Artifact reduction in low and ultra-low dose chest computed tomography for patients with pacemaker: A phantom study

INTRODUCTION

Implanted pacemakers (PM) would decrease the detection of lung nodules in chest computed tomography (CT) due to the metal artifact. This study aimed to explore the computer-aided diagnosis (CAD) detectability of pulmonary nodules for the patients implanted with PMs in low- and ultra-low-dose chest CT screening.

METHODS

Four different sizes of artificial nodules were placed in an anthropomorphic chest phantom with two alternative diameters utilized. A commercially available PM was placed on the surface of the left chest wall of the phantom. The image acquisitions were performed with 120 kV and 150 kV with a dedicated selective photon shield made of tin filter (Sn150 kV) at low- and ultra-low- radiation doses (1.0 and 0.5 mGy of volume CT dose index), and reconstructed with and without Iterative Metal Artifact Reduction (iMAR, Siemens Healthineers, Erlangen, Germany). The relative artifact index (AIr) was calculated as an index of metal artifacts, and the nodule detectability was evaluated with a CAD system.

RESULTS

Sn150 kV reduced AIr in all acquisitions when comparing 120 kV and Sn150 kV. Although PM reduced the detectability of nodules, Sn150 kV showed higher detectability compared to 120 kV. The use of iMAR showed inconsistent results in nodule detectability.

CONCLUSION

Sn150 kV reduced PM-induced metal artifacts and improved nodule detectability with CAD compared to 120 kV acquisition in many conditions including low and ultra-low doses and large phantoms, but iMAR did not improve the detectability.

IMPLICATIONS FOR PRACTICE

Based on the results of the current phantom study, low and ultra-low dose with Sn150 kV acquisition reduced PM-induced metal artifacts and improved nodule detectability.

Association between skin toxicity and efficacy of necitumumab in squamous non-small-cell lung cancer: a pooled analysis of two randomized clinical trials-SQUIRE and JFCM

BACKGROUND

Efficacy of necitumumab [recombinant human monoclonal antibody that blocks the ligand binding epidermal growth factor receptor (EGFR)] in patients with squamous (SQ) non-small-cell lung cancer (NSCLC) has been confirmed in two randomized clinical trials (SQUIRE and JFCM). This study evaluated the association between efficacy and initial skin toxicity with necitumumab treatment by analyzing pooled data from two clinical trials (SQUIRE and JFCM).

MATERIALS AND METHODS

Data of 635 patients with SQ-NSCLC (intent-to-treat population) treated with necitumumab plus gemcitabine and cisplatin (N + GC) were pooled from two clinical trials (SQUIRE and JFCM). The relationship between skin toxicities developed by the end of the second cycle and efficacy was evaluated. Efficacy endpoints included overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). Univariate and multivariate analyses were carried out for these endpoints.

RESULTS

OS and ORR were associated with skin toxicity, whereas PFS was not. Patients with grade ≥2 or grade 1 skin toxicity had significantly longer OS compared to patients without skin toxicity (grade 0) in the N + GC group [median = 15.0 (grade ≥2); 12.7 (grade 1); 9.4 (grade 0) months; hazard ratio (HR) = 0.51 (grade ≥2 to grade 0); 95% confidence interval (CI) 0.40-0.64, P < 0.001 and HR = 0.64 (grade 1 to grade 0); 95% CI 0.52-0.80, P < 0.001]. In multivariate analysis, OS was significantly associated with skin toxicity.

CONCLUSIONS

A significant association was found between necitumumab-induced skin toxicity and efficacy. These results are consistent with the previously reported association between other EGFR inhibitors-induced skin toxicity and efficacy.

Comparing Various Resin Luting Cement Systems in Different Etching Modes Through Bond Durability and Morphological Features

OBJECTIVES

This study aimed to investigate bond performance of various resin luting cement (RLC) systems on enamel and dentin in different etching modes and to compare the RLC-tooth interface morphology using scanning electron microscopy (SEM).

METHODS AND MATERIALS

The self-adhesive RLC systems used in combination with universal adhesives were as follows: Scotchbond Universal Adhesive Plus + RelyX Universal (3M Oral Care) and Clearfil Universal Bond Quick ER + SA Luting Multi (Kuraray Noritake Dental). These RLC systems were also used alone as self-adhesive RLC systems without universal adhesives (self-adhesive mode). The conventional RLC systems for comparison materials were as follows: BeautiBond Xtream + ResiCem EX (Shofu) and Tooth Primer + Panavia V5 (Kuraray Noritake Dental). Twelve specimens were prepared for each group to measure shear bond strength (SBS) in different etching modes. A stainless-steel rod was used as a substitute for indirect restorations. Bonded specimens were allocated to baseline (stored for 24 hours) and artificially aged (thermocycling [TC] for 10,000 cycles) groups. Representative treated tooth surfaces and RLC-tooth interfaces were observed using SEM.

RESULTS

Three-way analysis of variance (ANOVA) revealed that all the factors (etching mode, storage period, and RLC system) had a significant influence on the enamel SBS values (p<0.05). Enamel SBS was significantly higher in etch-&-rinse (ER) mode than in self-etch (SE) mode, regardless of RLC system or storage period. Three-way ANOVA showed that all the factors had a significant influence on the dentin SBS values (p<0.001). Most RLC systems showed significantly higher dentin SBS in SE mode than in ER mode, regardless of storage period. However, the combination with Scotchbond Universal Adhesive Plus and RelyX Universal showed no significant difference in SBS values between etching modes at the baseline and showed a significantly higher SBS value in ER mode than in SE mode after TC.

CONCLUSIONS

The self-adhesive RLC systems with universal adhesives tended to show higher enamel and dentin bond performance than the self-adhesive RLC systems alone. The morphology of treated tooth surfaces and resin cement-tooth interfaces were dependent on the RLC system and etching mode used. The RLC systems with primer application showed a thin, high-density layer above the intact dentin in both etching modes, suggesting chemical interaction.

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.

Roles of Sphingosine Kinase and Sphingosine-1-Phosphate Receptor 2 in Endotoxin-Induced Acute Retinal Inflammation

PURPOSE

To investigate the roles of sphingosine kinases (SphKs) and sphingosine-1-phosphate receptors (S1PRs) in endotoxin-induced uveitis (EIU) mice.

METHODS

EIU model was induced using an intraperitoneal injection of lipopolysaccharide (LPS). The expression of SphKs and S1PRs in the retina was assessed using quantitative polymerase chain reaction (qPCR) and immunofluorescence. The effects of S1PR antagonists on the expression of inflammatory cytokines in the retina were evaluated using qPCR and western blotting. Effects of leukocyte infiltration of the retinal vessels were evaluated to determine the effects of the S1PR2 antagonist and genetic deletion of S1PR2 on retinal inflammation.

RESULTS

Retinal SphK1 expression was significantly upregulated in EIU. SphK1 was expressed in the GCL, IPL, and OPL and S1PR2 was expressed in the GCL, INL, and OPL. Positive cells in IPL and OPL of EIU retina were identified as endothelial cells. S1PR2 antagonist and genetic deletion of S1PR2 significantly suppressed the expression of IL-1α, IL-6, TNF-α, and ICAM-1, whereas S1PR1/3 antagonist did not. Use of S1PR2 antagonist and S1PR2 knockout in mice significantly ameliorated leukocyte adhesion induced by LPS.

CONCLUSION

SphK1/S1P/S1PR2 signaling was upregulated in EIU and S1PR2 inhibition suppressed inflammatory response. Targeting this signaling pathway has potential for treating retinal inflammatory diseases.

Synergic effects of EP2 and FP receptors co-activation on Blood-Retinal Barrier and Microglia

Macular edema (ME) is caused with disruption of the blood-retinal barrier (BRB) followed by fluid accumulation in the subretinal space. Main components of the outer and inner BRB are retinal pigment epithelial (RPE) cells and retinal microvascular endothelial cells, respectively. In addition, glial cells also participate in the functional regulation of the BRB as the member of 'neurovascular unit'. Under various stresses, cells in neurovascular units secrete inflammatory cytokines. Neuroinflammation induced by these cytokines can cause BRB dysfunction by degrading barrier-related proteins and contribute to the pathophysiology of ME. Prostaglandins (PGs) are crucial lipid mediators involved in neuroinflammation. Among PGs, a novel EP2 agonist, omidenepag (OMD) acts on not only the uveoscleral pathway but also the conventional pathway, unlike F prostanoid (FP) receptor agonists. Moreover, the combination use of the EP and the FP agonist is not recommended because of the risk of inflammation. In this study, we investigated effects of OMD and latanoprost acid (LTA), a FP agonist, on BRB and microglia in vitro and in vivo. To investigate the function of outer/inner BRB and microglia, in vitro, ARPE-19 cells, human retinal microvascular endothelial cells (HRMECs), and MG5 cells were used. Cell viability, inflammatory cytokines mRNA and protein levels, barrier morphology/function, and microglial activation were evaluated using proliferation assays, qRT-PCR, ELISA, immunocytochemistry, trans-epithelial electrical resistance, and permeability assay. Moreover, after vitreous injection into the mouse, outer BRB morphology, glial activation, and cytokine expression were assessed. Each OMD and LTA alone did not affect the viability or cytokines expression of the three types of cells. In ARPE-19 cells, the co-stimulation of OMD and LTA increased the mRNA and protein levels of inflammatory cytokines (IL-6, TNF-α, and VEGF-A) and decreased the barrier function and the junction-related protein (ZO-1 and β-catenin). By contrast in HRMECs, the co-stimulation affected significant differences in the mRNA levels of some cytokine (IL-6 and TNF-α) but enhanced the barrier function. In MG5 cells, the cytokines mRNA and size of Iba1-expressed cell were increased. A non-steroidal anti-inflammatory inhibited the barrier dysfunction and the junction-related protein downregulation in ARPE-19 cells and activation of MG5 cells. Also in vivo, the co-stimulation induced outer BRB disruption, cytokine increase, and retinal glial activation. Therefore, the co-stimulation of EP2 and FP induced the inflammatory cytokine-mediated outer BRB disruption, the enhanced inner BRB function, and the microglial activation. The BRB imbalance and the intrinsic prostaglandin production may be involved in OMD-related inflammation.

Impact of the lateral skeletal stability following bilateral sagittal split ramus osteotomy for mandibular asymmetry

This study evaluated the stability of bilateral sagittal split ramus osteotomy (BSSRO) associated with positional plagiocephaly and temporal and masseter muscles using posteroanterior cephalogram analysis and three-dimensional computed tomography (3D-CT). This retrospective cohort study included 31 patients who underwent BSSRO for mandibular asymmetry. The cranial vault asymmetry index (CVAI) and the cephalic index were used as indicators of positional plagiocephaly. The distance from the vertical reference line to the menton (Me) was measured on posteroanterior cephalograms immediately and 1 year after surgery, and postoperative stability was assessed. Temporal and masseter muscles were constructed from 3D-CT data and their volumes were measured. Simple regression analysis showed a significant correlation between postoperative changes in the vertical reference line to the Me and the CVAI (R = 0.56, p = 0.001), the amount of surgical movement in the vertical reference line to the Me (R = 0.41, p = 0.023), and the variable temporal muscle volume (R = 0.27, p = 0.028). There was no significant correlation between postoperative changes in the vertical reference line to the Me and the cephalic index (R = 0.093, p = 0.62) and variable masseter muscle volume (R = 0.16, p = 0.38). According to multivariate analysis, CVAI (p = 0.003) and amount of surgical movement in the vertical reference line to the Me (p = 0.014) were significant predictors of postoperative change in the vertical reference line to the Me. Positional plagiocephaly and amount of surgical movement influence lateral skeletal stability following BSSRO for mandibular asymmetry.

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.

Dosimetric Evaluation of Targets and Organs at Risk in Dose Escalation Study for Total Marrow and Lymphoid Irradiation

PURPOSE/OBJECTIVE(S)

Total marrow and lymphoid irradiation (TMLI) delivers radiation dose to the bone marrow and lymph nodal region while reducing the dose to non-target organs. We conducted a dose-escalation study of TMLI to improve treatment outcomes while reducing OAR doses using intensity-modulated radiation therapy. However, this dose escalation strategy may cause increasing risk of recurrence and adverse events because of dose uniformity compromises of the target. We hypothesized that the homogeneity index (HI) could become worse with increased target's dose while maintaining reduced OAR doses for the nine patients enrolled in the TMLI phase Ⅰ clinical trial.

MATERIALS/METHODS

Nine patients treated with TMLI using a treatment delivery system from September 2019 to August 2021 were included. The prescribed doses were 14 Gy/6 fr, 16 Gy/6 fr, and 18 Gy/6 fr twice daily for 3 days, with three patients allocated each prescription. Bone marrow, lymph nodal region, spleen, testis, brain, and liver were designated as targets. The bone marrow was divided into eight parts (see Table); an individual PTV margin was added to each structure. We intended to deliver the D80% prescription dose for PTV. For the brain and liver, the prescribed dose was 12 Gy in consideration of function preservation. Lenses, oral cavity, parotid glands, lungs, heart, esophagus, stomach, kidneys, intestines, and breasts were defined as OAR. Targets were evaluated with HI that was calculated using the formula HI = (D2%-D98%)/D50%, based on ICRU report 83. For OARs, Dmax, D2%, D10%, and mean dose constraint were evaluated.

RESULTS

The table lists HI for the PTV_ALL and each target. The HI of PTV_ALL rose with increasing prescription dose and was highest at 18 Gy. The highest HI was 0.632 for PTV_Rib at 18 Gy, and the lowest HI was 0.045 for PTV_testis at 14 Gy. OAR Dose constraints were achieved in all patients. The average OAR doses in all cases for lenses, oral cavity, parotid glands, lungs, heart, esophagus, intestines, kidneys, and breast were 4.7±0.80, 4.4±0.51, 6.7±0.48, 7.6±0.22, 7.8±0.19, 6.7±0.18, 7.4±1.12, 6.9±0.96, and 14.7 Gy, respectively. The Dmax of the lenes, D2% of the esophagus, and D10% of the stomach were 7.2 ± 1.09, 11.5 ± 0.47, and 10.9 ± 0.98 Gy, respectively.

CONCLUSION

In the TMLI phase I clinical trial, we evaluated the dose uniformity to the targets and the OAR dose constraints. Although the HI for PTV_ALL worsened with increasing prescription dose, compliance with OAR dose constraints was achieved in all patients.

Artificial placenta technology: History, potential and perception

As presently conceptualised, the artificial placenta (AP) is an experimental life support platform for extremely preterm infants (i.e. 400-600 g; 21-23+6 weeks of gestation) born at the border of viability. It is based around the oxygenation of the periviable fetus using gas-exchangers connected to the fetal vasculature. In this system, the lung remains fluid-filled and the fetus remains in a quiescent state. The AP has been in development for some sixty years. Over this time, animal experimental models have evolved iteratively from employing external pump-driven systems used to support comparatively mature fetuses (generally goats or sheep) to platforms driven by the fetal heart and used successfully to maintain extremely premature fetuses weighing around 600 g. Simultaneously, sizable advances in neonatal and obstetric care mean that the nature of a potential candidate patient for this therapy, and thus the threshold success level for justifying its adoption, have both changed markedly since this approach was first conceived. Five landmark breakthroughs have occurred over the developmental history of the AP: i) the first human studies reported in the 1950's; ii) foundation animal studies reported in the 1960's; iii) the first extended use of AP technology combined with fetal pulmonary resuscitation reported in the 1990s; iv) the development of AP systems powered by the fetal heart reported in the 2000's; and v) the adaption of this technology to maintain extremely preterm fetuses (i.e. 500-600 g body weight) reported in the 2010's. Using this framework, the present paper will provide a review of the developmental history of this long-running experimental system and up-to-date assessment of the published field today. With the apparent acceleration of AP technology towards clinical application, there has been an increase in the attention paid to the field, along with some inaccurate commentary regarding its potential application and merits. Additionally, this paper will address several misrepresentations regarding the potential application of AP technology that serve to distract from the significant potential of this approach to greatly improve outcomes for extremely preterm infants born at or close to the present border of viability.

Downregulation of VEGF in the retinal pigment epithelium followed by choriocapillaris atrophy after NaIO3 treatment in mice

Sodium iodate (NaIO3) induces retinal pigment epithelium (RPE) dysfunction, which leads to photoreceptor degeneration. Previously, we used electron microscopy to show that the administration of NaIO3 resulted in the accumulation of cell debris in the subretinal space, which was thought to be caused by failed phagocytosis in the outer segment of the photoreceptor due to RPE dysfunction. We further analyzed the pathological changes in the retina and choroid of NaIO3-injected mice, and found that the expression of OTX2, an RPE marker, disappeared from central part of the RPE 1 day after NaIO3 administration. Furthermore, fenestrated capillaries (choriocapillaris, CC) adjacent to the RPE could not be identified only 2 days after NaIO3 administration. An examination of the expression of the CC-specific protein plasmalemma vesicle-associated protein (PLVAP), in sections and flat-mount retina/choroid specimens showed destruction of the CC, and complete disappearance of the PLVAP signal 7 days after NaIO3 administration. In contrast, CD31 flat-mount immunohistochemistry of the retina indicated no difference in retinal vessels between NaIO3-treated mice and controls. Electron microscopy showed that the fenestrated capillaries in the kidney and duodenum were morphologically indistinguishable between control and NaIO3-treated mice. We examined cytokine production in the retina and RPE, and found that the Vegfa transcript level in the RPE decreased starting 1 day after NaIO3 administration. Taken together, these observations show that NaIO3 reduces the CC in the early stages of the pathology, which is accompanied by a rapid decrease in Vegfa expression in the RPE.

A two-color dual-comb system for time-resolved measurements of ultrafast magnetization dynamics using triggerless asynchronous optical sampling

We report on an Er-doped fiber (EDF)-laser-based dual-comb system that allows us to perform triggerless asynchronous optical sampling pump-probe measurements of ultrafast demagnetization and spin precession in magnetic materials. Because the oscillation frequencies of the two frequency-comb light sources are highly stabilized, the pulse-to-pulse timing jitter is sufficiently suppressed, and data accumulation without any trigger signals is possible. To effectively induce spin precession in ferromagnetic thin films, the spectral bandwidth of the output of one of the EDF frequency comb sources is broadened by a highly nonlinear fiber and then amplified at a wavelength of about 1030 nm by a Yb-doped fiber amplifier. The output of the other frequency comb source is converted to about 775 nm by second harmonic generation. We used this system to observe ultrafast demagnetization and spin precession dynamics on the picosecond and nanosecond time scales in a permalloy thin film. This time-domain spectroscopy system is promising for the rapid characterization of spin-wave generation and propagation dynamics in magnetic materials.

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.

The histone H3K36 demethylase Fbxl11 plays pivotal roles in the development of retinal late-born cell types

Histone methylation plays a vital role in retinal development. However, the role of histone H3K36 methylation in retinal development is not clear. We examined the role of H3K36 methylation by loss-of-function analysis of H3K36me1/2 demethylases, Fbxl10, and Fbxl11. We analyzed the effect of knockout of these genes in the developing and mature retina on retinal development. Knockout of Fbxl10 specifically in the developing retina did not result in gross developmental abnormalities. Although adult rod photoreceptor-specific knockout of Fbxl11 in mature retinas did not result in morphological abnormalities, Fbxl11 knockout in developing retinas increased apoptosis, suppressed the proliferation of retinal progenitor cells, and resulted in microphthalmia. Morphological analysis revealed perturbed differentiation of rod photoreceptor and bipolar cells. RNA-seq of retinas at P7 showed markedly decreased expression of genes characterizing rod photoreceptor and bipolar cells in Fbxl11-knockout retinas. In addition, perturbation of alternative splicing increased intron retention in Fbxl11-knockout retinas. Genome-wide evaluation of the H3K36 methylation status revealed that Fbxl11 knockout altered the distribution of H3K36me2/3 in genes important for rod photoreceptor development. Taken together, we show that Fbxl11 plays pivotal roles in the development of retinal late-born cell types and may contribute to tight control of H3K36 methylation during retinal development.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Setd5, but not Setd2, is indispensable for retinal cell survival and proliferation

Trimethylation of histone H3 at lysine 36 (H3K36me3) is associated with active transcription. We used mouse retinal explant cultures and shRNA to investigate the roles of Setd2 and Setd5, which encode H3K36me3 methyltransferases, in retinal development. We found that shSetd5 caused abnormal retinal structures and reduced rods and Müller cells, whereas shSetd2 did not cause any abnormalities. The mutant SETD5 lacking the SET domain failed to reverse the phenotypes observed in the shSetd5-expressing retinas, while SETD5S1257*, which does not interact with HDAC3 and PAF1 complexes, rescued proliferation, but not apoptosis, induced by shSetd5. Taken together, we found that Setd5, but not Setd2, is essential for sustaining retinal cell survival and proliferation, and the SET domain of SETD5 is pivotal for both functions.

Evaluation of CRISPR/Cas9 exon-skipping vector for choroideremia using human induced pluripotent stem cell-derived RPE

BACKGROUND

Exon-skipping is a powerful genetic tool, especially when delivering genes using an AAV-mediated full-length gene supplementation strategy is difficult owing to large length of genes. Here, we used engineered human induced pluripotent stem cells and artificial intelligence to evaluate clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated protein 9-based exon-skipping vectors targeting genes of the retinal pigment epithelium (RPE). The model system was choroideremia; this is an X-linked inherited retinal disease caused by mutation of the CHM gene.

METHODS

We explored whether artificial intelligence detected differentiation of human OTX2, PAX6 and MITF (hOPM) cells, in which OTX2, PAX6 and MITF expression was induced by doxycycline treatment, into RPE. Plasmid encoding CHM exon-skipping modules targeting the splice donor sites of exons 6 were constructed. A clonal hOPM cell line with a frameshift mutation in exon 6 was generated and differentiated into RPE. CHM exon 6-skipping was induced, and the effects of skipping on phagocytic activity, cell death and prenylation of Rab small GTPase (RAB) were evaluated using flow cytometry, an in vitro prenylation assay and western blotting.

RESULTS

Artificial intelligence-based evaluation of RPE differentiation was successful. Retinal pigment epithelium cells with a frameshift mutation in exon 6 showed increased cell death, reduced phagocytic activity and increased cytosolic unprenylated RABs only when oxidative stress was in play. The latter two phenotypes were partially rescued by exon 6-skipping of CHM.

CONCLUSIONS

CHM exon 6-skipping contributed to RPE phagocytosis probably by increasing RAB38 prenylation under oxidative stress.

Translocation of nuclear chromatin distribution to the periphery reflects dephosphorylated threonine-821/826 of the retinoblastoma protein (pRb) in T24 cells treated with Bacillus Calmette-Guérin

The standard treatment for non-muscle-invasive bladder cancer is intravesical Bacillus Calmette-Guérin (BCG) therapy, which is considered the only intravesical therapy that reduces the risk of progression to muscle-invasive cancer. BCG unresponsiveness, in which intravesical BCG therapy is ineffective, has become a problem. It is thus important to evaluate the effectiveness of BCG treatment for patients as soon as possible in order to identify the optimal therapy. Urine cytology is a noninvasive, easy, and cost-effective method that has been used during BCG treatment, but primarily only to determine benign or malignant status; findings concerning the efficacy of BCG treatment based on urine cytology have not been reported. We investigated the relationship between BCG exposure and nuclear an important criterion in urine cytology, i.e., nuclear chromatin patterns. We used three types of cultured cells to evaluate nuclear chromatin patterns and the cell cycle, and we used T24 cells to evaluate the phosphorylation of retinoblastoma protein (pRb) in six-times of BCG exposures. The results revealed that after the second BCG exposure, (i) nuclear chromatin is distributed predominantly at the nuclear periphery and (ii) the dephosphorylation of threonine-821/826 in pRb occurs. This is the first report of a dynamic change in the nuclear chromatin pattern induced by exposure to BCG. Molecular findings also suggested a relationship between this phenomenon and cell-cycle proteins. Although these results are preliminary, they contribute to our understanding of the cytomorphological changes that occur with BCG exposure.

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}.

The effect of Daikenchuto on blood flow of the superior mesenteric artery and portal vein in ELBW: A prospective study

BACKGROUND

Focal intestinal perforation (FIP) is a devastating complication of premature birth, and extremely low birth weight (ELBW) infants are at highest risk. This study aimed to evaluate the relationship of the superior mesenteric artery (SMA) and portal vein (PV) blood flow velocities to investigate the association between intestinal blood flow and FIP. In addition, the herbal formula Daikenchuto (TJ-100) is expected to improve intestinal blood flow disorders; therefore, we evaluated its effect.

METHODS

We conducted a prospective cohort study of 15 ELBW infants from January 2020 to August 2021. Measured variables included birth weight, 5-minute Apgar score, time of oral feeding initiation, ductus arteriosus (PDA) closure (percent), diastolic and systolic blood pressure, SMA and PV blood flow velocity, and FIP onset data. Fifteen infants were divided into three groups: a non-surgery group (Group I; 6), a surgery group with FIP (Group II; 4), and a TJ-100 administration group (Group III; 5). The main outcome parameters included SMA and PV blood flow velocities with TJ-100.

RESULTS

SMA and PV blood flow differed significantly for the SMA of Group I and the SMA and PV of Group III (P < 0.01, P = 0.01, and P = 0.04, respectively). There was a correlation between SMA and PV in Group III (P = 0.03).

CONCLUSION

TJ-100 may increase SMA and PV blood flow and improve intestinal blood flow in ELBW infants at risk of FIP. Therefore, the effects of TJ-100 should undergo further study.

Loss-of-function approach using mouse retinal explants showed pivotal roles of Nmnat2 in early and middle stages of retinal development

Nicotinamide mononucleotide adenylyltransferase (Nmnat) is a class of enzymes with three members (Nmnat1-3). Nmnat1 is in nucleus and associated with Leber congenital amaurosis, a form of early-onset retinal degeneration, while Nmnat2 is in cytoplasm and a well-characterized neuroprotective factor. The differences in their biological roles in the retina are unclear. We performed short hairpin RNA (shRNA)-based loss-of-function analysis of Nmnat2 during mouse retinal development in retinal explant cultures prepared from early (E14.5), middle (E17.5), or late (postnatal day [P]0.5) developmental stages. Nmnat2 has important roles in the survival of retinal cells in the early and middle stages of retinal development. Retinal cell death caused by Nmnat2 knockdown could be partially rescued by supplementation with NAD or nicotinamide mononucleotide (NMN). Survival of retinal cells in the late stage of retinal development was unaffected by Nmnat2, but differentiation of Müller glia was controlled by Nmnat2. RNA-Seq analyses showed perturbation of gene expression patterns by shRNAs specific for Nmnat1 or Nmnat2, but gene ontology analysis did not provide a rational explanation for the phenotype. This study showed that Nmnat2 has multiple developmental stage-dependent roles during mouse retinal development, which were clearly different from those of Nmnat1, suggesting specific roles for Nmnat1 and Nmnat2.

P-131 The fate of irregularly divided blastomeres: why does “Direct cleavage” reduce blastocyst development rate but not blastocyst euploid rate?

Study question

How do the blastomeres formed by direct cleavage (dynamics of one cell dividing into three or more cells) subsequently develop?

Summary answer

About half of the blastomeres by direct cleavage did not form blastocysts.

What is known already

There are many reports that embryos with direct cleavage in the early development have a lower blastocyst development rate because direct cleavage produces chromosomal abnormal cells. However, when such embryos develop into blastocysts, there have been some reports that the transfer pregnancy rate and euploid rate did not decrease, but the reasons for this have not been clarified.

Study design, size, duration

This is a retrospective study of 89 blastocysts obtained during 2013-18. These embryos were those that patients requested to be discarded and consented to be used in this study. All target embryos were time-lapse monitored by EmbryoScope (Vitrolife, Sweden), and several trophectoderms were biopsied and examined for euploidy.

Participants/materials, setting, methods

The target embryos were classified into three groups: embryos with normal first and second cleavage (NC group), embryos with irregular division (one cell dividing into three or more cells) called direct cleavage at the first cleavage (DC1 group), and embryos with direct cleavage of one blastomere at the second cleavage (DC2 group). It was recorded whether the blastomeres of the embryos subsequently developed into blastocysts or not. NGS analysis was performed on the embryos.

Main results and the role of chance

The target embryos were classified as 48 in the NC group, 32 in the DC1 group, and 9 in the DC2 group. Whether the blastomeres in the target embryos subsequently formed blastocysts or not was recorded one by one by time-lapse images, resulting in the blastomeres’ blastocyst formation rate was 95.1% in the NC group and 55.9% in the DC1 group, which was significantly lower in the DC1 group (P &lt; 0.01). In the DC2 group, blastomeres formed by normal division and those by direct cleavage at the second cleavage were recorded separately, and the blastocyst formation rate was 90.8% for normal cleavage blastomeres and 46.0% for direct cleavage blastomeres, with significantly lower rates for direct cleavage blastomeres (P &lt; 0.01). Therefore, about half of the blastomeres generated by direct cleavage at the first or second cleavage did not form blastocysts. The results of NGS analysis were as follows: NC group: 35.4% euploid, 45.8% aneuploid, and 18.8% mosaic; DC1 group: 37.5%, 53.1%, and 9.4%, respectively; and DC2 group: 55.6%, 33.3%, and 11.1%, respectively. There was no significant difference in any of the items, suggesting that direct cleavage does not affect the euploidy of blastocysts.

Limitations, reasons for caution

For the purpose of NGS analysis, all the target embryos in this study were blastocysts, but if all the cultured embryos were included, arrested embryos would be included, which would probably result in more blastomeres formed by direct cleavage not developing into blastocysts.

Wider implications of the findings

The blastomeres generated by direct cleavage were often excluded from blastocyst formation. This may be an exclusion of chromosomally abnormal cells and may be one of the reasons why direct cleavage decreases blastocyst development rate but does not decrease blastocyst euploid rate.

Trial registration number

not applicable

O-289 Effects of Taxol on the developmental potency of human and mouse GV oocytes

Study question

Is it possible to improve the quality of oocytes with delayed maturation or aging?

Summary answer

Yes, modification of oocyte microtubules at the germinal vesicle (GV) stage inhibits abnormal chromosome separation in in-vitro maturation and enhances early cleavage.

What is known already

Oocyte aging is characterized by an increase of aneuploidy and a decrease of the developmental potency with maternal ages, which will results in low frequencies of the blastocyte formation and implantation. In addition to the 1st meiotic division, it has become clear that the 2nd meiotic division also significantly contributes to aneuploidy production which is followed by pre-implantation embryo loss. However, no method for overcoming the oocyte aging has been established.

Study design, size, duration

Human GV oocytes with delayed maturation obtained from consented female patients were used. Mouse GV oocytes collected from 9-15 month old ICR mice were also used. After exposure to Taxol for 1hr, the oocytes were matured in vitro and examined cytogenetically and cytologically at the GV stage, the MII stage and pronuclear stage.

Participants/materials, setting, methods

RNA transcripts of the GV stage oocytes were compared before and after Taxol exposure with microarray in both species. Chromosome aberrations at the MII stage and blastocyst formation rate were examined in human IVM oocytes. Mouse IVM oocytes were evaluated on 2nd polar body (PB) extrusion and O2 consumption (CRAS3.0, Crino Co Inc.) at the pronuclear stage after parthenogenetic activation with electro-stimulation.

Main results and the role of chance

After Taxol treatment, premature chromosome separation was significantly reduced from 96% to 7% and the blastocyst formation rate increased from 3% to 16% in human. In mice, normal PB extrusion rate increased from 29% to 92%, and oxygen consumption was higher in some pronuclear oocytes. In human GV oocytes, taxol treatment altered gene expression only in a few factors related to chromosome attachment and segregation. On the other hand, in mouse GV oocytes, gene expression was significantly altered by oocyte aging and Taxol treatment.

Limitations, reasons for caution

The present results were obtained in human GV oocytes with delayed maturation which were collected after PMS and HCG administrations. It is not clear whether Taxol is effective on the GV oocytes collected before HCG administration.

Wider implications of the findings

Our results indicate that the combination of biochemical modification and IVM in the GV stage may be able to restore the aging of human oocytes.

Trial registration number

not applicable

Lysophosphatidylcholine acyltransferase 1 controls mitochondrial reactive oxygen species generation and survival of retinal photoreceptor cells

Due to their high energy demands and characteristic morphology, retinal photoreceptor cells require a specialized lipid metabolism for survival and function. Accordingly, dysregulation of lipid metabolism leads to the photoreceptor cell death and retinal degeneration. Mice bearing a frameshift mutation in the gene encoding lysophosphatidylcholine acyltransferase 1 (Lpcat1), which produces saturated phosphatidylcholine (PC) composed of two saturated fatty acids, has been reported to cause spontaneous retinal degeneration in mice; however, the mechanism by which this mutation affects degeneration is unclear. In this study, we performed a detailed characterization of LPCAT1 in the retina and found that genetic deletion of Lpcat1 induces light-independent and photoreceptor-specific apoptosis in mice. Lipidomic analyses of the retina and isolated photoreceptor outer segment (OS) suggested that loss of Lpcat1 not only decreased saturated PC production but also affected membrane lipid composition, presumably by altering saturated fatty acyl-CoA availability. Furthermore, we demonstrated that Lpcat1 deletion led to increased mitochondrial reactive oxygen species levels in photoreceptor cells, but not in other retinal cells, and did not affect the OS structure or trafficking of OS-localized proteins. These results suggest that the LPCAT1-dependent production of saturated PC plays critical roles in photoreceptor maturation. Our findings highlight the therapeutic potential of saturated fatty acid metabolism in photoreceptor cell degeneration-related retinal diseases.

Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

Stratification of prostate cancer patients into low- and high-grade groups using multiparametric magnetic resonance radiomics with dynamic contrast-enhanced image joint histograms

PURPOSE

This study aimed to investigate the potential of stratification of prostate cancer patients into low- and high-grade groups (GGs) using multiparametric magnetic resonance (mpMR) radiomics in conjunction with two-dimensional (2D) joint histograms computed with dynamic contrast-enhanced (DCE) images.

METHODS

A total of 101 prostate cancer regions extracted from the MR images of 44 patients were identified and divided into training (n = 31 with 72 cancer regions) and test datasets (n = 13 with 29 cancer regions). Each dataset included low-grade tumors (International Society of Urological Pathology [ISUP] GG ≤ 2) and high-grade tumors (ISUP GG ≥ 3). A total of 137,970 features consisted of mpMR image (16 types of images in four sequences)-based and joint histogram (DCE images at 10 phases)-based features for each cancer region. Joint histogram features can visualize temporally changing perfusion patterns in prostate cancer based on the joint histograms between different phases or subtraction phases of DCE images. Nine signatures (a set of significant features related to GGs) were determined using the best combinations of features selected using the least absolute shrinkage and selection operator. Further, support vector machine models with the nine signatures were built based on a leave-one-out cross-validation for the training dataset and evaluated with receiver operating characteristic (ROC) curve analysis.

RESULTS

The signature showing the best performance was constructed using six features derived from the joint histograms, DCE original images, and apparent diffusion coefficient maps. The areas under the ROC curves for the training and test datasets were 1.00 and 0.985, respectively.

CONCLUSION

This study suggests that the proposed approach with mpMR radiomics in conjunction with 2D joint histogram computed with DCE images could have the potential to stratify prostate cancer patients into low- and high-GGs.

Effect of Lecithin-Bound Iodine Treatment on Inherited Retinal Degeneration in Mice

Purpose

Although lecithin-bound iodine (LBI) has been administered orally for retinal diseases, a lack of clinical studies and obscure action mechanism of LBI hinder its large-scale prescription. LBI treatment suppresses chemokine (C-C motif) ligand 2 (CCL2) secretion from retinal pigment epithelial cells in vitro. Herein, we assessed the in vivo effect of LBI treatment on retinal degeneration (RD) in mice.

Methods

Mertk^−/−Cx3cr1^GFP/+Ccr2^RFP/+ mice—a model for RD—demonstrate fluorescein-labeled microglia/macrophage to facilitate visualization of CX3CR1-green fluorescent protein (GFP) and CCR2-red fluorescent protein (RFP). An LBI-containing mouse diet was provided to Mertk^−/−Cx3cr1^GFP/+Ccr2^RFP/+ mice ad libitum from postnatal day (POD) 28. CX3CR1-GFP and CCR2-RFP expression was assessed at POD 56 using retinal sectioning and flat mounting. RD severity was assessed at POD 84. Retinal RNA was extracted from the mice of each group to measure chemokine expression. Electroretinography was performed to assess retinal function.

Results

CCR2-RFP expression in the retina and retinal pigment epithelial cells was suppressed by LBI treatment compared with that in the control at POD 56. The number of outer nuclear layer nuclei was higher in the group fed with LBI-containing diet than in the control mice at POD 84. Ccl2 and Ccr2 RNA expression was suppressed by LBI intake. Electroretinography showed the LBI-treated group to have a high b-wave amplitude compared with the control group.

Conclusions

Suppressing CCR2-RFP–positive macrophage invasion into the retina and CCL2 and CCR2 expression is a potential mechanism underlying LBI-mediated attenuation of RD.

Translational Relevance

Life-long LBI administration may become a candidate for treating RD.

Cutaneous ischemia-reperfusion injury is exacerbated by IL-36 receptor antagonist deficiency

BACKGROUND

Loss-of-function homozygous or compound heterozygous mutations in IL36RN, which encodes interleukin-36 receptor antagonist (IL-36Ra), has been implicated in the pathogenesis of skin disorders. However, the pathogenic role of IL-36Ra in cutaneous ischemia-reperfusion (I/R) injury remains unclear.

OBJECTIVES

We investigated the role of IL36Ra in cutaneous I/R injury.

METHODS

We examined I/R injury in Il36rn^-/- mice. The area of wounds, numbers of infiltrated cells, apoptotic cells and neutrophil extracellular trap (NET) formation were assessed. The expression levels of various genes were analysed using real-time RT-PCR. The expression of high mobility group box 1 (HMGB1), an endogenous toll-like receptor (TLR) 4 ligand, was confirmed using immunohistology, and serum HMGB1 levels were measured by ELISA. Cytokine production by stimulated cultured J774A.1 and HaCaT cells was examined.

RESULTS

IL-36Ra deficiency resulted in significantly delayed wound healing and increased neutrophil and macrophage infiltration into the wound tissues. Il36rn^-/- mice had increased mRNA expression levels of CXCL1, CXCL2, CCL4, TNF-α, TGF-β, IL-1β, IL-6 and IL-36γ relative to wild-type mice. Apoptosis was identified in keratinocytes by TUNEL assay. HMGB1 expression in the I/R site was decreased in both keratinocytes and adnexal cells, while serum HMGB1 levels were significantly elevated after reperfusion. The mRNA levels of various cytokines, including IL-1β, were elevated in J774A.1 cells through TLR4 signalling by HMGB1 stimulation. In addition, HaCaT cells stimulated with IL-1β showed significantly increased CXCL1, TNF-α, IL-6, IL-36β and IL-36γ mRNA expression. Furthermore, NET formation was increased by IL-36Ra deficiency. Finally, either the blockade of TLR4 signalling by TAK-242 or inhibition of NET formation by Cl-amidine normalized exacerbated I/R injury in Il36rn^-/- mice.

CONCLUSIONS

This study indicated that IL-36Ra deficiency exacerbates cutaneous I/R injury due to excessive inflammatory cell recruitment, NET formation, and excessive cytokine and chemokine production via the TLR4 pathway by HMGB1 released from epidermal apoptotic cells.

Low serum chloride level gives renin-angiotensin system inhibitor a prognostic impact in heart failure patients with preserved ejection fraction

Background

Hypochloremia is associated with a poor prognosis of heart failure (HF) patients. This phenomenon is sustained even in HF with preserved ejection fraction (HFpEF). Serum chloride level is known to be affected by serum renin secretion; however, this relationship is one of the least investigated field in HF patients. Renin-angiotensin system (RAS) inhibitor is recommended as a first-line medication for HF patients with reduced left ventricular ejection fraction, but no prior studies of RAS inhibitors have achieved to improve the prognosis of HFpEF patients.

Purpose

We investigated the relationship between baseline serum chloride level and the prognostic impact of RAS inhibitor in HFpEF patients.

Methods

This is an observational study including 1,913 consecutive patients who admitted to hospital due to worsening of HF and discharged alive in a single university hospital. After excluding patients who received regular hemodialysis and whose left ventricular ejection fraction were under 50%, 506 HFpEF patients were ultimately analyzed. They were categorized into tertiles by serum chloride levels at discharge (T1: −100 mEq/L, T2: 101–104 mEq/L, T3: 105- mEq/L), and patients in each category were further divided into subgroups depending on the prescription of RAS inhibitor at discharge (RAS inhibitor group and Non-RAS inhibitor group). The primary endpoint of this study was death from any cause.

Results

During the observation period with 479 days of median follow-up, 77 (15.2%) died. Patients in the RAS inhibitor group had significantly better prognosis than those in the Non-RAS inhibitor group in T1 category (Log-rank: p=0.003, Figure). In contrast, there was no statistical difference in the mortality between the RAS inhibitor group and Non-RAS inhibitor group in T2 and T3 categories (Log-rank: p=0.15, p=0.81, respectively, Figure). Multivariate Cox regression analysis in T1 category revealed that taking RAS inhibitor at discharge was independently associated with a lower mortality rate, even after the adjustment of diverse covariates (hazard ratio: 0.40, 95% confidence interval: 0.20–0.80).

Conclusion

In this observational study, the administration of RAS inhibitor was associated with an improved prognosis of HFpEF patients only in low serum chloride level at discharge. Therapeutic strategy focusing on the chloride level may be one of the promising options to find the light on a unintervenable prognosis of HFpEF.

Funding Acknowledgement

Type of funding sources: None.

Impact of catheter ablation on functional tricuspid regurgitation in patients with atrial fibrillation

Background

Since atrial functional tricuspid regurgitation (AF-TR) is associated with increased heart failure and mortality, the management of AF-TR is clinically important. Atrial fibrillation (AF) plays the main role in AF-TR. However, the effectiveness of catheter ablation (CA) and mechanism of improvement of AF-TR haven't been fully evaluated.

Purpose

We sought to investigate the impact of CA for AF on AF-TR in patients with moderate or more TR.

Methods

We retrospectively investigated consecutive 2685 patients with AF who received CA from February 2004 to December 2019 in Japan. The current study population consisted of 102 patients with moderate or greater TR who underwent CA for AF. The echocardiographic parameters were compared between pre-ablation and post-ablation transthoracic echocardiography (TTE), and the recurrence rate of AF/ atrial tachycardia (AT) was measured.

Results

The mean age was 73.2 years, 53% were women. TR severity and TR jet area significantly improved after CA for AF (TR jet area: 5.8 [3.9–7.6] cm2 to 2.0 [1.1–3.0] cm2, p&lt;0.001). In addition, mitral regurgitation (MR) jet area, left atrial (LA) area, mitral valve diameter, right ventricular (RV) end-diastolic area, right atrial (RA) area, tricuspid valve (TV) diameter decreased after CA (p&lt;0.001, &lt;0.001, &lt;0.001, = 0.02, &lt;0.001, and &lt;0.001, respectively). There was no significant difference between one-year recurrence of AF/AT and TR severity at pre-ablation TTE (moderate 28.6%, moderate to severe 37.2%, and severe 31.6%, p=0.72).

Conclusions

TR severity and jet area improved after CA in patients with AF and moderate or more TR. RV size, RA size, TV diameter also decreased after CA, which may be associated with TR improvement. There was no significant difference between one-year recurrence of AF/AT and TR severity at pre-ablation TTE.

Funding Acknowledgement

Type of funding sources: None.

Prognostic advantage of optimal medical therapy is not cancelled in hospitalized heart failure patients receiving regular hemodialysis

Background

As the first-line medications, renin-angiotensin-aldosterone system inhibitor (RAASi) and β-blocker provide prognostic benefits in patients with heart failure (HF) and reduced left ventricular ejection fraction (LVEF). However, the negative inotropic effect of these drugs may destabilize the hemodynamics during hemodialysis (HD) and become prognostically controversial in patients receiving regular HD. Indeed, prior studies have reported the cancellation of the favorable prognostic effects of RAASi and β-blocker in patients with HD. However, it is totally unknown whether the guideline-directed medical therapy affects the prognosis in HF patients receiving regular HD.

Purpose

We aimed to evaluate the prognostic impact of RAASi and β-blocker on the cardiovascular (CV) events in HF patients on regular HD.

Methods

This observational study initially included 1,930 consecutive patients who were hospitalized due to HF and discharged alive. Of these, 151 patients who received regular HD were ultimately analyzed. They were classified into 3 groups depending on the prescribing medications at discharge; patients who received none of RAASi or β-blocker (None group: N=19), either RAASi or β-blocker (Either group: N=56), and both RAASi and β-blocker (Both group: N=76). The primary endpoint was a composite of CV death and readmission due to HF.

Results

During the observation period of median 501 (interquartile range: 197–954) days, the primary endpoint occurred in 61 patients (40%). Kaplan-Meier analysis showed the highest rate of composite endpoint in the None group (log-rank for trend: p&lt;0.001, Figure). After adjusting for covariates of age, sex, LVEF, and systolic blood pressure and heart rate at discharge, the hazard ratio (HR) for a composite endpoint was significantly lower in the Either group or Both group than that in the None group [HR: 0.19, 95% confidence interval (CI): 0.08–0.45; HR: 0.16, 95% CI: 0.06–0.42, respectively].

Conclusions

The prescription of RAASi or β-blocker at discharge was associated with lower adverse CV event rates in patients on regular HD who were hospitalized for HF. In order to improve long-term prognosis of HF patients on HD, we should consider the prescription of RAASi or β-blocker for them if hemodynamics during HD is affordable.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Heart failure re-hospitalization differently affects the following mortality in patients with reduced, mid-range and preserved LVEF

Introduction

The recent advances in the treatment for heart failure with reduced ejection fraction (HFrEF) have been remarkable, while no therapy has convincingly improved the prognosis in HF patients with preserved (HFpEF) and mid-range (HFmrEF) ejection fraction. Frequent decompensations of HF lead to progressive deterioration of cardiac and renal function, and quality of life. Hence, prior studies have reported that the mortality of HFrEF patients increases as hospitalization for HF repeats. However, it is still unclear whether this trend applies for HFpEF and HFmrEF patients.

Purpose

We aimed to compare the prognostic impact of re-hospitalization due to HF on cardiovascular death (CVD) among HFrEF, HFmrEF and HFpEF patients.

Methods

This observational study included 1,930 consecutive patients who were hospitalized for worsening of HF and discharged alive. Of them, patients who have never or have not been hospitalized for HF at least last 2 years, were finally analyzed. Patients were consisted of the population with HFrEF (EF&lt;40%, n=421), HFmrEF (EF 40–49%, n=202) and HFpEF (EF&gt;50%, n=291). Patients in each EF-classified population were divide into 2 subgroups based on whether patients were re-hospitalized for HF during the observational period, respectively. The primary endpoint of this study was CVD.

Results

During the observation period, Kaplan-Meier analysis showed that patients who were re-hospitalized for HF had higher event rate of CVD in HFrEF group (Log-rank p=0.008, Figure). Even after adjusting with multivariate covariates including age, sex, EF, brain natriuretic peptide and estimated glomerular filtration rate, re-hospitalization for HF was an independent predictor for CVD in HFrEF group (HR: 1.95, 95% CI: 1.11–2.86, p=0.029). However, in HFmrEF group and HFpEF group, there was no significant difference in the rates of CVD between 2 subgroups divided whether patients were re-hospitalized for HF or not (p=0.91, p=0.34, respectively).

Conclusion

Re-hospitalization for HF affected the CVD rate in HFrEF group, but not in HFmrEF and HFpEF groups. The prevention of re-hospitalization for HF is important particularly in HFrEF patients in order to improve cardiovascular mortality.

Funding Acknowledgement

Type of funding sources: None.

Influence of renal dysfunction on clinical outcomes in elderly patients with atrial fibrillation: a subanalysis of the phase 3, randomized, placebo-controlled ELDERCARE-AF trial

Background

Renal dysfunction is common in elderly patients with atrial fibrillation (AF) and is thought to be associated with increased risk of thromboembolic and bleeding events. Once-daily low-dose (15 mg) edoxaban was superior to placebo in preventing stroke or systemic embolic events (S/SEE) without significantly increasing major bleeding events in very elderly (≥80 years) non-valvular AF (NVAF) patients in whom standard oral anticoagulant therapy at approved doses was inappropriate (ELDERCARE-AF trial). Little is known about how renal dysfunction affects the effects of low-dose edoxaban in these patients.

Purpose

We used prespecified subgroup analysis to investigate the relation between renal function (assessed by creatinine clearance, CrCl) and the efficacy and safety of edoxaban in elderly NVAF patients.

Methods

ELDERCARE-AF patients were divided into 3 subgroups according to baseline CrCl: normal renal function/mild dysfunction (CrCl &gt;50 mL/min), moderate renal dysfunction (CrCl ≥30 to ≤50 [“30–50”] mL/min) and severe renal dysfunction (CrCl ≥15 to &lt;30 [“15–30”] mL/min). Primary efficacy and safety endpoints were annualized incidence of S/SEE and ISTH-defined major bleeding, respectively.

Results

Of 984 patients randomized to edoxaban 15 mg or placebo (each group N=492), 681 completed the trial. The 303 discontinuations were due to withdrawal of consent (n=158), death (n=135), or other causes (n=10). Discontinuation rate was the same in the edoxaban and placebo groups. S/SEE incidence in patients with CrCl &gt;50, 30–50 and 15–30 mL/min was 2.0%, 1.3% and 3.5%, respectively, in edoxaban, and 4.4%, 4.6% and 9.7%, respectively, in placebo. In those with CrCl 30–50 and 15–30 mL/min, it was significantly lower in edoxaban than in placebo (adjusted hazard ratio [HR], 0.30 [95% CI, 0.10–0.91], p=0.03; and 0.33 [95% CI, 0.16–0.71], p&lt;0.01, respectively). Incidence of major bleeding in patients with CrCl &gt;50, 30–50 and 15–30 mL/min was 1.0%, 1.8% and 6.2%, respectively, in edoxaban, and 0.9%, 1.5% and 2.4%, respectively, in placebo. Incidence of major bleeding in those with CrCl 15–30 mL/min was higher in edoxaban but not significantly (adjusted HR, 2.53 [95% CI, 0.96–6.72], p=0.062). Incidence of gastrointestinal bleeding in patients with CrCl 15–30 mL/min was 4.3% in edoxaban and 1.6% in placebo (adjusted HR, 2.61 [95% CI, 0.79–8.68], p=0.12). Incidence of all-cause death in patients with CrCl &gt;50, 30–50 and 15–30 mL/min was 5.8%, 6.8% and 15.2%, respectively, in edoxaban, and 7.0%, 6.3% and 15.5%, respectively, in placebo (no significant intergroup differences).

Conclusions

Incidence of S/SEE, major bleeding and all-cause death increased with declining renal function in elderly NVAF patients. Edoxaban 15 mg remained superior to placebo in preventing S/SEE, even in those with moderate to severe renal dysfunction. Incidence of major bleeding in patients with severe renal dysfunction was higher (non-significantly) with edoxaban than with placebo.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Daiichi-Sankyo Co., Ltd.

P–131 Significance of the phenomenon of blastomere exclusion from compaction: Its relation to irregular cleavage, blastocyst development rate, and pregnancy rate

Study question

When does blastomere exclusion from compaction increase and what effect does it have on the embryo?

Summary answer

More blastomere were excluded from compaction in embryos with irregular cleavage, resulting in lower blastocyst development rates, but no decrease in pregnancy rates at transfer.

What is known already

It has been reported that many of the chromosome analysis results of blastomere excluded from compaction were aneuploid, and pointed out that this exclusion may be related to the repair of blastocyst euploidy, but the effect of the number of excluded blastomere has not been reported.

Study design, size, duration

This is a retrospective study of 578 embryos that developed into morula with time-lapse monitoring by EmbryoScope (Vitrolife) in 2018–2019.

Participants/materials, setting, methods

The target embryos were classified into two groups: embryos with normal first and second cleavage (normal cleavage group) and embryos with irregular cleavage (dynamics of one cell dividing into three or more cells), called “direct cleavage”, at either cleavage (DC group), and the number of blastomere excluded from compaction during morula formation was recorded and compared. The blastocyst development rate and single blastocyst transfer pregnancy rates of the two groups were compared.

Main results and the role of chance

There are 286 in the normal cleavage group and 292 in the DC group. The mean number of excluded blastomere was 0.76 and 3.55, respectively, which was significantly higher in the DC group (P &lt; 0.01). Good blastocyst (Gardner classification 4 or higher) development rate was 84.5% (239/283) and 65.8% (181/275), respectively, and high grade blastocyst (Gardner classification BB or higher) development rate was 43.9% (105/239) and 14.9% (27/181) of them, both significantly higher in the normal cleavage group (P &lt; 0.01). The single blastocyst transfer pregnancy rates were 31.6% (25/79) and 32.4% (11/34), and the miscarriage rates were 24.0% (6/25) and 27.3% (3/11), respectively, neither was there a significant difference between the two groups. So, direct cleavage increased the number of blastomere excluded from compaction, decreased the rate of morula to good blastocyst development and reduced blastocyst grade, but did not affect blastocyst transfer pregnancy rate and miscarriage rate.

Limitations, reasons for caution

Please note that all target embryos must have developed into morula or larger (embryos that did not develop into morula will not be included in the study).

Wider implications of the findings: Severe chromosomal aberrant blastomeres formed by direct cleavage were excluded from compaction, and the blastocyst development rate decreased due to a decrease in the amount of viable cells, but it is suggested that this blastomere exclusion mechanism is not related to euploidy after blastocyst development.

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.

Neuroprotective role of sphingolipid rheostat in excitotoxic retinal ganglion cell death

The glutamate excitotoxicity has been suggested as a factor involved in the loss of retinal neuronal cells, including retinal ganglion cell (RGC), in various retinal degenerative diseases including ischemia-reperfusion injury, diabetic retinopathy, and glaucoma. Excitotoxic RGC death is caused not only by direct damage to RGCs but also by indirect damage due to the inflammation of retinal glial cells. Sphingosine 1-phosphate (S1P) and ceramides are bioactive sphingolipids which have been shown to possess important physiological roles in cellular survival and apoptosis, and the balance between S1P and ceramide, sphingolipid rheostat, has been suggested to be important for determining cellular fate. Therefore, we conducted the present study to clarify the neuroprotective role of sphingolipid rheostat in excitotoxic RGC death in vivo and in vitro. Acute RGC death was induced by intravitreal N-methyl-d-aspartate (NMDA) injection in the mouse. The mRNA expression of sphingosine kinase (SphK1/SphK2) was examined by quantitative real-time polymerase chain reaction (qRT-PCR). The expressions of SphK1/2, S1P, S1P-receptor (S1PR), glial fibrillary acidic protein (GFAP), Iba1, and CD31 were examined by immunostaining. Retinal sphingolipids and ceramides were quantified by liquid chromatography with tandem mass spectrometry. The neuroprotective effect of the sphingosine kinase inhibitor (SKI) on RGC death was assessed by RGC count and Terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. Further, the in vitro effect of SKI was investigated using rat primary cultured RGCs and glial cells. In addition, MG5 cells and A1 cells, which were mouse microglia and astrocyte cell-line, were also used. The expression of cleaved-caspase-3, GFAP, and Iba1 in RGCs, primary glial cells, MG5 cells, and A1 cells was assessed by immunostaining. NMDA injection resulted in mRNA upregulation of SphK1; however, SphK2 was reduced in the mouse retina. SphKs, S1P, S1PR1, S1PR2, and GFAP expression increased in the early-stage NMDA group, whereas S1P and GFAP were higher in the late-stage NMDA + SKI group. In the NMDA group, S1P expression was lower whereas sphingosine, C20, C22, and C24 ceramides showed higher levels. The proportion of very-long-chain ceramide was elevated in the NMDA group but reduced in the NMDA + SKI group. SKI treatment significantly increased RGC survival in retinal wholemount analysis and decreased apoptosis in the ganglion cell layer and inner nuclear layer. In vitro, SKI suppressed excitotoxic RGC death, cleaved-caspase-3 expression, and activated glial cells. The findings in the present study provide the first evidence demonstrating the involvement of sphingolipid rheostat in the neuroprotection against excitotoxic RGC death. Therefore, regulation of sphingolipid rheostat might serve as a potential therapy for retinal degenerative disease.

RasV12 Expression in Microglia Initiates Retinal Inflammation and Induces Photoreceptor Degeneration

Purpose

The role of activated retinal microglia in driving retinal degeneration has been implicated in a number of in vivo disease models. Here, we investigated the primary consequences of microglial activation by the specific expression of constitutively active Ras in microglia in a transgenic mouse model before the onset of any degenerative changes in the retina.

Methods

The double transgenic lines CAG-LSL-RasV12-IRES-EGFP; Cx3cr1^CreER/+ (Cx3cr1-RasV12 mice) and CAG-LSL-EGFP; Cx3cr1^CreER_+ (control mice) were generated. The expression of RasV12 was induced in microglia by tamoxifen administration, and the retinas were examined by immunohistochemistry of frozen sections, RT-qPCR, and live imaging.

Results

RasV12 expression in retinal microglial cells promoted cell proliferation, cytokine expression, and phagocytosis. RasV12-expressing microglia migrated toward the inner and outer layers of the retina. Examination of glial fibrillary acidic protein (GFAP) expression revealed activation of Müller glia in the retina. We also observed loss of the photoreceptors in the outer nuclear layer in close proximity to microglial cells. However, no significant neurodegeneration was detected in the inner nuclear layer (INL) or ganglion cell layer (GCL). The morphology of RasV12-expressing microglia in the GCL and INL retained more ramified features compared with the predominantly-ameboid morphology found in outer retinal microglia.

Conclusions

The expression of RasV12 is sufficient to activate microglia and lead to photoreceptor degeneration. Neurons in the inner side of the retina were not damaged by the RasV12-activated microglia, suggesting that microenvironment cues may modulate the microglial phenotypic features and effects of microglial activation.

Setd1a Plays Pivotal Roles for the Survival and Proliferation of Retinal Progenitors via Histone Modifications of Uhrf1

Purpose

The trimethylation of histone H3 at lysine 4 (H3K4me3) facilitates transcriptional gene activation, and Setd1a is the methyltransferase specific to H3K4. H3K4me3 has been reported to regulate rod photoreceptor differentiation; however, the roles H3K4me3 plays in retinal progenitor cell (RPC) proliferation and differentiation during early retinal development remain unclear.

Methods

Using an in vitro retinal explant culture system, we suppressed the expression of Setd1a by introducing shSetd1a. We examined the expression level and H3K4me3 level of genes by RNA Sequencing and ChIP assay, respectively.

Results

We found that Setd1a depletion resulted in increased apoptosis and proliferation failure in late RPCs. Expression of wild-type SETD1A, but not SETD1A that lacked the catalytic SET domain, reversed the shSetd1a-induced phenotype. RNA Sequencing revealed that proliferation-related genes were downregulated upon shSetd1a expression. Based on publicly available H3K4me3-ChIP sequencing data of retinal development, we identified Uhrf1 as a candidate target gene of Setd1a. The expression of shSetd1a led to a decrease in Uhrf1 transcript levels and reduced H3K4me3 levels at the Uhrf1 locus. Increased apoptosis and the suppression of proliferation in late RPCs were observed in retinal explants expressing shUhrf1, similar to the outcomes observed in shSetd1a-expressing retinas. The overexpression of UHRF1 did not rescue shSetd1a-induced apoptosis, but reversed the suppression of proliferation.

Conclusions

These results indicate that Setd1a contributes to the survival and proliferation of retinal cells by regulating histone methylation, Setd1a regulates Uhrf1 expression, and these two molecules cooperate to regulate RPC survival and proliferation.

Foxr2 promotes formation of CNS-embryonal tumors in a Trp53-deficient background

BACKGROUND

Embryonal tumors in the central nervous system (CNS) are primary, aggressive, and poorly differentiated pediatric brain tumors. We identified forkhead box R2 (Foxr2) as an oncogene for medulloblastoma through a transposon-based insertional mutagenesis screen. Foxr2 translocation has been identified in a subset of human embryonal tumors of the CNS, designated as CNS neuroblastoma with Foxr2 activation (CNS NB-Foxr2); however, the in vivo functions of Foxr2 remain elusive.

METHODS

We analyzed the effect of Foxr2 overexpression in the mouse brain by generating a transgenic strain that expresses Foxr2 in the entire brain under a transformation related protein 53 (Trp53)-deficient background. We performed histological analysis of tumors and characterized tumor-derived sphere-forming cells. We investigated gene expression profiles of tumor-derived cells.

RESULTS

Foxr2 and Trp53 loss promoted tumor formation in the olfactory bulb (OB) and brainstem (BS). The tumors showed the common morphological features of small round blue cell tumors, exhibiting divergent, mainly neuronal and glial, patterns of differentiation, which corresponds to the definition of CNS-embryonal tumors. Importantly, all mice developed CNS-embryonal tumors. In the OB, early proliferative lesions consisting of oligodendrocyte transcription factor 2 (Olig2+) cells were observed, indicating that Foxr2 expression expanded Olig2+ cells in the OB. Tumor-derived cells formed spheres in vitro and induced tumors that recapitulated the parental tumor upon transplantation, indicating the presence of tumor-initiating cells. Gene expression profiling revealed that OB and BS tumor cells were enriched for the expression of the genes specific to CNS NB-Foxr2.

CONCLUSION

Our data demonstrate that Foxr2 plays a causative role in the formation of CNS-embryonal tumors.

Minocycline decreases CCR2-positive monocytes in the retina and ameliorates photoreceptor degeneration in a mouse model of retinitis pigmentosa

Retinal inflammation accelerates photoreceptor cell death caused by retinal degeneration. Minocycline, a semisynthetic broad-spectrum tetracycline antibiotic, has been previously reported to rescue photoreceptor cell death in retinal degeneration. We examined the effect of minocycline on retinal photoreceptor degeneration using c-mer proto-oncogene tyrosine kinase (Mertk)^−/−Cx3cr1^GFP/+Ccr2^RFP/+ mice, which enabled the observation of CX3CR1-green fluorescent protein (GFP)- and CCR2-red fluorescent protein (RFP)-positive macrophages by fluorescence. Retinas of Mertk^−/−Cx3cr1^GFP/+Ccr2^RFP/+ mice showed photoreceptor degeneration and accumulation of GFP- and RFP-positive macrophages in the outer retina and subretinal space at 6 weeks of age. Mertk^−/−Cx3cr1^GFP/+Ccr2^RFP/+ mice were intraperitoneally administered minocycline. The number of CCR2-RFP positive cells significantly decreased after minocycline treatment. Furthermore, minocycline administration resulted in partial reversal of the thinning of the outer nuclear layer and decreased the number of apoptotic cells, as assessed by the TUNEL assay, in Mertk^−/−Cx3cr1^GFP/+Ccr2^RFP/+ mice. In conclusion, we found that minocycline ameliorated photoreceptor cell death in an inherited photoreceptor degeneration model due to Mertk gene deficiency and has an inhibitory effect on CCR2 positive macrophages, which is likely to be a neuroprotective mechanism of minocycline.

Jmjd3 Plays Pivotal Roles in the Proper Development of Early-Born Retinal Lineages: Amacrine, Horizontal, and Retinal Ganglion Cells

Purpose

Trimethylation of histone H3 at lysine 27 (H3K27me3) is a critical mediator of transcriptional gene repression, and Jmjd3 and Utx are the demethylases specific to H3K27me3. Using an in vitro retinal explant culture system, we previously revealed the role of Jmjd3 in the development of rod bipolar cells; however, the roles of Jmjd3 in the development of early-born retinal cells are unknown due to limitations concerning the use of retinal explant culture systems. In this study, we investigated the roles of Jmjd3 in the development of early-born retinal cells.

Methods

We examined retina-specific conditional Jmjd3 knockout (Jmjd3-cKO) mice using immunohistochemistry and quantitative reverse transcription PCR and JMJD3 binding to a target locus by chromatin immunoprecipitation analysis.

Results

We observed reductions in amacrine cells (ACs) and horizontal cells (HCs), as well as lowered expression levels of several transcription factors involved in the development of ACs and HCs in the Jmjd3-cKO mouse retina. JMJD3 bound the promoter regions of these transcription factors. Notably, an elevated number of retinal ganglion cells (RGCs) was observed at embryonic stages, whereas RGCs were moderately reduced at later postnatal stages in the Jmjd3-cKO retina. We also observed reduced expression of Eomes, which is required for the maintenance of RGCs, as well as lower H3K27me3 level and lower JMJD3 binding in the promoter region of Eomes in RGC-enriched cells.

Conclusions

The results indicated that Jmjd3 has critical roles in the development of early-born retinal subtypes, and suggested biphasic roles of Jmjd3 in RGC production and maintenance.

Strongly correlated superconductivity in a copper-based metal-organic framework with a perfect kagome lattice

Metal-organic frameworks (MOFs), which are self-assemblies of metal ions and organic ligands, provide a tunable platform to search a new state of matter. A two-dimensional (2D) perfect kagome lattice, whose geometrical frustration is a key to realizing quantum spin liquids, has been formed in the π - d conjugated 2D MOF [Cu₃(C₆S₆)] _n (Cu-BHT). The recent discovery of its superconductivity with a critical temperature T _c of 0.25 kelvin raises fundamental questions about the nature of electron pairing. Here, we show that Cu-BHT is a strongly correlated unconventional superconductor with extremely low superfluid density. A nonexponential temperature dependence of superfluid density is observed, indicating the possible presence of superconducting gap nodes. The magnitude of superfluid density is much smaller than those in conventional superconductors and follows the Uemura's relation of strongly correlated superconductors. These results imply that the unconventional superconductivity in Cu-BHT originates from electron correlations related to spin fluctuations of kagome lattice.