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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Too Many Choices Confuse Patients With Dementia

Hamdy, Ronald C., Lewis, J. V., Kinser, Amber, Depelteau, Audrey, Copeland, Rebecca, Kendall-Wilson, Tracey, Whalen, Kathleen 01 January 2017 (has links)
Choices are often difficult to make by patients with Alzheimer Dementia. They often become acutely confused when faced with too many options because they are not able to retain in their working memory enough information about the various individual choices available. In this case study, we describe how an essentially simple benign task (choosing a dress to wear) can rapidly escalate and result in a catastrophic outcome. We examine what went wrong in the patient/caregiver interaction and how that potentially catastrophic situation could have been avoided or defused.
12

The Relationship Between Religious Practices and Delusional Content of Christians with Schizophrenia

Williams, Latasha Michelle 01 January 2018 (has links)
Religious beliefs and practices are an important source of symptom relief for individuals with schizophrenia; however, it can also be a debilitating source of symptom exacerbation. This quantitative study examined the cognitions and religious life orientations of Christian individuals both with and without a diagnosis of schizophrenia, as measured by the Rust Inventory of Schizotypal Cognitions (RISC) and the Religious Life Inventory (RLI) to examine a baseline for healthy religious cognitions. The aberrant-salience and attribution theories were used to explore the relationship between psychotic stimuli and religious attributions. One hundred and thirty Christian individuals from an outpatient mental health facility, both with and without a diagnosis of schizophrenia completed the RISC and the RLI. A t-test showed that individuals with schizophrenia scored higher on average on the schizotypal cognitions continuum than individuals without a diagnosis. The results of an ANOVA indicated that individuals with a Quest religious life orientation rendered higher scores on the schizotypal cognitions scale. This research study showed that higher levels of schizotypal cognitions were associated with low religiosity. Overall, individuals with schizophrenia showed no difference in religiosity compared to individuals without schizophrenia. This study addressed the stigma of religious practice among individuals with schizophrenia. Results of this study have positive social implications for individuals with schizophrenia and their practitioners/clergy who incorporate religion as a coping method for symptom relief.
13

Cyclin A and cyclin E as prognostic factors in early breast cancer

Ahlin, Cecilia January 2008 (has links)
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. 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. 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. 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. 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%. Neither cyclin E nor aberrant cyclin E was a prognostic factor in low-risk node negative breast cancer patients. 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).
14

Understanding the Mechanism of Aberrant FLVCR1 Splicing and Disrupted erythropoiesis in Diamond-Blackfan Anemia

Aidoo, Francisca Ama 24 July 2012 (has links)
Diamond Blackfan Anemia (DBA) is a congenital disorder characterized by a specific reduction in erythroid progenitor cells. Approximately 55% of patients have heterozygous mutations in ribosomal protein with 25% of these mutations in RPS19. However, it is unclear how a defect in ribosomal proteins specifically disrupts erythroid development. FLVCR1, a heme exporter, has been implicated as a potential DBA factor. FLVCR1 is essential for erythropoiesis as its disruption leads to apoptosis and disrupted erythroid differentiation. Though no FLVCR1 mutations have been found in DBA patients, our lab has shown that it is aberrantly spliced in DBA erythroid cells. Using RPS19 reduced K562 erythroid cells, I found that disruption of RPS19 leads to aberrant FLVCR1 splicing, disrupted erythropoiesis and reduced Tra2-β, ASF2 and SRp30c protein expression. This was specific to DBA as I did not find these features in a cell culture model of Shwachmann Diamond Syndrome, another ribosomal disorder.
15

Understanding the Mechanism of Aberrant FLVCR1 Splicing and Disrupted erythropoiesis in Diamond-Blackfan Anemia

Aidoo, Francisca Ama 24 July 2012 (has links)
Diamond Blackfan Anemia (DBA) is a congenital disorder characterized by a specific reduction in erythroid progenitor cells. Approximately 55% of patients have heterozygous mutations in ribosomal protein with 25% of these mutations in RPS19. However, it is unclear how a defect in ribosomal proteins specifically disrupts erythroid development. FLVCR1, a heme exporter, has been implicated as a potential DBA factor. FLVCR1 is essential for erythropoiesis as its disruption leads to apoptosis and disrupted erythroid differentiation. Though no FLVCR1 mutations have been found in DBA patients, our lab has shown that it is aberrantly spliced in DBA erythroid cells. Using RPS19 reduced K562 erythroid cells, I found that disruption of RPS19 leads to aberrant FLVCR1 splicing, disrupted erythropoiesis and reduced Tra2-β, ASF2 and SRp30c protein expression. This was specific to DBA as I did not find these features in a cell culture model of Shwachmann Diamond Syndrome, another ribosomal disorder.
16

Perception de la douleur dans la schizophrénie : mécanismes excitateurs de la douleur / Pain perception in schizophrenia: pain excitatory mechanisms

Lévesque, Mylène January 2012 (has links)
Résumé : Depuis la caractérisation de la schizophrénie, les cliniciens ont noté une sensibilité anormale à la douleur chez leurs patients. D’un autre côté, la littérature publiée sur le sujet est plutôt inconsistante concernant la nature du changement de douleur rapportée. Dans un effort pour mieux caractériser le profil de réponse à la douleur dans la schizophrénie, nous avons donné des stimulations nociceptives aiguës et prolongées (à répétition rapide; sommation temporelle) à des patients souffrant de schizophrénie et à des sujets sains. En mesurant le score de douleur subjective et la réponse du réflexe de flexion nociceptif en réponse à des stimulations électriques transcutanées, il a été possible d’évaluer la contribution des circuits spinaux à la douleur chez les patients et les sujets sains. Les résultats révèlent une sensibilité augmentée à la douleur aiguë chez les patients atteints de schizophrénie (i.e., un seuil de détection de la douleur plus bas que les sujets sains) mais aussi une diminution de la sommation temporelle de la douleur quand les stimuli se répètent fréquemment. Les différences intergroupes dans l’expérience subjective à la douleur n’étaient pas accompagnées d’une différence dans l’amplitude du réflexe nociceptif, suggérant ainsi une origine supra-spinale du phénomène observé. Il est intéressant de noter que les symptômes positifs de la schizophrénie étaient corrélés négativement avec les scores de seuil de douleur chez les patients atteints de schizophrénie, suggérant que les distorsions de la pensée et des fonctions peuvent être reliées à une augmentation de la sensibilité à la douleur aiguë dans la schizophrénie. Ces résultats suggèrent la présence d’un profil de sensibilité à la douleur unique chez les patients atteints de schizophrénie ayant des répercussions importantes pour les pratiques cliniques. // Abstract : Ever since the characterization of schizophrenia, clinicians have noted abnormal pain sensitivity in their patients. The published literature, however, is inconsistent concerning the nature of the change reported. In an effort to better characterize the pain response profile of schizophrenia patients, we provided both acute and prolonged (i.e., rapidly-repeating: temporal summation) painful stimuli to schizophrenia patients and healthy controls. By measuring subjective pain ratings and nociceptive flexion reflexes in response to transcutaneous electrical stimulations of the sural nerve, it was possible to evaluate the contribution of spinal circuits to pain in patients and controls. Results revealed increased sensitivity to acute pain in schizophrenia patients (i.e., lower pain detection thresholds for schizophrenia patients than for controls), but decreased temporal summation of pain when painful stimuli repeated frquently. Group differences in subjective experience were not accompanied by group differences in nociceptive flexion reflex activity, suggesting supra-spinal origins to the change in pain experienced by patients. Interestingly, positive symptoms correlated negatively with pain threshold values among patients, suggesting that distortions of thought and function relate to pain sensitivity in schizophrenia. These results indicate the presence of a unique pain response profile for schizophrenia patients which have important implications for clinical practice.
17

Estrogen Receptor Beta and p53 Play Integral Roles in Estradiol Mediated Protection against Colon Tumor Development

Weige, Charles 2012 August 1900 (has links)
Hormone replacement therapy and estrogen replacement therapy have shown the ability to reduce risk of colon cancer development in clinical and animal studies, but in vitro research has been unable to reproduce an estradiol (E2) induced response in colon cancer cell lines. We demonstrated that young adult mouse colonocytes (YAMC, non-malignant colonocytes) exhibit an anti-proliferative response to E2 treatment. These cells demonstrate reduced cell culture growth and increased apoptosis in response to E2. YAMC cells containing an activated Ras mutation are considered to be malignantly transformed, and lose the ability to respond to E2 treatment. Fulvestrant (ICI) was used as an estrogen receptor antagonist to determine that these results were estrogen receptor mediated. Furthermore, this effect was demonstrated to require the presence of ER? through the use of a transgenic ERbeta knockout mouse. In these mice, the presence of E2 significantly reduced the formation of azoxymethane induced premalignant lesions. Since YAMC cells exhibit an anti-proliferative response to E2 treatment, we utilized isogenic YAMC cell lines with and without a dominant negative p53 mutation to demonstrate that this E2 induced action involves p53 activity. E2 treatment results in increased p53 transcriptional activity and a pro-apoptotic change in expression of p53 downstream targets. Presence of the dominant negative p53 mutant nullifies these effects of E2 treatment. The involvement of p53 in the previously described protection against AOM induced premalignant lesions, was investigated using wild type and heterozygous p53 knockout (Het p53KO) mice. The reduction in p53 protein corresponded to reduced effectiveness of E2 treatment on the prevention of premalignant lesion formation in Het p53KO mice. In summary, our data indicate that E2 treatment induces anti-proliferative responses in non-malignant colonocytes and protects against the formation of carcinogen-induced premalignant lesions. These effects require the presence of functional ER? and p53. Further studies are required to more thoroughly elucidate the specific interactions and downstream effects of ER? and p53 in response to E2 stimulation.
18

Efeito da dieta hipercalÃrica e hiperlipÃdica na formaÃÃo de criptas aberrantes induzidas por azoximetano em mucosa cÃlica de ratos / Effect of a hypercaloric and hyperlipidic diet, rich in polyunsaturated fat, ω-3 and ω-9, aberrant crypt on formation in colonic mucosa, azoxymethane-induced in rats

IdÃlia Maria Brasil Burlamaqui 28 November 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / O cÃncer colorretal (CCR) à a quinta neoplasia mais incidente no Brasil e sua freqÃÃncia vem aumentando em paÃses industrializados. A lesÃo prÃ-neoplÃsica mais precoce com presenÃa de displasia à o foco de cripta aberrante (FCA), estando relacionada como lesÃo precursora de adenomas colorretais e cÃncer em humanos. O entendimento destas lesÃes à fundamental para esclarecer os mecanismos da carcinogÃnese colorretal e sua prevenÃÃo. O objetivo foi verificar se a dieta hipercalÃrica (DH), hiperlÃpidica, interfere na formaÃÃo de criptas aberrantes na mucosa cÃlica induzida por azoximetano (AOM), em ratos. Foram usados 36 ratos Wistar, machos, com peso mÃdio inicial de 180g a 250g e 8 semanas de idade. Foram distribuÃdos em 04 grupos com 09 animais cada: GI- Grupo com ratos submetidos à DH e nÃo expostos ao AOM, GII- Grupo com ratos submetidos à dieta padrÃo (DP) e nÃo expostos ao AOM, GIII- Grupo com ratos submetidos à DH e expostos ao AOM, GIV- Grupo com ratos submetidos à DP e expostos ao AOM. Utilizou-se, a partir da 8 semana, nos grupos I e III uma dieta hipercalÃrica (4.250cal/kg), rica em gordura poliinsaturada, relaÃÃo &#969;-6: &#969;-3 = 3:1, acrescida de fibras, minerais e vitaminas. Os grupos II e IV receberam uma dieta padrÃo (3.000cal/kg). Na 16 semana, GIII e GIV receberam injeÃÃo de AOM 15mg/kg, intraperitoneal (IP), 01 vez por semana, por 02 semanas, enquanto GI e GII receberam soluÃÃo salina a 0,9%. Foram mortos na 15 semana apÃs a induÃÃo com carcinÃgeno ou administraÃÃo IP de soluÃÃo estÃril. Avaliaram-se os animais quanto ao peso, alteraÃÃo clÃnica, presenÃa de adenomas, FCA e o nÃmero de criptas por foco (multiplicidade) de acordo com a localizaÃÃo cÃlica (proximal, medial e distal). Os resultados foram submetidos aos testes de anÃlise de variÃncia e estabelecido o nÃvel de 5% (p < 0,05) para a rejeiÃÃo da hipÃtese de nulidade. Verificou-se que a dieta hipercalÃrica hiperlÃpidica promoveu um incremento no peso no grupo III, quando comparado ao grupo IV e nÃo apresentou aumento significante no nÃmero total de FCA nos segmentos mÃdio (p = 0,985) e distal (p = 0,854). Analisando ambos os grupos em relaÃÃo à multiplicidade de FCA, nÃo houve predominÃncia da presenÃa de 01 a 04 criptas nos segmentos mÃdio (p = 0,499) e distal (p = 0,244), como tambÃm, de 05 ou mais criptas nos segmentos mÃdio (p = 0,371) e distal (p = 0,820). Verificando a presenÃa do nÃmero total de criptas por foco em toda a mucosa cÃlica, o teste do qui-quadrado mostrou que o grupo IV apresenta, em proporÃÃo, um maior nÃmero de focos com 05 ou mais criptas do que o grupo III (P= 0,043). Conclui-se que a dieta usada aumenta o peso corporal, porÃm nÃo interfere na quantidade de FCA, contudo reduz o aparecimento de criptas aberrantes, quando &#8805; 5 criptas por foco, no colo de ratos Wistar, induzido por azoximetano. / Colorectal cancer is the fifth most common type of cancer in Brazil and the incidence is growing in developed countries. The earliest preneoplastic lesion presenting dysplasia is aberrant crypt foci (ACF), a precursor of colorectal adenoma and cancer in humans. Knowledge of ACF formation is crucial to understanding the mechanisms involved in colorectal cancer and their inhibition. The objective of this study was to determine whether a hypercaloric, hyperlipidic diet (HCD) affects azoxymethane (AOM)-induced ACF formation in rat colonic mucosa. Thirty-six 8-week old male Wistar rats weighing 180-250g were distributed into 4 groups of 9 animals each: Group I: HCD without AOM; Group II: normocaloric diet (NCD) without AOM; Group III: HCD and AOM; Group IV: NCD and AOM. From the eighth week onwards the animals in Groups I and III were fed HCD (4,250 cal/kg; rich in polyunsaturated fat; ratio &#969;6:&#969;3=3:1, with addition of fiber, minerals and vitamins). The animals in Groups II and IV were fed NCD (3,000 cal/kg). At 16 weeks, the animals in Groups III and IV were injected i.p. with 15 mg/kg AOM once a week for 2 weeks, while the animals in Groups I and II received 0.9% physiological saline. At 15 weeks after AOM or saline administration, the animals were euthanized and their weight, clinical changes, adenomas, ACF and number of crypts per focus (multiplicity) according to colon section (proximal, middle or distal) were registered. The findings were submitted to variance analysis and the level of statistical significance was set at 5% (p<0.05). HCD was found to promote weight increase in Group III compared to Group IV. No significant increase in the total number of ACF was observed for the middle and distal segments (p=0.985 and p=0.854, respectively). The multiplicity of foci with 1-4 aberrant crypts was similar for the middle and distal segments (p=0.499 and p=0.244, respectively). The corresponding figures for foci with &#8805;5 aberrant crypts were p=0.371 and p=0.820. The total number of ACF in the colonic mucosa differed significantly between Group IV and Group III (&#967;2 = 4.091; p=0.043). It may thus be concluded that HCD promotes weight increase and, while not affecting the total number of ACF, reduces the proportion of foci with &#8805;5 aberrant crypts, thereby indirectly preventing the emergence of preneoplastic lesions in rat colonic mucosa.
19

The neural basis of aberrant salience attribution in unmedicated patients with schizophrenia spectrum disorders

Delfin, Carl January 2014 (has links)
Due to abnormal functioning of the brain’s reward and prediction system patients with schizophrenia spectrum disorders are thought to assign salience to non-relevant objects and events and to form context-inappropriate associations. The brain’s ventral striatum is critical in the formation of associations, and aberrant associations are believed to create delusional content during psychosis. The study wanted to examine the neural response, particularly in the ventral striatum, combined with subjective reports as patients learn associations in an aversive Pavlovian conditioning paradigm. The stimuli were randomized and involved circles of different colors. The conditioned stimuli (CS+) was followed by an unconditioned stimuli (US), consisting of an unpleasant sound, in 50% of events. The unconditioned (CS-) stimuli was followed by a low, not unpleasant sound in 50% of events. The degree of striatal activation was thought to be associated with the severity of patient’s illness. Functional magnetic resonance imaging (fMRI) blood-oxygen-level dependent (BOLD) responses were examined in eleven unmedicated non-institutionalized patients with schizophrenia spectrum disorders and 15 matched healthy controls. No significant within group differences in neural or subjective response to the [CS+ &gt; CS-] contrast were found. No significant associations between severity of illness and degree of striatal activation in response to CS+ or CS- were found. Significant differences in neural activation for the [CS+ &gt; CS-] contrast were found in the ventral striatum, the right inferor frontal gyrus, and the right angular gyrus, with patients exhibiting stronger activation compared to controls. The results and implications are discussed along with suggestions for future research.
20

Integrating regulatory and methylome data for the discovery of clear cell Renal Cell Carcinoma (ccRCC) variants

Calvert-Joshua, Tracey January 2015 (has links)
>Magister Scientiae - MSc / Kidney cancers, of which clear cell renal cell carcinoma comprises an estimated 70%, have been placed amongst the top ten most common cancers in both males and females. With a mortality rate that exceeds 40%, kidney cancer is considered the most lethal cancer of the genitourinary system. Despite advances in its treatment, the mortality- and incidence rates across all stages of the disease have continued to climb. Since the release of the Human Genome Project in the early 2000’s, most genetics studies have focused on the protein coding region of the human genome, which accounts for a mere 2% of the entire genome. It has been suggested that diverting our focus to the other 98% of the genome, which was previously dismissed as non-functional “junk DNA”, could possibly contribute significantly to our understanding of the underlying mechanisms of complex diseases.In this study a whole genome sequencing somatic mutation data set from the International Cancer Genome Consortium was used. The non-coding somatic mutations within the promoter, intronic, 5-prime untranslated and 3-prime untranslated regions of clear cell renal cell carcinoma-implicated genes were extracted and submitted to RegulomDB for their functional annotation.As expected, most of the variants were located within the intronic regions and only a small subset of identified variants was predicted to be deleterious. Although the variants all belonged to a selected subset of kidney cancer-associated genes, the genes frequently mutated in the non-coding regions were not the same genes that were frequently mutated in the whole exome studies (where the focus is on the coding sequences). This indicates that with whole genome sequencing studies a new set of genes/variants previously unassociated with the clear cell renal cell carcinoma could be identified. In addition, most of the non-coding somatic variants fell within multiple transcriptions factor binding sites. Since many of these variants were also deleterious (as predicted by RegulomDB), this suggests that mutations in the non-coding regions could contribute to disease due to their role in transcription factor binding site disruptions and their subsequent impact on transcriptional regulation. The substantial overlap between the genes with the most aberrantly methylated variants and the genes with the most transcription factor binding site disruptions signifies a potential link between differential methylation and transcription factor binding site affinities. In contrast to the upregulated DNA methylation generally seen in promoter methylation studies, all of the significant hits in this study were hypomethylated, with the subsequent up-regulation of the genes of interest, suggesting that in the clear cell renal cell carcinoma, aberrant methylation may play a role in activating proto-oncogenes, rather than the silencing of genes. When a cross-analysis was carried out between the gene expression patterns and the transcription factor binding site disruptions, the non-coding somatic variants and differential methylation profiles, the genes affected again showed a clear overlap. Interestingly, most of the variants were not present in the 1000genomes data and thus represent novel mutations, which possibly occurred as a result of genomic instability. However, identifying novel variants are always promising, since they epitomise the possibility of developing pioneering ways to target diseases. The numerous detrimental effects a single non-coding mutation can have on other genomic processes have been demonstrated in this study and therefore validate the inclusion of non-coding regions of the genome in genetic studies in order to study complex multifactorial diseases. / National Research Foundation (NRF) and DAAD

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