[Magnetic resonance imaging of hypertrophic cardiomyopathy : evaluation of diastolic function]

Hypertrophic cardiomyopathy (HCM) has a prevalence of approximately 0.2% and is clinically asymptomatic in many patients or presents with unspecific symptoms. This explains the importance of imaging for the diagnosis of HCM as well as for the assessment of the clinical course. The definitive finding in HCM is myocardial hypertrophy with thickening of the ventricular wall ≥ 15 mm. While echocardiography is an excellent screening tool magnetic resonance imaging (MRI) allows a comprehensive analysis of the heart in HCM. This includes a detailed analysis of the distribution and extent of myocardial hypertrophy, a thorough evaluation of systolic and diastolic cardiac function, the assessment of the presence and extent of dynamic outflow tract obstruction as well as the description of the systolic anterior motion (SAM) phenomenon of the mitral valve with secondary mitral insufficiency. When contrast material is administered, additional information about myocardial perfusion as well as the presence and extent of myocardial fibrosis can be obtained. This study compared systolic functional parameters as well as end systolic and end diastolic wall thickness of patients with and without diastolic dysfunction.

Ascorbic acid induces lipid peroxidation on neuroectodermal SK-N-LO cells with high endogenous ferritin content and loaded with MAb-ferritin immunoconjugates

Neuroblasma-and other malignant cells often contain elevated amounts of iron-rich ferritin and H2O2 and may therefore be a potential target for pro-oxidative effects of ascorbic acid (AA), generating cytotoxic products e.g. by lipid peroxidation (LPO). The influence of H2O2 and iron, either in its free form or bound to ferritin, on AA induced LPO was first investigated using erythrocyte ghosts as a model system. Results of these experiments showed that AA induced LPO not only in the presence of free available iron but also in the presence of ferritin. Similarly, AA induced significant LPO in neuroectodermal SK-N-LO cells with elevated intracellular ferritin levels. These LPO promoting effects of ferritin in the presence of AA on SK-N-LO cells could also be observed using ferritin-immunoconjugates: for this purpose, ferritin was bound to human monoclonal antibodies (MAb-ferritin) recognizing ganglioside GD2 which is present in large quantities on cell surfaces of SK-N-LO and many neuroblastoma cells. We conclude that the pro-oxidative effects of AA could be exploited in the treatment of ferritin rich neuroblastoma in combination with chemotherapy or with MAb-ferritin immunoconjugates.