24 research outputs found
Impact of HBV Infection on Outcomes of Direct-Acting Antiviral Therapy of Chronic Hepatitis C
Background: Most clinical trials of direct-acting antiviral (DAA) therapy for hepatitis C virus (HCV) infection have excluded hepatitis B virus (HBV) coinfection, and little is known about the effects of DAA on chronic hepatitis C patients with HBV coinfection. Recent studies have reported that DAA therapy for HCV can also cause HBV reactivation in patients with HBV and HCV coinfection. The aim of this study was to assess the effects of DAA on sustained virologic response (SVR) and HBV reactivation in patients with chronic hepatitis C. Methods: Participants comprised 199 chronic hepatitis C patients who received DAA therapy (96 men, 103 women; mean age, 66.7 ± 12.0 years). Results: Twelve patients were coinfected with HCV and HBV. Sixty patients were HBV surface antigen negative but positive for hepatitis B core antibody and/or hepatitis B surface antibody, and one hundred and twenty-seven patients had not been exposed to HBV. Rates of SVR in HBV and HCV coinfected patients, HBV prior infection, and no exposure to HBV were 100, 95, and 97%, respectively. Significant differences were seen between each group. No case showed HBV reactivation. Conclusions: DAA treatments were effective in patients with HBV coinfection or HBV prior infection, as well as HCV monoinfection. As the number of cases was small, we still suggest caution regarding HBV reactivation in HCV and HBV coinfected patients undergoing treatment with DAA
Effect of neutron irradiation on the microstructure of modified SUS316 stainless steels
The microstructures, prior and posterior to volumetrically remarkable swelling, of heavily neutron-irradiated specimens of compositionally-modified SUS316 based steel were carefully studied and characterized by using transmission electron microscope(TEM) and high resolution TEM to make clear an onset mechanism of radiation-induced swelling as well as an effect of neutron irradiation on microstructure. As the results of TEM study, it was demonstrated that the microstructural evolutions, including radiation-induced swelling, depended strongly on the irradiation condition. The relationship between the onset of swelling and microstructural evolution is quite complicated but the effects of irradiation temperature on microstructural changes appear to be relatively large. The onset mechanisms of swelling at a specific temperature or temperature range are discussed from the viewpoint of microstructure in this paper
Conceptual Study on Recriticality Prevention Core Having Duplex Pellets with Neutron Absorber in Outer Core in a Fast Reactor
In a fast reactor, we evaluated a new core concept that prevents severe recriticality after whole-scale molten formation in a severe accident. A core concept in which Duplex pellets including neutron absorber are loaded in the outer core has been proposed. Analysis by the continuous energy model Monte Carlo code MVP using the JENDL-4.0 nuclear data library revealed that this fast reactor core has large negative reactivity due to fuel melting at the time of a severe accident, so that the core prevents recriticality. Regarding the core nuclear and thermal characteristics, the loading of Duplex pellets including neutron absorber in the outer core caused no significant differences from the normal core without Duplex pellets
Development of Anthropomorphic Multi-D.O.F. Master-Slave Arm for Mutual Telexistence
We developed a robotic arm for a master-slave system to support "mutual telexistence," which realizes remote dexterous manipulation tasks and close physical communication with other people using gestures. In this paper, we describe the specifications of the experimental setup of the master-slave arm to demonstrate the feasibility of the mutual telexistence concept. We developed the master arm of a telexistence robot for interpersonal communication. The last degree of the 7-degree-of-freedom slave arm is resolved by placing a small orientation sensor on the operator's arm. This master arm is made light and impedance control is applied in order to grant the operator as much freedom of movement as possible. For this development stage, we compared three control methods and confirmed that the impedance control method is the most appropriate to this system
Large or multiple pseudocysts can impede or complicate the nonsurgical treatment of pancreatolithiasis
Objectives: We aimed to determine when a coexisting pseudocyst was likely to complicate the nonsurgical treatment of pancreatolithiasis.
Methods: We treated 165 patients with pancreatolithiasis nonsurgically between 1992 and 2020, including 21 with pseudocysts. Twelve patients had a single pseudocyst less than 60 mm in diameter. Pseudocysts in the other nine patients had diameters of at least 60 mm or were multiple. The locations of pseudocysts along the length of the pancreas varied from the area with stone involvement to the pancreatic tail. We compared the outcomes in these groups.
Results: We found no significant differences in pain relief, stone clearance, stone recurrence, or the likelihood of adverse events between pseudocyst groups or between patients with vs without pseudocysts. However, 4 of 9 patients with large or multiple pseudocysts required transition to surgical treatment (44%) compared with 13 of 144 patients with pancreatolithiasis and no pseudocyst (9.0%) (P=0.006).
Conclusions: Patients with smaller pseudocysts typically underwent nonsurgical stone clearance successfully with few adverse events, similar to findings in patients with pancreatolithiasis and no pseudocysts. Pancreatolithiasis complicated by large or multiple pseudocysts did not cause more adverse events but was more likely to require transition to surgery compared with pancreatolithiasis without pseudocysts. In patients with large or multiple pseudocysts, early transition to surgery should be considered when nonsurgical treatment is ineffective