Survey Finds Gender Disparities Impact Both Women Mentors and Mentees in Gastroenterology.

INTRODUCTION: Gastroenterologists at all levels of practice benefit from formal mentoring. Much of the current literature on mentoring in gastroenterology is based on expert opinion rather than data. In this study, we aimed to identify gender-related barriers to successful mentoring relationships from the mentor and mentee perspectives. METHODS: A voluntary, web-based survey was distributed to physicians at 20 academic institutions across the United States. Overall, 796 gastroenterology fellows and faculty received the survey link, with 334 physicians responding to the survey (42% response rate), of whom 299 (90%; 129 women and 170 men) completed mentorship questions and were included in analysis. RESULTS: Responses of women and men were compared. Compared with men, more women preferred a mentor of the same gender (38.6% women vs 4.2% men, P < 0.0001) but less often had one (45.5% vs 70.2%, P < 0.0001). Women also reported having more difficulty finding a mentor (44.4% vs 16.0%, P < 0.0001) and more often cited inability to identify a mentor of the same gender as a contributing factor (12.8% vs 0.9%, P = 0.0004). More women mentors felt comfortable advising women mentees about work-life balance (88.3% vs 63.8%, P = 0.0005). Nonetheless, fewer women considered themselves effective mentors (33.3% vs 52.6%, P = 0.03). More women reported feeling pressured to mentor because of their gender (39.5% vs 0.9% of men, P < 0.0001). Despite no gender differences, one-third of respondents reported negative impact of the COVID-19 pandemic on their ability to mentor and be mentored. DISCUSSION: Inequities exist in the experiences of women mentees and mentors in gastroenterology, which may affect career advancement and job satisfaction.

Magnetic Sphincter Augmentation Superior to Proton Pump Inhibitors for Regurgitation in a 1-Year Randomized Trial.

BACKGROUND & AIMS: Regurgitative gastroesophageal reflux disease (GERD) refractive to medical treatment is common and caused by mechanical failure of the anti-reflux barrier. We compared the effects of magnetic sphincter augmentation (MSA) with those of proton-pump inhibitors (PPIs) in a randomized trial. METHODS: Patients with moderate to severe regurgitation (assessed by the foregut symptom questionnaire) despite once-daily PPI therapy (n = 152) were randomly assigned to groups given twice-daily PPIs (n = 102) or laparoscopic MSA (n = 50) at 20 sites, from July 2015 through February 2017. Patients answered questions from the foregut-specific reflux disease questionnaire and GERD health-related quality of life survey about regurgitation, heartburn, dysphagia, bloating, diarrhea, flatulence, and medication use, at baseline and 6 and 12 months after treatment. Six months after PPI therapy, MSA was offered to patients with persistent moderate to severe regurgitation and excess reflux episodes during impedance or pH testing on medication. Regurgitation, foregut scores, esophageal acid exposure, and adverse events were evaluated at 1 year. RESULTS: Patients in the MSA group and those who crossed over to the MSA group after PPI therapy (n = 75) had similar outcomes. MSA resulted in control of regurgitation in 72/75 patients (96%); regurgitation control was independent of preoperative response to PPIs. Only 8/43 patients receiving PPIs (19%) reported control of regurgitation. Among the 75 patients who received MSA, 61 (81%) had improvements in GERD health-related quality of life improvement scores (greater than 50%) and 68 patients (91%) discontinued daily PPI use. Proportions of patients with dysphagia decreased from 15% to 7% (P < .005), bloating decreased from 55% to 25%, and esophageal acid exposure time decreased from 10.7% to 1.3% (P < .001) from study entry to 1-year after MSA (Combined P < .001). Seventy percent (48/69) of patients had pH normalization at study completion. MSA was not associated with any peri-operative events, device explants, erosions, or migrations. CONCLUSIONS: In a prospective study, we found MSA to reduce regurgitation in 95% of patients with moderate to severe regurgitation despite once-daily PPI therapy. MSA is superior to twice-daily PPIs therapy in reducing regurgitation. Relief of regurgitation is sustained over 12 months. ClinicalTrials.gov no: NCT02505945.

ASGE EndoVators Summit: simulators and the future of endoscopic training.

Interest in the use of simulation for acquiring, maintaining, and assessing skills in GI endoscopy has grown over the past decade, as evidenced by recent American Society for Gastrointestinal Endoscopy (ASGE) guidelines encouraging the use of endoscopy simulation training and its incorporation into training standards by a key accreditation organization. An EndoVators Summit, partially supported by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) of the National Institutes of Health, (NIH) was held at the ASGE Institute for Training and Technology from November 19 to 20, 2017. The summit brought together over 70 thought leaders in simulation research and simulator development and key decision makers from industry. Proceedings opened with a historical review of the role of simulation in medicine and an outline of priority areas related to the emerging role of simulation training within medicine broadly. Subsequent sessions addressed the summit's purposes: to review the current state of endoscopy simulation and the role it could play in endoscopic training, to define the role and value of simulators in the future of endoscopic training and to reach consensus regarding priority areas for simulation-related education and research and simulator development. This white paper provides an overview of the central points raised by presenters, synthesizes the discussions on the key issues under consideration, and outlines actionable items and/or areas of consensus reached by summit participants and society leadership pertinent to each session. The goal was to provide a working roadmap for the developers of simulators, the investigators who strive to define the optimal use of endoscopy-related simulation and assess its impact on educational outcomes and health care quality, and the educators who seek to enhance integration of simulation into training and practice.

Laparoscopic magnetic sphincter augmentation versus double-dose proton pump inhibitors for management of moderate-to-severe regurgitation in GERD: a randomized controlled trial.

BACKGROUND AND AIMS: GERD patients frequently complain of regurgitation of gastric contents. Medical therapy with proton-pump inhibitors (PPIs) is frequently ineffective in alleviating regurgitation symptoms, because PPIs do nothing to restore a weak lower esophageal sphincter. Our aim was to compare effectiveness of increased PPI dosing with laparoscopic magnetic sphincter augmentation (MSA) in patients with moderate-to-severe regurgitation despite once-daily PPI therapy. METHODS: One hundred fifty-two patients with GERD, aged ≥21 years with moderate-to-severe regurgitation despite 8 weeks of once-daily PPI therapy, were prospectively enrolled at 21 U.S. sites. Participants were randomized 2:1 to treatment with twice-daily (BID) PPIs (N = 102) or to laparoscopic MSA (N = 50). Standardized foregut symptom questionnaires and ambulatory esophageal reflux monitoring were performed at baseline and at 6 months. Relief of regurgitation, improvement in foregut questionnaire scores, decrease in esophageal acid exposure and reflux events, discontinuation of PPIs, and adverse events were the measures of efficacy. RESULTS: Per protocol, 89% (42/47) of treated patients with MSA reported relief of regurgitation compared with 10% (10/101) of the BID PPI group (P < .001) at the 6-month primary endpoint. By intention-to-treat analysis, 84% (42/50) of patients in the MSA group and 10% (10/102) in the BID PPI group met this primary endpoint (P < .001). Eighty-one percent (38/47) of patients with MSA versus 8% (7/87) of patients with BID PPI had ≥50% improvement in GERD-health-related quality of life scores (P < .001), and 91% (43/47) remained off of PPI therapy. A normal number of reflux episodes and acid exposures was observed in 91% (40/44) and 89% (39/44) of MSA patients, respectively, compared with 58% (46/79) (P < .001) and 75% (59/79) (P = .065) of BID PPI patients at 6 months. No significant safety issues were observed. In MSA patients, 28% reported transient dysphagia; 4% reported ongoing dysphagia. CONCLUSION: Patients with GERD with moderate-to-severe regurgitation, especially despite once-daily PPI treatment, should be considered for minimally invasive treatment with MSA rather than increased PPI therapy. (Clinical trial registration number: NCT02505945.).

A pharmacokinetic-pharmacodynamic model predicting tumour growth inhibition after intermittent administration with the mTOR kinase inhibitor AZD8055.

BACKGROUND AND PURPOSE: AZD8055 is a potent orally available mTOR kinase inhibitor with in vitro and in vivo antitumour activity against a range of tumour types. Preclinical studies showed that AZD8055 induced a dose-dependent pharmacodynamic effect in xenograft models in vivo, but a lack of understanding of the relative contributions of the maximum inhibition of the biomarkers and the duration of inhibition to the antitumour effect, limited the rational design of experiments to optimize the dose and schedules of treatment. EXPERIMENTAL APPROACH: In this study, a mathematical modelling approach was developed to relate pharmacodynamics and antitumour activity using preclinical data generated in mice bearing U87-MG xenografts. KEY RESULTS: Refinement and validation of the model was carried out in a panel of additional human tumour xenograft models with different growth rates and different sensitivity to AZD8055 (from partial growth inhibition to regression). Finally, the model was applied to accurately predict the efficacy of high, intermittent dosing schedules of AZD8055. CONCLUSIONS AND IMPLICATIONS: Overall, this new model linking pharmacokinetics, pharmacodynamic biomarkers and efficacy across several tumour xenografts with different sensitivity to AZD8055 was able to identify the optimal dose and route of administration to maximize the antitumour efficacy in preclinical models and its potential for translation into man.

Diffusion of Immunoglobulin G in Shed Vaginal Epithelial Cells and in Cell-Free Regions of Human Cervicovaginal Mucus.

Human cervicovaginal mucus (CVM) is a viscoelastic gel containing a complex mixture of mucins, shed epithelial cells, microbes and macromolecules, such as antibodies, that together serve as the first line of defense against invading pathogens. Here, to investigate the affinity between IgG and different mucus constituents, we used Fluorescence Recovery After Photobleaching (FRAP) to measure the diffusion of IgG in fresh, minimally modified CVM. We found that CVM exhibits substantial spatial variations that necessitate careful selection of the regions in which to perform FRAP. In portions of CVM devoid of cells, FRAP measurements using different IgG antibodies and labeling methods consistently demonstrate that both exogenous and endogenous IgG undergo rapid diffusion, almost as fast as in saline, in good agreement with the rapid diffusion of IgG in mid-cycle endocervical mucus that is largely devoid of cells. This rapid diffusion indicates the interactions between secreted mucins and IgG must be very weak and transient. IgG also accumulated in cellular debris and shed epithelial cells that had become permeable to IgG, which may allow shed epithelial cells to serve as reservoirs of secreted IgG. Interestingly, in contrast to cell-free regions of CVM, the diffusion of cell-associated IgG was markedly slowed, suggesting greater affinity between IgG and cellular constituents. Our findings contribute to an improved understanding of the role of IgG in mucosal protection against infectious diseases, and may also provide a framework for using FRAP to study molecular interactions in mucus and other complex biological environments.

Understanding Protein Structure Deformation on the Surface of Gold Nanoparticles of Varying Size.

Gold nanoparticles (AuNPs) have been of recent interest due to their unique optical properties and their biocompatibility. Biomolecules spontaneously adsorb to their surface, a trait that could potentially be exploited for drug targeting. Currently, it is unclear whether protein-AuNP interactions at the nanoparticle surface are dependent on nanoparticle size. In this work, we investigate whether varying surface curvature can induce protein unfolding and multilayer binding in citrate-coated AuNPs of various sizes. A recently developed NMR-based approach was utilized to determine the adsorption capacity, and protein NMR spectra were compared to determine whether nanoparticle size influences protein interactions at the surface. In addition, transmission electron microscopy (TEM) and dynamic light scattering (DLS) were employed to corroborate the NMR studies. Over a broad range of AuNP sizes (14-86 nm), we show that adsorption capacity can be predicted by assuming that proteins are compact and globular on the nanoparticle surface. Additionally, roughly one layer of proteins is adsorbed regardless of AuNP size. Our results hold for two proteins of significantly different sizes, GB3 (6 kDa) and bovine carbonic anhydrase (BCA, 29 kDa). However, the unstable drkN SH3 domain (ΔG0 ≈ 0, 7 kDa) does not appear to follow the same trend seen for stable, globular proteins. This observation suggests that unstable proteins can deform significantly when bound to AuNP surfaces. Taken together, the results of this work can be used to improve our knowledge of the mechanism of protein-AuNP interactions to optimize their use in the biomedical field.