Edge enhancement of ECG-gated cardiac images using directional masks

ECG-gated images were processed by a computer using a nonlinear digital filter and directional masks to improve delineation of cardiac chamber boundaries and identification of the aortic and mitral valve planes. This technique proved to be satisfactory in 30 patients with documented coronary or valvular heart disease.     

Emergency department utilization by adolescents in the United States

BACKGROUND: Adolescents in the United States have been shown to underutilize primary care services and therefore may rely heavily on emergency service. Although several small studies have explored local emergency services for youth, there are no published reports of adolescent utilization of emergency services on a national scale. Furthermore, emergency services data have not been aggregated according to the age subgroups used by the current guidelines for adolescent care. OBJECTIVE: To explore the utilization of emergency departments in the United States by early (11 to 14 years), middle (15 to 17 years), and late (18 to 21 years) adolescent subgroups. DESIGN: Secondary analysis of the emergency department component of the 1994 National Hospital Ambulatory Medical Care Survey. SETTING: Nationally representative sample of 418 emergency departments in the United States. PATIENTS: Approximately 26,547 visits by patients of all ages, representing 93.4 million total visits in 1994 and 14.8 million adolescent visits. OUTCOME MEASURES: Number of visits, health insurance, reasons for visits, urgency of visits, resulting diagnoses, and hospitalization rates. RESULTS: Adolescents accounted for 15.4% of the population and 15.8% of emergency department visits in 1994. Late adolescents were overrepresented in emergency department visits relative to their population proportion (6.8% of visits, 5.3% of population), whereas early adolescents were underrepresented (4.6% of visits, 5.9% of population). Lack of health insurance was more common among 11- to 21-year-olds (26.2%) than either children (13.6%) or adults (22.7%). By ages 18 to 21 years, 40.5% of male visits and 27.6% of female visits were uninsured. Injury-related visits were more common among adolescents (28.6%) than either children (23.1%) or adults (18.2%). Injury was the leading reason for visits among all adolescent age-sex subgroups (36.6% to 42.0% of male visits and 14.1% to 27.2% of female visits) except females aged 18 to 21 years for whom digestive reasons ranked first (18.8%). Injury was the leading diagnosis for all adolescent age-sex subgroups, with peaks at early adolescence of 61.6% for males and 45.8% for females. Across all adolescent age-sex subgroups, 3.1% to 5.3% of visits resulted in hospitalization, and 41.0% to 52.5% of visits were urgent. These rates did not differ from those of children but were lower than those of adults. CONCLUSIONS: Utilization of emergency departments increases and health insurance decreases during adolescence, suggesting that adolescents with inadequate health insurance may rely heavily on emergency departments for their health care needs. Most adolescent visits to emergency departments are not urgent and might be better treated through nonemergency, primary care sites.     

Fine-scale human genetic structure in Western France

The difficulties arising from association analysis with rare variants underline the importance of suitable reference population cohorts, which integrate detailed spatial information. We analyzed a sample of 1684 individuals from Western France, who were genotyped at genome-wide level, from two cohorts D.E.S.I.R and CavsGen. We found that fine-scale population structure occurs at the scale of Western France, with distinct admixture proportions for individuals originating from the Brittany Region and the Vendée Department. Genetic differentiation increases with distance at a high rate in these two parts of Northwestern France and linkage disequilibrium is higher in Brittany suggesting a lower effective population size. When looking for genomic regions informative about Breton origin, we found two prominent associated regions that include the lactase region and the HLA complex. For both the lactase and the HLA regions, there is a low differentiation between Bretons and Irish, and this is also found at the genome-wide level. At a more refined scale, and within the Pays de la Loire Region, we also found evidence of fine-scale population structure, although principal component analysis showed that individuals from different departments cannot be confidently discriminated. Because of the evidence for fine-scale genetic structure in Western France, we anticipate that rare and geographically localized variants will be identified in future full-sequence analyses.