Evaluation of performance and application of three nucleic acid extraction methods for quantification of plasma Epstein-Barr virus DNA / 中华检验医学杂志

Objective To evaluate and compare the analytical performances and application values of three nucleic acid extraction methods for quantification of plasma Epstein-Barr Virus ( EBV ) DNA. Methods It used silica membrane spin column , boiling and automated magnetic bead method to extract viral nucleic acid in parallel , and combined real-time fluorescence quantitative PCR assays for quantitative EBV-DNA quantification.The performances of three methods were determined and compared by using the third-party reference materials , and the clinical values were analyzed by pairing detecting 100 NPC patients and 100 healthy subjects in pair .Results The accuracy and imprecision of three methods were all in line with requirements , and the results of clinical samples were linearly correlated . But actually the reproducibility and intermediate imprecision of the magnetic bead method were smaller and stable than those of the spin column method and the boiling method ( all <3％);the limit of detection for the magnetic bead method was 3.334 ×101 IU/ml, better than that of spin column method (4.159 ×101 IU/ml) and boiling method (8.511 ×101 IU/ml);the linear range of the magnetic bead method was 5.4 ×101 -5.4 ×105 IU/ml, slightly wider than that of the boiling method (5.4 ×102 -5.4 ×105 IU/ml); the ability of anti -Hb interference ability of magnetic bead method is better than that of boiling method ;and the positive rate and the mean viral load of the NPC samples measured with the magnetic bead method were significantly higher (95％, 8.342 ×103 IU/ml) than those measured with the spin column method (84％, 4.707 ×103 IU/ml) and the boiling method (78％, 2.571 ×103 IU/ml) ( P all<0.05).Conclusion The automated magnetic bead nucleic acid extraction method offered better analytical performance and higher clinical value for EBV DNA quantification in plasma .

Influence of electroporation on immunogenicity of the DNA vaccine pVAX-tG250FcGB / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the influence of electroporation on the immunogenicity of the DNA vaccine pVAX- tG250FcGB.</p><p><b>METHODS</b>The DNA vaccine pVAX-tG250FcGB was constructed by inserting the coding gene of tG250 fusion genes into the expression vector pVAX. The DNA vaccine was delivered in BALB/c mouse by electroporation or intramuscular injection, and the induced antigen specific immune responses were compared.</p><p><b>RESULTS</b>The vaccine delivered by electroporation and intramuscular injection both induced immune responses in BALB/c mouse, but electroporation produced an obviously stronger effect than intramuscular injection.</p><p><b>CONCLUSION</b>Electroporation-mediated DNA vaccine delivery can produce strong immune response in mice and is an effective means for studying the immunogenic effect of DNA vaccine pVAX-tG250FcGB.</p>

Identification of novel metastasis associated genes MAG-1 and MAG-2 / 中国肺癌杂志

<p><b>BACKGROUND</b>To isolate and identify the genes related to cancer metastasis by comparison of two cell strains with different metastasis potentials subcloned from human lung giant cell carcinoma cell line.</p><p><b>METHODS</b>Suppression subtractive hybridization (SSH) was used to compare the levels of gene expression between the two cell strains and SSH library was constructed. After screening the library by gene chip, the expressed sequence tags (ESTs) with different expressing level were sequenced and blasted with GenBank.</p><p><b>RESULTS</b>Seventy-nine genes were obtained that were expressed much higher in PLA-801D than in PLA-801C, including two full-length cDNA. GenBank Accession numbers of the two cDNA, named MAG-1 and MAG-2, were BC006236 and BC002420, the 8.5 kb MAG-1 gene was composed of four exons and located on the chromosome of 4q21. The MAG-2 gene, which was made up by 9 exons, had a length of 5.2 kb and its location was 2q35. Both sequences had open reading frames (ORF) and promoters before the theoretical transcription start points. Using special software, the secondary structure of theoretical products of the two cDNAs was prognosticated, α-helix was the main proportion, but β-pleated sheet and random coil were also included.</p><p><b>CONCLUSIONS</b>The expression of MAG-1 and MAG-2 has significant differences in these two cell strains, so they might impact tumor metastasis in some ways that are still uncharted.</p>

ON THE BIOCHEMICAL ACTION AND RADIORESISTANT ACTIVITY OF POLYSACCHARIDES EXTRACTED FROM RADIX BUPLEURI AND POLYPORUS UMBELLATE(PERS.) / 解放军医学杂志

Polysaccharides extracted from radix of Chinese DC and dried Polyporus umbellate (pers) as well as a well known mitogen,phytohemagglutinin(PHA),were studied.It has been revealed that both the poly-saccharides as well as PHA stimulate the rate of DNA synthesis characterized by their increasing the incorporation of 3H-TdR and accelerating the release of thymus cells. These effects disappeared after adrenalectomy.Corticosterone concentration was found to be increased in the plasma after the administration of the polysaccharides These phenomena suggested that the adrenal cortex was the mediator of their actions. When they were administered to animals before an irradiation of 800 rad, the survival rate was increased by 30-70% over that of the controls. The mechanism of the effects was discussed.

Combined application of MS-275 and curcumin in inhibiting cell survival signaling pathways and inducing apoptosis of prostate cancer cells / 解放军医学杂志

Objective Curcumin and MS-275,an inhibitor of histone deacetylase (HDAC),are promising anti-tumor agents. The aim of present study was to investigate the mechanisms of apoptosis induced by combined use of MS-275 in low dosage and curcumin in prostate cancer cell line DU145. Methods MTT assay was used to evaluate the lethal effect on DU145 cells by solitary use of MS-275 and or combined with curcumin. The changes in cell life cycle was detected by flow cytometry. The expressions of the survival signaling pathways were determined by Western blotting. Results Solitary application of MS-275 or curcumin may inhibit the growth of DU145 cells in a time and dose-dependent manner. The combination of MS-275 (1?mol/L) and curcumin (20?mol/L) exhibited obvious cytotoxic effect on cell viability,which was only 45.9% 48h after the combined treatment. Cell cycle assay showed that the combination of MS-275 and curcumin resulted in obvious appearance of sub-G1 phase in DU145 cells,implying that the cell apoptosis had been induced. The results of Western blotting showed that after treatment of MS-275 or curcumin singly,the phosphorylation level of Akt and ERK kinase declined slightly,however,when MS-275 and curcumin were used together,there appeared a prominent inhibitory effect on Akt and ERK kinase,indicated by a sharp decline of their phosphorylation level,and at the same time,the level of cleaved PARP,a hallmark of apoptosis,was increased in DU145 cells. Conclusion Combined use of MS-275 and curcumin may exert a synergistic cytotoxic effect on the viability of DU145 cells,and exhibit an inhibitory activity on Akt and ERK kinases to induce apoptosis.