Potential air contamination during CO2 angiography using a hand-held syringe: theoretical considerations and gas chromatography.

Purpose: To assess air contamination in the hand-held syringes currently used for CO2 delivery and to determine whether there is an association between their position and the rate of air contamination.

Methods: Assessment of air contamination in the syringe (20 ml) included theoretical modeling, mathematical calculation, and gas chromatography (GC). The model was used with Fick's first law to calculate the diffusion of CO2 and the amount of air contamination.

A simple DSA method to detect air contamination during CO2 venous studies.

The use of CO2 as a contrast agent has increased significantly for visualization of the central veins, inferior vena cava, and portal vein. The most serious complication associated with CO2 studies is air contamination. We evaluated a simple digital subtraction angiogram (DSA) method to detect air contamination during CO2 venous studies.

Gene expression clustering using self-organizing maps: analysis of the macrophage response to particulate biomaterials.

The most common cause of total joint replacement failure is peri-implant bone loss causing pain and prosthesis loosening. This process, known as osteolysis or aseptic loosening, is characterized by macrophage phagocytosis of particulate implant wear debris. In an incompletely defined step, particulate biomaterial debris induces macrophages to release a variety of inflammatory mediators and signaling proteins that lead to bone loss.

CO2 digital subtraction splenoportography with the "skinny" needle: experimental study in a swine model.

Purpose: To evaluate the safety and the effectiveness of CO2 splenoportography with the "skinny" needle.

Methods: A flexible, 22 gauge needle ("skinny" needle) was introduced into the exteriorized spleens of five pigs. After checking the intrasplenic positioning with CO2 injection, increasing doses of CO2 (10-60 cm3) were injected using a dedicated CO2 injector with digital imaging.

The role of adsorbed endotoxin in particle-induced stimulation of cytokine release.

Numerous in vitro models have demonstrated the capacity of wear particles to stimulate the release of soluble pro-inflammatory products with the ability to induce local bone resorption. Recent observations have demonstrated that binding of lipopolysaccharide (LPS) to particulate wear debris can significantly modulate the pattern of cell response in the in vitro models. These findings raise concerns over the possible role of LPS in the pathogenesis of aseptic loosening after total joint replacements, and also indicates the importance of controlling for possible confounding effects of LPS contamination in the in vitro models used to study the reactive nature of wear debris.

Microscopic metallic wear and tissue response in failed titanium hallux metatarsophalangeal implants: two cases.

The membranes present at the implant-bone interface were retrieved from two patients with titanium single stem hallux implants that had failed. Both patients had pain and valgus deformity of the hallux, and radiographs showed a radiolucent shadow around the implant stem, with thinning of the dorsal cortex of the proximal phalanx in one patient. After removal of the implants, arthrodesis of the first metatarsophalangeal (MP) joint was performed.