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The macromolecular organization in system composed of anionic poly(acrylic acid) (PAA) and cationic chitosan (Cs), with different degrees of deacetylation (DD), under extensive elongational flow, is described. Cs/PAA nanofibers were obtained, and polyelectrolyte complexation only occurred when fibers were immersed in fluid media of a certain pH. Assembled polyelectrolytes complexes formed a pH-triggered system, as demonstrated by reversible change of the swelling degree, by 3 orders of magnitude, and a change on the elastic modulus, by 2 orders of magnitude. Both the swelling degree and the elastic modulus proved sensitive to the DD of Cs. Rheological measurements showed that increased DD of Cs resulted in a decrease in viscosity of both pure Cs and precursor Cs/PAA solutions, attributed to repulsive interactions between ionized amino groups in Cs. At the same time, a DD-dependent change in balance between hydrogen bonding and ion-dipole interactions between the components in Cs/PAA, was responsible for the more pronounced viscosity decrease in these solutions. [ABSTRACT FROM AUTHOR]

Objective: The RIFT study aimed to observe the impact of renal insufficiency (RI) on the incidence of stent thrombosis (ST) after percutaneous coronary intervention. Methods: The RIFT study enrolled 1,174 patients undergoing revascularization exclusively with sirolimus-eluting stents. The occurrence of ST and major adverse cardiac events were compared between patients with (n = 309) and without (n = 865) RI, and independent predictors of ST were also identified. Results: During follow-up (mean 18.9 ± 9.2 months), the rate of ST was significantly higher in patients with than without RI [5.5% (n = 17) vs. 1.7% (n = 15), p < 0.001], and the presence of severe RI (estimated glomerular filtration rate <30 ml/min·1.73 m2) was an independent predictor of ST (odds ratio = 4.5, 95% confidence interval 1.4–15, p = 0.011). In patients with RI and diabetes or left ventricular ejection fraction (LVEF) <50%, the incidence of ST was significantly increased [13.0% (n = 10) vs. 3.6% (n = 7), p = 0.010; 11.6% (n = 8) vs. 1.9% (n = 3), p = 0.004, respectively] compared to those with diabetes or LVEF <50% alone. The influence of RI on ST was not significant in patients with multivessel disease, calcified or bifurcation lesions, and target lesion revascularization. Conclusions: These findings substantiate the importance of long-term antiplatelet therapy for patients with RI after drug-eluting stent implantation. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

OBJECTIVE--To investigate whether glycation level of apoprotein (apo)A-I is associated with coronary artery disease (CAD) and plaque progression in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS--Among 375 consecutive type 2 diabetic patients undergoing quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS), 82 patients with nonsignificant stenosis (luminal diameter narrowing ,30% [group I]) and 190 patients with significant CAD (luminal diameter stenosis ≥70% [group II]) were included for analysis of apoA-I glycation level and serum activity of lecithin: cholesterol acyltransferase (LCAT). The control group had 136 healthy subjects. At the 1-year follow-up, angiography and IVUS were repeated mainly in group II patients for plaque progression assessment. RESULTS--Relative intensity of apoA-I glycation by densitometry was increased, and serum LCAT activity was decreased stepwise across groups control, I, and II. These two measurements were associated with the number of diseased coronary arteries and extent index in group II. During 1-year follow-up, QCA detected 45 patients with plaque progression in 159 subjects, and IVUS found 38 patients with plaque progression in 127 subjects. Baseline relative intensity of apoA-I glycation was significantly increased in patients with plaque progression compared with those without, with values associated with changes in QCA and IVUS measurements. Multivariable regression analysis revealed that baseline relative intensity of apoA-I glycation was an independent determinant of CAD and plaque progression in type 2 diabetic patients. CONCLUSIONS--ApoA-I glycation level is associated with the severity of CAD and coronary artery plaque progression in type 2 diabetic patients. [ABSTRACT FROM AUTHOR]

Background: Drug-eluting stents (DES) constitute a major breakthrough in restenosis prevention after percutaneous coronary intervention (PCI). This study compared the clinical outcomes of PCI using DES versus coronary artery bypass graft (CABG) in patients with multivessel coronary artery disease (MVD) in real-world. Methods: From January 2003 to December 2004, 466 consecutive patients with MVD underwent revascularization, 235 by PCI with DES and 231 by CABG. The study end-point was the incidence of major adverse cardiovascular events (MACEs) at the first 30 days after procedure and during follow-up. Results: Most preoperative characteristics were similar in the two groups, but left main disease (24.7% vs 2.6%, P<0.001) and three-vessel disease (65% vs 54%, P = 0.02) were more prevalent in CABG group. The number of coronary lesions was also greater in CABG group (3.7 ± 1.1 vs 3.3 ± 1.1, P<0.001). Despite higher early morbidity (3.9% vs 0.8%, P = 0.03) associated with CABG, there were no significant differences in composite MACEs at the first 30 days between the two groups. During follow-up (mean 25±8 months), the incidence of death, myocardial infarction, or cerebrovascular event was similar in both groups (PCI 6.3% vs CABG 5.6%, P = 0.84). However, bypass surgery still afforded a lower need for repeat revascularization (2.8% vs 10.4%, p = 0.001). Consequently, overall MACE rate (14.5% vs 7.9%, P = 0.03) remained higher after PCI. Conclusion: PCI with DES is a safe and feasible alternative to CABG for selected patients with MVD. The reintervention gap was further narrowed in the era of DES. Aside from restenosis, progression of disease needs to receive substantial emphasis. [ABSTRACT FROM AUTHOR]

High-mobility group box (HMGB) family is related to inflammatory diseases. We investigated whether serum HMGB2 levels are related to myocardial infarction (MI) severity and major adverse cardiac events (MACE) during MI. We included 432 consecutive patients with ST-segment elevation myocardial infarction and 312 controls. Serum HMGB2 levels were significantly higher in MI patients than in controls. Increased HMGB2 levels were associated with MACE and negatively with ejection fraction in MI patients. HMGB2 was an independent determinant of MACE in logistic regression analysis. HMGB2 protein (10 μg) or saline was injected intramyocardially in MI rats, with or without coadministration of the NADPH oxidase inhibitor apocynin. After 72 h, pathological, echocardiographic, and hemodynamic examinations showed that HMGB2 increased infarct size and worsened cardiac function in MI rats. Moreover, HMGB2 administration enhanced reactive oxygen species (ROS) production, cell apoptosis, inflammation, and autophagosome clearance impairment, which were attenuated by coadministration of apocynin or knock down of receptor for advanced glycation end products (RAGE). In conclusion, increased serum HMGB2 levels are associated with MI severity and MACE at 1 mo. HMGB2 promotes myocardial ischemic injury in rats and hypoxic H9C2 cell damage via ROS provoked by RAGE. [ABSTRACT FROM AUTHOR]

It is thought that carbamylated modification plays a crucial role in the development and progression of cardiovascular disease (CVD) in patients with end-stage renal disease (ESRD). However, information on the biological effects of carbamylated high-density lipoprotein (C-HDL) in ESRD is poor. The present study investigated the carbamylation level of HDL in ESRD and the effects of C-HDL on endothelial repair properties. HDL was isolated from healthy control subjects (n = 22) and patients with ESRD (n = 30). The carbamylation level of HDL was detected using ELISA. Isolated C-HDL for use in tissue culture experiments was carbamylated in vitro to a similar extent to that observed in ESRD. Human arterial endothelial cells were treated with C-HDL or native HDL to assess their migration, proliferation, and angiogenesis properties. HDL-associated paraoxonase 1 activity was also determined by spectrophotometry assay. Compared with healthy control subjects, the carbamylation level of HDL in ESRD patients was increased and positively correlated with blood urea concentration. In vitro, C-HDL significantly inhibited migration, angiogenesis, and proliferation in endothelial cells. Mechanistic studies revealed that HDL-associated paraoxonase 1 activity was decreased and negatively correlated with the carbamylation level of HDL in ESRD patients. In addition, C-HDL suppressed the expression of VEGF receptor 2 and scavenger receptor class B type I signaling pathways in endothelial cells. In conclusion, the present study identified a significantly increased carbamylation level of HDL in ESRD. Furthermore, C-HDL inhibited endothelial cell repair functions. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether apolipoprotein A (apoA)-I glycation and paraoxonase (PON) activities are associated with the severity of coronary artery disease (CAD) in patients with type 2 diabetes mellitus (T2DM). Methods: Relative intensity of apoA-I glycation and activities of high-density lipoprotein (HDL)-associated PON1 and PON3 were determined in 205 consecutive T2DM patients with stable angina with (n = 144) or without (n = 61) significant CAD (luminal diameter stenosis ≥ 70 %). The severity of CAD was expressed by number of diseased coronary arteries, extent index, and cumulative coronary stenosis score (CCSS). Results: The relative intensity of apoA-I glycation was higher but the activities of HDL-associated PON1 and PON3 were lower in diabetic patients with significant CAD than in those without. The relative intensity of apoA-I glycation increased but the activities of HDL-associated PON1 and PON3 decreased stepwise from 1 - to 3 - vessel disease patients (P for trend < 0.001). After adjusting for possible confounding variables, the relative intensity of apoA-I glycation correlated positively, while the activities of HDL-associated PON1 and PON3 negatively, with extent index and CCSS, respectively. At high level of apoA-I glycation (8.70 ~ 12.50 %), low tertile of HDL-associated PON1 (7.03 ~ 38.97U/mL) and PON3 activities (7.11 ~ 22.30U/mL) was associated with a 1.97- and 2.49- fold increase of extent index and 1.73- and 2.68- fold increase of CCSS compared with high tertile of HDL-associated PON1 (57.85 ~ 154.82U/mL) and PON3 activities (39.63 ~ 124.10U/mL), respectively (all P < 0.01). Conclusions: Elevated apoA-I glycation and decreased activities of HDL-associated PON1 and PON3, and their interaction are associated with the presence and severity of CAD in patients with T2DM. [ABSTRACT FROM AUTHOR]

Background We investigated whether serum glycated albumin (GA) levels are related to coronary collateralization in type 2 diabetic patients with chronic total occlusion. Methods Blood levels of GA and glycosylated hemoglobin (HbA1c) were determined in 317 diabetic and 117 non-diabetic patients with stable angina and angiographic total occlusion of at least one major coronary artery. The degree of collaterals supplying the distal aspect of a total occlusion from the contra-lateral vessel were graded as low (Rentrop score of 0 or 1) or high collateralization (Rentrop score of 2 or 3). Results For diabetic patients, GA (21.2 ± 6.5% vs. 18.7 ± 5.6%, P < 0.001) but not HbA1c levels (7.0 ± 1.1% vs. 6.8 ± 1.3%, P = 0.27) was significantly elevated in low collateralization than in high collateralization group, and correlated inversely with Rentrop score (Spearmen's r = -0.28, P < 0.001; Spearmen's r = -0.10, P = 0.09, respectively). There was a trend towards a larger area under the curve of GA compared with that of HbA1c for detecting the presence of low collateralization (0.64 vs. 0.58, P = 0.15). In non-diabetic patients, both GA and HbA1c levels did not significantly differ regardless the status of coronary collateralization. In multivariable analysis, female gender, age > 65 years, smoke, non-hypertension, duration of diabetes > 10 years, metabolic syndrome, eGFR < 90 ml/min/1.73 m2, and GA > 18.3% were independently determinants for low collateralization in diabetic patients. Conclusions Increased GA levels in serum are associated with impaired collateral growth in type 2 diabetic patients with stable angina and chronic total occlusion. [ABSTRACT FROM AUTHOR]

Background: Non-enzymatic glycation increases hemoglobin-oxygen affinity and reduces oxygen delivery to tissues by altering the structure and function of hemoglobin. Objectives: We investigated whether an elevated blood concentration of glycosylated hemoglobin (HbA1c) could induce falsely high pulse oximeter oxygen saturation (SpO2) in type 2 diabetic patients during mechanical ventilation or oxygen therapy. Methods: Arterial oxygen saturation (SaO2) and partial pressure of oxygen (PO2) were determined with simultaneous monitoring of SpO2 in 261 type 2 diabetic patients during ventilation or oxygen inhalation. Results: Blood concentration of HbA1c was >7% in 114 patients and ≤ 7% in 147 patients. Both SaO2 (96.2 ± 2.9%, 95% confidence interval [CI] 95.7-96.7% vs. 95.1 ± 2.8%, 95% CI 94.7-95.6%) and SpO2 (98.0 ± 2.6%, 95% CI 97.6-98.5% vs. 95.3 ± 2.8%, 95% CI 94.9-95.8%) were significantly higher in patients with HbA1c >7% than in those with HbA1c ≤ 7% (Data are mean ± SD, all p < 0.01), but PO2 did not significantly differ between the two groups. Bland-Altman analysis demonstrated a significant bias between SpO2 and SaO2 (1.83 ±0.55%, 95% CI 1.73% -1.94%) and limits of agreement (0.76% and 2.92%) in patients with HbA1c >7%. The differences between SpO2 and SaO2 correlated closely with blood HbA1c levels (Pearson's r = 0.307, p < 0.01). Conclusions: Elevated blood HbA1c levels lead to an overestimation of SaO2 by SpO2, suggesting that arterial blood gas analysis may be needed for type 2 diabetic patients with poor glycemic control during the treatment of hypoxemia. [ABSTRACT FROM AUTHOR]

Background: rs1333049 polymorphism on chromosome 9p21 has been shown to affect susceptibility to coronary artery disease (CAD) in Caucasians. This study examined the association of rs1333049 with myocardial infarction (MI), angiographic severity of CAD and clinical outcome after a first acute MI in Han Chinese. Methods: rs1333049 polymorphism was genotyped in 520 patients with a first acute MI and in 560 controls. The number of angiographically documented diseased coronary arteries (luminal diameter stenosis ≥50%), echocardiographic left ventricular ejection fraction (LVEF), and major adverse cardiac events (MACE) during follow-up (mean, 29±15 months) were recorded. Results: Patients with MI had higher frequencies of the CC genotype (30.0% vs. 20.7%) or C allele (55.5% vs. 46.2%) compared with controls (all p<0.01). rs1333049 polymorphism was strongly associated with MI [odds ratio (OR) 1.48, 95% confidence interval (CI) 1.22–1.79] after adjusting for traditional risk factors. Although longer hospitalization stay was observed in patients with the rs1333049- C allele, this polymorphism was not related to angiographic severity of CAD, LVEF, and occurrence of MACE after MI. Conclusions: This study demonstrates an association of rs1333049 polymorphism locus on chromosome 9p21 with risk for MI, but not with post-MI prognosis in Han Chinese. Clin Chem Lab Med 2009;47:917–22. [ABSTRACT FROM AUTHOR]

Background: Coronary artery disease (CAD) is a major vascular complication of diabetes mellitus and reveals high mortality. Up to 30% of diabetic patients with myocardial ischemia remain asymptomatic and are associated with worse prognosis compared to non-diabetic counterpart, which warrants routine screening for CAD in diabetic population. The purpose of this study was to evaluate the clinical value of serum glycated albumin and high-sensitivity C-reactive protein (hs-CRP) levels in predicting the presence of CAD in patients with type 2 diabetes. Methods: Three hundred and twenty-four patients with type 2 diabetes were divided into two groups based on presence (CAD group, n = 241) or absence (control group, n = 83) of angiographically-documented CAD (lumen diameter narrowing =70%). Serum levels of glycated albumin and hs-CRP as well as serum concentrations of glucose, lipids, creatinine, blood urea nitrogen and uric acid were measured in both groups. Predictors of CAD were determined using multivariate logistic regression model and receiver-operating characteristic (ROC) curves. Results: Serum glycated albumin and hs-CRP levels were significantly increased in diabetic patients with CAD. Multivariate regression analysis revealed that male gender, age, serum levels of glycated albumin, hs-CRP, creatinine and lipoprotein (a) were independent predictors for CAD. Areas under the curve of glycated albumin and hs-CRP and for regression model were 0.654 (95%CI 0.579-0.730, P < 0.001), 0.721 (95%CI 0.658-0.785, P < 0.001) and 0.824 (95% CI 0.768-0.879, P < 0.001), respectively. The optimal values of cut-off point were 18.7% (sensitivity 67.9%, specificity 60.0%) for glycated albumin and 5.2 mg/l (sensitivity 72.2%, specificity 60.0%) for hs-CRP to predict CAD. Logistic regression model was defined as: P/(1-P) = EXP(-1.5 + 1.265 gender + 0.812 age + 1.24 glycated albumin + 0.953 hs-CRP + 0.902 lipoprotein(a) + 1.918 creatinine). The optimal probability value for predicting CAD in type 2 diabetic patients was 0.648 (sensitivity 82.3%, specificity 68.6%). Conclusion: Serum glycated albumin and hs-CRP levels were significantly elevated in patients with type 2 diabetes and CAD. The logistic regression model incorporating with glycated albumin, hs-CRP and other major risk factors of atherosclerosis may be useful for screening CAD in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]