P-175 Relationship Between oocytes with sERC and Ploidy

Study question

We investigated the effects of the presence or absence of sERC on subsequent embryonic development and the ploidy of embryos.

Summary answer

The acquisition rates for euploidy embryos were similar to those for the embryos derived from oocytes without smooth endoplasmic reticulum cluster (sERC).

What is known already

The effects of the presence of sERC have been reported on embryonic development processes and pregnancy rate after embryo transfer (ET). In this study, we investigated the effects of the presence of sERC not only on embryonic development and pregnancy rate, but also on the ploidy of embryos from the oocytes with sERC.

Study design, size, duration

The subjects comprised women from whom oocytes were collected from January 2019 to November 2021. The group with the oocytes with sERC was designated as sERC(+), and the other group without sERC as sERC(-).

Participants/materials, setting, methods

Retrospective analysis was performed using a time-lapse system (EmbryoScope+). They were divided into two groups according to the presence of sERC. The groups were compared for fertilization rate, degeneration rate, abnormal fertilization rate (1PN, 3PN, 2.1PN), blastocyst rate, and good-quality-blastocyst rate after ICSI. The prognosis of the transferred embryos was followed up on. In addition, the embryos that were subjected to NGS analysis were investigated for effects of the presence of sERC on their ploidies.

Main results and the role of chance

The sERC(+) group exhibited a significantly lower fertilization rate (74.8%) compared to that of the sERC(-) group (82.4%, P < 0.01). The sERC(+) group exhibited a significantly higher abnormal fertilization rate (14.8%) compared to that of the sERC(-) group (6.6%, P < 0.01). The sERC(+) group showed a significantly higher blastocyst formation rate (57.4%) compared to the sERC(-) group (45.2%, P < 0.01). With respect to after ET prognosis, eight women gave birth with no confirmed congenital anomality. At the very least, the presence of sERC has been shown to have no effect on childbirth. The investigation on ploidy showed that the oocytes in the sERC(+) group included 24.2% euploidy (8/33), 9.1% mosaic (3/33), and 66.7% aneuploidy (22/33) embryos, while the oocytes in the sERC(-) group included 30.4% euploidy (137/451), 12.4% mosaic (56/451), and 57.2% aneuploidy (258/451) embryos. Thus, there was no difference due to the presence of sERC. Three out of the eight euploidy blastocysts in the sERC (+) group had been transferred, one of which reached childbirth.

Limitations, reasons for caution

PGT-A is still under clinical research in Japan.

Wider implications of the findings

Many reports suggested that oocytes with sERC can be used as embryos appropriate for transfer when they develop into blastocysts. The investigation into the ploidy of sERC(+)-derived blastocysts in this study confirmed that the presence of sERC did not affect the ploidy of embryos and that these embryos were transferable.

Trial registration number

not applicable

P-163 Effects of Early Modes of Cell Division on Blastocyst Ploidy

Study question

Abnormal cleavage (AC) has been confirmed at early development. We performed an NGS analysis on AC-derived blastocysts to investigate ploidy of the resulting embryos.

Summary answer

Group in which AC occurred during second division showed significantly higher rates for embryos appropriate for transfer than group where AC occurred during first division.

What is known already

Early division is important in embryogenesis and serves as an indicator of subsequent embryonic development. The occurrence of AC during early development can be identified with the advent of the time-lapse incubator, which in turn has led to difficulties in determining whether such AC-derived blastocysts can be used embryo transfer. In this study, we performed NGS analysis on AC-derived blastocysts to investigate the ploidy of the resulting embryos.

Study design, size, duration

The subjects comprised women from whom oocytes were collected for NGS analysis from January 2019 to November 2021. Retrospective analysis was performed using a time-lapse system (EmbryoScope+). Embryos were categorized into two groups: those with abnormal divisions observed during the first and second divisions and those in which normal divisions were observed in the same cycle.

Participants/materials, setting, methods

The group with AC observed was designated the AC group and the other with normal divisions as the Normal Cleavage (NC) group. Within the AC group, the subgroup with AC observed during first division was designated as the First (AC-F) group and the subgroup with AC observed during second division as the Second (AC-S) group for comparing the acquisition rates for euploidy embryos and embryos appropriate for transfer.

Main results and the role of chance

The AC group (17.3%) showed a significantly lower rate of good blastocyst formation than did the NC group (53.4%) (P < 0.01). The cutoff point for mosaicism was defined as > 20% of abnormal cells. Percentage <20 were classified as normal (euploid); >80, abnormal (aneuploidy); and 20-80, mosaic. Using a cutoff of 50% to differentiate ‘‘low’’ mosaics from ‘‘high’’ mosaics. There was no difference between the two groups in the acquisition rates for euploidy embryos (30.8-35.1%) and the embryos appropriate for transfer, including low-mosaic ones (44.3-46.1%). There also was no difference in the acquisition rates for euploidy embryos (24.0-37.0%) between the AC-F and AC-S groups. However, the AC-S group (59.3%) showed significantly higher acquisition rates than the AC-F group (32.0%) for the embryos appropriate for transfer, including low-mosaic ones (P < 0.05).

Limitations, reasons for caution

PGT-A is still under clinical research in Japan.

Wider implications of the findings

The group in which AC occurred during second division showed significantly higher acquisition rates for the embryos appropriate for transfer than the group in which AC occurred during first division. This indicates that the most important factor for identifying euploidy embryos is going through the two-cell phase during first division.

Trial registration number

not applicable

Changes of ROS during a two-day ultra-marathon race

To assess oxidative stress (OS) induced by endurance exercise, concentrations of serum reactive oxygen species (ROS) were determined in 70 Japanese male amateur runners completing a two-day ultra-marathon race. Serum ROS levels were analyzed at three time points: before the race (baseline), after the 1st day race (mid-race), and after the 2nd day race (goal) (post-race). The means (SE) of ROS were 151.4(3.7) (U. CARR.), 168.7(4.4), and 156.8(4.4), respectively. Significant positive trends were noted between age and serum ROS concentrations at the three race points (p<0.05 for all). After adjusting for age, BMI and average monthly running distance, the baseline serum ROS concentrations were positively associated with completion times of the first-day race, in particular (p<0.05), suggesting that the concentrations may predict physical performance. The ROS production increased at mid-race (p<0.05), but the levels returned to baseline levels at post-race, indicating that an antioxidant defense system may develop post-race to reduce OS.

Changes of mental stress biomarkers in ultramarathon

We investigated the possible influence of an exhaustive physical exercise on mental stress biomarkers (serotonin, tryptophan, and beta-endorphin) along with dopamine, noradrenaline and free fatty acids in an ultramarathon race in which 45 km was run on the first day and 90 km on the second. We obtained serum samples at 6 different time points during and after the race from 18 Japanese male runners who completed the marathon. Overall changes of serum serotonin and tryptophan concentrations were statistically significant according to ANOVA for repeated measurements (p < 0.05). Serum serotonin levels elevated rapidly on the first day with the post hoc Tukey's test. Tryptophan concentrations inversely decreased during the race, possibly because of utilization for synthesis of serotonin. Levels of beta-endorphin appeared to increase on the first and second days, but were not statistically significant. In conclusion, serum serotonin, tryptophan and beta-endorphin appeared to be used for mental stress markers in physical exercise.

Changes of Urinary 8-Hydroxydeoxyguanosine Levels during a Two-Day Ultramarathon Race Period in Japanese Non-Professional Runners

Using the urinary 8-hydroxydeoxyguanosine (8-OHdG) concentration, effects of participation in a two-day ultramarathon race period on oxidative DNA damage were investigated in Japanese nonprofessional runners. Before the first day (baseline), after the first day (mid-race) of 40-km running, and after the second day (post-race) of 90 km running, biomaterials were successfully sampled from 95 participants (males, 79; females, 16) who completed the full race. We analyzed urine for 8-OHdG and blood for aspartate aminotransferase (AST), creatine phosphokinase (CPK) and myoglobin, and evaluated fluctuation in the values at three sampling time points. Adjusted baseline urinary 8-OHdG levels (microg/g creatinine) (mean +/- standard deviation) showed no significant differences between males and females, at 2.85 +/- 1.17 and 3.04 +/- 1.56, respectively. In males, mid-race urinary 8-OHdG levels rose to 3.29 +/- 1.15 (p < 0.01), but then returned to 2.73 +/- 1.16 at the post-race time point (p < 0.01). In females, a similar increase to 3.32 +/- 1.47 and subsequent decline to 2.80 +/- 1.47 were noted. In contrast, AST, CPK and myoglobin were increased at both mid- and post-time points and particularly the latter, independent of the sex. Extreme prolonged exercise in a two-day ultramarathon race period causes oxidative DNA damage but antioxidant repair systems are apparently induced to protect against oxidative DNA stress with physical exercise.

[Recovery from out-of-hospital cardiac arrest after mild hypothermia: report of two cases]

We report two patients with out-of-hospital cardiac arrest who recovered after hypothermia therapy. A 25-year-old man and a 16-year-old boy were transferred to our hospital after cardiopulmonary arrest due to idiopathic ventricular fibrillation and hypertrophic cardiomyopathy, respectively. We carried out hypothermia therapy using cooling blankets, and the patients were maintained at 32-33 degrees C for 96 and 36 h, respectively. After slow rewarming, they regained consciousness and recovered. During hypothermia, hypokalemia and arrhythmia occurred. Their arrest times (no spontaneous circulation and no CPR) were 10 min and 8 min, and CPR times (no spontaneous circulation while CPR was being performed) were 24 min and 20 min, respectively. In cases where the duration of ischemia is prolonged, the prognosis is expected to be poor. Therefore, we believe that hypothermia therapy is beneficial for such patients.

[Left ventricular blood flow dynamics caused by ventricular premature contraction: pulsed Doppler echocardiographic study]

Cardiac function at the time of ventricular premature contractions (VPC) is influenced by the coupling interval or the site of those origin. Clinical and experimental studies of the effects of VPC on intracardiac pressure dynamics have been performed; however, little is known about left ventricular blood flow dynamics. This study was attempted to determine the characteristics of blood flow dynamics in respect to the site of origin of VPC using pulsed Doppler echocardiography. The subjects consisted of 18 cases with VPC but without apparent organic heart disease. Seven cases had VPCs with a left bundle branch block pattern suggesting possible origin in the right ventricle. The other 11 cases had VPCs with a right bundle branch block pattern indicating the left ventricular origin. With the probe in the apical position, the blood flow patterns of the left ventricular outflow, central and inflow tracts were examined. The results were as follows; 1. Except for one case with shortened coupling interval, all six cases with VPCs originated from the right ventricle showed preservation of left ventricular ejection flow. 2. In two of the three cases with VPC which originated from the left ventricle and with left axis deviation, systolic flow in the left ventricular central area showed "back flow" to the apex. Ejection flow at the outflow tract was markedly diminished or disappeared in all three cases. 3. In all eight cases with VPC which originated from the left ventricle and with right axis deviation, ejection flow was slightly disturbed both in the left ventricular outflow and in the central area. 4. Ejection flow volume assessed by velocity integral indicated similar dynamics as did the ejection flow velocity. 5. In left ventriculography, asynchrony due to dyskinetic motion of the anteroapical wall was observed at the times of VPCs with left axis deviation. In conclusion, the patterns of left ventricular ejection flow dynamics depend on the site of origin of VPCs. This disturbed flow is more apparent in VPCs originating from the left ventricle compared to the right ventricle. This is especially true in cases with left axis deviation, in which VPCs arise from the posterior site of the left ventricle.

A new micromethod for colorimetric determination of zinc in serum

A simple micromethod with a colorimetric reagent of high sensitivity was developed for the determination of zinc in serum. For the color reagent 2-(2-pyridylazo)-5-dimethylaminophenol (PADAP) was used. Coefficients of variation of the within-day precision were 6.65 and 2.24% for zinc standard at concentrations of 0.1 and 0.5 microgram/ml, respectively. The mean recovery by this method was 101.2% (S.D.: 3.56%). Zinc concentrations measured by the above method showed good agreement with those by atomic absorption spectrophotometry, with a correlation coefficient of 0.934. Serum zinc values of 50 healthy adults (38 females, 12 males) ranged from 63 to 116 microgram/100 ml (mean: 89.68 microgram/100 ml, Sd.: 13.28 microgram/100 ml).