AuFe3@Pd/γ-Fe2O3 Nanosheets as an In Situ Regenerable and Highly Efficient Hydrogenation Catalyst.

Heterogenous Pd catalysts play a pivotal role in the chemical industry; however, it is plagued by S2- or other strong adsorbates inducing surface poisoning long term. Herein, we report the development of AuFe3@Pd/γ-Fe2O3 nanosheets (NSs) as an in situ regenerable and highly active hydrogenation catalyst. Upon poisoning, the Pd monolayer sites could be fully and oxidatively regenerated under ambient conditions, which is initiated by •OH radicals from surface defect/FeTetra vacancy-rich γ-Fe2O3 NSs via the Fenton-like pathway. Both experimental and theoretical analyses demonstrate that for the electronic and geometric effect, the 2-3 nm AuFe3 intermetallic nanocluster core promotes the adsorption of reactant onto Pd sites; in addition, it lowers Pd's affinity for •OH radicals to enhance their stability during oxidative regeneration. When packed into a quartz sand fixed-bed catalyst column, the AuFe3@Pd/γ-Fe2O3 NSs are highly active in hydrogenating the carbon-halogen bond, which comprises a crucial step for the removal of micropollutants in drinking water and recovery of resources from heavily polluted wastewater, and withstand ten rounds of regeneration. By maximizing the use of ultrathin metal oxide NSs and intermetallic nanocluster and monolayer Pd, the current study demonstrates a comprehensive strategy for developing sustainable Pd catalysts for liquid catalysis.

Challenges in the modification of the M1 stage of the TNM staging system for nasopharyngeal carcinoma: A study of 1027 cases and review of the literature.

A series of modifications have been introduced to the TNM staging system over time for nasopharyngeal carcinoma (NPC), mainly focused on the T (primary tumor) and N (local node) components of the system. The M1 stage is a 'catch all' classification, covering a group of patients whose outlook ranges from potentially curable to incurable. Since the current M1 stage does not allow clinicians to stratify patients according to prognosis or guide therapeutic decision-making and allow comparison of results of radical and non-radical treatments, we aimed to subdivide the M1 stage according to a retrospective study of 1027 metastatic NPC patients and to review the relevant literature. Between 1995 and 2007, 1027 inpatients with distant metastasis from NPC were retrospectively analyzed. Various possible subdivisions of the M1 stage were considered, looking at different metastatic sites, the number of metastatic organs and the number of metastases. Survival rates were calculated using the Kaplan-Meier method and compared using the log-rank test. The most frequently involved metastatic sites were the bone, lung and liver. The incidence rates of solitary metastatic lesions and pulmonary metastasis were 16.2 and 41.3%. Despite the poor survival of these patients with a median survival of 30.8 months, patients in the metachronous metastatic group with metastases to the lung and/or solitary lesions, were defined as M1a, and were significantly associated with favorable median survival of 41.5 and 49.1 months in the univariate and multivariate analysis, respectively. Patients in the metachronous metastatic group with metastasis to the lung and/or solitary lesions (M1a) have a more favorable prognosis compared with those patients with multiple metastases located in other anatomic sites (M1b). These data, in one of the largest reported metastatic NPC cohorts, are the first to show the prognostic impact of metastatic status in NPC. As a powerful predictor, the potential clinical value of a modified M1 of the TNM system for NPC will facilitate patient counseling and individualize management.

Comparative serum proteomic analysis involving liver organ-specific metastasis-associated proteins of nasopharyngeal carcinoma.

Metastasis is the main cause of cancer-related mortality; patients with liver metastases (LM) have the worst prognosis among patients with nasopharyngeal carcinoma (NPC). However, at present, few biomarkers for detecting organ-specific metastasis have been identified. Proteomics, an ultra-sensitive analytical technique, can detect molecular changes before organ-specific metastasis occurs. Analysis with matrix-assisted, laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS), combined with magnetic chemical affinity beads is a new technique for evaluating protein separation. We sought to identify potential liver-specific, metastasis-associated proteomic printing in patients with NPC. We examined 64 serum samples from 50 patients who had pathologically confirmed NPC and 14 who had pathologically confirmed non-NPC with LM using MALDI-TOF-MS with weak cation bead protein chips. During follow-up of at least 37 months (maximum, 176 months) following radiotherapy, we confirmed 16 cases of LM (LM NPC), 16 cases without LM (non-LM NPC) and 18 cases without metastasis (non-M NPC). Using comparison analysis, 4 protein mass peaks, 4155.34, 4194.87, 4210.78 and 4249.56 m/z were identified as liver-specific, metastasis-associated protein peaks in NPC and two of them (4155 and 4249 m/z) met two different statistical criteria in both ClinProt software analyses and discriminant analyses. Models based on the 4 potential serum markers of NPC discriminated between LM NPC, non-LM NPC, non-M NPC and non-NPC LM analyzed with sieved markers. The recognition capability and cross-validation of these models for differentiating the above 4 groups are all approximately 80%. MALDI-TOF-MS combined with tree analysis models may provide a clinical diagnostic platform for detecting potential liver-specific, metastasis-associated proteomic printing in NPC. However, markedly differential proteins still need to be identified.