Many-Scale Investigations of the Deformation Behavior of Polycrystalline Composites: I—Machine Learning Applied for Image Segmentation

Our work investigates the polycrystalline composite deformation behavior through multiscale simulations with experimental data at hand. Since deformation mechanisms on the micro-level link the ones on the macro-level and the nanoscale, it is preferable to perform micromechanical finite element simulations based on real microstructures. The image segmentation is a necessary step for the meshing. Our 2D EBSD images contain at least a few hundred grains. Machine learning (ML) was adopted to automatically identify subregions, i.e., individual grains, to improve local feature extraction efficiency and accuracy. Denoising in preprocessing and postprocessing before and after ML, respectively, is beneficial in high quality feature identification. The ML algorithms used were self-developed with the usage of inherent code packages (Python). The performances of the three supervised ML models—decision tree, random forest, and support vector machine—are compared herein; the latter two achieved accuracies of up to 99.8%. Calculations took about 0.5 h from the original input dataset (EBSD image) to the final output (segmented image) running on a personal computer (CPU: 3.6 GHz). For a realizable manual pixel sortation, the original image was firstly scaled from the initial resolution 10802 pixels down to 3002. After ML, some manual work was necessary due to the remaining noises to achieve the final image status ready for meshing. The ML process, including this manual work time, improved efficiency by a factor of about 24 compared to a purely manual process. Simultaneously, ML minimized the geometrical deviation between the identified and original features, since it used the original resolution. For serial work, the time efficiency would be enhanced multiplicatively.     

Robotic-Assisted Laparoscopic vs Abdominal and Laparoscopic Myomectomy: Systematic Review and Meta-Analysis

Herein is presented a systematic review and meta-analysis of evidence related to operative outcomes associated with robotic-assisted laparoscopic myomectomy (RLM) compared with abdominal myomectomy (AM) and laparoscopic myomectomy (LM). Outcome measures included estimated blood loss (EBL), blood transfusion, operating time, complications, length of hospital stay (LOHS), and costs. Meta-analysis 1 compared RLM vs AM, and meta-analysis 2 compared RLM vs LM. Studies scored moderately well on the Newcastle-Ottawa Quality Assessment Scale. No significant differences were found in age, body mass index, or number, diameter, and weight of myomas. In meta-analysis 1, EBL, blood transfusion, and LOHS were significantly lower; risk of complications was similar; and operating time and costs were significantly higher with RLM. In meta-analysis 2, no significant differences were noted in EBL, operating time, complications, and LOHS with RLM; however, blood transfusion risk and costs were higher. It was concluded that insofar as operative outcomes, RLM has significant short-term benefits compared with AM and no benefits compared with LM. Long-term benefits such as recurrence, fertility, and obstetric outcomes remain uncertain.     

Automated Computational Detection of Interstitial Fibrosis,Tubular Atrophy,and Glomerulosclerosis

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De novo leukocyte chemotactic factor 2 amyloidosis in a pediatric renal allograft, 15 years post‐transplant

Leukocyte chemotactic factor 2 amyloidosis (ALECT2) is a recently described form of systemic amyloidosis, which most commonly affects the kidney and liver. The LECT2 protein is produced during inflammatory processes, but its precise function in renal diseases in unclear. ALECT2, however, is known to be a relatively common form of renal amyloidosis, after amyloid light chain and serum amyloid A types and is most often seen in patients of Hispanic ethnicity. ALECT2 can occur de novo or as recurrent disease in kidney transplants. We present the first case, to our knowledge, of de novo ALECT2 in a pediatric kidney transplant patient, 15 years post‐transplant.     

Severe Renal Allograft Rejection Resulting from Lenalidomide Therapy for Multiple Myeloma: Case Report

Lenalidomide, a thalidomide analogue, is an immunomodulatory drug currently used as a chemotherapeutic agent in treating certain hematologic malignancies, including multiple myeloma. The antineoplastic effect of lenalidomide may be due to its ability to modulate different components of the immune system as well as its antiangiogenic, antiproliferative, and direct cytotoxic activity. Given its immunomodulatory effects, lenalidomide may potentially elicit unintended immune activity against allografts in solid organ transplant recipients. Here, we present a case of a renal transplant recipient who developed multiple myeloma after transplantation and was treated with the use of lenalidomide, which precipitated severe acute T-cell–mediated rejection. Lenalidomide was thought to be causative, and after cessation of the drug her renal function stabilized.     

A retrospective observational study of benign anthracotic lymphadenitis and its association with PET avid lymph nodes in patients undergoing cancer evaluation

BackgroundAccurate staging of newly diagnosed or recurrent malignancy is essential for effective treatment. An important first step in staging involves the use of PET/CT to identify areas of FDG avidity. PET/CT however has limitations, including false positive FDG uptake from benign causes. In this paper we characterize an uncommon yet clinically important cause of false positive PET/CTs, that of benign anthracotic lymphadenitis (BAL). We examine the clinical, radiographic and histologic characteristics of BAL in patients referred for endobronchial ultrasound (EBUS) guided biopsies and discuss its context in relation to existing literature.MethodsWe performed a retrospective observational case series of 20 patients who were referred for EBUS guided biopsies of PET positive mediastinal and hilar lymph nodes during the work-up or treatment of suspected malignancy.ResultsTo be included, all patients received PET imaging as well as an EBUS guided biopsy of FDG avid lymph nodes which demonstrated anthracotic pigment as the only histologic abnormality. The key findings were that 90% of patients in this cohort were born outside of the US, 90% had bilateral FDG avid lymph nodes with an average standardized uptake value (SUV) of 7.9±2.2. Most patients, based on their history, had a likely exposure to biomass fuel or urban pollution.ConclusionsBAL may be an underrecognized cause for PET positive lymph nodes in patients undergoing work-up for malignancy. These findings support the importance of sampling mediastinal and hilar lymph nodes even when SUVs are highly suggestive of malignancy.