Assessment in Basic Science Instruction: Directions for Practice and Research

In this essay, we discuss assessment of students' understanding of the basic biomedical sciences during the basic science component of medical education. Because we strongly believe that assessment should follow from and be congruent with course and curricular goals, the first section discusses recent trends in basic science education: where it's been and where it appears to be headed. The second section discusses considerations in the design of an assessment system that reflects curricular goals and encourages students to achieve them; it also identifies some research issues that we think merit attention. In the last section, we outline some of the special assessment issues and problems that arise in the context of problem-based learning (PBL) and discuss the merits of some of these novel assessment approaches, as well as the use of more traditional methods in PBL curricula.This revised version was published online in September 2005 with corrections to the Cover Date.     

"Stockless" cost reduction in the operating room

St. Paul-Ramsey Medical Center in St. Paul, MN became one of the first hospitals in the United States to initiate a "stockless" par level inventory system. Successes with stockless led the hospital to look at implementing it in the OR to achieve a reduction of expense to revenue. Materiel Management and Surgical Services discussed a number of issues relevant to implementing a stockless program, including product flow, accuracy and cost of case carts and preference cards, item pricing, committed usage of items brought into the system and establishment of a steering committee. Specific OR issues and practices required evaluation and adjustment, such as the routine use of emergency direct ordering. Information systems support was brought in and a products committee established to do education and oversee the program. Savings for 1993-94 were $185,146.     

DUEs for the '90s: multicentered, outcome-oriented

The likely development of healthcare alliances and affiliations will create a logical role for multicentered DUEs that study treatment regimens or indications in a healthcare system made up of several institutions. Such a study is under way in New Jersey, involving 15 hospitals. The DUE is evaluating usage patterns of ticarcillin/clavulanate and two other broad-spectrum antibiotics. A multicenter DUE presents challenges, such as the need for additional resources and for consensus among disparate elements; but this methodology also opens up expanded roles for pharmacists, including participation in quality assurance activities.     

Effect of Percoll wash on sperm motion parameters and subsequent fertility in intrauterine insemination cycles

Purpose This study examined sperm motion parameters as measured by computerized automated semen analysis before and after a Percoll wash and determined if differences in any parameter were correlated with fertility subsequent to intrauterine insemination (IUI).Results Total motile sperm decreased following the washing procedure from 79.0 ± 9.0 to 37.2 ± 7.6 million sperm. Motility increased from a mean of 43.4% to 61.7% (P<0.001). Other motility parameters also changed significantly (P<0.001) as follows: curvilinear velocity (VCL), 43.4 to 61.7 m/s; straight-line velocity (VSL), 21.3 to 26.7 m/s; linearity 53.1 to 45.2%; lateral head displacement (ALH), 2.97 to 3.94 m. Similar changes occurred following a swim-up preparation, although changes in mean motility, VCL, and ALH were significantly greater when compared to Percoll. The postwash changes were not accounted for merely by time lapse in preparation since reanalyzed untreated controls did not show the same changes in motion parameters. Prewash linearity in those specimens which resulted in pregnancies was greater than in those which did not (P=0.28). No other significant differences in pre-or post-Percoll washed sperm motion parameters were found between pregnant vs nonfertile cycles.Conclusion Following Percoll wash all CASA-generated motility parameters were significantly altered, but there was little association between these parameters and pregnancy achieved in IUI cycles.Presented at the 50th Annual Meeting of the American Fertility Society, San Antonio, Texas, November 5–10, 1994.     

Excitatory amino acid release from astrocytes during energy failure by reversal of sodium-dependent uptake

Non-synaptic release may be the major route of excitatory amino acid (EAA) efflux during cerebral ischemia. Possible routes of non-synaptic release include non-specific anion channels, reversal of Na⁺-, CI^?-, or Ca²⁺-dependent uptake, and cell lysis. In the present study we employ a novel approach to show reversal of Na⁺-dependent uptake as a major route of EAA efflux from astrocyte cultures under conditions of energy failure. Primary rat astrocyte cultures were subjected to combined blockade of glycolytic and oxidative metabolism after incubation with [³H]-D-aspartate (D-ASP). Energy failure produced an efflux of D-ASP that was maximal by 90 minutes. The efflux over this period was reduced by more than 50% in cells that had been pre-loaded with PDC (L-transpyrrolidine-2,4-dicarboxylic acid) or TBHA (threo-β-hydroxyaspartic acid), compounds that are competitive inhibitors of Na⁺-dependent glutamate uptake. The effect of pre-loading with the inhibitors was concentration dependent. No effect was seen if the inhibitors were added after induction of energy failure, suggesting that the attenuation of D-ASP efflux resulted from binding of the inhibitors to an intracellular site. These results provide strong evidence that EAA efflux from astrocytes under conditions of energy failure occurs largely through reversal of Na⁺-dependent uptake. © 1995 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Enhancement of benzo(a)pyrene metabolism mediated by retinol acetate in cultured human bronchial epithelial-cells

As suggested by animal studies and human epidemiological data, retinoids possess significant cancer chemopreventive activity. Although the majority of studies in this area have focused on the ability of retinoids to prevent the promotion or progression of carcinogenesis, a significant amount of data suggest retinoids can alter initiation events. In the current report, we have evaluated the potential of retinol acetate to modulate benzo(a)pyrene metabolism in low-passage human bronchial epithelial cells in monolayer cultures, Of 16 different cell cultures, benzo(a)pyrene metabolism was increased in 14, decreased in one, and unchanged in one, when retinol acetate was added to the media, In a preliminary study with one of the cell cultures in which retinol acetate significantly enhanced benzo(a)pyrene metabolism, binding of carcinogen metabolites to;DNA was unaffected, Since retinoids are known cancer chemopreventive agents and carcinogen binding to DNA is the key event in the initiation of carcinogenesis, these results suggest that retinoids may decrease carcinogenic risk by increasing the detoxification of procarcinogens such as benzo(a)pyrene ina manner that does not yield a concomitant increase in damage to critical cellular targets such as DNA.     

Review of animal models in carotenoid research

Foods containing provitamin A carotenoids are the primary source of vitamin A in many countries, despite the poor bioavailability of carotenoids. In addition, epidemiologic studies suggest that dietary intake of carotenoids influences the risk for certain types of cancer, cardiovascular disease and other chronic diseases. Although it would be ideal to use humans directly to answer critical questions regarding carotenoid absorption, metabolism and effects on disease progression, appropriate animal models offer many advantages. This paper will review recent progress in the development of animal models with which to study this class of nutrients. Each potential model has strengths and weaknesses. Like humans, gerbils, ferrets and preruminant calves all absorb beta-carotene (betaC) intact, but only gerbils and calves convert betaC to vitamin A with efficiency similar to that of humans. Mice and rats efficiently convert betaC to vitamin A but absorb carotenoids intact only when they are provided in the diet at supraphysiologic levels. Mice, rats and ferrets can be used to study cancer, whereas primates and gerbils are probably more appropriate for studies on biomarkers of heart disease. No one animal model completely mimics human absorption and metabolism of carotenoids; thus the best model must be chosen with consideration of the specific application being studied, characteristics of the model, and the available funding and facilities.     

Information technology and under-served communities

Advances in information technology (IT) and telecommunications offer many potential benefits to Australia's under-served communities. However, there is also a risk that some of these communities will only be further disadvantaged, as IT will not contribute greatly to bringing groups such as the mentally ill and illiterate into the mainstream of the community. However, other under-served groups may experience service improvements. For people who do not have English as their first language, IT developments provide opportunities for cheaper and easier service and information delivery in their own languages. Telemedicine and IT also have the potential to make working in rural areas more attractive. On the other hand, telemedicine may be used as a means to bypass local health service providers, as has happened with other service industries. The health sector, though, is well behind these other industries in adopting IT and telecommunications. The growth of telemedicine projects is one indication that progress is being made, however. Two case studies--of telepsychiatry, and of medical education at Flinders University--provide examples of major Australian successes. The medical workforce implications will involve the overall numbers and mix of practitioners, their geographical distribution, changing professional boundaries and changing skill requirements. The only certain effect is that if IT changes the nature of medical work, large numbers of medical practitioners will need to improve their computer skills and older practitioners will find this most difficult.