Vicarious,direct, and imaginal aversion in habit control: Outcomes,heart rates,and subjective perceptions

Direct, modeled, or imaginal shocks administered by therapist or recipient were compared as aversion techniques for 60 women college students with severe nail-biting habits. All methods increased habit control (p <.001)on self-report and objective measures but with no outcome differences among treatments. Providing mental rehearsal guidance for extralaboratory use failed to alter outcome but raised client optimism to ward therapy. Vicarious aversion produced the most rapid heart rates and, typically, the greatest subjective arousal; no data suggested that direct shock was superior. In a second study with unselected student volunteers of both sexes, modeled shock consistently surpassed imaginal shock in ratings of perceived badness, subjective discomfort, and vividness of covert pain (p <.01).Treatment and ethical implications were discussed. We are indebted to Lisa Obstfeld, who performed ably as the long-suffering model, and to Albert Bandura, Mary Gabrielson, Glenn M. White, and Louis Zimmer, who assisted with other matters. Part of this research was completed while all authors were at the University of Arizona, Tucson.     

Head-to-head comparison of B-type natriuretic peptide (BNP) and NT-proBNP in daily clinical practice

B-type natriuretic peptide (BNP; Abbott Diagnostics) and N-terminal proBNP (NT-proBNP, Roche Diagnostics) were compared in consecutive samples of 458 patients (mean age 60 years+/-16 years; 159 female, 299 male) sent for NT-proBNP measurement to investigate influences on both markers. BNP and NT-proBNP showed a close correlation with each other (r=0.89, p<0.0001). Using age- and gender-adjusted upper reference values the inter-rater agreement of both parameters was satisfactory (83%, Cohen's kappa coefficient=0.7). The combination of normal BNP and elevated NT-proBNP was significantly more frequent than vice versa (61 vs. 16 patients), and a calculated glomerular filtration rate<60 ml/min/1.73 m(2) was found in 39% of these patients. Multiple linear regression analysis revealed a significant influence of a reduced ejection fraction (<50%), renal dysfunction (calculated glomerular filtration rate<60 ml/min/1.73 m(2)), anemia, hypertension, age, and gender on both BNP and NT-proBNP. In conclusion, despite a close correlation and a satisfactory agreement between both markers in classification, frequent discrepancies in individual patients demonstrate that both markers are clinically not completely equivalent.     

Mixed functional characteristics correlating with TCR‐ligand koff‐rate of MHC‐tetramer reactive T cells within the naive T‐cell repertoire

The low frequency of antigen‐specific naïve T cells has challenged numerous laboratories to develop various techniques to study the naïve T‐cell repertoire. Here, we combine the generation of naïve repertoire‐derived antigen‐specific T‐cell lines based on MHC‐tetramer staining and magnetic‐bead enrichment with in‐depth functional assessment of the isolated T cells. Cytomegalovirus (CMV) specific T‐cell lines were generated from seronegative individuals. Generated T‐cell lines consisted of a variety of immunodominant CMV‐epitope‐specific oligoclonal T‐cell populations restricted to various HLA‐molecules (HLA‐A1, A2, B7, B8, and B40), and the functional and structural avidity of the CMV‐specific T cells was studied. Although all CMV‐specific T cells were isolated based on their reactivity toward a specific peptide‐MHC complex, we observed a large variation in the functional avidity of the MHC‐tetramer positive T‐cell populations, which correlated with the structural avidity measured by the recently developed Streptamer k_off‐rate assay. Our data demonstrate that MHC‐tetramer staining is not always predictive for specific T‐cell reactivity, and challenge the sole use of MHC‐tetramers as an indication of the peripheral T‐cell repertoire, independent of the analysis of functional activity or structural avidity parameters.