Homophily and acrophily as drivers of political segregation.

Political segregation is an important social problem, increasing polarization and impeding effective governance. Previous work has viewed the central driver of segregation to be political homophily, the tendency to associate with others who have similar views. Here we propose that, in addition to homophily, people's social tie decisions are driven by political acrophily, the tendency to associate with others who have more extreme political views (rather than more moderate).

Vertebral deformities identified by vertebral fracture assessment: associations with clinical characteristics and bone mineral density.

Whether vertebral fractures identified on radiographs are painful or not, they are associated with increased morbidity and mortality. Vertebral fractures on X-rays correlate with low bone mineral density (BMD) at the spine and hip in addition to several clinical characteristics. Evidence suggests that vertebral deformities detected by X-ray and by vertebral fracture assessment (VFA) show good agreement.

Leflunomide induced fevers, thrombocytosis, and leukocytosis in a patient with relapsing polychondritis.

The most common adverse events reported with the use of leflunomide are hypertension, infections, alopecia, and various gastrointestinal complaints. No fatal adverse hematologic events have been reported in humans, although anemia and leukopenia have been described in animals receiving 20 mg/kg/day. We describe a patient with relapsing polychondritis, in whom treatment failure with glucocorticoids, methotrexate, hydroxychloroquine, and azathioprine led to the institution of therapy with leflunomide at a maintenance dose of 20 mg/day.

Collection of genomic DNA from adults in epidemiological studies by buccal cytobrush and mouthwash.

Blood samples are an excellent source of large amounts of genomic DNA. However, alternative sources are often needed in epidemiological studies because of difficulties in obtaining blood samples. This report evaluates the buccal cytobrush and alcohol-containing mouthwash protocols for collecting DNA by mail.

Assessment of small-diameter aortic mechanical prostheses: physiological relevance of the Doppler gradient, utility of flow augmentation, and limitations of orifice area estimation.

Background: Noninvasive assessment of functionally stenotic small-diameter aortic mechanical prostheses is complicated by theoretical constraints relating to the hemodynamic relevance of Doppler-derived transprosthetic gradients. To establish the utility of Doppler echocardiography for evaluation of these valves, 20-mm Medtronic Hall and 19-mm St Jude prostheses were studied in vitro and in vivo.

Methods And Results: Relations between the orifice transprosthetic gradient (equivalent to Doppler), the downstream gradient in the zone of recovered pressure (equivalent to catheter), and fluid mechanical energy losses were examined in vitro.