Breaking Research

Children learn even when they're not paying attention, U of T psychologists find

Christopher.Sorensen — Thu, 16 Jan 2025 15:30:10 +0000

Children learn even when they're not paying attention, U of T psychologists find

Christopher.Sorensen Thu, 01/16/2025 - 10:30

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Children learn just as much whether they're trying to or not, while adults tend to ignore information they aren't paying attention to, according to a new study led by ��߲ݴ�ý psychologists (photo by Adobe Stock)

Michael Pereira

Topic

Breaking Research

Faculty of Arts & Science

Psychology

Research & Innovation

Subheadline

“Don’t get mad at the little boy who’s doing jumping jacks while you’re reading a book"

Are you a parent or teacher frustrated that the children in your life can’t seem to pay attention when you’re trying to teach them something? You don’t need to be, say psychologists at the ��߲ݴ�ý.

New research from the department of psychology in the Faculty of Arts & Science finds children learn just as much whether they’re trying to or not – adults, on the other hand, tend to ignore information that they aren’t paying attention to.

The findings are outlined in a new study published in the journal Psychological Science.

“Don’t get mad at the little boy who’s doing jumping jacks while you’re reading a book,” says the study’s senior author Amy Finn, associate professor in the department of psychology who leads the Learning and Neural Development lab. “He’s probably still listening and learning even though it doesn’t necessarily look like it.”

For the study, the research team – which included U of T alumni Marlie Tandoc, Bharat Nadendla and Theresa Pham – tested how much children and adults learned about drawings of common objects after two different experiments.

In the first, they told participants to pay attention to the drawings. In the second, participants were told to ignore the drawings and complete an entirely different task. After each scenario, participants had to identify fragments of the drawings they saw as quickly as possible.

They found that children learned about the drawings just as well across both scenarios, while adults learned more when told to pay attention to the drawings – in other words, the children’s learning wasn’t negatively impacted when they weren’t paying attention to the information they were tested on.

Children’s selective attention, or their ability to focus on a specific task and tune out distractions, develops slowly and doesn’t fully mature until early adulthood.

Previous research has found that unlike adults, a child’s brain treats information that they are told to pay attention to similarly to information they are not told to attend to. That is likely one of the reasons why children are so good at picking up languages spoken around them.

“As adults, we really filter what we’re learning through our goals and task demands, whereas kids are absorbing everything regardless of that – seemingly without even trying,” says Tandoc, former lab manager of the Learning and Neural Development lab and a PhD candidate at the University of Pennsylvania.

Although returning to a child-like state of learning might sound appealing, selective attention does hold several benefits. Across experiments, attentional instruction was found to boost learning in adults. In other words, adults learn better when told what information is most important.

The research has the potential to influence how parents, teachers and curriculum designers think about how children and adults learn. For instance, for children, the findings underline the benefits of play and immersive learning. For adults, defining a clear task or goal at the beginning of a class or workshop is important for learning outcomes.

“For me, when I’m hanging out with my five-year-old, I’m less worried now than I was otherwise about whether or not he is learning something if it doesn’t seem like he is paying attention,” says Finn.

Researchers develop biodegradable electrodes that may help repair damaged brain tissue

Christopher.Sorensen — Mon, 13 Jan 2025 14:57:52 +0000

Researchers develop biodegradable electrodes that may help repair damaged brain tissue

Christopher.Sorensen Mon, 01/13/2025 - 09:57

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From left: Professor Cindi Morshead, PhD student Tianhao Chen and Professor Hani Naguib led research to develop a flexible, biodegradable electrode capable of stimulating neural precursor cells in the brain (supplied images, Chen by Qin Dai)

Qin Dai

Topic

Breaking Research

Temerty Faculty of Medicine

Faculty of Applied Science & Engineering

Graduate Students

Research & Innovation

Subheadline

“Our plan is to further develop this technology by creating multimodal, biodegradable electrodes that can deliver drugs and gene therapies to the injured brain”

��߲ݴ�ý researchers have developed a flexible, biodegradable electrode capable of stimulating neural precursor cells (NPCs) in the brain – a device capable of delivering targeted electrical stimulation for up to seven days before it dissolves naturally.

By harnessing the body’s innate repair mechanisms, the researchers’ approach represents a potential step forward in the treatment of neurological disorders that are a leading cause of disability worldwide. While neurological disorders often result in irreversible cell loss, stimulating NPCs – rare cells capable of repairing neural tissue – has shown promise when it comes to expanding limited treatment options.

However, existing methods such as transcranial direct current stimulation lack precision and can damage tissue. The electrode developed by U of T researchers, on the other hand, provides precise, safe and temporary stimulation without requiring subsequent surgical interventions.

“Our findings demonstrate that this electrode can stimulate neural repair in a controlled, temporary manner, which is crucial for avoiding complications associated with permanent implants,” says Tianhao Chen, a PhD student in biomedical engineering who is the study’s lead author.

The research, published in a recent issue of Biomaterials, was led by Hani Naguib, a professor in the departments of materials science and engineering and mechanical and industrial engineering in the Faculty of Applied Science & Engineering, and Cindi Morshead, a professor of surgery in the Temerty Faculty of Medicine who is cross-appointed to the Institute of Biomedical Engineering.

“Neural precursor cells hold significant potential for repairing damaged brain tissue, but existing methods for activating these cells can be invasive or imprecise,” Morshead says.

“Our biodegradable electrode provides a solution by combining effective stimulation with reduced patient risk.”

To design the biodegradable neural probe, the team focused on materials that provided both biocompatibility and tunable degradation rates.

Poly(lactic-co-glycolic) acid (PLGA), a flexible material approved by the U.S. Food and Drug Administration, was chosen for the substrate and insulation layer due to its predictable degradation based on monomer ratios and minimal inflammatory effects.

Molybdenum was selected for the electrode itself due to its durability and slow dissolution – both qualities essential for maintaining structural integrity during the intended one-week stimulation period.

The electrodes were implanted in pre-clinical models and demonstrated the ability to stimulate NPCs effectively, increasing their numbers and activity without causing significant tissue damage or inflammation. This testing ensured the electrodes’ safety and efficacy for neural repair stimulation within the targeted time frame.

“Our plan is to further develop this technology by creating multimodal, biodegradable electrodes that can deliver drugs and gene therapies to the injured brain,” says Morshead.

“We have exciting data to show that activating brain stem cells with our electrical stimulation devices improves functional outcomes in a preclinical model of stroke.”

Why do we prefer curves over straight edges? Researchers probe the brain for clues

Christopher.Sorensen — Fri, 10 Jan 2025 17:06:08 +0000

Why do we prefer curves over straight edges? Researchers probe the brain for clues

Christopher.Sorensen Fri, 01/10/2025 - 12:06

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Researchers found regions in the brain that are sensitive to scenes people perceive to be curvy, but only when they are judging its beauty (supplied image)

Michael Pereira

Topic

Breaking Research

Faculty of Arts & Science

Graduate Students

Psychology

Research & Innovation

Subheadline

“Artists and designers are way ahead of scientists. They already use organic, curvy lines to evoke a sense of comfort, aesthetic pleasure and hominess”

For over 100 years, psychologists have known that most people prefer curviness over angularity in practically everything – from lines and shapes to faces, paintings and interior spaces.

Moreover, the phenomenon has been observed across cultures, in infants and even in great apes.

Yet, it remains unclear what it is about our perception of curvature that translates into this widespread preference.

“Now we have this advantage that we can probe the brain to see the mechanisms that are really driving this process,” says Oshin Vartanian, an associate professor in the department of psychology at the ��߲ݴ�ý who is appointed to Defence Research and Development Canada.

Using brain imaging data and computational measures of curvature, Vartanian worked with U of T PhD student Delaram Farzanfar, Dirk Bernhardt-Walther, a U of T associate professor of psychology, and an international group of collaborators to solve the mystery.

For the study, published recently in Scientific Reports, participants completed two tasks when presented with images of curvy and angular interior spaces. They judged each as either “beautiful” or “not beautiful” and decided whether they would choose to “enter” or “exit” the space.

Researchers found that there are regions in the brain that are sensitive to scenes participants perceive to be curvy, but only when they are judging its beauty. When a participant is asked to decide whether they would enter or exit the space, those regions are not sensitive to perceived curvature.

This observation suggests that the context within which we perceive curvature makes a difference in how our brain responds to it.

The regions of the brain that lit up to scenes participants perceive to be curvy, in the fusiform gyrus, are involved in higher-order visual processing like object recognition. They are also sensitive to the perception of faces.

In other words, these findings suggest that the region of our brain that specializes in distinguishing one face from another might also be sensitive to processing curvature in other contexts – such as looking at architectural spaces.

Examples of the experimental stimuli (n = 200). The stimuli in the top and bottom rows were categorized as “curvilinear” and “rectilinear” respectively by the two experts in Vartanian et al. The number underneath each stimulus represents its associated computational curvature value (supplied image)

Researchers also found that images of spaces that participants perceived as curvy did not always match with computational measures of those same spaces. However, a region in the primary visual cortex shows sensitivity to computational curvature, regardless of the task.

“It’s entirely possible that when a person looks at an image, they form a mental representation that’s three-dimensional,” Vartanian says. Such a representation eludes mathematical measurements of two-dimensional images.

Bernhardt-Walther adds that, going forward, researchers need to have a broader view of what parts of an image translate into a sense of curviness that people perceive as aesthetically pleasant.

“Artists and designers are way ahead of scientists. They already use organic, curvy lines to evoke a sense of comfort, aesthetic pleasure and hominess,” says Bernhardt-Walther. “Our work provides a scientific underpinning for their intuitions and may guide them on using curvature more deliberately as a design element to generate aesthetically pleasing forms or, alternatively, to use angularity to challenge and engage the viewers.”

Farzanfar, meanwhile, says the research is not only relevant to the work of neuroscientists and psychologists, but to artists, designers, architects and city planners.

“I think as we understand how spaces impact our mood and cognition, we can create better environments for our health and enrich the experience of modern life for many people,” she says.

Timing exercise around meals can affect women's blood sugar, appetite: Study

Christopher.Sorensen — Wed, 08 Jan 2025 19:17:35 +0000

Timing exercise around meals can affect women's blood sugar, appetite: Study

Christopher.Sorensen Wed, 01/08/2025 - 14:17

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(photo by Milorad Kravic/Getty Images)

Jelena Damjanovic

Topic

Breaking Research

Faculty of Kinesiology & Physical Education

Research & Innovation

Subheadline

In healthy females, a post-meal rise in blood sugar was lower if they waited until after breakfast to exercise

Researchers at the ��߲ݴ�ý have found that in healthy females, a post-meal rise in blood sugar was lower if they waited until after breakfast to exercise.

The researchers in the Faculty of Kinesiology & Physical Education (KPE) also measured perceptions of appetite before and after exercise – and once every hour in the post-exercise period.

They found that study participants who exercised after eating breakfast had lower appetite immediately before and after the exercise session, compared to those who exercised before eating.

“It’s normal for blood sugar to increase after eating carbohydrate-containing meals,” says Alexa Govette, a PhD candidate in KPE who co-wrote the study published in Applied Physiology, Nutrition and Metabolism with Assistant Professor Jenna Gillen. “However, exaggerated spikes in blood glucose concentrations after eating are associated with increased risk for cardiometabolic diseases, like type 2 diabetes.”

While low-volume, high-intensity interval exercise has been shown to reduce the increase of blood sugar in laboratory settings, these protocols often involve specialized exercise equipment, says Govette. A novel aspect of this study was that the interval exercise protocol was equipment-free, consisting of only bodyweight movements such as jumping jacks, burpees and mountain climbers.

The timing of when you eat around exercise has also been shown to influence blood glucose concentrations and perceptions of appetite, but this has not been studied in the context of interval exercise or in an at-home setting.

“To our knowledge, this is the first study to investigate how exercise-meal timing influences blood glucose responses to high-intensity interval exercise in females,” says Govette. “It is also the first study to assess the influence of exercise-meal timing on appetite perceptions in healthy females following bodyweight interval exercise.”

Govette says very few studies have examined the effects of exercise-meal timing in a female population, so this study in healthy young women provides much needed evidence for how blood glucose concentrations are influenced by the timing of exercise around meals.

From a practical perspective, the study offers new insight into the effect of exercising around meals on blood glucose regulation and perceptions of appetite in an at-home/non-laboratory environment.

“This study was conducted during the COVID-19 pandemic when research restrictions precluded us from conducting in-person exercise studies in our laboratory,” says Gillen. “In the end, this allowed us to investigate how the timing of exercise around meals influences blood sugar control in an at-home setting, which hadn’t been done previously.

“Given the growing popularity of at-home and virtual workouts, our findings may be of interest to individuals who prefer to exercise at home or those that do not have access to exercise equipment.”

Next, the researchers hope to investigate the effects of exercise-meal timing on blood sugar regulation in females who are at-risk or who are living with type 2 diabetes, given that exercise-induced reductions in blood glucose increases have more clinical relevance in these populations.

“We currently have ongoing work that is comparing at-home bodyweight interval exercise to other forms of exercise in females with cardiometabolic risk factors to help address this question,” says Govette. “Additionally, it would be interesting to explore the influence of meal timing around bodyweight interval exercise over the course of several weeks to months, to assess the long-term effects on blood glucose regulation.”

FOMO is about who you're with - not what you're doing: Study

Christopher.Sorensen — Wed, 08 Jan 2025 16:35:17 +0000

FOMO is about who you're with - not what you're doing: Study

Christopher.Sorensen Wed, 01/08/2025 - 11:35

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Fans share a moment during a Taylor Swift concert in the Netherlands earlier this year (photo by Aldara Zarraoa/Getty Images for TAS Rights Management)

Ken McGuffin

Topic

Breaking Research

Global

Research & Innovation

Rotman School of Management

U of T Scarborough

Subheadline

Researchers say the idea of FOMO, or "fear of missing out," has more to do with potential for social bonding than it does with the opportunity to participate in a fun activity

Think of FOMO – fear of missing out – and you might think of missing the concert of the year, an epic party or a big family gathering.

But research published recently in the Journal of Personality and Social Psychology shows that FOMO has far more to do with people, social status and belonging – and is not just a social media-fuelled phenomenon.

“FOMO refers to the anxiety that people feel when they miss out on a social group experience – and, specifically, the bonding that their group shared at the experience – because they worry that missing out will negatively affect their connection and future belonging with the group,” says Cindy Chan, an assistant professor of marketing at the ��߲ݴ�ý Scarborough and the Rotman School of Management.

Cindy Chan (photo by Ken Jones)

Chan and fellow researcher Jacqueline Rifkin, assistant professor of marketing at Cornell University, say the study sprung from their curiosity about what was behind the acronym’s growing popularity in the early 2010s.

“The term FOMO was being used more often and we wondered what this meant,” says Chan. “What were people afraid of missing out on? What situations or events might make someone feel FOMO?”

Joined by University of Pennsylvania marketing professor Barbara Kahn, the group set up multiple experiments, including with teenaged summer camp attendees and online participants, using scenarios such as missed concerts, group retreats and group initiation events, as well as exposure to participants’ own social media feeds.

They found that while FOMO was initiated by worries about missing a social bonding experience with a valued group, it got its fuel from a sometimes exaggerated sense of the potential relationship consequences for missing out and was worse for people who already tended to be socially anxious. Distinct from disappointment about missing an enjoyable experience, FOMO could even be felt in relation to potentially unpleasant scenarios such as a team-building event with demanding, stressful activities.

While the researchers did not specifically study whether FOMO is a byproduct of social media engagement, they note that the key mechanism that underpins FOMO can be experienced without the use of technology like a mobile phone or social media platforms.

“It’s possible that social media may mean we are reminded more of social events we miss, because others may make social media posts about the event,” Chan says. “So this could mean we experience FOMO more, or more often.”

It may be possible to bring people back from the FOMO brink. Negative feelings were reduced for people whose FOMO was triggered by exposure to social media posts about events they had missed but who were then invited to reflect on a past valued group event they did attend, thereby reaffirming their sense of belonging.

“This research reveals how central social relationships are in people’s experience of FOMO and reinforces how important these relationships are to our personal and emotional well-being,” says Chan.

The researchers are currently working on a paper about how FOMO can enhance customer engagement with corporate brands.

One in four Canadian women unaware of folic acid's importance during pregnancy: Study

Christopher.Sorensen — Tue, 07 Jan 2025 20:10:40 +0000

One in four Canadian women unaware of folic acid's importance during pregnancy: Study

Christopher.Sorensen Tue, 01/07/2025 - 15:10

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(photo by Oscar Wong/Getty Images)

Matthew Tierney

Topic

Breaking Research

Temerty Faculty of Medicine

Research & Innovation

Subheadline

“We are currently experiencing a crisis of family doctors in the country. The shortage makes me worry about what may happen to awareness levels in the coming years”

Approximately one in four women in Canada are unaware of the benefits of taking folic acid before and during pregnancy to prevent certain birth defects – a percentage that has not improved in more than a decade.

In a recent paper published in the Journal of Obstetrics and Gynaecology Canada, researchers at Sinai Health and the ��߲ݴ�ý analyzed data from the Canadian Community Health Survey conducted by Statistics Canada in 2017 and 2018.

“We compare this data to the last national study on prevalence of folic acid supplementation awareness in 2006–2007, which utilized data from the Canadian Maternity Experiences Survey,” says Vrati Mehra, a fourth-year medical student in U of T’s Temerty Faculty of Medicine.

“We see almost no change in awareness levels from then till now. The numbers have essentially remained the same.”

Mehra is lead author of the paper along with Ellen Greenblatt, John Snelgrove and Claire Jones – all clinicians in the department of obstetrics and gynaecology at Mount Sinai Hospital and faculty members in the department of obstetrics and gynaecology in U of T’s Temerty Faculty of Medicine. Professor Hala Tamim from York University also contributed to the study.

Researchers Claire Jones, left, and medical student Vrati Mehra are study co-authors (supplied images)

“Vrati had worked on a previous project of ours, a prenatal program design that involved interviewing pregnant participants,” says Jones, who is also the program director for gynecologic reproductive endocrinology and infertility residency at U of T.

“Hearing many admit they did not know about supplementing with folic acid inspired her to look further into it – a good example of how anecdotal evidence can suggest fruitful research paths.”

In the early 1990s, researchers showed that folic acid could prevent open neural tube defects. The neural tube is formed in the third and fourth weeks of pregnancy and develops into the nervous system: the spinal cord and brain. Defects lead to higher incidence of miscarriages, or debilitating conditions such as spina bifida or anencephaly at birth.

“Although we typically get enough folic acid for daily functioning, the requirement increases significantly during pregnancy to support the development of a growing baby,” says Mehra. “So, in the early 2000s, the government mandated that companies fortify pasta, breads, cereal and other grain foods with folic acid.”

The folic acid fortification came with targeted public ad campaigns that successfully raised awareness levels among Canadian females from between 25 and 50 per cent in the early 2000s to between 70 and 75 per cent in 2007.

“However, since then, the public campaigns have become more passive,” says Mehra. “Posters by the Public Health Agency of Canada are available online for those seeking information about folic acid. However, to my knowledge, there are no active campaigns targeting people who might be completely unaware of its importance.”

The study also found that certain socioeconomic patterns had persisted over the decade. People who were younger were more likely to be unaware of folic acid, as were people with lower income or less education. Landed immigrants were three times more likely to be unaware, on average.

Some of the disparities may be explained by how health information circulates, says Mehra.

“People get info from their family doctors, or from a public campaign poster in a health-care provider’s office. Those who only see a doctor after finding out that they are pregnant, or don’t have regular follow-up, have fewer chances to learn about folic acid,” she says.

“We are currently experiencing a crisis of family doctors in the country. The shortage makes me worry about what may happen to awareness levels in the coming years.”

Possible solutions include incorporating information about folic acid’s benefits before and during pregnancy to the high school sexual health curriculum, which already covers content on contraception and pregnancy. The addition would emphasize the importance of folic acid for pregnant individuals and advise those planning to become pregnant to begin taking supplements at least three months prior to conception and during their pregnancy.

The researchers say it may also be beneficial to target newcomers to Canada.

“I was once an immigrant,” says Mehra. “I remember accompanying my parents to the ServiceOntario Centre to get our health cards. Including a simple line in multiple languages about folic acid, either in the paperwork or displayed on posters, could help.

“We also visited other public spaces like libraries and community centres, which are ideal for informative posters.

“A collective effort from the government, health-care providers, the education system and the immigration system would make a big difference.”

Forests may be more resilient to climate change than previously thought: Study

Christopher.Sorensen — Mon, 06 Jan 2025 14:23:54 +0000

Forests may be more resilient to climate change than previously thought: Study

Christopher.Sorensen Mon, 01/06/2025 - 09:23

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(photo by Photo Image Library)

Topic

Breaking Research

Climate Change

Research & Innovation

Sustainability

U of T Scarborough

Subheadline

An international team of researchers studied the combined effects of rising temperatures and increased nitrogen in the atmosphere due to the burning of fossil fuels

Forests may be more resilient to climate change than previously thought.

A team of international researchers have found that increased inputs from plant roots can keep carbon levels in soil stable even as temperatures and nitrogen deposits in the atmosphere rise.

The collaborative research project, published in Nature Ecology and Evolution, looked at the effects of increased temperatures due to climate change and increased nitrogen in the atmosphere released by burning fossil fuels – two environmental threats that had been studied separately.

“There is a lot of uncertainty when these two antagonistic stressors are combined – which is why this study is so significant,” says Myrna Simpson, a professor in the department of physical and environmental sciences at the ��߲ݴ�ý Scarborough who collaborated on the research conducted in the Harvard Forest in Massachusetts.

Earlier studies showed that increased temperatures caused forests to lose carbon while increases in nitrogen can result in carbon buildup. And warming alone can cause soil to lose carbon since heat speeds up decomposition and decomposition converts the carbon into CO2.

But the research team – led by Melissa Knorr and Serita Frey of the department of natural resources and the environment at the University of New Hampshire – found when rising temperatures were coupled with higher nitrogen levels, the plants added more carbon to soil by increasing their growth, activity and root turnover (the rate that their roots grow, die and decompose), maintaining soil carbon levels.

Myrna Simpson (photo by Ken Jones)

Simpson, an associate director of the Environmental NMR Centre, has collaborated with Frey for many years on the effects of soil warming and nitrogen on the biogeochemistry of soil carbon in the Harvard Forest.

She says the research is unique because it includes both individual and combined treatments that represent combined impacts to temperate forests.

“Because of the advanced analytical capabilities in my laboratory and the Environmental NMR Centre at U of T Scarborough, we can uniquely decipher how multiple stressors alter the chemistry and potential long-term stability of soil organic matter at the molecular-level.”

Despite the research being conducted in Harvard Forest, Simpson says that soil warming has been shown to cause carbon loss worldwide. Excess nitrogen has also been found to suppress the microorganisms that keep forests healthy, even in forests that are rich in nutrients.

“We found that the way in which carbon flows within the soil biogeochemical cycle cannot be predicted from one stressor alone,” says Simpson, who is Canada Research Chair in Integrative Molecular Biogeochemistry. “It is likely that these observations may occur in other forests too.”

When it comes to future climate change research, Simpson says that there is much more work to be done.

“We need more observational data because climate change’s impacts on ecosystems are complex and difficult to predict due to the diversity of ecosystem properties,” she says. “These ecosystems are influenced by more than one stressor, but we lack data to adequately predict the impacts.”

Simpson adds there is no single way to solve climate change in part because we don’t yet understand all of its effects.

She says that collaboration between researchers is critical.

“Each expert can contribute data that can then be integrated into a more comprehensive assessment of how ecosystems are responding to stressors.”

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Ammara Khan

Microfluidic device reveals how tumour shapes can predict cancer aggressiveness

rahul.kalvapalle — Wed, 18 Dec 2024 15:46:03 +0000

Microfluidic device reveals how tumour shapes can predict cancer aggressiveness

rahul.kalvapalle Wed, 12/18/2024 - 10:46

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Associate Professor Edmond Young of U of T's Faculty of Applied Science & Engineering (left) and PhD alum Sina Kheiri co-developed the Recoverable-Spheroid-on-a-Chip with Unrestricted External Shape – or "ReSCUE" – platform (photos courtesy of Edmond Young and Sina Kheiri)

Safa Jinje

Topic

Breaking Research

department of mechanical and industrial engineering

Institute of Biomedical Engineering

Faculty of Applied Science & Engineering

Subheadline

The platform, developed by U of T researchers, allows for unprecedented control and manipulation of tumour shapes

Researchers in the ��߲ݴ�ý’s Faculty of Applied Science & Engineering have designed a microfluidic platform that can be used to predict cancer cell behaviour and aggressiveness, opening up new avenues for personalized and targeted cancer treatment.

The Recoverable-Spheroid-on-a-Chip with Unrestricted External Shape (ReSCUE) platform, developed by a team led by Edmond Young, an associate professor in the department of mechanical and industrial engineering, gives researchers the ability to recover and release tumoroids – tumour cells derived from patients – to perform downstream analysis and characterization.

This allows for unprecedented control and manipulation of tumour shapes, a largely unexplored area in cancer research.

“While there are several platforms for in vitro modelling of spheroids – three-dimensional aggregates of cells that can mimic tissues and mini tumours – a challenge in the cancer research field has been the inability to control the shape, recovery and location of these cancer organoids,” says Sina Kheiri, a PhD alum and co-lead author of the study, which was published in Advanced Materials.

“So, researchers end up with these tumours-on-a-chip that can’t be easily characterized because they are stuck on the device and can only be observed through optical microscopy.”

The platform also enables researchers to grow cancer organoids in different shapes. This is important, Kheiri says, because much of the current research on cancer cell in vitro modelling is focused on spherical tumours, but tumours in a body can take many different shapes.

“In many invasive cancers, the tumour shape is not spherical. For example, in a recent study of 85 patients with breast cancer, only 20 per cent of tumours were spherical,” he says. “If modelling studies are limited to spherical tumour shapes, then we are not looking at the full parametric space and scale of tumours that are seen in real life. We are only looking at a small portion of the whole answer to understand cancer cell behaviour.”

Kheiri’s PhD research was co-supervised by Young and Eugenia Kumacheva, a professor in the Faculty of Arts & Science’s department of chemistry who is cross-appointed to the Institute of Biomedical Engineering. Kumacheva’s lab developed a biomimetic hydrogel that is used as a scaffold in the multi-layer ReSCUE platform, allowing the patient-derived cancer cells to grow and organize the way they would inside human tissue.

The platform was developed in collaboration with David Cescon, a clinician scientist and breast medical oncologist at Princess Margaret Cancer Centre and associate professor in the Institute of Medical Science at the Temerty Faculty of Medicine. Cescon’s team provided access to the cancer cells that were used to form breast cancer organoids.

This image shows culture, release and transfer of tumoroids from the ReSCUE platform, as well as the released breast cancer disk-, rod-, and U-shaped tumoroids cultured in biomimetic hydrogel over zero, seven, 14 and 21 days (image courtesy of Young Lab)

The idea that tumour shapes determine cancer cell behaviour was a serendipitous discovery for Kheiri: while optimizing and developing the microfluidic platform, he discovered that some of the patient-derived tumoroids were forming positive curvatures because of the shape of the microwell. 

“I was playing with the aspect ratio of the microwells and observed that when the wells had a more rod-like or elongated shape, rather than a circular or disc shape, the tissues formed cellular strands at the regions with positive curvature,” he says. “I didn’t see that in tumoroids from the same cancer-cell sample that formed a spherical shape.

"So, we started to make different shapes and analyze the effects of shape or curvature on cancer behaviour."

The team looked at disk-, rod- and U-shaped tumoroids; they found higher cell activity and higher proliferation at the positive curvatures – where the tumour shape is convex and outward curving.

This could mean that the growth of cells in these areas is more invasive compared to areas of the tumour that have a flat curvature.

“Understanding the relationship between tumour shape and cell behaviour is important for predicting tumour aggressiveness and planning appropriate treatment strategies, such as targeted radiation therapy or drug delivery,” says Kheiri. “We want to open this door and give researchers a platform that they can use to study how different tumour shapes respond in anti-cancer drug treatment, in radiotherapy and chemotherapy.”

Now a postdoctoral researcher at the Massachusetts Institute of Technology (MIT), Kheiri continues to provide support to the Young lab on development of the ReSCUE platform. The researchers recently submitted a U.S. patent and are looking to build on their results.

“We hope that these uniquely shaped mini tumours can help biologists and cancer researchers better understand the biology of cancer cells and how they respond to drugs,” says Young.

“We’re going to add even more complex features, such as surrounding vasculature. The more control we have over the features we can include in our models, the more realistic they become, and the more accurate our drug testing will be.”

Should you eat soy after menopause? U of T researchers dispel myth about soy and cancer

rahul.kalvapalle — Wed, 04 Dec 2024 00:53:18 +0000

Should you eat soy after menopause? U of T researchers dispel myth about soy and cancer

rahul.kalvapalle Tue, 12/03/2024 - 19:53

Cutline

A study led by researchers at the Temerty Faculty of Medicine's department of nutritional sciences found that soy isoflavones – estrogen-like compounds – had no effect on key markers of estrogen-related cancers (photo by Yagi Studio/Getty Images)

Betty Zou

Topic

Breaking Research

Temerty Faculty of Medicine

Unity Health

Nutritional Sciences

St. Michael's Hospital

Subheadline

“We hope our study will help people feel more comfortable including soy foods in their diet"

A study led by experts at the ��߲ݴ�ý's Temerty Faculty of Medicine is providing reassuring evidence on consumption of soy foods during postmenopause.

In a systematic review and meta-analysis of 40 trials in over 3,000 participants, U of T researchers gathered results on the effects of soy isoflavones – estrogen-like compounds naturally found in plants – on biological outcomes related to risk of endometrial and other female-related cancers.

Their results, published in Advances in Nutrition, found that isoflavones had no effect on key markers of estrogen-related cancers, supporting the safety of soy as a food as well as potential therapy.

“The risk of cardiovascular disease increases substantially as women* go through menopause, so soy can offer dual benefits during this particular phase of life,” says the study’s senior author Laura Chiavaroli, an assistant professor in Temerty's department of nutritional sciences and affiliate scientist at the Li Ka Shing Knowledge Institute at St. Michael’s Hospital, Unity Health Toronto.

Assistant Professor Laura Chiavaroli (left) and PhD student Gabrielle Viscardi (supplied images)

Yet, Chiavaroli notes many people are hesitant to eat soy foods because they contain isoflavones, which have a similar structure to estrogen. In animal studies, large doses of isoflavones have been linked to a higher risk of cancer.

“Something we hear very often is that people have a lot of concern about consuming soy because there are so many conflicting messages out there,” says Gabrielle Viscardi, a second-year PhD student in the department of nutritional sciences and the study’s lead author.

This is despite the fact that several health advocacy groups, including the Canadian Cardiovascular Society, already recommend soy foods as part of a healthy diet. Health Canada and the U.S. Food and Drug Administration have both recognized soy – a high-quality and complete source of protein – as effective in reducing the risk of heart disease

Soy foods have also been shown to alleviate hot flashes associated with menopause, which affect many women and impact their quality of life.

The trials considered for the U of T study followed postmenopausal women from around the world who had consumed either soy isoflavones or a non-isoflavone control for at least three months.

The researchers concluded that consumption of soy isoflavones did not affect the four key estrogen-related markers, namely: thickness of uterus lining, vaginal maturation index (a measure of estrogen status) and levels of circulating estrogen and follicle-stimulating hormone.

Their findings support the idea that soy isoflavones behave differently from human estrogen, particularly when it comes to cancers that depend on estrogen to develop. “We have estrogen receptors throughout our bodies but, contrary to the hormone estrogen, isoflavones from soy don’t bind to all the estrogen receptors equally,” says Viscardi, who is also a registered dietitian. “That’s why we see a beneficial effect on the cardiovascular system and no effect on the female reproductive system.”

This difference in biological activity explains why soy isoflavones have been considered as a possible alternative to hormone replacement therapy (HRT), which is used to treat menopause symptoms by replacing the estrogen that the body stops producing during this period.

Chiavaroli notes some people don’t want to take HRTs and are seeking alternative options.

Further, HRTs may also not be a good option for people at an increased risk of estrogen-sensitive cancers like breast cancer, as well as those with a history of heart disease and stroke. For these individuals, consuming soy foods as part of a balanced diet could help manage their menopausal symptoms while also reducing the risk of cardiovascular disease.

Chiavaroli says the study's findings also align with Health Canada’s dietary guidelines that encourage people to choose plant-based proteins more often, a move that would also convey benefits for the environment.

“We hope our study will help people feel more comfortable including soy foods in their diet without being concerned that it’s going to increase their risk of estrogen-dependent cancer,” says Chiavaroli.

The study was funded by the United Soybean Board (U.S. Department of Agriculture) and the Canadian Institutes of Health Research through the Canada-wide Human Nutrition Trialists’ Network.

* Although menopause is sex-specific, the study retains use of the term "women" as it is used conventionally in studies and guidelines on menopause

PhD student's radiopharmaceutical to play key role in clinical trial for lung cancer treatment

rahul.kalvapalle — Tue, 26 Nov 2024 20:59:25 +0000

PhD student's radiopharmaceutical to play key role in clinical trial for lung cancer treatment

rahul.kalvapalle Tue, 11/26/2024 - 15:59

Cutline

Stephanie Borlase developed a radiopharmaceutical, which will be used during a clinical trial at Sunnybrook Health Sciences Centre, to track delivery of immunotherapy drugs across the blood-brain barrier (photo by Dana Thompson)

Eileen Hoftyzer

Topic

Breaking Research

Sunnybrook Health Sciences Centre

Graduate Students

Leslie Dan Faculty of Pharmacy

Subheadline

The compound developed by U of T's Stephanie Borlase will be used to track delivery of immunotherapy drugs to metastases in the brain

A radiopharmaceutical developed by ��߲ݴ�ý PhD student Stephanie Borlase is poised to play a key role in a clinical trial that could inform improvements to lung cancer treatment.

The trial at Sunnybrook Health Sciences Centre, planned for 2025, will test whether ultrasound can disrupt the blood-brain barrier and increase uptake of immunotherapy into brain metastases – tumours caused by cancer cells spreading to the brain from elsewhere in the body.

Although immunotherapy has shown potential as a treatment for lung cancer, it is not able to cross the blood-brain barrier. Borlase’s radiopharmaceutical, which she developed as part of her doctoral research at the Leslie Dan Faculty of Pharmacy, will be used to track delivery of immunotherapy drugs to brain metastases with a PET (positron emission tomography) scan.

“This project provides me with the opportunity to learn different aspects of research and be on the forefront of patient treatments,” says Borlase. “It is such an amazing opportunity to be able to see what is happening in the hospital with current patients and clinical trials and know that my research is actually getting to patients.”

Borlase completed her undergraduate and master’s degrees at the University of Manitoba, before seeking out a PhD program where she could conduct research that could potentially be translated into therapies for patients with hard-to-treat cancers.

In 2022, she began her PhD with Professor Raymond Reilly, director of the Centre for Pharmaceutical Oncology (CPO), whose research focuses on developing radiopharmaceuticals to image and treat cancer.

By attaching radioactive isotopes to highly targeted agents, radiopharmaceuticals allow clinicians to image tumours through scans and deliver therapeutic doses of radiation directly to the tumour.

Borlase has been working towards pairing the immunotherapy drug pembrolizumab (also known by the brand name Keytruda) with a radioactive isotope that can be imaged by PET – resulting in a radiopharmaceutical that could allow physicians to determine whether the therapy enters the brain and concentrates better in tumours after the application of focused ultrasound.

For the first two years of her PhD, Borlase worked in the CPO’s Good Manufacturing Practices facility to prepare the new radiopharmaceutical for clinical trials, optimizing and formulating the drug in a quality suitable for use in humans, and testing it in pre-clinical models.

Reilly says that this is an exceptional experience for a graduate student. “One of the greatest impacts and rewards of pharmaceutical sciences research is to see your work advanced to a clinical trial to make a difference in patient outcomes, which Stephanie has this wonderful opportunity to do,” he says.

“Not only is she developing the radiopharmaceutical, but she will be working closely with the oncologists and imaging specialists to design and conduct the trial and will get first-hand experience in seeing the results of her PhD research in the PET images of the patients in the trial.”

The trial follows on the heels of another study in which clinicians and scientists at Sunnybrook used a radiopharmaceutical provided by Reilly’s team to track the delivery of a breast cancer drug to brain metastases, resulting in the first evidence that the technique improved uptake of the drug.

For her part, Borlase says she hopes the trial will lead to better therapies for a form of cancer that is notoriously difficult to treat.

“I always hope that researchers can develop new treatments for cancer because it is such a terrible disease that is never going to disappear. Even if we cannot completely cure the brain metastases, we can work to prolong survival to give these individuals more time with their families and friends,” says Borlase, who recently received a Research Training Award from the Canadian Cancer Society and Brain Canada Foundation.

“It's such a rare opportunity for PhD students to be able to work with clinician-scientists or oncologists and actually see their research translate into a clinical setting, so the fact that I am able to do this is incredible.”