Faculty Opinions recommendation of Brief predator sound exposure elicits behavioral and neuronal long-term sensitization in the olfactory system of an insect.

Asthma needs continuous treatment often for years. In humans, some drugs are administered via aerosol, therefore they come in contact with both respiratory and olfactory mucosa. We explored the possibility that antiasthma corticosteroid treatment could influence the olfactory function by passage through the nose. A group of mice was exposed twice daily for 42 days to fluticasone propionate aerosol and was compared with a control group. Olfactory behavior, respiratory mechanics, histology, and immunoreactivity in the olfactory system were assessed. Fluticasone-treated mice were slower in retrieving a piece of hidden food, but both groups were similarly fast when the food was visible. When a clearly detectable odor was present in the environment, all mice behaved in a similar way. Respiratory mechanics indices were similar in all mice except for the viscose resistance, which was reduced in fluticasone-treated mice. Olfactory mucosa of fluticasone-treated mice was thicker than that of controls. Slight but consistent differences in staining were present for Olfactory Marker Protein but not for other proteins. A mild impairment of olfactory function is present in mice chronically treated with fluticasone aerosol, apparently accompanied by slight modifications of the olfactory receptor cells, and suggests monitoring of olfactory function modifications in long-term steroid users.

Download Full-text

Effect of Infrasound and Low Frequency Sound Exposure at Intensities below 100 dB(SPL) on the Rota-Rod Treadmill Performance of Guinea Pigs

Journal of Low Frequency Noise Vibration and Active Control ◽

10.1177/026309238300200303 ◽

1983 ◽

Vol 2 (3) ◽

pp. 37-41 ◽

Cited By ~ 2

Author(s):

Naoki Maehara ◽

Reiko Kishi ◽

Terukazu Sadamoto ◽

Izumi Harabuchi ◽

Kohtaroh Yamamura

Keyword(s):

Guinea Pigs ◽

Motor Coordination ◽

Low Frequency ◽

Vestibular Function ◽

Moderate Intensity ◽

Endurance Time ◽

Frequency Sound ◽

Sound Exposure ◽

Preliminary Study

A preliminary study to investigate whether or not long-term exposure to very low frequency sound at a moderate intensity below 100 dB(SPL) affects the vestibular function and/or motor coordination in guinea pigs was carried out. At first, optimal conditions of Rota-Rod Treadmill performance for guinea pigs were determined. Then, 20 and 40 Hz-low frequency sound at 80–90 dB(SPL) exposure was used for 150 minutes and measurement of the endurance time on the Rota-Rod Treadmill was carried out at rotation speeds of 8 rpm or 10 rpm. At 10 rpm rotation speed, and 20 Hz, 90 dB(SPL) stimulus, the endurance time was significantly reduced at 150 minutes, compared with that of the control, whereas no significant reduction in endurance time was obtained at 85 dB(SPL).

Download Full-text

Long-term effects of estradiol replacement in the olfactory system

Experimental Neurology ◽

10.1016/j.expneurol.2012.06.001 ◽

2012 ◽

Vol 237 (1) ◽

pp. 1-7 ◽

Cited By ~ 12

Author(s):

Britto P. Nathan ◽

Michael Tonsor ◽

Robert G. Struble

Keyword(s):

Olfactory System ◽

Long Term Effects

Download Full-text

Mechanisms of high-intensity sound exposure on inhibiting hippocampal long-term potentiation: role of brain-derived neurotrophic factor

10.1101/850214 ◽

2019 ◽

Author(s):

Júnia L. de Deus ◽

Mateus R. Amorim ◽

Aline B. Ribeiro ◽

Procópio C. G. Barcellos-Filho ◽

César C. Ceballos ◽

...

Keyword(s):

Emotional Disorders ◽

Neurotrophic Factor ◽

High Intensity ◽

Hippocampal Slices ◽

Long Term Potentiation ◽

Brain Derived Neurotrophic Factor ◽

Sound Stimulation ◽

Sound Exposure ◽

Term Potentiation

AbstractExposure to humans and experimental animals to loud noises produce cognitive and emotional disorders and recent studies have shown that hippocampal neuronal function is affected by auditory stimulation or deprivation. We have found previously that in the hippocampus of rats exposed to high-intensity sound (110 dB) for one-minute the Schaffer-CA1 long-term potentiation (LTP) is strongly inhibited. Here we investigated possible mechanisms involved in this effect. We found, using c-fos expression, that exposure to 110 dB sound-activated neurons in the CA1 and CA3 hippocampal region. Using electrophysiological recordings in hippocampal slices, we found that both GABAergic and glutamatergic neurotransmission were unaffected by high-intensity sound stimulation. However, hippocampal brain-derived neurotrophic factor (BDNF), which is involved in promoting hippocampal synaptic plasticity, presented decreased levels in sound-stimulated animals. Perfusion of slices with BDNF revert the inhibition of LTP after a single sound stimulus in comparison to sham-stimulated rats. Furthermore, the perfusion with LM 22A4, a TrkB receptor agonist also rescued LTP from sound-stimulated animals. Our results strongly suggest that the exposure to high-intensity sound inhibits the BDNF production in the hippocampus, which could be a possible mechanism of the inhibition of LTP by high-intensity sound exposure.

Download Full-text

Behavioral Response Study on Seismic Airgun and Vessel Exposures in Narwhals

Frontiers in Marine Science ◽

10.3389/fmars.2021.658173 ◽

2021 ◽

Vol 8 ◽

Author(s):

Mads Peter Heide-Jørgensen ◽

Susanna B. Blackwell ◽

Outi M. Tervo ◽

Adeline L. Samson ◽

Eva Garde ◽

...

Keyword(s):

Noise Exposure ◽

Anthropogenic Activities ◽

Travel Speed ◽

The Arctic ◽

Line Of Sight ◽

Long Term Effects ◽

Sound Exposure ◽

Ice Coverage ◽

Exposure Levels

One of the last pristine marine soundscapes, the Arctic, is exposed to increasing anthropogenic activities due to climate-induced decrease in sea ice coverage. In this study, we combined movement and behavioral data from animal-borne tags in a controlled sound exposure study to describe the reactions of narwhals, Monodon monoceros, to airgun pulses and ship noise. Sixteen narwhals were live captured and instrumented with satellite tags and Acousonde acoustic-behavioral recorders, and 11 of them were exposed to airgun pulses and vessel sounds. The sound exposure levels (SELs) of pulses from a small airgun (3.4 L) used in 2017 and a larger one (17.0 L) used in 2018 were measured using drifting recorders. The experiment was divided into trials with airgun and ship-noise exposure, intertrials with only ship-noise, and pre- and postexposure periods. Both trials and intertrials lasted ∼4 h on average per individual. Depending on the location of the whales, the number of separate exposures ranged between one and eight trials or intertrials. Received pulse SELs dropped below 130 dB re 1 μPa2 s by 2.5 km for the small airgun and 4–9 km for the larger airgun, and background noise levels were reached at distances of ∼3 and 8–10.5 km, respectively, for the small and big airguns. Avoidance reactions of the whales could be detected at distances >5 km in 2017 and >11 km in 2018 when in line of sight of the seismic vessel. Meanwhile, a ∼30% increase in horizontal travel speed could be detected up to 2 h before the seismic vessel was in line of sight. Applying line of sight as the criterion for exposure thus excludes some potential pre-response effects, and our estimates of effects must therefore be considered conservative. The whales reacted by changing their swimming speed and direction at distances between 5 and 24 km depending on topographical surroundings where the exposure occurred. The propensity of the whales to move towards the shore increased with increasing exposure (i.e., shorter distance to vessels) and was highest with the large airgun used in 2018, where the whales moved towards the shore at distances of 10–15 km. No long-term effects of the response study could be detected.

Download Full-text

Increased hippocampal GABAergic inhibition after long-term high-intensity sound exposure

PLoS ONE ◽

10.1371/journal.pone.0210451 ◽

2019 ◽

Vol 14 (5) ◽

pp. e0210451 ◽

Cited By ~ 2

Author(s):

Alexandra O. S. Cunha ◽

Junia L. de Deus ◽

Cesar C. Ceballos ◽

Ricardo M. Leão

Keyword(s):

High Intensity ◽

Gabaergic Inhibition ◽

Sound Exposure

Download Full-text

Noise Disturbance and Potential Hearing Loss due to Exposure of Dental Equipment in Flemish Dentists

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18115617 ◽

2021 ◽

Vol 18 (11) ◽

pp. 5617

Author(s):

Michael Dierickx ◽

Suzanne Verschraegen ◽

Els Wierinck ◽

Guy Willems ◽

Astrid van Wieringen

Keyword(s):

Hearing Loss ◽

Pure Tone Audiometry ◽

General Information ◽

Sound Exposure ◽

Dental Equipment ◽

Custom Made ◽

Noise Test ◽

Years Of Service ◽

And Gender

Long-term exposure to occupational noise is often associated with noise-induced hearing loss (NIHL) among dentists. This study aims to investigate potential hearing loss (HL) and self-reported annoyance as a result of exposure to noise produced by contemporary dental equipment. Methods: Three cohorts participated: 53 dentists with more than 5 years of service, 47 dentists with at most 5 years of service, and 53 pharmacists as controls, age and gender-matched to the first group. After the exclusion of one person, the hearing of 304 ears was screened with the Flemish version of the digit triplet in noise test (DTT). If screening failed, otoscopy and pure tone audiometry (PTA) were performed for both ears. Furthermore, general information, knowledge, exposure, annoyance, general health, and preventive measures were assessed with a custom-made questionnaire. Results: NIHL did not occur significantly more often with dentists than with controls. However, dentists revealed a significantly higher annoyance (related to the noise from their equipment) and reported more complaints than the pharmacists. All three groups indicated lack of knowledge on hearing care. Conclusions: While noise levels in contemporary dentistry are not harmful and do not induce NIHL, the sounds emitted by the devices are disturbing and affect mental health. This study calls for increased awareness of the consequences of sound exposure and stresses the need to monitor and protect the hearing of dentists regularly.

Download Full-text

Confirmed central olfactory system lesions on brain MRI in COVID-19 patients with anosmia: a case-series

10.1101/2020.07.08.20148692 ◽

2020 ◽

Author(s):

Yannick Girardeau ◽

Yoan GALLOIS ◽

Guillaume DE BONNECAZE ◽

Bernard ESCUDE ◽

Clarisse LAFONT ◽

...

Keyword(s):

Orbitofrontal Cortex ◽

Olfactory System ◽

Brain Mri ◽

Case Series ◽

Olfactory Bulbs ◽

Olfactory Test ◽

High Resolution Images ◽

Smell Disorders ◽

The Impact

Objective: Anosmia has been listed as a key-symptom associated with the COVID-19 infection. Because it often occurs without any sign of rhinitis, lesions of the central olfactory system have been suspected. To date, however, there is no evidence that anosmia caused by SARS-CoV2 could be the result of brain damage. Methods: We conducted a case-series on 10 consecutive COVID-19 patients who reported anosmia. Each patient prospectively underwent a validated olfactory test (Sniffin Sticks test) and a brain MRI. Results: Hypersignal intensity lesions of the central olfactory system were found in 3 subjects on 3D T2 FLAIR and 2D T2 High Resolution images with a lesion involving the olfactory bulbs and/or the orbitofrontal cortex. These 3 subjects showed a severe and persistent loss of smell on the olfactory test. Mucosal hyperplasia of the upper nasal cavities was found in two other subjects with significant smell disorders. There was no MRI anomaly in two subjects with good smell restoration. Conclusions: Anomalies of the central olfactory system could be responsible for anosmia in patients with COVID-19 infection. Further studies are needed to assess the impact on long-term functional prognosis of these lesions.

Download Full-text