Perioperative Management of Hepatitis C in Patients Undergoing Total Joint Arthroplasty.

»: A small yet growing subset of total joint arthroplasty (TJA) candidates are diagnosed with the hepatitis C virus (HCV), which is a known risk factor for periprosthetic joint infections. Given the poor outcomes associated with TJA infection, we recommend that candidates with HCV receive treatment prior to elective TJA.

»: Interferon and ribavirin have historically been the standard treatment regimen for the management of HCV; however, adverse events and an inconsistent viral response have limited the efficacy of these therapies.

Head Loss As an Explanation of the Steal Phenomenon in Microvascular Surgery.

Vascular steal has been cited to help explain end-organ ischemia after microvascular reconstruction. Attempts to clarify a mechanism of vascular steal have been made by modeling blood circulation after a simple electrical circuit, suggesting that the free flap provides a path of least resistance for blood flow and thereby compromises end-organ perfusion. We present a case of a posterior medial thigh perforator flap for the reconstruction of a diabetic foot ulcer in a patient with a single vessel providing inflow to the foot.

Structural basis for diversity in the SAM clan of riboswitches.

In bacteria, sulfur metabolism is regulated in part by seven known families of riboswitches that bind S-adenosyl-l-methionine (SAM). Direct binding of SAM to these mRNA regulatory elements governs a downstream secondary structural switch that communicates with the transcriptional and/or translational expression machinery. The most widely distributed SAM-binding riboswitches belong to the SAM clan, comprising three families that share a common SAM-binding core but differ radically in their peripheral architecture.