Influence of Surface Pretreatment on the Bond Strength of a Resin Luting Cement to Saliva-contaminated Enamel and Dentin

OBJECTIVES

This study aimed to evaluate the influence of surface pretreatment on the shear bond strength (SBS) of a resin luting cement to enamel and dentin with saliva contamination. The surface free energies (SFE) of the adherent surfaces were also determined.

METHODS AND MATERIALS

Bovine enamel and dentin were used in this study. For the saliva-contamination, human saliva was applied to the adherent surface for 60 seconds and then air-dried, and the specimens without saliva contamination served as controls. One group of contaminated surfaces was untreated (SC), and the others were pretreated with Katana Cleaner (KC), Multi Etchant (ME), or Ultra-Etch (UE). Fifteen specimens were prepared to measure the SBS for each test group. The mixed resin luting cement paste was applied to the alumina-blasted surface of a stainless-steel rod and placed on the prepared tooth surface. The luting cement was light irradiated for 40 seconds. The bonded specimens were stored for 24 hours at 37°C and half of the bonded specimens underwent 10,000 thermal cycles. The SBS and SFE of the specimens after different pre-treatments were measured.

RESULTS

The two-way ANOVA revealed that the factors of pretreatment agent and storage condition had a significant effect on the SBS to enamel and dentin. The SFE values of the SC group were significantly lower than those of the other groups in both enamel and dentin. The SFE of pretreated surface was material dependent.

CONCLUSIONS

A pretreatment agent containing functional monomers was shown to be effective in removing saliva contaminants and in creating an effective bonding surface for the resin luting cement.

Impact of dietary habits on renal function in Saku, a rural Japanese town: a cohort study

BACKGROUND

High protein intake leads to a decline in renal function in the advanced stages of chronic kidney disease (CKD). An effective diet for maintaining renal function in healthy individuals or patients in the early stages of CKD has not been established. This cohort study was conducted in Saku, Nagano Prefecture, Japan, to investigate the impact of dietary habits on renal function.

METHODS

In this cross-sectional cohort study, we used the Saku Control Obesity Program (UMIN000016892), including 4,446 participants who submitted a brief-type self-administered diet history questionnaire and underwent routine physical examination. The amount of food intake was divided into quartiles. After adjusting for age and sex, multivariate logistic regression analysis was used to calculate the odds ratio (OR) for the risk of developing CKD (estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m2).

RESULTS

In total, 3,899 participants were analyzed. The overall prevalence of patients with eGFR < 60 mL/min/1.73 m2 was 11% (n = 434, male; 7.1%, female; 4.1%). The groups with a high intake of chicken (approximately 63.4 g/day, adjusted OR: 0.632, P = 0.003), natto (fermented bean; approximately 21.7 g/day, adjusted OR: 0.679, P = 0.01), and plant protein (approximately 0.8 g/ideal body weight/day, adjusted OR: 0.695, P = 0.042) showed a low risk of developing CKD compared to the group with the lowest intake.

CONCLUSIONS

Our cross-sectional study showed that the intake of chicken meat, natto, and plant protein was associated with high eGFR levels. This information can be of value for preventing CKD incidence in healthy Japanese individuals.

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.

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.

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.

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.

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.

Dietary Approaches to Stop Hypertension via Indo-Mediterranean Foods, May Be Superior to DASH Diet Intervention

Western-type diet with high salt and sugar, sedentary behavior, obesity, tobacco and alcoholism are important risk factors for hypertension. This review aims to highlight the role of western diet-induced oxidative stress and inflammation in the pathogenesis of hypertension and the role of various types of diets in its prevention with reference to dietary approaches to stop hypertension (DASH) diet. It seems that it is crucial to alter the western type of diet because such diets can also predispose all CVDs. Western diet-induced oxidative stress is characterized by excessive production of reactive oxygen species (ROS) with an altered oxidation-reduction (redox) state, leading to a marked increase in inflammation and vascular dysfunction. Apart from genetic and environmental factors, one important cause for differences in the prevalence of hypertension in various countries may be diet quality, deficiency in functional foods, and salt consumption. The role of the DASH diet has been established. However, there are gaps in knowledge about the role of some Indo-Mediterranean foods and Japanese foods, which have been found to decrease blood pressure (BP) by improving vascular function. The notable Indo-Mediterranean foods are pulses, porridge, spices, and millets; fruits such as guava and blackberry and vegetables, which may also decrease BPs. The Japanese diet consists of soya tofu, whole rice, in particular medical rice, vegetables and plenty of fish rich in fish oil, fish peptides and taurine that are known to decrease BPs. Epidemiological studies and randomized, controlled trials have demonstrated the role of these diets in the prevention of hypertension and metabolic diseases. Such evidence is still meager from Japan, although the prevalence of hypertension is lower (15-21%) compared to other developed countries, which may be due to the high quality of the Japanese diet. Interestingly, some foods, such as berries, guava, pumpkin seeds, carrots, soya beans, and spices, have been found to cause a decrease in BPs. Omega-3 fatty acids, fish peptide, taurine, dietary vitamin D, vitamin C, potassium, magnesium, flavonoids, nitrate and l-arginine are potential nutrients that can also decrease BPs. Larger cohort studies and controlled trials are necessary to confirm our views.

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

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.

Dietary therapy with low protein genmai (brown rice) to improve the gut-kidney axis and reduce CKD progression

Low protein rice can be part of a nutritionally adequate dietary pattern in the prevention of chronic kidney disease. We developed a low protein fermented genmai (brown rice) LPFG) to improve chronic kidney disease (CKD) management. The principal functional features of brown rice are retained in LPFG, lessening the negative spiral of gut-kidney associative spiral attributable to uremic dysbiosis and a leaky gut. LPFG is characterized by (1) an energy value the same as white rice, (2) a protein content less than 0.2 g/ 100 g, (3) a potassium content almost zero, (4) phosphorus less than a quarter that of conventional rice, (5) the presence of dietary fiber, (6) having γ-oryzanol, and (7) antioxidant activity. Dietary therapy for CKD patients is challenged by the joint needs to provide enough energy and to restrict protein. Patients replaced staple foods with LPFG without side dish restriction. Preliminary study of intervention with 3 months of LPFG reduced constipation probably by increased Blautia wexlerae, Bifidobacteria, acetic acid, and a decrease in potentially harmful bacteria. Protein intake decreased from 60 to 50 g per day. Urinary protein excretion decreased from 510 to 300 mg per day, and β2-microglobulin from 926 to 250 μg/L. Adherence to the LPFG diet enabled improvement in glomerular and tubular function.

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.