A non-selective serotonin antagonist promotes rapid habituation in the terrestrial hermit crab.

Research has indicated that serotonin (5-HT) modulates non-associative learning in a variety of invertebrate species. Recent work has demonstrated that the terrestrial hermit crab is a suitable animal model for non-associative learning phenomena, including habituation, sensitization, and dishabituation. We examined the potential role of a non-selective 5-HT antagonist, methysergide, in non-associative learning in the hermit crab. We administered methysergide prior to delivering repeated stimulus presentations of a looming visual predator. We found evidence for more rapid habituation relative to a control condition in which crabs did not receive the drug. These results indicate a role for 5-HT in the defensive behavior of the hermit crab and importantly, suggest a conserved role for 5-HT in modulating basic learning processes in invertebrates.

Expression-Based Cell Lineage Analysis in Drosophila Through a Course-Based Research Experience for Early Undergraduates.

A variety of genetic techniques have been devised to determine cell lineage relationships during tissue development. Some of these systems monitor cell lineages spatially and/or temporally without regard to gene expression by the cells, whereas others correlate gene expression with the lineage under study. The GAL4 Technique for Real-time and Clonal Expression (G-TRACE) system allows for rapid, fluorescent protein-based visualization of both current and past GAL4 expression patterns and is therefore amenable to genome-wide expression-based lineage screens. Here we describe the results from such a screen, performed by undergraduate students of the University of California, Los Angeles (UCLA) Undergraduate Research Consortium for Functional Genomics (URCFG) and high school summer scholars as part of a discovery-based education program. The results of the screen, which reveal novel expression-based lineage patterns within the brain, the imaginal disc epithelia, and the hematopoietic lymph gland, have been compiled into the G-TRACE Expression Database (GED), an online resource for use by the Drosophila research community. The impact of this discovery-based research experience on student learning gains was assessed independently and shown to be greater than that of similar programs conducted elsewhere. Furthermore, students participating in the URCFG showed considerably higher STEM retention rates than UCLA STEM students that did not participate in the URCFG, as well as STEM students nationwide.

A single institution experience in compliance with universal screening for Lynch syndrome in colorectal cancer.

BACKGROUND: Detection of Lynch syndrome has the potential to reduce morbidity and mortality among patients and their family members due to beneficial screening and treatment options. Several institutions have begun to adopt universal rather than risk-stratified screening protocols, but the lack of 100 % compliance rates requires identification of system-level interventions to improve screening practices. OBJECTIVE: We aimed to identify patient, tumor, and system factors associated with lack of screening and identify system-based interventions to improve Lynch syndrome screening. DESIGN AND SETTINGS: This study is a retrospective analysis of Lynch syndrome screening among colorectal cancer patients undergoing surgery in a single healthcare system. PATIENTS: Two hundred and sixty-two patients who underwent surgery for colorectal cancer were studied. MAIN OUTCOME MEASURES: Rate of Lynch syndrome screening. RESULTS: We identified that 75 % of the total cohort was screened for Lynch syndrome. Of patients under the age of 50, 78 % percent were screened. Lower screening rates were found among patients with complete pathologic tumor response and lower pathologic stage of tumor. Higher screening rates were found at the academic hospital and with colorectal surgeons. In multivariable logistic regression analysis, lower screening rates were associated with community hospital location (OR, 0.22; 95 % CI, 0.08-0.56). LIMITATIONS: Results may not be generalizable to different hospital settings. CONCLUSIONS: Several potential system-level interventions were identified to improve screening rates including an emphasis on improved provider communication.