Co-occurrence of subchondral insufficiency fracture of the femoral head and contralateral femoral neck fracture in a rheumatic patient receiving steroid treatment.

We describe a 79-year-old woman with rheumatoid arthritis who suffered from subchondral insufficiency fracture of the femoral head (SIF) and contralateral femoral neck fracture. Radiographs obtained two months after the onset of thigh pain showed collapse of the right femoral head and contralateral femoral neck fracture. MRI revealed a subchondral serpiginous low-intensity band in the right femoral head on the T2-weighted image.

Temperature-sensitive defects of the GSP1gene, yeast Ran homologue, activate the Tel1-dependent pathway.

RanGTPase is involved in many cellular processes. It functions in nuclear-cytosolic transport and centrosome formation. Ran also localizes to chromatin as RCC1 does, its guanine nucleotide exchange factor, but Ran's function on chromatin is not known.