title: X-ray laser microscopy of rat sperm nuclei.
abstract: The development of high brightness and short pulse width (< 200 picoseconds) x-ray lasers now offers biologists the possibility of high-resolution imaging of specimens in an aqueous environment without the blurring effects associated with natural motions and chemical erosion. As a step toward developing the capabilities of this type of x-ray microscopy, a tantalum x-ray laser at 44.83 angstrom wavelength was used together with an x-ray zone plate lens to image both unlabeled and selectively gold-labeled dried rat sperm nuclei. The observed images show approximately 500 angstrom features, illustrate the importance of x-ray microscopy in determining chemical composition, and provide information about the uniformity of sperm chromatin organization and the extent of sperm chromatin hydration.
authors.affiliation: Department of Physics, University of California, Berkeley 94720.
authors.forename: L B
authors.initials: LB
authors.lastname: Da Silva
authors.forename: J E
authors.initials: JE
authors.lastname: Trebes
authors.forename: R
authors.initials: R
authors.lastname: Balhorn
authors.forename: S
authors.initials: S
authors.lastname: Mrowka
authors.forename: E
authors.initials: E
authors.lastname: Anderson
authors.forename: D T
authors.initials: DT
authors.lastname: Attwood
authors.forename: T W
authors.initials: TW
authors.lastname: Barbee
authors.forename: J
authors.initials: J
authors.lastname: Brase
authors.forename: M
authors.initials: M
authors.lastname: Corzett
authors.forename: J
authors.initials: J
authors.lastname: Gray
mesh_terms: D000818:Animals; D002458:Cell Fractionation; D002467:Cell Nucleus / Q000648:ultrastructure*; D002843:Chromatin / Q000648:ultrastructure; D004247:DNA / Q000648:ultrastructure; D004822:Epididymis / Q000166:cytology; D007150:Immunohistochemistry; D007834:Lasers; D008297:Male; D008853:Microscopy / Q000379:methods*; D051381:Rats; D013094:Spermatozoa / Q000648:ultrastructure*; D014965:X-Rays
chemical_list: D002843:Chromatin; D004247:DNA