Development of online conferencing and web-based in-service modules for preceptor training.

Over the past five years our clinical laboratory sciences (CLS) program more than doubled student enrollment to help address the workforce shortages in our state. At the same time, medical laboratory technician programs were also increasing enrollment, putting significant pressure on the already limited number of clinical training spaces. To help alleviate the impact on clinical sites, major changes were made to the traditional clinical rotation model; shifting from a clinical training to a clinical experience and a simultaneous decrease in length from 22 to 12 weeks. This change required extensive in-service training for clinical preceptors including rationale for the new clinical experience model, review of student campus education, expectations for preceptors and students, as well as developing and implementing new evaluation methods of student performance. Through funding from the Department of Labor, online interactive modules introducing the concepts of new clinical experience module for both preceptors and for students were developed. To provide a more in-depth and specific in-service for the preceptors, web-conferences were held to describe the students' didactic and laboratory educational background and to discuss the expectations and evaluations of students. Two course management system sites were developed, one for preceptors and one for students, so they could access clinical experience information and materials at any time and from any location. These course sites also allowed us to convert evaluation processes to an online format. Survey feedback from preceptors indicates that this system was well received providing a cost-effective method for preceptor education and communication.

Graduate education in clinical laboratory science is the glass half full or half empty?

OBJECTIVE: To evaluate the 2007 and 1990 data on the number and characteristics of programs offering graduate level degrees in Clinical Laboratory Science. DESIGN/SETTING/PARTICIPANT: Data were collected from published sources (Directory of Graduate Programs for Clinical Laboratory Practitioners) and analyzed at the University of Minnesota. Specific data regarding the kinds of advanced programs and the number of graduates per year, the number of program openings and closures, program requirements were collected, as well as data regarding the number and employment of graduates of Master's degree programs at two long-standing public institutions. INTERVENTION: Not Applicable. MAIN OUTCOME MEASURE: The tabulation of degree, program, and graduate data, together with the first position taken by graduates of two M.S. programs. RESULTS: The numbers of graduate level programs and graduates decreased between 1990 and 2007, from 39 to 28 identified Master's level programs, but with only a slight increase from two to five doctoral programs. Several prominent and historically important Master's level programs have closed since the first edition (1990) of the Directory. Detailed analysis of the data from two Master's level programs showed that the first positions for graduating students were predominantly research related and in the same state as the degree-granting institution. CONCLUSION: The number of advanced programs and graduates are relatively small in clinical laboratory science; however M.S. graduates are successful in obtaining positions. These positions are predominantly geographically related to the degree-granting institution, indicating an intellectual and economic impact of the programs in the regions they are located.

Molecular modeling of the calmodulin binding region of calcineurin.

The Homology module within Insight-II was used to model residues 374-420, sequences missing in the coordinates of resolved structure of the catalytic subunit of calcineurin. The modeling was done in two segments. The calmodulin binding region from residues 389 to 420 was modeled based on the structure of two other proteins having calmodulin binding domains with the same 1-8-14 structural motif as calcineurin. The link region (residues 374-389) between the calmodulin binding region and the solved core sequence was generated as a random loop and two residues at the C-terminal end of the sequence were added to the model using the EndRepair function within Homology. The model was refined using the Discover module of Insight-II with energy minimization. The Builder module was used to merge the modeled regions with the solved structure of calcineurin (residues 14-373). A final refinement step was done for the joined calcineurin model. From the model, it was predicted that the calmodulin and cyclophilin binding regions seem to be proximal. Biochemical experiments provided evidence that cyclosporin-A influenced calmodulin binding and activation of calcineurin consistent with overlapping binding regions.

Evidence for the Cd(2+) activation of the aryl sulfatase from helix pomatia.

Often used to remove sulfate groups from carbohydrates, the regulatory properties of the aryl sulfatase from Helix pomatia remain little characterized. As many hydrolytic enzymes utilize exogenous metal ions in catalysis, the effect of various divalent metal ions on the sulfatase was investigated. Evidence for metal ion activation was collected, with Cd(2+) being notable for effective activation. The enzyme was inhibited by Cu(2+). The response of other common hydrolases to divalent metal ions was characterized. Activation by Cd(2+) was not observed for chymotrypsin, rabbit liver esterase, or beta-galactosidase. Instead, Cd was found to inhibit both the esterase and the galactosidase. Inhibition by Cu(2+) and Zn(2+) was also observed for some of these hydrolases.

Calcineurin hydrolysis of para-nitrophenyl phosphorothioate.

para-Nitrophenyl phosphorothioate (pNPT) was hydrolyzed by calcineurin at initial rates slightly, but comparable to rates for para-nitrophenyl phosphate (pNPP). Kinetic characterization yielded higher estimates for both Km and Vmax compared to pNPP. Metal ion activation of phosphorothioate hydrolysis was more promiscuous. Unlike the hydrolysis of with pNPP, Ca2+, Mg2+, and Ba2+ activated calcineurin as well as Mn2+.

Response of recombinant calcineurin to metal ions, reduction-oxidation agents, and enzymatic modification.

Recombinant calcineurin heterodimer with the full length delta-isoform of the catalytic subunit (CaN(500)) was expressed in insect cells using the baculovirus system and compared to native bovine brain enzyme in its response to divalent metal ions, redox reagents, and enzymatic modification of arginine residues. The response to various metal ions showed essentially the same profile as bovine brain calcineurin, although Co2+ and Zn2+ did not support recombinant activity as well. Kinetic analysis showed that metal ion and substrate binding were not independent, as found for the bovine brain calcineurin. Incubation with DTT or ascorbate alone caused similar effects on the activity of both enzymes, but different responses were observed when incubated with both DTT and ascorbate; only the recombinant enzyme showed activation. Arginine deimination of recombinant calcineurin by peptidylarginine deiminase resulted in the loss of 60-80% of its phosphatase activity with protection observed if calmodulin was present. Recombinant calcineurin was reactivated by treatment with the protease clostripain, suggesting that deimination of an arginine in the carboxyl terminal domain may be responsible for the loss of phosphatase activity and decreased calmodulin binding [Arch. Biochem. Biophys. 318 (1995) 370]. Supporting this conclusion, a truncated variant of the catalytic subunit lacking the carboxyl terminus showed no loss of phosphatase activity compared to full length calcineurin subunit and contained lower amounts of citrulline than the full length subunit after deimination. These different responses of recombinant calcineurin are consistent with conformational differences compared to bovine brain calcineurin and raise questions about its utility for studying the mechanism of calcineurin.