[Effects of Monoammonium Glycyrrhizinate on Stem Cell-like Characteristics, Oxidative Stress and Mitochondrial Function of Acute Promyelocytic Leukemia NB4 Cells].

OBJECTIVE: To investigate the effect of monoammonium glycyrrhizinate on the stem cell-like characteristics, oxidative stress and mitochondrial function of acute promyelocytic leukemia cells NB4. METHODS: CCK-8 method was used to detect the viability of acute promyelocytic leukemia cells NB4, and the appropriate dose was screened; Cloning method was used to detect the proliferation rate of NB4 cell; Western blot was used to detect the expression of cell cycle-related protein; flow cytometry was used to detect cell apoptosis and sort NB4 stem cells positive (CD133+); Stem cell markers (Oct4, ABCG2, Dclk1) were detected by RT-PCR; ROS was detected by fluorescence; The kit was used to detect the level of oxidative stress markers (MDA); The flow cytometry was used to detect the change of mitochondrial membrane potential; Western blot was used to detect the expression of mitochondrial damage index-related proteins (Bax/BCL-2). RESULTS: Compared with the control group, if the concentration of MAG was less than 5 µmol/L, the cell NB4 viability showed no significant difference; if the concentration was higher than 5 µmol/L, the inhibitory effect on the growth of cell NB4 increased and showed significant difference (P<0.05), according to the results of CCK-8 experiment, four groups were set based on the concentration of MAG 0 µmol/L, MAG 5 µmol/L, MAG 10 µmol/L, and MAG 20 µmol/L; compared with the control group (MAG 0 µmol/L), the cells in MAG 5 µmol/L group showed no significant difference, while the proliferation rate, cyclin expression, mitochondrial membrane potential, stem cell CD133+ ratio, and marker mRNA level ( Oct4, ABCG2, Dclk1) of NB4 cell were significantly reduced (P<0.05); the apoptosis rate, reactive oxygen species, MDA content and Bax/BCL-2 expression of NB4 cell significantly increased (P<0.05). CONCLUSION: Monoammonium glycyrrhizinate has a significant inhibitory effect on acute promyelocytic leukemia cells NB4, which may be related to the regulation of stem cell-like characteristics, oxidative stress and mitochondrial function.

Incidence and Related Factors for Hospital-Acquired Pneumonia Among Older Bedridden Patients in China: A Hospital-Based Multicenter Registry Data Based Study.

Objective: To identify the incidence and related factors for hospital-acquired pneumonia (HAP) among older bedridden patients in China. Study design and setting: This multicenter registry data-based study conducted between November 2015 and March 2016 surveyed 7,324 older bedridden patients from 25 hospitals in China (six tertiary, 12 non-tertiary, and seven community hospitals). The occurrence of HAP among all participants was monitored by trained investigators. Demographics, hospitalization information and comorbidity differences were compared between patients with and without HAP. A multilevel regression analysis was used to explore the factors associated with HAP. Results: Among 7,324 older bedridden patients, 566 patients were diagnosed with HAP. The incidence of HAP in this study was 13.9 per 1,000 person-days. There were statistical differences in gender, age, length of bedridden days, BMI, smoking, department, undergoing general anesthesia surgery, ventilator application, Charlson comorbity index (CCI) score, disturbance of consciousness, tranquilizer use, glucocorticosteroid use, and antibiotic use between patients with HAP and patients without HAP (all p < 0.05). Multilevel regression analysis found no significant variance for HAP at the hospital level (0.332, t = 1.875, p > 0.05). There were significant differences for the occurrence of HAP among different departments (0.553, t = 4.320, p < 0.01). The incidence density of HAP was highest in the ICU (30.1‰) among the selected departments, followed by the departments of neurosurgery (18.7‰) and neurology medicine (16.6‰). Individual patient-level factors, including older age, disturbance of consciousness, total CCI score, ICU admission, and glucocorticoid and antibiotic use, were found to be associated with the occurrence of HAP (all p < 0.05). Conclusion: A relatively high incidence density of HAP among older bedridden patients was identified, as well as several factors associated with HAP among the population. This suggests that attention should be paid to the effective management of these related factors of older bedridden patients to reduce the occurrence of HAP.