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Examining the impact of physiologically patterned EMF and LED on the growth of malignant cells: an analysis of the Novel Ca2+ EMF
No full textIt has been proposed that all living biological systems are capable of emitting or
detecting electromagnetic energies as a way of communicating within and between
individual units. Should this statement be valid, it opens the door to the possibility of
manipulation through artificial application of the appropriately patterned
electromagnetic energy. Common forms of electromagnetic energies that are relevant to
biological systems include electromagnetic fields and light. Here we explore the
possibility for physiologically patterned, frequency modulated electromagnetic fields
(EMF) and light-emitting diodes (LED) to influence the growth and viability of malignant
(B16-BL6) and non-malignant (HEK 293-T) cell lines. When applied for a single 40-
minute exposure, the novel, physiologically patterned Ca2+ EMF reduced the growth of
malignant cells 50.3%. Importantly, this same procedure had no effect on non-malignant
cells. When applied as an LED, the effects of the Ca2+ pattern were entirely dependent
on the wavelength of light. While red (645 nm) LED demonstrated a significant reduction
in B16 viable cell counts consistent with the anti-cancer properties of the EMF, blue (470
nm) LED promoted a significant increase in viable cell counts. Finally, we sought to
determine the most optimal application parameters of the Ca2+ EMF by adjusting its
temporal characteristics. Reducing the point durations from 10 ms to 3 ms further
decreased the viability of B16 cells therefore suggesting 3 ms as the optimal time
increment for anti-cancer effects. Overall, these results show the ability for specifically
patterned EMF and LED to influence the growth of malignant tissues. As such, our
findings pose the potential for the Ca2+ EMF to act as a specific, non-invasive, cost-
effective therapeutic to be used in the treatment of cancers.Master of Science (M. Sc.) in Biolog
A hybrid Convolutional Neural Network (CNN) and Support Vector Machine (SVM) for detecting Keratoconus in patients using genetic algorithm
No full textNowadays, there are still significant challenges encountered in the accurate diagnosis of various eye diseases, such as Keratoconus (KCN) and cataracts. Early detection of Keratoconus is crucial in preventing its progression and ensuring the best treatment outcomes. Artificial intelligence (AI) is being widely applied in ophthalmology through the training of deep learning networks for the early detection of eye diseases. This research presents a novel, integrated machine learning approach for diagnosing Keratoconus disease by combining feature extraction through Convolutional Neural Networks (CNN) with a Support Vector Machine (SVM) and Artificial Neural Network (ANN) for classification. Employing a multi-objective genetic algorithm, the method optimizes feature selection, aiming to minimize both diagnostic error and the number of features. The study utilizes a dataset of 5,152 ophthalmic images (1288 samples) categorized into Normal (476), Suspect (453), and Keratoconus (359) cases, sourced from an eye clinic in Egypt. Combining a Convolutional Neural Network (CNN) for feature selection with a Genetic Algorithm (GA) significantly improved diagnostic accuracy. Consequently, by focusing on the most relevant features of Keratoconus (KC), the model achieved an impressive 98.63% accuracy for ANN classification with a genetic algorithm, and 98.13% for SVM classification with a genetic algorithm. The accuracy of the algorithm exceeded that of when SVM and ANN were used without the genetic algorithm alone, which were 97.53% and 96.9% respectively, underscoring the benefit of combining Artificial Neural Networks (ANNs) with Genetic Algorithms (GAs) in KC diagnosis. Implementing this model can assist physicians in more accurate Keratoconus detection, providing better predictions regarding patients' eye conditions, and offering timely treatment recommendations
Influence of sex hormones on catecholamine biosynthesis: the roles of progesterone and estrogen
Get PDFCatecholamines are hormones/neurotransmitters that play a key role in various physiological systems, including cardiovascular regulation and the stress response. Elevated levels of catecholamines have been linked to hypertension, with men typically having a higher prevalence of hypertension under the age of 50 compared to women. However, this trend reverses in post-menopausal women. Sex differences in hypertension and stress response are thought to be influenced, in part, by the sex hormones estrogen (E2) and progesterone (P). Despite this, the mechanisms by which P and E2 regulate catecholamine biosynthesis are poorly understood. While some research has focused on tyrosine hydroxylase (TH), limited studies are available on dopamine beta-hydroxylase (DBH) and phenylethanolamine-N-methyltransferase (PNMT). In women, E2 is thought to downregulate catecholamine production by altering biosynthetic enzyme activity and is therefore considered cardioprotective. Similarly, P has been shown to modulate catecholamine biosynthesis, though the exact mechanism remains unclear. This study examined the regulation of TH, DBH, and PNMT in PC12 cells treated with varying concentrations of P and E2. In addition, the potential role of P and E2 in modulating the neural (forskolin) and hormonal (dexamethasone) regulation of catecholamine bionsynthetic enzymes was examined. The overexpression of estrogen receptor (ER) subtypes alpha and beta via CRISPR activation (CRISPRa) was also investigated to further elucidate ER-mediated effects. Treatment with P and E2 hormones alone had no significant effect on TH, DBH, or PNMT mRNA expression. Dexamethasone treatment significantly increased mRNA expression of TH, DBH, and PNMT, and progesterone and estrogen potentiated the dexamethasone-induced increase in TH mRNA expression. Progesterone also attenuated DBH mRNA expression. These findings suggest that P and E2 modulate catecholamine biosynthesis and may contribute to the observed sex differences in hypertension prevalence
Are less credible alibis also perceived as more similar to each other?
No full textPsychological factors influencing the perceived value of alibis from the perspectives of police officers and jurors warrant careful examination due to their potential to lead to false accusations or convictions. While alibis should theoretically hold equal value regardless of presentation context, research by Sommers and Douglass (2007) suggests otherwise, revealing that contextual factors impact alibi credibility judgments. In their study, the same alibi was perceived as less credible when presented in a “criminal trial” context in comparison to a “police investigation” context. In the sensory domain, when the same odorants are labeled as “body odours” rather than “cheese odours,” not only are they perceived as less pleasant, but this hedonic deflation effect is accompanied by a condensation effect; where the preference for one odorant over another is reduced (Zellner et al., 2014). Is the label-induced alibi credibility deflation effect, observed in a “criminal trial” context by Sommers and Douglass (2007), likewise accompanied by a condensation effect, making less credible alibis also more similar to each other? In the present study, when the alibis were accompanied by a strong motive to commit the crime (Experiment 2), a condensation effect emerged in the “criminal trial” context, in line with our hypothesis. In contrast, when the alibis were accompanied by a weak motive, alibis were perceived as less credible in the “police investigation” context. Furthermore, when no motive was included at all (Experiment 1), the label-induced alibi credibility deflation effect reported by Sommers and Douglass (2007) vanished. These findings underscore the need to consider the motivation to commit a crime when examining contextual effects on alibi credibility judgments.Social Sciences and Humanities Research Counci
Effects of hydrogen sulfide on lipid metabolism in adipocytes and adipose tissues
No full textHydrogen sulfide (H2S) is a gasotransmitter involved in various physiological processes. Studies indicate that H2S enhances adipogenesis and lipid accumulation in 3T3-L1 adipocytes, though the mechanism is unclear. Therapeutic applications with H2S are limited by the lack of targeted delivery routes and its rapid dispersal in vivo. While H2S shows lipogenic effects on adipocytes in vitro, its impact on adipose tissue in vivo is not well understood.
This study is novel in two ways: first, we elucidate a cell signalling pathway in isolated mouse preadipocytes by which H2S increases adipogenesis, adipocyte hypertrophy, and adipocyte hyperplasia in vitro. Second, we utilize a novel H2S-slow-releasing hydrogel (SATO-IAVE2) to deliver H2S locally to subcutaneous adipose tissue, examining lipid accumulation in mice.
In in vitro study, lowering endogenous H2S levels via cystathionine γ-lyase knockout (CSE KO) or a CSE inhibitor reduced lipid accumulation and adipogenesis in adipocytes. However, simultaneous treatment with exogenous H2S increased adipogenesis and lipid accumulation. Exogenous H2S enhanced lipid accumulation in primary mouse adipocytes, upregulating genes related to hyperplasia (C/EBPβ, Cdc25, Mcm3, Cdc45) and cyclin-dependent kinase 2, and activated the insulin receptor β, MAPK, and Akt pathways. Under nutrition overload conditions, H2S increased glucose consumption and exacerbated adipocyte hypertrophy.
In in vivo study, we injected two doses of an H2S-releasing hydrogel SATO-IAVE2 (39 and 78 μmol/kg) and a control gel C-IAVE4, which releases oxygen instead of H2S, into the subcutaneous adipose tissue of both CSE-KO and wild-type (WT) mice. These injections were given every six days for a month. After 30 days, compared to the control, H2S- releasing hydrogel increased lipid accumulation and metabolism in both WT and CSE KO mice. In CSE KO mice, only higher dose of the H2S-releasing hydrogel increased lipid accumulation and lipid droplet size, associated with higher SREBP, PPARγ, adiponectin, and perilipin levels. In WT mice, both doses of SATO-IAVE2 increased lipid accumulation, but higher dose causing significant lipid buildup and adipocyte hypertrophy, with increased PPARγ, SREBP, and perilipin. Hormone sensitive lipase (HSL) phosphorylation increased while adiponectin expression decreased with higher dose of SATO-IAVE2 in WT mouse adipose tissue.
Both in vitro and in vivo studies reach the same conclusion that H2S promotes lipid accumulation in mouse adipocytes. Lipolysis remained unaffected in vitro, while in vivo, higher H2S doses increased HSL phosphorylation in WT mice. The effect of H2S on lipolysis in vivo needs to be studied further. Our study confirms the feasibility of selectively delivering H2S via injectable SATO-IAVE2 and its effectiveness in regulating targeted tissue functions.Heart and Stroke Foundation of Ontario, Natural Science and Engineering Research Council of Canada
Examining the impact of applied LEDs and EMFs on biological systems: analysis of photon emission characteristics and cell viability
Get PDFAll living biological systems naturally emit light, a phenomenon commonly referred to as
biophoton emission. This emitted light serves as a valuable source of information about the
inherent properties of the biological system. Notably, alterations in biophoton emission, resulting
from external factors such as electromagnetic fields or exposure to light-emitting diodes, are
readily observable and well-documented. Alterations in photon emission induced by external
applications were initially measured in both malignant (B16-Bl6) and non-malignant (HEK-293)
cell lines. A notable disparity in spectral power emerged between the two groups, specifically at
the emission frequency of 23.4Hz. Subsequent research focused on the B16BL6, introducing an
electromagnetic field (EMF) application for 15 minutes. The application of a time-varying,
frequency-modulated EMF demonstrated a reduction of viable B16-BL6 cells, with significant
effects noted for the LED application. Notably, biophoton emission at the 13Hz frequency
exhibited increased spectral power following LED exposure, and this frequency displayed a strong
correlation with the number of non-viable cells. Expanding the investigation to a different cell line,
MCF7 breast cancer cells, measurements were taken on both wild-type and doxorubicin-resistant
MCF7 cells exposed to either a 40Hz or Thomas EMF application. A substantial reduction in viable
cells was evident after exposure to both 40Hz and Thomas EMF applications. These findings
suggest that external applications not only influence the intensity and frequency of biophoton
emission but changes in both may serve as indicators of future cell viability. Overall, these results
highlight the potential of external applications, such as EMFs or LEDs, as non-invasive therapeutic
tools in the combat against cancer, shedding light on their influence on biophoton emission and
their potential role in predicting and impacting cell viability.Master of Science (M. Sc.) in Biolog
The impact of temperature and pH on lipid production of seasonally bioprospected microalgae
No full textMicroalgae produce economically valuable metabolites that can be used in the renewable energy
and biopharmaceutical industries. In particular, microalgae have been identified as promising lipid
producers, where total quantities and profiles can be enhanced by subjecting microalgal cells to stress
conditions such as temperature and pH.
However, while cultivation conditions can influence the feasibility of mass production of
microalgae, harvesting them from their growth medium remains a significant economic hurdle. Therefore,
this thesis initially presents a literature review of available harvesting methods and their associated costs.
The review is followed by a study on bioprospected microalgae from various industrially impacted
aquatic environments. The thesis also examines factors impacting lipid production on microalgae
bioprospected over a year and investigates the effect of exposure to variations in temperature and pH culture
conditions. The impacts on growth rate, total lipid accumulation and lipid profiles were determined.
It was found that changes in temperature affected microalgal biomass and lipid production more
than changes in pH. However, the samples' lipid profiles varied significantly as a function of both
temperature and pH. Therefore, the economical production of biofuels using microalgae requires a careful
selection of strains to match growth conditions to enhance productivity.Master of Applied Science (MASc) in Natural Resource Engineerin
Genomic and functional responses of lens epithelial cells to acute and fractionated ionizing radiation
No full textThe lens of the eye, a crucial component in focusing light onto the retina, plays an integral role in our ability to see clearly. Cataracts, defined as the clouding of the lens, can significantly impair vision and, in severe cases, lead to vision loss. This condition, affecting millions worldwide, has been studied extensively to understand its causes and develop preventive measures. One of the known causes of cataract formation is ionizing radiation (IR). Notably, recent recommendations from international regulatory bodies suggest that the threshold radiation dose for cataract formation is lower than previously thought, at an absorbed dose of just 0.5 Gy from low linear energy transfer (LET) radiation. Despite this, the exact mechanisms behind radiation-induced cataracts remain unclear, necessitating further research in this field. This thesis explores the impact of acute and fractionated ionizing radiation on the lens of the eye, concentrating on genomic and functional alterations, to gain a deeper understanding of the causes of radiation-induced cataractogenesis. First, we focused on uncovering acute radiation-induced changes in a lens epithelial cell (LEC) cell line. X-ray irradiation at 0.25 Gy significantly affected cell function, reducing adhesion, initially decreasing proliferation followed by an increase, and stimulating migration at both 12 hours and 7 days post-irradiation. Gene expression analysis indicated the involvement of FGF2, MAPK1, TGFB2, PDGFD, IGF1, MMP9, ITGA5, ICAM1, and CDH2. A non-linear dose response suggested a threshold around 0.25 Gy. Next, we examined functional changes in cultured LEC following fractionated radiation exposure. Exposure to 0.25 Gy significantly affected proliferation and migration over 14 days, peaking at 7 days. High-dose fractionated irradiation contrarily reduced proliferation and migration rates. Transcriptomic analysis revealed dose-dependent gene expression patterns and highlighted biological processes like cell migration and differentiation. Upstream regulator analysis identified TWIST1, BMP2, and NR2F2 as key regulators, elucidating radiation's impact on cellular signaling pathways. Finally, we explored the effects of acute radiation (0.25 Gy and 2 Gy) on embryonic stem cell- derived lentoid bodies over 48 hours using transcriptomic analysis, which identified dose- and time-dependent gene expression changes. At 0.25 Gy, the most significant changes occurred 24 hours post-exposure, while at 2 Gy, they peaked at 48 hours. Gene ontology analysis emphasized impacts on cell fate, developmental processes, migration, and adhesion. Overall, this thesis further elucidates the complex biological response of LEC to acute and fractionated ionizing radiation using both cell line and organoid models. This research helps to further our understanding of the mechanisms behind radiation induced cataracts, which can be used in determining biologically relevant radiation protection standards and assisting in developing mitigation strategies
Exploring Africentric and black feminist approach integration into a mainstream youth mental health organization
No full textThis paper describes my efforts, through an advanced practicum, to identify and address
existing gaps in culturally safe mental health services for African, Caribbean, and Black (ACB)
communities in Canada, and at Compass (a youth mental health agency in Sudbury, Ontario).
These gaps are exacerbated by systemic racism and the Eurocentric approaches typically used in
mental health services. Community experts, clinicians, and individuals with expertise in equity,
diversity, and inclusion (EDI) were consulted to ensure guidance from diverse voices and
perspectives. I engaged Compass as an organization in evaluating their readiness to integrate
Africentric practice perspectives, and I consulted community experts for their input into the
process of integrating Africentric perspectives within Compass.
The project underscores the significance of client-centered mental health care. Guided by
the African Shona proverb, "Muzivi wenzira yeparuware ndiye mufambi wayo" (one who knows
a path over a dwala /rock is the one who walks it), the project's philosophy highlights the
expertise embedded in lived experiences. In collaboration with Compass staff and leadership,
training and recommendations were co-designed to integrate Africentric and Black feminist
approaches, fostering transparency, inclusion, and co-creation. Literature regarding key practice
approaches commonly utilized at Compass was examined with an eye to identifying the
limitations and congruencies of these approaches with Africentric practice, and adaptations
toward greater congruence are recommended.
Broaching, a key approach to connecting with clients when addressing issues such as
racial trauma, was explored in relation to its use in Africentric practice. Africentric approach to
Cognitive Behavioural Therapy was coined as an approach that aligns with Ubuntu's principles, a
set of values derived from numerous African cultures; principles emphasizing interconnectedness
and collective well-being. The project aimed to identify areas in mental health for integrating
Africentric and Black feminist approaches, empowering clients, enhancing trust, and promoting
enriched outcomes through collaborative, culturally informed mental health practices.Master of Social Work (MSW
A community-centric proposal for affordable housing in South Parkdale, Toronto
Get PDFNeoliberal commodification has undermined the
consideration of housing as a basic human right while also
contributing greatly to the current housing crisis in Canada.
To meaningfully address the lack of affordable housing
nationwide, this thesis focuses on the challenges and
opportunities in Toronto, the country’s largest city, where
housing is increasingly inaccessible to many. Drawing on
literature from the disciplines of architecture, urban
planning, sociology, and economics, this thesis analyzes
multiple housing strategies, identifying opportunities
within them to propose a place-based hybrid model. When
deployed, long-term affordability can be achieved while
strengthening community cohesion and identity. Ultimately,
this thesis puts forth a set of design objectives and an
economic implementation plan for a place-based mixed-
use development that provides affordable housing and
amenities in the culturally and socioeconomically diverse
neighbourhood of South Parkdale in Toronto, Canada.Master of Architecture (M.Arch