Phosphatidylinositol 3-kinase inhibitor(LY294002) induces apoptosis of human nasopharyngeal carcinoma in vitro and in vivo

BACKGROUND: To evaluate whether PI3K/Akt pathway could effect on apoptosis and its mechanism in nasopharyngeal carcinoma cells. METHODS: The activation of the PI3K/Akt and its effect on CNE-2Z cells in vivo and in vitro was investigated by MTT assay, flow cytometry, western blot, ELISA, terminal deoxyribonucleotide transferase-mediated nick-end labeling assays (TUNEL), and immunohistochemical analyses, using PI3K inhibitor, LY294002. RESULTS: The results showed that LY294002 inhibited the phosphorylating of Akt (S473), cell proliferation, and induced apoptosis in CNE-2Z cells. However, our experiment results also demonstrated that apoptosis-induced LY294002 was directly regulated by caspase-9 activation pathway. CONCLUSION: These data suggested that PI3K inhibitor, LY294002, induced apoptosis by caspase-9 activation pathway and might be as a potentially useful target for therapeutic intervention in nasopharyngeal carcinoma patients

Effects of Post Treatments on Bismuth-Doped and Bismuth/ Erbium Co-doped Optical Fibres

Bismuth-doped and bismuth/erbium co-doped optical fibres have attracted much attention for their great potential in the photonic applications at ultrawide O, E, S, C and L bands. The effects of post treatments, including various heating, high energy ray radiation, laser radiation and H2 loading processes, on these fibres’ performance, functionality and stability have been experimentally studied. Experimental results demonstrate that these post treatments could allow us to get insights regarding the formation and the structure of bismuth active centre (BAC) and be used to control and regulate the formation of BAC

Studying trabecular bone samples demonstrates a power law relation between deteriorated structure and mechanical properties - a study combining 3D printing with the finite element method

IntroductionThe bone volume fraction (BV/TV) significantly contributes to the mechanical properties of trabecular bone. However, when studies compare normal trabeculae against osteoporotic trabeculae (in terms of BV/TV decrease), only an “average” mechanical result has been determined because of the limitation that no two trabecular structures are the same and that each unique trabecular structure can be mechanically tested only once. The mathematic relation between individual structural deterioration and mechanical properties during aging or the osteoporosis process has yet to be further clarified. Three-dimensional (3D) printing and micro-CT-based finite element method (μFEM) can assist in overcoming this issue.MethodsIn this study, we 3D printed structural-identical but BV/TV value-attenuated trabecular bones (scaled up ×20) from the distal femur of healthy and ovariectomized rats and performed compression mechanical tests. Corresponding μFEM models were also established for simulations. The tissue modulus and strength of 3D printed trabecular bones as well as the effective tissue modulus (denoted as Ez) derived from μFEM models were finally corrected by the side-artifact correction factor.ResultsThe results showed that the tissue modulus corrected, strength corrected and Ez corrected exhibited a significant power law function of BV/TV in structural-identical but BV/TV value-attenuated trabecular samples. DiscussionUsing 3D printed bones, this study confirms the long-known relationship measured in trabecular tissue with varying volume fractions. In the future, 3D printing may help us attain better bone strength evaluations and even personal fracture risk assessments for patients who suffer from osteoporosis

Transcriptome reveals the immune and antioxidant effects of residual chlorine stress on Cyclina sinensis

Residual chlorine is a common by-product of warm drainage in coastal nuclear power plants. when accumulating to some limit, it may threaten marine ecosystem especially for benthic clam. However, there are few studies on the molecular mechanisms related to immunity and antioxidant of residual chlorine stress on clams. In this study, the clam (Cyclina sinensis) was exposed for 96 h at different concentrations (0, 50, 100, 150, 200, 250, 300, 350, 400, 450 and 500 mg/L) of residual chlorine to observe its mortality, measure the activity of antioxidant and immune-related enzymes, and analyses the gene expression level in the hepatopancreas by using the transcriptome sequencing. The results showed that the mortality rate increased with the increase of stress time and concentration, and the mortality rate in the 400, 450 and 500 mg/L groups reached 100% at 96 h. The tolerance to residual chlorine of C. sinensis decreased with the increase of chlorine dioxide concentration, and the LC50 of 96 h was 217.6 mg/L by linear regression method. After residual chlorine stress, the activity of antioxidant-related enzymes (T-AOC and SOD) in the hepatopancreas showed a trend of first increase and then decrease with the extension of stress time. The immune-related enzyme activities of AKP and LZM showed a downward trend between 0 and 96 h, while the ACP enzyme activity showed a trend of first rising and then decreasing. Transcriptome analysis showed that residual chlorine stress significantly changed the expression levels of immune-related molecules associated with signal transduction, prophenoloxidase cascade, cell apoptosis and pattern recognition protein/receptor. Moreover, glutathione S-transferase (GST), heat shock protein (HSP) and other antioxidant-related genes were significantly affected under residual chlorine stress. This study provided valuable information for understanding the effects of residual chlorine stress on survival, physiological metabolism and molecular mechanisms of immune and antioxidant functions of C. sinensis