RESUMO
Objective To investigate the effects of insulin-like growth factor-1 (IGF-1) and oxidized low density lipoprotein (oxLDL) on expression of phosphatase PHLPP1 in vascular smooth muscle cells (VSMCs).Methods Rabbit aortic VSMCs were cultured.VSMCs proliferation ability was determined by measuring cell number and mitochondrial dehydrogenase (MD) activity with MTT assay.Western blot was used to detect the protein expression of phosphatase PHLPP 1.Results IGF-1 (100μg/L) increased cell number and MD activity to 3.02 and 3.59 times of that in control group.oxLDL(50μg/ ml) elevated the above two parameters to 2.03 and 2.91 times respectively.Western blot showed that IGF-1 and oxLDL inhibited the expression of PHLPP 1 to 39.27% and 40.26% of the control group (P＜0.01).Conclusion IGF-1 and oxLDL may enhance the proliferation of VSMCs by decreasing the expression of phosphatase PHLPP1 .
RESUMO
Objective To evaluate the feasibility and efficacy of intravascular optical coherence tomography (OCT) in the assessment of plaque characteristics and drug eluting stent deployment quality in the elderly patients with unstable angina (UA) and non-ST segment elevation myocardial infarction (NSTEMI). Methods OCT was used in elderly patients undergoing percutaneous coronary interventions.Fifteen patients, 9 males and 6 females with mean age of 72.6±5.3 years (range 67-92 years) were enrolled in the study. Images were obtained before initial balloon dilatation and following stent deployment. The plaque characteristics before dilation, vessel dissection,tissue prolapse, stent apposition and strut distribution after stent implantation were evaluated. Results Fifteen lesions were selected from 32 angiographic lesions as study lesions for OCT imaging after diagnostic coronary angiography. There were 7 lesions in the left anterior descending artery, 5 lesions in the right coronary artery and 3 lesions in the left circumflex coronary artery. Among them,12 (80.0%) were lipid-rich plaques, and 10 (66.7%) were vulnerable plaques with fibrous cap thickness 54.2±7.3 μm. Seven ruptured culprit plaques (46.7%) were found; 4 in UA patients and 3 in NSTEMI patients. Tissue prolapse was observed in 11 lesions (73.3%).Irregular stent strut distribution was detected in 8 lesions (53.3%). Vessel dissections were found in 5 lesions (33.3%). Incomplete stent apposition was observed in 3 stents (20%) with mean spacing between the struts and the vessel wall 172±96 mm (range 117-436 mm).Conclusions 1) It is safe and feasible to perform intravascular OCT to differentiate vulnerable coronary plaque and monitor stent deployment in elderly patients with UA and USTEMI. 2) Coronary plaques in elderly patients with UA and USTEMI could be divided into acute ruptured plaque, vulnerable plaque, lipid-rich plaque, and stable plaque. 3) Minor or critical plaque rupture is one of the mechanisms of UA in elderly patients. 4) Present drug eluting stent implantation is complicated with multiple tissue prolapses which are associated with irregular strut distributions. 5) The action and significance of tissue prolapse on acute vessel flow and in-stent thrombus and restenosis need to be further studied.
RESUMO
Background and objective To assess the predictive value of C-reactive protein(CRP) for major adverse cardiac events and the association between CRP level and the coronary lesion morphology and extent in patients with coronary heart disease (CHD).Methods CRP was measured on admission in 177 consecutive elderly (age≥60 years) patients with CHD who underwent coronary angiography. Patients were divided into high CRP group (CRP≥3mg/L) and normal CRP group (CRP ＜3mg/L). The association between CRP levels and the coronary lesion features, including severity of stenosis (mild, moderate, severe), extent of lesion (diffused or nondiffused), eccentricity of the plaque (eccentric or non-eccentric) were analyzed. Patients were followed up for a mean of 8 months for the occurrences of major adverse cardiac events (MACE). Results Compared with patients in normal CRP group, patients in high CRP group were more frequently to have unstable angina, multi-vessel, diffuse, eccentric lesions, positive remodeling, and non-smooth plaques (P＜0.01). Kaplan-Meier analysis showed patients in high CRP group had a significantly lower MACE-free survival rate than patients in normal CRP group (Log-rank = 12.0, P＜0.01); Cox regression analysis indicated CRP level as an independent predictor for the occurrence of MACE (OR=3.16, P＜0.05) Conclusions High CRP level is associated with more extend, severe and eccentric coronary lesions and is an independent predictor for MACE in elderly patients with CHD.