Ultrastructure of Mucous Blanket in Otitis Media with Effusion

1988 ◽  
Vol 97 (3) ◽  
pp. 313-317 ◽  
Author(s):  
Masashi Inagaki ◽  
Yasuo Sakakura ◽  
Yuichi Majima ◽  
Takeshi Shimizu ◽  
Kotaro Ukai

We used transmission electron microscopy to study the mucous blanket of the promontory from children with otitis media with effusion. The vast majority of the epithelial cells were secretory, and the rest were ciliated. The mucous blanket consisted of the electron-lucent periciliary fluid and the mucous layer. In the mucous layer, two layers were identified: An inner layer with migrating cells, and an outer layer with specks. Moreover, there was a lucent zone over the nonciliated surface that was as high as the microvilli. The thickness of the periciliary layer was predominantly as great as that of the ciliary tips, which just make contact with the mucous layer; however, the mucous layer occasionally penetrated into the periciliary space. These findings indicated that there is a mucociliary dysfunction in the middle ear caused by a decrease in the number of ciliated cells, and an abnormal interaction between cilia and mucus that would interfere with ciliary movement. Thus, such a system would fail to transport the mucous blanket.

1986 ◽  
Vol 94 (3) ◽  
pp. 339-343 ◽  
Author(s):  
Roberto Gamoletti ◽  
Paola Poggi ◽  
Mario Sanna ◽  
Carlo Zini

The ultrastructural appearance of the regenerated middle ear mucosa—found at the second operation of staged intact canal wall tympanoplasty (ICWT) with mastoidectomy—has been evaluated with the transmission electron microscope. The regenerated epithelium showed all the morphologic characteristics of the normal middle ear mucosa: ciliated cells, noncillated cells, and secretory cells. All of these (Including goblet cells) have been found in the specimens. It is concluded that a normal middle ear mucosa regenerates to cover all denuded bone surfaces after the first operation of staged ICWT with mastoidectomy, when silicone rubber sheeting has been used to prevent adhesions and maintain an air-containing middle ear space.


1984 ◽  
Vol 62 (6) ◽  
pp. 1059-1066 ◽  
Author(s):  
Barbara M. MacKinnon ◽  
Michael D. B. Burt

The mature spermatozoa from Bothrimonus sturionis (Pseudophyllidea), Pseudanthobothrium hanseni (Tetraphyllidea), and Monoecocestus americanus (Cyclophyllidea) were examined using transmission electron microscopy. Transverse sections of the sperm of B. sturionis indicate that the number of sperm axonemes varies from one to eight, with approximately one-third of the sperm containing two axonemes. Likewise, the number of peripheral microtubules lying just within the external plasma membrane varies from 12 to 20. The nucleus is electron lucent and fibrous in appearance. The spermatozoa of B. sturionis show great variation in the material examined and the majority of them are believed to be aberrant. The spermatozoon of P. hanseni contains a single axoneme with the nucleus wrapped in a crescent around it in the anterior region of the sperm. The posterior portion of the spermatozoon is characterized by a helical flange which projects from the main body of the sperm. The spermatozoon of M. americanus is elongate and slender, containing a single axoneme with an electron-dense nucleus coiled around it in the anterior one-third of the sperm. Electron-opaque bodies, which may be glycogen, fill the cytoplasm. The spermatozoa of all three species contain neither an acrosome nor mitochondria. The flagella of all the spermatozoa have a 9 + "1" arrangement of microtubules. The importance of the ultrastructure of spermatozoa in the phylogeny and taxonomy of cestodes is discussed.


1992 ◽  
Vol 101 (5) ◽  
pp. 395-402 ◽  
Author(s):  
Timothy T. K. Jung ◽  
Young Min Park ◽  
David Panossian ◽  
Douglas Weeks ◽  
Stanley K. Miller ◽  
...  

Our previous studies revealed that injury to the ciliated cells of the eustachian tube may be the primary cause of irradiation-induced serous otitis media. The purpose of this study was to investigate the effects of the radioprotector WR2721 on irradiation-induced injury to ciliated cells of the eustachian tube (ET) in chinchillas. Twelve chinchillas were divided into two groups: the control group and the experimental group, which was pretreated with a single intraperitoneal dose of the radioprotector S-2-[3-aminopropylamino]ethylphosphorothioic acid (WR2721) 400 mg/kg. The two groups were exposed to 30 Gy of 13-MeV electrons in a single fraction to the area of the bullae and nasopharynx. Ciliary dysfunction was tested and ciliated cells of the ET were examined by scanning and transmission electron microscopy. Pretreatment with WR2721 was found to protect ciliated cells of the ET from irradiation injury.


1992 ◽  
Vol 106 (2) ◽  
pp. 111-115 ◽  
Author(s):  
Lars-Eric Stenfors ◽  
Simo Räisänen

AbstractEpithelial cells were obtained by swabbing the posterior wall of the nasopharynx (NPH) of 15 patients (age one to 6 8/12; years; eight males, seven females) undergoing ENT-surgery under general anaesthesia for otitis media with effusion (OME). Individually matched, ear healthy children served as controls. Bacteria attached to the non-ciliated cells were calculated according to a method described. Furthermore, quantitative and qualitative bacteriological analyses were performed on samples obtained from mucoid middle ear effusion material as well as from the NPH. All patients and controls harboured middle ear pathogens (S. pneumoniae, H. influenzae, B. catarrhalis, or S. aureus) in the NPH. Only 33 per cent of the patients harboured middle ear pathogens in the middle ear effusion and the same pathogen was invariably found in the corresponding NPH Attachment of bacteria to the non-ciliated cells of the NPH diminished significantly with growing age in the ear healthy control group but not in the OME group. OME is closely correlated tothe presence of middle ear pathogens in the NPH and to attachment of bacteria to the epithelial cells in the NPH.


2006 ◽  
Vol 51 (4) ◽  
Author(s):  
Larisa Poddubnaya ◽  
David Gibson ◽  
Zdzisław Świderski ◽  
Peter Olson

AbstractIn the spathebothriidean tapeworm Didymobothrium rudolphii (Monticelli, 1890) the fine structure of the vitellocytes at different stages of their development within the vitelline follicles, vitelline ducts and uterus was studied for the first time using transmission electron microscopy. The vitellocyte inclusions of D. rudolphii are shell globule clusters containing tightly packed shell globules associated with a matrix of moderate electron density, glycogen granules, large electron-lucent lipid droplets (up to 3 μm in diameter), and, occasionally, a lipid droplet may occur in the nucleus of the vitellocytes. The diameter of the clusters ranges from 0.4 to 2.5 μm, the number of shell globules in the clusters varies from 8 to 45, and the size of the globules ranges from 0.12 to 0.25 μm and they are of approximately homogeneous sizes within a cluster. Most vitellocyte lipid droplets have a heterogeneous configuration with a ‘cavity’ inside them when they are within vitelline ducts and intrauterine eggs. Vitellocytes of the eggs contain dark concentric bodies and lipid droplets. The interstitial tissue has a syncytial structure. The morphological parameters of the diameter and shape of shell globule clusters, arrangement of shell globules in clusters, number and diameter of globules within clusters, types of lipid droplets and presence of dark concentric bodies are compared with those of two other spathebothriidean genera, Cyathocephalus and Diplocotyle. The comparative data demonstrate that vitelline material morphology has unique features in three spathenothriidean genera and may be used as evidence for the recognition of separate taxa.


2020 ◽  
Vol 287 (1930) ◽  
pp. 20200301
Author(s):  
Chenyang Cai ◽  
Erik Tihelka ◽  
Yanhong Pan ◽  
Ziwei Yin ◽  
Rixin Jiang ◽  
...  

Structural colours, nature's most pure and intense colours, originate when light is scattered via nanoscale modulations of the refractive index. Original colours in fossils illuminate the ecological interactions among extinct organisms and functional evolution of colours. Here, we report multiple examples of vivid metallic colours in diverse insects from mid-Cretaceous amber. Scanning and transmission electron microscopy revealed a smooth outer surface and five alternating electron-dense and electron-lucent layers in the epicuticle of a fossil wasp, suggesting that multilayer reflectors, the most common biophotonic nanostructure in animals and even plants, are responsible for the exceptional preservation of colour in amber fossils. Based on theoretical modelling of the reflectance spectra, a reflective peak of wavelength of 514 nm was calculated, corresponding to the bluish-green colour observed under white light. The green to blue structural colours in fossil wasps, beetles and a fly most likely functioned as camouflage, although other functions such as thermoregulation cannot be ruled out. This discovery not only provides critical evidence of evolution of structural colours in arthropods, but also sheds light on the preservation potential of nanostructures of ancient animals through geological time.


Holzforschung ◽  
2001 ◽  
Vol 55 (4) ◽  
pp. 373-378 ◽  
Author(s):  
Adya P. Singh ◽  
Geoffrey Daniel

Summary Transmission electron microscopy (TEM) of the walls of Picea abies axial tracheids showed the distribution of lignin in the S2 layer to be inhomogenous. At relatively low magnifications, some parts of the outer and inner S2 layer appeared more electron dense than the mid region in the tracheids which were in contact with or in proximity to a ray. At similar magnifications, the presence of radial and tangential features was observed in the S2 layer of the tracheids which were in contact with or close to rays as well as in those which occurred elsewhere. Higher magnification views showed the S2 layer to be differentiated into electron lucent and dense regions in both radial and tangential directions. A comparison of the counts made of lignin particles in these regions suggested that the differentiation of the S2 wall into lucent and dense regions resulted from inhomogenous distribution of lignin observable at a nano level.


1998 ◽  
Vol 118 (2) ◽  
pp. 165-173 ◽  
Author(s):  
John F. Biedlingmaier ◽  
Anna Trifillis

CT scans of eight nonsmoking patients with chronic sinusitis and two controls were graded for their disease severity (from 0 to IV) with the classification system proposed by May. Subsequently, endoscopically harvested middle turbinate specimens from these patients (16 diseased turbinates, 4 controls) were evaluated both by scanning and by transmission electron microscopy. As the severity of the disease increased as demonstrated by CT scan, electron microscopy of 5 × 3 × 0.05 mm mucosal specimens demonstrated that the number of ciliated cells decreased whereas the number of goblet and squamous cells increased. As the disease progressed to stages III and IV, scanning and transmission electron microscopy demonstrated areas of squamous metaplasia and areas completely denuded of epithelium. The increased goblet cell population, the loss of cilia and ciliated cells, and the patches of denuded epithelium may account for the recurrent bacterial infections and chronic nasal drainage seen in patients with chronic sinusitis. The extensive mucosal changes that occur in grade III and IV disease are similar to those occurring in cigarette smokers, and it takes years to recover after discontinuation of smoking. Delayed recovery of the mucosal epithelium may account for both the recurrent infections and the slower response to treatment on the part of patients with extensive grade III and IV changes on the CT scan.


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