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In culture, exposure to penicillin and other stressors induce chlamydiae to enter a non-infectious but viable state termed persistence. Chlamydiae may reenter their normal developmental cycle after stressor removal. Though aberrant RB similar to those present in culture models of persistence have been observed within infected tissues, the existence of persistent chlamydiae has not been definitively demonstrated in vivo. As a result, the role of persistent organisms in pathogenesis is undefined. In order to establish an experimentally tractable model of in vivo persistence, Chlamydia muridarum vaginally-infected mice were gavaged with either water or amoxicillin (amox). Vaginal swabs were collected for chlamydial titration and RNA isolated for quantification of pre-16s rRNA. Uterine tissue was analyzed by transmission electron microscopy (TEM). Although amox-treatment reduced vaginal shedding by >99%, C. muridarum pre-16s rRNA accumulation was unchanged by treatment. These data indicate that the amox-exposed organisms were viable but not infectious. Furthermore, TEM analyses demonstrated that inclusions in amox-treated animals contained primarily large, aberrant RB, but those observed in untreated control animals were normal. Collectively, these data suggest that amoxicillin treatment induces C. muridarum to enter the persistent state in vivo. This model also represents the first experimentally tractable animal model of chlamydial persistence.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Repetitive questioning is due to an impaired episodic memory and is a frequent, often presenting, problem in patients with Alzheimer’s disease (amnestic type). It is due to the patients’ difficulties learning new information, retaining it, and recalling it, and is often aggravated by a poor attention span and easy distractibility. A number of factors may trigger and maintain repetitive questioning. Caregivers should try to identify and address these triggers. In the case discussion presented, it is due to the patient’s concerns about her and her family’s safety triggered by watching a particularly violent movie aired on TV. What went wrong in the patient/caregiver interaction and how it could have been avoided or averted are explored. Also reviewed are the impact of repetitive questioning, the challenges it raises for caregivers, and some effective intervention strategies that may be useful to diffuse the angst that caregivers experience with repetitive questioning.

The purpose of this study was to answer questions about affect intensity and self-perceived arousal differences in aberrant self-promoters (ASPs) and in individuals high and low in affect intensity (AI). Participants in the study completed a task asking them to respond as quickly and accurately as possible to letter strings presented for 200ms on a computer screen. They completed the task once with letter strings that formed words with an emotional valance and a second time with neutral-valence words. After each task, participants made self-reports of Energy and Tense dimensions of arousal as measured by the Activation-Deactivation Adjective Checklist. As first formulated, the study examined 4 groups of n̲ = 30 (ASPs, non-ASP controls, high-AIs, and low-AIs). Results showed that, as hypothesized, ASPs scored significantly lower than high-AIs on the Affect Intensity Measure (AIM). Other hypotheses were not supported by analyses of the original four groups. However, because about 1/3 of the ASPs exhibited high AIM scores, ASPs were divided into primary and secondary types: (a) those who scored low and (b) those who scored high on the AIM. Subsequent post hoc analyses, based on the hypotheses that had not been supported initially, were conducted on five groups of n̲ = 7. The study found that low-AI ASPs reported significantly lower arousability levels than high-AIs. Results also showed that controls, high-AIs, and low-AIs all reacted significantly more slowly to emotional words than to neutral words. Low-AI ASPs failed to demonstrate this response-time slowing, indicating that, like psychopaths, ASPs may process positive, negative, and neutral stimuli similarly. Additional results indicated that low-AI ASPs decreased both energetic and tension arousal levels after the emotional word task, compared to the neutral word task, whereas high-AIs reported corresponding increases in these types of arousal. These findings support Larsen and Diener's (1987) theory regarding arousal differences in high- and low-AIs. Implications of these findings are discussed in terms of a weak Behavioral Inhibition System (Gray, 1987). / Ph. D.

A sample of aberrant self-promoters (ASPs) was identified through their pattern of answers on a 179-item questionnaire. A group of comparison participants who did not exhibit the ASP pattern was also identified. The participants viewed a videotape of a lecture and rated the lecturer's performance. Half of the participants were told that they were required to provide face-to-face feedback to the lecturer (the accountability condition); the other half were not given these instructions (non-accountability condition). Also, half of the participants were told that there may be an opportunity for them to appear on a training video for graduate student instructors (opportunity for personal recognition condition); the other half were not told of this opportunity (no opportunity condition). This study attempted to identify the roles of aberrant self-promotion, accountability, and opportunity for personal recognition in rater accuracy and rater leniency. / Master of Science

<p>Breast cancer is one of the most common malignancies in women. Due to early detection and the use of screening programs approximately 60% of all new cases lack lymph node involvement. Today, a substantial proportion of these women will be offered adjuvant systemic chemotherapy. However, better proliferation markers are needed to predict patient outcome and to avoid overtreatment. </p><p>Cyclin A, cyclin E and Ki-67 are all markers for proliferation and involved in the regulation of the cell cycle. Overexpression has been associated with disease recurrence in several studies, but the results have not been consistent. However, none of these studies has investigated aberrant expression of cyclin E (the expression of cyclin E during phases of the cell cycle other than late G1 and early S-phase). Studies have shown that aberrant cyclin E might provide additional prognostic information compared to cyclin E alone.</p><p>The aims of this thesis were 1.to investigate the prognostic value of cyclin A, cyclin E and aberrant cyclin E in early breast cancer. 2.to validate the tissue microarray (TMA) technique for cyclin A and 3.to define the most optimal cut-off values for cyclin A and Ki-67.</p><p>We found that the agreement of TMA and large section results was good with kappa values 0.62-0.75 and that the reproducibility of the two readers’ results was good or even very good, with kappa values 0.71 – 0.87. </p><p>The optimal cut-off value for cyclin A average was 8% and for cyclin A maximum value 11%. The corresponding values for Ki-67 were 15 and 22%. </p><p>Neither cyclin E nor aberrant cyclin E was a prognostic factor in low-risk node negative breast cancer patients. </p><p>Finally, we conclude that cyclin A is a prognostic factor in node negative breast cancer (univariate analysis average value OR=2.9 95% CI 1.8-4.6; maximum value OR=3.7 95% CI 2.3-5.9).</p>

This dissertation has explored the origins of the field of Behavioral Disorders via a qualitative approach. In order to collect data, interviews were conducted with respondents who were selected via purposeful sampling. All respondents have had a significant impact on the field of special education as evidenced by scholarship and leadership throughout their careers. Data analysis of the interview transcriptions was accomplished through the utilization of computer software. The data indicated six areas/topics that were seen among respondents as being significant to the development of the field of Behavioral Disorders.

O Orlistat é um membro de uma classe de drogas usadas como tratamento para obesidade. No entanto, a segurança de seu uso em longo prazo ainda não é conhecida. O Orlistat exerce sua atividade no lúmen do trato gastrintestinal inibindo a enzima lipase pancreática, responsável pela hidrólise dos triacilglicerídeos normalmente ingeridos com a dieta. Esse medicamento, quimicamente sintetizado, é um derivado da lipstatina, inibidora natural da lipase produzida pelo Streptomyces toxytricini. Assim, a excreção de gordura fecal fica significativamente aumentada com o uso do Orlistat. Estudos epidemiológicos e em modelos experimentais, sugerem que o aumento das dietas hipergordurosas tem efeito promotor para o câncer colorretal. Tal efeito deve ser relacionado, pelo menos parcialmente, às mudanças intra-colônicas causadas pela ação direta da gordura nas células da mucosa do cólon, os colonócitos. O estudo atual tem como objetivo verificar os efeitos do Orlistat na formação colônica de focos de criptas aberrantes (FCA) e na proliferação celular epitelial da mucosa gastrintestinal. Ratos Wistar machos receberam dieta padrão ou dieta com aumento de gordura, suplementada ou não com Orlistat (200 mg/kg), e duas doses semanais do carcinógeno químico Dimetilhidrazina (DMH) (25 mg/kg). Após 30 dias, nos animais tratados com DMH, o Orlistat foi associado a um aumento significativo no número de FCAs colônicos e na proliferação celular epitelial da mucosa do cólon, independentemente da dieta. Os achados obtidos neste trabalho permitem concluir que o aumento do teor de gordura na luz do cólon distal, em decorrência da ação do Orlistat, pode potencializar a ação da DMH na formação de FCAs e no aumento da proliferação celular epitelial da mucosa colônica. / Orlistat is a member of a drug class used as obesity treatment. However, the security of its use in a long period of time is not known yet. Orlistat has its activity in the lumen of the gastrointestinal tract inhibiting the pancreatic lipase enzyme responsible for the hydrolyze of the triglycerides that usually are swallowed with the diet. This drug chemically synthesized, is a derived from lipstatina, that inhibit naturally the lipase produced by Streptomyces Toxytricini. So, the excretion of fat excrement stays significantly increased with the use of Orlistat. Epidemiologic studies and in experimental pattern, suggest that the increase of the high-fat diets facilitate the appearance of the colorectal cancer. Such effect must be related, at least partially to the changes intracolonic caused by the direct action of the fat in the cells of the colon mucous, the colonocytes. The current study has as objective to check the effects of the Orlistat on the formation of rat colonic aberrant crypt foci (ACF) and in the epithelial cell proliferation of the gastrointestinal mucous. Male Wistar rats received either a standard diet or a high fat diet (HFD), supplemented or not with Orlistat (200 mg/kg chow) and two doses of the carcinogen dimethyl-hydrazine (25 mg/Kg). After 30 days, Orlistat was associated to a significant increase in the number of colonic ACFs and cell proliferation in DMH-treated animals, independently of the HFD. The find got in this study permit to conclude that the increase in the level of adiposity inside the distal colon, due to Orlistat action, can potencializar the DMH action in the formation of ACFs and in the increase of epithelial cell proliferation of the colônica mucous.

O Orlistat é um membro de uma classe de drogas usadas como tratamento para obesidade. No entanto, a segurança de seu uso em longo prazo ainda não é conhecida. O Orlistat exerce sua atividade no lúmen do trato gastrintestinal inibindo a enzima lipase pancreática, responsável pela hidrólise dos triacilglicerídeos normalmente ingeridos com a dieta. Esse medicamento, quimicamente sintetizado, é um derivado da lipstatina, inibidora natural da lipase produzida pelo Streptomyces toxytricini. Assim, a excreção de gordura fecal fica significativamente aumentada com o uso do Orlistat. Estudos epidemiológicos e em modelos experimentais, sugerem que o aumento das dietas hipergordurosas tem efeito promotor para o câncer colorretal. Tal efeito deve ser relacionado, pelo menos parcialmente, às mudanças intra-colônicas causadas pela ação direta da gordura nas células da mucosa do cólon, os colonócitos. O estudo atual tem como objetivo verificar os efeitos do Orlistat na formação colônica de focos de criptas aberrantes (FCA) e na proliferação celular epitelial da mucosa gastrintestinal. Ratos Wistar machos receberam dieta padrão ou dieta com aumento de gordura, suplementada ou não com Orlistat (200 mg/kg), e duas doses semanais do carcinógeno químico Dimetilhidrazina (DMH) (25 mg/kg). Após 30 dias, nos animais tratados com DMH, o Orlistat foi associado a um aumento significativo no número de FCAs colônicos e na proliferação celular epitelial da mucosa do cólon, independentemente da dieta. Os achados obtidos neste trabalho permitem concluir que o aumento do teor de gordura na luz do cólon distal, em decorrência da ação do Orlistat, pode potencializar a ação da DMH na formação de FCAs e no aumento da proliferação celular epitelial da mucosa colônica. / Orlistat is a member of a drug class used as obesity treatment. However, the security of its use in a long period of time is not known yet. Orlistat has its activity in the lumen of the gastrointestinal tract inhibiting the pancreatic lipase enzyme responsible for the hydrolyze of the triglycerides that usually are swallowed with the diet. This drug chemically synthesized, is a derived from lipstatina, that inhibit naturally the lipase produced by Streptomyces Toxytricini. So, the excretion of fat excrement stays significantly increased with the use of Orlistat. Epidemiologic studies and in experimental pattern, suggest that the increase of the high-fat diets facilitate the appearance of the colorectal cancer. Such effect must be related, at least partially to the changes intracolonic caused by the direct action of the fat in the cells of the colon mucous, the colonocytes. The current study has as objective to check the effects of the Orlistat on the formation of rat colonic aberrant crypt foci (ACF) and in the epithelial cell proliferation of the gastrointestinal mucous. Male Wistar rats received either a standard diet or a high fat diet (HFD), supplemented or not with Orlistat (200 mg/kg chow) and two doses of the carcinogen dimethyl-hydrazine (25 mg/Kg). After 30 days, Orlistat was associated to a significant increase in the number of colonic ACFs and cell proliferation in DMH-treated animals, independently of the HFD. The find got in this study permit to conclude that the increase in the level of adiposity inside the distal colon, due to Orlistat action, can potencializar the DMH action in the formation of ACFs and in the increase of epithelial cell proliferation of the colônica mucous.