Low-flow intussusception and metastable VEGFR2 signaling launch angiogenesis in ischemic muscle.

Efforts to promote sprouting angiogenesis in skeletal muscles of individuals with peripheral artery disease have not been clinically successful. We discovered that, contrary to the prevailing view, angiogenesis following ischemic muscle injury in mice was not driven by endothelial sprouting. Instead, real-time imaging revealed the emergence of wide-caliber, primordial conduits with ultralow flow that rapidly transformed into a hierarchical neocirculation by transluminal bridging and intussusception.

Vibration of osteoblastic cells using a novel motion-control platform does not acutely alter cytosolic calcium, but desensitizes subsequent responses to extracellular ATP.

Low-magnitude high-frequency mechanical vibration induces biological responses in many tissues. Like many cell types, osteoblasts respond rapidly to certain forms of mechanostimulation, such as fluid shear, with transient elevation in the concentration of cytosolic free calcium ([Ca ] ). However, it is not known whether vibration of osteoblastic cells also induces acute elevation in [Ca ] .

Practical fabrication of microfluidic platforms for live-cell microscopy.

We describe a simple fabrication technique - targeted towards non-specialists - that allows for the production of leak-proof polydimethylsiloxane (PDMS) microfluidic devices that are compatible with live-cell microscopy. Thin PDMS base membranes were spin-coated onto a glass-bottom cell culture dish and then partially cured via microwave irradiation. PDMS chips were generated using a replica molding technique, and then sealed to the PDMS base membrane by microwave irradiation.

Examining Practitioners' Assessments of Perceived Aesthetic and Diagnostic Quality of High kVp-Low mAs Pelvis, Chest, Skull, and Hand Phantom Radiographs.

This study investigated the usefulness of the dose optimization strategy of increased tube voltage (kVp) and decreased tube current-exposure time product (mAs) (or high kVp-low mAs) by examining practitioners' assessments of perceived aesthetic and diagnostic quality of direct digital radiographs acquired using this strategy. Ninety-one practitioners (radiologists, radiology residents, radiographers, and radiography students) from eight clinical sites in Ontario examined three types of radiographs ("standard" image, +20 kVp image, and +30 kVp image) for anthropomorphic pelvis, chest, skull, and hand phantoms and rated (on a five-point scale) each image in regard to its perceived aesthetic quality, perceived diagnostic quality, and visualization of anatomic structures. Our primary findings are that for the pelvis, skull, and hand-although not the chest-images acquired using standard technical factors were rated significantly higher in diagnostic and aesthetic quality than those acquired using the high kVp-low mAs strategy.

Regional measurements of surface deviation volume in worn polyethylene joint replacement components.

Total joint replacements can be subject to the loss of polyethylene material due to wear, leading to osteolysis and decreased implant longevity. Micro-computed tomography (micro-CT) techniques have recently been developed to calculate 3D surface deviations in worn implant components. We describe a micro-CT technique to measure the volume of the surface deviations (volume of wear plus creep) within a specific region or compartment, and report its repeatability and reproducibility.