Citations

Background and Purpose— We sought to determine the vascular risk factors and demographic features associated with the severity and location of intracranial stenosis. Methods— Data on patients enrolled in the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial were used for the analyses. Demographic features and vascular risk factors were compared in patients with moderate stenosis (n=336) versus severe stenosis (n=225) and according to the location of intracranial stenosis (middle cerebral, internal carotid, basilar, or vertebral artery). Results— History of a lipid disorder (77% in severe vs 67% in moderate, P =0.01), metabolic syndrome (63% in severe vs 53% in moderate, P =0.05), and diabetes (43% in severe vs 35% in moderate, P =0.04) were more common in patients with severe intracranial stenosis by univariate analyses. A history of a lipid disorder was independently associated with severe stenosis (odds ratio=1.62; 95% CI, 1.09 to 2.42; P =0.02). The distribution of stenosis location differed among age groups ( P =0.0015), sexes ( P =0.0001), races ( P =0.0243), qualifying events ( P =0.0156), diabetes ( P =0.0030), coronary artery disease ( P =0.0030), and hyperlipidemia ( P =0.054). Patients with basilar artery stenoses were older and more likely to have hyperlipidemia. Patients with middle cerebral artery stenoses were more likely to be women and black. Patients with internal carotid artery stenoses were more likely to have diabetes. Patients with vertebral artery stenoses were more likely to have coronary artery disease. Conclusions— History of a lipid disorder had the strongest association with severity of intracranial stenosis and should be the target of prevention therapies. Different locations of intracranial stenoses are associated with different vascular risk factors and demographic features, suggesting that there may be a difference in the underlying pathophysiology of stenoses among the intracranial arteries.

Abstract Type I alveolar epithelial cells (ATIs) are very large, thin cells, which extend across several air sacs and cover more than 95% of the alveolar surface area. ATIs are the target of many insults, including ventilator-induced lung injury, and are generally considered terminally differentiated cells arising from type II cell (ATII) lineage. ATIs have proven difficult to harvest and maintain in primary culture, which is why much of ATI biology has been inferred from studies on ex vivo, ATII-derived, so-called ATI-like cells. We report on a modified approach to rat ATI harvest and primary culture, which yielded the following observations: (1) rat ATI can be harvested and maintained with a high degree of purity in primary culture; (2) in vitro growth characteristics of primary ATIs differ from those of ATII-derived ATI-like cells; ATIs, but not ex vivo, ATII-derived ATI-like cells, are capable of cell division; (3) ATIs readily repair plasma membrane wounds without the subsequent loss of their ability to divide; (4) ATI monolayers heal scratch wounds primarily by cell spreading and migration. Although the ability of ATIs to divide may be limited to the in vitro environment, we do believe that their role in alveolar wound repair deserves to be revisited, and the molecular control of ATI–ATII plasticity further explored.