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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.
651

Efeito da metformina no remodelamento miocárdico e renal em ratos obesos com resistência à insulina / Effect of metformin on myocardial and renal remodeling in obese rats with insulin resistance

Adriana Burlá Klajman 03 June 2011 (has links)
Diversas evidências comprovam que a obesidade está associada a alterações estruturais e funcionais do coração em modelos humanos e animais. Outros estudos recentes também demonstram que a obesidade humana está associada com alterações na função e na estrutura vascular, especialmente em grandes e médias artérias. Estudos epidemiológicos têm confirmado que a obesidade é um fator de risco significativo para o aparecimento de proteinúria e de doença renal terminal em uma população normal. Com o objetivo de determinar as alterações morfológicas relacionadas ao remodelamento cardíaco, vascular e renal em um modelo experimental de obesidade induzida pelo glutamato monossódico (MSG) e os efeitos da metformina sobre estes achados, foram estudados 25 ratos divididos em cinco grupos: controle com 16 e 22 semanas (CON-16 e CON-22); obeso com 16 e 22 semanas (MSG-16 e MSG-22) e obeso + metformina (MET-22) 300mg/Kg/dia por via oral. A caracterização da resistência à insulina foi feita através da medida da insulina plasmática e cálculo do índice de HOMA-IR. As análises morfológicas e quantificação do colágeno miocárdico foram feitos pelo sistema de imagem Image Pro Plus analysis. A pressão arterial sistólica foi levemente maior no grupo MSG-22, adquirindo significância estatística quando comparada com o grupo MSG-16 (1222 vs 1082 mmHg, p<0,05). Por outro lado, o grupo MET-22 mostrou níveis mais baixos de pressão arterial (1181 mmHg), sem alcançar diferença significativa. No grupo de animais obesos, foi observado aumento na relação média-lumen com 16 semanas (39,93,7 vs 30,22,0 %, p<0,05) e com 22 semanas (39,81,3 vs 29,51,2%, p<0,05), que foi reduzida com o uso da metformina (31,50,9%). O depósito de colágeno na área perivascular no ventrículo esquerdo foi significativamente maior no grupo MSG-22 (1,390,06 vs 0,830,06 % no CON-22, p<0,01), sendo atenuado pela metformina (1,020,04%). No rim, a área seccional transversa das arteríolas intrarrenais foi semelhante entre os grupos (18,52,2 no CON-16; 19,93,7 no MSG-16; 18,93,1 no CON-22; 21,81,5 no MSG-22; 20,21,4 no MET-22). Foi observado aumento da área glomerular no grupo MSG-22 (141,34,5 vs 129,50,5 m2), mas sem significância estatística. Em conclusão, nos ratos com obesidade induzida pelo MSG, com resistência à insulina, as alterações cardíacas foram mais proeminentes do que as alterações renais. No coração foram observados sinais de remodelamento vascular hipertrófico nas pequenas artérias intramiocárdicas e evidências de fibrose miocárdica mais proeminente na área perivascular, alterações que foram, pelo menos parcialmente, atenuadas com o uso de metformina durante seis semanas, mostrando que esta droga pode ser benéfica na prevenção de complicações cardíacas, vasculares e renais associadas com a obesidade. / Many evidences show that obesity is associated to structural and functional changes in the heart of human and animal models. Recent studies also show that human obesity is associated with vascular structural and functional modifications, specially at large and medium-sized arteries. Epidemiological studies have confirmed that obesity is a significant risk factor for the development of proteinuria and end-stage renal disease in a normal population. With the objective to determinate morphological changes related to cardiac, vascular and renal remodeling in an experimental model of monosodium glutamate (MSG)-induced obesity and the effect of metformin at this finding. Twenty five rats were studied and divided into five groups: control with 16 e 22 weeks (CON-16 and CON-22); obese with 16 and 22 weeks (MSG-16 e MSG-22), and obese + metformin (MET-22) 300mg/Kg/day per oral. The characterization of insulin resistance was done through measurement of plasma insulin and calculation of HOMA-IR index. The morphological analysis and the quantification of myocardial collagen were carried out by Image Pro Plus analysis system. The systolic blood pressure was slightly higher in MSG-22 group, reaching statistical significance when compared to MSG-16 group (1222 vs 1082 mmHg, p<0.05). On the other hand, the MET-22 group demonstrated lower blood pressure levels (1181 mmHg), without reaching statistical difference. The obese animals presented increase in media-to-lumen ratio with 16 weeks (39.93.7 vs 30.22.0 %, p<0.05) and with 22 weeks (39.81.3 vs 29.51.2%, p<0.05), which was reduced with use of metformin (31.50.9%). The collagen deposition in perivascular area of left ventricle was significantly greater in MSG-22 group (1.390.06 vs 0.830.06 % in CON-22, p<0.01), and attenuated by metformin (1.020.04%). In the kidney, the media cross-sectional area of intrarenal arterioles was similar among the groups (18.52.2 in CON-16; 19.93.7 in MSG-16; 18.93.1 in CON-22; 21.81.5 in MSG-22; 20.21.4 in MET-22). An increase of glomerular area was observed in MSG-22 group (141.34.5 vs 129.50.5 m2), but without statistical significance. In conclusion, rats with MSG-induced obesity and insulin resistance presented more pronounced cardiac changes than renal alterations. In the heart, there were evidences of hypertrophic vascular remodeling were observed in intramyocardial small arteries and perivascular fibrosis. These findings were, at least partially, attenuated by metformin for six weeks, suggesting that this drug may be beneficial for prevention of cardiac, vascular and renal complications associated with obesity.
652

Towards an integral metatheory of addiction

Du Plessis, Guy Pierre 11 1900 (has links)
Addiction is one of the most significant problems facing contemporary society. Consequently many scholars, institutions and clinicians have sought to understand this complex phenomenon, as is evident in the abundance of etiological models of addiction in existence today. A literature review pointed that there is little consensus regarding the nature and etiopathogenesis of addiction, and integrative models have not yet been able to provide the sought-after integration. In addressing this problem, this study offers a theoretical analysis of the paradigmatic and meta-paradigmatic suitability of Integral Theory in the design of an integrated metatheory of addiction. The data consisted of the most prominent etiological theories and models of addiction. The study focused on several essential features constituting the architectonic of any metatheory that attempts to provide conceptual scaffolding for the construction of a comprehensive metatheory of addiction. The criteria for the construction of a metatheory were conceptual integration, ontological span, ontological depth, empirical validity and internal consistency. Integral Theory was critically assessed in terms of each of the abovementioned criteria. The study suggests that Integral Theory is eminently suitable as a philosophical foundation for the development of an integrated metatheory of addiction. / Psychology / M. A. (Psychology)
653

Recurrent, Pruritic Dermal Plaques and Bullae. Diagnosis: Eosinophilic Cellulitis (Wells Syndrome)

Green, W H., Yosipovitch, Gil, Pichardo, Rita O. 01 June 2007 (has links)
No description available.
654

Knowledge of the the hypertensive person regarding prevention strategies for coronary heart disease

Boulle, Adri 03 1900 (has links)
Dissertation / The aim of this study was to determine the knowledge of persons with hypertension in a selected geographical area regarding cardiovascular risk factors in order to make recommendations for patient education. A quantitative, non-experimental, descriptive study was done in the form of a survey using a questionnaire as measuring instrument. The population was hypertensive patients from selected private medical practices in the western part of KwaZulu-Natal and the bordering eastern part of the Free State. Convenience sampling was used and 46 respondents participated in the study. Only 16 (35%) of the respondents achieved a percentage on or above the competency indicator of 50%. Respondents performed worst in questions where definitions, for example hypertension, were assessed. Recommendations for a patient education document, nursing practice and further research were made. / Health Studies / M.A. (Health Studies)
655

Ris, skäver och skärva : Folklig kategorisering av några barnsjukdomar ur ett kognitivt semantiskt perspektiv

Westum, Asbjörg January 1999 (has links)
In Swedish dialects we find the terms ris,skäver and skärva referring to illnesses in children. The words are also parts of various compounds which refer to variants of the illnesses. The terms are linguistic expressions denoting two folk categories of illnesses, RIS and SKÄVER/SKÄRVA. These categories are investigated from a cognitive semantic perspective. The cognitive perspective argues that we organize our understanding of reality by using Idealized Cognitive Models (ICM) based on our physical, mental and emotional experiences of the world. The aim is twofold: to demonstrate the bases on which an experienced illness is placed in a certain category, and to show how a folk conception of illness is reflected in the word formation strategies. The word formation strategies emanate from notions of characteristic symptoms, and from notions of causes of illnesses. Both categories, RIS and SKÄVER/SKÄRVA, are based on a number of ICM's. The category RIS is a radial structure, which means that the category is held together although its members have no structural criteria in common. The category SKÄVER/SKÄRVA is a concentrating structure, meaning that all members share all structural criteria. There is a strong connection between word formation strategies and the structures of the categories. Terms related to symptoms refer to members of a category which are part of a radial structure, while terms related to causes refer to members of a category which are part of a concentrating structure. This can be explained by two of the basic assumptions of cognitive semantics: semantic content is structred and symbolized overtly on the surface form of a language and categories are conventional, based on cultural assumptions about the world. / digitalisering@umu
656

Neurofiziološki aspekt prvog gubitka svesti kod dece / Neurophysiological aspect of the first loss of consciousness in children

Peričin Starčević Ivana 15 September 2016 (has links)
<p>Uzroci gubitka svesti su različiti i te&scaron;ko ih je diferencirati. Razlikovanja epileptičkih od neepileptičkih gubitaka svesti je od krucijalnog značaja za ispitivanje, lečenja i prognoze ovih poremećaja. Elektroencefalografija (EEG) je standardna, neinvazivna metoda koja se koristi u ispitivanju nakon gubitka svesti. Inicijalni EEG nalaz nakon prvog gubitka svesti može biti normalan, specifičan ili nespecifičan. Procenat patolo&scaron;kog EEG nalaza je veći kod rano urađenog EEG pregleda. Kod dece rani EEG pregled u roku od 48h ne pokazuje statistički značajne abnormalnosti. Spontanim spavanjem ili EEG pregledom nakon deprivacije spavanja se beleži značajno veća prisutnost epileptiformnih promena kod dece starije od 3 godine, čak i kada je prvi EEG u budnom stanju normalan. Kombinacijama pregleda u budnom stanju i spavanju povećava prisutnost patolo&scaron;kih promena u EEG zapisu. Materijal metode: Istraživanje je obuhvatilo 198 dece uzrasta od 3-12 godine života nakon prvog gubitka svesti. Ispitanici su klasifikovani u dve grupe na osnovu otpusne dijagnoze: na grupu dece kod kojih dijagnoza epilepsije nije postavljena i na grupu dece kod kojih je dijagnoza epilepsije potvrđena. Korelirani su nalazi EEG-a u budnom stanju i spavanju (spontanom ili nakon deprivacije spavanja) sa anamnestičkim i kliničkim podacima o gubitku svesti, podacima o dužini trajanja gubitka svesti i vremena oporavka, vremenom kada je urađen prvi EEG u odnosu na gubitak svesti kao i sa podacima o ličnoj i porodičnoj anamnezi, a koji su navedeni u protokolu istraživanja. Ispitanici su potom podeljeni prema uzrastu u pet grupa u intervalima od 2 godine (3-4; 5-6; 7-8; 9-10; 11-12). Rezultati: Nakon prvog gubitka svesti specifičan (epileptiformni) nalaz EEG u budnom stanju imalo je 41,97% ispitanika, a 58,03% je imalo nespecifičan ili uredan EEG nalaz u budnom stanju, dok je specifičan nalaz EEG u spavanju imalo je 73,57% ispitanika, a 26,43% je imalo nespecifičan ili uredan EEG nalaz u spavanju. Ispitanici koji su imali specifičan EEG nalaz u budnom stanju imali su i specifičan nalaz u spavanju, a 45,07%, nakon deprivacije sna. Ispitanici koji su u budnom stanju imali nespecifičan ili uredan EEG nalaz u budnom stanju su u 35,92% nakon deprvacije spavanja imali specifičan EEG nalaz u spavanju, za razliku od 1,41% dece koji su imali specifičan EEG nalaz u spontanom spavanju. Sumarno gledano bolesnici koji su &ldquo;aktivirani&rdquo; odnosno oni kod kojih je deprivacija spavanja uticala na dobijanje specifičnog nalaza (epileptiformnih pormena) u spavanju čine 37.32% od svih ispitanika sa specifičnim (epileptiformnim) promenama u EEG-u u spavanju Zaključak: Kod većine pacijenata nakon prvog gubitka svesti EEG nalaz u budnom stanju je bio nespecifičan ili uredan. Procenat specifičnih EEG nalaza (epileptiformnih promena) se značajno povećao prilikom snimanja EEG u spavanju. Naročito velika korist od deprivacije spavanja kao metode aktivacije potvrđena kod onih pacijenata koji su imali inicijalni EEG u budnom stanju uredan ili nespecifičan. Dobijeni rezultati nesumljivo ukazuju na efikasnost deprivacije spavanja kao provokacione metode i povećanja procenta interiktalnihepileptiformnih EEG promena. Neprovociranih prvi gubitci svesti su se če&scaron;će javljali u grupi dece kod kojih je dijagnoza epilepsije potvrđena, dok su se provocirani gubitci svesti javljali če&scaron;će u grupi dece kod kojih dijagnoza epilepsije nije postavljena. Uzrast dece nije uticao na postavljanje dijagnoze epilepsije kao ni na inicijalne nalaze EEGa u budnom stanju i spavanju ali se registrovalo povećanje specifičnih nalaza (epileptiformnih promena) EEG-a, nakon deprivacije spavanja , sa porastom godina života.</p> / <p>The reasons for the loss of consciousness are various and difficult to be differentiated. It is of utmost importance to differentiate between epileptic and non-epileptic losses of consciousness for the purpose of testing, treating and giving prognosis related to this disorder. Electroencephalography (EEG) is a standard, non-invasive method used in testing after the loss of consciousness. The initial EEG after the first loss of consciousness can be normal, specific and non-specific. The percentage of pathological EEG findings is higher in EEG exams performed at an earlier stage. In children, an early EEG exam within 48 hours does not reveal any statistically relevant abnormalities. Spontaneous sleeping or an EEG examination after sleep deprivation leads to a significantly higher number of epileptiform changes in children above the age of 3, even in cases when the first EEG in the awake state was normal. Combinations of examinations in the awake state and during sleep lead to an increased presence of pathological changes in the EEG recording. Material and methods: The research included 198 children aged 3-12 who have experienced their first loss of consciousness. The subjects were classified into two groups, based on their discharge diagnosis: children who have not been diagnosed with epilepsy and children who have had epilepsy confirmed. A correlation was established between EEG findings in the awake state and sleep (spontaneous or following sleep deprivation) and medical history and clinical data related to the loss of consciousness, the information about the length of the loss of consciousness and recovery time, the time when the first EEG examination was performed in relation to the loss of consciousness, as well as the data from the personal and family history. The subjects were further divided into five groups, depending on their age, with each group covering a 2-year period (3-4; 5-6; 7-8; 9-10; 11-12). Results: Following the first loss of consciousness, specific (epileptiform) EEG findings were noticed in 41.97% subjects, while 58.03% of them had non-specific, i.e. regular findings in the awake state. When it comes to the findings during sleep, 73,57% were specific, while 26,43% were non-specific, i.e. regular. The subjects who had specific EEG findings in the awake state also had specific findings during sleep, while that percentage was 45,07% after sleep deprivation. The subjects who had non-specific, i.e. regular EEG findings in the awake state had specific EEG findings during sleep in 35.92% of the cases following sleep deprivation, while 1.41% of the children had specific EEG findings during spontaneous sleep. In total, the patients who were &ldquo;activated&rdquo;, i.e. those whose sleep deprivation contributed to specific findings (epileptiform changes) during sleep comprise 37.32% of all subjects with specific (epileptiform) changes in the EEG findings during sleep. Conclusion: In most patients suffering from the first loss of consciousness the EEG findings were non-specific, i.e. regular. The percentage of specific EEG findings (epileptiform changes) was significantly increased when the EEG examination was performed during sleep. Sleep deprivation, as an activation method, was particularly useful in patients whose initial EEG findings in the awake state were regular, i.e. non-specific. The results obtained undoubtedly confirm the efficiency of sleep deprivation as a provoking method and the increase of the percentage of interictal epileptiform EEG changes. Unprovoked first losses of consciousness were more common in the group of children who have had the diagnosis of epilepsy confirmed, while provoked losses of consciousness were more common in the group of children who have not been diagnosed with epilepsy. The age of children did not affect the process of establishing a diagnosis of epilepsy, nor did it affect the initial EEG findings in the awake state or during sleep, but it was observed that the number of specific EEG findings (epileptiform changes) following sleep deprivation increased with the increase of the age of the patients.</p>
657

Knowledge of the the hypertensive person regarding prevention strategies for coronary heart disease

Boulle, Adri 03 1900 (has links)
Dissertation / The aim of this study was to determine the knowledge of persons with hypertension in a selected geographical area regarding cardiovascular risk factors in order to make recommendations for patient education. A quantitative, non-experimental, descriptive study was done in the form of a survey using a questionnaire as measuring instrument. The population was hypertensive patients from selected private medical practices in the western part of KwaZulu-Natal and the bordering eastern part of the Free State. Convenience sampling was used and 46 respondents participated in the study. Only 16 (35%) of the respondents achieved a percentage on or above the competency indicator of 50%. Respondents performed worst in questions where definitions, for example hypertension, were assessed. Recommendations for a patient education document, nursing practice and further research were made. / Health Studies / M.A. (Health Studies)
658

Contribution à la validation du modèle cognitif du trouble obsessionnel- compulsif : le rôle des expériences de l’enfance et des états affectifs

Careau, Yves 03 1900 (has links)
Depuis une vingtaine d’années, le modèle cognitif basé sur les interprétations (Groupe de recherche sur la cognition dans le trouble obsessionnel compulsif [OCCWG], 1997, 2001, 2003, 2005) représente le modèle psychologique de l’étiologie et du maintien du TOC le plus étudié au plan empirique. Cependant, peu de recherches ont porté sur les deux postulats importants du modèle touchant respectivement le développement des croyances liées à l’obsessionnalité et la contribution des états affectifs au maintien des interprétations et des croyances (réactivité cognitive). L’objectif de cette thèse est de contribuer à la validation empirique de ces postulats. Fondé sur un devis corrélationnel dans un échantillon de participants mixte (participants troubles obsessionnels-compulsifs et participants non cliniques), le premier article étudie les liens entre les expériences de l’enfance et la présence de croyances obsessionnelles chez l’adulte. Deux modèles alternatifs sont comparés qui représentent d’une part un lien spécifique, et d’autre part un lien non spécifique entre les expériences de l’enfance et les croyances obsessionnelles adultes. Les résultats suggèrent la présence à la fois de relations spécifiques et non spécifiques entre les expériences de l’enfance et les croyances adultes. Les expériences de l’enfance et les domaines de croyance obsessionnels qui montrent des liens spécifiques sont ceux relatifs à la responsabilité, à la perception du danger, et au perfectionnisme. En contrepartie, les expériences de l’enfance relatives à la perception de danger et dans une moindre mesure la sociotropie, apparaissent étroitement liés à la plupart des domaines de croyances adultes (intolérance à l’incertitude, surestimation du danger, importance et contrôle des pensées). Dans la seconde étude, nous nous intéressons à la mesure et l’analyse longitudinales de la réactivité cognitive telle qu’elle s’exprime dans l’environnement naturel de huit participants troubles obsessionnels-compulsifs de type ruminateur. Par le biais de huit protocoles à cas uniques intensifs, l’analyse de contingence entre les scores quotidiens d’humeur (4 états émotionnels cotés par participant) et d’interprétations (une interprétation idiographique des intrusions par participant) permet d’établir une mesure de l’importance de la réactivité cognitive chez chaque participant. Ces résultats sont ensuite analysés du point de vue des postulats principaux de deux modèles spécifiques de la réactivité cognitive (modèle de l’Infusion de l’affect [Forgas, 2008] et modèle de l’Humeur comme intrant [Meeten & Davey, 2011]. Ainsi, les analyses intra-individuelles répétées trans-comportements) et interindividuelles (trans-participants) permettent d’illustrer le rôle proximal déterminant des stratégies de traitement de l’information (traitement systématique; traitement superficiel; traitement altéré) employées par les participants. En résumé, les résultats obtenus dans ces deux études fournissent des données utiles à la poursuite de la validation du modèle des interprétations du TOC. Dans la première étude, l’identification de liens spécifiques entre les EE et les croyances obsessionnelles soutient la séquence étiologique postulée, alors que l’identification de liens non spécifiques suggère que d’autres trajectoires étiologiques peuvent être pertinentes. Dans la seconde étude, l’analyse longitudinale et naturaliste des covariations humeur – interprétations se révèle d’abord féconde à identifier les phénomènes de réactivité cognitive postulés dans le modèle des interprétations. Ensuite, en conformité aux modèles intégrés de la réactivité cognitive, l’analyse des liens entre cette réactivité et les stratégies privilégiées de neutralisation des participants permet d’identifier le rôle clé des différentes stratégies de traitement de l’information dans la réactivité cognitive. / Over the past twenty years, the «appraisal model» of obsessive-compulsive disorder (OCD) (Obsessive Compulsive Cognition Working Group, 1997, 2001, 2003, and 2005) has drawn most of the empirical research on the psychological etiology and maintenance of the disorder. Nevertheless, only a few studies addressed two important postulates of the model, which is the development of beliefs associated with OCD, and the contribution of affective states to the maintenance of appraisals and beliefs (p. ex., cognitive reactivity). The current thesis aims to contribute to the empirical validation of these postulates. Based on a retrospective correlational design in a mixed (OCD and normal) sample, the first article aims to explore the links between childhood experiences (CEs) and adult OCD related beliefs. Two alternative etiological models are compared emphasizing either a rather specific association between different CEs and beliefs; or conversely, a broad non-specific association between CEs and different OCD related beliefs. Results support both the existence of specific and non-specific associations between CEs and beliefs. CEs and OCD related beliefs that showed specific links were those CEs that showed specific links to OCD related beliefs were those related to the concepts of Responsibility (R-E and OBQ-R), Threat perception (TP-E et OBQ-T), and Perfectionism (SO-E et OBQ-P). On the other hand, CEs emphasizing Threat perception (TP-E) and Sociotropy (SOC-E) related experiences also showed significant links with most OCD related beliefs (Intolerance of uncertainty [OBQ-U], Overestimation of threat [OBQ-T], Importance and Control of thoughts [OBQ-I et OBQ-C]). The aim of the second article is to assess and analyze cognitive reactivity in an OCD sample (rumination subtype) through a longitudinal naturalistic design (eight intensive single-case designs). In a first step, the contingency analysis between daily mood-states scores (4 mood-states in each participant) and daily thought appraisals (one idiosyncratically defined thought appraisal in each participant) allows for the assessment of the magnitude and rate of cognitive reactivity in each participant. On the basis of integrative models of cognitive reactivity (Affect Infusion Model, and Mood as input Hypothesis) further repeated intra-individual analyses (across subjects) and inter-individual analyses (between subjects) illustrate the critical proximal role of different processing strategies used by the participants. In summary, both studies provide results that contribute to further the validation of the appraisal model of OCD. In the first study, the identification of specific links between CEs and OCD related beliefs in adults supports the postulated etiological sequence; while the identification of non-specific links suggest that other etiological paths may be relevant In the second study, the longitudinal investigation of covariations between mood-states and appraisals of thoughts allows to reveal the expected cognitive reactivity processes. Such processes are further supported with reference to integrated models of cognitive reactivity that emphasize the critical role of different processing strategies in their expression.
659

Trombose venosa cerebral: evolução clínica e fatores prognósticos em 111 pacientes / Cererbal venous thrombosis: clinical outcome and prognostic factors in 111 patients

Dutra, Aurélio Pimenta 08 September 2008 (has links)
Introdução: A evolução clínica da trombose venosa cerebral (TVC) pode variar desde a recuperação completa ao óbito. Séries européias e um estudo multicêntrico identificaram alguns fatores indicativos de prognóstico da TVC, dado importante na decisão da melhor terapêutica para os pacientes. Este estudo busca identificar, a partir do seguimento prospectivo de cento e onze pacientes com TVC, os fatores prognósticos envolvidos na evolução clínica durante o período de 2 anos. Pacientes Métodos: Foram acompanhados prospectivamente 111 pacientes com diagnóstico de TVC desde a fase aguda do diagnóstico, confirmado por meio de RM de encéfalo e/ou angiografia cerebral (ARM, ATC ou angiografia digital). Obtidos dados do quadro clínico e seguimento por um protocolo clínico. 96% dos pacientes foram anticoagulados na fase aguda com heparina e seguida de anticoagulação com warfarina. Submetidos a investigação para os fatores predisponentes para TVC. A evolução clínica foi quantificada por meio da escala modificada de Rankin (EMR) após 3, 6, 12 e 24 meses, definindo os pacientes de bom prognóstico EMR 1, e mau prognóstico EMR 2. Comparamos dados clínicos da fase aguda e resultados encontrados nos exames de imagem e laboratoriais como possíveis fatores prognósticos, através da análise univariada pelo teste 2 e os fatores de significância estatística (p<0,1), foram analisados com regressão logística ajustada e cálculo da razão de chances (RC), (intervalo de confiança IC=95%). Resultados: A média da idade dos pacientes foi de 35 anos, 72% mulheres, 40% afro-brasileiros. As principais manifestações clínicas foram: cefaléia 97%, déficit focal 47%, crise epiléptica 40%, alteração da consciência 28%, síndrome de HIC (SHIC) isolada 40%. Quanto aos fatores predisponentes; 75% das mulheres usavam anticoncepcional, 31% dos pacientes apresentavam trombofilia hereditária, 13% SAAF, 6% eram portadores de vasculites, 25% outros estados pro trombóticos, 7 % apresentavam fatores locais (infecciosos ou MAV); e 5% das mulheres estavam no puerpério ou gestação. Os dados de neuroimagem revelaram que 42% apresentaram trombose em mais de um sistema venoso, 33% tiveram infartos hemorrágicos e 18% infartos venosos isquêmicos, e 20% dos pacientes apresentaram trombose de veias e seios profundos. Após 24 meses 18 pacientes (17%) apresentaram EMR 2 e os fatores determinantes de pior prognóstico foram: a etnia afro-brasileira p=0,001; RC= 11,37 (95% IC 2.81- 46,08), alteração do nível de consciência p=0,007; RC=4.56 (95% IC 1.61-19.45), sexo masculino p=0,049 RC=3.55 (95% IC 1.00-12.55) e idade acima de 32 anos p=0,05 RC = 3.95 (95% IC 0,97-15.20). A presença isolada de ACO como fator predisponente está associado ao melhor prognóstico p = 0,016; RC=5,17(95% IC 1.37-19.57) e após 24 meses a mortalidade foi de 4,5%. Conclusão: A análise deste trabalho evidencia que a maioria dos pacientes portadores de TVC (83%) apresenta uma evolução benigna com o tratamento, estando após 24 meses assintomáticos ou com sintomas mínimos, e a presença de ACO como fator predisponente isolado a TVC está relacionado ao melhor prognóstico. Os pacientes com pior evolução clínica têm a raça afro-brasileira, a alteração do nível de consciência, sexo masculino e idade acima de 32 anos como fatores determinantes de pior prognóstico em vinte e quatro meses. A identificação destes fatores é importante por direcionar um melhor tratamento na fase aguda da TVC para casos selecionados / Introduction: The cerebral venous thrombosis (CVT) clinical evolution is quite variable from complete recovery to death. Some European series and a multicenter study had identified prognostic factors related to CVT prognosis. The identification of these factors is important for the best therapeutic decision to patients. This study aims to identify the prognostic factors enrolled in clinical evolution of 111 patients with CVT in a prospective outcome clinical trial during two years. Subjects and Methods: One hundred and eleven patients were prospective followed with the diagnosis of CVT since acute phase diagnosis, confirmed by brain MRI and/or brain angiography (MRA , CTA or digital angiography). Information about clinical features and follow-up were filled on a clinical form. 96% of the patients were anticoagulated on heparin followed by warfarin treatment. The patients were investigated to predisposing factors to CVT. The clinical evaluation was accessed by the modified Rakin scale (mRs) after 3, 6, 12 and 24 months, considering patients with good outcome when mRs 2. The acute phase clinical features, laboratory and imaging data were compared as possible prognosis factors beyond univariate 2 test and the factors with statistical significance (p<0,1) and then analyzed by logistic regression adjusted and Odds Ratio values (confidence interval CI=95%). Results: The mean age of the patients was 35 years, 72% were women, and 40% were African Brazilian. The main clinical features observed were: headache 97%, focal sign 47%, epileptic seizure 40%, isolated ICH syndrome 40% and altered mental status 28%. All the patients were investigated to predisposing factors; 75% of the women were on oral contraceptive, 31% of the patients presented hereditary thrombophilia, 13 % antiphospholipid syndrome, 6% presented vasculitis, 25% other protrhrombotic state, 7% presented some local feature (arterialvenous malformation or infection) and 5% of women were pregnant or on puerperium. The neuroimaging data showed that 42% of the patients presented thrombosis in more than one venous system, 33% had hemorrhage infarcts, 18% ischemic venous infarcts and 20% of the patients had thrombosis of the deep venous system. After two years 17% had a mRs > 2 and the features enrolled on poor prognosis were: African Brazilian patients p=0,001; OR= 11,37 (95% IC 2.81- 46,08), altered mental status p=0,007; OR=4.56 (95% IC 1.61-19.45), male gender p=0,049 OR=3.55 (95% IC 1.00-12.55) and age over 32 years p=0,05 OR = 3.95 (95% IC 0,97- 15.20). The presence of oral contraceptives as isolated predisposing factor was related to good outcome CVT p=0,016; OR=5,17(95% IC 1.37-19.57) and after two years the mortality rate was 4,5%. Conclusion: This study data show that most patients with the diagnosis of CVT (83%) has a good outcome with the treatment, after two years follow up they have no symptoms or minimal deficits, and the presence of oral contraceptives as isolated predisposing factor was related to better outcome CVT. The patients with poor prognosis have the African Brazilian ethnic group, altered mental status, male gender and age over 32 years as the factors enrolled on bad clinical evolution in two years. The identification of these factors can have future value on treatment better choice on acute phase to selected CVT patients
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Estudos dos genes Tbx19 e Crhr1 em cães da raça poodle com hipercortisolismo ACTH-dependente / Study of Tbx19 and Crhr1 genes in Poodle dogs with ACTH-dependent hypercortisolism

Marco, Viviani de 29 April 2010 (has links)
O hipercortisolismo ACTH-dependente (HAD), também chamado de doença de Cushing, é uma das endocrinopatias mais comumente diagnosticadas na espécie canina. A sintomatologia clínica ocorre, secundariamente, aos efeitos gliconeogênicos, catabólicos, antiinflamatórios e imunossupressores dos glicocorticóides sobre vários sistemas orgânicos. Há uma marcante predisposição da doença na raça poodle e casos familiais têm sido diagnosticados sugerindo uma causa genética. As alterações moleculares que levam ao desenvolvimento do HAD em cães permanecem indefinidas. Dentre os genes implicados no desenvolvimento dos corticotrofos e na regulação do eixo corticotrófico, destacam-se o Tbx19 e o Crhr1, respectivamente. O Tbx19 é um fator de transcrição obrigatório para a transcrição do gene da proopiomelanocortina (POMC) e para a diferenciação terminal dos corticotrofos. Como está presente, exclusivamente, em corticotrofos normais e adenomatosos, foi proposto seu envolvimento na secreção excessiva de ACTH na doença de Cushing. A presença de CRHR1 nos corticotrofinomas na espécie humana e canina levantou a hipótese da sua participação na tumorigênese hipofisária, promovendo uma estimulação celular prolongada, mesmo na ausência de hormônios hipotalâmicos. Um aumento da expressão do CRHR1 foi demonstrado nos tumores corticotróficos, apesar da secreção autônoma de ACTH e dos níveis portais suprimidos de CRH em pacientes humanos e caninos com doença de Cushing. Os objetivos do presente trabalho foram pesquisar a presença de mutações germinativas nas regiões codificadoras dos genes Tbx19 e Crhr1 em cães com HAD. Para tanto, estudamos 50 cães da raça poodle com hipercortisolismo ACTH-dependente (33 fêmeas e 17 machos), com idade média de 8,71 anos e 50 cães controle da mesma raça (32 fêmeas e 18 machos) com idade superior a 6 anos (média de 9,38 anos) e sem endocrinopatias. O DNA genômico foi extraído e amplificado através da reação de polimerização em cadeia (PCR), utilizando-se oligonucleotídeos (primers) específicos para os genes Tbx19 e Crhr1. Foi identificada uma nova variante alélica tanto no Tbx19 como no Crhr1, ambas não descritas na literatura. No gene Tbx19, a variante p. S343G foi encontrada em dois cães não aparentados, mas também em dois controles normais, sugerindo tratar-se de um novo polimorfismo. Já a variante p. V97M do Crhr1 foi encontrada, em heterozigose em um animal com HAD, porém não foi observada em cem alelos normais. O códon 97 está localizado no domínio extracelular aminoterminal do gene Crhr1, de extrema importância para a ligação com alta afinidade ao ligante. O estudo molecular da estrutura quartenária da proteína mutada, seguido da avaliação da energia de ligação da superfície de contato entre o hormônio e o receptor revelou um rearranjo estrutural com alteração da superfície de contato entre o CRH e o seu receptor CRHR1, resultando em uma energia de ligação 17% superior à do receptor selvagem. Em conclusão, esse estudo não identificou alterações no gene Tbx19 associadas ao hipercortisolismo ACTH-dependente canino, mas por outro lado, identificou pela primeira vez, uma mutação ativadora no Crhr1, provavelmente responsável pelo hipercortisolismo ACTH-dependente em um cão da raça poodle. / The ACTH-dependent hypercortisolism (ADH), also called Cushing\'s disease, is one of the most commonly diagnosed endocrine diseases in dogs. The symptoms occur due to glucocorticoids excess leading to gluconeogenic, catabolic, anti-inflammatory and immunosuppressive effects in multiple organs and systems. There is a high incidence of Cushing\'s disease in Poodles and familial disease has been identified suggesting a genetic involvement. The molecular changes that lead to the development of ACTH-dependent hypercortisolism in dogs remain undefined. Among genes implicated in corticotroph development and in corticotropic axis regulation, we would like to point out Tbx19 and Crhr1, respectively. Tbx19 gene is a transcription factor required for transcription of the proopiomelanocortin gene and for terminal differentiation of the corticotroph. Inactivating mutations in that gene are associated with human isolated ACTH deficiency. Since Tbx19 is present exclusively in normal and adenomatous corticotroph cells, its involvement in the secretion of ACTH in Cushing\'s disease was proposed. The presence of CRHR1 in corticotrophinomas in humans and dogs raised the possibility of its involvement in pituitary tumorigenesis, promoting prolonged cell stimulation, even in the absence of hypothalamic hormones. An increased expression of the CRHR1 mRNA was demonstrated in human and canine ACTH-secreting pituitary adenomas, despite the autonomous ACTH secretion and the low portal levels of CRH. The aim of this study was to investigate Tbx19 and Crhr1 coding region mutations in Poodle dogs with ACTH-dependent hypercortisolism. We studied 50 Poodle dogs with ADH (33 females and 17 males) with a mean age of 8.71 years and 50 control dogs of the same breed (32 females and 18 males) older than 6 years (mean 9.38 years) and without endocrinopathies. Genomic DNA was extracted from peripheral blood, amplified by the polymerase chain reaction (PCR) using specific intronic primers and submitted to automatic sequence. We identified a new allelic variant in the Tbx19 and Crhr1 coding regions. The allelic variant p. S343G in the Tbx19 gene was found in two unrelated dogs, but also in two normal controls, suggesting that this is a new polymorphism. The Crhr1 allelic variant p. V97M was found in heterozygosity in one animal with ACTH-dependent hypercortisolism, but was not observed in one hundred normal alleles. The codon 97 is located in the extracellular amino terminal domain of the Crhr1 and is extremely important for high affinity ligand binding. The molecular analysis of the quaternary structure of normal and mutated proteins, followed by evaluation of the binding energy of the contact surface between the hormone and the receptor showed a structural rearrangement of the mutated protein by changing the contact surface between the CRH and its receptor CRHR1, resulting in a binding energy 17% higher than the wild type. In conclusion, this study did not identify Tbx19 mutations associated with canine ACTH-dependent hypercortisolism, but on the other hand, we first identified a Crhr1 gain-of-function mutation probably responsible for ACTH-dependent hypercortisolism in a Poodle dog of our cohort.

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