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Author(s): Yuta Inoki [sup.1] , Kentaro Nishi [sup.1] , Kei Osaka [sup.1] , Tomoya Kaneda [sup.1] , Misaki Akiyama [sup.1] , Mai Sato [sup.1] , Masao Ogura [sup.1] , Koichi [...], Background Patients on peritoneal dialysis (PD) may develop PD-related complications that necessitate abdominal surgery. However, when to resume PD and how to prescribe PD fluid after surgery in pediatric patients are unknown. Methods Patients on PD who underwent small-incision abdominal surgery between May 2006 and October 2021 were included in this retrospective observational study. The complications after surgery and characteristics of patients with PD fluid leakage were analyzed. Results Thirty-four patients were included. They underwent 45 surgical procedures, including 23 inguinal hernia repairs, 17 PD catheter repositioning or omentectomy, and 5 others. The median time to resume PD was 1.0 (IQR, 1.0-3.0) days, and the median PD exchange volume at the initiation of PD after surgery was 25 (IQR, 20-30) ml/kg/cycle. PD-related peritonitis occurred in two patients after omentectomy and one after inguinal hernia repair. There was no PD fluid leakage or hernia recurrence among the 22 patients who had a hernia repair. Peritoneal leakage occurred in 3 of the 17 patients who had PD catheter repositioning or an omentectomy and was treated conservatively. No patients who resumed PD 3 days after small-incision abdominal surgery with less than half of PD volume had fluid leakage. Conclusions Our findings demonstrated that PD could be resumed within 48 h of inguinal hernia repair with no PD fluid leakage or hernia recurrence in pediatric patients. In addition, resuming PD 3 days after a laparoscopic procedure with less than half of the usual dialysate volume might reduce the risk of PD fluid leakage. Graphical abstract

Without stereogenic carbon centers, organic molecules can be chiral when they have large energy barriers for conformational inversion. In this work, conformational behaviors are investigated for a series of tricyclic propellane skeletons with increasing 6‐membered‐ring peripheral moieties fused with aromatic rings. According to theoretical calculations, trinaphtho[3.3.3]propellane has three vertical naphthalene rings like triptycene shape without torsion along the central C−C single bond. On the other hand, hexabenzo[4.4.4]propellane shows hexaphenylethane‐like ca. 60° twist along the bond with large activation energy of 64 kcal mol−1 for twist inversion because of the high congestion caused by three 6‐membered‐ring loops. Indeed, the [4.4.4]propellane gives a stable pair of chiroptical enantiomers toward heating at 146 °C. By contrast, a hybrid [4.3.3]propellane exhibits fast interconversion between two twisted conformations even at −80 °C. [ABSTRACT FROM AUTHOR]

Pillar[5]arene is a promising macrocyclic receptor of a chemical sensor showing shape-selective encapsulation of neutral molecules into the cavity, but the poor fluorescence properties remain a challenge. Herein, we report a pillar[5]arene coupled with 2-(2-hydroxyphenyl)benzoxazole (HBO), which displays bright fluorescence in both solution and the solid state. Owing to the excited-state intramolecular proton transfer (ESIPT) in the HBO moiety, greatly improved fluorescence is observed for the pillar[5]arene derivative in CHCl3 (Φ lum = 11%) and powder form (Φ lum = 25%). Moreover, the emission color changes from light green to blue when the powder sample is exposed to n -hexane vapor. The color change derives from variable dual emission via ESIPT and excimer-forming pathways, as suggested by fluorescence lifetime measurements at different wavelengths. Powder x-ray diffraction indicates that increased crystallinity and a small alteration in the solid-state structure leads to visible fluorescent chromism upon vapor encapsulation. [ABSTRACT FROM AUTHOR]

The present study aimed to summarize and report data on errors related to treatment planning, which were collected by medical physicists. The following analyses were performed based on the 10-year error report data: (1) listing of high-risk errors that occurred and (2) the relationship between the number of treatments and error rates, (3) usefulness of the Automated Plan Checking System (APCS) with the Eclipse Scripting Application Programming Interface and (4) the relationship between human factors and error rates. Differences in error rates were observed before and after the use of APCS. APCS reduced the error rate by ~1% for high-risk errors and 3% for low-risk errors. The number of treatments was negatively correlated with error rates. Therefore, we examined the relationship between the workload of medical physicists and error occurrence and revealed that a very large workload may contribute to overlooking errors. Meanwhile, an increase in the number of medical physicists may lead to the detection of more errors. The number of errors was correlated with the number of physicians with less clinical experience; the error rates were higher when there were more physicians with less experience. This is likely due to the lack of training among clinically inexperienced physicians. An environment to provide adequate training is important, as inexperience in clinical practice can easily and directly lead to the occurrence of errors. In any environment, the need for additional plan checkers is an essential factor for eliminating errors. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to clarify the dosimetric impact of the respiratory motion of the liver on stereotactic body radiation therapy (SBRT) for spine metastasis and examine the utility of introducing beam avoidance (beam‐off at specific gantry angles). Methods: A total of 112 consecutive patients who underwent SBRT for spine metastasis between 2018 and 2024 were examined. Overall, 15 patients who had lesions near the liver dome were included in this study. Retrospective treatment plans were generated using computed tomography (CT) images acquired during inhalation and exhalation to evaluate the dosimetric impact of respiratory motion of the liver. The dose difference (DD) and relative value (DD%) were evaluated using the dose‐volume histogram (DVH) metrics, planning target volume Dmax, D95%, spinal cord D0.035 cc, and esophagus D2.5 cc. The magnitude of the liver movements was evaluated based on differences of liver size Lave at the isocentric axial plane between the inspiratory and expiratory CT images. Results: The DD in almost all DVH metrics tended to increase when the liver moved away from the target during inhalation: For example, Mean ±$ \pm $ a standard deviation (SD) DD in PTV D95% for the treatment plan incorporating beam avoidance and those without beam avoidance was 0.5 ±$\pm$ 0.3 and 0.9 ±$ \pm $ 0.6 Gy, respectively. The spinal cord D0.035 cc for those shows 0.4 ±$ \pm $ 0.2 and 0.7 ±$ \pm $ 0.7 Gy, respectively. The treatment plans without beam avoidance also showed moderate or strong correlations between Lave and DD for almost all DVH metrics. No correlation was seen in the beam avoidance plan. The spinal cord D0.035 cc revealed approximately 1 Gy or +4% in DD when Lave was < −4 cm. Conclusions: Respiratory motion of the liver dome can cause substantial dosimetric discrepancies in the dose delivered to the spinal cord, although the extent depends on patient variables. Dose assessment should be performed for determining the appropriate means of respiratory management, such as breath‐hold. Alternatively, beam avoidance effectively mitigates the impact. [ABSTRACT FROM AUTHOR]

Solid‐state assembling modes are as crucial as the chemical structures of single molecules for real applications. In this work, solid‐state structures and phase‐transition temperatures are investigated for a series of fluoranthene‐fused [3.3.3]propellanes consisting of a rigid three‐dimensional (3D) π‐core and varying lengths of alkoxy groups. Compounds in this series with n‐butoxy or longer alkoxy groups take an amorphous state at room temperature. In these molecules, rotatable biaryl‐type bonds are not incorporated and high D3h molecular symmetry is retained. Therefore, π‐fused [3.3.3]propellanes present a unique platform for amorphous molecular materials with low ratios of flexible alkoxy atoms to rigid π‐core ones. [ABSTRACT FROM AUTHOR]

Introduction: Scalp angiosarcoma is a rare and aggressive cancer. Definitive radiotherapy is a treatment option for localised scalp angiosarcoma patients. Although definitive surgical resection reportedly prolongs overall survival (OS), whether initial local treatment effect affects OS when definitive radiotherapy is administered is unclear. Therefore, this study analysed whether local recurrence within 6 months of irradiation correlates with OS and cancer‐specific survival (CSS). Furthermore, how local control affects patients' quality of life was investigated. Materials and methods: Thirty‐one localised scalp angiosarcoma patients who had received definitive radiotherapy at our institution between October 2010 and July 2021 were analysed retrospectively. The most commonly used dose fractionation was 70 Gy in 35 fractions (83.9%). Local recurrence within 6 months of radiotherapy and other clinical factors were examined in univariate and subsequent multivariate analyses for correlation with OS and CSS. Results: The median follow‐up period was 16 months (range, 6–45 months). Local recurrence was detected in 16 patients (51.6%), 12 of whom had recurrence within 6 months. In multivariate analyses, the presence of local recurrence within 6 months of radiotherapy was significantly associated with OS and CSS (p = 0.003, 0.0001, respectively). Ten of the 16 patients with local recurrence had severe symptoms such as bleeding, pain, difficulty opening the eye and malodour. Conclusions: The initial local treatment effect was significantly associated with OS and CSS after definitive radiotherapy. Furthermore, local recurrence after radiotherapy resulted in a variety of symptoms, including bleeding and pain, which reduced the patient's quality of life. [ABSTRACT FROM AUTHOR]