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It is generally well-known that smoking has a substantial impact on general health, and cardiovascular health in particular. The purpose of this study was to analyze the effects of different smoking status on the burden and characteristics of coronary artery plaques in Chinese men.Our study enrolled 1920 individuals with suspected coronary artery disease undergoing 256-detector-row computed tomography scan after clinical assessment. These study participants were stratified into three groups: never smoker, current smoker, and former smoker, according to their smoking status. Thereafter, the associations of different smoking status with the coronary artery plaques were assessed using both univariable and multivariable logistic regression.The prevalences of any plaque, significant stenosis and coronary artery calcium score (CACS) ≥ 10 were highest in the current smokers (all p0.05). The proportion of calcified plaques was the lowest and the prevalence of non-calcified plaques was the highest in current smokers (p = 0.004). The higher pack-years group had significantly elevated percentages of any plaque, significant stenosis, ≥ 2/LM vessel disease and CACS ≥ 10 than the lower pack-years group (all p0.001). The percent of calcified plaques was lower and the percent of non-calcified plaques was higher in the higher (20) pack-years group than in the lower pack-years group (≤ 20) (p = 0.024). Current smoking with higher pack-years was the independent risk factor for any plaque, significant stenosis, CACS ≥ 10, non-calcified and mixed plaques (all p0.05) after multivariate adjustments.The current smokers had the most serious burden of coronary artery plaques and the highest percentage of non-calcified plaques. Current smoking with higher pack-years was a significant risk factor for coronary artery plaque burden and non-calcified and mixed plaques.Chinese men; Cigarette smoking; Coronary artery calcium score; Coronary artery plaques; Non-calcified plaques.

Background Many patients who survive a myocardial infarction (MI) remain at risk of sudden cardiac death despite revascularization and optimal medical treatment. We used the modified moving average (MMA) method to assess the utility of T-wave alternans (TWA) and heart rate turbulence (HRT) as risk markers in MI patients with or without diabetes mellitus (DM). Methods We prospectively enrolled 248 consecutive patients: 96 with MI (post-MI patients); 77 MI with DM (post-MI + DM patients); 75 controls without cardiovascular disease (group control). Both TWA and HRT were measured on ambulatory electrocardiograms (AECGs). HRT was assessed by two parameters ─ turbulence onset (TO) and turbulence slope (TS). HRT was considered positive when both TO ≥0% and TS ≤2.5 ms/R-R interval were met. The endpoint was cardiac mortality. Results TWA values differed significantly between MI and controls. Post-MI + DM patients had higher TWA values than post-MI patients (58 ± 21 μV VS 52 ± 18 μV, P = 0.029). Impaired HRT--increased TO and decreased TS were observed in MI patients with or without DM. During follow-up of 578 ± 146 days, cardiac death occurred in ten patients and three of them suffered sudden cardiac death (SCD). Multivariate analysis determined that a HRT-positive outcome [HR (95% CI): 5.01, 1.33–18.85; P = 0.017], as well as the combination of abnormal TWA (≥47 μV) and positive HRT had significant association with the endpoint [HR (95% CI): 9.08, 2.21–37.2; P = 0.002)]. Conclusion This study indicates that AECGs-based TWA and HRT can predict cardiac mortality in MI patients with or without DM. Combined analysis TWA and HRT may be a convenient and useful method of identifying patients at high risk for cardiovascular death.

Approach to mechanism of hypoxia-induced factor 1alpha expression in endothelial cells of human umbilical vein and its induction of apoptosisIn vitro models, and such techniques as transmission electron microscopy, flow cytometry, RT-PCR and Western blot, were applied to investigate the transcription and protein expression of HIF-1alpha mRNA in ECV 304 cells and the action of HIF-1alpha on cell cycle blocking, proliferation inhibition and induction of apoptosis. Cells were divided into two groups: normal oxygen and hypoxic for various time periods (2, 4, 8, 12, 24 and 48 h).We observed that the expression level of HIF-1alpha mRNA and its protein were correlated with the degree of hypoxia. The expression of HIF-1alpha mRNA notably increased after 4, 8, 12, 24 and 48 h of hypoxia, particularly at 24 and 48 h with a gray scale of (71 +/- 1.81) and (70 +/- 2.02) respectively, differing significantly from the control group (P0.01), The protein expression of HIF-1alpha also increased 4, 8, 12, 24 and 48 h after hypoxia, particularly at 24 and 48 h, with gray scale (83 +/- 0.15) and (98 +/- 0.10) respectively (P0.01), indicating an increase of HIF-1alpha protein expression significantly different from the other groups (P0.01). In the control group, there was slight transcription and protein expression of HIF-1alpha at 0 h after hypoxia. Meanwhile, each phase of the cell cycle was detected to have increased expression of HIF-1alpha in response to oxygen-deficient treatment. At times of 24 and 48 h, the number percentage of cells in G1 significantly increased with values of 66.335 +/- 2.144 and 58.890 +/- 5.128; however, the number cells in S phase decreased to 36.215 +/- 1.582 and 39.826 +/- 5.097, significantly different compared to the control group at 0 h with values of 43.903 +/- 6.506 and 60.571 +/- 24.026-(P0.05). When the cell cycle was blocked in the G2/S phase, the cell apoptosis ratio significantly increased by 9.24 +/- 1.828 and 30.735 +/- 11.38, compared to each control group-(P0.01).By induction of hypoxia, the cell cycle was dramatically blocked in G1/S phase, and the expression of HIF-1alpha also increased Therefore, sustained expression of HIF-1alpha can inhibit cell hyperplasia, and the apoptosis promotion of injured cells as well as provide protection of endothelial cells.

Aims To investigate different ways of isolating and culturing rat MSC and different serum concentrations of medium for the best selection. Materials and methods Direct adherence and density gradient centrifugation methods are used in MSC isolation, routine and modicum medium change methods are used in MSC culture. We compared the growth state, cell quantity and population doubling time of MSC under different culturing ways and different serum concentration medium such as 10%, 11% and 15%. We identified cultured MSC in logarithmic growth phase (P3 generation) by cell surface antigen and its inducing differentiation function. Results 4 methods, which are direct adherent and routinely changing of medium method, direct adherent and modicum medium changing method, density gradient centrifugation and routinely changing of medium method and density gradient centrifugation and modicum medium changing method, are used during MSC isolating and culturing respectively. The cellular average doubling time is 36.0±0.9 h, 23.5±1.1 h, 49.8±12 h and 48.0±0.8 h respectively There are cellular colonies forming 3 to 10 days after isolation, shaping like whirlpool. From the serum concentration screening experiment, we find that 11% is the most suitable one for MSC growth. The result of cell surface antigen identification of MSC through immunol histochemistry is CD45 (−), CD90 (+), and CD45 0.38%, CD90 98.4% for positive expression of MSC through flow cytometry. MSC can be successfully induced to differentiate to chondrocyte and lipocyte. Conclusions Direct adherent and modicum medium changing method is the best one for MSC isolation and culture. 11% is the most suitable serum concentration for MSC growth.