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At least 577 records · Page 32Linked to original sources
PubMed1992

A study of the photoelectrical signal from human nasal cilia under several conditions.

The movement of normal human nasal cilia was analyzed. Ciliary beat was recorded by means of a phase-contrast microscope equipped with a photodetector. The electrical signal was analyzed as follows: i) a power spectrum was calculated in order to measure ciliary beat frequency (CBF), ii) the beat cycles were averaged and the standard deviation of the waveform was computed to determine signal consistency (SC), and iii) the ratio of the duration of the smooth to that of the steep part of the cycles was measured. This was done under three different conditions: 1) normal or "initial", 2) after induction of "function loss", and 3) after "salbutamol stimulation". At "function loss," the cilia beat slower and with less harmony. CBF decreased from an average of 9.0 Hz in the "initial" condition to 5.8 Hz. SC decreased from an average of 5.7 to 1.9. After "salbutamol stimulation", average CBF was partially restored to 7.7 Hz, while average SC increased to 4.4. These findings indicate that in ciliary function studies, SC, as a measure for ciliary beat harmony, may be introduced alongside CBF as a second valuable parameter. In this study we were not able to identify different phases in the signal that might be used as a third parameter to indicate the effective and the recovery stroke.

Albuterol↗
PubMed1984

Ultrastructure of human respiratory cilia: a study based on serial sections.

Ultrastructure of human respiratory cilia was studied in ultrathin serial sections and in random fields of sections. The apex of the cilium had dense gray material under the plasma membrane, where the "central" pair of tubules (often slightly eccentrically placed) and the single peripheral tubules ended. Thereafter the cilium thickened gradually about 1 micron below the apex and after that remained reasonably constant. At about 0.5 micron below the apex was a transformation zone (0.1 micron long), where both double and single peripheral tubules were seen. Dynein arms were not seen in the transformation zone but occurred approximately 0.1 micron below it. In a cilium, one peripheral double tubule was absent in the transformation zone but was seen about 0.2 micron below. This resulted in an artificial 8 + 2 pattern in a few sections. In cross sections at levels with peripheral double tubules the mean of the minor axes of the cilia was 0.198 +/- 0.009 micron (+/- SD) calculated from the serial sections of one patient. In 20 patients the variation was greater and the mean was higher: 0.210 +/- 0.042 micron (+/- SD).

Adult↗
PubMedDate not supplied

Mucous gel transport in a simulated cough machine: effects of longitudinal grooves representing spacings between arrays of cilia.

Under some conditions, such as inhalation injury, an array of longitudinal channels without cilia may be formed on the epithelial surface, affecting mucus transport in the lung during coughing. Moreover, in certain cases of the diseased state of the lung, immotile cilia remain embedded in the serous fluid and may form channels in the direction of air motion during coughing, providing a resistance-free pathway for serous layer fluid and assist in mucus clearance. To understand this phenomenon, we have conducted experiments with mucous gel simulants (MGS) in a simulated cough machine (SCM) using soap solution as a serous layer simulant (SLS). The channel structure of the airway surface was modeled by introducing bottom plates with longitudinal grooves about 10 cm long having different depths, widths and number of grooves. It was shown that mucous gel transport increases as the cross-sectional area occupied by channel grooves increases. The effects of sinusoidal constriction and mucous gel filance were also investigated in this model system. It was found that mucous gel transport increases in the constricted case (minimum gap, 3 mm, and maximum gap, 9 mm) in comparison with that in the parallel case (constriction gap of 9 mm). The effect of increasing the mucous gel filance was to decrease the transport,, as reported in previous studies.

Cilia↗
PubMed1993

Cilia-associated respiratory bacillus in wild rats in central Iowa.

Twenty-eight wild rats were live-trapped in central Iowa (USA) to estimate the prevalence of the cilia-associated respiratory (CAR) bacillus. Both light and electron microscopy were used to look for the Gram-negative, filamentous bacterium among cilia in tracheal and lung tissue sections. The organism was observed in the trachea of 20 rats with chronic respiratory disease and in the trachea of three of eight normal rats. Therefore, the organism appears to be common among wild rats in central Iowa.

Animals↗
PubMed1975

Mitochondrial origin of centrioles and cilia in some human endocrine neoplasms.

Fine structural investigation of surgically removed human pituitary and parathyroid adenomas, pheochromocytomas and bronchial carcinoids revealed a hitherto undetected sequence of events in the formation of centrioles and cilia indicating that mitochondria may serve as their progenitors. The first steps seem to be the disappearance of mitochondrial cristae and a polar accumulation of a fibrillar-granular material with a subsequent increase of electron density of the double mitochondrial membranes and deposition of more electron opaque substance within and around these procentriolar bodies. This process is followed by the disintegration of the double membranes and an asymmetrical division of the electron dense aggregate. The larger part seems to be the precursor of the primary centriole (basal body) whereas the smaller one that of the secondary centriole. Formation of centrioleand rudimentary cilium-like structures was disclosed within the unaltered mitochondrial membranes of oncocytic cells present in two pituitary adenomas and in one pheochromocytoma. Accumulation of procentriolar bodies and mature centrioles, noted in some tumors, may be due to a defect in the process of centriolo- and ciliogenesis. It is conceivable that the mitochondrial genome plays an important role in formation of centrioles and cilia.

Adenoma↗
PubMed1992

Ultrastructure of cilia in horses.

This paper presents some ultrastructural details of cilia from the ciliated tracheal epithelium of healthy horses. By using a new fixation method, the Authors were able to describe minute details, some of which have been only rarely observed in other species and mostly by means of the freeze-etch technique (i.e. electron dense particles of ciliary necklace). The Authors justify the need to investigate the ultrastructural details of cilia in various species since the minute morphological differences might be functionally significant.

Animals↗
PubMed2003

Changes in the bronchial epithelia in patients with immotile cilia syndromes.

Immotile cilia syndromes is a cause of recurrent infection of the airways and recurrent bronchopneumonias. Among the ciliary abnormalities are found changes in the structure of the microtubules, unco-ordinated ciliary movements caused by the absence of inner or outer or both dynein arms, and abnormalities of the kinetosomes and/or rete ridges. In patients with ciliary dyskinaesia bronchitis occurs early in life (during infancy) and usually has a recurrent tendency, so that bronchial biopsy is frequently undergone for diagnostic purposes. In this study we include 127 bronchial biopsies from patients (from 2 months to 49 years) unsuccessfully treated for recurrent respiratory tract infections. When performing regular diagnostic procedures on the light and electron microscopic level, we have looked for cilia abnormalities and also focused on changes within the mucosa and submucosa. The most common abnormality recorded was absence of the inner dynein arms, but in 40 cases neither of the dynein arms were present. Only a few patients had classical Kartagener's syndrome. Special attention is drawn to biopsies from elderly patients, in whom long-standing infections were followed by extensive damage to the bronchial epithelium, including even a total absence of ciliated cells. In some cases enhanced regenerative processes and some foci of squamous metaplasia were found. In two cases even foci of low-grade dysplasia were diagnosed.

Adolescent↗
PubMed2003

[The effect on cilia movement of experimental maxillary sinusitis in rabbits with different propose to ostia and mucosa].

OBJECTIVE: To investigate the effect on cilia movement of experimental maxillary sinusitis in rabbits with different dispose to ostia and mucosa. METHOD: Forty New Zealand White rabbits which had been induced experimental sinusitis were divided into 3 groups according to mucosa dispose during operation. The another two groups were divided according to different dispose ostia of maxillary sinus. Activated charcoal powder was used to test mucociliary transport (MCT) of maxillary sinus. RESULT: All data had be processed statistically. MCT of rabbits before operation were faster than that after operation and both of them were faster than the sinusitis group(P < 0.01). The difference of MCT in different propose of ostia groups was not significant(P > 0.05). CONCLUSION: It's a effective method to estimate the function of cilia using activated charcoal powder to test MCT of maxillary sinus. The function of regenerate mucosa after operation is lower than normal mucosa. The difference of MCT between ostia enlarged operation and ostia patent surgery is not significant.

Animals↗
PubMed1991

Calcium-activated chloride conductance in frog olfactory cilia.

We have measured the effects of cytoplasmic Ca2+ on the conductance of single cilia excised from frog olfactory receptor neurons. When free cytoplasmic Ca2+ is buffered at 0.1 microM, ciliary conductance is low. As Ca2+ is increased, ciliary conductance increases. Maximal conductance averages sevenfold higher than that measured in the absence of Ca2+. We estimate that the K1/2 for Ca2+ activation is 5 microM; the dose-response curve indicates some positive cooperativity of Ca2+ binding. Activation by Ca2+ is rapid and fully reversible. Most of the Ca(2+)-activated current is carried by Cl- and persists in the absence of Na+ and K+. The Cl- channel inhibitor 3',5-dichlorodiphenylamine-2-carboxylate (300 microM) reduces the Ca(2+)-activated current by 90%. Odorants induce a Ca2+ influx in some olfactory receptor neurons, but the consequences of this influx for neuronal function are not well understood. Our findings allow us to predict that a Ca2+ influx would increase the permeability of the olfactory cilia to Cl-. How this would affect the neuronal potential is uncertain, since the equilibrium potential for Cl- in olfactory receptor neurons is unknown.

Animals↗
PubMed1988

Isolated cilia and crystalloid inclusions in murine bone marrow stromal cells.

Bone marrow stromal cells, especially reticular cells and macrophages, are thought to have important functions in the hematopoietic inductive microenvironment (HIM). In order to define the details of their fine structure, the femoral bone marrow of 50 C 57 BL mice was examined by electron microscopy after fixation by vascular perfusion. Almost all the structures of the murine bone marrow stromal cells were similar to those previously reported. Murine bone marrow reticular cells had some isolated cilia (with a frequency of 6.0%) of 9 + 0 pattern in their axoneme. The murine bone marrow macrophages had crystalloid inclusions (CI) that revealed characteristic periodic substructure. These periodic structures could be classified into four types (types A-D). Type A inclusions had a rather amorphous structure and were the most common (with a frequency of 61.9%). Type B inclusions had a periodic lamellar structure oblique to the long axis of the CI itself at intervals of about 3.5 nm. Type C inclusions had a periodic lattice structure at intervals of about 3.7 nm, and were the least frequent (with a frequency of 6.0%). Type D inclusions had periodic laminated structure parallel to the long axis of CI at intervals of about 3.5 nm. Although the true significance of isolated cilia of murine bone marrow reticular cells and the periodic internal structures of CI in murine bone marrow macrophages remains unknown, they must not be ignored as only incidental findings: they may be useful to the understanding of the relationship between function and structure in future research on HIM.

Animals↗
PubMed1985

Ultrastructural abnormalities of respiratory cilia. Descriptive and quantitative study of respiratory mucosa in a series of 33 patients.

Ultrastructural abnormalities of human respiratory tract cilia have been studied in 33 patients: 21 were adults, 18 with chronic bronchitis, and 12 were children, two with situs inversus. Abnormalities, such as the lack of a few dynein arms or the loss of a peripheral doublet were observed quite frequently in both children and adults. However, congenital abnormalities associated with the "immotile cilia syndrome" were rare and were observed in only three of the children and none of the adults.

Adolescent↗
PubMed1985

Filamentous hemagglutinin and pertussis toxin promote adherence of Bordetella pertussis to cilia.

Bordetella pertussis adheres specifically to the cilia of respiratory epithelial cells. This ability to adhere is characteristic of virulent organisms. In order to define the contribution of various virulence factors of B. pertussis to the process of adherence, mutants deficient in single virulence factors were tested for the ability to adhere to rabbit cilia in vitro and in vivo. Two protective antigens were found to be critical to the process of adherence: filamentous hemagglutinin and pertussis toxin.

Animals↗
PubMed1986

[Electron microscopy studies of cilia of the bronchial tree in children with chronic bronchopulmonary diseases].

The results of an ultrastructural analysis of cilia in 30 children at the age of 11 month to 16 years are presented. Children with marked symptoms of chronic bronchitis were consciously chosen for examination. One group of 15 children was suffering from chronic bronchitis with bronchiectases. No bronchiectasis was found in the second group of 15 children with chronic bronchitis. Specific changes were more evident in the first group, whereas nonspecific changes were of equal frequency in both groups. Only in 3 patients of group I generalized specific defects could be demonstrated. In these cases mucociliary clearance was nearly not present. Ultrastructural changes of cilia in children with chronic nonspecific lung diseases enclose a wide spectrum. Compared to it generalized structural defects are rare and only in 3 cases of our study demonstrable (negative selection of a bronchological centre).

Adolescent↗
PubMed1988

Immotile cilia syndrome (primary ciliary dyskinesia) and inflammatory lung disease.

Abnormal mucociliary clearance can either be due to defects of mucus production and rheology or to abnormalities of the cilia. Ciliary dysfunction can be inherited as a genetically determined defect in axonemal structure (called the immotile cilia syndrome or primary ciliary dyskinesia) or acquired defects can result from airway injury. This article examines the defense of the lung as related to ciliary activity and addresses ways in which this activity can be modified by inflammatory mechanisms.

Cilia↗
PubMed1988

Enhancement of cilia regeneration by hormone treatment of Tetrahymena.

Regeneration of cilia of deciliated Tetrahymena was modified by hormones added to the nutrient medium; it was enhanced by serotonin (an amino-acid type substance), insulin (a polypeptide-type hormone) and prednisolone (a steroid-type hormone). Diiodotyrosine, another amino-acid type hormone, did not influence regeneration. Prednisolone, a hormone morphogenetic in mammals appeared to be the most active in regenerating cilia.

Animals↗
PubMed1986

[Changes in the structure of the cilia of the ciliated epithelium of the bronchi in Kartagener's syndrome in children].

Biopsies of bronchial mucous membrane taken from 4 children with Kartagener's syndrome and 10 children with chronic pneumonia were examined electron microscopically. Structural changes in cilia and apical parts of cells are detected in all patients with Kartagener's syndrome. Cilial changes provoked by chronic inflammatory process are shown. The importance of ultrastructural investigations of bronchial mucous membrane cilia in the understanding of pathogenesis of chronic lung conditions in children is underlined.

Adolescent↗
PubMed1986

Neuronal cilia in the embryonic thalamus and striatum of Gallotia galloti (Reptilia, Lacertidae).

Cilia are a common characteristic of the embryonic neurons of the thalamus and striated centers of Gallotia galloti from E.35. The ciliogenesis process occurs around the stages E.33 and E.34. The ciliary morphology shows no substantial variations between the different stages and the ciliary structure in the embryonic period is 8 + 1. On the other hand, the adult cilia has a 9 + 2 arrangement of microtubules. We do not rule out the possibility of other axonemes.

Animals↗
PubMedDate not supplied

Apical structure of human respiratory cilia.

The apical structure of human respiratory cilia was studied using thin and thick sectioning techniques. The distal end of the mature cilium is narrowed and presents dense material and a crown-shaped glycocalyx. The crown is composed of three to seven bristles, having a mean length of 31 nm and showing a periodic structure. The capping structure of the apical part of human respiratory cilia is composed of a plate and an electron-dense cap tightly bound to the central and to each of the nine peripheral A microtubules. Lateral spokes link the peripheral microtubules to the internal ciliary plasma membrane and dense filaments radiate from the dense cap to the ciliary crown. These ciliary apical structures may be involved in several functions associated with microtubule assembly as well as ciliary movement and mucociliary transport.

Adolescent↗