Introductory address for the American Pediatric Society's 2015 John Howland Award Recipient, Catherine D. DeAngelis.

Presented by Julia A. McMillan, MD, Professor of Pediatrics, Executive Vice Chair, Department of Pediatrics, and Associate Dean for Graduate Medical Education, Johns Hopkins University School of Medicine, at the 2015 Annual Meeting of the Pediatric Academic Societies, San Diego, CA.

Retrieval analysis of three generations of Biolox® femoral heads: spectroscopic and SEM characterisation.

Wear and osteolysis continue to be the major reasons for revision surgery in Total Hip Arthroplasty. The introduction of the ceramic-on-ceramic bearings eliminates the problem of polyethylene wear debris. During the last 40 years, three generations of Biolox® ceramics were developed (Biolox®, Biolox® forte, and Biolox® delta), each better than the previous from the density, grain size and purity point of view. We conducted a retrieval study on 15 Biolox® femoral heads (Biolox®, Biolox® forte, and Biolox® delta) articulating against liners of the same type. Surface properties and residual stress were assessed using SEM, fluorescence and Raman spectroscopy. At SEM examination, the Biolox® delta retrievals showed a lower wear than the previous generations. The fluorescence measurements suggested different wear mechanisms in the three sets of retrievals. Micro-cracking was predominant in Biolox®, while in Biolox® forte and Biolox® delta a wider range of residual stress values was observed upon wear. Surface polishing was observed only in Biolox® and Biolox® forte. Raman spectroscopy of Biolox® delta femoral heads showed a progressive improvement in material composition. Wear induced a tetragonal to monoclinic transformation. The Raman results on the retrievals, here reported for the first time, allowed to validate the in vitro ageing protocols proposed in the literature to simulate the effects of the in vivo wear.

Mobile or fixed unicompartmental knee prostheses? In-vitro wear assessments to solve this dilemma.

The unicompartmental knee prosthesis is an attractive alternative to total knee arthroplasty. Current UKP devices can be subdivided into two groups based on different design principles: fixed bearing knees, where the ultra-high molecular weight polyethylene meniscal component snap or press fits into the tibial tray, and mobile bearing designs which facilitate movement of the insert relative to the tray. The present study was aimed at comparing the in-vitro wear behaviour of fixed and mobile unicompartmental knee menisci under two configurations: the femoral components were cemented into a custom-made metallic block or, as a novelty of the present study, into a synthetic femur (i.e. under conditions which should better reproduce the in-vivo behaviour). Analyses were performed using a displacement-control knee wear simulator with "three-plus-one" stations. All the kinematics tests were set in accordance with the ISO 14243-1,2,3. Fixed and mobile polyethylene menisci showed a different wear behaviour: the fixation-frame influenced directional load transfer through each component in a qualitative and quantitative way. In fact, gravimetric results showed that under the metal block holder fixation, mobile components worn more than fixed components (weight losses of 8.7±2.0 mg and 2.6±1.09 mg, respectively); on the other hand, under the synthetic femur configuration, differences in wear behaviour were less pronounced and mobile menisci underwent a slightly lower weight loss than fixed components (4.5±2.2 mg vs. 6.7±1.4 mg). This different trend was explained in relation to the kinematic schemes of the two fixation methods. Raman spectroscopy, used to evaluate the UHMWPE crystallinity changes induced by mechanical stress, showed that mobile menisci specimens were more affected than the fixed components in both their superior and inferior surfaces, independent of the fixation-frame. In conclusion, if tested under conditions which should better reproduce the in-vivo behaviour, mobile UKPs did not show a worse wear behaviour than fixed components in terms of weight losses, although UHMWPE changes at the molecular scale could be detrimental.

Fluoride-containing nanoporous calcium-silicate MTA cements for endodontics and oral surgery: early fluorapatite formation in a phosphate-containing solution.

AIM: To test the chemical-physical properties and apatite-forming ability of experimental fluoride-doped calcium silicate cements designed to create novel bioactive materials for use in endodontics and oral surgery. METHODOLOGY: A thermally treated calcium silicate cement (wTC) containing CaCl(2) 5%wt was modified by adding NaF 1%wt (FTC) or 10%wt (F10TC). Cements were analysed by environmental scanning electron microscopy with energy-dispersive X-ray analysis, IR and micro-Raman spectroscopy in wet conditions immediately after preparation or after ageing in a phosphate-containing solution (Dulbecco's phosphate-buffered saline). Calcium and fluoride release and pH of the storage solution were measured. The results obtained were analysed statistically (Tukey's HSD test and two-way anova). RESULTS: The formation of calcium phosphate precipitates (spherulites) was observed on the surface of 24 h-aged cements and the formation of a thick bone-like B-type carbonated apatite layer (biocoating) on 28 day-aged cements. The rate of apatite formation was FTC>F10TC>wTC. Fluorapatite was detected on FTC and F10TC after 1 day of ageing, with a higher fluoride content on F10TC. All the cements released calcium ions. At 5 and 24 h, the wTC had the significantly highest calcium release (P<0.001) that decreased significantly over the storage time. At 3-28 days, FTC and F10TC had significantly higher calcium release than wTC (P<0.05). The F10TC had the significantly highest fluoride release at all times (P<0.01) that decreased significantly over storage time. No significant differences were observed between FTC and wTC. All the cements had a strong alkalinizing activity (OH(-) release) that remained after 28 days of storage. CONCLUSIONS: The addition of sodium fluoride accelerated apatite formation on calcium silicate cements. Fluoride-doped calcium silicate cements had higher bioactivity and earlier formation of fluorapatite. Sodium fluoride may be introduced in the formulation of mineral trioxide aggregate cements to enhance their biological behaviour. F-doped calcium silicate cements are promising bone cements for clinical endodontic use.

Title VII and the development and promotion of national initiatives in training primary care clinicians in the United States.

The Title VII, Section 747 (Title VII) legislation, which authorizes the Training in Primary Care Medicine and Dentistry grant program, provides statutory authority to the Health Resources and Services Administration (HRSA) to award contracts and cooperative agreements aimed at enhancing the quality of primary care training in the United States.More than 35 contracts and cooperative agreements have been issued by HRSA with Title VII federal funds, most often to national organizations promoting the training of physician assistants and medical students and representing the primary care disciplines of family medicine, general internal medicine, and general pediatrics. These activities have influenced generalist medicine through three mechanisms: (1) building collaboration among the primary care disciplines and between primary care and specialty medicine, (2) strengthening primary care generally through national initiatives designed to develop and implement new models of primary care training, and (3) enhancing the quality of primary care training in specific disease areas determined to be of national importance.The most significant outcomes of the Title VII contracts awarded to national primary care organizations are increased collaboration and enhanced innovation in ambulatory training for students, residents, and faculty. Overall, generalist competencies and education in new content areas have been the distinguishing features of these initiatives. This effort has enhanced not only generalist training but also the general medical education of all students, including future specialists, because so much of the generalist competency agenda is germane to the general medical education mission.This article is part of a theme issue of Academic Medicine on the Title VII health professions training programs.

Computer-based documentation: effects on parent-provider communication during pediatric health maintenance encounters.

OBJECTIVE: The goal was to investigate the impact of a computer-based documentation tool on parent-health care provider communication during a pediatric health maintenance encounter. METHODS: We used a quasiexperimental study design to compare communication dynamics between clinicians and parents/children in health maintenance visits before and after implementation of the ClicTate system. Before ClicTate use, paper forms were used to create visit notes. The children examined were

Evaluation activities to strengthen an injury prevention resource center for urban families.

The Johns Hopkins Children's Safety Center (CSC) is a unique health care provider and patient education resource that elevates the attention injury prevention receives in a medical setting and reduces barriers to injury prevention experienced by low-income, urban families, the Center's priority population. This article describes the CSC's development, implementation, and selected elements of its evaluation. Because evaluation has played an important role in the CSC from its inception through its implementation and sustainability, three evaluation activities are described: process evaluation to monitor activity, impact evaluation to understand its effects on parents' safety behaviors, and qualitative interviews with CSC visitors and non-visitors to enhance services. Implications of each evaluation activity are described and recommendations are made for strengthening the CSC.

Effects of improved access to safety counseling, products, and home visits on parents' safety practices: results of a randomized trial.

OBJECTIVE: To present the results of an intervention trial to enhance parents' home-safety practices through pediatric safety counseling, home visits, and an on-site children's safety center where parents receive personalized education and can purchase reduced-cost products. DESIGN: Pediatricians were randomized to a standard- or an enhanced-intervention group. Parents of their patients were enrolled when the patient was 6 months or younger and observed until 12 to 18 months of age. SETTING: A hospital-based pediatric resident continuity clinic that serves families living in low-income, inner-city neighborhoods. PARTICIPANTS: First- and second-year pediatric residents and their patient-parent dyads. INTERVENTIONS: Parents in the standard-intervention group received safety counseling and referral to the children's safety center from their pediatrician. Parents in the enhanced-intervention group received the standard services plus a home-safety visit by a community health worker. OUTCOMES: Home observers assessed the following safety practices: reduction of hot-water temperature, poison storage, and presence of smoke alarms, safety gates for stairs, and ipecac syrup. RESULTS: The prevalence of safety practices ranged from 11% of parents who stored poisons safely to 82% who had a working smoke alarm. No significant differences in safety practices were found between study groups. However, families who visited the children's safety center compared with those who did not had a significantly greater number of safety practices (34% vs 17% had > or 3). CONCLUSIONS: Home visiting was not effective in improving parents' safety practices. Counseling coupled with convenient access to reduced-cost products appears to be an effective strategy for promoting children's home safety.