To identify potential regulators of smooth muscle cell (SMC) differentiation, we studied the molecular mechanisms that control the tissue-specific transcriptional expression of SM alpha-actin, the most abundant protein in fully differentiated SMCs. A construct containing the region from -1 to -125 of the promoter (p125CAT) had high transcriptional activity in SMCs (57-fold > promoterless) and endothelial cells (ECs) (18-fold) but not in skeletal myoblasts or myotubes. Mutation of either of two highly conserved CC(AT-rich)6GG (CArG) motifs at -62 and -112 abolished the activity of p125CAT in SMCs but had no effect in ECs. In contrast, high transcriptional activity in skeletal myotubes, which also express SM alpha-actin, required at least 271 base pairs of the promoter (-1 to > or = -271). Constructs containing 547 base pairs or more of the promoter were transcriptionally active in SMCs and skeletal myotubes but had no activity in skeletal myoblasts or ECs, cell types that do not express SM alpha-actin. Electrophoretic mobility shift assays provided evidence for binding of a unique serum response factor-containing complex of factors to the CArG box elements in SMCs. Results indicate that: 1) transcriptional expression of SM alpha-actin in SMCs requires the interaction of the CArG boxes with SMC nucleoprotein(s); 2) expression of SM alpha-actin in skeletal myotubes requires different cis-elements and trans-factors than in SMCs; and 3) negative-acting cis-elements are important in restricting transcription in cells that do not express SM alpha-actin.

Implementation of thoracic ERAS is a dynamic process with potential to improve outcomes in thoracic surgical procedures. In the first year we shortened length of stay, decreased opioid usage, minimized fluid overload, and decreased hospital costs.

Previously, we demonstrated that treatment of postconfluent quiescent rat aortic smooth muscle cells (SMCs) with platelet-derived growth factor (PDGF)-BB dramatically reduced smooth muscle (SM) a-actin synthesis. In the present studies, we focused on the expression of two other SM-specific proteins, SM myosin heavy chain (SM-MHC) and SM a-tropomyosin (SM-aTM), to determine whether the actions of PDGF-BB were specific to SM a-actin or represented a global ability of PDGF-BB to inhibit expression of cell-specific proteins characteristic of differentiated SMCs. SM-MHC and SM-aTM expression were assessed by one-or

Purpose Many cases have been reported of hemodynamic and airway collapse induced by general anesthesia in patients with an anterior mediastinal mass. We examined the literature for predictors of perioperative risk, guidelines for preoperative investigations, and strategies for management of the patient with a mediastinal mass. Principal findings In patients with an anterior mediastinal mass, symptoms may range from none to severe and may include orthopnea, stridor, cyanosis, jugular vein distension, or superior vena cava syndrome. In limited case series, incidences of serious complications up to 20% were noted, but these are primarily pediatric studies with unclear relevance to adults. There is a paucity of evidence providing guidance on quantifying risk and planning the safe conduct of anesthesia. In the largest adult case series to date, intraoperative complications were associated only with the preoperative presence of a pericardial effusion. Postoperative complications were predicted by severe symptoms at presentation, tracheal compression of [ 50%, and a mixed obstructive-restrictive picture on pulmonary function testing. Low-risk patients tolerate conventional general anesthesia with neuromuscular blockade and positive pressure ventilation. Those at intermediate or high risk are best managed with the maintenance of spontaneous ventilation, at least initially. Cardiopulmonary bypass remains the option of last resort. Conclusions It appears prudent to avoid general anesthesia when possible for patients at the highest risk. When general anesthesia is required, a comprehensive plan must be formulated preoperatively with the surgical team. Cardiopulmonary bypass requires time for implementation, so it should be considered early and appropriate preparations should be made prior to the initiation of anesthesia.

SummaryFiberoptic intubation (FOI) is an effective technique for establishing airway access in patients with both anticipated and unanticipated difficult airways. First described in the late 1960s, this approach can facilitate airway management in a variety of clinical scenarios given proper patient preparation and technique. This paper seeks to review the pertinent technology, clinical techniques, and indications for and complications of its use. The role of FOI in airway management algorithms is discussed. Evidence is presented comparing FOI to other techniques with regard to difficult airway management. In addition, we have reviewed the literature on training processes and skill development in FOI.