Saccular Cells Research Articles

Inner ear impairment after stapedotomy: do the cervical vestibular evoked myogenic potentials play a diagnostic role?

Background Otosclerosis is characterized by a bony remodeling process that ends up with stapes fixation. The hearing impairment can be recovered by surgery by replacing the stapes superstructure. Due to the surgical management of the vestibule, the vestibular examination could provide an insight into the correlation between this kind of surgery and vestibular changes. Objectives To evaluate the impact of the stapedotomy on the inner ear. Methods We evaluated pure tone audiometry and the presence of vestibular evoked myogenic potentials (VEMPs) in 41 patients with otosclerosis before and after the stapedotomy operation. Results Air conduction (Ac)-VEMPs were present in 18 cases preoperatively and 31 cases postoperatively. Bone conduction (Bc)-VEMPs were present in 23 cases preoperatively and 33 cases postoperatively. ABG was closed to less than 20 dB in all cases after the operation Conclusions The preoperative Bc-VEMPS had an outstanding capability to predict the type of hearing loss. The postoperative absence of VEMPS despite the closure of ABG indicated the impact of otosclerosis on the saccular cells. The use of Thulium Laser in stapedotomy didn’t affect significantly the saccular cells. Significance Integrated use of audiometry and VEMPs was effective to evaluate the changes associated with otosclerosis and the stapedotomy operation.

Cell proliferation follows acoustically-induced hair cell bundle loss in the zebrafish saccule

Fishes are capable of regenerating sensory hair cells in the inner ear after acoustic trauma. However, a time course of auditory hair cell regeneration has not been established for zebrafish. Adult zebrafish ( Danio rerio) were exposed to a 100 Hz pure tone at 179 dB re 1 μPa RMS for 36 h and then allowed to recover for 0–14 days before morphological analysis. Hair cell bundle loss and recovery were determined using phalloidin to visualize hair bundles. Cell proliferation was quantified through bromodeoxyuridine (BrdU) labeling. Immediately following sound exposure, zebrafish saccules exhibited significant hair bundle damage (e.g., splayed, broken, and missing stereocilia) and loss (i.e., missing bundles and lesions in the epithelia) in the caudal region. Hair bundle counts increased over the course of the experiment, reaching pre-treatment levels at 14 days post-sound exposure (dpse). Low levels of proliferation were observed in untreated controls, indicating that some cells of the zebrafish saccule are mitotically active in the absence of a damaging event. In sound-exposed fish, cell proliferation peaked two dpse in the caudal region, and to a lesser extent in the rostral region. This proliferation was followed by an increase in numbers of cuticular plates with rudimentary stereocilia and immature-like hair bundles at 7 and 14 dpse, suggesting that at least some of the saccular cell proliferation resulted in newly formed hair cells. This study establishes a time course of hair cell bundle regeneration in the zebrafish inner ear and demonstrates that cell proliferation is associated with the regenerative process.

Effects on survival and mucous cell proliferation of Atlantic halibut, Hippoglossus hippoglossus L., larvae following microflora manipulation

A higher number of epidermal mucous cells was observed in Atlantic halibut ( Hippoglossus hippoglossus L.) yolk sac larvae kept in seawater from 50 m depth, containing 7.5×10 4–10.3×10 4 bacteria/ml (DAPI), as compared to larvae kept in seawater from 200 m depth with 3.3×10 4–5.0×10 4 bacteria/ml. The affected mucous cells were identified as saccular cells. The number of saccular cells was also higher in larvae kept in incubators with seawater that were supplemented with Lactobacillus plantarum (about 10 6 bacteria/ml). Thus, it appeared that the number of bacteria in the seawater could affect the proliferation of saccular cells in halibut larvae. Furthermore, survival of the halibut larvae was affected by pre-incubation of eggs and hatching larvae with different strains of commensal bacteria isolated from fish. A larval survival of 94.4% was obtained following pre-incubation with an apathogenic Vibrio salmonicida strain, whereas V. iliopiscarius sp. nov. reduced survival to 63.4% in the first 12 days, compared to 81% survival in the control group. In the same period, survival following incubation with L. plantarum was 95.8%. Survival 32 days post-hatching was significantly higher in the groups of halibut larvae pre-incubated with L. plantarum (68.4%) and V. salmonicida (72.8%), as compared to the control group (58.2%). Pre-incubation with V. iliopiscarius resulted in 41.8% survival at day 32, which was significantly lower than the control group. Thus, pre-incubation of halibut eggs and hatching larvae with strains of commensal bacteria may subsequently affect larval survival, and in the present study, an indigenous apathogenic strain closely resembling the marine pathogen V. salmonicida resulted in the highest survival.

Ontogenetic development and composition of the mucous cells and the occurrence of saccular cells in the epidermis of Atlantic halibut

An increase in the number of mucous cells of the epidermis, as well as qualitative changes of the mucus composition from predominantly neutral to a mixture of neutral and sulphated glycoproteins occurred during the development from a pelagic larva to a bottom‐dwelling flatfish. Numerous saccular cells were observed in the epidermis of the yolk‐sac larvae that disappeared simultaneously as the mucous cells increased in number in the epidermis of the metamorphosed halibut. These findings may help to understand the protective role of the mucus layer of Atlantic halibut during development as compared to other fish species in aquaculture.

Ontogenetic development and composition of the mucous cells and the occurrence of saccular cells in the epidermis of Atlantic halibut

Ontogenetic development and composition of the mucous cells and the occurrence of saccular cells in the epidermis of Atlantic halibut

Two types of sensory hair cell in the saccule of a teleost fish

Previous investigations have demonstrated significant ultrastructural differences in hair cells located in various regions of the utricle of the oscar, Astronotus ocellatus. In this study, we used TEM and SEM to examine cells from the central and marginal regions of the saccule to determine if similar hair cell ultrastructural differences exist in this endorgan. Based upon ultrastructural characteristics, central saccular cells closely resemble utricular striolar cells while marginal cells are intermediate in ultrastructure between striolar and extrastriolar cells of the utricle.

Primary vestibulocerebellar fibers in the monkey: distribution of fibers arising from distinctive cell groups of the vestibular ganglia.

AbstractIn a series of monkeys attempts were made to determine the distribution of primary vestibulocerebellar fibers arising from cell groups of the vestibular ganglia that innervate distinctive parts of the labyrinth. Lesions in the vestibular ganglia were produced by extradural surgical approaches in cell groups which innervate: (1) the cristae of the anterior and lateral canals, (2) the macula of the utricle, (3) the macula of the saccule, and (4) all receptor components of the labyrinth. In a control series selective lesions were produced in the cochlea and cochlear nerve. Vestibular and cochlear lesions were studied in serial sections of the petrous bones stained with Sudan black B. Degeneration in the brain stem and cerebellum was studied in sagittal and transverse sections stained by the Nauta‐Gygax and Wiitanen technics.Vestibular fibers projecting to parts of the cerebellum represent ascending branches of root fibers which largely traverse the superior vestibular nucleus and enter the cerebellum via the juxtarestiform body. In the cerebellum fibers divide into medial and lateral bundles. Medial branches projecting fibers to the ipsilateral nodulus, uvula (lamina d) and lingula appear to arise from cells in all parts of the vestibular ganglia. Cells in the superior vestibular ganglion (SVG) innervating the cristae of the anterior and lateral canals project fibers to floccular folia 5 to 10; the utricular cell groups of SVG projects fibers mainly to floccular folia 5 and 6 while the saccular cell group of the inferior vestibular ganglion (IVG) projects fibers to floccular folia 3, 4, 5 and 6. Collaterals of fibers passing laterally in the peduncle of the flocculus end in ventromedial parts of the dentate nucleus.Some vestibular fibers projecting to parts of the flocculus penetrate the entire thickness of the granular layer and break up into fragments near Purkinje cells and in basal parts of the molecular layer. Such fibers appear to represent climbing fibers.Cochlear lesions produce degeneration in localized regions of the ipsilateral dentate nucleus.Cell groups of the vestibular ganglia innervating different receptor components of the labyrinth have unique areas of predominant projections in different folia of the flocculus and common regions of termination in portions of the nodulus and uvula.

Histochemistry of the epithelial mucins in the alimentary tract of the snail Marisa cornuarietis

AbstractA histochemical study of the mucus‐secreting cells in the epithelial lining of the alimentary tract of the ampullariid snail Marisa cornuarietis permits description of six types of glandular cells secreting carbohydrate‐rich substances. These mucous cells are designated on morphological grounds as fusiform, club‐shaped, ovate, goblet, saccular and elongated conical and their histology together with their distribution and relative frequency in the different organs is described.Histochemical analysis using various fixatives and numerous recently‐developed histochemical techniques shows that four main types of mucosubstances are produced by the six cell types. (1) The fusiform and club‐shaped cells secrete neutral mucosubstances with moderate‐to‐weak PAS reactivity and variable amounts of basic protein. (2) The ovate cells secrete a strongly PAS‐reactive, neutral mucosubstance lacking associated basic protein. (3) The goblet and saccular cells elaborate predominantly PAS‐unreactive, strongly acidic, and highly sulfated mucosubstances or sulfomucins. (4) The elongated‐conical cells secrete a highly PAS‐reactive, weakly acidic sulfomucin whose vic‐hydroxyls are presumably located in close proximity to sulfate esters.