Tokai Gakuen University

The 3 factors of the classic model (maximal oxygen uptake [V·O2max], fractional utilization of V·O2max at the anaerobic threshold, and running economy [RE]) are well known to be the determinants of isolated distance running performance. However, no previous studies appear to have investigated the relationship between all 3 factors and running performance in the Olympic-distance triathlon (ODT). We therefore investigated this relationship by conducting 2 studies. In study I, the relationship between the 3 factors of the classic model and running performance in actual ODT races was investigated in 16 male triathletes. In study II, the relationship between the three factors and running performance in simulated ODT races with controlled exercise intensities, pedaling cadence, and carbohydrate intake during the swim and bike legs was investigated in 8 male triathletes. The 3 factors were quantified using a treadmill incremental test following the same protocol in each study. Simple correlation and multiple regression analyses were performed using the forced entry method. The independent variables were the 3 factors of the classic model, and the dependent variable was running performance in the ODT races. In study I, no significant correlation was found between the 2 measurements (p > 0.05). Furthermore, no significant multiple correlation coefficient was obtained (R < 0.54, p > 0.05), and < 10.7% of the running performance was attributable to the 3 factors. In study II, by contrast, a significant correlation was found between RE and running performance (r = 0.79, p = 0.02). In addition, a significant multiple correlation coefficient was obtained (R = 0.91, p = 0.05), and 69.9% of the running performance in the simulated ODT race was attributable to the three factors. In conclusion, we suggest that in the ODT the 3 factors of the classic model explain interindividual variation in running performance. However, in an actual ODT race, the relationship between the 3 factors and running performance may weaken owing to the residual effects of prior swimming and cycling.

Recent advances in PET image reconstruction have focused on achieving high image quality and quantitative accuracy. Bayesian penalized likelihood (BPL) algorithms, such as Q.Clear and HYPER Iterative that have been integrated into commercial PET systems offer robust image noise suppression and edge preservation through regularization. In parallel, methods based on deep learning such as SubtlePET, AiCE, uAI® HYPER DLR, and Precision DL have emerged primarily as post-processing techniques. They use trained convolutional neural networks to reduce image noise while preserving lesion contrast. These methods have reduced image acquisition times or reduced radiotracer doses while maintaining diagnostic confidence. uAI® HYPER DPR represents a hybrid approach by embedding deep learning in iterative reconstruction. This review summarizes the technical principles and the clinical performance of BPL and deep learning-based PET reconstruction algorithms, and discusses key considerations such as image quality and quantitative accuracy of PET images. This review should deepen understanding of advanced PET image reconstruction techniques and accelerate their clinical implementation across diverse PET imaging applications.

Carbon-ion radiotherapy (CIRT) is known as a promising treatment for liver tumors. However, no method has been established for estimating post-therapeutic residual liver reserve capacity (pRLRC). We previously introduced the estimation method of pRLRC using 99 mTc-galactosyl human serum albumin (99 mTc-GSA) scintigraphy (Yamazaki method). In this study, we developed "Yamazaki-variant" method for pRLRC using dose distribution data of CIRT planning. The purpose of this study was to compare pRLRC calculated by Yamazaki method and Yamazaki-variant in CIRT patients for liver tumors, and to provide the clinical advantages in both methods in terms of estimating ability of pRLRC. Patients who received CIRT for liver tumors in our hospital and underwent 99 mTc-GSA scintigraphy before and 3months after CIRT, and contrast-enhanced liver MRI within 1month before CIRT were included. A total of 71 patients, 21 additional to the 50 previously reported, were evaluated. The maximal removal rate of 99 mTc-GSA (GSA-Rmax) was analyzed and the GSA-Rmax of the estimated residual liver (GSA-RL) was calculated using fusion images of MRI and SPECT by Yamazaki method. In Yamazaki-variant, multiple simulations were performed using the dose distribution of the CIRT planning and SPECT fusion images to obtain higher diagnostic accuracy of GSA-RL. Two of these estimates, Validation 1 and Validation 2 by Yamazaki-variant, were used as validation data. GSA-RL and Validation 1 and 2 were compared with GSA-Rmax 3months after CIRT (post-GSA-Rmax) using linear regression analysis. GSA-RL, Validation 1 and 2 were calculated as 0.448 ± 0.214, 0.413 ± 0.199 and 0.435 ± 0.208 mg/min, respectively. Post-GSA-Rmax was 0.428 ± 0.220 mg/min. The relationship between post-GSA-Rmax and each parameter was y = 0.02 + 0.90x (R2 = 0.78) for GSA-RL, y = 0.02 + 0.94x (R2 = 0.79) for Estimation 1, y = 0.02 + 0.99x (R2 = 0.80) for Estimation 2, respectively (P <.0001). Both Yamazaki method and Yamazaki-variant showed comparable accurate estimation ability for post-GSA-Rmax. The estimation of pRLRC by Yamazaki method and Yamazaki-variant was in good agreement with post-therapeutic liver reserve capacity after CIRT, and there was no difference in the accuracy of the estimation. The usefulness of Yamazaki method, which is simpler and more clinically applicable, was confirmed. This study is registered in UMIN Clinical Trials Registry (UMIN-CTR) as UMIN study ID: UMIN000038328 and UMIN000049770, UMIN000038174.

IntroductionThis study aimed to determine the association between cumulative maternal physical activity level and their children’s physical activity in early childhood. We also compared the influence of each maternal physical activity on children’s physical activity in early childhood.MethodsWe analyzed the data from 1,067 Japanese mother-child pairs. Maternal physical activity was assessed using the International Physical Activity Questionnaire. Cumulative physical activity level in mothers was computed based on the categories (low, moderate, and high) of physical activity from five time points (pre-pregnancy, during pregnancy, 1.5, 3.5, and 5.5 years postpartum). Children’s physical activity level was measured at age 5.5 years using the WHO Health Behaviour School-aged Children questionnaire and defined as engaging in physical activity for at least 60 minutes per day for more than 5 days. Logistic regression analysis was used to determine the association between maternal and children’s physical activity levels.ResultsThe results showed the positive association between cumulative maternal physical activity and children’s physical activity level (P for trend < 0.001). Furthermore, maternal physical activity during pregnancy (P for trend = 0.031) and 5.5 years postpartum (P for trend < 0.001) was positively associated with children’s physical activity.ConclusionA positive association was observed between the cumulative maternal physical activity level and the physical activity level of their children at 5.5 years of age. Furthermore, maternal physical activity during pregnancy and at 5.5 years postpartum were positively associated with the level of children’s physical activity.

Abstract Cytochalasin D (CytoD) is widely used to inhibit actin polymerization, but the underlying regulatory mechanism is unclear. We addressed this using Total Internal Reflection Fluorescence (TIRF) microscopy. Our time course depolymerization assay of individual actin filaments showed that CytoD tightly caps the barbed end, with an estimated K m value for inhibition of 4.1 nM and a duration time of ∼1 min. Consistently, in polymerization assays, CytoD at concentrations near the K m value completely suppressed barbed end elongation. Interestingly, at lower concentrations, CytoD acted as a leaky capper, allowing actin monomer addition by rapidly binding to and dissociating from barbed ends. We interpreted this contradictory behavior as arising from differences in binding modes: capping one strand (fast dissociation) or both strands (slow dissociation). CytoD severs actin filaments at micromolar levels, a concentration range commonly used in cell biological studies. Although the severing rate is slower than cofilin, the frequency is higher, resulting in the fragmentation of filaments into shorter pieces. Severing activity was suppressed by inorganic phosphate or cofilin. We determined the crystal structure of CytoD bound to filamentous conformation (F-form) actin and found that CytoD fits better in the hydrophobic cleft of F-form actin than in the monomeric conformation actin, explaining the preferential binding towards barbed end subunits. The structure further indicates that CytoD prevents barbed end depolymerization by stabilizing the terminal subunits in the F-form, which is supported by our MD simulations. Collectively, our results demonstrate how CytoD regulates actin dynamics at the molecular level.

It is important to clarify the factors that cause errors when calculating nutrient and food group intake using dietary surveys. This study aimed to clarify the characteristics of errors in nutrient and food group intake among those who ate out and those who consumed ready-made meals when they recorded their meals using photographic and weighing methods. In October 2020, 38 second- and third-year students who were enrolled in dietitian training programs at two Japanese universities were asked to record their meals using both photographic and weighed records. Nutrient calculations were performed from the dietary records of both methods, and data from 29 subjects (all female) for whom 4-d dietary records were obtained were analyzed. The subjects were divided into two groups (high and low frequency of home-made meals) based on the median number of home-made meals, and a correlation analysis of the nutritional calculations obtained using both methods was performed. The results showed that most nutrient and food group intake levels were correlated (Spearman's correlation coefficient r=0.6-0.9) for both the high and low frequency of home-made meals. However, no correlation was found for "seasonings and spices" or their component "salt" in the low frequency of home-made meals group, indicating that there are errors in the nutritional calculations, especially for salt. It is thought that errors occurred for both the recorder and the nutrition calculator during the survey of meals eaten out; therefore, it is necessary to consider how to minimize errors before dietary surveys.

In order for teams to promote community-based management, it is essential for teams to exist as a public organization that revitalize of community.Given that place attachment was essential for the formation of communities, this study aim to clarify the effects of fan level and spectator satisfaction on place attachment was examined with the focus on difference of fans residences.Using a sample of fans ( n=229) , a hypothetical model was set up based on findings from previous studies and social identity theory and tested through structural equation modeling.Results revealed that fan level has a significant affected on service satisfaction and game satisfaction, and service satisfaction has a significant affected on place attachment.Significant indirect effects were also found in the effect of fan level on place attachment through service satisfaction.Furthermore, the results showed no significant differences in these effects between residences.

is study investigated the relationship between gambling addiction and the Dark Triad among Japanese adult gamblers. e study participants were 360 Japanese adult gamblers. ey were asked to complete an online questionnaire measuring their Dark Triad traits and the level or degree of their gambling addiction. e results showed that Machiavellianism and narcissism were correlated with gambling addiction among men, whereas psychopathy was correlated with gambling addiction among both men and women. ese results are partially consistent with those of previous studies conducted with Western samples.

We aimed to assess the effects of interaction between several breathing patterns and postures on abdominal muscle activation and intra-abdominal pressure (IAP). This comparative cross-sectional study enrolled fourteen healthy university students majoring in sports science and/or physical education. They performed four active breathing tasks: quiet nasal breathing (Q-Bre), nasal deep breathing (Deep-Bre), completely forced expiration (Forced-Expi), and exertional nasal inhalation with abdominal muscles with isometric contraction (Exertion-Inspi) in the elbow-toe plank and supine postures. Breathing volume; IAP; and transverse abdominis-internal oblique muscle (TrA-IO) and external oblique muscle (EO) activities were recorded. Abdominal muscle activity and IAP significantly interacted with breathing pattern and postures during the expiratory phase (p < 0.05). In the inspiratory phase, TrA-IO activity was significantly affected by breathing pattern and EO activity with posture (p < 0.05). TrA-IO activity significantly increased during Forced-Expi in the supine posture (47.6% of the maximum voluntary contraction) and Exertion-Inspi in the elbow-toe posture (35.7%), whereas no differences were found during Deep-Bre or Q-Bre (< 20%). EO activity increased in the elbow-toe posture (22.5–30.6%) compared with that in the supine posture (< 5%) during all breathing tasks. IAP values were low during all tasks (< 15%) except for Forced-Expi (24.9%). Abdominal muscle activation and IAP interacted with the breathing pattern and posture.