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A novel fluorescent probe (Zr(CDs-COO)(2)EDTA) has been designed for fluoride ion (F(-)) content detection based on the competitive ligand reactions carried out between the carboxylate groups (-COOH) on the surface of the luminescent carbon dots (CDs) and F(-) coordinated to Zr(H(2)O)(2)EDTA. The strong and stable fluorescence signal of this probe was quenched upon the addition of F(-) as a result of the formation of the non-fluorescent complex Zr(F)(2)EDTA, due to the stronger affinity of F(-) than the -COOH in the CDs to Zr(IV). The fluorescence change (ΔF) in this process was linear with respect to the content of F(-), ranging from 0.10 μM to 10 μM. The probe has been applied to F(-) detection in toothpaste and water samples with satisfactory results. Moreover, the mechanism of this Zr(H(2)O)(2)EDTA modulated fluorescent probe for the detection of F(-) was also discussed.

However, in most cases, stoichiometricamounts peroxides like H 2 O 2 and tertbutyl hydroperoxide (TBHP) were used as exogenous oxidizing reagents and oxygen sources, [2] resulting in massive waste and an increase in costs. [3] The strategy that water serves as the oxygen source to produce high-value organic chemicals has drawn more attention due to its low price and cleanliness, [4] yet its inertia under ambient temperatures leads to more energy consumption in practical working conditions. Electrochemical methods with waste-free electrons as redox agents provide a green and mild pathway to watermediated oxidation of organics, [5] where the balance between the oxidation of organics and the competitive oxygen evolution reaction (OER) is deemed as the main problem. [6] Inspired by the tandem catalysis tactic, turning this competition between the OER and the selective oxidation of styrene to benzaldehyde into cooperation should be feasible, but it has rarely been achieved.Single-atom catalysts (SACs) meet with great favor in electro catalysis for their superior activity, higher metal-utilization efficiency, and enhanced selectivity. [7] In the past decade, enormous encouraging SACs have been created and utilized to catalyze the oxygen reduction reaction, the OER, and other heterogeneous reactions. [8] However, the activity of SACs often suffers the limit for complex reactions with multiple intermediates, because the single site is not able to catalyze efficiently all the reactions in the whole system. [9] Although introducing extra active centers into SACs has the potential to break this limit, [10] spatiotemporal transfer of intermediates over catalytic sites and inherent synergetic mechanisms remain unexplored, thus leading to a low product yield and undesirable side reactions. Besides, insufficient cognition on the reconstruction of the catalytic sites in working conditions also increases the difficulty of their design. Therefore, constructing active sites with a specific function to catalyze complex reactions in a tandem system still confronts a great challenge.Herein, we fabricate a single-atom catalyst with Cr atoms atomically dispersed at CoSe 2 support (Cr 1 /CoSe 2 ), in which Co and Cr sites are endowed with a specific function to oxidize water and styrene respectively. Especially, the anchored Cr single atoms could not only serve as the active sites for the Electrocatalytic oxidation of organics using water as the oxygen source is a prospective but challenging method to produce high-value-added chemicals; especially, the competitive oxygen evolution reaction (OER) limits its efficiency. Herein, a tandem catalysis strategy based on a single-atom catalyst with Cr atoms atomically dispersed at a CoSe 2 support (Cr 1 /CoSe 2 ) is presented. Thereinto, Co and Cr sites are endowed with a specific function to activate water and styrene respectively, and the competition between the OER and styrene oxidation is turned into mutual benefits via cooperated active sites. Under a potential of 1.6 V Ag/AgCl , exce...

The metastasis-associated lung adenocarcinoma transcription 1 (MALAT1) is a highly conserved long non-coding RNA (lncRNA) gene. However, little is known about the pathological role of lncRNA MALAT1 in glioma. In the present study, we explored the expression level of lncRNA MALAT1 in primary glioma tissues as well as in U87 and U251 glioma cell lines. Using qRT-PCR, we found that the expression of lncRNA MALAT1 was significantly increased in glioma tissues compared with that of paracancerous tissues. Meanwhile, the expression of MALAT1 was highly expressed in U98 and U251 cells. In order to explore the function of MALAT1, the expression of MALAT1 was greatly reduced in U87 and U251 cells transfected with siRNA specifically targeting MALAT1. Consequently, cell viability of U87 and U251 cells were drastically decreased after the knockdown of MALAT1. Concomitantly, the apoptosis rate of the two cell lines was dramatically increased. Furthermore, the expression levels of some tumor markers were reduced after the knockdown of MALAT1, such as CCND1 and MYC. In summary, the current study indicated a promoting role of MALAT1 in the development of glioma cell.

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Gold nanoclusters (AuNCs) protected by bovine serum albumin (BSA) can emit red photoluminescence under illumination by ultraviolet light. The luminescence of the BSA-AuNCs was quenched when Cu 2+ chelated with glycine in the BSA chain and generated BSA-AuNCs-Cu 2+ , while the luminescence of the BSA-AuNCs restored when pyrophosphate ion (P 2 O 7 4À , PPi) was added and chelated with Cu 2+ , resulting in Cu 2+ being removed from the surface of BSA-AuNCs. Bearing this in mind, herein we present a novel BSA-AuNCs-Cu 2+ fluorescent sensor for PPi detection. This environmentally-friendly, simple, rapid and selective fluorescent sensor possesses a wide linear range (0.16-78.1 mM) and a high sensitivity (the limit of detection (LD) is 0.083 mM), which could also determine PPi in the effluent of copper plating with the results consistent with those obtained by absorptiometry. Furthermore, the morphologies of BSA-AuNCs, BSA-AuNCs-Cu 2+ and BSA-AuNCs-Cu 2+ -PPi were characterized by high resolution transmission electron microscopy (HRTEM). The mechanism of the proposed assay for PPi detection has been discussed. Experimental Apparatus and reagentsA BP-211D electronic analytical balance (Shanghai Mettler-Toledo Instruments Co., Ltd.

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Background Treatments based on the inhibition of pivotal signals of cancer stem cells (CSCs) are on a promising track. Recent studies have shown that targeting CSCs with broader immune‐based therapeutic methods, for example, the anti‐CD47 treatment, may serve as a more potent strategy for eliminating these intractable cells. We aimed to explore the prognostic effects of CD47/CD133 and the potential therapeutic significance of CD47 in esophageal squamous cell carcinoma (ESCC). Methods Immunohistochemistry was employed to identify the characteristics of CD47 and CD133 in 26 pairs of tumor tissues and adjacent non‐tumor tissues and 136 ESCC tissues. Kaplan‐Meier analysis and Cox proportional hazards models were built for estimating the prognostic values of CD47 and CD133 expression and their combined stemness index. Sphere formation assays were undertaken to explore the effects of CD47 inhibition on primary human ESCC CSCs. Results Results conclude that CD47 and CD133 expression is increased in tumor tissues as compared to adjacent non‐tumor tissues. A positive correlation between CD47/CD133 expression and differentiation was found in 136 ESCC patients. Survival analysis indicated that patients with high CD47 or CD133 expression exhibited poor overall survival and progression‐free survival (PFS). The combination of high CD47 and CD133 expression was a reliable independent prognostic factor for both OS (HR = 1.940, 95% CI = 1.399‐2.690, P < 0.0001) and progression‐free survival (HR = 1.883, 95% CI = 1.384‐2.562, P < 0.0001). Notably, CD47+ CD133+ ESCC cells were observed to possess the characteristics of CSCs, and anti‐CD47 treatment veritably eliminated the CSCs pool. Conclusions The stemness index determined by the expression of CD47 and CD133 is a promising prognostic predictor, and CD47 is a potential therapeutic target for CSCs in ESCC patients.