BACKGROUND: It has become a hot issue to treat malignant tumors with retroviral mediated cytokines. But it remains a controversy whether retroviral mediated γ-interferon(IFN-γ) is valid in killing glioma cells and prolonging the survival of tumor carriers.OBJECTIVE: To observe the effect of retrovital mediated γ-interferon on the growth of glioma and the survival of tumor-carrying rats.DESIGN: Completely ramdomized trial based on animals.SETTING: Neurosurgery department of a hospital affiliated to a university.MATERIALS: The trial was conducted in the Neurosurgery Institute of Harbin Medical Unicersity from July 2002 to July 2004. The subjects were 60 male Wistar rats provided by the Animal Center of the First Affiliated Hospital of Harbin Medical Unicersity. They were randomly assigned into 3groups: C6 control group, C6/PA317neo control group and C6/PA317IFN-γ treatment group, 20 in each group.INTERVENTIONS: Retroviral vector containing murine IFN-γ gene was transferred into retroviral package cell PA317. A high titer PA317IFN-γ cell line was obtained after G418 resistance screening. In the right basal ganglion area 1 × 106 C6 cells was injected in each of the rats. The rats in C6groups received no more intervention. Those in C6/PA317neo control group received injection of 1 × 106 PA317IFN-γ cells in the right basal ganglion 4days after C6 injection. Those in C6/PA317IFN-γ treatment group received injection of 1 × 106 PA317IFN-γ cells in the right basal ganglion 4 days after selected from each group to be kill, and the brains were taken out to make frozen sections for SABC immunohistochemical staining. The CD4 and CD8 T was measured with imaging processing software under microscope.RESULTS: The mean survival time of rats in C6 and C6/PA317neo control groups was(27.10 ± 0.82) days and (26.60 ± 0.93) days respectively( P ＞ 0.05), while that in treatment group was(49.30 ± 4. 17) days and there were five rats outlived beyond 60 days( P ＜ 0.01 vs the two controls). The tumor volume in the two control groups was of no difference but the tumor volume in treatment was significantly smaller than that in control groups( P ＜ 0. 01 ) . The CD4 and CD8 lymphocytes infiltration in treatment group was more than that in control groups( P ＜ 0.01) and there was no difference between the two controls( P ＞ 0.05) . It was also revealed through immunohistochemical examination that in treatment group there was Brdu positive cells on the 7th day and they disappeared on the 16th day. But there was no Brdu positive cells in the control groups.CONCLUSION: Intratumor injection of PA317IFN-γ induces anti-tumor immunal reaction in rats. Retroviral mediated IFN-γ inhibits tumor growth and prolongs rat survival.

Objective:To investigate the effects of IL-12p35 small interference RNA on immune functions of Dendritic cells in rats.Methods:DCs were generated by culturing bone marrow progenitor cells of rats with GM-CSF, IL-4 and LPS in vitro. The IL-12p35 siRNA was synthesized and transfected into DCs. The expressions of CD80 and MHCⅡwere examined by flow cytometry. Reverse transcriptase PCR analysis was used to detect IL-12p35 mRNA transcription and ELISA was used to detect IL-12 and IL-10 protein levels, respectively. The antigen presenting by DCs was evaluated by mixed lymphocyte responses.Results:IL-12p35 siRNA silenced DCs expressed lower IL-12, higher IL-10,and exhibited weak activity in stimulating the proliferation of allogenic T cells, but no changes on CD80 and MHCⅡexpressions.Conclusion:IL-12p35 siRNA interference exerts no effects on maturation of DC, but negative effect on immume function of DCs.

Objective To investigate surgical indications,techniques and effects for intraeranial arachnoid cyst in children. Methods Clinical data from 82 surgical cases were analyzed retrospectively,and different methods of operation were analyzed comparatively.Four operation-methods were adopted,in which cyst removal were performed in 19,cyst removal plus cisternal opening in 23,cyst-peritoneal shunt in 28,and cyst-peritoneal drainage in 16.Results Upon following up from six months to five years after operation,the chief symptoms got improved in 89.0% of the patients,and CT or MRI scan showed that the size of cvst became smaller in 72 of the patients.Four operation methods were compared,cyst removal was not better than the other three operation methods.Conclusions The treatment of operation methods could make the svmptoms improved and the cyst thrunk of intracranial arachnoid cyst in children.The operation of cyst removal plus cisternal opening or cyst-peritoneal shunt and cyst-peritoneal drainage is preferred.

Objective To analyze the MRI features of central neurocytoma (CNC),and to improve the diagnostic accuracy of this lesion.Methods The MRI findings of 12 patients with CNC confirmed by surgery and pathology were evaluated retrospectively.All patients underwent contrast-enhanced and uncontrast-enhanced MR scan,and 3 patients also received plain CT scan.Results The lesions of 12 cases were all located in the lateral ventricles of septum pellucidum,which were close to the Monro's foramen.5 lesions located in the right lateral ventricle,5 lesions located in both lateral ventricles with 1 case reached the third ventricle,2 lesions located in the left lateral ventricle with 1 case reached the third ventricle.The mean diameter of the CNC lesions was 4.8 cm (ranged from 2.2 to 7.8 cm).11cases (92％) had vavious degrees of cystic change,8 cases (66.7％) had a spongy or soap bubble appearance and 1 case(8.3％) had completely cystic change.3 cases (25％) had a scalloping appearance on sagittal T1-weighted MRI.The solid part of the tumor was similar to the gray matter in signal intensity,with slightly high signal intensity on T2FLAIR.Among 9 cases with DWI,7 cases showed high signal intensity,1 case showed equal signal intensity,and 1 case showed slightly low signal intensity.On enhanced MRI,the solid part of tumors showed slight to medium (83％) or obvious (17％) enhancement.Conclusion CNC should be first considered when a young adult has a lesion located in the lateral ventricles of septum pellucidum,accompainied by varying degrees of cysts,showed slight to medium enhancement in the solid part of the tumor.

Objective To find out current distribution of Oncomelania snails and Schistosoma infection in snails in Zhejiang Province, so as to improve the project of schistosomiasis control. Methods Investigation spots were selected by stratified cluster sampling method, 100 villages of 34 counties were selected from 7 106 villages of 55 counties as survey spots. Synchronously systematic and environmental samplings were used for the survey. Snails were dissected to determine the infection status and spots with sham snails were set to assess the quality of the survey. Results The result showed that snails were found in 223 strips, 1 572 frames and 73 300 m 2 area in 32 villages of 21 counties. Snails were found in an area covering 72 640 m 2 in 29 villages of 18 counties in hilly region, which accounted for 99.1% of total snail habitats. The significantly larger area with snails was revealed in hilly region than that in water network region (t=3.04, P