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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.
261

Applicazione della neurodiagnostica avanzata allo studio dei disturbi psicologici nelle malattie infiammatorie croniche intestinali

Agostini, Alessandro <1973> 12 April 2011 (has links)
Background and aim Ulcerative Colitis (UC) and Crohn’s Disease (CD), collectively labelled as inflammatory bowel disease (IBD), are idiopathic, chronic inflammatory disorder of the bowel with a remitting and relapsing course. IBD are associated to poor emotional functioning and psychological distress. We have investigated the brain involvement in patients with IBD using functional magnetic resonance imaging (fMRI). Materials and methods We developed an emotional visual task to investigate the emotional functioning in 10 UC patients and 10 healthy controls (HC). Furthermore, we have compared the brain stress response between a group of 20 CD patients and a group of 18 HC. Finally, we evaluated potential morphological differences between 18 CD patients and 18 HC in a voxel based morphometry (VBM) study. Results We found brain functional changes in UC patients characterized by decreased activity in the amygdala in response to positive emotional stimuli. Moreover, in CD patients, the brain stress response and habituation to stressful stimuli were significantly different in the medial temporal lobe (including the amygdala and hippocampus), the insula and cerebellum. Finally, in CD patients there were morphological abnormalities in the anterior mid cingulated cortex (aMCC). Conclusion IBD are associated to functional and morphological brain abnormalities. The previous intestinal inflammatory activity in IBD patients might have contributed to determine the functional and morphological changes we found. On the other hand, the dysfunctions of the brain structures we found may influence the course of the disease. Our findings might have clinical implications. The differences in the emotional processing may play a role in the development of psychological disorders in UC patients. Furthermore, in CD patients, the different habituation to stress might contribute to stress related inflammatory exacerbations. Finally, the structural changes in the aMCC might be involved in the pain symptoms associated to the bowel disorder.
262

Epigenetic control of the basal-like gene expression profile via Interleukin-6 in breast cancer cells

D’Anello, Laura <1980> 03 May 2011 (has links)
No description available.
263

Use of VEGFR-2 targeted microbubbles (BR55, Bracco imaging) for the early ultrasound evaluation of response to antiangiogenic treatment in a xenograft model of hepatocarcinoma

Baron Toaldo, Marco <1981> 25 March 2011 (has links)
Aim: To evaluate the early response to treatment to an antiangiogenetic drug (sorafenib) in a heterotopic murine model of hepatocellular carcinoma (HCC) using ultrasonographic molecular imaging. Material and Methods: the xenographt model was established injecting a suspension of HuH7 cells subcutaneously in 19 nude mice. When tumors reached a mean diameter of 5-10 mm, they were divided in two groups (treatment and vehicle). The treatment group received sorafenib (62 mg/kg) by daily oral gavage for 14 days. Molecular imaging was performed using contrast enhanced ultrasound (CEUS), by injecting into the mouse venous circulation a suspension of VEGFR-2 targeted microbubbles (BR55, kind gift of Bracco Swiss, Geneve, Switzerland). Video clips were acquired for 6 minutes, then microbubbles (MBs) were destroyed by a high mechanical index (MI) impulse, and another minute was recorded to evaluate residual circulating MBs. The US protocol was repeated at day 0,+2,+4,+7, and +14 from the beginning of treatment administration. Video clips were analyzed using a dedicated software (Sonotumor, Bracco Swiss) to quantify the signal of the contrast agent. Time/intensity curves were obtained and the difference of the mean MBs signal before and after high MI impulse (Differential Targeted Enhancement-dTE) was calculated. dTE represents a numeric value in arbitrary units proportional to the amount of bound MBs. At day +14 mice were euthanized and the tumors analyzed for VEGFR-2, pERK, and CD31 tissue levels using western blot analysis. Results: dTE values decreased from day 0 to day +14 both in treatment and vehicle groups, and they were statistically higher in vehicle group than in treatment group at day +2, at day +7, and at day +14. With respect to the degree of tumor volume increase, measured as growth percentage delta (GPD), treatment group was divided in two sub-groups, non-responders (GPD>350%), and responders (GPD<200%). In the same way vehicle group was divided in slow growth group (GPD<400%), and fast growth group (GPD>900%). dTE values at day 0 (immediately before treatment start) were higher in non-responders than in responders group, with statistical difference at day 2. While dTE values were higher in the fast growth group than in the slow growth group only at day 0. A significant positive correlation was found between VEGFR-2 tissue levels and dTE values, confirming that level of BR55 tissue enhancement reflects the amount of tissue VEGF receptor. Conclusions: the present findings show that, at least in murine experimental models, CEUS with BR55 is feasable and appears to be a useful tool in the prediction of tumor growth and response to sorafenib treatment in xenograft HCC.
264

L'attitudine alla comunicazione. Uno studio nel Corso di Laurea in Infermieristica

Tiraboschi, Andrea <1955> 12 April 2011 (has links)
It is believed that the way of being and the communicative-relational skills of every individual have multifactorial origins, including the quality of primary relationships with caregivers. For some time, the need for health care professionals to possess specific communicative and interpersonal skills has been highlighted. To the degree course in Nursing, like to all other degree programs related to health, access is granted to students who have large individual differences, both in terms of personality, and in terms of relational skills. Each academic year, therefore, the people responsible for the didactic organization of every course, are faced with having to prepare a training plan capable of addressing communicative-relational aspects and, at the same time, of being adequate to the real attitudes of incoming students. Thus, the need for appropriate tools for measuring the personological and vocational traits considered specific to health professions was born. This study has a twofold objective. On one hand, it aims at selecting a battery of psychological tests to detect psychological and attitudinal patterns, to facilitate the coordinators of graduate courses in their didactic organization and planning of educational training; on the other hand, it seeks to assess the correlations between communicative-relational skills (Relational-Communicative style, according to the model of patient-centered medicine-TRS) (Mucchielli’s Test of Spontaneous Attitudes – usual kind of attitude in dual relationships), personality traits (Alexithymia), styles of attachment to parental figures (PBI), and the capability of recognizing facial emotions, in a sample of students enrolled in the first year of a degree in Nursing.
265

Resident angiogenic mesenchymal stem cells from multiorgan donor thoracic aortas

Foroni, Laura <1978> 16 April 2008 (has links)
Stem cells are one of the most fascinating areas of biology today, and since the discover of an adult population, i.e., adult Stem Cells (aSCs), they have generated much interest especially for their application potential as a source for cell based regenerative medicine and tissue engineering. aSCs have been found in different tissues including bone marrow, skin, intestine, central nervous system, where they reside in a special microenviroment termed “niche” which regulate the homeostasis and repair of adult tissues. The arterial wall of the blood vessels is much more plastic than ever before believed. Several animal studies have demonstrated the presence of cells with stem cell characteristics within the adult vessels. Recently, it has been also hypothesized the presence of a “vasculogenic zone” in human adult arteries in which a complete hierarchy of resident stem cells and progenitors could be niched during lifetime. Accordingly, it can be speculated that in that location resident mesenchymal stem cells (MSCs) with the ability to differentiate in smooth muscle cells, surrounding pericytes and fibroblasts are present. The present research was aimed at identifying in situ and isolating MSCs from thoracic aortas of young and healthy heart-beating multiorgan donors. Immunohistochemistry performed on fresh and frozen human thoracic aortas demonstrated the presence of the vasculogenic zone between the media and the adventitial layers in which a well preserved plexus of CD34 positive cells was found. These cells expressed intensely HLA-I antigens both before and after cryopreservation and after 4 days of organ cultures remained viable. Following these preliminary results, we succeeded to isolate mesenchymal cells from multi-organ thoracic aortas using a mechanical and enzymatic combined procedure. Cells had phenotypic characteristics of MSC i.e., CD44+, CD90+, CD105+, CD166+, CD34low, CD45- and revealed a transcript expression of stem cell markers, e.g., OCT4, c-kit, BCRP-1, IL6 and BMI-1. As previously documented using bone marrow derived MSCs, resident vascular wall MSCs were able to differentiate in vitro into endothelial cells in the presence of low-serum supplemented with VEGF-A (50 ng/ml) for 7 days. Under the condition described above, cultured cells showed an increased expression of KDR and eNOS, down-regulation of the CD133 transcript, vWF expression as documented by flow cytometry, immunofluorescence, qPCR and TEM. Moreover, matrigel assay revealed that VEGF induced cells were able to form capillary-like structures within 6 hours of seeding. In summary, these findings indicate that thoracic aortas from heart-beating, multi-organ donors are highly suitable for obtaining MSCs with the ability to differentiate in vitro into endothelial cells. Even though their differentiating potential remains to be fully established, it is believed that their angiogenic ability could be a useful property for allogenic use. These cells can be expanded rapidly, providing numbers which are adequate for therapeutic neovascularization; furthermore they can be cryostored in appropriate cell banking facilities for later use.
266

Vascular wall stem cells. Selection and conditioning of progenitors useful for cell therapy. A pathological case study

Valente, Sabrina <1980> 20 April 2010 (has links)
The arterial wall contains MSCs with mesengenic and angiogenic abilities. These multipotent precursors have been isolated from variously-sized human adult segments, belying the notion that vessel wall is a relatively quiescent tissue. Recently, our group identified in normal human arteries a vasculogenic niche and subsequently isolated and characterized resident MSCs (VW-MSCs) with angiogenic ability and multilineage potential. To prove that VW-MSCs are involved in normal and pathological vascular remodeling, we used a long-term organ culture system; this method was of critical importance to follow spontaneous 3-D vascular remodeling without any influence of blood cells. Next we tried to identify and localize in situ the VW-MSCs and to understand their role in the vascular remodeling in failed arterial homografts. Subsequently, we isolated this cell population and tested in vitro their multilineage differentiation potential through immunohistochemical, immunofluorescence, RT-PCR and ultrastructural analysis. From 25-30cm2 of each vascular wall homograft sample, we isolated a cell population with MSCs properties; these cells expressed MSC lineage molecules (CD90, CD44, CD105, CD29, CD73), stemness (Notch-1, Oct-4, Sca-1, Stro-1) and pericyte markers (NG2) whilst were negative for hematopoietic and endothelial markers (CD34, CD133, CD45, KDR, CD146, CD31 and vWF). MSCs derived from failed homografts (H-MSCs) exhibited adipogenic, osteogenic and chondrogenic potential but scarce propensity to angiogenic and leiomyogenic differentiation. The present study demonstrates that failed homografts contain MSCs with morphological, phenotypic and functional MSCs properties; H-MSCs are long-lived in culture, highly proliferating and endowed with prompt ability to differentiate into adipocytes, osteocytes and chondrocytes; compared with VW-MSCs from normal arteries, H-MSCs show a failure in angiogenic and leiomyogenic differentiation. A switch in MSCs plasticity could be the basis of pathological remodeling and contribute to aneurysmal failure of arterial homografts. The study of VW-MSCs in a pathological setting indicate that additional mechanisms are involved in vascular diseases; their knowledge will be useful for opening new therapeutic options in cardiovascular diseases.
267

Rinoplastia experimental com enxerto autógeno de costela de cães

Santos Junior, Eduardo de Bastos January 2005 (has links)
A rinoplastia é a cirurgia plástica da cavidade nasal, que é muito difundida na medicina humana por motivos estéticos. Os animais possuem doenças que exigem cirurgia na cavidade nasal e na espécie canina pouco foi estudado com relação a rinoplastia. Algumas lesões causadas por traumatismo, tumores, fungos e reações inflamatórias crônicas, podem causar destruição de tecidos, sendo necessária a reconstituição do local. O uso de enxertos em animais é bastante difundido, principalmente os ósseos. No presente trabalho estudou-se o uso de costela autógena para correção de defeito criado em osso nasal em cães. O experimento foi realizado na Faculdade de Veterinária da Universidade Federal do Rio Grande do Sul. Utilizou-se 15 animais, separados em três grupos de pós-operatório onde após 30, 60 e 90 dias finalizavam-se seus acompanhamentos. Cada grupo era composto de quatro animais enxertados e um animal controle onde se utilizava o material do próprio defeito criado para coaptação. Os animais foram acompanhados clinicamente, a integração do enxerto foi avaliada com exames radiográficos obtidos a cada 15 dias até o final de seu acompanhamento pós-operatório. A histopatologia foi realizada no último dia de acompanhamento, conforme a distribuição dos animais nos grupos. Os resultados mostraram que a técnica cirúrgica é de fácil execução e possui praticidade em seu uso. O emprego da costela foi suficiente para cobertura de todos defeitos criados. O efeito estético foi excelente. Os exames radiográficos comprovaram a integração do enxerto e a avaliação histopatológica evidenciou a presença de células compatíveis com a viabilização da técnica proposta. Sendo possível então o uso de enxerto autógeno de costela para reconstrução de defeito criado experimentalmente em dorso nasal de cães.
268

Avaliação dos mecanismos adquiridos de resistência a antimicrobianos em enterobactérias produtoras de carbapenemases por sequenciamento de nova geração

Nodari, Carolina Silva January 2016 (has links)
O objetivo deste trabalho foi caracterizar os mecanismos adquiridos de resistência de isolados de enterobactérias produtoras de carbapenemases utilizando a tecnologia de sequenciamento de nova geração. Foram incluídos no estudo quatro isolados – três Escherichia coli e uma Serratia marcescens – produtores de diferentes carbapenemases – OXA-370, KPC-2, NDM-1 e GES-5, respectivamente, obtidos a partir de um estudo de vigilância para detecção de carbapenemases. O DNA total dos isolados foi extraído utilizando kits comerciais e submetido à fragmentação enzimática para a obtenção de bibliotecas genômicas de aproximadamente 300 pares de bases. Após a preparação das bibliotecas, elas foram carregadas em chips 316 v2 para a plataforma Ion Torrent PGM e submetidas ao sequenciamento, utilizando um programa de 850 flows. Para cada genoma, foram obtidos aproximadamente um milhão de reads, os quais foram submetidos ao processo de montagem para a obtenção de genomas de aproximadamente 5Mb com uma cobertura de, em média, 175 vezes. As sequências obtidas foram submetidas à anotação utilizando o sistema RAST e a ferramenta online ResFinder. Sequências de inserção foram pesquisadas utilizando a ferramenta ISFinder. Além das carbapenemases, genes que codificam para outras β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) foram encontrados em todos os genomas. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic), bem como genes que codificam resistência às sulfonamidas e ao trimetoprim também foram comuns aos isolados avaliados. Os seguintes ambientes genéticos foram observados: blaOXA-370 é flanqueada pela IS5075-like, blaKPC-2 está inserida no transposon Tn4401, e blaNDM-1, no transposon Tn3000. Cada isolado de E. coli pertenceu a um sequence type (ST) distinto: 1099F pertence à ST617, 1326F, à ST648, e 2610F, à ST707. Nossos resultados indicaram a diversidade de genes de resistência que podem ser encontrados em um isolado clínico, ressaltaram a variedade de contextos genéticos em que as carbapenemases podem estar inseridas e demonstraram que o sequenciamento de nova geração pode ser utilizado como uma ferramenta para a caracterização de isolados bacterianos multirresistentes, auxiliando, entre outros aspectos, na tipagem e na identificação de determinantes de resistência. / The aim of this study was to characterize the resistome of carbapenemase-producing Enterobacteriaceae using a next-generation sequencing platform. Four isolates were included in this study – three Escherichia coli and one Serratia marcescens – producing different carbapenemases – OXA-370, KPC-2, NDM-1 and GES-5, respectively, obtained from a surveillance study for carbapenemase detection. Total DNA was extracted using commercially available kits and submitted to enzymatic fragmentation to obtain libraries of around 300 base pairs of each isolate. After library preparation, they were loaded in 316 v2 chips for Ion Torrent PGM platform, and sequencing was performed using an 850 flows program. For each genome, approximately a million reads were obtained, and they were further assembled. The genome length for each isolate was of around 5Mb, with a mean coverage of 175x. The RAST system and the online tool ResFinder were used for annotation, as well as ISFinder. Besides the carbapenemases, genes encoding for other β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) were found in all genomes. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic) were also detected in every isolate included in the study, as well as genes encoding for resistance determinants to sulfonamides and trimetoprim. The genetic environment of the carbapenemases was very similar to other isolates described in the literature – blaOXA-370 is flanked by IS5075-like, blaKPC-2 is inserted in transposon Tn4401, and blaNDM-1 was found in transposon Tn3000. Each isolate belonged to a distinct ST – 1099F is part of ST617, 1326F belonged to ST648 and 2610F, to ST707. Our results demonstrated the diversity of resistance determinants that can be found in a clinical isolate, highlighted the variability of genetic environments in which carbapenemases can be present and demonstrated that next-generation sequencing is a valuable tool for the characterization of multidrug-resistant isolates, and can provide information regarding the molecular typing and the identification of resistance determinants.
269

O raciocinio clinico e os equipamentos medicos: subsidios para a compreensão do significado dos equipamentos diagnostico-terapeuticos para a medicina

Blank, Nelson January 1985 (has links)
Dissertação (mestrado) - Universidade do Estado do Rio de Janeiro, Instituto de Medicina Social / Made available in DSpace on 2012-10-15T23:47:36Z (GMT). No. of bitstreams: 0
270

Raciocínio clínico no diagnóstico médico

Stamm, Ana Maria Nunes de Faria January 2007 (has links)
Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção / Made available in DSpace on 2012-10-23T08:43:23Z (GMT). No. of bitstreams: 1 241054.pdf: 5221121 bytes, checksum: 47fc54981ae7596b9ac9d2be2f8b936d (MD5) / Esse estudo teve como objetivo identificar o processo de raciocínio clínico na elaboração de hipóteses diagnósticas, contextualizado a um tema protótipo em Clínica Médica (CM), tendo como pressuposto que a estratégia hipotético-dedutiva é a base do raciocínio clínico e a esquema-indutiva e o reconhecimento de um padrão são estratégias auxiliares ou combinadas. O delineamento foi transversal, com base epistemológica qualitativa, com amostra não-probabilística do tipo intencional. Foi realizado no Hospital Universitário, da UFSC, em Florianópolis - SC, com 30 médicos-professores de um Departamento de Ensino em CM, que exercem ou exerceram atividade clínica por mais de 5 anos. A construção de protótipos em CM pelos participantes permitiu selecionar um caso clínico real, que foi o estímulo para a aplicação da técnica "think aloud" ou "pensando em voz alta". O texto obtido do processo de raciocínio clínico com a verbalização dos participantes foi gravado, transcrito e analisado com a aplicação da técnica de análise temática, do método de análise de conteúdo; para o perfil profissional foi aplicado um questionário estruturado. A estratégia de raciocínio mais freqüente foi a hipotético-dedutiva (HD) (47% (72/153)), com a mesma freqüência para a esquema-indutiva (E-I) (15,6% (24/153)) e o reconhecimento de um padrão (RP) (15,6%(24/153)), seguida pela mista E-I (E-I + HD) e mista RP (RP + HD) (respectivamente, 11,7% (18/153) e 9,8% (15/153), ao estabelecerem 153 hipóteses dentro de 31 tipos distintos. Concomitantemente, foram criados 356 eixos semânticos inseridos em 135 tipos, e os dados processados com 515 interpretações e 290 combinações. O perfil geral da amostra mostrou expressivo tempo de exercício na atividade clínica (27,3 anos) e na docência (24,4 anos), com uma média de especialização latu sensu de 2,3/participante, e mais da metade (53% (16/30) com strictu sensu. Os médicos-professores têm conhecimento formal e tácito diferenciado, com organização e conteúdo, utilizando múltiplas e combinadas estratégias no processo de raciocínio clínico, no qual a estratégia HD é a base. The objective of this study is to identify the clinical reasoning process in the elaboration of the diagnoses hypothesis, inserted in a prototype subject in Medical Clinic (MC), having as presupposition that the hypothetic deductive strategy, is the base of the clinical reasoning, and the inductive-scheme and the pattern recognition are auxiliaries or combined strategies. The outline was cross-sectional, with epistemological qualitative basis, using non-probabilistic sample of intentional type. This research was done in the Hospital from Santa Catarina Federal University, in Florianopolis, Santa Catarina State, with thirty teachers from the Medical Clinic (MC) Teaching Department, which perform or performed the clinical activity for more than five years. The prototype definition in MC by the participants, allow selecting a real clinical case, which was stimulated to apply a think aloud technique. The text gathered from the clinical reasoning process with the participant's verbal stimulation was taped, transcribed and analysed with the application of the thematic analysis technique, this analysis used the content analysis method, for the professional profile was applied a structured questionnaire. The more frequent reasoning strategy was hypothetic-deductive (HD) (47% (72/153)), the inductive-scheme (IE) (15.6% (24/153)) and the recognition of a standard (RS) (15.6% (24/153)) have the same frequency, followed by the mixed IE (IE + HD) and the mixed RS (RS + HD), (respectively, 11.7% (18/153) and 9.8% (15/153)), which established 153 hypothesis into 31 different types. At the same time, was created 356 semantic axis into 135 types, and these dates were processed with 515 interpretations and 290 combinations. The sample general profile showed an expressive time of the clinical activity experience (27.3 years) and in the medical teaching (24.4 years), with a latu sensu specialization average of the 2.3 years/ participant, and more than a half (53%) with strictu sensu. The doctors-teachers as formal and tacit knowledge, with the organization and content, using multiple and combined strategies in the clinical reasoning process, in which the HD strategy is the basis.

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