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Tungsten and molybdenum ores have abundant paragenesis or associated elements. Detection of these elements is beneficial to the comprehensive utilization of mineral resources. At present, the contents of these elements are detected respectively by the national standard method of tungsten ore and molybdenum ore, which has a low efficiency. A method for the determination of trace elements in tungsten ore and molybdenum ore by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) is proposed. Tungsten ore and molybdenum ore samples were dissolved by HCl-HNO3-HF-HClO4 at normal pressure and extracted by hydrochloric acid (7% of HCl). The 10 trace elements of Bi, Co, Cu, Li, Ni, P, Pb, Sr, V and Zn were simultaneously measured by ICP-AES. Analytical wavelength and spectral level of elements were selected. The background interferences were eliminated with an off-peak background correction method，and the spectral overlapping interferences between elements were eliminated using an interference elements correction coefficients method．The detection limits were 1.43-18.8 μg/g and the recovery rates were 90%-110%. This method has been applied to the determination of tungsten ore and molybdenum ore national certified reference materials, and the results were in good agreement with the certified values with RSD (n=10) 1ess than 8%. The method avoided the influence of adding a large amount of alkali metal elements and probably foreign matter with alkali fusion, without precipitation processing of tungstic acid and molybdic acid. It can be used to rapidly determine paragenesis or associated elements in tungsten ore and molybdenum ore.

Aim: To evaluate the methodology, feasibility, safety and efficacy of a novel method called cap-assisted endoscopic sclerotherapy (CAES) for internal hemorrhoids., Methods: A pilot study on CAES for grade I to III internal hemorrhoids was performed. Colon and terminal ileum examination by colonoscopy was performed for all patients before starting CAES. Polypectomy and excision of anal papilla fibroma were performed if polyps or anal papilla fibroma were found and assessed to be suitable for resection under endoscopy. CAES was performed based on the requirement of the cap, endoscope, disposable endoscopic long injection needle, enough insufflated air and sclerosing agent., Results: A total of 30 patients with grade I to III internal hemorrhoids was included. The follow-up was more than four weeks. No bleeding was observed after CAES. One (3.33%) patient claimed mild tenesmus within four days after CAES in that an endoscopist performed this procedure for the first time. One hundred percent of patients were satisfied with this novel procedure, especially for those patients who underwent CAES in conjunction with polypectomy or excision of anal papilla fibroma., Conclusion: CAES as a novel endoscopic sclerotherapy should be a convenient, safe and effective flexible endoscopic therapy for internal hemorrhoids.

Aim: To investigate the effect of gambogic acid (GA) on apoptosis in the HT-29 human colon cancer cell line., Methods: H-29 cells were used for in vitro experiments in this study. Relative cell viability was assessed using MTT assays. Cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling and Hoechst 33342 staining, and quantified by flow cytometry. Cellular ultrastructure was observed by transmission electron microscopy. Real-time PCR and Western blot analyses were used to evaluate gene and protein expression levels. For in vivo experiments, BALB/c nude mice received subcutaneous injections of HT-29 cells in the right armpit. When well-established xenografts were palpable with a tumor size of 75 mm(3), mice were randomly assigned to a vehicle (negative) control, positive control or GA treatment group (n = 6 each). The animals in the treatment group received one of three dosages of GA (in saline; 5, 10 or 20 mg/kg) via the caudal vein twice weekly, whereas animals in the negative and positive control groups were given equal volumes of 0.9% saline or 10 mg/kg docetaxel, respectively, via the caudal vein once weekly., Results: The cell viability assay showed that GA inhibited proliferation of HT-29 cells in a dose- and time-dependent manner after treatment with GA (0.00, 0.31, 0.62, 1.25, 2.50, 5.00 or 10.00 μmol/L) for 24, 48 or 72 h. After 48 h, the percentage of apoptotic cells in cells treated with 0.00, 1.25, 2.50 and 5.00 μmol/L GA was 1.4% ± 0.3%, 9.8% ± 1.2%, 25.7% ± 3.3% and 49.3% ± 5.8%, respectively. Ultrastructural analysis of HT-29 cells treated for 48 h with 2.5 μmol/L GA revealed apoptotic bodies and condensed and fragmented nuclei. Levels of caspase-8, -9 and -3 mRNAs were significantly increased after treatment with GA (1.25, 2.50 or 5.00 μmol/L) for 48 h (P < 0.05 for all). Protein levels of apoptosis-related factors Fas, FasL, FADD, cytochrome c, and Apaf-1 were increased in GA-treated cells, whereas levels of pro-caspase-8, -9 and -3 were significantly decreased (P < 0.05 for all). Furthermore, GA significantly and dose-dependently inhibited the growth of HT-29 tumors in a mouse xenograft model (P < 0.05)., Conclusion: GA inhibits HT-29 proliferation via induction of apoptosis. The anti-cancer effects are likely mediated by death receptor (extrinsic) and mitochondrial (intrinsic) pathways.