VictorJuiz/thesis huggingface dataset:
Pharmacogenetic Inhibition of the Subcoeruleus Region Influences REM Sleep and Cataplexy in Narcoleptic Mice
Keywords: Sleep
REM Sleep
subcoeruleus
cataplexy
narcolepsy

Introduction: Cataplexy - the sudden involuntary loss of skeletal muscle tone – is a defining feature of narcolepsy. The current study aimed to determine if cataplexy is influenced by direct manipulation of REM sleep circuitry. We did this by pharmacogenetically inhibiting the REM sleep center, subcoeruleus (Sub-C). Methods: Inhibitory DREADD (hM4D-Gi) was bilaterally targeted to the Sub-C in hypocretin knockout mice (n=7). Intraperitoneal administration of clozapine-n-oxide was used to inhibit Sub-C cells expressing hM4D-Gi. Electrophysiological and behavioral criteria were used to characterize cataplexy and REM sleep. Results: Sub-C inhibition increased REM sleep and cataplexy amounts (p<0.05). Sub-C inhibition increased time spent in cataplexy amounts by increasing the number of cataplexy attacks (p<0.05). This intervention triggered increases in basal muscle tone during REM sleep, but had negligible effects on muscle tone during cataplexy (p>0.05). Conclusion: Pharmacogenetic manipulation of the Sub-C suggest that REM sleep and cataplexy are mediate by similar neural mechanism.
The Role of Syk in Airway Hyperresponsiveness and Remodeling in House Dust Mite Induced Murine Models of Allergic Airways Inflammation
Keywords: Allergic Airway Inflammation
Airway Hyperresponsiveness
House Dust Mite
Murine Model

Spleen tyrosine kinase (Syk) plays a critical role in regulation of immune and inflammatory responses. This thesis investigated the role of Syk in the development of the asthma phenotype in acute and chronic mouse models of allergic airways inflammation. Airway hyperresponsiveness (AHR) to methacholine and inflammation increased significantly in HDM-induced compared with the saline control mice. We demonstrated that in vivo inhibition of Syk by selective Syk inhibitors, and genetic deletion of Syk using conditional Syk knockout mice attenuated AHR despite of inflammatory cell influx in the lung. Histological analysis showed airway remodeling in the chronic model, which was attenuated to some degree by deletion of Syk. This study identified a role of Syk in airway hyperresponsiveness and remodeling without significantly affecting leukocyte recruitment in HDM model of airways disease. My results support the improvement of therapeutic strategies in asthma by targeting the Syk pathway.
Characterization of an Iron-Sulfur Binding Protein in the Tail Tip Complex of Bacteriophage Lambda
Keywords: bacteriophage
lambda
iron-sulfur cluter
protein assembly

The assembly of λ tail requires the action of 11 gene products which must interact in an organized fashion to assemble infectious tail particles. GpL is an essential protein for the formation of the tail tip complex and necessary for the assembly of λ tail. The work described here has shown that gpL and its homologues contain two domains where the C-terminal domain coordinates an oxygen-sensitive [4Fe-4S] 2+ cluster using 4 highly conserved cysteines. This is the first report of a bacteriophage morphogenetic protein to coordinate a [4Fe-4S]2+ cluster. Through two individual cysteine mutants, C184A and C228A, it was determined that these mutant proteins coordinate a [2Fe-2S]2+ cluster also using 4 cysteines; the fourth cysteine being non-conserved. λ tails assembled with cysteine mutant gpL resulted in a 1000-fold decrease in the titer of active tails and tail particles could not be detected by TEM indicating that λ tails cannot be assembled with cysteine mutant gpL. I propose that the coordination of a [4Fe-4S] cluster with the four conserved cysteines maintains a conformation in gpL that can optimally interact with other tail proteins for efficient tail assembly.
Effect of Early Life Vitamin D Supplementation on Bone Development
Keywords: intervention study
early programming
vitamin D
bone development
inflammatory bowel disease
CD-1 mice
IL-10 KO mice

Vitamin D is important for bone development with immunomodulatory effects. This study investigated whether feeding CD-1 and interleukin 10 (IL-10) knockout (KO) dams low (25 IU/kg diet) or high (5,000 IU/kg diet) vitamin D affected bone health of dams as well as their offspring. Offspring were weaned to 1 of the 2 diets and followed to young adulthood. Unlike CD-1 dams, IL-10 KO dams experienced greater femur strength with high vitamin D. CD-1 male offspring had reduced femur neck strength and female offspring had smaller, weaker femurs, and weaker lumbar vertebra 2 (LV2) with high maternal vitamin D. IL-10 KO male offspring had larger femurs and female offspring had stronger femurs when weaned to high vitamin D. Low vitamin D did not adversely impact bone health but the optimal level of dietary vitamin D seems to differ between healthy and inflammatory states.
Elucidating the Role of gpW: an Essential Baseplate Protein in Bacteriophage P2
Keywords: Bacteriophage
Baseplate
Phage P2
gpW
Myophages
Phage Assembly

The long, contractile tails of myophages are the conduit for phage DNA transfer into the bacterial host cell and the most important part of the myophage tail is the baseplate; a complex structure, distal to the phage head. To better understand the structure and function of myophage baseplates, a component of the phage P2 baseplate, gpW was studied. This protein is widely conserved among myophages and is essential for the formation of infectious phage particles. Bioinformatic work confirmed that gpW homologues are found in almost all myophages and in many prophages. Moreover, gpW was shown to be a structural component of the virion; and, using electron microscopy, it was found to be at the top of the P2 baseplate. It was also found that some single residue substitutions can completely disrupt gpW function. Finally, evidence is presented that at least eight different proteins may be required to form intermediate P2 baseplate structures while other proteins may be necessary for the formation of stable baseplate complexes.
Reprogramming Mouse Glioma Stem Cells with Defined Factors
Keywords: cancer
glioma
reprogramming
stem cells
iPS

This thesis shows that p53-deficient mouse glioma brain tumour stem cells (BTSCs), which fail to express pluripotency factors, can be reprogrammed with specific transcription factors to generate iPS cell lines (GNS-iPS) expressing endogenous pluripotency factors (Nanog, Oct4, and Rex1). GNS-iPS cell lines formed embryoid bodies (EBs) in vitro and undifferentiated growths in vivo that phenotypically did not resemble tumours derived from non-reprogrammed BTSCs. EBs formed from one GNS-iPS cell line expressed markers of mesoderm, endoderm, and ectoderm. Tumours produced from GNS-iPS cells had reduced astrocytic marker (GFAP) expression compared to those generated from control iPS cell lines or non-reprogrammed BTSCs. Preliminary results suggest that the reprogrammed cells can be re-differentiated into cells that show neural precursor phenotype. These findings suggest that BTSCs can acquire aspects of the pluripotent state with a defined set of transcription factors, opening the door for further exploration of reprogramming strategies to attenuate the cancer phenotype.
Repulsive-force Electrostatic Actuated Micromirror for Vector-based Display Systems
Keywords: Micromirror
Repulsive-Force
Electrostatic Actuator
Vector Display

This thesis presents the design and development of a novel two-axis micromirror utilizing electrostatic, repulsive-force rotational actuators for laser scanned vector display systems. The micromirror consists of a 1.0 mm reflective mirror plate that can be rotated at high speeds to steer a laser beam to generate images. Fabricated using PolyMUMPs, the micromirror is operated in a non-resonant mode between 0 V and 200 V and can achieve a maximum optical scanning angle of ±2.6° in each axis with a settling time as fast as 2.75 ms and a first resonant frequency of 1400 Hz. Open-loop control methods were developed for image correcting and improving image quality. The micromirror was integrated into a portable, handheld vector display device which included designing and developing driving circuits, device firmware, mechanical components and optical components.
SLIT2 Prevents Renal Ischemia Reperfusion Injury in Mice
Keywords: acute kidney injury
ischaemia-reperfusion injury

The Slit family of secreted proteins act as axonal repellents during embryogenesis. Slit2 via its receptor, Roundabout-1, also inhibits chemotaxis of multiple leukocyte subsets. Using static and microfluidic shear assays, we found that Slit2 inhibited multiple steps required to recruit circulating neutrophils. Slit2 blocked capture and firm adhesion of human neutrophils to and transmigration across inflamed primary vascular endothelial cells. To determine the response of Slit2 in renal ischemia reperfsuion injury, Slit2 was administered prior to bilateral renal pedicle clamping in mice. This led to significant decreases in both renal tubular necrosis score and neutrophil infiltration. Administration of Slit2 also prevented elevation of plasma creatinine following injury in a dose-dependent manner. Furthermore, administration of Slit2 did not increase hepatic bacterial load in mice infected with L.monocytogenes infection. Collectively, these data demonstrate Slit2 as an exciting therapeutic molecule to combat renal ischemia reperfusion injury without compromising protective host innate immune functions.
A Fault-tolerant Strategy for Embedded-memory SoC OFDM Receivers
Keywords: Fault-Tolerance
Embedded-Memory
System-on-Chip
Baseband Signal Processing

The International Technology Roadmap for Semiconductors projects that embedded memories will occupy increasing System-on-Chip area. The growing density of integration increases the likelihood of fabrication faults. The proposed memory repair strategy employs forward error correction at the system level and mitigates the impact of memory faults through permutation of high sensitivity regions. The effectiveness of the proposed repair technique is demonstrated on a 19.4-Mbit de-interleaver SRAM memory of an ISDB-T digital baseband OFDM receiver in 65-nm CMOS. The proposed technique introduces a single multiplexer delay overhead and a configurable area overhead of M/i bits, where M is the number of memory rows and i is an integer from 1 to M, inclusive. The proposed strategy achieves a measured 0.15 dB gain improvement at a 2e-4 Quasi-Error-Free (QEF) BER in the presence of memory faults for an AWGN channel.
Organogenesis in Vitro under Altered Auxin Signaling Conditions
Keywords: auxin signaling
auxin
cytokinin
auxin response factors (ARFs)
callus
de novo organogenesis
shoot regeneration
MONOPTEROS (MP/ARF5)
NON-PHOTOTROPHIC HYPOCOTYL4 (NPH4/ARF7)
Arabidopsis thaliana

The ratio of auxin to cytokinin determines de novo organogenesis in plants. Relatively little is known about the effect of genetically altered auxin signaling on in vitro organogenesis. Here, callusogenesis, shoot, and root formation were studied in loss- (LOF) and gain-of-function (GOF) alleles in two phylogenetically related Auxin Response Factors (ARFs), MONOPTEROS (MP/ARF5) and NON-PHOTOTROPHIC HYPOCOTYL 4 (NPH4/ARF7). Reduced MP activity greatly diminished shoot regeneration, and partially diminished callusogenesis and root formation. LOF in NPH4 strongly decreased callusogenesis, and mildly decreased shoot and root regeneration in particular categories of explants. By contrast, organogenesis responses were strongly increased in aerial explants carrying the GOF transgene dMP. Thus, both MP and NPH4 seem to act as positive regulators of certain organogenesis processes and the GOF dMP transgene may be of interest for stimulating organogenesis in plant species with poor regeneration properties. Also, organogenesis in vitro may reveal unknown developmental ARF functions.
Mechanisms of Action and Relative Efficacy of Glucocorticosteroid Treatment in Ameliorating Immune Thrombocytopenia Induced by Anti-platelet GPIbα Versus GPIIbIIIa Immune Responses
Keywords: Immune thrombocytopenia (ITP)
GPIIbIIIa
GPIbα
Glucocorticosteroids

Immune thrombocytopenia (ITP) is an autoimmune disorder, mediated mainly by autoantibodies against platelet glycoprotein GPIIbIIIa and GPIbα resulting in enhanced platelet destruction. Decreased platelet production and cellular immunity also contribute to ITP. GPIIbIIIa and GPIbα are distinct platelet receptors. Previous studies suggested that anti-GPIbα (versus anti-GPIIbIIIa)-mediated ITP is less responsive to IVIG therapy. However, little information is available whether antibody specificities also dictate efficacy of Glucocorticosteroids (GC), which are the first-line ITP treatment. Here, I first induced ITP in mice by passive administration of anti-GPIbα or anti-GPIIbIIIa antibodies. Results suggest GCs were more effective at amelioration of anti-GPIIbIIIa-mediated thrombocytopenia. I repeated this observation in an active ITP model, in which splenocytes from wild-type platelet immunized GPIbα-/- or GPIIIa-/- mice were engrafted into wild-type mice, which developed ITP. Thus, I established new murine models of ITP for GC therapy and demonstrated that anti-GPIbα-mediated thrombocytopenia may be less responsive to GC therapy.
A Continuous Flow Microwave Reactor for Organic Synthesis
Keywords: Microwave Reactor
Organic Synthesis

Microwave reactors are important tools in chemical synthesis, as they can lead to unprecedented reductions in reaction times and improved reaction yields. In order to scale-up the technology for greater throughput and industrial application, reactor types are moving from batch to continuous flow reactors. This research designed, built, verified and modeled a continuous flow microwave reactor. The reactor could operate under high temperature/high pressure conditions, and was connected to in-line gas chromatography/mass spectrometry, for real time sample analysis. Specifically, a pressure device was developed to enable the reactor to run under high pressure conditions (< 1100 psi) without the use of a conventional back-pressure device. The reactor design was verified using two chemical reactions, and an in-line analytic apparatus was developed to assess the potential for reactor operation with in-line GC/MS. Additionally, a computational fluid dynamic model was developed to better understand the heat and mass transfer inside the reactor.
Consensus on Access to Mental Health Services by Children and Adolescents in Antioquia, Colombia
Keywords: Access to mental health services
Children and adolescents
Antioquia
Colombia
Delphi study

Few mental health studies have explored the prevalence of disorders, risk factors, and availability of services in Antioquia, especially in urban children and adolescent populations. However, access studies have never been developed. Despite growing interest in access, researchers, bureaucrats and interest groups have not come to any consensus about which specific factors may be considered in order to improve access for children and adolescents, especially in provinces with high levels of violence, displacement and inequality. This thesis aims to generate such a consensus among a diverse group of mental health stakeholders around Antioquia. Consensus suggests that predisposing, enabling, need and behaviour factors simultaneously influence access. Additionally, social capital is the resource upon which several mental health programs focus for the development and promotion of mental health services. Finally, stakeholders have identified effectiveness criteria that should be used to evaluate their efficacy as a network in order to improve their work.
Evaluation of an Exhaust Gas Mixing Duct for Off-road Diesel After-treatment Systems Using Numerical Methods
Keywords: aftertreatment
Exhaust gas mixing

Due to strong motivation to reduce costs and increase performances of stationary diesel after-treatment systems, computational modeling has become a necessary step in system design and improvement. A unique mixing duct typified by significant changes in scale and strong flow curvature was evaluated for its potential to improve flow distribution across the SCR catalyst inlet face. The flow dynamics were investigated with a steady three-dimensional turbulence model and detailed chemistry was studied separately using a one-dimensional channel reactive flow model. Aqueous urea injection was modeled using Discrete Phase Modeling. The mixing duct performance relative to reactor dimensions and engine loads is discussed. The Impact of injector positions was studied using massless particle tracking. A total of three geometries were evaluated using a Uniformity Index of the ammonia-to-NOx feed ratio. It was found that a higher mixing duct height to inlet diameter ratio yielded better mixing.
Exacerbated Cardiac Fibrosis in Apelin-deficient Mice post Myocardial Infarction is Associated with Vimentin and MicroRNA-378
Keywords: Myocardial Infarction
Apelin
Vimentin
MicroRNA
Cardiovascular disease
Cardiac Fibrosis

The Apelin-APJ system is transiently up-regulated in murine models of cardiac dysfunction. We have previously shown that Apelin-deficient mice subjected to aortic constriction suffer from severe fibrosis. In turn, we hypothesized that Apelin deficiency will also exaggerate the fibrosis phenotype post experimental myocardial infarction, associated with changes in fibroblast cell activity. Apelin-deficient and wildtype mice were randomly subjected to sham operation or left coronary artery ligation. Apelin deficiency worsened cardiac functionality, enhanced fibrosis-related gene expression and morphology, and enhanced vimentin intermediate filament expression, which may be involved in increasing fibroblast proliferation. MicroRNA target prediction softwares predict that apelin and vimentin 3 ’UTRs are potential targets of microRNA-378 regulation, and were confirmed with Luciferase reporter assays and western blot. Apelin up-regulation may be a useful strategy for attenuating unfavorable fibrosis through down-regulating vimentin-mediated adverse fibroblast activity. MicroRNA-378 regulation may be partly responsible for changes in apelin and vimentin expression.
Modulation of Multidrug Resistance Phosphoglycoprotein in the Mouse Placenta and Fetal Brain by the Selective Serotonin Reuptake Inhibitor Sertraline and Maternal Bacterial Infection
Keywords: Reproduction
Development

Multidrug resistance phosphoglycoprotein (P-gp) is expressed in the placenta and fetal blood-brain barrier (BBB) and plays a critical role in reducing fetal accumulation of xenobiotics. In other tissues, P-gp activity is inhibited by selective serotonin reuptake inhibitors (SSRIs) and by lethal doses of LPS modeling a bacterial infection. However, nothing is known with respect to the effects of SSRIs or nonlethal infection on P-gp activity in the placenta or fetal tissues. In the studies presented in this thesis, we hypothesized that (1) the SSRI sertraline and (2) a nonlethal maternal bacterial infection would decrease P-gp activity in the placenta and fetal BBB. The first study shows that sertraline affects P-gp activity at these barrier sites in a tissue-specific manner. The second study shows that nonlethal infection does not significantly affect P-gp activity at either site. However, nonlethal infection may still influence substrate biodistribution by altering hepatic elimination of these substrates.
Canadian Mining Companies, Social Disclosure and Extra-Territorial Human Rights Obligations
Keywords: securities disclosure obligations
human rights violations

The liability of companies for extra-territorial human rights violations does not solely arise from human rights statutes and traditional tort law approaches, but also from the corporate and securities law domains. Securities law requires that public companies disclose any high risk activity that the company is involved in, to the extent that it may affect the viability of the corporation, and this includes possible human rights violations. Management decisions in the field of Corporate Social Responsibility must concern the long-term viability of a company, and therefore accommodating, to the extent possible, the demands of stakeholders – be they traditional shareholders, responsible shareholders, or affected communities. This thesis will analyze the legal obligations triggering such corporate decisions, as well as the industry trends which inform them. The focus will be on Canadian public mining companies.
Role of Spongiotrophoblast VEGFA during Pregnancy
Keywords: VEGFA
spongiotrophoblast
placenta
pregnancy
cardiovascular

The role of placental VEGFA in placental development and maternal pregnancy adaptations is unknown. In this thesis, one or both copies of Vegfa was knocked out from the placental spongiotrophoblast region using a mouse Cre-loxP system. Surprisingly, in pregnancies carrying 100% conceptuses with a single deletion of Vegfa from the spongiotrophoblast layer, maternal circulating VEGFA increased by 20% accompanied by a 15% decrease in arterial pressure while no impairment in embryo growth was found. In pregnancies carrying 50% conceptuses with both copies of Vegfa deleted from spongiotrophoblast, 17% of conceptuses had been reabsorbed by late gestation suggesting a function for spongiotrophoblast VEGFA in sustaining early pregnancy. In conclusion, spongiotrophoblast VEGFA affects maternal function during pregnancy but the exact mechanism remains to be defined.
Pathogenesis of Fetal and Neonatal Immune Thrombocytopenia: Role of Anti-Beta3 Integrin Antibodies in Vascular Injury and Angiogenesis
Keywords: Fetal and neonatal immune thrombocytopenia
platelets
integrin
angiogenesis

Fetal and neonatal immune thrombocytopenia (FNIT) is a severe bleeding disorder which results from fetal platelet destruction by maternal antibodies against platelet antigens, including GPIIbIIIa (αIIbβ3 integrin) and GPIbα. β3 integrin is also expressed by angiogenic endothelial cells (ECs) and is required for angiogenesis. Therefore, we investigated whether anti-β3 antibodies in FNIT cross-react with blood vessels of the fetus/neonate and contribute to pathogenesis. Antibodies to GPIbα were used as controls. To mimic human FNIT, β3 integrin- or GPIbα-deficient female mice were immunized with wild-type platelets and bred with wild-type male mice. Pups in both groups had thrombocytopenia but intracranial hemorrhage was only observed in anti-β3-mediated FNIT. Anti-β3-mediated FNIT pups had increased apoptosis in the brain and impaired vascularization of the brain and retina. In addition, anti-β3 sera inhibited proliferation and vascular-like tube formation by ECs in vitro. Therefore, anti-β3 antibodies in FNIT likely impair angiogenesis in the developing fetus/neonate.
Proteomics of Thyroid Carcinoma: Detection of Potential Biomarkers of Aggressive and Non-aggressive Subtypes
Keywords: Thyroid
Oncology

In search of thyroid carcinoma biomarkers, proteins secreted by thyroid cancer cell lines, papillary-derived TPC-1 and anaplastic-derived CAL62, were analyzed using liquid chromatography-tandem mass spectrometry. Of forty six high-confidence identifications, six proteins were considered for verification in thyroid cancer patients’ tissues and blood. The localization of two proteins, nucleolin and prothymosin-alpha (PTMA), was confirmed in TPC-1 and CAL62 by confocal microscopy and immunohistochemically in xenografts of TPC-1 cells and human thyroid carcinomas. Increased nuclear and cytoplasmic expression of PTMA was observed in anaplastic carcinomas compared to normal thyroid tissues, papillary and poorly differentiated carcinomas. Importantly, six proteins were detected in thyroid cancer patients’ sera, warranting future analysis to confirm their potential as blood-based thyroid cancer markers. Herein we demonstrate the ability of secretome analysis of thyroid cancer cell lines to identify proteins that may be studied for application in management of thyroid carcinomas upon future validation.