Proximal femoral focal deficiency: radiologic analysis of 49 cases

Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification.     

Acetabular posterior wall fracture. 38 cases followed for 5 years

Thirty-eight patients with a fracture of the posterior wall of the acetabulum were reviewed after 5 (2-12) years. Of 18 patients with successful manual reduction of a femoral head dislocation, a small fracture fragment, no sciatic nerve injury and who were not operated on, 17 had a good result. Of 20 patients who were operated on either because of the large size of the fracture fragment or because of a persistent dislocation of the femoral head, 6 had a poor result due to femoral head necrosis. In these 6 patients the reduction had been delayed and the acetabular osteochondral lesion was more severe than in the other patients. Skeletal traction seems unnecessary in the treatment of acetabular posterior wall fracture.     

An immunoglobulin superfamily-like domain unique to the Yersinia pseudotuberculosis invasin protein is required for stimulation of bacterial uptake via integrin receptors

The binding of the Yersinia pseudotuberculosis and Yersinia enterocolitica invasin proteins to beta(1) integrin receptors allows internalization of these organisms by cultured cells. The C-terminal 192-residue superdomain of the Y. pseudotuberculosis invasin is necessary and sufficient for integrin recognition, while a region located outside, and N-terminal to, this superdomain strongly enhances the efficiency of bacterial uptake. Within the enhancer region is a domain called D2 that allows invasin-invasin interaction. To investigate the role of the enhancer region, bacterial cell binding and entry mediated by the Y. pseudotuberculosis invasin protein (invasin(pstb)) was compared to that of Y. enterocolitica invasin (invasin(ent)), which lacks the D2 self-association domain. Invasin(ent) was shown to be unable to promote self-interaction, using the DNA binding domain of lambda repressor as a reporter. Furthermore, two genetically engineered in-frame deletion mutations that removed D2 from invasin(pstb) were significantly less proficient than wild-type invasin(pstb) at promoting uptake, although the amount of surface-exposed invasin as well as the cell binding capacity of the recombinant Escherichia coli strains remained similar. Competitive uptake assays showed that E. coli cells expressing invasin(pstb) had a significant advantage in the internalization process versus either E. coli cells expressing invasin(ent) or the invasin(pstb) derivatives deleted for D2, further demonstrating the importance of invasin self-interaction for the efficiency of invasin-mediated uptake.     

Life expectancy in British Marfan syndrome populations

A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome.