Auditory, video head impulse test and vestibular evoked myogenic potentials findings in adults with human immunodeficiency virus

OBJECTIVES : Even though there is an association between hearing loss and human immunodeficiency virus (HIV), particularly in low- and middle-income countries, further research is needed to investigate the nature of such hearing loss. Likewise, despite documented vestibular alterations in people with HIV, the true occurrence, presentation, and nature of these manifestations are yet to be established. Advances in technology for vestibular testing has allowed for objective site-of-lesion tests such as the video head impulse test (vHIT), cervical vestibular evoked myogenic potentials (cVEMPs) and ocular vestibular evoked myogenic potential (oVEMPs). The current study aimed to compare and describe auditory, vHIT, cVEMPs and oVEMPs findings in adults with and without HIV. METHODS : The current study included an HIV positive group (n = 30) and an HIV negative group (n = 30) who underwent an auditory assessment (tympanometry and pure tone audiometry) and objective vestibular assessments. RESULTS : The occurrence of hearing loss was 53.3% in the HIV positive group compared to 33.3% in the HIV negative group. A higher occurrence of vestibular involvement was documented in the HIV positive group (73.3%) compared to 13.3% in the HIV negative group. CONCLUSION : Auditory assessment and objective measures of vestibular end-organ function (vHIT and VEMPs) can be useful to detect sub-clinical alterations. The equipment is mobile and can be performed in any health care setting such as infectious disease clinics for surveillance and monitoring purposes.http://www.elsevier.com/locate/anl2020-12-18hj2020Speech-Language Pathology and Audiolog

Vestibular involvement in adults with HIV/AIDS

OBJECTIVE : HIV/AIDS is responsible for widespread clinical manifestations involving the head, and neck.The prevalence and nature of vestibular involvement is still largely unknown. This study, aimed to describe and compare the occurrence and nature of vestibular involvement among a group of, adults infected with HIV compared to a control group. It also aimed to compare the vestibular function, of symptomatic and asymptomatic HIV positive adults who receive antiretroviral (ARV) therapies to,subjects not receiving ARV. METHODS : A cross-sectional study was conducted on 53 adults (29 male, 24 female, aged 23–49 years,mean = 38.5, SD = 4.4) infected with HIV, compared to a control group of 38 HIV negative adults (18,male, 20 female, aged 20–49 years, mean = 36.9, SD = 8.2). A structured interview probed the subjective,perception of vestibular symptoms. Medical records were reviewed for CD4+ cell counts and the use of, ARV medication. An otologic assessment and a comprehensive vestibular assessment (bedside,assessments, vestibular evoked myogenic potentials, ocular motor and positional tests and bithermal,caloric irrigation) were conducted. RESULTS : Vestibular involvement occurred in 79.2% of subjects with HIV in all categories of disease,progression, compared to 18.4% in those without HIV. Vestibular involvement increased from 18.9% in CDC category 1 to 30.2% in category 2. Vestibular involvement was 30.1% in category 3. There were,vestibular involvement in 35.9% of symptomatic HIV positive subjects, and 41.5% in asymptomatic, HIV positive subjects. There was no significant difference in the occurrence of vestibular involvement, in subjects receiving ARV therapies compared to those not receiving ARV therapies (p = .914; chi-square,test). The odds ratio indicates that individuals with HIV have a 16.61 times higher risk of developing,vestibular involvement during their lifetime of living with the disease and that it may occur despite,being asymptomatic. CONCLUSION : Vestibular involvement was significantly more common in subjects with HIV. Primary health care providers could screen HIV positive patients to ascertain if there are symptoms of vestibular involvement. If there are any, then they may consider further vestibular assessments and subsequent vestibular rehabilitation therapy.http://www.elsevier.com/locate/anlhb201

A cross-sectional survey and cross-sectional clinical trial to determine the prevalence and management of eye movement disorders and vestibular dysfunction in post-stroke patients in the sub-acute phase : protocol

INTRODUCTION: Visual impairment, specifically eye movement disorders and vestibular dysfunction may have a negative influence on the functional recovery in post-stroke patients. This type of sensory dysfunction may further be associated with poor functional outcome in patients' post-stroke. METHODS: In phase 1, a cross-sectional survey (n = 100) will be conducted to determine the prevalence of eye movement disorders and vestibular dysfunction in patients who sustained a stroke. A cross-sectional clinical trial (n = 60) will be conducted during phase 2 of the study to determine the effect of the combination of vestibular rehabilitation therapy (VRT) and visual scanning exercises (VSE) (experimental group) integrated with task-specific activities compared with the effect of task-specific activities as an intervention (control group) on patients who present with eye movement impairment and central vestibular dysfunction post-stroke. An audiologist will assess (a) visual acuity (static and dynamic), (b) nystagmus, (c) saccadic eye movements, (d) smooth pursuit eye movements, (e) vestibulo-ocular reflex, and (f) saccular, utricular, and vestibular nerve function. An independent physiotherapist will assess (1) cognitive function, (2) residual oculomotor visual performance, (3) visual-perceptual system, (4) functional balance, (5) gait, (6) functional ability, (7) presence of anxiety and/or depression, and (8) level of participation in physical activity. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the Ethics Committee of the Faculty of Health Sciences at the University of Pretoria (UP) (374/2015). The study will be submitted as fulfillment for the PhD degree at UP. Dissemination will include submission to peer-reviewed professional journals and presentation at congresses. Training of rehabilitation team members on the integration of VSE and VRT into task-specific activities in rehabilitation will be done if the outcome of the experimental group's functional performance is clinically and statistically significantly better than the control group on the Barthel Index. TRIAL REGISTRATION: Pan African Clinical Trials Registry (PACTR201509001223262).The principal researcher received a National Research Foundation Innovation Doctoral scholarship for 2016 and funding from the South African Society of Physiotherapy’s Research Foundation (VAN180).http://journal.frontiersin.org/journal/neurologyam2016PhysiotherapySpeech-Language Pathology and Audiolog

A cross-sectional survey and cross-sectional clinical trial to determine the prevalence and management of eye movement disorders and vestibular dysfunction in post-stroke patients in the sub-acute phase : protocol

INTRODUCTION: Visual impairment, specifically eye movement disorders and vestibular dysfunction may have a negative influence on the functional recovery in post-stroke patients. This type of sensory dysfunction may further be associated with poor functional outcome in patients' post-stroke. METHODS: In phase 1, a cross-sectional survey (n = 100) will be conducted to determine the prevalence of eye movement disorders and vestibular dysfunction in patients who sustained a stroke. A cross-sectional clinical trial (n = 60) will be conducted during phase 2 of the study to determine the effect of the combination of vestibular rehabilitation therapy (VRT) and visual scanning exercises (VSE) (experimental group) integrated with task-specific activities compared with the effect of task-specific activities as an intervention (control group) on patients who present with eye movement impairment and central vestibular dysfunction post-stroke. An audiologist will assess (a) visual acuity (static and dynamic), (b) nystagmus, (c) saccadic eye movements, (d) smooth pursuit eye movements, (e) vestibulo-ocular reflex, and (f) saccular, utricular, and vestibular nerve function. An independent physiotherapist will assess (1) cognitive function, (2) residual oculomotor visual performance, (3) visual-perceptual system, (4) functional balance, (5) gait, (6) functional ability, (7) presence of anxiety and/or depression, and (8) level of participation in physical activity. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the Ethics Committee of the Faculty of Health Sciences at the University of Pretoria (UP) (374/2015). The study will be submitted as fulfillment for the PhD degree at UP. Dissemination will include submission to peer-reviewed professional journals and presentation at congresses. Training of rehabilitation team members on the integration of VSE and VRT into task-specific activities in rehabilitation will be done if the outcome of the experimental group's functional performance is clinically and statistically significantly better than the control group on the Barthel Index. TRIAL REGISTRATION: Pan African Clinical Trials Registry (PACTR201509001223262).The principal researcher received a National Research Foundation Innovation Doctoral scholarship for 2016 and funding from the South African Society of Physiotherapy’s Research Foundation (VAN180).http://journal.frontiersin.org/journal/neurologyam2016PhysiotherapySpeech-Language Pathology and Audiolog

Auditory and otological manifestations in adults with HIV/AIDS

Objectives: This study aimed to describe the prevalence and nature of auditory and otological manifestations in adults with HIV/AIDS through clinical examinations and selfreported symptoms across stages of disease progression. Design: Descriptive, cross-sectional group design. Study Sample: Two hundred HIV positive adult patients attending the Infectious Disease Clinic of a tertiary referral hospital in Pretoria, South Africa were included through convenience sampling. Patients were interviewed, medical files were reviewed and clinical examinations, including otoscopy, tympanometry, pure tone audiometry and distortion product oto-acoustic emissions, were conducted. An age, gender, working-environment and race-matched control group were compiled and hearing loss prevalence were compared. Results: Tinnitus (26%), vertigo (25%) hearing loss (27.5%), otalgia (19%) and ear canal pruritis (38%) were prevalent self-reported symptoms. Abnormalities in otoscopy, tympanometry and otoacoustic emissions were evident in 55, 41 and 44% of patients respectively. Pure tone average (PTA) hearing loss >25 dBHL was evident in 14% of patients and 39% for hearing loss >15 dBHL (PTA). An increase in self reported vertigo, self reported hearing loss, OAE abnormalities and hearing loss (PTA>15dBHL and PTA>25dBHL) was seen with disease progression but was not statistically significant. A significant increase (p<.05) in sensorineural hearing loss was evident with disease progression. Significant differences were found between the average thresholds in the test and control group throughout the frequency spectrum. Conclusions: Auditory and otological symptoms are common in patients with HIV with a general increase of symptoms, especially sensorineural hearing loss, towards advanced stages of disease progression.Partial funding of this project : Centre for the study of AIDS, University of Pretoriahttp://www.tandf.co.uk/journals/titles/14992027.asphb201

Using an insect mushroom body circuit to encode route memory in complex natural environments

Ants, like many other animals, use visual memory to follow extended routes through complex environments, but it is unknown how their small brains implement this capability. The mushroom body neuropils have been identified as a crucial memory circuit in the insect brain, but their function has mostly been explored for simple olfactory association tasks. We show that a spiking neural model of this circuit originally developed to describe fruitfly (Drosophila melanogaster) olfactory association, can also account for the ability of desert ants (Cataglyphis velox) to rapidly learn visual routes through complex natural environments. We further demonstrate that abstracting the key computational principles of this circuit, which include one-shot learning of sparse codes, enables the theoretical storage capacity of the ant mushroom body to be estimated at hundreds of independent images

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M&gt;70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0&lt;e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects