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The reaction of substituted salicylaldehydes with α‐haloketones to obtain benzofuran‐2‐yl (Alkyl/aryl) ketones, which is a Dickman type aldol condensation product in base, solvent, and temperature environment, is called as Rap‐Stoermer reaction. In this study, a series of Benzofuran‐2‐yl (Alkyl/ aryl) ketones was synthesized by heating substituted salicylaldehydes and α‐haloketones under solvent‐free sealed (closed vessel) conditions by using triethyleamine (TEA) as a novel base catalyst in good to excellent yields (81–97 %) at 130 °C and the obtained results compared with the existing literature. The reaction conditions were optimized in terms of yield, time, base, solvent temperature, stoichiometric ratios, and synthesis environments (open or closed vessels). The optimized protocol offers promising advantages such as solvent‐free and clean reaction media, short reaction time, no byproducts, and appreciable high yields for the prospective studies. Characterization of the synthesized compounds was performed by using spectroscopic methods such as ATR‐FTIR, 1H‐NMR, 13C‐NMR and LC‐MS. [ABSTRACT FROM AUTHOR]

The intelligent design or development of dual‐functional catalysts using non‐precious metals especially for the oxygen evolution reaction (OER) in sustainable energy systems and degradation of organic pollutants is still a difficult and a significant challenge. Furthermore, the development of these catalysts is of great importance in terms of energy security and solution of the environmental problems. To meet these requirements, herein, we describe the synthesis of a Ni‐ion doped Birnessite@Cryptomelane (Ni2+/B@Cr) hybrid structure as a bifunctional efficient catalyst for the OER in neutral media and degradation of dye pollutants. The Ni2+/B@Cr catalyst exhibited a sharp onset potential at 390 mV (vs. RHE) and achieved a current density of 1 mA cm−2 at a low ƞ of 430 mV with a Tafel slope of ~96 mV dec−1. The results of electrochemical impedance spectroscopy (EIS) studies indicated that Ni intercalation into birnessite layer and heterostructure of the hybrid electrocatalyst Ni2+/B@Cr increased the conductivity by lowering the resistance of charge transfer (Rct = 4.82 Ω) and oxygen evolution processes (ROER = 4.13 Ω). The durability assay identified Ni2+/B@Cr as stable electrocatalyst with 10% loss of activity after long‐term stability tests (10 h, under 500‐mV overpotential). In addition, the Ni2+/B@Cr achieved high (86.67 s−1 g−1) and rapid (173 s) catalytic performance for the reduction of methylene blue (MB). Overall, this paper presents a low‐cost production strategy for the design of highly efficient bifunctional catalysts, offering boosted electrocatalytic and degradation performance for water oxidation and organic dye contamination, respectively. [ABSTRACT FROM AUTHOR]

The present paper reports a facile in situ synthesis strategy for the production of MnFe2O4@PDA‐Ag magnetically recyclable core–shell nanospheres by the deposition of silver nanoparticles (AgNPs) to the surface of MnFe2O4@PDA nanocomposites through the reduction of silver ions by the outer polydopamine (PDA) layer. The deposition of AgNPs over MnFe2O4@PDA was validated by scanning electron microscopy–energy‐dispersive X‐ray spectroscopy (SEM‐EDX), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and vibrating sample magnetometer (VSM) analysis. The catalytic reduction performance of the obtained MnFe2O4@PDA‐Ag nanospheres were tested over model organic dye pollutants (i.e., methylene blue [MB] and 4‐nitrophenol [4‐NP]) by sodium borohydride. Notably, the as‐prepared MnFe2O4@PDA‐Ag nanocatalyst exhibited significantly enhanced catalytic activity for the reduction of MB (296.52 s−1 g−1) and 4‐NP (92.02 s−1 g−1) compared with the other types of similar Ag‐ and PDA‐based catalytic systems in the recent literature. Moreover, the MnFe2O4@PDA‐Ag nanocatalyst showed excellent recyclability, ease of magnetic separation, and rapid and higher recovery ability with insignificant loss in their catalytic efficiencies even after several cyclic uses. The PDA coating on the surface of MnFe2O4 NPs allocates the surface functionalization for the building of novel catalyst systems. This work presents a simple and practicable for the synthesis of MnFe2O4@PDA‐Ag nanospheres that could have a great potential for the treatment of organic pollutants in wastewater and variety of applications in catalysis. [ABSTRACT FROM AUTHOR]

The present paper introduces a plant‐mediated green synthesis of highly stable MnFe2O4@EP@Ag magnetically recyclable nanocomposites (MRNCs) using Epilobium parviflorum (EP) tea extract as a coating material on MnFe2O4 nanoparticles (NPs) for the Ag immobilization. Fourier transform infrared spectroscopy‐attenuated total reflectance (ATR‐FTIR) studies confirmed the presence of the polyphenolics in EP extract, including tannic, gallic, and other derivatives, which can enhance the complexation properties with silver ions on MnFe2O4 NPs. Thus, the capacity and the surface properties of the resulting nanosorbent (MnFe2O4@EP) can also improve their ability to form magnetic nanocatalyts without using any additional chemicals, toxic or extra‐reducing agents. The transmission electron microscopy (TEM) verified the successful coating of EP extract on MnFe2O4 core as a 5 nm shell. X‐ray diffraction (XRD) patterns and scanning electron microscope/energy‐dispersive X‐ray spectroscopy (SEM–EDX) confirmed the presence of both MnFe2O4 and crystalline silver nanoparticles in the core‐shell structure of the MnFe2O4@EP@Ag MRNCs. The obtained MnFe2O4@EP@Ag MRNCs displayed high efficiency and catalytic activity for the reduction of various azo dyes like methyl orange (MO), methyl red (MR), congo red (CR), alizarin yellow (AY), nitro aromatic compound, 4‐Nitrophenol (4 NP), and a common tracer, rhodamine B (RhB). Results displayed that the MnFe2O4@EP@Ag MRNCs revealed higher catalytic activity with the normalized rate constant (knor) of 350.47 s−1 g−1 for RhB reduction. Furthermore, they were highly efficient in the reduction of other azo dyes and nitro compound in the order of MO (85.51 s−1 g−1) > CR (70.09 s−1 g−1) > 4 NP (62.15 s−1 g−1) > AY (54.67 s−1 g−1) > MR (46.73 s−1 g−1). In addition, the MnFe2O4@EP@Ag MRNCs exhibited an excellent unchanged recovery efficiency even after several cycles; therefore, they can be good potential candidates for the treatment of organic pollutants in wastewater and a wide range of applications in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Histological analysis of biological tissues by mechanical sectioning is significantly time‐consuming and error‐prone due to loss of important information during sample slicing. In the recent years, the development of tissue clearing methods overcame several of these limitations and allowed exploring intact biological specimens by rendering tissues transparent and subsequently imaging them by laser scanning fluorescence microscopy. In this review, we provide a guide for scientists who would like to perform a clearing protocol from scratch without any prior knowledge, with an emphasis on DISCO clearing protocols, which have been widely used not only due to their robustness, but also owing to their relatively straightforward application. We discuss diverse tissue‐clearing options and propose solutions for several possible pitfalls. Moreover, after surveying more than 30 researchers that employ tissue clearing techniques in their laboratories, we compiled the most frequently encountered issues and propose solutions. Overall, this review offers an informative and detailed guide through the growing literature of tissue clearing and can help with finding the easiest way for hands‐on implementation. [ABSTRACT FROM AUTHOR]

Glycosylated proteins modulate various important functions of organisms. To reveal the functions of glycoproteins, in‐depth characterization studies are necessary. Although mass spectrometry is a very efficient tool for glycoproteomic and glycomic studies, efficient sample preparation methods are required prior to analyses. In the study, poly(amidoamine) dendrimer‐coated magnetic nanoparticles were presented for the specific enrichment and fast purification of glycopeptides and glycans. The enrichment and purification performance of the developed method was evaluated both at the glycopeptide, and the glycan level using several standard glycoprotein digests and released glycan samples. The poly(amidoamine) dendrimer‐coated magnetic nanoparticles not only showed selective affinity (Immunoglobulin G/Bovine Serum Albumin, 1/10 by weight) to glycopeptides and released glycans but also good sensitivity (0.4 ng/µL for Immunoglobulin G) for glycoproteomic and glycomic applications. Thirty‐five glycopeptides of Immunoglobulin G were detected after enrichment with poly(amidoamine) dendrimer‐coated magnetic nanoparticles. In addition, 55 18O tagged deamidated glycopeptides belonging to human plasma glycoproteome were confirmed. Finally, fifty 2‐aminobenzoic acid, and 30 procainamide‐labelled human plasma N‐glycans released from human plasma glycoproteins were determined after purifications. The results indicate that the proposed enrichment and purification method using poly(amidoamine) dendrimer‐coated magnetic nanoparticles could be simply adjusted to sample preparation methods. [ABSTRACT FROM AUTHOR]

This study introduces a new straightforward strategy for screening the formation of catalytically active and monodisperse silver nanoparticles (AgNPs) using Epilobium parviflorum green tea extract and microwave technology. The method facilitates from multivariate statistical analysis for the optimization of the reaction conditions at which the produced AgNPs exhibit the best catalytic response for the model reduction reaction of 4‐nitrophenol (4‐NP). A five‐level two‐factor Central Composite (CCD) design of experiments (DOE) together with a response surface methodology (RSM) based desirability function approach was applied for the optimization of two variables, which are microwave exposure time and amount of silver nitrate, to obtain the desired monodisperse AgNPs displaying the best catalytic activity with the green and biogenic synthesis methods. The overall desirability of 82.2% for the measure of dispersity function of AgNPs (ψ) and the first‐order‐reaction rate constants (kapp) were obtained. The nanospheres with the TEM mean diameter of 19.10±2.06 nm were successfully synthesized in the optimized conditions: 15 min of microwave exposure time and 4 mL of AgNO3 (10 mM) at 100 °C with a laboratory‐grade microwave reactor and the formed nanoparticles were fully characterized. Verification experiments (ψ=3.546×105 and kapp=0.0293 s−1) confirmed the validity of the predicted model (ψ=3.567×105 and kapp=0.0291s−1) (p<0.05). [ABSTRACT FROM AUTHOR]

Contamination through Hg2+ ions in natural spring waters leads to a major destruction in human health and the universal ecosystem. Therefore, development of rapid, simple and cost‐effective methods for the specific and high sensitive determination of Hg2+ is of great importance. Among these methods, silver nanoparticles (Ag NPs) are used for the effective colorimetric detection of metal ions facilitating from the changes in the surface plasmon resonance (SPR) band. In this study, we have synthesized dendrimer‐encapsulated Ag NPs (Ag DENPs) by using Tris(2‐aminoethyl)amine (TREN) cored and amine‐terminated generation‐4 poly(amido amine) dendrimer (PAMAM), T4.NH2, as a novel template. The synthesized Ag DENPs were characterized by UV‐Vis, XRD, TEM and further used for the colorimetric and quantitative determination of Hg2+ ions. The developed Ag DENP sensor was tested against common present cations, Co2+, Cu2+, Cd2+, Pb2+, Ni2+ Zn2+, Ba2+, Ca2+, Al3+, in the environment and found to be specific only for Hg2+ ions. Furthermore, limit of detection (LOD) for Hg2+ was found to be 1.18 ppb (5.88 nM). Results revealed that the proposed method can be successfully used with a good sensitivity and selectivity to determine mercury (II) ions in various water samples. [ABSTRACT FROM AUTHOR]

Carbonic anhydrase XII (CAXII) is a membrane‐tethered ectoenzyme involved in intracellular pH regulation and overexpressed across various types of human cancer. Because CAXII inhibition shows antitumor activity in vitro, it is thought that the enzyme is mandatory for maximum tumor growth, above all under hypoxic conditions. Recently, it has been shown that CAXII is co‐expressed along with the P‐glycoprotein (P‐GP) on many tumor cells and that both proteins physically interact. Of interest, blocking CAXII activity also decreases P‐GP activity in cancer cells both in vitro and in vivo. Previously, we have reported on the development of a monoclonal antibody, termed 6A10, which specifically and efficiently blocks human CAXII activity. Here, we demonstrate that 6A10 also indirectly reduces P‐GP activity in CAXII/P‐GP double‐positive chemoresistant cancer cells, resulting in enhanced chemosensitivity as revealed by enhanced accumulation of anthracyclines and increased cell death in vitro. Even more important, we show that mice carrying human triple‐negative breast cancer xenografts co‐treated with doxorubicin (DOX) and 6A10 show a significantly reduced number of metastases. Collectively, our data provide evidence that the inhibition of CAXII with 6A10 is an attractive way to reduce chemoresistance of cancer cells and to interfere with the metastatic process in a clinical setting. [ABSTRACT FROM AUTHOR]