The anatomy of the larynx of the bowhead whale, Balaena mysticetus, and its sound-producing functions.

This study describes the morphology of the laryngeal apparatus in bowhead whales (Balaena mysticetus) with respect to respiration, deglutition, and vocalization. We also examined the intrinsic cricoarytenothyroid muscle (Musculus (M.) diverticuli laryngei) which forms the laryngeal diverticulum, to ascertain its interactions with the laryngeal cartilages during respiration and sound production.

Combustion-derived hydrocarbons localize to lipid droplets in respiratory cells.

Combustion-generated radicals interact to form polynuclear aromatic hydrocarbons (PAHs), including carcinogens. PAHs aggregate into 20- to 50-nm particles, which extend into branched-chain structures (soots). Incomplete combustion yields black soot particles and black smoke.

Spiroplasma spp. from transmissible spongiform encephalopathy brains or ticks induce spongiform encephalopathy in ruminants.

Spiroplasma, small motile wall-less bacteria, are linked by molecular and serological studies to the transmissible spongiform encephalopathies (TSEs), which include scrapie in sheep, chronic wasting disease (CWD) in deer and Creutzfeldt-Jakob disease in humans. In this study, two experiments were undertaken to determine the role of spiroplasma in the pathogenesis of TSE. In experiment 1, Spiroplasma mirum, a rabbit tick isolate that had previously been shown to experimentally induce spongiform encephalopathy in rodents, was inoculated intracranially (IC) into ruminants.

Bone formation as a potential motive force of tooth eruption in the rat molar.

The objectives of this anatomical study were to (1) determine if significant bone growth occurs in the base of the alveolar bony crypt of the first mandibular molar to move the tooth through the eruption pathway; (2) determine if the osteogenesis in the crypt correlates with the published chronological gene expression of bone morphogenetic protein-2 (BMP-2) in the dental follicle; and (3) determine chronologically and regionally the crypt bone activity. To accomplish this, the alveolar bony crypts of rat mandibular molars from postnatal days 3 to 18 were processed and examined by scanning electron microscopy (SEM). In addition, mandibles and teeth of ages 12-18 were prepared for light microscopy.

Chromosomal localization of a proinsulin transgene in Japanese quail by laser pressure catapulting.

Transgenic avian bioreactors produce therapeutic recombinant proteins in egg white. To date, however, methods for transgenic modification of the avian genome or determining transgenic status of individual birds are scarce. The dual, but interrelated, goals of this research were to: (1) develop a method of detecting stable DNA insertion into Japanese quail; and (2) provide a method for gene location on avian chromosomes.