Synergistic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin and N-nitrosodiethylamine on cell malignant transformation / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>The present paper aims to investigate the effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and N-nitrosodiethylamine (DEN) on tumorigenesis and its potential mechanism.</p><p><b>METHODS</b>The potentials of TCDD and DEN in separation or in combination to induce malignant transformation were tested in Balb/c 3T3 cells by using a cell transformation assay method. The possible mechanism of observed effects was studied further by adding α-naphthoflavone (α-NF), a competitive binding agent of TCDD, to the Aryl hydrocarbon receptor (AhR) pathway. The mRNA expressions of Cyp1a1 and Cyp2a5 gene in Balb/c 3T3 cells treated by DEN and TCDD in separation or in combination with or without presence of α-NF were measured with fluorescence quantification RT-PCR technique.</p><p><b>RESULTS</b>The cell transformation frequency (TF) was significantly higher in case of induction with TCDD in combination with DEN, as compared to that with either TCDD or DEN alone. These effects were not inhibited via α-NF. The mRNA expression levels of both Cyp1a1 and Cyp2a5 were enhanced by TCDD treatment alone, but this inducible effect was blocked in cells treated by TCDD and DEN in combination.</p><p><b>CONCLUSION</b>TCDD and DEN had a significant synergistic effect on tumorigenesis when they were used in combination. AhR pathway may not be the key mechanism of this synergistic effect. Thus, it is necessary to further test the potential mechanism involved in cancer development.</p>

Improve on serological diagnosis method of nasopharyngeal carcinoma / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To improve the existing serological early diagnosis method of nasopharyngeal carcinoma by improve the detection sensitivity.</p><p><b>METHODS</b>The samples of 294 serum specimen from the prevention and treatment of nasopharyngeal cancer model base, involving 106 serum specimen from the patients suffering from nasopharyngeal cancer and 188 from the healthy testers. IgA/VCA antibody and IgA/EA antibody of the serums are tested by Streptavidin-biotin-antibody immunoenzymatic test and normal traditional enzyme methods, SPSS statistical software is used to analyse the test results with chi2 test and t test.</p><p><b>RESULTS</b>Referring to 106 patients, the sera antibody positive rate tested by Streptavidin-biotin-antibody immunoenzymatic test method is obviously higher than that tested by traditional method; and the t test result of the GMT has significant difference in the two method.</p><p><b>CONCLUSION</b>The modified method can improve the sensitivity of serology testing, ensure the specificity of test results, at the same time, improve the detection rate of nasopharyngeal carcinoma, so it can be applied to the early screen work of nasopharyngeal carcinoma.</p>

Primary research of anti-influenza virus activity of "Benovoair Concentrate" / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>Anti-influenza virus activity of "Benovoair Concentrate".</p><p><b>METHODS</b>The different dilution of samples were mixed with the same quantity of 100 TCID50 virus at 37 degrees C for 30 minutes. Add suitable quantity mixture in wells containing cells. Every 3 wells were the same mode. Viruses control, cells control and samples control of different dilution were performed and set in the CO2 incubator at 37 degrees C. CPE was observed every day. When CPE appears in viruses control as "++++", stopped testing and performed the hemagglutination titration.</p><p><b>RESULTS</b>"Benovoair Concentrate" with dilution of 1:60, 1:120, 1:240 and 1:480 have 100% anti-influenza A and anti-influenza B activities. "Benovoair Concentrate" with dilution of 1:960 and 1:1920 have 25%-50% anti-influenza A and anti-influenza B activities.</p><p><b>CONCLUSION</b>The test was the proof of anti-influenza virus activities which provided for the development of "Benovoair Concentrate".</p>

Immune responses induced by recombinant adenovirus Ad5F35-LMP2 in rhesus monkeys / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To observe the specific cellular and humoral immune responses after immunization with recombinant adenovirus Ad5F35-LMP2 in rhesus monkeys.</p><p><b>METHODS</b>Sixteen rhesuses were immunized with Ad5F35-LMP2 through intra-muscular injection in three groups: high dosage group (1.5 x 10(10) TCID(50)/rhesus), medium dosage group (1.5 x 10(9)TCID(50)/rhesus), low dosage group (1.5 x 10(8)TCID50/rhesus) and the last group was control (PBS 4 ml/rhesus). They were totally immunized three times at intervals of one month. The EBV-LMP2 specific cellular immune responses were tested during the 0, 4, 8, 12 weeks by Elispot after immunization respectively. And the titers of anti-LMP2 antibody were tested by EIA at the same time.</p><p><b>RESULTS</b>EBV-LMP2 specific cellular and humoral immune responses which were induced by recombinant adenovirus Ad5F35-LMP2 can be found in all the three dosage groups. The potency of immune responses was related with the dosage of immunization. Higher dosage elicited more potent immune response.</p><p><b>CONCLUSION</b>The recombinant adenovirus Ad5F35-LMP2 could elicit LMP2 specific cellular and humoral immune responses in rhesus.</p>

Immune responses in rhesus induced by recombinant adenovirus Ad-LMP2 / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To observe the LMP2 specific cellular and humoral immune responses after immunization with recombinant adenovirus Ad-LMP2 in rhesus.</p><p><b>METHODS</b>The rhesuses were immunized with Ad-LMP2 through intra muscular injection in three groups, high dosage (4.5 x 10(11) VP/kg), medium dosage (1.5 x 10(11) VP/kg) and low dosage (0.5 x 10(11) VP/kg) groups. They were totally immunized six times at intervals of 5 days. The specific cellular immune responses were tested during the 7th week by ELISPOT after immunization. And the titers of anti-LMP2 antibody were tested by EIA throughout the period of immunization.</p><p><b>RESULTS</b>LMP2 induced specific cellular and humoral immune responses in all three dosage group. The potency of immune responses was related with the dosage of immunization. Higher dosage elicited more potent immune response. Both the neutralizing antibody to adenovirus and anti-LMP2 antibody could be detected from 2 weeks after immunization. They would reach the peak during 3-4 weeks after immunization, then declined during the 7th week after immunization.</p><p><b>CONCLUSION</b>The recombinant adenovirus LMP2 could induce specific cellular and humoral responses in rhesus after immunization.</p>

Immune response induced by HIV DNA vaccine combined with recombinant adeno-associated virus / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>HIV-1 DNA vaccine and recombinant adeno-associated virus (rAAV) expressing gagV3 gene of HIV-1 subtype B were constructed and BALB/c mice were immunized by vaccination regimen consisting of consecutive priming with DNA vaccine and boosting with rAAV vaccine; the CTL and antibody response were detected and compared with those induced by DNA vaccine or rAAV vaccine separately.</p><p><b>METHODS</b>HIV-1 subtype B gagV3 gene was inserted into the polyclonal site of plasmid pCI-neo, DNA vaccine pCI-gagV3 was thereby constructed; pCI-gagV3 was transfected into p815 cells, G-418-resistant cells were obtained through screening transfected cells with G418, the expression of HIV-1 antigen in G-418-resistant cells was detected by EIA; BALB/c mice were immunized with pCI-gagV3 and the immune response was tested; BALB/c mouse immunized with pCI-gagV3 and combined with rAAV expressing the same gagV3 genes were tested for antibody level in sera by EIA method and cytotoxicity response by LDH method.</p><p><b>RESULTS</b>pCI-gagV3 could express HIV-1 gene in p815 cells; pCI-gagV3 could induce HIV-1 specific humoral and cell-mediated immune response in BALB/c mice. The HIV-1 specific antibody level was 1/20; when the ratio of effector cells: target cells was 50:1, the average specific cytotoxicity was 41.7%; there was no evident increase in the antibody level induced by pCI-gagV3 combined with rAAV, but there was increase in CTL response, the average specific cytotoxicity was 61.3% when effector cells: target cells ratio was 50:1.</p><p><b>CONCLUSION</b>HIV-1 specific cytotoxicity in BALB/c mice can be increased by immunization of BALB/c mice with DNA vaccine combined with rAAV vaccine.</p>