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Over a 15-yr time span, a 30-yr-old female chimpanzee (Pan troglodytes) exhibited recurrent upper respiratory disease that was suspected to be allergen induced. Until 1993, symptomatic therapy with several different antibiotics and antihistamines yielded variable results. In early 1993, the chimpanzee was consistently observed to be open-mouth breathing despite medication. Nasal polyposis was diagnosed using rigid endoscopy in September 1993, and the polyps were removed by loop excision. A fluorescent allergosorbent test was performed to differentiate hypersensitivity to specific regional allergens causing chronic inhalant allergic rhinitis. Oral immunotherapy was then instituted using standard human treatment for Sacramento Valley pollens. This combination of polyp removal and immunotherapy resulted in a marked reduction of clinical signs, and continuous oral immunotherapy has controlled these signs. Hyposensitization therapy will continue for at least 2-3 yr. The chimpanzee continues to breath normally following occasional antihistamine treatment.

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Respiratory syncytial virus (RSV) is the most important cause of acute viral bronchiolitis and pneumonia in infants and children. Management of RSV infection has changed dramatically over the past 5 to 7 years because of (1) the advent of widely available rapid tests for its specific identification and (2) use of the antiviral agent ribavirin (Virazole). Although RSV infection remains a life-threatening disease, particularly in certain high-risk groups, appropriate management and judicious use of ribavirin should help physicians reduce its morbidity and mortality.

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The structure of dynein isolated from several sources follows the pattern first observed with Tetrahymena 22S dynein, which has three globular heads attached by three flexible strands to a root-like base. Recent biochemical data indicate that there is one ATPase site on each dynein head and that all three heads interact with microtubules in an ATP-sensitive manner. Accordingly, images of dynein in situ can be interpreted in terms of a model for crossbridge action where the roots of the bouquet anchor the dynein to the A-tubule and all three heads reach out to interact with the B-tubule in an ATP-dependent reaction to produce a force for sliding.

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Benign osteoblastoma is a rare lesion of bone, usually confined to the long bones and the vertebrae. There have been 16 cases reported in the calvarium and only four in the frontal bone. We treated a patient with benign osteoblastoma of the frontal bone (supraorbital ridge and roof of orbit), and we review the literature. The histologic and radiologic characteristics are described and the treatment modalities are reviewed.

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Fifty eight patients receiving planned high-dose preoperative radiotherapy followed by en bloc oro-mandibular-cervical resection for oropharyngeal cancer were reviewed. These patients received continued close observation and care from both the Otolaryngology and Radiotherapy services. In light of the ongoing controversy of preoperative vs. postoperative radiotherapy, we present our data demonstrating the value of preoperative radiation. An overall tumor control rate of 66% was achieved, with an adjusted survival rate of 62%. This was not only for early lesions, but also in patients having advanced (T3, T4) tumor and/or nodal disease (N1-4). These figures are somewhat higher than expected from the literature. A review and discussion of the surgical complications are also presented.

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During glycerol-induced myxospore formation in Myxococcus xanthus, cellular neutral polysaccharide increases by approximately 200%, respiration decreases by 80%, and net phospholipid synthesis ceases.

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An extracellular coat from glycerol-induced myxospores of Myxococcus xanthus has been isolated and characterized. Coats were examined chemically and by using both transmission and scanning electron microscopy. On a dry weight basis, approximately 75% of the coat is polysaccharide composed entirely of galactosamine and glucose. The remainder of the coat is protein (14%), glycine (8%), and organic phosphorus (less than 1%). Coats remained morphologically intact despite boiling in 10 M urea, sodium lauryl sulfate plus beta-mercaptoethanol, or extraction with warm phenol. Coats also resisted digestion with a variety of proteolytic and polysaccharide degrading enzymes. Synthesis of myxospore coat begins approximately 1 h after the addition of glycerol to a culture. One portion of the coat is complete by 5 to 6 h but additional material consisting primarily of glucose is added after 8 h.

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The nature of the intramolecular hydrogen bond in the enol tautomer of 2,4-pentanedione has been investigated by high resolution proton and deuteron magnetic resonance spectroscopy. An unusually large deuterium isotope effect on the chemical shift of the bridge hydrogen has been observed. This unexpected result, together with the observation of a pronounced temperature dependence for both the proton and deuteron resonances, suggests that two states with different chemical shifts for the bridge hydrogen are involved in rapid equilibrium and that the anomalous deuterium isotope effect has its origin in the effect of deuterium substitution on the energy separation between these states. It is proposed that these states correspond to the symmetrical and asymmetrical structures of the intramolecular hydrogen bond.