Altered DNA Binding and Amplification of Human Breast Cancer Suppressor Gene BRCA1 Induced by a Novel Antitumor Compound, [Ru(��6-p-phenylethacrynate)Cl2(pta)]

The ruthenium-based complex [Ru(η⁶-p-phenylethacrynate)Cl₂(pta)] (pta = 1,3,5-triaza-7-phosphatricyclo-[3.3.1.1]decane), termed ethaRAPTA, is an interesting antitumor compound. The elucidation of the molecular mechanism of drug activity is central to the drug development program. To this end, we have characterized the ethaRAPTA interaction with DNA, including probing the sequence specific modified DNA structural stability and DNA amplification using the breast cancer suppressor gene 1 (BRCA1) of human breast and colon adenocarcinoma cell lines as models. The preference of ethaRAPTA base binding is in the order A > G > T > C. Once modified, the ethaRAPTA-induced BRCA1 structure has higher thermal stability than the modified equivalents of its related compound, RAPTA-C. EthaRAPTA exhibits a higher efficiency than RAPTA-C in inhibiting BRCA1 amplification. With respect to both compounds, the inhibition of BRCA1 amplification is more effective in an isolated system than in cell lines. These data provide evidence that will help to understand the process of elucidating the pathways involved in the response induced by ethaRAPTA.     

Modeling and analysis of rainfall processes in the context of climate change for Mekong,Chi, and Mun River Basins (Thailand)

This paper provides a detailed characterization of the observed daily rainfall series available for the Mekong, Chi, and Mun River Basins in the context of climate change; and describes the linkage between climate simulations given by Global Circulation Models (GCMs) and the local rainfall characteristics using the popular Statistical Downscaling Model (SDSM). Observed daily rainfall records at 11 stations in the study area for the 1961–2007 period were considered. Results of characterizing the available rainfall data for the 1961–1990 and 1991–2007 periods show different trends of rainfall characteristics for different locations in the study area. However, a consistent increase in the annual maximum number of consecutive dry days (CDD) was observed in the Chi catchment area, the eastern part of the Mun watershed, and the western portion of the Mekong River Basin. In addition, decrease in the annual maximum daily rainfall (AMDR) was found in most locations of the study area, except for the central part of the Chi and Mun River Basins. Moreover, it has been shown in this paper that the SDSM could adequately describe the basic statistical and physical characteristics of the observed rainfall processes for the calibration (1961–1975) and validation (1976–1990) periods. This statistical downscaling method was then used to project future rainfall characteristics for the 1961–2099 period using the climate simulations given by the UK HadCM3 (HadCM3) model under A2 and B2 scenarios (HadCM3A2 and HadCM3B2), and by the Canadian GCM3 (CGCM3) model under A2 and A1B scenarios (CGCM3A2 and CGCM3A1B). In general, the projected trends of rainfall characteristics by both HadCM3 and CGCM3 were found to be consistent with the observed historical trends. However, there was a large difference in the projection results given by these two models. This would indicate the presence of high uncertainty in climate simulations provided by different GCMs. In addition, the climate change impacts on the flood and drought problems in the study area were shown using the CDD and AMDR indices of 100-year return period.     

Gut microbiota modulation and immune boosting properties of prebiotic dragon fruit oligosaccharides

This is the first report of the evaluation of suitability for consumption of dragon fruit oligosaccharide (DFO) and its efficacy on gut microbiota modulation and in boosting the gut immune response in rats. The DFO produced significantly increased faecal bifidobacteria and lactobacilli but decreased bacteroides and clostridia. The DFO also showed immune-response boosting properties by significantly increasing the plasma immunoglobulin A and G concentrations. In addition, it was confirmed by blood chemistry analysis and histology of the colon of the rats that DFO is suitable for the consumption. These results suggest that DFO is a potentially novel source of prebiotic ingredients with probiotic-stimulation and immune boosting properties.     

Bioactive components,antioxidative and anti-inflammatory properties (on RAW 264.7 macrophage cells) of soaked and germinated purple rice extracts

The bioactive components, antioxidative properties and phenolic profile of Thai purple rice after 24 h soaking and 36 h germination periods were investigated. Anti-inflammatory properties of the rice extracts were also evaluated on macrophage cells, stimulated with Lipopolysaccharide. These conditions significantly increased the bioactive components and antioxidative properties. Total anthocyanin contents, total carotenoid contents and gamma-aminobutyric acid were increased more than twofold in the soaked sample. Protocatechuic, caffeic, p-coumaric, ferullic, rutin trihydrate, catechin and Trans-cinnamic acids were detected in the extracts. Gallic acid was only identified after soaking and germination. All the extracts led to cell proliferation and inhibited nitric oxide (NO) production. Twenty-four hour soaking exhibited highest bioactive compounds, antioxidative properties and showed greater NO inhibitory effects with IC₅₀ of 234.00 ± 0.01 μg mL⁻¹. In addition to established information on germination, soaking greatly improved the bioactive components and anti-inflammatory properties of the rice variety.