A laboratory-maintained colony of English springer spaniel dogs heterozygous for a putative autosomal recessive immotile-cilia syndrome (ICS) has been studied. Matings between dogs thought to be heterozygous for ICS resulted in 22 pups, five (three males and two females) of which were homozygous for ICS. Four of the five ICS-affected dogs had chronic rhinitis and bronchopneumonia. The other dog had a serious nasal discharge and died at 10 days. Four dogs had situs inversus totalis (kartagener syndrome), and the two males of reproductive age were azoospermic. In the two ICS dogs studied for ciliary function, in vivo mucociliary clearance was absent, and in vitro ciliary beat was rarely observed and of low frequency. Scanning and transmission electron microscopy disclosed the same lesions in respiratory cilia from all dogs with ICS, including random orientation and partial outer dynein arm deficiency. Four of five dogs with ICS had dilated lateral ventricles. One female pup with neonatal rhinitis and bronchopneumonia, situs solitus, and dilated lateral ventricles was presumed to be homozygous for ICS, but died without functional or structural confirmation of defective respiratory cilia. An autosomal recessive mode of inheritance for the ciliary defects and respiratory signs of ICS in these dogs is proposed.

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Ciliated epithelial cell outgrowths from canine tracheal explants were used to study the interaction between Bordetella bronchiseptica and canine respiratory cilia. A sensitive system for quantitating the ciliary beat frequencies of an individual cell was used to study the effects of B. bronchiseptica on ciliary function. Phase I and intermediate-phase B. bronchiseptica isolates produced significant reductions (greater than or equal to 50%) in ciliary beat frequencies within 5 min and nearly complete ciliostasis within 3 hr. A rough-phase isolate of B. bronchiseptica and heat- and formalin-killed preparations of the phase I isolate had no ciliostatic effect. Phase I and intermediate-phase isolates attached to cilia, whereas the rough-phase isolate did not. The ciliostatic effects of the phase I isolate could not be reproduced with endotoxin or culture supernatants from the organism. Thus, attachment alone does not produce ciliostasis; ciliostatic effects of Bordetella may require the close association between metabolically active organisms and cilia.

The macronuclei of synchronously dividing mass cultures of Tetrahymena pyriformis (strain WH6) were examined with the electron microscope for changes during two division cycles. Samples were prepared at 30-minute intervals for a period of 81/~ hours which included the time required to induce synchrony by five heat shocks (41/~ hours). The interphase macronucleus contains peripheral, crescent-shaped nucleoli and evenly distributed chromatin bodies. Centrally located RNA bodies, composed of fibers, appear 1 to 2 hours following the initial heat shock. They are completely destroyed with ribonuclease whereas the nucleoli are only partially so. Following the third heat shock the RNA bodies move to the periphery and disintegrate; the nucleoli aggregate and form blebs which protrude into the cytoplasm where they appear to pinch off and may contribute to the cytoplasmic ribonucleic acid. Cytokinesis does not occur at this time. Instead the nuclear events are repeated during the 4th and 5th hours, even though the heat shocks are terminated at 41/~ hours. Cytokinesis takes place at about 6 hours. The second division occurs about 21/~ hours later during which all the macronuclear events noted above are repeated.

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A new chemical, Peldri II, is evaluated as a compound for drying soft biological tissues for scanning electron microscopy. Peldri II, a fluorocarbon, is a solid at room temperature and is a liquid above 25 degrees C. Cells or tissues are embedded in Peldri II by immersing them in the liquid form and allowing it to solidify. Once solidified, Peldri II will sublime with or without vacuum to dry tissues, probably without introducing surface tension. Several types of cells and tissues have been examined to compare preservation with Peldri II and critical point drying techniques. No differences were detected between the two techniques when normal surface structures were examined. Peldri II appears to be a significant improvement over hexamethyldisilazane as a drying agent for scanning electron microscopy. It is also very convenient for drying large numbers of samples.