Attentional selectivity,automaticity, and self-efficacy predict simulator-acquired skill transfer to the clinical environment

Introduction

Several studies demonstrated that simulator-acquired skill transfer to the operating room is incomplete. Our objective was to identify trainee characteristics that predict the transfer of simulator-acquired skill to the operating room.

Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations

Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm.     

Biomechanical foot therapy

The podiatrist specializing in biomechanical therapy must begin with a solid foundation of standardized definitions in order to discuss theories of mechanical foot treatment as they have been presented and developed over the past century. Equally important, is the building of a working knowledge and familiarity with the wide variety of available materials and their diverse properties. In addition, in order to arrive at an accurate biomechanical diagnosis, the clinician must evaluate the patient from static, dynamic, and radiographic perspectives. One must also keep current in regard to various technological advances in casting and fabrication of orthotic devices, as well as in new developments in biomechanical theory and associated therapy. It also must be kept in mind that functional foot orthoses are not 100 per cent efficient, therefore, their shape, fabrication, and composition should all be devised and prescribed with specific goals for total body mechanics.     

Functional and phenotypic analysis of tumor-infiltrating lymphocytes isolated from human primary and metastatic liver tumors and cultured in recombinant interleukin-2

Tumor-infiltrating lymphocytes (TIL) were isolated from 40 of 51 consecutive human liver tumor samples (primary hepatocellular carcinoma, 16 of 18; metastatic, 23 of 29; benign, one of four). Functional and phenotypic characteristics of fresh and recombinant interleukin-2 (rIL-2)-expanded TIL were evaluated. The expansion of TIL from hepatic tumors in the presence of 1000 units/ml of rIL-2 was possible in 60% of cases. In comparison to TIL from metastatic liver tumors, TIL obtained from primary liver tumors expanded faster and better in rIL-2 cultures. Expanded TIL from primary tumors had significantly higher cytotoxicity against K562 targets, but not Raji targets, than those from metastatic tumors. Cytotoxicity against fresh autologous tumor targets was detected in seven of eight cultures tested. TIL from primary tumors retained antitumor reactivity significantly longer in culture. The optimal in vitro cytotoxicity was achieved between days 20 and 60 of culture in the presence of rIL-2. Antitumor activity was associated with the increase in these TIL cultures of a cell population expressing the Leu19 antigen with or without the CD3 antigen. The frequency of the CD3+Leu19+ population showed a bimodal distribution during culture: the first peak of CD3+Leu19+ cells occurred between days 30 and 60 and was associated with the increased antitumor activity; the second peak occurred after day 60 and was not associated with activity. These findings demonstrate that TIL from most human hepatic tumors can be successfully isolated, cultured in rIL-2, and enriched in Leu19+ effectors. In addition, these TIL upon IL-2 activation in vitro are capable of lysing fresh autologous and/or allogeneic tumor targets.     

Laboratory evaluation of alignment and kinematics in a unicompartmental knee arthroplasty inserted with intramedullary instrumentation.

The purposes of this study were to evaluate the reliability of intramedullary (IM) instrumentation for unicompartmental total knee replacement and to assess the stability characteristics of the knee after implantation of a relatively unconstrained articular surface. Five adult, human cadaver lower extremities including hip, knee, and ankle were used to evaluate IM alignment. Five adult, fresh-frozen knee specimens were used to evaluate knee kinematics. Long anterioposterior roentgenograms were used to evaluate valgus angle and position of the center of the knee relative to the mechanical axis of the lower extremity. IM instrumentation returned the knee to normal alignment in all cases. The greatest valgus angle change was 3 degrees, and the position of the center of the knee relative to the mechanical axis was not significantly altered. Knee kinematics after unicompartmental knee replacement followed the predicted pattern of normal stability in extension and had slightly less varus-valgus laxity at 30 degrees (p less than 0.01), 45 degrees (p less than 0.01), and 60 degrees (p less than 0.05), and less anteroposterior displacement at 45 degrees (p less than 0.01) and 60 degrees (p less than 0.05). This study offers encouraging evidence that unicompartmental knee replacement with unconstrained components can restore normal knee kinematics, and that alignment can be restored with a high degree of accuracy with an intramedullary alignment system.     

Frequent ongoing T-cell receptor rearrangements in childhood B- precursor acute lymphoblastic leukemia: implications for monitoring minimal residual disease

Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.