Using a mouse model, we previously demonstrated that subcutaneous infection with the JaTH160 strain of Japanese encephalitis virus (JEV) causes significantly higher virulence and stronger virus propagation in the brain compared with that of the JaOArS982 strain. We also showed that the JaTH160 strain, but not JaOArS982, expresses the NS1’ protein and that NS1’ enhances JEV production in avian cells and embryonated chicken eggs. In this study, we examined whether NS1’ expression affects virulence in mice infected with the JaOArS982 and JaTH160 strains using the corresponding recombinant viruses S982-IC and JaTH-IC. Expression of the NS1’ protein in S982-IC diminished the mortality in mice, whereas S982-IC viruses without NS1’ caused 40–60% mortality. However, the viral loads in the brains of these mice were not significantly different despite the dvariation in NS1’ expression. JaTH-IC viruses depleted of the NS1’ protein exhibited high mortality levels, similar to those of the virus expressing NS1’. Previous studies showed that the NS1’ protein plays a role in the enhanced virulence of the JEV SA14 strain in mice. However, our current data suggest that NS1’ protein expression in S982-IC reduces, rather than enhances, the mortality in mice. Thus, the effect of NS1’ on pathogenicity in vivo may vary among virus strains. Our data also suggest that the reduced mortality resulting from NS1’ expression in S982-IC is not simply due to viral replication in the brains. Further investigation is needed to uncover the mechanism by which NS1’ affects pathogenicity in JEV-infected animals.

Using a mouse model,we previously demonstrated that subcutaneous infection with the JaTH160 strainof Japaneseencephalitis virus (JEV) causes significantly higher virulence and strongervirus propagation in the brain compared with that of the JaOArS982strain. We also showed that the JaTH160 strain,but not JaOArS982, expresses the NS1’ protein and that NS1’ enhances JEVproduction in avian cells and embryonated chicken eggs. In this study, weexamined whether NS1’ expression affects virulence in mice infected with theJaOArS982 and JaTH160 strains using the corresponding recombinant viruses S982-ICand JaTH-IC.Expression of the NS1’ protein in S982-IC diminishedthe mortality in mice, whereas S982-IC viruses without NS1’ caused 40% mortality.However, the viral loads in the brains of these mice were not significantlydifferent despite the difference in NS1’ expression. JaTH-IC viruses depletedof the NS1’ protein exhibited high mortality levels, similar to those of thevirus expressing NS1’.Previousstudies showed that the NS1’ protein plays a role in the enhanced virulenceof the JEV SA14 strain in mice. However, ourcurrent data suggest that NS1’ protein expression in S982-IC reduces,rather than enhances, the mortality in mice. Thus, the effect of NS1’ on pathogenicity invivo may vary among virus strains. Our data also suggest that the reducedmortality resulting from NS1’ expression in S982-IC is not simply due to viralreplication in the brains. Furtherinvestigation is needed to uncover the mechanism by which NS1’ affectspathogenicity in JEV-infected animals.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease endemic in East Asia. Transmitted to other organisms by infected ticks, the SFTS virus (SFTSV) and is endemic to Nagasaki in western Japan. However, epidemiological information regarding SFTSV in Nagasaki ticks has not been available to date. In this study, we began by examining the sensitivities of SFTSV gene detection by real-time RT-PCR and virus isolation in cultured cells and mice. These methods could detect SFTSV in the samples containing more than 4 × 10⁰ ffu. Next, we attempted to isolate SFTSV and to detect viral gene in 2,222 nymph and adult ticks collected from May to August 2013 among seven regions of Nagasaki. However, neither virus isolation nor viral gene detection were confirmed in the tick pools. SFTSV positivity rates are considered to be very low in ticks, and viral loads are also very limited. Further investigations increasing the number of ticks and including larval samples as well as improved detection methods, may be required to find SFTSV-positive ticks in this region.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease that is endemic in East Asia. The SFTS virus (SFTSV) is transmitted to other organisms by infected ticks and is endemic to Nagasaki in western Japan. However, epidemiological information regarding SFTSV in Nagasaki ticks has not been elucidated. In this study, we first examined the sensitivities of SFTSV gene detection by real-time RT-PCR and virus isolation in cultured cells and mice. These methods could detect SFTSV in the samples containing more than 4 × 10⁰ ffu. Next, we attempted to isolate SFTSV and to detect viral gene in 2,222 nymph and adult ticks collected from May to August 2013 among seven regions of Nagasaki. However, neither virus isolation nor viral gene detection were confirmed in those tick pools. SFTSV positivity rates are considered very low in ticks and viral loads in ticks are also very limited. Further investigation by increasing the number of ticks and including larval samples in the investigation, as well as improved detection methods, may be required to find SFTSV-positive ticks in this region.

Background/Aims: Endoscopic transpapillary gallbladder drainage (ETGBD) is useful for the treatment of acute cholecystitis; however, the technique is difficult to perform. When intraductal ultrasonography (IDUS) is combined with ETGBD, the orifice of the cystic duct in the common bile duct may be more easily detected in the cannulation procedure. The aim of this study was to evaluate the efficacy of ETGBD with IDUS compared with that of ETGBD alone. Methods: A total of 100 consecutive patients with acute cholecystitis requiring ETGBD were retrospectively recruited. The first 50 consecutive patients were treated using ETGBD without IDUS, and the next 50 patients were treated using ETGBD with IDUS. Through propensity score matching analysis, we compared the clinical outcomes between the groups. The primary outcome was the technical success rate. Results: The technical success rate of ETGBD with IDUS was significantly higher than that of ETGBD without IDUS (92.0% vs. 76.0%, p=0.044). There was no significant difference in procedure length between the two groups (74.0 min vs. 66.7 min, p=0.310). The complication rate of ETGBD with IDUS was significantly higher than that of ETGBD without IDUS (6.0% vs. 0%, p<0.001); however, only one case showed an IDUS technique-related complication (pancreatitis). Conclusions The assistance of IDUS may be useful in ETGBD.

Background/Aims: Asymptomatic esophageal eosinophilia (aEE) is considered to be a potential precursor of eosinophilic esophagitis (EoE). However, there are few clinical parameters that can be used to evaluate the disease. Therefore, we aimed to clarify the factors involved in the symptoms of EoE by examining the clinicopathological differences between aEE and EoE. Methods: We reviewed 41 patients with esophageal eosinophilia who underwent endoscopic ultrasonography and high-resolution manometry. They were divided into the aEE group (n=16) and the EoE group (n=25) using the Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease score. The patients’ clinicopathological findings were collected and examined. Results: The median Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease score was 3.0 in the aEE group and 10.0 in the EoE group. There was no significant difference in patient characteristics, endoscopic findings and pathological findings. The cutoff value for wall thickening was 3.13 mm for the total esophageal wall thickness and 2.30 mm for the thickness from the surface to the muscular layer (total esophageal wall thickness: 84.0% sensitivity, 75.0% specificity; thickness from the surface to the muscular layer: 84.0% sensitivity, 68.7% specificity).The high-resolution manometry study was abnormal in seven patients (43.8%) in the aEE group and in 12 (48.0%) in the EoE group. The contractile front velocity was slower in the EoE group (p=0.026). Conclusions The esophageal wall thickening in the lower portion of the esophagus is an important clinical factors related to the symptoms in patients with EoE.