Filter-culture technique using amoeba saline transport medium for the noninvasive diagnosis of Acanthamoeba keratitis.

Acanthamoeba, a common free-living amoeba, is increasingly incriminated as a cause of keratitis and corneal ulceration. Between March 1986 and July 1988, specimens from seven patients submitted by ophthalmologists to the City of Milwaukee Health Department's Bureau of Laboratories were culture positive for Acanthamoeba. All patients were contact lens wearers. The specimens were transported at ambient temperature in amoebasaline (5.0 mL) and filtered through 13 mm 0.22 microns cellulose filters. The filters were then plated in cocultivation with Escherichia coli on nonnutrient agar and had positive results for Acanthamoeba in two to five days. Contact lens cases were culture positive for Acanthamoeba in three instances. These results indicate that corneal scraping in amoeba saline transport medium can provide an effective way to diagnose Acanthamoeba keratitis when direct culture of such specimens is not possible.

The effectiveness of verbal versus activity groups in improving self-perceptions of interpersonal communication skills.

This study compares the efficacy of a verbal group with that of an activity group in an occupational therapy clinic during the treatment of interpersonal communication deficits at a psychiatric day treatment center. Outpatients were randomly assigned to the following groups: an experimental group, which received activity therapy (n = 7), an experimental group, which received verbal therapy (n = 6), and a control group, which was involved exclusively in the normal milieu therapy at the center (n = 6). The two experimental groups received one hour of treatment per week for eight weeks. The pretesting and posttesting of interpersonal communication skills were done with the Interpersonal Communication Inventory. The activity group used collages, problem-solving tasks, role-playing sessions, games, and drawing exercises. The verbal group used discussion exclusively. Both the activity and verbal groups were based on whether participants had the following: an adequate self-concept, the ability to be a good listener, the skill of expressing his or her thoughts and ideas clearly, the ability to cope with his or her emotions (particularly with angry feelings) and express them in a constructive way, and a willingness to disclose him- or herself to others freely and truthfully. A significantly higher level of interpersonal communication skills was attained by the activity group. Comparisons between both groups and the control group showed no significant differences.

Effects of timoptic on corneal reepithelialization.

The effects of topical 0.5% Timoptic on the reepithelialization of rabbit corneas were compared to the effects observed in rabbits receiving either vehicle, phosphate-buffered saline (PBS), PBS containing 0.5% timolol maleate, or no treatment. The rate of epithelial wound closure was slowed, and epithelial DNA content was less in both Timoptic- and vehicle-treated corneas. Light microscopy showed that the epithelium of animals treated with either Timoptic or vehicle processed fewer cellular layers in the wounded areas as well as considerable disruption of the epithelial layer. The rate of DNA synthesis and the cyclic adenosine monophosphate content of the epithelial cells from all treatment groups were statistically the same. The impaired wound closure observed during Timoptic and vehicle treatment was probably due to the sloughing of cells caused by the 0.01% benzalkonium chloride in the vehicle and not to impaired healing caused by the metabolic effects of timolol meleate.

Increased susceptibility to infection in experimental xerophthalmia.

Vitamin A-deficient rabbits were used to evaluate the role of secondary bacterial infection in the development of keratomalacia and to describe the resultant clinical and morphologic alterations. The conjunctival sacs of vitamin A-deficient rabbits at different stages of corneal involvement were inoculated with Pseudomonas aeruginosa topically. Approximately two weeks after inoculation, corneal ulceration with stromal melting developed in one of three eyes with severe punctate keratitis and in four of seven eyes with xerosis. Ulceration did not develop in any of the eight eyes with early epithelial graying or mild punctate keratitis. Inflammatory cells (primarily polymorphonuclear leukocytes) infiltrated the anterior corneal stroma of infected corneas. Liquefaction of collagen was observed in association with bacteria alone, as well as in association with polymorphonuclear leukocytes. No signs of infection were observed after conjunctival inoculation of Pseudomonas in the eyes of nine control rabbits.

Topical retinoic acid in the treatment of experimental xerophthalmia in the rabbit.

The purpose of this study was to evaluate the efficacy of topical retinoic acid (tretinoin) in the treatment of various stages of xerophthalmia caused by vitamin A deficiency. At the beginning of treatment, rabbits with similar disease in both eyes were given a normal diet and therapeutic doses (25,000 IU) of systemic vitamin A. One eye of each was treated with 0.1% retinoic acid in sesame oil one time per day. The other eye received sesame oil alone. Eyes with moderate disease (advanced keratinization and plaque formation) responded more quickly to topical retinoic acid (clear within three days) than did eyes treated with sesame oil (clear within seven days). No difference in time of response could be observed in corneas with milder or more severe disease (stromal infiltration and corneal vascularization).

Optimum imaging method for optical data processors.

Several two-lens systems are considered for imaging an input record with specified magnification and focal lengths. Under certain conditions the total length of each setup from input record to image can be minimized (absolute). Alternately, limiting values of minimum length configurations are determined in the neighborhood of the open endpoints of a range of operation.