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Purpose: To describe sources of interindividual variability in bevacizumab disposition in pediatric patients and explore associations among bevacizumab pharmacokinetics and clinical wound healing outcomes.Experimental Design: Before tumor resection, three doses of bevacizumab (15 mg/kg) were administered to patients (median age, 12.2 years) enrolled in a multi-institutional osteosarcoma trial. Serial sampling for bevacizumab pharmacokinetics was obtained from 27 patients. A population pharmacokinetic model was fit to the data, and patient demographics and clinical chemistry values were systematically tested as predictive covariates on model parameters. Associations between bevacizumab exposure and wound healing status were evaluated by logistic regression.Results: Bevacizumab concentration–time data were adequately described by a two-compartment model. Pharmacokinetic parameter estimates were similar to those previously reported in adults, with a long median (range) terminal half-life of 12.2 days (8.6 to 32.4 days) and a volume of distribution indicating confinement primarily to the vascular space, 49.1 mL/kg (27.1 to 68.3 mL/kg). Body composition was a key determinant of bevacizumab exposure, as body mass index percentile was significantly (P < 0.05) correlated to body-weight normalized clearance and volume of distribution. Furthermore, bevacizumab exposure before primary tumor resection was associated with increased risk of major wound healing complications after surgery (P < 0.05).Conclusion: A population pharmacokinetic model for bevacizumab was developed, which demonstrated that variability in bevacizumab exposure using weight-based dosing is related to body composition. Bevacizumab dosage scaling using ideal body weight would provide an improved dosing approach in children by minimizing pharmacokinetic variability and reducing likelihood of major wound healing complications. Clin Cancer Res; 20(10); 2783–92. ©2014 AACR.

PDF file - 200K, Supplementary Table 1. Comparison of predictive performance for model parameterizations A, (B), and C (with IBW covariate) Supplemental Figure 1. The base structural bevacizumab model consisted of a two compartment model parameterized in terms of clearance from the central compartment and intercompartmental transfer to and from central and peripheral compartments. Supplemental Figure 2. Observed concentration-time data (filled diamonds) with simulations from individual posthoc parameter estimates (dashed lines; ~2 hrs step size) indicate that bevacizumab exhibits bi-exponential decay with a relatively rapid alpha phase and a prolonged beta terminal phase. Supplemental Figure 3. Visual predictive check of observed and model-predicted serum bevacizumab concentrations following 15 mg/kg dosing over a course of three occasions. The shaded region represents the 95% confidence interval of the Monte Carlo model simulations.

In recent years, substantial resources have been invested in researching and describing the enactment of “core practices” of teaching in teacher education. This review of the literature examined more than 40 articles published between 2008 and August 2018 in an effort to determine how teacher educators are supporting teacher candidates to learn about and enact core practices of teaching. The review of the literature presented here demonstrates two distinct approaches that teacher educators use to introduce and prepare teacher candidates to enact core practices: a predesigned enactment approach and an open-design enactment approach. Our goal in identifying these two approaches is to illuminate the role and actions of teacher educators in core-practice work and to demonstrate that the decisions teacher educators make in core-practice work are complex and nuanced, and require further description than heretofore available.

Often principals in urban school districts report to a central office staff person whose primary function is to supervise principals. Over the past decade, the principal supervisor role has shifted away from administrative oversight toward developing principals’ instructional leadership capacity. As principals are increasingly responsible for driving improvement in their schools, the demands of supervising principals similarly have changed. This chapter examines the ways in which principal supervisors developed and supported principals’ instructional leadership analyzing over 200 interviews collected in 6 urban school districts that participated in the Principal Supervisor Initiative. These districts shifted principal supervision from a traditional administrative oversight model to one focused on principal development and support. The chapter describes the activities, practices, and routines that grounded the work of principals and their supervisors, and demonstrates the importance of supervisors’ own learning to develop the skills necessary to carry out the new role and build consistency of practice.

The purpose of this study was to investigate the ways novice social studies teachers perceived difficult discourses in their classrooms. Specifically, we sought to understand what social studies teachers think is difficult about navigating political discourses, and how they describe the nature of those discourses in order to draw conclusions about why some teachers choose to avoid or engage in political or social issues discussions with students. We used a collective case study and a grounded theory analysis of video recorded class sessions and video guided debriefings with teachers to explore this phenomena. We found that the degree to which teachers thought the discourse to be difficult to navigate was shaped by: emotional safety of students, teacher's own ideologies, and the distances of students’ identities from the discourse.

PurposeIn both elementary schools and elementary teacher education programs, social studies is marginalized while standards require increasingly more ambitious reasoning, reading, and writing in social studies than has historically been documented in American elementary schools. The purpose of this paper is to explain the challenges that elementary social studies teacher educators face in preparing elementary school teachers to facilitate the kind of ambitious social studies envisioned in the NCSS’s C3 Framework and advocate an approach to successfully address these challenges.Design/methodology/approachThis paper articulates a targeted and ambitious approach to elementary social studies teacher education. The authors describe five recommendations from the teacher education literature for supporting preservice teachers in learning disciplinary-oriented social studies teaching, recommendations that guided the redesign of the social studies methods course. The authors then highlight key aspects of the redesigned methods course and demonstrate how the authors engaged the challenges inherent in the work of elementary social studies teacher education.FindingsAlthough this paper is not arranged in such a way as to substantiate empirical findings, the purpose of the paper is to demonstrate an approach to elementary social studies education aligned with extant literature on preparing teachers to engage in reform teaching practices, specifically those disciplinary oriented practices suggested in NCSS’s C3 Framework. As such, the paper should be read as a perspective on practice.Research limitations/implicationsThe type of disciplinary-oriented approach described here is increasingly under investigation in secondary teacher education research and similar approaches are under investigation in elementary math and science education research. To the authors’ knowledge, the approach is novel in elementary social studies education. Furthermore, the authors believe it offers a direction for researchers interested in gaps in the literature related to practice based teacher education and disciplinary-oriented social studies teacher education.Practical implicationsThe approach described here offers specific guidance and resources for teacher educators who are struggling with the challenges of the contemporary social studies education landscape and/or who wish to focus methods courses in disciplinary ways.Social implicationsResearch in social studied education has demonstrated that when students are exposed to disciplinary practices in social studies, their literacy skills improve and they learn analytical skills that support their development as citizens (consumption of media, participation in public discourse, ability to discern arguments).Originality/valueAs noted above, the approach described here is novel in elementary social studies education. Combining a disciplinary approach with a practice-based frame in elementary social studies represents an opportunity for empirical research and offers new approaches to the practice of teacher education and early career professional development.

Recently, scholars have called for a practice-based framework for teacher education and some have argued more narrowly for a framework built around ‘core practices of teaching.’ These efforts, in part, are intended to make teacher education practice public and available for collective improvement. The purpose of this paper is to highlight challenges and possibilities that arose during a core practice-oriented course redesign. Despite attention to the literature, the teacher educators faced dozens of inherent tensions and contextual challenges that distinguish their understanding of core practices from other teacher educators operating with common principles. Based on lessons learned, the author argues for greater attention to the details of core practice redesigns, rationales explaining redesign decisions, and empirical investigation of teacher candidate outcomes of such redesigned courses and programs.

Vascular injury has been reported in up to one third of patients with posterior knee dislocations, which has led to the routine use of arteriograms in the management of these injuries. Recent studies have shown physical examination (PE) is reliable in detecting significant vascular injuries requiring surgery from other mechanisms. We hypothesized that PE would be similarly sufficient to assess popliteal injury in patients with posterior knee dislocations. To test this, we reviewed the records of all 37 patients with 38 such injuries at our institution over the past 5 years. The average age was 29.5 years, and 31 patients (81.5%) had other associated injuries. All dislocations were the result of blunt trauma. Two patients (5.3%) had hard signs (distal ischemia and no pulses) that clearly indicated vascular injury. Total occlusions of the popliteal artery were seen on arteriograms in both cases and these were successfully treated surgically with reversed saphenous vein bypass grafts. The remaining 36 dislocations manifested no hard signs of vascular injury (absent pulses, distal ischemia, active bleeding, bruit/thrill). Nineteen patients (50.0%) had normal vascular examination results, did not receive arteriograms, and had no adverse sequelae, with a mean follow-up of 9.3 months (range 1 day-43 months). Sixteen patients with 17 dislocations (44.7%) underwent arteriography and the findings appeared normal in ten extremities; nine of these extremities had normal pulses and one had a diminished but palpable pulse. A minimal injury (intimal defect, 3; narrowing, 4) was demonstrated in seven extremities, five with normal pulses and two with diminished pulses.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone grafting is frequently used to assist in reconstruction of bone defects following limb salvage procedures in tumor surgery. These defects can be large and require the use of bulk allograft and/or significant amounts of particulate graft material. This article reports a clinic's preliminary results with a bone graft containment material that serves as an artificia! periosteum. This radiographic review evaluates the material's ability to prevent migration of bone graft and ascertain progressive callus formation. Early results have been encouraging.

Neural fibrolipoma is a benign mass of fibrofatty tissue intermixed with nerve tissue. It most commonly occurs in the upper extremity in infants and children, usually affecting the median nerve. This report describes surgical resection of a rare neural fibrolipoma of the foot in a 32-year-old woman.