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Xylopiana A (1), a dimeric guaiane with an unprecedented pentacyclo[5.2.1.0 1,2 .0 4,5' .0 5,4' ]decane-3,2'-dione core, and three biosynthetically related intermediates, compounds 2-4, were isolated from the leaves of Xylopia vielana. Their structures and absolute configurations were determined by a combination of spectroscopic data, X-ray crystallography, electronic circular dichroism calculations, and chemical conversion. The structure of known vielanin A was revised to be compound 3. Compound 4 exerted a 3.7-fold potentiation effect on doxorubicin susceptibility at the tested concentration of 10 μM.

FIP-gat, an immunomodulatory protein isolated from Ganoderma atrum, is a new member of the FIP family. Little is known, however, about its expressional properties and antitumor activities. It was availably expressed in Escherichia coli with a total yield of 29.75 mg/L. The migration of recombinant FIP-gat (rFIP-gat) on SDS-PAGE corresponded to the predicted molecular mass, and the band was correctly detected by a specific antibody. To characterize the direct effects of rFIP-gat on MDA-MB-231 breast cancer cells, MDA-MB-231 cells were treated with different concentrations of rFIP-gat in vitro; the results showed that this protein could reduce cell viability dose-dependently with a median inhibitory concentration (IC50) of 9.96 μg/mL and agglutinate the MDA-MB-231 cells at a concentration as low as 5 μg/mL. Furthermore, FIP-gat at a concentration of 10 μg/mL can induce significant growth inhibition and cell death in MDA-MB-231 cells. Notably, FIP-gat treatment triggers significant cell cycle arrest at the G1/S transition and pronounced increase in apoptotic cell population. Molecular assays based on microarray and real-time PCR further revealed the potential mechanisms encompassing growth arrest, apoptosis, and autophagy underlying the phenotypic effects.

A photoplatinization technique was proposed to deposit Pt on a thin TiO(2) layer modified indium tin oxide-coated polyethylene naphthalate (ITO/PEN) substrate at low temperature (about 50 °C after 1 h of UV irradiation) for the first time. The fabrication process includes coating and hydrolyzing the tetra-n-butyl titanate to form a TiO(2)-modified layer and the photoplatinization of the modified substrate in H(2)PtCl(6)/2-propanol precursor solution under UV irradiation. The obtained platinized electrodes were used as counter electrodes (CE) for flexible dye-sensitized solar cells (FDSCs). The well-optimized platinized electrode showed high optical transmittance, up to 76.5% between 400 and 800 nm (T(av)), and the charge transfer resistance (R(ct)) was as low as 0.66 Ω cm(2). A series of characterizations also demonstrated the outstanding chemical/electrochemical durability and mechanical stability of the platinized electrode. The FDSCs with TiO(2)/Ti photoanodes and the obtained CEs achieved a power conversion efficiency (PCE) up to 8.12% under rear-side irradiation (AM 1.5 illumination, 100 mW cm(-2)). The obtained CEs were also employed in all-plastic bifacial DSCs. When irradiated from the rear side, the bifacial FDSC yielded a PCE of 6.26%, which approached 90% that of front-side irradiation (6.97%). Our study revealed that, apart from serving as a functional layer for deposition of Pt, the thin TiO(2) layer modification on ITO/PEN substrates also played an important role in improving the transparency and the mechanical properties of the CE. The effect of the thickness of the TiO(2) layer for Pt coating on the performance of the CE was also investigated.

Cardol triene was first purified from cashew (Anacardium occidentale L.) nut shell liquid and identified by gas chromatography coupled to mass spectroscopy and nuclear magnetic resonance. The effects of this compound on the activity of mushroom tyrosinase were studied. The results of the kinetic study showed that cardol triene was a potent irreversible competitive inhibitor and the inactivation was of the complexing type. Two molecules of cardol triene could bind to one molecule of tyrosinase and lead to the complete loss of its catalytic activity. The microscopic rate constants were determined for the reaction of cardol triene with the enzyme. The anti-tyrosinase kinetic research of this study provides a comprehensive understanding of inhibitory mechanisms of resorcinolic lipids and is beneficial for the future design of novel tyrosinase inhibitors.

2-Chlorobenzaldehyde thiosemicarbazone (2-Cl-BT) and 4-chlorobenzaldehyde thiosemicarbazone (4-Cl-BT) were synthesized, and their inhibitory kinetics on the activity of mushroom tyrosinase were investigated. Results showed that these compounds exhibited significant inhibitory potency on both monophenolase activity and diphenolase activity of tyrosinase. For the monophenolase activity, both compounds could decrease the steady-state activity of the enzyme sharply, without any influence on the lag period. The IC50 values of them were estimated to be 15.4 μM and 6.7 μM, respectively. For the diphenolase activity, both compounds belonged to reversible inhibitors, but their mechanisms were different: 2-Cl-BT was a noncompetitive type inhibitor, while 4-Cl-BT was a mixed-type inhibitor. Their inhibition constants were determined and compared.

Defects of kinase-phosphatase signaling in cardiac myocytes contribute to human heart disease. The activity of one phosphatase, PP2A, is governed by B targeting subunits, including B56gamma1, expressed in heart cells. As the role of PP2A/B56gamma1 on the heart function remains largely unknown, this study sought to identify protein partners through unbiased, affinity purification-based proteomics combined with the functional validation. The results reveal multiple interactors that are localized in strategic cardiac sites to participate in Ca2+ homeostasis and gene expression, exemplified by the Ca pump, SERCA2a, and the splicing factor ASF/SF2. These results are corroborated by confocal imaging where adenovirally overexpressed B56gamma1 is found in z-line/t-tubule region and nuclear speckles. Importantly, overexpression of B56gamma1 in cultured myocytes dramatically impairs cell contractility. These results provide a global view of B56gamma1-regulated local signaling and heart function.