VictorJuiz/thesis huggingface dataset:
Survival, stroke recurrence and functional outcome after lacunar stroke

Obiectives. (1) To assess stroke recurrence, survival and functional outcome in patients with lacunar stroke. (2) To determine if there are differences between patients with first and recurrent stroke and between patients with and without an embolic source. Methods. A cohort of 147 patients with lacunar infarction admitted between January 1, 1993 and December 31, 1996 was followed until March 2000. Linkage with the Canadian Institute for Health Information (CIHI) discharge abstract identified recurrent stroke. Linkage with the Vital Statistics database identified deaths. Functional outcome was assessed using the Barthel Index. Results. Survival at 5.5 years was 72 +/−8%. Stroke-free survival at 5.3 years was 75 +/−14%. Functional independence (Barthel = 100) was identified in 63% of patients contacted. Patients with an embolic source had shorter survival times (p < 0.05). Patients with recurrent stroke had worse functional outcome (p < 0.001). Conclusions. While patients with lacunar infarction have a high chance of independence and a low risk of stroke recurrence, survival was worse in patients with an embolic source and functional outcome was worse in patients with recurrent stroke.
Experiments involving the transmission of layered video over a local ATM network

In this thesis we investigate the feasibility of transmitting layered video over a local ATM network. Two layered video schemes were looked at: subband coded layered video and MPEG-2 SNR scalable layered video. In both cases the video was transmitted as a constant bit rate (CBR) base layer and an unspecified bit rate (UBR) enhancement layer, we then introduced background traffic (both CBR and UBR) in order to determine their effect on the layered video in terms of delay, jitter and loss. The results obtained for the subband coded video were quite promising, with competing cross traffic in the network having very little effect on base layer jitter or loss. We also found that specifying the cell delay variation tolerance (CDVT) was a factor in preventing base layer loss. Losses in the enhancement layer occurred only when total utilization exceeded 100%, also maintaining synchronization between the two layers did not prove to be problematic even at very high network utilization. Similar results were obtained for the MPEG-2 scalable video, however due to the much higher bit rates in this case, we found maintaining synchronization between the two streams to be more difficult.
The role of incretin hormones in glucose homeostasis

Incretins are hormones that are released from the gut in response to nutrient ingestion and act to enhance glucose-stimulated insulin secretion. The two major peptides which have been identified as incretin hormones are glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). Previous glucoregulatory studies using receptor knockout mice models suggest that the role of GIP is restricted to that of an incretin, whereas GLP-1 also exhibits non-incretin effects. However, studies with genetically-modified mice can be complicated by compensatory adaptive changes. To avoid this possibility, we assessed the incretin and nonincretin actions of GIP and GLP-1 in wild-type mice using the GLP-1 receptor antagonist exendin(9-39) and immunopurified anti-GIP receptor antisera to antagonize GLP-1 and GIP action, respectively. Our results indicate that GLP-1, but not GIP, plays an important role in regulating blood glucose levels in mice in a manner independent of oral nutrient ingestion. In addition to its role as an incretin, GLP-1 contributes to blood glucose lowering through several different mechanisms and thus its therapeutic value as a treatment for diabetes is currently under investigation. However, GLP-1 is rapidly catabolized by dipeptidylpeptidase IV (DPP-IV) and therefore has a short plasma half-life, which may, in turn, limit its therapeutic potential. Inhibition of DPP-IV activity could thus provide a means to extend the half-life of GLP-1. However, DPP-IV may also act upon other substrates important for glucoregulation. To investigate this possibility, we examined the effects of DPP-IV inhibition in GLP-1 receptor knockout mice. Our results suggest that in addition to GLP-1, other substrates are involved in the DPP-IV-mediated regulation of blood glucose control. Exendin-4 is a potent GLP-1 receptor agonist that was originally purified from lizard venom and is currently being evaluated in clinical trials as a treatment for diabetes. Limited information is available regarding the long-term effects of exendin-4 treatment 'in vivo'. To assess the physiological effects of chronic exendin-4 expression 'in vivo', we have generated transgenic mice in which exendin-4 expression is under the control of an inducible promoter. Our data indicate that sustained elevation of circulating exendin-4 has both predicted and unanticipated effects on GLP-1 receptor-dependent physiological end points.
Effects of the inflammatory response to HEMA-MMA microencapsulated cell survival, studies in immunocompromised mice

A significant increase in survival of HEMA-MMA encapsulalted Chinese Hamster Ovary cells was observed in immunocompromised mice compared to normal Balb/c mice, Immune and inflammatory issues have limited the 'in vivo ' utility of encapsulated xenografts for protein delivery. Although encapsulated cells survive in immunocompromised mice due to the lack of T cells, similar macrophage activation profiles were observed in both types of mice, suggesting an alternative pathway from macrophage activation to capsule rejection. Since CHO cells remained viable in immunocompromised mice even after three weeks, this suggested an important role for T cells, and an indirect role for macrophages, in capsular rejection. On the other hand, differences in tissue reaction and IL1-ß activity were observed. Less pronounced collagen deposition was observed in immunocompromised mice and IL1-ß activity was much lower. Our results suggest that the cross talk between T cells and the macrophage is important in eliciting encapsulated xenograft rejection.
SspB cysteine protease of Staphylococcus aureus promotes detachment of human keratinocytes and degrades fibronectin and vitronectin

SspB cysteine protease of 'S. aureus' is coded for by the 'sspB' gene, the second open reading frame of the ' ssp' operon in which it is preceded by the 'sspA' gene (V8 protease) and followed by the 'sspC' gene. The 40 kDa precursor form of SspB (p-SspB) was expressed alone and in tandem with the sspC gene. In the presence of SspC, p-SspB showed greater activity by gelatin zymography. This may indicate a chaperone function for SspC. Purified p-SspB was processed by V8 protease to the mature, 22 kDa m-SspB. Purified m-SspB was shown to promote keratinocyte detachment. Also, m-SspB was shown to cleave fibronectin and vitronectin but not BSA, IgG or fibrinogen. These results may demonstrate that SspB is expressed as a zymogen, that is converted to an active protease, m-SspB, and that m-SspB may have an important virulence function in ' S. aureus' pathogenesis through proteolysis of host proteins.
Characterization of anaerobic dechlorinating enrichment cultures maintained on different chlorinated ethenes

An anaerobic mixed microbial culture previously enriched from soil and groundwater contaminated with trichloroethene (TCE) was divided into four subcultures amended separately with either perchloroethene (PCE), TCE, ' cis'-dichloroethene ('cis'-DCE) or vinyl chloride (VC). The sustained and complete conversion of chloroethenes, including VC, to ethene was observed in all subcultures. Differences in rates and community composition developed between the different subcultures, including the loss of the VC enrichment culture's ability to dechlorinate PCE. Results of denaturing gradient gel electrophoresis using 16S ribosomal RNA (rRNA) genes indicated that three different organisms, all related to 'Dehalococcoides ethenogenes', were present in all four subcultures. Molecular cloning and sequencing of 16S rRNA genes identified further similarities and differences in community composition between the VC and TCE enrichment subcultures. Due to biases in DNA amplification, further molecular cloning efforts are required to completely characterize the enrichment subcultures.
An examination of intra-secondary school conflicts in complex emergencies, the case of Sierra Leone

This study describes how selected teachers and students in secondary schools in urban Sierra Leone perceive and manage interpersonal conflicts during complex emergencies, with a view to identifying the challenges for building a culture of peace and for further research. Using a qualitative research paradigm, the study examines how the interview subjects understand the meaning of interpersonal conflict and its effects on student-student and student-teacher relationships. The study also examines what types of conflicts the interview subjects experience in school, the root causes of these conflicts and how they respond to them. The data for this study were collected using semi-structured and unstructured interviews, documentary analysis, and the researcher's personal observations and lived African experiences. Key concepts such as 'the meaning of intra-school conflicts, adult education, peace, peace education, structural violence' and 'structural conflict, non-violence' and 'complex emergency,' used in the study are also defined. Due to the relatively limited research on how African students and teachers perceive and manage inter-personal conflicts, the study uses conceptual frameworks mostly from a North American context and elsewhere. The data reveal that nearly all the interview subjects perceive conflict from a negative perspective. Very few of them perceive conflict as having any positive values. The study indicates that interview subjects experience conflicts that are mostly related to basic human needs, particularly--adequate food, safe drinking water, adequate school supplies, conducive classrooms, respect for human rights, gender equality, peaceful relationships, safe school environment and reasonably good and regular teachers' salaries. According to the study, most of the interview subjects' respond to conflict violently. Very few use non-violent responses. In order to build a culture of peace particularly in the secondary schools in Sierra Leone, the study proposes the integration of a Transformative Peace Education (TPE) Programme in the school curriculum. The study suggests thematic areas for TPE including, 'critical awareness building on gender equality, anti-tribalistic education, democracy' and 'human rights' and 'training on constructive conflict resolution'. The study highlights some of the major challenges of TPE, raises questions for further research and concludes with a prayer for enlightenment for all Sierra Leoneans.
Design and construciton of a prototype multispectral fluorescence guidance system for use in brain cancer treatment

In this work, the concept of an intra-operative multispectral fluorescence guidance (MFG) system was implemented. The photonic-system design was tuned by literature studies, previous experiments, and clinical requirements. The resultant MFG system could capture spectrally resolved fluorescence image at 4 wavelengths in the visible spectrum using a thermo-electrically cooled CCD, as well as fluorescence spectra from a small, localized area (diameter $\le$ 1mm) of the object using a fiber-optically coupled spectrograph, covering from 480nm to 720nm. The instrument had a long working distance of 55 to 60cm, a field of view of 3.3cm x 2.5cm, a depth of focus larger than 1cm, and lateral spatial resolution of 0.15mm. It was demonstrated that the MFG system could detect sub-millimeter size targets with clinically relevant concentrations of Photofrin, and could measure the photobleaching of Photofrin, in an aqueous brain tissue phantom under simulated photodynamic therapy (PDT) conditions. In vivo measurements of squamous epithelial cancer in a hamster cheek pouch model also demonstrated the MFG system's ability to distinguish cancerous tissue from normal tissue using drug-induced fluorescence. The MFG system will be used in a current clinical trial of PDT in the brain at the completion of the project.
Pyruvate dehydrogenase complex, correlation between structure and function

Human PDH complex deficiency is an extremely heterogenous disease in its presentation. Very little correlation between clinical course and molecular characteristics has been established so far. In order to more accurately define the structure of the complex, mutational analyses were performed on its two components, PDH-E1Ã and protein X. A series of PDH-E 1Ã deletion mutants was constructed and expressed in a cell line with zero PDH complex activity due to a null E1Ã allele (the [pi] 0 cell line). Sequential deletion of the C-terminus by 1,2,3 and 4 amino acids resulted in PDH complex activities of 100, 60, 30 and 14% compared to wild-type E1Ã expressed in PDH complex deficient cells. In addition the somatic and the testis-specific PDH-E1Ã human isoforms were determined to be biochemically equivalent. Furthermore, a series of PDH-E1Ã, histidine mutants (H63, H84, H92 and H263) was constructed and expressed in the [pi]0 cell line. H63 and H263 were shown to be essential for the PDH complex activity, while H92 was implicated in the PDH-E1Ã2ß2 heterotetramer formation and/or stability. A novel PDH-E1Ã mutation R141L was characterized in a male patient and it was found in about 75% of the studied DNA derived form various tissues (fibroblasts, liver and muscle). This scenario would indicate a case of E1Ã somatic mosaicism. The R141L mutation is a severe one and it must have occurred in one of the E1Ã alleles during early embryogenesis. To gain further insight into the nature and function of the domains of the human protein X, two artificially created variants, K37E and S422H as well as the wild-type were expressed in SV40-immortalized protein X-deficient and E2-deficient human skin fibroblasts. The former mutant does not carry the lipoic acid moiety; the latter mutant was designed to investigate the possibility that protein X could exhibit an intrinsic transacetylase activity. None of the expressed protein X variants had an effect on the specific activity of the PDH complex, suggesting that the human protein X plays a purely structural role. A novel syndrome affecting multiple mitochondrial functions was described and localized by microcell-mediated transfer to chromosome 2p14-2p13.
Role of the MAPK in the monocyte/macrophage procoagulant response, implications for fulminant viral hepatitis

Viral fulminant hepatic failure (FHF) is one of the most devastating diseases in clinical medicine, with progression from complete health to death occurring in a matter of days or weeks. Liver destruction is characterized by the dense infiltration of monocuclear cells (monocytes, macrophages and lymphocytes) with subsequent activation of the inflammatory coagulation cascade. We have studied the activation of the coagulation cascade by cells of the monocyte/macrophage lineage under conditions that model the integrin-dependent migration of the cells across the vascular endothelium and into the liver parenchyma, and the reaction of the cells to a viral pathogen known to induce FHF in mice. Tissue factor (TF), one of the chief inducers of coagulation, is expressed on monocytic cells in response to surface integrin crosslinking and following transendothelial migration. Fig-2/fibroleukin, a potent prothrombinase, is expressed on macrophages after infection with Murine Hepatitis Virus Strain-3 (MHV-3). Recent work has suggested that Mitogen Activated Protein Kinases (MAPK) are involved in integrin signaling and the monocyte response to infectious stimuli. We postulated that the ERK and p38 MAPK play critical roles in monocyte migration and the reaction of macrophages to MHV-3. We demonstrated activation of the ERK and p38 MAPK in response to integrin crosslinking, monocyte adhesion to activated endothelial beds, and infection of macrophages with MHV-3. Taking advantage of novel, selective inhibitors of the ERK MAPK pathway and the p38 MAPK (PD98059 and SB203580, respectively) We found that both MAPK modules are essential for the induction of TF in the adhesion dependent response to monocyte transendothelial migration. The p38 MAPK was necessary for fgl-2 expression in response to MHV-3; ERK was necessary for fgl-2 activity. These studies suggest that critical aspects of the monocyte/macrophage response which drives liver destruction in viral FHF are under the control of the ERK and p38 MAPK. Thus, the selective inhibition of these modules may be of use in attenuating the inflammatory damage of viral FHF.
A theoretical investigation of the generation of a spontaneous slow rhythm in hippocampus CA1

Different rhythmic activities in CA1 characterize the neuronal correlates of several behavioral states. Recently, in an in vitro preparation of the whole hippocampus, spontaneous slow rhythms (<4 Hz) similar to the hippocampal EEG seen in behaving animals, have been recorded. Based on the experimental data and by using numerical simulations, we suggest a mechanism in which feedback from populations of synchronized interneurons entrains an increasing and/or more synchronized activity in a spatially dynamic pyramidal cell population. In this scenario, two network properties, i.e. the number of the excitatory cells and the excitability of the interneurons, determine the frequency and robustness of these slow rhythms. Furthermore, using a stochastic phenomenological model, we show that in the face of a stochastic basal activity, these two properties enable the network to differentially amplify/suppress the modal structure of the emergent rhythmic activity, hence, act as a dynamically tunable resonant network.
Smart TCT, an efficient algorithm for supervisory control design

This thesis discusses a new synthesis approach to the supervisory control for Discrete Event Systems (DES). The new approach, named S(mart)TCT after the old CTCT, is much more efficient than the existing synthesis approaches. Using STCT, many practical systems can be synthesized using a personal computer. Besides, it is shown that the number of nodes in the Integer Decision Diagram (IDD) representing a DES can be a better measurement of the complexity of the DES than the number of states. The structural information in a given DES is exploited to help STCT achieve efficient performance. The algorithm is based on one common feature of most practical systems--a large system is almost always built up by synchronizing many small components. In the synthesis process, no synchronization product is computed explicitly and thus there is no need to list the entire state space. The success of our new approach is illustrated with very large versions of existing (small) examples taken from the literature.
Carl Schmitt's concept of the political, Thomas Hobbes and the political theological critique of liberal democracy

This thesis examines Carl Schmitt's political theorizing. Carl Schmitt was one of modern Germany's most influential political theorists. He is most well-known for his work 'The Concept of the Political' which explicated his understanding of politics; the political is most clearly revealed in the distinction between friends and enemies. However, exactly how Schmitt conceived of the decision regarding friend and enemy as paradigmatic for an understanding of healthy politics is problematic. Schmitt presented the friend-enemy distinction in a rhetorically forceful but conceptually unclear manner. This thesis investigates whether one can coherently make sense of Schmitt's "concept of the political" and whether Schmitt's teaching regarding the political can be understood as forming a coherent whole; is there an identifiable basis or perspective which consistently informs Schmitt's thinking about what "the political" is. While there is much to be learned from previous efforts to comprehend Carl Schmitt, for the most part, these efforts have not taken into account his serious moral and theological concerns. Schmitt should be understood primarily as a political theologian; he conceived of history and politics as a field of providential struggle. Schmitt particularly viewed liberalism from such a perspective; he found in liberalism the most extensive rejection of the sovereign status of God in human affairs. In turn, the best way to investigate Schmitt's theorizing is to examine his understanding of Thomas Hobbes. Hobbes' political philosophy is central to Schmitt's theorizing. Schmitt sought to rehabilitate Hobbes as the philosopher who could be employed in comprehending the modern world. However, Schmitt, who originally thought of Hobbes as the philosopher best suited to his own project, was forced to return to Hobbes' positions which seem impious. Ultimately, Schmitt attempted to rescue Hobbes the 'vir probus' whose thinking was devout from the image of Hobbes as the creator of a new "mortal god." The consistency of Schmitt's own theorizing is reflected directly in his thinking about Hobbes. Hobbes' political philosophy is the key to understanding Schmitt's criticisms of modernity and his explication of the political and is the most important test case for investigating the political theological nature of his thought.
Calling the shots, the influence of organized medicine on policymaking in Ontario and California, 1969-2000

The decision by the Ontario and California governments in the 1960s to establish government-sponsored programs of medical care insurance challenged the traditional guild model of medicine that entailed private, solo or small group practice, negotiated payment between physicians and patients on a fee-for-service basis and professional licensing and discipline. This dissertation addresses the question of why physicians have retained more of their policymaking influence under the public health insurance model in Ontario than under the managed care approach of California. It explains the differences in the degree of influence of the medical associations on policymaking by focusing on the importance of interests and institutions (including previous policies) as independent variables. It highlights the ways that these factors alter the structure of opportunities that exist for interest groups to successfully promote their political agendas. Ontario and California were chosen as sites for the comparison because, although they have significant social and cultural similarities, they have developed dissimilar government/society relationships and capacities for state intervention that have affected their health policy outcomes. The central argument of the dissertation is that in Ontario the early decision to establish a governmental health insurance program and the use of policy instruments like the federal spending power and the Canada Health Act helped the state to maintain a relatively stable concertation relationship with the medical profession. The Ontario government and organized medicine have cooperated in long term policy deliberations that have enabled physicians to preserve much of their autonomy and political influence, although they have a lower mean net income than California physicians. In the United States, such devices as the separation of powers and federalism have made it difficult to establish a universal system of publicly funded health care. The dispersal of authority between many state actors and antitrust regulations that prevent physicians from engaging in collective bargaining have led to the development of a pluralist policy network in the California health sector. They have weakened physicians' corporate, clinical, economic and organizational autonomy and dominance by fragmenting their interests in a predominantly managed care environment.