Keck Medicine of USC research has implications for detecting and treating hearing loss
Exposure to loud noise, such as a firecracker or an ear-splitting concert, is the most common preventable cause of hearing loss. Research suggests that 12% or more of the world population is at risk for noise-induced loss of hearing.
Loud sounds can cause a loss of auditory nerve cells in the inner ear, which are responsible for sending acoustic information to the brain, resulting in hearing difficulty. However, the mechanism behind this hearing loss is not fully understood.
Now, a new study from Keck Medicine of USC links this type of inner ear nerve damage to a condition known as endolymphatic hydrops, a buildup of fluid in the inner ear, showing that these both occur at noise exposure levels people might encounter in their daily life.
Additionally, researchers found that treating the resulting fluid buildup with a readily available saline solution lessened nerve damage in the inner ear.
“This research provides clues to better understand how and when noise-induced damage to the ears occurs and suggests new ways to detect and prevent hearing loss,” said John Oghalai, MD, an otolaryngologist with Keck Medicine, chair of the USC Caruso Department of Otolaryngology – Head and Neck Surgery and lead author of the study.
A previous study by Oghalai conducted on mice exposed to blast pressure waves simulating a bomb explosion linked nerve damage with fluid buildup in the inner ear.
For this study, Oghalai and colleagues wanted to explore the effect of common loud sounds ranging from 80 to 100 decibels on the ear. After the exposure, they used an imaging technique known as an optical coherence tomography to measure the level of inner ear fluid in the cochlea, the hollow, spiral-shaped bone found in the inner ear.
Up until exposure to 95 decibels of sound, the inner ear fluid level remained normal. However, researchers discovered that after exposure to 100 decibels — which is equivalent to sounds such as a power lawn mower, chain saw or motorcycle — mice developed inner ear fluid buildup within hours. A week after this exposure, the animals were found to have lost auditory nerve cells.
However, when researchers applied hypertonic saline, a salt-based solution used to treat nasal congestions in humans, into affected ears one hour after the noise exposure, both the immediate fluid buildup and the long-term nerve damage lessened, implying that the hearing loss could be at least partially prevented.
These study results have several important implications, according to Oghalai, especially as the loss of nerve cells in the inner ear is known as “hidden hearing loss” because hearing tests are unable to detect the damage.
“First, if human ears exposed to loud noise, such as a siren or airbag deployment, can be scanned for a level of fluid buildup — and this technology is already being tested out — medical professionals may have a way of diagnosing impending nerve damage,” he said. “Secondly, if the scan discovered fluid buildup, people could be treated with hypertonic saline and possibly save their hearing.”
He also believes the study opens a new window into understanding Meniere’s disease, a disorder of the inner ear that causes vertigo, ringing in the ears (tinnitus) and hearing loss.
“Previously, inner ear fluid buildup was thought to be primarily linked to Meniere’s disease. This study indicates that people exposed to loud noises experience similar changes,” he said.
Oghalai hopes this study will lead to further research on the reasons ear fluid buildup occurs, and encourage the development of better treatments for Meniere’s disease.
Release date: 11 November 2021
Source: Keck Medicine of USC
Anticoagulant has beneficial side-effects for COVID-19 patients
Coronavirus disease (COVID-19) is a multifaceted infectious disease. While, at the start of the global pandemic, it was assumed that COVID-19 was primarily a disease of the lungs, it is now known that several functional systems in the human body are affected following infection with the pathogen SARS-CoV-2. One of these functional systems is blood clotting. COVID-19 patients have an increased risk of thromboses and embolisms, such as strokes, pulmonary or myocardial infarctions, and even deep vein thromboses. The use of drugs that inhibit blood clotting has been part of the treatment guidelines for COVID-19 since July 2020. “These complications during hospitalisation have a direct impact on the well-being of patients and increased the risk of dying from COVID-19,” reports David Pereyra from MedUni Vienna’s Department of General Surgery, who is first author of the publication. The underlying coagulopathy is still not fully understood.
COVID-19 triggers unique clotting problems
“The coagulopathy observed in COVID-19 patients is novel and differs in many respects from previously known coagulation problems,” says Alice Assinger, group leader at the Institute of Vascular Biology and Thrombosis Research at the Medical University of Vienna and last author of the publication, “COVID-19-associated coagulopathy displays characteristics that, although partially comparable with other coagulation diseases, cannot be fully explained by them.” Alice Assinger’s group therefore started to look for an explanation for this sub-condition of COVID-19 in the spring of 2020, in an early phase of the pandemic.
In a multi-centre analysis of COVID-19 patients in Vienna, Linz and Innsbruck, the group observed that COVID-19-associated coagulopathy occurs almost exclusively in patients requiring intensive care or in patients who die as a result of COVID-19. Although anticoagulant drugs improve the survival of COVID-19 patients, they show no effect on immunological processes related to blood coagulation (immunothrombosis).
Low-molecular-weight heparin curtails duration of infection
The analyses showed, however, that the period of active SARS-CoV-2 infection is curtailed in patients treated with low-molecular-weight heparin, the most commonly used anticoagulant. “In patients who receive this drug, infection time is an average of four days shorter than in patients who are not treated with low-molecular-weight heparin. We were surprised to see that low-molecular-weight heparin may have a direct effect on coronavirus and its infectivity,” said David Pereyra. Experimental data show that heparin can inhibit the ability of SARS-CoV-2 to bind to cells, thereby preventing them from being infected. Cardiovascular Research
Release date: 12 November 2021
Source: Medical University of Vienna
Study reveals common loud noises cause fluid buildup in the inner ear and suggests simple possible cure for noise-induced hearing loss
Keck Medicine of USC research has implications for detecting and treating hearing loss
Exposure to loud noise, such as a firecracker or an ear-splitting concert, is the most common preventable cause of hearing loss. Research suggests that 12% or more of the world population is at risk for noise-induced loss of hearing.
Loud sounds can cause a loss of auditory nerve cells in the inner ear, which are responsible for sending acoustic information to the brain, resulting in hearing difficulty. However, the mechanism behind this hearing loss is not fully understood.
Now, a new study from Keck Medicine of USC links this type of inner ear nerve damage to a condition known as endolymphatic hydrops, a buildup of fluid in the inner ear, showing that these both occur at noise exposure levels people might encounter in their daily life.
Additionally, researchers found that treating the resulting fluid buildup with a readily available saline solution lessened nerve damage in the inner ear.
“This research provides clues to better understand how and when noise-induced damage to the ears occurs and suggests new ways to detect and prevent hearing loss,” said John Oghalai, MD, an otolaryngologist with Keck Medicine, chair of the USC Caruso Department of Otolaryngology – Head and Neck Surgery and lead author of the study.
A previous study by Oghalai conducted on mice exposed to blast pressure waves simulating a bomb explosion linked nerve damage with fluid buildup in the inner ear.
For this study, Oghalai and colleagues wanted to explore the effect of common loud sounds ranging from 80 to 100 decibels on the ear. After the exposure, they used an imaging technique known as an optical coherence tomography to measure the level of inner ear fluid in the cochlea, the hollow, spiral-shaped bone found in the inner ear.
Up until exposure to 95 decibels of sound, the inner ear fluid level remained normal. However, researchers discovered that after exposure to 100 decibels — which is equivalent to sounds such as a power lawn mower, chain saw or motorcycle — mice developed inner ear fluid buildup within hours. A week after this exposure, the animals were found to have lost auditory nerve cells.
However, when researchers applied hypertonic saline, a salt-based solution used to treat nasal congestions in humans, into affected ears one hour after the noise exposure, both the immediate fluid buildup and the long-term nerve damage lessened, implying that the hearing loss could be at least partially prevented.
These study results have several important implications, according to Oghalai, especially as the loss of nerve cells in the inner ear is known as “hidden hearing loss” because hearing tests are unable to detect the damage.
“First, if human ears exposed to loud noise, such as a siren or airbag deployment, can be scanned for a level of fluid buildup — and this technology is already being tested out — medical professionals may have a way of diagnosing impending nerve damage,” he said. “Secondly, if the scan discovered fluid buildup, people could be treated with hypertonic saline and possibly save their hearing.”
He also believes the study opens a new window into understanding Meniere’s disease, a disorder of the inner ear that causes vertigo, ringing in the ears (tinnitus) and hearing loss.
“Previously, inner ear fluid buildup was thought to be primarily linked to Meniere’s disease. This study indicates that people exposed to loud noises experience similar changes,” he said.
Oghalai hopes this study will lead to further research on the reasons ear fluid buildup occurs, and encourage the development of better treatments for Meniere’s disease.
Release date: 11 November 2021
Source: Keck Medicine of USC
Anxiety effectively treated with exercise
The study, published in the Journal of Affective Disorders, is based on 286 patients with anxiety syndrome, recruited from primary care services in Gothenburg and the northern part of Halland County. Half of the patients had lived with anxiety for at least ten years. Their average age was 39 years, and 70 percent were women.
Through drawing of lots, participants were assigned to group exercise sessions, either moderate or strenuous, for 12 weeks. The results show that their anxiety symptoms were significantly alleviated even when the anxiety was a chronic condition, compared with a control group who received advice on physical activity according to public health recommendations.
Most individuals in the treatment groups went from a baseline level of moderate to high anxiety to a low anxiety level after the 12-week program. For those who exercised at relatively low intensity, the chance of improvement in terms of anxiety symptoms rose by a factor of 3.62. The corresponding factor for those who exercised at higher intensity was 4.88. Participants had no knowledge of the physical training or counseling people outside their own group were receiving.
Importance of strenuous exercise
Previous studies of physical exercise in depression have shown clear symptom improvements. However, a clear picture of how people with anxiety are affected by exercise has been lacking up to now. The present study is described as one of the largest to date.
Both treatment groups had 60-minute training sessions three times a week, under a physical therapist’s guidance. The sessions included both cardio (aerobic) and strength training. A warmup was followed by circle training around 12 stations for 45 minutes, and sessions ended with cooldown and stretching.
Members of the group that exercised at a moderate level were intended to reach some 60 percent of their maximum heart rate — a degree of exertion rated as light or moderate. In the group that trained more intensively, the aim was to attain 75 percent of maximum heart rate, and this degree of exertion was perceived as high.
The levels were regularly validated using the Borg scale, an established rating scale for perceived physical exertion, and confirmed with heart rate monitors.
Release date: 09 November 2021
Source: منبع: University of Gothenburg
Bedtime linked with heart health
Going to sleep between 10:00 and 11:00 pm is associated with a lower risk of developing heart disease compared to earlier or later bedtimes, according to a study published today in European Heart Journal – Digital Health, a journal of the European Society of Cardiology (ESC)
“The body has a 24-hour internal clock, called circadian rhythm, that helps regulate physical and mental functioning,” said study author Dr. David Plans of the University of Exeter, UK. “While we cannot conclude causation from our study, the results suggest that early or late bedtimes may be more likely to disrupt the body clock, with adverse consequences for cardiovascular health.”
While numerous analyses have investigated the link between sleep duration and cardiovascular disease, the relationship between sleep timing and heart disease is underexplored. This study examined the association between objectively measured, rather than self-reported, sleep onset in a large sample of adults.
The study included 88,026 individuals in the UK Biobank recruited between 2006 and 2010. The average age was 61 years (range 43 to 79 years) and 58% were women. Data on sleep onset and waking up time were collected over seven days using a wrist-worn accelerometer. Participants completed demographic, lifestyle, health and physical assessments and questionnaires. They were then followed up for a new diagnosis of cardiovascular disease, which was defined as a heart attack, heart failure, chronic ischaemic heart disease, stroke, and transient ischaemic attack.
During an average follow-up of 5.7 years, 3,172 participants (3.6%) developed cardiovascular disease. Incidence was highest in those with sleep times at midnight or later and lowest in those with sleep onset from 10:00 to 10:59 pm.
The researchers analysed the association between sleep onset and cardiovascular events after adjusting for age, sex, sleep duration, sleep irregularity (defined as varied times of going to sleep and waking up), self-reported chronotype (early bird or night owl), smoking status, body mass index, diabetes, blood pressure, blood cholesterol and socioeconomic status.
Compared to sleep onset from 10:00 to 10:59 pm, there was a 25% higher risk of cardiovascular disease with a sleep onset at midnight or later, a 12% greater risk for 11:00 to 11:59 pm, and a 24% raised risk for falling asleep before 10:00 pm. In a further analysis by sex, the association with increased cardiovascular risk was stronger in women, with only sleep onset before 10:00 pm remaining significant for men.
Release date: 09 November 2021
Source: European Society of Cardiology
Sitting more linked to increased feelings of depression, anxiety
As people adhered to stay-at-home orders or self-isolated during the early months of the COVID-19 outbreak, daily commutes turned into shuffles between the bedroom and the living room. Clicking Zoom links erased time spent walking to meeting rooms, and Netflix spilled into time otherwise dedicated to the gym.
In short, a lot of people suddenly became more sedentary during the onset of the pandemic. Recently published research found people who continued to spend a higher amount of time sitting between April and June 2020 were likely to have higher symptoms of depression. A closer investigation into this association could play a role in helping people improve their mental health.
To get a snapshot of those changes, Meyer and a team of researchers received survey responses from more than 3,000 study participants from all 50 states and the District of Colombia. Participants self-reported how much time they spent doing activities, like sitting, looking at screens and exercising, and how those behaviors compared to pre-pandemic times. Using standard clinical scales, they also indicated changes to their mental wellbeing (e.g., depression, anxiety, feeling stressed, lonely).
This paper in Frontiers in Psychiatry served as a follow up to see whether the participants’ behaviors and mental health changed over time. Participants filled out the same survey each week between April and June.
This study recommended people take breaks when sitting for long periods of time.
Release date: 08 November 2021
Source: Iowa State University
Just a game?
As the latest Call of Duty video game is released today, with Battlefield 2042 and a remastered Grand Theft Auto trilogy to follow later this month, research from City, University of London finds no evidence that violence increases after a new video game is released.
Mass media and general public often link violent video games to real-life violence, although there is limited evidence to support the link.
Debate on the topic generally intensifies after mass public shootings, with some commentators linking these violent acts to the perpetrators’ interests in violent video games.
However, others have pointed out that different factors, such as mental health issues and/or easy access to guns, are more likely explanations.
In the light of these conflicting claims, President Obama called in 2013 for more government funding for research on video games and violence.
But before governments introduce any policies restricting access to violent video games, it is important to establish whether violent video games do indeed make players behave violently in the real world.
The study, published in the Journal of Economic Behavior & Organization, focused on boys aged 8-18 years – the group most likely to play violent video games.
Release date: 05 November 2021
Source: City University London
Vibration Training for Multiple Sclerosis
Multiple sclerosis (MS) is a chronic neurological disease that affects the body’s central nervous system. It can limit a person’s mobility, impair physical and cognitive functions, and increase the risk of falling, collectively compromising quality of life.
Cognitive impairment has been particularly difficult for researchers to address, with few intervention strategies proven effective in preserving or restoring cognitive functions for people with MS.
Associate Professor Feng Yang worked with Francois Bethoux from the Cleveland Clinic Foundation and Georgia State University faculty members Pey-Shan Wen and Yichuan Zhao to study whether vibration training – an intervention used to improve physical function for people with MS – could also improve cognitive function and overall quality of life.
Vibration training requires individuals to sit or stand on a platform that vibrates at a fast pace but with a small movement for a specific amount of time.
For Yang’s study, believed to be the first of its kind, 18 adults with MS completed assessments to determine their perceived disability status, cognitive function and quality of life. Then, some of the participants attended vibration training three times a week for six weeks.
The study, published in the International Journal of MS Care, found that the vibration training improved not only physical abilities, such as increased walking speeds, but also cognitive functions, such as memory capacity and executive function.
Release date: 28 October 2021
Source: Georgia State University
Does physical activity impact risk of knee osteoarthritis?
In an analysis published in Arthritis & Rheumatology, investigators did not find any link between the amount and duration of physical activity with individuals’ risk of developing knee osteoarthritis.
The analysis included six global community-based studies including a total of 5,065 participants with and without knee osteoarthritis who were followed for five to 12 years.
“Knowing that the amount of physical activity and time spent doing it is not associated with the development of knee osteoarthritis is important evidence for both clinicians and the public who may need to consider this when prescribing physical activity for health,” said co–lead author Thomas Perry, BSc, PhD, of the University of Oxford, in the UK.
Next, it will be important to understand the role of injury and specific types of activity within this association, noted co–lead author Lucy S. Gates, PhD, of the University of Southampton, and co–senior author Maria Sanchez-Santos, of the University of Oxford.
Release date: 03 November 2021
Source: Wiley
Can Eating Alone Be Bad for Your Heart?
New study suggests that older women who eat alone have poorer nutritional knowledge and intake and a
higher prevalence of angina. As women age, their risk of cardiovascular disease (CVD) exceeds
men’s largely because of decreased levels of estrogen that regulate vascular function. As a result, much
research is focused on various risk factors. A new study suggests that eating alone may contribute to an
increased risk of heart disease in older women. Study results are published online in Menopause.
Release date: 03 November 2021
Source: The North American Menopause Society (NAMS)
Study finds the SARS-CoV-2 virus can infect the inner ear
The prevalence of auditory symptoms in Covid-19 patients is unknown, but infection of the inner ears may be responsible for hearing and balance problems.
Many Covid-19 patients have reported symptoms affecting the ears, including hearing loss and tinnitus. Dizziness and balance problems can also occur, suggesting that the SARS-CoV-2 virus may be able to infect the inner ear.
A new study from MIT and Massachusetts Eye and Ear provides evidence that the virus can indeed infect cells of the inner ear, including hair cells, which are critical for both hearing and balance. The researchers also found that the pattern of infection seen in human inner ear tissue is consistent with the symptoms seen in a study of 10 Covid-19 patients who reported a variety of ear-related symptoms.
The researchers used novel cellular models of the human inner ear that they developed, as well as hard-to-obtain adult human inner ear tissue, for their studies. The limited availability of such tissue has hindered previous studies of Covid-19 and other viruses that can cause hearing loss.
The study and results are published in the Journal of Communications Medicine.
Release date: 29 October 2021
Source: assachusetts Institute of Technology