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Small cell lung cancer (SCLC) remains a lethal disease with a dismal overall survival rate of 6% despite promising responses to upfront combination chemotherapy. The key drivers of such rapid mortality include early metastatic dissemination in the natural course of the disease and the near guaranteed emergence of chemoresistant disease. Here, we found that we could model the regression and relapse seen in clinical SCLC in vitro. We utilized time-course resolved RNA-sequencing to globally profile transcriptome changes as SCLC cells responded to a combination of cisplatin and etoposide-the standard-of-care in SCLC. Comparisons across time points demonstrated a distinct transient transcriptional state resembling embryonic diapause. Differential gene expression analysis revealed that expression of the PEA3 transcription factors ETV4 and ETV5 were transiently upregulated in the surviving fraction of cells which we determined to be necessary for efficient clonogenic expansion following chemotherapy. The FGFR-PEA3 signaling axis guided the identification of a pan-FGFR inhibitor demonstrating in vitro and in vivo efficacy in delaying progression following combination chemotherapy, observed inhibition of phosphorylation of the FGFR adaptor FRS2 and corresponding downstream MAPK and PI3K-Akt signaling pathways. Taken together, these data nominate PEA3 transcription factors as key mediators of relapse progression in SCLC and identify a clinically actionable small molecule candidate for delaying relapse of SCLC.

In budding yeast, the Rho-family GTPase Cdc42 has several functions that depend on its subcellular localization and the cell cycle stage. During bud formation, Cdc42 localizes to the plasma membrane at the bud tip and bud neck where it carries out functions in actin polymerization, spindle positioning, and exocytosis to ensure proper polarity development. Recent live-cell imaging analysis revealed a novel localization of Cdc42 to a discrete intracellular focus associated with the vacuole and nuclear envelope. The discovery of this novel Cdc42 localization led to the identification of a new function in ESCRT-mediated nuclear envelope sealing. However, other aspects of this intracellular localization and its functional implications were not explored. Here, we further characterize the Cdc42 focus and present several novel observations that suggest possible additional Cdc42 functions at the nucleus, including nucleus-vacuole junction formation, nuclear envelope tethering, nuclear migration, and nucleopodia formation.

Small GTPases of the Rho family are binary molecular switches that regulate a variety of processes including cell migration and oriented cell divisions. Known Cdc42 effectors include proteins involved in cytoskeletal remodeling and kinase-dependent transcription induction, but none are involved in the maintenance of nuclear envelope integrity or ER morphology. Maintenance of nuclear envelope integrity requires the EndoSomal Complexes Required for Transport (ESCRT) proteins, but how they are regulated in this process remains unknown. Here, we show by live-cell imaging a novel Cdc42 localization with ESCRT proteins at sites of nuclear envelope and ER fission and, by genetic analysis of cdc42 mutant yeast, uncover a unique Cdc42 function in regulation of ESCRT proteins at the nuclear envelope and sites of ER tubule fission. Our findings implicate Cdc42 in nuclear envelope sealing and ER remodeling, where it regulates ESCRT disassembly to maintain nuclear envelope integrity and proper ER architecture.

Objective We evaluated if venous thromboembolism (VTE) prophylaxis in the inpatient antepartum period was associated with wound hematomas, VTE occurrence, and other adverse outcomes. Study Design This study is a secondary analysis of a retrospective cohort of patients who delivered at University of Alabama at Birmingham (UAB). Patients receiving outpatient anticoagulation (AC) were excluded. We grouped patients into those who received inpatient antepartum prophylactic AC and those who did not. The primary outcome was wound hematomas from delivery to 6 weeks postpartum (PP). Secondary outcomes included VTE occurrence and select adverse outcomes, including other wound complications, unplanned procedures, mode of anesthesia, and intensive care unit (ICU) admission. Analyses were performed with no AC group as the reference. A sensitivity analysis excluding those who received inpatient PP AC was performed. Results Of 1,035 included patients, only 169 patients received inpatient prophylactic AC. They were older, had higher body mass indices, and more comorbidities. Patients receiving inpatient antepartum AC had higher wound hematomas (adjusted odds ratio [aOR] 23.81; 95% confidence interval [CI] 7.04–80.47). They had similar risk for developing VTE as the control group (aOR 2.68; 95% CI 0.19–37.49) but were more likely to have wound complications (aOR 2.36; 95% CI 1.24–4.47), maternal deaths (p < 0.05), and require PP ICU admission (aOR 13.38; 95% CI 4.79–37.35). When excluding those receiving any PP AC, there was no difference in bleeding complications between the two groups and VTE rates remained unchanged. Rates of maternal deaths and PP ICU admissions remained higher in those who received inpatient antepartum AC prophylaxis. Conclusion In this small cohort study, increased wound hematomas were found in those who received inpatient antepartum AC prophylaxis with no difference in VTE occurrence. While adverse events were increased in the inpatient AC group, this was mostly associated with PP AC prophylaxis. Larger studies should be conducted to describe the true benefits and risks of antepartum AC prophylaxis and determine efficacy of this widely used practice. Key Points Peripartum chemoprophylaxis is associated with increased wound hematomas. VTE is rare, despite its association with significant peripartum morbidity/mortality. Large studies are needed to guide practices that optimize the risk/benefit ratio of chemoprophylaxis. [ABSTRACT FROM AUTHOR]

BackgroundTranscatheter aortic valve replacement (TAVR) has recently been shown to be equivalent to surgical aortic valve replacement (SAVR) in intermediate-risk patients. As TAVR expands towards the traditionally SAVR population, TAVR versus SAVR durability becomes increasingly important. While the durability of TAVR is unknown, valve design - particularly with regards to leaflet stress - impacts on valve durability. Although leaflet stress cannot be measured directly, it can be determined using finite element modeling, with such models requiring the mechanical properties of the leaflets. Balloon-expandable TAVR involves the use of bovine pericardial leaflets treated in the same manner as surgical bioprosthetic leaflets. The study aim was to determine the leaflet mechanical properties of Carpentier-Edwards bioprostheses for future TAVR and SAVR computational models.MethodsA total of 35 leaflets were excised from 12 Carpentier-Edwards Model 3000TFX Perimount Magna aortic bioprostheses (21 mm, 23 mm, and 25 mm) and subjected to displacement-controlled equibiaxial stretch testing. The stress-strain data acquired were fitted to a Fung constitutive model to describe the material properties in circumferential and radial directions. Leaflet stiffness was calculated at specified physiological stress, corresponding to zero pressure, systemic pressure, and between zero and systemic pressure.ResultsThe 21-mm bioprostheses had significantly thinner leaflets than the larger bioprostheses. A non-linear stress-strain relationship was observed in all leaflets along the circumferential and radial directions. No significant difference in leaflet stiffness at systemic pressure, or between zero and systemic pressure, was found among the three bioprosthesis sizes. However, the leaflets from the 23 mm bioprosthesis were significantly more compliant than those of the 21 mm and 25 mm bioprostheses at zero pressure in the circumferential direction. No differences were observed in leaflet stiffness in circumferential versus radial directions.ConclusionsThe bovine pericardial leaflets from Carpentier-Edwards Perimount Magna bioprostheses showed no differences in material properties among different valve sizes at systemic pressure. The thinner 21 mm leaflets did not show any corresponding differences in leaflet stiffness, which suggests that the thinner TAV leaflets may have a similar stiffness to their thicker SAV counterparts.

Key Points: Question: Among patients with increased risk of postpartum venous thromboembolism, does a more selective protocol for initiating postpartum enoxaparin, compared with a standard risk-stratified protocol, decrease wound complications without increasing patient risk of venous thromboembolism? Findings: In this retrospective observational study, a more selective protocol for chemoprophylaxis resulted in a decrease in heparin (enoxaparin) administration (16% vs 8%). The selective protocol for postpartum enoxaparin was associated with a decrease in wound hematoma (0.7% vs 0.3% in the selective protocol group; adjusted odds ratio, 0.38; 95% CI, 0.21-0.67) without evidence of increase in venous thromboembolism (0.1% vs 0.1% in the selective protocol group; adjusted odds ratio, 0.40; 95% CI, 0.12-1.36). Meaning: A more selective protocol for postpartum enoxaparin was associated with decreased rates of wound hematomas without evidence of increased rates of postpartum thromboembolic events. Importance: In 2016, our institution adopted a pregnancy-related venous thromboembolism (VTE) prophylaxis protocol based on American College of Obstetricians and Gynecologists guidelines that recommended postpartum heparin-based chemoprophylaxis (enoxaparin) based on a risk-stratified algorithm. In response to increased wound hematomas without significant reduction in VTE using this protocol, a more selective risk-stratified approach was adopted in 2021. Objective: To evaluate outcomes of the more selective risk-stratified approach to heparin-based obstetric thromboprophylaxis (enoxaparin) protocol. Design, Setting, and Participants: Retrospective observational study of 17 489 patients who delivered at a single tertiary care center in the southeast US between January 1, 2016, and December 31, 2018 (original protocol), and between December 1, 2021, and May 31, 2023 (more selective protocol). Patients receiving outpatient anticoagulation for active VTE or high VTE risk during pregnancy were excluded. Exposure: Standard risk-stratified and more selective postpartum VTE chemoprophylaxis protocols. Main Outcomes and Measures: The primary outcome was clinical diagnosis of wound hematoma up to 6 weeks pos tpartum. The secondary outcome was new diagnosis of VTE up to 6 weeks post partum. We compared baseline characteristics and outcomes between groups and estimated adjusted odds ratios with 95% CIs of primary and secondary outcomes using the original protocol group as reference. Results: Of 17 489 patients included in the analysis, 12 430 (71%) were in the original protocol group and 5029 (29%) were in the more selective group. Rates of chemoprophylaxis decreased from 16% (original protocol) to 8% (more selective protocol). Patients in the more selective group were more likely to be older, be married, and have obesity or other comorbidities (hypertension, diabetes, cardiac disease). Compared with the original protocol, the more selective protocol was associated with a decrease in any wound hematoma (0.7% vs 0.3%; adjusted odds ratio [aOR], 0.38; 95% CI, 0.21-0.67), specifically due to a lower rate of superficial wound hematomas (0.6% vs 0.3%; aOR, 0.43; 95% CI, 0.24-0.75). There was no significant increase in VTE or individual types of VTE (0.1% vs 0.1%; aOR, 0.40; 95% CI, 0.12-1.36). Conclusions and Relevance: A more selective risk-stratified approach to an enoxaparin thromboprophylaxis protocol for VTE was associated with decreased rates of wound hematomas without increased rates of postpartum VTE. This observational study assesses incidence of wound hematoma diagnoses up to 6 weeks post partum among obstetric patients who received thromboprophylaxis according to less selective vs more selective hospital chemoprophylaxis protocols. [ABSTRACT FROM AUTHOR]

Introduction: There is significant public health interest towards providing medical care at mass-gathering events. Furthermore, mass gatherings have the potential to have a detrimental impact on the availability of already-limited municipal Emergency Medical Services (EMS) resources. This study presents a cross-sectional descriptive analysis to report broad trends regarding patients who were transported from National Collegiate Athletic Association (NCAA) Division 1 collegiate football games at a major public university in order to better inform emergency preparedness and resource planning for mass gatherings. Methods: Patient care reports (PCRs) from ambulance transports originating from varsity collegiate football games at the University of Minnesota across six years were examined. Pertinent information was abstracted from each PCR. Results: Across the six years of data, there were a total of 73 patient transports originating from NCAA collegiate football games: 45.2% (n = 33) were male, and the median age was 22 years. Alcohol-related chief complaints were involved in 50.7% (n = 37) of transports. In total, 31.5% of patients had an initial Glasgow Coma Scale (GCS) of less than 15. The majority (65.8%; n = 48; 0.11 per 10,000 attendees) were transported by Basic Life Support (BLS) ambulances. The remaining patients (34.2%; n = 25; 0.06 per 10,000 attendees) were transported by Advanced Life Support (ALS) ambulances and were more likely to be older, have abnormal vital signs, and have a lower GCS. Conclusions: This analysis of ambulance transports from NCAA Division 1 collegiate football games emphasizes the prevalence of alcohol-related chief complaints, but also underscores the likelihood of more life-threatening conditions at mass gatherings. These results and additional research will help inform emergency preparedness at mass-gathering events. [ABSTRACT FROM AUTHOR]