Flavonol glycosides and novel iridoid glycoside from the leaves of Morinda citrifolia

One new iridoid glycoside and five known flavonol glycosides have been isolated from the leaves of Morinda citrifolia. The new iridoid exists as an epimeric mixture in solution. Complete assignments of the proton and carbon chemical shifts for the individual epimers were accomplished on the basis of high-resolution 1D and 2D NMR data. Their antioxidative activities were measured. All of these compounds showed DPPH free radical scavenging activity at the concentration of 30 microM.     

Soil Formation in the Taiga–Steppe Ecotone of the Selenga Mountains,Western Transbaikal Region

Eurasian Soil Science - A new view on the genesis and properties of soils in landscapes of the taiga–steppe ecotone in the Selenga Mountains of western Transbaikalia is suggested with due...     

Vital Stain in Milk-Based Medium to Evaluate Sperm Quality

Assisted reproductive technology plays a key role in bovine reproduction in herds. Different media, including the milk-based medium, are used for bull semen cryopreservation. The objective of the survey was to develop a method for assessing sperm motility in frozen-thawed semen of the bull sires with the use of the vital stains added to the milk-based medium. It has been proven that vital staining with the use of Hoechst 33342 Dye in the milk-based medium is the most efficient in order to assess the motility of the frozen-thawed semen collected from the bull sires. The current method for semen detection can yield 100% accurate results.     

Pterostilbene induces apoptosis and cell cycle arrest in human gastric carcinoma cells

Pterostilbene, an active constituent of blueberries, is known to possess anti-inflammatory activity and also induces apoptosis in various types of cancer cells. Here, the effects of pterostilbene on cell viability in human gastric carcinoma AGS cells were investigated. This study demonstrated that pterostilbene was able to inhibit cell proliferation and induce apoptosis in a concentration- and time-dependent manner. Pterostilbene-induced cell death was characterized with changes in nuclear morphology, DNA fragmentation, and cell morphology. The molecular mechanism of pterostilbene-induced apoptosis was also investigated. The results show the caspase-2, -3, -8, and -9 are all activated by pterostilbene, together with cleavage of the downstream caspase-3 target DNA fragmentation factor (DFF-45) and poly(ADP-riobse) polymerase. Moreover, the results indicate that the Bcl-family of proteins, the mitochondrial pathway, and activation of the caspase cascade are responsible for pterostilbene-induced apoptosis. Pterostilbene markedly enhanced the expression of growth arrest DNA damage-inducible gene 45 and 153 (GADD45 and GADD153) in a time-dependent manner. Flow cytometric analysis indicated that pterostilbene blocked cell cycle progression at G1 phase in a dose- and time-dependent manner. Pterostilbene increased the p53, p21, p27, and p16 proteins and decreased levels of cyclin A, cyclin E, cyclin-dependent kinase 2 (Cdk2), Cdk4, and Cdk6, but the expression of cyclin D1 was not affected. Over a 24 h exposure to pterostilbene, the degree of phosphorylation of Rb was decreased after 6 h. In summary, pterostilbene induced apoptosis in AGS cells through activating the caspase cascade via the mitochondrial and Fas/FasL pathway, GADD expression, and by modifying cell cycle progress and changes in several cycle-regulating proteins. The induction of apoptosis by pterostilbene may provide a pivotal mechanism of the antitumor effects and for treatment of human gastric cancer.     

Role of the lithogenic basis in the diversity of soddy podburs in Transbaikalia

The preferential distribution of soddy podburs on loose sandy sediments of different genesis, as well as the possibility of their formation on loess-like carbonate rocks and, in rare cases, on the eluvium of metamorphic biotite–chlorite shales, has been revealed. The differences in the microstructure, composition, and properties of soils are due to the impact of different soil-forming rocks. The results of study will contribute to the classification of regional soils and the optimization of forest and agricultural land use.