Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bony tissues are integral parts of the function of the middle ear and the protection of adjacent vital structures. To explore the reaction of middle ear bone to acute otitis media, rats were challenged with Streptococcus pneumoniae and Haemophilus influenzae. Local changes were monitored for up to 1 month. After reverse transcription, competitive polymerase chain reaction was used to determine the expression levels of two molecular markers of bone formation, osteocalcin and procollagen I, and the two cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha, in the bone. Middle ear bone responded rapidly to bacterial challenge, and the reaction depended upon the causative agent. On day 1, IL-6 and TNF-alpha transcripts were detected in the bone from all middle ears. After a short period of decreased expression of osteocalcin, during which the otitis diagnosis could not be made clinically, the levels of bone formation markers increased dramatically. The maximum levels of these markers were reached on days 6 and 14 for animals challenged with H. influenzae and pneumococci, respectively. Infections induced by pneumococci had a longer duration, and after the initial phase the production of osteocalcin and procollagen transcript were significantly higher in the pneumococcus-infected animals. The results indicate that even in an uncomplicated infection, the bone of the bulla reacts to an acute otitis media with a short period of inhibited osteoblast activity followed by a longer period of new bone formation.
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PMID:Expression of molecular markers for bone formation increases during experimental acute otitis media. 1127 36

There are indications that bone regulatory and immune systems are closely related. Of special interest in this context is the acute otitis media (AOM), which mainly affects immunologically immature patients and, when complicated, involves bone tissue. To explore host responses in bone tissue during Haemophilus influenzae-induced AOM modified by amoxicillin, a rat model and PCR techniques were used. The treatment eradicated the bacteria and induced changes in the expression profile of osteocalcin, a bone formation marker. The maximum levels of osteocalcin transcripts in the treatment group were delayed by about a week. The mRNA levels never reached the same high levels as in the untreated animal group, but the downregulation was slow and entailed higher osteocalcin mRNA levels for a longer time period in the treated animals. The expression of IL-6 and TNF-alpha, two cytokines associated with bone resorption, remained unaffected by the amoxicillin treatment, whereas the downregulation of IL-10, with suppressive effects on bone resorption, was slower than that during the natural course. By comparing the host responses on the molecular level in different tissues during treated and untreated AOM, new approaches to how to minimize the risks of severe AOM complications may evolve.
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PMID:Effects of amoxicillin on cytokine and osteocalcin expression in bone tissue during experimental acute otitis media. 1503 40