In vitro inhibitory effect of zingerone on TNFα-stimulated fibroblast-like synoviocytes.

Targeting Fibroblast-like synoviocytes (FLSs) is an attractive complementary approach for RA therapy. This study aimed to investigate the inhibitory effects of zingerone on TNFα-induced arthritic FLSs. MTS, EdU, wound healing, DHE staining and real-time PCR were used to determine the effects of zingerone on the destructive behaviors of arthritic FLSs induced by TNFα. Western blot analysis was used to analyze cell signaling pathways. Zingerone treatment significantly inhibited TNFα-induced proliferation, migration, ROS formation and pro-inflammatory cytokines expression of FLSs. Molecular mechanism studies revealed that zingerone could suppress TNFα-induced activations of MAPKs (ERK, JNK and p38) in arthritic FLSs. Zingerone attenuated pathological features of FLSs via MAPKs pathways, indicating its potential as a complementary or alternative drug for RA therapy.

Peimine suppresses collagen-induced arthritis, activated fibroblast-like synoviocytes and TNFα-induced MAPK pathways.

BACKGROUND AND PURPOSE: Peimine (PM), a main isosterol alkaloid component isolated from the bulbs of traditional Chinese herb Fritillaria cirrhosa D. Don, has been demonstrated to exhibit multiple pharmacological properties, including anti-inflammation, anti-cancer and pain suppression. However, its effect on rheumatoid arthritis (RA) remains unknown. In the present study, we investigated the effect of PM on collagen-induced arthritis (CIA) rats in vivo and its inhibition on destructive behaviors of arthritic fibroblast-like synoviocytes (FLSs) in vitro. METHODS: Arthritis was induced in rats by chicken type II collagen. Arthritis score, radiological evaluation, and histopathological assessment were used to evaluate the therapeutic effects of PM on CIA rats. EdU assay, wound healing assay and real-time PCR were used to examine the inhibitory effect of PM on proliferation, migration, and over-expression of pro-inflammatory cytokines in TNFα-induced arthritic FLSs. TRAP staining and scanning electron microscopy were used to analyze the effect of PM on osteoclastogensis and bone resorption. Western blot was used to reveal PM's molecular mechanism of action on RA. RESULTS: PM significantly suppressed synovitis and bone destruction in CIA rats. In vitro experiments showed that PM treatment significantly inhibited TNFα-induced destructive behaviors of arthritic FLSs, including over-proliferation, migration and over-expression of pro-inflammatory cytokines. Additionally, RANKL-induced osteoclast formation and bone-resorpting function were also inhibited by PM. Further molecular mechanism studies revealed that PM treatment significantly suppressed TNFα-induced activations of MAPKs (ERK, JNK and p38) in arthritic FLSs. CONCLUSION: Our findings provide strong evidence that PM has the potential to be developed as a therapeutic agent for patients with RA.

Observation of Strong Reflection of Electron Waves Exiting a Ballistic Channel at Low Energy.

Wave scattering by a potential step is a ubiquitous concept. Thus, it is surprising that theoretical treatments of ballistic transport in nanoscale devices, from quantum point contacts to ballistic transistors, assume no reflection even when the potential step is encountered upon exiting the device. Experiments so far seem to support this even if it is not clear why. Here we report clear evidence of coherent reflection when electron wave exits the channel of a nanoscale transistor and when the electron energy is low. The observed behavior is well described by a simple rectangular potential barrier model which the Schrodinger's equation can be solved exactly. We can explain why reflection is not observed in most situations but cannot be ignored in some important situations. Our experiment also represents a direct measurement of electron injection velocity - a critical quantity in nanoscale transistors that is widely considered not measurable.

Top-down fabrication of vertical silicon nano-rings based on Poisson diffraction.

Vertical Si nano-rings with a uniform thickness of about 100 nm have been fabricated by conventional optical photolithography with a low cost based on Poisson diffraction. Moreover, the roughness of the Si nano-rings can be effectively reduced by sacrificial oxidation. In order to increase the density of the nano-rings, coaxial twin Si nano-rings have been fabricated by the Poisson diffraction method combined with the spacer technique. The thickness of both the inner and outer Si nano-rings is about 60 nm, and the gap between the twin nano-rings is about 100 nm.