ObjectivesIncreased plasma C-reactive protein (CRP) levels are associated with the occurrence and severity of acute coronary syndrome. We investigated whether CRP can be generated in vascular endothelial cells (ECs) after exposure to the most electronegative subfraction of low-density lipoprotein (LDL), L5, which is atherogenic to ECs. Because L5 and CRP are both ligands for the lectin-like oxidized LDL receptor-1 (LOX-1), we also examined the role of LOX-1.Methods and ResultsPlasma LDL samples isolated from asymptomatic hypercholesterolemic (LDL cholesterol [LDL-C] levels, 154.6±20 mg/dL; n = 7) patients and normocholesterolemic (LDL-C levels, 86.1±21 mg/dL; P<0.001; n = 7) control individuals were chromatographically resolved into 5 subfractions, L1-L5. The L5 percentage (L5%) and the plasma L5 concentration ([L5]  =  L5% × LDL-C) in the patient and control groups were 8.1±2% vs. 2.3±1% (P<0.001) and 12.6±4 mg/dL vs. 1.9±1 mg/dL (P<0.001), respectively. In hypercholesterolemic patients treated with atorvastatin for 6 months (10 mg/day), [L5] decreased from 12.6±4 mg/dL to 4.5±1.1 mg/dL (P = 0.011; n = 5), whereas both [L5] and L5% returned to baseline levels in 2 noncompliant patients 3 months after discontinuation. In cultured human aortic ECs (HAECs), L5 upregulated CRP expression in a dose- and time-dependent manner up to 2.5-fold (P<0.01), whereas the least electronegative subfraction, L1, had no effect. DiI-labeled L1, internalized through the LDL receptor, became visible inside HAECs within 30 seconds. In contrast, DiI-labeled L5, internalized through LOX-1, became apparent after 5 minutes. L5-induced CRP expression manifested at 30 minutes and was attenuated by neutralizing LOX-1. After 30 minutes, L5 but not L1 induced reactive oxygen species (ROS) production. Both L5-induced ROS and CRP production were attenuated by ROS inhibitor N-acetyl cysteine.ConclusionsOur results suggest that CRP, L5, and LOX-1 form a cyclic mechanism in atherogenesis and that reducing plasma L5 levels with atorvastatin disrupts the vascular toxicity of L5.

OBJECTIVES:To compare the satisfaction and knowledge of patients who have their warfarin managed by their physician or by a multidisciplinary, telephone-based anticoagulation service (ACS) and to assess referring physicians' satisfaction with the ACS. DESIGN AND PARTICIPANTS:We surveyed 300 patients taking warfarin (mean age 73 years): 150 at health centers randomized to have access to an ACS, and 150 at control health centers without ACS access. We also surveyed 17 physicians who refer patients to the ACS. SETTING:Eight outpatient health centers in Missouri and Southern Illinois. MEASUREMENTS:We asked patients about the timeliness of international normalized ratio (INR) monitoring, perceived safety of warfarin, overall satisfaction with their warfarin management, and knowledge of what a high INR meant. We asked physicians at ACS-available health centers how many minutes they saved per INR by referring patients to the ACS, their satisfaction with the ACS, and their willingness to recommend the ACS to a colleague. MAIN RESULTS:As compared with patients at control health centers, patients at ACS-available health centers were more satisfied with the timeliness of getting blood test results (mean 4.31 vs 4.03, P = .02), were more likely to know what a safe INR value was (45% vs 15%, P = .001), and felt safer taking warfarin (mean 5.7 vs 5.2, P = .04). Physicians reported that using the ACS saved, on average, four minutes of their time and 13 minutes of their staff's time, per INR. All physicians recommended use of the ACS to a colleague and were highly satisfied with the ACS. CONCLUSIONS:A telephone-based ACS can be endorsed by primary-care physicians and improve patients' satisfaction with and knowledge about their antithrombotic therapy.

Liposomes have been used to diagnose and treat cancer and, to a lesser extent, cardiovascular disease. We previously showed the uptake of anionic liposomes into the atheromas of Watanabe heritable hyperlipidemic rabbits within lipid pools. However, the cellular distribution of anionic liposomes in atherosclerotic plaque remains undescribed. In addition, how anionic liposomes are absorbed into atherosclerotic plaque is unclear. We investigated the uptake and distribution of anionic liposomes in atherosclerotic plaque in aortic tissues from apolipoprotein E-deficient (ApoE−/−) mice. To facilitate the tracking of liposomes, we used liposomes containing fluorescently labeled non-silencing small interfering RNA. Confocal microscopy analysis showed the uptake of anionic liposomes into atherosclerotic plaque and colocalization with macrophages. Transmission electron microscopy analysis revealed anionic liposomal accumulation in macrophages. To investigate how anionic liposomes cross the local endothelial barrier, we examined the role of clathrin-mediated endocytosis in human coronary artery endothelial cells (HCAECs) treated with or without the inflammatory cytokine tumor necrosis factor (TNF)-α. Pretreatment with amantadine, an inhibitor of clathrin-mediated endocytosis, significantly decreased liposomal uptake in HCAECs treated with or without TNF-α by 77% and 46%, respectively. Immunoblot analysis showed that endogenous clathrin expression was significantly increased in HCAECs stimulated with TNF-α but was inhibited by amantadine. These studies indicated that clathrin-mediated endocytosis is partly responsible for the uptake of liposomes by endothelial cells. Our results suggest that anionic liposomes target macrophage-rich areas of vulnerable plaque in ApoE−/− mice; this finding may lead to the development of novel diagnostic and therapeutic strategies for treating vulnerable plaque in humans.

Hypoplastic aortoiliac syndrome (HAIS) occurs in young women and is characterized by a small infrarenal aorta with a hypoplastic iliofemoral arterial system and advanced atherosclerotic disease. Of 304 aortoiliac interventions (AoI), 30 female patients (mean age, 50 +/- 5 years) had HAIS. HAIS patients were less likely to have coronary disease (33% vs. 88%; P < 0.0001) or diabetes (10% vs. 42%; P < 0.001) compared to their AoI counterparts. Twenty-three patients (73%) had hyperlipidemia with mean cholesterol of 287 +/- 42 mg/dl. Twenty-eight patients (93%) were successfully treated with AoI. The ankle/brachial indices improved from pre-AoI ABI of 0.55 +/- 0.1 to post-AoI ABI of 0.99 +/- 0.1. Complications included one groin hematoma and one case of thrombosis. Follow-up averaged 31 months (range, 3-91 months) with an early (less than 12 months) restenosis rate of 7% and late (greater than 12 months) restenosis of 21%. One patient (3%) required surgical revascularization for persistent symptoms. Percutaneous treatment of HAIS is an alternative to surgical revascularization with satisfactory long-term results.

We have demonstrated the feasibility of accurate simultaneous OCT/FLIM morphological and biochemical characterization of coronary plaques at spatial resolutions and acquisition speeds compatible with catheter-based intravascular imaging. The success of this pilot study sets up future development of a multimodal intravascular imaging system that will enable studies that could help improve our understanding of plaque pathogenesis.