Search

We present the operation result of a cryogen-free 23.5 T/φ12.5 mm-cold-bore magnet prototype composed of a stack of 12 no-insulation (NI) REBCO single pancake coils-ten middle coils of 6-mm wide and two end coils of 8-mm wide tape-forming 6 double pancake (DP) coils with inner joints. Each coil was wound with the tape having only 1-μm-thick copper layer on each side to overcome the conductor thickness uniformity issue and enhance the mechanical strength within the winding, and then, additional electrical shunting by thin layers of solder was applied on the top and bottom surfaces of each DP coil for effective cooling and quench protection-called extreme-NI winding technique. With this small prototype magnet towards a benchtop 1-GHz NMR, we validate our coil design that include conductor performance, screening-current-induced field and stresses, and conduction-cooling cryogenics. Included in the paper are: 1) conductor issues and our counterproposal in winding; 2) screening-current reduction method; 3) design and manufacture summary of the magnet; and 4) operating test results of the magnet up to 25 Tesla.

Supplementary Methods and References

Supplementary Figure S1. Sequence Alignment of VEGF-Grab1, VEGF-Grab3, and VEGF-Trap; Supplementary Figure S2. Analysis of N-linked Glycosylation for VEGF-Grabs and VEGF-Trap; Supplementary Figure S3. Analysis of O-linked Glycosylation in VEGF-Grab1; Supplementary Figure S4. VEGF-Grab3 displays low binding to tumor ECM; Supplementary Figure S5. Pharmacokinetic profile of VEGF-Grab1 and VEGF-Grab3; Supplementary Figure S6. Tissue accumulation of VEGF-Trap and VEGF-Grab3; Supplementary Figure S7. VEGF-Grabs or VEGF-Trap have no effects on VEGFR2 signalling, EC survival, migration, and tube formation in the absence of VEGFA; Supplementary Figure S8. Dose-dependent Inhibition of VEGFR2 Signalling with Anti-VEGF Therapy; Supplementary Figure S9. Histologic Analyses of Vital Organs after Anti-VEGF Therapy; Supplementary Figure S10. VEGF-Grab effectively suppresses the growth of established bulky macroscopic tumors; Supplementary Figure S11. Histological analyses of the kidney and liver after dose dependent anti-VEGF therapy; Supplementary Figure S12. Combination Therapy of VEGF-Grab3 and Cisplatin Enhances Intratumoral Apoptosis; Supplementary Table S1. Primer sequences for site-directed mutagenesis; Supplementary Table S2. Primer sequences for Quantitative Real Time PCR; Supplementary Table S3. Antibodies.

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by inappropriate hyperglycemia, which causes endothelial dysfunction and peripheral neuropathy, ultimately leading to multiple complications. One prevalent complication is diabetic erectile dysfunction (ED), which is more severe and more resistant to treatment than nondiabetic ED. The serum glycoprotein leucine-rich ɑ-2-glycoprotein 1 (LRG1) is a modulator of TGF-β-mediated angiogenesis and has been proposed as a biomarker for a variety of diseases, including DM. Here, we found that the adhesion GPCR latrophilin-2 (LPHN2) is a TGF-β-independent receptor of LRG1. By interacting with LPHN2, LRG1 promotes both angiogenic and neurotrophic processes in mouse tissue explants under hyperglycemic conditions. Preclinical studies in a diabetic ED mouse model showed that LRG1 administration into the penile tissue, which exhibits significantly increased LPHN2 expression, fully restores erectile function by rescuing vascular and neurological abnormalities. Further investigations revealed that PI3K, AKT, and NF-κB p65 constitute the key intracellular signaling pathway of the LRG1/LPHN2 axis, providing important mechanistic insights into LRG1-mediated angiogenesis and nerve regeneration in DM. Our findings suggest that LRG1 can be a potential new therapeutic option for treating aberrant peripheral blood vessels and neuropathy associated with diabetic complications, such as diabetic ED.

The usefulness of angiogenesis inhibitors as second-line treatment after the progression of anti-epidermal growth factor receptor antibody drug-containing regimens for RAS wild-type metastatic colorectal cancer (mCRC) has not been fully investigated. Therefore, we conducted a phase II study to verify the efficacy and safety of the combination of S-1 and irinotecan plus bevacizumab (SIRB regimen) as second-line treatment for patients with oxaliplatin and cetuximab-refractory KRAS wild-type mCRC.Patients with mCRC who had previously received oxaliplatin and cetuximab-containing regimen were eligible for this study. Patients were infused with bevacizumab 7.5 mg/kg and irinotecan 150 mg/mIn total, 17 patients were enrolled in this study. The 6-month PFS rate was 64.7% [95% confidence interval (CI)=41.99-87.43], median PFS was 10.1 months (95%CI=4.11-17.28), and median overall survival was 21.8 months (95%CI=9.79-37.91). The response rate was 23.5% (95%CI=6.81-49.90%). Grade ≥3 adverse events were observed in 10% of patients, and included leukopenia [3 (17.6%)], neutropenia [5 (29.4%)], anorexia [2 (11.8%)], diarrhea [2 (11.8%)], and hypertension [3 (17.6%)]. No treatment-related deaths or febrile neutropenia were observed.The SIRB regimen might be a promising second-line treatment option for patients with oxaliplatin and cetuximab-refractory KRAS wild-type mCRC in terms of efficacy and safety.

The Golgi apparatus is a critical intracellular organelle that is responsible for modifying, packaging, and transporting proteins to their destinations. Golgi homeostasis involving the acidic pH, ion concentration, and membrane potential, is critical for proper functions and morphology of the Golgi. Although transporters and anion channels that contribute to Golgi homeostasis have been identified, the molecular identity of cation channels remains unknown. Here we identify TMEM87A as a novel Golgi-resident cation channel that contributes to pH homeostasis and rename it as GolpHCat (GolgipH-sensitiveCation channel). The genetic ablation of GolpHCat exhibits an impaired resting pH in the Golgi. Heterologously expressed GolpHCat displays voltage- and pH-dependent, non-selective cationic, and inwardly rectifying currents, with potent inhibition by gluconate. Furthermore, reconstitution of purified GolpHCat in liposomes generates functional channel activities with unique voltage-dependent gating and ion permeation. GolpHCat is expressed in various cell types such as neurons and astrocytes in the brain. In the hippocampus, GolpHCat-knockout mice show dilated Golgi morphology and altered glycosylation and protein trafficking, leading to impaired spatial memory with significantly reduced long-term potentiation. We elucidate that GolpHCat, by maintaining Golgi membrane potential, regulates ionic and osmotic homeostasis, protein glycosylation/trafficking, and brain functions. Our results propose a new molecular target for Golgi-related diseases and cognitive impairment.

TMEM87 family is evolutionarily conserved eukaryotic transmembrane proteins residing in the Golgi1. TMEM87 members play a role in retrograde transport in Golgi and are also proposed mechanosensitive ion channel implicated in cancer and heart disease2–7. In an accompanying study, TMEM87A is described as a voltage-gated, pH-sensitive, non-selective cation channel whose genetic ablation in mice disrupts Golgi morphology, alters glycosylation and protein trafficking, and impairs hippocampal memory. Despite the pivotal functions of TMEM87s in Golgi, underlying molecular mechanisms of channel gating and ion conduction have remained unknown. Here, we present a high-resolution cryo-electron microscopy structure of human TMEM87A (hTMEM87A). Compared with typical ion channels, the architecture of hTMEM87A is unique: a monomeric cation channel consisting of a globular extracellular/luminal domain and a seven-transmembrane domain (TMD) with close structural homology to channelrhodopsin. The central cavity within TMD is occupied by endogenous phosphatidylethanolamine, which seals a lateral gap between two TMs exposed to the lipid bilayer. By combining electrophysiology and molecular dynamics analysis, we identify a funnel-shaped electro-negative luminal vestibule that effectively attracts cations, and phosphatidylethanolamine occludes ion conduction. Our findings suggest that a conformational switch of highly conserved positively-charged residues on TM3 and displacement of phosphatidylethanolamine are opening mechanisms for hTMEM87A, providing an unprecedented insight into the molecular basis for voltage-gated ion conduction in Golgi.

The serum glycoprotein leucine-rich ɑ-2-glycoprotein 1 (LRG1), primarily produced by hepatocytes and neutrophils, is a multifunctional protein that can modulate various signalling cascades, mainly TGFβ signalling. Serum LRG1 and neutrophil-derived LRG1 have different molecular weights due to differences in glycosylation, but what impact the differential glycan composition in LRG1 has on its cellular function is largely unknown. We previously reported that LRG1 can promote both angiogenic and neurotrophic processes under hyperglycemic conditions by interacting with LPHN2. Here, we determined the crystal structure of LRG1, identifying the horseshoe-like solenoid structure of LRG1 and its four N-glycosylation sites. In addition, our biochemical and cell-biological analysis found that de-glycosylation of LRG1, particularly the removal of glycans on N325, is critical for high-affinity binding of LRG1 to LPHN2, thereby promoting LRG1/LPHN2-mediated angiogenic and neurotrophic processes in mouse tissue explants, even under normal glucose conditions. Moreover, intracavernous administration of de-glycosylated LRG1 in a diabetic mouse model ameliorated vascular and neurological abnormalities and restored erectile function. Collectively, these data indicate a novel role of LRG1’s glycans as molecular switches that can tune the range of LRG1’s cellular functions, particularly the LRG1/LPHN2 signalling axis.

TMEM43 is a transmembrane protein with four transmembrane (TM) domains. TheTMEM43gene has been reported to play supportive but critical roles in many human diseases, such as cancer, arrhythmogenic right ventricular cardiomyopathy (ARVC), and auditory neuropathy spectrum disorder (ANSD). However, the direct characterization of the TMEM43 protein is missing. In this study, we examined the function of TMEM43in vitro. Heterologous expression of TMEM43 demonstrated that TMEM43 is permeable to Na+, K+, and Cs+ions, indicating that TMEM43 is a nonselective cation channel. The TMEM43-mediated current decreased gradually with lowering external solution pH, further characterizing TMEM43 as an external-pH sensing channel. Utilizing the endogenous cysteine residue at TM3, we could predict that the pore-forming residue of TMEM43 lies near TM3 and Loop2 domain. Importantly, stochastic channel openings from the lipid bilayer-reconstituted purified TMEM43 protein were observed, strengthening the proposal of TMEM43 as an ion channel. Lastly, the heterologous expression ofTMEM43-p.(Arg372Ter) resulted in a loss of channel activity in a dominant-negative fashion, as in the hearing loss phenotype in humans. These results together disclose the molecular and functional properties of TMEM43 and identify TMEM43 as a novel ion channel. The physiological identity of TMEM43 provided in this study will promote future research on TMEM43-related diseases.

Here, we introduce the nanoparticle-aided cryo-electron microscopy sampling (NACS) method to access the conformational distribution of a protein molecule. Two nanogold particles are labeled at two target sites, and the interparticle distance is measured as a structural parameter via cryo-electron microscopy (cryo-EM). The key aspect of NACS is that the projected distance information instead of the global conformational information is extracted from each protein molecule. This is possible because the contrast provided by the nanogold particles is strong enough to provide the projected distance, while the protein itself is invisible due to its low contrast. We successfully demonstrate that various protein conformations, even for small or disordered proteins, which generally cannot be accessed via cryo-EM, can be captured. The demonstrated method with the potential to directly observe the conformational distribution of such systems may open up new possibilities in studying their dynamics at a single-molecule level.

Osteoporosis and other manifestations of bone disease are frequent in patients with systemic mastocytosis (SM) in association with the presence of mast cell infiltrates in bone marrow, although the mechanisms behind bone disease remain poorly understood. We find that extracellular vesicles (EVs) released by neoplastic mast cells and present in the serum of patients with SM (SM-EVs) block osteoblast differentiation and mineralization in culture, and when injected into mice diminish the expression of osteoblast markers, and trabecular bone volume and microarchitecture. We demonstrate that miRNA-30a and miRNA-23a, increased in SM-EVs and neoplastic mast cell-derived EVs, attenuate osteoblast maturation by suppressing expression of RUNX2 and SMAD1/5, essential drivers of osteogenesis. Thus, SM-EVs carry and deliver miRNAs that epigenetically interfere with bone formation and can contribute to bone mass reduction in SM. These findings also suggest possibilities for novel approaches to the management of bone disease in mast cell proliferative disorders., Osteoporosis and bone disease are common in patients with systemic mastocytosis. Here, the authors show that extracellular vesicles released by neoplastic mast cells of the patients block osteoblast differentiation and bone mineralization when injected into mice, via a mechanism involving suppression of osteogenic factors via miRNA-30a and miRNA-23a.

Lessons Learned The 3-year disease-free survival rate of the twice-daily regimen was not inferior to that of the conventional three-times-daily regimen, and the twice-daily regimen did not lead to an increase in adverse events. The effectiveness of the twice-daily regimen highlights an increased number of treatment options for patients. This will facilitate personalized medicine, particularly for elderly or frail patients who may experience more severe side effects from the combination therapy. Background Tegafur-uracil (UFT)/leucovorin calcium (LV) is an adjuvant chemotherapy treatment for colorectal cancer. We conducted a multicenter randomized trial to assess the noninferiority of a twice-daily compared with a three-times-daily UFT/LV regimen for stage II/III colorectal cancer in an adjuvant setting. Methods Patients were randomly assigned to group A (three doses of UFT [300 mg/m2 per day]/LV [75 mg per day]) or B (two doses of UFT [300 mg/m2 per day]/LV [50 mg per day]). The primary endpoint was 3-year disease-free survival. Results In total, 386 patients were enrolled between July 28, 2011, and September 27, 2013. The 3-year disease-free survival rates of group A (n = 194) and B (n = 192) were 79.4% and 81.4% (95% confidence interval, 72.6–84.4–74.5–85.9), respectively. The most common grade 3/4 adverse events in group A and B were diarrhea (3.9% vs. 7.3%), neutropenia (2.9% vs. 1.6%), increase in aspartate aminotransferase (4.0% vs. 3.9%), increase in alanine aminotransferase (6.2% vs. 6.8%), nausea (1.7% vs. 3.4%), and fatigue (1.1% vs. 2.3%). Conclusion Group B outcomes were not inferior to group A outcomes, and adverse events did not increase.

Many studies have focussed on modulating the activity of γ-aminobutyric acid transaminase (GABA-T), a GABA-catabolizing enzyme, for treating neurological diseases, such as epilepsy and drug addiction. Nevertheless, human GABA-T synthesis and purification have not been established. Thus, biochemical and drug design studies on GABA-T have been performed by using porcine GABA-T mostly and even bacterial GABA-T. Here we report an optimised protocol for overexpression of 6xHis-tagged human GABA-T in human cells followed by a two-step protein purification. Then, we established an optimised human GABA-T (0.5 U/mg) activity assay. Finally, we compared the difference between human and bacterial GABA-T in sensitivity to two irreversible GABA-T inhibitors, gabaculine and vigabatrin. Human GABA-T in homodimeric form showed 70-fold higher sensitivity to vigabatrin than bacterial GABA-T in multimeric form, indicating the importance of using human GABA-T. In summary, our newly developed protocol can be an important first step in developing more effective human GABA-T modulators.

Many natural proteins function in oligomeric forms, which are critical for their sophisticated functions. The construction of protein assemblies has great potential for biosensors, enzyme catalysis, and biomedical applications. In designing protein assemblies, a critical process is to create protein-protein interaction (PPI) networks at defined sites of a target protein. Although a few methods are available for this purpose, most of them are dependent on existing PPIs of natural proteins to some extent. In this report, a metal-chelating amino acid, 2,2'-bipyridylalanine (BPA), was genetically introduced into defined sites of a monomeric protein and used to form protein oligomers. Depending on the number of BPAs introduced into the protein and the species of metal ions (Ni2+ and Cu2+), dimers or oligomers with different oligomerization patterns were formed by complexation with a metal ion. Oligomer sizes could also be controlled by incorporating two BPAs at different locations with varied angles to the center of the protein. When three BPAs were introduced, the monomeric protein formed a large complex with Ni2+. In addition, when Cu2+ was used for complex formation with the protein containing two BPAs, a linear complex was formed. The method proposed in this report is technically simple and generally applicable to various proteins with interesting functions. Therefore, this method would be useful for the design and construction of functional protein assemblies.

Current approaches to design monodisperse protein assemblies require rigid, tight, and symmetric interactions between oligomeric protein units. Herein, we introduce a new multivalent-interaction-driven assembly strategy that allows flexible, spaced, and asymmetric assembly between protein oligomers. We discovered that two polygonal protein oligomers (ranging from triangle to hexagon) dominantly form a discrete and stable two-layered protein prism nanostructure via multivalent interactions between fused binding pairs. We demonstrated that protein nano-prisms with long flexible peptide linkers (over 80 amino acids) between protein oligomer layers could be discretely formed. Oligomers with different structures could also be monodispersely assembled into two-layered but asymmetric protein nano-prisms. Furthermore, producing higher-order architectures with multiple oligomer layers, for example, 3-layered nano-prisms or nanotubes, was also feasible.

Much research in recent years has focused on using empirical machine learning approaches to extract useful insights on the structure-property relationships of superconductor material. Notably, these approaches are bringing extreme benefits when superconductivity data often come from costly and arduously experimental work. However, this assessment cannot be based solely on an open black-box machine learning, which is not fully interpretable, because it can be counter-intuitive to understand why the model may give an appropriate response to a set of input data for superconductivity characteristic analyses, e.g., critical temperature. The purpose of this study is to describe and examine an alternative approach for predicting the superconducting transition temperature $T_c$ from SuperCon database obtained by Japan's National Institute for Materials Science. We address a generative machine-learning framework called Variational Bayesian Neural Network using superconductors chemical elements and formula to predict $T_c$. In such a context, the importance of the paper in focus is twofold. First, to improve the interpretability, we adopt a variational inference to approximate the distribution in latent parameter space for the generative model. It statistically captures the mutual correlation of superconductor compounds and; then, gives the estimation for the $T_c$. Second, a stochastic optimization algorithm, which embraces a statistical inference named Monte Carlo sampler, is utilized to optimally approximate the proposed inference model, ultimately determine and evaluate the predictive performance., Comment: IEEE Transactions on Applied Superconductivity, 2020

This paper presents the results of an electromagnetic design and numerical analysis conducted on a 10-MW-class second-generation high-temperature superconducting generator (2G HTSG) used in an offshore wind power turbine. To report the operation reliability of 10-MW-class HTSGs employed in offshore environment, various electric insulation techniques (EITs) for HTS field coils (FCs), such as no-insulation, metal insulation, and metal-insulator transition insulation, are considered in this study. Using the time-transient solver of the three-dimensional (3D) electromagnetic finite element analysis (FEA), we investigated the electromagnetic characteristics of the HTSG with the three EITs in terms of the electrical output of the HTSG and the critical current of the FCs. To analyze the charging characteristic of the HTS FCs with the three EITs in steady-state operation as well as the electrical in transient-state operation, electric equivalent circuit models are built with key parameters based on the electromagnetic FEA results. Finally, the performances of the HTS FCs are discussed and evaluated in terms of the electromagnetic response and stability characteristics.

High-temperature superconducting (HTS) coil wounds without turn-to-turn insulation (NI coils) present excellent electrical and thermal performance compared to HTS coil wounds with Kapton tape (INS coils). However, NI HTS coils are physically connected to power supplies at room temperature, resulting in increased operating costs due to complex cooling systems and constant heat loads. To overcome this issue, recent studies have investigated alternative charging methods such as flux pump, a power source without any physical contact with the HTS coil at cryogenic temperatures. Even though the NI coil is charged using a flux pump, the disadvantageously slow charge and discharge time remain. In this study, we conducted experiments to compare the charging characteristics of INS and NI coils using a rotary HTS flux pump. A superconducting circuit comprising two coils with equal inductance magnitude is connected in series. From the experiments, we compare the charging characteristics of charging time constant and magnetic field when the same current is applied to the two coils with a power supply and a rotary HTS flux pump. In the NI coil rotary HTS flux pump case, the charging time constant converged to about 6 s in the alternating magnetic field (AMF) above 20 Hz, and the value is similar to the power supply. At 60 Hz and higher AMF, the maximum magnetic field difference from the power supply converged to less than 1%, which appears to be a difference in current and voltage source.

Monoubiquitination of the Fanconi anemia complementation group D2 (FANCD2) protein by the FA core ubiquitin ligase complex is the central event in the FA pathway. FANCA and FANCG play major roles in the nuclear localization of the FA core complex. Mutations of these two genes are the most frequently observed genetic alterations in FA patients, and most point mutations in FANCA are clustered in the C-terminal domain (CTD). To understand the basis of the FA-associated FANCA mutations, we determined the cryo-electron microscopy (EM) structures of Xenopus laevis FANCA alone at 3.35 Å and 3.46 Å resolution and two distinct FANCA–FANCG complexes at 4.59 and 4.84 Å resolution, respectively. The FANCA CTD adopts an arc-shaped solenoid structure that forms a pseudo-symmetric dimer through its outer surface. FA- and cancer-associated point mutations are widely distributed over the CTD. The two different complex structures capture independent interactions of FANCG with either FANCA C-terminal HEAT repeats, or the N-terminal region. We show that mutations that disturb either of these two interactions prevent the nuclear localization of FANCA, thereby leading to an FA pathway defect. The structure provides insights into the function of FANCA CTD, and provides a framework for understanding FA- and cancer-associated mutations.