Multi-institutional study of self-reported attitudes and behaviors of general surgery residents about ethical academic practices in test taking.

PURPOSE: Correlation exists between people who engage in academic dishonesty as students and unethical behavior once in practice. Previously, we assessed the attitudes of general surgery residents and ethical practices in test taking at a single institution. Most residents had not participated in activities they felt were unethical, yet what constituted unethical behavior was unclear. We sought to verify these results in a multi-institutional study. METHODS: A scenario-based survey describing potentially unethical activities related to the American Board of Surgery In-training Examination (ABSITE) was administered. Participants were asked about their knowledge of or participation in the activities and whether the activity was unethical. Program directors were surveyed about the use of ABSITE results for resident evaluation and promotion. RESULTS: Ten programs participated in the study. The resident response rate was 67% (186/277). Of the respondents, 43% felt that memorizing questions to study for future examinations was unethical and 50% felt that using questions another resident memorized was unethical. Most felt that buying (86%) or selling (79%) questions was unethical. Significantly more senior than junior residents have memorized (30% vs 16%; p = 0.04) or used questions others memorized (33% vs 12%; p = 0.002) to study for future ABSITE examinations and know of other residents who have done so (42% vs 20%; p = 0.004). Most programs used results of the ABSITE in promotion (80%) and set minimum score expectations and consequences (70%). CONCLUSION: Similar to our single-institution study, residents had not participated in activities they felt to be unethical; however the definition of what constitutes cheating remains unclear. Differences were identified between senior and junior residents with regard to memorizing questions for study. Cheating and unethical behavior is not always clear to the learner and represents an area for further education.

Laser capture microdissection of cells from plant tissues.

Laser capture microdissection (LCM) is a technique by which individual cells can be harvested from tissue sections while they are viewed under the microscope, by tacking selected cells to an adhesive film with a laser beam. Harvested cells can provide DNA, RNA, and protein for the profiling of genomic characteristics, gene expression, and protein spectra from individual cell types. We have optimized LCM for a variety of plant tissues and species, permitting the harvesting of cells from paraffin sections that maintain histological detail. We show that RNA can be extracted from LCM-harvested plant cells in amount and quality that are sufficient for the comparison of RNAs among individual cell types. The linear amplification of LCM-captured RNA should permit the expression profiling of plant cell types.

Distinct but conserved functions for two chloroplastic NADP-malic enzyme isoforms in C3 and C4 Flaveria species.

In the most common C4 pathway for carbon fixation, an NADP-malic enzyme (NADP-ME) decarboxylates malate in the chloroplasts of bundle sheath cells. Isoforms of plastidic NADP-ME are encoded by two genes in all species of Flaveria, including C3, C3-C4 intermediate, and C4 types. However, only one of these genes, ChlMe1, encodes the enzyme that functions in the C4 pathway. We compared the expression patterns of the ChlMe1 and ChlMe2 genes in developing leaves of Flaveria pringlei (C3) and Flaveria trinervia (C4) and in transgenic Flaveria bidentis (C4). ChlMe1 expression in C4 species increases in leaves with high C4 pathway activity. In the C3 species F. pringlei, ChlMe1 expression is transient and limited to early leaf development. In contrast, ChlMe2 is expressed in C3 and C4 species concurrent with stages in chloroplast biogenesis. Because previous studies suggest that NADP-ME activities generally reflect the level of its mRNA abundance, we discuss possible roles of ChlMe1 and ChlMe2 based on these expression patterns.

Differential regulation of transcripts encoding cytosolic NADP-malic enzyme in C3 and C4 Flaveria species.

A cytosolic NADP-malic enzyme (CYTME) has been described previously in several plants, all C3 species. CYTME is distinct from the chloroplastic NADP-malic enzyme (CHLME) that is highly active in C4 species. We show that at least one CytMe gene is present in all Flaveria spp., including C3, C4, and C3-C4 intermediate types. Based on the CytMe expression patterns in Flaveria pringlei (C3) and Flaveria trinervia (C4), we suggest CYTME has several distinct roles, including the supplying of NADPH for cytosolic metabolism, the supporting of wound response or repair, and the balancing of cellular pH in illuminated leaves. These three roles are likely correlated with CytMe mRNAs of apparent sizes 2.0, 2.2, and 2.4 kb, respectively, which differ in the length of the 5' untranslated regions. Various regulatory mechanisms involving RNA processing and translational efficiency are discussed.