Objective：The aim of this study was to examine the relationships between the timing of gait acquisition and the length of hospitalization, and to clarify the differences in background factors and functional recovery during the early postoperative period and their effect on the variability in gait acquisition.
Methods：We recruited 148 patients who underwent total knee arthroplasty (TKA) at three hospitals. The participants were divided into two groups on the basis of the number of days needed to achieve independent gait at ≤14 days after surgery (group A) and ＞14 days after surgery (group B). We compared the background factors between the two groups. Additionally, we compared the preoperative and postoperative function in each group.
Results：We observed a significant positive correlation between the number of days needed to achieve independent gait and the length of hospitalization. In group A, the significant background factors were younger age and higher preoperative activity level. In group A, compared with the level of preoperative function, the postoperative maximum knee extension angle on the operated side and pain had significantly improved. In both groups, the postoperative knee extensor strength on the operated side, knee extensor strength on the nonoperated side, knee flexion strength on the operated side, maximum knee flexion angle on the operated side, and walking speed were significantly reduced.
Conclusion：During early rehabilitation, it is necessary to consider the age and previous activities of patients. In addition, we suggest that early rehabilitation with a focus on reducing pain by alleviating inflammation and improving maximum knee extension angle on the operated side may be effective for fast acquisition of gait.

Objective：To elucidate factors associated with physical function and clarify the actual condition of functional deterioration in patients with knee osteoarthritis (OA) prior to total knee arthroplasty (TKA)．

Methods：We enrolled 467 patients with severe knee OA and preoperatively assessed the following parameters：background factors (sex, age, BMI, K-L grade, and pain) and physical function (muscle strength of knee extensors and flexors, and knee joint angles). A multiple regression analysis was performed to determine the relationship between the independent background factors and dependent physical functions. The median of preoperative function based on selected factors of physical function was calculated.

Results：Based on the multiple regression analysis, sex, BMI, K-L grade, and pain statistically significantly correlated with muscle strength of knee extensors and flexors. Sex and BMI statistically significantly correlated with knee joint flexion angle. K-L grade statistically significantly correlated with knee joint extension angle. The median of muscle strength for knee extension was 0.98/0.92 Nm/kg (Grade 3/Grade 4) for males and 0.70/0.59 Nm/kg for females. The median of muscle strength for knee flexion was 0.53/0.45 Nm/kg for males, 0.36/0.30 Nm/kg for females. The median for knee joint flexion angle was 130° for males and 120° for females. The median for knee joint extension angle was -5°/-10° (Grade 3/Grade 4)．

Conclusion：We clarified the degree of muscle strength and range of motion before TKA in patients with knee OA. We believe that the findings obtained in this study will contribute to explaining the functional deterioration of patients with knee OA.

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.

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.

While the COVID-19 epidemic required the ability to confront infection prevention practices, its education for medical students remained inadequate. Herein, we have developed an infection practice simulation course for medical students, based on the simulation education method. The course is a compulsory part of the medical school curriculum. Features of the course include adoption of small group education by tutorial method, medical interviews of simulated patients, scenario simulation, supervised discussions and presentations between medical students, efficient point learning using worksheets, achievement assessment using OSCE, course direction by an infectious disease specialist, and university-wide educational participation from all clinical department doctors. The course was designed so that students could be guided to think carefully and be aware of their interactions. In addition, it was expected that participation in the course would have a lifelong educational effect on the medical doctors.