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Benzo[a]pyrene-modified oligonucleotides were developed for the detection of RNAs with a point mutation. The probes produced two distinct fluorescence signals in response to single nucleotide differences in the RNA sequences, allowing for discrimination between the matched and single base mismatched RNA sequences in colorimetric and ratiometric manners. [ABSTRACT FROM AUTHOR]

We developed a centromere-associated protein E (CENP-E) inhibitor employing trans to cis photoisomerization with 405 nm visible light illumination and fast thermal relaxation. This photoswitching characteristic of the inhibitor enabled selective blockage or release of the motion of particular chromosomes within a single mitotic cell. Using this technique, we successfully demonstrated targeted chromosome gain and loss in daughter cells by introducing asymmetric chromosome segregation. [ABSTRACT FROM AUTHOR]

Freezing impinged water droplets on glass surfaces cause serious problems such as reduced visibility of traffic lights and surveillance cameras. Droplets in the air associated with these issues are often at subzero temperatures. However, experimental results on the freezing of precooled impinged droplets are limited. In this study, we measured the freezing of precooled and impinged water droplets on cold glass surfaces. Two types of lattice-patterned microscale grooves were formed on glass surfaces to reduce the contact area of droplets and growth of frosts, which contributed to droplet freezing. In addition, the surfaces were coated with a silane coupling agent to further reduce the contact area. We analyzed the images of droplets captured using a high-speed video camera. The results of the linear relationships between the frozen droplet height, freezing front velocity, and freezing time (for the impinged droplets) indicated that the grooves and coating were effective in retarding the freezing of impinged droplets. This retardation was more evident for frost-free glass surfaces, and it was less evident for precooled droplets. Moreover, a simple heat transfer analysis was conducted to effectively estimate the overall heat flux and freezing front velocity. The sublimation of frost (adjacent to the impinged droplets) and supercool elimination of the precooled droplets significantly contributed to the heat flux and caused an increase in the freezing front velocity. [ABSTRACT FROM AUTHOR]

The present study investigated the therapeutic effects of the curcumin derivative 3-[(1E)-2-(1H-indol-6-yl)ethenyl]-5-[(1E)-2-[2-methoxy-4-(2-pyridylmethoxy)phenyl]ethenyl]-1H-pyrazole (GT863) in amyotrophic lateral sclerosis (ALS). The inhibitory effect of GT863 on superoxide dismutase 1 (SOD1) aggregation was evaluated in cell-free assays. GT863 interfered with the conformational changes of the SOD1 protein and later, oligomeric aggregation. Furthermore, its antioxidant, anti-inflammatory, and neuroprotective effects were evaluated in cell-free and cultured cell assays. GT863 inhibited H2O2− and glutamate-induced cytotoxicity and activated an antioxidant responsive element pathway. Additionally, in vivo effects of GT863 in the ALS mice model were evaluated by its oral administration to H46R mutant SOD1 transgenic mice. Rotarod test showed that GT863 administration significantly slowed the progression of motor dysfunction in the mice. In addition, GT863 substantially reduced highly-aggregated SOD1, further preserving large neurons in the spinal cord of GT863-treated mice. Collectively, these results indicated that GT863 could be a viable therapeutic agent with multiple vital actions for the treatment of ALS. [ABSTRACT FROM AUTHOR]

Nucleic acids in body fluids, such as circulating cell-free nucleic acids, viral DNA, and RNA have received much attention for their great potential as biomarkers in liquid biopsies of serious diseases. Although quantitative polymerase chain reaction (qPCR) has been traditionally used as a laboratory-based assay for measuring nucleic acids, there is a strong demand for techniques to qualitatively, rapidly, and simply measure the extremely low-abundance nucleic acids in order to realize the nucleic acid-based liquid biopsies. With this aim in mind, we developed a simple and highly sensitive sandwich-type assay for nucleic acids using a combination of surface-enhanced Raman scattering (SERS), which enhances Raman scattering by 108– to 1010–fold, and bioorthogonal Raman tags, which generate signals in the biologically silent region (1800–2800 cm−1). Using gold nanorods having approximately 240 strands of oligonucleotides and 4-cyano-N-(2-mercaptoethyl)benzamide (4CMB) as the bioorthogonal Raman tag, we successfully detected target nucleic acids in a sequence-selective manner. [ABSTRACT FROM AUTHOR]

Amyloid fibrils are supramolecular polymers with β-sheet-rich structures formed by polymerization of protein/peptide with intermolecular interaction. Amyloid fibrils have been miscast as toxic villains since they have historically been studied as pathogens associated with serious diseases, including Alzheimer's and Parkinson's disease. However, recent studies on their toxicity and formation mechanism and discovery of their functionality in nature correct the misconception and strongly facilitate the possible use of β-sheet-forming peptides in designing novel nanomaterials. Self-assembly based on β-sheet-forming peptides can provide highly ordered nanostructures under certain conditions. Therefore, ingenious design of the building block peptides allows the construction of nano-assemblies, which contain large quantities of bio-functional molecules, including drugs and bioactive peptides, and exhibit unique properties, such as assembly or disassembly in response to external stimulus or specific molecules. These properties provide a novel strategy for the creation of innovative nanomaterials, especially for biomedical applications. Here, we describe recent progress in the biomedical application of fibrous assemblies based on β-sheet-forming peptides, such as the suppression of aberrant protein aggregation, controlled release, tissue engineering and other applications. This review focuses not only on the function of the nanofibrous assemblies but also on the functions of component molecules, namely amyloidogenic peptides. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]