Analysis of testing with multiple choice versus open-ended questions: Outcome-based observations in an anatomy course.

The pedagogical approach for both didactic and laboratory teaching of anatomy has changed in the last 25 years and continues to evolve; however, assessment of student anatomical knowledge has not changed despite the awareness of Bloom's taxonomy. For economic reasons most schools rely on multiple choice questions (MCQ) that test knowledge mastered while competences such as critical thinking and skill development are not typically assessed. In contrast, open-ended question (OEQ) examinations demand knowledge construction and a higher order of thinking, but more time is required from the faculty to score the constructed responses.

Team-based learning in anatomy: an efficient, effective, and economical strategy.

Team-based learning (TBL) strategy is being adopted in medical education to implement interactive small group learning. We have modified classical TBL to fit our curricular needs and approach. Anatomy lectures were replaced with TBL that required preparation of assigned content specific discussion topics (in the text referred as "discussion topics"), an individual self-assessment quiz (IRAT), analysis of the discussion topics, and then the team retaking the same quiz (GRAT) for discussion and deeper learning.

A survey of student perceptions of team-based learning in anatomy curriculum: favorable views unrelated to grades.

Team-based learning (TBL) combines independent out of class preparation with in class small group discussion. We adopted TBL in teaching first year medical gross anatomy. In this study, we evaluated student perceptions of TBL by using a survey that elicited perceptions of both pedagogy and mode of learning.

Modified use of team-based learning for effective delivery of medical gross anatomy and embryology.

Team-based learning (TBL) is an instructional strategy that combines independent out-of-class preparation for in-class discussion in small groups. This approach has been successfully adopted by a number of medical educators. This strategy allowed us to eliminate anatomy lectures and incorporate small-group active learning.

Differential phosphodiesterase activity contributes to restrictive endothelial barrier function during angiogenesis.

Angiogenic endothelial hyperpermeability is abruptly diminished between days 4.5 and 5.0 of the 18-day lifespan of the chick chorioallantoic membrane.

Protein kinase C activity contributes to endothelial hyperpermeability during early angiogenesis in the chick chorioallantoic membrane.

During angiogenesis in the chick chorioallantoic membrane (CAM), microvascular proliferation continues through day 12 of the 18-day CAM lifespan. Up to day 4.5, the neovascularization is associated with endothelial hyperpermeability and differentiation of restrictive barrier function occurs abruptly at day 5.

Vascular endothelial growth factor fails to acutely modulate endothelial permeability during early angiogenesis in the chick chorioallantoic membrane.

The angiogenic endothelium of the chorioallantoic membrane (CAM) offers minimal restriction to macromolecular efflux at Day 4.5 of the normal 21-day chick gestation. Vascular endothelial growth factor (VEGF)-specific Flk-1 and Flt-1 tyrosine phosphorylation was observed at Day 4.

Differentiation of endothelial barrier function during normal angiogenesis requires homotypic VE-cadherin adhesion.

Endothelial cells express two principal cadherins: VE-cadherin and N-cadherin. We established previously that only VE-cadherin expression was increased during differentiation of barrier function by angiogenic endothelium of the chick chorioallantoic membrane (CAM). Presently anti-VE-cadherin mAb, applied to the CAM at day 4.

Cyclic GMP-mediated macromolecular extravasation from angiogenic microvessels in vivo.

Previously, we reported an abrupt reduction in chick chorioallantoic membrane (CAM) microvascular permeability to macromolecules between days 4.5 and 5.0 of the 21-day gestation.

Restrictive endothelial barrier function during normal angiogenesis in vivo: partial dependence on tyrosine dephosphorylation of beta-catenin.

Differentiation of a restrictive endothelial barrier in the chick chorioallantoic membrane (CAM) occurs between Day 4.5 and Day 5.0 of the normal 21-day gestation.

Increased expression of VE-cadherin correlates temporally with differentiation of a restrictive endothelial barrier during normal angiogenesis in vivo.

The purpose of this study was to evaluate temporal expression of VE- and N-cadherins within the angiogenic chick chorioallantoic membrane (CAM). Whether their relative patterns of expression changed in conjunction with abrupt differentiation of the restrictive CAM endothelial barrier between days 4.5 and 5.

Vein interposition cuffs decrease the intimal hyperplastic response of polytetrafluoroethylene bypass grafts.

Purpose: The modification of the distal anastomosis of polytetrafluoroethylene (PTFE) bypass grafts with vein interposition cuffs (VCs) has been reported to increase graft patency. However, the mechanisms that are responsible for this improved patency are unclear. Because intimal hyperplasia (IH) is a primary cause of prosthetic graft failure, we hypothesized that VCs affect the distal anastomosis by decreasing the IH response of the outflow artery.

Dermal tissue fibrosis in patients with chronic venous insufficiency is associated with increased transforming growth factor-beta1 gene expression and protein production.

Purpose: Pathologic dermal degeneration in patients with chronic venous insufficiency (CVI) is characterized by aberrant tissue remodeling that results in stasis dermatitis, tissue fibrosis, and ulcer formation. The cytochemical processes that regulate these events are unclear. Because transforming growth factor-beta(1) (TGF-beta(1)) is a known fibrogenic cytokine, we hypothesized that the increased production of TGF-beta(1) would be associated with CVI disease progression.

Modulation of angiogenic endothelial permselectivity by the cAMP pathway.

The chorioallantoic membrane (CAM) of the chick embryo provides an accessible model of normal angiogenesis in vivo. Previously, we reported a rapid reduction in CAM microvascular permeability to macromolecules between Days 4.5 and 5.

Retinoblastoma protein: a molecular regulator of chronic venous insufficiency.

Purpose: Chronic venous insufficiency (CVI) and varicose vein (VV) formation is characterized histologically by the transformation of smooth muscle cells (SMC) from a contractile to a secretory phenotype and by intense collagen deposition. The subcellular regulation point for these processes may be the retinoblastoma protein (pRb), a known inhibitor of cellular proliferation and regulator of differentiation. We hypothesize that pRb phosphorylation is associated with VV formation and functions as a possible subcellular regulator.

Programmed removal of chondrocytes during endochondral fracture healing.

This investigation tested the hypothesis that the removal of chondrocytes during endochondral fracture healing involves an ordered process of programmed cell death. To accomplish this, unilateral closed fractures were created in the femora of 36 Sprague-Dawley rats. The rats were killed in groups of four on days 1, 3, 7, 14, 21, 28, 42, 49, and 56 after fracture.

Morphometric assessment of the dermal microcirculation in patients with chronic venous insufficiency.

Purpose: Ultrastructural assessments of the dermal microcirculation in patients with chronic venous insufficiency have been limited to qualitative morphologic descriptions of venous ulcer edges or venous stasis dermatitis. The purpose of this investigation was to quantify differences in endothelial cell structure and local cell type with emphasis on leukocytes and their relationship to arterioles, capillaries, and postcapillary venules (PCVs).

Methods: Two 4.

Intraalveolar bubbles and bubble films: III. Vulnerability and preservation in the laboratory.

Background: Having confirmed (Scarpelli et al. 1996. Anat.

Microvascular permselectivity in the chick chorioallantoic membrane during endothelial cell senescence.

The chorioallantoic membrane (CAM) of the chick embryo represents an in vivo model to evaluate microvascular function during the sequential phases of endothelial proliferation (angiogenesis), cytodifferentiation, and senescence. The principal focus of this study was to characterize microvascular barrier functions of the CAM endothelium during its nonproliferating, aging phase (senescence). A graded series of fluorescein isothiocyanate (FITC) dextrans served to index macromolecular selectivity of the senescent capillary endothelium.

Permselectivity of angiogenic microvessels following alteration of the endothelial fiber matrix by oligosaccharides.

The endothelial glycocalyx, which is composed of integral and peripheral glycoconjugates, forms a fibrous matrix that confers macromolecular sieving properties on the microvascular wall. Changes in pore size within the matrix may regulate macromolecular access to the paracellular and/or vesicular transendothelial pathways. We tested the hypothesis that modifications of the endothelial glycocalyx might play a role in the ontogeny of endothelial permselectivity in proliferating microvessels of the chick chorioallantoic membrane (CAM).

Degranulation of mast cells in the chick chorioallantoic membrane does not increase macromolecular extravasation during normal angiogenesis.

Objective: To test the hypothesis that stimulation of mast cell degranulation during normal angiogenesis in the chick chorioallantoic membrane (CAM) serves to acutely activate macromolecular transendonelial pathways.

Methods: Using shell-less cultures of 6-day-old chick embryos, efflux of fluorescein isothiocyanate (FITC)-dextran 150 from CAM microvessels was evaluated, after applications of compound 48/80 or exogenous histamine, by computer-assisted videodensitometric analyses. Real-time confocal imaging enabled optical differentiation of first-order pre- and postcapillaries from the capillary networks.

Mast cell activation accelerates the normal rate of angiogenesis in the chick chorioallantoic membrane.

Using shell-less cultures of chick embryos, the effect of mast cell degranulation on normal rates of angiogenesis in the chorioallantoic membrane (CAM) was recorded from Day 6 to Day 9. Based on the centripetal ordering method with capillaries as the initial point of reference, the first two orders of pre- and postcapillary microvessels were evaluated. After infusion of compound 48/80 into the allantoic cavity, the normal proliferation rate of order-1 pre- and postcapillaries was markedly increased.

Intraalveolar bubbles and bubble films: II. Formation in vivo through adulthood.

Background: Intraalveolar bubbles and bubble films have been shown to be part of the normal alveolar architecture in vivo from birth through the first 2 days of extrauterine life of rabbit pups (Scarpelli et al., 1996a. Anat.

Distribution of anionic sites on microvascular endothelium of the chick chorioallantoic membrane.

It is generally accepted that luminal surfaces of adult microvascular endothelia present an anionic barrier that limits passage of anionic macromolecules. To assess the ontogeny of the barrier, temporal and spatial expression of endothelial anionic sites was evaluated in the chorioallantoic membrane of chicken embryos from days 4.5 to 18 of incubation.