Day: January 16, 2025

Categories : Neurodegenerative DiseasesTags :

Hearing Impairment may be a Sign of Increased Risk of Parkinson’s Disease

On By ModernMedia
Photo by JD Mason on Unsplash

There may be a link between hearing impairment and an increased risk of developing Parkinson’s according to research led by Lancaster University. This is one of the first studies to examine whether sensory impairments, such as hearing loss, might increase the risk for Parkinson’s or serve as an early warning sign.

The study is published in Parkinsonism and Related Disorders.

Researchers analysed data from the UK Biobank, a biomedical database containing data from half a million participants across the UK. They looked at data from 159,395 individuals who had previously undergone a hearing test measuring their ability to detect speech in noisy environments and had no history of Parkinson’s at the time of the assessment.

Over an average follow-up period of 14.24 years, 810 participants were subsequently diagnosed with Parkinson’s disease. The analysis revealed a 57% increased risk of Parkinson’s for every 10-decibel increase in baseline hearing impairment.

Dr Megan Readman, ESRC Post Doctoral Research Fellow from Lancaster University’s Department of Psychology, led the study.

She said: “These findings are incredibly important; first, this is one of the first studies to look at how hearing impairments may increase risk for Parkinson’s or be an early warning sign of Parkinson’s.

“Secondly, as our findings suggest, hearing loss is intricately related to Parkinson’s so it may be beneficial for auditory functioning and the management of auditory impairment to be considered at the time of diagnosis and follow-up care.”

However, Dr Readman stressed that it is not clear if the link between Parkinson’s and hearing loss is causal or if there is simply a correlation.

“We do not know whether hearing loss can cause Parkinson’s, or if there is a common underlying cause for both conditions.”

The other authors included Yang Wang and Fang Wan, Sally Linkenauger, Trevor Crawford and Christopher Plack plus Ian Fairman who has Parkinson’s and hearing impairment.

Professor Plack said: “It is increasingly clear that hearing loss is not an isolated condition but is associated with several other disorders. Understanding these links is vital if we are to provide effective patient care, improving independence and quality of life for the individuals concerned.”

By identifying factors that might contribute to its onset, such as hearing impairment, researchers hope to pave the way for new strategies in prevention and care.

Dr Readman said: “Our findings suggest hearing impairment is intricately related to Parkinson’s and underscore the potential benefits of addressing auditory function in Parkinson’s diagnosis and follow-up care.”

Professor Trevor Crawford said: “This important study is the latest discovery in a decade-long series of research on neurodegenerative disorders, conducted by our team at Lancaster University in collaboration with colleagues across the UK.”

Source: Lancaster University

Categories : Regenerative MedicineTags :

Bird flu is Mutating, but Antivirals Still Work

On By ModernMedia
Professor Luis Martinez-Sobrido, Ph.D., (left) and Staff Scientist Ahmed Mostafa Elsayed, PhD, (right) review test results for the presence of bird flu while wearing protective equipment required for biosafety level-3 laboratories.

One of the earliest strains of bird flu isolated from a human in Texas shows a unique constellation of mutations that enable it to more easily replicate in human cells and cause more severe disease in mice compared to a strain found in dairy cattle, researchers from Texas Biomedical Research Institute (Texas Biomed) report in Emerging Microbes & Infections.

The finding highlights a key concern about the H5N1 strains of bird flu currently circulating in the U.S.: the speed at which the virus can mutate when introduced to a new host.

Naturally found in wild birds and lethal in chickens, H5N1 has spread to a wide variety of mammals and began infecting dairy cows for the first time in spring 2024. As of early 2025, the outbreak had spread through herds across multiple states in the U.S. and infected dozens of people, mostly farm workers. So far, most people infected experience mild illness and eye inflammation and the virus is not spreading between people. The first H5N1 death in the U.S. was reported in January 2025 following exposure to infected chickens.

“The clock is ticking for the virus to evolve to more easily infect and potentially transmit from human to human, which would be a concern,” said Texas Biomed Professor Luis Martinez-Sobrido, PhD, whose lab specialises in influenza viruses and has been studying H5N1 since the outbreak began last year. The team has developed specialised tools and animal models to test prophylactic vaccines and therapeutic antivirals.

Human vs bovine

In the recent study, they compared H5N1 strains isolated from a human patient and from dairy cattle in Texas.

“There are nine mutations in the human strain that were not present in the bovine strain, which suggests they occurred after human infection,” Dr Martinez-Sobrido said.

In mouse studies, they found that compared to the bovine strain, the human strain replicated more efficiently, caused more severe disease and was found in much higher quantities in brain tissue. They also tested several FDA-approved antiviral medications to see if they were effective against both virus strains in cells.

“Fortunately, the mutations did not affect the susceptibility to FDA-approved antivirals,” said Staff Scientist Ahmed Mostafa Elsayed, PhD, first author of the study.

Antivirals will be a key line of defence should a pandemic occur before vaccines are widely available, Dr Martinez-Sobrido said. This is especially true since humans have no preexisting immunity against H5N1 and seasonal flu vaccines appear to offer very limited protection, according to a separate study conducted in collaboration with Aitor Nogales, PhD, at the Center for Animal Health Research in Spain.

Dr Elsayed shows the host species of the four types of influenza viruses: A, B, C and D. Avian influenza is part of the influenza A group and has infected a wide range of species. Influenza A and B are responsible for seasonal flu in humans.

Next steps and recommendations

Texas Biomed is now exploring the human H5N1 mutations individually to determine which are responsible for increased pathogenicity and virulence. The team wants to figure out what allows H5N1 to infect such a wide range of mammal species; why H5N1 causes mild disease in cows but is lethal in cats; and why infections via cows are less harmful to people than infections from chickens.

In a third paper, Dr Elsayed and collaborators analysed the history of H5N1 in dairy cattle for the journal mBio and called for a One Health approach to protect both animals and people.

“A key priority will be to eradicate bird flu from dairy cows to minimise risk of mutations and transmission to people and other species,” Dr Elsayed said. “Steps that can be taken now include thorough decontamination of milking equipment and more stringent quarantine requirements, which will help eliminate the virus more quickly in cows.”

Source: Texas Biomedical Research Institute

Categories : Exercise Neurodegenerative DiseasesTags :

Long-term Study Finds Red Meat Raises Dementia Risk

On By ModernMedia
Photo by Jose Ignacio Pompe on Unsplash

People who eat more red meat, especially processed red meat like bacon, sausage and bologna, are more likely to have a higher risk of cognitive decline and dementia when compared to those who eat very little red meat, according to a study published in the January 15, 2025, online issue of Neurology®, the medical journal of the American Academy of Neurology.

“Red meat is high in saturated fat and has been shown in previous studies to increase the risk of type 2 diabetes and heart disease, which are both linked to reduced brain health,” said study author Dong Wang, MD, ScD, of Brigham and Women’s Hospital in Boston. “Our study found processed red meat may increase the risk of cognitive decline and dementia, but the good news is that it also found that replacing it with healthier alternatives, like nuts, fish and poultry, may reduce a person’s risk.”

To examine the risk of dementia, researchers included a group of 133 771 people (65.4% female) with an average age of 49 who did not have dementia at the start of the study. They were followed up to 43 years. Of this group, 11 173 people developed dementia.

Participants completed a food diary every two to four years, listing what they ate and how often.

Researchers defined processed red meat as bacon, hot dogs, sausages, salami, bologna and other processed meat products. They defined unprocessed red meat as beef, pork, lamb and hamburger. A serving of red meat is three ounces (85gm), about the size of a deck of cards.

For processed red meat, they divided participants into three groups. The low group ate an average of fewer than 0.10 servings per day; the medium group ate between 0.10 and 0.24 servings per day; and the high group, 0.25 or more servings per day.

After adjusting for factors such as age, sex and other risk factors for cognitive decline, researchers found that participants in the high group had a 13% higher risk of developing dementia compared to those in the low group.

For unprocessed red meat, researchers compared people who ate an average of less than one half serving per day to people who ate one or more servings per day and did not find a difference in dementia risk.

To measure subjective cognitive decline, researchers looked at a different group of 43,966 participants with an average age of 78. Subjective cognitive decline is when a person reports memory and thinking problems before any decline is large enough to show up on standard tests.

The subjective cognitive decline group took surveys rating their own memory and thinking skills twice during the study.

After adjusting for factors such as age, sex and other risk factors for cognitive decline, researchers found that participants who ate an average of 0.25 servings or more per day of processed red meat had a 14% higher risk of subjective cognitive decline compared to those who ate an average of fewer than 0.10 servings per day.

They also found people who ate one or more servings of unprocessed red meat per day had a 16% higher risk of subjective cognitive decline compared to people who ate less than a half serving per day.

To measure objective cognitive function, researchers looked at a different group of 17 458 female participants with an average age of 74. Objective cognitive function is how well your brain works to remember, think and solve problems.

This group took memory and thinking tests four times during the study.

After adjusting for factors such as age, sex and other risk factors for cognitive decline, researchers found that eating higher processed red meat was associated with faster brain aging in global cognition with 1.61 years with each additional serving per day and in verbal memory with 1.69 years with each additional serving per day.

Finally, researchers found that replacing one serving per day of processed red meat with one serving per day of nuts and legumes was associated with a 19% lower risk of dementia and 1.37 fewer years of cognitive aging. Making the same substitution for fish was associated with a 28% lower risk of dementia and replacing with chicken was associated with a 16% lower risk of dementia.

“Reducing how much red meat a person eats and replacing it with other protein sources and plant-based options could be included in dietary guidelines to promote cognitive health,” said Wang. “More research is needed to assess our findings in more diverse groups.”

A limitation of the study was that it primarily looked at white health care professionals, so the results might not be the same for other race, ethnic and non-binary sex and gender populations.

Source: American Academy of Neurology

Categories : Medical Research & Technology NeurologyTags :

New Flexible ‘Tentacle’ Electrodes can Precisely Record Brain Activity

On By ModernMedia
A bundle of extremely fine electrode fibres in the brain (microscope image). (Image: Yasar TB et al. Nature Communications 2024, modified)

Researchers at ETH Zurich have developed ultra-flexible brain probes that accurately record brain activity without causing tissue damage. This technology, described in Nature Communications, opens up new avenues for the treatment of a range of neurological and neuropsychiatric disorders. 

Neurostimulators, also known as brain pacemakers, send electrical impulses to specific areas of the brain via special electrodes. It is estimated that some 200 000 people worldwide are now benefiting from this technology, including those who suffer from Parkinson’s disease or from pathological muscle spasms. According to Mehmet Fatih Yanik, Professor of Neurotechnology at ETH Zurich, further research will greatly expand the potential applications: instead of using them exclusively to stimulate the brain, the electrodes can also be used to precisely record brain activity and analyse it for anomalies associated with neurological or psychiatric disorders. In a second step, it would be conceivable in future to treat these anomalies and disorders using electrical impulses.

To this end, Yanik and his team have now developed a new type of electrode that enables more detailed and more precise recordings of brain activity over an extended period of time. These electrodes are made of bundles of extremely fine and flexible fibres of electrically conductive gold encapsulated in a polymer. Thanks to a process developed by the ETH Zurich researchers, these bundles can be inserted into the brain very slowly, which is why they do not cause any detectable damage to brain tissue.

This sets the new electrodes apart from rival technologies. Of these, perhaps the best known in the public sphere is the one from Neuralink, an Elon Musk company. In all such systems, including Neuralink’s, the electrodes are considerably wider. “The wider the probe, even if it is flexible, the greater the risk of damage to brain tissue,” Yanik explains. “Our electrodes are so fine that they can be threaded past the long processes that extend from the nerve cells in the brain. They are only around as thick as the nerve-cell processes themselves.”

The tentacle electrodes (right) shown alongside three current technologies using thicker electrodes or an electrode mesh. (Yasar TB et al. Nature Communications 2024, modified)

The research team tested the new electrodes on the brains of rats using four bundles, each made up of 64 fibres. In principle, as Yanik explains, up to several hundred electrode fibres could be used to investigate the activity of an even greater number of brain cells. In the study, the electrodes were connected to a small recording device attached to the head of each rat, thereby enabling them to move freely.

No influence on brain activity

In the experiments, the research team was able to confirm that the probes are biocompatible and that they do not influence brain function. Because the electrodes are very close to the nerve cells, the signal quality is very good compared to other methods.

At the same time, the probes are suitable for long-term monitoring activities, with researchers recording signals from the same cells in the brains of animals for the entire duration of a ten-month experiment. Examinations showed that no brain-tissue damage occurred during this time. A further advantage is that the bundles can branch out in different directions, meaning that they can reach multiple brain areas.

Human testing to begin soon

In the study, the researcher used the new electrodes to track and analyse nerve-cell activity in various areas of the brains of rats over a period of several months. They were able to determine that nerve cells in different regions were “co-activated”. Scientists believe that this large-scale, synchronous interaction of brain cells plays a key role in the processing of complex information and memory formation. “The technology is of high interest for basic research that investigates these functions and their impairments in neurological and psychiatric disorders,” Yanik explains.

The group has teamed up with fellow researchers at the University College London in order to test diagnostic use of the new electrodes in the human brain. Specifically, the project involves epilepsy sufferers who do not respond to drug therapy. In such cases, neurosurgeons may remove a small part of the brain where the seizures originate. The idea is to use the group’s method to precisely localise the affected area of the brain prior to tissue removal.

Brain-machine interfaces

There are also plans to use the new electrodes to stimulate brain cells in humans. “This could aid the development of more effective therapies for people with neurological and psychiatric disorders”, says Yanik. In disorders such as depression, schizophrenia or OCD, there is often impairments in specific regions of the brain, which leads to problems in evaluation of information and decision making. Using the new electrodes, it might be possible to detect the pathological signals generated by the neural networks in the brain in advance, and then stimulate the brain in a way that would alleviate such disorders. Yanik also thinks that this technology may give rise to brain-machine interfaces for people with brain injuries. In such cases, the electrodes might be used to read their intentions and thereby, for example, to control prosthetics or a voice-output system.

Source: ETH Zurich

Categories : Skeletal SystemTags :

Discovery of New Skeletal Tissue Holds Promise for Regenerative Medicine

On By ModernMedia
“Lipocartilage” is a type of supportive skeletal tissue, that consists of densely packed, bubble-like cells containing fat. This image shows a scan of mouse ear lipocartilage stained with a green fluorescent dye. Charlie Dunlop School of Biological Sciences

An international research team led by the University of California, Irvine has discovered a new type of skeletal tissue that offers great potential for advancing regenerative medicine and tissue engineering.

Most cartilage relies on an external extracellular matrix for strength, but “lipocartilage,” which is found in the ears, nose and throat of mammals, is uniquely packed with fat-filled cells called “lipochondrocytes” that provide super-stable internal support, enabling the tissue to remain soft and springy – similar to bubbled packaging material.

The study, published in the journal Science, describes how lipocartilage cells create and maintain their own lipid reservoirs, remaining constant in size. Unlike ordinary adipocyte fat cells, lipochondrocytes never shrink or expand in response to food availability.

“Lipocartilage’s resilience and stability provide a compliant, elastic quality that’s perfect for flexible body parts such as earlobes or the tip of the nose, opening exciting possibilities in regenerative medicine and tissue engineering, particularly for facial defects or injuries,” said corresponding author Maksim Plikus, UC Irvine professor of developmental and cell biology. “Currently, cartilage reconstruction often requires harvesting tissue from the patient’s rib – a painful and invasive procedure. In the future, patient-specific lipochondrocytes could be derived from stem cells, purified and used to manufacture living cartilage tailored to individual needs. With the help of 3D printing, these engineered tissues could be shaped to fit precisely, offering new solutions for treating birth defects, trauma and various cartilage diseases.”

Dr Franz Leydig first recognised lipochondrocytes in 1854, when he noted the presence of fat droplets in the cartilage of rat ears, a finding that was largely forgotten until now. With modern biochemical tools and advanced imaging methods, UC Irvine researchers comprehensively characterised lipocartilage’s molecular biology, metabolism and structural role in skeletal tissues.

They also uncovered the genetic process that suppresses the activity of enzymes that break down fats and reduce the absorption of new fat molecules, effectively locking lipochondrocytes’s lipid reserves in place. When stripped of its lipids, the lipocartilage becomes stiff and brittle, highlighting the importance of its fat-filled cells in maintaining the tissue’s combination of durability and flexibility. In addition, the team noted that in some mammals, such as bats, lipochondrocytes assemble into intricate shapes, like parallel ridges in their oversized ears, which may enhance hearing acuity by modulating sound waves.

“The discovery of the unique lipid biology of lipocartilage challenges long-standing assumptions in biomechanics and opens doors to countless research opportunities,” said the study’s lead author, Raul Ramos, a postdoctoral researcher in the Plikus laboratory for developmental and regenerative biology. “Future directions include gaining an understanding of how lipochondrocytes maintain their stability over time and the molecular programs that govern their form and function, as well as insights into the mechanisms of cellular aging. Our findings underscore the versatility of lipids beyond metabolism and suggest new ways to harness their properties in tissue engineering and medicine.”

Source: University of California – Irvine