As an emerging class of highly and hierarchically porous materials with continuous conductive metal network backbones, metal aerogels have unleashed tremendous potential in various fields, especially in electrocatalysis. However, it remains a great challenge to maximize the utilization of the intrinsic structural advantages of metal aerogels due to the collapse of their structure during conventional electrode preparation caused by their brittle character. Herein, a general in situ silicone‐confined gelation strategy is developed to integrate metal aerogels (PtPd, PtAg, PdAg, and AuAg) into/onto macroporous skeletons (carbon cloth, carbon fiber foam, and nickel foam). The composite materials have good mechanical flexibility, and can be utilized directly under the condition of well‐preserved intrinsic structure of metal aerogels. This not only results in more efficient electron transfer and faster mass transport, but also eliminates Ostwald ripening and aggregation, leading to both remarkably enhanced activity and durability when compared to that made by conventional ink drop coating with collapsed and compressed structure. This work represents a significant breakthrough for metal aerogels, and provides inspiration for electrocatalyst design with both high activity and durability.

Ependymoma with cartilaginous metaplasia with or without bone formation is exceedingly rare. Only eight cases have been reported in the literature. We report a case of ependymoma with cartilaginous and osseous metaplasia in a 5-year-old boy. Microscopically, the tumor was composed of neoplastic ependymal tissue and mature cartilage and bone. Immunohistochemically, glial fibrillary acidic protein and epithelial membrane antigen were positive for ependymoma cells but negative for cartilage and bone. Recurrence occurred after 15-month follow-up. The patient deteriorated rapidly and died after 1 month. Reviewing 8 reported cases and our latest case, we found that 3 cases of ependymoma with cartilaginous metaplasia were treated with radiotherapy. Six cases had recurrence from 6 months to 8 years and 2 cases died on the day of operation. These findings suggest that ependymoma with cartilaginous metaplasia might have more aggressive clinical behavior.

Developing efficient and stable Pt‐based oxygen reduction reaction (ORR) electrocatalysts via both economical and controllable routes is critical for the practical application of electrochemical energy devices. Herein, a scalable, controllable, and general ambient‐O2‐involved aqueous‐solution cultivating strategy to prepare PtxMy (M = Ni, Fe, Co) bunched‐nanocages aerogels (BNCs AG) is demonstrated, based on a newly established high‐M‐to‐Pt‐precursor‐ratio‐and‐B‐incorporation‐facilitated M‐rich core and Pt‐rich shell hydrogel formation process. The Pt83Ni17 BNCs AG shows prominent ORR performance with a mass activity (MA) of 1.95 A mgPt−1 and specific activity of 3.55 mA cm−2, which are 8.9‐times and 9.6‐times that of Pt supported on carbon (Pt/C), respectively. Particularly, the Pt83Ni17 BNCs AG displays greatly enhanced durability (MA 82.6% retention) compared to Pt/C (MA 31.8% retention) after a 20 000‐cycles accelerated durability test. Systematic studies including density functional theory calculations uncover that the excellent activity is closely related to the optimized ligand and strain effects with the optimized Ni content in this aerogel; the outstanding durability is endowed by the lowered‐down Ni leaching with the optimized Pt/Ni ratio and the inhibited sintering due to its appropriate porosity. This work provides new perspectives on the development of electrocatalysts with both high performance and low cost.

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Aim of the studyTo determine the significance of expression of synaptophysin, chromogranin A, and Ki-67 and their association with clinicopathological parameters, and to find out the possible prognostic factors in gastric neuroendocrine carcinoma (G-NEC).Material and methodsWe investigated the immunohistochemical features and prognosis of 62 G-NECs, and evaluated the association among expressions of synaptophysin, chromogranin A, and Ki-67, clinicopathological variables, and outcome.ResultsChromogranin A expression was found more commonly in small-cell NECs (9/9, 100%) than in large-cell NECs (27/53, 51%) (p = 0.008). No statistical significance was found in Ki-67 (p = 0.494) or synaptophysin (p > 0.1) expression between NEC cell types. Correlation analyses revealed that Ki-67 expression was significantly associated with mid-third disease of stomach (p = 0.005) and vascular involvement (p = 0.006), and had a trend of significant correlation with tumour relapse (p = 0.078). High expression of chromogranin A was significantly associated with histology of small-cell NECs (p = 0.008) and lesser tumour greatest dimension (p = 0.038). The prognostic significance was determined by means of Kaplan-Meier survival estimates and log-rank tests, and as a result, early TNM staging and postoperative chemotherapy were found to be correlated with longer overall survival (p < 0.05). Univariate analysis revealed associations between poor prognosis in NECs and several factors, including high TNM staging (p = 0.048), vascular involvement (p = 0.023), relapse (p = 0.004), and microscopic/macroscopic residual tumour (R1/2, p < 0.001). In a multivariate analysis, relapse was identified as the sole independent prognostic factor.ConclusionsNo significant correlation between survival and expression of synaptophysin, chromogranin A, or Ki-67 has been determined in G-NECs. Our study indicated that early diagnosis, no-residual-tumour resection, and postoperative chemotherapy were possible prognostic factors.