Lipid compositional asymmetry across the leaflets of the plasma membrane is an ubiquitous feature in eukaryotic cells. How this asymmetry is maintained is thought to be primarily controlled by active transport of lipids between leaflets. This strategy is facilitated by the fact that long-tail phospholipids and sphingolipids diffuse through the lipid bilayer slowly-taking many hours or days.
View Article and Find Full Text PDFAm J Respir Cell Mol Biol
May 2014
An emerging tool in airway biology is the precision-cut lung slice (PCLS). Adoption of the PCLS as a model for assessing airway reactivity has been hampered by the limited time window within which tissues remain viable. Here we demonstrate that the PCLS can be frozen, stored long-term, and then thawed for later experimental use.
View Article and Find Full Text PDFPurpose Of Review: Asthma is a major public health problem that afflicts nearly one in 20 people worldwide. Despite available treatments, asthma symptoms remain poorly controlled in a significant minority of asthma patients, especially those with severe disease. Accordingly, much ongoing effort has been directed at developing new therapeutic strategies; these efforts are described in detail below.
View Article and Find Full Text PDFAm J Respir Crit Care Med
August 2012
Rationale: In the normal lung, breathing and deep inspirations potently antagonize bronchoconstriction, but in the asthmatic lung this salutary effect is substantially attenuated or even reversed. To explain these findings, the prevailing hypothesis focuses on contracting airway smooth muscle and posits a nonlinear dynamic interaction between actomyosin binding and the tethering forces imposed by tidally expanding lung parenchyma.
Objective: This hypothesis has never been tested directly in bronchial smooth muscle embedded within intraparenchymal airways.
Breathing is known to functionally antagonize bronchoconstriction caused by airway muscle contraction. During breathing, tidal lung inflation generates force fluctuations that are transmitted to the contracted airway muscle. In vitro, experimental application of force fluctuations to contracted airway smooth muscle strips causes them to relengthen.
View Article and Find Full Text PDFIncreasing evidence indicates that the beneficial "pleiotropic" effects of statins on clinical events involve nonlipid mechanisms including the modification of blood vessel endothelial cell function. However, the involved molecular events and pathways are not completely understood. In the present study, Affymetrix microarrays were used to monitor the temporal gene expression of human coronary artery endothelial cells (HCAEC) treated with simvastatin (Sim) to gain insight into statins' direct effects on the endothelial function.
View Article and Find Full Text PDFAm J Respir Cell Mol Biol
January 2006
Long-term success in lung transplantation is limited by obliterative bronchiolitis, whereas T cell effector mechanisms in this process remain incompletely understood. Using the mouse heterotopic allogeneic airway transplant model, we studied T cell effector responses during obliterative airways disease (OAD). Allospecific CD8+ IFN-gamma+ T cells were detected in airway allografts, with significant coexpression of TNF-alpha and granzyme B.
View Article and Find Full Text PDFPrior genomic and genetic studies identified pre-B-cell colony-enhancing factor (PBEF) as a novel candidate gene and biomarker in acute lung injury (ALI). As increased vascular permeability is a cardinal feature of ALI, we assessed the role of PBEF in in vitro vascular barrier regulation using confluent human pulmonary artery endothelial cell (HPAEC) monolayers. Reductions in PBEF protein expression (>70%) by siRNA significantly attenuated EC barrier dysfunction induced by the potent edemagenic agent, thrombin, reflected by reductions in transendothelial electric resistance (TER, approximately 60% reduction).
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