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Study Objective: Vaginal packing is traditionally placed after pelvic floor reconstructive surgery (PFRS) to prevent hematoma formation. We seek to determine if there is a difference in postoperative pain scores after PFRS if vaginal packing is soaked with estrogen cream, bupivacaine, or saline. The primary outcome was pain as measured by a visual analog scale at 2 hours, 6 hours, and 1 day postoperatively. Secondary outcomes include changes in hemoglobin, urinary retention and length of stay (LOS) in hospital., Design: Prospective cohort study., Setting: Tertiary care academic teaching hospital. All PFRS is performed by fellowship-trained urogynecologists., Participants: Consenting patients undergoing PFRS., Interventions: At the completion of surgery, gauze packing soaked with either estrogen cream, 0.25% bupivacaine with 1% epinephrine, or normal saline was placed inside the vagina and removed on postoperative day 1., Measurements and Main Results: We included 210 patients (74 estrogen, 66 bupivacaine, 70 saline). There was no significant difference in mean postoperative pain scores between the groups (estrogen, bupivacaine, saline-soaked vaginal packs respectively) at 2 hours (2.66 ± 2.25, 2.30 ± 2.17, 2.24 ± 2.07; p = .4656), 6 hours (2.99 ± 2.38, 2.52 ± 2.30, 2.36 ± 2.01; p = .2181) or on postoperative day 1 (1.89 ± 2.01 vs 2.08 ± 2.15 vs 2.44 ± 2.19; p = .2832) as measured by visual analog scale scores (0-10). There was no difference in the secondary outcomes of change in pre/postoperative hemoglobin (21.8 ± 10.73g/L, 20.09 ± 11.55 g/L, 21.7 ± 9.62g/L, p = .68), urinary retention (37%, 45% and 48%, p = .45), LOS (1.05 ± 0.46 days, 1.02 ± 0.12, 1.03 ± 0.24, p = .97) or in-hospital opioid usage during admission (represented in morphine milligram equivalents [median (IQR1, IQR3)], Kruskal-Wallis test): 11.25 mg (0, 33), 7.5 mg (0, 22.5) and 15 mg (0, 33.88) p = .41., Conclusion: There was no difference found between soaking vaginal packing with estrogen cream, bupivacaine, or saline after PFRS with respect to postoperative pain scores, LOS, in-hospital opioid usage, or urinary retention. Saline-soaked packing is an equivalent alternative to estrogen or bupivacaine vaginal packing., (Copyright © 2024 AAGL. Published by Elsevier Inc. All rights reserved.)

Background: Stress urinary incontinence affects approximately 40% of adult females and is often treated surgically. Minimally invasive vaginal laser therapy to treat stress urinary incontinence has become widely available, but the efficacy of this novel therapy is unclear., Objective: This study aimed to determine the efficacy of erbium-doped yttrium aluminum garnet laser as a therapy for stress urinary incontinence., Study Design: This was a double-blind randomized sham-controlled trial with 6-week and 6-month follow-ups at a single tertiary hospital setting with 144 adult female patients with symptomatic stress urinary incontinence. Each participant received 2 vaginal laser therapies 6 weeks apart, with patients randomized to either laser or sham. The primary outcome was patients' subjective reporting of no urinary incontinence at 6 months after treatment on question 3 of the International Consultation on Incontinence Questionnaire-Short Form. The secondary outcomes included objective measures of urine loss with 24-hour pad tests, 3 incontinence symptom questionnaires (Urogenital Distress Inventory-6, Incontinence Impact Questionnaire-7, and International Consultation on Incontinence Questionnaire-Short Form), 1 quality-of-life questionnaire (King's Health Questionnaire), and 1 sexual function questionnaire (Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire)., Results: Of 263 individuals approached, 76 of 144 individuals were randomized to the laser treatment group, and 68 of 144 individuals were randomized to the sham treatment group. There was no difference in the reported cure rate and the primary outcome at 6 months after treatment between the groups (laser treatment group: 0.0136; 95% confidence interval, 0.0006-0.0811; sham treatment group: 0.0000; 95% confidence interval, 0.0000-0.0666). Apart from a statistically significant difference noted at 6 weeks after treatment in 1 of 3 incontinence questionnaires and 3 of 9 domains of the quality-of-life questionnaire, there were no other significant differences in our subjective or objective measures between the 2 groups at 6 weeks and 6 months after treatment., Conclusion: Er: YAG laser was no more effective than sham for curing or improving female stress urinary incontinence at 6 months., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objectives: The Omicron variant of the SARS-CoV-2 virus is described as more contagious than previous variants. We sought to assess risk to health care workers (HCWs) caring for patients with COVID-19 in surgical/obstetrical settings, and the perception of risk among this group., Methods: From January to April 2022, reverse transcription polymerase chain reaction was used to detect the presence of SARS-CoV-2 viral ribonucleic acid in patient, environmental (floor, equipment, passive air) samples, and HCWs' masks (inside surface) during urgent surgery or obstetrical delivery for patients with SARS-CoV-2 infection. The primary outcome was the proportion of HCWs' masks testing positive. Results were compared with our previous cross-sectional study involving obstetrical/surgical patients with earlier variants (2020-2021). HCWs completed a risk perception electronic questionnaire., Results: Eleven patients were included: 3 vaginal births and 8 surgeries. In total, 5/108 samples (5%) tested positive (SARS-CoV-2 Omicron) viral ribonucleic acid: 2/5 endotracheal tubes, 1/22 floor samples, 1/4 patient masks, and 1 nasal probe. No samples from the HCWs' masks (0/35), surgical equipment (0/10), and air (0/11) tested positive. No significant differences were found between the Omicron and 2020/21 patient groups' positivity rates (Mann-Whitney U test, P = 0.838) or the level of viral load from the nasopharyngeal swabs (P = 0.405). Nurses had a higher risk perception than physicians (P = 0.038)., Conclusion: No significant difference in contamination rates was found between SARS-CoV-2 Omicron BA.1 and previous variants in surgical/obstetrical settings. This is reassuring as no HCW mask was positive and no HCW tested positive for COVID-19 post-exposure., (Copyright © 2023 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.)

Impulsive behavior and impulsivity are heritable phenotypes that are strongly associated with risk for substance use disorders. Identifying the neurogenetic mechanisms that influence impulsivity may also reveal novel biological insights into addiction vulnerability. Our past studies using the BXD and Collaborative Cross (CC) recombinant inbred mouse panels have revealed that behavioral indicators of impulsivity measured in a reversal-learning task are heritable and are genetically correlated with aspects of intravenous cocaine self-administration. Genome-wide linkage studies in the BXD panel revealed a quantitative trait locus (QTL) on chromosome 10, but we expect to identify additional QTL by testing in a population with more genetic diversity. To this end, we turned to Diversity Outbred (DO) mice; 392 DO mice (156 males, 236 females) were phenotyped using the same reversal learning test utilized previously. Our primary indicator of impulsive responding, a measure that isolates the relative difficulty mice have with reaching performance criteria under reversal conditions, revealed a genome-wide significant QTL on chromosome 7 (max LOD score = 8.73, genome-wide corrected p<0.05). A measure of premature responding akin to that implemented in the 5-choice serial reaction time task yielded a suggestive QTL on chromosome 17 (max LOD score = 9.14, genome-wide corrected <0.1). Candidate genes were prioritized ( 2900076A07Rik, Wdr73 and Zscan2) based upon expression QTL data we collected in DO and CC mice and analyses using publicly available gene expression and phenotype databases. These findings may advance understanding of the genetics that drive impulsive behavior and enhance risk for substance use disorders., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Background: The exposure risks to front-line health care workers caring for patients with SARS-CoV-2 infection undergoing surgery or obstetric delivery are unclear, and an understanding of sample types that may harbour virus is important for evaluating risk. We sought to determine whether SARS-CoV-2 viral RNA from patients with SARS-CoV-2 infection undergoing surgery or obstetric delivery was present in the peritoneal cavity of male and female patients, in the female reproductive tract, in the environment of the surgery or delivery suite (surgical instruments or equipment used, air or floors), and inside the masks of the attending health care workers., Methods: We conducted a cross-sectional study from November 2020 to May 2021 at 2 tertiary academic Toronto hospitals, during urgent surgeries or obstetric deliveries for patients with SARS-CoV-2 infection. The presence of SARS-CoV-2 viral RNA in patient, environmental and air samples was identified by real-time reverse transcription polymerase chain reaction (RT-PCR). Air samples were collected using both active and passive sampling techniques. The primary outcome was the proportion of health care workers' masks positive for SARS-CoV-2 RNA. We included adult patients with positive RT-PCR nasal swab undergoing obstetric delivery or urgent surgery (from across all surgical specialties)., Results: A total of 32 patients (age 20-88 yr) were included. Nine patients had obstetric deliveries (6 cesarean deliveries), and 23 patients (14 male) required urgent surgery from the orthopedic or trauma, general surgery, burn, plastic surgery, cardiac surgery, neurosurgery, vascular surgery, gastroenterology and gynecologic oncology divisions. SARS-CoV-2 RNA was detected in 20 of 332 (6%) patient and environmental samples collected: 4 of 24 (17%) patient samples, 5 of 60 (8%) floor samples, 1 of 54 (2%) air samples, 10 of 23 (43%) surgical instrument or equipment samples, 0 of 24 cautery filter samples and 0 of 143 (95% confidence interval 0-0.026) inner surface of mask samples., Interpretation: During the study period of November 2020 to May 2021, we found evidence of SARS-CoV-2 RNA in a small but important number of samples obtained in the surgical and obstetric operative environment. The finding of no detectable virus inside the masks worn by the health care teams would suggest a low risk of infection for health care workers using appropriate personal protective equipment., Competing Interests: Competing interests: Robert Kozak reports a grant from the Ontario Together Fund. Grace Liu reports a speaker payment from Hologic and reports an unpaid position as a board member for the American Association of Gynecologic Laparoscopists, 2019–2021. No other competing interests were declared., (© 2022 CMA Impact Inc. or its licensors.)

Circadian variability is driven by genetics and Diversity Outbred (DO) mice is a powerful tool for examining the genetics of complex traits because their high genetic and phenotypic diversity compared to conventional mouse crosses. The DO population combines the genetic diversity of eight founder strains including five common inbred and three wild-derived strains. In DO mice and their founders, we established a high-throughput system to measure cellular rhythms using in vitro preparations of skin fibroblasts. Among the founders, we observed strong heritability for rhythm period, robustness, phase and amplitude. We also found significant sex and strain differences for these rhythms. Extreme differences in period for molecular and behavioral rhythms were found between the inbred A/J strain and the wild-derived CAST/EiJ strain, where A/J had the longest period and CAST/EiJ had the shortest. In addition, we measured cellular rhythms in 329 DO mice, which displayed far greater phenotypic variability than the founders-80% of founders compared to only 25% of DO mice had periods of ~ 24 h. Collectively, our findings demonstrate that genetic diversity contributes to phenotypic variability in circadian rhythms, and high-throughput characterization of fibroblast rhythms in DO mice is a tractable system for examining the genetics of circadian traits.

Study Objective: To assess the effect of a surgical teaching video on junior resident knowledge and performance of a laparoscopic salpingo-oophorectomy (LSO)., Design: Randomized controlled trial., Setting: Urban tertiary care academic obstetrics and gynecology department., Patients: First- and second-year gynecology residents., Interventions: Access to an education video on LSO for 1 week before performing this surgery in the operating room., Measurements and Main Results: Twenty-four junior residents were recruited and randomized to either the educational video group or traditional residency training group. All participants completed a demographic survey and knowledge questionnaire before performing an LSO, which was video-recorded. Video recordings of surgical performance were analyzed using the Objective Structured Assessment of Technical Skills (OSATS; 20 points) and an LSO-specific tool (30 points). Participants completed a self-assessment questionnaire before completing the procedure. The primary outcome measure was the difference in OSATS scores. The secondary outcomes were the knowledge questionnaire scores and self-assessed confidence scores. There were no significant differences between demographic variables of the 2 groups. The primary outcome revealed no significant differences in mean (standard deviation) OSATS scores (10.64 [2.05] vs 11.55 [1.85], p = .3) or LSO-specific tool scores (16.45 [2.68] vs 17.85 [2.63], p = .24). However, there was a significant difference in mean knowledge scores between the video and the traditional training (8.42 [0.79] vs 7.11 [1.36], p = .01) groups. In addition, residents in the video group had more confidence in their knowledge of pelvic anatomy (3.83 [0.39] vs 3.00 [1.00] out of 5.00, p = .04)., Conclusion: For junior learners, the use of an LSO video improved knowledge and confidence in anatomy but did not translate to improved surgical performance in the operating room. Surgical videos are a useful adjunct and complement hands-on technical teaching., (Copyright © 2020 AAGL. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate whether the use of a Mayo Scissor as a suburethral spacer compared with a Babcock clamp holding a loop of tape under the urethra results in different rates of abnormal bladder outcomes 12 months after retropubic midurethral sling surgery., Methods: The MUST (Mid-Urethral Sling Tensioning) trial was a block-randomized, double-blind, multicenter clinical trial that allocated women to have their retropubic midurethral slings tensioned by Scissor or Babcock technique. The primary outcome (abnormal bladder) was a composite of persistent stress urinary incontinence (SUI), overactive bladder, and urinary retention. Secondary outcomes included outcomes of the composite, postoperative catheterization, incontinence-related questionnaires, repeat incontinence treatment, and uroflowmetry. Sample size of 159 in each arm (N=318) was planned for a superiority trial, hypothesizing a 10% difference in primary outcome., Results: From September 2015 to December 2017, 506 women were screened and 318 were randomized. Baseline characteristics were similar in each arm. At 12 months, 253 (79.6%) women provided information on primary outcome: 40 of 128 (31.3%) patients with midurethral slings tensioned by Scissor experienced abnormal bladder, compared with 23 of 125 (18.4%) of those with midurethral slings tensioned by Babcock (P=.018, relative difference 12.9%). Secondary analyses favored Babcock for median duration of catheterization and the proportions of women experiencing urinary retention requiring sling lysis. Uroflowmetry parameters suggest the Scissor technique is more restrictive. Rates of mesh erosion were lower for the Scissor arm. No differences occurred in proportions of women experiencing patient reported persistent SUI after surgery., Conclusion: Abnormal bladder outcomes were 12.9% less frequent for women with midurethral slings tensioned by Babcock. Both techniques provided a comparable patient reported cure for SUI at 12 months. Women with midurethral slings tensioned by Scissors experienced more intervention for obstruction, whereas those with midurethral slings tensioned by Babcock experienced higher rates of mesh erosion. This information about how the postoperative courses differ allows surgeons to better counsel patients preoperatively or tailor their choice of technique., Clinical Trial Registration: ClinicalTrials.gov, NCT02480231., Funding Source: Boston Scientific.

Rationale: Few effective treatments exist for cocaine use disorders due to gaps in knowledge about its complex etiology. Genetically defined animal models provide a useful tool for advancing our understanding of the biological and genetic underpinnings of addiction-related behavior and evaluating potential treatments. However, many attempts at developing mouse models of behavioral disorders were based on overly simplified single gene perturbations, often leading to inconsistent and misleading results in pre-clinical pharmacology studies. A genetically complex mouse model may better reflect disease-related behaviors., Objectives: Screening defined, yet genetically complex, intercrosses of the Collaborative Cross (CC) mice revealed two lines, RIX04/17 and RIX41/51, with extreme high and low behavioral responses to cocaine. We characterized these lines as well as their CC parents, CC004/TauUnc and CC041/TauUnc, to evaluate their utility as novel model systems for studying the biological and genetic mechanisms underlying behavioral responses to cocaine., Methods: Behavioral responses to acute (initial locomotor sensitivity) and repeated (behavioral sensitization, conditioned place preference, intravenous self-administration) exposures to cocaine were assessed. We also examined the monoaminergic system (striatal tissue content and in vivo fast scan cyclic voltammetry), HPA axis reactivity, and circadian rhythms as potential mechanisms for the divergent phenotypic behaviors observed in the two strains, as these systems have a previously known role in mediating addiction-related behaviors., Results: RIX04/17 and 41/51 show strikingly divergent initial locomotor sensitivity to cocaine with RIX04/17 exhibiting very high and RIX41/51 almost no response. The lines also differ in the emergence of behavioral sensitization with RIX41/51 requiring more exposures to exhibit a sensitized response. Both lines show conditioned place preference for cocaine. We determined that the cocaine sensitivity phenotype in each RIX line was largely driven by the genetic influence of one CC parental strain, CC004/TauUnc and CC041/TauUnc. CC004 demonstrates active operant cocaine self-administration and CC041 is unable to acquire under the same testing conditions, a deficit which is specific to cocaine as both strains show operant response for a natural food reward. Examination of potential mechanisms driving differential responses to cocaine show strain differences in molecular and behavioral circadian rhythms. Additionally, while there is no difference in striatal dopamine tissue content or dynamics, there are selective differences in striatal norepinephrine and serotonergic tissue content., Conclusions: These CC strains offer a complex polygenic model system to study underlying mechanisms of cocaine response. We propose that CC041/TauUnc and CC004/TauUnc will be useful for studying genetic and biological mechanisms underlying resistance or vulnerability to the stimulatory and reinforcing effects of cocaine.

Introduction and Hypothesis: Patient history is often insufficient to identify type of urinary incontinence (UI). Multichannel urodynamic testing (UDS) is often used to clarify the diagnosis. Dynamic cystoscopy (DC) is a novel approach for testing bladder function. The primary objective of this study was to investigate the diagnostic agreement of UDS and DC in evaluating women with mixed urinary incontinence (MUI)., Methods: Women presenting with MUI were approached for enrollment if UDS and DC were planned for further investigation. Investigators were blinded to history and comparative test results. McNemar's test and kappa coefficient were calculated to assess agreement between UDS and DC. Receiver operating characteristic (ROC) analysis was used to explore the best possible filling sensation cutoffs for DC that would best predict the filling sensation cutoffs from UDS., Results: Sixty participants were included, of whom, four were excluded for protocol violation. For the primary outcome measure of agreement, UDS and DC were concordant in 44/56 of stress urinary incontinence (SUI) cases (79%) with a κ= 0.54 and in 43/56 of urinary urge incontinence (UUI) cases (77%) with a κ= 0.54, indicating moderate, nearly substantial agreement. ROC analysis identified the best prediction of DC first urge to void as 148 cm 3 , strong urge 215 cm 3 , and maximum capacity at 246 cm 3 . These parameters were used to compare UDS UUI to DC UUI and resulted in a κ = 0.61 (p = 0.37), indicating substantial agreement., Conclusions: When compared with UDS, DC shows moderate agreement for detection of SUI and substantial agreement for detection of UUI.

Background: Surgical coaching, with the goal of improving operative performance, has been introduced into residency and fellowship programs. This is the first systematic review on surgical coaching limited to randomized controlled trials. The objective of this review is to synthesize the existing evidence that addresses the following question: "What are the effects of surgical coaching to improve learner outcomes?", Methods: A comprehensive literature search was performed through the following databases: MEDLINE, EMBASE, ERIC, and Cochrane Central Register of Controlled Trials. The methodological quality of the selected randomized controlled trials was evaluated using the Cochrane Collaboration tool for assessing risk of bias., Results: Five randomized controlled trials were included in our final analysis. All five RCTs showed improvement in technical surgical performance after coaching. Two studies provided further evidence that skills were retained and one described the high satisfaction of learners. The risk of bias was low in 3 trials., Conclusions: Surgical coaching is associated with high learner satisfaction and improvements of skills and knowledge. The current evidence for surgical coaching programs is overwhelmingly positive., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Distal enhancers are thought to play important roles in the spatiotemporal regulation of gene expression during embryonic development, but few predicted enhancer elements have been shown to affect transcription of their endogenous genes or to alter phenotypes when disrupted. Here, we demonstrate that a 123.6-kb deletion within the mouse Slc25a13 gene is associated with reduced transcription of Dlx5 , a gene located 660 kb away. Mice homozygous for the Slc25a13 deletion mutation [named hyperspin ( hspn )] have malformed inner ears and are deaf with balance defects, whereas previously reported Slc25a13 knockout mice showed no phenotypic abnormalities. Inner ears of Slc25a13 hspn/hspn mice have malformations similar to those of Dlx5 - / - embryos, and Dlx5 expression is severely reduced in the otocyst but not the branchial arches of Slc25a13 hspn/hspn embryos, indicating that the Slc25a13 hspn deletion affects otic-specific enhancers of Dlx5 In addition, transheterozygous Slc25a13 +/hspn Dlx5 +/ - mice exhibit noncomplementation with inner ear dysmorphologies similar to those of Slc25a13 hspn/hspn and Dlx5 - / - embryos, verifying a cis -acting effect of the Slc25a13 hspn deletion on Dlx5 expression. CRISPR/Cas9-mediated deletions of putative enhancer elements located within the Slc25a13 hspn deleted region failed to phenocopy the defects of Slc25a13 hspn/hspn mice, suggesting the possibility of multiple enhancers with redundant functions. Our findings in mice suggest that analogous enhancer elements in the human SLC25A13 gene may regulate DLX5 expression and underlie the hearing loss that is associated with split-hand/-foot malformation 1 syndrome. Slc25a13 hspn/hspn mice provide a new animal model for studying long-range enhancer effects on Dlx5 expression in the developing inner ear., (Copyright © 2018 by the Genetics Society of America.)

Mutations of the human ATP6V1B1 gene cause distal renal tubular acidosis (dRTA; OMIM #267300) often associated with sensorineural hearing impairment; however, mice with a knockout mutation of Atp6v1b1 were reported to exhibit a compensated acidosis and normal hearing. We discovered a new spontaneous mutation (vortex, symbol vtx) of Atp6v1b1 in an MRL/MpJ (MRL) colony of mice. In contrast to the reported phenotype of the knockout mouse, which was developed on a primarily C57BL/6 (B6) strain background, MRL-Atp6v1b1vtx/vtx mutant mice exhibit profound hearing impairment, which is associated with enlarged endolymphatic compartments of the inner ear. Mutant mice have alkaline urine but do not exhibit overt metabolic acidosis, a renal phenotype similar to that of the Atpbv1b1 knockout mouse. The abnormal inner ear phenotype of MRL- Atp6v1b1vtx/vtx mice was lost when the mutation was transferred onto the C57BL/6J (B6) background, indicating the influence of strain-specific genetic modifiers. To genetically map modifier loci in Atp6v1b1vtx/vtx mice, we analysed ABR thresholds of progeny from a backcross segregating MRL and B6 alleles. We found statistically significant linkage with a locus on Chr 13 that accounts for about 20% of the hearing threshold variation in the backcross mice. The important effect that genetic background has on the inner ear phenotype of Atp6v1b1 mutant mice provides insight into the hearing loss variability associated with dRTA caused by ATP6V1B1 mutations. Because MRL-Atp6v1b1vxt/vtx mice do not recapitulate the metabolic acidosis of dRTA patients, they provide a new genetic model for nonsyndromic deafness with enlarged vestibular aqueduct (EVA; OMIM #600791)., (© The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

A single nucleotide variant (SNV) of the cadherin 23 gene (Cdh23 c.753A ), common to many inbred mouse strains, accelerates age-related hearing loss (AHL) and can worsen auditory phenotypes of other mutations. We used homologous recombination in C57BL/6 NJ (B6N) and 129S1/SvImJ (129S1) embryonic stem cells to engineer mouse strains with reciprocal single base pair substitutions (B6-Cdh23 c.753A>G and 129S1-Cdh23 c.753G>A ). We compared ABR thresholds and cochlear pathologies of these SNV mice with those of congenic (B6.129S1-Cdh23 Ahl+ and 129S1.B6-Cdh23 ahl ) and parental (B6N and 129S1) strain mice. Results verified the protective effect of the Cdh23 c.753G allele, which prevented high frequency hearing loss in B6 mice to at least 18 months of age, and the AHL-inducing effect of the Cdh23 c.753A allele, which worsened hearing loss in 129S1 mice. ABR thresholds differed between 129S-Cdh23 c.753A SNV and 129S1.B6-Cdh23 ahl congenic mice, and a linkage backcross involving these strains localized a Chr 10 QTL contributing to the difference. These results illustrate the large effects that strain background and congenic regions have on the hearing loss associated with Cdh23 c.753 alleles. Importantly, the B6-Cdh23 c.753G strain can be used to eliminate the confounding influence of the Cdh23 c.753A variant in hearing studies of B6 mice and mutant mice on the B6 background.

Introduction and Hypothesis: The primary objective of this study was to determine significant predictors of length of stay (LOS) beyond the first postoperative day after urogynecological surgery., Methods: A single-center retrospective cohort study was conducted in 2015. Our study population included women who underwent inpatient pelvic reconstructive surgery. The primary outcome was LOS beyond the first postoperative day. A logistic regression analysis explored the relationship between 11 selected predictor variables [age, body mass index (BMI), American Society of Anesthesiologists (ASA) score, distance from home to hospital, length of surgery, anesthesia during surgery, route of surgical approach, trial of void recordings, choice of bladder protocol, presence of concomitant sling, surgeon], and LOS., Results: Two hundred and sixty-three patients were included in this study. A logistic regression analysis identified route of surgery and trial of void recordings as the two statistically significant predictors of stay beyond the first postoperative day. The odds of LOS after laparoscopic or open surgery compared with vaginal surgery increased more than fivefold [laparoscopic vs. vaginal approach odds ratio (OR) 5.04, 95 % confidence interval (CI) 1.95-13.03; laparotomy vs. vaginal OR 15.56, 95 % CI 1.77-136.77] and more than threefold for a prolonged pass of the bladder protocol compared with an immediate pass (OR 3.25, 95 % CI 1.54-6.87)., Conclusion: Our study identified route of surgery and trial of void recordings as the two predictors with the greatest impact on LOS beyond the first postoperative day. Our results warrant a larger follow-up study.

Background: Antiretroviral therapy use in pregnancy, and specifically regimens containing protease inhibitors (PIs), has been associated with adverse infant outcomes including preterm birth (PTB), low birth weight (LBW) and small for gestational age (SGA) infants. However, there are conflicting results in the literature with respect to the degree of risk. These results may be related to demographic factors and confounding of maternal HIV infection and degree of immune suppression., Objective: The primary objective of our study was to assess the risk of PTB in HIV-positive pregnant women on ART compared to HIV-negative pregnant women. Secondary objectives included: comparing the risks of LBW and SGA infants in HIV-positive women on ART to HIV-negative pregnant women; comparing the risks of PTB, LBW and SGA in HIV-positive women on PI-based regimens compared to HIV-negative women., Methods: A retrospective matched cohort study of 384 women was conducted between 2007 and 2012 comparing outcomes of HIV-positive women on ART to HIV-negative women. Univariate and multivariable logistic regression models were used, adjusting for potential confounding factors, to compare the two groups on adverse infant outcomes., Results: Unadjusted odds ratios revealed a >2-fold increase in rates: PTB OR 2.6 [95% CI 1.3-5.1]; LBW OR 2.9 [95% CI 1.4-6.3]; SGA OR 2.5 [95% CI 1.3-4.7]. Once odds ratios were adjusted to account for race (p<0.01), our results were no longer statistically significant as this study was underpowered to detect smaller differences: PTB aOR 1.4 [95% CI 0.5-3.6]; LBW OR 1.9 [95% CI 0.6-5.5]; SGA OR 1.8 [95% CI 0.8-4.6]., Conclusion: Our preliminary results show an increase in PTB, LBW and SGA but due to lack of power, our adjusted results are not statistically significant. A larger prospective follow-up study is needed to further explore these findings in this population., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Adaptor protein (AP) complexes function in the intracellular sorting and vesicular transport of membrane proteins. The clathrin-associated AP-1 complex functions at the trans-Golgi network and endosomes, and some forms of this complex are thought to mediate the sorting of proteins in plasma membranes of polarized epithelial cells. A null mutation of the mouse Ap1g1 gene, which encodes the gamma-1 subunit of the AP-1 complex, causes embryonic lethality when homozygous, indicating its critical importance in early development but precluding studies of its possible roles during later stages. Here, we describe our analyses of a new spontaneous mutation of Ap1g1 named "figure eight" (symbol fgt) and show that it is an in-frame deletion of 6 bp, which results in the elimination of two amino acids of the encoded protein. In contrast to Ap1g1 (-/-) null mice, mice homozygous for the recessive fgt mutation are viable with adult survival similar to controls. Although Ap1g1 is ubiquitously expressed, the phenotype of Ap1g1 (fgt) mutant mice is primarily restricted to abnormalities in sensory epithelial cells of the inner ear, pigmented epithelial cells of the retina, follicular epithelial cells of the thyroid gland, and the germinal epithelium of the testis, suggesting that impaired AP-1 sorting and targeting of membrane proteins in these polarized cells may underlie the observed pathologies. Ap1g1 (fgt) mutant mice provide a new animal model to study the in vivo roles of gamma-1 adaptin and the AP-1 complex throughout development and to investigate factors that underlie its associated phenotypic abnormalities.

Introduction and Hypothesis: Our study piloted a novel, two-tiered approach to delivering pelvic floor muscle training (PFMT) to postpartum women involving a standardized group workshop followed by the opportunity to self-select for individual PFMT sessions. The aim of the study was to evaluate the outcomes in women who self-selected for individual PFMT using validated quality of life (QoL) questionnaires, the Pelvic Floor Distress Inventory-20 (PFDI-20), the Pelvic Floor Impact Questionnaire-7 (PFIQ-7), the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire-12 (PISQ-12), as well as the Modified Oxford Scale (MOS) for strength. Women's satisfaction with the program was also assessed., Methods: This was a single-center prospective cohort study conducted between December 2013 and September 2014. Changes from baseline to postintervention QoL and MOS scores were tested using the Wilcoxon signed-rank test., Results: Two hundred and eighteen women attended the workshop, 54 enrolled in PFMT sessions, and 50 completed follow-up. Significant improvements were seen in the PFDI-20 (mean change -41.8, p < 0.001) and PFIQ-7 (mean change -23.0, p < 0.001) questionnaires. Results for the PISQ-12 could not be tabulated, as there were too many missing responses. The MOS score was significantly improved from baseline (4; range {0-5} compared with 3; range {0-4}; p < 0.001). Forty-nine of 50 women's expectations for the program were met [9 of 10; standard deviation (SD) 1.4]., Conclusion: Results suggest that a two-tiered, self-selection approach to administering PFMT in the postpartum period contributes to significant improvements in pelvic floor function, QoL, MOS strength, and to high satisfaction rates.

Inbred mouse strains serve as important models for human presbycusis or age-related hearing loss. We previously mapped a locus (ahl8) contributing to the progressive hearing loss of DBA/2J (D2) mice and later showed that a missense variant of the Fscn2 gene, unique to the D2 inbred strain, was responsible for the ahl8 effect. Although ahl8 can explain much of the hearing loss difference between C57BL/6J (B6) and D2 strain mice, other loci also contribute. Here, we present results of our linkage analyses to map quantitative trait loci (QTLs) that modify the severity of hearing loss associated with the D2 strain Fscn2 (ahl8) allele. We searched for modifier loci by analyzing 31 BXD recombinant inbred (RI) lines fixed for the predisposing D2-derived Fscn2 (ahl8/ahl8) genotype and found a statistically significant linkage association of threshold means with a QTL on Chr 5, which we designated M5ahl8. The highest association (LOD 4.6) was with markers at the 84-90 Mb position of Chr 5, which could explain about 46 % of the among-RI strain variation in auditory brainstem response (ABR) threshold means. The semidominant nature of the modifying effect of M5ahl8 on the Fscn2 (ahl8/ahl8) phenotype was demonstrated by analysis of a backcross involving D2 and B6.D2-Chr11D/LusJ strain mice. The Chr 5 map position of M5ahl8 and the D2 origin of its susceptibility allele correspond to Tmc1m4, a previously reported QTL that modifies outer hair cell degeneration in Tmc1 (Bth) mutant mice, suggesting that M5ahl8 and Tmc1m4 may represent the same gene affecting maintenance of stereocilia structure and function during aging.

Thyroid hormone (TH) is essential for proper cochlear development and function, and TH deficiencies cause variable hearing impairment in humans and mice. Thyroid peroxidase (TPO) catalyzes key reactions in TH synthesis, and TPO mutations have been found to underlie many cases of congenital hypothyroidism in human patients. In contrast, only a single mutation of the mouse TPO gene has been reported previously (Tpo(R479C)) but was not evaluated for auditory function. Here, we describe and characterize two new mouse mutations of Tpo with an emphasis on their associated auditory deficits. Mice homozygous for these recessive mutations have dysplastic thyroid glands and lack detectable levels of TH. Because of the small size of mutant mice, the mutations were named teeny (symbol Tpo(tee)) and teeny-2 Jackson (Tpo(tee-2J)). Tpo(tee) is a single base-pair missense mutation that was induced by ENU, and Tpo(tee-2J) is a 64 bp intragenic deletion that arose spontaneously. The Tpo(tee) mutation changes the codon for a highly conserved tyrosine to asparagine (p.Y614N), and the Tpo(tee-2J) mutation deletes a splice donor site, which results in exon skipping and aberrant transcripts. Mutant mice are profoundly hearing impaired with auditory brainstem response (ABR) thresholds about 60 dB above those of non-mutant controls. The maturation of cochlear structures is delayed in mutant mice and tectorial membranes are abnormally thick. To evaluate the effect of genetic background on auditory phenotype, we produced a C3.B6-Tpo(tee-2J) congenic strain and found that ABR thresholds of mutant mice on the C3H/HeJ strain background are 10-12 dB lower than those of mutant mice on the C57BL/6 J background. The Tpo mutant strains described here provide new heritable mouse models of congenital hypothyroidism that will be valuable for future studies of thyroid hormones' role in auditory development and function.

Chloride intracellular channel 5 protein (CLIC5) was originally isolated from microvilli in complex with actin binding proteins including ezrin, a member of the Ezrin-Radixin-Moesin (ERM) family of membrane-cytoskeletal linkers. CLIC5 concentrates at the base of hair cell stereocilia and is required for normal hearing and balance in mice, but its functional significance is poorly understood. This study investigated the role of CLIC5 in postnatal development and maintenance of hair bundles. Confocal and scanning electron microscopy of CLIC5-deficient jitterbug (jbg) mice revealed progressive fusion of stereocilia as early as postnatal day 10. Radixin (RDX), protein tyrosine phosphatase receptor Q (PTPRQ), and taperin (TPRN), deafness-associated proteins that also concentrate at the base of stereocilia, were mislocalized in fused stereocilia of jbg mice. TPRQ and RDX were dispersed even prior to stereocilia fusion. Biochemical assays showed interaction of CLIC5 with ERM proteins, TPRN, and possibly myosin VI (MYO6). In addition, CLIC5 and RDX failed to localize normally in fused stereocilia of MYO6 mutant mice. Based on these findings, we propose a model in which these proteins work together as a complex to stabilize linkages between the plasma membrane and subjacent actin cytoskeleton at the base of stereocilia., (© Published 2013 Wiley Periodicals, Inc. This article is a US government work and, as such, is in the public domain in the United States of America.)

We previously mapped a locus (ahl4) on distal Chromosome 10 that contributes to the age-related hearing loss of A/J strain mice. Here, we report on a refined genetic map position for ahl4 and its association with a mutation in the citrate synthase gene (Cs). We mapped ahl4 to the distal-most 7 megabases (Mb) of chromosome 10 by analysis of a new linkage backcross and then further narrowed the interval to 5.5 Mb by analysis of 8 C57BL/6J congenic lines with different A/J-derived segments of chromosome 10. A nucleotide variant in exon 3 of Cs is the only known DNA difference within the ahl4 candidate gene interval that is unique to the A/J strain and that causes a nonsynonymous codon change. Multiple lines of evidence implicate this missense mutation (H55N) as the underlying cause of ahl4-related hearing loss, likely through its effects on mitochondrial adenosine trisphosphate (ATP) and free radical production in cochlear hair cells. The A/J mouse thus provides a new model system for in vivo studies of mitochondrial function and hearing loss., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Inbred strain variants of the Cdh23 gene have been shown to influence the onset and progression of age-related hearing loss (AHL) in mice. In linkage backcrosses, the recessive Cdh23 allele (ahl) of the C57BL/6J strain, when homozygous, confers increased susceptibility to AHL, while the dominant allele (Ahl+) of the CBA/CaJ strain confers resistance. To determine the isolated effects of these alleles on different strain backgrounds, we produced the reciprocal congenic strains B6.CBACa-Cdh23(Ahl)(+) and CBACa.B6-Cdh23(ahl) and tested 15-30 mice from each for hearing loss progression. ABR thresholds for 8 kHz, 16 kHz, and 32 kHz pure-tone stimuli were measured at 3, 6, 9, 12, 15 and 18 months of age and compared with age-matched mice of the C57BL/6J and CBA/CaJ parental strains. Mice of the C57BL/6N strain, which is the source of embryonic stem cells for the large International Knockout Mouse Consortium, were also tested for comparisons with C57BL/6J mice. Mice of the C57BL/6J and C57BL/6N strains exhibited identical hearing loss profiles: their 32 kHz ABR thresholds were significantly higher than those of CBA/CaJ and congenic strain mice by 6 months of age, and their 16 kHz thresholds were significantly higher by 12 months. Thresholds of the CBA/CaJ, the B6.CBACa-Cdh23(Ahl)(+), and the CBACa.B6-Cdh23(ahl) strain mice differed little from one another and only slightly increased throughout the 18-month test period. Hearing loss, which corresponded well with cochlear hair cell loss, was most profound in the C57BL/6J and C57BL/6NJ strains. These results indicate that the CBA/CaJ-derived Cdh23(Ahl)(+) allele dramatically lessens hearing loss and hair cell death in an otherwise C57BL/6J genetic background, but that the C57BL/6J-derived Cdh23(ahl) allele has little effect on hearing loss in an otherwise CBA/CaJ background. We conclude that although Cdh23(ahl) homozygosity is necessary, it is not by itself sufficient to account for the accelerated hearing loss of C57BL/6J mice., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Stereocilia, the modified microvilli projecting from the apical surfaces of the sensory hair cells of the inner ear, are essential to the mechanoelectrical transduction process underlying hearing and balance. The actin-filled stereocilia on each hair cell are tethered together by fibrous links to form a highly patterned hair bundle. Although many structural components of hair bundles have been identified, little is known about the signaling mechanisms that regulate their development, morphology, and maintenance. Here, we describe two naturally occurring, allelic mutations that result in hearing and balance deficits in mice, named roundabout (rda) and roundabout-2J (rda(2J)). Positional cloning identified both as mutations of the mouse ELMO domain containing 1 gene (Elmod1), a poorly characterized gene with no previously reported mutant phenotypes. The rda mutation is a 138 kb deletion that includes exons 1-5 of Elmod1, and rda(2J) is an intragenic duplication of exons 3-8 of Elmod1. The deafness associated with these mutations is caused by cochlear hair cell dysfunction, as indicated by conspicuous elongations and fusions of inner hair cell stereocilia and progressive degeneration of outer hair cell stereocilia. Mammalian ELMO-family proteins are known to be involved in complexes that activate small GTPases to regulate the actin cytoskeleton during phagocytosis and cell migration. ELMOD1 and ELMOD2 recently were shown to function as GTPase-activating proteins (GAPs) for the Arf family of small G proteins. Our finding connecting ELMOD1 deficiencies with stereocilia dysmorphologies thus establishes a link between the Ras superfamily of small regulatory GTPases and the actin cytoskeleton dynamics of hair cell stereocilia.

Thyroid hormone has pleiotropic effects on cochlear development, and genomic variation influences the severity of associated hearing deficits. DW/J-Pou1f1dw/dw mutant mice lack pituitary thyrotropin, which causes severe thyroid hormone deficiency and profound hearing impairment. To assess the genetic complexity of protective effects on hypothyroidism-induced hearing impairment, an F1 intercross was generated between DW/J-Pou1f1dw/+ carriers and an inbred strain with excellent hearing derived from Mus castaneus, CAST/EiJ. Approximately 24% of the (DW/J×CAST/EiJ) Pou1f1dw/dw F2 progeny had normal hearing. A genome scan revealed a locus on chromosome 2, named modifier of dw hearing, or Mdwh, that rescues hearing despite persistent hypothyroidism. This chromosomal region contains the modifier of tubby hearing 1 (Moth1) locus that encodes a protective allele of the microtubule-associated protein MTAP1A. DW/J-Pou1f1dw/+ carriers were crossed with the AKR strain, which also carries a protective allele of Mtap1a, and we found that AKR is not protective for hearing in the (DW/J×AKR) Pou1f1dw/dw F2 progeny. Thus, protective alleles of Mtap1a are not sufficient to rescue DW/J-Pou1f1dw/dw hearing. We expect that identification of protective modifiers will enhance our understanding of the mechanisms of hypothyroidism-induced hearing impairment.

Both the ahl allele of Cdh23 and the null mutation of Sod1 have been shown to contribute to age-related hearing loss (AHL) in mice, but mixed strain backgrounds have confounded analyses of their individual and combined effects. To test for the effects of Sod1 deficiency independently from those of Cdh23(ahl), we produced mice with four digenic genotypes: Sod1(+/+)Cdh23(ahl)(/ahl), Sod1(+/+)Cdh23(+/+), Sod1(-/-)Cdh23(ahl)(/ahl), and Sod1(-/-)Cdh23(+/+), all on a uniform C57BL(/)6J strain background. We assessed hearing loss by ABR threshold measurements and evaluated cochlear pathologies in age-matched mice of each digenic combination. ABR analysis showed that Sod1(+/+)Cdh23(+/+) mice retain normal hearing up to 15 months of age and that hearing loss of Sod1(+/+)Cdh23(ahl)(/ahl) mice is more age and frequency dependent than that of Sod1(-/-)Cdh23(+/+) mice. ABR results also showed that mice with both gene mutations (Sod1(-/-)Cdh23(ahl)(/ahl)) exhibit the earliest onset and most severe hearing loss, greater than predicted for strictly additive effects. Histological analysis of cochleas showed that hair cell lesions are most severe in Sod1(-)(/-)Cdh23(ahl)(/ahl) mice followed closely by Sod1(+)(/+)Cdh23(ahl)(/ahl) mice and much smaller in Sod1(-)(/-)Cdh23(+)(/+) and Sod1(+)(/+)Cdh23(+)(/+) mice. Despite extensive damage to cochlear hair cells, vestibular hair cells appeared remarkably normal in all strains. Although both Sod1(-/-) and Cdh23(ahl)(/ahl) genotypes had strong effects on hearing loss, the Cdh23(ahl/ahl) genotype was primarily responsible for the increase in hair cell loss, suggesting that the two mutations have different underlying mechanisms of pathology., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

The quantitative trait locus ahl8 is a key contributor to the early-onset, age-related hearing loss of DBA/2J mice. A nonsynonymous nucleotide substitution in the mouse fascin-2 gene (Fscn2) is responsible for this phenotype, confirmed by wild-type BAC transgene rescue of hearing loss in DBA/2J mice. In chickens and mice, FSCN2 protein is abundant in hair-cell stereocilia, the actin-rich structures comprising the mechanically sensitive hair bundle, and is concentrated toward stereocilia tips of the bundle's longest stereocilia. FSCN2 expression increases when these stereocilia differentially elongate, suggesting that FSCN2 controls filament growth, stiffens exposed stereocilia, or both. Because ahl8 accelerates hearing loss only in the presence of mutant cadherin 23, a component of hair-cell tip links, mechanotransduction and actin crosslinking must be functionally interrelated.

Recessive mutations at the mouse pirouette (pi) locus result in hearing loss and vestibular dysfunction due to neuroepithelial defects in the inner ear. Using a positional cloning strategy, we have identified mutations in the gene Grxcr1 (glutaredoxin cysteine-rich 1) in five independent allelic strains of pirouette mice. We also provide sequence data of GRXCR1 from humans with profound hearing loss suggesting that pirouette is a model for studying the mechanism of nonsyndromic deafness DFNB25. Grxcr1 encodes a 290 amino acid protein that contains a region of similarity to glutaredoxin proteins and a cysteine-rich region at its C terminus. Grxcr1 is expressed in sensory epithelia of the inner ear, and its encoded protein is localized along the length of stereocilia, the actin-filament-rich mechanosensory structures at the apical surface of auditory and vestibular hair cells. The precise architecture of hair cell stereocilia is essential for normal hearing. Loss of function of Grxcr1 in homozygous pirouette mice results in abnormally thin and slightly shortened stereocilia. When overexpressed in transfected cells, GRXCR1 localizes along the length of actin-filament-rich structures at the dorsal-apical surface and induces structures with greater actin filament content and/or increased lengths in a subset of cells. Our results suggest that deafness in pirouette mutants is associated with loss of GRXCR1 function in modulating actin cytoskeletal architecture in the developing stereocilia of sensory hair cells., (Copyright (c) 2010 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

The DBA/2J inbred strain of mice is used extensively in hearing research, yet little is known about the genetic basis for its early onset, progressive hearing loss. To map underlying genetic factors we analyzed recombinant inbred strains and linkage backcrosses. Analysis of 213 mice from 31 BXD recombinant inbred strains detected linkage of auditory brain-stem response thresholds with a locus on distal chromosome 11, which we designate ahl8. Analysis of 225 N2 mice from a backcross of (C57BL/6JxDBA/2J) F1 hybrids to DBA/2J mice confirmed this linkage (LOD>50) and refined the ahl8 candidate gene interval. Analysis of 214 mice from a backcross of (B6.CAST-Cdh23 Ahl+ xDBA/2J) F1 hybrids to DBA/2J mice demonstrated a genetic interaction of Cdh23 with ahl8. We conclude that ahl8 is a major contributor to the hearing loss of DBA/2J mice and that its effects are dependent on the predisposing Cdh23 ahl genotype of this strain.

Mutations of the otoferlin gene have been shown to underlie deafness disorders in humans and mice. Analyses of genetically engineered mice lacking otoferlin have demonstrated an essential role for this protein in vesicle exocytosis at the inner hair cell afferent synapse. Here, we report on the molecular and phenotypic characterization of a new ENU-induced missense mutation of the mouse otoferlin gene designated Otof(deaf5Jcs). The mutation is a single T to A base substitution in exon 10 of Otof that causes a non-conservative amino acid change of isoleucine to asparagine in the C2B domain of the protein. Although strong immunoreactivity with an otoferlin-specific antibody was detected in cochlear hair cells of wildtype mice, no expression was detected in mutant mice, indicating that the missense mutation has a severe effect on the stability of the protein and potentially its localization. Auditory brainstem response (ABR) analysis demonstrated that mice homozygous for the missense mutation are profoundly deaf, consistent with an essential role for otoferlin in inner hair cell neurotransmission. Vestibular-evoked potentials (VsEPs) of mutant mice, however, were equivalent to those of wildtype mice, indicating that otoferlin is unnecessary for vestibular function even though it is highly expressed in both vestibular and cochlear hair cells.

The Tmhs gene codes for a tetraspan transmembrane protein that is expressed in hair cell stereocilia. We previously showed that a spontaneous missense mutation of Tmhs underlies deafness and vestibular dysfunction in the hurry-scurry (hscy) mouse. Subsequently, mutations in the human TMHS gene were shown to be responsible for DFNB67, an autosomal recessive nonsyndromic deafness locus. Here we describe a genetically engineered null mutation of the mouse Tmhs gene (Tmhs ( tm1Kjn )) and show that its phenotype is identical to that of the hscy missense mutation, confirming the deleterious nature of the hscy cysteine-to-phenylalanine substitution. In the targeted null allele, the Tmhs promoter drives expression of a lacZ reporter gene. Visualization of beta-galactosidase activity in Tmhs ( tm1Kjn ) heterozygous mice indicates that Tmhs is highly expressed in the cochlear and vestibular hair cells of the inner ear. Expression is first detectable at E15.5, peaks around P0, decreases slightly at P6, and is absent by P15, a duration that supports the involvement of Tmhs in stereocilia development. Tmhs reporter gene expression also was detected in several cranial and cervical sensory ganglia, but not in the vestibular or spiral ganglia. We also describe a new nontargeted mutation of the Tmhs gene, hscy-2J, that causes abnormal splicing from a cryptic splice site within exon 2 and is predicted to produce a functionally null protein lacking 51 amino acids of the wild-type sequence.

Dual oxidases generate the hydrogen peroxide needed by thyroid peroxidase for the incorporation of iodine into thyroglobulin, an essential step in thyroid hormone synthesis. Mutations in the human dual oxidase 2 gene, DUOX2, have been shown to underlie several cases of congenital hypothyroidism. We report here the first mouse Duox2 mutation, which provides a new genetic model for studying the specific function of DUOX2 in the thyroid gland and in other organ systems where it is hypothesized to play a role. We mapped the new spontaneous mouse mutation to chromosome 2 and identified it as a T>G base pair change in exon 16 of Duox2. The mutation changes a highly conserved valine to glycine at amino acid position 674 (V674G) and was named "thyroid dyshormonogenesis" (symbol thyd) to signify a defect in thyroid hormone synthesis. Thyroid glands of mutant mice are goitrous and contain few normal follicles, and anterior pituitaries are dysplastic. Serum T(4) in homozygotes is about one-tenth the level of controls and is accompanied by a more than 100-fold increase in TSH. The weight of adult mutant mice is approximately half that of littermate controls, and serum IGF-I is reduced. The cochleae of mutant mice exhibit abnormalities characteristic of hypothyroidism, including a delayed formation of the inner sulcus and tunnel of Corti and an abnormally thickened tectorial membrane. Hearing thresholds of adult mutant mice are on average 50-60 decibels (dB) above those of controls.

Although CLIC5 is a member of the chloride intracellular channel protein family, its association with actin-based cytoskeletal structures suggests that it may play an important role in their assembly or maintenance. Mice homozygous for a new spontaneous recessive mutation of the Clic5 gene, named jitterbug (jbg), exhibit impaired hearing and vestibular dysfunction. The jbg mutation is a 97 bp intragenic deletion that causes skipping of exon 5, which creates a translational frame shift and premature stop codon. Western blot and immunohistochemistry results confirmed the predicted absence of CLIC5 protein in tissues of jbg/jbg mutant mice. Histological analysis of mutant inner ears revealed dysmorphic stereocilia and progressive hair cell degeneration. In wild-type mice, CLIC5-specific immunofluorescence was detected in stereocilia of both cochlear and vestibular hair cells and also along the apical surface of Kolliker's organ during cochlear development. Refined immunolocalization in rat and chicken vestibular hair cells showed that CLIC5 is limited to the basal region of the hair bundle, similar to the known location of radixin. Radixin immunostaining appeared reduced in hair bundles of jbg mutant mice. By mass spectrometry and immunoblotting, CLIC5 was shown to be expressed at high levels in stereocilia of the chicken utricle, in an approximate 1:1 molar ratio with radixin. These results suggest that CLIC5 associates with radixin in hair cell stereocilia and may help form or stabilize connections between the plasma membrane and the filamentous actin core.

In this study, a 4-item battery of core stability (CS) tests modeled on core stabilization activities used in training and rehabilitation research was developed, and a measurement schedule was established to maximize internal consistency and stability reliabilities. Specifically, we found that 4 test administrations on each of 4 days produced intraclass correlation coefficients that in most instances exceeded 0.90 and stability reliability coefficients on the third and fourth days of testing that exceeded 0.90 for 2 of the tests and 0.80 for the other 2. Thus, it is recommended that in future research, examiners administer the battery for at least 3 days and consider the data collected on day 3 as the best estimate of participant CS.

Mouse deafness mutations provide valuable models of human hearing disorders and entry points into molecular pathways important to the hearing process. A newly discovered mouse mutation named hurry-scurry (hscy) causes deafness and vestibular dysfunction. Scanning electron microscopy of cochleae from 8-day-old mutants revealed disorganized hair bundles, and by 50 days of age, many hair cells are missing. To positionally clone hscy, 1,160 F(2) mice were produced from an intercross of (C57BL/6-hscy x CAST/EiJ) F(1) hybrids, and the mutation was localized to a 182-kb region of chromosome 17. A missense mutation causing a critical cysteine to phenylalanine codon change was discovered in a previously undescribed gene within this candidate interval. The gene is predicted to encode an integral membrane protein with four transmembrane helices. A synthetic peptide designed from the predicted protein was used to produce specific polyclonal antibodies, and strong immunoreactivity was observed on hair bundles of both inner and outer hair cells in cochleae of newborn +/+ controls and +/hscy heterozygotes but was absent in hscy/hscy mutants. Accordingly, the gene was given the name "tetraspan membrane protein of hair cell stereocilia," symbol Tmhs. Two related proteins (>60% amino acid identity) are encoded by genes on mouse chromosomes 5 and 6 and, together with the Tmhs-encoded protein (TMHS), comprise a distinct tetraspan subfamily. Our localization of TMHS to the apical membrane of inner ear hair cells during the period of stereocilia formation suggests a function in hair bundle morphogenesis.

X-linked hypophosphatemic rickets (XLH) in humans is caused by mutation in the PHEX gene. Previously, three mutations in the mouse Phex gene have been reported: Phex(Hyp), Gy, and Phex(Ska1). Here we report analysis of two new spontaneous mutation in the mouse Phex gene, Phex(Hyp-2J) and Phex(Hyp-Duk). Phex(Hyp-2J) and Phex(Hyp-Duk) involve intragenic deletions of at least 7.3 kb containing exon 15, and 30 kb containing exons 13 and 14, respectively. Both mutations cause similar phenotypes in males, including shortened hind legs and tail, a shortened square trunk, hypophosphatemia, hypocalcemia, and rachitic bone disease. In addition, mice carrying the Phex(Hyp-Duk) mutation exhibit background-dependent variable expression of deafness, circling behavior, and cranial dysmorphology, demonstrating the influence of modifying genes on Phex-related phenotypes. Cochlear cross-sections from Phex(Hyp-2J)/Y and Phex(Hyp-Duk)/Y males reveal a thickening of the temporal bones surrounding the cochlea with the presence of a precipitate in the scala tympani. Evidence of the degeneration of the organ of Corti and spiral ganglion also are present in the hearing-impaired Phex(Hyp-Duk)/Y mice, but not in the normal-hearing Phex(Hyp-2J)/Y mice. Analysis of the phenotypes noted in Phex(Hyp-Duk)/Y and Phex(Hyp-2J)/Y males, together with those noted in Phex(Ska1)/Y and Phex(Hyp)/Y males, now allow XLH-related phenotypes to be separated from non-XLH-related phenotypes, such as those noted in Gy/Y males. Also, identification of the genetic modifiers of hearing and craniofacial dysmorphology in Phex(Hyp-Duk)/Y mice could provide insight into the phenotypic variation of XLH in humans.

We mapped two new recessive mutations causing circling behavior and deafness to the same region on chromosome 7 and showed they are allelic by complementation analysis. One was named 'deaf circler' (allele symbol dfcr) and the other 'deaf circler 2 Jackson' (allele symbol dfcr-2J). Both were shown to be mutations of the Ush1c gene, the mouse ortholog of the gene responsible for human Usher syndrome type IC and for the non-syndromic deafness disorder DFNB18. The Ush1c gene contains 28 exons, 20 that are constitutive and eight that are alternatively spliced. The dfcr mutation is a 12.8 kb intragenic deletion that eliminates three constitutive and five alternatively spliced exons. The dfcr-2J mutation is a 1 bp deletion in an alternatively spliced exon that creates a transcriptional frame shift, changing 38 amino acid codons before introducing a premature stop codon. Both mutations cause congenital deafness and severe balance deficits due to inner ear dysfunction. The stereocilia of cochlear hair cells are disorganized and splayed in mutant mice, with subsequent degeneration of the hair cells and spiral ganglion cells. Harmonin, the protein encoded by Ush1c, has been shown to bind, by means of its PDZ-domains, with the products of other Usher syndrome genes, including Myo7a, Cdh23 and Sans. The complexes formed by these protein interactions are thought to be essential for maintaining the integrity of hair cell stereocilia. The Ush1c mutant mice described here provide a means to directly investigate these interactions in vivo and to evaluate gene structure-function relationships that affect inner ear and eye phenotypes.

Mutations in the mouse dreher (dr) gene cause skeletal defects, hyperactivity, abnormal gait, deafness, white belly spotting, and hypoplasia of Müllerian duct derivatives. To map dr to high resolution, we utilized two crosses. Initially, we analyzed an intersubspecific intercross to construct a detailed genetic map of simple sequence length polymorphism markers within a 6.3-cM region surrounding the dr locus. Subsequently, we analyzed a second intersubspecific intercross segregating for the dr(6J) allele, which positioned dr within a 0.13-cM region between Rxrg and D1Mit370. A physical contig of BAC clones spanning the dr critical region was constructed, and eight potential dr candidate genes were excluded by genetic or physical mapping. Together these results lay the foundation for positional cloning of the dr gene., (Copyright 1999 Academic Press.)