Mast cells in the pars flaccida of the tympanic membrane. A quantitative morphological and biochemical study in the rat

1983 ◽  
Vol 39 (3) ◽  
pp. 287-289 ◽  
Author(s):  
P. E. Alm ◽  
G. D. Bloom ◽  
S. Hellström ◽  
L. -E. Stenfors ◽  
L. Widemar
Keyword(s):  
Mast Cells ◽  
Tympanic Membrane ◽  
Biochemical Study ◽  
Pars Flaccida

Comparative Histology of the Tympanic Membrane and its Relationship to Cholesteatoma

1989 ◽  
Vol 98 (10) ◽  
pp. 761-766 ◽  
Author(s):  
Richard A. Chole ◽  
Kevin Kodama
Keyword(s):  
Mast Cells ◽  
Tympanic Membrane ◽  
Lamina Propria ◽  
Guinea Pigs ◽  
Pars Flaccida ◽  
Pars Tensa ◽  
Retraction Pockets ◽  
Comparative Histology ◽  
Tympanic Membranes

The purpose of this study was to determine whether anatomic differences in the tympanic membranes of various species could explain differences in the propensity to form aural cholesteatomas and retraction pockets. Tympanic membranes from humans, dogs, cats, rabbits, guinea pigs, rats, gerbils, and mice were examined histologically. The pars flaccida and pars tensa varied greatly among the species studied. The guinea pig's pars flaccida was very small and had a thin lamina propria. In contrast, the lamina propria of the rabbit and cat pars flaccida were thick. The amount of collagen, elastin, mast cells, and macrophages varied widely. The human and gerbilline tympanic membranes were anatomically dissimilar; for example, the human pars flaccida and pars tensa contained more and denser collagen than did those of the gerbil. The presence of macrophages or mast cells did not correlate with the propensity to develop cholesteatomas. Therefore, anatomic differences among these species do not explain why some develop aural cholesteatomas and others do not.

Mast Cells in the Pars Flaccida of the Tympanic Membrane

1984 ◽  
Vol 98 (sup418) ◽  
pp. 115-117 ◽  
Author(s):  
Louise Widemar ◽  
Gunnar D. Bloom ◽  
Sten Hellström ◽  
Lars-Eric Stenfors
Keyword(s):  
Mast Cells ◽  
Tympanic Membrane ◽  
Pars Flaccida

scholarly journals Human β-Defensin-1 mRNA Is Transcribed in Tympanic Membrane and Adjacent Auditory Canal Epithelium

1999 ◽  
Vol 67 (9) ◽  
pp. 4843-4846 ◽  
Author(s):  
Roald Bøe ◽  
Juha Silvola ◽  
Jinghui Yang ◽  
Ugo Moens ◽  
Paul B. McCray ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Tympanic Membrane ◽  
Middle Ear ◽  
Broad Spectrum ◽  
External Auditory Canal ◽  
Hair Follicles ◽  
Epidermal Layer ◽  
Sebaceous Glands ◽  
Pars Flaccida

ABSTRACT The external auditory canal is less susceptible to infections than the sensitive middle-ear cavity. Since recent research has provided insight to the production of potent antimicrobial peptides from various surface epithelia, we wanted to investigate whether protection of the external auditory canal in part could be explained by the production of human β-defensin-1 (HBD-1). This particular peptide is known to be constitutively expressed in various surface epithelia, such as airway, skin, and urogenital tissues. By reverse transcriptase PCR we demonstrate HBD-1 mRNA in the pars tensa and pars flaccida of the tympanic membrane and in the meatal skin. In situ hybridization studies localized the HBD-1 mRNA to the epidermal layer of these tissues. The HBD-1 transcripts were also evident in the sebaceous glands and in hair follicles of the meatal skin. In contrast, HBD-1 mRNA was not detected in the tympanal epithelium of the eardrum. The widespread presence of mRNA encoding for this broad-spectrum antimicrobial peptide in the meatal skin and tympanic membrane suggests that HBD-1 participates in the innate antimicrobial defense of the external auditory canal and middle-ear cavity.

scholarly journals Anatomical Boundary of the Tympanic Membrane Pars Flaccida of the Meriones unguiculatus (Mongolian Gerbil)

2011 ◽  
Vol 294 (6) ◽  
pp. 987-995 ◽  
Author(s):  
Magnus Von Unge ◽  
Jan A.N. Buytaert ◽  
Joris J.J. Dirckx
Keyword(s):  
Tympanic Membrane ◽  
Mongolian Gerbil ◽  
Meriones Unguiculatus ◽  
Pars Flaccida

Treatment of Tympanic Membrane Retraction with the Holmium Laser

1995 ◽  
Vol 112 (4) ◽  
pp. 512-519 ◽  
Author(s):  
Hironobu Kurokawa ◽  
Richard L. Goode
Keyword(s):  
Tympanic Membrane ◽  
Laser Treatment ◽  
Valsalva Maneuver ◽  
Laser Doppler Vibrometer ◽  
Laser Pulses ◽  
Holmium Laser ◽  
Pars Flaccida ◽  
Before And After ◽  
Temporal Bones ◽  
Tympanic Membrane Retraction

Politzerization, the Valsalva maneuver, and ventilation tube insertion are available treatments for tympanic membrane retraction. Ventilation of the middle ear cavity can correct tympanic membrane retraction in many cases, but not in all. Retraction may be localized or diffuse. This article describes experiments performed to evaluate a new method to “tighten” retracted or flaccid tympanic membranes with a holmium laser in a human temporal bone model. Ten temporal bones with mild-to-moderate retraction of the posterior superior quadrant or pars flaccida were treated with a series of laser pulses around and to the area of retraction. Umbo displacement before and after laser treatment was performed with a laser Doppler vibrometer to evaluate the effect on the acoustic function of the tympanic membrane. In all ears, the posterior superior quadrant retraction appeared to be completely corrected. Laser treatment of the posterior superior quadrant retraction produced improvement in umbo displacement below 1.0 kHz. After treatment of pars flaccida retraction, the configuration was improved a small amount; however, no increase in umbo displacement was found.

Tympanic Membrane Part II.:Pars Flaccida

1968 ◽  
Vol 66 (1-6) ◽  
pp. 515-532 ◽  
Author(s):  
D. J. Lim
Keyword(s):  
Tympanic Membrane ◽  
Pars Flaccida

scholarly journals ON THE ORIGIN OF HEPARIN

1947 ◽  
Vol 86 (2) ◽  
pp. 107-116 ◽  
Author(s):  
Jean Oliver ◽  
Frank Bloom ◽  
Carmen Mangieri
Keyword(s):  
Mast Cell ◽  
Particulate Matter ◽  
Mast Cells ◽  
Biochemical Study ◽  
Blood Stream ◽  
Cell Tumor ◽  
Mast Cell Tumors ◽  
Precursor Phase ◽  
Mast Cell Tumor ◽  
Metachromatic Granules

1. The spontaneous mast cell tumor of the dog contains heparin. 2. The cytoplasmic particulate content of the tumor mast cells varies with their anaplasia. This conclusion is based on the following findings: (a) in the immature cell of the more malignant tumor the particulate matter appeared in the living cells by phase microscopy to be composed of greyish illdefined particles or as a fine, weakly metachromatic granulation in the fixed and stained preparation; (b) in the mature cells of a relatively benign mast cell tumor, both in the living cell and in stained preparations, the particulate matter occurred in the form of discrete, dense, and strongly metachromatic granules, resembling those of the normal mast cell. 3. The heparin content was large (fifty times that of dog liver) in the growth with mature cells and only moderate (1.7 times) in that with immature cells. 4. Since there may be a great amount of greyish particulate matter (or fine stained granules) in a tumor of relatively low heparin content, it is suggested that this material represents an early or precursor phase in the development of heparin. 5. This possibility and the fact that the blood stream may be invaded by mature tumor mast cells of large heparin content without evident disturbance in the coagulability of the blood suggest the value of a comprehensive biochemical study of the heparin of mast cell tumors.

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