Scaffolds play a key role in the process of regeneration and morphogenesis of tissue or organ. We have developed a novel sonication decellularization system to prepare decellularized bio-scaffolds in a short treatment time. The aim of the study is to investigate sonication decellularization condition that completely decellularize meniscus can be changed as well as to maintain the biomechanical parameters of scaffolds. The meniscus samples were decellularized using sonication treatment. The treated samples were evaluated histologically by EVG for cell removal, picrosirius red for content of collagen type I and III, and safranin-O/fast green staining for content of glycosaminoglycan, and SEM for observation of scaffold surface. Indentation apparatus was used to analyze the unconfined deformation under load of native and decellularized menisci. The load parameters which are stiffness, compression and residual force were not significantly different compare with native and sonicated scaffolds. However, the content of extracellular matrix and its fiber alignment changed significantly due to sonication treatment as observed by SEM and safranin-O/fast green staining, respectively. The removal of immunogenic cell components by sonication decellularization as well as maintain its biomechanical strength of decellularized scaffolds, so that it has potential to use as an implant material for tissue engineering of menisci.

No abstract

This study prospectively investigated 3,118 standard 12-lead ECGs recorded in 1,804 patients, who participated in the Losartan Heart Failure Survival Study--ELITE II clinical trial. After exclusion of patients with rhythms other than sinus, or atrioventricular block, or poor quality ECGs, 986 (703 men, mean age 71 +/- 7 years) with baseline ECGs were retained, of whom 615 patients had follow-up ECGs 4 months after randomization. QT intervals were manually measured with a digitizing board. Heart rate, QRS duration, maximum QT and JT intervals, QT and JT dispersion (the interval ranges across all measurable ECG leads) were analyzed. In the overall population, there were 140 (14%) deaths from all causes, including 119 (12%) cardiac and 59 (6%) sudden deaths during a follow-up of 540 +/- 153 days. The mean heart rate was significantly faster in nonsurvivors than in survivors (77 +/- 16 vs 74 +/- 14 beats/min, P = 0.006), and in patients who died of cardiac death (76 +/- 16 beats/min, P = 0.04 vs survivors). Mean QRS duration was significantly longer in nonsurvivors (107 +/- 25 ms), and in the subgroups who died of cardiac (107 +/- 24 ms) or sudden death (112 +/- 23 ms) than in survivors (99 +/- 24 ms, P < 0.01 for all). The maximum and corrected (QTc) QT intervals were similar for nonsurvivors, regardless of cause of death, and in survivors (P = NS for all comparisons). Significantly shorter maximum and corrected (JTc) JT intervals were observed in victims of any mode of death compared to survivors (P < 0.05 for all). There was no significant difference in QT or JT dispersion between patients with any mode of death and survivors (P > 0.1 for all). Neither losartan nor captopril significantly modified QT or JT dispersion. In conclusion, increased QT dispersion is not associated with increased mortality in patients with heart failure, and is not suitable to examine drug efficacy in these patients.

The budding yeast, Saccharomyces cerevisiae, is an attractive host for studying G protein-coupled receptors (GPCRs). We developed a system in which a peptide ligand specific for GPCR is displayed on yeast plasma membrane. The model system described here is based on yeast plasma membrane display of an analogue of α-factor, which is a peptide ligand for Ste2p, the GPCR that activates the yeast pheromone response pathway. α-Factor analogues, containing linkers of varying lengths and produced in yeast cells, became attached to the cell plasma membrane by linking to the glycosylphosphatidylinositol (GPI)-anchored plasma membrane protein Yps1p. We were able to demonstrate that an optimized α-factor analogue activated the pheromone response pathway in S. cerevisiae, as assessed by a fluorescent reporter assay. Furthermore, it was shown that linker length strongly influenced signalling pathway activation. To our knowledge, this is the first report documenting functional signalling by a plasma membrane-displayed ligand in S. cerevisiae.