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The effects of W powder particle size, complexing agent, W powder loading on the electroless Ni plating on the surface of W powder are analyzed, and the morphology of coated particle, utilization rate of Ni and deposition rate are investigated. The controllable electroless Ni plating process parameters are optimized. The Ni-coated W powders are mixed with Cu powders, and then the mixed powders are sintered to prepare 67W-25Cu-8Ni alloy by using spark plasma sintering (SPS) technique. 67W-25Cu-8Ni alloy is analyzed by scanning electric microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) . Results show that, when W powder particle size is in range from 4 µm to 6 µm, the complexing agent of sodium pyrophosphate is 60 g/L, triethanolamine is 100 g/L, and trisodium citrate is 8 g/L. The Ni layer is uniform and complete, and the weight percent of Ni in W-Ni powder can be controlled by adjusting the W powder loading. Metallurgical bonding is achieved at the W/Ni/Cu interface. Compared with W-Cu alloy, the sintering density of 67W-25Cu-8Ni alloy prepared by SPS is greatly increased, reaching to 97%. [ABSTRACT FROM AUTHOR]

Purpose The European Neuroendocrine Tumor Society (ENETS) and the American Joint Committee on Cancer (AJCC) staging classifications are two widely used systems in managing pancreatic neuroendocrine tumors. However, there is no universally accepted system. Methods An analysis was performed to evaluate the application of the ENETS and AJCC staging classifications using the SEER registry (N = 2,529 patients) and a multicentric series (N = 1,143 patients). A modified system was proposed based on analysis of the two existing classifications. The modified system was then validated. Results The proportion of patients with AJCC stage III disease was extremely low for both the SEER series (2.2%) and the multicentric series (2.1%). For the ENETS staging system, patients with stage I disease had a similar prognosis to patients with stage IIA disease, and patients with stage IIIB disease had a lower hazard ratio for death than did patients with stage IIIA disease. We modified the ENETS staging classification by maintaining the ENETS T, N, and M definitions and adopting the AJCC staging definitions. The proportion of patients with stage III disease using the modified ENETS (mENETS) system was higher than that of the AJCC system in both the SEER series (8.9% v 2.2%) and the multicentric series (11.6% v 2.1%). In addition, the hazard ratio of death for patients with stage III disease was higher than that for patients with stage IIB disease. Moreover, statistical significance and proportional distribution were observed in the mENETS staging classification. Conclusion An mENETS staging classification is more suitable for pancreatic neuroendocrine tumors than either the AJCC or ENETS systems and can be adopted in clinical practice.

Objective: To study the cardiovascular effect of selective orexin-1 receptor (OX1R) antagonist SB408124 in anesthetized rats and explore the underlying mechanism by using intracerebroventricular (ICV) microinjection combined with immunohistochemical assay., Methods: The changes of mean arterial blood pressure (MAP) and heart rate (HR) of male Sprague-Dawley rats were recorded during ICV microinjection of SB408124 with or without pretreatment of atropine methyl nitrate or hexamethonium bromide. Furthermore, tyrosine hydroxylase (TH) immunopositive neurons in the rostral ventrolateral medulla (RVLM) of the rat were detected with immunohistochemical assay after ICV microinjection of SB408124., Results: ICV administration of SB408124 resulted in a significant decrease in MAP in anesthetized rats, which was accompanied with a mild decrease in HR. The cardiovascular responses elicited by SB408124 were not abolished by pretreatment of atropine methyl nitrate whereas fully abolished by pretreatment of hexamethonium bromide. The number of TH-immunopositive neurons in rat RVLM were significantly decreased following ICV administration of SB408124., Conclusion: ICV microinjection of selective OX1R antagonist SB408124 can cause decreases of MAP and HR mediated by inhibiting sympathetic activity in anesthetized rats.