Effect of sloped walking on lower limb muscle forces

Publication date: Available online 20 April 2016
Source:Gait & Posture
Author(s): Nathalie Alexander, Hermann Schwameder
Lower limb joint loadings are increased during sloped walking compared to level walking and muscle forces are major contributors to lower limb joint forces. Therefore, the aim of this study was to analyse lower limb muscle forces during sloped walking at different inclinations. Eighteen healthy male participants (27.0±4.7 y, 1.80±0.05m, 74.5±8.2kg) walked at a pre-set speed of 1.1m/s on a ramp at the inclinations of 0°,±6°,±12° and±18°. Kinematic data were captured with a motion capture system and kinetic data were recorded with two force plates imbedded into the ramp. A musculoskeletal model was used to compute lower limb muscle forces (normalized to body weight and gait cycle duration). During downhill walking gluteus maximus, quadriceps, soleus, peroneus and tibialis anterior muscle forces increased (p≤0.002) compared to level walking, while gluteus minimus, piriformis, adductor, iliopsoas, hamstrings and gastrocnemii muscle forces decreased (p≤0.002). Uphill walking decreased gluteus minimus, iliopsoas and tibialis anterior muscle forces (p≤0.002), while all other muscle forces increased (p≤0.002, except gluteus medius). Joint-muscle-force waveforms provided information on possible muscle contributions to joint compression forces. The most important muscles were: gluteus medius for hip forces, quadriceps and gastrocnemii for tibiofemoral forces, quadriceps for patellofemoral forces and triceps surae for ankle forces. The contribution of each muscle changed with the inclination during sloped walking compared to level walking. The current study provided important information on muscle forces during sloped walking that can be useful for rehabilitation and training procedures.



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Supraspinal control of automatic postural responses in people with multiple sclerosis

Publication date: Available online 20 April 2016
Source:Gait & Posture
Author(s): D.S. Peterson, G. Gera, F.B. Horak, B.W. Fling
The neural underpinnings of delayed automatic postural responses in people with multiple sclerosis (PwMS) are unclear. We assessed whether white matter pathways of two supraspinal regions (the cortical proprioceptive Broadman's Area-3; and the balance/locomotor-related pedunculopontine nucleus) were related to delayed postural muscle response latencies in response to external perturbations. 19 PwMS (48.8±11.4years; EDSS=3.5 (range: 2-4)) and 12 healthy adults (51.7±12.2years) underwent 20 discrete, backward translations of a support surface. Onset latency of agonist (medial-gastrocnemius) and antagonist (tibialis anterior) muscles were assessed. Diffusion tensor imaging assessed white-matter integrity (i.e. radial diffusivity) of cortical proprioceptive and balance/locomotor-related tracts. Latency of the tibialis anterior, but not medial gastrocnemius was larger in PwMS than control subjects (p=0.012 and 0.071, respectively). Radial diffusivity of balance/locomotor tracts was higher (worse) in PwMS than control subjects (p=0.004), and was significantly correlated with tibialis (p=0.002), but not gastrocnemius (p=0.06) onset latency. Diffusivity of cortical proprioceptive tracts were not correlated with muscle onset. Lesions in supraspinal structures including the pedunculopontine nucleus balance/locomotor network may contribute to delayed onset of postural muscle activity in PwMS, contributing to balance deficits in PwMS.



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Effect of sloped walking on lower limb muscle forces

Publication date: Available online 20 April 2016
Source:Gait & Posture
Author(s): Nathalie Alexander, Hermann Schwameder
Lower limb joint loadings are increased during sloped walking compared to level walking and muscle forces are major contributors to lower limb joint forces. Therefore, the aim of this study was to analyse lower limb muscle forces during sloped walking at different inclinations. Eighteen healthy male participants (27.0±4.7 y, 1.80±0.05m, 74.5±8.2kg) walked at a pre-set speed of 1.1m/s on a ramp at the inclinations of 0°,±6°,±12° and±18°. Kinematic data were captured with a motion capture system and kinetic data were recorded with two force plates imbedded into the ramp. A musculoskeletal model was used to compute lower limb muscle forces (normalized to body weight and gait cycle duration). During downhill walking gluteus maximus, quadriceps, soleus, peroneus and tibialis anterior muscle forces increased (p≤0.002) compared to level walking, while gluteus minimus, piriformis, adductor, iliopsoas, hamstrings and gastrocnemii muscle forces decreased (p≤0.002). Uphill walking decreased gluteus minimus, iliopsoas and tibialis anterior muscle forces (p≤0.002), while all other muscle forces increased (p≤0.002, except gluteus medius). Joint-muscle-force waveforms provided information on possible muscle contributions to joint compression forces. The most important muscles were: gluteus medius for hip forces, quadriceps and gastrocnemii for tibiofemoral forces, quadriceps for patellofemoral forces and triceps surae for ankle forces. The contribution of each muscle changed with the inclination during sloped walking compared to level walking. The current study provided important information on muscle forces during sloped walking that can be useful for rehabilitation and training procedures.



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Supraspinal control of automatic postural responses in people with multiple sclerosis

Publication date: Available online 20 April 2016
Source:Gait & Posture
Author(s): D.S. Peterson, G. Gera, F.B. Horak, B.W. Fling
The neural underpinnings of delayed automatic postural responses in people with multiple sclerosis (PwMS) are unclear. We assessed whether white matter pathways of two supraspinal regions (the cortical proprioceptive Broadman's Area-3; and the balance/locomotor-related pedunculopontine nucleus) were related to delayed postural muscle response latencies in response to external perturbations. 19 PwMS (48.8±11.4years; EDSS=3.5 (range: 2-4)) and 12 healthy adults (51.7±12.2years) underwent 20 discrete, backward translations of a support surface. Onset latency of agonist (medial-gastrocnemius) and antagonist (tibialis anterior) muscles were assessed. Diffusion tensor imaging assessed white-matter integrity (i.e. radial diffusivity) of cortical proprioceptive and balance/locomotor-related tracts. Latency of the tibialis anterior, but not medial gastrocnemius was larger in PwMS than control subjects (p=0.012 and 0.071, respectively). Radial diffusivity of balance/locomotor tracts was higher (worse) in PwMS than control subjects (p=0.004), and was significantly correlated with tibialis (p=0.002), but not gastrocnemius (p=0.06) onset latency. Diffusivity of cortical proprioceptive tracts were not correlated with muscle onset. Lesions in supraspinal structures including the pedunculopontine nucleus balance/locomotor network may contribute to delayed onset of postural muscle activity in PwMS, contributing to balance deficits in PwMS.



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Effect of sloped walking on lower limb muscle forces

Publication date: Available online 20 April 2016
Source:Gait & Posture
Author(s): Nathalie Alexander, Hermann Schwameder
Lower limb joint loadings are increased during sloped walking compared to level walking and muscle forces are major contributors to lower limb joint forces. Therefore, the aim of this study was to analyse lower limb muscle forces during sloped walking at different inclinations. Eighteen healthy male participants (27.0±4.7 y, 1.80±0.05m, 74.5±8.2kg) walked at a pre-set speed of 1.1m/s on a ramp at the inclinations of 0°,±6°,±12° and±18°. Kinematic data were captured with a motion capture system and kinetic data were recorded with two force plates imbedded into the ramp. A musculoskeletal model was used to compute lower limb muscle forces (normalized to body weight and gait cycle duration). During downhill walking gluteus maximus, quadriceps, soleus, peroneus and tibialis anterior muscle forces increased (p≤0.002) compared to level walking, while gluteus minimus, piriformis, adductor, iliopsoas, hamstrings and gastrocnemii muscle forces decreased (p≤0.002). Uphill walking decreased gluteus minimus, iliopsoas and tibialis anterior muscle forces (p≤0.002), while all other muscle forces increased (p≤0.002, except gluteus medius). Joint-muscle-force waveforms provided information on possible muscle contributions to joint compression forces. The most important muscles were: gluteus medius for hip forces, quadriceps and gastrocnemii for tibiofemoral forces, quadriceps for patellofemoral forces and triceps surae for ankle forces. The contribution of each muscle changed with the inclination during sloped walking compared to level walking. The current study provided important information on muscle forces during sloped walking that can be useful for rehabilitation and training procedures.



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Supraspinal control of automatic postural responses in people with multiple sclerosis

Publication date: Available online 20 April 2016
Source:Gait & Posture
Author(s): D.S. Peterson, G. Gera, F.B. Horak, B.W. Fling
The neural underpinnings of delayed automatic postural responses in people with multiple sclerosis (PwMS) are unclear. We assessed whether white matter pathways of two supraspinal regions (the cortical proprioceptive Broadman's Area-3; and the balance/locomotor-related pedunculopontine nucleus) were related to delayed postural muscle response latencies in response to external perturbations. 19 PwMS (48.8±11.4years; EDSS=3.5 (range: 2-4)) and 12 healthy adults (51.7±12.2years) underwent 20 discrete, backward translations of a support surface. Onset latency of agonist (medial-gastrocnemius) and antagonist (tibialis anterior) muscles were assessed. Diffusion tensor imaging assessed white-matter integrity (i.e. radial diffusivity) of cortical proprioceptive and balance/locomotor-related tracts. Latency of the tibialis anterior, but not medial gastrocnemius was larger in PwMS than control subjects (p=0.012 and 0.071, respectively). Radial diffusivity of balance/locomotor tracts was higher (worse) in PwMS than control subjects (p=0.004), and was significantly correlated with tibialis (p=0.002), but not gastrocnemius (p=0.06) onset latency. Diffusivity of cortical proprioceptive tracts were not correlated with muscle onset. Lesions in supraspinal structures including the pedunculopontine nucleus balance/locomotor network may contribute to delayed onset of postural muscle activity in PwMS, contributing to balance deficits in PwMS.



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Feasibility of a Recasting and Auditory Bombardment Treatment With Young Cochlear Implant Users

Purpose

There is little to guide clinicians in terms of evidence-based interventions for children with cochlear implants who demonstrate morpheme errors. This feasibility study tested the utility of a treatment targeting grammatical morpheme errors.

Method

Three children (ages 4–5 years) received Enhanced Conversational Recast treatment, a version of conversational recast treatment that focuses on a single morpheme error at a time, emphasizes attention to clinician input, and uses high linguistic variability with clinician input. A period of recasting was followed by 24 auditory presentations of the target morpheme in short sentences. After an initial baseline period, children were treated in individual sessions over 21–26 days.

Results

All children showed improved use of targeted grammatical morpheme use, both in elicited contexts and in terms of spontaneous use. Spontaneous use was best for the 2 children who were implanted earliest and whose audiograms showed the best hearing postimplant. Performance by a 3rd child diagnosed with auditory neuropathy spectrum disorder was more variable but still showed positive change.

Conclusions

The results indicate that the treatment can be effective for children with cochlear implants. The pattern of results across children also suggests potential variables that may moderate treatment effects.

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A Prekindergarten Curriculum Supplement for Enhancing Mainstream American English Knowledge in Nonmainstream American English Speakers

Purpose

The purpose of this study was to evaluate the efficacy of a curriculum supplement designed to enhance awareness of Mainstream American English (MAE) in African American English- (AAE-) speaking prekindergarten children.

Method

Children in 2 Head Start classrooms participated in the study. The experimental classroom received the Talking and Learning for Kindergarten program (Edwards, Rosin, Gross, & Chen, 2013), which used contrastive analysis to highlight morphological, phonological, and pragmatic differences between MAE and AAE. The control classroom received the Kindness Curriculum (Flook, Goldberg, Pinger, & Davidson, 2014), which was designed to promote mindfulness and emotional self-regulation. The amount of instruction was the same across the 2 programs. Both classrooms participated in pre- and posttest assessments.

Results

Children in the experimental classroom, but not the control classroom, showed significant improvement in 3 norm-referenced measures of phonological awareness and in an experimental measure that evaluated comprehension of words that are ambiguous in AAE, but unambiguous in MAE, because of morphological and phonological differences between the 2 dialects.

Conclusion

Although more research needs to be done on the efficacy of the Talking and Learning for Kindergarten program, these results suggest that it is possible to enhance AAE-speaking children's awareness of MAE prior to kindergarten entry.

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Affix Meaning Knowledge in First Through Third Grade Students

Purpose

We examined grade-level differences in 1st- through 3rd-grade students' performance on an experimenter-developed affix meaning task (AMT) and determined whether AMT performance explained unique variance in word-level reading and reading comprehension, beyond other known contributors to reading development.

Method

Forty students at each grade level completed an assessment battery that included measures of phonological awareness, receptive vocabulary, word-level reading, reading comprehension, and affix meaning knowledge.

Results

On the AMT, 1st-grade students were significantly less accurate than 2nd- and 3rd-grade students; there was no significant difference in performance between the 2nd- and 3rd-grade students. Regression analyses revealed that the AMT accounted for 8% unique variance of students' performance on word-level reading measures and 6% unique variance of students' performance on the reading comprehension measure, after age, phonological awareness, and receptive vocabulary were explained.

Conclusion

These results provide initial information on the development of affix meaning knowledge via an explicit measure in 1st- through 3rd-grade students and demonstrate that affix meaning knowledge uniquely contributes to the development of reading abilities above other known literacy predictors. These findings provide empirical support for how students might use morphological problem solving to read unknown multimorphemic words successfully.

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Feasibility of a Recasting and Auditory Bombardment Treatment With Young Cochlear Implant Users

Purpose

There is little to guide clinicians in terms of evidence-based interventions for children with cochlear implants who demonstrate morpheme errors. This feasibility study tested the utility of a treatment targeting grammatical morpheme errors.

Method

Three children (ages 4–5 years) received Enhanced Conversational Recast treatment, a version of conversational recast treatment that focuses on a single morpheme error at a time, emphasizes attention to clinician input, and uses high linguistic variability with clinician input. A period of recasting was followed by 24 auditory presentations of the target morpheme in short sentences. After an initial baseline period, children were treated in individual sessions over 21–26 days.

Results

All children showed improved use of targeted grammatical morpheme use, both in elicited contexts and in terms of spontaneous use. Spontaneous use was best for the 2 children who were implanted earliest and whose audiograms showed the best hearing postimplant. Performance by a 3rd child diagnosed with auditory neuropathy spectrum disorder was more variable but still showed positive change.

Conclusions

The results indicate that the treatment can be effective for children with cochlear implants. The pattern of results across children also suggests potential variables that may moderate treatment effects.

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A Prekindergarten Curriculum Supplement for Enhancing Mainstream American English Knowledge in Nonmainstream American English Speakers

Purpose

The purpose of this study was to evaluate the efficacy of a curriculum supplement designed to enhance awareness of Mainstream American English (MAE) in African American English- (AAE-) speaking prekindergarten children.

Method

Children in 2 Head Start classrooms participated in the study. The experimental classroom received the Talking and Learning for Kindergarten program (Edwards, Rosin, Gross, & Chen, 2013), which used contrastive analysis to highlight morphological, phonological, and pragmatic differences between MAE and AAE. The control classroom received the Kindness Curriculum (Flook, Goldberg, Pinger, & Davidson, 2014), which was designed to promote mindfulness and emotional self-regulation. The amount of instruction was the same across the 2 programs. Both classrooms participated in pre- and posttest assessments.

Results

Children in the experimental classroom, but not the control classroom, showed significant improvement in 3 norm-referenced measures of phonological awareness and in an experimental measure that evaluated comprehension of words that are ambiguous in AAE, but unambiguous in MAE, because of morphological and phonological differences between the 2 dialects.

Conclusion

Although more research needs to be done on the efficacy of the Talking and Learning for Kindergarten program, these results suggest that it is possible to enhance AAE-speaking children's awareness of MAE prior to kindergarten entry.

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Affix Meaning Knowledge in First Through Third Grade Students

Purpose

We examined grade-level differences in 1st- through 3rd-grade students' performance on an experimenter-developed affix meaning task (AMT) and determined whether AMT performance explained unique variance in word-level reading and reading comprehension, beyond other known contributors to reading development.

Method

Forty students at each grade level completed an assessment battery that included measures of phonological awareness, receptive vocabulary, word-level reading, reading comprehension, and affix meaning knowledge.

Results

On the AMT, 1st-grade students were significantly less accurate than 2nd- and 3rd-grade students; there was no significant difference in performance between the 2nd- and 3rd-grade students. Regression analyses revealed that the AMT accounted for 8% unique variance of students' performance on word-level reading measures and 6% unique variance of students' performance on the reading comprehension measure, after age, phonological awareness, and receptive vocabulary were explained.

Conclusion

These results provide initial information on the development of affix meaning knowledge via an explicit measure in 1st- through 3rd-grade students and demonstrate that affix meaning knowledge uniquely contributes to the development of reading abilities above other known literacy predictors. These findings provide empirical support for how students might use morphological problem solving to read unknown multimorphemic words successfully.

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Feasibility of a Recasting and Auditory Bombardment Treatment With Young Cochlear Implant Users

Purpose

There is little to guide clinicians in terms of evidence-based interventions for children with cochlear implants who demonstrate morpheme errors. This feasibility study tested the utility of a treatment targeting grammatical morpheme errors.

Method

Three children (ages 4–5 years) received Enhanced Conversational Recast treatment, a version of conversational recast treatment that focuses on a single morpheme error at a time, emphasizes attention to clinician input, and uses high linguistic variability with clinician input. A period of recasting was followed by 24 auditory presentations of the target morpheme in short sentences. After an initial baseline period, children were treated in individual sessions over 21–26 days.

Results

All children showed improved use of targeted grammatical morpheme use, both in elicited contexts and in terms of spontaneous use. Spontaneous use was best for the 2 children who were implanted earliest and whose audiograms showed the best hearing postimplant. Performance by a 3rd child diagnosed with auditory neuropathy spectrum disorder was more variable but still showed positive change.

Conclusions

The results indicate that the treatment can be effective for children with cochlear implants. The pattern of results across children also suggests potential variables that may moderate treatment effects.

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A Prekindergarten Curriculum Supplement for Enhancing Mainstream American English Knowledge in Nonmainstream American English Speakers

Purpose

The purpose of this study was to evaluate the efficacy of a curriculum supplement designed to enhance awareness of Mainstream American English (MAE) in African American English- (AAE-) speaking prekindergarten children.

Method

Children in 2 Head Start classrooms participated in the study. The experimental classroom received the Talking and Learning for Kindergarten program (Edwards, Rosin, Gross, & Chen, 2013), which used contrastive analysis to highlight morphological, phonological, and pragmatic differences between MAE and AAE. The control classroom received the Kindness Curriculum (Flook, Goldberg, Pinger, & Davidson, 2014), which was designed to promote mindfulness and emotional self-regulation. The amount of instruction was the same across the 2 programs. Both classrooms participated in pre- and posttest assessments.

Results

Children in the experimental classroom, but not the control classroom, showed significant improvement in 3 norm-referenced measures of phonological awareness and in an experimental measure that evaluated comprehension of words that are ambiguous in AAE, but unambiguous in MAE, because of morphological and phonological differences between the 2 dialects.

Conclusion

Although more research needs to be done on the efficacy of the Talking and Learning for Kindergarten program, these results suggest that it is possible to enhance AAE-speaking children's awareness of MAE prior to kindergarten entry.

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Affix Meaning Knowledge in First Through Third Grade Students

Purpose

We examined grade-level differences in 1st- through 3rd-grade students' performance on an experimenter-developed affix meaning task (AMT) and determined whether AMT performance explained unique variance in word-level reading and reading comprehension, beyond other known contributors to reading development.

Method

Forty students at each grade level completed an assessment battery that included measures of phonological awareness, receptive vocabulary, word-level reading, reading comprehension, and affix meaning knowledge.

Results

On the AMT, 1st-grade students were significantly less accurate than 2nd- and 3rd-grade students; there was no significant difference in performance between the 2nd- and 3rd-grade students. Regression analyses revealed that the AMT accounted for 8% unique variance of students' performance on word-level reading measures and 6% unique variance of students' performance on the reading comprehension measure, after age, phonological awareness, and receptive vocabulary were explained.

Conclusion

These results provide initial information on the development of affix meaning knowledge via an explicit measure in 1st- through 3rd-grade students and demonstrate that affix meaning knowledge uniquely contributes to the development of reading abilities above other known literacy predictors. These findings provide empirical support for how students might use morphological problem solving to read unknown multimorphemic words successfully.

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Atmospheric Pressure and Onset of Episodes of Menières Disease - A Repeated Measures Study

by Robert Gürkov, Ralf Strobl, Nina Heinlin, Eike Krause, Bernhard Olzowy, Christina Koppe, Eva Grill

Background

External changes of air pressure are transmitted to the middle and inner ear and may be used therapeutically in Menière’s disease, one of the most common vertigo disorders. We analyzed the possible relationship of atmospheric pressure and other meteorological parameters with the onset of MD vertigo episodes in order to determine whether atmospheric pressure changes play a role in the occurrence of MD episodes.

Methods

Patients of a tertiary outpatient dizziness clinic diagnosed with MD were asked to keep a daily vertigo diary to document MD episodes (2004–2009). Local air pressure, absolute temperature and dew point temperature were acquired on an hourly basis. Change in meteorological parameters was conceptualized as the maximum difference in a 24 hour time frame preceding each day. Effects were estimated using additive mixed models with a random participant effect. We included lagged air parameters, age, sex, weekday and season in the model.

Results

A total of 56 persons (59% female) with mean age 54 years were included. Mean follow-up time was 267 days. Persons experienced on average 10.3 episodes during the observation period (median 8). Age and change in air pressure were significantly associated with vertigo onset risk (Odds Ratio = 0.979 and 1.010). We could not show an effect of sex, weekday, season, air temperature, and dew point temperature.

Conclusions

Change in air pressure was significantly associated with onset of MD episodes, suggesting a potential triggering mechanism in the inner ear. MD patients may possibly use air pressure changes as an early warning system for vertigo attacks in the future.

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Inhibitors of Histone Deacetylases Attenuate Noise-Induced Hearing Loss

Abstract

Loss of auditory sensory hair cells is the major pathological feature of noise-induced hearing loss (NIHL). Currently, no established clinical therapies for prevention or amelioration of NIHL are available. The absence of treatments is due to our lack of a comprehensive understanding of the molecular mechanisms underlying noise-induced damage. Our previous study indicates that epigenetic modification of histones alters hair cell survival. In this study, we investigated the effect of noise exposure on histone H3 lysine 9 acetylation (H3K9ac) in the inner ear of adult CBA/J mice and determined if inhibition of histone deacetylases by systemic administration of suberoylanilide hydroxamic acid (SAHA) could attenuate NIHL. Our results showed that H3K9ac was decreased in the nuclei of outer hair cells (OHCs) and marginal cells of the stria vascularis in the basal region after exposure to a traumatic noise paradigm known to induce permanent threshold shifts (PTS). Consistent with these results, levels of histone deacetylases 1, 2, and 3 (HDAC1, HDAC2 and HDAC3) were increased predominately in the nuclei of cochlear cells. Silencing of HDAC1, HDAC2, or HDAC3 with siRNA reduced the expression of the target HDAC in OHCs, but did not attenuate noise-induced PTS, whereas treatment with the pan-HDAC inhibitor SAHA, also named vorinostat, reduced OHC loss, and attenuated PTS. These findings suggest that histone acetylation is involved in the pathogenesis of noise-induced OHC death and hearing loss. Pharmacological targeting of histone deacetylases may afford a strategy for protection against NIHL.

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ACOUSTICAL NEWSUSA

Abstract not available.

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A study of Helmholtz resonators to stabilize thermoacoustically driven pressure oscillations

This paper studies passive control of thermoacoustic instabilities from an unconventional mathematical perspective. These instabilities are notoriously known to result from the complex dynamic exchange between the unsteady heat release and the acoustic waves within a finite volume such as a combustor. One possible passive control strategy is to utilize Helmholtz resonators. Under certain simplifications, the ensemble combustion dynamics including the resonators reduces to a linear-time invariant–multiple time-delayed system (LTI–MTDS). As the main contribution of the paper, an exact analytical procedure is proposed to determine the placement of the resonators to avoid instabilities. A unique mathematical paradigm, called the cluster treatment of characteristic roots, is used to accomplish this task. It declares exactly the necessary and sufficient stability conditions for an LTI–MTDS in the space of the system parameters. This concept paper is written with the mindset that this analytical tool can invite yet unexplored design capabilities for similar noise control applications where acoustic dampers are used.

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Labyrinthine concussion following gunshot injury: A case report.

Related Articles

Labyrinthine concussion following gunshot injury: A case report.

Int J Audiol. 2016 Apr 19;:1-4

Authors: Bogle JM, Barrs D, Wester M, Davis L, Cevette MJ

Abstract
OBJECTIVE: Labyrinthine concussion due to a postauricular gunshot wound has not been well reported.
DESIGN: Retrospective chart review.
STUDY SAMPLE: We describe an otherwise healthy 22-year-old male who received a gunshot wound to the left mastoid and subsequently reported hearing loss and rotational vertigo.
RESULTS: Audiometric testing demonstrated significant inverted scoop shaped sensorineural hearing loss. Vestibular diagnostic testing indicated a significant uncompensated left peripheral vestibulopathy. Imaging demonstrated no structural changes to the middle ear or labyrinth, suggesting that the auditory and vestibular losses noted on diagnostic examination were likely due to labyrinthine concussion.
CONCLUSIONS: Labyrinthine concussion may lead to reduced vestibular reflex pathway following gunshot wounds to the temporal bone. Clinical presentation is likely to vary significantly among cases.

PMID: 27092730 [PubMed - as supplied by publisher]

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Labyrinthine concussion following gunshot injury: A case report.

Related Articles

Labyrinthine concussion following gunshot injury: A case report.

Int J Audiol. 2016 Apr 19;:1-4

Authors: Bogle JM, Barrs D, Wester M, Davis L, Cevette MJ

Abstract
OBJECTIVE: Labyrinthine concussion due to a postauricular gunshot wound has not been well reported.
DESIGN: Retrospective chart review.
STUDY SAMPLE: We describe an otherwise healthy 22-year-old male who received a gunshot wound to the left mastoid and subsequently reported hearing loss and rotational vertigo.
RESULTS: Audiometric testing demonstrated significant inverted scoop shaped sensorineural hearing loss. Vestibular diagnostic testing indicated a significant uncompensated left peripheral vestibulopathy. Imaging demonstrated no structural changes to the middle ear or labyrinth, suggesting that the auditory and vestibular losses noted on diagnostic examination were likely due to labyrinthine concussion.
CONCLUSIONS: Labyrinthine concussion may lead to reduced vestibular reflex pathway following gunshot wounds to the temporal bone. Clinical presentation is likely to vary significantly among cases.

PMID: 27092730 [PubMed - as supplied by publisher]

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Labyrinthine concussion following gunshot injury: A case report.

Labyrinthine concussion following gunshot injury: A case report.

Int J Audiol. 2016 Apr 19;:1-4

Authors: Bogle JM, Barrs D, Wester M, Davis L, Cevette MJ

Abstract
OBJECTIVE: Labyrinthine concussion due to a postauricular gunshot wound has not been well reported.
DESIGN: Retrospective chart review.
STUDY SAMPLE: We describe an otherwise healthy 22-year-old male who received a gunshot wound to the left mastoid and subsequently reported hearing loss and rotational vertigo.
RESULTS: Audiometric testing demonstrated significant inverted scoop shaped sensorineural hearing loss. Vestibular diagnostic testing indicated a significant uncompensated left peripheral vestibulopathy. Imaging demonstrated no structural changes to the middle ear or labyrinth, suggesting that the auditory and vestibular losses noted on diagnostic examination were likely due to labyrinthine concussion.
CONCLUSIONS: Labyrinthine concussion may lead to reduced vestibular reflex pathway following gunshot wounds to the temporal bone. Clinical presentation is likely to vary significantly among cases.

PMID: 27092730 [PubMed - as supplied by publisher]

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Labyrinthine concussion following gunshot injury: A case report.

Labyrinthine concussion following gunshot injury: A case report.

Int J Audiol. 2016 Apr 19;:1-4

Authors: Bogle JM, Barrs D, Wester M, Davis L, Cevette MJ

Abstract
OBJECTIVE: Labyrinthine concussion due to a postauricular gunshot wound has not been well reported.
DESIGN: Retrospective chart review.
STUDY SAMPLE: We describe an otherwise healthy 22-year-old male who received a gunshot wound to the left mastoid and subsequently reported hearing loss and rotational vertigo.
RESULTS: Audiometric testing demonstrated significant inverted scoop shaped sensorineural hearing loss. Vestibular diagnostic testing indicated a significant uncompensated left peripheral vestibulopathy. Imaging demonstrated no structural changes to the middle ear or labyrinth, suggesting that the auditory and vestibular losses noted on diagnostic examination were likely due to labyrinthine concussion.
CONCLUSIONS: Labyrinthine concussion may lead to reduced vestibular reflex pathway following gunshot wounds to the temporal bone. Clinical presentation is likely to vary significantly among cases.

PMID: 27092730 [PubMed - as supplied by publisher]

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The Genetic Homogeneity of CAPOS Syndrome: Four New Cases With the c.2452G>A (p.Glu818Lys) Mutation in the ATP1A3 Gene.

The Genetic Homogeneity of CAPOS Syndrome: Four New Cases With the c.2452G>A (p.Glu818Lys) Mutation in the ATP1A3 Gene.

Pediatr Neurol. 2016 Mar 17;

Authors: Maas RP, Schieving JH, Schouten M, Kamsteeg EJ, van de Warrenburg BP

Abstract
BACKGROUND: The clinical syndrome of cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss (CAPOS) was first described 20 years ago, but it was only recently that whole exome sequencing unveiled the causative mutation in the ATP1A3 gene. We here present four patients from the seventh and eighth family identified worldwide, provide a critical review of all cases published thus far, and speculate about the pathophysiologic processes underlying the acute neurological manifestations.
CLINICAL OBSERVATIONS: The individuals presented here experienced one to three paroxysmal, short-lasting episodes in childhood with cerebellar symptoms and signs, hypotonia, ophthalmoparesis, motor weakness, areflexia, and/or lethargy that were consistently associated with febrile illness. An underlying c.2452G>A mutation in the ATP1A3 gene was found in all four cases. Besides the persisting CAPOS features, other possibly related sequelae included dystonia, myoclonus, and emotional and behavioral changes. After initiation of acetazolamide in two patients, no further episodes occurred.
CONCLUSION: Targeted sequencing of the ATP1A3 gene is recommended in children exhibiting paroxysmal, fever-induced ataxia and in adults with a more or less stationary or slowly progressive cerebellar syndrome since childhood accompanied by mixed combinations of areflexia, pes cavus, profound visual impairment, and/or sensorineural hearing loss. Similar to some other types of episodic ataxia, acetazolamide may be considered in patients with CAPOS syndrome to prevent or attenuate bouts of ataxia, but this requires further study.

PMID: 27091223 [PubMed - as supplied by publisher]

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Hearing performance as a predictor of postural recovery in cochlear implant users.

Hearing performance as a predictor of postural recovery in cochlear implant users.

Braz J Otorhinolaryngol. 2016 Mar 31;

Authors: Greters ME, Bittar RS, Grasel SS, Oiticica J, Bento RF

Abstract
OBJECTIVE: This study aimed to evaluate if hearing performance is a predictor of postural control in cochlear implant (CI) users at least six months after surgery.
METHODS: Cross-sectional study including (CI) recipients with post-lingual deafness and controls who were divided into the following groups: nine CI users with good hearing performance (G+), five CI users with poor hearing performance (G-), and seven controls (CG). For each patient, computerized dynamic posturography (CDP) tests, a sensory organization test (SOT), and an adaptation test (ADT) were applied as dual task performance, with first test (FT) and re-test (RT) on the same day, including a 40-60min interval between them to evaluate the short-term learning ability on postural recovery strategies. The results of the groups were compared.
RESULTS: Comparing the dual task performance on CDP and the weighted average between all test conditions, the G+ group showed better performance on RT in SOT4, SOT5, SOT6, and CS, which was not observed for G- and CG. The G- group had significantly lower levels of short-term learning ability than the other two groups in SOT5 (p=0.021), SOT6 (p=0.025), and CS (p=0.031).
CONCLUSION: The CI users with good hearing performance had a higher index of postural recovery when compared to CI users with poor hearing performance.

PMID: 27090567 [PubMed - as supplied by publisher]

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Attenuation of progressive hearing loss in DBA/2J mice by reagents that affect epigenetic modifications is associated with up-regulation of the zinc importer Zip4.

Related Articles

Attenuation of progressive hearing loss in DBA/2J mice by reagents that affect epigenetic modifications is associated with up-regulation of the zinc importer Zip4.

PLoS One. 2015;10(4):e0124301

Authors: Mutai H, Miya F, Fujii M, Tsunoda T, Matsunaga T

Abstract
Various factors that are important for proper hearing have been identified, including serum levels of zinc. Here we investigated whether epigenetic regulatory pathways, which can be modified by environmental factors, could modulate hearing. RT-PCR detected expression of genes encoding DNA methyltransferase and histone deacetylase (Hdac) in the postnatal as well as adult mouse auditory epithelium. DBA/2J mice, which are a model for progressive hearing loss, were injected subcutaneously with one or a combination of the following reagents: <smallcaps>L</smallcaps>-methionine as a methyl donor, valproic acid as a pan-Hdac inhibitor, and folic acid and vitamin B12 as putative factors involved in age-related hearing loss. The mice were treated from ages 4 to 12 weeks (N ≥ 5), and auditory brainstem response (ABR) thresholds were measured at 8, 16, and 32 kHz. Treatment of the mice with a combination of <smallcaps>L</smallcaps>-methionine and valproic acid (M+V) significantly reduced the increase in the ABR threshold at 32 kHz. Treatment with any of these reagents individually produced no such effect. Microarray analyses detected 299 gene probes that were significantly up- or down-regulated in the cochleae of mice treated with M+V compared with the control vehicle-treated mice. Quantitative RT-PCR confirmed significant up-regulation of a zinc importer gene, Zip4, in the cochleae of mice treated with M+V. Immunohistochemistry demonstrated an intense Zip4 signal in cochlear tissues such as the lateral wall, organ of Corti, and spiral ganglion. Finally, mice treated with the Zip4 inducer (-)-epigallocatechin-3-O-gallate showed a significant reduction in the increase of the ABR threshold at 32 kHz and up-regulation of Zip4 expression in the cochlea. This study suggests that epigenetic regulatory pathways can modify auditory function and that zinc intake in the cochlea via Zip4 mediates maintenance of mammalian hearing.

PMID: 25875282 [PubMed - indexed for MEDLINE]

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Hearing performance as a predictor of postural recovery in cochlear implant users.

Hearing performance as a predictor of postural recovery in cochlear implant users.

Braz J Otorhinolaryngol. 2016 Mar 31;

Authors: Greters ME, Bittar RS, Grasel SS, Oiticica J, Bento RF

Abstract
OBJECTIVE: This study aimed to evaluate if hearing performance is a predictor of postural control in cochlear implant (CI) users at least six months after surgery.
METHODS: Cross-sectional study including (CI) recipients with post-lingual deafness and controls who were divided into the following groups: nine CI users with good hearing performance (G+), five CI users with poor hearing performance (G-), and seven controls (CG). For each patient, computerized dynamic posturography (CDP) tests, a sensory organization test (SOT), and an adaptation test (ADT) were applied as dual task performance, with first test (FT) and re-test (RT) on the same day, including a 40-60min interval between them to evaluate the short-term learning ability on postural recovery strategies. The results of the groups were compared.
RESULTS: Comparing the dual task performance on CDP and the weighted average between all test conditions, the G+ group showed better performance on RT in SOT4, SOT5, SOT6, and CS, which was not observed for G- and CG. The G- group had significantly lower levels of short-term learning ability than the other two groups in SOT5 (p=0.021), SOT6 (p=0.025), and CS (p=0.031).
CONCLUSION: The CI users with good hearing performance had a higher index of postural recovery when compared to CI users with poor hearing performance.

PMID: 27090567 [PubMed - as supplied by publisher]

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Attenuation of progressive hearing loss in DBA/2J mice by reagents that affect epigenetic modifications is associated with up-regulation of the zinc importer Zip4.

Related Articles

Attenuation of progressive hearing loss in DBA/2J mice by reagents that affect epigenetic modifications is associated with up-regulation of the zinc importer Zip4.

PLoS One. 2015;10(4):e0124301

Authors: Mutai H, Miya F, Fujii M, Tsunoda T, Matsunaga T

Abstract
Various factors that are important for proper hearing have been identified, including serum levels of zinc. Here we investigated whether epigenetic regulatory pathways, which can be modified by environmental factors, could modulate hearing. RT-PCR detected expression of genes encoding DNA methyltransferase and histone deacetylase (Hdac) in the postnatal as well as adult mouse auditory epithelium. DBA/2J mice, which are a model for progressive hearing loss, were injected subcutaneously with one or a combination of the following reagents: <smallcaps>L</smallcaps>-methionine as a methyl donor, valproic acid as a pan-Hdac inhibitor, and folic acid and vitamin B12 as putative factors involved in age-related hearing loss. The mice were treated from ages 4 to 12 weeks (N ≥ 5), and auditory brainstem response (ABR) thresholds were measured at 8, 16, and 32 kHz. Treatment of the mice with a combination of <smallcaps>L</smallcaps>-methionine and valproic acid (M+V) significantly reduced the increase in the ABR threshold at 32 kHz. Treatment with any of these reagents individually produced no such effect. Microarray analyses detected 299 gene probes that were significantly up- or down-regulated in the cochleae of mice treated with M+V compared with the control vehicle-treated mice. Quantitative RT-PCR confirmed significant up-regulation of a zinc importer gene, Zip4, in the cochleae of mice treated with M+V. Immunohistochemistry demonstrated an intense Zip4 signal in cochlear tissues such as the lateral wall, organ of Corti, and spiral ganglion. Finally, mice treated with the Zip4 inducer (-)-epigallocatechin-3-O-gallate showed a significant reduction in the increase of the ABR threshold at 32 kHz and up-regulation of Zip4 expression in the cochlea. This study suggests that epigenetic regulatory pathways can modify auditory function and that zinc intake in the cochlea via Zip4 mediates maintenance of mammalian hearing.

PMID: 25875282 [PubMed - indexed for MEDLINE]

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