Human papillomavirus infection of the esophagus. A clinicopathologic study with demonstration of papillomavirus antigen by the immunoperoxidase technique.

Papillomaviruses are known to be oncogenic in animals. In humans they are associated with benign squamous tumors (verruca, condylomata acuminata, and papillomas) in a variety of body sites. Human papillomavirus (HPV) infection of the esophagus, however, has not previously been documented.

Probability learning in pigeons (Columba livia) is not impaired by hyperstriatal lesions.

Three experiments investigated the effects of hyperstriatal lesions on spatial and visual probability learning in pigeons. The lesions did not affect choice accuracy although they did reduce positional responding on error trials in the visual task. The results gave support to a perseverative, as opposed to an attentional, interpretation of the lesion effects.

The role of keratinocyte differentiation in the expression of epitheliotropic viruses.

We have examined the growth of three epitheliotropic viruses in cultures of human epidermal keratinocytes: herpes simplex virus (HSV) type 1, adenovirus type 2 (Ad-2), and human papillomavirus (HPV) type 1. Differences were noted in the level of expression of each virus, and these differences may be related to a dependency or lack of dependency on keratinocyte differentiation for complete viral growth. Of the three viruses studied, HSV was the only one to replicate productively in all cells of the culture.

Serum, saliva, and sputum levels of metronidazole in acute exacerbations of chronic bronchitis.

We have evaluated the absorption and the penetration of metronidazole into the bronchial secretions and saliva in acute infective exacerbations of chronic bronchitis. Seventeen patients were given 400 mg orally three times daily for seven days and "steady state" levels were measured in serum, saliva, and sputum on the last day of treatment. Mean levels in the three biological fluids were not significantly different.

Possible role of the anaerobe in tonsillitis.

Anaerobic bacteria were isolated from all tonsils removed from children at routine tonsillectomy; 75.6% of specimens yielded moderate to heavy growth and 80% of tonsils contained more than one anaerobic species. This recovery rate fell to 56% after a 10-day course of metronidazole before tonsillectomy--in only 14.

The importance of patient selection for photochemotherapy in psoriasis.

Twenty-four patients with psoriasis were treated with orally administered 8-methoxypsoralen followed by exposure to high-intensity long-wavelength ultraviolet radiation (PUVA) at a psoriasis day care centre. Among the 20 with plaque type psoriasis the condition cleared in 13 (65%), after a mean of 20.7 treatment sessions, and improved but failed to clear in 4 (20%); the treatment failed in the other 3 (15%).

The carbon dioxide requirements of anaerobic bacteria.

Some clinically significant anaerobic bacteria were incubated in pure culture in anaerobic jars containing a range of atmospheric concentrations of CO2. Growth of Clostridium perfringens, C. sporogenes and C.