Background Postoperative cholangitis is a common complication of pancreaticoduodenectomy. Frequent cholangitis impairs patients' quality of life after pancreaticoduodenectomy. However, the risk factors for recurrence of cholangitis remain unclear. Hence, this retrospective study aimed to identify risk factors for recurrence of cholangitis after pancreaticoduodenectomy. Methods The medical records of patients who underwent pancreaticoduodenectomy between 2015 and 2019 in our institution were retrospectively reviewed. At least two episodes of cholangitis a year after pancreaticoduodenectomy were defined as 'recurrence of cholangitis' in the present study. Univariate and multivariate analyses were performed. ResultsThe recurrence of cholangitis occurred in 40 of 207 patients (19.3%). Multivariate analysis revealed that internal stent (external, RR: 2.16, P = 0.026; none, RR: 4.76, P = 0.011), firm pancreas (RR: 2.61, P = 0.021), constipation (RR: 3.49, P = 0.008), and postoperative total bilirubin[1.7 mg/dL (RR: 2.94, P = 0.006) were risk factors of recurrence of cholangitis. Among patients with internal stents (n = 54), those with remnant stents beyond 5 months had more frequent recurrence of cholangitis (C5 months, 75%; \5 months, 30%). Conclusions Internal stents, firm pancreas, constipation, and postoperative high bilirubin levels are risk factors for cholangitis recurrence after pancreaticoduodenectomy. In addition, the long-term implantation of internal stents may trigger cholangitis recurrence.

In recent years, the volumes of data collected by Earth observation missions have significantly increased. With the need to speed up transmission of those high-rate mission data from space to ground, JAXA plans to replace X-band with Ka-band for the direct space-toground downlink, for future missions after the Advanced Optical Satellite, to support the high data rate communications. To accommodate the requirement, JAXA has been developing new Ka-band reception capability to enable direct reception of Ka-band radio signals from spacecrafts in the near-Earth regime.

The purpose of this study was to determine the physiological and biochemical properties of hindlimb muscles after hypoventilation (HPO) induced by bilateral phrenic nerve denervation. Male Wistar rats (10 weeks-old) underwent HPO by the phrenic nerve denervation at the cervical level or sham surgery. Analyses were performed 4, 8, and 12 weeks after the surgery. The myosin heavy chain (MHC) isoform profile and in vitro isometric contractile properties of the soleus (SOL) and extensor digitrum longus muscles (EDL) were analyzed. From the postoperative period, HPO induced characteristic changes in SpO 2 such as hypoventilation disorder. After 12 weeks, significant increases in MHC1 and significant decreases in MHC2a were observed in the MHC isoform composition in SOL. Moreover, significant increases in MHC2a and significant decreases in MHC2b were also observed in the MHC isoform composition in EDL muscles in the HPO compared with sham (SHM) group. In our study, the tidal volume after unilateral phrenic nerve denervation decreased by approximately 12%, and that after bilateral phrenic nerve denervation decreased by approximately 35%. We concluded that the reduction in behavioral activity levels in the HPO group may have resulted in changes of the peripheral skeletal muscles as a result of disuse atrophy.