Nuclear Magnetic Resonance-Based Metabolomics Approach to Evaluate the Prevention Effect of Camellia nitidissima Chi on Colitis-Associated Carcinogenesis.

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide, occurring in the colon or rectum portion of large intestine. With marked antioxidant, anti-inflammation and anti-tumor activities, Camellia nitidissima Chi has been used as an effective treatment of cancer. The azoxymethane/dextran sodium sulfate (AOM/DSS) induced CRC mice model was established and the prevention effect of C. nitidissima Chi extracts on the evolving of CRC was evaluated by examination of neoplastic lesions, histopathological inspection, serum biochemistry analysis, combined with nuclear magnetic resonance (NMR)-based metabolomics and correlation network analysis. C. nitidissima Chi extracts could significantly inhibit AOM/DSS induced CRC, relieve the colonic pathology of inflammation and ameliorate the serum biochemistry, and could significantly reverse the disturbed metabolic profiling toward the normal state. Moreover, the butanol fraction showed a better efficacy than the water-soluble fraction of C. nitidissima Chi. Further development of C. nitidissima Chi extracts as a potent CRC inhibitor was warranted.

Dressings for Preventing Pressure Ulcers: A Meta-analysis.

The purpose of this analysis is to determine the effectiveness of dressing material in the prevention of pressure ulcers. Results showed that hydrocolloid, foam, and film were more effective than a standard care protocol in patients at risk for pressure ulcers.

In vivo magnetic resonance imaging tracking of transplanted superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells in rats with myocardial infarction.

Superparamagnetic iron oxide (SPIO) nanoparticles generate superparamagnetism, thereby resulting in an inhomogeneous local magnetic field, which shortens the T2 value on magnetic resonance imaging (MRI). The purpose of the present study was to use MRI to track bone marrow mesenchymal stem cells (BMSCs) labeled with SPIO in a rat model of myocardial infarction. The BMSCs were isolated from rats and labeled with SPIO. The anterior descending branch of the coronary artery was ligated under anesthesia. Two weeks later, the rats received, at random, 5 x 10(7) SPIO-labeled BMSCs, 5 x 10(7) unlabeled BMSCs or a vehicle (100 µl phosphate-buffered saline) via direct injection into the ischemic area (20 animals/group). MRI was used to track the SPIO­labeled BMSCs and the rats were then sacrificed to verify the presence of BMSCs using immunohistochemistry with an anti-CD90 antibody. The procedure labeled 99% of the BMSCs with SPIO, which exhibited low-intensity signals on T2 and T2* MRI imaging. At 24 h post-BMSC transplantation, low-intensity MRI signals were detected on the T2 and T2* sequences at the infarction margins. After 3 weeks following transplantation, low-intensity signals started to appear within the infarcted area; however, the signal intensity subsequently decreased and became indistinct. Immunohistochemistry revealed that the SPIO-labeled BMSCs migrated from the margin into the infarcted region. In conclusion, the BMSCs were readily labeled with SPIO and in vivo and MRI tracking demonstrated that the SPIO-labeled BMSCs established and grew in the infarcted myocardium.

Inhibition of apoptosis by knockdown of caspase-3 with siRNA in rat bone marrow mesenchymal stem cells.

Transplantation of bone marrow mesenchymal stem cells is a promising new strategy for the repair of infarcted cardiac tissue. However, the majority of transplanted bone marrow mesenchymal stem cells (BMSCs) die soon after transplantation, due in part to oxidative stress in the ischemic region. Oxidative stress is known to induce apoptosis through the activation of caspase-3. The aim of this study is to determine whether small interfering RNA targeting caspase-3 can inhibit the apoptosis of rat BMSCs in vitro. Caspase-3 siRNA expression vectors were prepared and transfected into rat BMSCs in the presence of liposomes. Western blot assay and real-time polymerase chain reaction (RT-PCR) were performed to detect caspase-3 expression. A retrovirus packaging system was employed to package 293FT cells producing caspase-3 siRNA virus, which were transfected into rat BMSCs. Those stably expressing caspase-3 siRNA were screened by Western blot assay and RT-PCR to determine caspase-3 expression levels. Stable transfection of caspase-3 siRNA significantly decreased caspase-3 protein (0.26 ± 0.001 vs. 0.42 ± 0.004, P < 0.05) and mRNA expression (0.19 ± 0.002 vs. 1, P < 0.05) in BMSCs compared to non-transfected BMSCs. Cells were incubated in H2O2 to induce apoptosis, which was detected by TUNEL staining, and BMSC morphology was not altered by either transient or stable transfection of caspase-3 siRNA. H2O2-induced apoptosis of BMSCs stably transfected with caspase-3 siRNA was dramatically reduced compared to that of normal BMSCs (11.0 ± 3.2 vs. 25.8 ± 4.2, P < 0.05). Caspase-3 knockdown BMSCs are thus more resistant to apoptosis than normal BMSCs, potentially increasing their survival rates under conditions that cause oxidative stress.