Cardiac

Injectable tissue patch could help repair damaged organs: 91�Թ� research

ullahnor — Mon, 14 Aug 2017 17:33:10 +0000

Injectable tissue patch could help repair damaged organs: 91�Թ� research

ullahnor Mon, 08/14/2017 - 13:33

Cutline

The flexible tissue scaffold, shown here emerging from a glass pipette with a tip one millimetre wide, unfolds itself after injection into the body. This could enable surgeons to use minimally invasive techniques (photo by Miles Montgomery and Rick Lu)

Tyler Irving

Author legacy

Tyler Irving

Topic

Breaking Research

Cardiac

IBBME

Faculty of Applied Science & Engineering

Tissue Engineering

Subheadline

New biomaterial developed by 91�Թ� engineering researchers could be delivered through minimally invasive surgery

A team of 91�Թ� engineering researchers is mending broken hearts with an expanding tissue bandage a little smaller than a postage stamp.

Repairing heart tissue destroyed by a heart attack or medical condition with regenerative cells or tissues usually requires invasive open-heart surgery. But now biomedical engineering Professor Milica Radisic and her colleagues have developed a technique that lets them use a small needle to inject a repair patch, without the need to open up the chest cavity.

Radisic’s team are experts in using polymer scaffolds to grow realistic 3D slices of human tissue in the lab. One of their creations, AngioChip, is a tiny patch of heart tissue with its own blood vessels – the heart cells even beat with a regular rhythm. Another one of their innovations snaps together like sheets of Velcro™.

Such lab-grown tissues are already being used to test potential drug candidates for side-effects, but the long-term goal is to implant them back into the body to repair damage.

“If an implant requires open-heart surgery, it’s not going to be widely available to patients,” says Radisic.

She says that after a myocardial infarction – a heart attack – the heart’s function is reduced so much that invasive procedures like open-heart surgery usually pose more risks than potential benefits.

“It’s just too dangerous,” she says.

From left to right, PhD candidate Miles Montgomery discusses his research with MP Peter Van Loan, Professor Milica Radisic and then Minister of State for Science and Technology Ed Holder, during a tour of 91�Թ�’s Institute for Biomaterials & Biomedical Engineering in 2014 (photo by Johnny Guatto)

Miles Montgomery, a PhD candidate in Radisic’s lab, has spent nearly three years developing a patch that could be injected, rather than implanted.

“At the beginning, it was a real challenge,” he says. “There was no template to base my design on, and nothing I tried was working. But I took these failures as an indication that I was working on a problem worth solving.”

After dozens of attempts, Montgomery found a design that matched the mechanical properties of the target tissue and had the required shape-memory behaviour: as it emerges from the needle, the patch unfolds itself into a bandage-like shape.

“The shape-memory effect is based on physical properties, not chemical ones,” says Radisic.

This means that the unfolding process doesn’t require additional injections and won’t be affected by the local conditions within the body.

The next step involved seeding the patch with real heart cells. After letting them grow for a few days, researchers injected the patch into rats and pigs. Not only did the injected patch unfold to nearly the same size as a patch implanted by more invasive methods, the heart cells survived the procedure well.

“When we saw that the lab-grown cardiac tissue was functional and not affected by the injection process, that was very exciting,” says Montgomery. “Heart cells are extremely sensitive, so if we can do it with them, we can likely do it with other tissues as well.”

The scaffold is built out of the same biocompatible, biodegradable polymer used in the team’s previous creations. Over time, the scaffold will naturally break down, leaving behind the new tissue.

The team also showed that injecting the patch into rat hearts can improve cardiac function after a heart attack: damaged ventricles pumped more blood than they did without the patch.

“It can’t restore the heart back to full health, but if it could be done in a human, we think it would significantly improve quality of life,” says Radisic.

There is still a long way to go before the material is ready for clinical trials. Radisic and her team are collaborating with researchers at the Hospital for Sick Children to assess the long-term stability of the patches, as well as whether the improved cardiac function can be maintained.

They have also applied for patents on the invention and are exploring the use of the patch in other organs, such as the liver.

“You could customize this platform, adding growth factors or other drugs that would encourage tissue regeneration,” says Radisic. “I think this is one of the coolest things we’ve done.”

The research is published in Nature Materials. The project was supported by the Canadian Institutes of Health Research, National Sciences and Engineering Research Council of Canada, the 91�Թ�, the Heart and Stroke Foundation, the Canada Foundation for Innovation, the Ontario Institute for Regenerative Medicine and the Ontario Research Fund.

91�Թ� inventor-entrepreneur honoured with Governor General’s Innovation Award

ullahnor — Fri, 05 May 2017 13:50:13 +0000

91�Թ� inventor-entrepreneur honoured with Governor General’s Innovation Award

ullahnor Fri, 05/05/2017 - 09:50

Cutline

Professor Paul Santerre (left) with PhD candidates Yasaman Delaviz (centre) and Meghan Wright (right) in his lab. He is among the six recipients of the 2017 Governor General’s Innovation Awards (photo by Neil Ta)

Erin Vollick

Author legacy

Erin Vollick

Topic

Breaking Research

Faculty of Applied Science & Engineering

Subheadline

The award recognizes outstanding Canadians who contribute to the country’s success and inspire the next generation

The molecules he works with may be small, but Professor Paul Santerre is using them to solve some of the world's biggest and most pressing medical challenges.

One of Santerre’s most successful inventions is Endexo™, a surface-modifying material that can be applied to medical tubing to prevent blood from sticking and clotting, one of the major reasons for catheter failure. His 91�Թ� startup Interface Biologics (IBI) has three distinct molecule-based technology platforms, which can be applied to hundreds of different products and are estimated to be worth billions. He is a leader in engineering smart scaffolds to repair heart tissue.

Today, Santerre is one of six awardees being honoured with the 2017 Governor General’s Innovation Award. He'll will be recognized at a special ceremony at Rideau Hall on May 23.

One of the world’s leading biomaterials researchers, Santerre is a professor in the Faculty of Dentistry and the Institute of Biomaterials & Biomedical Engineering at the Faculty of Applied Science & Engineering. He is also a lead researcher at the Translational Biology and Engineering Program, part of the Ted Rogers Centre for Heart Research.

“We’d like to congratulate Professor Santerre for winning the 91�Թ�’s first-ever Governor General’s Innovation Award,” said Vivek Goel, the university’s vice-president of research and innovation. “This is a wonderful recognition of his cutting-edge research and his efforts to bring those innovations to market, enabling Canadians and others to lead healthier lives.”

For example, with Endexo, the flexible material used in medical tubing, it avoids the need for blood-thinning drugs. Santerre commercialized Endexo and other surface-modifying molecules through Interface Biologics, now in its sixteenth year.

Useful for far more than medical devices, Santerre’s surface-modifying technologies are designed to work in harmony with the body’s natural repair processes.

With a collaborative team at the Ted Rogers Centre for Heart Research, Santerre was recently awarded a three-year, $600,000 Collaborative Health Research Project grant to continue to develop a biodegradable cardiac patch. Adapted from the same basic concepts underlying his surface modifying molecules, the patch persuades damaged cardiac tissues to re-form while it slowly degrades into materials that the body can easily flush. Importantly, the materials in the patch will calm immune responses – preventing fibrotic scar tissue from forming on the heart – and reduce the risk of heart failure.

Yet another application of the technology could revolutionize how complicated craniofacial fractures are repaired. Rather than surgically inserting plates and metal screws into the head and face, a ceramic-based “bone tape” that promotes bone growth could be applied to fracture sites. Surgeons will be able to apply this ceramic-based bone tape directly to fractures without the added need for glue, screws or pins. Like with the heart patch, the materials are designed to calm immune responses and slowly biodegrade as new bone forms, ensuring better cosmetic outcomes as well as faster healing times.

“This is invention spinning off invention,” Santerre said, crediting his success as a researcher in part to the collaborative and cross-disciplinary culture being fostered by the university and its partnerships, such as that formed between Sick Kids, UHN, and 91�Թ� to create the Ted Rogers Centre for Heart Research, where Santerre’s lab is located. “It’s truly amazing to watch. When visitors come here they can’t believe its collaborative nature,” he added.

In addition to his own growing company, Santerre has been guiding his students in commercializing their discoveries through start-up companies, such as the recently founded Polumiros, which is developing its first product for market: a non-inflammatory, biodegradable “tissue filler” for replacing breast tissue after breast cancer surgeries. Santerre also helps to mentor more than 70 trainee-based startup companies across 91�Թ� in his role as co-director of the Faculty of Medicine’s Health Innovation Hub (H2i).

For Santerre, the H2i Hub and the other nine accelerators presently active on campus points to a seismic shift in Canada’s intellectual institutions, as the university aligns itself with entrepreneurship. It’s a move he views as critical to Canada’s economic development and its ability to compete in the global health care and innovation industries.

Learn more about entrepreneurship and startups at 91�Թ�

Health care represents the world’s largest and fastest growing economic market, contributing as much as $1 out of every $5 to the GDP in North America. But while Canada – Toronto in particular –is poised to become a world leader in this growth industry, Santerre points out that this can’t be accomplished without major investment from Canadian universities.

“The argument that academia should steer away from contributing to applied knowledge with an entrepreneurial perspective is no longer as tenable as it once was,” said Santerre, who was awarded the NSERC Synergy Award for Innovation in 2012, the Ernest C. Manning Innovation Award’s Principal Award in 2014, and 91�Թ�’s prestigious Connaught Innovation Award earlier this year.

“I extend to Paul my most sincere congratulations on this well-deserved honour,” said Daniel Haas, dean of the Faculty of Dentistry. “This award is a recognition of Paul’s ingenuity and drive to bring the 91�Թ�, and by extension, Canada, to the forefront of the innovation industries through its applied and clinical research, and a direct reflection of his enormous impact.”

“Professor Santerre’s outstanding research and inventions are a brilliant example of how multidisciplinary collaboration can address complex challenges and help people live longer, healthier lives,” said Cristina Amon, aean of the Faculty of Applied Science & Engineering. “On behalf of the Faculty, my warmest congratulations to him on this richly deserved and prestigious recognition.”

Now in its second year, the Governor General Innovation Awards program recognizes “trailblazers and creators” who contribute to a culture of innovation in Canada.

Coffee shops, 24-hour ATMs are the best locations for life-saving AEDs, 91�Թ� research shows

ullahnor — Mon, 20 Mar 2017 20:57:33 +0000

Coffee shops, 24-hour ATMs are the best locations for life-saving AEDs, 91�Թ� research shows

ullahnor Mon, 03/20/2017 - 16:57

Cutline

Timothy Chan (left) and Christopher Sun (right) studied data on cardiac arrest locations in Toronto to determine a list of “Top 10” businesses where placing automated external defibrillators would save lives (photo by Marit Mitchell)

Liz Do

Author legacy

Liz Do

Topic

Subheadline

91�Թ� Engineering team creates list of top 10 businesses where placing automatic external defibrillators would save lives

ATMs and coffee shops such as Tim Hortons, Starbucks and Second Cup make ideal locations for placing automated external defibrillators (AEDs), says a new study led by 91�Թ� Engineering Professor Timothy Chan and PhD candidate Christopher Sun, in collaboration with St. Michael’s Hospital.

When a patient suffers cardiac arrest, every second counts — the chances of survival decrease by 10 per cent each minute. Responding quickly can be the difference between life and death, and that means having immediate access to a nearby AED.

“Previous research on AED placements had focused on broadly defined location categories, like shopping malls or office buildings,” said Sun. “But these categories generalize many individual businesses, which have different hours, activities performed, and other unique properties that meant we could be missing critical insight on which locations are really high risk. So we wanted to get more specific: which individual locations or businesses could AEDs be placed to make sure they are accessible to the largest number of people throughout the day.”

Their findings are already making headlines.

See the CBC story

See the Toronto Star story

See the CNN story

Their new study, published today in the American Heart Association journal Circulation, looked at where cardiac arrests occur, to find locations where AEDs would be most valuable.

Map of the facilities of the Top 5 ranked businesses in terms of actual coverage in all of Toronto (image courtesy of Sun & Chan)

First, the researchers identified all businesses with 20 or more locations in Toronto – facilities such as Tim Hortons coffee shops or libraries that would make good candidates to place AEDs in.

Then they looked at the number of cardiac arrests that occurred within 100 metres of each location, during the businesses’ operating hours. Using this data, Chan and Sun calculated the “spatiotemporal cardiac arrest coverage” provided by each location or business. The specific locations and businesses were then ranked to determine a “Top 10” list of prime spots to place AEDs.

“We found that coffee shops and ATMs ranked highly across several related metrics, and that those rankings were stable over the years,” said Chan, who is the director of the Centre for Healthcare Engineering at U of T and a Canada Research Chair in Novel Optimization and Analytics in Health.

“What we found really interesting is that ATMs, as opposed to the more traditional businesses, are often standalone or outdoors, and are often available 24/7. They’re also universally recognizable and already have an electronic and security infrastructure – hypothetically, if we were to have AEDs paired with ATMs, it would be very beneficial,” said Sun.

Three coffee shop chains – Tim Hortons, Starbucks and Second Cup – as well as five of the big banks with many ATM locations, including RBC and Scotiabank, made the top 10. Tim Hortons was ranked first, with more than 300 shops in Toronto. These locations alone would have provided AED coverage for more than 200 out-of-hospital cardiac arrests over an eight-year period.

The researchers hope this new study could soon lead to AEDs placed in these optimal locations.

“Health organizations, foundations and policymakers aiming to develop public access defibrillator programs could use our rankings to identify promising businesses to develop partnerships for AED deployment,” added Chan.

Chan’s lab has a number of ongoing research projects on AED placements, including using drones to deliver AEDs, and optimizing AED placements in high-rise buildings.

“Ultimately, we want to get AEDs in the right locations so they are accessible when needed most,” said Chan.

Sun says cardiac arrests are unique because in the early stages they can be treated as effectively by untrained responders as by paramedics.

“That’s why finding out the best placements for AEDs is so important,” said Sun. “We have the opportunity to save lives based on our level of preparation and organization.”

Top 10 locations for AEDs based on coverage

Tim Hortons
RBC ATMs
Subway restaurants
Scotiabank ATMs
CIBC ATMs
TD ATMs
Green P public parking lots
Starbucks
BMO ATMs
Second Cup

Engineered smart scaffolds at 91�Թ� could help repair damaged hearts and muscles

ullahnor — Fri, 27 Jan 2017 17:07:36 +0000

Engineered smart scaffolds at 91�Թ� could help repair damaged hearts and muscles

ullahnor Fri, 01/27/2017 - 12:07

Cutline

Professor Paul Santerre (left) and PhD candidates Yasaman Delaviz (middle) and Meghan Wright (right) are developing implantable materials that can activate the body’s innate response to damage, including heart attacks (photo by Neil Ta)

Tyler Irving

Author legacy

Tyler Irving

Topic

Breaking Research

IBBME

Faculty of Applied Science & Engineering

Cardiac

Muscle

A scar on your skin may be insignificant, but a scar on your heart could be deadly. Scar tissue in muscle can impair its function and lead to long-term damage like limping or heart failure.

Leading-edge research from the 91�Թ� is addressing this challenge. Two multidisciplinary teams consisting of engineers, biologists, physicians and other medical experts are designing implantable materials that activate the body’s innate response to injury, leading to more complete healing and preventing harmful complications.

These projects are made possible through Medicine by Design and the Translational Biology and Engineering Program (TBEP), two major collaborative research initiatives led by 91�Թ� Engineering faculty members that have been created in the last three years. Medicine by Design and TBEP unite researchers from 91�Թ�'s Faculty of Applied Science & Engineering and many other faculties across 91�Թ�, as well as external partners at hospitals and research institutions.

Learn more about Medicine by Design

Learn more about the Translational Biology and Engineering Program (TBEP)

Repairing heart tissue

After a heart attack, the body’s immune system clears away dead cells and stimulates the remaining tissue to repair itself, but the fix is rarely seamless.

“The repair process leaves scars behind,” says Paul Santerre, a professor at IBBME who is one of the principal investigators at TBEP. “After years of running inefficiently because of those scars, gradually the walls of the heart begin to weaken, leading to heart failure.”

Santerre and his team have taken a form of polyurethane – a type of plastic – and chemically formulated new monomer configurations, enabling the material to instigate a repair response by the immune system.

“If you get a splinter in your finger, your body will recognize that as something foreign that needs to be eliminated,” says Santerre. “Our degradable polymers bind to proteins that are signals for the immune system, telling it not to go into an inflammatory state, but rather go into a repair state.”

The team recently received funding to develop a cardiac patch that could be used following a heart attack. “The ultimate goal would be to build a construct out of our material, seed it with a patient’s own stem cells in the lab, grow the tissue within a couple of weeks and then insert that as a patch to coach local repair.”

The patch could lead to more complete healing, minimizing long-term damage.

Santerre is also collaborating with fellow TBEP members Craig Simmons and Hai-Ling Margaret Cheng on other applications of the material, such as generating replacement heart valves or regrowing small blood vessels in the heart.

“To have leading experts in biomechanics, medical imaging and genomics all within seconds of my office, that’s really going to accelerate this work.”

Accelerating muscle recovery

After a traumatic injury, muscles can become swollen to the point where they constrict blood flow. This condition, known as compartment syndrome, can lead to death of muscle tissue.

The standard treatment is to cut open the affected area to relieve the pressure but recovery can take months. Now, a team of biomedical engineers, biologists and physicians aims to speed up the process by activating a type of stem cell found in muscle tissue called satellite cells.

“Satellite cells are essential for repairing muscle,” says Penney Gilbert, assistant professor at 91�Թ�'s Institute of Biomaterials & Biomedical Engineering (IBBME), one of the researchers on the project. “We need them to wake up, make copies of themselves, fuse and fix the broken muscle fibres to repair the damage.”

Gilbert and her team study the signaling proteins produced by nearby cells that activate satellite cells. They hope that by mimicking these molecules, they can enhance the body’s natural response to trauma.

“We could synthesize all those different proteins and deliver them to the area, but it would be very cumbersome,” says Michael Sefton, University Professor in chemical engineering at IBBME, who is a lead researcher on the collaboration.

Instead, the team aims for a simpler approach. They want to create an implantable material that incorporates the effect of the signaling proteins into its chemical structure. This more elegant solution would still activate the satellite cells while ensuring that the response stays localized and lasts throughout recovery.

“We want a device, not a drug,” says Sefton.

The project is among 20 collaborations funded through Medicine by Design. Sefton and Gilbert are collaborating with 91�Թ� Engineering Associate Professor Alison McGuigan as well as a number of medical researchers at Toronto-area hospitals.

“We have expertise along the entire pathway from the fundamental biology of the satellite cells to the creation of a bio-active material,” says Sefton. “Everyone is contributing to an integrated whole.”

After a heart attack, the body’s immune system clears away dead cells and stimulates the remaining tissue to repair itself, but the fix is rarely seamless.

The patch could lead to more complete healing, minimizing long-term damage.

“To have leading experts in biomechanics, medical imaging and genomics all within seconds of my office, that’s really going to accelerate this work.”

91�Թ� researchers' drone-delivered AEDs offer novel approach to saving lives at home

ullahnor — Mon, 14 Nov 2016 17:18:22 +0000

91�Թ� researchers' drone-delivered AEDs offer novel approach to saving lives at home

ullahnor Mon, 11/14/2016 - 12:18

Cutline

91�Թ�'s Timothy Chan (left), Angela Schoellig and Justin Boutilier (right) are part of a research team trying to use drones to deliver AEDs (photo by Liz Do)

Liz Do

Author legacy

Liz Do

Topic

City & Culture

Faculty of Applied Science & Engineering

Subheadline

Drone delivery could shave crucial minutes off the median ambulance response times in both rural and urban regions

When a person goes into cardiac arrest, every passing minute hurts their chances of survival. Now, a group of 91�Թ� researchers want to use drones to deliver life-saving automatic external defibrillators (AEDs) rapidly and directly to homes.

Justin Boutilier, a PhD candidate in the Faculty of Applied Science & Engineering, envisions a future in which a bystander or family member who witnesses a cardiac arrest can call 911, and within minutes, an AED is flown to their doorstep or balcony to be administered – before the paramedics arrive.

Boutilier is working under Associate Professor Timothy Chan, director of 91�Թ�'s Centre for Healthcare Engineering, in collaboration with Assistant Professor Angela Schoellig and researchers from St. Michael’s Hospital's Rescu program, in order to turn the futuristic idea into a life-saving reality.

This project comes on the heels of research by Chan’s lab on cardiac arrests that occur outside of hospitals, and the lack of accessible AEDs in public locations during non-business hours. Boutilier is now focusing on reducing deaths from cardiac arrests that occur at home.

About 85 per cent of out-of-hospital cardiac arrests in Southern Ontario take place within a private residence.

“For those arrests, the public AEDs are not useful because it’s hard to get to them in time. It’s also not cost effective to put AEDs everywhere in the suburbs,” explained Boutilier.

Therefore, the survival rates are not good.

“Not only is the survival rate of private-location cardiac arrests low, the response times are also slower than public locations,” said Chan. “So we thought, we need to come up with something completely new.”

Chan and Dr. Steve Brooks, an emergency physician at Kingston General Hospital and frequent collaborator at Rescu, found a video of a prototype AED drone designed at Delft University in the Netherlands. A PhD student had developed the prototype, complete with a camera and microphone, which weighed only four kilograms and travelled 100 kilometres per hour.

“To us, the idea of using a drone to deliver an AED to private location cardiac arrests seemed like a no-brainer,” said Chan.

Of the many benefits to AED drone delivery: “You don’t have to worry about traffic. You could get the AED there faster than paramedics so the bystander can start treatment as early as possible. And that’s very important. Every minute that goes by, the chance of survival decreases,” said Chan.

To determine where drones should be stationed and how many are needed to serve a given population, Boutilier obtained historical cardiac arrest data from eight regions in Southern Ontario, including dense urban cities and sparse rural communities.

“We conducted our analysis by imagining that this technology was implemented five years ago and asking, what would the next five years have looked like?” Boutilier explained.

What they found was that they were able to shave several minutes off the median ambulance response times in both rural and urban regions, and drones could arrive ahead of ambulances more than 90 per cent of the time.

“The one challenging thing is that it’s hard to know the number of lives we could have saved, which is what we’re looking at now,” said Boutilier.

Regulatory restrictions present another challenge to implementation – aviation, including drone flights, is strictly regulated by Transport Canada. Current rules stipulate that users are prohibited from flying drones out of their line of sight.

Schoellig, the associate director of the Centre for Aerial Robotics Research and Education (CARRE) at U of T, believes these restrictive regulations won’t last for long. “It is a matter of proving safety and reliability of this new technology to the regulators. This will require more technological breakthroughs – for example, giving drones the ability to detect obstacles.

But drone technology has developed very quickly in the last five to 10 years,” she explained.

“Google and Amazon are already working on implementing delivery drones and have been lobbying the government to ease these regulations,” added Boutilier. “So if the government allows the drone delivery of commercial products, they would allow the delivery of AEDs, which is a life-saving matter.”

This past weekend, Boutilier and Chan presented their research at the American Heart Association Resuscitation Science Symposium in New Orleans, where Boutilier says he was excited to see the reactions from attendees.

“Depending on whom you talk to, the response can be very different. When I talk to medical professionals, some say, ‘That’s too futuristic,’ but when I talk to tech people their reaction is often, ‘This technology has been around for the last few years. We could do this tomorrow.’

“We’re trying to shake things up a bit within the field of health care, and change the way people are thinking about how we solve problems.”

In the near future, Boutilier hopes to pilot the project in Muskoka, a region that has a high rate of bystander cardiopulmonary resuscitation (CPR), and the slowest ambulance response time of all the regions they’ve gathered data from.

“I think the technology is there. I think the challenge is in the details of how to make this work,” said Chan. “It’s working through government regulations, coordinating with Emergency Medical Services, and making sure the public is behind this, that they have awareness of drones and its various purposes.

“But ultimately, it’s an idea that I think can really make a huge leap forward in our ability to get defibrillators to patients. I think within five to 10 years, drone deliveries will be a reality.”

At the intersection of dance and nitroglycerin

sgupta — Fri, 04 Dec 2015 02:32:51 +0000

At the intersection of dance and nitroglycerin sgupta Thu, 12/03/2015 - 21:32

Cutline

“I feel happy after I dance,” Kangbin Zhou says, “and that happiness helps me overcome despair or frustration after a difficult day in the lab.”

Erin Howe

Author legacy

Erin Howe

Subheadline

PhD student leads on the dance floor and in researching why angina treatment works

By day, Kangbin Zhou researches what makes nitroglycerin – a common treatment for chest pain also known as angina – effective.

By night, the fourth-year pharmacology and toxicology PhD student can be found tearing up the dance floor as the founder and instructor of a 91�Թ� urban dance club.

Zhou is the first recipient of the Dr. Malle Jurima-Romet Award in Pharmacology and Toxicology, which recognizes both his academic excellence and his involvement in the arts. The award is named in honour of Jurima-Romet, who earned her PhD from the department while doing research into pharmacogenetics.

Before her death last year from cancer, Jurima-Romet had a diverse range of interests encompassing both science and art. As a scientist focused on drug metabolism, she wrote more than 60 peer-reviewed publications, and co-edited books on biomarkers in drug development as well as drug-to-drug interactions. During her career, she worked as a scientist for Health Canada followed by a successful career in the pharmaceutical and biotechnology industry and served as an adjunct professor at both the University of Montreal and the University of Ottawa.

Jurima-Romet was also an accomplished artist who worked with watercolour and oil paints as well as pastels. She received invitations to display her work at group and solo shows, and her paintings can be found in private collections in Canada, the United States and Europe. She was also a master instructor of Japanese Ikebana flower arranging and had a love for music with included experience playing piano and violin.

Like Jurima-Romet, Zhou’s passions include science and art.

“Dance not only gave me a brand new experience, it also gave me a new way to reduce stress,” he says.“I feel happy after I dance and that happiness helps me overcome despair or frustration after a difficult day in the lab.”

Zhou’s PhD studies explore nitroglycerin, which has been most commonly used to treat angina for more than 100 years. Despite the drug’s well-established utility for treating chest pain, scientists still don’t understand why it is effective, and why people become less responsive to it during long-term therapy. Zhou focuses on a special protein called aldehyde dehydrogenase (ALDH-2), which some scientists believe could be responsible for making nitroglycerin work. This protein might become inactivated during chronic treatment.

Many people, and especially people with Asian ancestry, carry ALDH-2 in a mutated form. Current literature suggests this mutation may cause the protein to function less efficiently. Zhou wants to know if this protein is what makes the drug work, and if so, whether the dose and delivery method need to be tailored for people with the enzyme mutation. He also wants to know how this protein becomes inactivated in patients during long-term treatment.

“My mother had angina when I was a child. I can remember her asking me to grab her medication whenever she had acute chest pain. That’s what inspired me to become involved in drug research.”

As Zhou completed his BSc at the University of British Colombia, he began to dabble in salsa dance. While he pursued his MSc, Zhou also trained at a professional Latin dance school, helping him maintain a balanced lifestyle and grow a broad social network. As he began his PhD studies at 91�Թ�, he joined the 91�Թ� Dance Club and took dance classes at Hart House. He went on to launch a new club called Urban Dance Revolution, which offers affordable lessons to 91�Թ� students.

“Graduate and PhD students may not have opportunities to pursue outside interests because often they just don’t have that extra money to do it,” says Tiit Romet, Jurima-Romet’s husband of more than 25 years, who established the award. “There’s more to a person than academics. If a student can realize some of their other potential and feed their passion for something else like music or art while they are furthering their education, their university experience will be all the better.”

The award will help Zhou further his own dance training while expanding the dance club and its work.

“I want students to have a chance to learn from – and be inspired by – their peers instead of professional instructors,” Zhou says. “These students might say, ‘I see my dance ‘instructor’ is taking the same academic classes I am, so maybe one day I can become like them.”

(Learn more about Urban Dance Revolution)

picpath

sites/default/files/2015-12-03-dance-class.jpg

Building a better heart: celebrating the first year of the Ted Rogers Centre for Heart Research

sgupta — Fri, 20 Nov 2015 10:35:39 +0000

Building a better heart: celebrating the first year of the Ted Rogers Centre for Heart Research sgupta Fri, 11/20/2015 - 05:35

Cutline

Professor Craig Simmons and Professor Peter Zandstra (standing) are two of the leading researchers driving scientific discovery and the development of new therapies at the Ted Rogers Centre for Heart Research

Heidi Singer

Author legacy

Heidi Singer

What if we could identify the gene responsible for a baby’s heart defect, grow a piece of her heart on a chip, then test drugs to find the one able to shut down the defective gene?

A decade ago, that scenario seemed as far-fetched as a Mars landing. Today, 91�Թ� researchers predict these stunning achievements are just a few years away, thanks to the Ted Rogers Centre for Heart Research – a powerful collaboration between scientists from 91�Թ�’s medical and engineering faculties and physicians from SickKids and the University Health Network.

As the Centre celebrates its first anniversary and 91�Թ� researchers prepare to move into the MaRS West Tower, which will be the Centre’s new home, writer Heidi Singer of the Faculty of Medicine spoke with Professor Craig Simmons, who leads 91�Թ�’s collaboration as scientific director for the Translational Biology and Engineering Program.

What is 91�Թ�’s role in the Centre?
Our mission is to help discover the causes of heart failure and engineer therapies. We’re making fundamental discoveries about the mechanisms of cardiac diseases, discovering new biomarkers and building heart tissues with molecules, cells and biomaterials. The overall mission is to reduce hospital admissions due to heart failure by 50 per cent within 10 years. That’s very ambitious, but it can be done. The key is to bring everyone together: medical researchers, doctors, engineers and many other specialties.

Our new space will help make it happen. It’s state-of-the-art, highly integrated and interdisciplinary. We have a whole floor and eventually we’ll have 130 people there. Engineers will be sitting beside biologists who are sitting beside clinicians. This will spark collaborations that would never have happened otherwise.

Can you describe some of the most exciting work at the Centre?
Let’s say a baby is born with heart problems and a doctor at SickKids finds a gene associated with heart failure. Using stem cells from the baby, we can create a model of that child’s heart on a platform that looks like a chip. Then we can do personalized drug testing on the chip before the child ever swallows a pill. The technology exists now. I’m collaborating with a cardiologist who gets the stem cells from the patient and creates heart muscle cells. We put it on the chip. Then we would test drugs on it.

We’re also growing living replacement heart valve tissue in the lab. This could replace our current solution, which is mechanical heart valves that require people to be on blood thinners the rest of their lives. This is important for children because often we replace a valve in babies with fabric. That works for a bit and then they need multiple operations to replace it. What if we can get the baby’s cells from the umbilical cord and grow a heart valve that’s living tissue that will grow with the baby and adapt as the baby grows? We’re doing the same with blood vessels and heart muscle. Instead of using synthetics and other artificial replacements, we could use living replacements that would require one surgery to fully restore function.

We’re already in the early stages, and while we’re several years away from success, all the technology is in place. The demand is there. We know from the surgeons that the current state of the art isn’t great. The challenge now is to create tissues that are comparable to what’s in the body already.

You’re a mechanobiologist. Explain.
This is a field that’s been emerging over the past decade. We’re interested in how mechanical forces in the body affect cell function. We study the heart valve a lot. It opens and closes with every beat of the heart. The valve stretches and bends when blood rushes by. If you have high blood pressure or a malformed valve it causes even more mechanical stress, contributing to valve disease. Most people think of something in the blood, like cholesterol, causing heart disease. But cells react to mechanical forces. One day we’ll make a drug that desensitizes heart cells to mechanical forces.

Dream a bit. What will cardiac care look like in 50 years?
We’ll have injectable biomaterials and molecules to help the heart heal itself. Some animals, like zebrafish, can do it. Whatever gene allows them to do it, maybe we can turn that gene on in humans.

In addition, our ability to grow your exact heart cells in a lab will allow us to conduct drug trials in a Petri dish instead of on an animal. Thiswill give us lightning-fast results. It’s taking some of the guess work out by eliminating something that’s going to fail. Right now drugs are screened in animal models that don’t match up to human biology perfectly. That’s one reason why most promising research falls apart when we get to human trials, which is why it costs so much and takes so long to develop a drug. We could eliminate those false positives sooner and develop personalized drugs for your heart.

Is there anything like the Ted Rogers Centre for Heart Research anywhere in the world?
It’s unique in terms of the number and diversity of people we have. There’s the potential to be in the top five in the world for cardiovascular research and maybe the number one in the world for heart failure. That will come to fruition if we can bring everyone together and synergize. That’s where we’ll really see the potential fulfilled.

picpath

sites/default/files/2014-11-19-researchers2.jpg

Defibrillators: making sure they're accessible when and where heart attacks are most likely to happen

sgupta — Tue, 10 Nov 2015 15:28:38 +0000

Defibrillators: making sure they're accessible when and where heart attacks are most likely to happen sgupta Tue, 11/10/2015 - 10:28

Cutline

(photo by Liz Do)

Liz Do

Author legacy

Liz Do

Topic

Subheadline

Research finds life-saving devices are often located in buildings and facilities with limited opening hours

Walking through an office building on St. George Street, Engineering's Christopher Sun quickly spots a portable automated external defibrillator (AED) conveniently tucked near the side of the entrance.

From 8 a.m. to 9 p.m., its accessibility could be vital in saving a life. But after the building closes at 9 p.m., it is almost as if the AED isn’t there.

That problem is what the PhD student's research is examining, with Associate Professor Timothy Chan of Mechanical & Industrial Engineering and in collaboration with St. Michael’s Hospital and its Rescu program, led by Dr. Laurie Morrison.

Sun recently presented their findings at the American Heart Association (AHA) conference in Orlando. Chan had previously presented at the AHA conference in 2010, sharing his findings on the placement of registered AEDs in Toronto and Peel Region. What he discovered back then was that spatial distribution of AEDs was not optimal.

“Our original finding was that less than one in four cardiac arrests occurred near an AED,” Chan said.

Sun’s research takes that research a step further.

“Previous work has focused almost entirely on spatial factors,” said Sun. “Time factors, such as when cardiac arrests occur and the time of day, have been largely overlooked.

“We found that if we do take into account time, there is a significant decrease in perceived coverage of cardiac arrests.”

Based on the hours of the buildings where AEDs are placed, the research revealed that AED coverage was diminished more than eight per cent during the day, 28 per cent in the evening and 48 per cent at night.

His research also found that only some buildings in Toronto are accessible 24 hours a day and seven days a week. Many AEDs are located within office buildings, schools and recreation facilities, which tend to be open for a limited set of hours during the daytime.

“There’s definitely a gap there,” said Sun. That gap can be the difference between life and death.

Over a period of roughly eight years, 2,440 out-of-hospital cardiac arrests occurred in Toronto. Of those that occurred near an AED, approximately one in five occurred when an AED was inaccessible.

“Emergency medical services and investigators are united and willing to reposition AEDs to locations that are accessible,” said Dr. Morrison, an emergency medicine specialist at St. Michael’s and collaborator in the research.

According to Sun and Chan, the true coverage of cardiac arrests is overestimated when temporal factors are not considered. To address this issue, they have developed an optimization approach that can regain that lost coverage by optimizing AED deployment in more time-available buildings. This research was also recently presented at the AHA conference.

“We’ve developed the first mathematical optimization approach for AED deployment that considers both spatial and temporal availability to improve cardiac arrest coverage,” said Chan, who is the Canada Research Chair in Novel Optimization and Analytics in Health, and leads the Centre for Healthcare Engineering (CHE) as well as the Applied Optimization Lab (AOL) at 91�Թ� Engineering.

“We found that our model provided the largest improvement in coverage during the night, which was precisely when the largest loss in coverage due to limited temporal accessibility was experienced, as well as when survival was lowest.”

Chan said he hopes this research demonstrates how critical temporal accessibility is to both the measurement of true cardiac arrest coverage as well as the decision on where to locate AEDs.

“Our optimization model can be beneficial towards developing policies and guidelines for AED placements across the world, and ultimately to help save more lives,” said Chan.

Alongside Sun’s findings, Chan’s AOL researchers will continue to focus their attention on the city’s distribution of AEDs. The lab is analyzing the optimization of defibrillators in high-rise buildings, as well as in Toronto’s heavily frequented PATH underground walkway.

picpath

sites/default/files/2015-11-10-debrillator-sun.jpg

New “Tissue Velcro” could help repair damaged hearts

sgupta — Mon, 31 Aug 2015 15:44:21 +0000

New “Tissue Velcro” could help repair damaged hearts sgupta Mon, 08/31/2015 - 11:44

Cutline

New technique could go beyond heart cells. “Conceptually, there is really no limitation,” says Professor Milica Radisic (Photo by Caz Zyvatkauskas)

Tyler Irving

Author legacy

Tyler Irving

Topic

Subheadline

91�Թ� engineers made assembling heart tissue faster and easier

Engineers at the 91�Թ� just made assembling functional heart tissue as easy as fastening your shoes.

The team has created a biocompatible scaffold that allows sheets of beating heart cells to snap together just like Velcro™.

“One of the main advantages is the ease of use,” says Professor Milica Radisic, who led the project. “We can build larger tissue structures immediately before they are needed, and disassemble them just as easily. I don’t know of any other technique that gives this ability.”

Growing heart muscle cells in the lab is nothing new. The problem is that too often, these cells don’t resemble those found in the body. Real heart cells grow in an environment replete with protein scaffolds and support cells that help shape them into long, lean beating machines.

In contrast, lab-grown cells often lack these supports, and tend to be amorphous and weak. Radisic and her team focus on engineering artificial environments that more closely imitate what cells see in the body, resulting in tougher, more robust cells.

Two years ago, Radisic and her team invented the Biowire, in which heart cells grew around a silk suture, imitating the way real muscle fibres grow in the heart.

“If you think of single fibre as a 1D structure, then the next step is to create a 2D structure and then assemble those into a 3D structure,” says Boyang Zhang a PhD candidate in Radisic’s lab.

Zhang and Miles Montgomery, another PhD student in the lab, were co-lead authors on the current work, published Aug. 28 in Science Advances. The ‘tissue Velcro™’ discovery has already made headlines around the world, with features in Popular Science, Gizmodo and more.

Zhang and his colleagues used a special polymer called POMaC to create a 2D mesh for the cells to grow around. It somewhat resembles a honeycomb in shape, except that the holes are not symmetrical, but rather wider in one direction than in another.

Critically, this provides a template that causes the cells to line up together. When stimulated with an electrical current, the heart muscle cells contract together, causing the flexible polymer to bend.

Next the team bonded T-shaped posts on top of the honeycomb. When a second sheet is placed above, these posts act like tiny hooks, poking through the holes of honeycomb and clicking into place. The concept is the same as the plastic hooks and loops of Velcro™, which itself is based on the burrs that plants use to hitch their seeds to passing animals.

The diagram below shows how T-shaped posts on one layer of a tissue scaffold pass through the holes in a second layer — similar to the hooks and loops used to fasten Velcro™ (Image by Raymond Cheah).

Amazingly, the assembled sheets start to function almost immediately.

“As soon as you click them together, they start beating, and when we apply electrical field stimulation, we see that they beat in synchrony,” says Radisic.

The team has created layered tissues up to three sheets thick in a variety of configurations, including tiny checkerboards.

The ultimate goal of the project is to create artificial tissue that could be used to repair damaged hearts. The modular nature of the technology should make it easier to customize the graft to each patient.

“If you had these little building blocks, you could build the tissue right at the surgery time to be whatever size that you require,” says Radisic. The polymer scaffold itself is biodegradable; within a few months it will gradually break down and be absorbed by the body.

Best of all, the technique is not limited to heart cells.

“We use three different cell types in this paper; cardiomyocytes, fibroblasts and endothelial cells, but conceptually there is really no limitation,” says Radisic.

That means that other researchers could use the scaffold to build layered structures that imitate a variety of tissues, livers to lungs. These artificial tissues could be used to test out new drugs in a realistic environment.

Moreover, the ability to assemble and disassemble them at will could enable scientists to get much more detailed information on cell response than is currently possible.

“You could take the middle layer out, to see what the cells look like,” says Radisic. “Then you could apply a molecule that will cause differentiation or proliferation or whatever you want, to just that layer. Then you could put it back into the tissue, to see how it interacts with the remaining layers.”

The next step is to test how well the system functions in vivo. Radisic and her team are collaborating with medical researchers in order to design implantation experiments that will take the project one step closer to the clinic.

picpath

sites/default/files/2015-08-28-biomedical-engineering-professor-Milica-Radisic.jpg