Increased baroreceptor sensitivity in a patient with hereditary spastic paraplegia – type SPG11

An 18 years old male patient was diagnosed with genetically confirmed hereditary spastic paraplegia of type SPG11 - a rare disease of neurodegeneration. During normal clinical routine investigation, he presented with a moderate sinus bradycardia. The function of the cardiovascular system was investigated by recording electrocardiogram, impedance cardiogram and continuous blood pressure non-invasively. Cardiac function appeared normal in all modalities. Baroreflex sensitivity was strongly increased by a factor of 2.8. Results indicate that further to hyperactivity of deep tendon reflexes, also the responsiveness regarding control of heart rhythm by baroreceptors is significantly increased. This finding provides evidence for the impact of a neurological disorder onto the cardiovascular system and its autonomic control

Changes in plasma amino acid concentrations with increasing age in patients with propionic acidemia

The objective of the study is to analyze plasma amino acid concentrations in propionic acidemia (PA) for the purpose of elucidating possible correlations between propionyl-CoA carboxylase deficiency and distinct amino acid behavior. Plasma concentrations of 19 amino acids were measured in 240 random samples from 11 patients (6 families) with enzymatically and/or genetically proven propionic acidemia (sampling period, January 2001-December 2007). They were compared with reference values from the literature and correlated with age using the Pearson correlation coefficient test. Decreased plasma concentrations were observed for glutamine, histidine, threonine, valine, isoleucine, leucine, phenylalanine and arginine. Levels of glycine, alanine and aspartate were elevated, while values of serine, asparagine, ornithine and glutamate were normal. For lysine, proline and methionine a clear association was not possible. Significant correlations with age were observed for 13 amino acids (positive correlation: asparagine, glutamine, proline, alanine, histidine, threonine, methionine, arginine; negative correlation: leucine, phenylalanine, ornithine, glutamate and aspartate). This study gives new insight over long-term changes in plasma amino acid concentrations and may provide options for future therapies (e.g., substitution of anaplerotic substances) in PA patients