MFA11 (MFA 2011)

Catalogue of a culminating student exhibition held at the Mildred Lane Kemper Art Museum, May 6-Aug. 1, 2011. Content includes Introduction / Buzz Spector -- Patricia Olynyk -- Marshall N. Klimasewiski -- John Talbott Allen -- Meghan Bean -- Shira Berkowitz / Maggie Stanley Majors -- Darrick Byers, Bryce Olen Robinson -- Jisun Choi -- Zlatko Ćosić -- James R. Daniels -- Kara Daving -- Andrea Degener -- Kristin Fleischmann / Randi Shapiro -- William Frank / Lawrence Ypil -- Nicholas Kania -- Katherine McCullough -- Jordan McGirk / Aditi Machado -- Zachary Miller -- Esther Murphy / Maggie Stanley Majors -- Kathryn Neale -- Christopher Ottinger / Melissa Olson -- Maia Palmer -- Nicole Petrescu / Melissa Olson -- Lauren Pressler / Randi Shapiro -- Whitney Sage / Aliya A. Reich -- Donna Smith.https://openscholarship.wustl.edu/books/1005/thumbnail.jp

Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

: The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

Achievement of the planetary defense investigations of the Double Asteroid Redirection Test (DART) mission

NASA's Double Asteroid Redirection Test (DART) mission was the first to demonstrate asteroid deflection, and the mission's Level 1 requirements guided its planetary defense investigations. Here, we summarize DART's achievement of those requirements. On 2022 September 26, the DART spacecraft impacted Dimorphos, the secondary member of the Didymos near-Earth asteroid binary system, demonstrating an autonomously navigated kinetic impact into an asteroid with limited prior knowledge for planetary defense. Months of subsequent Earth-based observations showed that the binary orbital period was changed by –33.24 minutes, with two independent analysis methods each reporting a 1σ uncertainty of 1.4 s. Dynamical models determined that the momentum enhancement factor, β, resulting from DART's kinetic impact test is between 2.4 and 4.9, depending on the mass of Dimorphos, which remains the largest source of uncertainty. Over five dozen telescopes across the globe and in space, along with the Light Italian CubeSat for Imaging of Asteroids, have contributed to DART's investigations. These combined investigations have addressed topics related to the ejecta, dynamics, impact event, and properties of both asteroids in the binary system. A year following DART's successful impact into Dimorphos, the mission has achieved its planetary defense requirements, although work to further understand DART's kinetic impact test and the Didymos system will continue. In particular, ESA's Hera mission is planned to perform extensive measurements in 2027 during its rendezvous with the Didymos–Dimorphos system, building on DART to advance our knowledge and continue the ongoing international collaboration for planetary defense

Artist’s Statement

Mentor: Michael Byron From the Washington University Undergraduate Research Digest: WUURD, Volume 4, Issue 1, Fall 2008. Published by the Office of Undergraduate Research. Henry Biggs, Director of Undergraduate Research and Associate Dean in the College of Arts & Sciences; Joy Zalis Kiefer, Undergraduate Research Coordinator, Co-editor, and Assistant Dean in the College of Arts & Sciences; Kristin Sobotka, Editor

Hepatitis B Virus Requires Intact Caveolin-1 Function for Productive Infection in HepaRG Cells

International audienceInvestigation of the entry pathways of hepatitis B virus (HBV), a member of the family Hepadnaviridae , has been hampered by the lack of versatile in vitro infectivity models. Most concepts of hepadnaviral infection come from the more robust duck HBV system; however, whether the two viruses use the same mechanisms to invade target cells is still a matter of controversy. In this study, we investigate the role of an important plasma membrane component, caveolin-1 (Cav-1), in HBV infection. Caveolins are the main structural components of caveolae, plasma membrane microdomains enriched in cholesterol and sphingolipids, which are involved in the endocytosis of numerous ligands and complex signaling pathways within the cell. We used the HepaRG cell line permissive for HBV infection to stably express dominant-negative Cav-1 and dynamin-2, a GTPase involved in vesicle formation at the plasma membrane and other organelles. The endocytic properties of the newly established cell lines, designated HepaRG Cav-1 , HepaRG Cav-1Δ1-81 , HepaRG Dyn-2 , and HepaRG Dyn-2K44A , were validated using specific markers for different entry routes. The cells maintained their properties during cell culture, supported differentiation, and were permissive for HBV infection. The levels of both HBV transcripts and antigens were significantly decreased in cells expressing the mutant proteins, while viral replication was not directly affected. Chemical inhibitors that specifically inhibit clathrin-mediated endocytosis had no effect on HBV infection. We concluded that HBV requires a Cav-1-mediated entry pathway to initiate productive infection in HepaRG cells

Hepatitis B Virus Requires Intact Caveolin-1 Function for Productive Infection in HepaRG Cells▿

Investigation of the entry pathways of hepatitis B virus (HBV), a member of the family Hepadnaviridae, has been hampered by the lack of versatile in vitro infectivity models. Most concepts of hepadnaviral infection come from the more robust duck HBV system; however, whether the two viruses use the same mechanisms to invade target cells is still a matter of controversy. In this study, we investigate the role of an important plasma membrane component, caveolin-1 (Cav-1), in HBV infection. Caveolins are the main structural components of caveolae, plasma membrane microdomains enriched in cholesterol and sphingolipids, which are involved in the endocytosis of numerous ligands and complex signaling pathways within the cell. We used the HepaRG cell line permissive for HBV infection to stably express dominant-negative Cav-1 and dynamin-2, a GTPase involved in vesicle formation at the plasma membrane and other organelles. The endocytic properties of the newly established cell lines, designated HepaRGCav-1, HepaRGCav-1Δ1-81, HepaRGDyn-2, and HepaRGDyn-2K44A, were validated using specific markers for different entry routes. The cells maintained their properties during cell culture, supported differentiation, and were permissive for HBV infection. The levels of both HBV transcripts and antigens were significantly decreased in cells expressing the mutant proteins, while viral replication was not directly affected. Chemical inhibitors that specifically inhibit clathrin-mediated endocytosis had no effect on HBV infection. We concluded that HBV requires a Cav-1-mediated entry pathway to initiate productive infection in HepaRG cells

Impact of effective regurgitant orifice area on outcome of secondary mitral regurgitation transcatheter repair.

OBJECTIVES To assess the value of effective regurgitant orifice (ERO) in predicting outcome after edge-to-edge transcatheter mitral valve repair (TMVR) for secondary mitral regurgitation (SMR) and identify the optimal cut-off for patients' selection. METHODS Using the EuroSMR (European Registry of Transcatheter Repair for Secondary Mitral Regurgitation) registry, that included patients undergoing edge-to-edge TMVR for SMR between November 2008 and January 2019 in 8 experienced European centres, we assessed the optimal ERO threshold associated with mortality in SMR patients undergoing TMVR, and compared characteristics and outcomes of patients according to baseline ERO. RESULTS Among 1062 patients with severe SMR and ERO quantification by proximal isovelocity surface area method in the registry, ERO was < 0.3 cm2 in 575 patients (54.1%), who were more symptomatic at baseline (NYHA class ≥ III: 91.4% vs. 86.9%, for ERO < vs. ≥ 0.3 cm2; P = 0.004). There was no difference in all-cause mortality at 2-year follow-up according to baseline ERO (28.3% vs. 30.0% for ERO < vs. ≥ 0.3 cm2, P = 0.585). Both patient groups demonstrated significant improvement of at least one NYHA class (61.7% and 73.8%, P = 0.002), resulting in a prevalence of NYHA class ≤ II at 1-year follow-up of 60.0% and 67.4% for ERO < vs. ≥ 0.3 cm2, respectively (P = 0.05). CONCLUSION All-cause mortality at 2 years after TMVR does not differ if baseline ERO is < or ≥ 0.3 cm2, and both groups exhibit relevant clinical improvements. Accordingly, TMVR should not be withheld from patients with ERO < 0.3 cm2 who remain symptomatic despite optimal medical treatment, if TMVR appropriateness was determined by experienced teams in dedicated valve centres

Impact of Proportionality of Secondary Mitral Regurgitation on Outcome After Transcatheter Mitral Valve Repair

OBJECTIVES The purpose of this paper was to evaluate the impact of proportionality of secondary mitral regurgitation (SMR) in a large real-world registry of transcatheter edge-to-edge mitral valve repair (TMVr) BACKGROUND Differences in the outcomes of recent randomized trials of TMVr for SMR may be explained by the proportionality of SMR severity to left ventricular (LV) volume. METHODS The ratio of pre-procedural effective regurgitant orifice area (EROA) to LV end-diastolic volume (LVEDV) was retrospectively assessed in patients undergoing TMVr for severe SMR between 2008 and 2019 from the EuroSMR registry. A recently proposed SMR proportionality scheme was adapted to stratify patients according to EROA/LVEDV ratio in 3 groups: MR-dominant (MD), MR-LV-co-dominant (MLCD), and LV-dominant (LD). All-cause mortality was assessed as a primary outcome, secondary heart failure (HF) outcomes included hospitalization for HF (HHF), New York Heart Association (NYHA) functional class, N-terminal pro-B-type natriuretic peptide (NT-proBNP), 6-min-walk distance, quality of life and MR grade. RESULTS A total of 1,016 patients with an EROA/LVEDV ratio were followed for 22 months after TMVr. MR was reduced to grade <= 2+ in 92%, 96%, and 94% of patients (for MD, MLCD, and LD, respectively; p = 0.18). After adjustment for covariates including age, sex, diabetes, kidney function, body surface area, LV ejection fraction, and procedural MR reduction (grade <= 2+), adjusted rates of 2-year mortality in MD patients did not differ from those for MLCD patients (17% vs. 18%, respectively), whereas it was higher in LD patients (23%; p = 0.02 for comparison vs. MD+MLCD). The adjusted first HHF rate differed between groups (44% in MD, 56% in MLCD, 29% in LD; p = 0.01) as did the adjusted time for first death or HHF rate (66% in MD, 82% in MLCD, 68% in LD; p = 0.02). Improvement of NYHA functional class was seen in all groups (p < 0.001). Values for 6-min-walk distances, quality of life and NT-proBNP improved in most patients. CONCLUSIONS MD and MLCD patients had a comparable, adjusted 2-year mortality rate after TMVr which was slightly better than that of LD patients. Patients treated with TMVr had symptomatic improvement regardless of EROA/LVEDV ratio. (C) 2021 by the American College of Cardiology Foundation

Sex-Related Clinical Characteristics and Outcomes of Patients Undergoing Transcatheter Edge-to-Edge Repair for Secondary Mitral Regurgitation.

OBJECTIVES The authors sought to assess sex-based differences in characteristics and outcomes of patients undergoing transcatheter edge-to-edge mitral valve repair (TMVR) for secondary mitral regurgitation (SMR). BACKGROUND Subgroup analysis from the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation) trial indicated potential sex-related differences in outcomes after TMVR. The impact of sex on results after TMVR in a real-world setting is unknown. METHODS The authors assessed clinical outcomes and echocardiographic parameters in women and men undergoing TMVR for SMR between 2008 and 2018 who were included in the large, international, multicenter real-world EuroSMR registry (European Registry of Transcatheter Repair for Secondary Mitral Regurgitation). RESULTS A total of 1,233 patients, including 445 women (36%) and 788 men (64%), were analyzed. Although women were significantly older and had fewer comorbidities than men, TMVR was equally effective in women and men (mitral regurgitation [MR] grade ≤2+ at discharge: 93.2% vs. 94.6% for women vs. men; p = 0.35). All-cause mortality at 1 year (17.9% vs. 18.9%, adjusted hazard ratio: 0.806; p = 0.46) and at 2-year follow-up (26.5% vs. 26.4%, adjusted hazard ratio: 0.757; p = 0.26) were similar in women versus men after multivariate regression analysis. Durability of MR reduction, improvement in symptoms, quality of life, and functional capacity did also not differ during follow-up. CONCLUSIONS Results from the EuroSMR registry confirmed effective and similar MR reduction with TMVR in women and men. There were no sex-related differences in clinical outcomes up to 2 years of follow-up