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We carried out an experiment to produce the neutron-rich hypernucleus Λ6H via the (π−, K+) reaction on 6Li target at the pion beam momentum of 1.2 GeV/c (J-PARC E10). In order to calibrate the scale of the missing-mass or of the Λ binding energy of the hypernucleus, we also measured the 12C(π+, K+) Λ12C, p(π−, K+)Σ− and p(π+, K+)Σ+reactions. The experiment was performed at the J-PARC Hadron Hall K1.8 beam line in December 2012 and January 2013. The overall collected data sample corresponds to an integrated beam intensity of 1.65 × 1012 pions.

Molecular subtyping in gastrointestinal stromal tumours is a useful method for predicting the efficacy of treatment using tyrosine kinase inhibitors in humans. However, owing to the paucity of reports on mutational analyses, the association between genetic mutations and the therapeutic response to tyrosine kinase inhibitors remains unclear in feline gastrointestinal stromal tumours. In this report, we describe the case of a cat with a gastrointestinal stromal tumour which was unresponsive to tyrosine kinase inhibitors. A mutational analysis revealed that the cat lacked mutations in both the KIT and platelet‐derived growth factor receptor‐alpha (PDGFRA) genes. Our findings are consistent with the fact that KIT/PDGFRA wild‐type gastrointestinal stromal tumours are less responsive to tyrosine kinase inhibitors in humans. This signifies the need for further evaluation and possibly individualised treatment for gastrointestinal stromal tumours in cats on the basis of mutational analyses. [ABSTRACT FROM AUTHOR]

Objective: To determine the feasibility of three‐dimensional conformal radiation therapy for canine aortic body tumours. Materials and Methods: Medical records of dogs that had undergone three‐dimensional conformal radiation therapy with presumptive diagnosis of aortic body tumour were reviewed for clinical characteristics, treatment modality and outcomes. Results: Eight dogs were diagnosed with aortic body tumour and were treated with three‐dimensional conformal radiation therapy. One dog had proliferation of a mass in the right atrium during treatment and died of respiratory distress. Another dog did not undergo follow‐up CT to evaluate the treatment response due to the increased blood urea nitrogen values. The remaining 6 dogs were included in the case series. Radiotherapy was performed using a median dose per fraction of 7 Gy (3.3‐7.14 Gy), a median of seven divided doses (7‐15) and a total median dose of 49 Gy (45‐50 Gy). The median number of CT scans during the follow‐up period was 5 (range: 3‐8 times). CT revealed acute side effects in four dogs—grade 1 effects related to the lung (n = 4) and skin (n = 2). Self‐limiting or asymptomatic late side effects (grade 1 lung‐related effect) were observed in three dogs. After therapy, one dog demonstrated a complete response, another demonstrated a partial response and the disease remained stable in four animals. The median follow‐up period was 514.5 (235‐1219) days. After three‐dimensional conformal radiation therapy, the aortic body tumour reduced gradually over time without regrowth in all these 6 dogs. Clinical Significance: In this small case series, aortic body tumours responded to three‐dimensional conformal radiation therapy. Transient and self‐limiting side effects of the treatments were common. Further controlled studies are required to prove the effectiveness and the safety of this intervention. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To evaluate the activity and tolerability of three-dimensional conformal radiation therapy (3D-CRT) in dogs with massive hepatocellular carcinoma. MATERIALS AND METHODS: Six dogs with massive hepatocellular carcinoma that were ineligible for surgical resection or with owners who declined surgical resection, and underwent 3D-CRT were retrospectively reviewed. 6 to 10 Gy per fraction was prescribed at isocentre of planning target volume to a total dose of 18 to 42 Gy with 1 to 2 fractions per week for a total of 3 to 7 fractions. Follow-up examinations included physical examination, contrast-enhanced CT scan and blood analysis (complete blood count, electrolytes and serum biochemical panel). RESULTS: The median follow-up time after 3D-CRT was 534 (range, 281 to 1057) days. An objective response was observed in five of six cases. Radiation-induced liver disease developed in one dog but was asymptomatic and reversible. Toxicity was not noted in any other dog. CLINICAL SIGNIFICANCE: 3D-CRT appears to be a viable treatment option for dogs with inoperable massive hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

This paper presents the experimental results of high-speed tests using PVB sheets and PVB laminated glass. PVB showed a non-linear visco-elastic property in the low-speed tests. The non-linear visco-elastic property could be described using a simple spring-dashpot model including a non-linear spring. The visco-elastic parameters were determined by comparing the experimentally obtained stress-strain curves to the simulated model in which the various visco-elastic parameters are used. The strain-stress curves of PVB under high strain rates are elasto-plastic and those under the low strain rates are non-linear visco-elastic. The phenomenon can be explained from the phase transition from rubbery phase to glassy phase. Considering the results of PVB tensile tests, a simple fracture-mechanical model of PVB laminated glass was formulated to determine energy release rate G. Fracture toughness GC of the PVB laminated glass specimens were calculated from both the experimental results and the energy release rate. Potential energy UC was defined and also compared to the fracture toughness. Nevertheless, the critical loads increase with respect to the increase of tensile speed; potential energy and the fracture toughness remain the same order in all of the chosen tensile speeds. [ABSTRACT FROM AUTHOR]

Although lymphoscintigraphy is a useful method of detecting the sentinel nodes of malignancy, conventional lymphoscintigraphy images only the sentinel nodes without revealing their anatomical location. We, therefore, used scattered photons to attempt to outline the body contours of patients with either breast or esophageal cancer. Lymphoscintigraphy was performed 3 to 4 hours after the injection of 111 MBq of 99mTc tin colloid into the peritumoral region. Images were obtained with dual-energy windows of 130 to 150 keV for the primary photons and 70 to 110 keV for the scattered photons. The images constructed from the scattered photons clearly showed the contours of the body, and the fusion images constructed from the primary and scattered photons allowed for easy identification of the location of the sentinel nodes. The results of this study confirm that images obtained from scattered photons on lymphoscintigraphy are helpful in identifying the anatomical location of sentinel nodes. [ABSTRACT FROM AUTHOR]

The article describes the use of the videolaryngoscope, the Airway Scope (AWS), for intubation during caesarean section, done under regional anaesthesia, with patients suffering from massive intraoperative postpartum haemorrhage. Two pregnant women were intubated with minimal local anaesthesia so as to prevent cardiovascular compromise. It is believed that the AWS is useful for anaesthetic procedures in the parturient with haemo-dynamic instability due to massive haemorrhage.

At the Hadron Experimental Facility in J-PARC, we inject a 30-GeV proton beam into a gold target to produce secondary particle beams required for various particle and nuclear physics experiments. The gold target is placed in a hermetic chamber, and helium gas is circulated in the chamber to monitor the soundness of the target. The radioactivity in helium gas is continuously monitored by gamma-ray detectors such as a germanium detector and a NaI(Tl) detector. Beam operations with those target-monitoring systems were successfully performed from April to June and October to December 2015, and from May to June 2016. In this paper, the details of the helium gas circulation system and gamma-ray detectors and the analysis results of the obtained gamma-ray spectra are reported.

An accurate and non-invasive assessment of tumor response following treatment is essential. Traditional anatomical imaging techniques are insufficient before a significant morphological change can be observed. Metabolic imaging of molecular processes in the living body is also used. In recent years, deuterium magnetic resonance spectroscopic (MRS) imaging has been demonstrated as an alternative for cancer metabolic imaging by high-field (4–11T) MRI using deuterium-labeled molecules as a contrast agent. The study aim was to evaluate the feasibility of using deuterium MRI 1.5T for tumor visualization and early assessment of the efficacy of three anticancer treatment strategies (radiation and anticancer drugs) in pancreatic cancer model mice given heavy water (D 2 O) to induce deuterium (2H)-tissue labeling. A MIA PaCa-2 pancreatic cancer model of six BALB/c-nu mice was prepared, and repeated deuterium MRI was performed during the first 10 days after starting free drinking of 30% D 2 O. We also evaluated 2H accumulation in the tumor after irradiation, bevacizumab administration, or gemcitabine administration of other 20 mice. Additional confirmatory proton MRI, ex vivo metabolic hyperpolarization 13C-MRS and histopathology were performed. The mouse's whole-body distribution of 2H was visible 1 day after drinking, and the signal intensity increased daily. Although the tumor size did not change 1 and 3 days after irradiation, the amount of 2H in the tumor decreased significantly. The 2H image intensity of the tumor also significantly decreased after the administration of bevacizumab or gemcitabine. Metabolic hyperpolarization 13C-MRS, proton MRI and 2H-NMR spectroscopy confirmed the efficacy of the anticancer treatments. Deuterium MRI at 1.5T proved feasibility to track 2H distribution throughout mouse tissues during D 2 O administration and revealed a higher 2H accumulation in the tumor xenografts. This research demonstrated a promising successful method for early assessment of radiotherapy and chemotherapy of pancreatic cancer. [ABSTRACT FROM AUTHOR]

Visualization of radiation dose and tracks enable even safer and more accurate radiation therapy. It is already known that free radicals are generated by irradiation and imaging these free radicals will lead to an accurate understanding of the treatment dose and area after radiation therapy. We have been developing the free radical imaging methods using Dynamic Nuclear Polarization (DNP)-MRI with nitroxyl radicals as a redox probe (e.g., 1-Oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine (Tempol)). We previously demonstrated that the mixed solution of Tempol and glutathione (GSH) was useful as a probe for detecting free-radical reactions, allowing us to observe the redox reaction after irradiation clearly. However, one of the problems was that the stability of the solution was limited. In order to apply this technology in vivo, we considered it was necessary to improve its stability. In this study, we focused on 4-Methacryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempo methacrylate; TempoMC) as a new redox probe that is stable in GSH solution, and further improved the imaging method. To confirm the stability of TempoMC in various concentrations of GSH solutions, EPR signals were measured immediately after mixing and after 1 day, 3 days, and 7 days. The reduction of TempoMC by ascorbic acid (AsA) was monitored by X-band EPR spectroscopy to demonstrate the redox imaging capability. To confirm the possibility of redox reaction between TempoMC/GSH solution with free radicals induced by X-ray. The glass capillaries including TempoMC and GSH were irradiated 10 Gy by Linac, and the ESR signals were measured. Free radical imaging by low filed type of dynamic nuclear polarization (DNP)-MRI was performed using phantom filled with TempoMC and GSH solution. In contrast to Tempol, which showed a sharp EPR signal decrease depending on the concentration of GSH, the signal of TempoMC was generally constant. In addition, TempoMC showed only a slight decrease in signal even after 7 days, proving that it exists in a stable state. After mixing the AsA solution, the ESR signal was gradually decreased by the redox reaction. The EPR signals of TempoMC capillaries were decreased by irradiation. The phantom including TempoMC radical were clearly visualized by DNP-MRI. As described above, TempoMC/GSH solution behaved similar reactivity to Tempol/GSH solution, proving to be more stable and more useful as a redox probe. We evaluated TempoMC/GSH solution as a new useful redox probe. TempoMC /GSH solution is much more stable than the conventional Tempol/GSH solution, and is expected to be applied in the future, including in vivo. [ABSTRACT FROM AUTHOR]

Radiation treatment effectiveness is assessed through the observation of morphological changes with CT or MRI images after treatment. The treatment efficacy of radiotherapy depends on redox modulation in tumor tissue, such as hydroxyl radicals and of reactive oxygen species generated by irradiation. Therefore, redox status may be a prognostic factor response to radiotherapy. However, spatiotemporal response of the redox metabolism in tumor tissue post-irradiation remains unknown. The purpose of this study was to detect early changes in the redox status in tumor tissue after irradiation using in vivo dynamic nuclear polarization (DNP)-MRI, to clarify the key molecules that cause these changes, and to compare these changes with early changes in lactate metabolism using hyperpolarized 13C magnetic resonance spectroscopy (MRS). To monitor the response of tumor redox status after irradiation, redox imaging using in vivo DNP MRI/ Carbamoyl PROXYL (CmP) as redox sensitive DNP probe was performed after 5 Gy irradiation. To clarify the relationship between redox status alteration and treatment efficacy, in vivo DNP MRI was performed before and after irradiation by 2 and 5 Gy. In addition, tissue GSH and AsA levels on day 1 post irradiation were determined by HPLC. To observe the Warburg effect after radiation treatment, dissolution DNP study using hyperpolarized ¹³C pyruvate was performed before and after irradiation. The DNP image intensity in the tumor demonstrated a maximum value approximately four minutes after CmP administration, thereafter the image intensity was decreased by the redox reaction. The tumor GSH and AsA level on day 1 post irradiation were decreased compared to the control group. Production of hyperpolarized ¹³C lactate in tumor tissue did not change before and after irradiation. Our study highlights that redox status in tumor tissue is already significantly decreased on day 1 before the detection of any morphological changes, even after irradiation with a dose as low as 2 Gy. Early changes in this redox status may be related decreases in glutathione and ascorbic acid levels in the tumor tissue after irradiation, which may alter earlier than 13C pyruvate hyperpolarized MRS, based on lactate metabolism. Therefore, early assessment of change in decay rate using in vivo DNP-MRI/CmP probing may predict the subsequent radiotherapy effect. [ABSTRACT FROM AUTHOR]

Cardiac arrhythmias are usually treated with invasive, time consuming catheter ablation techniques. While recently stereotactic body radiotherapy (SBRT) is an emerging non-invasive treatment in the management of cardiac arrhythmias. Although we used the motion management by compression techniques for the reduction of the internal target volume, we did not use the gating and real-time tracking techniques. We assessed the necessity of the precise target planning and monitoring the complex respiratory and cardiac motion to cardiac radioablation to the cavotricuspid isthmus (CTI) by pathological assessment in mini pigs. All animal procedures were approved by institutional animal care and use committee and performed in full compliance with its guidelines. Four mini pigs underwent magnetic resonance (MR) and electrophysiology assessment using electroanatomic mapping (EAM) before and 3 months after SBRT with single-fraction doses of 25Gy. The target of CTI was defined by cardiologist. We defined the internal margin (IM), respiratory: SI 7 mm, AP 3 mm, LR 3 mm, cardiac motion: 3 mm in all direction and set up margin (SM): 5 mm in all direction. Then, planning target volume (PTV) margin: IM + SM = SI 15 mm, AP 10mm, LR 10 mm were added to the target, defining PTV.MR examination, including diffusion-weighted, dynamic Gd-enhanced, spectroscopy, and T2-weighted images were performed before and 3 months after SBRT, followed by histopathologic examination. Radiation oncologist and radiologist evaluated the detectability and image quality for the irradiated site. MRI findings of the CTI radioablation lesion was compared to electrophysiology and histopathology findings. A total dose of 25 Gy was successfully delivered to PTV in a single procedure in all mini pigs. EAM visualized the irradiated site and confirmed clockwise conduction block across the CTI. MRI could not detect the radiation injury clearly. Pathological examinations were analyzed after 3 months of follow-up, fibrous hyperplasia and capillary hyperplasia were observed around the nerve bundle beyond CTI in all pigs. The atrophy and necrosis of the nerve bundle itself is scarce. These data demonstrated the feasibility of SBRT for creating conduction block across the CTI in mini pigs. Fibrosis or scarring around the nerve bundle beyond CTI may affect the radiation injury. Then, precise margins of cardiac radioablation to the cavotricuspid isthmus will reduce the radiation injury. Not only gating and breath-hold, but also including the use of real-time tracking such as MRI-guidance cardiac radiosurgery will open the possibility of treating cardiac arrhythmias patients completely safety and noninvasively. [ABSTRACT FROM AUTHOR]