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P-15 is a 15-amino-acid-long biomimetic peptide widely demonstrated to enhance osteogenesis in vivo. Despite the prevalence of polyether-ether-ketone (PEEK) in interbody device manufacturing, a growing body of evidence suggests it may produce an unfavorable immune response. The purpose of this preliminary study was to characterize the immune response and new bone growth surrounding PEEK implants with and without a P-15 peptide-based osteobiologic. A bilateral femoral defect model was conducted using New Zealand white rabbits. A total of 17 test subjects received one implant in each distal femur, either with or without bone graft material. Animals were allowed to survive to 4 or 8 weeks, at which time the femurs were collected and subjected to micro-computer tomography (microCT) or cytokine analysis. MicroCT analysis included the quantification of bone growth and density surrounding each implant. The cytokine analysis of periprosthetic tissue homogenates included the quantification of interleukins (ILs) and TNF-α expression via ELISA kits. Improvements in bone volume were observed in the P-15 cohort for the regions of interest, 500–136 and 136–0 µm from the implant surface, at 8 weeks post-op. Concentrations of IL-1β, IL-4, and IL-6 cytokines were significantly higher in the P-15 cohort compared to the PEEK cohort at the 4-week timepoint. Significant reductions in the concentrations of IL-4 and IL-6 cytokines from the 4- to 8-week cohort were observed in the P-15 cohort only. The P-15 peptide has the potential to modulate the immune response to implanted materials. We observed improvements in bone growth and a more active micro-environment in the P-15 cohort relative to the PEEK control. This may indicate an earlier transition from the inflammatory to remodeling phase of healing.

Bone regeneration is a complex multicellular process involving the recruitment and attachment of osteoprogenitors and their subsequent differentiation into osteoblasts that deposit extracellular matrixes. There is a growing demand for synthetic bone graft materials that can be used to augment these processes to enhance the healing of bone defects resulting from trauma, disease or surgery. P-15 is a small synthetic peptide that is identical in sequence to the cell-binding domain of type I collagen and has been extensively demonstrated in vitro and in vivo to enhance the adhesion, differentiation and proliferation of stem cells involved in bone formation. These events can be categorized into three phases: attachment, activation and amplification. This narrative review summarizes the large body of preclinical research on P-15 in terms of these phases to describe the mechanism of action by which P-15 improves bone formation. Knowledge of this mechanism of action will help to inform the use of P-15 in clinical practice as well as the development of methods of delivering P-15 that optimize clinical outcomes.

• Deliberate practice activities can improve learner competence and performance. • Deliberate practice was integrated into CPR learner activities as a QI initiative. • Repetition of deliberate practice actions can apply to any health care discipline. Deliberate practice offers a foundation for learning experiences based on real-life situations through repetition. Single demonstrations of a skill are often ineffective in determining mastery in undergraduate nursing students. Ninety-eight fourth-semester learners enrolled in the critical care course of a pre-baccalaureate program. A deliberate practice approach to learning was implemented in a fourth-semester undergraduate nursing course to evaluate learner knowledge, skills, and performance, as a quality improvement initiative. Multiple activities comprised of skills stations, lecture, an ECG review, and a simulation-based experience were used to allow learners to gain mastery. Evidence revealed that a combined SBE in classroom and simulation lab help learners retain knowledge. Learners reported this approach also improved their ability to critically think and confidence in performance. The implementation of deliberate practice in the simulation environment allows for exposure to real life circumstances in a controlled atmosphere, helping learners preserve information and understanding. [ABSTRACT FROM AUTHOR]

Background: Data are scarce on the efficacy of a second radiosurgery (SRS) treatment of vestibular schwannoma that has progressed following initial treatment with SRS. We sought to report the outcome of our repeat SRS series with long-term imaging follow-up. Materials and methods: We retrospectively analyzed 6 patients who met the following criteria: Repeat SRS at our institution between 1995 and 2018; solitary unilateral tumor; no evidence of neurofibromatosis; and magnetic resonance (MR) planning for both SRS treatments. All treatments were delivered with a linear accelerator-based system using head frame immobilization. The prescribed dose to the periphery of the tumor was 12.5 Gy in all initial and repeat SRS treatments, except for one repeat treatment to 10 Gy. Results: Follow-up with MR scan following the second SRS treatment was a median 8.4 years. The tumor control rate (lack of progression) following the second SRS treatment was 83% (5/6). Actuarial 10-year outcomes following repeat SRS were: tumor control, 80%; absolute survival, 80%; and cause-specific survival, 100%. Of the patients with at least minimal hearing retention before initial SRS, none had ipsilateral hearing preservation after initial radiation treatment. Improvement in any pretreatment cranial nerve deficits was not seen. The only permanent grade ≥ 3 toxicity from repeat SRS was a case of infraorbital nerve deficit. No patient developed a stroke, malignant transformation, induced second tumor, or facial nerve deficit. Conclusion: There was excellent overall survival, tumor control, and low morbidity in our series for recurrent vestibular schwannoma submitted to repeat single-fraction SRS, supporting additional studies of this treatment strategy. [ABSTRACT FROM AUTHOR]

Respected authors recommend broadening the radiation oncology (RO) scope-of-practice by taking more responsibility for the general medical care of our patients, directing the delivery of systemic cancer treatments that avoid the high toxicity of cytotoxic chemotherapy, managing palliative care, and supervising inpatient services for brachytherapy cases and problems related to radiation toxicity. The purpose of these changes is to increase RO involvement in clinical decision making and to avoiding becoming pigeon-holed as technicians instead of oncologists. There are no data estimating the financial implications of substituting traditional radiation oncology practice with that of an expanded clinical role. We sought to fill this void with a general proof-of-principle analysis based on current benchmark data. To determine the relative value units (RVU) of a blended radiation oncology practice, we selected the specialties of general internal medicine, hospital medicine, and palliative care as these fields most closely match the scope of the broadened clinical roles, which supporters of a more diversified radiation oncology practice typically advocate. To estimate the financial implications of a blended radiation oncology practice, we retrieved salary data by specialty and academic rank from the Clinical Practice Solutions Center report of annual RVU generation and the American Association of Medical Colleges annual faculty salary survey. For an assistant professor, this simulation estimates an 11% to 15% decrease in RVU generation for the median assistant professor operating with a 20% blended practice which, in turn, translates to a 7% to 9% decrease in total salary. The calculations for full professor demonstrate a similar decrease in total salary of approximately 8% to 9%. [ABSTRACT FROM AUTHOR]

Confusion exists around the terms 'Oral Surgeon' and 'Oral and Maxillofacial Surgeon'. Historical terms and international differences have added to this confusion. Recently, the University of Sydney has begun to offer a Doctor of Clinical Dentistry in Oral Surgery to graduate dentists. With this new dental specialty entering the Australian workforce, distinction must be made between their role and the role of Oral and Maxillofacial Surgeons to facilitate effective referral pathways. A cross sectional survey of 3rd and 4th year dental students was distributed in June 2019. Students were queried with regards to their perception of the scope of practice of Oral Surgeons and Oral and Maxillofacial Surgeons as well as their knowledge of the training pathways and level of interest in pursuing either pathway. A total of 85% of students responded. Responses indicated a general awareness of the increased scope of practice of Oral and Maxillofacial Surgeons with some exceptions. No significant difference was seen between third and fourth year responses. Knowledge of both training pathways was lacking. Further education is required with regards to the scope of practice of both specialties. A lack of exposure to Oral and Maxillofacial Surgery during the undergraduate years may be partly to blame. Consideration should be given to the renaming of Oral Surgery to Surgical Dentistry. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the accuracy of three dimensionally (3D) printed models of the bony orbit derived from magnetic resonance imaging (MRI) for the purpose of preoperative plate bending in the setting of orbital blowout fracture. Retrospective computed tomography (CT) and MRI data from patients with suspected orbital fractures were used. Virtual models were manually generated and analysed for spatial accuracy of the fracture margins. 3D-printed models were produced and orbital fan plates bent by a single operator. The plates were then digitized and analysed for spatial discrepancy using reverse engineering software. Seven orbital blowout fractures were evident in six orbits. Analysis of the virtual models revealed high congruence between blowout fracture margins on CT and MRI (n = 7, average deviation 0.85 mm). Three zygomaticomaxillary complex fractures were seen, for which MRI did not demonstrate the same accuracy. For plates bent to the 3D-printed models of blowout fractures (n = 6), no significant difference was found between those bent to CT versus those bent to MRI when compared for average surface and average border deviation (Wilcoxon signed rank test). Orbital blowout fractures can be defined on MRI with clinically acceptable accuracy. 3D printing of orbital biomodels from MRI for bending reconstructive plates is an acceptable and accurate technique. [ABSTRACT FROM AUTHOR]

• Few case reports describe intracranial arachnoid cysts in pregnant women. • Parturients with arachnoid cysts may be suitable for neuraxial anaesthesia. • Anaesthesia options for these pregnant women are discussed. Choosing the type of intrapartum anaesthesia for pregnant women with intracranial arachnoid cysts can be challenging due to a lack of research. We report the intrapartum anaesthetic management of a 25-year-old woman with a known 10 cm arachnoid cyst. By means of a literature review and discussion of safety surrounding neuraxial techniques, this report will help to inform obstetric anaesthesia practice. Overall, in the absence of raised intracranial pressure, neuraxial analgesia and anaesthesia during the intrapartum period appears to be a safe option. [ABSTRACT FROM AUTHOR]