Event Name: Graduate Seminar Series: Clinical Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for clinical stream presenters.

Presentation Title: Vision-based Assessment of Parkinsonism in Gait

Abstract: Parkinsonism can result in significant deterioration in gait when compared to age-matched controls. Furthermore, parkinsonism severity in gait can vary on a day-to-day basis so monitoring patients for rapid changes in gait quality is important to allow clinicians to identify and address reversable causes. Currently, formal gait assessments are performed by trained experts during clinical visits which are too infrequent to capture short-term changes in gait. When paired with state-of-the-art pose tracking algorithms, vision-based systems provide an opportunity to unobtrusively monitor gait in non-clinical settings. This project seeks to assess how gait features and joint trajectories extracted from standard colour video can be used to score severity of parkinsonism in gait on clinical rating scales. Correlations between gait features obtained from vision-based systems and those obtained using an instrumented mat will be calculated. Additionally, correlations between vision-based gait features and clinical scores of parkinsonism in gait will be analyzed. Finally, machine learning models will be developed to assess how well joint trajectories extracted from video can be used to predict parkinsonism severity in previously unseen patients. It is hypothesized that this project is to provide insight into the algorithms and processing considerations for assessing parkinsonian gait using color video.

Supervisor Name: Dr. Babak Taati

Year of Study: 2

Program of Study: MASc

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Cell and Tissue Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for cell and tissue stream presenters.

Presentation Title: Molecular control of collagen biomineralization: principles and application to multiphasic scaffold design

Abstract:
Collagen mineralization is an important process for the formation of bone and other mineralized connective tissues. While the type and extent of crosslinking of collagen differ from tissue to tissue little is known about how crosslinking affects collagen mineralization. In recent years, researchers have developed in vitro models aiming to understand how collagen mineralization is regulated. It is essential for the models to mimic the characteristics of natively mineralized collagen fibrils. Previous studies have reproduced intrafibrillar and aligned mineral in reconstituted collagen, but very few studies have successfully reproduced the preferential gap zone mineralization.
This study aims to analyze how crosslinking affects collagen mineralization, including the type and extent of crosslinking. Collagen fibrils were prepared by raising the pH of acid soluble collagen. Glutaraldehyde or 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) was used to crosslink collagen fibrils. The crosslinked collagen fibrils were mineralized in a metastable mineralization solution stablized by polyaspartic acid, and then analyzed by transmission electron microscopic.
The distribution and orientation of mineral formed in collagen fibrils were influenced by the crosslinking. The fixation of collagen resulted in mineralized collagen with banded pattern, corresponding to preferential gap zone mineralization, which was not observed in unfixed collagen. This is an important step of successfully producing intrafibrillar, well-aligned and banded mineralized collagen fibrils. The results help to understand the regulation of collagen biomineralization.

Supervisor Name: Eli Sone

Year of Study: 4

Program of Study: PhD

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Clinical Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for clinical stream presenters.

Presentation Title: Inferring Parameters of Short-term synaptic Plasticity from in-vivo Recordings of Human Brain

Abstract:
Background:
Short-term synaptic plasticity (STP) is the dynamic of change in the synaptic weight according to the presynaptic spiking activity. Recent studies showed that STP is involved in several brain processes such as controlling the voluntary movements. Therefore, study STP and inferring its parameters facilitates the understanding of brain processes and disorders (e.g. Parkinson’s Disease). In this project, we will develop a new method for inferring STP parameters from in-vivo data compatible with the human application. Several works have been done on inferring STP parameters using in-vitro intracellular recordings of rodents [1-4], however, in this project I propose a method to infer these parameters from in-vivo recordings of human data during Deep Brain Stimulation surgery. The information that will be provided by this method can be useful in the study of brain processes.
Objectives:
(1) To implement synaptic plasticity and infer its parameters from human data in order to have the closest simulation of human neural activity.
(2) To estimate the probability distribution of synaptic plasticity parameters of human neurons.
(3) To analyze the dynamics of the synaptic plasticity and its resistance to perturbation.

Data:
To acquire spiking activity, two closely spaced microelectrodes were placed in the thalamic ventral intermediate nucleus (Vim) during awake DBS surgeries. One electrode was used to record single-unit spiking activity, while the other was used to deliver stimulation pulses at various frequencies (5Hz, 20Hz, 30Hz, 50Hz, 100Hz, 200Hz). The included data were collected from 15 patients [5]. The narrow stimulus pulses were removed, after which data were high pass filtered to better isolate single-unit activity. Using stimulus artifacts as triggers, we extracted the instantaneous firing rate of neurons in response to each DBS pulse of the 5Hz stimulation trains and averaged over all inter-pulse intervals. Due to the low stimulation rate (i.e. 5Hz), no STP is induced in this data. The resultant waveform is equivalent to the linear filter of the Linear-Nonlinear (LN) model.
Method:
In order to mimic STP behavior, we are using the Tsodyks-Markram phenomenological model, which generates the postsynaptic current according to the spiking history of the presynaptic neuron [6]. To reconstruct the firing rate induced by DBS, we give the impulse train of DBS as the input of the Tsodyks-Markram model. The model generates a postsynaptic current in response to DBS pulses. we use this response to make modulated pulse trains that represent the effect of STP by changing the amplitude of each pulse. The modulated pulse will pass through a LN neuron model neuron in order to estimate the DBS-induced firing rate.
To achieve the true parameters of the Tsodyks-Markram model we should minimize the error between the experimental and estimated firing rate. True parameters should be valid for all frequencies; therefore, we define the error function as the average error of 30Hz, 50Hz, 100Hz, and 200Hz frequencies. To minimize the error, we employ Bayesian Adaptive Direct Search [7], which is a fast non-derivative optimization algorithm. In addition, we are developing another fitting method based on Deep Neural Networks that infer the distribution of parameters and give us more information about the dynamic of STP.

Significance:
The result of this work can be used to have an accurate simulation of large networks of Basal Ganglia Network to study neurological disorders such as Parkinson’s Disease. Having the true parameters of STP can help us to understand the difference between human and rodent neurons and have better intuition in using animal subjects in electrophysiology studies.
In addition, estimating the probability distribution of the STP parameters can be used as an analyzing tool for investigating the stability of the dynamical system of the brain. we predict that there would be a difference between the morphology of the healthy and PD synapses, and it can be used as a diagnostic tool or a guide to improving DBS treatment.

Supervisor Name: Milos Popovic, Milad Lankarany

Year of Study: 2

Program of Study: MASc

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Molecular Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for molecular stream presenters.

Presentation Title: Liposome Imaging in Optically Cleared Tissues

Abstract: Three-dimensional (3D) optical microscopy can be used to understand and improve the delivery of nanomedicine. However, this approach cannot be performed for analyzing liposomes in tissues because the processing step to make tissues transparent for imaging typically removes the lipids. Here, we developed a tag, termed REMNANT, that enables 3D imaging of organic materials in biological tissues. We demonstrated the utility of this tag for the 3D mapping of liposomes in intact tissues. We also showed that the tag is able to monitor the release of entrapped therapeutic agents. We found that liposomes release their cargo >100-fold faster in tissues in vivo than in conventional in vitro assays. This allowed us to design a liposomal formulation with enhanced ability to kill tumor associated macrophages. Our development opens up new opportunities for studying the chemical properties and pharmacodynamics of administered organic materials in an intact biological environment. This approach provides insight into the in vivo behavior of degradable materials, where the newly discovered information can guide the engineering of the next generation of imaging and therapeutic agents.

Supervisor Name: Warren Chan

Year of Study: 4

Program of Study: PhD

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Clinical Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for clinical stream presenters.

Presentation Title: Designing effective visual scene displays (VSDs) for children with complex communication needs

Abstract: Augmentative and alternative communication (AAC) is one of the intervention options beneficial to individuals with significant speech and language impairments, including beginning communicators. Visual scene displays (VSDs) with just-in-time feature have also shown promising results to facilitate beginning communicators’ ability to learn new vocabularies based on familiar scenes. Although “Just-in-time” refers to access to vocabularies as they are needed at the moment in the literature, it has still needed a communication partner to program vocabularies for a child. In order to make just-in-time an actual feature, machine learning algorithms can be leveraged to automate this process. This research aims to empower children with CCN to communicate and interact with their environment in a meaningful way, and to accelerate their progress in language learning. Harnessing machine learning and artificial intelligence has the potential to advance language learning toolkits and the quality of life for children with CCN.

Supervisor Name: Tom Chau

Year of Study: 2

Program of Study: PhD

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Cell and Tissue Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for cell and tissue stream presenters.

Presentation Title: An in vitro model for skeletal muscle regeneration and its potential as a screening platform

Abstract: The field of tissue engineering combines different disciplinary approaches to create synthetic or lab-grown biological tissues, and is widely applied in medicine, pharmacy, diagnostics, and basic research. By creating models of various tissues, scientists can study biological phenomena in a more isolated and higher-content setting (i.e. more samples). However, creating these models becomes technically challenging since cells demand a highly organized environment that mimics human tissue. Conversely, the model must be simple enough to allow for easy use, compatibility with common experimental techniques, and widespread adoption among peers. This is especially highlighted in efforts to create models of human skeletal muscle to study healing. Compared to other tissue types, human skeletal muscle has a remarkable regenerative ability, and is therefore one of its most studied properties. However, understanding this complicated process has been limited to animal studies that are tedious and timely, since most muscle models have little to no regenerative capabilities. To address this gap, our lab, in collaboration with the McGuigan Lab (UofT, Chemical Engineering), established a 24-well plate-sized model to study human muscle regeneration, termed the Muscle Endogenous Repair (MendR) model. With MEndR’s feasibility confirmed, the goal of this project is to miniaturize and automate the model to create a high-content testing platform that will be used to search for drugs that can improve human skeletal muscle regeneration

Supervisor Name: Dr. Penney Gilbert

Year of Study: 2

Program of Study: PhD

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Cell and Tissue Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for cell and tissue stream presenters.

Presentation Title: Reversing the Hallmarks of Aging via Interrupted Reprogramming

Abstract: To develop efficient and viable personalized cell-based therapies for lung diseases, the functional state of the cell source is a critical component of the treatment. The objective of my work is to use interrupted reprogramming to restore age-related deterioration in stem cell self-renewal capacity, enzyme activity and repair mechanisms for nuclear and mitochondrial DNA, to a younger state. This has a significant clinical impact as we can now imagine a cell-based therapeutic approach in which aged cells from older patients can be isolated and reprogrammed to create expanded numbers of progenitor-like cells, which are now phenotypically and functionally similar to much younger cells. IPF is particularly interesting as a growing body of evidence reveals that the extent of epithelial cell injury, repair processes, and ageing are key determinants in the pathogenesis of the disease.

Supervisor Name: Dr. Thomas Waddell

Year of Study: 2

Program of Study: PhD

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Clinical Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for clinical stream presenters.

Presentation Title: Design, Development, and Evaluation of a Voice Based Chronic Disease Management Program

Abstract: Digital health refers to the use of communication technologies, services, and processes to deliver health care services. Most of these services are accessed through personal computers and smartphones, where their ubiquitous nature makes it easy for the patient to manage their health. Similarly, “smart” speaker devices are also becoming ubiquitous due to many compelling features such as ease of use, convenience, and affordability, and continue to gain popularity in consumer households. Voice apps (which are accessed through smart speaker devices) may be a suitable platform to deploy home patient monitoring programs on, since the user is expected to vigilantly track and report relevant health data. Voice apps may offer an easier, alternative method for data collection and interaction. This thesis will use Medly, a smartphone-based heart failure management program, as a case-study to understand how people with chronic diseases that need vigilant tracking, might interact with voice apps.

Supervisor Name: Dr. Joseph Cafazzo

Year of Study: 2

Program of Study: MASc

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Clinical Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for clinical stream presenters.

Presentation Title: Creation of a Diagnostic Training Tool for Developmental Dysplasia of the Hip (DDH)

Abstract: Developmental Dysplasia of the Hip (DDH) is the most common orthopaedic disease in children, where the acetabulum develops too shallow to properly constrain the femoral head, leaving the hip unstable and prone to dislocation. There is currently no standardized training nor simulation tools provided to health care professionals to learn to diagnose DDH and as a result, thousands of avoidable surgeries are performed each year. A device that accurately simulates the condition would markedly enhance our ability to teach health care providers how to perform the clinical examination and what to feel for during each maneuver to facilitate the diagnosis being made during the first post-natal check-up. This project will develop a high-fidelity simulation model and validate its ability to produce accurate tactile feedback consistent with that of a patient’s natural hip.

Supervisor Name: Jan Andrysek, Simon Kelley

Year of Study: 2

Program of Study: MHSc

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com

Event Name: Graduate Seminar Series: Cell and Tissue Stream

Graduate Seminar Series for the Institute of Biomedical Engineering (BME). This day is for cell and tissue stream presenters.

Presentation Title: Lung Airway-on-a-Chip with Airflow System for Studying Epithelium and Smooth Muscle Interactions

Abstract:
Chronic respiratory diseases are responsible for more than 4 million deaths per year. One of the main symptoms is airway obstruction which is a multicellular disorder caused by the abnormal airway smooth muscle (ASM) contractions especially with the presence of inhaled particulate matters (PM). For the last decade, the organ-on-a-chip technologies have been suggesting a breakthrough by enabling the human-originated cell cultures on a micro-engineered 3D environment. Studies also attempted to represent the lung airways using this technology, but the challenge remains due to the difficulty of characterizing the airway epitheliums. Moreover, the current PM delivery systems are limited as they lack the features of flow-driven applications like the native airways.
To address these issues, this study developed a micro-milled thermoplastic lung airway-on-a-chip for coculturing the airway epithelial cells and ASM cells on a suspended hydrogel. In addition, an airflow system that can manipulate the flow rate, humidity and temperature of the air was developed to provide various airflows that can correlate to the aerodynamics in different regions of the lung airway. Early results showed that after a 24-hour application of airflow on the airway epithelial cells showed significant elongations of some motile cilia than the cells cultured in submerged or air-liquid interface (ALI) conditions.
This study is expected to enable further investigation of the mechanobiological effects of airflow on the lung airway epithelium. Furthermore, the flow-driven application of PM deposition using the airflow system is expected to induce more accurate pathological responses from the interactions between the ASM and the airway epithelium.

Supervisor Name: Edmond W. K. Young

Year of Study: 4

Program of Study: PhD

Zoom link: https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09  (https://us02web.zoom.us/j/88202111033?pwd=cEoxaU0zN1ljYkNiUlpXblNjalBKdz09)

Meeting ID: 882 0211 1033 

Password: 634938

Powered by Calendly.com