Experience of temporary inferior vena cava filters inserted in the perinatal period to prevent pulmonary embolism in pregnant women with deep vein thrombosis

ObjectiveWe placed temporary inferior vena cava filters to prevent pulmonary thromboembolism in patients with deep vein thrombosis (DVT) who were presumed to have an increased risk of pulmonary embolism in the perinatal period. These experiences of using temporary inferior vena cava filters in pregnant women are reported.MethodsWe reviewed 11 patients with DVT who underwent placement of a temporary inferior vena cava filter and delivered in our hospital between 1998 and 2004. All of the filters were placed at the suprarenal inferior vena cava before delivery. During filter placement, anticoagulant therapy was routinely performed, and we stopped the administration of anticoagulant agents intrapartum.ResultsNo complications occurred at filter insertion or during placement. No symptomatic pulmonary thromboembolism occurred during or after delivery. All of the filters were successfully removed, one of which was exchanged for a permanent filter because the temporary filter captured a large thrombus.ConclusionIntrapartum temporary inferior vena cava filters may reduce the incidence of pulmonary thromboembolism in pregnancy with DVT. Temporary inferior vena cava filters appear to be safe for pregnant women

Dynamic control of microbial movement by photoswitchable ATP antagonists

Adenosine triphosphate (ATP) is the energy source for various biochemical processes and biomolecular motors in living things. Development of ATP antagonists and their stimuli-controlled actions offer a novel approach to regulate biological processes. Herein, we developed azobenzene-based photoswitchable ATP antagonists for controlling the activity of motor proteins; cytoplasmic and axonemal dyneins. The new ATP antagonists showed reversible photoswitching of cytoplasmic dynein activity in an in vitro dynein-microtubule system due to the trans and cis photoisomerization of their azobenzene segment. Importantly, our ATP antagonists reversibly regulated the axonemal dynein motor activity for the force generation in a demembranated model of Chlamydomonas reinhardtii. We found that the trans and cis isomers of ATP antagonists significantly differ in their affinity to the ATP binding site