Effect of Lidamycin on Telomerase Activity in Human Hepatoma BEL-7402 Cells

Objective To investigate the effect of lidamycin （LDM） on telomerase activity in human hepatoma BEL-7402 cells under the condition of LDM inducing mitotic cell death and senescence. Methods Chromatin condensation was detected by co-staining with Hoechst 33342 and PI. Cell multinucleation was observed by Giemsa staining and genomic DNA was separated by agarose gel electrophoresis. Fluorescent intensity of Rho123 was determined for mitochondrial membrane potential. MTT assay and SA-13-gal staining were employed to analyze the senescence-like phenotype. The expression of proteins was analyzed by Western blot. Telomerase activity was assayed by telomerase PCR-ELISA. Results Mitotic cell death occurred in LDM-treated cells characterized by unique and atypical chromatin condensation, multinucleation and increased mitochondrial membrane potential. However, no apoptotic bodies or DNA ladders were found. In addition, apoptosis-related proteins remained nearly unaltered. Senescence-like phenotype was identified by increased and elongated size of cells, growth retardation, enhanced SA-13-gal activity and the changes of senescence-related protein expression. Telomerase activity markedly decreased （P〈0.01） in LDM-treated hepatoma BEL-7402 cells. Conclusion Mitotic cell death and senescence could be triggered simultaneously or sequentially after exposure of hepatoma BEL-7402 cells to LDM. The decrease in telomerase activity may play a key role in the defective mitosis and aging morphology. Further investigation of detailed mechanism is needed.

Study on timing of preoperative fasting and water deprivation in patients receiving fiberoptic bronchoscopy

Purpose:To compare the effects of different preoperative fasting intervals and water deprivation in patients receiving fiberoptic bronchoscopy(FB).Methods:In total,390 patients receiving FB were divided into two groups.The 200 patients in the experimental group had 100 mL semi-liquid food two hours before FB,and 190 patients in the control group had 250 g ordinary food four hours before FB.The incidence of nausea,vomiting,aspiration,dizziness,and palpitations and vital signs,oxygen saturation,and anxiety level before and after FB were recorded.Results:There was no significant difference in the incidence of nausea,vomiting,aspiration,or palpitations;and respiration rate,heart rate,and oxygen saturation were not different between the two groups(p>0.05).There were,however,significant differences in the incidence of dizziness,comfort level,anxiety,and blood pressure(p<0.05).Conclusion:Intake of 100 mL semi-liquid food two hours prior to FB is safe and feasible.