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In the setting of periprosthetic total hip and knee arthroplasty (THA/TKA) infection, plating of the femur may be necessary for fracture fixation, prophylactic fixation of the femur, poor bone quality, or infected femoral shaft nonunion. The purpose of this study was to investigate infection control rates and fracture healing in patients receiving antibiotic cement coated plates in the setting of infected nonunion and periprosthetic infections.We retrospectively reviewed a series of ten patients who had an antibiotic coated plate placed in the setting of periprosthetic infection or infected nonunion with a minimum follow-up of six months. 80 g of Simplex bone cement (Stryker, Mahwah, NJ) were mixed with 4 g of powdered vancomycin and 4.8 g of powdered tobramycin and applied to a dynamic compression plate with locking screw guides in every hole. The antibiotic loaded cement was allowed to harden before implantation. Outcome measures were designed to assess for fracture healing defined as three out of four cortices united on radiographs along with bearing full weight without pain and evidence of infection control defined as normalized erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in the absence of antibiotic treatment with no clinical signs of infection.Ten patients were treated with an antibiotic cement coated plate in the settings of infectious nonunion and periprosthetic infection and followed for an average of three years (mean 21.4 months, seven months to 61 months). Eight patients (80%) went on to successful control of infection after initial procedure. Two patients developed chronic drainage and had a second antibiotic spacer with antibiotic cement coated plate placed before the infection was controlled. All patients obtained successful control of infection at latest follow-up showing no clinical signs of infection, normalized laboratory markers, and negative culture results. There were no reported mechanical failures of the implant, fractures of the femur, or soft tissue complications.An antibiotic cement coated plating technique is a viable option for periprosthetic THA and TKA infections requiring plating of the femur or in patients with an infected nonunion.

To meet the Paris Agreement targets, in addition to rapid emission reductions, carbon dioxide needs to be removed from the atmosphere with Negative Emission Technologies (NETs). On one hand, these solutions seem promising; on the other hand, they have significant and poorly estimated uncertainties and risks related to their potential to remove atmospheric carbon and wider impacts on the Earth system. One previously largely unexplored aspect of NETs is whether the uncertainty in NETs and e.g. transient climate response to cumulative CO2 emissions (TCRE) are coupled to any degree, e.g. could some NETs have lower carbon removal potential if TCRE is high. We estimate how TCRE and selected NETs’ carbon removal potential are dependent on climate system parameters using Perturbed Parameter Ensemble (PPE) with the University of Victoria Earth System Climate Model (UVic ESCM) and Gaussian Process (GP) emulator. Our aim is to explore and quantify any potential correlation between the carbon removal potential of single NETs and TCRE. The NETs considered are afforestation, reforestation, ocean alkalinization, ocean iron fertilization and direct air capture, which all except the last one depend on the perturbed parameters. The parameters of interest are chosen according to their expected impact on the climate and carbon uptake, constrained according to observations, and perturbed based on their prior probability distribution functions (PDFs). Then, to explore the parameter’s space, we use GP emulators to estimate model outputs as surrogate of actual ESM runs, which would be computationally too expensive. The emulators are created for the preindustrial spin-up, historical period, future control scenario and one for each NET scenario. They are trained through 300 simulations, considering 20 perturbed parameters. This analysis yields the correlation between the carbon removal potential of each NET and TCRE, and the contribution of each perturbed parameter to these two metrics. The preliminary results from the 300-member ensemble give a mean TCRE of 1.63 °C/1000 PgC, which is consistent with the best estimate of 1.65 °C/1000 PgC reported by the IPCC AR6 WGI (2021). The simulations with a high TCRE also tended to have a high ocean iron fertilization’s potential, meaning that some NETs are potentially more effective in removing atmospheric carbon dioxide if the temperature change per cumulative carbon dioxide emissions is high. Identifying such correlations between TCRE and NETs’ potential allows designing more robust mitigation strategies including portfolios of NETs that hedge against high TCRE.

This report provides an overview on the cooperation activities with relevant EU projects and other initiatives on negative emission technologies in the second reporting period of the OceanNETs project (01.01.2022 – 31.12.2022).

The notion that the physician has a responsibility to both the patient in their care and the community in which they reside has been a source of inspiration and tension within the profession for centuries. The profession of Pediatrics has uniquely incorporated advocacy into its training programs and will likely continue to incorporate advocacy into its professional standards for the foreseeable future. In this article, we review the history of advocacy within the profession, outline the skills needs for successful child health advocacy and offer examples of how advocacy combined with pediatric practice has improved the lives of children.

The consideration of marine biogeochemistry is essential for simulating the carbon cycle in an Earth system model. Here we present the implementation and evaluation of a marine biogeochemical model, Model of Oceanic Pelagic Stoichiometry (MOPS) in the Flexible Ocean and Climate Infrastructure (FOCI) climate model. FOCI-MOPS enables the simulation of marine biological processes, the marine carbon, nitrogen and oxygen cycles, air-sea gas exchange of CO2 and O2, and simulations with prescribed atmospheric CO2 or CO2 emissions. A series of experiments covering the historical period (1850–2014) were performed following the DECK (Diagnostic, Evaluation and Characterization of Klima) and CMIP6 (Coupled Model Intercomparison Project 6) protocols. Overall, modelled biogeochemical tracer distributions and fluxes, as well as transient evolution in surface air temperature, air-sea CO2 fluxes, and changes of ocean carbon and heat, are in good agreement with observations. Modelled inorganic and organic tracer distributions are quantitatively evaluated by statistically-derived metrics. Results of the FOCI-MOPS model, also including sea surface temperature, surface pH, oxygen (100–600 m), nitrate (0–100 m), and primary production, are within the range of other CMIP6 model results. Overall, the evaluation of FOCI-MOPS indicates its suitability for Earth climate system simulations.

Ever since their origin more than one half-century ago, microneurographic recordings of sympathetic nerve activity have significantly advanced our understanding of the generation and regulation of central sympathetic outflow in human health and disease. For example, it is now appreciated that a myriad of disease states exhibit chronic sympathetic overactivity, a significant predictor of cardiovascular morbidity and mortality. Although microneurographic recordings allow for the direct quantification of sympathetic outflow, they alone do not provide information with respect to the ensuing sympathetically mediated vasoconstriction and blood pressure (BP) response. Therefore, the study of vascular and/or BP responses to sympathetic outflow (i.e., sympathetic transduction) has now emerged as an area of growing interest within the field of neural cardiovascular control in human health and disease. To date, studies have primarily examined sympathetic transduction under two distinct paradigms: when reflexively evoking sympatho-excitation through the induction of a laboratory stressor (i.e., sympathetic transduction during stress) and/or following spontaneous bursts of sympathetic outflow occurring under resting conditions (i.e., sympathetic transduction at rest). The purpose of this brief review is to highlight how our physiological understanding of sympathetic transduction has been advanced by these studies and to evaluate the primary analytical techniques developed to study sympathetic transduction in humans. We also discuss the framework by which the assessment of sympathetic transduction during stress reflects a fundamentally different process relative to sympathetic transduction at rest and why findings from investigations using these different techniques should be interpreted as such and not necessarily be considered one and the same.

Species dependent on freshwaters are declining globally. Understanding natural and anthropogenic environmental drivers affecting community structure and species occurrence is crucial for planning management and conservation actions. The aim of this study was to determine which landscape characteristics constrain reproductive guilds in wadeable streams and to explore the influence of reproductive strategy on fish occurrence. We expected reproductive guilds to differ in their associations with landscape determinants (i.e., the landscape characteristics found to constrain our reproductive guilds). This study was conducted in the Delaware River Basin in North America. We compiled existing stream survey and geospatial data from multiple government agencies and scientific organizations for 552 sites. We used ordination and regression techniques to identify important landscape determinants and their associations with reproductive guilds. We identified 12 variables that explained 20.6% of the total variation in reproductive guild composition. Slope, land cover and disturbance variables drove the position of reproductive guilds in ordination space. All reproductive guilds differed in the set of landscape-scale determinants that were selected during modelling. Best subsets of variables selected in regression models indicate that reproductive guild occurrence is significantly explained by catchment characteristics. These characteristics include measures of slope, land use and land cover, disturbance, and climate. Differences in determinants and relationships with reproductive guilds found in regression models, and gradients identified, indicate the importance of different landscape-scale determinants for specific reproductive guilds. Furthermore, our findings suggest a link between the environmental requirements of reproductive guilds and landscape-scale characteristics.

Displaced pelvic ring injuries can be challenging to even the experienced orthopedic traumatologist. A temporary external fixation to table construct provides a quick, simple, and accessible means of external skeletal fixation to reliably obtain and maintain stable hemipelvis reduction on the operating room table. The contralateral hemipelvis can be stabilized to the table by use of Steinman pins safely inserted into the subtrochanteric and anterior column regions and later connected to external fixator bars attached to the table. With rigid stabilization, the displaced contralateral pelvic fragment(s) can be reduced in a more vector intentional manner with greater force than the traditional means of pelvic reduction can allow. The skeletal-table fixation technique is presented along with two cases, a combined pelvic-acetabular injury and an isolated pelvic ring injury.

Purpose: Infection following total hip arthroplasty is a challenging and devastating complication. In two-stage revision arthroplasty, antibiotic spacers, although efficacious, can be associated with an unacceptable rate of mechanical complications (e.g., fracture, dislocation). This series describes 15 patients with infected total hip prostheses treated with hybrid cement-screw fixation constrained liner antibiotic spacers to enhance stability and minimize mechanical complications. Materials and Methods: All patients with an infected hip prosthesis undergoing two-stage revision arthroplasty at a single academic medical center were identified and screened for inclusion. Clinical and radiographic data including patient demographics and outcome measures were collected and retrospectively analyzed. Results: Two patients died of unrelated causes at an average of 6-week postoperatively. Infections in the remaining thirteen patients (100%) were successfully eradicated; all underwent uncomplicated revision arthroplasty at a mean duration of 99.5 days after the placement of the antibiotic spacer. No dislocations, fractures, or other mechanical failures of any spacer were observed in this series. Conclusion: The hybrid cement-screw fixation technique for constrained liner antibiotic spacers is a reliable and effective treatment method for eradicating prosthetic joint infections without mechanical complications.

MicroRNA-375 (miR-375) is upregulated in the islets of some diabetics and is correlated with poor outcome. Previous work in our laboratory showed that cyclic adenosine monophosphate (cAMP) reduces miR-375 expression and could provide a way to restore normal miR-375 levels, however the transcription repression mechanism is unknown. Using a chromatin immunoprecipitation assay we show that cAMP response element modulator (CREM) binds to the miR-375 promoter 3-fold above background and we find that CREM represses transcription from the miR-375 promoter 1.8-fold. While investigating miR-375 target genes we discovered that several microRNA:mRNA target prediction algorithms listed human CREM as a target gene of miR-375. The predicted binding site is conserved in primates but not in other species. We found that indeed miR-375 binds to the predicted site on human CREM and represses translation of a green fluorescent protein reporter gene by 30%. These findings suggest a primate-specific double-negative feedback loop, a mechanism that would keep these important β-cell regulators in check.

Transitions from pediatric to adult care by young adults with chronic conditions are fraught with challenges. Poor transitions lead to discontinuities of care that are avoidable with better communication between providers. We tested whether exposure to providers with sustained patient-sharing relationships resulted in fewer emergent admissions of young adults with congenital heart disease (CHD). Care transitions are particularly important for young adults with CHD. Though it is not possible to avoid planned admissions for scheduled procedures, emergency admissions are avoidable with proper care. We tested whether several different patient-sharing relationship measures influenced emergent admissions and found that compared with less severe CHD patients, those with severe CHD experienced a 4 to 10 percentage point decline in emergent admissions given a 5 percentage point increase in practice-level patient-sharing relationships. These results are consistent with our hypothesis that patient sharing improves communication and continuity of care across providers, especially for severe CHD patients.

NEW FINDINGS What is the central question of this study? The prevalence of hypertension in black individuals exceeds that in other racial groups. Despite this well-known heightened risk, the underlying contributory factors remain incompletely understood. We hypothesized that young black men would exhibit augmented beat-to-beat blood pressure variability compared with white men and that black men would exhibit augmented total peripheral resistance variability. What is the main finding and its importance? We demonstrate that young, healthy black men exhibit greater resting beat-to-beat blood pressure variability compared with their white counterparts, which is accompanied by greater variability in total peripheral resistance. These swings in blood pressure over time might contribute to the enhanced cardiovascular risk profile in black individuals. ABSTRACT The prevalence of hypertension in black (BL) individuals exceeds that in other racial groups. Recently, resting beat-to-beat blood pressure (BP) variability has been shown to predict cardiovascular risk and detect target organ damage better than ambulatory BP monitoring. Given the heightened risk in BL individuals, we hypothesized young BL men would exhibit augmented beat-to-beat BP variability compared with white (WH) men. Furthermore, given studies reporting reduced vasodilatation and augmented vasoconstriction in BL individuals, we hypothesized that BL men would exhibit augmented variability in total peripheral resistance (TPR). In 45 normotensive men (24 BL), beat-to-beat BP (Finometer) was measured during 10-20 min of quiet rest. Cardiac output and TPR were estimated (Modelflow method). Despite similar resting BP, BL men exhibited greater BP standard deviation (e.g. systolic BP SD; BL, 7.1 ± 2.2 mmHg; WH, 5.4 ± 1.5 mmHg; P = 0.006) compared with WH men, which was accompanied by a greater TPR SD (P = 0.003), but not cardiac output SD (P = 0.390). Other traditional measures of variability provided similar results. Histogram analysis indicated that BL men exhibited a greater percentage of cardiac cycles with BPs higher (> +10 mmHg higher) and lower (< -8 mmHg lower) than mean systolic BP compared with WH men (interaction, P

PurposeLiposomal bupivacaine demonstrated promise decreasing postoperative pain in total hip and total knee arthroplasty (THA/TKA). Some randomized trials have shown non-superior results; however, confounding variables were not accounted for in such analyses. This study attempts to determine risk factors associated with failure of pain management in patients receiving liposomal bupivacaine.MethodsPostoperative pain scores were collected following primary or revision arthroplasties between January 2016 and December 2017. Retrospective analysis of institutional total joint quality and outcomes registry was screened and patients undergoing primary or revision arthroplasties who completed a multi-modal pain management including liposomal bupivacaine were included in the study. Patients with a history of infection/deviated from the institutional pain management protocol were excluded.ResultsA total of 237 patients were included for analysis. Younger patients less than 64 years old had significantly higher pain scores between 0 and 12 h and > 24 h. Active smokers had significantly higher pain scores between 0 and 6 h and > 24 h. Patients with a history of opioid use/pain management had significantly higher pain scores at 6-12 h and 24-48 h. Regression analysis indicated risk factors for resistance to liposomal bupivacaine are younger patients less than 64 years old, those undergoing primary THA, and patients with a history of smoking/pain management/opioid use.ConclusionWe identify risk factors for resistance to liposomal bupivacaine, which include younger age less than 64 years old, history of smoking/pain management/opioid use. Future studies should use these risk factors as exclusion criteria when using liposomal bupivacaine or initiating any randomized trials regarding efficacy.