BACKGROUND Cilia are complex and powerful cellular structures of the respiratory mucosa that play a critical role in airway defense. Respiratory epithelium is lined with cilia that perform an integrated and coordinated mechanism called mucociliary clearance. Mucociliary clearance is the process by which cilia transport the mucus blanket overlying respiratory mucosa to the gastrointestinal trac...

BACKGROUND Ciliated ependymal cells line the cerebral ventricles and aqueducts separating the infected CSF from the brain parenchyma in meningitis. PRINCIPAL FINDINGS Investigation of the interaction of Listeria monocytogenes with cultured rat brain ependymal cells showed that certain strains reduced the beat frequency of the cilia but all the strains studied significantly reduced the ciliary...

The present study examined whether protein kinase C phosphorylated a ciliary protein and whether this phosphorylation event was temporally correlated with a decrease in ciliary beat frequency. Activation of protein kinase C decreased ciliary beat frequency of sheep tracheal epithelium, an effect fully blockable by pretreatment of the tissue pieces with H-7, a protein kinase inhibitor. Using cil...

Cyclic adenosine monophosphate and cyclic guanosine monophosphate are universal intracellular messengers whose concentrations are regulated by molecular networks comprised of different isoforms of the synthases adenylate cyclase or guanylate cyclase and the phosphodiesterases which degrade these compounds. In this paper, we employ a systems biology approach to develop mathematical models of the...

BACKGROUND Mucociliary clearance is impaired in patients with Young's syndrome (obstructive azoospermia with recurrent sinobronchial disease), cystic fibrosis, and primary ciliary dyskinesia. No defect of cilia or mucus has been detected in Young's syndrome. METHODS Ciliary function and ultrastructure, including ciliary orientation, were studied quantitatively in 20 patients with Young's synd...

THE mucociliary apparatus is the main defense mechanism preventing respiratory infection, removing inhaled debris and pathogens from the airways. Many critical care patients suffer from ciliary loss, reduced cilia beat frequency, and mucus clearance, which may be related to the high incidence of nosocomial respiratory infections within intensive care. It is often necessary to use an increased f...

An examination is made of the hypothesis that endogenous 5-hydroxytryptamine (5-HT) serves as a local hormone regulating ciliary activity in the lamellibranch gill. These cilia are sensitive to exogenous 5-HT and respond to it by a prompt, sustained, and reversible rise in beat frequency; at the same time the carbohydrate metabolism is stimulated, as described elsewhere. Control gill contains s...