Inserm, Universite Paris Descartes 2 articles published in JoVE Biology Phage-mediated Delivery of Targeted sRNA Constructs to Knock Down Gene Expression in E. coli Aude G. Bernheim*1, Vincent K. Libis*1, Ariel B. Lindner1, Edwin H. Wintermute1 1U1001, Institut National de la Santé et de la Recherche Médicale (INSERM), Université Paris Descartes We describe a method to knock down gene expression in a growing population of E. coli cells using sequence-targeted sRNA expression cassettes delivered by an M13 phagemid vector. Medicine In vivo Imaging of Tumor Angiogenesis using Fluorescence Confocal Videomicroscopy Victor Fitoussi1, Nathalie Faye1, Foucauld Chamming's1,2, Olivier Clement1,2, Charles-Andre Cuenod1,2, Laure S. Fournier1,2 1Université Paris Descartes Sorbonne Paris Cité, INSERM UMR-S970, 2Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Radiologie In this paper, we present a method to analyze tumor microvessels in vivo using dynamic contrast-enhanced fluorescence videomicroscopy. Two quantitative parameters were acquired: functional capillary density reflecting the vascularity of the tumor, and index leakage reflecting the leakiness of the endothelial wall.