ABSTRACT
Objective To investigate the blood pressure variability(BPV) and circadian rhythms in young and middle-aged people with H-type hypertension.Methods The ambulatory blood pressure monitoring data from 89 young and middle-aged patients with mild-to-moderate hypertension were retrospectively analyzed.All cases were divided into the H-type hypertension group (n=56) and non-H-type hypertension group(n=33) according to plasma homocysteine(Hcy) level.Blood pressure in different time periods(including 24hSBP/24hDBP,dSBP/dDBP,nSBP/nDBP,mSBP/mDBP,mnSBP/mnDBP),variability(including 24hSBPV/24hDBPV,dSBPV/dDBPV,nSBPV/nDBPV,mSBPV/mDBPV,mnSBPV/mnDBPV),day and night average heart rate,dipper ratio of SBP/DBP and morning blood pressure surge were compared between the two group.Results 24hSBP,dSBP,nSBP and mSBP in the H-type hypertension group were significantly higher than those in the non-H-type hypertension group,while 24hDBP,dDBP,nDBP and mDBP were significantly lower than those in the non-H-type group,the differences were statistically significant(P＜0.01).24hSBPV,24hDBPV,dSBPV,nDBPV and mSBPV had statistically significantly difference between the H-type hypertension group and non-H-type hypertension group(P＜0.05).The dipper ratio of SBP and mean MBPS in the H-type hypertension group were significantly higher than those in the non-H-type hypertension group(P＜0.01).Conclusion Blood pressure variability is increased within a certain range in young and middle-aged patients with H-type hypertension,which is correlated to circadian rhythm changes.
ABSTRACT
BACKGROUND:The mechanisms of mesenchymal stem cells directional y homing to infarcted myocardium post myocardial infarction are stil unclear. OBJECTIVE:To investigate the role of stromal cellderived factor-1 (SDF-1)/C-X-C chemokine receptor 4 (CXCR4) axis on mesenchymal stem cellmigration promoted by mononuclear cells after myocardial infarction. METHODS:Cardiomyocytes and mesenchymal stem cells were respectively isolated from suckling and adult Sprague-Dawley rats. Twelve healthy Sprague-Dawley rats were selected (six rats for myocardial infarction models and six for sham models), then circulating mononuclear cells were isolated. 4,6-Diamino-2-phenyl indole-labeled mesenchymal stem cells, cardiomyocytes and mononuclear cells were cultured into the upper, middle and lower layers of the tri-chamber coculture system, respectively. In this experiment, there were four groups:myocardial infarction group, AMD3100 (CXCR4 inhibitor) group, sham group and blank control group. After 48 hours, the number of migrating mesenchymal stem cells with blue-lighting nucleus was calculated under fluoroscope. Immunocytochemistry and immunofluorescent staining was used to detect SDF-1 expression in cardiomyocytes and CXCR4 expression in mesenchymal stem cells, respectively. RESULTS AND CONCLUSION:Migrating mesenchymal stem cells with positive expression of CXCR4 were observed in each group other than the blank control group. The number of migrating mesenchymal stem cells was higher in the myocardial infarction group than in the other groups. Tumor necrosis factor-αneutralizing antibody and CXCR4 inhibitor AMD3100 could obviously reduce the number of migrating mesenchymal stem cells (P<0.05). Cardiomyocytes in each group expressed SDF-1 positively. The gray values of SDF-1 expression in the myocardial infarction and AMD3100 groups were significantly higher than those in the sham and blank control groups (P<0.05). SDF-1/CXCR4 axis plays a certain role in mesenchymal stem cells migration promoted by mononuclear cells after myocardial infarction.