Rethinking Lethality in Youth Suicide Attempts: First Suicide Attempt Outcomes in Youth Ages 10 to 24.

OBJECTIVE: Although suicide is the second most frequent cause of death in American youth, suicide research has heretofore been confined to convenience samples that represent neither psychiatric nor general populations and that fail to include individuals dying at their first attempts. These limitations were addressed by assembling a youth cohort followed from the first medically recorded attempt (index attempt [IA]). It was hypothesized this approach would more accurately represent the prevalence of completed suicide after an attempt and underscore lethality based on method. METHOD: This study draws from a previously reported retrospective-prospective all-age cohort identified through the Rochester Epidemiology Project. The original 1,490-subject sample included 813 Olmsted County youth 10 to 24 years old (n = 258 male, n = 555 female; 54.6% of total cohort) with IAs from January 1, 1986 through December 31, 2007 and followed until December 31, 2010. RESULTS: Twenty-nine of 813 subjects (3.6%) killed themselves during the study period, with 28 of 29 dying before their 25th birthday and 20 of 28 (71.4%) dying at their first attempt. Despite composing only 31.7% of the cohort (258 of 813), male subjects composed most suicides: 23 of 29 (79.3% of suicides; 8.9% of male subjects) versus 6 of 29 female subjects (20.7% of suicides; 1.1% of female subjects). Eighty-five percent of all IA deaths involved firearms. More than a third of youth-41.2%-lacked a psychiatric history prior to IA. CONCLUSION: These data show that more than half the IAs occurred in youth, with approximately three-fourths of completed youth suicides occurring at the IAs. In parsing cause of IA death in the all-age cohort, the contribution of firearms figured even more prominently in the subsample of youth (85.0%) than in those at least 25 years old (64.3%). The high IA lethality suggests that prevention efforts commencing after the IA are too late for most victims.

Compartmentalization of chemically separated components into droplets.

Not merely a drop in the ocean: The integration of capillary electrophoresis (CE) with droplet generation driven by electroosmotic flow enabled the compartimentalization of molecular components separated by CE in a series of droplets (see picture; the green bars represent the separated analytes). The droplet-confined bands can be docked and studied on a chip.

Capillary electrophoresis separation in the presence of an immiscible boundary for droplet analysis.

This paper demonstrates the ability to use capillary electrophoresis (CE) separation coupled with laser-induced fluorescence for analyzing the contents of single femtoliter-volume aqueous droplets. A single droplet was formed using a T-channel (3 microm wide by 3 microm tall) connected to microinjectors, and then the droplet was fluidically moved to an immiscible boundary that isolates the CE channel (50 microm wide by 50 microm tall) from the droplet generation region. Fusion of the aqueous droplet with the immiscible boundary effectively injects the droplet content into the separation channel. In addition to injecting the contents of droplets, we found aqueous samples can be introduced directly into the separation channel by reversibly penetrating and resealing the immiscible partition. Because droplet generation in channels requires hydrophobic surfaces, we have also investigated the advantages to using all hydrophobic channels versus channel systems with patterned hydrophobic and hydrophilic regions. To fabricate devices with patterned surface chemistry, we have developed a simple strategy based on differential wetting to deposit selectively a hydrophilic polymer (poly(styrenesulfonate)) onto desired regions of the microfluidic chip. Finally, we applied our device to the separation of a simple mixture of fluorescein-labeled amino acids contained within a approximately 10-fL droplet.