ABSTRACT
ObjectiveTo investigate the effect of betulinic acid （BA） on apoptosis and autophagy of human colorectal cancer SW620 cells and the regulatory role of phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt）/mammalian target of rapamycin （mTOR） signaling pathway. MethodCell viability was detected by methyl thiazolyl tetrazolium （MTT） colorimetry to determine the optimal administration time and dosage for subsequent experiments. Four groups were designed， including blank group and low-， medium-， and high-dose BA groups. Hematoxylin-eosin （HE） staining was conducted for the observation of SW620 cell morphology， and annexin-V/propidium iodide double staining for the determination of apoptosis rate in SW620 cells. Hoechst33258 staining and MDC staining were used for the observation of apoptosis and autophagy， respectively. Western blotting was employed to determine the protein levels of B-cell lymphoma/leukemia-2（Bcl-2）-associated X protein （Bax）， aspartate proteolytic enzyme-9 （Caspase-9）， activated aspartate proteolytic enzyme-3 （cleaved Caspase-3）， microtubule-associated protein 1 light chain 3 （LC3）， the mammalian homolog of yeast Atg6 （Beclin-1）， p62， phosphorylated PI3K （p-PI3K）， phosphorylated Akt （p-Akt）， and phosphorylated mTOR （p-mTOR） in SW620 cells. ResultBA inhibited the activity of SW620， HT29， and HCT116 cells in a concentration- and time-dependent manner. The cells treated with BA for 48 h had lower viability than those treated for 24 h （P<0.05， P<0.01）. The half maximal inhibitory concentration (IC50） value of BA at the time point of 48 h was also lower than that at the time point of 24 h （P<0.01）， and that for SW620 cells was the minimum. BA induced the apoptosis in a concentration-dependent manner and increased the autophagosomes. Compared with the blank group， BA increased the apoptosis rate （P<0.01）， up-regulated the protein levels of Bax， Caspase-9， cleaved Caspase-3， and LC3 Ⅱ （P<0.05， P<0.01）， and down-regulated the protein levels of p62， p-Akt， p-PI3K， and p-mTOR （P<0.01）. Additionally， medium- and high-dose BA up-regulated the protein level of beclin-1 （P<0.01）. ConclusionBA may inhibit the activity of SW620 cells by hindering the PI3K/Akt/mTOR signaling pathway to induce cell apoptosis and autophagy.
ABSTRACT
Objective@#To investigate the effect of intracoronary administration of nicorandil prior to primary percutaneous coronary intervention (PPCI) on myocardial perfusion and short-term clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI).@*Methods@#A total of 158 patients with STEMI undergoing PPCI from January 2014 to December 2015 in Fuzhou General Hospital were enrolled consecutively in this prospective controlled randomized trial. Patients were assigned into three groups with random number table: the nicorandil group (patients received intracoronary administration of 6 mg nicorandil after guide wire or balloon successfully crossed the target lesion, n=53), the nitroglycerin group (patients received intracoronary administration of 300 μg nitroglycerin after after guide wire or balloon successfully crossed the target lesion, n=52) and the control group(patients received routine treatment, n=53). The primary outcomes were myocardial perfusion, including the levels of corrected TIMI frame count (cTFC), and the incidence of no reflow or slow flow after PPCI. The secondary outcomes included the incidence of major adverse cardiovascular events (MACE) during hospitalization (all-cause death, reperfusion arrhythmia within 2 hours after PPCI, angina within 24 hours after PPCI, new heart failure or worsening cardiac function, and repeat revascularization) and within 3 months of follow-up (all-cause death, nonfatal myocardial infarction, repeat revascularization, post-infarction angina, and re-hospitalization for congestive heart failure).@*Results@#The age of enrolled patients was (62.9±11.3) years old, and 130 cases (82.3%) of them were male. The median time of symptom-onset to balloon was 4.50 (3.20, 6.43) hours. There were significantly difference in cTFC immediately after PPCI((21.68±7.43)frames, (24.74±8.66)frames, and(27.06±10.40)frames), incidence of no reflow or slow flow after PPCI(5.7%(3/53), 13.5%(7/52), and 22.6%(12/53)), ST-segment resolution at 2 hours after procedure(90.6%(48/53), 84.6%(44/52), and 74.5%(38/53)), and reperfusion arrhythmia at 2 hours after procedure(15.1%(8/53), 36.6%(19/52), and 34.0%(18/53)) among the 3 groups(P<0.01 or 0.05). In the multivariate logistic regression models, intracoronary administration of nicorandil could lower the cTFC level (OR=0.17, 95%CI 0.10-0.41, P=0.001), acted as a protecting factor on lowering the incidence of no reflow or slow flow (OR=0.13, 95%CI 0.02-0.96, P=0.045) and reperfusion arrhythmia (OR=0.26, 95%CI 0.09-0.74, P=0.012), as well as facilitating the ST-segment resolution at 2 hours after procedure (OR=4.62, 95%CI 1.14-18.82, P=0.033). However, observed parameters were similar between intracoronary administration of nitroglycerin group compared with control group (all P>0.05). MACE within 3 months of follow-up were similar among the 3 groups(all P>0.05).@*Conclusion@#Intracoronary administration of nicorandil prior to balloon dilation can significantly improve the myocardial perfusion and reduce the occurrence of reperfusion arrhythmia during PPCI for STEMI, but does not affect the short-term prognosis in STEMI patients.
ABSTRACT
Objective To explore the occupational stressors and the coping strategies in the newly-employed nurses and to explore their relationships. Method The survey was done among 193 registered nurses with less than 3 years working experience using the occupational stressor scale for Chinese nurses, the simplified coping strategies questionnaire and a self-designed general demography form. Results The total score on occupational stressors was 2.27 ± 0.56, which was at a common level. Postive and negative coping style were 1.88 ± 0.44 and 1.04 ± 0.51. The stressors together with the dimensions were positively correlated with negative coping strategies (P<0.05). Conclusion Nursing administration should improve work environment, provide enough manpower for patient care, carry out training system to focus on education for newly employed nurses, and provide advice and help for them when they need.