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Daocheng Wu

Publications and source records attributed to Daocheng Wu.

6 recordsLinked to original sources
PubMed2006

High efficient degradation of dyes with lignin peroxidase coupled with glucose oxidase.

The H(2)O(2) supply strategy was one of crucial factors for high efficient degradation of pollutants with lignin peroxidase (LiP). In this paper, an attempt was made to couple a H(2)O(2) producing enzymatic reaction to the LiP catalyzed oxidation of dyes. H(2)O(2) needed was generated by glucose oxidase (GOD) and its substrate glucose. The generation rate of H(2)O(2) could be easily controlled by adjusting the pH of the degradation system and the amount of GOD added. Due to the controlled release of H(2)O(2), a sustainable constant activity of LiP was observed. The inhibition of LiP by high level H(2)O(2) supplied externally by a single addition at the beginning of the experiments could be avoided. Degradation of three dyes (xylene cyanol, fuchsine and rhodamine B) with LiP coupled with GOD indicated that the present H(2)O(2) supply strategy was very effective for improvement of the efficiency of the decolourization of dyes.

Benzenesulfonates↗
PubMed2006

Preparation and drug release characteristics of Pingyangmycin-loaded dextran cross-linked gelatin microspheres for embolization therapy.

Gelatin microspheres (GMs) containing Pingyangmycin hydrochloride were prepared for the interventional embolization by a double-phase emulsified thermal gelation method using oxidized dextran (ox-dex) as the cross-linking agent. The average diameter of the microspheres was 82 microm with 74% ranging from 50-200 microm. Drug content and the characteristics of drug release in vitro and in vivo were evaluated using UV-spectroscopy and HPLC, respectively. The prepared microspheres showed a rather high percentage of encapsulation ranging from 85 to 88% and drug content at 7.2%. The results of in vitro experiments showed that about 65.5% of the total amount of the encapsulated drug was released after 6 h at 37 degrees C. Experiments conducted through artery perfusion and artery embolization in rabbits revealed that the local drug concentration was significantly higher than the systemic blood-drug concentration, with a high level of local drug concentration maintained for more than 120 min after artery embolization with the Pingyangmycin-loaded ox-dex-GMs. The results indicated that the external carotid artery embolization with Pingyangmycin-loaded ox-dex-GMs at reduced dosages prolonged the local drug concentration at a higher level, and could achieve the purpose of a localized targeting tumor therapy. Compared with other embolization materials, ox-dex-GMs are an excellent alternative interventional embolization material for the treatment of head and neck tumors.

Animals↗
PubMed2005

Enhanced immune response to gastric cancer specific antigen Peptide by coencapsulation with CpG oligodeoxynucleotides in nanoemulsion.

CpG oligodeoxynucleotides (CpG ODN) have been shown to have potent adjuvant activity for a wide range of antigens. Of particular interest is their improved activity when closely associated with the antigen. The purpose of this study is to construct a nanovaccine coencapsulated with a gastric cancer specific antigen MG7 mimotope peptide and adjuvant CpG ODN 1645 using new nanotechnology as nanoemulsion and evaluate its immunocompetence. Nanoemulsion vaccine was prepared using magnetic ultrasound methods. BALB/c mice were immunized and the in vivo effectiveness was evaluated using tumor challenge assay. It was shown that the tumor masses formed in the mice immunized with coencapsulated nanovaccine (0.0825 g) markedly smaller (P < 0.01) than those formed in the mice immunized with nanovaccine encapsulated with antigen peptide alone (0.4465 g). A tumor inhibiting rate as high as 82.5% of the coencapsulated nanovaccine was obtained, while nanovaccine encapsulated with peptide only could not achieve the same effect (28.5%) (P < 0.01). Enzyme-linked immunospot assay (ELISPOT) showed that immunization using MG7 mimotope peptide coencapsulated with CpG ODN within the same nanoemulsion enhanced the frequency of splenocytes secreting IFN-gamma significantly (P < 0.01) when compared with immunization using MG7 peptide encapsulated in nanoemulsion alone (197spots/1 x 10(6) vs. 73 spots/1 x 10(6)). Cellular ELISA indicated that serum titer of antibody against MG7-Ag was significantly higher (P < 0.01) in mice immunized with coencapsulation form nanovaccine (0.7884) than that in the group immunized with nanovaccine encapsulated with MG7 peptide alone (0.3616). Using intracellular flow cytometric analysis, it was found that the IFN-gamma response was contributed by CD4+ T-cells. Our experiments suggest that a vaccinal approach using nano-delivery system carrying in tumoral epitope and CpG ODN as adjuvant may have important implications for cancer therapy.

Animals↗
PubMed2003

[Pingyangmycin gelatin microspheres: preparation and drug release characteristics].

Pingyangmycin gelatin microspheres(PYM-GMS) was prepared by optimal double-phase emulsified condensation polymerization for the interventional Chemoembolization with carotid artery therapy, and its release characteristics were studied in vivo and in vitro. The results of three ways of administration(vein drop, artery perfusion and artery embolization) were compared. The experiment indicates that the diameter of PYM-GMS is more appropriate for the application in external carotid artery embolization with PYM-GMS, which significantly reduces the circulating drug level and the dosage, prolongs the time period of higher drug concentration, achieves the purpose of sustained release and targeted tumor therapy.

Animals↗
PubMed2002

[Research and development on microwave sterilization].

This paper reviews recent research and development on microwave sterilization, including the experiments of sterilization effects, the influence of microwave radiating on the media parameters, the development of microwave sterilizers and the study of sterilization mechanism. Many results show that the method of microwave sterilization is more easy-to-perform, economical and reproducible than the conventional autoclaving method. It is necessary to study the sterilization conditions through the experiments for different media and bacteria. The research on sterilization mechanism, especially non-thermal sterilization mechanism is still a hotpoint.

Bacteria↗