10 research outputs found
RNA/DNA hybrid duplexes with identical nearest-neighbor base-pairs have identical stability
AbstractEnergetic behaviors of eight pairs of RNA/DNA hybrid duplexes with identical nearest neighbors have been investigated by UV melting analysis. In the pairs with identical nearest-neighbor pairs, the melting curve traces at the same strand concentration were very similar. The average difference in stabilization energy of these pairs was 4%, which was about expected within experimental error. These results indicate that the nearest-neighbor model is valid for predicting the stability of RNA/DNA hybrid duplexes as well as RNA/RNA and DNA/DNA duplexes
Two times lowering of lake water at around 48 and 38 ka, caused by possible earthquakes, recorded in the Paleo-Kathmandu lake, central Nepal Himalaya
Sedimentary facies and micro-fossil analyses, and AMS[14]C dating were performed in order to reveal the water-level fall events and draining process of the lake (Paleo-Kathmandu Lake) that existed in the past in the Central Nepal Himalaya. The sedimentary facies change from the lacustrine Kalimati Formation to the deltaic Sunakothi Formation in the southern and central Kathmandu basin, and the abrupt and prominent increase of phytoliths Bambusoideae and Pediastrum, and contemporaneous decrease of sponge spicule and charcoal grains around 48 and 38 ka support the lowering of water level at these times. According to the pollen analysis, both events occurred under rather warm and wet climate, thus supporting that they were triggered by tectonic cause and not by climate change. The first event might be linked to a possible occurrence of a large earthquake with an epicenter in the vicinity of the Paleo-Kathmandu Lake. The occurrence of a mega landslide in Langtang area close to the north of the Kathmandu Valley producing pseudotachylite dated at 51 ± 13 ka could be linked to this earthquake. Finally, the water was completely drained out from the remnant lake at the central part of the Kathmandu basin by ca.12 ka
A novel aqueous extract from rice fermented with Aspergillus oryzae and Saccharomyces cerevisiae possesses an anti-influenza A virus activity.
Human influenza virus infections occur annually worldwide and are associated with high morbidity and mortality. Hence, development of novel anti-influenza drugs is urgently required. Rice Power® extract developed by the Yushin Brewer Co. Ltd. is a novel aqueous extract of rice obtained via saccharization and fermentation with various microorganisms, such as Aspergillus oryzae, yeast [such as Saccharomyces cerevisiae], and lactic acid bacteria, possessing various biological and pharmacological properties. In our previous experimental screening with thirty types of Rice Power® extracts, we observed that the 30th Rice Power® (Y30) extract promoted the survival of influenza A virus-infected Madin-Darby canine kidney (MDCK) cells. Therefore, to identify compounds for the development of novel anti-influenza drugs, we aimed to investigate whether the Y30 extract exhibits anti-influenza A virus activity. In the present study, we demonstrated that the Y30 extract strongly promoted the survival of influenza A H1N1 Puerto Rico 8/34 (A/PR/8/34), California 7/09, or H3N2 Aichi 2/68 (A/Aichi/2/68) viruses-infected MDCK cells and inhibited A/PR/8/34 or A/Aichi/2/68 viruses infection and growth in the co-treatment and pre-infection experiments. The pre-treatment of Y30 extract on MDCK cells did not induce anti-influenza activity in the cell. The Y30 extract did not significantly affect influenza A virus hemagglutination, and neuraminidase and RNA-dependent RNA polymerase activities. Interestingly, the electron microscopy experiment revealed that the Y30 extract disrupts the integrity of influenza A virus particles by permeabilizing the viral membrane envelope, suggesting that Y30 extract has a direct virucidal effect against influenza A virus. Furthermore, we observed that compared to the ethyl acetate (EtOAc) extract, the water extract of Y30 extract considerably promoted the survival of cells infected with A/PR/8/34 virus. These results indicated that more anti-influenza components were present in the water extract of Y30 extract than in the EtOAc extract. Our results highlight the potential of a rice extract fermented with A. oryzae and S. cerevisiae as an anti-influenza medicine and a drug source for the development of anti-influenza compounds