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SOAE from the last major lizard family not yet systematically investigated, the teiids, were collected from the genera Callopistes, Tupinambis and Cnemidophorus. Although their papillae show characteristics of the family Teiidae, the papillae differ both in their size and in the arrangement of uni- and bi-directional hair-cell areas. Among these three genera, Callopistes showed few (2 or 3) SOAE peaks, whereas the other two genera showed more (up to 6 per ear). In the absence of knowledge of the tonotopic maps, however, it was not possible to clearly relate the spectral patterns to the differences in papillar anatomy, suggesting that the determinants of these patterns may be more subtle than anticipated., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The morphology of the basilar papilla of the emu was investigated quantitatively with light and scanning electron microscopical techniques. The emu is a member of the Paleognathae, a group of flightless birds that represent the most primitive living avian species. The comparison of the emu papilla with that of other, more advanced birds provides insights into the evolution of the avian papilla. The morphology of the emu papilla is that of an unspecialised bird, but shows the full range of features previously shown to be typical for the avian basilar papilla. For example, the orientation of the hair cells' sensitive axes varied in characteristic fashion both along and across the papilla. Many of the quantitative details correlate well with the representation of predominantly low frequencies along the papilla. The most distinctive features were an unusually high density of hair cells and an unusual tallness of the hair-cell bodies. This suggests that the evolution of morphologically very short hair cells, which are a hallmark of avian papillae, is a recent development in evolution. The small degree of differentiation in hair-cell size contrasts with the observation that a significant number of hair cells in the emu lack afferent innervation. It is therefore suggested that the development of functionally different hair-cell types in birds preceded the differentiation into morphologically tall and short hair cells.

The aim of the present experimental series was to provide further information on the distortion-product otoacoustic emissions (DP) of birds and contribute to a general understanding of DP generation. Basic characteristics of the DP 2f1-f2 and 2f2-f1 were measured in the ear canal of both awake and anaesthetized European Starlings and chickens. The effect of a third suppressive tone and the behaviour of the DP under anaesthesia were also studied. In general, the DP characteristics of both bird species resembled those of lizards and mammals, but first appeared at somewhat higher primary-tone levels. The best frequencies of third tones suppressing 2f1-f2 lay near the first primary tone (f1), but for 2f2-f1, the situation was more complex. Facilitation via a third tone was also seen for both DP, often at levels below those eliciting suppression. The DP 2f1-f2 disappeared completely at the onset of deep anaesthesia and recovered to its original magnitude when the anaesthesia was lightened, sometimes with a considerable delay. The compound action potential (CAP) was somewhat more sensitive to anaesthesia than the DP. Control experiments showed that the anaesthesia effect was not a result of hypoxia. Avian DP at low and intermediate sound levels are thus physiologically-sensitive manifestations of normal hair-cell function that are, in contrast to mammals, also anaesthesia-sensitive.

An anti-CD14 mAb RoMo-1 rapidly induces in human monocytes a transient oxidative burst activity as detected by chemiluminescence assay. Pretreatment of these cells with the mAb markedly suppresses the monocyte chemiluminescence response to opsonized zymosan. In addition, the antibody induces a significant increase of IL-1 production and secretion by mononuclear cells, comparable to a similar effect of rIFN-gamma or LPS. Electron microscopy demonstrates internalization of the CD14 molecules after interaction with the mAb in a characteristic receptor-like manner.