ABSTRACT
Aneurysms need accurate millimeters (mm). Direct millimeters were lost with digital subtraction angiography (DSA) years ago, with measurements in pixels. Advances in DSA can now give inherent millimeters. The Cerecyte aneurysm coiling trial's angiographic core lab assesses images from compact disc (CD). External fiducials for millimeter calibration are required. Of 25 cases with two 10 mm fiducials, near and far from the intensifier, the midline mean is between 9 "mm" to 15 "mm". Yet 10 mm must be 10 mm. This variance is potentially dangerous. Proprietary software seems to prohibit calibration transfer via CD to another vendor's system.
Subject(s)
Angiography, Digital Subtraction/standards , Cerebral Angiography/standards , Image Processing, Computer-Assisted/standards , Intracranial Aneurysm/diagnostic imaging , Angiography, Digital Subtraction/methods , Calibration , Cerebral Angiography/methods , Humans , Image Processing, Computer-Assisted/methods , SoftwareABSTRACT
The Wnt signalling cascade is essential for the development of both invertebrates and vertebrates, and is altered during tumorigenesis. Although a general framework for Wnt signalling has been elucidated, not all of the components have been identified. Here we describe a serine kinase, casein kinase I (CKI), which was isolated by expression cloning in Xenopus embryos. CKI reproduces several properties of Wnt signals, including generation of complete dorsal axes, stabilization of beta-catenin and induction of genes that are direct targets of Wnt signals. Dominant-negative forms of CKI and a pharmacological blocker of CKI inhibited Wnt signals in Xenopus. Inhibiting CKI in Caenorhabditis elegans generated worms with a mom phenotype, indicative of a loss of Wnt signals. In addition, CKI bound to and increased the phosphorylation of dishevelled, a known component of the Wnt pathway. These data indicate that CKI may be a conserved component of the Wnt pathway.
