title: Multiple microscopy modalities applied to a sea urchin tooth fragment.
abstract: Two synchrotron X-ray microscopy methods, phase-contrast microradiography (the propagation method) and absorption microCT (high-resolution computed tomography or microtomography), and laser-scanning confocal microscopy (visible wavelength) were used to study a fragment of the keel of a tooth of the sea urchin Lytechinus variegatus. Stripes observed in the phase-contrast images of the fragment were also seen in confocal micrographs. MicroCT showed that the stripes were due to two parallel planar arrays of low-absorption channels within the bulk of the keel. In the phase microradiographs, maximum contrast stripes appear when a channel image from one row coincides with a channel image from the second row; otherwise, contrast is minimal. Long channels do not appear to have been observed previously in keels of sea urchin teeth.
authors.affiliation: Institute for Bioengineering and Nanoscience in Advanced Medicine, Ward 13-130, Northwestern University, 303 East Chicago Avenue, Chicago, IL 60611-3008, USA. s-stock@northwestern.edu
authors.forename: S R
authors.initials: SR
authors.lastname: Stock
authors.forename: K
authors.initials: K
authors.lastname: Ignatiev
authors.forename: T
authors.initials: T
authors.lastname: Dahl
authors.forename: J
authors.initials: J
authors.lastname: Barss
authors.forename: K
authors.initials: K
authors.lastname: Fezzaa
authors.forename: A
authors.initials: A
authors.lastname: Veis
authors.forename: W K
authors.initials: WK
authors.lastname: Lee
authors.forename: F
authors.initials: F
authors.lastname: De Carlo
mesh_terms: D000818:Animals; D008852:Microradiography / Q000379:methods*; D018613:Microscopy, Confocal / Q000379:methods*; D008858:Microscopy, Phase-Contrast / Q000379:methods*; D012617:Sea Urchins; D017356:Synchrotrons; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014070:Tooth / Q000000981:diagnostic imaging* / Q000648:ultrastructure