Variant histology is associated with more non-urothelial tract recurrence but less intravesical recurrence for upper tract urothelial carcinoma after radical nephroureterectomy.

PURPOSE: To investigate the prognostic impact of variant histology (VH) on oncological outcomes in patients with upper urinary tract urothelial carcinoma (UTUC) who had undergone radical nephroureterectomy (RNU). PATIENTS AND METHODS: A total of 1239 patients with clinically localized UTUC who underwent RNU at a single institution between January 2005 and June 2020 were included. The VH was reviewed by a uro-pathologist at our institution. The Cox regression model was used to perform multivariate analysis, including VH and other established prognostic factors for post-RNU oncological outcomes (intravesical recurrence [IVR], non-urothelial recurrence, and cancer-specific death). RESULTS: Of the 1239 patients with UTUC, 384 patients (31%) were found to have VH. Advanced tumor stage, lymph node metastasis, high tumor grade, lymphovascular invasion, open surgery, and renal pelvis had a significantly larger proportion of UTUC with VH compared to pure UTUC (all p < 0.05). VH was an independent prognostic factor associated with less IVR identified by multivariate analysis, more non-urothelial recurrence, and more cancer-specific mortality. CONCLUSION: Patients with VH account for 31% with UTUC treated with RNU in this cohort. VH was an independent prognostic factor associated with more non-urothelial recurrence and cancer-specific mortality but less IVR.

Spiro-Twisted Benzoxazine Derivatives Bearing Nitrile Group for All-Solid-State Polymer Electrolytes in Lithium Batteries.

In this study, two nitrile-functionalized spiro-twisted benzoxazine monomers, namely 2,2'-((6,6,6',6'-tetramethyl-6,6',7,7'-tetrahydro-2H,2'H-8,8'-spirobi[indeno[5,6-e][1,3]oxazin]-3,3'(4H,4'H)-diyl)bis(4,1-phenylene))diacetonitrile (TSBZBC) and 4,4'-(6,6,6',6'-tetramethyl-6,6',7,7'-tetrahydro-2H,2'H-8,8'-spirobi[indeno[5,6-e][1,3]oxazin]-3,3'(4H,4'H)-diyl)dibenzonitrile (TSBZBN) were successfully developed as cross-linkable precursors. In addition, the incorporation of the nitrile group by covalent bonding onto the crosslinked spiro-twisted molecular chains improve the miscibility of SPE membranes with lithium salts while maintaining good mechanical properties. Owing to the presence of a high fractional free volume of spiro-twisted matrix, the -CN groups would have more space for rotation and vibration to assist lithium migration, especially for the benzyl cyanide-containing SPE. When combined with poly (ethylene oxide) (PEO) electrolytes, a new type of CN-containing semi-interpenetrating polymer networks for solid polymer electrolytes (SPEs) were prepared. The PEO-TSBZBC and PEO-TSBZBN composite SPEs (with 20 wt% crosslinked structure in the polymer) are denoted as the BC20 and BN20, respectively. The BC20 sample exhibited an ionic conductivity (σ) of 3.23 × 10-4 S cm-1 at 80 °C and a Li+ ion transference number of 0.187. The LiFePO4 (LFP)|BC20|Li sample exhibited a satisfactory charge-discharge capacity of 163.6 mAh g-1 at 0.1 C (with approximately 100% coulombic efficiency). Furthermore, the Li|BC20|Li cell was more stable during the Li plating/stripping process than the Li|BN20|Li and Li|PEO|Li samples. The Li|BC20|Li symmetric cell could be cycled continuously for more than 2700 h without short-circuiting. In addition, the specific capacity of the LFP|BC20|Li cell retained 87% of the original value after 50 cycles.

Epoxy-Based Interlocking Membranes for All Solid-State Lithium Ion Batteries: The Effects of Amine Curing Agents on Electrochemical Properties.

In this study, a series of crosslinked membranes were prepared as solid polymer electrolytes (SPEs) for all-solid-state lithium ion batteries (ASSLIBs). An epoxy-containing copolymer (glycidyl methacrylate-co-poly(ethylene glycol) methyl ether methacrylate, PGA) and two amine curing agents, linear Jeffamine ED2003 and hyperbranched polyethyleneimine (PEI), were utilized to prepare SPEs with various crosslinking degrees. The PGA/polyethylene oxide (PEO) blends were cured by ED2003 and PEI to obtain slightly and heavily crosslinked structures, respectively. For further optimizing the interfacial and the electrochemical properties, an interlocking bilayer membrane based on overlapping and subsequent curing of PGA/PEO/ED2003 and PEO/PEI layers was developed. The presence of this amino/epoxy network can inhibit PEO crystallinity and maintain the dimensional stability of membranes. For the slightly crosslinked PGA/PEO/ED2003 membrane, an ionic conductivity of 5.61 × 10-4 S cm-1 and a lithium ion transference number (tLi+) of 0.43 were obtained, along with a specific capacity of 156 mAh g-1 (0.05 C) acquired from an assembled half-cell battery. However, the capacity retention retained only 54% after 100 cycles (0.2 C, 80 °C), possibly because the PEO-based electrolyte was inclined to recrystallize after long term thermal treatment. On the other hand, the highly crosslinked PGA/PEO/PEI membrane exhibited a similar ionic conductivity of 3.44 × 10-4 S cm-1 and a tLi+ of 0.52. Yet, poor interfacial adhesion between the membrane and the cathode brought about a low specific capacity of 48 mAh g-1. For the reinforced interlocking bilayer membrane, an ionic conductivity of 3.24 × 10-4 S cm-1 and a tLi+ of 0.42 could be achieved. Moreover, the capacity retention reached as high as 80% after 100 cycles (0.2 C, 80 °C). This is because the presence of the epoxy-based interlocking bilayer structure can block the pathway of lithium dendrite puncture effectively. We demonstrate that the unique interlocking bilayer structure is capable of offering a new approach to fabricate a robust SPE for ASSLIBs.