Proteases and Protease Inhibitors in Immune Complex Otitis Media in Chinchillas

Using an immune complex–induced (IC) otitis media model in chinchillas sensitized with human serum albumin (HSA), we measured the levels of protease activity, protease inhibitors, and HSA in the middle ear fluid (MEF). The effect of a corticosteroid agent (triamcinolone) on the degree of IC otitis media also was studied. The levels of protease inhibitors α1-antitrypsin and α2-macroglobulin in the MEF were significantly higher than in nonsensitized animals. Fibrinolytic (plasminogen activator [PA]) activity was detected in the MEF; however, only a small level of activity of nonspecific proteases was detected because of the significant level of antitryptic activity in the MEF. The levels of protease inhibitors and PA activity were significantly reduced by the steroid treatment. It is concluded that protease inhibitors play an important role in the protection of the middle ear mucosa and that corticosteroid treatment can reduce the severity of IC otitis media.

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Acute Suppurative Otitis Media

PEDIATRICS ◽

10.1542/peds.56.2.285 ◽

1975 ◽

Vol 56 (2) ◽

pp. 285-294

Author(s):

D. Stewart Rowe

Keyword(s):

Otitis Media ◽

Middle Ear ◽

Pathogenic Bacteria ◽

Acute Otitis Media ◽

Polymorphonuclear Cells ◽

Secretory Otitis Media ◽

Middle Ear Mucosa ◽

Suppurative Otitis Media ◽

Middle Ear Fluid ◽

Purulent Fluid

Most pediatricians recognize and treat acute otitis media several times each day. Yet there is wide disagreement about certain aspects of its diagnosis and treatment, despite a large and growing literature on the subject. This review attempts to summarize what is known about acute otitis media in children. DEFINITION Acute suppurative otitis media is distinguished from secretory (serous) otitis media by the presence of purulent fluid in the middle ear. Pathogenic bacteria may be cultured from the majority of needle aspirates of this purulent fluid. In secretory otitis media, relatively few polymorphonuclear cells are present in the middle ear fluid, which is either thin and straw-colored (serous) or thick and translucent grey (mucoid). The fluid has the chemical characteristics either of a transudate of plasma or of a mucoid secretion, presumably produced by goblet cells and mucous glands which are greatly increased in the middle ear mucosa of patients with secretory otitis media. Cultures of this middle ear fluid are usually negative for pathogenic bacteria and viruses. Suppurative otitis media can be diagnosed positively only by aspiration of purulent fluid from the middle ear, but this procedure is rarely necessary for initial diagnosis and management. Clinical findings helpful in distinguishing suppurative from secretory otitis media are discussed below. INCIDENCE In a study of 847 British children during the first five years of life, 19% had at least one episode of otitis media; one third of these had more than one episode. This was considered to be a minimal estimate in these children, since otorrhea was the chief criterion for diagnosis.

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Protease Inhibitors in Middle Ear Effusions from Experimental Otitis Media with Effusion: Kinetics of α1-Antitrypsin and α2-Macroglobulin Levels

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948909800410 ◽

1989 ◽

Vol 98 (4) ◽

pp. 287-292 ◽

Cited By ~ 4

Author(s):

Yukiyoshi Hamaguchi ◽

Steven K. Juhn ◽

Yasuo Sakakura

Keyword(s):

Otitis Media ◽

Middle Ear ◽

Otitis Media With Effusion ◽

Binding Activity ◽

Middle Ear Mucosa ◽

Functional Assays ◽

Α2 Macroglobulin ◽

Alpha 1 Antitrypsin ◽

Serous Otitis Media ◽

Kinetics Of

Alpha 1-antitrypsin (α1-AT) and alpha 2-macroglobulin (α2-M) were measured by both immunochemical and functional assays in paired plasma and middle ear effusions (MEEs) from experimental otitis media models (serous otitis media [SOM], purulent otitis media [POM], and SOM + POM). The MEE/plasma ratio of α1-AT in SOM was significantly higher than that in POM (p< .01) because of the high α1-AT level in POM plasma. The ratio of both antitryptic activity and trypsin-binding activity in POM was significantly higher than that in SOM + POM (p< .01, < .05), and significantly lower than that in SOM (p< .01). The majority of both inhibitors in SOM exist as the free state, and the reaction between proteases and inhibitors in POM and SOM + POM is more active than that in SOM. It is concluded that both α1-AT and α2-M appear to play an important role in the protection of middle ear mucosa by forming protease-inhibitor complexes to reduce proteolytic damage in POM and SOM + POM models.

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Middle ear fluid histamine and leukotriene B4 in acute otitis media: effect of antihistamine or corticosteroid treatment

International Journal of Pediatric Otorhinolaryngology ◽

10.1016/s0165-5876(02)00372-5 ◽

2003 ◽

Vol 67 (3) ◽

pp. 221-230 ◽

Cited By ~ 21

Author(s):

David P McCormick ◽

Kokab Saeed ◽

Tatsuo Uchida ◽

Constance D Baldwin ◽

Ronald Deskin ◽

...

Keyword(s):

Otitis Media ◽

Middle Ear ◽

Acute Otitis Media ◽

Corticosteroid Treatment ◽

Leukotriene B4 ◽

Media Effect ◽

Middle Ear Fluid

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IMPACT OF PCV7/PCV13 ON COMPLEX OTITIS MEDIA (OM) EPISODES SUBMITTED FOR MIDDLE EAR FLUID (MEF) CULTURE: COMPARISON BETWEEN TYMPANOCENTESIS AND SPONTANEOUS PERFORATION

10.26226/morressier.5731f0d3d462b8029237ff8f ◽

2016 ◽

Author(s):

S. BEN-SHIMOL

Keyword(s):

Otitis Media ◽

Middle Ear ◽

Spontaneous Perforation ◽

Middle Ear Fluid

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Air Conduction Thresholds and Secretory Otitis Media: A Conventional and Extra-High Frequency Audiometric Comparison

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948909801003 ◽

1989 ◽

Vol 98 (10) ◽

pp. 767-771 ◽

Cited By ~ 11

Author(s):

Iain W. S. Mair ◽

Oddbjørn Fjermedal ◽

Einar Laukli

Keyword(s):

Otitis Media ◽

Middle Ear ◽

High Frequency ◽

Pure Tone ◽

Low Frequency ◽

Secretory Otitis Media ◽

Middle Ear Fluid ◽

Ventilation Tubes ◽

Air Conduction

A comparison has been made of air conduction threshold changes up to 1 year after myringotomy, aspiration of middle ear fluid, and insertion of ventilation tubes in ten patients with bilateral and 12 with unilateral secretory otitis media (SOM). Pure tone air conduction thresholds have been analyzed in three frequency groups: Low frequency (LF; 0.25, 0.5, and 1 kHz), high frequency (HF; 2,4, and 8 kHz), and extra-high frequency (EHF; 10, 12, 14, and 16 kHz). In the LF and HF ranges, significant improvement came during the first 24 hours after intubation, while in the EHF range, threshold lowering occurred gradually over the following 2 months. Possible explanations for these findings are discussed.

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