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Bing Xu

Publications and source records attributed to Bing Xu.

96 records · Page 6Linked to original sources
PubMed2002

Effects and mechanism of hyperbaric oxygen on prostaglandins in alveolar bone and gingival of experimental periodontitis in animal.

OBJECTIVE: To study the effects and the therapeutic mechanism of hyperbaric oxygen (HBO) on prostaglandin E(2) (PGE(2)) in alveolar bone and gingiva of experimental periodontitis in animal. METHODS: Experimental periodontitis was produced by silk thread sutures combined with high content sugar diet. For HBO therapy, they were exposed to a pressure of 0.25 MPa (2.5ATA), breathing pure oxygen one session a day for 60 min. The treatment course was 2 weeks. The value of PGE(2) in gingiva and alveolar bone was analyzed by enzyme immunoassay (EIA). RESULTS: The value of PGE(2) in gingiva of control group was 3.21 ng/g, and that of PGE(2) in alveolar bone was 3.22 ng/g. The contents of PGE(2) in gingiva (13.96 ng/g) and alveolar bone (13.32 ng/g) of periodontitis group increased markedly than control group (P < 0.01). The contents of PGE(2) in gingiva (5.21 ng/g) of HBO group were 62.7% which was lower than that of periodontitis group, and the value of PGE(2) in alveolar bone (4.05 ng/g) were 69.6% lower than that of periodontitis group. The difference of PGE(2) in gingiva or alveolar bone was significant for the HBO group and periodontitis group (P < 0.01). CONCLUSIONS: The contents of PGE(2) in alveolar bone and gingiva increased markedly when experimental periodontitis has formed. The value of PGE(2) in alveolar bone and gingiva reduce markedly after HBO exposure, and the decreased rate of PGE(2) in alveolar bone is more evident than that of PGE(2) in gingiva after HBO therapy.

Alveolar Process↗
PubMed2001

Antioxidant Activity of Anthocyanin Extract from Purple Black Rice.

Antioxidant activity was studied for anthocyanins extracted from purple black rice (PBR) by a 3% aqueous trifluoroacetic acid solution (TFA), as well as for anthocyanins extracted from blueberry (Bluetta, high bush type). Capillary zone electrophoresis revealed that the PBR extract contained almost exclusively a single anthocyanin, which was identified as cyanidin 3-O-beta-D-glucoside (Cy 3-Glc) after purification by polyvinylpyrrolidone column chromatography. In contrast, 11 anthocyanins were identified in the blueberry extract. PBR extract showed slightly weaker superoxide scavenging and crocin bleaching activities than blueberry extract did. Both PBR and blueberry extracts, however, showed 10 to 25 times stronger activity than the same concentration of Trolox used as a reference antioxidant. It was further noted that the purified Cy 3-Glc from PBR extract retained approximately 74% of the antioxidant activity (both crocin bleaching and superoxide scavenging) observed in the original TFA extract. The hydroxyl radical scavenging activity of both extracts was several times weaker than that of the same concentration of Trolox, although the PBR extract showed approximately two times stronger activity than blueberry extract did. The hydroxyl radical scavenging activity of the purified Cy 3-Glc from PBR, however, decreased to approximately 20% of that of the original PBR extract. These results indicate that the anthocyanin Cy 3-Glc contributes to the antioxidant activity of PBR through its strong superoxide radical but not hydroxyl radical scavenging activity.

Journal Article↗
PubMed2000

[Constructing a Competitor of BCR-ABL cDNA by PCR Site-Directed Mutagenesis]

A competitive mimic of the cDNA of the BCR-ABL fusion gene was constructed, and its feasibility was testified by capillary electropheresis (CE). The 4 bp-shorter mimic was obtained by PCR amplification using a newly synthesized downstream primer analogous to the former one. Mimics of both types of BCR-ABL cDNA were achieved and the validity was verified with restriction endonuclease. And the products of the coamplification PCR could be easily separated by capillary electrophorisis. The mimic can be used to quantitative detection of BCR-ABL gene through competitive RT-PCR in chronic myeloid leukemia.

Journal Article↗
PubMedDate not supplied

99mTc-labeled cyclic RGDfK dimer: initial evaluation for SPECT imaging of glioma integrin alphavbeta3 expression.

This report describes the evaluation of biodistribution properties of three radiotracers, [(99m)Tc(SQ168)(EDDA)], [(99m)Tc(SQ168)(tricine)(PDA)], and [(99m)Tc(SQ168)(tricine)(TPPTS)] (SQ168 = [2-[[[5-[carboonyl]-2-pyridinyl]hydrazono]methyl]benzenesulfonic acid]-Glu(cyclo{Lys-Arg-Gly-Asp-d-Phe})-cyclo{Lys-Arg-Gly-Asp-d-Phe}; EDDA = ethylenediamine-N,N'-diacetic acid; PDA = 2,5-pyridinedicarboxylic acid; TPPTS = trisodium triphenylphosphine-3,3',3' '-trisulfonate), and their potential to image the glioma integrin alpha(v)beta(3) expression in BALB/c nude mice bearing the U87MG human glioma xenografts. It was found that all three radiotracers were able to localize in glioma tumors with a relatively high tumor uptake and long tumor retention time by binding to the integrin alpha(v)beta(3) expressed on both tumor cells and endothelial cells of tumor neovasculature. It seems that the coligand has minimal effect on integrin alpha(v)beta(3) targeting capability of the (99m)Tc-labeled RGDfK dimer, but it has a significant impact on their biodistribution properties. For example, the complex [(99m)Tc(SQ168)(tricine)(TPPTS)] has the lowest liver uptake and the highest metabolic stability in normal BALB/c nude mice. Results from SPECT imaging studies show that the glioma tumors can be clearly visualized with all three radiotracers at 4 h postinjection. Among the three radiotracers evaluated in this study, [(99m)Tc(SQ168)(tricine)(TPPTS)] has the best imaging quality and is a promising candidate for more preclinical evaluations in the future.

Animals↗
PubMedDate not supplied

Cribriform-morular variant of papillary thyroid carcinoma. Report of a case showing morules with peculiar nuclear clearing.

BACKGROUND: There have been only 4 reported cases of cribriform-morular variant of papillary thyroid carcinoma (CMVPTC) with cytologic findings from fine needle aspiration. In these reports, the cytologic findings do not fully reflect the histologic characteristics of this entity. We report a case of CMVPTC in which a cribriform pattern without colloid and epithelial morules with peculiar nuclear clearing (PNC) were present in smears, thus fulfilling the criteria for a cytologic diagnosis of CMVPTC. Protein truncation tests for APC molecule abnormality indicated the presence of germline mutation in the patient's APC gene. CASE: A 30-year-old woman had multiple thyroid tumors. Aspiration cytology revealed a large number of round to spindle-shaped atypical-cells showing sheet-like, cribriform, follicular, whorl-like and solid, 3-dimensional arrangements. The cribriform and follicular arrangements did not contain colloid in the lumen. The powdery chromatin pattern characteristic of papillary carcinoma was not observed, but there were scattered intranuclear cytoplasmic pseudoinclusions and grooved nuclei. The nuclei of the atypical cells presenting in the whorl formations showed enlargement, thickened nuclear membranes and entirely clear contents, consistent with PNC. Hyalinelike necrotic cells were also observed in the cell clusters or in the background. Histologic and immunohistochemical findings were typical of CMVPTC. CONCLUSION: The cribriform pattern without colloid, fascicular or whorl formation of spindle cells, and morules with PNC are identifiable on cytologic smears and are sufficiently distinctive to allow a cytologic diagnosis of CMVPTC.

Adenoma↗