Comparison of automated versus traditional nerve conduction study methods for median nerve testing in a general worker population.

OBJECTIVE: To investigate the validity of automated nerve conduction studies compared to traditional electrodiagnostic studies (EDS) for testing median nerve abnormalities in a working population. DESIGN: Agreement study and sensitivity investigation from 2 devices. SETTING: Field research testing laboratory. PARTICIPANTS: Active workers from several industries participating in a longitudinal study of carpal tunnel syndrome. METHODS: Sixty-two subjects received bilateral median and ulnar nerve conduction testing across the wrist with a traditional device and the NC-stat automated device. We compared the intermethod agreement of analogous measurements. MAIN OUTCOME MEASUREMENT: Nerve conduction study parameters. RESULTS: Median motor and sensory latency comparisons showed excellent agreement (intraclass correlation coefficients 0.85 and 0.80, respectively). Areas under the receiver operating characteristic curves were 0.97 and 0.96, respectively, using the optimal thresholds of 4.4-millisecond median motor latency (sensitivity 100%, specificity 86%) and 3.9-millisecond median sensory latency (sensitivity 100%, specificity 87%). Ulnar nerve testing results were less favorable. CONCLUSION: The automated NC-stat device showed excellent agreement with traditional EDS for detecting median nerve conduction abnormalities in a general population of workers, suggesting that this automated nerve conduction device can be used to ascertain research case definitions of carpal tunnel syndrome in population health studies. Further study is needed to determine optimal thresholds for defining median conduction abnormalities in populations that are not seeking clinical care.

Early manipulation of juvenile hormone has sexually dimorphic effects on mature adult behavior in Drosophila melanogaster.

Hormones are critical for the development, maturation, and maintenance of physiological systems; therefore, understanding their involvement during maturation of the brain is important for the elucidation of mechanisms by which adults become behaviorally competent. Changes in exogenous and endogenous factors encountered during sexual maturation can have long lasting effects in mature adults. In this study, we investigated the role of the gonadotropic hormone, juvenile hormone (JH), in the modulation of adult behaviors in Drosophila. Here we utilized methoprene (a synthetic JH analog) and precocene (a JH synthesis inhibitor) to manipulate levels of JH in sexually immature male and female Drosophila with or without decreased synthesis of neuronal dopamine (DA). Locomotion and courtship behavior were assayed once the animals had grown to sexual maturity. The results demonstrate a sexually dimorphic role for JH in the modulation of these centrally controlled behaviors in mature animals that is dependent on the age of the animals assayed, and present DA as a candidate neuronal factor that differentially interacts with JH depending on the sex of the animal. The data also suggest that JH modulates these behaviors through an indirect mechanism. Since gonadotropic hormones and DA interact in mammals to affect brain development and later function, our results suggest that this mechanism for the development of adult behavioral competence may be evolutionarily conserved.