Dihydroartemisinin inhibits the expression of von Willebrand factor by downregulation of transcription factor ERG in endothelial cells.

Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, has effective antitumor and anti-inflammatory actions. von Willebrand factor (vWF), a large multifunctional glycoprotein, has a prominent function in hemostasis and is a key factor in thrombus formation. In addition, vWF has been regarded as a prospective biomarker for the diagnosis of endothelial dysfunction. In our experiment, we observed that 25 µM DHA specifically downregulated the expression of vWF mRNA and protein in human umbilical vein endothelial cells (HUVECs). Further investigations demonstrated that this DHA-decreased vWF expression was mediated by the transcription factor ERG and not GATA3. Luciferase activity assay confirmed that DHA regulated the ERG binding with the -56 ETS-binding motif on the human vWF promoter. Thus, the -56 ETS motif on the vWF promoter region regulates the expression of vWF gene which is induced by DHA. Taken together, we proved that DHA decreased the vWF transcription through the downregulation of ERG in HUVECs. As vWF plays a key role in vascular homeostasis, our findings suggest a new role of DHA in vascular diseases.

[Arthroscopic treatment of irreducible hip posterior dislocation caused by acetabular labrum bony Bankart lesions].

OBJECTIVE: To investigate the effectiveness of arthroscopic treatment for irreducible hip posterior dislocation caused by acetabular labrum bony Bankart lesions. METHODS: Between February 2008 and August 2016, 11 patients with irreducible hip posterior dislocation caused by acetabular labrum bony Bankart lesions, were treated with arthroscopic reduction and fixation of bony Bankart lesions. There were 7 males and 4 females, with an average age of 23.7 years (mean, 15-36 years). The injury was caused by traffic accident in 8 cases and falling from height in 3 cases. The interval between hip dislocation and the first manual reduction was 2-8 hours (mean, 5.3 hours) and between the first manual reduction and arthroscopic surgery was 6-31 days (mean, 12.8 days). The preoperative visual analogue scale (VAS) was 5.2±0.9, the modified Harris score was 32±8, and the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) was 30±5. RESULTS: The operative time was 90-150 minutes (mean, 120.9 minutes), with no hip arthroscopic surgery related complications. All incisions healed by first intention. All patients were followed up 26-68 months (mean, 42.7 months). Postoperative X-ray films showed that all hip joints were reduction; CT showed that the reduction of posterior acetabular wall fracture was satisfactory. And all fractures healed at last follow-up with no avascular necrosis of the femoral head or osteoarthritis. At last follow-up, the VAS score was 0.5±0.5, the modified Harris score was 94±5, and the WOMAC score was 95±4. There were significant differences in those indexes between pre- and post-operation ( P<0.05). CONCLUSION: The irreducible hip posterior dislocation caused by acetabular labrum bony Bankart lesions is rare. Arthroscopic therapy has the advantages of less trauma, quick recovery, and less complications.

Effects of three-layered nanodisk size on cell detection sensitivity of plasmon resonance biosensors.

The double resonance plasmonic biosensors based on Au nanodisks (NDs) with a thin SiO2 spacer between the top and bottom Au layers were employed to detect MCF-7 breast cancer cells. The hybridized modes between the localized surface plasmon resonance of Au NDs and the gap coupling resonance of NDs with the Au film underneath have been observed. These multiple metallic layer NDs exhibit higher sensitivity than the common single metallic layer NDs. The extinction spectra showed double resonance bands that could be tailored by varying the ND size. Three sizes of multiple layer NDs ranging from 60 to 200 nm diameter (dia.) were generated and their refractive sensitivity to the surrounding media were analyzed for cell detection. Nanodisks with 120 dia. showed the highest refractive sensitivity up to 230 nm/refractive index unit. These sensors could be used to detect a broad range of MCF-7 cells from a low cell concentration down of 1.0×10(3)cells/ml up to a high cell concentration of 1.7×10(7) cells/ml.

Fiber-coupled laser-driven flyer plates system.

A system for the launch of hypervelocity flyer plates has been developed and characterized. Laser-driven flyers were launched from the substrate backed aluminum-alumina-aluminum sandwiched films. A laser-induced plasma is used to drive flyers with typical thickness of 5.5 µm and diameters of less than 1 mm, to achieve velocities of a few km/s. These flyer plates have many applications, from micrometeorite simulation to laser ignition. The flyer plates considered here have up to three layers: an ablation layer, to form plasma; an insulating layer; and a final, thicker layer that forms the final flyer plates. This technique was developed aiming at improving the energy efficiency of the system. The kinetic energy of flyers launched with the additional layer was found to be enhanced by a factor of near 2 (up to 30%). The optical fiber delivery system governs the output spatial profile of the laser spot and power capacity. Moreover, a technique for coupling high-power laser pulses into an optical fiber has been developed. This fiber optic system has been successfully used to launch flyer plates, and the surface finishing quality of the fiber was found to be an important factor. Importantly, measurements of the flyer performance including the mean velocities and planarity were made by an optical time-of-arrival technique using an optical fiber array probe, demonstrating the good planarity of the flyer and the achievable average velocity of 1.7 km/s with approaching 1 mm diameter. Finally, the relationship between flyer velocities and incident laser pulses energy was also investigated.