Fully Automatic and Real-Time Catheter Segmentation in X-Ray Fluoroscopy

Augmenting X-ray imaging with 3D roadmap to improve guidance is a common strategy. Such approaches benefit from automated analysis of the X-ray images, such as the automatic detection and tracking of instruments. In this paper, we propose a real-time method to segment the catheter and guidewire in 2D X-ray fluoroscopic sequences. The method is based on deep convolutional neural networks. The network takes as input the current image and the three previous ones, and segments the catheter and guidewire in the current image. Subsequently, a centerline model of the catheter is constructed from the segmented image. A small set of annotated data combined with data augmentation is used to train the network. We trained the method on images from 182 X-ray sequences from 23 different interventions. On a testing set with images of 55 X-ray sequences from 5 other interventions, a median centerline distance error of 0.2 mm and a median tip distance error of 0.9 mm was obtained. The segmentation of the instruments in 2D X-ray sequences is performed in a real-time fully-automatic manner.Comment: Accepted to MICCAI 201

The Lantern Vol. 8, No. 1, December 1939

• Christmas Resurrection • Autumn\u27s Song • Henry Cavendish • The Mystery of Loon Cove • All Hail, Fair Modesty • Mischall • Gift of the Magi • Camera-Phobia • One Envying a Poet • Sonnetshttps://digitalcommons.ursinus.edu/lantern/1019/thumbnail.jp

The Lantern Vol. 7, No. 3, June 1939

• Commencement Sonnet • Largo Appassionato • More Sonnets to Earth • Vladimir • Abe Lincoln in Illinois • Dark Lives • Enter Mr. Smithingham II • A Character is Sketched • Sonnet • Out of the Dawn • Wistaria • Poem Without a Name • You Have Loved the Nighthttps://digitalcommons.ursinus.edu/lantern/1018/thumbnail.jp

The Lantern Vol. 8, No. 3, May 1940

• Sonnet for These Days • Peace Be With You • Creative Citizenship • Tony Solves an Ichthyological Problem • Tippy Tin • A Surgeon Paints • Thoughts • Standing at Ease • Nature\u27s Mistake • Tomorrow • This is Enough • I Built a Shrine to Love • Integer • I Look for Herhttps://digitalcommons.ursinus.edu/lantern/1021/thumbnail.jp

The Lantern Vol. 7, No. 2, March 1939

• Editorial • Easter Eggs • Fever • Sonnets to the Planet We Call Earth • Asking Her Father • New Hampshire Ghost Story • Mary • On Approaching Death • On Turning Over a New Leaf • In Defense of Americanism • What is this Love? • Martyrs of Progress • Recurring • Splintershttps://digitalcommons.ursinus.edu/lantern/1013/thumbnail.jp

The Lantern Vol. 8, No. 2, March 1940

• The Music of Life • The Dice Were Loaded • Collecting People • Chemistry and Disease • Quest • Comrade • Entity • We Cannot Go On Forever • The Problem • Beside a Campfire • Smoke • Sunset on Winnipesaukee and Varied Reflections • All\u27s Quiet in the Early Morn • Torture • After the Concert • Nostalgiahttps://digitalcommons.ursinus.edu/lantern/1020/thumbnail.jp

The Lantern Vol. 7, No. 2, March 1939

• Editorial • Easter Eggs • Fever • Sonnets to the Planet We Call Earth • Asking Her Father • New Hampshire Ghost Story • Mary • On Approaching Death • On Turning Over a New Leaf • In Defense of Americanism • What is this Love? • Martyrs of Progress • Recurring • Splintershttps://digitalcommons.ursinus.edu/lantern/1013/thumbnail.jp

Transcriptional Regulation of N-Acetylglutamate Synthase

The urea cycle converts toxic ammonia to urea within the liver of mammals. At least 6 enzymes are required for ureagenesis, which correlates with dietary protein intake. The transcription of urea cycle genes is, at least in part, regulated by glucocorticoid and glucagon hormone signaling pathways. N-acetylglutamate synthase (NAGS) produces a unique cofactor, N-acetylglutamate (NAG), that is essential for the catalytic function of the first and rate-limiting enzyme of ureagenesis, carbamyl phosphate synthetase 1 (CPS1). However, despite the important role of NAGS in ammonia removal, little is known about the mechanisms of its regulation. We identified two regions of high conservation upstream of the translation start of the NAGS gene. Reporter assays confirmed that these regions represent promoter and enhancer and that the enhancer is tissue specific. Within the promoter, we identified multiple transcription start sites that differed between liver and small intestine. Several transcription factor binding motifs were conserved within the promoter and enhancer regions while a TATA-box motif was absent. DNA-protein pull-down assays and chromatin immunoprecipitation confirmed binding of Sp1 and CREB, but not C/EBP in the promoter and HNF-1 and NF-Y, but not SMAD3 or AP-2 in the enhancer. The functional importance of these motifs was demonstrated by decreased transcription of reporter constructs following mutagenesis of each motif. The presented data strongly suggest that Sp1, CREB, HNF-1, and NF-Y, that are known to be responsive to hormones and diet, regulate NAGS transcription. This provides molecular mechanism of regulation of ureagenesis in response to hormonal and dietary changes