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Guaiane sesquiterpenoids ( 1 , 2 ) were isolated from the gorgonian Menella woodin and their structures elucidated by extensive spectroscopic analysis. A complex approach was used to determine the configurations of the asymmetric centres in these natural products, based on the application of Mosher’s method, and the calculation of stable conformations of the rings along with a comparison of experimental ECD, NMR spectra, and specific optical rotations with those theoretically calculated by quantum-chemical methods. [ABSTRACT FROM AUTHOR]

An abstract of the article "Structures and Absolute Stereochemistry of Guaiane Sesquiterpenoids from the Gorgonian Menella woodin" by C. Diep and colleagues is presented.

Four new polyoxygenated sterol derivatives ( 1 – 4 ) along with the compounds ( 5 – 7 ) previously known from other biological sources were isolated from the gorgonian Menella woodin , collected from the Vietnamese waters. Structures of 1 – 4 were elucidated by the detailed NMR spectroscopic and mass-spectrometric analyses as well as comparison with those reported in literature data. Compounds 1 , 4 , and 6 decrease the production of reactive oxygen species (ROS) by the murine macrophages of RAW 264.7 line at induction by endotoxic lipopolysaccharide (LPS) from Escherichia coli . [ABSTRACT FROM AUTHOR]

The article presents a study which explores that Tankyrase-mediated ADP-ribosylation, a regulator of Tumor necrosis factor (TNF)-induced death . It mentions that findings of the study suggests that disruption of ADP-ribosylation during an infection can prime a cell to retaliate with an inflammatory cell death.

The article presents a study which explores about the Tankyrase-mediated ADP-ribosylation as a regulator of Tumor necrosis factor (TNF)-induced death. It mentions that TNF, a key component of the innate immune response and suggests that disruption of ADP-ribosylation during an infection can prime a cell to retaliate with an inflammatory cell death.

Using combined chromatographic methods, two asterosaponins (compounds1and2), including a new compound novaeguinoside E (compound1), and six glycosylated polyhydroxysteroids (compounds3–8) were isolated from a methanol extract of the starfishCulcita novaeguineae. Their structures were determined on the basis of spectroscopic data (1H and13C NMR, HSQC, HMBC,1H–1H COSY, ROESY, and HRESI-MS) and by comparison with the literature values. The new compound1represents the third example of asterosaponins containing the 5α-cholesta-9(1l)-en-3β,6α,20,22-tetraol aglycone. Among isolated compounds,4–7exhibited moderate to weak cytotoxic activities against five human cancer cell lines such as Hep-G2 (hepatoma), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma). [ABSTRACT FROM AUTHOR]

This study first investigates the preparation and characterization of titanium dioxide/reduced graphene oxide (TiO 2 /rGO) and then proposes the fabrication of photoanode in dye-sensitized solar cell (DSSC) from synthesized materials. Herein, the TiO 2 /rGO nanocomposites were prepared by the incorporation of hydrothermal approach and co-precipitation method from the precursors of titanium (IV) isopropoxide and graphene oxide. The fabrication of photoanode from the as-prepared TiO 2 /rGO nanocomposite paste was carried out using screen-printing technique. The performance of fabricated DSSCs was evaluated by current density-voltage curves and electrochemical impedance spectroscopy. The characterizations of TiO 2 nanoparticles, TiO 2 /rGO nanocomposites, and their precursors were confirmed by ultraviolet-visible spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, and transmission electron microscopy. Experimental data showed that the optimal rGO weight percentage of 0.6% in the TiO 2 /rGO nanocomposite material fabricated DSSC successfully with the highest values of short-circuit current density (17.65 mA/cm2) and energy conversion efficiency (7.46%), approximately increasing 24% and 25%, respectively, in comparison with the pristine TiO 2 material. Characterization results indicated that the incorporated hydrothermal co-precipitation method was efficient in producing well-defined spherical TiO 2 nanoparticles decorated on the rGO sheets with an average diameter of 20–25 nm. Therefore, the TiO 2 /rGO nanocomposites with the eco-friendly and efficient synthesis method are highly promising for manufacturing and commercializing DSSCs widely. [Display omitted] • The TiO 2 /rGO nanocomposite material was efficiently synthesized via the incorporated hydrothermal co-precipitation method. • The TiO 2 /rGO nanocomposite material was used for fabricating photoanode in DSSC using the screen-printing technique. • The rGO weight percentage of 0.6% in the TiO 2 /rGO optimized the DSSC performance with the highest values of J SC , τ n , and η. • The characterization results indicated that TiO 2 nanoparticles with the diameter range of 20–25 nm were attached to the rGO. [ABSTRACT FROM AUTHOR]