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OBJECTIVE: To study the expression of small ubiquitin-like modifier 1 (SUMO-1) in aseptic loosening of prosthesis implants and to investigate its role in regulating the susceptibility of prosthesis-loosening fibroblast-like synoviocytes (FLS) to Fas-induced apoptosis. METHODS: Specimens of aseptically loosened tissue were obtained at revision surgery, and the expression of SUMO-1 was analyzed by in situ hybridization. SUMO-1 levels in FLS were determined by quantitative polymerase chain reaction and Western blot analysis. Immunohistochemistry and confocal microscopy were used to study the subcellular localization of SUMO-1. The functional role of SUMO-1 in Fas-induced apoptosis of prosthesis-loosening FLS was investigated by small interfering RNA-mediated knockdown of SUMO-1 and by gene transfer of the nuclear SUMO-specific protease SENP1. RESULTS: SUMO-1 was expressed strongly in aseptically loosened tissue and was found prominently at sites adjacent to bone. Prosthesis-loosening FLS expressed levels of SUMO-1 similar to the levels expressed by rheumatoid arthritis (RA) FLS, with SUMO-1 being found mainly in promyelocytic leukemia protein nuclear bodies. Knockdown of SUMO-1 had no effect on spontaneous apoptosis but significantly increased the susceptibility of prosthesis-loosening FLS to Fas-induced apoptosis. Gene transfer of the nuclear SUMO-specific protease SENP1 reverted the apoptosis-inhibiting effects of SUMO-1. CONCLUSION: These data suggest that SUMO-1 is involved in the activation of both RA FLS and prosthesis-loosening FLS by preventing these cells from undergoing apoptosis. Modification of nuclear proteins by SUMO-1 contributes to the antiapoptotic effects of SUMO-1 in prosthesis-loosening FLS, providing evidence for the specific activation of sumoylation during their differentiation. Therefore, SUMO-1 may be an interesting target for novel strategies to prevent aseptic prosthesis loosening. [ABSTRACT FROM AUTHOR]

Seasoned clinical teachers are in short supply and high demand. Although many nursing programs have developed orientation programs for new clinical teachers, many issues arise when students are assigned to health care and community agencies. This study developed and tested the Clinical Teaching Knowledge Test (CTKT), a 40-item multiple-choice test. Items were based on clinical teaching literature and clinical vignettes provided by experienced nursing faculty. A convenience sample (n = 160) of faculty who taught prelicensure students attending baccalaureate programs completed the second version of the test. Proportion correct index, point biserial correlation, and Kuder-Richardson 20 statistics are reported. Proportion correct indexes less than .75 revealed that items testing legal responsibilities to patients, student-faculty relations, counseling approaches, education theory in clinical teaching, students' legal rights, and nursing administrators' rights and responsibilities challenged participants. Results of future testing may help faculty members plan workshops that foster explorations of areas to improve clinical teaching and provide a stimulus for ongoing conversation and reflection about clinical teaching. Additional testing of the CTKT is necessary. Copyright © 2009 by Elsevier Inc. [ABSTRACT FROM AUTHOR]