Minimally invasive transcatheter embolization is a common nonsurgical procedure in interventional radiology. It is used for the deliberate occlusion of blood vessels for the treatment of disease or ...injured vasculature, including vascular malformation and malignant/benign tumors. Here, we introduce a gel embolic agent comprising chitosan nanofibers and nanoclay with excellent catheter injectability and tunable mechanical properties for embolization. The properties of the gel were optimized by varying the ratio between each individual component and also adjusting the total solid content. The rheological studies confirm the shear thinning property and gel nature of the developed gel as well as their recoverability. Injection force was measured to record the force required to pass the embolic gel through a clinically relevant catheter, evaluating for practicality of hand‐injection. Theoretical predicted injection force was calculated to reduce the development time and to enhance the physician's experience. The stability of occlusion was also tested in vitro by monitoring the pressure required to displace the gel. The engineered gels exhibited sterility, hemocompatibility and cell biocompatibility, highlighting their potential for transcatheter embolization.
A shear thinning hydrogel embolic material comprising laponite nanoclay and chitosan nanofibers was developed, characterized, and studied for transcatheter based minimally invasive surgery. The developed gels exhibited tunable rheological properties which is beneficial for a wide range of embolization conditions and the injection force of the gel through a catheter was measured as well as predicted using rheological parameters for improving the physician's experience. The engineered embolic gels demonstrated exceptional in vitro stability to withstand physiological blood pressure, along with excellent sterility, hemo‐ and bio‐compatibility, highlighting the potential application for catheter‐directed arterial embolization.
A biodegradable, dual functional drug delivery system with superparamagnetic property (Ms: 50.1 emu g−1) for magnetic hyperthermia and tumour-specific pH-dependent drug delivery (loading capacity: ...58 μg mg−1) has been designed with magnetically modulated nanocellulose. Increased site-specific bioavailability, effective magnetic hyperthermia potential and pH-responsive controlled release of Doxorubicin (Dox) have been accomplished with a single system, and hence, it is proposed as a multimodal therapeutic tool.
Display omitted
•pH responsive Dox release system from phosphorylated nanocellulose & superparamagnetic Fe3O4 nanoparticles PNC-IO-Dox.•PNC-IO-Dox exhibits Ms of 58 emu g−1 and is capable of eliciting magnetic hyperthermia potential.•PNC-IO-Dox is biocompatible and having significant internalization efficiency and favourable apoptotic mechanism.
Highlights • Explores cortical activity associated with the control of human stepping. • Cortical potentials precede the onset of predictive balance control as well as foot-off. • Event-related ...desynchronization of mu and beta rhythm during MRPs. • Work highlights cortical events linked to automatic control of balance.
The battle against the COVID-19 pandemic counters the waste management system, as billions of single-use face masks are used per day all over the world. Proper disposal of used face masks without ...jeopardizing the health and the environment is a challenge. Herein, a novel method for recycling of medical face masks has been studied. This method incorporates the nonwoven polypropylene (PP) fiber, which is taken off from the mask after disinfecting it, with acrylonitrile butadiene rubber (NBR) using maleic anhydride as the compatibilizer, which results in a PP–NBR blend with a high percentage economy. The PP–NBR blends show enhanced thermomechanical properties among which, 70 wt % PP content shows superior properties compared to other composites with 40, 50, and 60 wt % of PP. The fully Atomistic simulation of PP-NBR blend with compatibilizer shows an improved tensile and barrier properties, which is in good agreement with the experimental studies. The molecular dynamics simulation confirms that the compatibility between non-polar PP and polar NBR phases are vitally important for increasing the interfacial adhesion and impeding the phase separation.
Shear-thinning materials have held considerable promise as embolic agents due to their capability of transition between solid and liquid state. In this study, a laponite nanoclay (NC)/alginate gel ...embolic agent was developed, characterized, and studied for transcatheter based minimally invasive procedures. Both NC and alginate are biocompatible and FDA-approved. Due to electrostatic interactions, the NC/alginate gels exhibit shear-thinning properties that are desirable for transcatheter delivery. The unique shear-thinning nature of the NC/alginate gel allows it to function as a fluid-like substance during transcatheter delivery and as a solid-like embolic agent once deployed. To ensure optimal performance and safety in clinical applications, the rheological characteristics were thoroughly investigated to optimize the mechanical properties of the NC/alginate gel, including storage modulus, yield stress/strain, and thixotropy. To improve physicians' experience and enhance the predictability of gel delivery, a combination of experimental and theoretical approaches was used to assess the injection force required for successful delivery of the gel through clinically employed catheters. Overall, NC/alginate gel exhibited excellent stability and tunable injectability by optimizing the composition of each component. These findings highlight the gel's potential as a robust embolic agent for a wide range of minimally invasive procedures.
Display omitted
•A group of nanoclay-alginate gels was developed as shear-thinning embolic agents.•The gels exhibited tunable rheological properties for varying embolization conditions.•Transcatheter injectability was assessed for improved physician experience.•The embolic gels showed good stability, sterility, hemo- and bio-compatibility.
Scrub typhus is a life-threatening zoonotic bacterial infection. In this randomized, controlled trial, combination therapy with doxycycline and azithromycin led to better outcomes than either drug ...alone.
Remotely addressable actuators are of great interest in fields like microrobotics and smart textiles because of their simplicity, integrity, flexibility, and lightweight. However, most of the ...existing actuator systems are composed of complex assemblies and/or offer a low response rate. Here, the actuation performance of a light-driven, highly oriented film based on ultra-high molecular weight polyethylene (UHMW-PE), containing a photo-responsive additive, 2-(2H-benzotriazol-2-yl)-4,6-ditertpentylphenol (BZT), is reported. The material exhibits a fast (<1 s) and reversible photo-induced thermal response upon exposure to UV light, which results in an exceptionally high actuation stress (∼70 MPa) at a low strain (<0.1%). The proposed actuation mechanism originates from light absorption by BZT and energy transfer into heat, in combination with the intrinsic high stiffness (∼80 GPa) and a negative thermal expansion (NTE) of the oriented polymer films. This unique set of properties of this actuator, in particular the very high specific actuation stress, compared to existing organic and inorganic actuators, and the remote optical actuation, promises impact in fields related to soft robotics, composites, medical devices, optics, prosthetics, and smart textiles.
The Ig new antigen receptors (IgNARs) are single-domain antibodies found in the serum of sharks. Here, we report 2.2- and 2.8-Å structures of the type 2 IgNAR variable domains 12Y-1 and 12Y-2. ...Structural features include, first, an Ig superfamily topology transitional between cell adhesion molecules, antibodies, and T cell receptors; and, second, a vestigial complementarity-determining region 2 at the "bottom" of the molecule, apparently discontinuous from the antigen-binding paratope and similar to that observed in cell adhesion molecules. Thus, we suggest that IgNARs originated as cell-surface adhesion molecules coopted to the immune repertoire and represent an evolutionary lineage independent of variable heavy chain/variable light chain type antibodies. Additionally, both 12Y-1 and 12Y-2 form unique crystallographic dimers, predominantly mediated by main-chain framework interactions, which represent a possible model for primordial cell-based interactions. Unusually, the 12Y-2 complementarity-determining region 3 also adopts an extended β-hairpin structure, suggesting a distinct selective advantage in accessing cryptic antigenic epitopes.
Myeloid leukemia in Down syndrome (ML-DS) clonally evolves from transient abnormal myelopoiesis (TAM), a preleukemic condition in DS newborns. To define mechanisms of leukemic transformation, we ...combined exome and targeted resequencing of 111 TAM and 141 ML-DS samples with functional analyses. TAM requires trisomy 21 and truncating mutations in GATA1; additional TAM variants are usually not pathogenic. By contrast, in ML-DS, clonal and subclonal variants are functionally required. We identified a recurrent and oncogenic hotspot gain-of-function mutation in myeloid cytokine receptor CSF2RB. By a multiplex CRISPR/Cas9 screen in an in vivo murine TAM model, we tested loss-of-function of 22 recurrently mutated ML-DS genes. Loss of 18 different genes produced leukemias that phenotypically, genetically, and transcriptionally mirrored ML-DS.
Display omitted
•Genetic and functional analyses of myeloid preleukemia and leukemia in Down syndrome•Non-GATA1 preleukemic mutations are often not required for preleukemia•Previously undescribed transforming hotspot mutation in CSF2RB identified•Loss of function of 18 genes validated in transformation of preleukemia to leukemia
Myeloid leukemia in Down syndrome (ML-DS) evolves from transient abnormal myelopoiesis (TAM). Labuhn et al. show that trisomy 21 and GATA1 mutations are sufficient for the development of TAM. They further identify and functionally validate additional variants that drive TAM to ML-DS transformation.
PDF
