Treatment of Low-grade Intermediate-risk Nonmuscle-invasive Bladder Cancer With UGN-102 ± Transurethral Resection of Bladder Tumor Compared to Transurethral Resection of Bladder Tumor Monotherapy: A Randomized, Controlled, Phase 3 Trial (ATLAS).

PURPOSE: Low-grade intermediate-risk nonmuscle-invasive bladder cancer is a chronic illness commonly treated by repetitive transurethral resection of bladder tumor. We compared the efficacy and safety of intravesical chemoablation with UGN-102 (a reverse thermal gel containing mitomycin), with or without subsequent transurethral resection of bladder tumor, to transurethral resection of bladder tumor alone in patients with low-grade intermediate-risk nonmuscle-invasive bladder cancer. MATERIALS AND METHODS: This prospective, randomized, phase 3 trial recruited patients with new or recurrent low-grade intermediate-risk nonmuscle-invasive bladder cancer to receive initial treatment with either UGN-102 once weekly for 6 weeks or transurethral resection of bladder tumor. Patients were followed quarterly by endoscopy, cytology, and for-cause biopsy. The primary end point was disease-free survival. All patients were followed for adverse events. RESULTS: Trial enrollment was halted by the sponsor to pursue an alternative development strategy after 282 of a planned 632 patients were randomized to UGN-102 ± subsequent transurethral resection of bladder tumor (n=142) or transurethral resection of bladder tumor monotherapy (n=140), rendering the trial underpowered to perform hypothesis testing. Patients were predominantly male and ≥65 years of age. Tumor-free complete response 3 months after initial treatment was achieved by 92 patients (65%) who received UGN-102 and 89 patients (64%) treated by transurethral resection of bladder tumor. The estimated probability of disease-free survival 15 months after randomization was 72% for UGN-102 ± transurethral resection of bladder tumor and 50% for transurethral resection of bladder tumor (hazard ratio 0.45). The most common adverse events (incidence ≥10%) in the UGN-102 group were dysuria, micturition urgency, nocturia, and pollakiuria. CONCLUSIONS: Primary, nonsurgical chemoablation with UGN-102 for the management of low-grade intermediate-risk nonmuscle-invasive bladder cancer offers a potential therapeutic alternative to immediate transurethral resection of bladder tumor monotherapy and warrants further investigation.

Structural basis of nanobody recognition of grapevine fanleaf virus and of virus resistance loss.

Grapevine fanleaf virus (GFLV) is a picorna-like plant virus transmitted by nematodes that affects vineyards worldwide. Nanobody (Nb)-mediated resistance against GFLV has been created recently, and shown to be highly effective in plants, including grapevine, but the underlying mechanism is unknown. Here we present the high-resolution cryo electron microscopy structure of the GFLV-Nb23 complex, which provides the basis for molecular recognition by the Nb. The structure reveals a composite binding site bridging over three domains of one capsid protein (CP) monomer. The structure provides a precise mapping of the Nb23 epitope on the GFLV capsid in which the antigen loop is accommodated through an induced-fit mechanism. Moreover, we uncover and characterize several resistance-breaking GFLV isolates with amino acids mapping within this epitope, including C-terminal extensions of the CP, which would sterically interfere with Nb binding. Escape variants with such extended CP fail to be transmitted by nematodes linking Nb-mediated resistance to vector transmission. Together, these data provide insights into the molecular mechanism of Nb23-mediated recognition of GFLV and of virus resistance loss.

Total-evidence backbone phylogeny of Aleocharinae (Coleoptera: Staphylinidae).

Phylogenetic studies of Aleocharinae rove beetles, arguably one of the least known and the largest insect lineages, are compromised by its enormous taxonomic diversity. DNA, a powerful resource for phylogenetics, is not available for numerous extant aleocharine species. We provide a broad comparative morphological study of Aleocharinae to frame molecular datasets for total-evidence analyses. Using full-body dissections and slide-mounting techniques for light microscopy supplemented by scanning electron microscopy, we constructed a morphological matrix across all major taxa focused on non-inquiline tribes of Aleocharinae and outgroups. Phylogenetic analyses of this matrix concatenated with earlier published DNA loci and including exemplar taxa lacking molecular data, resolved outstanding controversies and, among other novelties, showed that: the Habrocerinae + Trichophyinae clade is sister group to Aleocharinae; Hypocyphtini are sister to the rest of the "higher Aleocharinae"; Taxicerini are sister to Aleocharini; Hoplandriini and Placusini are nested within a polyphyletic Oxypodini; Hoplandriini are sister to Meoticina; and Actocharini are nested within Liparocephalini. For the first time, morphological synapomorphies are identified for some large clades of Aleocharinae. In addition, 1252 high-resolution microphotographs of aleocharine structures are made available online with the entire matrix for future research.

Cryo-FIB-SEM as a promising tool for localizing proteins in 3D.

Focused Ion Beam-Scanning Electron Microscopy (FIB-SEM) is an invaluable tool to visualize the 3D architecture of cell constituents and map cell networks. Recently, amorphous ice embedding techniques have been associated with FIB-SEM to ensure that the biological material remains as close as possible to its native state. Here we have vitrified human HeLa cells and directly imaged them by cryo-FIB-SEM with the secondary electron InLens detector at cryogenic temperature and without any staining. Image stacks were aligned and processed by denoising, removal of ion beam milling artefacts and local charge imbalance. Images were assembled into a 3D volume and the major cell constituents were modelled. The data illustrate the power of the workflow to provide a detailed view of the internal architecture of the fully hydrated, close-to-native, entire HeLa cell. In addition, we have studied the feasibility of combining cryo-FIB-SEM imaging with live-cell protein detection. We demonstrate that internalized gold particles can be visualized by detecting back scattered primary electrons at low kV while simultaneously acquiring signals from the secondary electron detector to image major cell features. Furthermore, gold-conjugated antibodies directed against RNA polymerase II could be observed in the endo-lysosomal pathway while labelling of the enzyme in the nucleus was not detected, a shortcoming likely due to the inadequacy between the size of the gold particles and the voxel size. With further refinements, this method promises to have a variety of applications where the goal is to localize cellular antigens while visualizing the entire native cell in three dimensions.

Structure-function analyses unravel distinct effects of allosteric inhibitors of HIV-1 integrase on viral maturation and integration.

Recently, a new class of HIV-1 integrase (IN) inhibitors with a dual mode of action, called IN-LEDGF/p75 allosteric inhibitors (INLAIs), was described. Designed to interfere with the IN-LEDGF/p75 interaction during viral integration, unexpectedly, their major impact was on virus maturation. This activity has been linked to induction of aberrant IN multimerization, whereas inhibition of the IN-LEDGF/p75 interaction accounts for weaker antiretroviral effect at integration. Because these dual activities result from INLAI binding to IN at a single binding site, we expected that these activities co-evolved together, driven by the affinity for IN. Using an original INLAI, MUT-A, and its activity on an Ala-125 (A125) IN variant, we found that these two activities on A125-IN can be fully dissociated: MUT-A-induced IN multimerization and the formation of eccentric condensates in viral particles, which are responsible for inhibition of virus maturation, were lost, whereas inhibition of the IN-LEDGF/p75 interaction and consequently integration was fully retained. Hence, the mere binding of INLAI to A125 IN is insufficient to promote the conformational changes of IN required for aberrant multimerization. By analyzing the X-ray structures of MUT-A bound to the IN catalytic core domain (CCD) with or without the Ala-125 polymorphism, we discovered that the loss of IN multimerization is due to stabilization of the A125-IN variant CCD dimer, highlighting the importance of the CCD dimerization energy for IN multimerization. Our study reveals that affinity for the LEDGF/p75-binding pocket is not sufficient to induce INLAI-dependent IN multimerization and the associated inhibition of viral maturation.

3DClusterViSu: 3D clustering analysis of super-resolution microscopy data by 3D Voronoi tessellations.

Motivation: Single-molecule localization microscopy (SMLM) can play an important role in integrated structural biology approaches to identify, localize and determine the 3D structure of cellular structures. While many tools exist for the 3D analysis and visualization of crystal or cryo-EM structures little exists for 3D SMLM data, which can provide unique insights but are particularly challenging to analyze in three dimensions especially in a dense cellular context. Results: We developed 3DClusterViSu, a method based on 3D Voronoi tessellations that allows local density estimation, segmentation and quantification of 3D SMLM data and visualization of protein clusters within a 3D tool. We show its robust performance on microtubules and histone proteins H2B and CENP-A with distinct spatial distributions. 3DClusterViSu will favor multi-scale and multi-resolution synergies to allow integrating molecular and cellular levels in the analysis of macromolecular complexes. Availability and impementation: 3DClusterViSu is available under http://cbi-dev.igbmc.fr/cbi/voronoi3D. Supplementary information: Supplementary figures are available at Bioinformatics online.

The integrative role of cryo electron microscopy in molecular and cellular structural biology.

After gradually moving away from preparation methods prone to artefacts such as plastic embedding and negative staining for cell sections and single particles, the field of cryo electron microscopy (cryo-EM) is now heading off at unprecedented speed towards high-resolution analysis of biological objects of various sizes. This 'revolution in resolution' is happening largely thanks to new developments of new-generation cameras used for recording the images in the cryo electron microscope which have much increased sensitivity being based on complementary metal oxide semiconductor devices. Combined with advanced image processing and 3D reconstruction, the cryo-EM analysis of nucleoprotein complexes can provide unprecedented insights at molecular and atomic levels and address regulatory mechanisms in the cell. These advances reinforce the integrative role of cryo-EM in synergy with other methods such as X-ray crystallography, fluorescence imaging or focussed-ion beam milling as exemplified here by some recent studies from our laboratory on ribosomes, viruses, chromatin and nuclear receptors. Such multi-scale and multi-resolution approaches allow integrating molecular and cellular levels when applied to purified or in situ macromolecular complexes, thus illustrating the trend of the field towards cellular structural biology.

The HIV-1 integrase-LEDGF allosteric inhibitor MUT-A: resistance profile, impairment of virus maturation and infectivity but without influence on RNA packaging or virus immunoreactivity.

BACKGROUND: HIV-1 Integrase (IN) interacts with the cellular co-factor LEDGF/p75 and tethers the HIV preintegration complex to the host genome enabling integration. Recently a new class of IN inhibitors was described, the IN-LEDGF allosteric inhibitors (INLAIs). Designed to interfere with the IN-LEDGF interaction during integration, the major impact of these inhibitors was surprisingly found on virus maturation, causing a reverse transcription defect in target cells. RESULTS: Here we describe the MUT-A compound as a genuine INLAI with an original chemical structure based on a new type of scaffold, a thiophene ring. MUT-A has all characteristics of INLAI compounds such as inhibition of IN-LEDGF/p75 interaction, IN multimerization, dual antiretroviral (ARV) activities, normal packaging of genomic viral RNA and complete Gag protein maturation. MUT-A has more potent ARV activity compared to other INLAIs previously reported, but similar profile of resistance mutations and absence of ARV activity on SIV. HIV-1 virions produced in the presence of MUT-A were non-infectious with the formation of eccentric condensates outside of the core. In studying the immunoreactivity of these non-infectious virions, we found that inactivated HIV-1 particles were captured by anti-HIV-specific neutralizing and non-neutralizing antibodies (b12, 2G12, PGT121, 4D4, 10-1074, 10E8, VRC01) with efficiencies comparable to non-treated virus. Autologous CD4+ T lymphocyte proliferation and cytokine induction by monocyte-derived dendritic cells (MDDC) pulsed either with MUT-A-inactivated HIV or non-treated HIV were also comparable. CONCLUSIONS: Although strongly defective in infectivity, HIV-1 virions produced in the presence of the MUT-A INLAI have a normal protein and genomic RNA content as well as B and T cell immunoreactivities comparable to non-treated HIV-1. These inactivated viruses might form an attractive new approach in vaccine research in an attempt to study if this new type of immunogen could elicit an immune response against HIV-1 in animal models.

X-ray and Cryo-electron Microscopy Structures of Monalysin Pore-forming Toxin Reveal Multimerization of the Pro-form.

ß-Barrel pore-forming toxins (ß-PFT), a large family of bacterial toxins, are generally secreted as water-soluble monomers and can form oligomeric pores in membranes following proteolytic cleavage and interaction with cell surface receptors. Monalysin has been recently identified as a ß-PFT that contributes to the virulence of Pseudomonas entomophila against Drosophila. It is secreted as a pro-protein that becomes active upon cleavage. Here we report the crystal and cryo-electron microscopy structure of the pro-form of Monalysin as well as the crystal structures of the cleaved form and of an inactive mutant lacking the membrane-spanning region. The overall structure of Monalysin displays an elongated shape, which resembles those of ß-pore-forming toxins, such as Aerolysin, but is devoid of a receptor-binding domain. X-ray crystallography, cryo-electron microscopy, and light-scattering studies show that pro-Monalysin forms a stable doughnut-like 18-mer complex composed of two disk-shaped nonamers held together by N-terminal swapping of the pro-peptides. This observation is in contrast with the monomeric pro-form of the other ß-PFTs that are receptor-dependent for membrane interaction. The membrane-spanning region of pro-Monalysin is fully buried in the center of the doughnut, suggesting that upon cleavage of pro-peptides, the two disk-shaped nonamers can, and have to, dissociate to leave the transmembrane segments free to deploy and lead to pore formation. In contrast with other toxins, the delivery of 18 subunits at once, nearby the cell surface, may be used to bypass the requirement of receptor-dependent concentration to reach the threshold for oligomerization into the pore-forming complex.

Structure of the full human RXR/VDR nuclear receptor heterodimer complex with its DR3 target DNA.

Transcription regulation by steroid hormones and other metabolites is mediated by nuclear receptors (NRs) such as the vitamin D and retinoid X receptors (VDR and RXR). Here, we present the cryo electron microscopy (cryo-EM) structure of the heterodimeric complex of the liganded human RXR and VDR bound to a consensus DNA response element forming a direct repeat (DR3). The cryo-EM map of the 100-kDa complex allows positioning the individual crystal structures of ligand- and DNA-binding domains (LBDs and DBDs). The LBDs are arranged perpendicular to the DNA and are located asymmetrically at the DNA 5'-end of the response element. The structure reveals that the VDR N-terminal A/B domain is located close to the DNA. The hinges of both VDR and RXR are fully visible and hold the complex in an open conformation in which co-regulators can bind. The asymmetric topology of the complex provides the structural basis for RXR being an adaptive partner within NR heterodimers, while the specific helical structure of VDR's hinge connects the 3'-bound DBD with the 5'-bound LBD and thereby serves as a conserved linker of defined length sensitive to mutational deletion.

Cryo-electron microscopy structure of lactococcal siphophage 1358 virion.

UNLABELLED: Lactococcus lactis, a Gram(+) lactic acid-producing bacterium used for the manufacture of several fermented dairy products, is subject to infection by diverse virulent tailed phages, leading to industrial fermentation failures. This constant viral risk has led to a sustained interest in the study of their biology, diversity, and evolution. Lactococcal phages now constitute a wide ensemble of at least 10 distinct genotypes within the Caudovirales order, many of them belonging to the Siphoviridae family. Lactococcal siphophage 1358, currently the only member of its group, displays a noticeably high genomic similarity to some Listeria phages as well as a host range limited to a few L. lactis strains. These genomic and functional characteristics stimulated our interest in this phage. Here, we report the cryo-electron microscopy structure of the complete 1358 virion. Phage 1358 exhibits noteworthy features, such as a capsid with dextro handedness and protruding decorations on its capsid and tail. Observations of the baseplate of virion particles revealed at least two conformations, a closed and an open, activated form. Functional assays uncovered that the adsorption of phage 1358 to its host is Ca(2+) independent, but this cation is necessary to complete its lytic cycle. Taken together, our results provide the complete structural picture of a unique lactococcal phage and expand our knowledge on the complex baseplate of phages of the Siphoviridae family. IMPORTANCE: Phages of Lactococcus lactis are investigated mainly because they are sources of milk fermentation failures in the dairy industry. Despite the availability of several antiphage measures, new phages keep emerging in this ecosystem. In this study, we provide the cryo-electron microscopy reconstruction of a unique lactococcal phage that possesses genomic similarity to particular Listeria phages and has a host range restricted to only a minority of L. lactis strains. The capsid of phage 1358 displays the almost unique characteristic of being dextro handed. Its capsid and tail exhibit decorations that we assigned to nonspecific sugar binding modules. We observed the baseplate of 1358 in two conformations, a closed and an open form. We also found that the adsorption to its host, but not infection, is Ca(2+) independent. Overall, this study advances our understanding of the adhesion mechanisms of siphophages.

Protein Delivery System Containing a Nickel-Immobilized Polymer for Multimerization of Affinity-Purified His-Tagged Proteins Enhances Cytosolic Transfer.

Recombinant proteins with cytosolic or nuclear activities are emerging as tools for interfering with cellular functions. Because such tools rely on vehicles for crossing the plasma membrane we developed a protein delivery system consisting in the assembly of pyridylthiourea-grafted polyethylenimine (πPEI) with affinity-purified His-tagged proteins pre-organized onto a nickel-immobilized polymeric guide. The guide was prepared by functionalization of an ornithine polymer with nitrilotriacetic acid groups and shown to bind several His-tagged proteins. Superstructures were visualized by electron and atomic force microscopy using 2 nm His-tagged gold nanoparticles as probes. The whole system efficiently carried the green fluorescent protein, single-chain antibodies or caspase 3, into the cytosol of living cells. Transduction of the protease caspase 3 induced apoptosis in two cancer cell lines, demonstrating that this new protein delivery method could be used to interfere with cellular functions.

Sampling and curation of rove beetles (Insecta, Coleoptera, Staphylinidae) for comprehensive and DNA-grade collections to enhance biodiversity exploration in Northern Eurasia.

Staphylinidae beetles form a major portion of terrestrial biodiversity globally and, in particular, in Northern Eurasia, a large area with a historically better known north temperate, subarctic and arctic biota. However, even here, rove beetles remain amongst the so-called "dark taxa" with a high fraction of taxonomically unknown lineage diversity. The propagation of DNA-based technologies in systematic entomology in recent decades has brought new opportunities for biodiversity exploration, true also for Staphylinidae. Simultaneously, new methods have revealed limitations of specimens sampled and curated by traditional practices, as existing legacy collections, whether institutional or private, unfortunately do not always qualify as a source of DNA-grade material. In addition, both legacy and newly-collected DNA-grade material of Staphylinidae remain highly biased towards Central Europe, a region with a traditionally well-developed scientific infrastructure and long-established culture for the maintenance of entomological collections. To increase the degree of biodiversity knowledge for our target organismal group across the globe, efficient sampling of DNA-grade material and, in particular, the development of comprehensive local collections in under-studied regions is highly desirable. To facilitate that, here we provide a practical guide for collecting and curation of Staphylinidae with a focus on capacity building for DNA-grade collections in Siberia and elsewhere in Northern Eurasia.

CryoEM structure and assembly mechanism of a bacterial virus genome gatekeeper.

Numerous viruses package their dsDNA genome into preformed capsids through a portal gatekeeper that is subsequently closed. We report the structure of the DNA gatekeeper complex of bacteriophage SPP1 (gp612gp1512gp166) in the post-DNA packaging state at 2.7 Å resolution obtained by single particle cryo-electron microscopy. Comparison of the native SPP1 complex with assembly-naïve structures of individual components uncovered the complex program of conformational changes leading to its assembly. After DNA packaging, gp15 binds via its C-terminus to the gp6 oligomer positioning gp15 subunits for oligomerization. Gp15 refolds its inner loops creating an intersubunit ß-barrel that establishes different types of contacts with six gp16 subunits. Gp16 binding and oligomerization is accompanied by folding of helices that close the portal channel to keep the viral genome inside the capsid. This mechanism of assembly has broad functional and evolutionary implications for viruses of the prokaryotic tailed viruses-herpesviruses lineage.

Identification of recurrent pathogenic alleles using exome sequencing data: Proof-of-concept study of Russian subjects.

Whole exome sequencing (WES) is a powerful tool for the cataloguing of population-specific genetic diseases. Within this proof-of-concept study we evaluated whether analysis of a small number of individual exomes is capable of identifying recurrent pathogenic alleles. We considered 106 exomes of subjects of Russian origin and revealed 13 genetic variants, which occurred more than twice and fulfilled the criteria for pathogenicity. All these alleles turned out to be indeed recurrent, as revealed by the analysis of 1045 healthy Russian donors. Eight of these variants (NAGA c.973G>A, ACADM c.985A>C, MPO c.2031-2A>C, SLC3A1 c.1400T>C, LRP2 c.6160G>A, BCHE c.293A>G, MPO c.752T>C, FCN3 c.349delC) are non-Russian-specific, as their high prevalence was previously demonstrated in other European populations. The remaining five disease-associated alleles appear to be characteristic for subjects of Russian origin and include CLCN1 c.2680C>T (myotonia congenita), DHCR7 c.453G>A (Smith-Lemli-Opitz syndrome), NUP93 c.1162C>T (steroid-resistant nephrotic syndrome, type 12), SLC26A2 c.1957T>A (multiple epiphyseal dysplasia) and EIF3F c.694T>G (mental retardation). These recessive disease conditions may be of particular relevance for the Russian Federation and other countries with a significant Slavic population.

Urethral leiomyoma: A rare neoplasm.

Extrauterine leiomyoma is a rare benign tumor, originating from smooth muscle cells, most often localized in the uterus. Extrauterine localization of leiomyoma is extremely rare. The presence of a neoplasm near the urethra always poses a challenge for differential diagnosis. Variety of pathologies sharing similar clinical findings requires further diagnostic testing and doctor alertness. We present the clinical case of urethral leiomyoma in a female patient aged 42 years complaining of frequent urination and vulval mass. The patient underwent neoplasm removal with further histologic examination revealing urethral leiomyoma. The article features the diagnosis and treatment of this rare pathology.

Cystic Prostatic Carcinoma - A Clinical Case and Literature Review.

Cystic formations in the prostate are quite common, but the vast majority are benign. The cystic form of prostate adenocarcinoma can present unexpected symptoms, and management can be difficult because of the local advanced stage of the disease. A unique feature of this case is the surgical local cancer treatment. In this clinical case, we describe the literature surrounding this rare form of neoplasm. We present a clinical case of a rare form of prostate cancer in a 71-year-old male who was admitted to ER with acute urinary retention. A huge obstructing prostatic cyst was revealed. After successful trial-without-catheter, the patient underwent transperineal cyst draining and this restored urination. PSAt was increased up to 55 ng/mL. The cystic wall biopsy revealed adenocarcinoma with a Gleason score of 8 (4+4) (Gleason Group IV), and distant metastasis was noticed with PSMA PET/CT. The patient started androgen deprivation therapy (ADT) with excellent PSA dynamics in three months. Because of lower urinary tract symptoms, he needed local treatment and underwent radical prostatectomy. A three-month follow-up demonstrated a common post-operative period, mild stress incontinence, and PSAt 0.004 ng/mL. Cystic prostatic carcinoma can manifest as urinary retention and be mistakenly taken for a benign obstructing prostate cyst. Despite the locally advanced tumor, it can be successfully treated locally in highly selected patients.

Corrigendum: A new genus and species of Staphylininae rove beetle from the Peruvian Amazon (Coleoptera, Staphylinidae). https://doi.org/10.3897/zookeys.904.48592.

[This corrects the article DOI: 10.3897/zookeys.904.48592.].

A new genus and species of Staphylininae rove beetle from the Peruvian Amazon (Coleoptera, Staphylinidae).

A new monotypic genus of Staphylininae Latreille, 1802 tribe incertae sedis is proposed based on Amazonothops aslaki gen. et sp. nov. from the Peruvian Amazon. Descriptions and illustrations of the new genus and species are provided. Its systematic placement and phylogenetic significance are discussed.

Design of a RF-resonant set improving locally the B1+ efficiency. Applications for clinical MRI in andrology and urology.

Modern diagnostic imaging methods for andrology and urology fall behind other well-developed applications such as cardiology or neurology. Particularly, MRI despite its superior soft tissue contrast is hardly used for MR-imaging of the penis, primarily due to the lack of the corresponding receive or transmit coils. In order to fix this, a new radio frequency resonator, based on the birdcage operating principles has been designed, simulated, fabricated, tested and compared experimentally to existing RF coils. In order to provide high transmit efficiency and high sensitivity, while maintaining the coil safety, the resonator spatially separates alternating magnetic and electric fields. The transmitted magnetic field (B1+) is concentrated in the centre of the imaging volume, while the electric field remains on its edge and does not lead to tissue heating. The resonator design was optimised for human MRI in 1.5 T scanners. Both simulations and experiment showed the resonator to provide around 100-fold specific absorption rate reduction, around 10-fold improvement of the transmit efficiency and more than 10-fold enhancement of the signal to noise ratio (SNR) in a phantom compared to the body coil, around 2-fold SNR enhancement in a phantom compared to the commercial flexible 4-element coil, and up to 1.5-fold enhancement compared to the same coil in-vivo.