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CaO significantly influences the SNCR deNO x process. The adsorption and reaction mechanism of NH 3 + NO + O 2 system on the CaO surface were studied in this work. Results showed that NH 3 adsorbed onto the Lewis acid sites of CaO and the main ad-species were NH 2 and OH. With increased temperature, NH 2 dehydrogenation occurred and formed dinitride, which eventually desorbed as N 2 O; whereas OH reacted with H to form H 2 O. O 2 accelerated NH 3 conversion to NH 2 and oxidized dinitride. NO ad-species on the CaO surface were cis-dimer nitroso and monodentate nitrate. With increased temperature, cis-dimer nitroso decomposed and desorbed as NO, and monodentate nitrate eventually desorbed as N 2 O. O 2 had no influence on NO ad-species. When NH 3 and NO coexisted, they simultaneously adsorbed onto the CaO surface and formed the similar ad-species with their single adsorption. NO was reduced to N 2 by NH 2 , and the reaction followed Langmuir–Hinshelwood mechanism. NH 2 dissociation to dinitride simultaneously occurred with NO reduction in the NH 3 + NO system. In the NH 3 + NO + O 2 system, NH 3 conversion to NH 2 was determined by O 2 . The majority of NH 2 was oxidized by O 2 , and the remainder reacted with NO. NH 2 dissociation to dinitride was negligible in the presence of O 2 . [ABSTRACT FROM AUTHOR]

Highlights: [•] CaO catalyzes NH3 decomposition, NO reduction by NH3, and NH3 oxidation by O2. [•] NH3 dissociation to NH2 is the rate-controlling step of NH3 conversion. [•] NH3 conversion on the CaO surface is mainly influenced by O2. [•] The selectivity of NH3 conversion is influenced by both O2 and NO. [•] Mechanism and kinetic model are proposed to describe the CaO-involved SNCR process. [ABSTRACT FROM AUTHOR]

Theinfluence of Fe2O3on the SNCR deNOxprocess was investigated in a fixed-bedreactor. The experimental results demonstrated that Fe2O3has an inhibitory effect on the SNCR deNOxprocess that is more notable at low temperatures.Interactions between Fe2O3and NH3, Fe2O3-catalyzed NH3oxidation,and NO reduction by NH3were studied experimentally. Inthe absence of O2, Fe2O3was reducedby NH3to form Fe, which then catalyzed NH3decompositionto N2and H2. Fe2O3alsocatalyzed NO reduction by NH3. In the presence of O2, Fe2O3mainly catalyzed NH3oxidation. All reactions showed first-order characteristics withrespect to NH3, which indicates that the adsorption ofNH3and its dissociation into −NH2onthe surface of Fe2O3is the rate-controllingstep in these processes. The presence of O2and NO affectedthe selectivity of further −NH2reaction. A kineticmodel was developed, and the simulation results agreed well with theexperimental data. [ABSTRACT FROM AUTHOR]

Abstract Background  The nuclear factor kappa B (NF-κB) pathway is a critical mediator of regulated on activation, normal T cell expressed and secreted (RANTES) gene regulation and therefore represents a potential target for therapy of endometriosis-associated symptoms. Objective  The objective of this study was to investigate the effect of NF-κB decoy oligonucleotides (ODNs) on NF-κB activation, RANTES expression, and monocyte chemotactic activity in ectopic endometrial stromal cells in vitro. Methods  A specific sandwich enzyme-linked immunosorbent assay (ELISA) was used to quantify RANTES expression in ectopic and normal endometrial stromal cells stimulated by interleukin (IL)-1β. Four hours after transfection of NF-κB decoy ODNs, 10 ng/ml IL-1β was added to induce the ectopic endometrial stromal cells to secrete RANTES. The NF-κB activation, RANTES expression, and monocyte chemotactic activity in ectopic endometrial stromal cells were respectively evaluated by electrophoretic mobility shift assay, ELISA, and Boyden chambers. Results  IL-1β induced significantly higher levels (P P  Conclusions  NF-κB decoy ODNs may exert anti-inflammatory effects in ectopic endometrial stromal cells via the suppression of NF-κB activation, RANTES expression, and monocyte chemotactic activity. [ABSTRACT FROM AUTHOR]

Objective: To develop a method for ng quantitation of circulating DNA in serum and explore the value in the diagnosis of cancer., Methods: Serum DNA was extracted by commercial "genomic DNA extraction kit" and detected by fluorescent dye (SYBR green I) staining. Loss of heterozygosity (LOH) at BRCA1 (D17S579, D17S855) and p53 (TP53, D17S786) in serum DNA was analyzed by PCR-based method., Results: SYBR green I dot staining could detect DNA as low as 2 ng. Using this method, we detected serum samples from 483 patients with various types of cancer and 150 healthy individuals. The mean DNA concentration in the normal controls was 22.2 +/- 13.4 ng/ml, while that in cancer patients was 81.3 +/- 98.3 ng/ml (P < 0.001). In 33 ovarian cancer patients with increased DNA level, 27(81.8%) displayed LOH in at least one of the four loci analyzed., Conclusion: Circulating DNA in serum may become additional tumor marker for the diagnosis of cancer.

Objective: Intestinal obstruction is a frequent sequela of recurrent ovarian cancer and difficult to deal with. We analyzed a series of such patients to determine if their outcomes have changed after undergoing palliative surgery., Method: We retrospectively reviewed 67 patients undergoing surgery for intestinal obstruction due to recurrent ovarian carcinoma and 75 patients receiving non-surgical treatment from 1997 to 2002., Results: During the study period, 67 operations were performed on 67 patients. Among them, surgical procedure was completed in 58 cases. Successful palliation was achieved in 64.2% of cases in which surgical correction was possible. The median survival of the entire cohort was 7.8 months, and 12.6 months for the surgically successfully relieved patients and 3.7 months for those non-surgical patients. The rate of major surgical morbidities was 22.4%. The perioperative mortality rate was 6.0%. Successful palliation was associated with the absence of two prognostic factors: multiple obstructive sites and palpable abdominal and pelvic masses., Conclusion: Palliative surgery for bowel obstruction in recurrent ovarian cancer can be worthwhile, and properly selected patients are the key to its success.

Objective: To investigate the incidence, the diagnosis, the multimodal treatment and the relevant factors of the brain metastases in patients with epithelial ovarian carcinoma (EOC)., Method: The clinical data were analysed in 10 cases of brain metastases from 478 cases of EOC after treatment between 1996 - 2001., Results: The incidence of brain metastases in EOC was 2.1%. The most common manifestation of the brain metastases was headache, nausea and limb paralysis. The most common metastatic sites were the cupular and occipital part of the cerebra. Seven of ten patients were treated with brain radiation and systemic chemotherapy, three abandoned. The brain irradiation dosage was 30 - 38 Gy for only one focus in the brain lasting for 4 weeks and 40 - 45 Gy for two or three foci in the brain lasting for 5 weeks. The overall survival after identification of brain metastases was < 1 - 33 months, the overall median survival was 6.3 months, but for those who abandoned treatment, the median survival was 1.4 months vs 8.3 months for those who completed the courses of therapy., Conclusions: The diagnosis of brain metastasis was based on the clinical features and the imagings and the therapy was comprehensive and palliative. However, the number and size of the brain metastases and its reaction to radiation was significantly associated with the prognosis. Although the survival after the identification of brain metastases in EOC is poor, most patients can be palliated successfully by using a combination of radiation therapy and systemic chemotherapy.