Initial experience of a deep learning application for the differentiation of Kikuchi-Fujimoto's disease from tuberculous lymphadenitis on neck CECT.

Neck contrast-enhanced CT (CECT) is a routine tool used to evaluate patients with cervical lymphadenopathy. This study aimed to evaluate the ability of convolutional neural networks (CNNs) to classify Kikuchi-Fujimoto's disease (KD) and cervical tuberculous lymphadenitis (CTL) on neck CECT in patients with benign cervical lymphadenopathy. A retrospective analysis of consecutive patients with biopsy-confirmed KD and CTL in a single center, from January 2012 to June 2020 was performed. This study included 198 patients of whom 125 patients (mean age, 25.1 years ± 8.7, 31 men) had KD and 73 patients (mean age, 41.0 years ± 16.8, 34 men) had CTL. A neuroradiologist manually labelled the enlarged lymph nodes on the CECT images. Using these labels as the reference standard, a CNNs was developed to classify the findings as KD or CTL. The CT images were divided into training (70%), validation (10%), and test (20%) subsets. As a supervised augmentation method, the Cut&Remain method was applied to improve performance. The best area under the receiver operating characteristic curve for classifying KD from CTL for the test set was 0.91. This study shows that the differentiation of KD from CTL on neck CECT using a CNNs is feasible with high diagnostic performance.

Long QT Syndrome KCNH2 Variant Induces hERG1a/1b Subunit Imbalance in Patient-Specific Induced Pluripotent Stem Cell-Derived Cardiomyocytes.

[Figure: see text].

Current and New Approaches to Predict the Deflections of One-Way Flexural Members with a Focus on Composite Steel Deck Slabs Voided by Circular Tubes.

A new type of composite voided slab, the TUBEDECK (TD), which utilizes the structural function of profiled steel decks, has recently been proposed. Previous studies have confirmed that the flexural strength of TD slabs can be calculated based on the full composite contribution of the steel deck, but for long-span flexural members, the deflection serviceability requirement is often dominant. Herein, we derived a novel deflection prediction approach using the results of flexural tests on slab specimens, focusing on TD slabs. First, deflection prediction based on modifications of the current code was proposed. Results revealed that TD slabs exhibited smaller long-term deflections and at least 10% longer maximum span lengths than solid slabs, indicating their greater efficiency. Second, a novel rational method was derived for predicting deflections without computing the effective moment of inertia. The ultimate deflections predicted by the proposed method correlated closely with the deflection under maximum bending moments. To calculate immediate deflections, variation functions for the concrete strain at the extreme compression fiber and neutral axis depth were assumed with predictions in good agreement with experiments. The proposed procedure has important implications in highlighting a new perspective on the deflection prediction of reinforced concrete and composite flexural members.

Cyclic Loading Performance of Radius-Cut Double Coke-Shaped Strip Dampers.

Conventional slit dampers are widely used for the purpose of seismic retrofitting, however, the structure of these dampers is susceptible to fractures, due to stress concentration at the ends of the strips in the event of large earthquakes. To address this issue, a novel radius-cut coke-shaped strip damper featuring improved ductility is proposed herein. This damper was developed based on the moment distribution over the strip when both its ends were constrained. The height-to-width ratio of the strip was increased to induce bending rather than shear deformation, and the reduced beam section method was employed. A radius-cut section was used to intentionally focus the stress to induce the plastic hinge. This reduced the fracture fragility of the specimen, resulting in an increased inelastic deformation capacity. Cyclic loading tests were conducted to verify damping performance against earthquakes. Experiments and finite element analyses proved that the coke-shaped damper exhibits improved ductility. The final fracture occurred in the radius-cut section after sufficient energy dissipation during cyclic loading. The results also indicated further improvements in strength due to the membrane effect under cyclic loading, caused by the tensile resistance of the strip due to its constrained ends.

Three-dimensional analysis of acetabular orientation using a semi-automated algorithm.

Understanding the morphology of the acetabulum is necessary for preoperative evaluation in hip surgery. The purpose of this study was to (1) establish a novel method for measuring three-dimensional (3D) acetabular orientation, (2) quantify the reliability of this method, and (3) describe relevant characteristics of three-dimensional (3D) acetabular orientation among normal Asian subjects. Computed tomography (CT) scans of the pelvis that had been performed for suspected non-musculoskeletal conditions were obtained from 200 subjects (60 males, 140 females). A novel method was developed to measure 3D acetabular orientation with a semi-automatically determined pelvic coordinate system based on the anterior pelvic plane (APP). To quantify the robustness of our method, we analyzed the results obtained from 20 patients at different times and with different raters and pelvic poses in the same CT volume. To determine morphological differences of the acetabulum by age and sex, we analyzed the parameters of 200 CT volumes. Each intraclass correlation coefficient (ICC) values for intra- and inter-observer reliability were over 0.975 and 0.945, demonstrating high reliability. Furthermore, agreement between the angles determined from the original volume and the rotated volume was nearly perfect (ICCs > 0.956). Multiple linear regression analysis with age and sex as covariates indicated that acetabular inclination was not significantly associated with age (p = 0.687) or sex (p = 0.09). There was also no evidence that acetabular anteversion was associated with age (p = 0.383) or sex (p = 0.53). Our method showed excellent reliability for determining acetabular orientation, as it is robust, fast, and easily applicable to larger populations. In addition, the results of the analysis of acetabular orientation by age and sex can be used as a reference in various diagnostic procedures in orthopedics.

A robust method to extract the anterior pelvic plane from CT volume independent of pelvic pose.

PURPOSE: The anterior pelvic plane (APP) is commonly used as a reference plane to assess acetabular orientation. However, conventional methods for determining the APP may not be accurate and are prone to user variability. To overcome these issues, we developed a robust method to accurately extract the APP independent of pelvic pose using three-dimensional pelvic computed tomography (CT). MATERIALS AND METHODS: Twenty-eight studies for suspected nonmusculoskeletal conditions were obtained. The APP was determined by four landmarks that were automatically extracted from user-defined regions of interest (ROIs) with compensation of pelvic pose. The APP defined from these landmarks was quantitatively compared to the APPs determined by an expert and an unskilled. Intraobserver reliability was measured to evaluate the time-interval variability. Finally, we evaluate the robustness of this method to patient posture using an arbitrarily rotated volume. The intraclass correlation coefficients (ICCs) were calculated to determine the interobserver and intraobserver reliabilities. RESULTS: The ICC values for the four landmarks and the APP were similar between the semiautomated method and expert determination (ICC >0.937). The ICC values for intraobserver reliability over time for our method were all 1, demonstrating high reliability. Furthermore, agreement between the parameters determined from the original volume and the rotated volume was nearly perfect. CONCLUSIONS: Our method is a useful measurement tool for the APP as it is robust, and the results were similar to an experienced surgeon's determination. Furthermore, it was independent to the direction of the CT slice and more robust than a measurement by an unskilled.

Effect of dual treatment with SDF-1 and BMP-2 on ectopic and orthotopic bone formation.

PURPOSES: The potent stem cell homing factor stromal cell-derived factor-1 (SDF-1) actively recruits mesenchymal stem cells from circulation and from local bone marrow. It is well established that bone morphogenetic protein-2 (BMP-2) induces ectopic and orthotopic bone formation. However, the exact synergistic effects of BMP-2 and SDF-1 in ectopic and orthotopic bone regeneration models have not been fully investigated. The purpose of this study was to evaluate the potential effects of simultaneous SDF-1 and BMP-2 treatment on bone formation. MATERIALS AND METHODS: Various doses of SDF-1 were loaded onto collagen sponges with or without BMP-2.These sponges were implanted into subcutaneous pockets and critical-size calvarial defects in C57BL/6 mice. The specimens were harvested 4 weeks post-surgery and the degree of bone formation in specimens was evaluated by histomorphometric and radiographic density analyses. Osteogenic potential and migration capacity of mesenchymal cells and capillary tube formation of endothelial cells following dual treatment with SDF-1 and BMP-2 were evaluated with in vitro assays. RESULTS: SDF-1-only-treated implants did not yield significant in vivo bone formation and SDF-1 treatment did not enhance BMP-2-induced ectopic and orthotopic bone regeneration. In vitro experiments showed that concomitant use of BMP-2 and SDF-1 had no additive effect on osteoblastic differentiation, cell migration or angiogenesis compared to BMP-2 or SDF-1 treatment alone. CONCLUSIONS: These findings imply that sequence-controlled application of SDF-1 and BMP-2 must be further investigated for the enhancement of robust osteogenesis in bone defects.

PolyQ-dependent RNA-protein assemblies control symmetry breaking.

Dendritic growth in fungi and neurons requires that multiple axes of polarity are established and maintained within the same cytoplasm. We have discovered that transcripts encoding key polarity factors including a formin, Bni1, and a polarisome scaffold, Spa2, are nonrandomly clustered in the cytosol to initiate and maintain sites of polarized growth in the fungus Ashbya gossypii. This asymmetric distribution requires the mRNAs to interact with a polyQ-containing protein, Whi3, and a Pumilio protein with a low-complexity sequence, Puf2. Cells lacking Whi3 or Puf2 had severe defects in establishing new sites of polarity and failed to localize Bni1 protein. Interaction of mRNAs with Whi3 and Puf2 promotes enrichment of transcripts at established sites of polarized growth and clustering of polarity transcripts throughout the cell body. Thus, aggregation-prone proteins make functional assemblies to position polarity transcripts, and nonrandom positioning of transcripts is required for symmetry-breaking events. This reveals a physiological function for polyQ-driven assemblies in regulating cell polarity.

Ploidy variation in multinucleate cells changes under stress.

Ploidy variation is found in contexts as diverse as solid tumors, drug resistance in fungal infection, and normal development. Altering chromosome or genome copy number supports adaptation to fluctuating environments but is also associated with fitness defects attributed to protein imbalances. Both aneuploidy and polyploidy can arise from multinucleate states after failed cytokinesis or cell fusion. The consequences of ploidy variation in syncytia are difficult to predict because protein imbalances are theoretically buffered by a common cytoplasm. We examined ploidy in a naturally multinucleate fungus, Ashbya gossypii. Using integrated lac operator arrays, we found that chromosome number varies substantially among nuclei sharing a common cytoplasm. Populations of nuclei range from 1N to >4N, with different polyploidies in the same cell and low levels of aneuploidy. The degree of ploidy variation increases as cells age. In response to cellular stress, polyploid nuclei diminish and haploid nuclei predominate. These data suggest that mixed ploidy is tolerated in these syncytia; however, there may be costs associated with variation as stress homogenizes the genome content of nuclei. Furthermore, the results suggest that sharing of gene products is limited, and thus there is incomplete buffering of ploidy variation despite a common cytosol.

Arthroscopic treatment of synovial chondromatosis of the hip.

BACKGROUND: Recently, arthroscopic loose body removal and synovectomy have been performed as treatments for synovial chondromatosis of the hip joint. However, to date, no reports have been published on the outcomes of arthroscopic treatments. HYPOTHESIS: Arthroscopic treatment is effective for synovial chondromatosis of the hip joint and has advantages such as low recurrence rates, faster return to activities of daily life, and few surgical complications. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: From June 1996 to July 2008, 24 patients with synovial chondromatosis of the hip who were followed up after arthroscopic removal of loose bodies and synovectomy were evaluated. The common arthroscopic portals were the anterior, anterolateral, and posterolateral portals. In some cases, we applied a medial portal for removal of loose bodies in the posteromedial pouch. Preoperative and postoperative assessments were made through simple radiographs, 3-dimensional computed tomography, magnetic resonance imaging, visual analog scale (VAS) for pain, range of motion of the joint, Harris Hip Score, and Merle D'Aubigné and Postel score. RESULTS: Postoperative mean follow-up period was 41 months. There were no major complications. Patients were able to walk weightbearing on average 2 days after surgery and were discharged in an average of 3.5 days (range, 3-5 days) after surgery. In postoperative radiological imaging, 4 patients showed progression of joint osteoarthritis, and 1 of them underwent total hip arthroplasty. The VAS score before surgery was 8.1 ± 1.3 and after surgery was 3.1 ± 1.4. Range of motion of the hip joint before surgery was increased after surgery, except in 1 patient who required a third operation. Harris Hip Score before surgery was an average of 39 ± 6.9 and improved to an average of 82 ± 10.2 after surgery. Eighteen patients (75%) had good or excellent outcomes. Symptomatic disease recurred in 4 patients (16.7%), and 1 of these 4 patients showed a subsequent recurrence. CONCLUSION: The treatment of synovial chondromatosis of the hip using arthroscopic loose body removal and synovectomy is relatively successful, and rehabilitation of patients is fast, therefore making it an effective treatment with satisfactory postsurgical results. However, a technical limitation of arthroscopy is the difficulty in approaching the posterolateral and posteromedial areas of the peripheral compartment.

Influence of femoroacetabular impingement on results of hip arthroscopy in patients with early osteoarthritis.

To ascertain whether better results could be obtained using hip arthroscopy, we retrospectively reviewed the radiographic and clinical aspects of anterior femoroacetabular impingement in 43 patients diagnosed with early osteoarthritis with acetabular labral tears who previously had arthroscopic treatment. The average followup was 50 months. The patients were divided into two groups: patients who had no osteoarthritis seen on simple radiographs, but had degenerative changes of the labrum and cartilage seen on magnetic resonance arthrograms and arthroscopy, and patients who had osteoarthritic findings seen on simple radiographs. Both groups were examined retrospectively for signs of anterior femoroacetabular impingement at the acetabulum and proximal femur. Postoperative improvement was evaluated using the Japanese Orthopaedic Association pain score. Six of 21 patients in Group I and 12 of 22 of patients in Group II showed radiographic evidence of femoroacetabular impingement. The score improved from 0.76 preoperatively to 2.38 postoperatively in Group I and from 0.75 preoperatively to 1.90 postoperatively in Group II. Arthroscopic débridement produced improved results seen during short-term and midterm followups. However, in patients with femoroacetabular impingement the results were considered inadequate. We found that arthroscopic treatment of osteoarthritis of the hip fails if there is detectable femoroacetabular impingement.