Objective To establish the analysis criteria of nucleoplasmic bridges (NPB) and a dose-response curve of NPB frequencies in human peripheral blood lymphocytes irradiated by 60Co γ-rays.Methods Human peripheral blood samples were collected from three healthy males,and were irradiated with 0,1,2,3,4,5 and 6 Gy of 60Co γ-rays.A cytokinesis-block micronucleus assay was carried out to analyze NPBs and micronuclei (MN) in binucleated cells.Results NPBs in binucleated cells at each dose level of γ-ray was conformed to the Poisson distribution.The dose-response curve of the γ-ray-induced NPB frequencies in human peripheral lymphocytes followed the linear-quadratic model y =(1.39 × 10-3)x2 + (4.94 × 10-3)x (R2 =0.981,P ＜ 0.05).Conclusions The dose-response curve of NPB frequencies in human peripheral blood lymphocytes induced by 0-6 Gy 60Co γ-rays was established.

Objective:To construct GM-CSF and EB virus LMP2A fusion gene recombinant adenovirus and identificate it , using recombinant adenovirus to do immunologic study.Methods:With RT-PCR and Western blot to detect GC 2A gene expression of the recombinant adenovirus , with ELISA to analysis antibodies of vAd-GC2A stimulation in murine body , lactate dehydrogenase assay to detect the mouse cellular immunity effect , thereby the recombinant adenovirus immune effect was initially analysis.T-test method was used to do preliminary analysis and evaluation of the immune effect of recombinant adenovirus .Results:GC2A fragment amplified by PCR, the size was 1 961 bp and it was the expected.The results showed, the recombinant adenovirus vAd-GC2A proteins can be recognized by sera antibody of GM-CSF ( LMP2A); the results of ELISA showed that vAd-GC2A can stimulate the generation of antibodies.EBV-positive tumor cell killing rate (%) by CTL induced recombinant adenovirus was (66.7 ±6.9)%, at the same time the adenovirus type 5 wild strains and PBS were (24.3 ±2.5)%and(32.4 ±3.1)%only(P≤0.05).Conclusion:Fusion gene has been successfully constructed , vAd-GC2A in mice have humoral and cellular immune function.The data suggest that the vAd-GC2A should play a potent role in preventing the positive EB virus tumor.

Objective To identify the expression of a fusion gene GCA formed from GM-CSF gene and LMP2A gene of Epstein-Barr virus (EBV) in a recombinant BCG (rBCG) and to study its immunoge-nicity.Methods The rBCG was constructed to express the fusion gene GCA and the expressed products were detected by Western blot assay .ELISA was performed to measure specific antibody titers in serum sam-ples from mice immunized with rBCG .Lactate dehydrogenase assay was used to analyze the cellular immuni-ty of mice.A mouse model of EBV-positive gastric carcinoma was established to evaluate the therapeutic effects of rBCG.Results The target proteins of GM-CSF and LMP2A were successfully expressed in rBCG . The specific antibodies were detected in rBCG immunized mice as indicated by ELISA .The maximum anti-body titer reached 1 ∶27 900 [(326.5±7.8) pg/ml] as injection with rBCG 5×108/mouse.The rBCG in-duced cytotoxicity of cytotoxic lymphocytes (CTLs) to EBV-positive gastric carcinoma cells (GT39) (with a killing rate of 89.6%±6.8%) was significantly higher than that of control group (P<0.05) The sizes of tumor in PBS control group [(1964.0±548.7) mm3] and BCG group [(1268.65±72.4) mm3] were big-ger than those in rBCG group [(168.64±78.80) mm3].Conclusion The rBCG expressing GM-CSF and LMP2A fusion gene was successfully constructed .The rBCG could induce humoral and cellular immune re-sponses in mice and inhibit the growth of tumor .

Objective To study the diagnosis and treatment of retroperitoneal schwannoma.Methods Clinical data of 11 cases of primary retroperitoneal schwannomas were analyzed retrospectively from February 1990 to September 2014.There were 6 males and 5 females,with a median age of 46 years,and the median tumor size was 9.6 cm (4.5-12.3 cm).Seven cases were revealled due to physical examination,3 cases were revealled due to ipsilateral lower back pain or discomfort,and 1 case was revealled due to right lower extremity numbness.There were no clinical manifestations of hypertension or appearance shape change,and there were no abnormal findings in routine laboratory and endocrine examinations.Radiological examination showed a retroperitoneal mass.There were 3 cases in the left adrenal gland,1 case in the right adrenal gland,3 cases in the lower pole of left kidney and 4 cases in the lower pole of right kidney.Four patients were initially diagnosed as adrenal tumors,and 7 patients were diagnosed as kidney tumors.Results All the 11 cases underwent surgical resection,with 7 cases of complete resection,1 case of capsule resection,2 cases of partial resection and 1 case of biopsy.The pathology of immunohistochemical staining showed S-100 positive in 10 cases of benign retroperitoneal schwannomas.During the follow-up period for 1.5-24 years (median 14 years),no recurrence and malignance was observed.One case of malignant retroperitoneal schwannoma died of multiple metastases in 17 months after opreation.Conclusions Primary retroperitoneal schwannoma is rare and preoperative diagnosis is difficult.Clinical manifestations and radiological findings are usually nondiagnostic,and histopathology is the only way for final diagnosis.Complete surgical resection is proved to be the best choice.

Objective:To explore the feasibility of the optimized cytokinesis-block (CB) assay on radiation-induced nucleoplasmic bridge (NPB), and to provide a scientific basis for the application of NPB in biological dose estimation.Methods:Human peripheral blood in vitro was irradiated with 2 Gy 60Co γ-rays at a dose rate of 1 Gy/min (0 Gy control group). According to the culture time after irradiation, blood samples were divided into group 48, 56, 68 and 72 h. Cytochalasin-B (Cyt-B) with a concentration of 6 μg/ml was added into the samples at 28 h and harvested at 48, 56, 68 and 72 h after irradiation, respectively. On the other hand, the blood samples were treated with different concentration of Cyt-B i. e., 0.6, 1, 2, 6 and 10 μg/ml at the beginning of culture (0 h) and harvested at 68 h after irradiation. The proportion of mononucleated, binucleated and multinucleated cells, radiation-induced NPB and micronucleus (MN) frequencies were analyzed. Results:The nuclear division index (NDI) and proportion of binucleated cells at 2 Gy and 0 Gy had tendency of increasing with cell culture time. NPB frequencies (0.023 0-0.033 0/cell) and MN frequencies had no significantly difference ( P> 0.05). With the increase of Cyt-B concentration, NDI and the proportion of binucleated cells in group 2 Gy and 0 Gy also increased, but NPB frequencies (0.023 0-0.047 0/cell) had no significant difference ( P> 0.05). MN frequencies of group 10 μg/ml were significantly lower than that of group 6 μg/ml ( U=2.74, P< 0.01). Conclusions:Cell culture time and Cyt-B concentration had no significant influence on radiation-induced NPB frequencies, suggesting that NPB could be obtained by appropriately reducing cell culture time and Cyt-B could be added into blood samples at the beginning of culture. But this protocol reduced the number of cells for further analysis, and thus its feasibility for dose estimation still need to be studied.

Objective To investigate the effect of mixed application of lecture-based learning and flipped classroom and problem-based learning in microbiology teaching. Methods The five-year program students of Grade 2013 and Grade 2014 were randomly divided into two groups, and the experimental group (48 students in the teaching reform class) carried out the blended teaching, while the contrast group (48 students of parallel class) carried on the traditional teaching. After the lecture, the teaching effect of the hybrid teaching method and traditional teaching method was analyzed after the theoretical and the experi-mental operation test were adopted, and the four part questionnaire surveys including the integrated use of knowledge, active classroom atmosphere, innovation ability and teaching satisfaction were proceeded in each group. The data of each group was analyzed by t test analysis with SPSS 19.0 respectively. Results The theory test scores of experimental group was (90.16±3.14), which was higher than the control group (82.33± 4.21). The difference between them was very significant (P=0.000). Survey results showed that the integrated use of knowledge, active classroom atmosphere, innovation ability and teaching satisfaction were higher than traditional group. The difference was statistically considered significant (P<0.01). Conclusion Hybrid teaching method is very good for training and development of students' comprehensive quality and ability. It has important significance in improving the students' score.

Objective To explore the changes of human mitochondrial COXI,ND1 and ND6 genes expression induced by ionizing irradiation.Methods Changes of human COXI,ND1 and ND6 gene expression were detected by RT-PCR and Real-time PCR 8 h after the irradiation in human lymphoblastoid cell lines,which were exposed to 1-10 Gy 60Co γ-rays.And the dose-effect relationships between expression changes of the genes and the doses were analyzed.The changes of these three genes expression were also analyzed at different post-radiation time-points between 0.5 h and 72 h after irradiation of 5 Gy in order to explore the time-effect.Results The expression of three genes COXI,ND1 and ND6,showed either the dose-effect or the time-effect after irradiation.The gene expression levels of three genes up-regulated generally and the peak change time-point was 4 h after irradiation.Conclusion Ionizing radiation,msht induce the changes of mitochondrial gene expression,and the gene expression level is up-regulated.

This paper discusses the problems of optimizing teaching of medical microbiol-ogy on the aspects of optimizing teaching matters and teaching means,of integrating teaching with learning,and training teachers,etc. to improve the teaching quality in microbiology through some innovational measures.

Objective To explore if the occupational exposure to low dose thorium could induce adaptive response in peripheral lymphocytes.Methods 40 individuals.who exposed to thorium and rare earth mixed dust(exposure group) or control in Baotou Steel Plant, were selected, and chromosome aberrations were analyzed.Then the peripheral blood samples were irradiated in vitro with 2 Gy60Co γ-rays,and unstable chromosome aberration or DNA stand breakage analysis using single cell gel electrophoresis was performed. Results The dicentrics before 2 Gy exposure in exposure group was higher than that in control(P>0.05). But the dicentries after 2 Gy exposure in exposure group was lower than that in control,but not significantly (P>0.05).The tricentrics in exposure group was significantly lower than that in control(U=3.1622, 0.0ol

Objective To establish the immortalized cell lines of peripheral blood lymphocytes for old male residents in high background radiation area(HBRA)in Guangdong,China,in order to preserve the specific genomic resources of residents in HBRA for the further genetic and molecular biological study on HBRA.Methods The peripheral blood samples of 20 old male residents in HBRA were collected after informed consent.The immortalized B lymphoblastoid cell lines,2 for each resident,were established with Epstein-Barr virus.After being frozen and recovered,the cell viability,the contamination of bacterium and mycoplaama were analyzed.The stabilization of cell lines was decided by comparing the karyotypes of the peripheral blood lymphocytes and the cell lines.Results 40 cell lines for 20 residents in HBRA were successfully established.The recovery rate of cell lines after being frozen was 100%.All the cell viablity after recovery was higher than 90%.and no contamination of bacteria and mycoplasma occurred.The karyotypes of the 20th generation cell lines were not change.Conclusion The immortalized cell lines established in this study could provide biological resources for further study on genetics and molecular biology in HBRA.