Incorporation of nanosized calcium silicate improved osteointegration of polyetheretherketone under diabetic conditions

AUTHORS

Rui Ma, Yongwei Li, Jialin Wang, Pei Yang, Kunzheng Wang & Wei Wang

ABSTRACT

Diabetes can impair osteoblastic functions and negatively interfere with osteointegration at the bone/implant interface. Previously, we prepared a nanosized calcium silicate (CS) incorporated-polyetheretherketone (PK) biocomposite (CS/PK) and found that the CS/PK composite exhibited enhanced osteoblast functions in vitro and osteointegration in vivo, but its bioperformance under diabetic conditions remained elusive. In this study, MC3T3-E1 cells incubated on CS/PK and PK samples were subjected to diabetic serum (DS) and normal serum (NS); cell attachment, morphology, spreading, proliferation, and osteogenic differentiation were compared to assess in vitro osteoblastic functions on the surfaces of different materials. An in vivo test was performed on diabetic rabbits implanted with CS/PK or PK implants into the cranial bone defect to assess the osteointegration ability of the implants. In vitro results showed that diabetes inhibited osteoblastic functions evidenced by impaired morphology and spreading, and decreased attachment, proliferation, and osteogenic differentiation compared with the findings under normal conditions. Notably, CS/PK ameliorated osteoblastic disfunction under diabetic conditions in vitro. In vivo results from micro-CT and histologic examinations revealed that rabbits with CS/PK implants exhibited improved osteointegration at the bone/implant interface under diabetic conditions compared with PK. Therefore, the CS/PK composite improved the impaired osteointegration induced by diabetes and is a promising orthopedic or craniofacial implant material that may obtain good clinical performance in diabetic patients.

Incorporation of nanosized calcium silicate improved osteointegration of polyetheretherketone under diabetic conditions

Diabetes can impair osteoblastic functions and negatively interfere with osteointegration at the bone/implant interface. Previously, we prepared a nanosized calcium silicate (CS) incorporated-polyetheretherketone (PK) biocomposite (CS/PK) and found that the CS/PK composite exhibited enhanced osteoblast functions in vitro and osteointegration in vivo, but its bioperformance under diabetic conditions remained elusive.

High-Grade Uterine Sarcoma with BCOR Internal Tandem Duplication Presenting With Total Uterine Inversion

AUTHORS

T J Greenwell, S Kumar, C Hysell

ABSTRACT

High-grade uterine sarcomas are rare mesenchymal tumors in which the underlying genetics of many have been recently elucidated. BCOR internal tandem duplications are present in a subset of high-grade uterine sarcomas. We report a diagnostically challenging case of a high-grade uterine sarcoma with a BCOR internal tandem duplication presenting with total uterine inversion. The case is that of a 24 year old G0P0 female with a four month history of intermittent diffuse abdominal pain and abnormal uterine bleeding. Pelvic examination revealed a mass protruding to the hymenal ring. The patient was suspected of having a prolapsed fibroid through the cervix, and a myomectomy was planned. During the procedure, total uterine inversion was noted as a result of a submucosal mass emanating from the uterine apex. The mass was removed off a broad base using sharp dissection, and the uterus was reverted in a subsequent procedure. Grossly, the mass was polypoid, rubbery, and measured 7 cm in greatest dimension. It was grey-white to red-brown, variegated, and fibrotic with focal hemorrhagic areas.

Histologically, the neoplasm had variable cellularity with spindle cells and a myxoid background. There was diffuse mild to moderate cytologic atypia and areas of increased mitotic activity. Tongue-like growth was present at the interface of the tumor with the normal myometrium. The neoplastic cells showed strong immunoreactivity for cyclin D1, BCOR, and TRK. There was focal immunoreactivity for CD10, and ALK was negative. Next-generation sequencing was performed and demonstrated an insertion into the BCOR gene, consistent with a diagnosis of high- grade uterine sarcoma with BCOR internal tandem duplication. In conclusion, we report an interesting presentation of a high-grade uterine sarcoma with BCOR internal tandem duplication causing total uterine inversion. The morphologic features and immunohistochemical profile suggested the possibility of the entity, and next generation sequencing confirmed the diagnosis.

The effect of polyethylenglycol gel on the delivery and osteogenic differentiation of homologous tooth germ–derived stem cells in a porcine model

The aim of this study was to investigate if bone regeneration can be promoted by homologous transplantation of STRO-1 sorted (STRO-1+) porcine tooth germ mesenchymal stem cells (TGSCs) with the combination of polyethylenglycol (PEG)-based hydrogel and biphasic calcium phosphate (BCP) scaffolds.

Collagen XII mediated cellular and extracellular mechanisms regulate establishment of tendon structure and function

Tendons have a uniaxially aligned structure with a hierarchical organization of collagen fibrils crucial for tendon function. Collagen XII is expressed in tendons and has been implicated in the regulation of fibrillogenesis. It is a non-fibrillar collagen belonging to the Fibril-Associated Collagens with Interrupted Triple Helices (FACIT) family. Mutations in COL12A1 cause myopathic Ehlers Danlos Syndrome with a clinical phenotype involving both joints and tendons supporting critical role(s) for collagen XII in tendon development and function.

Anti‐Interleukin‐6 Therapy Decreases Hip Synovitis and Bone Resorption and Increases Bone Formation Following Ischemic Osteonecrosis of the Femoral Head

Legg‐Calvé‐Perthes disease (LCPD) is a juvenile form of ischemic femoral head osteonecrosis, which produces chronic hip synovitis, permanent femoral head deformity, and premature osteoarthritis. Currently, there is no medical therapy for LCPD. Interleukin‐6 (IL‐6) is significantly elevated in the synovial fluid of patients with LCPD. We hypothesize that IL‐6 elevation promotes chronic hip synovitis and impairs bone healing after ischemic osteonecrosis.