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Patient respiration is characterized by respiratory parameters, such as cycle, amplitude, and baseline drift. In treatment planning using four-dimensional computed tomography (4DCT) images, the target dose may be affected by variations in image reconstruction techniques and respiratory parameters. This study aimed to optimize 4DCT image reconstruction techniques for the treatment planning of lung stereotactic body radiotherapy (SBRT) based on respiratory parameters using respiratory motion phantom. We quantified respiratory parameters using 30 respiratory motion datasets. The 4DCT images were acquired, and the phase- and amplitude-based reconstruction images (RI) were created. The target dose was calculated based on these reconstructed images. Statistical analysis was performed using Pearson's correlation coefficient (r) to determine the relationship between respiratory parameters and target dose in each reconstructed technique and respiratory region. In the inhalation region of phase-based RI, r of the target dose and baseline drift was -0.52. In particular, the target dose was significantly reduced for respiratory parameters with a baseline drift of 0.8 mm/s and above. No other respiratory parameters or respiratory regions were significantly correlated with target dose in phase-based RI. In amplitude-based RI, there were no significant differences in the correlation between all respiratory parameters and target dose in the exhalation or inhalation regions. These results showed that the target dose of the amplitude-based RI did not depend on changes in respiratory parameters or respiratory regions, compared to the phase-based RI. However, it is possible to guarantee the target dose by considering respiratory parameters during the inhalation region of the phase-based RI., (© 2024. The Author(s), under exclusive licence to Japanese Society of Radiological Technology and Japan Society of Medical Physics.)

Background: We devised a method that combines the 3D-Dixon-gradientecho (GRE) method with an improved motion-sensitized driven-equilibrium (iMSDE) to suppress blood flow signals., Purpose: The purpose of this study was to evaluate the effectiveness of the new method we developed plaque imaging method (3D-Dixon-GRE with the iMSDE method)., Study Type: Retrospective cohort., Population: Thirty-nine patients who underwent cervical plaque imaging., Field Strength/sequence: 3.0 T/3D-GRE., Assessment: Signal intensities of the common carotid artery, aorta, plaque, muscle, and subcutaneous fat were measured through the VISTA and the 3D-Dixon-GRE with iMSDE methods, and each contrast was calculated., Statistical Test: Used the Mann Whitney U test. P-values below 0.05 were considered statistically significant., Results: Plaque and muscle contrast estimated through the VISTA method and 3D-Dixon-GRE with iMSDE method was 1.60 ± 0.96 and 2.04 ± 1.06, respectively, (P < 0.05). The contrast between the flow (common carotid artery and Aorta) and muscle according to the VISTA method and 3D-Dixon-GRE with iMSDE method was 0.24 ± 0.11 and 0.40 ± 0.12, respectively (P < 0.001). Finally, the mean contrast for subcutaneous fat and muscle at six locations was 3.05 ± 1.25 and 0.81 ± 0.23 for the VISTA method and 3D-Dixon-GRE with the iMSDE method, respectively (P < 0.001)., Data Conclusion: Compared to the conventional method (VISTA), the 3D-Dixon-GRE with iMSDE method is preferable in relation to the fat suppression effect, but it is disadvantageous regarding blood flow signal suppression. Therefore, the 3D-Dixon-GRE with the iMSDE method could be considered useful for plaque imaging., Competing Interests: Declaration of competing interest No conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Pv11 is the only animal cell line that, when preconditioned with a high concentration of trehalose, can be preserved in the dry state at room temperature for more than one year while retaining the ability to resume proliferation. This extreme desiccation tolerance is referred to as anhydrobiosis. Here, we identified a transporter that contributes to the recovery of Pv11 cells from anhydrobiosis. In general, the solute carrier 5 (SLC5)-type secondary active transporters cotransport Na + and carbohydrates including glucose. The heterologous expression systems showed that the transporter belonging to the SLC5 family, whose expression increases upon rehydration, exhibits Na + -dependent trehalose transport activity. Therefore, we named it STRT1 (sodium-ion trehalose transporter 1). We report an SLC5 family member that transports a naturally occurring disaccharide, such as trehalose. Knockout of the Strt1 gene significantly reduced the viability of Pv11 cells upon rehydration after desiccation. During rehydration, when intracellular trehalose is no longer needed, Strt1 -knockout cells released the disaccharide more slowly than the parental cell line. During rehydration, Pv11 cells became roughly spherical due to osmotic pressure changes, but then returned to their original spindle shape after about 30 min. Strt1 -knockout cells, however, required about 50 min to adopt their normal morphology. STRT1 probably regulates intracellular osmolality by releasing unwanted intracellular trehalose with Na + , thereby facilitating the recovery of normal cell morphology during rehydration. STRT1 likely improves the viability of dried Pv11 cells by rapidly alleviating the significant physical stresses that arise during rehydration., Competing Interests: Competing interests statement:The authors declare no competing interest.

In magnetic resonance imaging (MRI), it is necessary to reduce image distortion as much as possible because it suppresses the increase in the planning target volume. This study investigated the relationship between imaging parameters and image distortion when using G-frames. The images were obtained using a 1.5-T MRI system with a 09-101 Pro-MRI phantom. Image distortion was measured by changing the RF pulse mode, gradient mode, asymmetric echo, and bandwidth (BW). The image distortion was increased in the high RF mode than in the Normal mode. The image distortion increased in the following order: Whisper ≦ Normal < Fast in the different gradient modes. The image distortion increased in the following order: Without ≦ Weak < Strong in the different asymmetric echo modes. The image distortion increased in the following order: 300 Hz/pixel > 670 Hz/pixel ≧ REF (150 Hz/pixel) in the different Bw. The relationship between parameters and image distortion was clarified in this study when G-frames were used for gamma knife therapy. There is had relationship between the parameters causing variation in the gradient magnetic field and image distortion. Therefore, these parameters should be adjusted to minimize distortion., (© 2023 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine.)

Programmable liquid handling devices for cell culture systems have dramatically enhanced scalability and reproducibility. We previously reported a protocol to produce cell aggregates demonstrating growth plate-like structures containing hypertrophic chondrocytes from human induced pluripotent stem cells (hiPSCs). To apply this protocol to large-scale drug screening for growth plate-related diseases, we adapted it to the automated cell culture system (ACCS) consisting of programmable liquid handling devices connected to CO 2 incubators, a refrigerator, and labware feeders, designed for up to 4 batches with several cell culture plates culturing for several months. We developed a new program preparing culture media with growth factors at final concentration immediately before dispensing them to each well and precisely positioning the tip for the medium change without damaging cell aggregates. Using these programs on the ACCS, we successfully cultured cell aggregates for 56 days, only needing to replenish the labware, medium, and growth factors twice a week. The size of cell aggregates in each well increased over time, with low well-to-well variability. Cell aggregates on day 56 showed histochemical, immunohistochemical, and gene expression properties of growth plate-like structures containing hypertrophic chondrocytes, indicating proper quality as materials for basic research and drug discovery of growth plate related diseases. The established program will be a suitable reference for making programs of experiments requiring long term and complex culture procedures using ACCS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Pv11 was derived from embryos of the sleeping chironomid Polypedilum vanderplanki , which displays an extreme form of desiccation tolerance known as anhydrobiosis. Pre-treatment with a high concentration of trehalose allows Pv11 cells to enter anhydrobiosis. In the dry state, Pv11 cells preserve transgenic luciferase while retaining its activity. Thus, these cells could be utilized for dry-preserving antibodies, enzymes, signaling proteins or other valuable biological materials without denaturation. However, Pv11 cells grow in suspension, which limits their applicability; for instance, they cannot be integrated into microfluidic devices or used in devices such as sensor chips. Therefore, in this paper, we developed an effective immobilization system for Pv11 cells that, crucially, allows them to maintain their anhydrobiotic potential even when immobilized. Pv11 cells exhibited a very high adhesion rate with both biocompatible anchor for membrane (BAM) and Cell-Tak coatings, which have been reported to be effective on other cultured cells. We also found that Pv11 cells immobilized well to uncoated glass if handled in serum-free medium. Interestingly, Pv11 cells showed desiccation tolerance when trehalose treatment was done prior to immobilization of the cells. In contrast, trehalose treatment after immobilization of Pv11 cells resulted in a significant decrease in desiccation tolerance. Thus, it is important to induce anhydrobiosis before immobilization. In summary, we report the successful development of a protocol for the dry preservation of immobilized Pv11 cells., Supplementary Information: The online version contains supplementary material available at 10.1007/s10616-023-00592-0., Competing Interests: Competing interestsThe authors declare no competing interest., (© The Author(s), under exclusive licence to Springer Nature B.V. 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Despite the dedicated research of artificial intelligence (AI) for pathological images, the construction of AI applicable to histopathological tissue subtypes, is limited by insufficient dataset collection owing to disease infrequency. Here, we present a solution involving the addition of supplemental tissue array (TA) images that are adjusted to the tonality of the main data using a cycle-consistent generative adversarial network (CycleGAN) to the training data for rare tissue types. F1 scores of rare tissue types that constitute < 1.2% of the training data were significantly increased by improving recall values after adding color-adjusted TA images constituting < 0.65% of total training patches. The detector also enabled the equivalent discrimination of clinical images from two distinct hospitals and the capability was more increased following color-correction of test data before AI identification (F1 score from 45.2 ± 27.1 to 77.1 ± 10.3, p < 0.01). These methods also classified intraoperative frozen sections, while excessive supplementation paradoxically decreased F1 scores. These results identify strategies for building an AI that preserves the imbalance between training data with large differences in actual disease frequencies, which is important for constructing AI for practical histopathological classification., (© 2023. The Author(s).)

This study aimed to investigate the effect of using slice partial Fourier (SPF), phase partial Fourier (PPF), and radial scan (Elliptical scanning) methods on image quality. Changes in signal-to-noise ratio (SNR), effective slice thickness, and in-plane resolution were measured in 3D-gradient echo when SPF, PPF, and radial scan were used. Effective slice thickness increased and SNR increased when SPF was used; in-plane resolution decreased and SNR decreased when PPF was used; effective slice thickness did not change, in-plane resolution decreased, and SNR increased when the radial scan method was used. The radial scan method reduces image quality and imaging time compared to those in the SPF and PPF methods., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Due to their physiological relevance, cell-based assays using human-induced pluripotent stem cell (iPSC)-derived cells are a promising in vitro pharmacological evaluation system for drug candidates. However, cell-based assays involve complex processes such as long-term culture, real-time and continuous observation of living cells, and detection of many cellular events. Automating multi-sample processing through these assays will enhance reproducibility by limiting human error and reduce researchers' valuable time spent conducting these experiments. Furthermore, this integration enables continuous tracking of morphological changes, which is not possible with the use of stand-alone devices. This report describes a new laboratory automation system called the Screening Station, which uses novel automation control and scheduling software called Green Button Go to integrate various devices. To integrate the above-mentioned processes, we established three workflows in Green Button Go: 1) For long-term cell culture, culture plates and medium containers are transported from the automatic CO 2 incubator and cool incubator, respectively, and the cell culture medium in the microplates is exchanged daily using the Biomek i7 workstation; 2) For time-lapse live-cell imaging, culture plates are automatically transferred between the CQ1 confocal quantitative image cytometer and the SCALE48W automatic CO 2 incubator; 3) For immunofluorescence imaging assays, in addition to the above-mentioned devices, the 405LS microplate washer allows for formalin-fixation and immunostaining of cells. By scheduling various combinations of the three workflows, we successfully automated the culture and medium exchange processes for iPSCs derived from patients with facioscapulohumeral muscular dystrophy, confirmation of their differentiation status by live-cell imaging, and confirmation of the presence of differentiation markers by immunostaining. In addition, deep learning analysis enabled us to quantify the degree of iPSC differentiation from live-cell imaging data. Further, the results of the fully automated experiments could be accessed via the intranet, enabling experiments and analysis to be conducted remotely once the necessary reagents and labware were prepared. We expect that the ability to perform clinically and physiologically relevant cell-based assays from remote locations using the Screening Station will facilitate global research collaboration and accelerate the discovery of new drug candidates., Competing Interests: Declaration of Competing Interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Purpose: To validate the point-A dose and dose distribution of metal and resin applicators in comparison with those of TG-43U1., Methods: The metal and resin applicators consisting of tandem and ovoid were modeled by the egs&#95;brachy. The doses to point A and dose distributions considering each applicator were calculated and compared to those of TG-43U1., Results: The dose to point A considering the metal applicator was 3.2% lower than that of TG-43U1, but there was no difference in the dose to point A considering the resin applicator. The dose distribution considering the metal applicator was lower than that of TG-43U1 at all calculation points, but there was no difference in the dose distribution considering the resin applicator at almost all calculation points., Conclusion: In this study, the dose distribution considering the metal applicator was lower than that of TG-43U1 at all calculation points, but there was no difference in the dose distribution considering the resin applicator at almost all calculation points. Therefore, TG-43U1 can accurately calculate the dose distribution when changing from the metal applicator to the resin applicator.

The aim of this study is to examine stone-event-free survival after ureteroscopic lithotripsy (URSL) and risk factors for stone events by age. We retrospectively collected data of all URSL cases at our institution from 2008 to 2021. A total of 1334 cases were included and divided into young (< 65 years, 792 cases), young-old (65-74 years, 316 cases), old-old (75-84 years, 172 cases), and oldest-old (≥ 85 years, 54 cases) groups. Patient characteristics, surgical outcomes, and postoperative stone events were evaluated. The stone-event-free survival and risk factors were compared between young and older groups. Overall, 214 (16.0%) cases developed stone events during a mean follow-up period of 763 days and the 2-year, 5-year, and 8-year stone-event-free survival rates were 84.5%, 72.2%, and 57.2%, respectively. The numbers of stone events in young, young-old, old-old, oldest-old groups were 133 (16.8%), 53 (16.8%), 21 (12.2%), and 7 (13.0%), respectively. No significant differences were found in stone-event-free survival between the young group and each of the older groups. Residual fragment > 4 mm and stone burden ≥ 15 mm were common risk factors in both young and older groups. Especially in older patients, preoperative stenting, which was most often performed to treat obstructive pyelonephritis, was the third risk factor. In conclusion, stone-event-free survival after URSL was comparable between young and older patients. Residual fragment > 4 mm and stone burden ≥ 15 mm were common risk factors in both groups. Preoperative stenting was an additional risk factor in older patients, suggesting that urinary tract infection may influence stone events., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To deal with the broad spectrum of coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), that threaten human health, it is essential to not only drugs develop that target viral proteins but also consider drugs that target host proteins/cellular processes to protect them from being hijacked for viral infection and replication. To this end, it has been reported that autophagy is deeply involved in coronavirus infection. In this study, we used airway organoids to screen a chemical library of autophagic modulators to identify compounds that could potentially be used to fight against infections by a broad range of coronaviruses. Among the 80 autophagy-related compounds tested, cycloheximide and thapsigargin reduced SARS-CoV-2 infection efficiency in a dose-dependent manner. Cycloheximide treatment reduced the infection efficiency of not only six SARS-CoV-2 variants but also human coronavirus (HCoV)-229E and HCoV-OC43. Cycloheximide treatment also reversed viral infection-induced innate immune responses. However, even low-dose (1 μM) cycloheximide treatment altered the expression profile of ribosomal RNAs; thus, side effects such as inhibition of protein synthesis in host cells must be considered. These results suggest that cycloheximide has broad-spectrum anti-coronavirus activity in vitro and warrants further investigation.

In this study, we developed a mouthpiece-type gel dosimeter to prevent the oral mucositis caused by the perturbation effect of dental alloys in the radiotherapy of the head and neck regions and to enable in vivo dosimetry. Understanding the dose distribution in the oral cavity during radiotherapy helps identify the possible site for oral mucositis during treatment. Here agarose, which has a higher melting point than gelatin, was added as a coagulant to stabilize the shape of the dosimeter. The strength and dose response of the dosimeter were investigated. The strength was measured at room temperature, 20°C-40 °C, which is higher than the intraoral temperature. The dose-response curves were obtained by magnetic resonance imaging with R 2 ranging from 0 to 25 Gy. The strength and dose response of the mouthpiece-type gel dosimeter were approximately 4 and 2.1 times higher than those of polyacrylamide gel and tetrakis hydroxymethyl phosphonium chloride dosimeters commonly used in the prescribed doses per fraction of treatment. The dosimeter is composed of 4 wt% MgCl 2 and 1.5 wt% agarose; thus, it can retain the water equivalence. Through in vivo oral dosimetry in three dimensions for head and neck radiotherapy with dental alloys using the mouthpiece-type gel dosimeter, we obtained three-dimensional dose distributions in the dosimeter. The properties of the dosimeter show that it can be used in the clinic, depending on the prescribed dose., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Purpose: The aim of this study was to compare the failure rates of insertion of a 10/12-Fr ureteral access sheath (UAS) during retrograde intrarenal surgery (RIRS) in cases with and without stones and to analyze the risk factors for UAS insertion failure., Materials and Methods: A total of 640 RIRS cases (538 with and 102 without stones) were evaluated. The primary outcome of interest was the failure rate of insertion of a 10/12-Fr UAS. Associated risk factors were assessed using univariate and multivariate logistic regression analyses. Propensity score (PS) matching and inverse probability of treatment weighting (IPTW) were used to ensure the robustness of the results., Results: The overall failure rate of 10/12-Fr UAS insertion in the cases without stones was significantly higher than that in the cases with stones (39.2% vs. 7.2%; p<0.001), and was approximately 2.5 to 4 times higher after PS matching and IPTW. Multivariate logistic analyses showed that being in the group without stones and younger age were independent significant risk factors for insertion failure in both the PS-matched cohort (odds ratio [OR], 5.43; 95% confidence interval [CI], 2.16-13.6; and OR, 1.04; 95% CI, 1.01-1.07) and the IPTW-adjusted cohort (OR, 1.82; 95% CI, 1.14-2.90; and OR, 1.03; 95% CI, 1.01-1.04)., Conclusions: The incidence of 10/12-Fr UAS insertion failure during RIRS was higher in cases without stones than in those with stones. These results provide valuable information for surgeons to use during informed consent discussions with patients undergoing RIRS, especially patients without stones., Competing Interests: The authors have nothing to disclose., (© The Korean Urological Association.)

This paper proposes a new concept of phantom development, along with the utilization of new materials that can reproduce lung morphology and density. A lung substitute phantom using microspheres was fabricated; then, its dosimetric utility in radiotherapy was investigated, during which the density was adjusted to closely resemble the morphology of the actual human lung. Microspheres were used to reproduce alveoli, which are the main components of the lung. By changing the ratio of urethane, which is commonly used in soft tissue phantoms, to microspheres, we reproduced the density change of the lungs due to respiration. Here, we fabricated two slab-like lung substitutes to emulate commercially used phantoms. Although there is room for improvement in terms of practicality, the substitutes were easy to fabricate. Microscopic observation of the cut surface of the phantoms showed that the morphology of the phantoms mimicked the alveoli more faithfully than commercial phantoms. Furthermore, to compensate for the energy-independent mass attenuation and mass collision inhibition ability required by the tissue substitute phantom, we examined the physical properties of the phantom and confirmed that there was negligible energy dependence.

Objective: Difficult ureter can be a challenge for accessing upper urinary tract during lithotripsy. In this study, we evaluated the risk factors for the incidence of difficult ureter in retrograde ureteroscopic lithotripsy. Moreover, we aimed to develop a predictive model for the incidence of difficult ureter., Methods: We retrospectively reviewed consecutive retrograde ureteroscopic lithotripsies performed at our institution between 2009 and 2021. A total of 1010 renal units were evaluated: 449 units with renal stones only and 561 units with ureteral stones, with or without renal stones., Results: The overall incidence of difficult ureter was 5.9%, with a higher incidence in the renal alone stone group than in the ureteral stone group (7.8% vs 4.5%, P = 0.026). Multivariate regression analysis revealed three risk factors for the incidence of difficult ureter: absence of stone history (odds ratio 5.67, 95% confidence interval 2.40-13.4, and P < 0.001), age ≤45 years (odds ratio 3.61, 95% confidence interval 2.05-6.37, and P < 0.001), and renal stone only (odds ratio 2.11, 95% confidence interval 1.22-3.64, and P = 0.008). A simple model using these three risks enabled the stratification of the incidence rate of difficult ureter, with the incidence of high-risk cases being 12.7%., Conclusions: The greatest risk factor for the incidence of difficult ureter was the absence of stone history, followed by age 45 years or younger, and having only renal stones. In high-risk cases of difficult ureter, the possibility of secondary lithotripsy should be explained to the patients., (© 2022 The Japanese Urological Association.)