11 research outputs found
Photo-induced volume changes in selenium. Tight-binding molecular dynamics study
Tight-binding molecular dynamics simulations of photo-excitations in small Se
clusters (isolated Se ring and helical Se chain) and glassy Se networks
(containing 162 atoms) were carried out in order to analyse the photo induced
instability inside the amorphous selenium. In the cluster systems after taking
an electron from the highest occupied molecular orbital to the lowest
unoccupied molecular orbital a bond breaking occurs. In the glassy networks
photoinduced volume expansion was observed and at the same time the number of
coordination defects changed significantly due to illumination
Laser-induced optical changes in amorphous multilayers
It is shown that the well-known blue-shift of the fundamental absorption edge
in as-deposited compositionally modulated amorphous Si/Ge and As6Se94/Se80Te20
multilayers (with periods of 4-8 nm) is further enhanced due to the thermal or
laser-induced intermixing of adjacent layers. The laser-induced intermixing
process, as supported by experiments and model calculations, can be attributed
to both the local heating and photo-effects in As6Se94/Se80Te20 multilayers,
while only the thermal effects were observed for Si/Ge multilayers. Structural
transformations, based on this enhanced interdiffusion, provides good
capability for spatially patterning optoelectronic devices and digital
information recording
Biological activities of fusarochromanone: a potent anti-cancer agent
Background
Fusarochromanone (FC101) is a small molecule fungal metabolite with a host of interesting biological functions, including very potent anti-angiogenic and direct anti-cancer activity. Results
Herein, we report that FC101 exhibits very potent in-vitro growth inhibitory effects (IC50 ranging from 10nM-2.5 μM) against HaCat (pre-malignant skin), P9-WT (malignant skin), MCF-7 (low malignant breast), MDA-231 (malignant breast), SV-HUC (premalignant bladder), UM-UC14 (malignant bladder), and PC3 (malignant prostate) in a time-course and dose-dependent manner, with the UM-UC14 cells being the most sensitive. FC101 induces apoptosis and an increase in proportion of cells in the sub-G1 phase in both HaCat and P9-WT cell lines as evidenced by cell cycle profile analysis. In a mouse xenograft SCC tumor model, FC101 was well tolerated, non-toxic, and achieved a 30% reduction in tumor size at a dose of 8 mg/kg/day. FC101 is also a potent anti-angiogenenic agent. At nanomolar doses, FC101 inhibits the vascular endothelial growth factor-A (VEGF-A)-mediated proliferation of endothelial cells. Conclusions
Our data presented here indicates that FC101 is an excellent lead candidate for a small molecule anti-cancer agent that simultaneously affects angiogenesis signaling, cancer signal transduction, and apoptosis. Further understanding of the underlying FC101’s molecular mechanism may lead to the design of novel targeted and selective therapeutics, both of which are pursued targets in cancer drug discovery