Read by QxMD icon Read


Chun Wai Yip, Michael Strupp
The Dizziness Handicap Inventory (DHI) is believed to quantitate the handicap related to the presence or severity of underlying vestibular dysfunction. However, patients with chronic vestibular diseases may manifest various degrees of behavioural and physiological adaptation resulting in variances of the DHI. Our primary study objective is to evaluate the correlation between the DHI and measurable vestibular parameters. Secondarily, we compared DHI among different vestibular disorders (central, peripheral and functional), and different types of anatomic deficits (semicircular canal vs otolithic)...
March 20, 2018: Journal of Neurology
Parthena Soupiadou, Francisco Branoner, Hans Straka
Vestibulo-ocular reflexes (VOR) are mediated by three-neuronal brainstem pathways that transform semicircular canal and otolith sensory signals into motor commands for the contraction of spatially specific sets of eye muscles. The vestibular excitation and inhibition of extraocular motoneurons underlying this reflex is reciprocally organized and allows coordinated activation of particular eye muscles and concurrent relaxation of their antagonistic counterparts. Here, we demonstrate in isolated preparations of Xenopus laevis tadpoles that the discharge modulation of superior oblique motoneurons during cyclic head motion derives from an alternating excitation and inhibition...
March 19, 2018: Journal of Neurology
N Fukuda, H Kurogi, D Ambe, S Chow, T Yamamoto, K Yokouchi, A Shinoda, Y Masuda, M Sekino, K Saitoh, M Masujima, T Watanabe, N Mochioka, H Kuwada
This study clarifies the location, size and age at the onset of metamorphosis in Japanese eels Anguilla japonica through oceanic surveys, rearing experiments and analyses of the morphology and otoliths of leptocephali and glass eels. Twenty-eight metamorphosing leptocephali were collected in the mesoscale eddy region to the east of Taiwan during research expeditions in 2004. Rearing experiments showed that the total length (LT ) of leptocephali decreased by an average of 12·5% during metamorphosis and 13·9% during the 2-12 h after death...
March 14, 2018: Journal of Fish Biology
Kourosh Parham, George A Kuchel, Janet E McElhaney, Laura Haynes
OBJECTIVE: Low vitamin D levels have been associated with and could play a role in the pathogenesis of idiopathic benign paroxysmal positional vertigo (iBPPV). Since otoconia degeneration contributes to iBPPV and a lack of vitamin D may impact otoconia structure and integrity, we proposed a negative association between vitamin D levels and levels of a proposed circulatory biomarker for otolithic degeneration, otolin-1. STUDY DESIGN: Cross-sectional clinical study...
April 2018: Otology & Neurotology
L M Cavole, L G Cardoso, M S Almeida, M Haimovici
Uncertainty regarding the age determination of the Brazilian codling Urophycis brasiliensis has hampered its stock assessment. Transverse sections of otoliths displayed up to seven (in males) and 12 (in females) alternate opaque and translucent bands that could not be conclusively validated as annuli, resulting in unrealistically high ages of first maturity (A50 ) (A50male  = 4·5 years and A50female  = 6 years). Therefore, growth was described by the von Bertalanffy (VB) model using an alternative approach that combined microstructure data (daily growth increments) and a fixed asymptotic total length (L∞ )...
March 12, 2018: Journal of Fish Biology
Jens C Hegg, Jonathan Middleton, Ben Luca Robertson, Brian P Kennedy
The migration of Pacific salmon is an important part of functioning freshwater ecosystems, but as populations have decreased and ecological conditions have changed, so have migration patterns. Understanding how the environment, and human impacts, change salmon migration behavior requires observing migration at small temporal and spatial scales across large geographic areas. Studying these detailed fish movements is particularly important for one threatened population of Chinook salmon in the Snake River of Idaho whose juvenile behavior may be rapidly evolving in response to dams and anthropogenic impacts...
February 2018: Heliyon
Richard Boyle, Reza Ehsanian, Alireza Mofrad, Yekaterina Popova, Joseph Varelas
The utricle provides the vestibular reflex pathways with the sensory codes of inertial acceleration of self motion and head orientation with respect to gravity to control balance and equilibrium. Here we present an anatomical description of this structure in the adult oyster toadfish, and establish a morphological basis for interpretation of subsequent functional studies. Light, scanning and transmission electron microscopy techniques were applied to visualize the sensory epithelium at varying levels of detail, its neural innervation and its synaptic organization...
March 10, 2018: Journal of Comparative Neurology
Henri Traboulsi, Michael Teixido
Introduction/Objective: Multiple canal BPPV can be a diagnostic challenge to the clinician. This is due in part to the complex anatomy of the labyrinth but also to complex and often simultaneous ocular responses that result from stimulation of multiple canals during traditional diagnostic testing. Our objective was to analyze the Dix-Hallpike maneuver used in the diagnosis of BPPV to look for patterns of simultaneous canal response and to develop a diagnostic maneuver that will allow separation of canal responses in multiple canal BPPV...
September 2017: World Journal of Otorhinolaryngology—Head and Neck Surgery
P S P Vandenbussche, G Spennato, P M Pierson
Human impact on the environment is of widespread concern. The majority of anthropogenic impacts are centred on coastal ecosystems, so surveying them is an important step in the protection of the marine environment. We have tested Oblada melanura (L. 1758) otoliths' fluctuating asymmetry as a bioindicator in a Mediterranean coastal zone. The French Riviera is characterised by a summer population increase leading in particular to more yachting, and seasonal climatic changes with reduced, more concentrated waterway flows and storm events causing soil erosion...
February 22, 2018: Marine Environmental Research
Shiro Itoi, Yukako Mochizuki, Minori Tanaka, Hikaru Oyama, Tadasuke Tsunashima, Riko Yamada, Hirotoshi Shishido, Yasuji Masuda, Shizuko Nakai, Noriyuki Takai, Hideto Fukushima, Koko Abe, Takahito Kojima, Haruo Sugita
Current literature states that family Scombropidae consists of a single genus Scombrops comprising three species worldwide, with two of them, Scombrops boops and Scombrops gilberti, distributed in the waters around the Japanese Archipelago. Although these two scombropids are commercially important species, little is known about the ecology of these fishes. It is difficult to discriminate between these two species based on external characteristics because of their morphological similarity. Here, we report two different morphotypes characterized by the relative growth between the otolith size and the standard length (SL) of the scombropid specimens caught in southern waters off Kyushu Island, Japan, and show the genetic relationship between the morphotypes by means of phylogenetic analyses using complete DNA sequences of the cytochrome b gene...
February 28, 2018: Mitochondrial DNA. Part A. DNA Mapping, Sequencing, and Analysis
Sung-Hee Kim, Ji-Soo Kim
Objective: Internal representation of gravity can be quantified by measuring the subjective visual vertical (SVV). Modulation of verticality perception during head tilts may be perturbed in vestibular disorders causing SVV tilts in the upright head position. This study aimed to determine the influence of head tilts on the estimation of SVV in acute vestibular disorders. Methods: We measured the SVV in 37 patients with acute vestibular symptoms due to unilateral vestibular neuritis (VN) ( n  = 28) and lateral medullary infarction (LMI) ( n  = 9)...
2018: Frontiers in Neurology
Xiao Han, Haibo Xie, Yadong Wang, Chengtian Zhao
Radial spokes are structurally conserved, macromolecular complexes that are essential for the motility of 9 + 2 motile cilia. In Chlamydomonas species, mutations in radial spoke proteins result in ciliary motility defects. However, little is known about the function of radial spoke proteins during embryonic development. Here, we investigated the role of a novel radial spoke protein, leucine-rich repeat containing protein 23 (Lrrc23), during zebrafish embryonic development. Mutations in lrrc23 resulted in a selective otolith formation defect during early ear development...
February 22, 2018: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
Amanda I Rodriguez, Megan L A Thomas, Denis Fitzpatrick, Kristen L Janky
OBJECTIVES: Vestibular evoked myogenic potential (VEMP) testing is increasingly utilized in pediatric vestibular evaluations due to its diagnostic capability to identify otolith dysfunction and feasibility of testing. However, there is evidence demonstrating that the high-intensity stimulation level required to elicit a reliable VEMP response causes acoustic trauma in adults. Despite utility of VEMP testing in children, similar findings are unknown. It is hypothesized that increased sound exposure may exist in children because differences in ear-canal volume (ECV) compared with adults, and the effect of stimulus parameters (e...
March 2018: Ear and Hearing
Fred H Previc
INTRODUCTION: A theory is presented to explain the major findings regarding motion sickness and to synthetize current theories concerning its etiology. The theory proposes that an imbalance in the output of the two major organs of the labyrinth-favoring the semicircular canals over the otolith organs-is responsible for most instances of motion sickness as experienced in terrestrial and microgravity environments. METHODS: Strengths and limitations of current theories are first outlined before the different roles of the canals and otoliths in the genesis of motion sickness symptoms are described...
February 1, 2018: Aerospace Medicine and Human Performance
Tanja Schulz-Mirbach, Margie Olbinado, Alexander Rack, Alberto Mittone, Alberto Bravin, Roland R Melzer, Friedrich Ladich, Martin Heß
Regarding the basics of ear structure-function relationships in fish, the actual motion of the solid otolith relative to the underlying sensory epithelium has rarely been investigated. Otolith motion has been characterized based on a few experimental studies and on approaches using mathematical modeling, which have yielded partially conflicting results. Those studies either predicted a simple back-and-forth motion of the otolith or a shape-dependent, more complex motion. Our study was designed to develop and test a new set-up to generate experimental data on fish otolith motion in-situ...
February 15, 2018: Scientific Reports
V Visconti, E D L Trip, M H Griffiths, K D Clements
The present study describes the age and growth of the leatherjacket Meuschenia scaber, a common Australasian monacanthid and valued by-catch of the inshore bottom trawl fishery in New Zealand. Age was determined from the sagittal otoliths of 651 individuals collected between July 2014 and March 2016 in the Hauraki Gulf of New Zealand. Otolith sections revealed alternating opaque and translucent zones and edge-type analysis demonstrated that these are deposited annually. Meuschenia scaber displayed rapid initial growth, with both males and females reaching maturity in 1-2 years and 50% of both sexes matured at 1·5 years...
February 2018: Journal of Fish Biology
Joyce J L Ong, Adam N Rountrey, Bryan A Black, Hoang Minh Nguyen, Peter G Coulson, Stephen J Newman, Corey B Wakefield, Jessica J Meeuwig, Mark G Meekan
Entrainment of growth patterns of multiple species to single climatic drivers can lower ecosystem resilience and increase the risk of species extinction during stressful climatic events. However, predictions of the effects of climate change on the productivity and dynamics of marine fishes are hampered by a lack of historical data on growth patterns. We use otolith biochronologies to show that the strength of a boundary current, modulated by the El Niño-Southern Oscillation, accounted for almost half of the shared variance in annual growth patterns of five of six species of tropical and temperate marine fishes across 23° of latitude (3000 km) in Western Australia...
February 7, 2018: Global Change Biology
Maitreyi A Nair, Ajitkumar P Mulavara, Jacob J Bloomberg, Haleh Sangi-Haghpeykar, Helen S Cohen
People with benign paroxysmal positional vertigo (BPPV) probably have otoconial particles displaced from the utricle into the posterior semicircular canal. This unilateral change in the inertial load distributions of the labyrinth may result in visual dependence and may affect balance control. The goal of this study was to explore the interaction between visual dependence and balance control. We compared 23 healthy controls to 17 people with unilateral BPPV on the Clinical Test of Sensory Interaction and Balance on compliant foam with feet together, the Rod-and-Frame Test and a Mental Rotation Test...
2018: Journal of Vestibular Research: Equilibrium & Orientation
Helge Rask-Andersen, Nadine Schart-Morén, Karin Strömbäck, Fred Linthicum, Hao Li
The anatomy of the vestibular organs together with considerations of the middle and inner ear anatomy relevant to stapes surgery is discussed. An archival collection of macerated and freshly frozen human temporal bones underwent micro-computed tomography (CT) with subsequent volume-rendering. Three-dimensional (3D) reconstructions and the topographic anatomy of the oval window were considered. Micro-CT and 3D rendering revealed the relationship between the otolith organs and the oval window. Anatomic variations were extensive and included the distance between the footplate and the reconstructed macula margins...
January 31, 2018: Otolaryngologic Clinics of North America
Melissa Fiscaletti, Andrew Biggin, Bruce Bennetts, Karen Wong, Julie Briody, Verity Pacey, Catherine Birman, Craig F Munns
Osteogenesis imperfecta (OI) is a connective tissue disorder characterized by low bone density and recurrent fractures with a wide genotypic and phenotypic spectrum. Common features include short stature, opalescent teeth, blue sclerae and hearing impairment. The majority (>90%) of patients with OI have autosomal dominant variants in COL1A1/COL1A2, which lead to defects in type 1 collagen. More recently, numerous recessive variants involving other genes have also been identified. Sp7/Osx gene, is a protein coding gene that encodes a zinc finger transcription factor, osterix, which is a member of the Sp subfamily of sequence-specific DNA-binding proteins...
January 27, 2018: Bone
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"