Cerebral MRI scanning frequently shows white matter lesions in elderly people. They are related to cognitive impairment and may result in dementia. Although vascular risk factors are associated with the presence of white matter lesions, the exact pathogenesis remains unclear. Animal studies have indicated involvement of endothelial cells in the pathogenesis of white matter lesions and possibly dementia. We investigated the relation between endothelial cell activation and white matter lesions in individuals with cerebrovascular disease. In 29 patients with an acute stroke (n = 11) or TIAs associated with a symptomatic internal carotid artery stenosis (n = 18), markers of endothelial cell activation such as intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1), sE-selectin, and sP-selectin were measured by means of ELISA. All individuals underwent 1.5-T MRI scanning. White matter lesions were rated for the periventricular and the subcortical region separately. Individuals with severe periventricular white matter lesions had higher levels of sP-selectin (245.5 ng/mL vs. 172.7 ng/mL, p = 0.01) and sVCAM-1 (547.8 ng/mL vs. 454.0 ng/mL, p = 0.04) than those without. This association was only found in individuals with a symptomatic carotid artery stenosis. No such association was found for subcortical white matter lesions. We did not detect any relation between sICAM-1 and sE-selectin and white matter lesions. Endothelial cell activation may play a role in the pathogenesis of white matter lesions, especially in periventricular white matter. Possibly, this activation represents the influence of vascular factors on the cerebral endothelium as a prelude to increasingly severe small vessel disease.

Objectives The lecithin/sphingomyelin (L/S) ratio and the lamellar body count (LBC) can be used to predict respiratory distress syndrome (RDS). Design We performed a retrospective cohort study among consecutive women who underwent amniotic Xuid sampling for the assessment of fetal lung maturity. Logistic regression was used to construct models for the prediction of RDS in three gestational age categories, with models based on clinical characteristics only, clinical characteristics and the LBC, and on clinical characteristics and L/S ratio. Results When amniotic Xuid was collected <30 weeks, the speciWcity of the LBC was 30% and the sensitivity 100%. Addition of the L/S ratio increased the speciWty to 60%, for a sensitivity of 100%. When amniocentesis was performed between 30 and 33 weeks, addition of the L/S ratio only marginally improved the performance of the LBC. Conclusions At a gestational age <30 weeks, the L/S ratio has additional value over the LBC. Above 30 weeks of gestation, single use of the LBC seems suYcient.

Fetal lung maturity tests that are performed in vaginally obtained specimens in patients with ruptured membranes are of no use in the prediction of RDS.