Update on Ankle and Foot Impingement.

Ankle impingement syndromes are a well-recognized cause of chronic ankle symptoms in both the elite athletic and general population. They comprise several distinct clinical entities with associated radiologic findings. Originally described in the 1950s, advances in magnetic resonance imaging (MRI) and ultrasonography have allowed musculoskeletal (MSK) radiologists to further their understanding of these syndromes and the range of imaging-associated features. Many subtypes of ankle impingement syndromes have been described, and precise terminology is critical to carefully separate these conditions and thus guide treatment options. These are divided broadly into intra-articular and extra-articular types, as well as location around the ankle. Although MSK radiologists should be aware of these conditions, the diagnosis remains largely clinical, with plain film or MRI used to confirm the diagnosis or assess a surgical/treatment target. The ankle impingement syndromes are a heterogeneous group of conditions, and care must be taken not to overcall findings. The clinical context remains paramount. Treatment considerations are patient symptoms, examination, and imaging findings, in addition to the patient's desired level of physical activity.

Automated parallel DNA sequencing on multiple channel microchips.

We report automated DNA sequencing in 16-channel microchips. A microchip prefilled with sieving matrix is aligned on a heating plate affixed to a movable platform. Samples are loaded into sample reservoirs by using an eight-tip pipetting device, and the chip is docked with an array of electrodes in the focal plane of a four-color scanning detection system. Under computer control, high voltage is applied to the appropriate reservoirs in a programmed sequence that injects and separates the DNA samples. An integrated four-color confocal fluorescent detector automatically scans all 16 channels. The system routinely yields more than 450 bases in 15 min in all 16 channels. In the best case using an automated base-calling program, 543 bases have been called at an accuracy of >99%. Separations, including automated chip loading and sample injection, normally are completed in less than 18 min. The advantages of DNA sequencing on capillary electrophoresis chips include uniform signal intensity and tolerance of high DNA template concentration. To understand the fundamentals of these unique features we developed a theoretical treatment of cross-channel chip injection that we call the differential concentration effect. We present experimental evidence consistent with the predictions of the theory.

Medical response to a natural disaster: the Barrie tornado.

On May 31, 1985, a tornado devastated an area of Barrie, Ont. Following a prepared disaster plan, the staff of the local hospital managed 155 casualties, including 16 cases of multiple trauma, over 5 hours. The authors summarize the hospital's experience and give recommendations to help the staff of other hospitals improve their disaster plans.