ABSTRACT
Objective To explore prostaglandin E 2 (PGE 2) production pathway in Toxoplasma gondii-infected macrophage RAW264.7 cell line.Methods Cells were incubated with Toxoplasma gondii tachyzoites and lipopolysaccharides (LPS). Prostaglandin synthesis and arachidonic acid in supernants were detected with ELISA and gas chromatogram. Expression of cyclooxygenase-1/cyclooxygenase-2 (COX-1/COX-2) mRNA and protein following stimulation with LPS or infection of Toxoplasma gondii were evaluated with RT-PCR and Western blot in presence or absence of peculiar antagonists of PGE 2 production. Results PGE 2 synthesis of macrophages began at 4-8 h after invasion with Toxoplasma gondii and saturated at 12-16 h. Expression of COX-2 mRNA peaked at 4-8 h, and diminished in presence of both indomethacin and nimesulide, COX-2 protein expression was not affected by them. Expression of COX-1 mRNA and protein were constant and not affected by either indomethacin or nimesulide. Conclusion Toxoplasma gondii may induce macrophages prostaglandin E 2 synthesis via cyclooxygenase-2 pathway.
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Objective To investigate the relationships between the expression of VEGF,its receptor KDR/flk-1,cNOS mRNA and angiogenesis,cell proliferation,metastasis in human hepatocellular carcinoma(HCC). Methods Immunohistochemical analysis using antibodies against VEGF and its kinase insert domain receptor (KDR) was carried out.cNOS mRNA expression in HCC,liver cirrhosis and normal liver tissue was observed by in situ hybridization.CD34 immunostaining was used to measure the microvascular density(MVD)and proliferative index was evaluated by Ki-67 immunostaining. Results The expressions of VEGF and KDR of HCC were significantly related to MVD,proliferation and metastasis of HCC(P
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Objective To study the effect of pinealctomy and melatonin on the cell cycle distribution during T cell development in thymus. Methods SD rats were divided into 5 groups:normal controls,sham-operated controls,pinealectomy,pinealectomy+melatonin injection 7.5 mg/kg; and pinealectomy+melatonin injection 15 mg/kg.The animals were sacrificed at 4 or 8 weeks after operation.cycilnA +and cyclinE +T cells in thymus were dyed with immunocytochemical ABC methods, measured by computer image analysis.Cell cycle analysis was performed by flow cytometry.The expression of cyclin-dependent kinase inhibitor 1? was tested by RT-PCR method. Results The effect of pinealectomy on the expression of cyclinE was stronger than that of cycilnA. Pinealectomy promotes the synthesis of cyclinE in thymus.The percentage of G-0/G-1 phase cells was decreased and G-2/M phase cells was increased.These would be convalescente by supplement with melatonin,but the reaction to melatonin was differencet in thymus cortex and in medulla.Melatonin enhanced the expression of cyclin-dependent kinase inhibitor 1? in thymus.Conclusion Pinealectomy influences notably the T cells development in thymus.Rejuvenation of degenerative thymus could be observed by melatonin administration.