A randomised controlled trial of amniotic membrane in the treatment of a standardised burn injury in the merino lamb.

Burns. 2009 May 15; Fraser JF, Cuttle L, Kempf M, Phillips GE, Hayes MT, Kimble RMBurn injury is associated with disabling scar formation which impacts on many aspects of the patient's life. Previously we have shown that the fetus heals a deep dermal burn in a scarless fashion. Amniotic membrane (AM) is the outermost fetal tisue and has beeen used as a dressing in thermal injuries, though there is little data to support this use. To assess the efficacy of AM in scar minimisation after deep dermal burn wound, we conducted a randomised controlled study in the 1-month lamb. Lambs were delivered by caesarian section and the amniotic membranes stored after which lambs were returned to their mothers post-operatively. At 1 month, a standardised deep dermal burn was created under general anaesthesia on both flanks of the lamb. One flank was covered with unmatched AM, the other with paraffin gauze. Animals were sequentially euthanased from Day 3-60 after injury and tissue analysed for histopathology and immunohistochemically for alpha-smooth muscle actin (alphaSMA) content. AM resulted in reduced scar tissue as assessed histopathologically and reduced alphaSMA content. This study provides the first laboratory evidence that AM may reduce scar formation after burn injury.

CT and MR Imaging Findings in Patients with Acquired Heart Disease at Risk for Sudden Cardiac Death.

Radiographics. 2009 May-Jun; 29(3): 805-23Sparrow PJ, Merchant N, Provost YL, Doyle DJ, Nguyen ET, Paul NSNoninvasive imaging is an important screening and diagnostic tool in conditions associated with sudden cardiac death. The most common cause of sudden cardiac death is coronary artery disease, with myocarditis, cardiac sarcoidosis, and dilated and infiltrative cardiomyopathies being less common acquired causes. Common risk factors for sudden cardiac death, regardless of the disease process, include severe ventricular dysfunction and the presence of macroscopic scar seen at delayed contrast material-enhanced imaging. Recent advances in electrocardiographically (ECG) gated cardiac magnetic resonance (MR) imaging and multidetector computed tomography (CT) have led to increased referrals for cross-sectional imaging; thus, cardiac radiologists should be familiar with the disease entities associated with sudden cardiac death. Inflammatory processes and cardiomyopathies are best depicted with cardiac MR imaging. Steady-state free precession cine sequences coupled with inversion-recovery prepared gradient-echo T1-weighted sequences performed after the intravenous administration of gadolinium-based contrast material should form the basis of cardiac MR imaging protocols for cardiomyopathy. A clinical history that is suggestive of myocardial ischemia, specific requests to exclude coronary artery disease, or contraindications for MR imaging may imply that multidetector CT would be more appropriate. Nevertheless, both cardiac MR imaging and ECG-gated multidetector CT offer robust diagnosis and risk stratification for individual disease processes associated with sudden cardiac death. (c) RSNA, 2009.

Control protocol for robust in vitro glial scar formation around microwires: essential roles of bFGF and serum in gliosis.

J Neurosci Methods. 2009 May 14; Polikov VS, Su EC, Ball MA, Hong JS, Reichert WMPreviously, we reported an in vitro cell culture model that recreates many of the hallmarks of glial scarring around electrodes used for recording in the brain; however, the model lacked the reproducibility necessary to establish a useful characterization tool. This methods paper describes a protocol, modeled on protocols typically used to culture neural stem/precursor cells, that generates a predictable positive control of an intense scarring reaction. Six independent cell culture variables (growth media, seeding density, bFGF addition day, serum concentration in treatment media, treatment day, and duration of culture) were varied systematically and the resulting scars were quantified. The following conditions were found to give the highest level of scarring: Neurobasal medium supplemented with B27, 10% fetal bovine serum at treatment, 10ng/ml b-FGF addition at seeding and at treatment, treatment at least 6 days after seeding and scar growth of at least 5 days. Seeding density did not affect scarring as long as at least 500,000 cells were seeded per well, but appropriate media, bFGF, and serum were essential for significant scar formation - insights that help validate the in vitro-based approach to understanding glial scarring. With the control protocol developed in this study producing a strong, reproducible glial scarring positive control with every dissection, this culture model is suitable for the in vitro study of the mechanisms behind glial scarring and neuroelectrode failure.

Complete removal of load is detrimental to rotator cuff healing.

J Shoulder Elbow Surg. 2009 May 6; Galatz LM, Charlton N, Das R, Mike Kim H, Havlioglu N, Thomopoulos SHYPOTHESIS: This study evaluated the effect of the mechanical environment on the healing rotator cuff by paralyzing the supraspinatus muscle in the operative shoulder of a rat model of rotator cuff injury and repair. METHODS: Unilateral shoulders of rats underwent a supraspinatus injury and repair. Botulinum toxin A was used to paralyze the muscle after repair. Postoperatively, 1 group was immobilized and 1 group was allowed free range of motion. Saline-injected, casted rats were used as the control group. Repairs were evaluated histologically, geometrically, and biomechanically. RESULTS: Specimens from the saline-injected rats had greater scar volume and cross-sectional area of the repair compared with the paralyzed groups. Structural properties were increased in the saline group compared with the paralyzed groups. Free range of motion (ie, uncasted group) resulted in modest improvements in biomechanical properties but did not obviate the effect of paralysis. CONCLUSIONS: Complete removal of load was detrimental to rotator cuff healing, especially when combined with immobilization. LEVEL OF EVIDENCE: Basic science study.