Giant Cutaneous Horn Arising in an Epidermal Nevus

Cutaneous horns, which rarely occur in children, can overlie a large array of pathologic lesions that range from benign to malignant. When a cutaneous horn is encountered, it is not the horn itself that is of relevance, it is the nature of the underlying disease that dictates overall prognosis and management. In this report we present a case of a cutaneous horn arising within a linear verrucous epidermal nevus and briefly review cutaneous horns, with an emphasis on their clinical implications and differential diagnosis.     

Prevalence of age-related hearing loss in Europe: a review

Populations are becoming progressively older thus presenting symptoms of diminished organ function due to degenerative processes. These may be physiological or caused by additional factors damaging the organ. Presbyacusis refers to the physiological age-related changes of the peripheral and central auditory system leading to hearing impairment and difficulty understanding spoken language. In contrast to epidemiological data of other continents, the prevalence of age-related hearing loss (ARHL) in Europe is not well defined, due in part to the use of different classification systems. We performed a systematic literature review with the aim of gaining a picture of the prevalence of ARHL in Europe. The review included only population and epidemiological studies in English since 1970 with samples in European countries with subjects aged 60 years and above. Nineteen studies met our selection criteria and additional five studies reported self-reported hearing impairment. When these data were crudely averaged and interpolated, roughly 30% of men and 20% of women in Europe were found to have a hearing loss of 30 dB HL or more by age 70 years, and 55% of men and 45% of women by age 80 years. Apparent problems in comparing the available data were the heterogeneity of measures and cut-offs for grades of hearing impairment. Our systematic review of epidemiological data revealed more information gaps than information that would allow gaining a meaningful picture of prevalence of ARHL. The need for standardized procedures when collecting and reporting epidemiological data on hearing loss has become evident. Development of hearing loss over time in conjunction with the increase in life expectancy is a major factor determining strategies of detection and correction of ARHL. Thus, we recommend using the WHO classification of hearing loss strictly and including standard audiometric measures in population-based health surveys.     

Specific immunoadsorption of pathogenic autoantibodies in pemphigus requires the entire ectodomains of desmogleins

Pemphigus foliaceus (PF) and pemphigus vulgaris (PV) are life‐threatening autoimmune blistering skin diseases. They are characterized by circulating autoantibodies which bind to the ectodomains of desmoglein (Dsg) 1 and Dsg3. These antibodies induce acantholysis in skin and mucous membranes. In severe cases of pemphigus, immunoadsorption is applied to remove total IgG from patient plasma using protein A or other ligands. To develop a specific adsorber for anti‐Dsg antibodies, epitope mapping studies of Dsg1 and Dsg3 ectodomains were conducted. Dsg variants were expressed on the surface of HEK‐293 cells and analysed for reactivity with pemphigus and control sera by indirect immunofluorescence technique. For Dsg1, a construct consisting of domain 1 directly fused to domain 5, seemed to be suitable for specific immunoadsorption of anti‐Dsg1 antibodies. The recognized epitopes were mainly conformation‐dependent. However, adsorption of pemphigus foliaceus IgG using this protein coupled to a Sepharose matrix did not completely remove pathogenicity from the sera, as proven by a keratinocyte dissociation assay. In contrast, full‐length Dsg1 and Dsg3 ectodomains were able to specifically adsorb anti‐Dsg antibodies and to efficiently eliminate pathogenicity. Therefore, the complete and correctly folded ectodomains of both desmogleins are required for therapeutic immunoadsorption.     

Acute acoustic trauma. A retrospective study of influencing factors and different therapies in 268 patients

The files of 268 patients with acute acoustic trauma acquired during military service were analysed in a retrospective study. The following factors were examined: age, profession, degree of hearing loss, audiometric contour, and drug treatment. No influence of age or profession on recovery of hearing loss could be detected. The absolute hearing gain, defined as the difference between the hearing loss at onset and, on average, 7 days later, was dependent on the degree of initial hearing loss. The relative hearing gain, defined as absolute hearing gain divided by initial hearing loss, was independent of the degree of initial injury. The audiometric contour after the acoustic trauma had no prognostic relevance. Nine different types of drug treatment were compared in a subgroup of patients (n=199), in all of whom treatment was started within 2 days of the acoustic trauma. There were no significant differences in relative hearing gain between the nine types of treatment. Patients receiving early treatment had significantly better hearing one week after the acoustic trauma, as compared with the group of patients (n=69) not receiving treatment during the first 7 days. However, it was not possible to determine retrospectively whether this difference was due to treatment effects, or whether it was due to the exclusion of spontaneous remissions among those who were neither examined nor treated within the first 7 days.     

Suppression of the 2f1-f2 otoacoustic emission in humans.

Suppression of the 2f1-f2 distortion-product otoacoustic emission (DPOAE), stimulated with primaries, f1 and f2, in the frequency regions of 1, 2, and 4 kHz was measured in one ear of 14 human subjects with normal hearing. Suppression rate functions were generated with a suppressor at either 1, 2, or 4 kHz increasing in level from 30 to 76 dB SPL for the corresponding f1 and f2 combinations. Stimulus levels for DPOAEs were L1 = 70 dB SPL and L2 adjusted to produce the highest amplitude DPOAE for each ear (range, 0 to 6 dB below L1). Results indicated that DPOAEs were reduced 3 dB in amplitude for a mean suppressor level of 61 dB SPL. Maximum amplitude reduction occurred at a mean suppressor level of 69 dB SPL. These levels varied little for the three stimulus frequency regions. Mean slopes of the rate functions decreased as stimulus frequency region increased. Suppression tuning curves (STCs) were generated in the same three frequency regions and with L1 at either 70 or 55 dB SPL and L2 adjusted individually for each ear. The tips of the STCs were at frequencies associated with f1 and f2. The tip regions of the STCs for the 4-kHz stimulus condition were more complex in that they contained more multiple minima than did those for the 1- and 2-kHz regions. Results confirm that optimal suppression of the 2f1-f2 DPOAE occurs for frequencies in the vicinity of f1 and f2 rather than at 2f1-f2.     

Transiently evoked otoacoustic emissions in patients with Menière's disease.

Transiently evoked otoacoustic emissions (TEOAEs) were stimulated using clicks or 1-kHz tone bursts in both ears of 31 patients with unilateral Meniere's disease. Using click stimuli, responses were present in 29/31 of the non-Meniere's ears and in 26/31 of the Meniere's ears. Stimulation using 1-kHz tone bursts produced responses in 30/31 of the non-Meniere's ears and in 28/31 of the Meniere's ears. Audiometric configuration strongly influenced the presence of TEOAEs in the affected ears. In all but 2 ears with average hearing sensitivity (0.5, 1, 2 kHz) poorer than 25 dB HL, responses were present only when accompanied by at least one pure-tone threshold better than 30 dB HL from 0.75 to 2 kHz. In the opposite ears, all of which had essentially normal hearing, responses were approximately 5 dB lower in level and contained fewer spectral peaks in comparison with results obtained from a normative database. Neither age nor pure-tone results could account for these differences. Thus, TEOAEs obtained from patients with Meniere's disease manifest features that may be considered as atypical either in comparison to results from ears with normal hearing or from ears with relatively flat sensorineural hearing losses due to other etiologies.     

Acoustic distortion products in rabbit ear canal. I. Basic features and physiological vulnerability

In contrast to evoked otoacoustic emissions, acoustic distortion products (DPs) recorded from the ear canal are present at predictable frequencies with respect to their primary tones, f1 and f2. Such specificity may provide detailed frequency-place information concerning the functional state of limited regions of the organ of Corti following experimental intervention. However, to date, it is not clear whether emitted DPs solely reflect activity at the basilar-membrane regions of primary tones or if the remote DP site makes a significant contribution to the emitted signal measured in the ear canal. We have investigated a number of the general features of acoustic-DP generation in the rabbit so that, in later experiments, the contributions of specific basilar-membrane regions involved in generating these DPs can be identified using techniques designed to manipulate their normal properties. The first report describes the outcome of systematic manipulations of a number of stimulus conditions and alterations to the physiological state of the cochlea by exposure to fatiguing sound or anoxia. Experimental findings for the 2f1-f2 DP showed that, in general, the relations of the levels and frequency of the primary tones to DP magnitude were consistent with previously published data from other mammalian species. Additional observations for other odd-order intermodulation DPs at the 3f1-2f2 and 2f2-f1 frequencies suggested that the basic attributes of the acoustic DPs were similarly affected by systematic manipulation of the basic parameters of the primary tones and the general metabolic state of the cochlea. General anesthesia, however, did not affect DP amplitude. A companion paper describes the results of a series of subsequent experiments using response-suppression, interfering-tone, and temporary threshold shift techniques which address more directly the issue of which basilar-membrane sites contribute to the generation of different acoustic DPs.