ABSTRACT
Objective: To assess the accuracy and application value of type III portable monitor (III PM) of sleep apnea (SA) for in-hospital patients with cardiovascular disease (CVD). Methods: A total of 101 CVD patients received sleep apnea monitoring by both type II polysomnography ( II PSG) and III PM were enrolled to compare the apnea-hypopnea index (AHI) measured by 2 instruments. AHI was assigned into 4 grades: Normal (AHI0.05. Kendall correlation coefficient for 4 AHI grades was 0.701, P<0.01 which assumed strong correlation; Kappa value of consistency was 0.493, P<0.01 which assumed medium strong correlation. Using AHI≥15 as cut-off point, Kappa coefficient for the consistency between II PSG and III PM was 0.679, P<0.05, which meant high consistency. Taking II PSG as standard and AHI≥15 as cut-off point, the AUC of III PM measured AHI was 0.918 with the specificity at 80.4% and sensitivity at 87.3%. The best diagnosing cut-off value of III PM was AHI=15.70, at this point, the maximum Youden's index was obtained as 0.695. Conclusion: Using AHI≥15 as standard, III PM and II PSG had the favorable consistency and accuracy for monitoring the severity of SA for in-hospital patients with cardiovascular disease. AHI=15.7 was the best cut-off point of III PM in diagnosing moderate and severe SA in relevant patients.
ABSTRACT
Objective To investigate the relationship between the neuroprotective effect of epigallocatechin gallate ( EGCG ) for PC12 cells induced by 1-methyl-4-phenyl-pyridinium ( MPP+ ) and activating nuclear factor-related factor 2 ( NRF2 ).Methods Well differentiated PC12 cells treated with MPP+ were used as the in vitro cell models,and PC12 cells were pretreated with different concentrations of EGCG.MTT assay was used to investigate the cell viability.Western blot was used to observe the expression of NRF2 in cells and distribution in the nucleus and the cytoplasm.Real-time PCR was used to observe the antioxidant enzymes,HO-1 and NQO1 mRNA expression.Results Pretreatment of PC12 cells with different concentrations of EG CG for an hour could restore cell viability.Western blot showed that expression of NRF2 in cells treated with MPP+ for 24 hours was increased 148％ +5％ compared with the control group (t =6.102,P ＜0.01 ).The level of NRF2 in EGCG pretreated group was 188％ + 6％ compared with the control group(t =11.172,P ＜0.01 ).Moreover the NRF2 protein level in the nuclear was also increased.Western blot showed that the NRF2 protein level in the nuclear was 258％ +2％ compared with the control group (t =21.995,P ＜ 0.01 ).Further research found U 120,an inhibitor of ERK,could inhibit the effect of EGCG.The levels of NRF2 in both samples were 148％ ± 15％ and 158％ ± 1％ compared with their respective control groups(t =6.118,8.058,both P ＜0.01 ).In accordance with the NRF2 data,real-time PCR indicated that the levels of HO-1 and NQO1 mRNA expression increased obviously in the group pretreated with EGCG.Likewise,U120 could also inhibit HO-1 and NQO1 mRNA expression induced by EGCG.Conclusions EGCG can repair oxidative damage to PC12 cells induced by MPP+.The protective effect may be related through the ways to activate ERK-NRF2 and induce downstream of antioxidant enzyme expression,such as HO-1 and NQO1.