The ability to mentally manipulate objects in three dimensions is essential to the practice of many clinical medical specialties. The relationship between this type of visual-spatial ability and performance in preclinical courses such as medical gross anatomy is poorly understood. This study determined if visual-spatial ability is associated with performance on practical examinations, and if students' visual-spatial ability improves during medical gross anatomy. Three hundred and fifty-two first-year medical students completed the Mental Rotations Test (MRT) before the gross anatomy course and 255 at its completion in 2008 and 2009. Hypotheses were tested using logistic regression analysis and Student's t-test. Compared with students in the lowest quartile of the MRT, students who scored in the highest quartile of the MRT were 2.2 [95% confidence interval (CI) 1.2 and 3.8] and 2.1 (95% CI 1.2 and 3.5) times more likely to score greater than 90% on practical examinations and on both practical and written examinations, respectively. MRT scores for males and females increased significantly (P < 0.0001). Measurement of students' pre-existing visual-spatial ability is predictive of performance in medical gross anatomy, and early intervention may be useful for students with low visual-spatial ability on entry to medical school. Participation in medical gross anatomy increases students' visual-spatial ability, although the mechanism for this phenomenon is unknown.

Radiological images show anatomical structures in multiple planes and may be effective for teaching anatomical spatial relationships, something that students often find difficult to master. This study tests the hypotheses that (1) the use of cadaveric computed tomography (CT) scans in the anatomy laboratory is positively associated with performance in the gross anatomy course and (2) dissection of the CT-scanned cadaver is positively associated with performance on this course. One hundred and seventy-nine first-year medical students enrolled in gross anatomy at Boston University School of Medicine were provided with CT scans of four cadavers, and students were given the opportunity to choose whether or not to use these images. The hypotheses were tested using logistic regression analysis adjusting for student demographic characteristics. Students who used the CT scans were more likely to score greater than 90% as an average practical examination score (odds ratio OR 3.6; 95% CI 1.4, 9.2), final course grade (OR 2.6; 95% CI 1.01, 6.8), and on spatial anatomy examination questions (OR 2.4; 95% CI 1.03, 5.6) than were students who did not use the CT scans. There were no differences in performance between students who dissected the scanned cadavers and those who dissected a different cadaver. These results demonstrate that the use of CT scans in medical gross anatomy is predictive of performance in the course and on questions requiring knowledge of anatomical spatial relationships, but it is not necessary to scan the actual cadaver dissected by each student.

By design or default, anatomy educators are often responsible for introducing students to medical professionalism. Although much has been said about the role of anatomical education, there are no published reports suggesting how to measure change. This study investigated what professionalism attitudes, if any, change during a gross anatomy course. Additionally, the influence of four dichotomous variables related to student identity and preparation for medical school were analyzed for their effect on professionalism attitudes. A cross-sectional time-one (T1; beginning of the course), time-two (T2; end of the course) study using the Penn State College of Medicine Survey of Professionalism was conducted. A multivariate analysis of variance identified the main effects and interaction effects of categorical variables. A Mann Whitney U test verified significant differences. This study found a reprioritization of professionalism attitudes in favor of altruism (P = 0.04 with a Cohen's d = 0.26) at T2. Female students (P = 0.03, Cohen's d = 0.38) and students from a science background (P = 0.04, Cohen's d = 0.36) changed the most in favor of altruism. Interestingly, though several factors correlated with dissimilarities in professionalism values at T1, gender was the only factor to show a significant difference in professionalism attitudes at T2. This cohort of students reported a statistically significant increase in altruism and no significant decreases in other professionalism attitudes concurrent with the gross anatomy course.

The objectives of this study were (1) to measure plasma (V(p)), blood (V(b)), extracellular (V(e)), and interstitial fluid (V(ist)) volumes using the same techniques; (2) to measure the rate of plasma turnover; and (3) to characterize the three important variables required to interpret transvascular flux at an organismal level (vascular compliance [C(vas)], interstitial compliance [C(ist)], and the whole-body transvascular filtration coefficient [F(c)]) in two species of anurans that differ in their capacity to regulate blood volume during dehydrational and hemorrhagic stress. The disappearance curve of Evans blue-labeled native plasma protein fitted a two-component exponential decay model for both species, indicating that plasma proteins exchanged quickly between two kinetically distinct compartments, V(p) and V(e). V(p) calculated using serial sampling times <10 min were 61.0 mL kg(-1) for Chaunus marinus and 40.5 mL kg(-1) for Lithobates catesbeiana. Plasma turnover rate was 3% of V(p) min(-1) (1.8 mL min(-1) kg(-1)) for C. marinus and 5.5% of V(p) min(-1) (2.2 mL min(-1) kg(-1)) for L. catesbeiana. Chaunus marinus also had significantly greater V(b) (84 to 53 mL kg(-1)), V(ist) (171 to 154 mL kg(-1)), and V(e) (232 to 195 mL kg(-1)) than L. catesbeiana. C(vas) was significantly greater in C. marinus (47.3 mL kPa(-1) kg(-1)) compared with L. catesbeiana (27.7 mL kPa(-1) kg(-1)). This difference reflects the interspecific differences in V(b) because vascular distensibilities are similar (0.5% kPa(-1)). There were no interspecific differences in the C(ist) (500 mL kPa(-1) kg(-1)) or F(c) (2.5 mL kg(-1) kPa(-1) min(-1) filtration calculation; 0.2-0.5 mL kPa(-1) kg(-1) min(-1) fit to volume change data). Functionally, these circulatory/interstitial exchange variables of both anuran species exemplify a circulatory system with high rates of filtration (lymph formation) and with no capacity for transcapillary fluid uptake, hence requiring substantial lymphatic return to maintain vascular volume. The large C(ist) of both species provides a capacity to store extravascular volume with little perturbation of vascular pressure, but the resulting low interstitial pressures would create difficulties for extravascular fluid return to the dorsally located lymph hearts. The principal interspecific differences of greater V(b), V(p), V(ist), and C(vas) for the more terrestrial species, C. marinus, would stabilize cardiac function during hypovolemia (e.g., hemorrhage) and increase resistance to dehydration. This is consistent with this species' enhanced capacity to manage dehydrational and hemorrhagic challenges to blood volume regulation compared to L. catesbeiana.

The cardiovascular effects of endothelin (ET)-1 and the recently sequenced homologous trout ET were examined in unanesthetized trout, and vascular capacitance curves were constructed to evaluate the responsiveness of the venous system to ET-1. A bolus dose of 667 pmol/kg ET-1 doubled ventral aortic pressure; produced a triphasic pressor-depressor-pressor response in dorsal aortic pressure (P(DA)); increased central venous pressure, gill resistance, and systemic resistance; and decreased cardiac output, heart rate, and stroke volume. These responses were dose dependent. Bolus injection of trout ET (333 or 1,000 pmol/kg) produced essentially identical, dose-dependent cardiovascular responses as ET-1. Dorsal aortic infusion of 1 and 3 pmol. kg(-1). min(-1) ET-1 and central venous infusion into the ductus Cuvier of 0.3 and 1 pmol. kg(-1). min(-1) produced similar dose-dependent cardiovascular responses, although the increase in P(DA) became monophasic. The heightened sensitivity to central venous infusion was presumably due to the more immediate exposure of the branchial vasculature to the peptide. Infusion of 1 pmol. kg(-1). min(-1) ET-1 decreased vascular compliance but had no effect on unstressed blood volume. These results show that ETs affect a variety of cardiovascular functions in trout and that branchial vascular resistance and venous compliance are especially sensitive. The multiplicity of effectors stimulated by ET suggests that this peptide was extensively integrated into cardiovascular function early on in vertebrate phylogeny.