Symptomatic vascular ring due to double aortic arch: A report of two cases.

Vascular ring anomalies, represented mainly by the double aortic arch (DAA), account for about 1% of congenital cardiovascular anomalies and are characterized by tracheoesophageal compression due to encircling vascular or ligamentous structures. These anomalies arise from the failure of the right fourth aortic arch to regress during embryonic development, leading to symptoms ranging from respiratory distress to dysphagia. Diagnostic imaging includes chest radiography, CT, MRI, and echocardiography, each with specific considerations, especially in pediatric patients. Management, often surgical, focuses on relieving compression symptoms and has a favorable prognosis. This case series emphasizes the manifestations of the double aortic arch, whether it be respiratory distress or dysphagia, and addresses both right and left dominant arches.

Promoting effect of Cu as electron transfer medium on NH3-SCO reaction in asymmetric Ag-Ov-Ti-Sm-Cu ring active site.

Selective catalytic oxidation of ammonia (NH3-SCO) has become an effective method to reduce ammonia (NH3) emissions, and is a key part to solve the problem of NH3 pollution. Nevertheless, the optimization of this technology's performance relies heavily on innovation and the development of catalyst design. In this study, a SmCuAgTiOx catalyst with an asymmetric Ag-Ov-Ti-Sm-Cu ring active site was prepared and applied to the NH3-SCO reaction. The low conversion of Cu-based catalysts in NH3 at low temperature and the inherent low N2 selectivity of Ag-based catalysts were solved. The successful creation of the asymmetric ring active site improved the catalyst's reduction performance. Additionally, Cu, acting as an electron transfer medium, plays a crucial role in enhancing electron transfer within the asymmetric ring active site, thus increasing the redox cycle of the catalyst during the reaction. In addition, some lattice oxygen is lost in the catalyst, resulting in the formation of a large number of oxygen vacancies. This process stimulates the adsorption and activation of surface-adsorbed oxygen, facilitating the conversion of NH3 to an amide (NH2) intermediate during the reaction and reducing non-selective oxidation. The N2 selectivity was improved without significantly affecting the performance of Ag-based catalyst. In-situ diffuse reflectance fourier transform infrared spectroscopy (In-situ DRIFTS) analysis reveals that the SmCuAgTiOx catalyst primarily follows an "internal" selective catalytic reduction (iSCR) mechanism in the NH3-SCO reaction, complemented by the imide mechanism. The asymmetric Ag-Ov-Ti-Sm-Cu ring active site developed in this study provides a new perspective for efficiently solving NH3 pollution in the future.

Comparison of the MIPPO technique and the modified Stoppa approach in the treatment of unstable anterior pelvic ring injuries: a retrospective cohort study.

BACKGROUND: Anterior pelvic ring injuries have gradually become common. Using a minimally invasive technique to treat this injury may be feasible if the reduction and stability can be effectively achieved. We describe a percutaneous technique, minimally invasive percutaneous plate osteosynthesis (MIPPO), to fixate the anterior pelvis via establishing a subperiosteal tunnel between two limited incisions over the iliac crest(s) and pubic ramus in this research. METHODS: A retrospective cohort study comparing the MIPPO technique (n = 60) versus the modified Stoppa approach (n = 53) for anterior pelvic ring injuries with posterior ring instability was performed from September 2016 to January 2023. The relative surgery variables, follow-up function evaluation, and complications were compared in two groups. The reduction quality of fracture was assessed according to the Matta criterion, and the functional score was evaluated using the Majeed score. RESULTS: All patients completed follow-up, with an average interval of 39.90 ± 17.53 months (range 12-78). In the MIPPO technique group, the surgery interval and blood losses were lower compared to the modified Stoppa approach group (P<0.05). The mean procedure times and intraoperative blood losses were 69.56 ± 14.04 min/side (range 50-110) and 156.23 ± 49.75 mL/side (range 90-250) for unilateral anterior ring MIPPO fixation separately. All patients got a satisfactory reduction of the fracture. In the follow-up, earlier ambulation, shorter postoperative hospital stays, and lower complication rates were observed for patients using the MIPPO technique compared to the modified Stoppa approach (P<0.05). However, there is no statistical difference in these indicators including fracture union interval, full load time, the Majeed score, patient satisfaction level, and return to pre-injured work rate between the two groups. CONCLUSION: This clinical experience gives support for the use of the MIPPO technique to stabilize the anterior pelvis. This minimally invasive technique was an effective and safe surgery method and could obtain satisfactory function results, particularly fitting to part of patients with resistance using the modified Stoppa approach.

Dendroclimatological study of ancient trees integrating non-destructive techniques.

Based on the need to protect previous ancient trees and the development of dendroclimatology, the use of non-destructive technologies in tree-ring research has gained increasing attention. This study focuses on the ancient Pinus tabulaeformis in Yu Xiang Forest Farm in Henan Province. Firstly, samples were collected using the traditional Increment borers and the Resistograph, a non-destructive method. Subsequently, the peak-valley analysis was used to filter the data obtained by the Resistograph to extract the tree ring width sequence, and the data's accuracy was verified by correlation analysis with tree ring width sequence by the Increment borers. Then, the optimal filtering method and an appropriate comprehensive threshold were determined, and tree ring width and density sequences were successfully extracted. Following that, the growth trend and residual resistance in the measurement process were corrected using linear fitting and Ensemble Empirical Mode Decomposition (EEMD) technology, thereby establishing the tree-ring width and density index series, which were further validated through correlation analysis and t-tests. Finally, analysis of the correlation with climatic factors, identified the main limiting factors for tree growth, and the accuracy of the tree-ring information extracted by the Resistograph was further verified. The results showed that spite of certain differences between the tree-ring width indices extracted by the Resistograph and the Increment borer, they were generally reliable. The radial growth of the ancient P.tabulaeformis in Yu Xiang Forest Farm is primarily influenced by temperature, with the maximum density of the tree rings responding more significantly to the mean maximum temperature, while the minimum density of the tree rings responded more significantly to the mean minimum temperature. These results not only provide a scientific and accurate age for the protection of ancient trees and verify the reliability of the data obtained by the Resistograph, but also facilitate the use of non-destructive technology for in-depth study of ancient trees, therefore enhancing our understanding of how climate change affects tree growth and provide valuable insights for the future protection and management of these ancient trees.

The Anaconda One-LokTM stent graft for the treatment of infrarenal abdominal aortic aneurysms: clinical results, technical, and mechanical characteristics.

INTRODUCTION: The Anaconda aortic stent graft is a trimodular endovascular stent graft with an active infrarenal fixation suitable for the treatment of infrarenal abdominal aortic aneurysms with an infrarenal neck angulation ≤90°. A unique magnet-based mechanism facilitates the cannulation of the contralateral leg. AREAS COVERED: The present article provides a complete description of the third-generation Anaconda endograft, the Anaconda One-LokTM, its clinical performance and the related technical and mechanical characteristics as well as a brief comparison between itself and other similar endografts. EXPERT OPINION: The Anaconda One-Lok stent graft is particularly suitable for abdominal aortic aneurysms with an infrarenal aortic neck angulation up to 90°. Issues that need to be resolved concern the higher incidence of iliac limb occlusion and distal migration compared to other commercially available endografts and possibly the valley central migration with the risk of covering the renal ostia.

Stereoselectivity Control Interplay in Racemic Lactide Polymerization by Achiral Al-Salen Complexes.

The origin of stereocontrol in ring opening polymerization (ROP) of racemic lactide (rac-LA) promoted by achiral aluminium-based catalysts has been explained through DFT calculations combined with a molecular descriptor (%VBur) and the activation strain model (ASM-NEDA) analysis. The proposed chain end control (CEC) model suggests that the ligand framework adopts a chiral configuration mimicking the enantiomorphic site control (ESC) while also incorporating control of the last inserted monomer unit. It is found that the ligand wrapping mode around the aluminium centre is dictated by the monomer configuration (R,R-LA and S,S-LA). A good correlation with experimental data is achieved only when accounting for the ligand dynamic features and its steric influences, as highlighted by %VBur steric maps and ASM-NEDA analysis. Understanding the ESC and CEC interplay is an important target for obtaining stereoselective ROP polymerization for the synthesis of biodegradable materials with tailored properties.

Advances in synthesis of novel annulated azecines and their unique pharmacological properties.

Annulated azecines, mostly partially saturated benzo[d]azecine and dibenzo[c,g]azecine fusion isomers, constitute a unique class of alkaloids and nature-inspired azaheterocyclic compounds with interesting reactivity, physicochemical and biological properties. Due to difficulties associated with the synthesis of the benzazecine (or bioisosteric) scaffold they are not the focus of organic and medicinal chemists' consideration, whereas it is worth noting the range of their pharmacological activities and their potential application in medicinal chemistry. Herein, we reviewed the synthetic methodologies of arene-fused azecine derivatives known up to date and reported about the progress in disclosing their potential in drug discovery. Indeed, their conformational restriction or liberation drives their selectivity towards diverse biological targets, making them versatile scaffolds for developing drugs, including antipsychotic and anticancer drugs, but also small molecules with potential for anti-neurodegenerative treatments, as the recent literature shows.

Resonant Ring with a Gain of 36 for Use with a 1 MW 110 GHz Gyrotron.

A 110 GHz quasi-optical ring resonator, designed for use with a 1 MW pulsed gyrotron, has been built and successfully tested using a 100 mW solid-state source. A low reflectance (2.4%) input coupler and a low-loss, four-mirror ring demonstrated a compression ratio, defined as the ratio of output to input power, of 36. The 6 ns output pulses were generated from the 2 m length ring using a silicon laser-driven semiconductor switch (LDSS). The quasi-optical ring resonator was designed with large waist sizes so that input pulses of up to 1 MW will stay under the 35 kV/cm electric field limit for ionization in ambient air. Maximum compression gain was achieved by matching the input coupling fraction to the round trip loss in the ring, achieving close to critical coupling. The experimental output pulse shape obtained after firing the LDSS was modeled using the reflectance, transmittance, and absorptance of the switch vs. time and vs. laser pulse fluence, with good agreement found with theory. The timing for the peak energy efficiency of 32% was found and the main loss mechanism limiting that efficiency was found to be the absorptance in the silicon wafer.

[Pathophysiology of sideroblastic anemia].

Sideroblastic anemias (SAs) are a diverse group of congenital and acquired disorders, characterized by anemia and the presence of ring sideroblasts in bone marrow. Congenital SA is a rare disorder that results from genetic mutations that impair heme biosynthesis, iron-sulfur [Fe-S] cluster biosynthesis, and mitochondrial protein synthesis. The predominant type of congenital SA is X-linked sideroblastic anemia, caused by mutations in the erythroid-specific δ-aminolevulinate synthase (ALAS2) gene, a key enzyme in the heme biosynthesis pathway in erythroid cells. SAs can also arise due to exposure to certain drugs or alcohol or to copper deficiency (secondary SAs). They are also often associated with myelodysplastic syndrome (idiopathic SA), and idiopathic SAs are the most frequently encountered type. This review discusses the current understanding of the pathophysiology underlying SA.

Prognostic insights after surgery for advances in understanding signet ring cell gastric cancer: a machine learning approach.

BACKGROUND: Signet ring cell (SRC) gastric carcinoma is traditionally associated with a poor prognosis. However, the literature has presented contradictory results. Linear models are the standard statistical tools typically used to study these conditions. However, machine learning (ML) models have the potential to replace or even outperform linear models in terms of predictive performance. METHODS: This study analyzed 608 patients diagnosed with gastric cancer at our institution. The analysis compared traditional linear models and ML models. Variables examined included demographic data, presence of an SRC component, lymph nodes (LNs) resected and affected (ratio), stage of the disease, body mass index, pathologic features, type of surgery, tumor location, and carcinoembryonic antigen levels to evaluate their influence on 5-year mortality and 2-year recurrence rates. RESULTS: SRC carcinoma was associated with poorer prognosis in terms of 5-year overall survival than non-SRC carcinoma. In addition, SRC exhibited higher rates of LN metastasis and a higher LN ratio (resected/affected) and was more prevalent in younger patients (<65 years). However, SRC was not an independent factor in the multivariate analysis. Linear models showed worse predictions for 5-year mortality and 2-year recurrence than ML models. The ML models did not consider the presence of the SRC component as an important variable. CONCLUSION: SRC gastric carcinoma continues to present an uncertain prognosis. ML models can evaluate prognosis more accurately than traditional linear models. Large-scale studies using ML algorithms are necessary to elucidate the predictive potential of such models.

NLRP12 inhibits PRRSV-2 replication by promoting GP2a degradation via MARCH8.

NLRP12, a member of the NLR family, has been shown to exert a vital function in orchestrating immune responses. Here, using the immunosuppressive porcine reproductive and respiratory syndrome virus (PRRSV) as a model, the role of NLRP12 in virus infection was deciphered. We demonstrated that overexpression of NLRP12 significantly restrained PRRSV replication, while NLRP12 silencing resulted in increased viral titer. Mechanistically, NLRP12 interacts with glycoprotein 2a (GP2a) through its LRR domain and recruits the membrane-associated RING-CH E3 ubiquitin ligase 8 (MARCH8) via the PYD domain. NLRP12 facilitates the lysine-48 (K48)-linked polyubiquitination of GP2a at K128 and induces its lysosome degradation via the MARCH8-NDP52 (nuclear dot protein 52 kDa) pathway. To counteract this, PRRSV Nsp2 effectively prevented the polyubiquitination of GP2a induced by NLRP12 by its deubiquitinating activity. Meanwhile, the overexpression of Nsp4 decreased the mRNA of endogenous NLRP12 and cleaved NLRP12 in a 3C-like protease activity-dependent manner, which collaboratively counteracts the antiviral function of NLRP12. Collectively, this study revealed the mechanisms of the NLRP12-MARCH8-NDP52 axis in the host defense against PRRSV, which might be harnessed for the development of anti-PRRSV therapies.

Filament formation activates protease and ring nuclease activities of CRISPR Lon-SAVED.

To combat phage infection, type III CRISPR-Cas systems utilize cyclic oligoadenylates (cAn) signaling to activate various auxiliary effectors, including the CRISPR-associated Lon-SAVED protease CalpL, which forms a tripartite effector system together with an anti-σ factor, CalpT, and an ECF-like σ factor, CalpS. Here, we report the characterization of the Candidatus Cloacimonas acidaminovorans CalpL-CalpT-CalpS. We demonstrate that cA4 binding triggers CalpL filament formation and activates it to cleave CalpT within the CalpT-CalpS dimer. This cleavage exposes the CalpT C-degron, which targets it for further degradation by cellular proteases. Consequently, CalpS is released to bind to RNA polymerase, causing growth arrest in E. coli. Furthermore, the CalpL-CalpT-CalpS system is regulated by the SAVED domain of CalpL, which is a ring nuclease that cleaves cA4 in a sequential three-step mechanism. These findings provide key mechanistic details for the activation, proteolytic events, and regulation of the signaling cascade in the type III CRISPR-Cas immunity.

Identification of the metabolites of nimbolide in rat by liquid chromatography combined with quadrupole/orbitrap mass spectrometry.

Nimbolide is a major furanoid compound isolated from Azadirachta indica. The aim of this study was to characterize the metabolites of nimbolide in rats and to propose the metabolic pathways. The metabolites were generated by incubating nimbolide (10 µM) with rat liver microsomes, nicotinamide adenine dinucleotide phosphate (NADPH), and nucleophiles (glutathione [GSH] or N-acetyl-lysine [NAL]) at 37°C for 60 min. For the in vivo study, nimbolide was intravenously administered to rats at a single dose of 10 mg/kg, and the bile and urine were collected. The metabolites were identified by ultra-high-performance liquid chromatography-quadrupole/orbitrap mass spectrometry (UPLC-Q/Orbitrap-MS) using electrospray ionization in positive ion mode. Totally, nine metabolites were detected, and their identities were characterized by accurate MS and MS/MS data. In GSH-supplemented liver microsomes, GSH conjugation was the primary elimination pathway. The furan ring was bioactivated into cis-butene-1,4-dial that can be trapped by GSH. In NAL-supplemented liver microsomes, two NAL conjugates (M4 and M5) derived from cis-butene-1,4-dial were observed. In rat bile and urine, N-acetyl-cysteine, cysteine-glycine, and GSH conjugate were also found. The current study provides an overview of the metabolism and the bioactivation profiles of nimbolide in rats, which aids in understanding its safety and activity.

Cation-π Interactions Based Conductive Hydrogels with Slide-Ring Structure Toward Super Long-Time in-air/Underwater Linear Sensing and Communication.

Conductive hydrogels (CHs) are attracted more attention in the flexible wearable sensors field, however, how to stably apply CHs underwater is still a big challenge. In order to achieve the usage of CHs in aquatic environments, the integrated properties such as water retention ability, resistance to swelling, toughness, adhesiveness, linear GF sensing, and long-term usage are necessary to consider, but rarely reported in the previous reports. This paper proposes CHs prepared using cationic and aromatic monomers along with polyrotaxanes-based crosslinkers. Due to the intermolecular cation-π interactions and topological slide-ring-based polyrotaxanes, the CHs exhibit good mechanical performance, adhesive nature, and anti-swelling properties. The presence of slide-ring-based topological architecture effectively mitigates stress concentration. Additionally, the encapsulation of PA allows CHs to maintain functionality even after 240 days of direct placement at room temperature. Notably, the designed CHs exhibit linear sensitivity in detecting land/underwater human motions, and serve as Morse code signal transmitters for information transmission. Thus, the designed CHs may have broad applications in the underwater wearable sensors field.

Dinuclear zinc(II) acetate complexes derived from N,N',S-tridentate Schiff bases: synthesis, structural study and Hirshfeld surface analysis.

Three dinuclear zinc(II) acetate complexes of the general formula [Zn{Ln}(AcO)]2, namely, di-µ-acetato-κ4O:O'-bis[({2-[(pyridin-2-ylmethylidene)amino]phenyl}sulfanido-κ3N,N',S)zinc(II)], [Zn2(C12H9N2S)2(C2H3O2)2] (n = 1), 4, µ-acetato-1:2κ2O:O'-acetato-2κO-[µ-(2-{[1-(pyridin-2-yl)ethylidene]amino}phenyl)sulfanido-1κS:2κ3N,N',S][(2-{[1-(pyridin-2-yl)ethylidene]amino}phenyl)sulfanido-1κ3N,N',S]dizinc(II), [Zn2(C13H11N2S)2(C2H3O2)2] (n = 2), 5, and µ-acetato-1:2κ2O:O'-acetato-2κO-[µ-(2-{[phenyl(pyridin-2-yl)methylidene]amino}phenyl)sulfanido-1κS:2κ3N,N',S][(2-{[phenyl(pyridin-2-yl)methylidene]amino}phenyl)sulfanido-1κ3N,N',S]dizinc(II)-bis(2-aminophenyl) disulfide (2/1), [Zn2(C18H13N2S)2(C2H3O2)2]·0.5C12H12N2S2 (n = 3), 6·0.5(2-APS)2, were obtained from the reaction of 2-R-(pyridin-2-yl)benzothiazoline precursors (R = H, 1; R = Me, 2; R = Ph, 3) with zinc acetate dihydrate in a 1:1 ratio. All the complexes crystallized as dinuclear species and complex 6 cocrystallized with one molecule of bis(2-aminophenyl) disulfide (2-APS)2. The anionic Schiff base ligands {Ln}- displayed a κ2N,κS-tridentate coordination mode with the formation of two five-membered chelate rings. In 4, 5 and 6·0.5(2-APS)2, both ZnII ions are pentacoordinated and the coordination sphere of 4 was different with respect to those in 5 and 6·0.5(2-APS)2. For 4, the X-ray diffraction study showed a dinuclear complex containing two bridging acetate ligands linked to both ZnII ions. For 5 and 6·0.5(2-APS)2, the dinuclear complexes displayed one bridging acetate ligand linked to both ZnII ions, where the first ZnII ion includes a dative bond with one S atom from an adjacent anionic Schiff base {Ln}-, while the second ZnII ion is coordinated to one terminal acetate ligand. In each dinuclear complex, the geometry is the same for both ZnII metal centres. The local geometry of the ZnII cation in 4 is halfway between trigonal bipyramidal and square pyramidal local geometries; in 5 and 6, the local geometries are described as distorted square pyramidal. Hirshfeld surface analysis of 5 and 6 showed the predominance of H...H interactions, as well as the contribution of C-H...C, C-H...O and C-H...S noncovalent interactions to the cohesion of the crystalline network of the ZnII complexes.

Profiling Cullin4-E3 ligases interactomes and their rewiring in influenza A virus infection.

Understanding the integrated regulation of cellular processes during viral infection is crucial for developing host-targeted approaches. We have previously reported that an optimal in vitro infection by influenza A (IAV) requires three components of Cullin 4-RING E3 ubiquitin ligases (CRL4) complexes, namely the DDB1 adaptor and two Substrate Recognition Factors (SRF), DCAF11 and DCAF12L1, which mediate non-degradative poly-ubiquitination of the PB2 subunit of the viral polymerase. However, the impact of IAV infection on the CRL4 interactome remains elusive. Here, using Affinity Purification coupled with Mass Spectrometry (AP-MS) approaches, we identified cellular proteins interacting with these CRL4 components in IAV-infected and non-infected contexts. IAV infection induces significant modulations in protein interactions, resulting in a global loss of DDB1 and DCAF11 interactions, and an increase in DCAF12L1-associated proteins. The distinct rewiring of CRL4's associations upon infection impacted cellular proteins involved in protein folding, ubiquitination, translation, splicing, and stress responses. Using a split-nanoluciferase-based assay, we identified direct partners of CRL4 components and via siRNA-mediated silencing validated their role in IAV infection, representing potential substrates or regulators of CRL4 complexes. Our findings unravel the dynamic remodeling of the proteomic landscape of CRL4's E3 ubiquitin ligases during IAV infection, likely involved in shaping a cellular environment conducive to viral replication and offer potential for the exploration of future host-targeted antiviral therapeutic strategies.

Comparison of the AO/OTA 1996/2007 and 2018 pelvic ring fracture classifications.

Pelvic ring fractures may present with relevant mechanical and haemodynamic instability. Classifications of the bony or ligamentous injuries of the pelvic ring are well established. The most common classifications used analyse the injury mechanisms and the resulting instability of the pelvic ring structure. Fracture classifications should be simple and easy to use, comprehensive, and radiographically and anatomically based, resulting in a hierarchical alphanumeric order of types and subtypes and thereby allow adequate treatment decisions based on a high degree of inter- and intraobserver reliability. In 2018 a new AO/OTA pelvic ring fracture and dislocation classification was published that combined the most commonly used "historical" classification schemes, e.g. the Tile/AO classification and the classification according to Young and Burgess. Compared with these older classifications, several relevant changes were integrated in the 2018 edition. The changes between the AO/OTA 1996/2007 and 2018 classifications were analysed in detail. Overall, several problems were identified regarding the type-B pelvic ring injury classification. These changes may result in difficulties in classifying pelvic ring injuries and thereby prevent relevant comparisons between former and future clinical studies on pelvic injuries.Level of Evidence: V.

Aberrant right subclavian artery intervention can provide relief of dysphagia.

BACKGROUND: An aberrant right subclavian artery represents the most common aortic arch vascular anomaly. Conventional wisdom states that these anomalies do not result in dysphagia, but rather serve as "red herrings". Clearly, in the vast majority of cases, this holds true. Nonetheless, one should never say never. METHODS: Herein, we present a cohort of four children with debilitating dysphagia resulting from an aberrant right subclavian artery. Subclavian reimplantation via a right posterolateral thoracotomy was performed successfully in all cases. RESULTS: Dysphagia resolved postoperatively, and all patients were able to advance to a normal diet. They were able to gain appropriate weight postoperatively and continue to do well at most recent clinical follow-up. CONCLUSIONS: This case series suggests that aberrant right subclavian artery anatomy should be considered a potential aetiology of dysphagia, albeit rarely. Surgical intervention for select patients can provide dramatic resolution of symptoms.

The novel balloon-expandable Myval transcatheter heart valve: systematic review of aortic, mitral, tricuspid and pulmonary indications.

INTRODUCTION AND OBJECTIVES: Myval technology represents the first balloon-expandable alternative since the Edwards system became commercially available. Despite certain controversies, its use has rapidly expanded. We aimed to gather all the available literature regarding its indications and outcomes. METHODS: A comprehensive search of articles published between December 2016 and May 2024 was conducted using BioMedCentral, Google Scholar, and PubMed to evaluate the main outcomes of Myval for native aortic stenosis (AS) (meta-analysis) and off-label uses (systematic review). RESULTS: A total of 151 studies were identified, and 74 were included in the analysis, covering aortic (n = 51), mitral (n = 9), tricuspid (n = 6), and pulmonary (n = 8) valve positions. A meta-analysis of studies on native AS demonstrated that Myval is safe and effective, with a 30-day mortality rate of 1.3%, good hemodynamic performance, low rates of pacemaker implantation (8.8%), and ≥ moderate paravalvular regurgitation (1.3%). Compared with other contemporary devices, Myval was competitive and associated with lower rates of pacemaker implantation. In a systematic review of off-label indications, Myval was also found to be safe and effective. In bicuspid AS, pure regurgitation, and aortic valve-in-valve procedures, success rates were 100%, 92%, and 100%, respectively, with pacemaker rates of 9.9%, 22.2%, and 3%, respectively. For mitral valve-in-valve/in-ring procedures, the success rate was 96.9%, while in tricuspid and pulmonary positions, small case series reported 100% success rates for both, with minimal procedural complications. CONCLUSIONS: Myval technology is safe and effective for the treatment of native valvular disease and dysfunctional prostheses or rings in all heart valve positions, although larger scale studies are warranted.

Cytokinetic contractile ring structural progression in an early embryo: positioning of scaffolding proteins, recruitment of α-actinin, and effects of myosin II inhibition.

Our knowledge of the assembly and dynamics of the cytokinetic contractile ring (CR) in animal cells remains incomplete. We have previously used super-resolution light microscopy and platinum replica electron microscopy to elucidate the ultrastructural organization of the CR in first division sea urchin embryos. To date, our studies indicate that the CR initiates as an equatorial band of clusters containing myosin II, actin, septin and anillin, which then congress over time into patches which coalesce into a linear array characteristic of mature CRs. In the present study, we applied super-resolution interferometric photoactivated localization microscopy to confirm the existence of septin filament-like structures in the developing CR, demonstrate the close associations between septin2, anillin, and myosin II in the CR, as well as to show that septin2 appears consistently submembranous, whereas anillin is more widely distributed in the early CR. We also provide evidence that the major actin cross-linking protein α-actinin only associates with the linearized, late-stage CR and not with the early CR clusters, providing further support to the idea that α-actinin associates with actomyosin structures under tension and can serve as a counterbalance. In addition, we show that inhibition of actomyosin contraction does not stop the assembly of the early CR clusters but does arrest the progression of these structures to the aligned arrays required for functional cytokinesis. Taken together our results reinforce and extend our model for a cluster to patch to linear structural progression of the CR in sea urchin embryos and highlight the evolutionary relationships with cytokinesis in fission yeast.