Women Physicians and Promotion in Academic Medicine.

Background: In 2000, a landmark study showed that women who graduated from U.S. medical schools from 1979 through 1997 were less likely than their male counterparts to be promoted to upper faculty ranks in academic medical centers.

Early Onset Region and Cell Specific Alterations of Doublecortin Expression in the CNS of Animals with Sound Damage Induced Hearing Loss.

Sound damage induced hearing loss has been shown to elicit changes in auditory and non-auditory brain regions. A protein critical for neuronal migration and brain development, doublecortin (DCX), has been used as a marker of central nervous system (CNS) neuroplasticity. DCX is expressed in unipolar brush cells (UBCs) of the dorsal cochlear nucleus (DCN), cerebellar parafloccular lobe (PFL) and neuronal precursor cells in the sub-granular zone of the hippocampal dentate gyrus (DG).

Association of Skin and Cartilage Variables With Composite Graft Healing in a Rabbit Model.

Importance: Composite grafting in nasal reconstruction involves transplanting auricular chondrocutaneous grafts, but the optimal design of these grafts is unknown.

Objectives: To investigate the ideal ratio of skin to cartilage as well as study the importance of the perichondrial attachment for graft survival.

Design, Setting, And Participants: A New England white rabbit model was used in this study, performed at the Laboratory for Animal Research at University of Kansas Medical Center from January 25 to March 18, 2016.

Methionine Sulfoxide Reductase A Knockout Mice Show Progressive Hearing Loss and Sensitivity to Acoustic Trauma.

Methionine sulfoxide reductases (MsrA and MsrB) protect the biological activity of proteins from oxidative modifications to methionine residues and are important for protecting against the pathological effects of neurodegenerative diseases. In the current study, we characterized the auditory phenotype of the MsrA knockout mouse. Young MsrA knockout mice showed small high-frequency threshold elevations for auditory brainstem response and distortion product otoacoustic emission compared to those of wild-type mice, which progressively worsened in older MsrA knockout mice.

Post-tenure Review at U.S. Medical Schools.

Purpose: To assess post-tenure review policies at U.S. medical schools by examining how prevalent post-tenure review is, what models of post-tenure review are employed, and what outcomes result from post-tenure review processes.

Hearing, reactive metabolite formation, and oxidative stress in cochleae after a single acute overdose of acetaminophen: an in vivo study.

Context: Although the liver is the primary target organ in acetaminophen (APAP) toxicity, other organs are affected. Previous data suggested that chronic APAP abuse can be ototoxic and the mechanism involves APAP-induced oxidative stress and reactive metabolite (N-acetyl-p-benzoquinone imine, NAPQI)-induced endoplasmic reticulum stress. However, the effect of a single acute overdose on hearing has not been tested.

Hair cell counts in a rat model of sound damage: Effects of tissue preparation & identification of regions of hair cell loss.

Exposure to intense sound can damage or kill cochlear hair cells (HC). This loss of input typically manifests as noise induced hearing loss, but it can also be involved in the initiation of other auditory disorders such as tinnitus or hyperacusis. In this study we quantify changes in HC number following exposure to one of four sound damage paradigms.

Efficacy and toxicity of peritumoral delivery of nanoconjugated cisplatin in an in vivo murine model of head and neck squamous cell carcinoma.

Importance: Treatment of locally advanced head and neck squamous cell carcinoma (HNSCC) uses a multidisciplinary approach often limited by the toxicity and drug resistance of platinum agents.

Objectives: To test whether a nanocarrier-conjugated cisplatin boosting locoregional drug delivery improves tumor efficacy while decreasing systemic toxicity over systemic cisplatin in a murine model of locally advanced HNSCC.

Design: A randomized, controlled, in vivo study compared standard cisplatin with nanocarrier (hyaluronan [HA])-conjugated cisplatin (HA-cisplatin) each at 50% of the maximum tolerated doses in a murine model of locally advanced HNSCC (10 mice/arm, each injected with 1 × 106 MDA-1986 HNSCC cells, with phosphate-buffered saline and HA-only control arms).

Canalostomy as a surgical approach for cochlear gene therapy in the rat.

This article presents a unique approach for the delivery of gene therapy vectors into the cochlea of the laboratory rat. Mice and guinea pigs are established in vivo models for cochlear gene therapy each of which has distinct advantages and disadvantages. The rat has some of the molecular advantages of a mouse model combined with size advantages for surgical approaches.

Histochemical and fluorescent analyses of mitochondrial integrity in chick auditory neurons following deafferentation.

Background: Neurons rely exclusively on mitochondrial oxidative phosphorylation to meet cellular energy demands, and disruption of mitochondrial function often precipitates neuronal cell death. Auditory neurons in the chick brain stem (n. magnocellularis [NM]) receive glutamatergic innervation exclusively from ipsilateral eighth nerve afferents.

Effect of unilateral noise exposure on the tonotopic distribution of spontaneous activity in the cochlear nucleus and inferior colliculus in the cortically intact and decorticate rat.

Effects of unilateral noise exposure on spontaneous activity (SA) in the anteroventral and dorsal cochlear nuclei (AVCN and DCN) and the central nucleus of the inferior colliculus (ICc) were studied in cortically intact and decorticate rats. SA was measured 1 week following exposure using uptake of 14C-labeled 2-deoxyglucose (2DG) in quiet. Optical density (OD) measurements were obtained in low- and high-frequency (LF and HF) areas of each nucleus.

Role of cochlear integrity in cochlear nucleus glucose metabolism and neuron number after cochlea removal in aging broiler chickens.

In the chicken auditory system, cochlear nucleus (nucleus magnocellularis, NM) neurons receive their only excitatory input from the ipsilateral cochlea. Cochlea removal (CR) results in an immediate decrease in NM neuron electrical activity, followed by death of approximately 30% of NM neurons. Previous work showed a decrease in NM activity and subsequent loss of NM neurons in all chicks.

Breed-dependent susceptibility to acute sound exposure in young chickens.

Commercially available chickens fall into two categories: egg layers and broilers. Durham et al. (Hear.

Effect of cochlear integrity on cochlear nucleus neuron glucose metabolism in aged adult broiler chickens.

Abrupt removal of excitatory input is devastating to post-synaptic neurons in normally functioning sensory systems. In both mammalian and avian auditory systems, abrupt temporary or permanent experimental deafferentation stimulates a cascade of changes in central auditory structures that can result in neuron death. Effects of naturally occurring progressive deafferentation on central auditory structure and function have not been fully described.

Predicting severity of cochlear hair cell damage in adult chickens using DPOAE input-output functions.

Distortion product otoacoustic emissions (DPOAE) were recorded from the ear canal of aged broiler chickens which have been shown to present with age-related cochlear degeneration [Hear. Res. 166 (2002) 82].

Gentamicin pharmacokinetics in the chicken inner ear.

Avians have the unique ability to regenerate cochlear hair cells that are lost due to ototoxins or excessive noise. Many methodological techniques are available to damage the hair cells for subsequent scientific study. A recent method utilizes topical application of an ototoxic drug to the round window membrane.

Contributions of age, cochlear integrity, and auditory environment to avian cochlear nucleus metabolism.

Most commercially raised broiler chickens display progressive cochlear degeneration with age [Hear. Res. 166 (2002) 82].

Comparison and cross-validation of simple and multiple logistic regression models to predict USMLE step 1 performance.

Background: Early identification of students who may have difficulty with the United States Medical Licensing Examination-Step 1 examination is important for medical schools and students. Numerous models that predict Step 1 performance have been identified, but few of these models have been cross-validated.

Purpose: To cross-validate different prediction models of Step 1 performance.

Effects of age and cochlear damage on the metabolic activity of the avian cochlear nucleus.

Most aging commercially raised broiler chickens display a progressive loss of cochlear hair cells in a pattern similar to the cochlear degeneration found in aging humans: basal (high frequency) hair cells are affected first, followed by apical (low frequency) hair cells [Durham et al., Hear. Res.

Avian brainstem neurogenesis is stimulated during cochlear hair cell regeneration.

Unlike mammals, adult avians are able to regenerate cochlear sensory hair cells following injury. Brainstem auditory neurons in chicken nucleus magnocellularis (NM), which receive their sole excitatory afferent input from the cochlea, were examined for evidence of mitosis during ototoxin-induced loss and regeneration of cochlear hair cells. Using tritiated thymidine as a mitotic marker in tissue processed for autoradiography and counterstained with thionin, labeled NM neurons and glia were counted from chickens killed 16 days after gentamicin or saline injections.

Time course and quantification of changes in cochlear integrity observed in commercially raised broiler chickens.

Extensive cochlear hair cell damage and loss occurs in aged broiler chickens. We describe the time course and several characteristics of this decline in cochlear integrity in 19-, 30-, 38- and 66-week-old commercially raised broiler chickens. The 19-week-old group is normal and serves as a baseline for comparison.

Conductive hearing loss results in changes in cytochrome oxidase activity in gerbil central auditory system.

Conductive hearing loss (CHL) restricts auditory input to an intact peripheral auditory system. Effects of deprivation on the central auditory system (CAS) have been debated, although a number of studies support the hypothesis that CHL can cause modification of CAS structure and function. The present study was designed to test the hypothesis that unilateral CHL results in a decrease in cytochrome oxidase (CO) activity in CAS nuclei that receive major afferent input from the affected ear.

Breed differences in cochlear integrity in adult, commercially raised chickens.

Two types of chickens are commercially available. Broiler birds are bred to develop quickly for meat production, while egg layers are bred to attain a smaller adult size. Because we have observed breed differences in the response of central auditory neurons to cochlear ablation in adult birds [Edmonds et al.