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Ti 3 C 2 T x is a two-dimensional (2D) material belonging to the MXenes family. It has a unique combination of functional features that make it appropriate for a wide range of fascinating applications, including supercapacitors, batteries, strain sensors, photocatalysis, and more. In this study, we report a synthesis of Ti 3 C 2 -TiO 2 nanocomposites with tight interfacial contact that has been successfully fabricated by in situ development of TiO 2 nanoparticles (NPs) on the surface of Ti 3 C 2 T x nanosheets (NSs) via a simple and cost-effective hydrothermal process. The catalysts are well characterized by various sophisticated techniques, including X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), Brunauer-Emmett-Teller (BET), CHI660E electrochemical workstation, and HRTEM. The photocatalytic performance of pure Ti 3 C 2 Tx, Ti 3 C 2 -TiO 2 (MT1), and Ti 3 C 2 -TiO 2 (MT5) nanocomposites was evaluated by highly selective photo-oxidation of biomass-derived furfuryl alcohol (FA), cinnamyl alcohol, vanillin alcohol, and various aromatic alcohols to the corresponding aldehyde with >99% selectivity for all the alcohol substrates under visible light (385–740 nm). Photocatalytic oxidation results revealed that Ti 3 C 2 -TiO 2 (MT5) has superior photocatalytic activity than Ti 3 C 2 -TiO 2 (MT1) and pure Ti 3 C 2 T x NSs. The exceptional photocatalytic activity was attributed to the composite's unique morphology and characteristics. [Display omitted] • MXene generated TiO 2 (in-situ derived TiO 2 from MXene) was synthesized using simple and green hydrothermal process. • Oxidation of biomass derived alcohols and other aromatic alcohols to corresponding aldehydes with >99 % selectivity. • Conversion, selectivity and yield of furfural, and cinnamaldehyde is >99 %. • MXene can operate as a co-catalyst in the metal-semiconductor contact, which causes an increase in the flow of electrons. [ABSTRACT FROM AUTHOR]

Abstract Waterborne polyurethane (WPU) has been broadly used as adhesive and coating materials in many applications. In this work, the graphene oxide-silica (GOSI) nanocomposites, used as nanofillers in the WPU matrix, were produced by functionalizing graphene oxide with epoxy groups and nanosilica with amine groups using silane terminated coupling agents. The nanocomposite surface structures were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The polymer nanocomposite films show the excellent improvement in the mechanical and thermal properties. In the fractured surface study of the composite films by SEM, it was observed that the agglomeration of GO appears while the GOSI is uniformly distributed in the WPU matrix. Furthermore, the WPU/GOSI have regained the maximum tensile strength properties after two weeks of hydrolysis. The GOSI nanocomposites have enhanced interfacial crosslinking with the WPU matrix which is the prime reason for such development in the mechanical properties. The screen printing method was illustrated to cast the thin and transparent layer WPU nanocomposites on the leather surfaces. The WPU/GOSI coatings exhibit outstanding tear resistance, surface adhesiveness, and abrasion resistance properties. This approach of using GOSI composites as nanofiller in the polymer matrix may pave a novel path for surface coating strategies. Graphical abstract Image 1 Highlights • The WPU/GOSI nanocomposites were prepared by epoxy functionalized GO and amine functionalized nanosilica, and then by physical mixing with WPU. • Comparing to the neat WPU films, the WPU/GOSI films exhibit significant improvement in mechanical and thermal properties. • The hydrolysis resistance and water resistance capability of WPU were also dramatically enhanced by introducing the GOSI nanocomposites into WPU matrix. • The WPU/GOSI nanocomposite coatings on leather surfaces show excellent adhesion, flexibility, and abrasion resistance properties. [ABSTRACT FROM AUTHOR]

MK2 (p38 MAPK -activated protein kinase 2) is essential for tumor necrosis factor (TNF) biosynthesis, mainly operating by post-transcriptional regulation. Deletion of the gene encoding MK2 strongly reduced serum TNF and protected against endotoxic shock, demonstrating the positive role of p38 MAPK /MK2 in TNF signaling at the level of ligand expression. Recent evidence indicates that MK2 directly phosphorylates the TNF receptor interactor RIPK1 and suppresses its activity, thereby limiting TNF-mediated apoptosis and necroptosis – pointing to a more complex, double-edged role of MK2 in TNF signaling. In addition, novel MK2 substrates have emerged in the DNA damage response, autophagy, and obesity, making MK2 a multifunctional kinase at the crossroads of stress response and cell death. We therefore propose a more general role of p38 MAPK /MK2 signaling in the timely coordinated onset and resolution of inflammation and beyond. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer is an aggressive form of breast cancer with few therapeutic options if it recurs after adjuvant chemotherapy. RNA interference could be an alternative therapy for metastatic breast cancer, where small interfering RNA (siRNA) can silence the expression of aberrant genes critical for growth and migration of malignant cells. Here, we formulated a siRNA delivery system using lipid-substituted polyethylenimine (PEI) and hyaluronic acid (HA), and characterized the size, ζ-potential and cellular uptake of the nanoparticulate delivery system. Higher cellular uptake of siRNA by the tailored PEI/HA formulation suggested better interaction of complexes with breast cancer cells due to improved physicochemical characteristics of carrier and HA-binding CD44 receptors. The siRNAs against specific phosphatases that inhibited migration of MDA-MB-231 cells were then identified using library screen against 267 protein-tyrosine phosphatases, and siRNAs to inhibit cell migration were further validated. We then assessed the combinational delivery of a siRNA against CDC20 to decrease cell growth and a siRNA against several phosphatases shown to decrease migration of breast cancer cells. Combinational siRNA therapy against CDC20 and identified phosphatases PPP1R7, PTPN1, PTPN22, LHPP, PPP1R12A and DUPD1 successfully inhibited cell growth and migration, respectively, without interfering the functional effect of the co-delivered siRNA. The identified phosphatases could serve as potential targets to inhibit migration of highly aggressive metastatic breast cancer cells. Combinational siRNA delivery against cell cycle and phosphatases could be a promising strategy to inhibit both growth and migration of metastatic breast cancer cells, and potentially other types of metastatic cancer. Statement of Significance The manuscript investigated the efficacy of a tailored polymeric siRNA delivery system formulation as well as combinational siRNA therapy in metastatic breast cancer cells to inhibit malignant cell growth and migration. The siRNA delivery was undertaken by non-viral means with PEI/HA. We identified six phosphatases that could be critical targets to inhibit migration of highly aggressive metastatic breast cancer cells. We further report on specifically targeting cell cycle and phosphatase proteins to decrease both malignant cell growth and migration simultaneously. Clinical gene therapy against metastatic breast cancer with effective and safe delivery systems is urgently needed to realize the potential of molecular medicine in this deadly disease and our studies in this manuscript is intended to facilitate this endeavor. [ABSTRACT FROM AUTHOR]

Synthesis of novel C 2 -symmetric 1,2- 1,3- and 1,4- bis-sulfinamides and their use as effective ligands in rhodium (I) catalyzed asymmetric conjugate addition of arylboronic acids to cyclohexenone and cyclopentenones is described. C 2 -symmetry as well as chirality at the sulfur center in the ligand is crucial for the high enantioselectivity in the 1,4-addition reaction. It was also observed that the conjugate addition proceeded with good selectivity with Wilkinson's catalyst as the rhodium source. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we examined the evolutionary trajectories and the common ancestor of medaka rbp genes by comparing them to the well-studied rbp/RBP genes from zebrafish and other vertebrates. We describe here gene structure, sequence identity, phylogenetic analysis and conserved gene synteny of medaka rbp genes and their putative proteins as well as the tissue-specific distribution of rbp transcripts in adult medaka and zebrafish. Medaka rbp genes consist of four exons separated by three introns that encode putative polypeptides of 134–138 amino acids, a genomic organization characteristic of rbp genes. Medaka Rbp sequences share highest sequence identity and similarity with their orthologs in vertebrates, and form a distinct clade with them in phylogenetic analysis. Conserved gene synteny was evident among medaka, zebrafish and human rbp/RBP genes, which provides compelling evidence that the medaka rbp1, rbp2a, rbp2b, rbp5, rbp7a and rbp7b genes arose from a common ancestor of vertebrates. Moreover, the duplicated rbp2 and rbp7 genes most likely exist owing to a whole-genome duplication (WGD) event specific to the teleost fish lineage. Selection pressure and the nonparametric relative rate test of the medaka and zebrafish duplicated rbp2 and rbp7 genes suggest that these duplicated genes are subjected to purifying selection and one paralog might have evolved at an accelerated rate compared to its sister duplicate since the WGD. The steady-state levels of medaka and zebrafish rbp1, rbp2a, rbp2b and rbp5 transcripts in various tissues suggest that medaka rbp1, rbp2a and rbp2b genes have retained the regulatory elements of an ancestral RBP1 and RBP2 genes, and the medaka rbp5 gene has acquired new function. Furthermore, the tissue-specific regulations of rbp7a and rbp7b genes have diverged markedly in medaka and zebrafish since the teleost-specific WGD. [Copyright &y& Elsevier]

Abstract: Here we report the genomic organization of duplicated cellular retinoic acid-binding protein genes, crabp1 and crabp2, in medaka (Japanese ricefish; Oryzias latipes), the phylogenetic relationship of medaka Crabp1a, Crabp1b, Crabp2a and Crabp2b with other Crabp/CRABP sequences from teleosts/tetrapods, and the tissue-specific distribution of crabp1a, crabp1b, crabp2a, and crabp2b transcripts in adult medaka. The duplicated medaka crabp1 and crabp2 genes contain four exons separated by three introns, which encode polypeptides of 137 and 142 amino acids, respectively. Sequence alignment revealed that medaka Crabp sequences share highest sequence identity and similarity with their orthologs from vertebrates. Phylogenetic analysis confirmed the orthology of the medaka Crabps as they form a distinct clade with their orthologous polypeptides from vertebrates. Conserved gene synteny was evident between the duplicated crabp1 and crabp2 genes from medaka, and CRABP1 and CRABP2 genes from human, which provides compelling evidence that the identified duplicated crabp1 and crabp2 genes from medaka most likely arose owing to teleost-specific whole-genome duplication. The tissue-specific distribution of zebrafish (Danio rerio) and medaka crabp1a, crabp1b, crabp2a, and crabp2b gene transcripts suggests acquisition of new function by these genes in medaka, which may explain potential evolutionary processes that led to the retention of sister duplicates of crabp1 and crabp2 genes in the medaka genome. [Copyright &y& Elsevier]

Abstract: We describe the evolutionary diversification of the duplicated ileal fatty acid-binding protein genes (fabp6a and fabp6b) from Japanese ricefish (Oryzias latipes; medaka) and three-spined stickleback (Gasterosteus aculeatus). The fabp6a and fabp6b genes from medaka and three-spined stickleback encode polypeptides of 125–127 amino acids, which share highest sequence identity with their orthologs in teleost fishes and tetrapods. All Fabp6a and Fabp6b from different species cluster together in a distinct clade in phylogenetic analysis and the topology of the tree suggests that fabp6a and fabp6b from medaka and three-spined stickleback are most likely duplicated genes of an ancestral FABP6 owing to teleost-specific whole-genome duplication. However, the topology of an alternate phylogenetic tree revealed that the duplication of the ancestral FABP6 that gave rise to the extant fabp6a and fabp6b possibly occurred before the divergence of tetrapods and fishes. Conserved gene synteny was evident between the teleost fabp6a and fabp6b genes and the human FABP6 gene. The tissue-specific distribution of fabp6a transcripts suggests the retention of ancestral function(s) of the fabp6a gene in medaka and three-spined stickleback with acquisition of new function(s) in different tissues. However, the tissue-specific regulation of the fabp6b gene has diverged markedly in medaka and three-spined stickleback since the duplication of the fabp6 gene. [Copyright &y& Elsevier]

Abstract: Injected therapeutics, such as cells or biological molecules, may have enhanced efficiency when delivered within a scaffold carrier. Here, we describe a dual-component Dock-and-Lock (DnL) self-assembly mechanism that can be used to construct shear-thinning, self-healing, and injectable hydrogels. One component is derived from the RIIα subunit of cAMP-dependent kinase A and is engineered as a telechelic protein with end groups that dimerize (docking step). The second component is derived from the anchoring domain of A-kinase anchoring protein (AD) and is attached to multi-arm crosslinker polymers and binds to the docked proteins (locking step). When mixed, these two DnL components form robust physical hydrogels instantaneously and under physiological conditions. Mechanical properties and erosion rates of DnL gels can be tuned through the AD peptide sequence, the concentration and ratio of each component, and the number of peptides on the cross-linking polymer. DnL gels immediately self-recover after deformation, are resistant to yield at strains as high as 400%, and completely self-heal irrespective of prior mechanical disruption. Mesenchymal stem cells mixed in DnL gels and injected through a fine needle remain highly viable (>90%) during the encapsulation and delivery process, and encapsulated large molecules are released with profiles that correspond to gel erosion. Thus, we have used molecular engineering strategies to develop cytocompatible and injectable hydrogels that have the potential to support cell and drug therapies. [Copyright &y& Elsevier]

Abstract: Downstream of mitogen-activated protein kinases (MAPKs), three structurally related MAPK-activated protein kinases (MAPKAPKs or MKs) – MK2, MK3 and MK5 – signal to diverse cellular targets. Although there is no known common function for all three MKs, MK2 and MK3 are mainly involved in regulation of gene expression at the post-transcriptional level and are implicated in inflammation and cancer. MK2 and MK3 are phosphorylated and activated by p38MAPKα,β and, in turn phosphorylate various substrates involved in diverse cellular processes. In addition to forwarding of the p38-signal by MK2/3, protein complex formation between MK2/3 and p38 mutually stabilizes these enzymes and affects p38MAPK signaling in general. Among the substrates of MK2/3, there are mRNA-AU-rich-element (ARE)-binding proteins, such as tristetraprolin (TTP) and hnRNP A0, which regulate mRNA stability and translation in a phosphorylation-dependent manner. Phosphorylation by MK2 stabilizes TTP, releases ARE-containing mRNAs, such as TNF-mRNA, from default translational repression and inhibits their nucleolytic degradation. Here we demonstrate that MK2/3 also contribute to the de novo synthesis of TTP. Whether this contribution proceeds via transcription factors directly targeted by MK2/3 or via chromatin remodeling by the reported binding of MK2/3 to the polycomb repressive complex is still open. A model is proposed, which demonstrates how this new function of transcriptional activation of TTP by MK2/3 cooperates with the role of MK2/3 in post-transcriptional gene expression to limit the inflammatory response. [ABSTRACT FROM AUTHOR]

Summary: Micronuclei (MN) are extensively used as an indicator of chromosomal damage and early biomarker of cancer risk. The genetic host factors are known to influence the level of chromosomal alterations consequently affecting MN frequencies. Hence, in the present study, we investigated the extent of chromosomal damage by analyzing micronucleated cell (MNC) frequency in exfoliated buccal epithelial cells (BEC) and its possible relationship with genetic polymorphisms in patients with oral leukoplakia (OL). The study group comprised of habit-free (NHC, n =39), habit controls (HC, n =62) and OL patients (n =66). Micronucleus assay was carried out to determine the MNC frequency and the genotyping was performed by PCR–RFLP for metabolizing (CYP1A1, GSTM1, GSTT1, GSTP1) and DNA repair (hOGG1, XRCC1, XPD) genes. The correlation between MNC frequency and genetic polymorphisms was analyzed. We found significant increase in overall MNC frequency in OL patients as compared to habit-matched controls (p =0.01). The higher proportion of multiple micronucleated cells (>5 MN per cell) indicate increased DNA damage in the buccal mucosa of OL patients than the controls (p =0.004). The polymorphic alleles of XPD751 and hOGG1 showed significant association with total MNC frequency in OLs (p =0.034 and p =0.03 respectively). In conclusion, the extent of chromosomal damage in target tissues is higher in patients with OL. MNC frequency in combination with genetic polymorphisms in DNA repair genes may serve as better predicator of risk. [ABSTRACT FROM AUTHOR]

Abstract: N-Benzyloxycarbonylation of amines was carried out in aqueous micellar media. Aliphatic (open and cyclic), aromatic and heteroaromatic amines react with Cbz-Cl to give excellent yields of products. The reactions were carried out in water and at room temperature. [Copyright &y& Elsevier]

Abstract: The efficiency of phosphated zirconia, a solid acid catalyst for the synthesis of bis(indolyl)methanes (BIM) was determined. The reaction was carried out under mild and solvent free conditions and the acid catalyst could be easily separated and reused. The characterization of the catalysts was carried out using XRD and FT-IR and the characterized phosphated zirconia catalysts were used for synthesis. Effect of various parameters such as calcination temperature, phosphoric acid concentration, solvents, reaction temperature and catalyst loading has been studied. [Copyright &y& Elsevier]

Abstract: Cross-aldol condensation of aromatic aldehydes with cyclic ketones in a micellar medium afforded α,α′-bis (substituted benzylidene) cycloalkanones in high yields. Knoevenagel condensation carried out in micellar media is observed to be faster than that in the aqueous solution. The present method is operationally simple and the use of water as the reaction medium makes the process environmentally benign. [Copyright &y& Elsevier]

Abstract: A simple, facile, and chemoselective N-benzyloxycarbonylation of amines using silica–sulfuric acid that proceeds under solvent-free conditions at room temperature has been achieved. These reactions are applicable to a wide variety of primary (aliphatic and cyclic) secondary amines, amino alcohols, and heterocyclic amines. [Copyright &y& Elsevier]