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Gut-dwelling Prevotella copri (P. copri), the most prevalent Prevotella species in the human gut, have been associated with diet and disease. However, our understanding of their diversity and function remains rudimentary because studies have been limited to 16S and metagenomic surveys and experiments using a single type strain. Here, we describe the genomic diversity of 83 P. copri isolates from 11 human donors. We demonstrate that genomically distinct isolates, which can be categorized into different P. copri complex clades, utilize defined sets of polysaccharides. These differences are exemplified by variations in susC genes involved in polysaccharide transport as well as polysaccharide utilization loci (PULs) that were predicted in part from genomic and metagenomic data. Functional validation of these PULs showed that P. copri isolates utilize distinct sets of polysaccharides from dietary plant, but not animal, sources. These findings reveal both genomic and functional differences in polysaccharide utilization across human intestinal P. copri strains., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Xanthomas are rare bone tumors that occur more often in the appendicular skeleton and typically appear radiographically benign, with a narrow zone of transition and a sclerotic rim. We report the case of a 57-year-old woman with hyperlipidemia presenting with bilateral shoulder pain after minor trauma. Radiographic and histopathologic investigation demonstrated intraosseous xanthoma with atypical features, including multifocality, a wide zone of transition and pathologic fractures-characteristics more commonly associated with aggressive lesions such as multiple myeloma or metastasis. The diagnosis, imaging, and histological appearance of xanthoma of bone are reviewed.

The purpose of this gallery of orthopedic implants was to provide a reference for emergency radiologists to quickly identify uncommon devices in the shoulders, hips, and extremities. The cases presented in this exhibit will include unusual arthroplasties and prostheses as well as bone graft implants (including allograft and autograft). Bone grafts are frequently used for the treatment of bone defects, which may be caused by trauma, infection, or avascularity. Autogenous cancellous, corticocancellous, or cortical bone grafts are often used, either free or vascularized. Alternative bone graft substitutes are also used. An obvious complication of bone grafts is the failure of incorporation. Joint arthroplasty is the most frequently performed orthopedic procedure after fracture fixation. Major indications include degenerative joint disease, inflammatory arthropathy, avascular necrosis, and complicated fractures. Custom orthopedic implants are frequently used for less common indications or for patients with bone tumors. The common hardware complications are infections, loosening, small particle disease/osteolysis, periprosthetic fracture, hardware fracture or dislocation, and recurrent disease, especially in patients with tumors. Many of the devices used by orthopedic surgeons are infrequently seen in everyday radiology practice. With such variations, correct recognition of the prosthetic devices and their complications is very important. The goal of this exhibit was to familiarize the radiologist with both the normal and abnormal appearance of many atypical orthopedic implants. It is important to understand the purpose and proper function of a device, but not necessarily important to describe every device by its proper brand name. Although this exhibit is not meant to be inclusive of every unusual orthopedic implant, we will present multiple examples of orthopedic hardware involving the shoulder, humerus, elbow, forearm, wrist, hand, pelvis, hip, femur, knee, tibia, ankle, and foot that are not likely seen in everyday practice.