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At least 703 records · Page 39Linked to original sources
PubMed1988

Steady-state kinetic study on the inhibition of the adenosinetriphosphatase activity of dynein from Tetrahymena cilia by glycerol.

The characteristics of glycerol-induced inhibition of the dynein ATPase extracted from Tetrahymena cilia were investigated. Fifty percent inhibition was observed at about 15% (v/v) glycerol with the 22S dynein Mg-ATPase. Ethylene glycol was equally inhibitory, while sucrose, a kind of polyol, was less effective. The glycerol-induced inhibition of the 22S dynein Mg-ATPase was not influenced by pH or by raising the ionic strength of the assay solution. An aqueous glycerol solution treated with anion or cation exchanger or charcoal was equally inhibitory to a non-treated solution. The inhibition was most likely to be due to glycerol or ethylene glycol itself, not to a contaminant. The inhibition of the 22S dynein Mg-ATPase was apparently noncompetitive: only the Vmax was reduced without a significant change in the apparent Km. The dynein ATPase is known to be inhibited potently by vanadate. Glycerol reduced the sensitivity of the dynein ATPase to the vanadate-induced inhibition. Glycerol exhibited a decelerating effect on the rate of the oxygen exchange between phosphate and water catalyzed by 22S dynein in the presence of ADP and Mg2+. If it is assumed that the rate constants of the ATP hydrolysis step are not affected by glycerol, it may be implied that the phosphate release from the E.ADP.P1 intermediate was decelerated by glycerol and that the deceleration of the phosphate release paralleled the reduction of the overall ATPase activity over a wide range of glycerol concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphatases↗
PubMedDate not supplied

Situs inversus in homozygous mice without immotile cilia.

Mice homozygous for the mutation situs inversus, iv, are characterized by situs inversus in 50 percent of the individuals. We have investigated the ultrastructure and motility of tracheal cilia and sperm tails in homozygous individuals with and without situs inversus. We found no abnormalities of ciliary structure. Therefore, ciliary immotility is not an essential correlate of situs inversus.

Animals↗
PubMed1999

Toluene diisocyanate colocalizes with tubulin on cilia of differentiated human airway epithelial cells.

Toluene diisocyanate (TDI), a highly reactive industrial chemical with widespread use in the manufacture of polyurethane and plastics, is the leading cause of occupational asthma associated with chemical exposure. We report the effects of TDI vapor (20, 100, 500, 1000 ppb) in vitro on differentiated human bronchial epithelial cells. Increased mucus was observed by electron microscopy at all TDI concentrations. Cytotoxicity, as evidenced by cell pyknosis and DNA fragmentation, was detected following a 30-min exposure to TDI concentrations of 100 ppb or higher. At 1000 ppb, transepithelial resistance was lost. Using confocal microscopy and double staining, TDI was found colocalized with ciliary tubulin in cultures that had been exposed to 20 and 100 ppb. These findings are the first to identify TDI binding to human pulmonary epithelial cells and indicate extensive binding to the cilia of differentiated epithelial cells. The in vivo implications of these findings include decreased ciliary movement and longer retention of TDI and hence increased exposure. Altered cytoskeletal-derived signal transduction may be a consequence of tubulin involvement. The effects of such changes on respiratory sensitization remain to be explored.

Bronchi↗
PubMed2006

Scanning electron microscopy of ciliae and saccharine test for ciliary function in septal deviations.

OBJECTIVE: To investigate the difference in mucociliary clearance and surface mucosal structure of the nasal septum and lateral nasal wall in patients with and without septal deviation. METHOD: The saccharine-dye test was used to measure the mucociliary clearance time in both nasal cavities of 20 patients with nasal septal deviation (study group) and was compared with that of 30 patients without septal deviation (control group). Bilateral septal and lateral nasal wall mucosal biopsies were taken from the study group during septoplasty, and unilateral biopsies were taken from 10 of the control group. These biopsies were studied under the scanning electron microscope. RESULTS: In the study group, mucociliary clearance on the side opposite the septal deviation was significantly slower than on the other side. Mucociliary clearance on both sides of the deviated septum of the study group was significantly slower than clearance in the control group. There was no statistically significant difference in the distribution of mucosal cilia of the cavities on either side of the deviated septum in the study group, nor between the distribution in the study group and controls. CONCLUSION: Patients with septal deviation display no change in mucosal surface anatomy but have decreased mucociliary activity on both sides of the deviation, the least activity being on the side opposite the deviation.

Adolescent↗
PubMed1995

The lack of effect of benzalkonium chloride on the cilia of the nasal mucosa in patients with perennial allergic rhinitis: a combined functional, light, scanning and transmission electron microscopy study.

BACKGROUND: Controversy still exists about the effect of 0.02% benzalkonium chloride (BKC), a preservative in many nasal sprays, on human nasal epithelium in vivo. OBJECTIVE: To determine the safety of BKC by assessing its effect on the function and morphology of cilia of human nasal epithelium. METHODS: A single-centre, double-blind nasal biopsy study in 22 patients with perennial allergic rhinitis, receiving fluticasone propionate aqueous nasal spray (FPANS) containing BKC, BKC plus placebo or placebo alone for 6 weeks. Before, at two weekly intervals during treatment and 2 weeks after treatment ceased an indigocarmine saccharine transport time (ICST) was performed. RESULTS: ICST results did not significantly vary between the groups. There was no statistical relationship between the number of ciliated cells present and the treatment the patients received. Scanning and transmission electron microscopy examination showed no effects of BKC. CONCLUSION: Despite reports of its ciliostatic effects in vitro, BKC did not have such an effect when it was applied for 6 weeks (with/without fluticasone propionate) to the nasal mucosa of perennial allergic rhinitis patients in vivo.

Adolescent↗
PubMed1991

An animal investigation into the effects of tympanostomy on middle ear mucociliary function and cilia.

The effect of tympanostomy on guinea-pig middle ear mucosa with particular reference to mucociliary function and cilia was investigated. 13 guinea-pigs were used; 5 acted as the control group with no surgical intervention whilst the other 8 had perforations made in one tympanic membrane. 6 weeks later an attempt was made to measure mucociliary function in all the ears, but this was unsuccessful. However, it would appear that fashioning a perforation in the tympanic membrane causes no histological changes in this animal model.

Animals↗
PubMed1987

In vitro effect of beclomethasone dipropionate and flunisolide on the mobility of human nasal cilia.

Human nasal cilia were perfused with aqueous solutions of two corticosteroid aerosols, beclomethasone dipropionate (BPD) and flunisolide, with the main preservative of flunisolide, propylene glycol, and with placebo. The concentration used were BPD 0.1 mg/ml, 0.05 mg/ml, 0.005 mg/ml and 0.0005 mg/ml, flunisolide 0.25 mg/ml, 0.05 mg/ml, 0.025 mg/ml and 0.00025 mg/ml, and propylene glycol 20 mg/ml and 200 mg/ml. A dose-related decrease in ciliary beating frequency (CBF) was seen after perfusion with both BDP and flunisolide as well as propylene glycol. The decrease in CBF following perfusion with propylene glycol was partially reversible upon re-perfusion with medium alone, whereas the decrease seen after BDP and flunisolide was irreversible. Although previous studies have shown no adverse effect on the mucous membrane except for the areas hit by the impact of the sprays, our results suggest that caution should be taken when the dose and/or the length of treatment is considered, and that the effect of administration of these drugs on CBF in vivo needs to be investigated.

Beclomethasone↗
PubMed1997

Natural cilia-associated respiratory bacillus infection in rabbits used for elaboration of hyperimmune serum against Mycoplasma sp.

Cilia-associated respiratory (CAR) bacillus was identified in lung lesions of rabbits used for elaboration of hyperimmune serum against Mycoplasma mycoides ssp. capri (Mmc). Numerous Warthin Starry (WS) positive filamentous bacteria aligned perpendicularly to the surface of bronchial epithelial lining were observed. Immunoperoxidase staining of these bacteria was detected using a serum anti-rabbit CAR bacillus. Ultrastructural morphology corresponds to that of CAR bacilli previously reported in rabbits. The desirability of monitoring laboratory rabbits for CAR bacillus infection as part of the health programme is reinforced, especially in rabbits used for raising sera against respiratory pathogens of animal species in which CAR bacillus infection has been described. This is the first report of natural CAR bacillus infection in rabbits in Europe.

Animals↗
PubMed1998

Cilia-associated respiratory (CAR) bacillus infection in conventionally reared rabbits.

This study was designed to investigate the prevalence of Cilia-associated respiratory (CAR) bacillus infection in rabbits reared for meat production in Italy and to correlate the presence of CAR bacillus with inflammatory lesions of the respiratory tract. Seventy health, 3-month-old, New Zealand White rabbits, raised in 10 different rabbitries in Northern Italy were randomly selected at slaughter. No gross lesions were found at necropsy in any rabbit. In each animal, the trachea and lungs were sampled, fixed in 10% formalin, embedded in paraffin and stained with the Warthin-Starry method to evaluate the presence of CAR bacillus, and with haematoxylin and eosin to evaluate the presence of inflammatory lesions. CAR bacillus was present in 50 out of 70 rabbits (71.4%) with a prevalence of the infection that varied from 30% to 100% in the seven rabbitries. CAR bacillus was present both in the trachea and bronchi in 23 cases (32.8%), only in the trachea in 24 cases (34.3%) and only in the bronchi in three cases (4.3%). Inflammatory lesions were found in the trachea (22 cases, 31.4%) and the bronchi (58 cases, 82.8). There was a strong, statically significant correlation between the presence of CAR bacillus in the bronchi and bronchial inflammatory lesions (P < 0.0001). This study indicates that CAR bacillus infection is widespread in conventionally reared rabbits in Italy and that a possible correlation exists between the presence of CAR bacillus and bronchial inflammatory lesions.

Animals↗
PubMed1992

Extremely well differentiated papillary adenocarcinoma of the lung with prominent cilia formation.

We describe a 54-year-old woman with primary pulmonary adenocarcinoma showing a characteristic papillary architecture and prominent cilia formation. Immunohistochemically, the tumor cells were positive for carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA) and Leu-M1, and negative for lactoferrin and surfactant apoprotein. An ultrastructural study also indicated differentiation toward bronchial surface epithelial cells. To our knowledge, this type of neoplasm has not been reported as peripheral-type adenocarcinoma of the lung.

Adenocarcinoma, Papillary↗
PubMed1988

Biogenic amines stimulate regeneration of cilia in Tetrahymena thermophila.

Serotonin and catecholamines affect the regeneration of cilia in Tetrahymena thermophila in a dose-dependent manner: micromolar concentrations are stimulatory, whereas millimolar concentrations have little or no effect. This conclusion is based on motility measurements in regenerating cells and on ciliary counts in scanning electron micrographs. In addition, the recognition mechanism for each hormone appears to be specific and independent. Our results suggest an evolutionary link with hormonal mechanisms in multicellular eukaryotes.

Animals↗
PubMed1976

A human syndrome caused by immotile cilia.

Four subjects who produced immotile sperm were studied. In three of the subjects, who had frequent bronchitis and sinusitis, there was no mucociliary transport, as measured by tracheobronchial clearance. Electron microscopy indicated that cilia from cells of these patients lack dynein arms.

Bronchitis↗
PubMed1976

Egg transport in the rabbit oviduct: the roles of cilia and muscle.

Ciliary ovum transport through the oviductal ampulla was investigated, in vivo, by blocking smooth muscle activity. Isoproterenol eliminated rapid muscle-induced egg movements, yet the egg and its surrounding cells reached the site of fertilization within normal time limits. The role of cilia in ovum transport thus seems more important than that of the smooth muscle.

Animals↗
PubMed1963

Ependymal cilia: distribution and activity in the adult human brain.

Examination of 150 to 200 samples of the ependymal lining of the ventricles of nine adult human brains obtained 2(1/2) to 6 hours post-mortem revealed cilia in at least 20 separate sites in the four ventricular cavities. In seven of the brains ciliary motion was evident, and in two of these it was wide-spread and rapid. It seems likely that the adult human ventricular ependyma is ciliated throughout. Currents having distinct patterns are induced in the ventricles of animal brains by ciliary motion, and such currents probably exist in man. A local mechanism for the rapid movement of cerebrospinal fluid is therefore present.

Adult↗
PubMed1984

Voltage-dependent calcium channels from Paramecium cilia incorporated into planar lipid bilayers.

Two different divalent cation-selective channels from Paramecium cilia were incorporated into planar lipid bilayers. Both channels were much more permeable to divalent than univalent cations, and one of them discriminated significantly among the divalent cations. The selectivity and voltage dependence of the latter channel are comparable to those of voltage-dependent calcium channels found in a variety of cells. A combined biochemical, biophysical, and genetic study of calcium channels is now possible.

Barium↗
PubMed1985

Isolation, propagation, and characterization of a newly recognized pathogen, cilia-associated respiratory bacillus of rats, an etiological agent of chronic respiratory disease.

A Gram-negative, filamentous, rod-shaped bacillus which failed to grow in cell-free media was isolated in apparently pure culture from the bronchial scraping and washing of a laboratory rat suffering from chronic respiratory disease by inoculating embryonated chicken eggs via the allantoic route. None of the embryos died during 20 serial passages at weekly intervals. The bacillus was reisolated in embryonated eggs from cesarean-derived barrier-maintained N:SD(SD) rats 8 and 12 weeks after intranasal inoculation with 10th-passage allantoic fluid. The inoculated rats were housed in Horsfall-type units and remained free from other known respiratory pathogens, including mycoplasmas and murine viruses, throughout the study. The bacillus colonized the ciliated epithelial cells of the respiratory tract and caused a marked peribronchial infiltration and hyperplasia of mononuclear cells which progressed with time. The bacillus, ca. 0.2 micron wide by 4 to 6 micron long, stained very poorly with basic aniline dyes but was readily demonstrated with the Warthin-Starry silver technique. It was heat labile (56 degrees C for 30 min); spore forms were not observed. It withstood freeze-thawing and was successfully stored at -70 degrees C. Although no visible means of locomotion was observed with the electron microscope, a slow gliding motility, sometimes with bending and flexing of bacilli apparently adherent to the glass surface, was observed with phase microscopy. As an etiological agent of chronic respiratory disease of rats, this cilia-associated respiratory bacillus (tentatively designated the CAR bacillus) may be the first recognized gliding bacterium known to cause disease in a warm-blooded vertebrate.

Animals↗