Auditory late potentials in normal-hearing adult subjects with Down's syndrome.

Objective: Several studies have demonstrated that adult subjects with Down's syndrome (DS) and hearing impairments show significantly delayed latencies in auditory late potentials (ALPs). The aim of this study was to investigate whether the differences were still present in ALPs in an adult DS population with normal hearing, taking into consideration sex, handedness, and head size.

Study Design: Prospective study.

Auditory brainstem responses (ABR) in normal hearing adult subjects with Down's syndrome.

Background: Auditory brainstem responses (ABRs) have been previously investigated in subjects with Down's syndrome (DS), but the published data are generally from children with hearing loss. The aim of this study was to evaluate the hearing pathway in normal hearing adult DS patients.

Methods: We used ABRs to analyze absolute and interpeak latencies in 19 adult DS patients aged 18-45 years whose pure tone audiometry (PTA) test results indicated thresholds within normal limits, and 19 normal controls.

Growth of melanocytes in human epidermal cell cultures.

Epidermal cell cultures were grown in keratinocyte-conditioned medium for use as burn wound grafts; the melanocyte composition of the grafts was studied under a variety of conditions. Melanocytes were identified by immunohistochemistry based on a monoclonal antibody (MEL-5) that has previously been shown to react specifically with melanocytes. During the first 7 days of growth in primary culture, the total number of melanocytes in the epidermal cultures decreased to 10% of the number present in normal skin.