Implantation Strategy Research Articles

Insights from Computational Fluid Dynamics and In Vitro Studies for Stent Protrusion in Iliac Vein: How Far Shall We Go?

These findings provide significant implications for the enhancement of iliac vein stent implantation strategies and stent design. The prevalent use of stents for treating Iliac Vein Compression Syndrome (IVCS) has shown efficacy, yet the associated clinical adverse events, including stent restenosis and postoperative thrombosis, are significant concerns. Up to now, the mechanism how the stent implantation induces the restenosis and DVT is still unclear. Our study hypothesizes that these adverse outcomes arise from altered blood flow dynamics following stent implantation. Employing computational modeling and medical imaging, we simulated IVCS after various stenting procedures to assess their impact on venous blood flow characteristics, including wall shear stress (WSS), residence time (RRT), and oscillatory shear index (OSI). Our findings reveal that a stent protruding into the vena cava impedes blood circulation, with increased protrusion exacerbating this obstruction. This is particularly evident at the vein bifurcation, where low WSS and elevated OSI and RRT are observed. Moreover, a higher stent strut density further obstructs blood flow, deteriorating the hemodynamic environment. Consequently, stent protrusion into the vena cava can enhance the likelihood of adverse post-surgical events. These insights have profound implications for optimizing iliac vein stent implantation techniques and stent design.

Numerical simulation of individualized flow diversion cerebral aneurysms treatment

AbstractFlow diverter implantation has emerged as a highly effective treatment for cerebral aneurysms. However, the variability in patient‐specific vascular anatomy necessitates detailed pre‐operative planning to mitigate potential complications arising from standard, one‐size‐fits‐all devices. To address these challenges, robust predictive simulation tools are essential for optimizing flow diverter design and implantation strategies tailored to the unique characteristics of each patient's anatomy. This study focuses on developing an advanced numerical simulation tool for modeling the mechanical behavior of braided flow diverters during crimping and navigation through patient‐specific vasculature. Using isogeometric analysis (IGA) with NURBS‐based representations in LS‐Dyna, the intricate deformations of the flow diverter wires during catheter crimping are captured with high accuracy. The patient‐specific vessel geometries, derived from imaging data, are integrated into the model to account for variations in vascular structure, ensuring precise alignment and controlled navigation of the device. The navigation process relies on optimizing the central axis of the blood vessel to minimize torsional stress on the flow diverter, reducing the risk of device malfunction or failure during deployment. By incorporating patient‐specific information, such as vessel curvature and tortuosity, the simulation tool enables the prediction of potential issues, thus allowing for intervention planning that is tailored to individual anatomy. This patient‐specific approach enhances the safety and efficacy of flow diverter implantation and serves as a foundation for improved device design prior to prototype development.

Five-year clinical outcomes of STEMI patients treated with a pre-specified bioresorbable vascular scaffold implantation technique: Final results of the BVS STEMI STRATEGY-IT

BackgroundData on Absorb bioresorbable vascular scaffold (BVS) use in patients presenting with ST-segment elevation myocardial infarction (STEMI) are limited. Furthermore, Absorb studies including STEMI patients lacked a prespecified implantation technique to optimize BVS deployment. This study examines the 5-year outcomes of BVS in STEMI patients using an optimized implantation strategy and the impact of prolonged dual antiplatelet therapy (DAPT). MethodsThe BVS STEMI STRATEGY-IT study is a prospective, non-randomized, single-arm multicenter trial (NCT02601781). It involved 505 STEMI patients undergoing primary percutaneous coronary intervention with a predefined BVS implantation protocol. Key endpoints were a 5-year device-oriented composite endpoint (DOCE) of cardiac death, target-vessel myocardial infarction (TV-MI), and ischemia-driven target lesion revascularization (ID-TLR). The study also compared outcomes based on DAPT duration (36 months vs. shorter). Results502 (99.4 %) patients completed the 5-year follow-up. DOCE rate was 2.4 %. ID-TLR, TV-MI, and cardiac death rates were 1.6 %, 0.8 %, and 0.6 %, respectively. No DOCE occurred between three and five years. Scaffold thrombosis (ScT) was 1 %, all occurring within 24 months. Longer-term DAPT significantly reduced DOCE (1.3 % vs. 4.3 %; HR: 0.29; 95 % CI: 0.1–0.9; p = 0.03) driven by a lower rate of TV-MI (0 % vs. 2.2 %; p = 0.018) compared to shorter-term DAPT, as well as ScT (0 % vs 2.7 %, p = 0.007). ConclusionsThis study shows favorable 5-year outcomes for BVS in selected STEMI patients with an optimized implantation strategy. Prolonged DAPT further improved outcomes, emphasizing its role in reducing adverse events during scaffold resorption. Further research is needed to assess newer-generation bioresorbable devices.

Mo Migration‐Induced Crystalline to Amorphous Conversion and Formation of RuMo/NiMoO4 Heterogeneous Nanoarray for Hydrazine‐Assisted Water Splitting at Large Current Density

AbstractManipulating the atomic structure of the catalyst and tailoring the dissociative water‐hydrogen bonding network at the catalyst‐electrolyte interface is essential for propelling alkaline hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR), but remains a great challenge. Herein, we constructed an advanced a‐RuMo/NiMoO4/NF heterogeneous electrocatalyst with amorphous RuMo alloy nanoclusters anchored to amorphous NiMoO4 skeletons on Ni foam by a heteroatom implantation strategy. Theoretical calculations and in situ Raman tests show that the amorphous and alloying structure of a‐RuMo/NiMoO4/NF not only induces the directional evolution of interfacial H2O, but also lowers the d‐band center (from −0.43 to −2.22 eV) of a‐RuMo/NiMoO4/NF, the Gibbs free energy of hydrogen adsorption (ΔGH*, from −1.29 to −0.06 eV), and the energy barrier of HzOR (ΔGN2(g)=1.50 eV to ΔGN2*=0.47 eV). Profiting from these favorable factors, the a‐RuMo/NiMoO4/NF exhibits excellent electrocatalytic performances, especially at large current densities, with an overpotential of 13 and 129 mV to reach 10 and 1000 mA cm−2 for HER. While for HzOR, it needs only −91 and 276 mV to deliver 10 and 500 mA cm−2, respectively. Further, the constructed a‐RuMo/NiMoO4/NF||a‐RuMo/NiMoO4/NF electrolyzer demands only 7 and 420 mV to afford 10 and 500 mA cm−2.

Mo Migration-Induced Crystalline to Amorphous Conversion and Formation of RuMo/NiMoO4 Heterogeneous Nanoarray for Hydrazine-Assisted Water Splitting at Large Current Density.

Manipulating the atomic structure of the catalyst and tailoring the dissociative water-hydrogen bonding network at the catalyst-electrolyte interface is essential for propelling alkaline hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR), but remains a great challenge. Herein, we constructed an advanced a-RuMo/NiMoO4/NF heterogeneous electrocatalyst with amorphous RuMo alloy nanoclusters anchored to amorphous NiMoO4 skeletons on Ni foam by a heteroatom implantation strategy. Theoretical calculations and in situ Raman tests show that the amorphous and alloying structure of a-RuMo/NiMoO4/NF not only induces the directional evolution of interfacial H2O, but also lowers the d-band center (from -0.43 to -2.22 eV) of a-RuMo/NiMoO4/NF, the Gibbs free energy of hydrogen adsorption (ΔGH*, from -1.29 to -0.06 eV), and the energy barrier of HzOR (ΔGN2(g)=1.50 eV to ΔGN2*=0.47 eV). Profiting from these favorable factors, the a-RuMo/NiMoO4/NF exhibits excellent electrocatalytic performances, especially at large current densities, with an overpotential of 13 and 129 mV to reach 10 and 1000 mA cm-2 for HER. While for HzOR, it needs only -91 and 276 mV to deliver 10 and 500 mA cm-2, respectively. Further, the constructed a-RuMo/NiMoO4/NF||a-RuMo/NiMoO4/NF electrolyzer demands only 7 and 420 mV to afford 10 and 500 mA cm-2.

The Suboptimal QLV Ratio May Indicate the Need for a Left Bundle Branch Area Pacing-Optimized Cardiac Resynchronization Therapy Upgrade.

Background: The QLV ratio (QLV/baseline QRS width) is an established intraoperative-measurable parameter during cardiac resynchronization therapy (CRT) device implantation, potentially predicting the efficacy of electrical resynchronization. Methods: Left bundle branch area pacing-optimized CRT (LOT-CRT) is a novel approach with the potential to improve both responder rate and responder level in the CRT candidate patient group, even when an optimal electro-anatomical left ventricular lead position is not achievable. In our observational study, 72 CRT-defibrillator candidate patients with a QRS duration of 160 ± 12 ms were consecutively implanted. Using a QLV-ratio-based implant strategy, 40 patients received a biventricular CRT device (Biv-CRT) with an optimal QLV ratio (≥70%). Twenty-eight patients with a suboptimal QLV ratio (<70%) were upgraded intraoperatively to a LOT-CRT system. Patients were followed for 12 months. Results: The postoperative results showed a significantly greater reduction in QRS width in the LOT-CRT patient group compared to the Biv-CRT patients (40.4 ± 14 ms vs. 32 ± 13 ms; p = 0.024). At 12 months, the LOT-CRT group also demonstrated a significantly greater improvement in left ventricular ejection fraction (14.9 ± 8% vs. 10.3 ± 7.4%; p = 0.001), and New York Heart Association functional class (1.2 ± 0.5 vs. 0.8 ± 0.4; p = 0.031), and a significant decrease in NT-pro-BNP levels (1863± 380 pg/mL vs. 1238 ± 412 pg/mL; p = 0.012). Notably, the LOT-CRT patients showed results comparable to Biv-CRT patients with a super-optimal QLV ratio (>80%) in terms of QRS width reduction and LVEF improvement. Conclusions: Our single-center study demonstrated the feasibility of a QLV-ratio-based implantation strategy during CRT implantation. Patients with a LOT-CRT system showed significant improvements, whereas Biv-CRT patients with a super-optimal QLV ratio may not be expected to benefit from an additional LOT-CRT upgrade.

Marmoset and human trophoblast stem cells differ in signaling requirements and recapitulate divergent modes of trophoblast invasion

Early human trophoblast development has remained elusive due to the inaccessibility of the early conceptus. Non-human primate models recapitulate many features of human development and allow access to early postimplantation stages. Here, we tracked the pre- to postimplantation transition of the trophoblast lineage in superficially implanting marmoset embryos invivo. We differentiated marmoset naive pluripotent stem cells into trophoblast stem cells (TSCs), which exhibited trophoblast-specific transcriptome, methylome, differentiation potential, and long-term self-renewal. Notably, human TSC culture conditions failed to support marmoset TSC derivation, instead inducing an extraembryonic mesoderm-like fate in marmoset cells. We show that combined MEK, TGF-β/NODAL, and histone deacetylase inhibition stabilizes a periimplantation trophoblast-like identity in marmoset TSCs. By contrast, these conditions differentiated human TSCs toward extravillous trophoblasts. Our work presents a paradigm to harness the evolutionary divergence in implantation strategies to elucidate human trophoblast development and invasion.

Influence of implantation strategy in the transition from temporary left ventricular assist device to durable mechanical circulatory support.

Bridging from temporary microaxial left ventricular assist device (tLVAD) to durable left ventricular assist device (dLVAD) is playing an increasing role in the treatment of terminally ill heart failure patients. Scant data exits about the best implantation strategy. The aim of this study is to analyze differences in dLVAD implantation technique and effects on patient outcomes. Data from 341 patients (19 European centers), between 01/2017 and 10/2022, who underwent bridge to bridge implantation from tLVAD to dLVAD were retrospectively analyzed. The outcomes of the different implantation techniques on cardiopulmonary bypass (CPB), extracorporeal life support (ECLS) or tLVAD were compared. Durable LVAD implantation was performed employing CPB in 70% of cases (n = 238, group 1), ECLS in 11% (n = 38, group 2) and tLVAD in 19% (n = 65, group 3).Baseline characteristics showed no significant differences in age (p = 0.140), BMI (p = 0.388), creatinine (p = 0.659), Meld score (p = 0.190) and rate of dialysis (p = 0.110). Group 3 had significantly less patients with preoperatively invasive ventilation and cardiopulmonary resuscitation before tLVAD implantation (p = 0.009 and p < 0.001 respectively). Concomitant procedures were performed more often in group 1 and 2 compared to group 3 (24%, 37% and 5%, respectively, p < 0.001).The 30-day mortality showed a significant better survival after inverse probability of treatment weighting in group 3, but the 1-year mortality showed no significant differences between groups (p = 0.012 and 0.581, respectively).Post-operative complications like rate of RVAD implantation or re-thoracotomy due to bleeding, post-operative respiratory failure and renal replacement therapy showed no significant differences between groups.Freedom from first adverse event like stroke, driveline infection or pump thrombosis during follow-up was not significantly different between groups.Post-operative blood transfusion within 24-hours were significantly higher in groups 1 and 2 compared to surgery on tLVAD support (p < 0.001 and p = 0.003, respectively). In our analysis, the transition from tLVAD to dLVAD without further circulatory support did not show a difference in post-operative long-term survival, but a better 30-day survival was reported. The implantation by using only tLVAD showed a reduction in post-operative transfusion rates, right heart failure and the re-thoracotomy rate without increasing the risk of postoperative stroke or pump thrombosis. In this small cohort study, our data supports the hypothesis that we could demonstrate dLVAD implantation on tLVAD is a safe and feasible technique in selected patients.

Elucidating the hemodynamic impact of residual stenosis post-carotid artery stenting: A numerical study.

Residual stenosis (RS) and hemodynamics demonstrate a significant correlation with postoperative in-stent restenosis/thrombosis following carotid artery stenting (CAS). This study endeavors to elucidate the potential associations between RS and adverse postoperative hemodynamic factors. This study utilized 46 patient-specific carotid artery models post-stenting, which were categorized into two groups based on the presence of RS: the normal group (N, n=23) and the RS group (RS, n=23). A comparative analysis was conducted to evaluate the discrepancies in geometry and adverse hemodynamic parameters, alongside investigating the potential correlation between hemodynamic and geometric parameters. The results reveal that a higher reflux flow volume is discernible in the RS group during low-velocity phases of the cardiac cycle, concomitant with an augmented extent of areas exposed to oscillatory shear stress and extended particle residence time. Moreover, the adverse hemodynamic parameters exhibit a positive correlation with the degree of stent expansion, stent length in the common carotid artery (CCA), and the distal slope of the RS. The distal slope and tortuosity of RS significantly influence the development of adverse hemodynamic conditions post-stenting, exacerbating the hemodynamic environment near the stenosis. Interestingly, while an extended stent length in the internal carotid artery (ICA) region improves hemodynamics by reducing flow disturbance, a longer stent in the CCA significantly worsens these conditions. Hence, it is prudent to analyze the characteristics of the local lesion regions to optimize the strategy for stent implantation.

Biomechanical Effects of Titanium Alloy Based Single versus Dual Cage Fusion Devices

Degenerative disc disease is an increasing problematic complication following lumbar fusion surgeries. Posterior lumbar interbody fusion (PLIF) is a well-established surgical method for spine stability following intervertebral disc removal. The position and number of titanium cages in PLIF are remain contingent on individual surgeon experience. Thus, a systemic investigation of the efficacy of titanium single mega cage versus two cages in treating degenerative lumbar spinal diseases is imperative. A biomechanical study was aimed to compare the stability achieved in PLIF through interbody reconstruction using a single mega cage (32 mm) Vs. a dual cage (22 mm). Normal intact finite element model of L3–L4 was developed based on computed tomography images from a healthy 27-year-old male volunteer. The study tested the intact model (Model A) and its surgically operated counterparts using four PLIF implantation methods: single transverse cage (Model B), single transverse cage with bone graft (Model C), dual transverse cage (Model D), and dual transverse cage with bone graft (Model E). Combined loads simulating physiological motions—flexion, extension, axial rotation, and lateral bending —were applied across all loading directions. The assessment includes all model range of motion (ROM), micromotion between the cage and endplate, and stress on the cage and internal fixation system (screw and rod). The ROM between Models B, C, D and E were consistently reduced by over 71% compared to intact Model A under all motion scenarios. Model D exhibited the highest peak stress of 115 MPa on the cage during flexion, surpassing Model C and E (Flexion) by fourfold. Model E demonstrated the lowest cage stress (20 MPa) during extension, outperforming the other models. Notably, Model E exhibited minimal endplate stress (2 MPa), cage stress (21 MPa), micromotion (13 µm) during extension, and screw-rod stress (56 MPa) during flexion, making it superior to other implantation methods. In the context of PLIF, Model E showed enhanced biomechanical stability, reducing ROM, stress on the endplates, cage, screw-rod system and micromotion. Alternatively, Model C may be a viable alternative in standard PLIF, especially in cases with limited intervertebral space, providing efficient clinical outcomes with shorter operative times and reduced costs and ease of implantation. Also, this computational study provides valuable understandings into optimizing cage implantation strategies for improved outcomes during PLIF.

Delayed Intervention’s Impact on Transcatheter Mitral Valve Implantation Strategy

Delayed Intervention’s Impact on Transcatheter Mitral Valve Implantation Strategy

Surgical Strategies for Renal Transplantation: A Pictorial Essay.

This pictorial essay aims to navigate through the complexities and challenges of renal transplantation (RT), by weaving together visual imagery with clinical insights within a comprehensive illustrative surgical guide. Herein, we provide a detailed visual exploration of the intricate anatomy and surgical processes necessary for both renal graft retrieval from the donor and also for an adequate implantation in the recipient. Regarding graft retrieval, after reviewing the relevant retroperitoneal surgical anatomy, and donor nephrectomy techniques, graft preservation and optimal backbench graft dissection principles were meticulously analyzed. Thereafter, the recipient surgical strategy for graft implantation was addressed, focusing on preoperative preparations, the site of implantation selection, exposure, operative bed dissection, graft revascularization, and urinary tract reconstruction. Careful donor and recipient selection, meticulous surgical execution, and rigorous postoperative management clearly hold a pivotal role in optimizing patient outcomes. Fostering a deeper understanding of the surgical nuances and clinical management practices that contribute to successful results post-RT, we hope to provide a useful practical tool for clinicians about to embark on the treacherous road of RT surgery. Innovative technologies and surgical practices that have already significantly improved the safety and effectiveness of RT stand testament to the importance of further scientific inquiry, conceptual developments, and clinical integration. Moving forward, it is essential that the medical community continues to refine these strategies and advocate for equitable access to transplantation, ensuring that advancements in the field translate into real-world benefits for all patients grappling with ESRD. The collaborative efforts of multidisciplinary teams are essential in addressing the complex clinical challenges associated with RT, with the ultimate goal of improving patient survival, enhancing graft longevity, and reducing healthcare disparities.

Three-Year Left Ventricular Assist Device Outcomes and Strategy After Heart Transplant Allocation Score Change

BackgroundThe United Network for Organ Sharing (UNOS) adopted new criteria for the heart allocation score on 10/18/2018 to reflect changing trends of candidates’ mortality while awaiting transplant. We examined the impact of these policy changes on rates of left ventricular assist device (LVAD) implantation and outcomes posttransplant from a relatively newer UNOS database. MethodsThe UNOS registry was used to identify first-time adult heart recipients with LVAD at listing or transplant who underwent transplantation between 1/1/2016 and 3/10/2020. Survival data was collected through 3/30/2023. Those listed prior to 10/18/2018 but transplanted after were excluded. Patients were divided into before or after change groups. Demographics and clinical parameters were compared. Survival was analyzed with Kaplan-Meier curves and log-rank tests. A p<0.05 was considered significant. ResultsWe identified 4387 heart recipients with LVAD in the before (n=3606) and after (n=781) score change eras. The after group had a lower rate of LVAD implantation while listed compared to the before group (20.4% vs 34.9%, p<0.0001), and were more likely to be female (25.1% vs 20.2%, p=0.002); in both groups, most recipients (62.8%) were white. There was significantly farther distance from the donor hospital to transplant center in the after group (264.4 NM vs 144.2NM, p<0.0001) and decreased waitlist days (84.9 ± 105.1 vs 369.2 ± 459.5, p<0.0001). Recipients in the after group were more likely to utilize ECMO (3.7% vs 0.5%, p<0.0001) and IV inotropes (19.1% vs 7.5%, p<0.0001), and receive a CDC increased-risk donor organ (37.9% vs 30.5%, p<0.0001). Survival at 3-years was comparable between the two groups. ConclusionsThe allocation score change in 2018 yielded considerable changes in mechanical circulatory support device implantation strategy and outcomes. The rate of LVAD implantation decreased with increased utilization of temporary mechanical circulatory support devices.

A Speech Neuroprosthesis in the Frontal Lobe and Hippocampus: Decoding High-Frequency Activity into Phonemes.

Loss of speech due to injury or disease is devastating. Here, we report a novel speech neuroprosthesis that artificially articulates building blocks of speech based on high-frequency activity in brain areas never harnessed for a neuroprosthesis before: anterior cingulate and orbitofrontal cortices, and hippocampus. A 37-year-old male neurosurgical epilepsy patient with intact speech, implanted with depth electrodes for clinical reasons only, silently controlled the neuroprosthesis almost immediately and in a natural way to voluntarily produce 2 vowel sounds. During the first set of trials, the participant made the neuroprosthesis produce the different vowel sounds artificially with 85% accuracy. In the following trials, performance improved consistently, which may be attributed to neuroplasticity. We show that a neuroprosthesis trained on overt speech data may be controlled silently. This may open the way for a novel strategy of neuroprosthesis implantation at earlier disease stages (eg, amyotrophic lateral sclerosis), while speech is intact, for improved training that still allows silent control at later stages. The results demonstrate clinical feasibility of direct decoding of high-frequency activity that includes spiking activity in the aforementioned areas for silent production of phonemes that may serve as a part of a neuroprosthesis for replacing lost speech control pathways.

Pressure-driven molecule implantation enabling ultrahigh-rate and ultralong-life zinc ion batteries

Durable cathode materials with high specific capacity are essential for aqueous zinc ion batteries (AZIBs). However, vanadium-based materials endure irreversible structural collapse, sluggish diffusion kinetics, and low working voltage. In this study, we propose a unique pressure-driven molecule implantation (PMI) strategy to fabricate a laminar organic–inorganic hybrid cathode (PMI-VO) for AZIBs by coupling polyaniline (PANI) with vanadium oxide. The bipolar protonation of implanted electroactive PANI provides abundant active sites for ion/electron transfer and Zn2+/H+ storage in PMI-VO. Importantly, the formed C-V-O interfacial coupling bonds in the cycling process effectively relieve the intercalation stress and strengthen the redox kinetics and structural integrity of V2O5. In situ infrared spectroscopy and theoretical calculations reveal the PMI-induced multiple ions storage mechanisms in the PMI-VO cathode. Accordingly, PMI-VO cathode performs a superior specific capacity of 522 mAh∙g−1 at 0.2 A∙g−1, a high operating voltage of 0.86 V, a high energy density (387.4 Wh∙kg−1), and splendid long-life stability (over 15,000 cycles at 20 A∙g−1 with 191 mAh∙g−1). Therefore, this pressure-driven molecule implantation strategy provides a pioneering method to fabricate superior cathode materials of advanced AZIBs.

Electrothermal-assisted all-weather solar steam generator based on hydrogel implantation strategy

Using solar energy to treat sewage is a feasible scheme to alleviate the shortage of water resources and reduce carbon emissions. However, the fluctuation of sunlight intensity poses a great challenge to the stability of the treatment process, which hinders its application in the actual water treatment scene. Herein, based on the adhesion of hydrogel, an electrothermal-assisted all-weather solar steam generator with sandwich structure was synthesized through hydrogel implantation strategy, in which polyacrylamide hydrogel with thermal grease-modified heating wires was implanted as the middle heat conduction layer, the photothermal evaporation layer as the upper layer and the waste heat evaporation layer as the bottom layer. The electrothermal assisted solar evaporator (EASE) perfectly achieves the superposition of photothermal and electrothermal effects, and can achieve high interfacial water evaporation performance under extremely low auxiliary working voltage. Applying a low voltage of 2 V to both ends of the evaporator can achieve a high evaporation rate of 4.58 kg m−2h−1 under 1 solar irradiation, which is similar to the sum of the evaporation rate under only 1 solar illumination (2.22 kg m−2h−1) and a 2 V voltage input (2.26 kg m−2h−1). More interestingly, the suitable thickness of the hydrogel layer not only ensures the transfer of heat between layers, but also weakens the heat loss caused by the water flow effect. The implantation strategy ensures the stability of the water structure and inhibits the hydrogen reaction of electrolytic water in the electrothermal process. This work provides an important theoretical and practical reference for the preparation of all-weather solar interface water purification equipment.

Constructing surface protective film of V-Se-O to promote zinc ion storage by surface oxygen implantation strategy

Interfacial chemical modification is an effective strategy to adjust the strong Coulombic ion-lattice interactions with high valence cations experienced by electrode materials, facilitating the reaction kinetic. In this paper, a simple and fast surface oxygen implantation strategy was designed to adjust the electronic structure of stainless steel (SS) supported vanadium diselenide (VSe2) nanosheets and form a surface protective film, which effectively accelerates the reaction kinetics of Zn2+ and extends the cycle life of the battery. It is demonstrated that the conductivity, pseudocapacitance and specific capacity can be tuned by selectively introducing oxygen species to the surface, which provides an important reference for the design of electrodes with controlled surface chemistry. Density functional theory (DFT) calculations also confirm that the electronic structure can be adjusted by surface oxygen injection strategy, which not only improves the conductivity, but also adjusts the adsorption energy, thus providing favorable conditions for zinc ion storage. Benefiting from the selenium vacancies and pores generated by the removal of part of selenium, and the oxide film formed on the surfaces, the VSe2-xOx-SS-30 electrode showed higher specific capacity (188.4 mAh/g at 0.5 A g−1 after 50 cycles), better rate performance (107.1 mAh/g at 4 A g−1) and more satisfactory cycling stability (83.1 mAh/g at 5 A g−1 after 1800 cycles) than VSe2-SS electrode. Importantly, the flexible quasi-solid-state VSe2-xOx-SS-30//Zn battery also exhibits high specific capacity and excellent environmental adaptability. Furthermore, the zinc (de)intercalation and transformation reactions mechanism was revealed by some ex-situ/in-situ techniques.

Vestibular Impairment and Postural Development in Children With Bilateral Profound Hearing Loss

Children with profound hearing loss (HL) and vestibular impairment have worse cochlear implant outcomes compared with those without vestibular impairment. However, the decision for cochlear implantation is rarely based on vestibular function assessment as a complement to audiologic testing. To identify the prevalence of vestibular impairment according to HL origin and to assess the association between vestibular impairment and delayed posturomotor development in children with profound HL. This cohort study was conducted in a pediatric referral center for cochlear implantation in Paris, France, using medical records data on HL origin, vestibular assessment, and ages of developmental milestone achievement. The cohort included children with profound HL (loss >90 dB HL) who completed vestibular assessment prior to cochlear implantation between January 1, 2009, and December 31, 2019. Data analyses were conducted between January and June 2023. The primary outcome was prevalence of vestibular impairment according to HL origin. Children were classified into 3 groups according to their responses to vestibular testing: normal vestibular function (NVF), partially impaired vestibular function (PVF), and complete bilateral vestibular loss (CBVL). Generalized logit models were performed to evaluate the association between vestibular impairment and causes of HL as well as posturomotor development delay. A total of 592 children were included (308 males [52.0%]; mean [SD] age, 38 [34] months). In children with documented HL origin (n = 266), 45.1% (120) had HL with genetic origin, 50.0% of which were syndromic (mainly Usher and Waardenburg syndromes) and 50.0% were nonsyndromic (mainly associated with connexin 26). Among patients with infectious HL origin (n = 74), 70.3% (52) had cytomegalovirus (CMV) infection. Vestibular impairment was found in 44.4% (263 of 592) of the children; it was mostly symmetrical in 88.9% (526) and was CBVL in 5.7% (34) of the cases. Vestibular impairment was present in 78.3% (47) of children with genetic syndromic HL (56.7% [34] with PVF; 21.7% [13] with CBVL) and in 69.2% (36) of children with CMV infection (57.7% [30] with PVF; 11.5% [6] with CBVL). Genetic syndromic HL origin was found to be more often associated with both PVF and CBVL than other HL causes. The odds of having delays in 4 developmental milestones (head holding, sitting, standing with support, and independent walking) were higher in both PVF and CBVL (eg, head-holding odds ratios: 2.55 and 4.79) compared with NVF, and the age of achieving these milestones was higher in CBVL than PVF (eg, head holding: 7.33 vs 4.03 years; P < .001). All 4 developmental milestones were associated with the degree of vestibular impairment. This cohort study found that among children with profound HL, vestibular impairment was prevalent, varied according to HL origin, and associated with posturomotor development; while all developmental milestones were associated with vestibular impairment severity, not all HL causes were associated with vestibular impairment severity. Children with profound HL may benefit from complete vestibular assessment before cochlear implantation, which would support early and adapted management, such as physical therapy for CBVL and cochlear implantation strategy.

Balloon predilation or direct valve implantation in TAVI for women: Insights from the DIRECTAVI study.

The randomized DIRECTAVI trial demonstrated safety and feasibility of transcatheter aortic valve implantation (TAVI) without balloon aortic valvuloplasty (BAV) using SAPIEN 3 balloon-expandable devices. However, the female population with smaller anatomy may have potential higher risk of residual gradient and/or mismatch. We assessed the impact of BAV on the procedural success rate and clinical outcomes in the female population of the DIRECTAVI trial. Between May 2016 and May 2018, 91 of the 250 patients included in the DIRECTAVI trial were women (38.6%), 45 of them (49.5%) were enrolled in the BAV group and 46 of them (50.5%) in the direct TAVI group. The primary endpoint was procedural success rate in women (Valve Academic Research Consortium-2 criteria). The secondary endpoint included evaluation of PPM and 1-month major adverse events according to the implantation stategy in women and comparison between men and women regarding major endpoints. The primary endpoint occurred in 29 women (64.4%) in the BAV group and in 34 women (73.9%) in the direct TAVI group (mean difference 9.47%; 95% confidence interval: 6.5%-25.4%; p = 0.045 for non-inferiority of the direct strategy). One-month major adverse events were similar between the 2 women groups. Procedural success was lower in women vs men (p = 0.01) due to higher incidence of moderate mismatches in women (p = 0.001) but with no significant difference regarding the implantation strategy (p = 0.4). Direct implantation of the balloon-expandable SAPIEN 3 valve was non-inferior to predilatation on procedural success in women. Incidence of moderate mismatch was higher in women but was not related to the implantation strategy.

Nickel nitride-mediated nitric oxide generation for combating implant-associated infections

NiTi alloys are widely used in the fabrication of biomedical implants, and it is essential to endow them with selective antibacterial properties to avoid implant-associated infection. In this study, nickel nitride (Ni3N), as a promising new inorganic nitric oxide (NO) donor, was in situ constructed on the surface of NiTi alloys through a straightforward two-step plasma immersion ion implantation (PIII) strategy. Nickel sites were first exposed by physical bombardment with argon or metal plasma, followed by reaction with nitrogen plasma to form Ni3N. Ni3N can disrupt the transmembrane proton electrochemical gradient by capturing protons to produce ammonia species (NHx), resulting in the accumulation of reactive oxygen species (ROS) as a result of bacterial metabolic disruption. On the other hand, the generated NHx can further react with ROS to produce NO and reactive nitrogen species (RNS). As a result, the Ni3N films exhibited more than 99 % antibacterial efficiency against both gram-negative and gram-positive bacteria. They also demonstrated effective antibacterial properties in a rat subcutaneous implant model. In addition, the modified NiTi alloys exhibit good corrosion resistance and cytocompatibility. This study provides a green, safe, and inexpensive method for constructing metal nitride films on implant surfaces and offers new ideas for the clinical design and fabrication of novel antibacterial implants.