Plasma lipoprotein levels are predictors of risk for coronary artery disease. Lipoprotein structure-function relationships provide important clues that help identify the role of lipoproteins in cardiovascular disease. The compositional and conformational heterogeneity of lipoproteins are major barriers to the identification of their structures, as discovered using traditional approaches. Although electron microscopy (EM) is an alternative approach, conventional negative staining (NS) produces rouleau artifacts. In a previous study of apolipoprotein (apo)E4-containing reconstituted HDL (rHDL) particles, we optimized the NS method in a way that eliminated rouleaux. Here we report that phosphotungstic acid at high buffer salt concentrations plays a key role in rouleau formation. We also validate our protocol for analyzing the major plasma lipoprotein classes HDL, LDL, IDL, and VLDL, as well as homogeneously prepared apoA-I-containing rHDL. High-contrast EM images revealed morphology and detailed structures of lipoproteins, especially apoA-I-containing rHDL, that are amenable to three-dimensional reconstruction by single-particle analysis and electron tomography.

Apolipoprotein E (apoE), one of the major protein components of lipoproteins in the peripheral and central nervous systems, regulates cholesterol metabolism through its interaction with members of the low density lipoprotein receptor family. One key to understanding apoE function is determining the structure of lipid-bound forms of apoE. Negative-staining (NS) electron microscopy (EM) is an easy and rapid approach for studying the structure and morphology of lipid-bound forms of apoE. However, an artifact of using the conventional NS protocol is that the apoE•phospholipid particles form rouleaux. In this study, we used cryo-electron microscopy (cryo-EM) to examine apoE4•palmitoyl-oleoylphosphatidylcholine (POPC) particles in a frozen-hydrated native state. By comparing the particle sizes and shapes produced by different NS protocols to those produced by cryo-EM, we propose an optimized protocol to examine apoE4•POPC particles. Statistical analysis demonstrated that the particle sizes differ by less than 5% between the optimized protocol and the cryo-EM method, with similar shapes. The high contrast and fine detail of particle images produced using this optimized protocol lend themselves to the structural study of lipid-bound forms of apoE.

Postoperative medical complications in these elderly, debilitated patients related to pulmonary problems and alcohol withdrawal were statistically far more important in negatively affecting the outcomes and true costs of microsurgical reconstruction.

Once daily IV/PO moxifloxacin monotherapy was as least as effective as standard IV piperacillin-tazobactam/PO amoxicillin-clavulanate dosed multiple times daily for the treatment of cIAIs.

Intravenous+/-oral moxifloxacin was as effective as iv piperacillin-tazobactam+/-amoxicillin-clavulanate in treating moderate-to-severe DFIs. Moxifloxacin may have potential as a monotherapy regimen for DFIs.

No abstract

As defined by bacteriological success in the population assessed for microbiological efficacy, prophylaxis with one dose of ciprofloxacin XR was statistically no worse than a 3-day regimen. However, in all efficacy analyses, bacteriological and clinical success rates were consistently lower for the 1-day than for the 3-day treatment. Thus, for selected patients undergoing TRNBP, there might be a role for 3-day preventive therapy with ciprofloxacin XR.

Extended release ciprofloxacin at a dose of 1,000 mg once daily was as safe and effective as conventional treatment with 500 mg ciprofloxacin twice daily, each given orally for 7 to 14 days in adults with cUTI or AUP. It provides a convenient, once daily, empirical treatment option.