Objective To compare the levels of four factors between gastric mucosa of Han and Tibetan patients with chronic gastritis residing in districts at the same altitude in Qinghai Province.Methods Levels of malonic aldehyde ( MDA) , superoxide dismutase (SOD) , nitric oxide ( NO) and xanthine oxidase (XOD) in gastric mucosa of Han and Tibetan patients with chronic gastritis resident in same altitude districts were examined, and a comparative study was performed.Results Levels of MDA and SOD were significantly higher in gastric mucosa of Han patients (2 2699 ± 1.58906 nmol/mgprot and 134.6313 ±48.35329 U/mgport, respectively) than those of the Tibetan (1.7095 ± 1.19474 nmol/mgprot and 109.5056 ± 28.26794 U/mgport, respectively) (P <0.05) , which indicated there were differences in metabolism of oxygen free radicals and antioxi-dant free radicals between 2 ethnics.However, there were no differences in NO and XOD levels between two ethnical groups, which suggested no ethnical difference in metabolism of the two factors.Conclusion There is ethnical difference in MDA and SOD metabolism in gastric mucosa of Han and Tibetan patients with chronic gastritis from same altitude district, which is presumably due to the different tolerance to the hypoxia at high altitude.

Objective To construct lentivirus containing CXCR4 gene and transfect MCF-7 cells , and obtain CXCR4 high-expressing MCF-7 cells. Methods CXCR4 gene was amplified by RT-PCR to construct CXCR4/pSin-EF2, which was transfected into HEK293T cells with psPAX2 and pMD2G vector for lentivirus packing. Packaged lentivirus was used to transfect human breast cancer cells MCF-7, with empty lentivirus as control. CXCR4 mRNA and protein expression levels were detected by RT-PCR and Western blot before and after transfection. And flow cytometry was used to detecte cell surface CXCR4 expression. Results The recombinant plasmid CXCR4/pSin-EF2 was constructed successfully,identified by double digestion and sequencing, and transfected into HEK293T cells to obtain high-titer lentivirus. RT-PCR and Western blot confirmed that the expression of CXCR4 in MCF-7 cells increased significantly after CXCR4 lentivirus transfection. Flow cytometry results showed that the CXCR4 positive rate increased from 26.78% to 99.29%, while there is no significant difference in CXCR4 expression between vector-transfected MCF-7 cells and non-transfected MCF-7 cells. Conclusion CXCR4 lentivirus and the breast cancer cell line with high and stable expression of CXCR4 (MCF-7CXCR4) were successfully constructed.

Objective To establish a breeding method ofMyodes rufocanus in the laboratory,collect their growth and reproduction data,and provide a basis for carrying out the experimental animalization.Methods Wild Myodes rufocanus caught in the Moranbong woodland were brought back to the laboratory.They were bred artificially in a large hard wall rodent negative pressure isolator.Their growth and reproduction data were recorded for evaluating the results of breeding.Results The Myodes rufocanus were successfully bred in the laboratory.The pregnancy rate was 54.55%.The average pregnancy length was 20.4 days(8 to 22 days).During one breeding period,they gave birth 2.9 times on average.The maximum number of births was 7 times,far more than the number tested under field conditions.The average litter size was 4.3±1.22.The highest litter number of a single nest was 8.The weaning rate of pups was 94.8%.The growth and development of pups were good.Conclusions The breeding method for Myodes rufocanus is established.The growth and reproduction data are tested too.The results of our study laid a foundation for the experimental animalization of Myodes rufocanus.

Objective To analyze characteristics of Nef-specific T lymphocyte responses in Chinese HIV-1 recombinant subtype B/C infectors. Methods 19 HIV-1 recombinant subtype B/C infectors infected within 1 year, 40 chronic infectors infected for more than 3 years were enrolled in this cohort study. Elispot assay was used to observe HIV-1 specific T lymphocyte responses in HIV-1 recombinant subtype B/C infectors. Results Nef-specific T lymphocyte responses of interferon-gamma secretion were identified in 15 Chinese HIV-1 recombinant subtype B/C infectors infected within 1 year. The specific T lymphocytes were mainly targeted at four peptides which span from Nef 83 to 135: EVA7081.1, EVAT081.5, EVA7081.6 and EVAT081.48. Responses were identified in 29(75. 2%) infectors with more than 3 years of infection and the specific T lymphocytes were mainly targeted at three peptides which span from Nef 63 to 101 : EVA7081.43, EVA7081.44, EVAT081.45, EVA7081.47, EVA7081.48 and EVA7081.49. The average magnitude of response in infectors with less than 1 year of infection was 284. 13 SFC/106 PBMC. The average magnitude of response in infectors with more than 3 years of infection was 152. 44 SFC/106 PBMC. There was a significant difference between the two groups (U = 91. 000, P = 0. 002). Conclusions HIV-1recombinant subtype B/C infectors at different stages of diseases (less than 1 year and more thank 3 years) can recognize central region of Nef. The magnitude of Nef-specific IFN-γ secretion T lymphocyte responses in this cohort gradually decrease with disease progression.

Objective To analyze character of Nef-specific T lymphocyte responses in Chinese HIV-1 recombinant subtype C/B' and subtype B' infectors and to identify the common immunodominant re-gions recognized by these infectors. Methods Fifty-nine HIV-1 recombinant subtype C/B' infectors and 27 subtype B' infectors were tested by IFN-γ enzyme linked immunospot (ELISPOT) assay using HIV-1 C/B' Nef overlapping peptides. Results Nef-specific T-cell responses of IFN-γ secretion were identified in 44 (74.58%) out of 59 HIV-1 recombinant subtype C/B' infectors. Ten peptides, EVA7081.1,5, 6, 7,43, 44, 45, 47, 48, 49 were mainly recognized. Amino acid position was from Nef63 to 115 and 117 to 139. Twenty of 27 (74.07%) HIV-1 subtype B' infectors recognized peptides. EVA7081.1,2, 43 and 49 were mainly recognized. Amino acid position was from Nef 63 to 77 and 87 to 119. There was no correlation be-tween the Nef-specific IFN-production of HIV-1-specific T cells responses and viral load or CD4 T cell count in both subtype infectors. Conclusion The immunodominant regions, from Nef63 to 77 and 87 to 115 were recognized by both Chinese HIV-1 recombinant subtype C/B' infectors and subtype B' infectors. These re-gions could be used in design of vaccine.

Objective To evaluate the detection of serum pepsinogen (PG) in screening of gastric cancer. Methods (1) To calculate the detection rate of gastric cancer in PG Positive patients from northeastern, noah-western and northern China. (2) To determine the PG positive rate in patients with chronic superficial and atrophic gastritis. (3) To calculate the detection rate of gastric cancer, H. pylori infection and esophageal cancer in PG positive patients from gastric cancer high risk areas. Results (1) The detection rate of gastric cancer in PC, positive patients from Changchun (northeastern China), Xihing (northwestern China) and Beijing ( northern China) was 22. 58%, 25. 2% and 0, respectively. The sensitivity of PG to seeen gastric cancer in Changchun and Xihing was 50. 9% and 35.6%, and the specificity was 82. 56% and 85.69%, respectively. (2) Only 25% of patients with chronic atrophic gastritis were PG positive. (3) The serum PG level was measured in 2346 cases from gastric cancer high risk areas, and PG positive rate was 27.02% (634/2346), in which 496 patients (76. 65%, 496/634) received endoscopy, and gastric cancer was detected in 10 (2. 02%, 10/496), including 9 cases of early gastric caner. The prevalence of gastric cancer was 0. 43% in common population and 1.58% in PG positive population. The infection rate of H. pylori was 70. 73% in 2346 subjects and 2 cases of esophageal cancer, including 1 case of early cancer was diagnosed. Conclusion Serum PG level cannot be used as a marker for gastric cancer or atrophic gastritis, while it may be of value for gastric cancer screening in high risk areas.

BACKGROUND:Many scholars at home and abroad have already attempted to apply the technique of the internal fixation pedicle screw placement to cure children’s spinal injuries in recent years, because the children’s thoracic pedicle is more smal , anatomical structure variation is big and adjacent relationship is complicated, so the application of adult’s pedicle screw technology simply to children who was in a continuous growth and development can increase operation risk greatly. Above this, improving the accuracy of nailing and reducing error rate become keys for further development of cervical pedicle fixation. OBJECTIVE:To provide an individualized and accurate positioning method for screw placement in thoracic pedicle of children by computer aided design and rapid prototyping technology. METHODS:After computed tomography scan of four cases of child specimens, the original data were made for three-dimensional reconstruction by the software, then the specimens were randomly divided into two groups:one group used the traditional pedicle internal fixation method, and the other group, first created the individual navigation template using the principle of reverse engineering and rapid prototyping technology. The lumbar pedicle screws were put into the samples by the individual navigation template. The position of the pedicle screws was evaluated according to the computer tomography scan. RESULTS AND CONCLUSION:The accurate rate of screw placement of the traditional pedicle internal fixation method was 58%;and the accurate rate of screw placement of the individual digital navigation template method was 81%. The success rate was better than the traditional surgery group. Furthermore, chi square test showed that there was a significant difference between two groups (P<0.05). These findings suggested that there has a high accuracy of the screw placement in thoracic pedicle of children assisted by the individual navigation template, ful y reflects the principle of individualization of screw placement, and provides a new feasible method for accurate screw placement in thoracic pedicle of children.

OBJECTIVETo construct a soluble prokaryotic expression vector of the CXCR7-specific antagonist SDF-1/54R and evaluate its activity.

METHODSSDF-1/54r gene amplified by PCR was inserted into the soluble expression vector pET-41a+ engineered with GST fusion tag, and the recombinant vector was transformed into E. coli strain BL21 (DE3). After IPTG induction of E. coli, the expressed recombinant protein was purified with GST affinity chromatography purification system and confirmed by SDS-PAGE and Western blotting assay. The target protein SDF-1/54R was obtained after digestion of the purified product with enterokinase. Breast cancer MCF-7 cells with high expression of CXCR7 was treated with SDF-1/54R and the cell proliferation and metastasis was evaluated with MTT and chemotaxis assays.

RESULTSThe target protein SDF-1/54R obtained showed an obvious inhibitory effect on the proliferation and metastasis of MCF-7 cells as confirmed by MTT and chemotaxis assays.

CONCLUSIONSDF-1/54R is a good antagonist of CXCR7 and shows a potential value as an effective anti-cancer agent.

Blotting, Western ; Chemokine CXCL12 ; metabolism ; Chromatography, Affinity ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli ; Genetic Vectors ; Humans ; Polymerase Chain Reaction ; Receptors, CXCR ; antagonists & inhibitors ; Recombinant Proteins ; biosynthesis

Objective Grey red-backed voles (Myodes rufocanus) are agile, fierce and hard to catch, thus, it is difficult to judge their gender by external appearance, especially for the juvenile voles. Therefore, it may cause difficulties to their allocation and later breeding in laboratories. The aim of this paper is to establish a rapid, simple and accurate method for gender identification of grey red-backed voles. Methods Fresh hair follicles were taken from 6 adult male voles, 3 adult females and 14 4-week-old juvenile voles, 5 male and 5 female 9-week-old Wistar rats, and 5 male and 3 female 6-week-old BALB/c mice. The genomic DNA was extracted using Chelex-100 resin and the zinc-finger Y/X gene (ZFY/ZFX) and the gene of sex-determining region of the Y (SRY) chromosome were amplified by PCR, and a double PCR amplification method was established. Results The ZFY/ZFX gene and SRY gene were simultaneously amplified from the male voles, while only the ZFY/ZFX gene was amplified from the females. The gender of all 23 voles, 10 Wistar rats and 8 BALB/c mice were correctly identified with this method, and the PCR results were consistent with the phenotypic and autopsy results. Conclusions Using fresh hair follicles as experimental materials for gender identification of grey redbacked voles can alleviate shock and damage to the animals. The established double PCR amplification method is accurate, simple, rapid, and deserves to be used for gender identification of grey red-backed voles.

Objective To explore the predictive value of CT image texture analysis for early enlargement of hypertensive intracerebral hemorrhage.Methods One hundred and eight patients with hypertensive intracerebral hemorrhage were divided into enlarged hematoma group (positive group)and non-enlarged hematoma group (negative group),according to whether the volume of hematoma on 24 h follow up CT scan was more than 30% or 6 mL of the baseline CT.Phillis Radiomics Tool V93 software was used to segment the hematoma on CT plain scan images of two groups,four features of first-order and three of gray-level co-occurrence matrix (GLCM),thirteen of gray-level size zone matricx (GLSZM)and eleven of gray-level run-length matricx (GLRLM)were obtained.The differences of thirty-one texture features between the two groups were compared.The ROC curves of the features with statistical differences were analyzed.The independent predictors of early enlargement of intracerebral hemorrhage were screened by Logistic multivariate regression model.Results Among the one hundred and eight patients,twenty-eight were positive group and eighty were negative group.Skewness and long run low gray-level emphasis (LRLGE)in positive group were significantly higher than those in negative group (P＜0.05).There was no significant difference in the remaining twenty-nine features between the two groups (P＞0.05).ROC curve analysis showed that the AUC of Skewness,LRLGE and their combined diagnosis were 0.634,0.814 and 0.828,respectively.The independent variables were screened by stepwise regression analysis.The LRLGE (OR＝1.238,95%CI＝1.009－1.51 9,P＜0.05)was selected as the regression model, suggesting that LRLGE was an independent predictor of the early enlargement of intracerebral hemorrhage.Conclusion Texture analysis of CT images is helpful to predict the early enlargement of hypertensive intracerebral hemorrhage,and LRLGE based on GLRLM algorithm can be used as an independent predictor.