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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.
251

Exploratory Factor Analysis of the Geriatric Depression Scale Among Cardiac Patients

Hupp, Gregory S. 05 1900 (has links)
The Geriatric Depression Scale (GDS) was originally designed as a measure for screening depression among elderly medical patients. Although this instrument is well validated among a general medical population, it has never been evaluated with specific regard to cardiac patients, the largest single group of medical patients over 40 years of age. A general cardiac sample of 655 patients completed the GDS within 10 weeks of the cardiac event. Exploratory factor analyses were conducted on the main sample, then on several subgroups of participants with regard to diagnostic category, gender, and age. The GDS generally produces factor structures with several symptom domains with a high rate of total variance. The myocardial infarction group endorsed general symptoms of depression whereas the coronary artery bypass graft group reported greater levels of despair regarding their condition. Overall, males primarily reported agitation and hopelessness while females reported symptoms of depressed mood.
252

Ošetřovatelská péče o pacienta po operaci chlopenních vad / Nursing Care for Patient after Surgery of Valvular Defects

Beranová, Veronika January 2015 (has links)
This thesis is focused on the nursing care for patient after valvular defects surgery. The aim of this final paper is to ascertain the principles of specialized nursing care for patient after valvular defects surgery, analyse the condition of written standards for providing aftercare to patients who underwent valvular defects surgery, or the state of the nursing protocols in specialized nursing care. The purpose of qualitative - observational research in providing specialized nursing care is to find an answer to the question of whether the specifics of nursing care in Prague cardiac centres are significantly different. The theoretical section contains chapters describing cardiac centres, the history of surgical treatment of heart valves, and the most common valvular heart defects in adulthood. In the theoretical section of this study, I focus in detail on the nursing care for patients following cardiac procedure, ensuring not to forget the monitoring of physiological functions, artificial pulmonary ventilation, and immediate position after elective cardiac surgery. The empirical section is divided into quantitative and qualitative research. The quantitative empirical investigation is focused on an anonymous questionary survey that has been applied in three Prague cardiac centres. Approximately 150...
253

Lifestyle behaviours, psychological wellbeing and cardiovascular disease in women executives and senior management

Crowhurst, Rhiannon January 2016 (has links)
A dissertation submitted in partial fulfilment of the requirements for the degree of Bachelor of Arts Masters (Industrial/ Organisational Psychology) in the Faculty of Humanities, University of the Witwatersrand, Johannesburg. March, 2016 / This study investigated whether the lifestyle behaviours and psychological well-being of women executives and managers predicted their ten-year risk of developing cardiovascular disease. The sample of South African women executives and managers work in a variety of industries in the cities of Johannesburg, Durban and Cape Town. The study sought to determine the predictability of the women executives and managers’ risk of developing cardiovascular disease through examining their level of alcohol consumption, level of physical exercise and the nutritional and dietary choices that they made as well as their level of depression, anxiety and stress. The data was gathered through an executive health and wellness programme and logistic regression and Chi-squared tests of association were used in conducting the analyses. The results suggested that the level of alcohol consumption and the nutritional and dietary choices made were predictive of the individual’s ten-year risk of developing cardiovascular disease. Additionally, the level of anxiety was found to be associated with the risk of developing cardiovascular disease. The results suggest that both individuals and organisations should prioritise the changing of unhealthy lifestyle behaviours, specifically excessive alcohol consumption and daily dietary choices, in order to lower their risk of developing cardiovascular disease. / MT2017
254

Perioperative Antibiotikaprophylaxe bei angeborenen Herzfehlern

Boschnakow, Anett 19 April 2002 (has links)
In den letzten Jahren haben sich die Empfehlungen für eine Antibiotikaprophylaxe in der Herzchirurgie bezüglich Antibiotikawahl und Applikationsdauer verändert und gehen nicht speziell auf die Kinderherzchirurgie ein. Im Deutschen Herzzentrum Berlin wurde seit 1988 bei Operationen aufgrund angeborener Herzfehler die Kombinationsprophylaxe mit Piperacillin und Cefotaxim angewandt. Neue internationale Empfehlungen schlagen jedoch ein Cephalosporin der I. oder II. Generation vor. Fragestellung dieser prospektiven Beobachtungsstudie ist deshalb, ob eine Umstellung der im DHZB üblichen Kombinationsprophylaxe auf eine Monoprophylaxe mit Cefotiam gerechtfertigt ist. Vom 1.3. - 31.8. 1995 wurden 180 Patienten mit Operationen am offenen Herzen in die Studie eingeschlossen. 99 Patienten erhielten die bisher im DHZB etablierte Kombinationsprophylaxe mit Cefotaxim und Piperacillin (Cx/P-Gruppe). 81 Patienten bekamen eine Monoprophylaxe mit Cefotiam (Ct-Gruppe). Die postoperative Infektionsrate betrug in der Ct-Gruppe 14,8 % und in der Cx/P-Gruppe 17,2 %. Die Prophylaxe erfolgte für beide Gruppen durchschnittlich 103 Stunden bzw. 110 Stunden. Die Studie konnte aufgrund geringer Patientenanzahl aus statistischer Sicht keinen Beweis für einen Unterschied erbringen. Dafür zeigte die Metaanalyse, daß auch bei einer großen Patientenanzahl (n=4177) kein statistischer Unterschied zwischen einer Schmalspektrum- und einer Breitspektrumprophylaxe besteht. Es wurde ferner gezeigt, daß Cefotiam den Anforderungen einer effektiven Prophylaxe gerecht wird und Vorteile gegenüber der Kombinationsprophylaxe aufweist. Die Studie hat dazu beigetragen, daß seit 1996 in der Kinderherzchirurgie im DHZB eine Monoprophylaxe mit einem Cephalosporin der I. Generation - Cefazolin - durchgeführt wird und hat weiterhin eine Verkürzung der Prophylaxedauer bewirkt. / Perioperative antibiotic prophylaxis for patients with congenital heart diseases Recommendations for antimicrobial prophylaxis regarding the choice of antibiotics and the application time have changed and do not include cardiac surgery for infants. A combination of piperacillin and cefotaxim has been used since 1988 in the German Heart Institute of Berlin. Updated recommendation now propose the use of a I. or II. generation cephalosporin. The purpose of this prospective study was to evaluate whether a change from the so long used combined prophylaxis towards a monoprophylaxis with cefotiam is justified. From 1st of March until 31st of August 1995 a total number of 180 patients with an open heart surgery were included into the study. 99 patients received a combination with cefotaxim and piperacillin (cx/p-group), which was the standard combination in the German Heart Institute of Berlin. 81 patients received a monoprophylaxis with cefotiam (ct-group). The postoperative rate of infections was 14,8 % in the ct-group and 17,2 % in the cx/p-group. For both groups the duration of prophylaxis was on average 103 respectively 110 hours. Due to a relatively small number of patients the study could not show a statistically significant difference between both prophylactic regimes. The performed meta-analysis comparing the postoperative infections in small spectrum and broad spectrum prophylaxis in the open heart surgery did not find a significant difference in a large group of patients (n=4177). Our study supports the fact, that cefotiam meets the criteria of an effective antibiotic prophylaxis and has additional benefits compared to the combined prophylaxis scheme. The results of this study have led to a replacement of the old perioperative prophylaxis regime by cefotiam for open heart surgery for infants in the German Heart Institute of Berlin since 1996 and have led to a reduction of the application time during the prophylaxis.
255

Análise ecocardiográfica evolutiva tardia da função ventricular direita no pós-operatório da tetralogia de Fallot: associação com alterações histopatológicas preexistentes do miocádio / Late evolutive echocardiographic analysis of the right ventricular function in the postoperative of tetralogy of Fallot: association with preexistent histopathological changes in the myocardium

Grau, Claudia Regina Pinheiro de Castro 11 April 2018 (has links)
Introdução: Previamente, demonstramos que o remodelamento histológico do miocárdio à época da correção da tetralogia de Fallot (TF) influenciou na função do ventrículo direito (VD) no pós-operatório (PO) precoce. O impacto da fibrose miocárdica na função ventricular no PO tardio ainda é desconhecido. O objetivo deste estudo foi avaliar ecocardiograficamente na mesma coorte de pacientes a função do VD no PO tardio, comparando com dados anteriormente obtidos por ecocardiografia convencional e morfometria miocárdica. Métodos: Estudamos 20 pacientes no PO da TF (tempo de seguimento = 96,6 ± 13,3 meses), 15 homens (75%), idade média no PO tardio (PO2) 128,3 ± 25,7 meses. As velocidades miocárdicas do VD diastólica precoce (e´), tardia (a\') e sistólica (S\') foram avaliadas pelo Doppler tecidual no pré-operatório, três dias após a cirurgia, entre 30º-90º dia e no PO2. Parâmetros convencionais, como a excursão sistólica do anel da valva tricúspide (TAPSE), variação fracional da área (FAC), volume do átrio direito indexado, pico da velocidade de enchimento diastólico precoce (E) do fluxo transvalvar tricúspide e da deformação miocárdica global e regional, strain longitudinal sistólico (GLS), strain rate sistólico (GLSRs) e o strain no pico do tempo de relaxamento isovolumétrico (GLSTRIV), foram analisados apenas no PO2. Também, nesta fase, realizamos a análise tridimensional da fração de ejeção, e dos volumes diastólico e sistólico finais do VD. Resultados: A velocidade a\' diminuiu nas avaliações iniciais e persistiu anormal no PO2 (RM ANOVA p < 0,001). Houve correlação negativa significante entre a velocidade e\' no PO2 e a fração de área de fibrose miocárdica (FIBR) (p = 0,02; r = -0,54), e correlação positiva entre FIBR e a relação E/e\' (p= 0,0002; r= 0,787). No PO2, o TAPSE (1,50 ± 0,19cm) foi reduzido e FAC normal (47,51± 7,56%). O valor do GLS global foi 18,48 ± 2,97%, com Z score < -2 em 16 pacientes e diferiu regionalmente no segmento médio do septo (Z score < -2 em 5 pacientes) e no segmento médio da parede lateral (Z score < -2 em 1 paciente). Houve correlação negativa entre FIBR e GLS no segmento médio septal (p = 0,0376; r = -0,493), entretanto sem influência no GLS global. No PO2, a insuficiência pulmonar residual foi moderada ou acentuada em 15 pac (75%), sem diferença quanto à FIBR miocárdica em relação ao grau leve (p = 0,58). Estavam aumentados os volumes indexados: diastólico final médio (89,5 ± 34,3ml/m²; Z score > 2DP em 12 pacientes) e sistólico (40,6 ± 9,1ml/m²; Z score > 2DP em 14 pacientes). A fração de ejeção média foi normal 51,8 ± 6,9% e não houve correlação com a FIBR. Conclusões: A avaliação ecocardiográfica tardia identificou alterações evolutivas e adaptativas das funções sistólica e diastólica do VD, com função sistólica preservada e função diastólica anormal e associada ao grau de FIBR avaliado em amostras operatórias; o estudo da deformação miocárdica revelou alterações globais e regionais, possivelmente relacionadas à arquitetura do miocárdio nessa malformação e às adaptações decorrentes da interposição de retalhos e suturas cirúrgicas; a avaliação pelo modo tridimensional correlacionou-se positivamente com as medidas obtidas no modo bidimensional; a insuficiência pulmonar foi lesão residual altamente prevalente / Introduction: We have previously demonstrated that the myocardial remodeling at the time of corrective surgery in tetralogy of Fallot (TF) patients influenced the right ventricular (RV) function in the early post-operative period (PO). The impact of myocardial fibrosis in late follow up (LFU) has not been investigated so far. Our objective was to analyze in the same cohort of patients in LFU, the RV function, comparing the obtained results with echocardiographic data from the early PO and with myocardial morphometry. Methods: 20 patients in the late FLU of TF correction were studied (time of follow up = 96.6 ± 13.3 months), 15 men (75%), mean age at LFU 128.3 ± 25.7months. The early (e\') and late (a\') diastolic and the systolic (S\') myocardial velocities were evaluated through tissue Doppler in the pre-operative period, three days after surgery, between the 30o-90o days and in LFU. We analyzed conventional echocardiographic parameters like the tricuspid annular plane systolic excursion (TAPSE), the fractional area change (FAC), the indexed right atrial volume, the peak early diastolic filling velocity (E) and of myocardial deformation: global longitudinal strain (GLS), global longitudinal systolic strain rate (GLSRs) and global longitudinal strain at the peak of the isovolumetric relaxation time (GLSTRIV) in the LFU. Also in LFU we analyzed by tridimensional echocardiography the ejection fraction and the final RV diastolic and systolic volumes. Results: The a\' velocity decreased in the initial evaluations and persisted abnormal in LFU (RM ANOVA, p < 0.001). There was a significant and negative correlation between e\' in LFU and the area fraction of myocardial fibrosis (FIBR) (p = 0.02; r = -0.54) and a positive correlation between FIBR and E/e\' ratio (p = 0.0002; r = 0.787). In the LFU TAPSE decreased (1.50 ± 0,19cm) and FAC was normal (47.51 ± 7.56%). The GLS value was 18.48 ± 2.97%, with Z score <- 2 SD in 16 patients, and was significantly different in the mid ventricular septum (Z score <- 2 in 5 patients) and in the mid segment of the lateral wall (Z score < -2 in 1 patient). There was a negative correlation between FIBR and GLS in the mid ventricular segment of the septum (p = 0.0376; r = -0.493), however without influence in GLS. In LFU pulmonary regurgitation was considered moderate or severe in 15 patients (75%), with no difference relative to the group with mild regurgitation regarding FIBR (p = 0.58). The final indexed RV volumes were increased: diastolic (89.5 ± 34.3ml/m2; Z score > 2SD in 12 patients) and systolic (40.6 ± 9.1ml/m2; Z score > 2SD in 14 patients). The mean RV ejection fraction was normal (51.8 ± 6.9%), and did not correlate with FIBR. Conclusions: The LFU echocardiographic evaluation identified evolutive and adaptative alterations in RV function, with preserved systolic and abnormal diastolic function, associated with the degree of FIBR assessed in myocardial samples; the study of myocardial deformation indexes revealed regional and global alterations, possibly related to the abnormal myocardial architecture specific for the cardiac malformation and/or to post-surgical adaptation to patches and sutures; the tridimensional echocardiography data correlated positively with those obtained through bidimensional echo; pulmonary regurgitation was a highly prevalent residual lesion
256

Gene expression profiles in neonatal heart development and functional roles of calcyclin binding protein/Siah-interacting protein in terminal differentiation of cardiomyocytes. / CUHK electronic theses & dissertations collection

January 2004 (has links)
by Au Ka Wing. / "June 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 153-162). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
257

Cardiovascular and chronic kidney disease in Chinese type 2 diabetic patients: from prognosis to management. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Conclusions. The growing epidemic of type 2 diabetes and its cardiorenal complications place a major burden on our health care system. Diabetic kidney disease is of particular importance in Asian populations including Chinese. In this series of studies, using a large prospective cohort established since 1995, I confirmed the powerful predictive value of albuminuria on cardio-renal complications. Inhibition of the RAAS interacted with both modifiable and genetic factors, notably the ACE I/D polymorphism, on the development of cardio-renal complications. In addition, it was found that CKD predicts CVD independent of albuminuria. Based on two prospective studies, I confirmed the effectiveness of global risk-factor control using structured care protocol to prevent these devastating complications. (Abstract shortened by UMI.) / I then examined the possible independent and interactive effects of CKD and albuminuria on cardio-renal outcomes in the original cohort of 5,004 patients. Glomerular filtration rate was estimated (eGFR) by the Modification of Diet in Renal Disease equation. The frequency of CKD as defined by eGFR &lt;60ml/min/1.73m 2 was 15.8% in the cohort at baseline, when 6% of patients had serum creatinine &ge;150mumol/L. / In collaboration with colleagues, I have conducted a series of studies to examine the prognostic factors for cardio-renal complications in Chinese type 2 diabetic patients. The modulating effects of RAAS inhibition and the effectiveness of rnuitidisciplinary care to prevent ESRD are also examined. / Research Hypotheses. (1) Albuminuria is a prognostic factor on cardio-renal outcomes in type 2 diabetes patients; (2) Chronic Kidney Disease is associated with other metabolic risk factors and phenotypes and is a prognostic factor on cardio-renal outcomes in type 2 diabetes patients; (3) Angiotensin-converting-enzyme insertion/deletion polymorphism is a prognostic factor on cardio-renal outcomes in type 2 diabetes patients, and has an effect on treatment responses with RAAS blockage with ACE inhibitors; (4) Structured care models by risk stratification using various prognostic factors and adherence to care protocol can improve cardio-renal outcome in type 2 diabetes patients. / Results. In a prospective cohort of 5,004 patients, I examined the effect of albuminuria and ACE inhibition on survival and cardio-renal outcomes in 3,773 patients who had been observed for at least 6 months with a mean follow up period of 35.8 months. / Taken together, measurement of serum creatinine alone without GFR estimation may underestimate the frequency of CKD in Chinese type 2 diabetic patients. Estimated GFR was inversely associated wit-29h an increasing frequency of micro- and macrovascular complications cross-sectionally and an increased risk of all-cause mortality prospectively, independent of albuminuria and metabolic control. / So Wing Yee. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3422. / Thesis (M.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 203-243). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / School code: 1307.
258

Avaliação dos motivos de referenciamento ao ambulatório de cardiologia pediátrica da Policlínica Municipal de Sorocaba pela atenção primária: criação de proposta de interação educacional em serviço

Guevara, Virna Maria 29 October 2014 (has links)
Made available in DSpace on 2016-04-27T13:10:25Z (GMT). No. of bitstreams: 1 Virna Maria Guevara.pdf: 2274504 bytes, checksum: f4a163e1284fcda1b344b0644f21a061 (MD5) Previous issue date: 2014-10-29 / Introduction- The prevalence of congenital cardiovascular disease is of 7 to 10 children in every 1000 live births. The reasons that lead to the referral of a child by primary care physicians are very varied, with cardiac heart murmur being the most common. Amongst other reasons one can find precordial pain, arrhythmia, fatigue, dyspnea, cyanosis, abnormal chest x-ray, abnormal electrocardiogram, medical examination for physical exercise. The present challenge for pediatricians, family physicians and pediatric cardiologists is to develop accurate diagnosis strategies in a cost-effective manner, with the aim of improving the treatment and save resources. Objectives- The objective is to strengthen the network of health care in its primary and secondary levels using cases of Pediatric Cardiology as the strategic condition and develop an interdisciplinary work proposal with the support of a matrix, which optimize the referral system. Material and methods- It is about the exploratory study with descriptive documental analysis from 433 referral letters of patients seen at the Pediatric Cardiology Ambulatory of Policlinic of Sorocaba from January to June 2012, along with the study of the patients medical records. The data collected is quantified using descriptive statistics when relevant. Results- One hundred and sixty-six patients (38,3%) were discharged, 93 with feedback letter of referral (56,0%). Ninetysix (22,2%) missing follow up, 9 of which had confirmed cardiovascular disease, 29 with absence of cardiovascular disease and 58 without a definitive diagnosis of cardiovascular disease. One hundred and seventy-one patients (39,5%) attend follow-ups. Conclusion- With the aim of strengthening the network of health care using recent medical advances, such as telemedicine and the concept of matrix support, as means of exchange, improvement and to save resources and knowledge / Introdução - A prevalência das cardiopatias congênitas está entre sete a dez crianças por 1000 nascidas vivas. Os motivos que levam o médico da atenção primária a encaminhar uma criança ao cardiologista pediátrico são bastante variados, sendo o sopro cardíaco a causa mais frequente. Dentre outros motivos frequentes encontram-se dor precordial, arritmias, cansaço, dispneia, cianose, radiografia de tórax anormal, eletrocardiograma alterado, avaliação para atividade física. O desafio atual dos pediatras, médicos de família e cardiopediatras é desenvolver estratégias de diagnósticos precisos e financeiramente adequados, com o intuito de melhorar o tratamento e racionalizar os recursos. Objetivos - O objetivo é fortalecer a rede de atenção à saúde em seus níveis primário e secundário, utilizando-se dos casos de Cardiologia Pediátrica como condição estratégica e desenvolver uma proposta de trabalho interdisciplinar e de interação com apoio matricial, otimizando o sistema de referência e contrarreferência. Material e método - Trata-se de estudo exploratório com análise documental descritiva das 433 guias de referenciamento de pacientes atendidos no ambulatório de Cardiologia Pediátrica da Policlínica Municipal de Sorocaba, no período de janeiro a junho de 2012, acompanhado do estudo dos prontuários. Os dados obtidos foram quantificados e utilizada a estatística descritiva quando pertinente. Resultados - Cento e sessenta e seis pacientes (38,3%) tiveram alta, 93 com contrarreferência (56,0%) preenchida. Noventa e seis pacientes (22,2%) perderam o seguimento, sendo nove com doença cardiovascular presente, 29 com doença cardiovascular ausente e 58 sem diagnóstico definitivo de doença cardiovascular. Cento e setenta e um pacientes (39,5%) pacientes mantêm seguimento. Conclusão A fim de se fortalecer a rede de atenção à saúde, a utilização de recentes avanços, como a telemedicina e o conceito de apoio matricial se colocam como meios de troca, otimização e racionalização do conhecimento e dos recursos
259

Administra??o de esteroide anab?lico durante a adolesc?ncia: avalia??o ex vivo da susceptibilidade ? inj?ria de isquemia/reperfus?o card?aca em ratos wistar adultos / Anabolic steroid administration during adolescence: ex vivo evaluation of susceptibility to cardiac ischemia / reperfusion injury in adult wistar rats

Seara, Fernando de Azevedo Cruz 24 July 2015 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-03-26T14:34:13Z No. of bitstreams: 1 2015 - Fernando de Azevedo da Cruz Seara.pdf: 1716878 bytes, checksum: 6a6ea74b23b441a8aafb15e937dea036 (MD5) / Made available in DSpace on 2018-03-26T14:34:14Z (GMT). No. of bitstreams: 1 2015 - Fernando de Azevedo da Cruz Seara.pdf: 1716878 bytes, checksum: 6a6ea74b23b441a8aafb15e937dea036 (MD5) Previous issue date: 2015-07-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / According to World Health Organization, ischemia heart diseases are the leading cause of death worldwide. Among therapeutic approaches, reperfusion is the most effective and indicated is reperfusion. Despite the better post-infarction prognostic, absolute improvement on cardiac function is hardly achieved due to ischemia/reperfusion injury (IRI). Within this context, anabolic steroids (AS) administration, in adult Wistar rats, significantly increase IRI susceptibility. Moreover, chronic administration of AS, during adolescent phase, induces persistent cardiovascular dysfunctions along adulthood. Therefore, the aim of the present study was to analyze the effects of chronic administration of supraphysiologic doses of testosterone propionate, during adolescent phase, in the susceptibility to ischemia/reperfusion injury, in adult Wistar rats. To perform it, 24 Wistar rats were allocated into two groups, AS (Testosterone propionate 5 mg kg-1, since 26? day postnatal, 5 days per week, during 5 weeks) and Control (Vehicle). In the 82? postnatal, rats were euthanized and hearts, livers, lungs, kidneys and testicles were collected. Isolated hearts were artificially perfused with modified Krebs-Henseleit solution, through Langendorff apparatus, and, then, submitted to ex vivo ischemia ? reperfusion protocol (20 minutes of stabilization, 30 minutes of global ischemia and 60 minutes of reperfusion). The left ventricle (LV) end diastolic- LVEDP), systolic- (LVSP) and developed pressures (LVDP), as well as first derivatives of pressure, maximum and minimum (dP/dt, maximum and minimum, respectively) were measured through an intraventricular latex balloon, connected to a pressure transducer. Through the electrocardiogram, susceptibility to arrhythmic episodes was analyzed. At the end of the protocol, area of infarct was delimited and gene expression of ? and ? myosin heavy chains and Glyceraldehyde 3-phosphate dehydrogenase, as well as the activity of nicotinamide adenine dinucleotide phosphate-oxidase (Nox) enzymes, were calculated. In comparison to Control group, hearts from AS group presented: Hypertrophy, due to an increase in cardiac mass (33%, P<0,001) and index (37%, P<0,001); Significantly increase in the area of infarct (54,76%, P<0,05); Worst recovery of both LVEDP and LVDP, along reperfusion; Less recovery of maximum dP/dt, during reperfusion, despite the equivalent LVSP; Reduced basal minimum dP/dt and, subsequently, reduction in the recovery of the aforementioned parameter, regarding reperfusion period; Enhanced gene expression of MHC? (%), consistent with the loss of mechanical performance; Increased incidence of arrhythmic episodes in the reperfusion period (100%, P<0,01). No statistical difference could be seen in regard to the Nox activity. For the first time, we demonstrated that AS treatment during adolescent phase promotes cardiac hypertrophy and gene reprogramming, both persistent during adulthood, besides an increase susceptibility to IRI, through in the larger area of infarct and poor recovery of cardiac electrical and mechanical proprieties, in isolated hearts of adult Wistar rats / De acordo com a OMS, as doen?as isqu?micas do cora??o consistem na maior causa mortis global. Dentre as abordagens terap?uticas, a mais eficaz ? a reperfus?o. A despeito da melhora no progn?stico p?s-infarto, a recupera??o plena da fun??o card?aca dificilmente ? alcan?ada, devido a inj?ria de isquemia/reperfus?o (IIR). Neste contexto, a administra??o de EA em ratos Wistar adultos enaltece a susceptibilidade ? IIR. Ademais, a administra??o de EA em ratos Wistar, ao longo da adolesc?ncia, favorece o desenvolvimento de disfun??es cardiovasculares persistentes durante a fase adulta. Desta forma, objetivou-se, com o presente estudo, analisar os efeitos da sobrecarga cr?nica de propionato de testosterona, ao longo da fase adolescente, na susceptibilidade ? IIR, em ratos Wistar adultos. Para tanto, foram utilizados 24 ratos Wistar machos, divididos em dois grupos: EA (Propionato de testosterona 5 mg kg-1, a partir do 26? dia p?s-natal, 5 vezes por semana/ 5 semanas) e CTL (ve?culo). No 82? dia p?s-natal, os ratos foram submetidos ? eutan?sia para a coleta ?rg?os. Os cora??es isolados foram submetidos ? perfus?o artificial em aparato de Langendorff, e, assim, ao protocolo de isquemia/reperfus?o. As press?es diast?lica final (PDF), sist?lica (PS) e desenvolvida (PD), do ventr?culo esquerdo (VE), e as primeiras derivadas de press?o do VE, m?xima e m?nima (dP/dt m?xima e m?nima, respectivamente), foram mensuradas atrav?s de um bal?o de l?tex intraventricular, conectado a um transdutor de press?o. Atrav?s do eletrocardiograma, foi analisada a susceptibilidade aos epis?dios arr?tmicos. Ao final do protocolo, as ?reas de infarto foram demarcadas e a express?o g?nica das cadeias pesadas de miosina e gliceralde?do-3-fosfato desidrogenase, assim como a atividade enzimas da fam?lia de niconinam?da adenina dinucleot?deo fosfato oxidase (Nox), no ventr?culo esquerdo, foram avaliadas. Em rela??o ao grupo Controle, os cora??es dos animais tratados com EA apresentaram: Hipertrofia, atrav?s do aumento na massa (aumento de 33%, P<0,001) e do ?ndice card?aco (aumento de 37%, P<0,001); aumento significativo da ?rea de infarto (aumento de 54,76%, P<0,05); T?nue recupera??o da PDFVE, assim como da PDVE, durante a reperfus?o; Inferior recupera??o da dP/dt m?xima, ao longo da reperfus?o, a despeito da equivalente recupera??o na PSVE; Reduzida dP/dt m?nima basal e, subsequentemente, redu??o na recupera??o deste par?metro, ao longo da reperfus?o; Aumento significativo da express?o g?nica da MHC? (P<0,01), condizente o preju?zo no desempenho mec?nico; Maior incid?ncia de epis?dios arr?tmicos, ao longo da reperfus?o (aumento de 100%, P<0,01). N?o houve diferen?a em rela??o ?s atividades das Nox. Pela primeira vez, foi demonstrado que a administra??o de EA, ao longo da adolesc?ncia, provoca hipertrofia e reprograma??o g?nica card?aca, persistente durante a fase adulta, al?m de aumentar, significativamente, a susceptibilidade ? IIR, por meio do aumento na ?rea de infarto e piora na recupera??o das propriedades mec?nicas e el?tricas card?acas, em cora??es isolados de ratos Wistar adultos.
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Multiple-imputation approaches to haplotypic analysis of population-based data with applications to cardiovascular disease

McCaskie, Pamela Ann January 2008 (has links)
[Truncated abstract] This thesis investigates novel methods for the genetic association analysis of haplotype data in samples of unrelated individuals, and applies these methods to the analysis of coronary heart disease and related phenotypes. Determining the inheritance pattern of genetic variants in studies of unrelated individuals can be problematic because family members of the studied individuals are often not available. For the analysis of individual genetic loci, no problem arises because the unit of interest is the observed genotype. When the unit of interest is the linear combination of alleles along one chromosome, inherited together in a haplotype, it is not always possible to determine with certainty the inheritance pattern, and therefore statistical methods to infer these patterns must be adopted. Due to genotypic heterozygosity, mutliple possible haplotype configurations can often resolve an individual's genotype measures at multiple loci. When haplotypes are not known, but are inferred statistically, an element of uncertainty is thus inherent which, if not dealt with appropriately, can result in unreliable estimates of effect sizes in an association setting. The core aim of the research described in this thesis was to develop and implement a general method for haplotype-based association analysis using multiple imputation to appropriately deal with uncertainty haplotype assignment. Regression-based approaches to association analysis provide flexible methods to investigate the influence of a covariate on a response variable, adjusting for the effects of other variables including interaction terms. ... These methods are then applied to models accommodating binary, quantitative, longitudinal and survival data. The performance of the multiple imputation method implemented was assessed using simulated data under a range of haplotypic effect sizes and genetic inheritance patterns. The multiple imputation approach performed better, on average, than ignoring haplotypic uncertainty, and provided estimates that in most cases were similar to those observed when haplotypes were known. The haplotype association methods developed in this thesis were used to investigate the genetic epidemiology of cardiovascular disease, utilising data for the cholesteryl ester transfer protein gene (CETP), the hepatic lipase (LIPC) gene and the 15- lipoxygenase (ALOX15) gene on a total of 6,487 individuals from three Western Australian studies. Results of these analyses suggested single nucleotide polymorphisms (SNPs) and haplotypes in the CETP gene were associated with increased plasma high-density lipoprotein cholesterol (HDL-C). SNPs in the LIPC gene were also associated with increased HDL-C and haplotypes in the ALOX15 gene were associated with risk of carotid plaque among individuals with premature CHD. The research presented in this thesis is both novel and important as it provides methods for the analysis of haplotypic associations with a range of response types, while incorporating information about haplotype uncertainty inherent in populationbased studies. These methods are shown to perform well for a range of simulated and real data situations, and have been written into a statistical analysis package that has been freely released to the research community.

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