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E H Huizing

Publications and source records attributed to E H Huizing.

At least 19 recordsLinked to original sources
PubMed1992

Cell membrane polarity of the epithelial cells in the endolymphatic sac of the guinea pig.

The epithelial cells of the endolymphatic sac (ES) were studied in order to characterize their glycocalyx composition. Colloidal thorium and cationized ferritin were used as electron-dense markers to visualize the glycocalyx as well as the basement membrane. In addition, enzymatic digestions were performed to identify the reactive components of the glycocalyx responsible for colloidal thorium labeling. The results indicate that the glycocalyx of the ES epithelial lining is very rich in sialic acid. Furthermore, a marked polarity in glycocalyx reactivity is present between the apical and basolateral membranes, whereas difference in glycocalyx reactivity between the light and the dark cells are not obvious. We speculate that the specific composition and the apparent polarity of the ES epithelial cell glycocalyx are of importance to the equilibrium of electrolytes in the ES lumen.

Animals↗
PubMed1992

Expression of intermediate filament proteins in the adult human vestibular labyrinth.

The immunohistochemical detection of intermediate filament proteins, cytoskeletal constituents that allow the characterization of tissues, was investigated in frozen sections of the chemically fixed, nondecalcified, adult human vestibular labyrinth. Cytokeratins (CKs) were detected in all epithelia (including the sensory epithelia), although substantial differences in the degree of staining between individual cells occurred. The expression of CKs 7, 8, 18, and 19 as detected with our subunit-specific monoclonal antibodies in the vestibular epithelia is typical of "simple" epithelia and is identical to the CK subtypes found in the human cochlea. Although immunostaining for CK 7 was very weak and was limited to certain vestibular wall cells, the other CKs demonstrated a pronounced and rather uniform distribution throughout the different epithelia. All epithelia (including the sensory epithelia) displayed expression of vimentin, thus demonstrating co-expression with CKs. Vimentin was also present in the subepithelial connective tissue fibroblasts and mesothelial lining of the vestibular labyrinth. Neurofilament proteins were detected in all neuronal structures. The intense staining for CKs in the maculae and cristae implies that these sensory organs are rigid structures, a finding that may possibly be of importance in the mechanoelectrical transduction process for the sense of equilibrium.

Aged↗
PubMed1992

Corneal autoimmunity in Cogan's syndrome? Report of two cases.

Autoimmune reactivity against corneal antigens is described in two patients with Cogan's syndrome, a nonsyphilitic deep interstitial keratitis with vestibuloauditory symptoms. In both cases corneal antibodies were found at the beginning or during an exacerbation of the disease. After administration of high doses of corticosteroids the corneal antibodies diminished. Interstitial keratitis can generally be controlled by local or systemic corticosteroids. The effect of corticosteroid therapy on the audiovestibular symptoms is variable. The possibility of an autoimmune pathogenesis of Cogan's syndrome is discussed.

Adult↗
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↗
PubMed1992

Glycocalyx heterogeneity in normal and hydropic cochleas of the guinea pig.

The endo- and perilymphatic glycocalyx of the cochlear epithelia were investigated ultrastructurally in normal and hydropic cochleas using the electron-dense markers cationized ferritin and colloidal thorium. In the normal cochleas all epithelial surfaces showed reactivity with both markers. Using cationized ferritin, no regional differences in reactivity could be demonstrated. With colloidal thorium, however, the apical membranes of the outer hair cells reacted more intensely than either the basolateral membranes or the membranes of the supporting cells of the organ of Corti. Cationized ferritin reactivity was not affected by digestion with either neuraminidase or hyaluronidase. In contrast, colloidal thorium reactivity of the endolymphatic surfaces was greatly reduced after neuraminidase digestion. Reactivity of the cell membranes lining the perilymphatic compartments of the cochlea was less affected by neuraminidase digestion, except for the basolateral membranes of the sensory and supporting cells of the organ of Corti, which demonstrated a greatly reduced reactivity. These findings indicate that the glycocalyx of the epithelial surfaces lining the endolymphatic compartment has a high content of sialic acid. The differences that are observed in normal cochleas in regard to colloidal thorium reactivity between the apical membranes of the outer hair cells and the membranes of the Deiters' cells, could not be demonstrated in hydropic cochleas. This probably contributes to the early functional changes in outer hair cells observed in experimental hydrops.

Animals↗
PubMed1992

Influence of sympathetic and parasympathetic substances in clinical concentrations on human nasal ciliary beat.

The effect of autonomic substances on ciliary beat in mucosal biopsies from the normal human nose was studied. The influence on ciliary beat frequency (CBF) as well as on ciliary beat harmony was measured photoelectrically. The sympathetic beta-agonist isoprenaline was found to have a stimulatory effect on CBF, whereas the alpha-agonist xylometazoline reduced CBF and ciliary beat harmony. The parasympathetic agonist carbachol had a positive effect on CBF. The sympathetic antagonists timolol (beta) and phentolamine (alpha) as well as the parasympathetic antagonist atropine had no effect. The effect of the agonists on ciliary beat was absent when they were administered in combination with their specific antagonists. These experiments indicate that, in clinical concentrations, the autonomic substances modify ciliary beat by a direct effect on the ciliated cells.

Adrenergic alpha-Agonists↗
PubMed1991

Scanning electron microscopy of hair cells, stereocilia and cross-linkage systems in experimentally induced endolymphatic hydrops.

In this study scanning electron microscopy was used to examine the stereocilia and their cross-linkages in guinea pig cochleas 1, 2, 4 and 8 months after endolymphatic sac obliteration. Initial changes were restricted to the stereocilia of the outer hair cells and consisted of a disarrangement and bulging of the stereocilia with an interruption of their cross-linkage systems. Subsequently, the stereocilia became fused and atrophied. Cross-linkages of inner hair cells remained intact. Loss of both outer and inner hair cells started in the apex and progressed towards the base of the cochlea. These findings indicate that early changes in the micro-architecture of the stereocilia may have a mechanical origin, with pressure fluctuations in the scala media possibly playing an important role.

Animals↗
PubMed1991

Cytokeratin expression in the epithelia of the adult human cochlea.

Epithelia can be characterized by the specific expression pattern of their cytokeratin components. Therefore, we investigated the immunohistochemical expression of different cytokeratin subunits in frozen sections of chemically fixed, non-decalcified, adult human cochleas. The organ of Corti and the marginal cells of the stria vascularis showed reactivity for cytokeratin subunits 8, 18 and 19, whereas the other cochlear epithelia in addition expressed cytokeratin 7. The expression of cytokeratins 7, 8, 18 and 19 by the epithelia of the adult human cochlea is typical of "simple" epithelia. The deviant cytokeratin pattern of the organ of Corti and marginal cells of the stria vascularis may well reflect their differences in functional state and/or differentiation as compared to the other cochlear epithelia.

Adult↗
PubMed1991

Differential immunohistochemical detection of cytokeratins and vimentin in the surgically removed human endolymphatic duct and sac.

Immunohistochemical detection of intermediate filament proteins and different subgroups of cytokeratins (Cks) was used to characterize the epithelium of the surgically removed adult human endolymphatic duct (ED) and sac (ES). The epithelium of the ED and ES demonstrated immunostaining for Cks 7, 8, 14, 17, 18 and 19, a pattern typical of so-called "complex" or "mixed" epithelia. This is a remarkable finding, since this pattern differs strikingly from previously reported data on the adult human cochlea and vestibular labyrinth that demonstrated a Ck pattern typical of "simple" (or single-layered) epithelia. Furthermore, the epithelium of the ED and ES demonstrated co-expression of Cks and vimentin. The present data indicate that the epithelium of the ED and ES exhibits another type of epithelial differentiation and demonstrates a higher degree of complexity than the other epithelia in the adult human inner ear.

Adult↗
PubMed1991

Expression of intermediate filament proteins in the adult human cochlea.

The immunohistochemical localization of intermediate filament proteins was studied in frozen sections of chemically fixed, nondecalcified adult human cochleas. Cytokeratins were found in all epithelial cells lining the cochlear duct (including most supporting cells of the organ of Corti) but were absent in the hair cells. Neurofilament proteins were present in the nerve endings at the hair cells, in the neural bundles, and in the ganglion cells. Vimentin staining occurred in most of the supporting structures and was roughly complementary to the regions showing cytokeratin staining and neurofilament staining. However, the region of the spiral prominence and outer sulcus, as well as the pillar cells and Deiters' cells in the organ of Corti, showed coexpression of vimentin and cytokeratins. No definite immunostaining was observed with antibodies to desmin and glial fibrillary acidic protein.

Adult↗
PubMed1991

Early ultrastructural effects of gentamicin cochleotoxicity.

Ultrastructural changes in the cochlear hair cells during the early stages of gentamicin intoxication were investigated after tri-aldehyde primary fixation and OSO4/K4Ru(CN)6 post-fixation. In cochleas treated for 5, 10 and 15 days with gentamicin the individual outer hair cells (OHC1, OHC2 and OHC3) were randomly affected. Degeneration of the inner hair cells was not observed at this stage. Ultrastructurally, the earliest identifiable changes were an increase in lysosomes, proliferation of the endoplasmic reticulum, and formation of Hensen's bodies. This was followed by dilatation of the endoplasmic reticulum and the nuclear envelope, giving rise to extensive cytoplasmic vacuolation. These results demonstrate that gentamicin-induced changes primarily involve the cell's synthetic apparatus. All further intracellular changes occur at a much later stage and are therefore to be considered secondary events.

Animals↗
PubMed1991

Factors influencing ciliary beat measurements.

Investigation of the effect of environmental and pharmacological factors on human respiratory epithelium requires standardization of measuring conditions. Ciliary beat frequency (CBF) and its shift were determined photo-electrically in 43 biopsies of human nasal mucosa. Curette biopsies were compared to forceps biopsies. CBF variation between three different cells of one biopsy sample did not differ for the two biopsy techniques. The ciliated cells of forceps biopsy specimens showed a more constant beating pattern which resulted in a small CBF shift. It appeared that in studying ciliary activity a continuous layer of ciliated cells which is in contact with the basal membrane is required. Therefore forceps biopsies are preferable to curette biopsies. The environmental temperature has to remain constant since CBF is temperature dependent. The pH and osmolarity of the medium do not influence CBF when kept within a certain range. No effect of medium superfusion flow rate was seen.

Basement Membrane↗
PubMed1990

Ciliary beat frequency and the nasal cycle.

The purpose of this study was to investigate whether the ciliary beat frequency (CBF) is influenced by the nasal cycle. Nasal patency was assessed by active anterior rhinomanometry and immediately followed by measuring CBF in biopsies taken from the posterior aspect of the inferior turbinates in 22 healthy volunteers. CBF was determined in three different cells of each biopsy by means of a phase-contrast microscope and a photo-electrical cell. The signal was analyzed by a computed power spectrum. The frequency and its shift were calculated for a period of 20 s. The results were as follows: (1) no correlation was found between CBF and nasal patency; (2) CBF in one cell is constant to a high degree; (3) CBF of different cells in the same biopsy specimen varies considerably.

Adolescent↗
PubMed1990

Progress in temporal bone histopathology. III. An improved technique for immunohistochemical investigation of the adult human inner ear.

A new tissue processing technique is described for immunohistochemistry of the adult human inner ear, avoiding the immuno-compromising step of prolonged decalcification. The procedure allows reliable investigation of frozen sections of the chemically fixed, non-decalcified, adult human cochlea and vestibular sense organs. Preservation of immunoreactivity, combined with satisfying tissue morphology, is illustrated by the immunohistochemical localization of the intermediate filament constituents cytokeratins and neurofilament proteins throughout the membranous labyrinth.

Adult↗