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The HIV-1 Gag p24 protein contains the HLA class-1 B*2705 restricted epitope KK10, responses to which are associated with delayed progression. Data from in vitro proteasomal digestion studies from our group has shown the production of a number of C-terminally extended and truncated epitopes containing KK10, produced in far higher quantities during proteasomal digestion than this “optimal epitope” and that the amount of antigen made in proteasomal digestion is instrumental in determining the development of immunodominance. This work aims to characterise the contribution of these naturally processed epitope forms to the cellular immune response to this region. Further proteasomal digestion studies have shown that the common KK10 intra-epitope escape mutant sequences R132K and L136M have major effects on epitope production by the proteasome and that a range of short peptides containing the N-terminal of the KK10 sequence are produced in large quantities by the proteasome. Recognition of the KK10 epitope forms by HLA B*2705 HIV-1 patients were characterised ex vivo and show recognition of KK10 epitope forms somewhat independent of the presence of KK10 recognition, we also show cross-recognition between KK10 epitope forms by CD8+ T cells, as well as recognition by CD4+ T-cells. TCR from CD8+ T-cells specific for KK10 epitope forms were found to share common features in the HLA binding CDR hyper-variable loops. Structural studies of the HLA B*2705 molecules in complex with the KK10 epitope forms show a shared binding motif at the N-terminus, and to a lesser extent, the C-terminus of the binding groove which may facilitate cross-recognition of complexes. In addition these studies show a potentially novel binding mode for a 14mer peptide, and refolding of truncated KK10 peptides as short as a 4mer with the HLA B*2705 molecule (crystallisation with a 6mer peptide shown). This demonstrates previously unrecognised flexibility of the HLA class-1 to bind and present peptides of different lengths to T-cells. We show that these HLA B*2705 binding-capable truncated peptides do not induce a CD8+ T-cell response in HLA B*2705 HIV-1 patients and may be able to block CD8+ T-cell responses to the KK10 epitope. This might represent a novel form of viral CTL escape. In addition we observe the presence of KK10 flanking mutations in patient sequences and significant associations between the presence of intra-epitope escape mutations, KK10 recognition and patterns of escape in flanking sequences. Finally we note the reduction in binding of KIR3DL1 to KK10 epitope forms relative to the KK10 epitope-HLA B*2705 complex. The presence of HLA B*2705 and KIR3DL1 associate with improved disease course in HIV-1 though the mechanism through which this occurs has yet to be defined.

23/6/2011 Kosterní zbytky v potravě kalouse ušatého 7 jako ukazatele populačních změn drobných savců 1.2 Abstrakt v anglickém jazyce The diploma thesis is called Skeletal Remnants in Diet of Long-eared Owl Asio otus (Linnaeus, 1758) as The Indicators of Fluctuation in Size of Population of Small Mammals in Wintering Place in Kladno-Kročehlavy. The thesis deals with oversight of Long-eared Owl in his wintering site, analysis of his diet, and estimation of population changes in the diet of small vertebrate. It also consists of the estimation of changes in gender of small mammals and in the content of his diet, and of studies morphological traits done on pelvises of males and females of common vole. As part of didactic section there were laboratory exercises completed. The focus was on the analyses of pellets and the assignment of small vertebrates in the diet of Long-eared Owl. The main monitoring was completed in the period of autumn 2009 till the end of winter 2010. The results showed significant changes in the population of small mammals included in the diet of Long-eared Owl could bring new knowledge about population dynamics of small mammals. Another part of monitoring of population of Long-eared Owl was also tramping and ringing. Most of the materials used for this analysis of the diet came from the...

This dissertation examines the wealth effects of bank mergers on bidder, target, and combined firm shareholders for a sample of 785 mergers during the period 1980-2000. The dissertation employs two unique bank event study methodologies to calculate abnormal returns for bidder, target and combined firms. The first methodology is a modified market model that controls for shocks common to the banking industry. The second is an EGARCH (1,1) model that adjusts for the violated regression assumptions of the traditional market model event study. Namely, it controls for the linearity assumption, heteroskedasticity, and the correlation in the error term. The results of both methodologies reveal that target shareholders enjoy significantly positive abnormal returns, whereas the bidder shareholders experience significantly negative abnormal returns. Overall, announcements of bank mergers generate positive wealth effects for the combined shareholders. However, the evidence presented in this dissertation, to some extent, underscores the importance of the choice of models describing stock returns in examining the impact of bank mergers. In addition, when mergers are analyzed to determine the effects of relative size and relative book-to-market values, we find evidence that the relative size significantly affects the target, bidder and combined firm return; method of payment is also found to be significant in abnormal returns. Moreover, we find that the number of bidders affects only the bidder returns, while book-tomarket values are irrelevant factors. Availability Restricted: Release the entire work for campu

Thesis advisor: Bernard O'Brien / This study investigated factors which influenced stable, primary love relationships among twelve lesbian couples who had been together at least fifteen years and had not reared children together. Each participant was interviewed separately in a retrospective, semi-structured interview that assessed the impact of selected factors over the course of the relationship. Each factor was examined to determine its influence in the beginning phase of the relationship (the first 5 years), in the middle phase (5-10 years into the relationship), and most recently (beyond 10 years into the relationship). Interpersonal dynamics as well as the influences of culture, religion, values, finances, and social supports were explored to determine their impact on relationship stability. / Thesis (PhD) — Boston College, 1994. / Submitted to: Boston College. School of Education. / Discipline: Counseling, Developmental Psychology, and Research Methods.

Faculty of Orthodontics School of Health Sciences 81/0315/8 Miltstein@global.co.za / The incidence of relapse following orthodontic treatment has always been of paramount interest to clinicians and research workers. Many investigations have been carried out at various Universities to assess the long-term stability of orthodontic treatment. This study assessed the stability of 31 cases at least ten years out of retention treated by post-graduate students in the Department of Orthodontics at the University of the Witwatersrand, Johannesburg. Associations between certain clinical parameters and postretention relapse were also evaluated. Occlusal changes which had taken place were assessed by evaluating data from models taken prior to treatment and comparing these with similar parameters at the end of treatment and, on average, just less than 13 years following the end of retention. Eleven parameters were recorded and measured according to a scoring system proposed by Sadowsky and Sakols. A total malocclusion score was obtained for each study model by calculating the algebraic sum of all the scores. The total malocclusion scores thus indicated the severity of malocclusion presented by each study model at each period. A further examination of each of the study models was carried out in order to establish the Irregularity Index. The anatomic points at which contact would be made were defined on each surface of the six mandibular anterior teeth. The distance between the contact points of the adjacent teeth were measured using a digital vernier caliper calibrated to the nearest 0,05mm. The sum of these 5 measurements provided the Irregularity Index. Values for mandibular irregularity were then grouped into minimal, moderate and severe categories. v Changes in the intercanine and intermolar widths were correlated with overbite, overjet and anterior mandibular crowding parameters. The study also determined whether the presence or absence of third molar teeth and/or premolar extraction therapy were associated with relapse. At postretention 54.8 percent of the sample displayed some degree of relapse in at least one of the variables studied. However, all of the variables studied showed a greater degree of stability than relapse. Canine relationship showed the most postretention stability, whilst deep bite, overjet and molar relationships showed the least. With a few exceptions, occlusal abnormalities which were considered to be severe at the commencement of treatment demonstrated a high degree of stability following corrective therapy, whereas the relapse of mild to moderate features prior to treatment was not as predictable. The small amount of change noted in intercanine and intermolar widths at all three stages of treatment were not significant predictors of relapse at the 5 percent significance level of the parameters assessed. Furthermore the presence or absence of third molar teeth was not a significant predictor of poor postretention malocclusion score, overjet or overbite. Similarly extraction therapy was not a significant predictor of lower incisor alignment relapse (p=1.0). The mean irregularity index of the whole sample following retention indicated that the lower incisors displayed minimal crowding (2.7 mm). Following at least ten years out of retention, treated cases in the Department of Orthodontics, University of the Witwatersrand, Johannesburg showed a high degree of stability for the parameters assessed.

A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of; Masters of Science in Medicine (Anatomical Sciences) School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg. 2017. / This research studied adult hippocampal neurogenesis in the dentate gyrus of the hippocampus of the Long-Evans rat. Eighteen male Long-Evans rats were exposed to complex enriched environment, the running wheel environment for exercise as single influencing factor and the standard laboratory environment for 28 days. Thereafter the rats were transcardially perfused with 0.9 normal saline followed by 4% paraformaldehyde. The brains were removed and frozen sagittal sections cut at 50 μm. Brain sections were stained with Cresyl violet for cytoarchitecture. Immunohistochemistry and immunofluorescence techniques were employed for the immature neurons with defined processes using the marker doublecortin (DCX), neuronal proliferation marker Ki-67, the synapse marker, synaptophysin and the dendritic spine marker, synaptobrevin. Giemsa staining was used to identify pyknotic neurons followed by counts for DCX, Ki-67, pyknotic positive cells, and volume density of the dentate gyrus. Results indicated a statistically significant increase in brain weight (p=0.5) for the complex enriched group when compared to the running group and control. The typical cytoarchitecture of the hippocampus in rodents was observed with more densely packed granule cell layer in the dorsal limb of the dentate gyrus compared to the ventral limb especially in the enriched group. The Ki-67 immunopositive cell number between groups showed a variable difference with a three-fold increase each between the standard control and exercise, and between the exercise and enriched but a six-fold increase between the standard control and the complex enriched groups. Comparing the DCX immunopositive results, we observed also that the neuronal numbers, structure, dendritic patterns as well as the neuronal arrangement on the dorsal and ventral limbs of the dentate gyrus varied significantly among groups. The apoptotic cell numberusing pyknotic cells, showed the standard control group to have the highest number of cells compared to the exercise versus the enriched group; noting a five-fold difference between the standard control and exercise, a twenty seven-fold difference between the standard control versus enriched and a twenty one-fold difference between 6 the exercise and complex enriched group. The volumetric analysis showed a 15-fold difference between the standard control and exercise groups, a five-fold difference between the exercise and complex enriched and a nineteen-fold difference between the standard control and complex enriched groups. However, no statistical significant difference was found in the volumetric analysis of the dentate gyrus between the groups. / MT2017