A Variant Mimicking Hyperphosphorylated 4E-BP Inhibits Protein Synthesis in a Sea Urchin Cell-Free, Cap-Dependent Translation System

BACKGROUND: 4E-BP is a translational inhibitor that binds to eIF4E to repress cap-dependent translation initiation. This critical protein:protein interaction is regulated by the phosphorylation of 4E-BP. Hypophosphorylated 4E-BP binds to eIF4E and inhibits cap-dependent translation, whereas hyperphosphorylated forms do not. While three 4E-BP proteins exist in mammals, only one gene encoding for 4E-BP is present in the sea urchin genome. The protein product has a highly conserved core domain containing the eIF4E-binding domain motif (YxxxxLPhi) and four of the regulatory phosphorylation sites. METHODOLOGY/PRINCIPAL FINDINGS: Using a sea urchin cell-free cap-dependent translation system prepared from fertilized eggs, we provide the first direct evidence that the sea urchin 4E-BP inhibits cap-dependent translation. We show here that a sea urchin 4E-BP variant, mimicking phosphorylation on four core residues required to abrogate binding to eIF4E, surprisingly maintains physical association to eIF4E and inhibits protein synthesis. CONCLUSIONS/SIGNIFICANCE: Here, we examine the involvement of the evolutionarily conserved core domain and phosphorylation sites of sea urchin 4E-BP in the regulation of eIF4E-binding. These studies primarily demonstrate the conserved activity of the 4E-BP translational repressor and the importance of the eIF4E-binding domain in sea urchin. We also show that a variant mimicking hyperphosphorylation of the four regulatory phosphorylation sites common to sea urchin and human 4E-BP is not sufficient for release from eIF4E and translation promotion. Therefore, our results suggest that there are additional mechanisms to that of phosphorylation at the four critical sites of 4E-BP that are required to disrupt binding to eIF4E

Device-Related Thrombus After Left Atrial Appendage Closure

Although left atrial appendage closure (LAAC) has proved non-inferior to oral anticoagulants in patients with AF, there has been recent concern about the occurrence of late complications, especially device-related thrombus (DRT), which was associated with increased risk of stroke. In this article, the incidence, risk factors and time course of DRT after LAAC are discussed, as well as the potential benefits of dedicated strategies in the management of DRT, which remain speculative, especially in patients with a contraindication to oral anticoagulants. In these patients, decision-making should be based on a multidisciplinary evaluation of the ischaemic/bleeding balance on an individual basis

0400: Degenerative calcific mitral stenosis in patients referred for high surgical risk aortic stenosis: detection and quantification by multi-detector computed tomography

BackgroundMitral annular calcifications (MAC) is a common finding in elder patients referred for transcatheter aortic valve implantation (TAVI), sometimes responsible of significant degenerative calcified mitral stenosis (CaMS), but prevalence of both is poorly defined. Multidectector computed tomography (MDCT) allows fine quantification of calcifications and is a reliable tool in rheumatic mitral stenosis, but its contribution in CaMS remains unknown. Our objective was to estimate prevalence of MAC and CaMS in patients referred for TAVI using MDCT, and determine morphological factors leading from MAC to CaMS.Methods and resultsA cohort of 346 consecutive patients referred for TAVI evaluation was screened by MDCT for MAC. One hundred and seventy four patients were positive for MAC. Among these patients, 165 patients had mitral valve area (MVA) assessable by MDCT planimetry (mean age 84 years). Analysis by segment revealed calcifications on: A1 30.9%, A2 29.1%, A3 42.4%, P1 56.4%, P2 78.8%, P3 69.7%. Mean mitral calcification volume and MVA were 1020±1398mm3 and 246±90mm 2, respectively. CaMS were severe, moderate and mild in 2.4%, 21.8% and 9.7% patients, respectively. Correlation between mitral calcification volume and MVA was significant but moderate (r=–0.433). On multivariate analysis, MVA was independently linked to mitral calcification volume, aortic annular area and specific patterns of mitral leaflet calcification underlining the role of A2 (AUC 0.81). Interobserver reproducibility of MVA was high (ICC 0.935).ConclusionsMDCT allows detailed assessment of MAC in TAVI populations, demonstrating high prevalence, and quantification of CaMS with high reproducibility. Mitral analysis should become routine during MDCT screening before TAVI as it may significantly alter the therapeutic strategy

Impact of Degree of Commissural Opening After Percutaneous Mitral Commissurotomy on Long-Term Outcome

ObjectivesWe sought to evaluate the prognostic value of the degree of commissural opening (CO) on outcome.BackgroundCommissural opening is the main mechanism by which the mitral valve area (MVA) increases after percutaneous mitral commissurotomy (PMC) but its impact on long-term outcome has never been evaluated.MethodsOf 1,024 consecutive patients with severe MS who underwent PMC, degree of CO was prospectively evaluated in 875 patients (age 48 ± 13 years, female 83%, New York Heart Association (NYHA) functional class III/IV 75%) with good immediate PMC results (MVA ≥1.5 cm2 and no mitral regurgitation >2/4). These 875 patients were divided into 3 groups: both commissures only partially opened or not split (Group 1, n = 189), 1 commissure completely split (Group 2; n = 459), and both commissures completely split (Group 3; n = 227). During a follow-up of 55 ± 28 months, following clinical end points were collected: death, cardiovascular death, need for mitral valve surgery or repeat dilation, and NYHA functional class.ResultsBefore PMC, patients in Group 1 were older, more often in NYHA functional class III/IV, but MVA and mean gradient were not different (p ≥ 0.50). Immediately after PMC, there were significant differences between groups with regard to mean gradient (Group 1, 5.1 ± 2.1 mm Hg; Group 2, 4.5 ± 1.7 mm Hg; Group 3, 4.0 ± 1.6 mm Hg; p < 0.0001) and MVA (Group 1, 1.8 ± 0.2 cm2; Group 2, 1.9 ± 0.2 cm2; Group 3, 2.1 ± 0.3 cm2; p < 0.0001). The 10-year rate of good functional results (survival without need for mitral surgery or repeat dilation and NYHA functional class I or II at last follow-up) was significantly higher in Group 3 (76 ± 5%) than in Groups 1 and 2 (39 ± 8% and 57 ± 11%, respectively; p < 0.0001). In multivariable analysis, either the degree of CO or the MVA was an independent predictor of good late functional results (p < 0.05).ConclusionsComplete CO is associated with larger MVA, smaller gradients, and functional improvement. The degree of CO provides important prognostic information and thus should be systematically evaluated during and after PMC and considered as a complementary measure of the procedural success in addition to the MVA, not always easy to assess

The genomic repertoire for cell cycle control and DNA metabolism in S. purpuratus

A search of the Strongylocentrotus purpuratus genome for genes associated with cell cycle control and DNA metabolism shows that the known repertoire of these genes is conserved in the sea urchin, although with fewer family members represented than in vertebrates, and with some cases of echinoderm-specific gene diversifications. For example, while homologues of the known cyclins are mostly encoded by single genes in S. purpuratus (unlike vertebrates, which have multiple isoforms), there are additional genes encoding novel cyclins of the B and K/L types. Almost all known cyclin-dependent kinases (CDKs) or CDK-like proteins have an orthologue in S. purpuratus; CDK3 is one exception, whereas CDK4 and 6 are represented by a single homologue, referred to as CDK4. While the complexity of the two families of mitotic kinases, Polo and Aurora, is close to that found in the nematode, the diversity of the NIMA-related kinases (NEK proteins) approaches that of vertebrates. Among the nine NEK proteins found in S. purpuratus, eight could be assigned orthologues in vertebrates, whereas the ninth is unique to sea urchins. Most known DNA replication, DNA repair and mitotic checkpoint genes are also present, as are homologues of the pRB (two) and p53 (one) tumor suppressors. Interestingly, the p21/p27 family of CDK inhibitors is represented by one homologue, whereas the INK4 and ARF families of tumor suppressors appear to be absent, suggesting that these evolved only in vertebrates. Our results suggest that, while the cell cycle control mechanisms known from other animals are generally conserved in sea urchin, parts of the machinery have diversified within the echinoderm lineage. The set of genes uncovered in this analysis of the S. purpuratus genome should enhance future research on cell cycle control and developmental regulation in this model

Clinicopathological evaluation of chronic traumatic encephalopathy in players of American football

IMPORTANCE: Players of American football may be at increased risk of long-term neurological conditions, particularly chronic traumatic encephalopathy (CTE). OBJECTIVE: To determine the neuropathological and clinical features of deceased football players with CTE. DESIGN, SETTING, AND PARTICIPANTS: Case series of 202 football players whose brains were donated for research. Neuropathological evaluations and retrospective telephone clinical assessments (including head trauma history) with informants were performed blinded. Online questionnaires ascertained athletic and military history. EXPOSURES: Participation in American football at any level of play. MAIN OUTCOMES AND MEASURES: Neuropathological diagnoses of neurodegenerative diseases, including CTE, based on defined diagnostic criteria; CTE neuropathological severity (stages I to IV or dichotomized into mild [stages I and II] and severe [stages III and IV]); informant-reported athletic history and, for players who died in 2014 or later, clinical presentation, including behavior, mood, and cognitive symptoms and dementia. RESULTS: Among 202 deceased former football players (median age at death, 66 years [interquartile range, 47-76 years]), CTE was neuropathologically diagnosed in 177 players (87%; median age at death, 67 years [interquartile range, 52-77 years]; mean years of football participation, 15.1 [SD, 5.2]), including 0 of 2 pre–high school, 3 of 14 high school (21%), 48 of 53 college (91%), 9 of 14 semiprofessional (64%), 7 of 8 Canadian Football League (88%), and 110 of 111 National Football League (99%) players. Neuropathological severity of CTE was distributed across the highest level of play, with all 3 former high school players having mild pathology and the majority of former college (27 [56%]), semiprofessional (5 [56%]), and professional (101 [86%]) players having severe pathology. Among 27 participants with mild CTE pathology, 26 (96%) had behavioral or mood symptoms or both, 23 (85%) had cognitive symptoms, and 9 (33%) had signs of dementia. Among 84 participants with severe CTE pathology, 75 (89%) had behavioral or mood symptoms or both, 80 (95%) had cognitive symptoms, and 71 (85%) had signs of dementia. CONCLUSIONS AND RELEVANCE: In a convenience sample of deceased football players who donated their brains for research, a high proportion had neuropathological evidence of CTE, suggesting that CTE may be related to prior participation in football.This study received support from NINDS (grants U01 NS086659, R01 NS078337, R56 NS078337, U01 NS093334, and F32 NS096803), the National Institute on Aging (grants K23 AG046377, P30AG13846 and supplement 0572063345-5, R01 AG1649), the US Department of Defense (grant W81XWH-13-2-0064), the US Department of Veterans Affairs (I01 CX001038), the Veterans Affairs Biorepository (CSP 501), the Veterans Affairs Rehabilitation Research and Development Traumatic Brain Injury Center of Excellence (grant B6796-C), the Department of Defense Peer Reviewed Alzheimer’s Research Program (grant 13267017), the National Operating Committee on Standards for Athletic Equipment, the Alzheimer’s Association (grants NIRG-15-362697 and NIRG-305779), the Concussion Legacy Foundation, the Andlinger Family Foundation, the WWE, and the NFL

Transcatheter valve implantation for patients with aortic stenosis: a position statement from the European Association of Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI)

Aims: To critically review the available transcatheter aortic valve implantation techniques and their results, as well as propose recommendations for their use and development. Methods and results: A committee of experts including European Association of Cardio-Thoracic Surgery and European Society of Cardiology representatives met to reach a consensus based on the analysis of the available data obtained with transcatheter aortic valve implantation and their own experience. The evidence suggests that this technique is feasible and provides haemodynamic and clinical improvement for up to 2 years in patients with severe symptomatic aortic stenosis at high risk or with contraindications for surgery. Questions remain mainly concerning safety and long-term durability, which have to be assessed. Surgeons and cardiologists working as a team should select candidates, perform the procedure, and assess the results. Today, the use of this technique should be restricted to high-risk patients or those with contraindications for surgery. However, this may be extended to lower risk patients if the initial promise holds to be true after careful evaluation. Conclusion: Transcatheter aortic valve implantation is a promising technique, which may offer an alternative to conventional surgery for high-risk patients with aortic stenosis. Today, careful evaluation is needed to avoid the risk of uncontrolled diffusio