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The Society of Nuclear Medicine and Molecular Imaging convened a task group to examine the evidence for the risk of carcinogenesis from low-dose radiation exposure and to assess evidence in the scientific literature related to the overall validity of the linear no-threshold (LNT) hypothesis and its applicability for use in risk assessment and radiation protection. In the low-dose and dose-rate region, the group concluded that the LNT hypothesis is invalid as it is not supported by the available scientific evidence and, instead, is actually refuted by published epidemiology and radiation biology. The task group concluded that the evidence does not support the use of LNT either for risk assessment or radiation protection in the low-dose and dose-rate region.

In the absence of systematic cardiovascular preparticipation screening (PPS) practices in Canada, the Canadian Cardiovascular Society and Canadian Heart Rhythm Society published a joint position statement outlining PPS recommendations for competitive athletes in an effort to standardize screening. The Queen’s University Cardiovascular Screening and Care of Athletes Program aimed to translate these recommendations into practice. Screening packages were administered to athletes in 2017 and 2018. Each package required completion of a medical/history questionnaire, a physician’s examination, and 12-lead electrocardiogram performed by the athlete’s primary care physician. A tiered approach to screening, as recommended by the position statement, was implemented. A multidisciplinary team flagged at-risk athletes and determined the need for follow-up testing and participation eligibility. Over a 2-year period, 517 varsity athletes were screened, with 438 (84.7%) completing all recommended screening components. Analysis of completed packages resulted in 114 (26.0%) athletes flagged for initial review. After subsequent review by an emergency care physician, only 12 (2.7%) athletes required further referral to cardiology for assessment or further testing. All athletes referred for cardiology assessment were cleared for participation, except for one, who was eventually cleared after a shared decision-making process and cardiovascular intervention. The Queen’s University Cardiovascular Screening and Care of Athletes Program shows the successful implementation of a cardiovascular PPS program that used shared decision-making and a multidisciplinary approach to screening, allowing for efficiency and effective resource utilization.

Internationally, evidence-based practice (EBP) is recognised as a foundational element of healthcare professional education. Achieving competency in this area is a complex undertaking that is reflected in disparities between ‘best EBP’ and actual clinical care. The effective development and implementation of professional education to facilitate EBP remains a major and immediate challenge. To ascertain nuanced perspectives on the provision of EBP education internationally, interviews were conducted with five EBP education experts from the UK, Canada, Australia and New Zealand. Definitive advice was provided in relation to (1) EBP curriculum considerations, (2) teaching EBP and (3) stakeholder engagement in EBP education. While a considerable amount of EBP activity throughout health profession education is apparent, effectively embedding EBP throughout curricula requires further development, with a ‘real-world’ pragmatic approach that engenders dialogue and engagement with all stakeholders required.

Autophagy, an autophagosome and lysosome-based eukaryotic cellular degradation system, has previously been implicated in lifespan regulation in different animal models. In this report, we show that expression of the RNAi transgenes targeting the transcripts of the key autophagy genes Atg1or Atg18in adult fly muscle or glia does not affect the overall levels of autophagosomes in those tissues and does not change the lifespan of the tested flies but the lifespan reduction phenotype has become apparent when Atg1 RNAior Atg18 RNAiis expressed ubiquitously in adult flies or after autophagy is eradicated through the knockdown of Atg1 or Atg18 in adult fly adipocytes. Lifespan reduction was also observed when Atg1 or Atg18 was knocked down in adult fly enteroblasts and midgut stem cells. Overexpression of wild-type Atg1 in adult fly muscle or adipocytes reduces the lifespan and causes accumulation of high levels of ubiquitinated protein aggregates in muscles. Our research data have highlighted the important functions of the key autophagy genes in adult fly adipocytes, enteroblasts, and midgut stem cells and their undetermined roles in adult fly muscle and glia for lifespan regulation.

Aims:To report the clinical and pathological features of a benign fibrous histiocytoma of the xanthomatous subtype in the perilimbal conjunctiva and adjacent sclera in a youth. Methods:An 11-year-old Caucasian boy presented with a yellowish dome-shaped conjunctival mass abutting the inferotemporal limbus of the left eye. The tumor measured 4 mm in its maximum diameter. The lesion was excised and was noted to extend into the sclera. Three years postoperatively, there was no evidence of recurrence. Results:Histopathological examination disclosed a highly cellular lesion composed predominantly of benign-appearing foamy histiocytes without multinucleated giant cells. The tumor contained sparse fibrous septa without a storiform configuration. Immunohistochemical analysis showed diffuse cytoplasmic positive staining with adipophilin, CD34, and CD163. Conclusion:A lesion comprised of numerous homogeneous foamy histiocytes without multinucleated giant cells in the perilimbal conjunctiva and adjacent sclera of a youth is presented as a unique case of a rare variant of fibrous histiocytoma of the xanthomatous subtype.

Groundwater flow regimes in the seasonally thawed soils in areas of continuous permafrost are relatively unknown despite their potential role in delivering water, carbon, and nutrients to streams. Using numerical groundwater flow models informed by observations from a headwater catchment in arctic Alaska, United States, we identify several mechanisms that result in substantial surface‐subsurface water exchanges across the land surface during downslope transport and create a primary control on dissolved organic carbon loading to streams and rivers. The models indicate that surface water flowing downslope has a substantial groundwater component due to rapid surface‐subsurface exchanges across a range of hydrologic states, from unsaturated to flooded. Field‐based measurements corroborate the high groundwater contributions, and river dissolved organic carbon concentrations are similar to that of groundwater across large discharge ranges. The persistence of these groundwater contributions in arctic watersheds will influence carbon export to rivers as thaw depth increases in a warmer climate. This paper shows that groundwater processes have a dominant role in controlling carbon export from the land to streams in permafrost terrain. We use hydrologic models to show that microtopography on the land surface drives the rapid exchange of overland flow with shallow groundwater. In other words, the water (porpoises) from just above to just below the land surface and back again as it moves downslope. Combined with the rapid leaching of organic carbon from soils, these findings provide a mechanistic explanation for two decades of measurements showing high concentrations of carbon in soils and streams during high flow conditions for both spring snowmelt and summer storms. During drier time periods, groundwater contributions from the thin thawed layer make up the flow in streams and keep dissolved organic carbon concentrations high. The persistence of these groundwater contributions in arctic watersheds will influence carbon export to rivers as thaw depth increases in a warmer climate. Surface‐subsurface water exchanges across the landscape control solute export from watershedsOverland flow water contains substantial amounts of groundwaterConstant stream DOC over large flow ranges and varied active layer thaw corroborate the role of surface‐subsurface exchanges in DOC export

As noted in part 1 of this series, periprocedural cardiac arrest (PPCA) can differ greatly in etiology and treatment from what is described by the American Heart Association advanced cardiac life support algorithms, which were largely developed for use in out-of-hospital cardiac arrest and in-hospital cardiac arrest outside of the perioperative space. Specifically, there are several life-threatening causes of PPCA of which the management should be within the skill set of all anesthesiologists. However, previous research has demonstrated that continued review and training in the management of these scenarios is greatly needed and is also associated with improved delivery of care and outcomes during PPCA. There is a growing body of literature describing the incidence, causes, treatment, and outcomes of common causes of PPCA (eg, malignant hyperthermia, massive trauma, and local anesthetic systemic toxicity) and the need for a better awareness of these topics within the anesthesiology community at large. As noted in part 1 of this series, these events are always witnessed by a member of the perioperative team, frequently anticipated, and involve rescuer–providers with knowledge of the patient and the procedure they are undergoing or have had. Formulation of an appropriate differential diagnosis and rapid application of targeted interventions are critical for good patient outcome. Resuscitation algorithms that include the evaluation and management of common causes leading to cardiac in the perioperative setting are presented. Practicing anesthesiologists need a working knowledge of these algorithms to maximize good outcomes.

Cardiac arrest in the operating room and procedural areas has a different spectrum of causes (ie, hypovolemia, gas embolism, and hyperkalemia), and rapid and appropriate evaluation and management of these causes require modification of traditional cardiac arrest algorithms. There is a small but growing body of literature describing the incidence, causes, treatments, and outcomes of circulatory crisis and perioperative cardiac arrest. These events are almost always witnessed, frequently known, and involve rescuer providers with knowledge of the patient and their procedure. In this setting, there can be formulation of a differential diagnosis and a directed intervention that treats the likely underlying cause(s) of the crisis while concurrently managing the crisis itself. Management of cardiac arrest of the perioperative patient is predicated on expert opinion, physiologic rationale, and an understanding of the context in which these events occur. Resuscitation algorithms should consider the evaluation and management of these causes of crisis in the perioperative setting.

It has been previously demonstrated that IC50values for inhibition of digoxin transport across confluent polarized cell monolayers are system-dependent. Digoxin IC50data from five laboratories participating in the P-glycoprotein (P-gp) IC50Initiative, using Caco-2, MDCKII-hMDR1 or LLC-PK1-hMDR1 cells, were fitted by the structural mass action kinetic model for P-gp–mediated transport across confluent cell monolayers. We determined their efflux-active P-gp concentration [T(0)], inhibitor elementary dissociation rate constant from P-gp (krQ), digoxin basolateral uptake clearance (kB), and inhibitor binding affinity to the digoxin basolateral uptake transporter (KQB). We also fitted the IC50data for inhibition of digoxin transport through monolayers of primary human proximal tubule cells (HPTCs). All cell systems kinetically required a basolateral uptake transporter for digoxin, which also bound to all inhibitors. The inhibitor krQwas cell system–independent, thereby allowing calculation of a system-independent Ki. The variability in efflux-active P-gp concentrations and basolateral uptake clearances in the five laboratories was about an order of magnitude. These laboratory-to-laboratory variabilities can explain more than 60% of the IC50variability found in the principal component analysis plot in a previous study, supporting the hypothesis that the observed IC50variability is primarily due to differences in expression levels of efflux-active P-gp and the basolateral digoxin uptake transporter. HPTCs had 10- to 100-fold lower efflux-active P-gp concentrations than the overexpressing cell lines, whereas their digoxin basolateral uptake clearances were similar. HPTC basolateral uptake of digoxin was inhibited 50% by 10 μM ouabain, suggesting involvement of OATP4C1.

Treatment of high-risk neuroblastoma now includes antibody based antitumor immunotherapy as part of standard care. Although this therapy has resulted in dramatic improvements in survival, it is associated with significant side effects. Children with underlying respiratory issues, and in particular asthma, may be more susceptible to immunotherapy associated respiratory compromise and pulmonary complications. Early routine involvement of pulmonology care is warranted for these patients in an effort to allow maximal delivery of immunotherapy and minimize acute and long-term complications.

Design and objectives To identify and compare how intensive care unit specialists in the United Kingdom and Australia and New Zealand self-reportedly define, assess and manage fluid overload in critically ill patients using a structured online questionnaire.Results We assessed 219 responses. Australia and New Zealand and United Kingdom intensive care unit specialists reported using clinical examination findings, bedside tools and radiological features to assess fluid status, diagnose fluid overload and initiate fluid removal in the critically ill. An elevated central venous pressure is not regarded as helpful in diagnosing fluid overload and targeting a clinician-set fluid balance is the most popular management strategy. Renal replacement therapy is used ahead of more diuretic therapy in patients who are oligo/anuric, or when diuretic therapy has not generated an adequate response.Conclusions This self-reported account of practice by United Kingdom and Australia and New Zealand intensivists demonstrates that fluid overload remains poorly defined with variability in both management and practice.

Purpose: This Commentary is a review and critique of arguments that oppose the desirability and impact of professional collaboration in education. The purpose of this paper is to analyze two recent high-profile reviews of professional development and collaboration. The analysis is informed by a historical typology of five phases of professional collaboration in theory and practice. Design/methodology/approach: The Commentary reviews and summarizes selected key texts that represent different phases in the development of advocacy for and research concerning the emergence of professional collaboration. It then critiques the methodology, findings, and recommendations of two key critiques of professional collaboration and development that have been widely disseminated for educators and policymakers. Findings: Contrary to the views of its opponents, professional collaboration as a whole has a record of indirect, long term, yet clear and positive effects on teachers and students. Particular kinds of professional collaboration can vary a great deal in quality and impact, however. Short-term collaborative interventions, such as data teams, are often dependent for their success on the prior existence of deeper cultures and processes. These processes and cultures characterize high-performing systems globally. Advocacy for competitive alternatives is based on insufficient evidence. Originality/value: Although advocacy for more competition in public school systems is common, high-profile critiques of professional collaboration are relatively new. This paper engages with these critiques from a broader historical perspective, and finds they have serious flaws of reasoning and methodology. Thus far, the critiques provide insufficient warrant for moves toward more competitive systems of schooling and teaching.

Hepatic function and pulmonary function are interrelated with failure of one organ system affecting the other. With improved therapies, patients with concomitant hepatic and pulmonary failure increasingly enjoy a good quality of life and life expectancy. Therefore, the prevalence of such patients is increasing with more presenting for both emergent and elective surgical procedures. Hypoxemia requires a thorough evaluation in patients with end-stage liver disease. The most common etiologies respond to appropriate therapy. Portopulmonary hypertension and hepatopulmonary syndrome are associated with increased perioperative morbidity and mortality. It is incumbent on the anesthesiologist to understand the physiology of liver failure and its early effect on pulmonary function to ensure a successful outcome.

Somewhere along the line airline maintenance technicians feel the pressure of 'not delaying a flight.' This in a way is a double-edged sword. On one hand, gaining revenue for the [...]