, 6r, 6u and 6x exhibited potent anticancer activities against the three tested cancer cell lines and weak cytotoxic effects on HepG2, which imply that the target compounds are probably effective in inhibiting EGFR. And they also did not show measurable activities in HL7702, which imply the target compounds are likely to overcome the nonspecific toxicity against normal cells. Particularly, the target compound 6x indicated equal to the positive control erlotinib. In addition, molecular docking studies demonstrated the target compound 6x may be the potential inhibitor to EGFR. Conclusion: A new EGFR inhibitor scaffold and a preliminary discussion on their SARs provide promising opportunities to guide further research on indole-3-carboxamide derivatives as novel anticancer agents.

Artificial synaptic devices are the essential components of neuromorphic computing systems, which are capable of parallel information storage and processing with high area and energy efficiencies, showing high promise in future storage systems and in-memory computing. Analogous to the diffusion of neurotransmitter between neurons, ion-migration-based synaptic devices are becoming promising for mimicking synaptic plasticity, though the precise control of ion migration is still challenging. Due to the unique 2D nature and highly anisotropic ionic transport properties, van der Waals layered materials are attractive for synaptic device applications. Here, utilizing the high conductivity from Cu+ -ion migration, a two-terminal artificial synaptic device based on layered copper indium thiophosphate is studied. By controlling the migration of Cu+ ions with an electric field, the device mimics various neuroplasticity functions, such as short-term plasticity, long-term plasticity, and spike-time-dependent plasticity. The Pavlovian conditioning and activity-dependent synaptic plasticity involved neural functions are also successfully emulated. These results show a promising opportunity to modulate ion migration in 2D materials through field-driven ionic processes, making the demonstrated synaptic device an intriguing candidate for future low-power neuromorphic applications. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version J.C. (Jiangang), C.Z., and G.C. contributed equally to this work. Z.L. acknowledges the support from National Research Foundation Singapore programme NRF-CRP21-2018-0007 and NRF-CRP22-2019-0007, Singapore Ministry of Education via AcRF Tier 3 Programme “Geometrical Quantum Materials” (MOE2018-T3-1-002), AcRF Tier 2 (MOE2016-T2-1-131), and AcRF Tier 1 RG4/17 and RG7/18. G.C. acknowledges the support from China Postdoctoral Science Foundation (2019M663463). P.M. acknowledges the support from Postdoctral Innovatiove Talent Supporting Program (BX20190060). F.L. acknowledges the support from the National Natural Science Foundation of China (62074025) and the National Key Research & Development Program (2020YFA0309200), the Applied Basic Research Program of Sichuan Province (2020ZYD014, 2021JDGD0026), and the Sichuan Province Key Laboratory of Display Science and Technology.

A novel series of benzo[d]thiazole-2-carboxamide derivatives have been de novo designed based on virtual screening methods. The target compounds were synthesized and evaluated for the cytotoxicity against epidermal growth factor receptor high-expressed cancer cell lines (A549, HeLa, and SW480), epidermal growth factor receptor low-expressed cell line (HepG2) and human liver normal cell line (HL7702). Several target compounds have showed moderate to excellent potency against A549, HeLa, and SW480 and weak cytotoxic effects against HepG2, which implies they are probably epidermal growth factor receptor inhibitors. And scarcely did they exhibit any activities against HL7702, which signifies they are likely to overcome the nonspecific toxicity against normal cells. Especially, the compound 6-[2-(diethylamino)-2-oxoethoxy]-N-(furan-2-ylmethyl)benzo[d]thiazole-2-carboxamide (6i) was identified as a promising agent, exhibiting the most potent cytotoxic activities with IC50 values of 4.05, 12.17, 6.76 μM against the A549, HeLa, and SW480 cell lines, respectively.

In this work, we report on the synthesis of a free-standing, macroscopic robust supramolecular membrane by introducing silver-nitrogen coordinate bonding into preorganized, supramolecular hydrogen-bonded cyanuric acid-melamine (CAM) crystals. With the assistance of ammonia, silver ions competitively replace two of the three hydrogen atoms from cyanuric acid resulting in the transformation from short CAM nanorods to long CAM-Ag nanofibers (length over 1000 μm), accompanied by tautomerization of cyanuric acid. The single crystal structure of the CAM-Ag nanofibers is solved in the space group P1, with the asymmetric unit containing eight silver atoms, four melamine and four cyanuric acid molecules, which generate 1D coordination polymer chains consisting of alternating melamine and dianionic cyanurate ligands linked via silver-nitrogen bonds. The presence of interchain hydrogen bonds results in the expansion of the supramolecular network into undulating 2D sheets, which then stack into a 3D network via a series of intersheet hydrogen bonds and π-π interactions. Significantly, the CAM-Ag nanofibers spontaneously assemble into a free-standing membrane, with lateral size up to square centimeters and thickness of 30 μm. The membrane shows high flexibility and mechanical strength, owing to the improved flexibility of the CAM-Ag nanofibers with bonded chain structure, and can be reversibly and repeatedly bent over 90 degrees. Remarkably, the CAM-Ag membrane demonstrates distinct optical transmittance being shortwave IR transmissive but impenetrable to UV and visible light.

The Pt (II)⋅⋅⋅Cl interactions between trans-Pt (NH3)2X2/cis-Pt (NH3)2X2 (X=OH, F, Cl, Br) and ClF were constructed and studied by Moller-Plesset perturbation theory (MP2) method. The metal Pt (II)-complex could act as the halogen bond acceptor, the Pt (II)⋅⋅⋅Cl interaction strength depends on the nature and the configuration of platinum (II) ligands: the metal halogen-bonding interactions in trans-Pt (OH)2(NH3)2⋅⋅⋅ClF/cis-Pt (OH)2(NH3)2⋅⋅⋅ClF are obviously stronger than those in trans-PtX2(NH3)2⋅⋅⋅ClF/cis-PtX2(NH3)2⋅⋅⋅ClF (X=F, Cl, Br); the halogen bonds in cis-complexes are somewhat stronger than those in respective trans-complexes. This particular Pt (II)⋅⋅⋅Cl interactions is much stronger than hydrogen bond and has some degree of covalent character. For the Pt (II)⋅⋅⋅Cl interactions, the charge transfer between the related molecular orbitals of PtX2(NH3)2 and ClF are obvious, which is consistent with that the exchange energy contributes most to the total interaction energy. The stronger of the Pt (II)⋅⋅⋅Cl interactions, the more decreased electron density outside Pt (II) facing the chlorine atom, and the more increased electron density between Pt (II) and Cl, indicating that the polarization effect plays an important role in the formation of the Pt (II)⋅⋅⋅Cl interactions.

Potassium has been extracted successfully from biotite by Ba2+/K+ ion exchange. The potassium release rate increased along S-curve versus reaction time. The maximum of potassium release rate was about 96 %. Powder X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy were used to characterize the obtained samples to reveal the exchanging behavior and structural transformation. The results showed that after treated with Ba(NO3)2 four times the original biotite transformed to vermiculite-type hydrated Ba-mica. The (001) basal plane was expanded from 1.000 nm of biotite to 1.221 nm of hydrated Ba-mica. Because of the “vacancy effect,” the Ba2+ has two different statuses, causing the structural water vibration of vermiculite-type hydrated Ba-mica split. The edge of vermiculite-type hydrated Ba-mica was crimped compared with the flat edge of original biotite. The (001) basal plane of dehydrated Ba-mica was also split, supporting the “vacancy effect.”

Electrical and thermal switchable materials are of interest in temperature regulation, circuit protection, sensors and other field. In this paper, functionalized carbon black (CB)/octadecane composites were synthesized for room temperature electrical and thermal switch. With these composites, large contrast ratios of electrical conductivity (EC) and thermal conductivity (TC) are achieved around the phase transition temperature (28–29 °C). The corresponding contrast ratios of EC and TC reach 4.3 × 105 and 3.3 times, respectively. The composites show remarkable stability and durability during the cycling experiments. The mechanisms of good stability and high EC contrast ratio are discussed as well.

By a cation-exchange method, potassium was extracted from muscovite using hydrochloric acid as a motivator and barium ion as a potassium-exchange agent. The influences of various extracting conditions, such as initial barium concentration, reaction temperature, and reaction time, on cationic exchange were investigated at a constant pH value. Mineral phases of the treated samples were also investigated by X-ray diffraction and a significant inflective change of the interlayer spacing was detected. In addition, the significant inflective changes of stretching bonds of hydroxyl and silicon–oxygen were also discovered by Fourier transform infrared spectroscopy analysis. ‘Vacancy effect’ and ‘Radius effect’ were proposed as two representative extraction mechanisms to interpret the synchronous inflective changes of the interlayer spacing and the stretching bonds of hydroxyl and silicon–oxygen.

Pinus densiflora var. zhangwuensis grows fast, and its drought and salinity resistance are better than Pinus sylvestris var. mongolica. We compared cold hardiness and mechanisms of cold hardiness between the two species, to provide a theoretical basis for promoting and applying P. densiflora var. zhangwuensis in cold regions. A cold stress experiment was carried out on 3-year-old plantlets of P. densiflora var. zhangwuensis and P. sylvestris var. mongolica after hardening at five temperature regimes, 5, −10, −20, −40, and −60 °C, respectively. Some indices of needle samples for both species were measured, such as relative conductivity (REL), maximum photochemical efficiency (Fv/Fm), malondialdehyde (MDA), catalase (CAT), proline (Pro), soluble sugar (SS), and stomata density. REL and MDA values of both species after hardening had the same trend of increasing, but the trend was opposite in Fv/Fm value with increasing cold stress. Compared with P. sylvestris var. mongolica, the P. densiflora var. zhangwuensis had smaller increases in REL and MDA, and a smaller decline in Fv/Fm during cold stress. Compared to the control, REL growth of P. densiflora var. zhangwuensis and P. sylvestris var. mongolica at −60 °C were 0.41 and 0.60, and MDA growth was 29.94 mol g−1 FW and 47.80 mol g−1 FW, and Fv/Fm declines were 0.08 and 0.27. Half-lethal temperatures (LT50) calculated by logistic equation for P. densiflora var. zhangwuensis and P. sylvestris var. mongolica were −58.23 and −50.34 °C, respectively. These data suggest that cold resistance of P. densiflora var. zhangwuensis is stronger than that of P. sylvestris var. mongolica. Cold-resistance mechanisms of the two species differed. In response to cold stress, P. sylvestris var. mongolica had strong osmotic adjustment ability because of higher Pro and SS content, while P. densiflora var. zhangwuensis had strong antioxidant ability due to stronger CAT activity. Stomata density and diameter of P. densiflora var. zhangwuensis were smaller, as were single leaf area and number of leaves per plant, both characteristics promoting survival in a cold environment. Greater shoot height and total biomass of seedlings of P. densiflora var. zhangwuensis might be another reason for its stronger cold tolerance.

A transition metal-free and regioselective total synthesis of 6-methylellipticine, a potent anticancer agent, was developed. This synthetic approach mainly involved two key reactions: a direct amination of multi-functional phenol via an alkylation-Smiles rearrangement protocol, and an intramolecular C–H bond arylation reaction promoted by potassium tert-butoxide. These reactions resulted in the formation of two key intermediates, diarylamine and carbazole derivative, under transition metal-free conditions. The last cyclization afforded the target product 6-methylellipticine.

A novel hydrogen storage material Mg2Ni has been studied by the first-principle methods based on plane-wave pseudopotential theory. The corresponding electronic structure of hydrogen storage materials, Mg2Ni, Mg12Ni5M1(M = Mn and Cu), and their hydride have also been investigated. The enthalpy of hydrogenation reaction is-65.07kJ/mol (H2), which is in line with the experimental results. The stability of the new hydride alloy increased by substitution with Cu, and a small amount of alternative might be preventing powdering after several cycles. The Mn atom substitutes Ni atom of hydride alloy which would weaken the H-Ni bond, and the temperature of desorption decreased. The results will play an important role in practical application.

The search for the effective and safe α-glucosidase and α-amylase inhibitors from Actinomycetaceae being antidiabetic agents is actual problem. Twenty one Streptomyces spp. of soil samples collected from different places of China were screened for the ability to produce this kind of inhibitory activities. Fermentation broth of isolated strains had absorbance between 350–190 nm. The Streptomyces strains PW003, ZG636, and ZG731 were characterized by special absorption at 280, 275, and 400 nm, respectively. Ten of the collected actinomycete strains had the ability to inhibit α-glucosidase or/and α-amylase and the fermentation broth of the same strain had inhibitory activity varied greatly depending on the enzyme source. In the process to screen the leading compounds used as antidiabetic agents, human α-glucosidase and α-amylase were revealed as the best used in trail compared with the same enzymes from other sources. Active α-glucosidase inhibitor was isolated from Streptomyces strain PW638 fermentation broth and identified as acarviostatin I03 by MS and NMR spectrometry. Its IC50 value was 1.25 and 12.23 μg/ml against human intestinal N-terminal maltase-glucoamylase and human pancreatic α-amylase, respectively.

This paper presents a novel approach for preparing titanium dioxide nanotube arrays (TNTs) loaded with highly dispersed Br through an ultrasound aided photochemical route. The content of Br doped on the arrays was controlled by changing the concentration of NaBr and the ultrasound time. The Br doped TiO2nanotube arrays were characterized by SEM, XRD and UV–Vis spectrum. Doping the bromine did not basically affect the morphology of the surface of the TNTs, but part of the anatase phase transformed into rutile phase, which led to the formation of the mixed crystal and increased the photocatalytic activity. The results showed that Br doping significantly enhanced the photocatalytic degradation rate of titanium dioxide nanotube arrays under UV-light irradiation. The main factors which affected photocatalytic degradation of sugar wastewater were the illumination time and pH. The results showed that the longer the exposure time was, the initial pH of wastewater was more favorable to photocatalytic degradation of the sugar wastewater for the Br-TiO2nanotube arrays, and compared to undoped TiO2nanotube arrays Br doped TiO2nanotube arrays had better photocatalytic properties.

In this letter, γ-Zn3(PO4)2: Mn2+ phosphors have only one emission band centered at 620 nm while two emission bands are observed in γ-Zn3(PO4)2: Mn2+, Ga3+, which are respectively centered at 507 nm and 620 nm. The spectral overlap between the green emission band and the excitation band monitored at 620 nm, which supports the occurrence of the energy transfer from Mn2+ (CN=4) to Mn2+ (CN=6), has been studied. The influence of Ga3+ ions on luminescence and long lasting phosphorescence properties of Mn2+ in phosphor γ-Zn3(PO4)2: Mn2+, Ga3+ are also investigated. It is found that the green/red phosphorescence performance of Mn2+ ion such as brightness and duration is largely improved when Ga3+ ion is co-doped into the matrix in which Mn2+ ion acts as luminescent center and Ga3+ ion plays an important role of electron trap.

The new N-containing maltooligosaccharides GIB-638 were isolated and purified from the culture filtrate of Streptomyces fradiae PWH638 using the chemoenzymatic method. Its physicochemical properties, liquid chromatographic behaviour and spectroscopic data were similar to the reported compounds acarviostatin I03 with a molecular weight of 969 Da. Its structures were determined by spectroscopic methods, including ESI multistage mass spectrometry and two-dimensional NMR techniques. It was the first time isolated from S. fradiae PWH638 and exhibited effective inhibitory activity against human maltase-glucoamylase. The inhibition constants for GIB-638 against MGAMnt and MGAMct were 47.8, 24.03 μmol, respectively. It also could inhibit the maltose hydrolysis and glucose transfer in the in vitro-everted intestine model. The results from this study could provide the scientific evidence for it to use in the treatment of diabetes in medicine.

A magnetically separable photocatalyst silver vanadates@SiO2/Fe3O4 was prepared by hydrothermal process. The prepared sample was composed of mixed phases of a–Ag3VO4 and Ag4V2O4, and the main phase was a–Ag3VO4. The bandgap of the synthesized sample was 2.2 eV. In the degradation of methyl orange (MO) solution under the visible light (l>420 nm), the silver vanadates@SiO2/Fe3O4 showed high photocatalytic activity in two-cycle photocatalytic test.

Porous silicon multilayer structures have remarkable optical and morphological properties that can be exploited for biosensing. In particular, a high internal surface area (>100 m(2)/cm(3)) and a linear response profile to changes in the dielectric environment enable fabrication of sensitive devices and a straightforward quantitation of the optical response. These essential operating characteristics are illustrated for p+ mesoporous silicon (pore diameter 15-20 nm) optical microcavities. A series of devices were prepared to permit the immobilization of glutathione-S-transferase ( approximately 50 kDa) within the porous matrix. Enzyme activity was exploited as an indirect means to quantitate the amount of protein immobilized. Activity was positively correlated with the optical sensor response. However, at high enzyme load the activity becomes nonlinear while the microcavity response remains linear. These data were used to determine the transduction limit (minimum amount of protein required to transduce an optical response), which is reported as areal mass sensitivity ranging between 50 and 250 pg/mm(2). This value is considered in context with the dynamic range of the bulk sensitivity, defined as the magnitude of the wavelength shift per refractive index unit, which was measured as a function of microcavity design parameters. This work has uncovered key parameters that can be tuned to improve the detection limit of this sensor modality. Because of the ever increasing number of emerging new biosensor technologies, defining sensor detection limits has become an ambiguous topic and a need exists to standardize measurements and sensitivity units. For chip-based devices, it seems appropriate to report sensitivity in terms of the minimum number of grams of bound target per surface area.

A method based on ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was established for the determination of fipronil and its metabolites in feeds. Sodium chloride was added to the samples after the ultrasonic extraction of pure water and acetonitrile, and then cleaned up by the QuEChERS method. The target analytes were separated on a Waters HSS T3 C18 column using methanol and water as mobile phases with gradient elution, and detected by a MS/MS system under negative electro-spry ionization (ESI-) and the multiple reaction monitoring (MRM) mode. The limits of detection (LODs) were 0.05 μg/kg, and the limits of quantification (LOQs) were 0.2 μg/kg. The linear correlation coefficients were more than 0.9998. The average recoveries ranged from 92.3% to 105.4% with RSDs no more than 2.3%. This method is suitable for the identification of fipronil and its metabolites in feeds because of its simplicity and high sensitivity.

Field electron emission from carbon nanotubes shows promising application potential in devices. Low adhesive bonding strength between the carbon nanotubes and the substrate presents a practical challenge in environments such as high field emission current density. In this paper, we report on the performance of a carbon nanotube microbundle attached to a tungsten needle by a uniform glue layer. The device is easily fabricated without complex fixture and possesses a complete array structure. After curing the glue in air, the adhesive strength between the carbon nanotubes and the needle is over 2000 N/cm2. Field emission measurements demonstrate that the maximum current density of the emitters is over 20 A/cm2 under a low applied field (

Room-temperature switchable dielectric materials are of interest for many applications, including solar energy storage, smart switches, automatic filters, and next-generation sensors. Here, a temperature-triggered dielectric switchable nanocomposite by dispersing octadecylamine-grafted multiwalled carbon nanotubes (ODA-MWCNTs, for short) into hexadecane is reported. The composite has low permittivity at molten state and high permittivity at frozen state, and the permittivity switch is triggered around 18 °C. The highest permittivity contrast ratio reaches 106.4 at 2.0% CNT volume fraction. The composite shows frequency-sensitive and temperature-ramping-rate-sensitive properties. Further investigation indicates that the permittivity switch is caused by the change of the ODA-MWCNT percolating networks during phase transition.

// Heather G. Hambright 1 , Peng Meng 1, 6 , Addanki P. Kumar 1, 2, 3, 4, 5 , Rita Ghosh 1, 2, 3, 4 1 Department of Urology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229, USA 2 Department of Pharmacology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229, USA 3 Department of Molecular Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229, USA 4 Cancer Therapy and Research Center, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229, USA 5 South Texas Veterans Health Care System, San Antonio, Texas, 78229, USA 6 Life Sciences Division, Lawrence Berkley National Laboratory, Berkley, California, 94710, USA Correspondence to: Rita Ghosh, e-mail: ghoshr@uthscsa.edu Keywords: Reactive oxygen species, oxidative stress, mTORC1, melanoma, Nexrutine R Received: December 22, 2014 Accepted: January 09, 2015 Published: January 29, 2015 ABSTRACT Elevated oxidative stress in cancer cells contributes to hyperactive proliferation and enhanced survival, which can be exploited using agents that increase reactive oxygen species (ROS) beyond a threshold level. Here we show that melanoma cells exhibit an oxidative stress phenotype compared with normal melanocytes, as evidenced by increased total cellular ROS, KEAP1/NRF2 pathway activity, protein damage, and elevated oxidized glutathione. Our overall objective was to test whether augmenting this high oxidative stress level in melanoma cells would inhibit their dependence on oncogenic PI3K/AKT/mTOR-mediated survival. We report that Nexrutine R augmented the constitutively elevated oxidative stress markers in melanoma cells, which was abrogated by N-acetyl cysteine (NAC) pre-treatment. Nexrutine R disrupted growth homeostasis by inhibiting proliferation, survival, and colony formation in melanoma cells without affecting melanocyte cell viability. Increased oxidative stress in melanoma cells inhibited PI3K/AKT/mTOR pathway through disruption of mTORC1 formation and phosphorylation of downstream targets p70S6K, 4EBP1 and rpS6. NAC pre-treatment reversed inhibition of mTORC1 targets, demonstrating a ROS-dependent mechanism. Overall, our results illustrate the importance of disruption of the intrinsically high oxidative stress in melanoma cells to selectively inhibit their survival mediated by PI3K/AKT/mTOR.