Development of an Evaluation System for Magnetic Resonance Imaging Based Three-Dimensional Modeling of a Transfemoral Prosthetic Socket Using Finite Elements

Recent technologies have suggested the utilization of three-dimensional (3D) printingtechnology to enhance the fabrication accuracy of prosthetics. Accordingly, simulations are used toobtain precise parameters for subject-specified prosthetic socket. This study proposes an evaluationsystem to measure the accuracy of a subject-specific 3D transfemoral residuum model duringthe interaction with the socket in conjunction with the application of finite element methods.The proposed system can be used in future validations of socket fabrication. The evaluation isbased on the measurement of the residuum’s soft tissue deformation inside two types of prostheticsockets. In comparison with other studies, the 3D models were constructed with magnetic resonanceimages (MRI) with the aid of computer-aided design (CAD) software. The measurement of soft tissuedeformation was conducted based on the measurement of the volumetric value of fat, muscle andskin in the pre- and post-donning phases. The result yielded a promising correlation coefficient valuebetween the simulation and the experiment in the soft tissue deformation evaluation. The relationof the muscle–fat ratio in the residuum is extremely important in the determination of the abilityof the prosthetic to deform. The environment during the socket fitting session was similar to thatdefined by the set boundary conditions in simulations. In view of the promising results of thisstudy, the evaluation system proposed herein is considered reliable and is envisaged to be used infuture research

Impact of the day of the week on the discontinuation of broad-spectrum antibiotic prescriptions; a multi-centered observational study

To encourage and guide antimicrobial stewardship team (AST) activity and promote appropriate antibiotic use, we studied the impact of day of the week on the initiation and discontinuation of antibiotic administration. This was a multicenter observational study conducted at 8 Japanese hospitals from April 1 to September 30, 2019, targeting patients who underwent treatment with broad-spectrum antibiotics, such as anti-methicillin-resistant Staphylococcus aureus agents and anti-pseudomonal agents. We compared the weekly numbers of initiations and discontinuations of antibiotic prescription on each day of the week or on the days after a holiday. There was no statistical difference in the number of antibiotic initiations on both weekdays and the day after a holiday. However, antibiotic discontinuation was significantly higher from Tuesday onward than Monday and from the second day than the first day after a holiday. Similar trends were observed regardless of the categories of antibiotics, hospital and admission ward, and AST activity. This study suggests that broad-spectrum antibiotics tend to be continued during weekends and holidays and are most likely to be discontinued on Tuesday or the second day after a holiday. This was probably due to behavioral factors beyond medical indications, requiring further antimicrobial stewardship efforts in the future

EWSR1-ATF1融合遺伝子を持つ歯原性明細胞癌細胞株の樹立と性状解析

Objective: Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic tumor (MOT) characterized by sheets and lobules of vacuolated and clear cells. To understand the biology of CCOC, we established a new cell line, CCOC-T, with EWSR1-ATF1 fusion gene from a mandible tumor with distant metastasis and characterized this cell line. Materials and methods: To detect the EWSR1-ATF1 fusion gene, we used three CCOC cases, including the present case, by RT-PCR and FISH analysis. We characterized established CCOC-T cells by checking cell growth, invasion and the expression of odontogenic factors and bone-related factors. Moreover, the gene expression profile of CCOC-T cells was examined by microarray analysis. Results: Histologically, the primary tumor was comprised of cords and nests containing clear and squamoid cells separated by fibrous septa. In addition, ameloblastomatous islands with palisaded peripheral cells were observed, indicating probable odontogenic origin. This tumor expressed the fusion gene EWSR1-ATF1, which underlies the etiology of hyalinizing clear cell carcinoma (HCCC) and potentially that of CCOC. We found a breakpoint in the EWSR1-ATF1 fusion to be the same as that reported in HCCC. Established CCOC-T cells grew extremely slowly, but the cells showed highly invasive activity. Moreover, CCOC-T cells expressed bone-related molecules, odontogenic factors, and epithelial mesenchymal transition (EMT)-related molecules. Conclusion: To the best of our knowledge, this is the first report on the establishment of a CCOC cell line. CCOC-T cells serve as a useful in vitro model for understanding the pathogenesis and nature of MOT

A Method to Analyze Dynamics Properties of Transfemoral Prosthesis

Abstract.The methodto compute gait cycle forces and moments acting on the hip and knee joints of a lower limb with a trans-femoral prosthesis were investigated. A 3D model of the lower limb with prosthesis was created using CAD software and based on MRI data and real size dimension. The transfemoral prosthesis was modelled as a coupled of links with two revolution joints at hip and knee joint. This coupled link was connected to a bar with translation joint to description the distance walked of people in gait cycle. All parts of the prosthesis were measured and a full-size 3D model was created.The kinematics parameters of a lower limb with a prosthesis were determined from motion-captured system data. The reaction force was measured with a force sensor in the footplate. The 3D model of the prosthesis was exported to MatlabSimmechanics. The input data which are kinematic parameters were applied to calculate the forces and moments acting on the joints. The results of this study present a method to analyse the dynamic properties of transfemoral prosthesis including speed of the gait. It could be used to calculate the load transferred from the socket to the residual limb. They could also be used to design the structure of a prosthesis and optimize the dynamic characteristics of such a prosthesis