Feasibility of Measuring the Behavioral and Electrophysiological Masking-Level Difference with Nonsense-Syllable Stimuli.

Background:  The masking-level difference (MLD) can be measured via voluntary behavioral responses (voluntary behavioral MLD [vMLD]) and/or via electrophysiological cortical auditory evoked potentials (CAEPs; electrophysiological MLD [eMLD]). It may be possible to enhance the ecologic validity of the MLD by using nonsense-syllable speech stimuli.

Purpose:  The aim of this study is to determine the feasibility of measuring both the vMLD and eMLD with speech stimuli.

The electrophysiological masking level difference: effects of age and mediation of hearing and cognition.

Objective: Evaluate the conceptual framework that age effects on the electrophysiological binaural masking level difference (MLD) are partially mediated by age-related hearing loss and/or global cognitive function via mediation analysis.

Design: Participants underwent a series of audiometric tests. The MLD was measured via cortical auditory evoked potentials using a speech stimulus (/ɑ/) in speech-weighted background noise.

Predicting hearing aid use in adults: the Beaver Dam Offspring Study.

Objective: The purpose of this study was to (i) develop a model that predicts hearing aid (HA) use and (ii) determine if model fit is improved by adding factors not typically collected in audiological evaluations.

Design: Two models were created and evaluated. The "clinical" model used factors typically collected during audiologic clinical evaluations.

Vestibular Function and Motion Sickness Susceptibility: Videonystagmographic Evidence From Oculomotor and Caloric Tests.

Purpose Motion sickness (MS) is a common condition that affects millions of individuals. Although the condition is common and can be debilitating, little research has focused on the vestibular function associated with susceptibility to MS. One causal theory of MS is an asymmetry of vestibular function within or between ears.

Electrophysiological Evidence for the Sources of the Masking Level Difference.

Purpose: The purpose of this review article is to review evidence from auditory evoked potential studies to describe the contributions of the auditory brainstem and cortex to the generation of the masking level difference (MLD).

Method: A literature review was performed, focusing on the auditory brainstem, middle, and late latency responses used in protocols similar to those used to generate the behavioral MLD.

Results: Temporal coding of the signals necessary for generating the MLD occurs in the auditory periphery and brainstem.

Hyperinsulinemia/diabetes, hearing, and aging in the University of Wisconsin calorie restriction monkeys.

The purpose of this study was to determine the effects of hyperinsulinemia/Type 2 diabetes mellitus (HI-T2DM) on hearing impairment using rhesus monkeys to obtain control over diet and lifestyle factors that confound human studies. The study is a retrospective evaluation of rhesus monkeys from the Wisconsin National Primate Research Center (WNPRC) study on caloric restriction and aging. The research questions were the following: 1.

Effects of motion sickness severity on the vestibular-evoked myogenic potentials.

Background: Motion sickness is a common debilitating condition associated with both actual and perceived motion. Despite the commonality, little is known about the underlying physiological mechanisms. One theory proposes that motion sickness arises from a mismatch between reality and past experience in vertical motions.

Frequency dependence of binaural interaction in the auditory brainstem and middle latency responses.

Purpose: The primary purpose of this investigation was to determine the relative frequency representation of binaural function in the brainstem and cortex of adults. The secondary purpose was to compare adult responses to previously reported infant responses.

Methods: Simultaneous auditory brainstem responses and auditory middle responses were recorded monaurally and binaurally in 20 young women.

Relationships among standard and wideband measures of middle ear function and distortion product otoacoustic emissions.

Background: The overall goal of the current study was to examine the relationships among uncompensated admittance (Ya) at ambient pressure extracted from tympanograms, energy reflectance (ER) measures at ambient pressure from wideband acoustic transfer functions (WATF), and distortion product otoacoustic emissions (DPOAEs). If WATF measures of Ya are comparable to tympanometric measures of Ya at ambient pressure, it would be further evidence that the two systems provide comparable information at ambient pressure. Such a relationship could be used as a cross-check or validation for WATF measures and support the use of WATFs in lieu of tympanograms in some applications.

Clinical breakpoints for voriconazole and Candida spp. revisited: review of microbiologic, molecular, pharmacodynamic, and clinical data as they pertain to the development of species-specific interpretive criteria.

We reassessed the Clinical and Laboratory Standards Institute (CLSI) clinical breakpoints (CBPs) for voriconazole. We examined i) the essential (EA: ±2 dilutions) and categorical agreement between 24-h CLSI and EUCAST methods for voriconazole testing of Candida, ii) wild-type (WT) MICs and epidemiologic cutoff values (ECVs) for voriconazole by both CLSI and EUCAST methods, and iii) correlation of MICs with outcomes from previously published data using CLSI methods. We applied these findings to propose new 24-h species-specific CLSI CBPs.

Procalcitonin for triage of patients with respiratory tract symptoms: a case study in the trial design process for approval of a new diagnostic test for lower respiratory tract infections.

Symptoms of cough, fever, chest pain, and shortness of breath are common reasons that patients seek medical care, and they can be due to a variety of medical conditions, including lower respiratory tract infection (LRTI). Only a small proportion of these patients will actually have a bacterial etiology, but many will receive antibiotic treatment because physicians cannot readily determine the etiology at the time of presentation. Current diagnostic methodologies are not sensitive or specific enough to reliably distinguish bacterial from viral or noninfectious etiologies.

Auditory function in rhesus monkeys: effects of aging and caloric restriction in the Wisconsin monkeys five years later.

Caloric restriction (CR) slows aging in many species and protects some animals from age-related hearing loss (ARHL), but the effect on humans is not yet known. Because rhesus monkeys are long-lived primates that are phylogenically closer to humans than other research animals are, they provide a better model for studying the effects of CR in aging and ARHL. Subjects were from the pool of 55 rhesus monkeys aged 15-28 years who had been in the Wisconsin study on CR and aging for 8-13.

Sudden bilateral sensorineural hearing loss following speedballing.

Background: Hearing loss is an infrequently-reported consequence of recreational drug abuse. Although there are sporadic reports of hearing loss from heroin and cocaine ingested separately, there are no reports of hearing loss resulting from the combination of both drugs ingested simultaneously in the form of speedballing.

Purpose: The purpose of this report is to document a case of bilateral sensorineural hearing loss associated with an episode of speedballing.

Tympanometry in rhesus monkeys: effects of aging and caloric restriction.

Caloric restriction is the only known method of increasing lifespan in laboratory animals. The present study was conducted as part of a larger investigation into the effect of caloric restriction on longevity of rhesus monkeys as a model for human aging. This study focused on the effects of caloric restriction and aging on measures of middle-ear function measured with tympanometry.

The reciprocal effects of eating disorders and the postpartum period: a review of the literature and recommendations for clinical care.

This paper examines the areas of psychological and physiological concern when working with patients who have eating disorders as they move through the postpartum period. These concerns include infant feeding, maternal-child bonding, and postpartum adjustment. The combination of psychological stressors of new motherhood and body image concerns intensified by the residual bodily changes of pregnancy may predispose women to have an exacerbation in eating disordered symptoms as well as the development of postpartum mood disorders.

Amplitude-modulated auditory steady-state responses in younger and older listeners.

The primary purpose of this investigation was to determine whether temporal coding in the auditory system was the same for younger and older listeners. Temporal coding was assessed by amplitude-modulated auditory steady-state responses (AM ASSRs) as a physiologic measure of phase-locking capability. The secondary purpose of this study was to determine whether AM ASSRs were related to behavioral speech understanding ability.

Assessment of auditory function in rhesus monkeys (Macaca mulatta): effects of age and calorie restriction.

Age-related alterations in auditory function were evaluated in adult male rhesus monkeys (Macaca mulatta) involved in a long-term study evaluating the effects of caloric restriction (CR) on aging. We assessed 26 monkeys in a control group fed a low fat, high fiber diet at approximately ad libitum levels and 24 monkeys in a CR group that were fed the same diet reduced in amount by 30% compared to age- and weight-matched controls. The following measures of auditory function were obtained while monkeys were maintained under anesthesia: (1) distortion product otoacoustic emissions (DPOAEs); (2) auditory brainstem responses (ABRs); and (3) middle latency responses (MLRs).

Relationship between fluoroquinolone area under the curve: minimum inhibitory concentration ratio and the probability of eradication of the infecting pathogen, in patients with nosocomial pneumonia.

Our objective was to prospectively determine the factors influencing the probability of a good microbiological or clinical outcome in patients with nosocomial pneumonia treated with a fluoroquinolone. Levofloxacin was administered as an infusion of 500 mg/h for 1.5 h (total dose, 750 mg).

Levofloxacin compared with imipenem/cilastatin followed by ciprofloxacin in adult patients with nosocomial pneumonia: a multicenter, prospective, randomized, open-label study.

Background: Therapy of nosocomial pneumonia is usually empiric and includes > or = 1 broad-spectrum antimicrobial agent. When considering the use of fluoroquinolones in these difficult-to-treat infections--in which drug delivery to the site of infection may be impaired or organisms with higher minimum inhibitory concentrations may be present--an agent should be chosen whose pharmacodynamics ensure maximal drug exposure. Use of the 750-mg dose of levofloxacin should enhance therapeutic benefit in patients with nosocomial pneumonia.

Once-daily, high-dose levofloxacin versus ticarcillin-clavulanate alone or followed by amoxicillin-clavulanate for complicated skin and skin-structure infections: a randomized, open-label trial.

This study tested whether levofloxacin, at a new high dose of 750 mg, was effective for the treatment of complicated skin and skin-structure infections (SSSIs). Patients with complicated SSSIs (n=399) were randomly assigned in a ratio of 1:1 to 2 treatment arms: levofloxacin (750 mg given once per day intravenously [iv], orally, or iv/orally) or ticarcillin-clavulanate (TC; 3.1 g given iv every 4-6 hours) followed, at the investigator's discretion, by amoxicillin-clavulanate (AC; 875 mg given orally every 12 hours).

Effects of caloric restriction and aging on the auditory function of rhesus monkeys (Macaca mulatta): The University of Wisconsin Study.

The present study is part of a larger project that investigates the effect of caloric restriction on longevity in the rhesus monkey. The purpose of the present study was to document presbycusis and the effect of caloric restriction on presbycusis in monkeys. The control group had 35 monkeys allowed to eat freely and the caloric-restricted group (CR) had 33 monkeys with a 30% reduction in caloric intake.

Diagnostic implications of stimulus polarity effects on the auditory brainstem response.

The purpose of this study was to determine whether clicks presented in rarefaction or condensation modes produce more accurate diagnostic information. Subjects were 20 consecutive patients who were seen at the Mayo Clinic for unilateral acoustic neuromas. The nontumor ear served as a control to minimize intersubject variability in the latencies.