The 'Hip Vacuum Sign'-a new radiographic phenomenon in femoro-acetabular impingement.

Femoro-acetabular impingement (FAI) is a frequent cause for groin pain in young and active patients. We discovered a so far undescribed radiographic phenomenon only visible in frog-leg lateral radiographs. The aim of this study was to describe this new radiological sign, to determine its prevalence in a symptomatic population and to investigate the correlation to a potential underlying pathology.

Geranylgeranyl pyrophosphate is crucial for neuronal survival but has no special role in Purkinje cell degeneration in Niemann Pick type C1 disease.

Niemann Pick type C (NPC1) is a rare fatal hereditary cholesterol storage disease associated with a massive Purkinje cells loss. The mechanisms leading to neurodegeneration are still poorly understood. Different laboratories pointed to hypersensitivity to cytotoxic effects of statins (HMG-CoA reductase inhibitors) in NPC1 and suggested an underlying lack of geranylgeranyl pyrophosphate (GGPP).

The natural history of cerebellar degeneration of Niemann-Pick C mice monitored in vitro.

Aims: Niemann-Pick type C (NPC) disease is a fatal hereditary lysosomal lipid storage disease caused by mutations in NPC1 or NPC2. It is still unknown how this disorder evokes clinical signs. Typically, patients develop severe cerebellar ataxia due to progressive Purkinje cell loss.