Wednesday, May 14, 2025

 

Tiny device promises new tech with a human touch




RMIT University
Researcher inspects the team's neuromorphic vision device 

image: 

RMIT PhD scholar and study first author Thiha Aung inspects the team's neuromorphic vision device.

view more 

Credit: Will Wright, RMIT University




Engineers at RMIT University have invented a small ‘neuromorphic’ device that detects hand movement, stores memories and processes information like a human brain, without the need for an external computer.

Team leader Professor Sumeet Walia said the innovation marked a step towards enabling instant visual processing in autonomous vehicles, advanced robotics and other next-generation applications for improved human interaction.

“Neuromorphic vision systems are designed to use similar analogue processing to our brains, which can greatly reduce the amount of energy needed to perform complex visual tasks compared with digital technologies used today,” said Walia, Director of the RMIT Centre for Opto-electronic Materials and Sensors (COMAS).

The work brings together neuromorphic materials and advanced signal processing led by Professor Akram Al-Hourani, who is Deputy Director of COMAS.

The device contains a metal compound known as molybdenum disulfide, or MoS2.

In their latest study, the team showed how atomic-scale defects in this compound can be harnessed to capture light and process it as electrical signals, like how neurons work in our brain.

“This proof-of-concept device mimics the human eye’s ability to capture light and the brain’s ability to process that visual information, enabling it to sense a change in the environment instantly and make memories without the need for using huge amounts of data and energy,” Walia said.

“Current digital systems, by contrast, are very power hungry and unable to keep up as data volume and complexity increases, which limits their ability to make ‘true’ real-time decisions.”

The research is published in Advanced Materials Technologies. Walia and Al-Hourani are corresponding authors and Mr Thiha Aung, a PhD scholar at RMIT, is first author.

RMIT has filed a provisional patent for the work.

Seeing the future in the wave of a hand

During experiments, the device detected changes in a waving hand’s movement, without the need to capture the events frame by frame – this is known as edge detection, which requires significantly less data processing and power.  

Once the changes were detected, the device stored these events as memories like a brain.

The researchers conducted experiments in the spectrum visible to the human eye, which built upon the team’s previous neuromorphic research in the ultraviolet domain.

“We demonstrated that atomically thin molybdenum disulfide can accurately replicate the leaky integrate-and-fire (LIF) neuron behaviour, a fundamental building block of spiking neural networks,” Thiha said.

The past UV work only involved the detection, memory making and processing of still images. In both the visible-spectrum and UV devices, memories could be reset so that devices were ready to perform the next task.

Potential applications

The team’s innovation could one day improve response times of automated vehicles and advanced robotic systems to visual information, which could be crucial particularly in dangerous and unpredictable environments.

“Neuromorphic vision in these applications, which is still many years away, could detect changes in a scene almost instantly, without the need to process lots of data, enabling a much faster response that could save lives,” Walia said.

“For robots working closely with humans in manufacturing or as a personal assistant, neuromorphic technology could enable more natural interactions by recognising and reacting to human behaviour with minimal delay,” Al-Hourani said.

Next steps

The team is now scaling up the proof-of-concept single-pixel device to a larger pixel array of MoS2-based devices.

The Australian Research Council has recently funded the team with a Linkage Infrastructure, Equipment and Facilities (LIEF) grant to enable this scaling up of their neuromorphic devices.

“While our system mimics certain aspects of the brain’s neural processing, particularly in vision, it's still a simplified model,” Walia said.

“We will optimise the devices to perform specific real-world applications with more complex vision tasks, and further reduce power consumption.”

The team plans to develop hybrid systems that integrate their analogue technology with conventional digital electronics.

“We see our work as complementary to traditional computing, rather than a replacement,” Walia said.

“Conventional systems excel at many tasks, while our neuromorphic technology offers advantages for visual processing where energy efficiency and real-time operation are critical.”

The team is also investigating materials other than MoS2 that might extend capabilities into infrared, which could enable real-time tracking of global emissions and intelligent sensing of contaminants such as toxic gases, pathogens and chemicals.

Photoactive monolayer MoS2 for spiking neural networks enabled machine vision applications’ is published in Advanced Materials Technologies (DOI: 10.1002/admt.202401677).

MULTIMEDIA AVAILABLE

Photos of the team and the neuromorphic vision device are available for download here: https://spaces.hightail.com/space/r7657uHgZL

 

Head-to-head trial compares weight loss drugs




Weill Cornell Medicine




Tirzepatide (trade name Zepbound) promoted greater weight loss in individuals with obesity than did semaglutide (trade name Wegovy) in a clinical trial that compared the safety and efficacy of the injectable drugs. In the 72-week trial—led by an investigator at Weill Cornell Medicine and NewYork-Presbyterian and conducted with the University of Texas McGovern Medical School, the David Geffen School of Medicine at the University of California, Los Angeles, the University College Dublin and Eli Lilly—participants taking tirzepatide lost about 50 pounds—or 20.2% of their body weight—compared with those on semaglutide, who lost an average of 33 pounds or 13.7% of their baseline weight.

The results of the SURMOUNT-5 phase 3b study, published May 11 in the New England Journal of Medicine, showed that when both drugs are administered at their maximum doses, participants receiving tirzepatide were more likely to reach weight loss targets and saw a greater reduction in waist circumference than those on semaglutide.

In some ways, the outcome was not a surprise. “The results are consistent with—in fact, almost identical to—what we’ve seen in trials in which these drugs were evaluated independently,” said Dr. Louis Aronne, director of the Comprehensive Weight Control Center and the Sanford I. Weill Professor of Metabolic Research at Weill Cornell Medicine and principal investigator of SURMOUNT-5. In 2022, for example, Dr. Aronne led a study showing that a 72-week course of tirzepatide at its maximum dosage reduced body weight by 20.9%; a similar study published in 2021 reported a 14.9% loss with semaglutide after 68 weeks.

A Head-to-Head Comparison

The benefit of this study—a randomized, controlled trial of 751 people with obesity but without type 2 diabetes—is that the drugs could be compared head-to-head. “Doctors, insurance companies and patients are always asking, ‘which drug is more effective?’” said Dr. Aronne, who is also an internist specializing in diabetes and obesity at NewYork-Presbyterian/Weill Cornell Medical Center. “This study allowed us to do a direct comparison.” However, the trial was not conducted as a blinded analysis—the gold standard for minimizing bias in clinical trials. Because these drugs are administered via labeled auto-injection devices, participants knew which medication they were receiving.

Eli Lilly, the company that produces tirzepatide, sponsored the study, which was conducted at 32 sites across the United States and Puerto Rico. All participants received counseling regarding diet and exercise, and the side effects associated with both drugs were very similar. For example, about 44% of individuals in each treatment arm experienced nausea and 25% reported abdominal pain.

Nearly one-third (32%) of the people who took tirzepatide achieved a body-weight reduction of at least 25%, compared with 16% of those who received semaglutide. The improved performance is likely linked to tirzepatide’s dual mechanism of action, said Dr. Aronne. Whereas semaglutide works by activating receptors for a hormone called glucagon-like peptide 1, or GLP-1, tirzepatide mimics not only GLP-1 but an additional hormone, glucose-dependent insulinotropic peptide (GIP). Together, these actions reduce hunger, lower blood-glucose levels, and affect fat cell metabolism.

“The pathways that regulate weight are incredibly complicated,” Dr. Aronne said. Targeting multiple mechanisms may pave the way to additive weight loss. Trials are underway to determine whether tirzepatide, like semaglutide, also reduces the risk of cardiovascular events, such as heart attack and stroke.

The Next Generation

Dr. Aronne and his colleagues are currently testing the next generation of weight-loss drugs, including compounds such as Eli Lilly’s retatrutide, dubbed “triple G” for the three hormones it mimics: GLP-1, GIP and glucagon. In addition to possibly being more effective, drugs like retatrutide could also potentially benefit a broader population.

“Even though drugs like tirzepatide and semaglutide work really well, better than anything we have ever seen, we still have people who don't respond to them,” said Dr. Aronne. “So, moving forward, we want to keep trying to do better.”

Dr. Louis Aronne is a paid consultant and advisory board member for Eli Lilly and Company, the study sponsor and the manufacturer of Zepbound (tirzepatide). Dr. Aronne also serves as a paid advisory board member for Novo Nordisk, the manufacturer of Wegovy (semaglutide).

 

 

New research offers hope for diabetic neuropathy sufferers


Nageotte nodules may represent uniquely effective target for new medications

\

University of Texas at Dallas

Nageotte nodules in human dorsal root ganglia in a case of diabetic peripheral neuropathy 

image: 

Human dorsal root ganglia in a case of diabetic peripheral neuropathy show formation of Nageotte nodules (circled in pink), which appear to be a strong indicator of nerve cell death.

view more 

Credit: University of Texas at Dallas




A phenomenon largely ignored since its discovery 100 years ago appears to be a crucial component of diabetic pain, according to new research from The University of Texas at Dallas’ Center for Advanced Pain Studies (CAPS).

Findings from a new study, published in Nature Communications on May 5, suggest that cell clusters called Nageotte nodules are a strong indicator of nerve cell death in human sensory ganglia. These could prove to be a target for drugs that would protect these nerves or help manage diabetic neuropathy.

“The key finding of our study is really a new view of diabetic neuropathic pain,” said Dr. Ted Price BS’97, Ashbel Smith Professor of neuroscience in the School of Behavioral and Brain Sciences, CAPS director and co-corresponding author of the study. “We believe our data demonstrate that neurodegeneration in the dorsal root ganglion is a critical facet of the disease — which should really force us to think about the disease in a new and urgent way.”

A phenomenon largely ignored since its discovery 100 years ago appears to be a crucial component of diabetic pain, according to new research from The University of Texas at Dallas’ Center for Advanced Pain Studies (CAPS).

Findings from a new study, published in Nature Communications on May 5, suggest that cell clusters called Nageotte nodules are a strong indicator of nerve cell death in human sensory ganglia. These could prove to be a target for drugs that would protect these nerves or help manage diabetic neuropathy.

“The key finding of our study is really a new view of diabetic neuropathic pain,” said Dr. Ted Price BS’97, Ashbel Smith Professor of neuroscience in the School of Behavioral and Brain Sciences, CAPS director and co-corresponding author of the study. “We believe our data demonstrate that neurodegeneration in the dorsal root ganglion is a critical facet of the disease — which should really force us to think about the disease in a new and urgent way.”

Diabetic neuropathy is one of the most common forms of neuropathic pain and affects about 11 million people — nearly one-third of the 38 million diabetics in the United States, according to the Centers for Disease Control and Prevention. It typically affects the extremities, causing sharp, shooting pain.

“Diabetic neuropathy can be debilitating,” said neuroscience research scientist Stephanie Shiers PhD’19, a co-corresponding author. “Treatment options are not great, and if the underlying diabetes is not managed, people may require amputation due to damage to the peripheral nerves to the point of loss of sensation.”

With support from a Research Program Cooperative Agreement grant (U19) from the National Institutes of Health, Shiers and other scientists at CAPS are mapping human dorsal root ganglia and other sensory system tissue to understand human pain mechanisms.

“I found an abundance of these Nageotte nodules in a subset of the dorsal root ganglia recovered from organ donors. When I looked up the medical history on these samples, they were all from individuals with diabetes,” she said. “These nodules were more prevalent in people with diabetes and even more so in those with diabetic neuropathy. Organ donors die from a range of conditions, so discovering these abnormalities in a large subset of the tissue with a similar medical history was a big break.”

Nageotte nodules are dead sensory neurons that have decayed, and what remains is a cluster of non-neuronal cells. They were first documented in 1922 in rabbits by the French neuroanatomist Jean Nageotte. In the past 100 years, these nodules have been almost entirely ignored in the research literature, only appearing in about 20 papers, many of which are a half-century old.

“They appear to be a sign of degeneration where hyperglycemia reduces neuron viability,” Shiers said. “Little has been documented about these structures’ molecular composition. Virtually nobody in the pain field had heard of them, and we knew almost nothing about their involvement in pain and neurodegeneration.”

In this study, Shiers and her colleagues sought to characterize Nageotte nodules at the molecular level. Using histology and spatial sequencing, they demonstrated that Nageotte nodules are abundant in sensory ganglia of those with diabetic neuropathy. They are mainly composed of satellite glia and non-myelinating Schwann cells.

“Intertwined with the nodule is a bundle of axons: fibers of sensory neurons that look like little neuromas. The axons there appear to sprout from sensory neurons; they are pain-sensing fibers,” Shiers said. “This appears to be a unique pathology — something never described before in humans.”

Diabetic neuropathy is one of the most common forms of neuropathic pain and affects about 11 million people — nearly one-third of the 38 million diabetics in the United States, according to the Centers for Disease Control and Prevention. It typically affects the extremities, causing sharp, shooting pain.

“Diabetic neuropathy can be debilitating,” said neuroscience research scientist Stephanie Shiers PhD’19, a co-corresponding author. “Treatment options are not great, and if the underlying diabetes is not managed, people may require amputation due to damage to the peripheral nerves to the point of loss of sensation.”

With support from a Research Program Cooperative Agreement grant (U19) from the National Institutes of Health, Shiers and other scientists at CAPS are mapping human dorsal root ganglia and other sensory system tissue to understand human pain mechanisms.

“I found an abundance of these Nageotte nodules in a subset of the dorsal root ganglia recovered from organ donors. When I looked up the medical history on these samples, they were all from individuals with diabetes,” she said. “These nodules were more prevalent in people with diabetes and even more so in those with diabetic neuropathy. Organ donors die from a range of conditions, so discovering these abnormalities in a large subset of the tissue with a similar medical history was a big break.”

Nageotte nodules are dead sensory neurons that have decayed, and what remains is a cluster of non-neuronal cells. They were first documented in 1922 in rabbits by the French neuroanatomist Jean Nageotte. In the past 100 years, these nodules have been almost entirely ignored in the research literature, only appearing in about 20 papers, many of which are a half-century old.

“They appear to be a sign of degeneration where hyperglycemia reduces neuron viability,” Shiers said. “Little has been documented about these structures’ molecular composition. Virtually nobody in the pain field had heard of them, and we knew almost nothing about their involvement in pain and neurodegeneration.”

In this study, Shiers and her colleagues sought to characterize Nageotte nodules at the molecular level. Using histology and spatial sequencing, they demonstrated that Nageotte nodules are abundant in sensory ganglia of those with diabetic neuropathy. They are mainly composed of satellite glia and non-myelinating Schwann cells.

“Intertwined with the nodule is a bundle of axons: fibers of sensory neurons that look like little neuromas. The axons there appear to sprout from sensory neurons; they are pain-sensing fibers,” Shiers said. “This appears to be a unique pathology — something never described before in humans.”

If that’s the case, the discovery could be an indicator of how to create treatment options.

“Spontaneous activity in these fibers may be what’s behind diabetic neuropathy,” Shiers said. “We also had several donors with other types of neuropathic conditions that weren’t diabetes-related, and their DRGs also had an abundance of Nageotte nodules.”

While the rare earlier papers mentioning Nageotte nodules are mostly case studies of single individuals, this study had samples from 90 people. Shiers said her documentation of axons sprouting in this manner is also novel — another aspect of this study that represents new territory.

If that’s the case, the discovery could be an indicator of how to create treatment options.

“Spontaneous activity in these fibers may be what’s behind diabetic neuropathy,” Shiers said. “We also had several donors with other types of neuropathic conditions that weren’t diabetes-related, and their DRGs also had an abundance of Nageotte nodules.”

While the rare earlier papers mentioning Nageotte nodules are mostly case studies of single individuals, this study had samples from 90 people. Shiers said her documentation of axons sprouting in this manner is also novel — another aspect of this study that represents new territory.

“This could change our basic understanding of sensory neurons. Sensory neurons are not supposed to sprout fibers from their cell bodies; they have a unique shape that we call pseudounipolar, but these diabetic sensory neurons do not look pseudounipolar — they look multipolar.” Shiers said. “We don’t know if this morphology is pathological or if we have lacked understanding of these cells in humans.”

Researchers can study human dorsal root ganglia from such a large selection of patients due to the work of the Southwest Transplant Alliance, a nonprofit organization that recovers donated organs and tissues for transplantation.

“The ability to give life to others through research is incredibly important to our donation community,” Southwest Transplant Alliance President and CEO Brad Adams said. “Knowing that your loved one’s gift led to incredible medical discoveries and advances such as this brings hope and healing to all who have lost a loved one.”

Price said, “The entire study would never have happened without them. This partnership is the most important thing that enables this work.”

Price said the research has led to new ways of thinking about neuropathy.

“In my view, one of the most important insights we gained from this work is thinking about treating diabetic neuropathic pain differently. I think what we need to focus on now is neuroprotection at early stages of disease so that these Nageotte nodules do not form in the first place.”

Other UT Dallas-affiliated authors from the Department of Neuroscience include Dr. Gregory Dussor, the James Bartlett Chair in Behavioral and Brain Sciences and department head; Dr. Diana Tavares Ferreira, assistant professor; research scientists Andi Wangzhou MS’15, PhD’21, Dr. Joseph Lesnak and Ishwarya Sankaranarayanan PhD’22; doctoral student and former Green Fellow Khadijah Mazhar BS’17; and research assistant Nwasinachi Ezeji BS’20, MS’22. Additional authors are from the Southwest Transplant Alliance and The University of Adelaide in Australia.

This research was supported by the National Institute of Neurological Disorders and Stroke through grants U19NS130608 and R01NS111929.

“This could change our basic understanding of sensory neurons. Sensory neurons are not supposed to sprout fibers from their cell bodies; they have a unique shape that we call pseudounipolar, but these diabetic sensory neurons do not look pseudounipolar — they look multipolar.” Shiers said. “We don’t know if this morphology is pathological or if we have lacked understanding of these cells in humans.”

Researchers can study human dorsal root ganglia from such a large selection of patients due to the work of the Southwest Transplant Alliance, a nonprofit organization that recovers donated organs and tissues for transplantation.

“The ability to give life to others through research is incredibly important to our donation community,” Southwest Transplant Alliance President and CEO Brad Adams said. “Knowing that your loved one’s gift led to incredible medical discoveries and advances such as this brings hope and healing to all who have lost a loved one.”

Price said, “The entire study would never have happened without them. This partnership is the most important thing that enables this work.”

Price said the research has led to new ways of thinking about neuropathy.

“In my view, one of the most important insights we gained from this work is thinking about treating diabetic neuropathic pain differently. I think what we need to focus on now is neuroprotection at early stages of disease so that these Nageotte nodules do not form in the first place.”

Other UT Dallas-affiliated authors from the Department of Neuroscience include Dr. Gregory Dussor, the James Bartlett Chair in Behavioral and Brain Sciences and department head; Dr. Diana Tavares Ferreira, assistant professor; research scientists Andi Wangzhou MS’15, PhD’21, Dr. Joseph Lesnak and Ishwarya Sankaranarayanan PhD’22; doctoral student and former Green Fellow Khadijah Mazhar BS’17; and research assistant Nwasinachi Ezeji BS’20, MS’22. Additional authors are from the Southwest Transplant Alliance and The University of Adelaide in Australia.

This research was supported by the National Institute of Neurological Disorders and Stroke through grants U19NS130608 and R01NS111929.

 

Clear waters, hidden toxins 



Study warns that viruses that kill toxic algae may actually increase risks for people and ecosystems




University of Waterloo

Jozef Nissimov 

image: 

Dr. Jozef Nissimov, professor of biology, University of Waterloo

view more 

Credit: University of Waterloo




New laboratory research shows that when viruses attack a species that forms toxic algal blooms, those thick, blue-green slicks that choke waterways and that threaten ecosystems, drinking water, and public health, what results might be even worse than before the infection. The finding questions the long-held theory among scientists that the viruses help regulate the negative effects of these blooms.  

 

A team of environmental microbiologists led by Dr. Jozef Nissimov, a professor at the University of Waterloo, has shown for the first time experimentally that when viruses infect and kill Microcystis aeruginosa, a common species responsible for harmful algal blooms (HABs), they cause the release of high levels of the toxin microcystin-LR into the water from the infected cells.  

 

The microcystin-LR toxin, a known liver toxin, remained in the water at levels roughly 40 times higher than the recommended concentration for recreational waters for several days after the infected cells died, even when the water itself appeared clear. This finding is significant because water clarity is often a prime visual cue to trigger additional testing, which can ultimately determine the safety of water for drinking and recreational use.   

 

“Our research shows us that the relationship between viruses and toxic algae is more complicated than we thought,” Nissimov said. “We need to better understand these interactions before we can consider viruses as something that acts as a natural HAB-control strategy.”  

 

HABs are a global concern. Depending on the type of species responsible for a bloom, exposure may result in skin rashes, stomach upset, liver damage and neurological problems. Pets and livestock can also develop health issues from exposure to contaminated water. In Canada, microcystins are the only algal toxins with national guidelines for water used for drinking and recreational activities, making this discovery particularly urgent for regulators and decision-makers.  

 

HABs can result in so-called dead zones, where oxygen in the water is depleted, posing a survival risk to fish and other aquatic organisms. Beyond these immediate effects, HABs often force the closure of beaches, fisheries, and nearshore recreational areas. In the Great Lakes, HABs caused by M. aeruginosa occur annually, with the most frequent and severe ones occurring in western Lake Erie.  

 

The work opens the door to further studies, including investigating how climate change might influence the dynamics between viruses, algae, and toxin release. Temperature and nutrient pollution are key factors in making HABs more frequent and widespread globally.  Another area for future exploration is how microcystin-LR and other HAB toxins get metabolised and reduced by other organisms in the environment, and how the virus infection that triggers their excess release from the infected cells can be countered.   

 

The researchers say their findings could support better forecasting and mitigation strategies for HABs, ultimately helping governments, municipalities, and water agencies make more informed, evidence-based decisions.  

 

“Viruses likely still have a very important role to play in controlling harmful blooms, but we need to ask the right questions, starting with whether the benefits of viral infection in our bodies of water outweigh its potential detrimental effects,” Nissimov said. 

 

The study, Virus Infection of a Freshwater Cyanobacterium Contributes Significantly to the Release of Toxins Through Cell Lysis, was recently published in Microorganisms