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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.
661

Predictors of left ventricular hypertrophy, diastolic dysfunction and atrial fibrillation:the roles of adiponectin, ambulatory blood pressure and dietary sodium intake

Pääkkö, T. (Tero) 27 November 2018 (has links)
Abstract Left ventricular hypertrophy (LVH), a common complication of elevated blood pressure (BP), is a risk factor for cardiovascular (CV) morbidity and mortality. Adiponectin has been shown to have cardioprotective effects and is inversely associated with LVH. BP can be measured at a clinical visit, as a momentary value. Ambulatory blood pressure (APB) measurement (ABPM) is a method of repeated BP measurements through a defined period, targeted to evaluate the circadian BP profile. High BP and ABPM have been shown to be associated with LVH and left ventricular diastolic dysfunction (LVDD). A high sodium intake has been associated with elevated BP and adverse CV outcome. The aim of this study was to investigate the associations between adiponectin and left ventricular mass index (LVMI), a measure of LVH, ABPM and the development of LVDD during long-term follow-up, ABPM and the change in LVMI during long-term follow-up, and the role of dietary sodium intake in the incidence of AF. Adiponectin has been shown to have vasoprotective, anti-inflammatory and cardioprotective effects. Hypoadiponectinemia has been associated with hypertension, coronary artery disease (CAD) and LVH. In this study, adiponectin levels were inversely associated with LVMI, even after adjustment with conventional risk factors of LVH, in a fairly large sample of middle-aged subjects. Elevated BP and pulse pressure (PP) have been associated with echocardiographic measures of LVDD. In this study, the association between APBM and the development of LVDD during a 20-year follow-up was evaluated. Ambulatory PP (APP) was shown to independently associate with the development of LVDD, even after adjustment with conventional risk factors of LVDD. APBM has been associated with LVH in cross-sectional assessments and has also been shown to have predictive value in future LVMI or LVH. In a few studies the predictive value of APP in future LVMI was observed. In the present study, an increase in APP was shown to predict the change in LVMI during long-term follow-up. In this study, the association between dietary sodium intake and the incidence of AF was evaluated. A high sodium intake predicted the occurrence of AF, which is a novel finding. In conclusion, this study offers novel findings about predictive factors in the entity of cardiac remodelling. / Tiivistelmä Vasemman kammion hypertrofia on yleinen kohonneen verenpaineen seuraus ja sen on todettu olevan sydän- ja verisuonitapahtumien riskitekijä. Adiponektiinin on osoitettu suojaavan vasemman kammion hypertrofialta. Ambulatorinen verenpaineen mittaus on menetelmä, jossa verenpaine mitataan määritellyllä ajanjaksolla toistuvasti, mikä antaa kuvan verenpaineesta vuorokauden eri jaksoissa. Kohonneella ambulatorisella verenpaineella on osoitettu olevan yhteys vasemman kammion hypertrofiaan sekä vasemman kammion diastoliseen vajaatoimintaan. Runsas natriumin saanti on yhteydessä kohonneeseen verenpaineeseen sekä sydän- ja verisuonisairauksiin. Tämän tutkimuksen tarkoituksena on selvittää yhteyksiä adiponektiinin ja vasemman kammion massaindeksin välillä, ambulatorisen verenpaineen ja vasemman kammion diastolisen vajaatoiminnan kehittymisen välillä, ambulatorisen verenpaineen ja vasemman kammion massaindeksin muutoksen välillä sekä natriumin saannin ja eteisvärinän ilmaantuvuuden välillä. Adiponektiinilla on todettu olevan suotuisia vaikutuksia verisuonistoon, tulehdusreaktion hillintään sekä sydänlihakseen. Matalan adiponektiinitason on osoitettu olevan yhteydessä verenpainetautiin, sepelvaltimotautiin sekä vasemman kammion hypertrofiaan. Tässä tutkimuksessa adiponektiinihormonilla osoitettiin olevan käänteinen yhteys vasemman kammion massaindeksiin, vaikka perinteiset riskitekijät otettiin huomioon. Kohonneella verenpaineella sekä pulssipaineella on osoitettu olevan yhteys vasemman kammion diastoliseen vajaatoimintaan. Tässä tutkimuksessa arvioitiin ambulatorisen verenpaineen merkitystä vasemman kammion diastolisen vajaatoiminnan kehittymisessä. Ambulatorinen pulssipaine osoittautui riskitekijäksi, vaikka perinteiset riskitekijät otettiin huomioon. Ambulatorisella verenpaineella ja pulssipaineella on osoitettu olevan yhteys vasemman kammion hypertrofiaan poikkileikkaustutkimuksissa ja seurantatutkimuksissa. Tässä tutkimuksessa ambulatorisen pulssipaineen nousun havaittiin ennustavan vasemman kammion massaindeksin kasvua pitkäaikaisseurannassa. Tässä tutkimuksessa korkean natriumin saannin todettiin olevan yhteydessä lisääntyneeseen eteisvärinän ilmaantuvuuteen. Tätä yhteyttä ei ole aiemmin todettu muissa tutkimuksissa. Tässä tutkimuksessa löydettiin uusia riskitekijöitä sydämen patologisiin ilmentymiin liittyen.
662

Avaliação da função sistólica biventricular pelo speckle tracking em pacientes com anemia falciforme / Evaluation of biventricular systolic function by speckle tracking in patients with homozygous sickle cell anemia

João Carlos Moron Saes Braga 28 July 2014 (has links)
Introdução: A doença falciforme (DF) é a afecção hematológica hereditária de maior prevalência no mundo, sendo que a anemia falciforme (AF) é a forma mais grave com elevada morbidade e mortalidade. Alterações cardíacas são reconhecidamente associadas à AF, como aumento cavitário, hipertensão arterial pulmonar e disfunção diastólica do ventrículo esquerdo. No entanto, ainda não existe consenso quanto à função sistólica ventricular nesses pacientes. O objetivo deste estudo foi o de investigar a função ventricular de pacientes com anemia falciforme utilizando o strain e o twist ventricular obtidos pelo speckle tracking bidimensional, e reconhecer os indivíduos sob maior risco cardiovascular, em que a instituição precoce de tratamento específico poderá beneficiar essa população. Métodos: Foram recrutados 40 pacientes com anemia falciforme (23,5 ± 9,3 anos; 24 homens) e 40 controles saudáveis pareados por sexo e idade, submetidos à entrevista estruturada, ecocardiograma transtorácico, cintilografia pulmonar ventilação perfusão e coleta de amostras de sangue. Todos os indivíduos foram submetidos à avaliação ecocardiográfica convencional padrão e subsequente avaliação offline do strain sistólico biventricular e estudo rotacional do ventrículo esquerdo utilizando speckle-tracking ecocardiográfico. Resultados: Os pacientes com AF apresentaram volume do VE indexado, massa do VE indexado, pressão arterial pulmonar e E/E\' médio superiores aos controles. As medidas de FE do VE, excursão sistólica do plano da tricúspide (TAPSE), Strain Global do VE (longitudinal, circunferencial, radial) e Strain Global do VD (longitudinal) não evidenciaram diferenças entre os grupos. Twist VE se mostrou reduzido em comparação aos controles (7,4 ± 1,2? vs 10,7 ± 1,8? , P <0,0001 ) e Tempo de pico de rotação apical prolongado (366,7 ± 26,1ms vs 344,6 ± 11,7ms , P <0,0001 ). Algumas variáveis se mostraram fortemente relacionadas ao twist VE, como índice de gravidade clínico (Rho= - 0,97, Z value= - 6,05, P < 0,0001), relação E/E\' médio (r = 0,94, F valor= 156.9, p<0,0001), IVDFVE (índice do volume diastólico final do ventrículo esquerdo)(r = 0,81 e p<0,0001) e pressão sistólica arterial pulmonar (r = 0,72 e p<0,0001). Conclusões: Os resultados deste trabalho indicam que o twist ventricular esquerdo derivado do speckle tracking bidimensional encontra-se alterado em pacientes com anemia falciforme e função sistólica ventricular preservada, avaliada pela metodologia convencional, e existe forte correlação entre o twist ventricular esquerdo e o índice clínico de gravidade, relação E/E\', índice do volume diastólico final do ventrículo esquerdo e pressão sistólica arterial pulmonar. / Background: Sickle cell disease (SCD) is the most prevalent hematological condition in the world, with sickle cell anemia (SCA) being its most serious form, displaying a high level of morbidity and mortality. Cardiac changes are known to be associated with SCA, including an increase in cardiac chamber size, pulmonary hypertension and left ventricle diastolic dysfunction. However, there is still no consensus regarding the ventricular systolic function in these patients. The purpose of this study is to investigate the ventricular function of patients with sickle cell anemia utilizing the strain and ventricular twist, obtained by two-dimensional speckle tracking, as well as to identify individuals with higher cardiovascular risk, in which early application of specific treatment could benefit this group of people. Methods: 40 patients were recruited with sickle cell anemia (ages 23.5 ± 9.3 years; 24 males) and 40 healthy control individuals paired by gender and age, submitted to structured interviews, transthoracic echocardiogram, pulmonary scintigraphy and collection of blood samples. All individuals were submitted to a standard echocardiographic evaluation and subsequent off line evaluation of the biventricular systolic strain and rotational study of the left ventricle using echocardiographic speckle-tracking. Results: Patients with SCA presented LV volume indices, LV mass Indices, pulmonary arterial pressure and E/ E\' ratios statistically higher than the control individuals. Measurements of Ejection Fraction (EF) of the left ventricle, tricuspid annular plane systolic excursion (TAPSE), Overall LV Strain (Longitudinal, Circumferential, and Radial) and Overall RV Strain (Longitudinal) did not present differences between the groups. LV twist was significantly lower in relation to the control group (7,4 ± 1,2? vs 10,7 ± 1,8? , P <0,0001 ) and prolonged time to peak apical rotation (366.7 ± 26.1ms vs 344.6 ± 11.7ms , P <0.0001 ). In addition, some variables showed themselves to be strongly related to LV twist such as the clinical severity index ( Rho= - 0.97, Z value= - 6.05, P < 0.0001), E/E\' Ratio (r = 0.94, F value=156.9 e p<0.0001) ), left ventricle end diastolic volume index (LVEDV index) (r = 0,81, p<0,0001) and pulmonary systolic arterial pressure (r = 0.72 e p<0.0001). Conclusions: The results of this study indicate that the left ventricular twist derived from two-dimensional speckle tracking is altered in patients with sickle cell anemia and a preserved ventricular systolic function, evaluated using conventional methodology and that there is a strong correlation between left ventricular twist and the clinical severity index, E/E\' ratio, left ventricle end diastolic volume index and the pulmonary systolic arterial pressure.
663

Análise histomorfológica de corações com atresia e estenose  mitral na síndrome do coração esquerdo hipoplásico / Histomorphologycal Analysis of Hearts with mitral atresia and stenosis in Hypoplastic Left Heart Syndrome

Décio Cavalet-Soares Abuchaim 26 August 2013 (has links)
Introdução: A Síndrome do Coração Esquerdo Hipoplásico (SCEH) compreende um espectro de malformações estruturais cardíacas caracterizadas por um hipodesenvolvimento significativo do complexo coração esquerdo-aorta, que apesar da evolução do tratamento, continua sendo um desafio. O objetivo deste trabalho é identificar diferenças morfológicas e histológicas em corações com atresia e estenose mitral na SCEH. Métodos: Estudo de 33 corações com SCEH e nove corações normais (controle), divididos em dois grupos, atresia mitral (AM) e estenose mitral (EM), obtidos em necrópsia e submetidos a análise morfológica dos segmentos da aorta, características da valva mitral e tricúspide, septo inter atrial, miocárdio, cavidades ventriculares e análise histológica com as colorações e hematoxilina/eosina e picro-sírius. Resultados: Observamos nove espécimes com Atresia Mitral e Atresia Aórtica (AMAA), 27,2%; treze com Atresia Mitral e Estenose Aórtica (AMEA), 39,3% e onze com Estenose Mitral e Estenose Aórtica (EMEA) 33,3%. Encontramos associação significativa de predominância de coronárias tortuosas no grupo EM (?2= 4,911; P=0,027) e a dominância coronariana esquerda está em 75% dos casos de EM, com diferença significativa entre os dois grupos (?2=9,298; P=0,01). No grupo AM encontramos correlação significativa entre aorta descendente e arco aórtico (r =0,692; P=0,039) e entre aorta descendente e istmo aórtico (r=0,796; P=0,010).No grupo EM, há correlação significativa entre as variáveis: Anel mitral e comprimento via de entrada de ventrículo direito (r=0,523; P=0,045); Anel mitral e istmo aórtico (r=0,692; P=0,003); ventrículo esquerdo cavidade e aorta ascendente (r=0,643; P=0,010); Arco aórtico e istmo aórtico (r=0,678; P=0,001); Aorta ascendente e arco aórtico (r=0,444; P = 0,044). Não existe diferença significativa no tamanho dos miócitos (coloração HE) entre o grupo AMAA e o grupo EMAA/EMEA (P=0,427), porém existe diferença significativa entre AMAA e controle (P=0,011) e entre EMAA/EMEA e controle (P=0,023). O percentual de colágeno (coloração de picro-sírius) é significantemente diferente entre os três grupos (P=0,0001) e o grupo AM é o que contém maior percentual de colágeno. Conclusões: 1. Na SCEH os corações com EM apresentam significativamente coronárias tortuosas e dominância coronariana esquerda em comparação com AM; 2. No grupo AM encontramos correlação significativa entre o diâmetro da aorta descendente e arco aórtico e entre aorta descendente e istmo aórtico; 3. No grupo EM, há correlação significativa entre as seguintes variáveis: anel mitral e comprimento via de entrada do ventrículo direito, anel mitral e istmo aórtico, cavidade do ventrículo esquerdo e aorta ascendente, arco aórtico e istmo aórtico e arco aórtico e aorta ascendente; 4. Há hipertrofia dos miócitos nos espécimes com AM e EM em comparação com o grupo controle; 5. Na SCEH o percentual de colágeno é superior ao grupo controle; 6. O grupo AM tem maior percentual de colágeno que o grupo EM / Introduction: Hypoplastic left heart syndrome (HLHS) comprises a spectrum of cardiac malformations characterized by a significant underdevelopment of the left heart-aorta complex, which remains a challenge despite the progress of treatment. The objective of this work is to identify morphological and histological differences in hearts with atresia and mitral stenosis with HLHS. Methods: 33 hearts with HLHS divided into two groups, mitral atresia (AM) and mitral stenosis (MS) and nine normal hearts (control),obtained at autopsy, submitted to morphological analysis of aortic segments, mitral and tricuspid valves, atrial septum, infarction, and ventricular cavities and histological study with Hematoxylin/eosin and picro sírius stain. Results: There were nine specimens with aortic atresia and mitral atresia (AMAA), 27.2%; thirteen with atresia Mitral and Aortic Stenosis (AMEA), 39.3% and eleven with Mitral Stenosis and Aortic Stenosis (EMEA) 33.3%. There is a significant association of prevalence of coronary tortuous in the MS group (x2 = 4.911, P=0.027) and left coronary dominance in 75% of cases of MS, with a significant difference between the two groups (x2 2 = 9.298, P=0,01). In the AM group we found a significant correlation between the descending aorta and aortic arch (r=0.692, P=0.039) and between the descending aorta and aortic isthmus (r =0.796, P=0.01). In the MS group there was a significant correlation between variables: mitral ring and length inlet right ventricle (r= 0.523, P=0.045), mitral and aortic isthmus (r=0.692, P=0.003), left ventricular cavity and ascending aorta (r=0.643, P=0.01); Aortic arch and aortic isthmus (r=0.678, P=0.001), ascending aorta and aortic arch (r=0.444, P=0.044).There is no significant difference in the size of myocites (HE staining) between the group and the group AMAA EMAA / EMEA (P = 0.427), but we found significant difference between AMAA and control (P = 0.011) and between EMAA / EMEA and control (P=0.023). The percentage of collagen (picrosirius staining) is different between the three groups (P=0.0001) and AM is the group that contains a higher percentage of collagen. Conclusions: 1. In HLHS hearts with MS present significant tortuous coronary and left coronary dominance compared with AM; 2. In the AM group there is a significant correlation between the diameter of the descending aorta and aortic arch and descending aorta and across the aortic isthmus; 3. In the MS group, there was significant correlation between the following variables: length and mitral inflow tract, mitral and aortic isthmus, left ventricular cavity and the ascending aorta, aortic arch and isthmus aorta and aortic arch and ascending aorta; 4. There is myocite hypertrophy in specimens with AM and EM compared with control; 5. In the HSLS collagen percentage is higher than control; 6. The AM group has a higher percentage of collagen than the EM group
664

Na čí straně stojíš? Radikální levice v poválečném Finsku - fenomén marxismu-leninismu v zemi mimo východní blok / Whose side are you on? Radical Left in postwar Finland - on the phenomenon of Marxism-Leninism outside the Eastern Bloc

Skálová, Barbora January 2021 (has links)
Barbora Skálová Whose side are you on? Radical Left in postwar Finland - on the phenomenon of Marxism-Leninism outside the Eastern Bloc Abstract The dissertation aims to explore the phenomenon of a radical left movement - Taistoists - which at the turn of the 60s and 70s for a short period of time dominated the student and cultural circles in Finland. The dissertation strives to shed light on the reasons for the uprise of the - in European context unique - pro-Soviet, Marxist-Leninist and "anti-anti- establishment" youth movement, and on its influence on home and foreign policy of Finland in terms of so-called Finlandization. The work also puts the movement into the Czechoslovakian context, mainly in relation to the 1968 Warsaw Pact invasion. The dissertation discusses the theoretical anticapitalistic background of the movement and compares it to the theoretical background and political practice of coeval New Left movements in Europe and the USA. The experience of the members of the movement has been elaborated in the oral history part based on personal interviews. The oral history chapter aims to offer an explanation and a broader perspective of the taistolaiset phenomenon presented by direct witnesses and participants of the movement.
665

UTFÖRANDE AV EJEKTIONFRAKTIONSMÄTNING MED HJÄLP AV SIMPSON METOD AV EN STUDENT OCH EN ERFAREN BIOMEDICINSK ANALYTIKER / PERFORMANCE OF EJECTION FRACTION MEASURMENT WITH SIMPSON METHOD BY A STUDENT AND AN EXPERIENCED BIOMEDICIAL SCIENTIST.

Flamarz, Diana January 2020 (has links)
Echocardiography examination is an important and familiar method for heart`s examination. Echocardiography is used to assess the function of the heart during to check the heart disease. In an echocardiography examination, the heart´s flow rates, contractility (pumping capacity), wall thickness, and inner diameter can be examined. All these examinations are done with the help of evolution of the ultrasonic waves that the ultrasonic transducer sends out and receives. The transducer consists of piezoelectric crystals that can both transmit and receive ultrasonic waves with frequencies exceeding 20 kHz. The purpose of the study is to compare the measurement of the left ventricular ejection fraction (LVEF) between an experienced biomedical scientist (BMA) and a student. In addition to see how the image quality affects the result. The measurement was performed by using the Simpson method. The result was analyzed by using with a static method. The results were analyzed by using a paired t-test to see if there is any significant difference between the performance of a BMA and a student. The measurement was performed on apical 4-chamber and apical 2-chamber image. The study included 30 patients, both heart -healthy and cardiac patients of the genders. The result showed that there is a significant difference in the performance of LVEF- measurements between BMA and student, with lower values measured by the student. / Ekokardiografiundersökning är en viktig och vanlig metod vid undersökning av hjärtat. Ekokardiografi används för att bedöma hjärtats funktion vid utredning av hjärtsjukdomar. Vid en ekokardiografiundersökning kan hjärtats flödeshastigheter, kontraktilitet (pumpförmåga), väggtjocklek, och innerdiameter undersökas. Alla dessa undersökningar görs med hjälp av tolkning av ultraljudsvågorna som ultraljudsgivaren skickar ut och tar emot. Givaren består av piezoelektriska kristaller som kan både sända och tar emot ultraljudsvågor med frekvens på över 20 kHz. Syftet med denna studie är att jämföra mätningen av den vänstra ventrikulära ejektionsfraktion (LVEF) mellan en erfaren biomedicinsk analytiker (BMA) och en student samt att se hur bildkvalitén påverkar resultatet. Mätningen utfördes med Simpsons- metoden. Resultatet analyserades med hjälp av en statistisk metod. Resultatet analyserades med hjälp av parat t-test för att se om det finns någon signifikant skillnad mellan utförandet av en BMA och en student. Mätningen utfördes på apikala 4-kammarbilder och apikala 2-kammarblider. Studien inkluderade 30 patienter, både hjärtfriska och hjärtsjuka patienter av både könen. Resultatet visade att det finns en signifikant skillnad i utförande av LVEF- mätningar mellan BMA och student, med lägre uppmätta värden av studenten.
666

Simpsons biplan metod jämfört med Philips Heart Model vid bestämning av vänsterkammares ejektionsfraktion / Simpson’s biplane method compared to the Philips Heart Model when determining the left ventricular ejection fraction

Kassem, Sara January 2021 (has links)
Introduktion: Vänsterkammarens ejektionsfraktion (VKEF) är ett central mått på systolisk funktion i vänster kammare och är en av de mest betydelsefulla parametrar vid ekokardiografiska undersökningar. Idag är Simpson biplan metoden den mest använda metoden för bestämning av ejektionsfraktionen. Vid ekokardiografiska undersökningar sänder givaren med piezoelektriska kristaller ut ultraljudsvågor med en frekvens över 20 000 Hz. Ljudvågorna som skickas ut i kroppen reflekteras och sedan återvänder de till givaren för att skapa en bild. Denna studie jämför den tvådimensionella (2D) ultraljudsmetoden Simpsons biplan med Philips Heart Model som är en automatiserad tredimensionella (3D) funktion för bedömning av VKEF.  Material och metod: I studien inkluderades 31 hjärtfriska försökspersoner mellan åldrarna 21-64. Det samlades in bilder på apikala 4- och 2 kammarbilder från alla försökspersoner där Simpsons biplan metoden användes för att beräkna ejektionsfraktion. Apikala 4-kammarbilder samlades in för att beräkna ejektionsfraktionen med Philips Heart Model 3D funktion.  Resultat: Resultatet från denna studie visade att det inte föreligger någon signifikant skillnad mellan Simpsons biplan metoden och Philips Heart Model metoden för bestämning av ejektionsfraktion. Båda metoderna visade likvärdiga mätresultat.  Diskussion: Philips Heart Model metoden är en relativ ny funktion som använder sig av artificiell intelligens för att analysera 3D bilder. Philips Heart Model metoden är en säker funktion att använda då de flesta studier bevisar likvärdiga och säkra mätresultat i jämförelse med andra metoder.  Konklusion: Enligt denna studie ger Philips Heart Model funktionen likvärdiga mätresultat av vänsterkammarens ejektionsfraktion i jämförelse med Simpsons biplan. / Introduction: Simpson’s biplane method is the most used method for determining the left ventricular ejection fraction (LVEF) in echocardiographic examinations. Ejection fraction is a central measurement of the heart's global systolic function. The probe with piezoelectric crystals emits ultrasound waves with a frequency above 20,000 Hz. The sound waves that are sent out into the body are reflected and then return to the probe to create an image. This study compares the two-dimensional (2D) ultrasound Simpson's biplane method with the Philips Heart Model method, which is an automated three-dimensional (3D) function for assessment of LVEF.                                                                                                                          Material and method: 31 subjects with no recorded heart pathologies between the ages of 21-64 were included in the study. Apical 4- and 2-chamber images were collected from the test subjects, where the Simpson's biplane method was applied to calculate the ejection fraction. 2D apical 4-chamber images were collected to convert to 3D and used to calculate the ejection fraction with the Philips Heart Model.    Results: The results of this study showed that there is no significant difference between the Simpson’s biplane method and the Philips Heart Model method for determining ejection fraction.    Discussion: The Philips Heart Model method is a relatively new feature that uses artificial intelligence to analyze 3D images. The Philips Heart Model method is a reliable feature to use as most studies have proven similar and reliable measurements when comparing it with other methods for determining LVEF.    Conclusion: According to this study, the Philips Heart Model feature provides equivalent measurements in comparison with the manual method Simpson's biplane.
667

Conspiracy theories as counter-knowledge : alternative approaches to the current crisis of the capitalist system

Hegstad, Vegard 04 1900 (has links)
Thesis (MA)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The aim of the study is to identify and analyse conspiracy narratives as popular counter-knowledge and as alternatives to leftist discourse and explanations of the contradictions of a capitalist system in a systemic crisis. The study makes a distinction between pathological and cultural approaches to conspiracy theories. While pathological approaches critically assess conspiracy theories as expressions of a certain political paranoia, cultural approaches are more inclusive and view conspiracy theory as cultural expressions of the postmodern condition. The cultural understandings break the categorical link between conspiracy theories and irrationality and allows a further discussion on how conspiracy theories might relate to leftist discourse and its attempts to counter neoliberal hegemonic structures. The approach taken by the study relies on the theoretical framework of historical materialism. Key theories used derive from Karl Marx, along with Gramscian, World Systems theory and critical approaches to global political economy. In the historical analysis that was performed, the understanding of structures in the historical development of the world economy, as well as the role of social forces which lead to changes in these structures were shown to be better approaches for understanding both historical events and the current crisis in the capitalist system. However, even within the opportune movement of an on-going capitalist crisis, the Left struggles to create a consistent counter-hegemonic narrative, and current counter-hegemonic movements, whilst being influential, are not succeeding in being transformative This suggests that leftist discourse fails to address the micro-level manifestations of the contradictions of the current system in a way that appeals to the masses. Accordingly, conspiracy theories as frameworks from which to critique the current global political economy are discussed. It is argued that although conspiracy theories are essentially reactionary, as well as historically a product of the far right, these theories might be understood as allegorical narrative constructs that serve as tools of orientation in a confusing political reality and, as such, the label of irrationality should not be applied without further consideration. It is further suggested that there is a proximity between various critical perspectives and conspiracy theories, although it is not implied that there is an exchange of ideas. It is argued that strands of critical theory and conspiracy theory share certain convictions about how the social world is constructed. While leftist/critical discourse relies on a scientific historical analysis, conspiracy discourses are often categorised lacking in scientific support. Critical theoretical perspectives are therefore suggested as the most effective remedy against utopian and simplistic narratives. While the thesis does not challenge the appropriateness of Marxist/critical perspectives at explaining economic crisis and global inequity, it aims at discussing the popularity of conspiracy theories as, for many, preferable tools of orientation in the present times. While political scientific theories and conspiracy theories are generally understood as in essence incompatible, this thesis attempted to discuss and analyse whether this established view could be challenged in light of recent scholarship on conspiracy culture. The study concludes that Marxist/critical approaches should understand conspiracy theories as alternative counter-knowledge and as popular doorways into major social issues that define global political culture, which could actually complement traditional leftist discourse. / AFRIKAANSE OPSOMMING: Die doel van die studie is om sameswerings-verhale as populêre teen-kennis en as alternatiewe vir linkse diskoers en verklarings van die teenstrydighede van ’n kapitalistiese stelsel wat ’n sistemiese krisies beleef, te identifiseer en te analiseer. Die studie onderskei tussen patalogiese en kulturele benaderings tot samesweringsteorieë. Patologiese benaderinge raam samesweringsteorieë krities as uitdrukkings van bepaalde politieke paranoia, terwyl kulturele benaderinge meer inklusief is, samesweringsteorie beskou as ’n kulturele uitdrukking van die postmoderne toestand. Die kulturele begrip breek die kategoriese skakel tussen samesweringsteorieë en irrasionaliteit en fasiliteer nog ’n gesprek oor hoe hierdie teorieë moontlik verwant sou kon wees aan linkse diskoers, asook laasgenoemde se pogings om neoliberale hegemoniese strukture teen te staan. Die benadering wat gevolg word in die studie steun op die teoretiese raamwerk van historiese materialisme. Die vernaamste vertrekpunte wat gebruik word is afgelei van Karl Marx, tesame met Gramsciaanse, Wêreldstelsel-teorie en kritiese benaderings tot globale politieke ekonomie. In die historiese analiese wat onderneem is, word gedemonstreer dat ’n begrip van strukture in die historiese ontwikkeling van die wêreld-ekonomie, asook die rol van sosiale magte wat verandering in hierdie strukture meebring, beter verklarings bied vir beide historiese gebeure en die teenswoordige krisies in die kapitalistiese stelsel. Nietemin, selfs met die geleenthede wat geskep word te midde van die aangaande kapitalistiese krisies, sukkel Linksgesindes om ’n konsekwente teen-hegemoniese “verhaal” te skep. Kontemporêre teen-hegemoniese bewegings, ongeag hul skynbare invloed, slaag nie daarin om verandering te weeg te bring nie. Dit wil voorkom asof linkse diskoers nie daarin slaag om die manifistering van die teenswoordige stelsel se teenstrydighede aan te spreek op ’n wyse wat aanklank vind by die massas nie. Dienooreenkomstig word samesweringsteorieë bespreek as raamwerke vanwaar en waaruit die huidige globale politieke ekonomie gekritiseer kan word. Die argument word aangevoer dat, alhoewel hierdie teorieë essensieel reaksionêr is, asook histories gesien ’n verregse produk, hulle moontlik verstaan kan word as allegoriese verhaal konstrukte wat dien as middele vir orientasie in ’n verwarrende politieke werklikheid. As sulks, behoort die etiket van irrasionaliteit nie sondermeer en onkrities aan hulle toegedien te word nie. Verder, word daar in die studie voorgestel, dat daar raakpunte is tussen verskeie kritiese perspektiewe en samesweringsteorieë. Daar word egter nie gesuggereer dat daar ’n uitruil van idees is nie. Daar word egter wel ge-argumenteer dat daar elemente van kritiese teorieë en samesweringsteorieë is wat bepaalde oortuiginge deel oor hoe die sosiale werklikheid gevorm word. Terwyl linkse en kritiese diskoers gekoppel is aan wetenskaplike-historiese analise, word samesweringsdiskoerse gekategoriseer as verklarings wat gebrek lei aan wetenskaplike ondersteuning. Kritiese teoretiese perspektiewe word dus voorgehou as die mees effektiewe oplossing teen utopieseen simplistiese narratiewe. Terwyl die tesis nie die toepasbaarheid van Marxistiese/Kritiese perspektiewe, as verklarings vir die ekonomiese krisies en globale ongelykheid, uitdaag nie, het dit gepoog om die populariteit van samesweringsteorieë, as voorkeur raamwerke vir orientering in teenswoordige tye, aan te spreek. Die tesis het onderneem om vas te stel en te analiseer of die algemeen aanvaarde aanname dat politiek wetenskaplike teorieë en samesweringsteorieë essensieel onversoenbaar is, uitgedaag kan word, gesien in die lig van onlangse akademiese werk oor samesweringskultuur. Die studie bevind dat Marxistiese/kritiese benaderings samesweringsteorieë behoort te verstaan as alternatiewe teen-kennis en as populêre ingangspunte tot belangrike sosiale kwessies wat die globale politieke kultuur definieer. In die sin, sou samesweringsteorieë selfs tradisionele linkse diskoers kon aanvul.
668

Prospective left ventricular lead targeting in cardiac resynchronisation therapy

Khan, Fakhar Zaman January 2014 (has links)
No description available.
669

INFLAMMATORY INTERACTIONS AND SECRETION IN CARDIAC REMODELING

Yang, Fanmuyi 01 January 2012 (has links)
Heart failure contributes to nearly 60,000 deaths per year in the USA and is often caused by hypertension and preceded by the development of left ventricular hypertrophy (LVH). LVH is usually accompanied by intensive interstitial and perivascular fibrosis which may contribute to arrhythmogenic sudden cardiac death. Emerging evidence indicates that LV dysfunction in patients and animal models of cardiac hypertrophy is closely associated with perivascular inflammation. To investigate the role of perivascular inflammation in coronary artery remodeling and cardiac fibrosis during hypertrophic ventricular remodeling, we used a well-established mouse model of pressure-overload-induced LVH: transverse aortic constriction (TAC). Early perivascular inflammation was indicated by accumulation of macrophages and T lymphocytes 24 hours post-TAC and which peaked at day 7. Coronary luminal platelet deposition was observed along with macrophages and lymphocytes at day 3. Also, LV protein levels of VEGF and MCP-1 were significantly increased. Consistent with lymphocyte accumulation, cardiac expression of IL-10 mRNA was elevated. Furthermore, circulating platelet-leukocyte aggregates tended to be higher after TAC, compared to sham controls. Platelets have been shown to modulate perivascular inflammation and may facilitate leukocyte recruitment at sites of inflamed endothelium. Therefore, we investigated the impact of thrombocytopenia in the response to TAC. Immunodepletion of platelets decreased early perivascular accumulation of T lymphocytes and IL-10 mRNA expression, and altered subsequent coronary artery remodeling. The contribution of lymphocytes was examined in Rag1-/- mice, which displayed significantly more intimal hyperplasia and perivascular fibrosis compared to wild-type mice following TAC. Collectively, our studies support a role of early perivascular accumulation of platelets and T lymphocytes in pressure overload-induced inflammation which will contribute to long-term LV remodeling. One potential mechanism for inflammatory cells to modulate their environment and affect surrounding cells is through release of cargo stored in granules. To determine the contribution of granule release from inflammatory cells in the development of LVH, we used Unc13dJinx (Jinx) mice, which contain a single point mutation in Unc13d gene resulting in defects in Munc13-4. Munc13-4 is a limiting factor in vesicular priming and fusion during granule secretion. Therefore, Jinx mice have defects in degranulation of platelets, NK cells, cytotoxic T lymphocytes, neutrophils, mast and other cells. With the use of bone marrow transplantation, Jinx chimeric mice were created to determine whether the ability of hematopoietic cells to secrete granule contents affects the development of LVH. Wild-type mice (WT) that were transplanted with WT bone marrow (WT>WT) and WT mice that received Jinx bone marrow (Jinx>WT) developed LVH and a classic fetal reprogramming response early after TAC (7 days), but at later times (5 weeks), Jinx>WT mice failed to sustain the cardiac hypertrophic response observed in WT>WT mice. No difference in cardiac fibrosis was observed at early or late times. Repetitive injection of WT platelets or platelet releasate restored cardiac hypertrophy in Jinx>WT mice. These results suggest that sustained LVH in the setting of pressure overload depends on factor(s) secreted, likely from platelets. In conclusion, our studies demonstrate that platelets and lymphocytes are involved in early perivascular inflammation post-TAC, which may contribute to later remodeling in the setting of LVH. Factors released from hematopoietic cells, including platelets, in a Munc13-4-dependent manner are required to promote cardiac hypertrophy. These findings focus attention on modulating perivascular inflammation and targeting granule cargo release to prevent the development and consequences of LVH.
670

Alberta's Red Democrats: The Challenge and Legacy of Blairmore Communism, 1921-1936

Franz, Kyle Randolph 29 August 2013 (has links)
On Valentine’s Day, 1933 the citizens of Blairmore, Alberta elected a Communist town council and school board. “Alberta’s Red Democrats: the Challenges and Legacy of Blairmore Communism, 1921-1936” seeks not only to understand the Red administration that governed here during the mid-thirties, but also the community that elected it. It will be shown that the election of Mayor Bill Knight and his colleagues was neither a knee-jerk reaction to the protracted poverty of the Great Depression nor an alignment with the Communist Party of Canada as an act of desperation. The Red movement at Blairmore was deeply rooted in past experience, and as it came to fruition challenged what it meant to be a Communist in Canada. / Thesis (Ph.D, History) -- Queen's University, 2013-08-29 17:24:15.163

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