The HO-1-expressing bone mesenchymal stem cells protects intestine from ischemia and reperfusion injury.

BACKGROUND: Bone mesenchymal stromal cells (BMSC) showed protective potential against intestinal ischemia. Oxygenase-1(HO-1) could alleviate oxidative stress. In the present study, we constructed HO-1-expressing BMSC and detected the effects of it on survival, intestinal injury and inflammation following intestinal ischemia and reperfusion injury (I/R). METHODS: In this experiment, eighty adult male mice were divided into Sham, I/R, I/R + BMSC, I/R + BMSC/HO-1 groups. Mice were anesthetized and intestinal I/R model were established by temporarily occluding the superior mesenteric artery for 60 min with a non-crushing clamp. Following ischemia, the clamp was removed and the intestines were allowed for reperfusion. Prior to abdominal closure, BMSC/ HO-1 (2 × 106 cells) or BMSC (2 × 106 cells) were injected into the peritoneum of I/R mice respectively. Mice were allowed to recover for 24 h and then survival rate, intestinal injury and inflammation were determined. Reactive oxygen species (ROS) was assayed by fluorescent probe. TNFα and IL-6 were assayed by ELISA. RESULTS: BMSC/HO-1 increased seven day survival rate, improved intestinal injury and down-regulated inflammation after intestinal I/R when compared with sole BMSC (p < 0.05 respectively). Multiple pro-inflammatory media were also decreased following application of BMSC/HO-1, when compared with sole BMSC (p < 0.05) respectively, suggesting that BMSC /HO-1 had a better protection to intestinal I/R than BMSC therapy. CONCLUSION: Administration of BMSC/HO-1 following intestinal I/R, significantly improved intestinal I/R by limiting intestinal damage and inflammation.

Fabrication of regular ZnO/TiO2 heterojunctions with enhanced photocatalytic properties.

Facet-selective growth: Regular ZnO/TiO2 heterojunctions have been successfully synthesized using a facile hydrothermal technique (see figure). Due to the interfacial lattice matching, wurtzite ZnO can only grow on the eight {101} facets of the anatase TiO2 single crystals, while the other two {001} facets are untouched. The as-prepared regular ZnO/TiO2 heterojunctions exhibited enhanced photocatalytic generation of (·)OH radicals and enhanced photodegradation of methyl orange when irradiated with UV light.

Cu-Cu2O-TiO2 nanojunction systems with an unusual electron-hole transportation pathway and enhanced photocatalytic properties.

Multicomponent Cu-Cu2O-TiO2 nanojunction systems were successfully synthesized by a mild chemical process, and their structure and composition were thoroughly analyzed by X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy, and X-ray photoelectron spectroscopy. The as-prepared Cu-Cu2O-TiO2 (3 and 9 h) nanojunctions demonstrated higher photocatalytic activities under UV/Vis light irradiation in the process of the degradation of organic compounds than those of the Cu-Cu2O, Cu-TiO2, and Cu2O-TiO2 starting materials. Moreover, time-resolved photoluminescence spectra demonstrated that the quenching times of electrons and holes in Cu-Cu2O-TiO2 (3 h) is higher than that of Cu-Cu2O-TiO2 (9 h); this leads to a better photocatalytic performance of Cu-Cu2O-TiO2 (3 h). The improvement in photodegradation activity and electron-hole separation of Cu-Cu2O-TiO2 (3 h) can be ascribed to the rational coupling of components and dimensional control. Meanwhile, an unusual electron-hole transmission pathway for photocatalytic reactions over Cu-Cu2O-TiO2 nanojunctions was also identified.