ABSTRACT
A green lighting upconversion (UC) system was successfully achieved from Er3+/Yb3+ co-doped BaMoO4 synthesized by the complex citrate-gel method. Under 980 nm laser excitation, the Er3+/Yb3+ co-doped BaMoO4 emitted strong green luminescence around 530 and 550 nm and weak red luminescence near 660 nm, which corresponded to the intra 4f-4f transitions in Er3+. Optimal doping concentrations of Er3+/Yb3+ into the BaMoO4 matrix were investigated. Moreover, based on excitation power dependence, the UC luminescent mechanism in the Er3+/Yb3+ co-doped BaMoO4 was presented in detail.
ABSTRACT
Selective estrogen receptor modulators (SERMs) are synthetic molecules which bind to estrogen receptors (ER) and can modulate its transcriptional capabilities in different ways in diverse estrogen target tissues. Tamoxifen, the prototypical SERM, is extensively used for targeted therapy of ER positive breast cancers. Unfortunately, the use of tamoxifen is associated with acquired resistance and some undesirable side effects. This study investigated the availability of the conventional SERMs on the TAM-resistance breast cancer cells. SERMs showed more effectiveness in MCF-7 cells than tamoxifen resistant cells, except toremifene and ospemifene. Especially, toremifene was more efficacious in tamoxifen resistant cells than MCF-7. Ospemifene had similar cytotoxic activity on the two types of breast cancers. The other SERMs used in this experiment didn't inhibit efficiently the proliferation of tamoxifen resistant cells. These results support the possibility to usage of toremifene on tamoxifen resistant cancer. The effectiveness by toremifene on tamoxifen resistant cells might be different pathways from the apoptosis and the autophagy. Further study should be needed to elucidate the underlying mechanism of effect of toremifene on tamoxifen resistant cancer.
