It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Tuesday, May 20, 2025
Reducing wait times for hip and knee replacement surgeries
How can we reduce wait times for much needed hip and knee replacement surgery in Canada? Coordinated referral and team-based care models show promise, according to research published in CMAJ (Canadian Medical Association Journal) https://www.cmaj.ca/lookup/doi/10.1503/cmaj.241755.
In Canada, there are long wait times for scheduled surgeries, such as hip and knee joint replacements, which can lead to worsening pain and mobility problems and affect overall health. Canada falls well behind in international comparisons of health systems based on wait times. To address this issue, some Canadian provinces have been experimenting with private for-profit delivery of some surgeries, but there are other potential solutions.
“…Other policy approaches, such as single-entry referral models and team-based care, could reduce surgical wait times substantially and improve geographic and socioeconomic inequities in wait times, which might worsen with other types of interventions,” writes Dr. David Urbach, head of the Department of Surgery and director of Perioperative Services at Women’s College Hospital and professor at the University of Toronto, Toronto, Ontario, with coauthors. “If the potential benefit of these models of care were better quantified, policy-makers and health authorities could more persuasively champion their implementation, which faces stiff resistance from some participants in the health system.”
Researchers compared 3 models of care in the study to determine if there is a better option to deliver surgery more quickly. The research included all patients referred to an orthopedic surgeon by a general practitioner or family physician in 2017 who underwent non-urgent hip or knee joint replacements and for whom there were complete wait time data. The model simulations were based on data from 17 465 surgeries on 17 132 patients, 7783 referring physicians, 274 surgeons, and 71 hospitals from 5 regions in Ontario.
The 3 models of care included single-entry referral or “central intake,” where all patients in each of 5 regions are pooled and queue for the next specialist for consultation; team-based care, where patients enter a regional pool after consultation and queue for surgery in their region; and a fully integrated model, where patients are pooled in a queue to be seen by the next available surgeon in their region then enter another queue for surgery from the next available surgeon in their region.
Both team-based and fully integrated models had much larger effects on reducing wait times than the single-entry referral model.
“Our results provide strong support for the implementation of both single-entry referral models and team-based care as a regional solution to the problem of long wait times for scheduled surgery in Canadian health systems, as well as an effective strategy to improve equity in access to health services. Adoption of these models will require strong leadership among health system leaders and the active participation of surgeons. It will also require some investment in system infrastructure, instead of one-time investments to increase surgical volumes during times of crisis,” write the authors.
Clinical entrepreneurs — physicians, nurses, and other health care professionals — who understand Canada’s health care challenges first-hand could help improve the health system and grow the economy, argue 2 physicians in a commentary published in CMAJ (Canadian Medical Association Journal) https://www.cmaj.ca/lookup/doi/10.1503/cmaj.250235.
“Successful Canadian-controlled private corporations developed by these entrepreneurs could fuel economic growth and help protect the sovereignty of our health care system,” according to Drs. Kumanan Wilson of Bruyère Health Research Institute and University of Ottawa, Ottawa, Ontario, and Dante Morra, founder of the CAN Health Network and a physician with THP Solutions and the University of Toronto, Toronto, Ontario.
However, health entrepreneurs in Canada face many barriers that will need to be addressed. These include lack of product fit for the market; risk aversion and fear of failure; financing challenges, such as access to capital for start-ups; complex intellectual property protection; and conflict of interest concerns.
“Even if a clinician entrepreneur is successful in creating a business, Canada does not have a successful record of supporting Canadian-controlled companies, and competition from international companies can be difficult to overcome,” the authors write. “Finally, there is the concern of clinicians leaving practice while Canada faces a crisis in health human resources.”
The authors recommend creating clinician entrepreneurship programs in academic centres, analogous to clinical scholar programs for scientists. These programs would provide business expertise to clinicians interested in entrepreneurship and create academic recognition and incentives for entrepreneurship. The programs could work with local business accelerators to create health-care-specific partnered entrepreneurship programs, pairing people with business expertise and clinicians to co-found companies. Changes in public health system procurement policies are key to ensure adoption of solutions created by Canadian entrepreneurs.
“Leveraging and training talented, motivated clinicians to work with partners to build successful companies can produce useful solutions to important health care problems and generate revenue to sustain our health care system. This requires a fundamental cultural change to how Canada’s health care and academic enterprise views the role of clinicians as entrepreneurs, who can drive much-needed change in Canada’s health care systems.”
Clinician entrepreneurs should be supported to address Canada’s health care challenges
Article Publication Date
20-May-2025
Monday, May 19, 2025
New scientific articles highlight potential link between microplastics in ultra-processed foods and brain health
Groundbreaking collection of four articles in Brain Medicine examines alarming "spoonful" of microplastics in human brains, with possible links to depression and dementia
This cover image depicts a human brain with colorful microplastic particles scattered across its surface, juxtaposed with a white plastic spoon as a visual representation. Research has revealed that the human brain contains approximately "a spoon's worth" of microplastics and nanoplastics, with particularly high concentrations (3-5 times greater) in individuals with dementia. The multicolored particles shown on the brain surface represent the variety of plastic types detected, with polyethylene being predominant. The image illustrates the concerning 50% increase in microplastic concentration observed between 2016 and 2024, highlighting the rapid infiltration of these synthetic materials into our most protected organ.
NEW YORK, New York, USA, 20 May 2025 – A groundbreaking collection of four papers published in the May issue of Brain Medicine synthesizes mounting evidence that microplastics from ultra-processed foods may be accumulating in human brains and potentially contributing to the rising global rates of depression, dementia, and other mental health disorders. The papers provide the most comprehensive analysis to date of how these tiny plastic particles might be affecting brain health through multiple interconnected biological pathways.
The Plastic Spoon in Your Brain
The striking cover of Brain Medicine's May 2025 issue depicts a human brain stippled with colorful microplastic particles alongside a plastic spoon – a visual that powerfully captures the main finding that human brains contain approximately "a spoonful" of microplastic material. This alarming concept is examined in depth across all four articles in this special collection, including a peer-reviewed commentary previously published online titled "Human microplastic removal: what does the evidence tell us?" (https://doi.org/10.61373/bm025c.0020) that now appears in the May issue alongside three new papers being released today.
The featured peer-reviewed viewpoint article by Dr. Nicholas Fabiano from the University of Ottawa, Dr. Brandon Luu from the University of Toronto, Dr. David Puder from Loma Linda University School of Medicine, and Dr. Wolfgang Marx from Deakin University's Food & Mood Centre, titled "Microplastics and mental health: The role of ultra-processed foods" (https://doi.org/10.61373/bm025v.0068), builds upon their earlier commentary on microplastic accumulation in human tissue, "Human microplastic removal: what does the evidence tell us?" (https://doi.org/10.61373/bm025c.0020). This new viewpoint paper synthesizes emerging evidence to propose a novel hypothesis connecting ultra-processed food consumption, microplastic exposure, and mental health outcomes.
"We're seeing converging evidence that should concern us all," explains Dr. Fabiano. "Ultra-processed foods now comprise more than 50% of energy intake in countries like the United States, and these foods contain significantly higher concentrations of microplastics than whole foods. Recent findings show these particles can cross the blood-brain barrier and accumulate in alarming quantities."
The Mental Health Connection
The researchers cite substantial evidence linking ultra-processed food consumption with adverse mental health outcomes. A recent umbrella review published in The BMJ found that people who consumed ultra-processed foods had a 22% higher risk of depression, 48% higher risk of anxiety, and 41% higher risk of poor sleep outcomes.
What makes their hypothesis particularly compelling is the novel suggestion that microplastics—tiny plastic particles less than 5mm in size—may be a missing link in this relationship. The researchers point to disturbing data showing that foods like chicken nuggets contain 30 times more microplastics per gram than chicken breasts, highlighting the impact of industrial processing.
The hypothesis gains further credibility from recent findings published in Nature Medicine that demonstrated alarming microplastic concentrations in the human brain—approximately "a spoon's worth" according to the researchers—with levels three to five times higher in those with documented dementia diagnoses.
Shared Mechanisms of Harm
"This hypothesis is particularly compelling because we see remarkable overlap in biological mechanisms," notes Dr. Marx. "Ultra-processed foods have been linked to adverse mental health through inflammation, oxidative stress, epigenetics, mitochondrial dysfunction, and disruptions to neurotransmitter systems. Microplastics appear to operate through remarkably similar pathways."
The viewpoint article raises an intriguing question: Could the microplastic content of ultra-processed foods be partially responsible for their observed negative mental health effects? To study this relationship more systematically, the authors propose the development of a Dietary Microplastic Index (DMI) to quantify exposure through food consumption.
Possible Removal Pathways
Complementing the viewpoint article is a peer-reviewed Brevia research paper titled "Therapeutic apheresis: A promising method to remove microplastics?" (https://doi.org/10.61373/bm025l.0056) by Dr. Stefan Bornstein and colleagues. This paper, also published in the May issue, examines preliminary evidence that extracorporeal therapeutic apheresis—a technique that filters blood outside the body—may have the potential to remove microplastic particles from human circulation.
"While we need to reduce our exposure to microplastics through better food choices and packaging alternatives, we also need research into how to remove these particles from the human body," notes Dr. Bornstein. "Our early findings suggest that apheresis might offer one possible pathway for microplastic removal, though much more research is needed."
A Call to Action
The issue is further contextualized by a powerful guest editorial by Dr. Ma-Li Wong titled "Una cuchara de plástico en tu cerebro: The calamity of a plastic spoon in your brain" (https://doi.org/10.61373/bm025g.0062), which frames the collection of papers as not just a scientific warning but a paradigm shift in how we must think about environmental contaminants and brain health.
"What emerges from this work is not a warning. It is a reckoning," writes Dr. Wong. "The boundary between internal and external has failed. If microplastics cross the blood-brain barrier, what else do we think remains sacred?"
The authors of all four papers emphasize that while more primary research is needed, their analyses add another dimension to the growing case for reducing ultra-processed food consumption and developing better methods to detect and potentially remove microplastics from the human body.
"As the levels of ultra-processed foods, microplastics, and adverse mental health outcomes simultaneously rise, it is imperative that we further investigate this potential association," concludes Dr. Fabiano. "After all, you are what you eat."
The articles on microplastics and brain health from the May 2025 issue of Brain Medicine will be available on 20 May 2025 via Open Access at the following URLs:
About Brain Medicine: Brain Medicine (ISSN: 2997-2639, online and 2997-2647, print) is a high-quality medical research journal published by Genomic Press, New York. Brain Medicine is a new home for the cross-disciplinary pathway from innovation in fundamental neuroscience to translational initiatives in brain medicine. The journal's scope includes the underlying science, causes, outcomes, treatments, and societal impact of brain disorders, across all clinical disciplines and their interface.
ITHACA, N.Y. - People have assumed climate change solutions that sequester carbon from the air into soils will also benefit crop yields.
But a new study from Cornell University finds that most regenerative farming practices to build soil organic carbon – such as planting cover crops, leaving stems and leaves on the ground and not tilling – actually reduce yields in many situations.
The computer model analysis showed that global adoption of such practices to improve soil health can benefit either greenhouse gas mitigation or crop yields but rarely both.
The predictions will help farmers, policymakers and sustainability professionals mix and match optimal management plans based on location, as different practices will work better or worse depending on local conditions. For example, the model predicted that climate mitigation and improved yields had the best chance of occurring together when grains are planted, especially in soils with high clay content or that have limited nutrients.
“For the first time, we can have contextualized information about how farmers can choose the optimal mix of practices that meet their needs to maintain crop yields while also providing climate change mitigation,” said Dominic Woolf, senior research associate in the School of Integrative Plant Science, Soil and Crop Sciences Section, in the College of Agriculture and Life Sciences at Cornell University.
Woolf is principal investigator of the project and senior author of the study published May 19 in Nature Climate Change. Shelby McClelland, a postdoctoral researcher at New York University’s Department of Environmental Studies, formerly in Woolf’s lab at Cornell, is the paper’s first author.
For farmers, climate mitigation strategies include cover crops that are planted and left in place. Cover crops benefit farms by adding soil organic carbon (carbon from organic matter in soils), improving soil health, reducing soil erosion, cycling nutrients and converting nitrogen to forms usable by plants (when legumes are planted). They also offer off-farm benefits of protecting surface water quality and mitigating climate change, by pulling carbon from the air for growing steams, leaves and roots, and sequestering it from being released back into the atmosphere. Other practices, such as eliminating tillage, reduce erosion, limit soil carbon losses and disruption of soil structure.
The global computer model compared soil organic carbon changes, greenhouse gas release and yield outcomes of cropland climate mitigation practices with conventional cropland management. The researchers simulated a set of scenarios through the end of the century, including various combinations of four common management practices: planting grass cover crops, planting legume cover crops, zero-tillage, and leaving crop residues in fields.
The analysis showed that grass cover crops combined with no tilling led to the highest potential for limiting greenhouse gasses, but were the worst for crop yields. Legume cover crops with no tilling provided higher crop yields but close to 70% lower climate benefits. Reduced yields were found to be most likely in drier climates where cover crops compete for available water. Also, in some regions, these climate mitigation practices led to higher greenhouse gas emissions than conventional farming due to increased soil nitrous oxide, which is 273 times more potent as a greenhouse gas than CO2.
“We found a strong synergy in many locations between cover cropping and conducting no till,” McClelland said. “If you do both those practices together, in many cases, that allows you to increase soil organic carbon much faster than individual practices alone, which offsets negative effects from things like nitrous oxide emissions,” she said. Lowering nitrogen inputs into soil may also help address nitrous oxide emissions.
The authors found that in order to maintain crop yields to feed a growing global population, the maximum greenhouse gas mitigation through 2100 would be about 85% lower than if yields were not considered and farming practices centered around optimal climate mitigation strategies. “So tradeoffs have a massive impact in terms of what’s achievable at the global scale,” Woolf said.
Co-authors include researchers from The Nature Conservancy, the Environmental Defense Fund, Colorado State University, and the Woodwell Climate Research Center.
The research was funded by the National Institute of Food and Agriculture, a U.S. Forest Service contract through an interagency agreement with the U.S. Environmental Protection Agency, the Nature Conservancy, the Environmental Defense Fund, the Bezos Earth Fund, King Philanthropies, and Arcadia, a charitable fund.
Journal
Nature Climate Change
Capuchin monkeys develop bizarre “fad” of abducting baby howlers
How cameras on a remote island captured the origin and spread of a novel social tradition
Credit: Brendan Barrett / Max Planck Institute of Animal Behavior
On an island off the coast of Panama lives a population of wild primates with a remarkable culture. White-faced capuchins on Jicarón Island in Coiba National Park use stone tools; and scientists have been monitoring this unique tradition with an array of motion-triggered cameras on the island since 2017. In 2022, doctoral researcher Zoë Goldsborough was looking through the camera trap footage when she found an unusual sighting, something they had never seen in the previous five years of data: a capuchin monkey carrying an infant howler monkey on his back.
“It was so weird that I went straight to my advisor’s office to ask him what it was,” remembers Goldsborough who is conducting her dissertation at MPI-AB. The biologists knew it was a rare animal behavior and so they immediately started investigating. If there was to be more evidence of this occurring on the island, they were confident they would find it: “We had all the footage from cameras on Jicarón for the whole year,” says Brendan Barrett, a group leader at MPI-AB and Goldsborough’s advisor, “so we could reconstruct the scene to see if this weird behavior was just a one-off, or something bigger.”
The influencer
Goldsborough manually dug through the tens of thousands of images and videos collected by all cameras deployed around this time period. She found not one, but four different howler infants being carried. In nearly all cases, the carrier was the same individual: a subadult male she named Joker. These observations raised several questions. How did Joker get these infants? And why did he carry them for days at a time?
“At first, we thought it could be adoption,” says Goldsborough. Anecdotes exist of some animals adopting babies of other species. In a well-known case from 2006, a pair of capuchins adopted a baby marmoset and succeeded in raising it into adulthood. But there was a problem with this interpretation: animal adoption is almost always carried out by females, who presumably do it to practice “caring” for infants. “The fact that a male was the exclusive carrier of these babies was an important piece of the puzzle,” she adds.
Then, the trail went cold. Goldsborough found no evidence of howler carrying for months. “We’d decided that it was one individual trying something new,” says Barrett, “which is not uncommon to see among capuchins. These are deeply curious animals who are constantly exploring the forest and figuring out how they can interact with their world.”
Eventually, though, the researchers struck the motherlode: they discovered a series of images and video, timestamped five months later, of more howler infants being carried. The authors called on a howler monkey expert, Lisa Corewyn at Ithaca College, who verified that the babies were separate individuals. “We assumed that Joker was at it again,” says Goldsborough. But they soon realized that the carrying behavior had in fact spread to four other capuchins—all young males.
The spread
Over the course of 15 months, these five capuchins carried 11 different howler monkeys for up to 9-day periods. The camera footage showed the howler babies clinging to the backs or bellies of their young male carriers who appeared to be going about their normal business of travelling or using tools to crack open food sources. The researchers collated the footage on an interactive website documenting the spread of the behavior.
“The complete timeline tells us a fascinating story of one individual who started a random behavior, which was taken up with increasing speed by other young males,” says Barrett. The authors describe this as a social tradition or cultural fad—a behavior that spreads in a population through social learning. It parallels trends observed in other animals, such as killer whales donning “salmon hats” or chimpanzees wearing a blade of grass in their ears like an accessory.
Social learning gone wrong?
The implications of the capuchins’ fashion fad, however, are more than skin deep. The howler babies, all less than four weeks old, appear to have been abducted from their parents who were captured on camera calling to infants from nearby trees. Four babies were observed to have perished. The authors suspect that none of the babies survived. "The capuchins didn’t hurt the babies,” stresses Goldsborough, “but they couldn’t provide the milk that infants need to survive.”
As is often the case in the natural world, one animal’s loss is another animal’s gain. But what the capuchins gain from this social tradition is a mystery. The males don’t eat the infants, they don’t play with them, and they don’t receive more attention from their group mates while carrying an infant. “We don’t see any clear benefit to the capuchins,” says Goldsborough “but we also don’t see any clear costs, although it might make tool use a little trickier.”
Rethinking animal culture
The research offers the first known documentation of a social tradition in which animals repeatedly abduct and carry infants of another species—without any clear benefit to themselves. It highlights the ways in which animal culture can parallel our own. Says Barrett: “We show that non-human animals also have the capacity to evolve cultural traditions without clear functions but with destructive outcomes for the world around them.”
This, he says, points to a compelling line of inquiry. “The more interesting question is not ‘why did this tradition arise?’ but rather ‘why here?’”
Not just tool users
The white-faced capuchins on Jicarón island have developed a unique tradition of using stone tools to crack open hard foods like nuts and shellfish. Interestingly, the capuchins that use tools on Jicarón are only males—just like the howler kidnappers—hinting that these two socially learned traditions might spring from the same source: boredom.
Meg Crofoot, managing director at the MPI-AB and one of the founders of this project, says: “Survival appears easy on Jicarón. There are no predators and few competitors, which gives capuchins lots of time and little to do. It seems this ‘luxurious’ life set the scene for these social animals to be innovators. This new tradition shows us that necessity need not be the mother of invention. For a highly intelligent monkey living in a safe, perhaps even under-stimulating environment, boredom and free time might be sufficient.”
Looking forward
The study’s camera trapping period ran from January 2022 to July 2023, and the team does not know to what extent the tradition persisted afterwards as all data has not yet been analyzed. But, if the behavior spreads to other capuchin groups or continues to impact howlers, which are an endangered species on Jicarón, it could become a conservation issue in Coiba National Park.
“Witnessing the spread of this behavior had a profound effect on all of us,” says Crofoot. “We therefore feel even more responsible to keep learning from this natural population of primates who, to our knowledge, are the only ones on earth to be practicing this strange tradition.”
