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Category: Ankle Arthritis; Ankle Introduction/Purpose: Revision of failed total ankle replacement (TAR), such as in the setting of implant subsidence, aseptic loosening, or avascular necrosis (AVN) of the talus can be challenging and associated with increased morbidity. As TAR becomes a more commonly performed procedure in the treatment of end-stage ankle arthritis (ESAA), naturally there arises the need for revision options. In this case series, we describe the short-term clinical and radiographic outcomes of using a patient-specific custom 3D-printed total ankle total talus (TATR) prosthesis in the treatment of this unique subset of patients. Methods: 29 patients with ESAA who underwent TATR by a single surgeon at our institution from 2019 to 2022 were retrospectively identified. Average age was 61.3 (range, 39-77) years, with average follow-up of 22.5 (range, 12 to 57) months. All patients were indicated for revision of primary STAR implant (Stryker, Kalamazoo, MI) for failed TAR in the setting of aseptic loosening/subsidence and/or talar AVN. All patients underwent replacement with 3D-printed titanium implants based on preoperative CT analysis (Additive Orthopaedics, Little Silver, NJ). Custom components included a combined total talus and stemmed tibial component through an anterior approach (Figure). Pre- and postoperative patient-reported outcome were assessed using Patient Reported Outcomes Measurement Information System (PROMIS). Pre- and postoperative implant alignment was assessed using medial distal tibial angle (MDTA) and tibiotalar angle (TTA) on anteroposterior, and sagittal tibial angle (STA) on lateral weightbearing plain films. Incidence of revision and reoperations were recorded. Results: At final follow-up, all custom implants were intact without evidence of hardware failure or implant subsidence. There was significant improvement in all six PROMIS domains (Table). Two patients (6.9%) had postoperative complications; one patient underwent open reduction internal fixation of the tibia for a tibial periprosthetic fracture 1 month postoperatively, another patient underwent medial gutter debridement and tarsal tunnel release for recurrent pain 14 months postoperatively. There were no significant differences in pre- to postoperative radiographic coronal or sagittal alignment in terms of MDTA (88.4 vs 88.8), TTA (87.3 vs 88.0), or STA (85.1 vs 85.9). Conclusion: As ankle replacement becomes a more popular surgical treatment for ESAA, there is a growing need to identify durable revision solutions. This study demonstrates the promising utility of custom 3D-printed TATR in the setting of revision TAR. At short-term follow-up, there was significant improvement in pain and physical function, with an acceptable postoperative complication rate. While preliminary, custom 3D-printed TATR offer an alternative solution for a unique subset of patients where there are limited options available for revision following failed primary TAR. Further longer-term follow-up with a larger cohort is underway.

Abstract. Introduction:. Diffuse midline glioma with H3-K27M mutation is an infiltrative high-grade glioma, with predominantly astrocytic differentiation. Patient concerns:. A 54-year-old Chinese woman presented with memory loss for a month and walking instability for 15 days. Diagnosis:. Magnetic resonance imaging showed a mass shadow of isometric T1 and slightly longer T2 with mild mixed signals in the third ventricle of the suprasellar region. Histologically, the tumor was primarily sheet-like, with many “anucleate areas” composed of long and thin fibrillary processes of the bipolar cells, which formed “whorls.” The neoplastic nuclei were ovoid and moderate in size. The tumor showed brisk mitotic activity and vascular proliferation, with no necrosis. In addition to histone H3K27M mutation, immunohistochemical staining showed that the tumor cells were positive for glial fibrillary acidic protein, oligodendrocyte transcription factor 2, alpha-thalassemia/mental retardation syndrome X, S-100 and Vimentin. The “anucleate areas” were positive for glial fibrillary acidic protein and negative for synaptophysin. The Ki-67 proliferation index was about 10%. Molecular genetic analyses detected H3F3A K27M mutation, but no mutations in IDH1 or IDH2, TERT promoter mutations, MGMT promoter methylation, KIAA1549-BRAF fusion or deletion of 1p/19q were found. Based on these findings, the patient was diagnosed as diffuse midline glioma with H3-K27M mutation in the third ventricle, corresponding to WHO grade 4. Interventions:. A craniotomy with total excision of the tumor was performed. Outcomes:. After surgery, she was routinely treated with temozolomide for chemotherapy and synchronous radiotherapy. It has been 11 months now, and the patient is living well. Conclusion:. This case report provides information on the microscopic morphological features of diffuse midline glioma with H3K27M mutation, which can help pathologists to make a definitive diagnosis of this tumor.

A novel composite material (TD) composed of TS-1 microcrystalline and dendritic mesoporous silica nanospheres (DMSNs) was successfully prepared. The TD composite material had open pore structure and large specific surface area, which was conducive to the mass transfer of reactants and products. The Ti element in TS-1 could be used as an electron assistant, and the spillover d-electrons were conducive to the improvement of the sulfidation and dispersion of MoS2, thereby forming more type II MoS2 active phases. The incorporation of Ti could bring more Brønsted (B) and Lewis (L) acid, which was conducive to the hydrogenation pathway (HYD) selectivity (41.2%) of dibenzothiophene (DBT) hydrodesulfurization (HDS) and isomerization (ISO) route selectivity (21.9%) of 4,6-dimethyldibenzothiophene (4,6-DMDBT) HDS, thus improve the HDS activity of DBT and 4,6-DMDBT. NiMo/TD-70 (Aging temperature = 70 °C) had the best HDS activities of DBT (99.0%) and 4,6-DMDBT (93.7%) due to its large open pore structure, good acidity, suitable metal-support interaction (MSI) and perfect dispersion of the metallic active sites. [ABSTRACT FROM AUTHOR]

Ni2P supported catalysts exhibit high catalytic activities in hydrogenation reaction, of which the particle sizes of Ni2P active phases are the key influential factor. This research focus on the effect of chelators on the size of Ni2P particles over wrinkle silica nanoparticles (WSNs) by introducing chelating agents EDTA and NTA during impregnation process. The characterization results show that chelators modified catalysts possess smaller size of Ni2P particles than the unmodified Ni2P catalysts. Among all the synthesized catalysts, the EDTA modified Ni2PE(1.5)/WSNs catalyst possesses smallest average particle size of Ni2P, only 2.6 nm. Moreover, the Ni2P catalysts with the assistance of EDTA exhibits better catalytic activity than that of NTA under high reaction temperature, which can be ascribed to the strong bonding between EDTA and Ni. And the EDTA modified Ni2PE(1.5)/WSNs catalyst shows highest hydrogenation ability, almost reaching 100% decalin selectivity. [ABSTRACT FROM AUTHOR]