Cytogenetic validation of DS02R1-estimated dose for atomic bomb survivors in Hiroshima and Nagasaki with FISH

INTRODUCTION

For Hiroshima and Nagasaki survivors, it has not been possible to calculate individual doses from the cytogenetic data and compare them with the physically estimated doses. This is because the cytogenetic studies used solid Giemsa staining which only provides the percent of cells bearing at least one stable-type aberration (most of the unstable-type aberrations had already disappeared), and a gamma-ray dose plus a 10-times neutron dose was used to integrate the data for both cities.

OBJECTIVES

To compare the FISH-derived gamma-ray dose with the DS02R1-derived gamma-ray dose after correcting for a contribution of the neutron dose. It was also an attempt to determine if the frequency of stable-type aberrations had remained unchanged after the exposure.

METHODS

Stable exchange-type aberration data was obtained using the 2-color FISH method from 1,868 atomic bomb survivors in Hiroshima and Nagasaki. The collected frequency was first extended to a genome-equivalent frequency. Then, by using known induction rates of exchange-type aberrations in vitro caused by neutrons and gamma-rays, respectively, and the mean relationship between the neutron and gamma-ray doses in the DS02R1 estimates for the survivors, the gamma-ray effect was estimated from the total yield of translocations.

RESULTS

It was found that over 95% of individual cytogenetic gamma-ray doses fell within the expected range of plus/minus about 1 Gy from the DS02R1 dose and the mean slope for the linear regression was 0.98, which reassures us of the validity of the DS02R1 study.

CONCLUSIONS

The present results demonstrate the validity of the individual DS02R1 doses, and that the frequency of stable-type aberrations in blood lymphocytes did not decay over the years, and thus is useful for retrospective dose evaluations of exposures which took place in the distant past.

Safety evaluation of the use of calcineurin inhibitor to prenatal and postpartum women in Japan from a health administrative database

BACKGROUND

To investigate the use of calcineurin inhibitors (CNIs) in pregnant Japanese women and to evaluate their safety in infants.

METHODS

Data were extracted from the claims database of the Japan Medical Data Center. The prevalence of CNIs was evaluated 180 days before pregnancy onset, during pregnancy, and within180-days post partum. We investigated the characteristics of the infants, including the presence of major malformations and their diagnoses, for 1 year after birth.

RESULTS

A total of 91,865 pregnancies in 80,049 women were included. Fifty-three women were prescribed CNIs between 180-day before pregnancy onset and 180-day postpartum; 35 of the 53 women were prescribed the drugs during pregnancy, and 10 of their infants were born preterm. Three were diagnosed with major congenital malformations, such as patent ductus arteriosus. Six preterm infants presented with infant respiratory distress syndrome.

CONCLUSIONS

No congenital anomalies were clearly attributable to the use of CNIs during pregnancy.

Initial 30 cholecystectomy procedures performed with the Senhance digital laparoscopy system

PURPOSE

The Senhance digital laparoscopy system (SDLS) is a novel platform developed for digitization in endoscopic surgery. This retrospective study aimed to evaluate the short-term outcome in the initial 30 consecutive patients.

METHODS

SDLS cholecystectomies were performed in 30 consecutive patients (13 male, 17 female) by a single surgeon from September 2020 to March 2022. The patients' median age (range) was 77.5 (27-82) years, and median body mass index was 23.3 (19-38) kg/m² . Four trocars were used, three of which were docked to manipulator arms of the SDLS. Surgical procedures performed with the SDLS were almost the same as those by conventional surgery.

RESULTS

Median docking time, cockpit time, and operation time in minutes were 4 (3-13), 34 (13-81), and 69 (47-201), respectively. Operation time after the sixth case tended to shorten compared with that for the initial five cases. Three cases (10%) were converted to conventional laparoscopic surgery due to severe cholecystitis, but none required conversion to open surgery. Postoperative complications of Clavien-Dindo grade ≥II were not observed.

CONCLUSION

This retrospective study showed that cholecystectomy using the SDLS appeared to be safe and feasible in limited cases without severe inflammation.

Relationship between the combination of polyunsaturated fatty acids intake and psychological distress during pregnancy: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

No studies have examined the association of the combination of n-3 polyunsaturated fatty acids (PUFAs) and n-6 PUFAs intake with psychological distress during pregnancy. To examine these associations, we divided Japanese pregnant women into 25 groups based on combining quintiles of n-3 PUFAs intake and quintiles of n-6 PUFAs intake. We conducted multivariable logistic regression analyses to assess the risk of psychological distress during pregnancy (Kessler Psychological Distress Scale ≥ 5 or 13). Compared to the third quintile of both n-3 PUFAs and n-6 PUFAs intake, the groups with unbalanced intake, high intake of both, and low intake of both were associated with a higher risk of both Kessler Psychological Distress Scale ≥ 5 and 13 in early and mid-pregnancy. Further research is needed to identify the precise combination of n-3 PUFAs and n-6 PUFAs intake associated with the lowest psychological distress during pregnancy.

Maternal psychological distress during and after pregnancy and atopic dermatitis in children

Background

Previous studies reported the association between maternal psychological distress (PD) during or after pregnancy and atopic dermatitis in children. However, studies examining the association from both pre- and post-natal aspects are limited.

Methods

We analysed data from 6,366 mother-child pairs who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study in Japan. Mothers were categorised into four groups of PD (K6 scores ≥5) during early pregnancy and one year after delivery; no PD in both periods, prenatal PD only, postnatal PD only, and PD in both periods. Mothers reported on their children's atopic dermatitis at age two using the International Study of Asthma and Allergies in Childhood (ISAAC). Multivariate logistic regression analysis was conducted to examine the association between maternal PD and atopic dermatitis in children adjusting for maternal age at delivery, maternal education, maternal smoking during early pregnancy, maternal history of atopic diseases, paternal history of atopic diseases, preterm birth, parity, and child's sex.

Results

The study population included 51.9% without PD in both periods, 14.6% with prenatal PD only, 14.0% with postnatal PD only, and 19.4% with PD in both periods. The prevalence of atopic dermatitis in children at age two was 18.8%. Mothers with postnatal PD only and mothers with PD in both periods had higher risks of children's atopic dermatitis compared with mothers without PD in both periods; the adjusted odds ratios (95% confidence intervals) were 1.37 (1.14-1.65) and 1.38 (1.17-1.63), respectively. The corresponding odds ratio (95% confidence interval) of mothers with prenatal PD only was 1.08 (0.89-1.31).

Conclusions

Postnatal PD was associated with an increased risk of atopic dermatitis in children. This finding suggests the importance for monitoring mental health among postpartum women.

Key messages

Postnatal PD has significant effects on atopic dermatitis in children. This study is a first study to examine the association between maternal PD and children’s atopic dermatitis in Japan. Improvements of postnatal care including social support might be effective in preventing atopic dermatitis in children.

0652 A Novel Cognitive-Behavioral Therapy to Increase PAP Adherence in Veterans With Posttraumatic Stress Disorder: Preliminary Results

Introduction

The occurrence of obstructive sleep apnea (OSA) is high in veterans with posttraumatic stress disorder (PTSD). Our previous research on OSA in Vietnam-era veterans found that 69% had an AHI≥10 (Yesavage, 2012). Efficacious treatments are available for OSA, PAP therapy; however, veterans with OSA frequently fail to use them (Yesavage, 2012; Kuna, 2011). Of the veterans diagnosed with OSA, 63% were not using their prescribed PAP device. The reasons for low PAP adherence include discomfort using PAP and psychological barriers. We developed a novel cognitive-behavioral therapy (CBT) intervention to increase PAP adherence in veterans with PTSD and OSA, called CBT-OSA.

Methods

Participants included 37 veterans age 18+ from clinics at VA Palo Alto. Participants were randomly assigned to CBT-OSA or an education arm. All participants received treatment as usual in VA Pulmonary Service or a community-based Sleep Medicine Center. Participants in CBT-OSA received therapy from a Clinical Psychologist. The other veterans received education sessions. All participants received weekly, individual sessions during the first four weeks of PAP treatment. Average mask on time was calculated for each participant during week 1-4 of PAP use.

Results

An independent samples t-test was conducted to compare average mask on time in the CBT-OSA and education conditions. There was a significant difference in the average mask on time for CBT-OSA (M=235.33, SD=139.22) and education (M=136.68; SD=149.19); t(35)=-2.08, p=0.045. These results suggest that veterans who received the CBT treatment increased their PAP use compared to the veterans in the education condition.

Conclusion

CBT-OSA has shown early efficacy. CBT-OSA increased PAP adherence in veterans with PTSD compared to veterans in the education condition. Veterans receiving CBT-OSA demonstrated a longer average mask on time compared to veterans in the education condition. We are following the participants for one year to examine if CBT-OSA fosters long-term PAP adherence.

Support

This research is supported by the Research Service of the Department of Veterans Affairs (Grant Number 1I01RX001799-01A2).

0575 Sleep Monitoring with a Single Channel EEG Recorder in Patients with Psychiatric Disorders

Introduction

The gold standard of sleep measurement has been laboratory polysomnography (PSG). However, electrodes and cables can cause discomfort, and exposure to an unfamiliar environment can cause the “first-night effect.” Difficulty falling asleep or maintaining sleep, poor sleep quality, and nightmares are some of the key clinical symptoms observed among individuals with psychiatric disorders. Those suffering from sleep disorders often present with symptoms of discontent with regard to sleep quality, timing, and quantity, and these symptoms have an adverse impact on function and quality of life. A minimally invasive technique would be preferable in patients with psychiatric disorders, who tend to be sensitive to environmental change. Accordingly, we evaluated the performance of a single-channel electroencephalography (EEG)-based sleep monitoring system in patients with psychiatric disorders.

Methods

Fifty-nine patients undergoing PSG were enrolled in this study. Single-channel EEG sleep monitoring was performed simultaneously with PSG. PSG and the EEG recordings were used to evaluate sleep parameters, such as total sleep time (TST), sleep efficiency, rapid eye movement (REM) sleep, light sleep (stages N1 and N2), and deep sleep (stage N3). Correlation analysis was used to evaluate the agreement on sleep parameters and attributing factors to the inaccuracies of the single-channel EEG recording.

Results

TST, sleep efficiency, REM sleep duration, and non-REM sleep duration of the single-channel EEG-based sleep monitoring showed a significant correlation with those of PSG. Lower sleep efficiency, a decrease in REM sleep, and increases in waking after sleep onset, arousal index, and apnea/hypopnea index were associated with the difference of sleep parameters between the two methods.

Conclusion

Among patients with psychiatric disorders who are sensitive to environmental change single-channel EEG sleep monitoring would be a useful technique to objectively evaluate sleep quality.

Support

Collaboration study with The KAITEKI Institute, Inc.

Maternal dietary patterns during early pregnancy and birth weight in Japan

Background

The average birth weight in Japan has decreased by 200 g in the last 40 years. Only three studies were reported for the association between maternal dietary patterns and birth weight in East Asia, whose results were inconsistent. We examined what maternal dietary patterns were associated with the birth weight in Japan.

Methods

Totally 22,493 pregnant women were recruited between July 2013 and September 2016 into the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. We included 17,287 women who had a full-term single healthy baby into the analysis. Consumption of food and beverage items was evaluated based on food frequency questionnaire at the first-trimester. Dietary patterns were analyzed using a machine learning method of k-means clustering algorithm. Birth weight was obtained from the medical record. The association between dietary patterns and birth weight was analyzed using multiple liner regression model adjusted for potential confounders with multiple imputation method for missing values.

Results

Dietary patterns were classified into seven groups by cluster analysis: “high in rice (reference) (n = 8046)”, “middle in vegetables, beans, mushrooms, seaweeds and miso-soup (n = 4842)”, “high in fruits (n = 1176)”, “high in bread, dairy and alcohol (n = 1091)”, “high in meat and fish (n = 1049)”, “high in coffee, black tea, soft drinks and confections (high in coffee) (n = 585)”, and “high in vegetables, beans, mushrooms, seaweeds and miso-soup (n = 498)” groups. In multiple liner regression models, birth weight was 22.6 g (95%CI: 0.1 to 45.2 g) heavier in “high in fruits” group than in reference group and 39.4 g (95%CI: 8.6 to 70.3 g) lighter in “high in coffee” group than in reference group. The other groups were not statistically significant.

Conclusions

High consumption of fruits and high consumption of coffee, black tea, soft drinks and confections during early pregnancy were associated with increased and decreased birth weight, respectively.

Key messages

We found maternal dietary patterns during early pregnancy using a machine learning method of k-means clustering algorithm. We found maternal dietary patterns which associated with the birth weight in Japan.

Ion-production efficiency of a singly charged ion source developed toward a 11C irradiation facility for cancer therapy

The ion-production efficiency of a newly developed singly charged ion source (SCIS) has been investigated to discuss the possibility of it being used in an isotope separation on-line system that provides ¹¹C ions for heavy-ion cancer therapy with simultaneous verification of the irradiation field using positron emission tomography. The SCIS uses a low-energy hollow electron beam to produce singly charged carbon ions efficiently. To deliver sufficient ¹¹C ions to the treatment room from a limited amount of ¹¹C molecules, which are produced from a boron compound target and proton-beam irradiation via the ¹¹B(p,n)¹¹C reaction, the SCIS must have high ion-production efficiency. To realize this high efficiency, the SCIS was designed using a three-dimensional particle-in-cell code in previous work. With the fabricated SCIS, we performed experiments to measure the efficiency of producing CO₂ ⁺ ions from nonradioactive ¹²CO₂ molecules and C⁺ ions from nonradioactive ¹²CH₄ molecules. We found that the SCIS achieved efficiencies of ε_C⁺ =4×10^-3 (0.4%) for C⁺ production and ε_{CO2 ⁺} =0.107 (10.7%) for CO₂ ⁺ production.

Singly charged ion source designed using three-dimensional particle-in-cell method

A singly charged ion source (SCIS) has been designed using a newly developed three-dimensional particle-in-cell (PIC) code. The SCIS is to be used in an isotope separation on-line (ISOL) system that provides ¹¹C ions for heavy-ion cancer therapy with simultaneous verification of the dose distribution using positron emission tomography. The SCIS uses low-energy electron beams to produce singly charged carbon ions efficiently and maintain a high vacuum in the ISOL system. Because the SCIS has to realize a production efficiency of 1% if its carbon ions are to be used in the ISOL system, a suitable design for the SCIS was investigated by using the developed PIC code to study the beam trajectories of the electrons and extracted ions. The simulation results show that hollow electron beams are produced in the designed SCIS resulting in a high effective electron current. The results also predict that the designed SCIS would realize ion-production efficiencies (IPEs) of ε _SCIS ≃ 6.7% for C O 2 + production from CO₂ gas and ε _SCIS ≃ 0.1% for C⁺ production from CH₄ gas. Moreover, to examine the validity of the developed code and confirm that the SCIS was able to be designed appropriately, the space-charge-limited current of the electron gun and the total IPE obtained by adding the IPEs of each ion were compared between the experiment and the simulation.

The comparison of nasal surgery and CPAP on daytime sleepiness in patients with OSAS

OBJECTIVE

Residual sleepiness after continuous positive airway pressure (CPAP) is a critical problem in some patients with obstructive sleep apnea syndrome (OSAS). However, nasal surgery is likely to reduce daytime sleepiness and feelings of unrefreshed sleep. The aim of this study is to clarify the effects of nasal surgery and CPAP on daytime sleepiness.

METHODOLOGY

This is a retrospective and matched-case control study. The participants were consecutive 40 patients with OSAS who underwent nasal surgery (Surgery group) and 40 matched patients who were treated with CPAP (CPAP group).

RESULTS

In the Surgery group, although the nasal surgery did not decrease either apnea or hypopnea, it improved oxygenation, the quality of sleep. In the CPAP Group, the CPAP treatment reduced apnea and hypopnea, and improved oxygenation, quality of sleep. The degree of relief from daytime sleepiness was different between the two groups. The improvement of Epworth Sleepiness Scale was more significant in the Surgery Group than those in the CPAP Group (Surgery from 11.0 to 5.1, CPAP from 10.0 to 6.2).

DISCUSSION

These findings suggest that the results of the nasal surgery is more satisfactory for some patients with OSAS than CPAP on daytime sleepiness.

Irradiation at Different Fetal Stages Results in Different Translocation Frequencies in Adult Mouse Thyroid Cells

While it is generally believed that fetuses are at high risk of developing cancers, including leukemia, after low doses of radiation, it has been reported that atomic bomb survivors exposed in utero did not show a dose response for translocations in blood T lymphocytes when they were examined at approximately 40 years of age. Subsequent mouse studies confirmed that animals irradiated during the fetal stage did not show evidence of radiation effects in lymphocytes and bone marrow cells when they were examined after reaching adulthood. However, in a study of rat mammary epithelial cells, radiation effects were clearly observed after fetal irradiation. These results indicate that the fate of chromosome aberrations induced in a fetus could vary among different tissues. Here we report on translocation frequencies in mouse thyroid cells, which were irradiated at different stages of fetal development. Cytogenetic examination was conducted using fluorescence n situ hybridization (FISH) painting of chromosomes 1 and 3. Adult mice, 2 Gy X-ray irradiated at 15.5-day-old fetuses (E15.5), showed a higher translocation frequency (30/1,155 or 25.3 × 10^-3) than nonirradiated adult controls (0/1,007 or 0.1 × 10^-3), and was near that experienced by irradiated mothers and non-pregnant adult females (43/1,244 or 33.7 × 10^-3). These results are consistent with those seen in rat mammary cells. However, when fetuses were irradiated at an earlier stage of development (E6.5) before thyroid organogenesis, the resulting observed translocation frequency was much lower (3/502 or 5.8 × 10^-3) than that in E15.5 mice. These results suggest that after fetal irradiation, tissue stem cells record radiation effects primarily when the exposure occurs in cells that have been integrated into tissue. Embryonic stem cells that have been damaged prior to integration into the niche may undergo negative selection due to apoptosis, mitotic death or stem cell-niche cell interactions. The implications of these results in interpreting cancer risks after fetal irradiation are also discussed.

A singly charged ion source for radioactive ¹¹C ion acceleration

A new singly charged ion source using electron impact ionization has been developed to realize an isotope separation on-line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive (11)C ion beams. Low-energy electron beams are used in the electron impact ion source to produce singly charged ions. Ionization efficiency was calculated in order to decide the geometric parameters of the ion source and to determine the required electron emission current for obtaining high ionization efficiency. Based on these considerations, the singly charged ion source was designed and fabricated. In testing, the fabricated ion source was found to have favorable performance as a singly charged ion source.

Cryogenic molecular separation system for radioactive (11)C ion acceleration

A (11)C molecular production/separation system (CMPS) has been developed as part of an isotope separation on line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive (11)C ion beams. In the ISOL system, (11)CH4 molecules will be produced by proton irradiation and separated from residual air impurities and impurities produced during the irradiation. The CMPS includes two cryogenic traps to separate specific molecules selectively from impurities by using vapor pressure differences among the molecular species. To investigate the fundamental performance of the CMPS, we performed separation experiments with non-radioactive (12)CH4 gases, which can simulate the chemical characteristics of (11)CH4 gases. We investigated the separation of CH4 molecules from impurities, which will be present as residual gases and are expected to be difficult to separate because the vapor pressure of air molecules is close to that of CH4. We determined the collection/separation efficiencies of the CMPS for various amounts of air impurities and found desirable operating conditions for the CMPS to be used as a molecular separation device in our ISOL system.

Direct heating of a laser-imploded core by ultraintense laser-driven ions

A novel direct core heating fusion process is introduced, in which a preimploded core is predominantly heated by energetic ions driven by LFEX, an extremely energetic ultrashort pulse laser. Consequently, we have observed the D(d,n)^{3}He-reacted neutrons (DD beam-fusion neutrons) with the yield of 5×10^{8} n/4π sr. Examination of the beam-fusion neutrons verified that the ions directly collide with the core plasma. While the hot electrons heat the whole core volume, the energetic ions deposit their energies locally in the core, forming hot spots for fuel ignition. As evidenced in the spectrum, the process simultaneously excited thermal neutrons with the yield of 6×10^{7} n/4π sr, raising the local core temperature from 0.8 to 1.8 keV. A one-dimensional hydrocode STAR 1D explains the shell implosion dynamics including the beam fusion and thermal fusion initiated by fast deuterons and carbon ions. A two-dimensional collisional particle-in-cell code predicts the core heating due to resistive processes driven by hot electrons, and also the generation of fast ions, which could be an additional heating source when they reach the core. Since the core density is limited to 2 g/cm^{3} in the current experiment, neither hot electrons nor fast ions can efficiently deposit their energy and the neutron yield remains low. In future work, we will achieve the higher core density (>10 g/cm^{3}); then hot electrons could contribute more to the core heating via drag heating. Together with hot electrons, the ion contribution to fast ignition is indispensable for realizing high-gain fusion. By virtue of its core heating and ignition, the proposed scheme can potentially achieve high gain fusion.

Status of a compact electron cyclotron resonance ion source for National Institute of Radiological Sciences-930 cyclotron

The Kei-source is a compact electron cyclotron resonance ion source using only permanent magnets and a frequency of 10 GHz. It was developed at the National Institute of Radiological Sciences (NIRS) for producing C(4+) ions oriented for high-energy carbon therapy. It has also been used as an ion source for the NIRS-930 cyclotron. Its microwave band region for the traveling-wave-tube amplifier and maximum output power are 8-10 GHz and 350 W, respectively. Since 2006, it has provided various ion beams such as proton, deuteron, carbon, oxygen, and neon with sufficient intensity (200 μA for proton and deuteron, 50 μA for C(4+), for example) and good stability for radioisotope production, tests of radiation damage, and basic research experiments. Its horizontal and vertical emittances were measured using a screen monitor and waist-scan. The present paper reports the current status of the Kei-source.