879 resultados para Cardiac MR


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Electronic report

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: As progress is made towards attaining Millennium Development Goal 4, further reductions in paediatric mortality will only be achieved by concentrating on the burden of non-communicable or neglected diseases. The literature relating to paediatric cardiac disease in sub-Saharan Africa is sparse. There are no published descriptions of paediatric cardiac disease from Malawi, making it impossible to estimate the contribution it makes to childhood morbidity and mortality.

FINDINGS: In 2008, a paediatric cardiac clinic with echocardiogram scanning was established in Blantyre, southern Malawi. Between January 2009 and February 2011, the age and cardiac diagnosis of every child with an abnormal echocardiogram was recorded in a database. Of 250 children, 139 (55.6%) had congenital heart disease, and 111 (44.4%) acquired heart disease. Ventricular septal defect (VSD) (24%), Tetralogy of Fallot (10%) and patent ductus arteriousus (7.2%) were the commonest forms of congenital heart disease. Rheumatic heart disease (RHD) (22.4%) and dilated cardiomyopathy (13.6%) were the commonest acquired diseases. The mean age of presentation was 3 years 2 months for VSD and 11 years 6 months for RHD.

CONCLUSIONS: In this cohort of children from one centre in Malawi, acquired heart disease - in particular rheumatic heart disease was almost as common as congenital heart disease. Most presented late. It is likely that untreated cardiac disease causes a large number of childhood deaths in Malawi. In addition to renewing secondary preventative efforts against rheumatic heart disease, adequate and accessible cardiothoracic surgical services should be established at a regional level.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In the past few years a new generation of multifunctional nanoparticles (NPs) has been proposed for biomedical applications, whose structure is more complex than the structure of their predecessor monofunctional counterparts. The development of these novel NPs aims at enabling or improving the performance in imaging, diagnosis and therapeutic applications. The structure of such NPs comprises several components exhibiting various functionalities that enable the nanoparticles to perform multiple tasks simultaneously, such as active targeting of certain cells or compartmentalization, imaging and delivery of active drugs. This thesis presents two types of bimodal bio-imaging probes and describes their physical and chemical properties, namely their texture, structure, and 1H dynamics and relaxometry, in order to evaluate their potential as MRI contrast agents. The photoluminescence properties of these probes are studied, aiming at assessing their interest as optical contrast agents. These materials combine the properties of the trivalent lanthanide (Ln3+) complexes and nanoparticles, offering an excellent solution for bimodal imaging. The designed T1- type contrast agent are SiO2@APS/DTPA:Gd:Ln or SiO2@APS/PMN:Gd:Ln (Ln= Eu or Tb) systems, bearing the active magnetic center (Gd3+) and the optically-active ions (Eu3+ and Tb3+) on the surface of silica NPs. Concerning the relaxometry properties, moderate r1 increases and significant r2 increases are observed in the NPs presence, especially at high magnetic fields, due to susceptibility effects on r2. The Eu3+ ions reside in a single low-symmetry site, and the photoluminescence emission is not influenced by the simultaneous presence of Gd3+ and Eu3+. The presence of Tb3+, rather than Eu3+ ion, further increases r1 but decreases r2. The uptake of these NPs by living cells is fast and results in an intensity increase in the T1-weighted MRI images. The optical features of the NPs in cellular pellets are also studied and confirm the potential of these new nanoprobes as bimodal imaging agents. This thesis further reports on a T2 contrast agent consisting of core-shell NPs with a silica shell surrounding an iron oxide core. The thickness of this silica shell has a significant impact on the r2 and r2* relaxivities, and a tentative model is proposed to explain this finding. The cell viability and the mitochondrial dehydrogenase expression given by the microglial cells are also evaluated.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Cachexia is a complex syndrome characterized by severe weight loss frequently observed in cancer patients and associated with poor prognosis. Cancer cachexia is also related to modifications in cardiac muscle structure and metabolism leading to cardiac dysfunction. In order to better understand the cardiac remodeling induced by bladder cancer and the impact of exercise training after diagnosis on its regulation, we used an animal model of bladder cancer induced by exposition to N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) in the drinking water. Healthy animals and previously BBN exposed animals were submitted to a training program in a treadmill at a speed of 20m/min, 60 min/day, 5 days/week during 13 weeks. At the end of the protocol, animals exposed to BBN presented a significant decrease of body weight, in comparison with control groups, supporting the presence of cancer cachexia. Morphological analysis of the cardiac muscle sections revealed the presence of fibrosis and a significant decrease of cardiomyocyte’s cross-sectional area, suggesting the occurrence of cardiac dysfunction associated with bladder cancer. These modifications were accompanied by heart metabolic remodeling characterized by a decreased fatty acid oxidation given by diminished levels of ETFDH and of complex II subunit  from the respiratory chain. Exercise training promoted an increment of connexin 43, a protein involved in cardioprotection, and of c-kit, a protein present in cardiac stem cells. These results suggest an improved heart regenerative capacity induced by exercise training. In conclusion, endurance training seems an attractive non-pharmacological therapeutic option for the management of cardiac dysfunction in cancer cachexia.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This speech by Mr. Memminger offers resolutions on the issue of rechartering the bank of the state of South Carolina. The issues presented are the Bank of the State is founded on an erroneous policy, unwise for a state to engage in banking, not practical to recharter the Bank of the State and a special committee of each house should be appointed to advise how to carry out these resolutions at the next session.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This document contains the facts and arguments in favor of the bill, which he was prevented from presenting before the House of Representatives at the last session of the legislature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The speech addresses the question, how can the union be preserved? He goes on to explain the threats to the union and give suggestions for how the threats can be handled.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tese de mestrado. Biologia (Biologia Evolutiva e do Desenvolvimento). Universidade de Lisboa, Faculdade de Ciências, 2014

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction: Coronary heart disease (CHD) is one of the leading causes of death in both men and women worldwide. Despite the common misconception that CHD is a ‘man's disease’, it is now well accepted that women endure worse clinical outcomes than men following CHD-related events. A number of studies have explored whether or not gender differences exist in patients presenting with CHD, and specifically whether women delay seeking help for cardiac conditions. UK and overseas studies on help-seeking for emergency cardiac events are contradictory, yet suggest that women often delay help-seeking. In addition, no studies have looked at presumed cardiac symptoms outside an emergency situation. Given the lack of understanding in this area, an explorative qualitative study on the gender differences in help-seeking for a non-emergency cardiac events is needed. Methods and analysis: A purposive sample of 20–30 participants of different ethnic backgrounds and ages attending a rapid access chest pain clinic will be recruited to achieve saturation. Semistructured interviews focusing on help-seeking decision-making for apparent cardiac symptoms will be undertaken. Interview data will be analysed thematically using qualitative software (NVivo) to understand any similarities and differences between the way men and women construct help-seeking. Findings will also be used to inform the preliminary development of a cardiac help-seeking intentions questionnaire. Ethics and dissemination: Ethical approvals were sought and granted. Namely, the University of Westminster (sponsor) and St Georges NHS Trust REC, and the Trust Research and Development Office granted approval to host the study on the Queen Mary's Roehampton site. The study is low risk, with interviews being conducted on hospital premises during working hours. Investigators will disseminate findings via presentations and publications. Participants will receive a written summary of the key findings.