Glycan-shielded homodimer structure and dynamical features of the canine distemper virus hemagglutinin relevant for viral entry and efficient vaccination

Canine distemper virus (CDV) belongs to morbillivirus, including measles virus (MeV) and rinderpest virus, which causes serious immunological and neurological disorders in carnivores, including dogs and rhesus monkeys, as recently reported, but their vaccines are highly effective. The attachment glycoprotein hemagglutinin (CDV-H) at the CDV surface utilizes signaling lymphocyte activation molecule (SLAM) and Nectin-4 (also called poliovirus-receptor-like-4; PVRL4) as entry receptors. Although fusion models have been proposed, the molecular mechanism of morbillivirus fusion entry is poorly understood. Here, we determined the crystal structure of the globular head domain of CDV-H vaccine strain at 3.2 Å resolution, revealing that CDV-H exhibits a highly tilted homodimeric form with a six-bladed β-propeller fold. While the predicted Nectin-4-binding site is well conserved with that of MeV-H, that of SLAM is similar but partially different, which is expected to contribute to host specificity. Five N-linked sugars covered a broad area of the CDV-H surface to expose receptor-binding sites only, supporting the effective production of neutralizing antibodies. These features are common to MeV-H, although the glycosylation sites are completely different. Furthermore, real-time observation using high-speed atomic force microscopy revealed highly mobile features of the CDV-H dimeric head via the connector region. These results suggest that sugar-shielded tilted homodimeric structure and dynamic conformational changes are common characteristics of morbilliviruses and ensure effective fusion entry and vaccination.

[A Case of Undifferentiated Sarcoma of the Liver in an Adult Treated with Right Hepatectomy Followed by Adjuvant Chemotherapy]

Undifferentiated sarcoma of the liver is rare, especially in adults, and is an aggressive malignancy that originates from the primary mesenchymal tissues. A 53-year-old man was referred to our hospital for further evaluation of a low-grade fever. Contrast-enhanced CT revealed an 18-cm tumor in the right lobe of the liver. The tumor was characterized by low-density areas suspected of cystic components, a high-density area suspected of hemorrhage, and contrast enhancement in the thickened marginal and internal septa. MRI revealed a high-intensity tumor with a heterogeneous structure on T2-weighted images. Angiosarcoma of the liver with intratumoral hemorrhage was suspected, and right hepatectomy was performed. The pathological diagnosis was an undifferentiated sarcoma based on the presence of undifferentiated mesenchymal tumor cells with a stellate to spindle-shaped pleomorphism. Following a multidisciplinary discussion, 4 courses of the AI regimen (doxorubicin and ifosfamide)were administered as adjuvant chemotherapy, and no recurrence was confirmed at 2 years and 6 months follow-up. Our case suggests that radical resection followed by adjuvant chemotherapy may contribute to a favorable prognosis for undifferentiated sarcoma of the liver.

Demonstration of nuclear gamma-ray polarimetry based on a multi-layer CdTe Compton camera

To detect and track structural changes in atomic nuclei, the systematic study of nuclear levels with firm spin-parity assignments is important. While linear polarization measurements have been applied to determine the electromagnetic character of gamma-ray transitions, the applicable range is strongly limited due to the low efficiency of the detection system. The multi-layer Cadmium-Telluride (CdTe) Compton camera can be a state-of-the-art gamma-ray polarimeter for nuclear spectroscopy with the high position sensitivity and the detection efficiency. We demonstrated the capability to operate this detector as a reliable gamma-ray polarimeter by using polarized 847-keV gamma rays produced by the [Formula: see text]([Formula: see text]) reaction. By combining the experimental data and simulated calculations, the modulation curve for the gamma ray was successfully obtained. A remarkably high polarization sensitivity was achieved, compatible with a reasonable detection efficiency. Based on the obtained results, a possible future gamma-ray polarimetery is discussed.

High-Fat Diet-Induced Diabetic Conditions Exacerbate Cognitive Impairment in a Mouse Model of Alzheimer's Disease Via a Specific Tau Phosphorylation Pattern

BACKGROUND

Epidemiological evidence has demonstrated a clear association between diabetes mellitus and increased risk of Alzheimer's disease (AD). Cerebral accumulation of phosphorylated tau aggregates, a cardinal neuropathological feature of AD, is associated with neurodegeneration and cognitive decline. Clinical and experimental studies indicate that diabetes mellitus affects the development of tau pathology; however, the underlying molecular mechanisms remain unknown.

OBJECTIVE

In the present study, we used a unique diabetic AD mouse model to investigate the changes in tau phosphorylation patterns occurring in the diabetic brain.

DESIGN

Tau-transgenic mice were fed a high-fat diet (n = 24) to model diabetes mellitus. These mice developed prominent obesity, severe insulin resistance, and mild hyperglycemia, which led to early-onset neurodegeneration and behavioral impairment associated with the accumulation of hyperphosphorylated tau aggregates.

RESULTS

Comprehensive phosphoproteomic analysis revealed a unique tau phosphorylation signature in the brains of mice with diabetic AD. Bioinformatic analysis of the phosphoproteomics data revealed putative tau-related kinases and cell signaling pathways involved in the interaction between diabetes mellitus and AD.

CONCLUSION

These findings offer potential novel targets that can be used to develop tau-based therapies and biomarkers for use in AD.

Proof-of-Principle Experiment for Testing Strong-Field Quantum Electrodynamics with Exotic Atoms: High Precision X-Ray Spectroscopy of Muonic Neon

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst)  eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

Formation of subcellular compartments by condensation-prone protein OsJAZ2 in Oryza sativa and Nicotiana benthamiana leaf cells

OsJAZ2 protein has a propensity to form condensates, possibly by multivalent interactions, and can be used to construct artificial compartments in plant cells. Eukaryotic cells contain various membraneless organelles, which are compartments consisting of proteinaceous condensates formed by phase separation. Such compartments are attractive for bioengineering and synthetic biology, because they can modify cellular function by the enrichment of molecules of interest and providing an orthogonal reaction system. This study reports that Oryza sativa JAZ2 protein (OsJAZ2) is an atypical jasmonate signalling regulator that can form large condensates in both the nucleus and cytosol of O. sativa cells. TIFY and Jas domains and low-complexity regions contribute to JAZ2 condensation, possibly by multivalent interaction. Fluorescence recovery after photobleaching (FRAP) analysis suggests that JAZ2 condensates form mostly gel-like or solid compartments, but can also be in a liquid-like state. Deletion of the N-terminal region or the TIFY domain of JAZ2 causes an increase in the mobile fraction of JAZ2 condensates, moderately. Moreover, JAZ2 can also form liquid-like condensates when expressed in Nicotiana benthamiana cells. The recombinant JAZ2 fused to the green fluorescent protein (GFP) forms condensate in vitro, suggesting that the intermolecular interaction of JAZ2 molecules is a driving force for condensation. These results suggest the potential use of JAZ2 condensates to construct artificial membraneless organelles in plant cells.

The Japan-Multimodal Intervention Trial for Prevention of Dementia (J-MINT): The Study Protocol for an 18-Month, Multicenter, Randomized, Controlled Trial

Background/Objectives

The Japan-multimodal intervention trial for prevention of dementia (J-MINT) is intended to verify the effectiveness of multi-domain interventions and to clarify the mechanism of cognitive improvement and deterioration by carrying out assessment of dementia-related biomarkers, omics analysis and brain imaging analysis among older adults at high risk of dementia. Moreover, the J-MINT trial collaborates with partnering private enterprises in the implementation of relevant interventional measures. This manuscript describes the study protocol.

Design/Setting

Eighteen-month, multi-centered, randomized controlled trial.

Participants

We plan to recruit 500 older adults aged 65–85 years with mild cognitive impairment. Subjects will be centrally randomized into intervention and control groups at a 1:1 allocation ratio using the dynamic allocation method with all subjects stratified by age, sex, and cognition.

Intervention

The multi-domain intervention program includes: (1) management of vascular risk factors; (2) group-based physical exercise and self-monitoring of physical activity; (3) nutritional counseling; and (4) cognitive training. Health-related information will be provided to the control group every two months.

Measurements

The primary and secondary outcomes will be assessed at baseline, 6-, 12-, and 18-month follow-up. The primary outcome is the change from baseline to 18 months in a global composite score combining several neuropsychological domains. Secondary outcomes include: cognitive change in each neuropsychological test, incident dementia, changes in blood and dementia-related biomarkers, changes in geriatric assessment including activities of daily living, frailty status and neuroimaging, and number of medications taken.

Conclusions

This trial that enlist the support of private enterprises will lead to the creation of new services for dementia prevention as well as to verify the effectiveness of multi-domain interventions for dementia prevention.

Electronic Supplementary Material

Supplementary material is available for this article at 10.14283/jpad.2021.29 and is accessible for authorized users.

High-resolution spatiotemporal transcriptome analyses during cellularization of rice endosperm unveil the earliest gene regulation critical for aleurone and starchy endosperm cell fate specification

The major tissues of the cereal endosperm are the starchy endosperm (SE) in the inner and the aleurone layer (AL) at the outer periphery. The fates of the cells that comprise these tissues are determined according to positional information; however, our understanding of the underlying molecular mechanisms remains limited. Here, we conducted a high-resolution spatiotemporal analysis of the rice endosperm transcriptome during early cellularization. In rice, endosperm cellularization proceeds in a concentric pattern from a primary alveolus cell layer, such that developmental progression can be defined by the number of cell layers. Using laser-capture microdissection to obtain precise tissue sections, transcriptomic changes were followed through five histologically defined stages of cellularization from the syncytial to 3-cell layer (3 L) stage. In addition, transcriptomes were compared between the inner and the outermost peripheral cell layers. Large differences in the transcriptomes between stages and between the inner and the peripheral cells were found. SE attributes were expressed at the alveolus-cell-layer stage but were preferentially activated in the inner cell layers that resulted from periclinal division of the alveolus cell layer. Similarly, AL attributes started to be expressed only after the 2 L stage and were localized to the outermost peripheral cell layer. These results indicate that the first periclinal division of the alveolus cell layer is asymmetric at the transcriptome level, and that the cell-fate-specifying positional cues and their perception system are already operating before the first periclinal division. Several genes related to epidermal identity (i.e., type IV homeodomain-leucine zipper genes and wax biosynthetic genes) were also found to be expressed at the syncytial stage, but their expression was localized to the outermost peripheral cell layer from the 2 L stage onward. We believe that our findings significantly enhance our knowledge of the mechanisms underlying cell fate specification in rice endosperm.

P–156 Automatic pronuclear detection based on deep learning technology has clinical utility

Study question

Does the performance of an automatic pronuclear detection system based on deep learning technology have clinical utility?

Summary answer

Output results for 2PN detection using the automatic system powered by deep learning technology has clinical utility.

What is known already

In order to establish a more objective embryo evaluation system, we have been developing an automatic pronuclear detection system that utilizes deep learning technology based on Time- Lapse (TL) images. We have previously reported that the accuracy of pronuclei detection was improved by introducing an analysis method using 11 slices in the Z axis. In this study, we evaluated the potential clinical practicality of the automatic pronuclear detection system.

Study design, size, duration

Embryos clinically evaluated between May 2018 and December 2019 by embryologists were chosen for this study. We prepared for analysis TL videos of 995 embryos that had been evaluated as having 0, 1, 2, and 3PN.

Participants/materials, setting, methods

Part1:We compared the outputs of the automatic pronuclear detection system with these embryologists(three junior embryologists (1a), three intermediate embryologists (1b),and three senior embryologists (1c)) who had judged the pronuclei number from TL videos from 40 embryos each having 0,1,2,and 3PN.

Part2:The automatic pronuclear detection system determined the pronuclei number from the TL videos of 955 embryos scored as either 1,2,and 3PN,(different from those used in Part1),and the detection rate for 2PN was calculated.

Main results and the role of chance

Part1: The sensitivities for embryologist groups 1a),1b),1c) and the automatic pronuclear detection system were 80.0%,100%,100%,100% for 2PN, 60.0%,83.3%,86.7%,100% for 0PN, 46.7%,80.0%,86.7%,10.0% for 1PN, and 73.3%,96.7%,96.7%,10.0% for 3PN.

Part2: The precision for 2PN by the automatic pronuclear detection system was 99%.

Limitations, reasons for caution

In order to further improve the performance of the automatic pronuclear detection system, further adjustment of the algorithm and more training images will be utilised.

Wider implications of the findings: The detection of 2PN by the automatic pronuclear detection system was highly reliable, and the performance of the system was comparable to that of embryologists. These first results are reassuring and support the clinical use of the system as a further aid for embryologists, in routine laboratory practice.

Trial registration number

‘not applicable’

Deexcitation Dynamics of Muonic Atoms Revealed by High-Precision Spectroscopy of Electronic K X Rays

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kβ x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

Acetic-acid-induced jasmonate signaling in root enhances drought avoidance in rice

Conferring drought resistant traits to crops is one of the major aims of current breeding programs in response to global climate changes. We previously showed that exogenous application of acetic acid to roots of various plants could induce increased survivability under subsequent drought stress conditions, but details of the metabolism of exogenously applied acetic acid, and the nature of signals induced by its application, have not been unveiled. In this study, we show that rice rapidly induces jasmonate signaling upon application of acetic acid, resulting in physiological changes similar to those seen under drought. The major metabolite of the exogenously applied acetic acid in xylem sap was determined as glutamine-a common and abundant component of xylem sap-indicating that acetic acid is not the direct agent inducing the observed physiological responses in shoots. Expression of drought-responsive genes in shoot under subsequent drought conditions was attenuated by acetic acid treatment. These data suggest that acetic acid activates root-to-shoot jasmonate signals that partially overlap with those induced by drought, thereby conferring an acclimated state on shoots prior to subsequent drought.

Ultrafast Creation of Overlapping Rydberg Electrons in an Atomic BEC and Mott-Insulator Lattice

We study an array of ultracold atoms in an optical lattice (Mott insulator) excited with a coherent ultrashort laser pulse to a state where single-electron wave functions spatially overlap. Beyond a threshold principal quantum number where Rydberg orbitals of neighboring lattice sites overlap with each other, the atoms efficiently undergo spontaneous Penning ionization resulting in a drastic change of ion-counting statistics, sharp increase of avalanche ionization, and the formation of an ultracold plasma. These observations signal the actual creation of electronic states with overlapping wave functions, which is further confirmed by a significant difference in ionization dynamics between a Bose-Einstein condensate and a Mott insulator. This system is a promising platform for simulating electronic many-body phenomena dominated by Coulomb interactions in the condensed phase.

Phase II multi-institutional prospective trial of nab-paclitaxel as second-line chemotherapy for advanced gastric cancer refractory to fluoropyrimidine with modified dose reduction criteria (CCOG1303)

BACKGROUND

The aim of this study was to explore the efficacy and safety of nab-paclitaxel as second-line chemotherapy for advanced gastric cancer with modified dose reduction criteria by which the doses were manipulated earlier.

METHODS

Gastric cancer patients who developed progression during the fluoropyrimidine-containing first-line chemotherapy were assigned to receive nab-paclitaxel (260 mg/m²) by triweekly administration. Dose reduction was regulated according to predefined toxicity criteria which included neutropenia less than 1000/mm³ and/or peripheral sensory neuropathy of grade 2 or more. The primary endpoint was progression-free survival.

RESULTS

A total of 50 patients were enrolled, 47 of whom were eligible for efficacy analyses. The median number of treatment cycles and relative dose intensity given per patient was four (range 1-25), and 90% (range 60-100). Of total administration throughout the trial of 280 cycles, dose reduction was required in 50 cycles. The median progression-free survival was 3.5 months (95% confidence interval 2.5-4.4) that met the primary endpoint. The median overall survival was 9.0 months (95% confidence interval 6.8-11.8), overall response rate was 16% (95% confidence interval 2-30), and disease control rate was 72% (95% confidence interval 54-90). The median time to treatment failure was 3.5 months (95% confidence interval 2.5-4.4). Adverse events of grade 3 or worse included neutropenia in 49%, and peripheral sensory neuropathy in 11%. Febrile neutropenia occurred only in one patient (2%).

CONCLUSION

The modified dose reduction criteria for triweekly administration of nab-paclitaxel resulted in decreased incidence of severe peripheral sensory neuropathy without decline in efficacy.

Slab geometry type cold neutron moderator development based on neutronic study for Riken Accelerator-driven compact Neutron Source (RANS)

Cold neutrons with energy less than several meV are good probes for material research, and they have been available on large neutron facilities, whereas it is not commonly available on compact accelerator-driven neutron source. RIKEN Accelerator-driven Neutron Source (RANS) is a pulsed neutron facility which provides thermal neutrons and high energy neutrons at several MeV. We started a project to implement a cold neutron moderator for RANS to broaden cold neutrons applications. A cold neutron moderator system with a mesitylene moderator at 20K and a polyethylene pre-moderator at room temperature in the slab geometry was designed for RANS. So far, the thickness of the pre-moderator and mesitylene have been optimized to get the highest cold neutron flux by using a Monte Carlo simulation code, PHITS. Graphite reflector dimensions were also proven to have significant effect to increase the cold neutron intensity.

P2477Assessment of intraventricular flow dynamics in acute heart failure studied by Vector Flow Mapping

Background

Although left ventricular (LV) flow dynamics should be closely related to LV morphology and function, little is known about how heart failure (HF) changes it. Pathline Analysis (PA), a recently developed software based on Vector Flow Mapping (VFM, Hitachi), enables us to trace the virtual blood particles entering to the LV in diastole and being ejected in systole. We investigated the change of flow dynamics in HF induced in dogs using PA.

Methods

In 15 open-chest dogs, HF was induced by intracoronary injection of microspheres. Color Doppler images of apical long-axis view were acquired using Prosound F75 (Hitachi) before and after HF and were analyzed by PA. We calculated the ratio of the numbers of entering particles in diastole and ejected particles in systole (ejection rate) and the distance reached by the particles in diastole corrected by the LV long-axis diameter (propagation distance). Apical and basal short axis images were acquired using GE Vivid E9 and were analyzed for peak rotation and peak twist.

Results

After inducing HF, LV end-diastolic pressure increased from 6±2 to 15±5 mmHg (p<0.001) and ejection fraction (EF), apical peak rotation and peak twist decreased significantly (EF; 58±5 to 36±8%, apical peak rotation; 14±5 to 3±2 degree, peak twist; 19±5 to 6±3 degree, p<0.05, respectively). PA showed most of the entering particles to the LV were ejected in the following systole at the control stage, but in HF, a significant part of the entering particles were not ejected and remained in the LV (Figure). Ejection rate decreased from 50±11 to 26±11% (p<0.001) and the propagation distance decreased from 85±9 to 66±13% (p<0.001) after inducing HF. There were significant relationships between indices obtained by PA and EF and peak twist (Table).

Conclusion

A significant part of inflow is not ejected directly to the outflow in the next systole and remains in the LV in HF, suggesting inefficient flow dynamics.

Elliptic neutron-focusing supermirror for illuminating small samples in neutron reflectometry

This paper details the development of a precise assembly of two supermirrors for neutron-focusing, designed for installation in neutron reflectometer SOFIA at BL16 in J-PARC MLF to intensify the illumination for small samples. The supermirrors are sputtered on two metal substrates, whose surfaces are coated with amorphous Ni-P plating, and are figured by diamond cutting and polished to subnanometer roughness. Special care is taken while polishing the substrates to reduce waviness and surface roughness for achieving a sharp focusing spot and uniform neutron reflectivity. The supermirror could converge the neutrons into a focal spot with a width of 0.13 mm in the full width at half maximum.

Zero-energy vortex bound state in the superconducting topological surface state of Fe(Se,Te)

Majorana quasiparticles in condensed matter are important for topological quantum computing^1-3, but remain elusive. Vortex cores of topological superconductors may accommodate Majorana quasiparticles that appear as the Majorana bound state (MBS) at zero energy^4,5. The iron-based superconductor Fe(Se,Te) possesses a superconducting topological surface state^6-9 that was investigated by scanning tunnelling microscopy (STM) studies, which suggest such a zero-energy vortex bound state (ZVBS)^10,11. Here we present ultrahigh energy-resolution spectroscopic imaging (SI)-STM to clarify the nature of the vortex bound states in Fe(Se,Te). We found the ZVBS at 0 ± 20 μeV, which constrained its MBS origin, and showed that some vortices host the ZVBS but others do not. We show that the fraction of vortices hosting the ZVBS decreases with increasing magnetic field and that local quenched disorders are not related to the ZVBS. Our observations elucidate the necessary conditions to realize the ZVBS, which paves the way towards controllable Majorana quasiparticles.

The wheat TdRL1 is the functional homolog of the rice RSS1 and promotes plant salt stress tolerance

Rice rss1 complementation assays show that wheat TdRL1 and RSS1 are true functional homologs. TdRL1 over-expression in Arabidopsis conferred salt stress tolerance and alleviated ROS accumulation. Plants have developed highly flexible adaptive responses to their ever-changing environment, which are often mediated by intrinsically disordered proteins (IDP). RICE SALT SENSITIVE 1 and Triticum durum RSS1-Like 1 protein (TdRL1) are both IDPs involved in abiotic stress responses, and possess conserved D and DEN-Boxes known to be required for post-translational degradation by the APC/C^cdc20 cyclosome. To further understand their function, we performed a computational analysis to compare RSS1 and TdRL1 co-expression networks revealing common gene ontologies, among which those related to cell cycle progression and regulation of microtubule (MT) networks were over-represented. When over-expressed in Arabidopsis, TdRL1::GFP was present in dividing cells and more visible in cortical and endodermal cells of the Root Apical Meristem (RAM). Incubation with the proteasome inhibitor MG132 stabilized TdRL1::GFP expression in RAM cells showing a post-translational regulation. Moreover, immuno-cytochemical analyses of transgenic roots showed that TdRL1 was present in the cytoplasm and within the microtubular spindle of mitotic cells, while, in interphasic cells, it was rather restricted to the cytoplasm with a spotty pattern at the nuclear periphery. Interestingly in cells subjected to stress, TdRL1 was partly relocated into the nucleus. Moreover, TdRL1 transgenic lines showed increased germination rates under salt stress conditions as compared to wild type. This enhanced salt stress tolerance was associated to an alleviation of oxidative damage. Finally, when expressed in the rice rss1 mutant, TdRL1 suppressed its dwarf phenotype upon salt stress, confirming that both proteins are true functional homologs required for salt stress tolerance in cereals.