Background: Coinfections with multiple types of human papillomavirus (HPV) are a common occurrence among HPV-infected individuals, but the clinical significance and etiology of these infections remain unclear. Though current evidence suggests that women with coinfections have increased HPV exposure (i.e. more sexual partners), it is also hypothesized that these women may represent a subgroup with increased HPV susceptibility, though this has been rarely studied to date. Purpose: The purpose of this project was to examine the occurrence, determinants and dynamics of HPV coinfections in a cohort of university students in order to explore the relationship(s) between coinfections, lifestyle factors and immunological susceptibility. Methods: This project is based on a secondary analysis of data from the McGill-Concordia Cohort, a longitudinal study of the natural history of HPV infection in 621 female university students in Montreal, Quebec. Participants were followed for 2 years at 6-month intervals. At each visit, cervical specimens were collected for cytology and HPV testing, and women completed a questionnaire about lifestyle and risk behaviours. Two definitions of coinfections were used: cumulative coinfection over follow-up and concurrent coinfection at each visit. Kaplan-Meier techniques were used to estimate incidence and duration of coinfections and multiple logistic regression was used to identify determinants of coinfections and associations between coinfections and squamous intraepithelial lesions (SIL). Results: More than half of the cohort became infected with HPV and of those, over 60% acquired multiple HPV types over follow-up. Incidence of coinfections was significantly increased among HPV-infected women at enrollment. The most important determinant of coinfection occurrence was number of sexual partners (both lifetime and new), though some genes of the immune response (HLA-DQB1*06:02, HLA-G*01:01:03 and HLA-G*01:01:05) were also significant predictors. Women with coinfections, particularly those with 4+ HPV types, also had longer infection durations and greatly increased odds of SIL. Conclusions: Women with coinfections acquire new HPV types at an increased rate and have greater HPV persistence and occurrence of SIL, which may indicate immunological susceptibility. HPV coinfections mainly occur due to increased sexual activity but a decreased immune response to the virus may also be involved in a subset of women. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2011-04-21 01:04:26.265

Entre un 25 y un 50% de los pacientes que sufren un infarto cerebral pueden desarrollar alteraciones cognitivas y una demencia en los tres meses posteriores. Las tecnologías del diagnóstico por imagen (TAC RM), han constituido un avance importante en la mejora del diagnóstico en los diferentes procesos patológicos. La presente tesis doctoral tiene como objetivo identificar las alteraciones neuropsicológicas, afectivas y cognitivo-conductuales que aparecen después de una lesión vascular cerebral, así como su evolución a los tres meses, en sujetos que no manifiestan lesiones corticales en la fase aguda del ictus.La muestra está compuesta por 74 pacientes con un ictus no cortical. También se analizan las correlaciones entre el volumen de la lesión (resonancia magnética, secuencias de DRM y FLAIR) y las puntuaciones en los test cognitivos, afectivos y un inventario cognitivo-conductual.RESULTADO: se lleva a cabo un análisis factorial exploratorio de componentes principales. Con un KMO de .782, se extraen siete componentes que explican un porcentaje acumulado de 72,54 de la varianza. Entre la evaluación en la fase aguda y la realizada tres meses después, no se observa una significativa mejoría en la memoria de aprendizaje y en la memoria diferida, aunque sí se verifica un mejoría en las otras pruebas cognitivas (función ejecutiva, denominación, atención, función visuoespacial y función psicomotora). Se observan puntuaciones estadísticamente significativas en los test cognitivos, afectivos y cognitivo-conductual cuando se comparan los pacientes con ictus recurrentes y no recurrentes, entre los diferentes grupos de edad y nivel educativo. En el inventario de obsesiones-compulsiones de Maudsley, se seleccionan dos grupos según sus puntuaciones (mayor o igual a 12) o (menor o igual a 13): los pacientes con puntuaciones menor o igual a 13 obtienen un significativo menor rendimiento en los siguientes test: examen cognitivo general (MMSE) p = ,001; escala de depresión (HRS-D) p: ,028; Dígitos WAIS p = ,037; memoria de aprendizaje (RAVLT) p: ,001; fluencia fonética p = ,002; fluencia semántica p = ,030; TMT (A y B) p = ,060; y p = ,010 respectivamente; test de procesos de denominación por confrontación visual (BNT) p = , 060; alternancias motoras (AM) p = ,015. En la Escala de Depresión de Hamilton, se seleccionan dos grupos según las puntuaciones en dicho test (6 y 7). Los pacientes con puntuaciones 7 obtienen un rendimiento significativamente menor en los test de cognición general (MMSE) p = ,004; Dígitos WAIS p =, 001; memoria de aprendizaje (RAVLT) p = ,001; fluencia fonética (FF) p = ,041; TMT-A p = ,013; test de denominación (BNT) p = , 022; funciones visuoespaciales (OLB) p = ,020; alternancias motoras (AM) p = , 031; y test de Cartas de Wisconsin (categorías) p = , 011.En el segundo estudio, se observan correlaciones estadísticamente significativas entre el volumen de la lesión (secuencia de DRM y FLAIR) con la fluencia fonética procesos de denominación (BNT), Test de cartas de Wisconsin. Cuando, además, utilizamos la lateralización de la lesión, se observa un rendimiento inferior en los test de denominación, TMT-B y WISCONSIN en el hemisferio izquierdo comparados con los del hemisferio derecho.CONCLUSIONES: la variable edad, nivel educativo y sexo afectan al rendimiento en la cognición de los pacientes con ictus. Sobretodo, la variable edad es un factor de mal pronóstico en el rendimiento en algunas pruebas cognitivas. No se observan diferencias por la lateralización de la lesión en la escala de Depresión de Hamilton ni en el Inventario MOCI, ni en la escala de Manía. Cuando se comparan las puntuaciones entre la fase aguda y su evaluación posterior a los tres meses, se observa una mejoría general en los resultados de los pacientes. Aunque estos no alcanzan un rendimiento parecido o igual al de los sujetos control. Las escalas de depresión de Hamilton y el inventario cognitivo -conductual MOCI afectan al rendimiento de la cognición (memoria de aprendizaje, fluencias verbales, función psicomotora). Además, se obtienen correlaciones estadísticamente significativas entre el volumen de la lesión, medido mediante secuencias DRM y FLAIR, y las puntuaciones en el test de denominación (BNT) y el test TMT-B. / "Cognitive and affective behaviour in a group of patients with non-cortical stroke" SUMMARY:Between 25 and 59% of patients with stroke may develop cognitive and degenerative impairment within three months. Affective and behavioural alterations may affect rehabilitation and recovery. Neuroimaging diagnostic techiques (CT, MRI) have significantly improved diagnosis of different pathological procesesses. DRM sequences allow us to visualise vascular lesions and compare lesion volumes with neuopsychological test scores. This thesis attempts to identify the neuropsychological, affective and cognitive-behavioural alterations appearing after cerebrovascular lesions and follows the evolution at three months in subjects not displaying cortical lesions in acute stroke. RESULTS AND CONCLUSION:Seventy-four cerebral stroke patients with a mean age of 60.32 years (SD 13.6). 25.7% of the patients were women. 73% of strokes were ischaemic and 27% were haemorrhagic. Also, a healthy control group of 20 volunteers was recruited. Exploratory factorial analysis of the principal components was performed. The Kaiser-Mayer-Olkin measure of sampling adequacy was .782. Seven components were extracted explain an accumulated percentage of variance of 72.54.No significant differences were observed in the side of the lesion. Significant differences were found in the semantic verbal fluency cognitive variable (p=.053). Patients with haemorrhagic lesions performed worse in this variable than patients with ischaemic lesions. Although there is an improvement in learning memory and long-term memory at three months, as compared to the acute phase, levels were still below the control group. Significant differences are observed in cognitive performance with regard to age, educational level, and sex. Cut-off points were established in the Hamilton Depression Scale and the MOCI Inventory: Statistically differences were observed in cognitive performance. Also, statistically significant differences were observed between the volume lesion and the Naming Test (BNT) and the TMT-B.

Low back pain is an ailment that affects a significant portion of the community. However, due to the complexity of the spine, which is a series of interconnected joints, and the loading conditions applied to these joints the causes for back pain are not well understood. Investigations of damage or failure of the spinal structures from a mechanical viewpoint may be viewed as a way of providing valuable information for the causes of back pain. Low back pain is commonly associated with injury to, or degeneration of, the intervertebral discs and involves the presence of tears or lesions in the anular disc material. The aim of the study presented in this thesis was to investigate the biomechanical effect of anular lesions on disc function using a finite element model of the L4/5 lumbar intervertebral disc. The intervertebral disc consists of three main components - the anulus fibrosus, the nucleus pulposus and the cartilaginous endplates. The anulus fibrosus is comprised of collagen fibres embedded in a ground substance while the nucleus is a gelatinous material. The components of the intervertebral disc were represented in the model together with the longitudinal ligaments that are attached to the anterior and posterior surface of the disc. All other bony and ligamentous structures were simulated through the loading and boundary conditions. A high level of both geometric and material accuracy was required to produce a physically realistic finite element model. The geometry of the model was derived from images of cadaveric human discs and published data on the in vivo configuration of the L4/5 disc. Material properties for the components were extracted from the existing literature. The anulus ground substance was represented as a Mooney-Rivlin hyperelastic material, the nucleus pulposus was modelled as a hydrostatic fluid in the healthy disc models and the cartilaginous endplates, collagen fibres and longitudinal ligaments were represented as linear elastic materials. A preliminary model was developed to assess the accuracy of the geometry and material properties of the disc components. It was found that the material parameters defined for the anulus ground substance did not accurately describe the nonlinear shear behaviour of the tissue. Accurate representation this nonlinear behaviour was thought to be important in ensuring the deformations observed in the anulus fibrosus of the finite element model were correct. There was no information found in the literature on the mechanical properties of the anulus ground substance. Experimentation was, therefore, carried out on specimens of sheep anulus fibrosus in order to quantify the mechanical response of the ground substance. Two testing protocols were employed. The first series of tests were undertaken to provide information on the strain required to initiate permanent damage in the ground substance. The second series of tests resulted in the acquisition of data on the mechanical response of the tissue to repeated loading. The results of the experimentation carried out to determine the strain necessary to initiate permanent damage suggested that during daily loading some derangement might be caused in the anulus ground substance. The results for the mechanical response of the tissue were used to determine hyperelastic constants which were incorporated in the finite element model. A second order Polynomial and a third order Ogden strain energy equation were used to define the anulus ground substance. Both these strain energy equations incorporated the nonlinear mechanical response of the tissue during shear loading conditions. Using these geometric data and material properties a finite element model of a representative L4/5 intervertebral disc was developed. When the measured material parameters for the anulus ground substance were implemented in the finite element model, large deformations were observed in the anulus fibrosus and excessive nucleus pressures were found. This suggested that the material parameters defining the anulus ground substance were overly compliant and in turn, implied the possibility that the stiffness of the sheep anulus ground substance was lower than the stiffness of the human tissue. Even so, the mechanical properties of the sheep joints had been shown to be similar to those of the human joint and it was concluded that the results of analyses using these parameters would provide valuable qualitative information on the disc mechanics. To represent the degeneration of the anulus fibrosus, the models included simulations of anular lesions - rim, radial and circumferential lesions. Degeneration of the nucleus may be characterised by a significant reduction in the hydrostatic nucleus pressure and a loss of hydration. This was simulated by removal of the hydrostatic nucleus pressure. Analyses were carried out using rotational loading conditions that were comparable to the ranges of motion observed physiologically. The results of these analyses showed that the removal of the hydrostatic nucleus pressure from an otherwise healthy disc resulted in a significant reduction in the stiffness of the disc. This indicated that when the nucleus pulposus is extremely degenerate, it offers no resistance to the deformation of the anulus and the mechanics of the disc are significantly changed. Specifically, the resistance to rotation offered by the intervertebral disc is reduced, which may affect the stability of the joint. When anular lesions were simulated in the finite element model they caused minimal changes in the peak moments resisted by the disc under rotational loading. This suggested that the removal of the nucleus pressure had a greater effect on the mechanics of the disc than the simulation of anular lesions. The results of the finite element model reproduced trends observed in both the healthy and degenerate intervertebral disc in terms of variations in nucleus pressure with loading conditions, axial displacement of the superior surface and bulge of the peripheral anulus. It was hypothesised that the reduced rotational stiffness of the degenerate disc may result in overload of the surrounding innervated osseoligamentous anatomy which may in turn cause back pain. Similarly back pain may result from the abnormal deformation of the innervated peripheral anulus in the vicinity of anular lesions. Furthermore, it was hypothesised that biochemical changes may result in the degeneration of the nucleus, which in turn may cause excessive strains in the anulus ground substance and lead to the initiation of permanent damage in the form of anular lesions. With further refinement of the components of the model and the methods used to define the anular lesions it was considered that this model would provide a powerful analysis tool for the investigation of the mechanics of intervertebral discs with and without significant degeneration.

Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 6 uppsatser.

As lesões dermatológicas submetidas à terapia com fontes de radiação podem apresentar diferentes padrões de malignidade. Os tumores de pele mais comumente encontrados nos serviços de radioterapia são os carcinomas. A radioterapia de lesões dermatológicas é realizada com feixes de radiação de baixa penetração como os raios-X de ortovoltagem, feixes de elétrons e fontes radioativas (192Ir, 198Au, e 90Sr) arranjadas em moldes superficiais ou aplicadores metálicos. O presente trabalho teve como objetivo analisar o perfil de distribuição de dose terapêutica produzida por fontes de radiação utilizadas em procedimentos radioterápicos em lesões superficiais da pele. As medidas experimentais, para as análises dosimétricas das fontes de radiação, foram comparadas com cálculos obtidos no sistema computacional baseado no Método de Monte Carlo. Os resultados obtidos com os cálculos computacionais através do código MCNP-4C apresentaram uma boa concordância com as medidas experimentais. As comparações das medidas experimentais com os cálculos obtidos através do código MCNP-4C, foram utilizadas para validar os cálculos e assim possibilitar o uso de dados de simulação para aplicação em casos clínicos de rotina. A comparação entre diferentes modalidades podem fornecer um indicativo dos procedimentos mais adequados em cada caso clínico. / Skin lesions undergoing therapy with radiation sources may have different patterns of malignancy. Malignant lesions or cancer most commonly found in radiotherapy services are carcinomas. Radiation therapy in skin lesions is performed with low penetration beams and orthovoltage X-rays, electron beams and radioactive sources (192Ir, 198Au, e 90Sr) arranged on a surface mold or in metal applicator. This study aims to analyze the therapeutic radiation dose profile produced by radiation sources used in skin lesions radiotherapy procedures . Experimental measurements for the analysis of dosimetric radiation sources were compared with calculations obtained from a computer system based on the Monte Carlo Method. Computational results had a good agreement with the experimental measurements. Experimental measurements and computational results by the MCNP4C code were both physically consitent as expected. These experimental measurements compared with calculations using the MCNP-4C code have been used to validate the calculations obtained by MCNP code and to provide a reliable medical application for each clinical case.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As lesões impalpáveis da mama que muitas das vezes são assintomáticas, podem corresponder à um estágio de progressão de câncer difícil de ser detectado, durante os exames de rotina de palpação da mulher. O único método possível para a descoberta dessas lesões é através dos exames de imagem da mama, de modo geral, através da mamografia, que geralmente ocorre após os 45 anos. Devido a esses fatores, lesões impalpáveis, são frequentemente, descobertas apenas quando o estágio de desenvolvimento da doença já está avançado e as intervenções terapêuticas são menos reparadoras. Com a finalidade de iniciar a caracterização de tumores impalpáveis iniciais, objetivamos analisar o perfil genético (mutação) e epigenético (metilação de região promotora) de regiões do DNA relacionadas ao gene supressor tumoral TP53, provenientes de biópsias de mulheres residentes do Estado do Rio de Janeiro. Neste trabalho, foram investigadas 34 amostras de tecido de tumor de mama, por sequenciamento de DNA, nos exons de 5 a 8 do gene TP53. Nesta região, não foi encontrada nenhuma mutação. Este resultado pode estar relacionado ao tipo inicial de lesão, de acordo com os dados radiológicos das lesões de categorias 3 e 4 da escala BIRADS. Para verificar o estado de metilação da região promotora do gene TP53, analisamos 30 pares de amostras (sangue e tumor) de pacientes com suspeita de câncer de mama, pela técnica MSP-PCR. Nenhuma amostra tumoral apresentou alteração no estado de metilação na região promotora do gene TP53, quando comparada à amostra normal. Um motivo possível para a disparidade de resultados em relação à outros trabalhos pode ter sido a utilização da técnica. A caracterização das lesões impalpáveis apenas foi iniciada neste trabalho, no qual pudemos constatar que a mutação em TP53 pode ser um evento mais tardio. Portanto, a lesão mamária, em suas diferentes formas, continuará a ser o assunto investigado por nosso grupo, ampliando o número de amostras e alcançando melhor conexão da conduta e dos métodos clínicos já existentes, com as novas possibilidades de diagnóstico via marcadores moleculares em tumores e fluidos biológicos / Nonpalpable breast lesions that are often asymptomatic, may correspond to a stage of progression of the cancer that is difficult to be detected during routine screening. The only possible way for their discovery is through breast images preventive examinations, generally mammography, which usually occurs after age 45. Because of these factors, impalpable lesions are often discovered when the developmental stage of the disease is already advanced and therapeutic interventions are less aggressive.This study aimed to characterize impalpable tumors by the analysis of genetic (mutation and instability) and epigenetic (methylation of the promoter region) of DNA regions related to TP53 tumor suppressor gene from impalpable lesions extracted from biopsies of women living in the state of Rio de Janeiro. Were investigated 34 tissue samples from breast cancer by DNA sequencing in exons 5-8 of TP53. In this region, no mutation was found, this result may be related to the initial type of injury according to data of the radiological lesions of categories 3 and 4 of scale BIRADS . In order to check the status of methylation of the promoter region of the TP53 gene, we analyzed 30 pairs from samples (blood and tumor) of patients with suspected breast cancer, by MSPPCR technique. No tumor sample showed a change in the state of methylation in the promoter region of TP53 as compared to the normal sample. One possible reason for the disparity in the results between this study and the other studies may be related with the applied techniques. The characterization of the nonpalpable lesions just started this work in which we could verify that the mutation in TP53 may be a later event. Therefore, the breast lesion, in its different forms, remains the subject investigated by this group. We have been worked for expanding the number of samples, so as to link the new possibilities of molecular diagnostics in clinical practice in tumors and biological fluids

Orientador: José Moacir Marin / Banca: Sebastião Hetem / Banca: Patrícia Amoroso / Banca: Renata Camacho Miziara / Banca: Deny Munari Trevisani / Resumo: A aderência de bactérias patogênicas a receptores na superfície de . células epiteliais tem sido reconhecida como um importante evento inicial da colonização bacteriana. O principal mecanismo de patogenicidade da EPEC é uma lesão provocada pela sua aderência ao epitélio através do "attaching and effacing" (AlE), que é caracterizado pela íntima adesão da bactéria à célula do hospedeiro, esta adesão às microvilosidades do enterócito ocorre devido a formação de estruturas semelhantes a pedestais. O objetivo deste estudo foi desenvolver um modelo de infecção com a Escherichía calí enteropatogenica (EPEC) em camundongo do tipo mus musculus. A estes animais foram administrados um inoculo de 108 CFU de linhagens EPEC, sendo que a linhagem 3111-90 foi proveniente de cepas que podem causar diarréia infantil e as linhagens 537-1, 263, 304-3 e 988-2 foram provenientes de leite mastítico bovino. As linhagens foram introduzidas em camundongos com vinte dias de vida por via intraperitonial, e estes foram eutanasiados cinco horas após a inoculação. Como resultado através de cortes histológicos seriados, verificou-se que algumas das linhagens inoculadas levaram ao aparecimento de lesões suaves na mucosa intestinal, com a quebra da camada celular superficial da mucosa, aparecimento de células epiteliais com contornos irregulares e infiltração de células inflamatórias. / Abstract: The aim of this study was to develop a enteropathogenic Escherichia colí (EPEC) infection model in mice. An inoculum of 108 CFU of EPEC strains 3111-90 from infantile diarrhea; 537-1, 263,304-3 and 988-2 from bovine mastitic milk to newborn mice lead to a mildly damage in the intestinal mucosa with breaking in the superficial stratum, epithelial cells with irregular shape and a inflammatory cell infiltration. / Doutor

A infecção pelo Papilomavírus Humano (HPV) é a principal responsável pelo desenvolvimento de lesões intraepiteliais e, potencialmente, do câncer cervical (CC). A presença de fatores como inflamação e outros agentes infecciosos contribuem para a instalação e persistência do vírus. A inclusão da pesquisa do HPV e de outros agentes infecciosos relacionados junto a programas de rastreamento do CC ainda é controversa. Além disso, sabe-se que o processo inflamatório e as lesões celulares decorrentes da presença de HPV e seus cofatores provocam alterações na expressão de diversas proteínas, entre elas a S100A4, que poderia funcionar como biomarcador de exposição. Desta forma, foram analisadas amostras de esfregaços cervicais para investigação da relação do diagnóstico citológico com a presença de agentes infecciosos, além do padrão de expressão da proteína S100A4. Nossos resultados demonstraram que o aparecimento de lesões ou atipias citológicas apresentou associação com a presença de HPV, tanto na infecção simples como na infecção por múltiplos genótipos de alto risco oncogênico, sugerindo a pesquisa molecular do HPV complementar à citologia. A presença de infecção latente pelo HPV também foi observada, a qual deve ser acompanhada com exames citológicos periódicos. A infecção por Chlamydia trachomatis desempenha importante papel como cofator para o desenvolvimento do CC e foi prevalente na população estudada, demonstrando associação com a presença de diferentes genótipos de HPV. Tanto nas pacientes sintomáticas como nas assintomáticas houve a detecção de leveduras do gênero Candida, sendo que a mais prevalente foi a C. albicans apresentando-se sensível à Anidulafungina e Anfotericina B, na maioria dos casos, e resistente ao Fluconazol. Com relação à expressão da proteína S100A4, houve associação com as alterações citológicas características do HPV, nas quais houve redução de sua expressão à medida que aumentou o grau da lesão. No entanto, também observamos que há expressão fisiológica da proteína S100A4 no epitélio escamoso estratificado da ectocérvice que varia de acordo com o grau de maturação celular e a presença de alterações citológicas inflamatórias, onde foi demonstrado aumento da sua expressão. Portanto, a avaliação da expressão da proteína S100A4 pode auxiliar no diagnóstico precoce do câncer de colo do útero nas lesões intraepiteliais cervicais positivas para HPV. Analisando-se globalmente, estes resultados sugerem a inclusão da pesquisa molecular de HPV e C. trachomatis, bem como a identificação de leveduras do gênero Candida complementares à citologia esfoliativa junto a programas de rastreamento. Além disso, a proteína S100A4, mostrou-se promissora como biomarcador dos efeitos celulares dos fatores associados. Observa-se que a associação de diferentes metodologias permite a detecção precoce de lesões e, consequentemente, contribuem para a redução da incidência do CC. / Human papillomavirus (HPV) infection is the main responsible for the development of intraepithelial lesions and potentially cervical cancer (CC). The presence of factors such as inflammation and other infectious agents contribute to the onset and persistence of the virus. The inclusion of HPV research and other infectious agents associated in the CC screening programs is still controversial. In addition, it is known that inflammation and cell injury caused by the presence of HPV and their cofactors cause changes in gene expression and function of several proteins, including the S100A4 which could function as a biomarker of exposure. Thereby, samples of cervical specimens were analyzed to investigate the relationship of cytological diagnosis in the presence of infectious agents, other than the standard expression of S100A4 protein. Our results demonstrated that the development of lesions or cytological atypia was associated with the presence of HPV in either simple infection or infection by multiple genotypes of high oncogenic risk, indicating the importance of molecular HPV analysis complementary to cytology. The presence of latent infection was also observed and must be monitored with periodic cytological examinations. The Chlamydia trachomatis infection plays an important role as a cofactor for the development of CC and was prevalent in the population studied, demonstrating association with the presence of different HPV genotypes. For both symptomatic and asymptomatic patients there was a yeast detection of Candida, and the most prevalent was the Candida albicans presenting sensitive to Anidulafungin and Amphotericin B, in most cases, and resistant Fluconazole. Regarding the S100A4 protein expression, there was association with abnormal cytological HPV characteristics where a reduction of expression could be observed and the degree of injury increased. However, we also observed that there are physiological expression of S100A4 protein in the stratified squamous epithelium of the ectocervix and this varies according to the degree of cell maturation and the presence of inflammatory cell alterations, increased expression where demonstrated. Therefore, the evaluation of the expression of S100A4 protein may assist in the early diagnosis of cervical cancer in cervical intraepithelial lesions positive for HPV. Overall, these results suggest the inclusion of molecular research of HPV and C. trachomatis, and the identification of yeasts Candida complementary to exfoliative cytology in screening programs. In addition, the S100A4 protein has shown to be promising as a biomarker for cellular effects of associated factors. It was observed that the association of different methodologies allows early detection of lesions and therefore contribute to reducing the incidence of CC.

Background: Pulmonary arterial hypertension (PAH) is a lethal disease for which the fundamental molecular mechanisms are only partially understood. Existing therapies, which primarily focus on endothelial dysfunction, have limited effects on improving outcomes. Increases in pulmonary vascular resistance in PAH may be attributed to complex lung arterial remodeling which result in obliterative “plexiform” lesions, a pathological hallmark of this disease. Recent studies have shown that endothelial cell (ECs) apoptosis may be a central trigger for PAH, resulting in the emergence of growth-dysregulated and apoptosis-resistant ECs that contribute to the formation of complex neoplastic-like vascular lesions. However, the mechanism which links ECs apoptosis to dysregulated growth is not yet known. Previous studies in our lab have identified increased expression of translationally controlled tumor protein (TCTP) and its gene (TPT1), previously implicated in the transformation of neoplastic cells in cancer, and in blood outgrowth ECs from patients with PAH. Moreover, TCTP expression was found to be elevated in the lungs of patients with PAH, and tightly localized to complex arterial lesions. In addition, it was detected in obliterative intimal lesions of an experimental rat model of severe PAH. Hypothesis: TCTP represents a central molecular mechanism linking ECs apoptosis to the emergence of growth-dysregulated lung vascular cells and occlusive, complex arterial remodelling in PAH. Specific Hypotheses: - Lentiviral overexpression of TCTP in human umbilical vein endothelial cells (HUVECs) and pulmonary artery smooth muscle cells (PASMCs) leads to a hyperproliferative and apoptosis-resistant phenotype. - Overexpression of TCTP will increase its export into apoptotic extracellular vesicles, thereby augmenting cell-cell signalling between ECs and neighbouring SMCs. Purpose: My objective was to examine the effects TCTP overexpression on ECs and SMCs survival in terms of proliferation and apoptosis, and TCTP release on the survival of nontransduced ECs and SMCs. Methods and Results: The effect of TCTP overexpression on ECs growth and survival was studied using in vitro models. TCTP was overexpressed via a lentivirus vector in HUVECs and PASMCs. Compared to non-transfected or null transfected cells, TCTP overexpression led to increases in BrdU incorporation, consistent with hyper-proliferation, and decreases in caspase activity, consistent with apoptosis resistance. As well, TCTP was selectively exported into the conditioned media of apoptotic ECs, but not SMCs, despite similar levels of overexpression. In addition, the level of release was greater in serum starved conditioned media in comparison to the exosome fraction. Finally, our data demonstrates a selective effect of conditioned media (CM) from serum-starved ECs on PASMCs, but not ECs, in terms of an increase in proliferation and a decrease in apoptosis. Conclusions: These support the idea that TCTP overexpression confers an increase in the survival of SMCs and HUVECs. Moreover, TCTP released from apoptotic ECs leads to a growth-dysregulated phenotype within SMCs (but not ECs) and may contribute to the formation of complex lung arterial lesions, leading to arteriolar obliteration in PAH. Finally, an increase in the level of TCTP expression via lentiviral transduction led to an increased TCTP export into the media, but this appeared to be mostly in the soluble portion, and less was associated with exosomes.

Background: Pain is frequently reported by people with multiple sclerosis (MS). It has been associated with decreased quality of life, psychiatric morbidity, interference with day to day activities, and frequent healthcare attendance. It has been reported by people with multiple sclerosis to be one of their most important symptoms, and available treatments are limited in their effectiveness. Despite this, our understanding of the epidemiology and mechanisms of pain in people with MS are limited. Our understanding of the interactions of central nervous system mechanisms and pain states overall is growing. However, the application of this knowledge to MS is incomplete. Previous studies have shown that the descending pain modulatory system (DPMS) is an endogenous network of cortical and subcortical brain structures which act to limit, or accentuate, an individual’s perception of pain, via descending brainstem pathways. Associated clinical measures include depression, anxiety, and cognitive flexibility. Our understanding of the function or dysfunction of this system in MS is limited. We do not know if the MS disease process may adversely affect the structure or function of the DPMS. Hypothesis: In people with neuropathic limb pain in relapsing remitting MS (RRMS), compared to people with RRMS who do not have pain, there will be disruption of the endogenous descending pain modulatory system. This will manifest as impaired descending inhibition of pain. Aims and Methods Establishing the background using systematic reviews: The first aim of this thesis was to establish the prevalence, natural history and associations of pain (and pain syndromes) occurring in people with MS. The second aim was to explore existing knowledge of how the MS disease process may contribute to pain states, using a systematic review of neuroimaging studies. Prospective clinical study: A case-control study of 47 people with RRMS was then carried out. 31 of these had neuropathic pain in the limbs, and 16 did not have pain. Using targeted assessments, function of the descending pain modulatory system was assessed in the following ways: First: Detailed clinical, behavioural and neuropsychological assessment, focussing on cognitive, behavioural and affective features known to be closely related to the DPMS. Second: MRI imaging of brain structure, focussing on the volume and location of MS lesions, as well as the volume of key grey-matter structures involved in the DPMS. Third: Resting state functional MRI imaging of the brain, focussing on functional connectivity between the rostral anterior cingulate cortex and two other key DPMS structures (dorsolateral prefrontal cortex, and periaqueductal gray). Results: Systematic reviews: Meta-analysis of existing prospective studies confirmed that pain is very common in MS, affecting about 63% of people with MS on average (95%CI between 55 and 70%). Many different types of pain contribute to this overall estimate. No significant associations with disease course or stage emerged. Several neuroimaging studies have assessed people with MS-associated pain using MRI. These studies were often small, and with associated methodological issues. It is likely that location of MS lesions is implicated in aetiology of pain syndromes in some cases, though our overall knowledge is limited. Prospective study: In a prospective study, people with and without pain were matched for age and gender. Furthermore, groups were balanced for a range of other variables. The pain group more frequently received gabapentinoid medications. The presence of pain was significantly associated with increased scores for depression, fatigue and catastrophising, as well as with specific impairments at neuropsychological assessment, including cognitive flexibility. Many of these impairments are directly relevant to existing models of the DPMS. Overall volume of MS lesions was not different in people with pain, though lesions were more likely to occur in the brainstem. Some alterations of grey-matter volumes in people with pain which mirrored studies of pain disorders outside MS were found, but these did not involve structures key to the DPMS. Affected structures included trigeminothalamic nucleus (relative volume increase in pain group), posterior cingulate cortex and parahippocampal gyrus (volume decrease in pain group). Functional connectivity of the rostral anterior cingulate cortex to the periaqueductal grey matter, a key structure in the descending modulation of pain, was stronger in the group without pain. Conversely, functional connectivity to the dorsolateral prefrontal cortex, repeatedly implicated in the DPMS and thought to be involved in cognitive evaluation and flexibility, was stronger in the pain group. MS lesion volume appeared to account for some of this difference in a multivariate analysis. Limitations: Key limitations of this work include cross-sectional design, small sample size, and number of statistical comparisons carried out. Conclusions: Systematic reviews examined the prevalence, natural history and associations of pain in MS, as well as examining existing neuroimaging studies which investigated how the MS disease process could contribute to pain states. A prospective study found evidence of both emotional/affective and cognitive dysfunctions relevant to the hypothesis of dysfunction in the DPMS. Higher likelihood of MS lesions in the brainstem could be relevant to DPMS function. Separately, there were structural grey-matter volume alterations reflecting those found in many pain studies outside MS. Importantly, however, these did not affect key DPMS structures. Resting state functional MRI however demonstrated altered connectivity of core DPMS structures, which may be partly mediated by MS lesion volume. Functional connectivity findings could be consistent with the hypothesis of impaired descending pain inhibition, in people with relapsing remitting MS affected by neuropathic limb pain.