Deep learning model to predict Ki-67 expression of breast cancer using digital breast tomosynthesis

BACKGROUND

Developing a deep learning (DL) model for digital breast tomosynthesis (DBT) images to predict Ki-67 expression.

METHODS

The institutional review board approved this retrospective study and waived the requirement for informed consent from the patients. Initially, 499 patients (mean age: 50.5 years, range: 29-90 years) referred to our hospital for breast cancer were participated, 126 patients with pathologically confirmed breast cancer were selected and their Ki-67 expression measured. The Xception architecture was used in the DL model to predict Ki-67 expression levels. The high Ki-67 vs low Ki-67 expression diagnostic performance of our DL model was assessed by accuracy, sensitivity, specificity, areas under the receiver operating characteristic curve (AUC), and by using sub-datasets divided by the radiological characteristics of breast cancer.

RESULTS

The average accuracy, sensitivity, specificity, and AUC were 0.912, 0.629, 0.985, and 0.883, respectively. The AUC of the four subgroups separated by radiological findings for the mass, calcification, distortion, and focal asymmetric density sub-datasets were 0.890, 0.750, 0.870, and 0.660, respectively.

CONCLUSIONS

Our results suggest the potential application of our DL model to predict the expression of Ki-67 using DBT, which may be useful for preoperatively determining the treatment strategy for breast cancer.

Mass, Spectroscopy, and Two-Neutron Decay of ^{16}Be

The structure and decay of the most neutron-rich beryllium isotope, ^{16}Be, has been investigated following proton knockout from a high-energy ^{17}B beam. Two relatively narrow resonances were observed for the first time, with energies of 0.84(3) and 2.15(5) MeV above the two-neutron decay threshold and widths of 0.32(8) and 0.95(15) MeV, respectively. These were assigned to be the ground (J^{π}=0^{+}) and first excited (2^{+}) state, with E_{x}=1.31(6)  MeV. The mass excess of ^{16}Be was thus deduced to be 56.93(13) MeV, some 0.5 MeV more bound than the only previous measurement. Both states were observed to decay by direct two-neutron emission. Calculations incorporating the evolution of the wave function during the decay as a genuine three-body process reproduced the principal characteristics of the neutron-neutron energy spectra for both levels, indicating that the ground state exhibits a strong spatially compact dineutron component, while the 2^{+} level presents a far more diffuse neutron-neutron distribution.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Prevention of atopic dermatitis in high-risk neonates via different types of moisturizer application: A randomized, blinded, parallel, three-group, phase II trial (PAF study)

BACKGROUND

The effectiveness of moisturizers in preventing infant atopic dermatitis (AD) remains unclear. We previously showed that using 2e moisturizer of commercial moisturizer (Shiseido Japan Co., Ltd.) at least once a day significantly prevented AD in infants as compared with as-needed petroleum jelly. This trial aimed to determine the effectiveness of twice- or once-daily application of Fam's Baby moisturizer (Fam's Inc.) in preventing AD compared with once-daily 2e moisturizer.

METHODS

This trial was a single-centre, three-parallel-group, assessor-blinded, superiority, individually randomized, controlled, phase II trial that was conducted from 25 August 2020 to 28 September 2021. We randomly assigned 60 newborns with at least one parent or sibling who has AD to receive Fam's Baby moisturizer twice daily (Group A) or once daily (Group B), or 2e once daily (Group C) in a 1:1:1 ratio until they were 32 weeks old. The primary outcome was the time of AD onset.

RESULTS

Atopic dermatitis was observed in 11/20 (55%), 5/20 (25%) and 10/20 (50%), infants in Groups A, B and C, respectively. Cumulative incidence values for AD according to the Kaplan-Meier method showed that infants in Group B tended to maintain an intact skin for a longer period than those in Group C (median time, not reached [NR] vs. 212 days, log-rank test, p = 0.064). Cox regression analysis showed that the risk of AD tended to be lower in Group B (hazard ratio with group C as control, 0.36; 95% confidential intervals: 0.12-1.06). No serious adverse events occurred in any of the enrolled infants.

CONCLUSION

Fam's Baby moisturizer may better prevent AD than 2e. Further large-scale trials should be performed to confirm the efficacy of Fam's Baby moisturizer in preventing AD in infants.

Erratum: Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande [Phys. Rev. Lett. 130, 031802 (2023)]

This corrects the article DOI: 10.1103/PhysRevLett.130.031802.

Formate-producing capacity provided by reducing ability of Streptococcus thermophilus nicotinamide adenine dinucleotide oxidase determines yogurt acidification rate

Yogurt is made by fermenting milk with 2 lactic acid bacteria, Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. To comprehensively understand the protocooperation mechanism between S. thermophilus and L. bulgaricus in yogurt fermentation, we examined 24 combinations of cocultures comprising 7 fast- or slow-acidifying S. thermophilus strains with 6 fast- or slow-acidifying L. bulgaricus strains. Furthermore, 3 NADH oxidase (Nox)-deficient mutants (Δnox) and one pyruvate formate-lyase deficient mutant (ΔpflB) of S. thermophilus were used to evaluate the factor that determines the acidification rate of S. thermophilus. The results revealed that the acidification rate of S. thermophilus monoculture determined the yogurt fermentation rates, despite the coexistence of L. bulgaricus, whose acidification rate was either fast or slow. Significant correlation was found between the acidification rate of S. thermophilus monoculture and the amount of formate production. Result using ΔpflB showed that the formate was indispensable for the acidification of S. thermophilus. Moreover, results of the Δnox experiments revealed that formate production required Nox activity, which not only regulated dissolved oxygen, but also the redox potential. The Nox provided the large decrease in redox potential required by pyruvate formate-lyase to produce formate. A highly significant correlation was found between formate accumulation and Nox activity in S. thermophilus. In conclusion, the formate production ability provided by the action of Nox activity determines the acidification rate of S. thermophilus, and consequently, regulates yogurt coculture fermentation.

Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 ( 16.3 ) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0 . 561 - 0.032 + 0.021 using Feldman-Cousins corrected intervals, and Δ m 32 2 = 2 . 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1 . 97 - 0.70 + 0.97 using Feldman-Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP . When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28 . 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

Granular flow experiment using artificial gravity generator at International Space Station

Studying the gravity-dependent characteristics of regolith, fine-grained granular media covering extra-terrestrial bodies is essential for the reliable design and analysis of landers and rovers for space exploration. In this study, we propose an experimental approach to examine a granular flow under stable artificial gravity conditions for a long duration generated by a centrifuge at the International Space Station. We also perform a discrete element simulation of the granular flow in both artificial and natural gravity environments. The simulation results verify that the granular flows in artificial and natural gravity are consistent. Further, regression analysis of the experimental results reveals that the mass flow rate of granular flow quantitatively follows a well-known physics-based law with some deviations under low-gravity conditions, implying that the bulk density of the granular media decreases with gravity. This insight also indicates that the bulk density considered in simulation studies of space probes under low-gravity conditions needs to be tuned for their reliable design and analysis.

First observation of 28O

Subjecting a physical system to extreme conditions is one of the means often used to obtain a better understanding and deeper insight into its organization and structure. In the case of the atomic nucleus, one such approach is to investigate isotopes that have very different neutron-to-proton (N/Z) ratios than in stable nuclei. Light, neutron-rich isotopes exhibit the most asymmetric N/Z ratios and those lying beyond the limits of binding, which undergo spontaneous neutron emission and exist only as very short-lived resonances (about 10-21 s), provide the most stringent tests of modern nuclear-structure theories. Here we report on the first observation of 28O and 27O through their decay into 24O and four and three neutrons, respectively. The 28O nucleus is of particular interest as, with the Z = 8 and N = 20 magic numbers1,2, it is expected in the standard shell-model picture of nuclear structure to be one of a relatively small number of so-called 'doubly magic' nuclei. Both 27O and 28O were found to exist as narrow, low-lying resonances and their decay energies are compared here to the results of sophisticated theoretical modelling, including a large-scale shell-model calculation and a newly developed statistical approach. In both cases, the underlying nuclear interactions were derived from effective field theories of quantum chromodynamics. Finally, it is shown that the cross-section for the production of 28O from a 29F beam is consistent with it not exhibiting a closed N = 20 shell structure.

Some considerations on the dependence to numerical schemes of Lagrangian radionuclide transport models for the aquatic environment

Lagrangian models present several advantages over Eulerian models to simulate the transport of radionuclides in the aquatic environment in emergency situations. A radionuclide release is simulated as a number of particles whose trajectories are calculated along time and thus these models do not require a spatial discretization (although it is always required in time). In this paper we investigate the dependence of a Lagrangian model output with the grid spacing which is used to calculate concentrations from the final distribution of particles, with the number of particles in the simulation and with the interpolation schemes which are required because of the discrete nature of the water circulation data used to feed the model. Also, a Lagrangian model may describe the exchanges of radionuclides between phases (liquid and solid), which is done in terms of transition probabilities. The dependence of these probabilities with time step is analyzed as well. It was found that the optimum grid size used to calculate concentrations should be carefully checked, and that temporal interpolation is more significant than spatial interpolation to obtain a more accurate solution. A method to estimate the number of particles required to have a certain accuracy level is proposed. Finally, it was found that for low sediment concentrations and small radionuclide k_d, exact equations for the transition probabilities should be used; and that phase transitions introduce a stability condition as in Eulerian models.

Multiple Mechanisms in Proton-Induced Nucleon Removal at ∼100 MeV/Nucleon

We report on the first proton-induced single proton- and neutron-removal reactions from the neutron-deficient ^{14}O nucleus with large Fermi-surface asymmetry S_{n}-S_{p}=18.6  MeV at ∼100  MeV/nucleon, a widely used energy regime for rare-isotope studies. The measured inclusive cross sections and parallel momentum distributions of the ^{13}N and ^{13}O residues are compared to the state-of-the-art reaction models, with nuclear structure inputs from many-body shell-model calculations. Our results provide the first quantitative contributions of multiple reaction mechanisms including the quasifree knockout, inelastic scattering, and nucleon transfer processes. It is shown that the inelastic scattering and nucleon transfer, usually neglected at such energy regime, contribute about 50% and 30% to the loosely bound proton and deeply bound neutron removal, respectively. These multiple reaction mechanisms should be considered in analyses of inclusive one-nucleon removal cross sections measured at intermediate energies for quantitative investigation of single-particle strengths and correlations in atomic nuclei.

[Evaluation of the Effectiveness of a Neck Fixation Device for Improving Image Quality in Diffusion-weighted Whole-body Imaging with Background Suppression]

The effectiveness of a neck fixation device to improve the image quality of DWIBS was investigated. Healthy volunteers were examined while chewing with and without a neck fixation device using a 3-T MRI system. Distance of mandibular movement was measured using true-fast imaging of steady-state precession (true FISP). Signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) of DWIBS were measured. Image quality of DWIBS was scored by visual evaluation. These values were compared with and without a neck fixation device. Regarding results, the mandibular displacement and ADC were decreased, and the SNR and visual score were increased by the use of the fixation device. There is a significant difference between with and without a neck fixation device in each measurement. The technique using a neck fixation device helps improve image quality of DWIBS in the head and neck region.

Limited roles of Piezo mechanosensing channels in articular cartilage development and osteoarthritis progression

OBJECTIVE

To investigate the role of Piezo1 and Piezo2 in surgically induced osteoarthritis (OA) in mice.

DESIGN

Male conditional knockout (cKO) mice missing Piezo1 and Piezo2 in the joint using Gdf5-Cre transgenic mice were induced with post-traumatic OA by destabilization of the medial meniscus (DMM) of the right knee joint at 12 weeks of age. The severity of OA was histologically assessed at 24 weeks of age. OA-associated pain was evaluated by static weight bearing analysis. Additionally, articular chondrocytes isolated from cKO mice were exposed to fluid flow shear stress (FFSS) to evaluate the expression of OA-associated genes.

RESULTS

Mice with conditional deletion of Piezo1 and Piezo2 showed normal joint development with no overt histological changes in the knee joint at 12 weeks and 24 weeks. DMM surgery induced moderate to severe OA in both control and cKO mice (median OARSI score: control, 4.67; cKO, 4.23, P = 0.3082), although a few cKO mice showed milder OA. Pain assessment by static weight-bearing analysis suggested Piezo ablation in the joint has no beneficial effects on pain. FFSS increased the expression of OA-related genes both in control and cKO mice to similar extents.

CONCLUSION

Piezo1 and Piezo2 are not essential for normal joint development. Genetic ablation of Piezo channels did not confer evident protective effects on OA progression in mice. In vitro data suggests that different mechanotransducers other than Piezo channels mediate FFSS in mechanical stress-induced gene expression.

Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande

We report a search for cosmic-ray boosted dark matter with protons using the 0.37  megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1  MeV/c^{2} to 300  MeV/c^{2}.

Extended p_{3/2} Neutron Orbital and the N=32 Shell Closure in ^{52}Ca

The one-neutron knockout from ^{52}Ca in inverse kinematics onto a proton target was performed at ∼230  MeV/nucleon combined with prompt γ spectroscopy. Exclusive quasifree scattering cross sections to bound states in ^{51}Ca and the momentum distributions corresponding to the removal of 1f_{7/2} and 2p_{3/2} neutrons were measured. The cross sections, interpreted within the distorted-wave impulse approximation reaction framework, are consistent with a shell closure at the neutron number N=32, found as strong as at N=28 and N=34 in Ca isotopes from the same observables. The analysis of the momentum distributions leads to a difference of the root-mean-square radii of the neutron 1f_{7/2} and 2p_{3/2} orbitals of 0.61(23) fm, in agreement with the modified-shell-model prediction of 0.7 fm suggesting that the large root-mean-square radius of the 2p_{3/2} orbital in neutron-rich Ca isotopes is responsible for the unexpected linear increase of the charge radius with the neutron number.

Receiver circuit improvement of dual frequency-comb ka-band Doppler backscattering system in the large helical device (LHD)

Doppler-backscattering (DBS) has been used in several fusion plasma devices because it can measure the perpendicular velocity of electron density perturbation v_⊥, the radial electric field E_r, and the perpendicular wavenumber spectrum S(k_⊥) with high wavenumber and spatial resolution. In particular, recently constructed frequency comb DBS systems enable observation of turbulent phenomena at multiple observation points in the radial direction. A dual-comb microwave DBS system has been developed for the large helical device plasma measurement. Since it is desirable to control the gain of each frequency-comb separately, a frequency-comb DBS system was developed with a function to adjust the gain of the scattered signal intensity of each channel separately. A correction processing method was also developed to correct the amplitude ratio and the phase difference between the in-phase and quadrature-phase signals of the scattered signals. As a result, the error in Doppler-shift estimation required to observe vertical velocity and the radial electric field was reduced, which enables more precise measurements.

P-153 Oocytes with narrow perivitelline space have poor fertilization and developmental potentials after ICSI

Study question

Do oocytes with narrow perivitelline space have poor clinical outcomes after ICSI?

Summary answer

After ICSI, oocytes with narrow perivitelline space have an increased degeneration rate and decreased rates of 2PN and embryo development.

What is known already

Several studies reported that oocytes with dysmorphologies, such as zona pellucida (ZP) abnormalities and cytoplasmic inclusions (vacuoles, smooth endoplasmic reticulum cluster, refractile bodies), have poor developmental potential in IVF/ICSI. In research on perivitelline space (PVS), many studies have focused on the PVS with fragmentation as well as large PVS. On the other hand, oocytes with narrow perivitelline space (narrow PVS oocytes) are considered to have an immature cytoplasm, but there are few reports on the relationship between narrow PVS oocytes and clinical outcomes. In this study, we retrospectively analyzed the effect of narrow PVS oocytes on ICSI outcomes.

Study design, size, duration

This retrospective single-center study analyzed 11149 MII oocytes that underwent ICSI between January 2018 and October 2021. We observed the PVS of MII oocytes during ICSI, and oocytes with sufficient PVS between the ZP and cytoplasm were determined to be non-narrow PVS oocytes. Oocytes without sufficient PVS from any angle (PVS was observed only around the first polar body) were defined as narrow PVS oocytes.

Participants/materials, setting, methods

After ICSI, oocytes were cultured in ONESTEP medium (NakaMedical, Tokyo, Japan). Embryos that developed into blastocysts were used for single vitrified-warmed blastocyst transfer (SVBT). We compared the rates of degeneration, 2PN, cleavage, blastocyst formation, good-grade (Gardner’s criteria ≥BB) blastocyst, top-grade blastocyst (Gardner’s criteria=AA), and clinical pregnancy (presence of a gestational sac) between oocytes with narrow and non-narrow PVS. Logistic regression analysis with consideration of patient age, BMI, and basal AMH was performed for each outcome.

Main results and the role of chance

Of the 11149 MII oocytes, 570 and 10579 were determined to be narrow and non-narrow PVS oocytes, respectively. Narrow PVS oocytes showed significantly higher degeneration rates (aOR: 1.52, 95% CI: 1.12–2.06, p&lt;0.01) and lower 2PN rates (aOR: 0.77, 95% CI: 0.64–0.93, p&lt;0.01) after ICSI compared to non-narrow PVS oocytes. Furthermore, rates of cleavage (aOR: 0.52, 95% CI: 0.31–0.87, p&lt;0.05), blastocyst formation (aOR: 0.56, 95% CI: 0.45–0.70, p&lt;0.01), good-grade blastocyst formation (aOR: 0.59, 95% CI: 0.46–0.76, p&lt;0.01), and top-grade blastocyst formation (aOR:0.625, 95% CI:0.45–0.86, p&lt;0.01), were significantly lower in the narrow PVS oocytes.

Of the blastocysts developed, 32 and 1439 blastocysts from narrow PVS oocytes and non-narrow PVS oocytes, respectively, were used for SVBT. The clinical pregnancy rate was not significantly different between blastocysts developed from narrow (aOR: 0.52, 95% CI, 0.22–1.22, p = 0.131) and non-narrow PVS oocytes. However, in blastocysts developed from narrow PVS oocytes, clinical pregnancy was confirmed only in top-grade blastocysts (58.8% [10/17]), and blastocysts of other grades did not result in pregnancy (0% [0/15]).

Limitations, reasons for caution

The limitation of this study is that it was a retrospective analysis conducted at a single IVF center. It is necessary to confirm the reproducibility at other facilities because the evaluation of PVS differs among embryologists and IVF centers. Therefore, a prospective multicenter study is needed.

Wider implications of the findings

We found that the narrow PVS oocytes showed poor outcomes after ICSI. While a good pregnancy rate could be expected if a top-grade blastocyst from such oocytes was obtained and transferred, the embryonic development rate of narrow PVS oocytes is low.

Trial registration number

Not applicable

P-215 Use of hyaluronan-based solution as an alternative to polyvinylpyrrolidone to improve blastulation in ICSI

Study question

This study aimed to analyze whether hyaluronan as an alternative to polyvinylpyrrolidone (PVP) for sperm immobilization, aspiration, and injection into the ooplasm improves ICSI outcomes.

Summary answer

The use of hyaluronan solution as an alternative to PVP improves the blastocyst formation rate and good quality blastocyst formation rate compared to PVP.

What is known already

The PVP solution facilitates ICSI procedures, such as sperm immobilization, aspiration, and injection into the ooplasm. However, it has been reported that injection of a small amount of PVP along with the sperm into the ooplasm negatively affects subsequent embryo development. Hyaluronan is a natural component of the extracellular matrix of the cumulus-oocyte complex. Balaban et al. (2003) reported that hyaluronan can replace PVP during ICSI procedures in the early embryo transfer cycle without adversely affecting pregnancy outcomes. This study analyzed whether using hyaluronan-based solution for the ICSI procedure would improves blastocyst development compared with ICSI using PVP.

Study design, size, duration

This retrospective study analyzed clinical medical reports at Takahashi Women’s Clinic, Japan. We included 4002 oocytes retrieved from 411 patients under 39 years of age who underwent ICSI using autologous oocytes between December 2019 and August 2021. Of the oocytes used for ICSI, 1909 underwent sperm aspiration and injection into the ooplasm with hyaluronan (Sperm Slow; Origio), and 2093 oocytes with 7% PVP (NakaMedical). We did not perform preimplantation genetic testing-aneuploidy for any cycles.

Participants/materials, setting, methods

We used PVP droplets for sperm selection under 400× magnification in both groups. In hyaluronan-ICSI, the selected sperm were transferred to a hyaluronan droplet and washed three times. The sperm was then aspirated with hyaluronan, and ICSI was performed. In PVP-ICSI, all procedures were performed using PVP. The ICSI and embryo transfer outcomes were compared between hyaluronan-ICSI and PVP-ICSI by logistic regression analysis considering patient age, BMI, and basal level of anti-mullerian hormone.

Main results and the role of chance

Normal fertilization rates were 74.3% (1556/2093) in PVP-ICSI and 75.5% (1442/1909) in hyaluronan-ICSI. There was no significant difference in the normal fertilization rate between PVP-ICSI and hyaluronan-ICSI groups (p = 0.437, aOR:1.06, 95% CI: 0.92–1.22). We cultured 1323 2PN embryos in PVP-ICSI and 1237 2PN embryos in hyaluronan-ICSI until the blastocyst stage. Blastocyst formation rates were 48.1% for PVP-ICSI and 52.3% for hyaluronan-ICSI, and this difference was statistically significant (aOR, 1.20; 95% CI: 1.02–1.40; p = 0.024). Moreover, the good grade (Gardner criteria ≧BB) blastocyst formation rates were significantly higher in the hyaluronan-ICSI group (36.9% and 41.0%, aOR: 1.21, 95% CI: 1.03–1.42, p = 0.022). During the study period, we performed 163 and 169 cryo-thawed blastocyst transfer cycles in PVP-ICSI and hyaluronan-ICSI, respectively. The clinical pregnancy rate (50.9% vs. 54.4%, aOR: 1.19, 95% CI: 0.77–1.83, p = 0.443) and miscarriage rate (19.3% vs. 13.0%, aOR: 0.66, 95% CI: 0.3–1.44, p = 0.295) after embryo transfer were not significantly different between PVP-ICSI and hyaluronan-ICSI.

Limitations, reasons for caution

The study was conducted at a single IVF center, and the oocytes included in this study were collected from patients aged &lt; 39 years. Embryo transfer result is based on ongoing pregnancy, while the live birth data for all pregnancies are not yet available.

Wider implications of the findings

Hyaluronan facilitates ICSI procedures such as sperm immobilization, aspiration, and injection. Moreover, the hyaluronan improves blastocyst development. The present study indicates that using hyaluronan as an alternative to PVP during the ICSI procedure is recommended.

Trial registration number

not applicable

P-395 Use of a granulocyte-macrophage colony-stimulating factor (GM-CSF)-containing medium for poor-grade blastocyst transfer increases the clinical pregnancy and live birth rates

Study question

Does the post-thaw use of a GM-CSF-containing medium improve blastocyst transfer outcomes in all blastocysts in a frozen-thawed embryo transfer cycle?

Summary answer

The use of a GM-CSF-containing medium at post-thawing especially improves the live birth (LB) rate of morphologically poor blastocysts in a frozen-thawed embryo transfer cycle.

What is known already

GM-CSF, a cytokine secreted by the epithelial cells of the female reproductive tract, plays an important role in embryonic development, implantation, and subsequent development in humans and animals. In humans, GM-CSF increases the blastocyst developmental rate and decreases the chances of miscarriage. Previously, we reported that the use of a GM-CSF-containing medium for blastocyst recovery culture after thawing improves the clinical pregnancy (CP) rate in a frozen-thawed blastocyst transfer cycle (ESHRE, 2019). However, it is unclear whether GM-CSF improves embryo transfer outcomes in all blastocysts. In addition, it is necessary to accumulate information regarding its effects on neonatal outcomes.

Study design, size, duration

We performed a retrospective observational study to compare two groups: a GM-CSF group (GM-CSF-containing medium; SAGE-1step GM-CSF, Cooper Surgical) and a control group (GM-CSF-free medium; ONE STEP Medium, NAKA Medical). We analyzed 566 blastocyst transfer cycles in patients aged 30–39 years who underwent frozen-thawed single embryo transfer at Takahashi Women’s Clinic (Japan) from February 2018 to February 2019. Chromosomal analysis was not performed.

Participants/materials, setting, methods

We used a control medium for blastocyst culture and a Cryotop safety kit for blastocyst vitrification. After thawing, we cultured blastocysts in a GM-CSF-containing medium or control medium for 3–5 h until transfer. Embryo transfer outcomes were compared. We performed the multivariate logistic regression analysis(MVRA) to adjust confounding bias. A subgroup analysis was also performed of morphological grade according to Gardner’s criteria (excellent: ≥AA, good: blastocysts containing B, poor: blastocysts containing C).

Main results and the role of chance

There were no difference in patient background between the two groups. The CP and LB rates in the GM-CSF group and control group were 54.3% vs. 42.6% and 42.9% vs. 31.1%. The MVRA adjusted by confounding factors(patient age, BMI, basal AMH, blastocyst grade, day of vitrification, number of previous failed ETs, and assisted hatching) demonstrated that CP (p = 0.0193; adjusted odds ratio [aOR], 1.55) and LB rate (p = 0.0080; aOR, 1.67) were significantly higher in GM-CSF group than that of control group. Moreover, the CP and LB rates of the GM-CSF group and control group were: excellent-blastocysts at 62.0% vs. 58.8% (p = 0.5955; OR, 1.14), 52.7% vs. 45.6% (p = 0.2466, aOR:1.33), good-blastocysts 52.1% vs. 37.6% (p = 0.0561; OR, 1.80), 38.0% vs. 26.6% (p = 0.1072; OR, 1.69), and poor-blastocysts 38.9% vs. 17.9% (p = 0.0115; OR, 2.92), 25.9% vs. 9.0% (p = 0.0164; OR, 3.56). A GM-CSF-containing medium significantly improved the CP and LB rates of poor-grade blastocysts. There were no significant differences between the GM-CSF group and control group in the male ratio (52.7％ vs. 51.0%, p = 0.8057), pregnancy duration (38.8±1.4 weeks vs. 38.5±1.8 weeks, p = 0.2558), cesarean section rate (38.2% vs. 40.8%, p = 0.6979), birth weight (3133±466g vs. 3037±437g, p = 0.1281), and congenital anomaly rate (0.91% vs. 2.04％, p = 0.6026).

Limitations, reasons for caution

This was a single-center, retrospective study. Chromosomal abnormalities in embryos were not considered; however, the LB rate among babies was analyzed. The basic chemical composition of the culture medium (salt concentration, glucose concentration, etc.) used in the control group was different from that of the GM-CSF-containing medium.

Wider implications of the findings

We found that the use of a GM-CSF-containing medium improved the clinical pregnancy and live birth rates of poor-grade blastocysts without affecting the babies. This may be an effective therapeutic strategy for some patients as it may allow for the effective use of poor-grade euploid blastocysts.

Trial registration number

not applicable

First Application of Mass Measurements with the Rare-RI Ring Reveals the Solar r-Process Abundance Trend at A=122 and A=123

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and β-delayed neutron emission probability, P_{1  n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.

Self-Sustained Divertor Oscillation Driven by Magnetic Island Dynamics in Torus Plasma

A new type of self-sustained divertor oscillation is discovered in the Large Helical Device stellarator, where the peripheral plasma is detached from material diverters by means of externally applied perturbation fields. The divertor oscillation is found to be a self-regulation of an isolated magnetic field structure (the magnetic island) width induced by a drastic change in a poloidal inhomogeneity of the plasma radiation across the detachment-attachment transitions. A predator-prey model between the magnetic island width and a self-generated local plasma current (the bootstrap current) is introduced to describe the divertor oscillation, which successfully reproduces the experimental observations.

Fast B1 Mapping Based on Double-Angle Method with T1 Correction Using Standard Pulse Sequence

Radiofrequency (RF) field (B1) mapping by combining the double-angle method (DAM) and T1 correction was investigated. The signal intensities S1 and S2 acquired by flip angle (FA) α and double FA 2α at short repetition time (TR) were converted to a signal intensity at TR=∞ by T1 correction. Then, these were used for DAM calculation. The T1 values are measured from two different images acquired with different TRs based on the saturation recovery (SR) method preliminarily. The effects of imaging parameters for T1 estimation and measured FA were investigated using CuSO₄-doped water phantoms. A two-dimensional gradient echo type echo planar imaging pulse sequence was used. T1 values obtained by the 2-SR method were underestimated compared to the multipoint inversion recovery method. FA error was less than 5% when the appropriate imaging parameters were used. The acquisition time could be shortened to under 25 s by the use of T1-corrected DAM.

P–145 usefulness of morphokinetic data to predict pregnancy rates of day–6 blastocyst transfers

Study question

Can a scoring model based on morphokinetic data developed to predict pregnancy rates of day–5 blastocyst transfers (KIDSCORE™D5) predict pregnancy rates of day–6 blastocyst transfers?

Summary answer

KIDSCORE™D5 was able to predict the clinical pregnancy rates of embryo transfers done on day 6 with an area under the curve (AUC) of 0.72.

What is known already

KIDSCORE™D5 is a scoring model based on morphokinetic data developed to predict the pregnancy rates of day–5 blastocysts. In 2019, Regnier et al. reported that the AUC of KIDSCORE™D5 for predicting clinical pregnancy rates of day–5 blastocyst transfers was 0.6. However, as KIDSCORE™D5 is constructed based on morphological characteristics and developmental dynamics of day–5 blastocysts, it is unclear whether KIDSCORE™D5 can predict pregnancy rates of day–6 blastocyst transfers. Since there are many cases of day–6 blastocyst transfers, it is important to know if KIDSCORE™D5 can predict pregnancy rates of day–6 blastocyst transfers.

Study design, size, duration

This retrospective single-center study, which included 162 day–5 and 72 day–6 blastocyst transfers, respectively, was conducted at Takahashi Women’s clinic from January to December 2019. Blastocysts derived from 146 patients who underwent intracytoplasmic sperm injection. All blastocysts were cryopreserved and were transferred singly.

Participants/materials, setting, methods

We used EmbryoScope+™ (Vitrolife) for in-vitro culture and calculated KIDSCORE™D5 (ver.3) using Embryoviewer™ (Vitrolife). Blastocyst scoring was done from 1.0 to 9.9. Clinical pregnancy was defined as the presence of a gestational sac confirmed by transvaginal ultrasonography. Statistical analysis was performed with JMP Pro 15.00 (SAS). The relationship between KIDSCORE™D5 and clinical pregnancy was evaluated by the AUC using ROC curve analysis and multivariate analysis adjusted for patient age.

Main results and the role of chance

The mean KIDSCORE™D5 of day–5 and day–6 blastocysts was 7.1±1.7 and 3.7±1.5, respectively. KIDSCORE™D5 of day–6 blastocysts was significantly lower than that of day–5 blastocysts (p &lt; 0.0001, Wilcoxon test). ROC curve analysis showed that the KIDSCORE™D5 could predict clinical pregnancy rates with an AUC of 0.62 for day–5 blastocysts and 0.72 for day–6 blastocysts. The cut-off values for KIDSCORE™D5 were 5.7 and 4.9 for day–5 and day–6 blastocysts, respectively. Blastocysts above the cut off value on both day–5 and day–6 had a significantly higher pregnancy rate than those below the cut off value (day–5: 61.9% vs. 33.3%(p = 0.0023), day–6: 47.4% vs. 7.6%(p = 0.0003)). Multivariate analysis adjusted for patient age showed that KIDSCORE™D5 correlated with clinical pregnancy rates of days 5 and 6 of blastocyst transfer with AUCs of 0.66 and 0.73, respectively.

Limitations, reasons for caution

This study had a small sample size, and it was a retrospective single-center study. In addition, the relationship between KIDSCORE™D5 and clinical pregnancy rates may vary among facilities. Therefore, a prospective multicenter validation is necessary.

Wider implications of the findings: Our study results indicated that KIDSCORE™D5 predicted clinical pregnancy and that morphokinetic parameters related to clinical pregnancy were similar between day–5 and day–6 blastocysts. Hence, morphokinetic evaluation can serve as a criterion for deciding which of multiple day–6 blastocysts can be transferred.

Trial registration number

Not applicable

Pairing Forces Govern Population of Doubly Magic ^{54}Ca from Direct Reactions

Direct proton-knockout reactions of ^{55}Sc at ∼220  MeV/nucleon were studied at the RIKEN Radioactive Isotope Beam Factory. Populated states of ^{54}Ca were investigated through γ-ray and invariant-mass spectroscopy. Level energies were calculated from the nuclear shell model employing a phenomenological internucleon interaction. Theoretical cross sections to states were calculated from distorted-wave impulse approximation estimates multiplied by the shell model spectroscopic factors, which describe the wave function overlap of the ^{55}Sc ground state with states in ^{54}Ca. Despite the calculations showing a significant amplitude of excited neutron configurations in the ground-state of ^{55}Sc, valence proton removals populated predominantly the ground state of ^{54}Ca. This counterintuitive result is attributed to pairing effects leading to a dominance of the ground-state spectroscopic factor. Owing to the ubiquity of the pairing interaction, this argument should be generally applicable to direct knockout reactions from odd-even to even-even nuclei.