Ciliate

Ciliates A class of protozoans distinguished by short hairs on all or part of their bodies. 

Airway cross-sections have the nominal anatomy shown in Fig. 5.16. Airway surface liquid (AST), primarily composed of mucus gel and water, surrounds the airway lumen with a thickness thought to vary from 5 to 10 mm. AST lies on the apical surface of airway epithelial cells (mostly columnar ciliated epithelium). This layer of cells, roughly two to three cells thick in proximal airways and eventually thinning to a single cell thickness in distal airways, rests along a basement membrane on its basal surface. Connective tissue (collagen fibers, basement membranes, elastin, and water) lies between the basement membrane and airway smooth muscle. Edema occurs when the volume of water within the connective tissue increases considerably. Interspersed within the smooth muscle are respiratory supply vessels (capillaries, arteriovenous anastomoses), nerves, and lymphatic vessels. 

Cilia are thin cylindrical hair-like structures with a cross-sectional radius of 0.1 gm projecting from the apical epithelial surface of ciliated columnar cells. Ciliary length is thought to correspond to periciliary fluid depth and range from approximately 7 gm in proximal airways to roughly 5 gm in more distal airways.- Each ciliated epithelial cell supports approximately 200 cilia at a density of eight cilia/gm. Short microvilli, possibly associated with secretory functions, are interspersed among the cilia. 

Nonciliated cells separate fields of ciliated epithelial cells from each other. Synchronized ciliary movement, with a beat frequency in human proximal airways under normal conditions of 8-15 EIz, propels mucus along the mucociliary escalator at a rate of up to 25 mm/min. Beat frequencies appear to slow to roughly 7 Hz in more distal airways. Cilia move in the same direction and in phase within each field but cilia in adjacent fields move in slightly different directions and are phase shifted. These beat patterns result in metachronal waves that steadily move mucus at higher velocities ( -12-18 mm/min) than would be achievable by summing the motion of individual cilia. 

Toyopearl HW-50S resin has been used to help isolate the ubiquitin-histone conjugate mH2A from the unicellular ciliated protozoan Tetrahymena pyriformis. Figure 4.49 shows the separation of mH2A from the histone, H2A. The sole difference between these two components is a small polypeptide, ubiquitin (approximately 8500 Da). The mH2A fraction was then further purified by HPLC on a Tosoh ODS-silica column (52). One of the many benefits... 

Flimmer-. ciliated, ciliary, vibrating, -messer, m. scintillometer. 

Wimperinfusorien, /.pi. (Zodl.) CiUata. wimperad, p.a. ciliated, ciliary winking. Wind, m. wind, breeze air blast. -blSser, m. 

In mammals, ciliated cells line the respiratory air passages, the fallopian tubes, and the ventricles of the brain. The cilia beat in a coordinated manner in waves that propel fluids, suspended cells, and small particles along a surface. The motility of the sperm cell is provided by a single flagellum. 

The specific microbes used depends on many factors, for example, the particular formation involved, the specific hydrocarbons in the formation, and the desired microbial action on these formation hydrocarbons. The microbes may be aerobic or anaerobic and may or may not require one or more additional nutrients (e.g., naturally ocurring or injected) to be included in the formation. Highly mobile microbes, such as flagellated or ciliated bacilli, are useful. The microbes are sized so that they are mobile in the connate water of the formation [966]. 

PI. 2.1B Amphibian AOS, surface of accessory neuroepithelium chemosensory strips divided by non-sensory ridges in lateral nasal sinus of Japanese Red-bellied Newt (iCyaops pyrrhogaster) SEM X 742, R = ridge with microvillous cells and G = groove with ciliated cells and cellular protrusions (from Jones et at., 1994). 

Hansen A., Zeiske E. and Reutter K. (1994). Microvillous and ciliated receptor cells in the olfactory epithelium of the Australian Lungfish, Neoceratodus forsteri. In Advances in Biosciences 93 (Apfelbach R., et al., eds.). Elsevier, Oxford, pp. 43-51. 

Morita Y. and Finger T. (1998). Differential projections of ciliated and microvillous olfactory receptor cells in the catfish, Ictalurus punctatus. J Comp Neurol 398, 539-550. 

Local host defenses of both the upper and lower respiratory tract, along with the anatomy of the airways, are important in preventing infection. Upper respiratory defenses include the mucodliary apparatus of the nasopharynx, nasal hair, normal bacterial flora, IgA antibodies, and complement. Local host defenses of the lower respiratory tract include cough, mucodliary apparatus of the trachea and bronchi, antibodies (IgA, IgM, and IgG), complement, and alveolar macrophages. Mucus lines the cells of the respiratory tract, forming a protective barrier for the cells. This minimizes the ability of organisms to attach to the cells and initiate the infectious process. The squamous epithelial cells of the upper respiratory tract are not ciliated, but those of the columnar epithelium of the lower tract are. The cilia beat in a uniform fashion upward, moving particles up and out of the lower respiratory tract. 

Fig. 8.4 Volvox shows different types of association of cells into loose organisation. Choanoflagellates are organisms with connected parts while Paramoecium is a highly organised, ciliated animal protozoan.

J.E. Doeller, M.K. Grieshaber, and D.W. Kraus, Chemolithoheterotrophy in a metazoan tissue thiosulfate production matches ATP demand in ciliated mussel gills. J. Exp. Biol. 204, 3755-3764 (2001). 

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