Citations

Significance Glioblastoma, the most common and lethal of primary brain tumors, can diffusely infiltrate brain. Because the components of the cytoskeleton that drive tumor invasion are nonredundant, they have been attractive targets for blocking glioblastoma dispersion. However, we find that while targeting one of these—the molecular motor myosin IIA—effectively blocks glioblastoma invasion, it enhances tumor proliferation and lethality. In this study, we have found that myosin IIA functions as a tumor suppressor by reducing signaling of two oncogenes—ERK1/2 and NF-κB—in a manner regulated by the mechanics of the tumor and surrounding brain. Our results also argue that effective treatment of glioblastoma will require inhibiting targets that drive both invasion and proliferation.

Purpose International health electives (IHEs) provide numerous educational benefits; potential harms are less well understood. One potential harm is trainee distress associated with increased patient death during IHEs. The purpose of this study was to explore residents’ and fellows’ IHE experiences with patient death. Method The authors used applied thematic analysis to explore residents’ and fellows’ IHE experiences with patient death. The Mayo International Health Program supports IHEs from all specialties across three Mayo Clinic sites. Data were collected and analyzed in two steps. First the authors collected, coded, and analyzed narrative reflections from 43 postrotation reports gathered in 2001–2017 and identified themes relating to experiences with patient death. Second, in 2016–2017 the authors conducted semistructured interviews with six previous participants to refine thematic analysis. Results Participants described impacts of experiencing increased patient death and identified themes in two domains: difficult experiences with patient death and potential interventions to help residents process their experiences. They identified four themes illustrating why these experiences were difficult: lack of preparation for increased exposure to death, lack of closure, consequences of limited resources, and differences in cultural beliefs regarding death. While pretrip preparation for dealing with death was viewed as important, trainees identified support during and debriefing after IHEs as additional important interventions. Conclusions Given the popularity of IHEs, residency programs should consider the effect on trainees of increased exposure to patient death. Study findings can inform IHE preparation, support, and debriefing to minimize distress associated with witnessing patient deaths on IHEs.

Abstract Currier, BS, Harty, PS, Zabriskie, HA, Stecker, RA, Moon, JM, Jagim, AR, and Kerksick, CM. Fat-free mass index in a diverse sample of male collegiate athletes. J Strength Cond Res 33(6): 1474–1479, 2019—Fat-free mass index (FFMI) is a body composition metric that has been used to assess relative muscularity in athletes. Fat-free mass index is calculated by dividing FFM by height squared, although further height corrections through linear regression may be needed in taller individuals. This study reported height-adjusted FFMI (FFMI Adj ) data in 209 male collegiate athletes from 10 sports (baseball, cross country, football, golf, ice hockey, weightlifting, rugby, swimming, track and field, and water polo) and the FFMI Adj natural upper limit for sports with sufficient sample size. The body composition of all subjects (mean ± SD ; age: 20.7 ± 1.9 years, height: 182.9 ± 6.7 cm, body mass: 90.8 ± 16.8 kg, and percent body fat: 15.6 ± 5.3) was measured using dual-energy x-ray absorptiometry. Linear regression was used to adjust for height, and the FFMI Adj natural upper limit was determined by calculating the 97.5th percentile of all values. One-way analyses of variance with Games-Howell post hoc comparisons were used to determine between-sport differences. A paired-samples t -test revealed a significant difference ( p < 0.001) between unadjusted and adjusted mean FFMI values. The overall mean FFMI Adj was 22.8 ± 2.8 kg·m −2 . Significant between-sport differences ( p < 0.001) in FFMI Adj were identified. Average FFMI Adj was highest in football athletes (24.28 ± 2.39 kg·m −2 ) and lowest in water polo athletes (20.68 ± 3.56 kg·m −2 ). The FFMI Adj upper limit was calculated for all athletes (28.32 kg·m −2 ), rugby (29.1 kg·m −2 ), and baseball (25.5 kg·m −2 ). This study reported FFMI Adj values in a diverse cohort of male collegiate athletes, providing data for the first time in several sports. These values can be used to guide nutritional and exercise interventions, predict athletic performance, and provide coaches with standardized information regarding the potential for further FFM accretion in male athletes.

AbstractIncreasing rates of chronic wound infections caused by antibiotic‐resistant bacteria are a crisis in healthcare settings. Biofilms formed by bacterial communities in these wounds create a complex environment, enabling bacteria to persist, even with antibiotic treatment. Wound infections caused by methicillin‐resistant Staphylococcus aureus (MRSA) are major causes of morbidity in clinical practice. There is a need for new therapeutic interventions not based on antibiotics. Hydrogen peroxide (H2O2) is a known antibacterial/antibiofilm agent, continuous delivery of which has been challenging. A conductive electrochemical scaffold (e‐scaffold) is developed, which is composed of carbon fabric that electrochemically reduces dissolved oxygen into H2O2 when polarized at −0.6 VAg/AgCl, as a novel antibiofilm wound dressing material. In this study, the in vitro antibiofilm activity of the e‐scaffold against MRSA is investigated. The developed e‐scaffold efficiently eradicates MRSA biofilms, based on bacterial quantitation and ATP measurements. Moreover, imaging hinted at the possibility of cell‐membrane damage as a mechanism of action. These results suggest that an H2O2‐generating e‐scaffold may be a novel platform for eliminating MRSA biofilms without using antibiotics and may be useful to treat chronic MRSA wound infections.

OBJECTIVEThe authors sought to investigate the incidence and predictors of venous thromboembolic events (VTEs) after craniotomy for tumor resection, which are not well established, and the efficacy of and risks associated with VTE chemoprophylaxis, which remains controversial.METHODSThe authors investigated the incidence of VTEs in a consecutive series of patients presenting to the authors’ institution for resection of an intracranial lesion between 2012 and 2017. Information on patient and tumor characteristics was collected and independent predictors of VTEs were determined using stepwise multivariate logistic regression analysis. Review of the literature was performed by searching MEDLINE using the keywords “venous thromboembolism,” “deep venous thrombosis,” “pulmonary embolism,” “craniotomy,” and “brain neoplasms.”RESULTSThere were 1622 patients included for analysis. A small majority of patients were female (52.6%) and the mean age of the cohort was 52.9 years (SD 15.8 years). A majority of intracranial lesions were intraaxial (59.3%). The incidence of VTEs was 3.0% and the rates of deep venous thromboses and pulmonary emboli were 2.3% and 0.9%, respectively. On multivariate analysis, increasing patient age (unit OR 1.02, 95% CI 1.00–1.05; p = 0.018), history of VTE (OR 7.26, 95% CI 3.24–16.27; p < 0.001), presence of motor deficit (OR 2.64, 95% CI 1.43–4.88; p = 0.002), postoperative intracranial hemorrhage (OR 4.35, 95% CI 1.51–12.55; p < 0.001), and prolonged intubation or reintubation (OR 3.27, 95% CI 1.28–8.32; p < 0.001) were independently associated with increased odds of a VTE. There were 192 patients who received VTE chemoprophylaxis (11.8%); the mean postoperative day of chemoprophylaxis initiation was 4.6 (SD 3.8). The incidence of VTEs was higher in patients receiving chemoprophylaxis than in patients not receiving chemoprophylaxis (8.3% vs 2.2%; p < 0.001). There were 30 instances of clinically significant postoperative hemorrhage (1.9%), with only 1 hemorrhage occurring after initiation of VTE chemoprophylaxis (0.1%).CONCLUSIONSThe study results show the incidence and predictors of VTEs after craniotomy for tumor resection in this patient population. The incidence of VTE within this cohort appears low and comparable to that observed in other institutional series, despite the lack of routine prophylactic anticoagulation in the postoperative setting.