Removal of intrahepatic bile duct stone could reduce the risk of cholangiocarcinoma: A single-center retrospective study in South Korea

BACKGROUND Intrahepatic duct(IHD)stones are among the most important risk factors for cholangiocarcinoma(CCC).Approximately 10%of patients with IHD stones develop CCC;however,there are limited studies regarding the effect of IHD stone removal on CCC development.AIM To investigate the association between IHD stone removal and CCC development.METHODS We retrospectively analyzed 397 patients with IHD stones at a tertiary referral center between January 2011 and December 2020.RESULTS CCC occurred in 36 of the 397 enrolled patients.In univariate analysis,chronic hepatitis B infection(11.1%vs 3.0%,P=0.03),carbohydrate antigen 19-9(CA19-9,176.00 vs 11.96 II/mL,P=0.010),stone located in left or both lobes(86.1%vs 70.1%,P=0.042),focal atrophy(52.8%vs 26.9%,P=0.001),duct stricture(47.2%vs 24.9%,P=0.004),and removal status of IHD stone(33.3%vs 63.2%,P<0.001)were significantly different between IHD stone patients with and without CCC.In the multivariate analysis,CA19-9>upper normal limit,carcinoembryonic antigen>upper normal limit,stones located in the left or both lobes,focal atrophy,and complete removal of IHD stones without recurrence were independent factors influencing CCC development.However,the type of removal method was not associated with CCC risk.CONCLUSION Complete removal of IHD stones without recurrence could reduce CCC risk.

Metastatic pancreatic solitary fibrous tumor: A case report

BACKGROUND Solitary fibrous tumor(SFT)is a rare mesenchymal tumor that is most commonly found in the pleura but can also originate from non-pleural sites.Among the nonpleural localizations,the pancreas is extremely rare.In particular,metastasis to the pancreas from the central nervous system(CNS)is extremely rare,with only two cases reported so far.We report a case of recurrence in the pancreas 14 years after the initial complete surgical removal of a tumor in the CNS.CASE SUMMARY A 68-year-old man with a past medical history of recurrent meningeal hemangiopericytoma,currently referred to as SFT,presented to the hospital with jaundice.The patient was first diagnosed with an 8cm-sized meningeal hemangiopericytoma fourteen years ago and underwent osteoplastic craniotomy.After 16 mo,imaging showed recurrence and he underwent gamma knife radiosurgery(GKRS).2 years later,imaging showed recurrence again leading to a second GKRS.5 years later,recurrence was again suspected leading to a second craniotomy.Since then 3 years had passed,and imaging showed a 3.5cm-sized mass lesion on the pancreatic head with obstruction of the pancreatic and bile ducts.Endosonography with fine-needle aspiration biopsy was done preoperatively and aided in the diagnosis of SFT.The patient underwent pyloruspreserving pancreaticoduodenectomy.Pathologic findings of the resected pancreatic specimen,consistent with the previously resected brain specimen,confirmed the diagnosis of SFT.CONCLUSION The rarity and lack of knowledge about SFTs make suspecting and diagnosing this disease challenging.We believe that a report of metastatic pancreatic SFT from the CNS will contribute to a better understanding of this rare disease.

Neural Network-Based State of Charge Estimation Method for Lithium-ion Batteries Based on Temperature

Lithium-ion batteries are commonly used in electric vehicles,mobile phones,and laptops.These batteries demonstrate several advantages,such as environmental friendliness,high energy density,and long life.However,battery overcharging and overdischarging may occur if the batteries are not monitored continuously.Overcharging causesfire and explosion casualties,and overdischar-ging causes a reduction in the battery capacity and life.In addition,the internal resistance of such batteries varies depending on their external temperature,elec-trolyte,cathode material,and other factors;the capacity of the batteries decreases with temperature.In this study,we develop a method for estimating the state of charge(SOC)using a neural network model that is best suited to the external tem-perature of such batteries based on their characteristics.During our simulation,we acquired data at temperatures of 25°C,30°C,35°C,and 40°C.Based on the tem-perature parameters,the voltage,current,and time parameters were obtained,and six cycles of the parameters based on the temperature were used for the experi-ment.Experimental data to verify the proposed method were obtained through a discharge experiment conducted using a vehicle driving simulator.The experi-mental data were provided as inputs to three types of neural network models:mul-tilayer neural network(MNN),long short-term memory(LSTM),and gated recurrent unit(GRU).The neural network models were trained and optimized for the specific temperatures measured during the experiment,and the SOC was estimated by selecting the most suitable model for each temperature.The experimental results revealed that the mean absolute errors of the MNN,LSTM,and GRU using the proposed method were 2.17%,2.19%,and 2.15%,respec-tively,which are better than those of the conventional method(4.47%,4.60%,and 4.40%).Finally,SOC estimation based on GRU using the proposed method was found to be 2.15%,which was the most accurate.

Hwabyung Experiences Among Korean Immigrant Women in the United States

Hwabyung is an indigenous psychiatric illness commonly found among Korean women. Using hwabyung, this article describes the psychological ramifications of immigration experiences among Korean immigrant women in the United States. Data collected from an anonymous survey of adult Korean immigrant women （n = 143） were used for a statistical analysis. The findings highlight the significant effects of self-esteem, social support, financial hardship, and family cohesion on the changes in the hwabyung symptoms among Korean immigrant women. Based on the findings, the implications for practice and future study are discussed. Also discussed are the global significance of migrant women and their mental health issues.