Role of the Toll-like receptor pathway in the recognition of orthopedic implant wear-debris particles.

The inflammatory response to prosthetic implant-derived wear particles is the primary cause of bone loss and aseptic loosening of implants, but the mechanisms by which macrophages recognize and respond to particles remain unknown. Studies of innate immunity demonstrate that Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPS). All TLRs signal through myeloid differentiation factor 88 (MyD88), except TLR3 which signals through TIR domain containing adapter inducing interferon-beta (TRIF), and TLR4 which signals through both MyD88 and TRIF.

Direct visualization of cardiac radiofrequency ablation lesions.

Effective ablation of atrial fibrillation and other cardiac arrhythmias requires precise catheter navigation and controlled delivery of energy to cardiac tissue. In this study, we summarize our initial experience using a fiber optic direct visualization catheter to evaluate and guide placement of endocardial radiofrequency (RF) ablation lesions. RF lesions were created in cadaveric porcine hearts and examined in a blood-filled field using a direct visualization catheter.

Bilateral knee arthrodesis in a patient with common variable immunodeficiency.

Patients with common variable immunodeficiency can present with debilitating arthritis. We present the case of a 42-year-old man with bilateral knee arthritis who underwent a right total knee arthroplasty that subsequently became infected. Five months after resection arthroplasty, his right leg spontaneously fused in extension, but his left knee was limited to an arc of motion between 90° and 110°.

Visualizing ablation gaps in vitro using a deflectable fiber optic endocardial visualization catheter.

Background: The efficacy of pulmonary vein isolation for the treatment of atrial fibrillation may be limited by the ability to make continuous and transmural lesions utilizing an ablation catheter. Gaps often persist between ablation lesions leading to failed electrical isolation and thus failed ablation. Recently, a deflectable fiberoptic endocardial visualization catheter has been introduced for use in imaging the coronary sinus using light in the visible spectrum.