Objective: To explore effect of TfR on immune function after ionizing by investigating changes in TfR expression on splenic lymphocytes of mice after whole body irradiation (WBI) with different dose X-rays. Methods: Direct immunoflurescence antibodies and flow cytometry were used to examine the changes of TfR expression. Results: The cell number of TfR positive expression in spleens increased significantly at 24 hours and 72 hours after WBI with 75 mGy X-rays but the cell number of TfR positive expression in spleens decreased significantly at 24 hours after WBI with 1～6 Gy X-rays. The activity of IL-2, meanwhile, demonstrated a parallel change. Conclusion: These results suggest that the TfR enhances immune function in low dose ionizing radiation but suppresses immune function in high dose. The change of TfR expression may be due to the change of IL-2 activity caused by ionizing radiation.

Objective To study the inhibitory effects of gene combined radiotherapy on mice transplanted with B16 melanoma.Methods Alkaline lysis assay was used to extract and purify the plasmid.Plasmid DNA was injected into tumor by microinjection assay.Mice were inoculated with 5?10~5 of B16 melanoma in right hind legs and the therapy was performed when the diameter of tumor reached at 0.30.5 cm.pNE-mIL-12 and pcDNA-B7-1 plasmids were injected locally three times following with irradiation three times.The tumor growth rate of mice was observed.Results The anti-tumor effect of pNE-mIL-12 combined with pcDNA-B7-1 plasmid following with 2 Gy X-ray irradiation was much better than other groups.It showed that the tumor growth rate was slowed,the survival days of mice were delayed significantly(P

Objective To construct the expression vectors of pSilencer3.1-hif-1? and identify the inhibition of hif-1? in Hela299 cells after transfection with the combinative plasmids.Methods The interfering sequences of hif-1? were designed according to the sequence of hif-1? of GenBank.Three recombinant plasmids of pSilencer3.1-hif-1? were constructed by DNA ligase.Trizol reagent was used to extract the whole RNA of cells and RT-PCR assay was applied to detect the expression of hif-1? mRNA.Lysis assay was used to extract the protein from cells and Western blotting was adopted to observe the expression of HIF-1? protein.Results The vectors were identified to be right after sequencing.The mRNA level was decreased 24 h after transfection with three vectors of pSilencer-hif-1?,and the ratios of hif-1? /GAPDH in control,group transfecting with pSilencer-sihif-1?-1,group transfecting with pSilencer-sihif-1?-2,group transfecting with pSilencer-sihif-1?-3 were 0.55,0.13,0.33,and 0.08,respectively(P

Objective:To find small molecular leads for inhibition on early stage of HIV infection by identification and characterization of the HIV-1 gp41 C-helix mimotopes.Methods:For identification of the gp41 C-helix mimotopes,C7C phage display peptide library was biopanning by using a synthetic peptide N36 which was derived from the gp41 N-helix as target.After three rounds of screening,positive phage clones were identified by ELISA and sequenced.Results:16 of 26 phage clones were identified to bind with peptide N36,and 10 of them were sequenced.Every clone of ten clones contains at least two hydrophobic residues,which may dock into the hydrophobic pocket in the gp41 N-helix domain.9 of the 10 clones have a conservative sequence WW,which may mimic the W628 and W631 in C-helix to interact with the hydrophobic residues in the gp41 pocket.One clone expressing the conservative sequence named clone No.8(CYWWHRLHC) was selected for characterization.The binding between the clone No.8 and N36 was blocked by free peptide N36.And the binding between clone No.8 and peptide N36 was inhibited by peptide C34(IC 50=12.5 ?g/ml).Conclusion:The short circular peptides displayed on phages containing WW residues may mimic the conformational epitope of the HIV-1 gp41 C-helix to interact with the N-helix.This information may be useful for design of HIV-1 fusion inhibitors.

Objective: In the present study we observed the general pattern of the adaptive response of thymocyte apoptosis and cell cycle progression induced by low dose radiation (LDR). Methods: Kunming male mice were irradiated with the inductive dose (D1, 75 mGy) and the challenging dose (D2, 1.5 Gy). The intervals between D1 and D2 were 3, 6, 12, 24 and 60 hours. The changes of thymocyte apoptotic bodies (TAB) and cell cycle progression were measured with flow cytometry with the thymocytes cultured for 4, 20 and 44 hours, respectively, 18 hours after irradiation with D2. Results: When the intervals between D1 and D2 were 3, 6 and 12 hours, the percentages of TAB in the D1 + D2 groups in the thymocytes cultured for 4 and 20 hours were significantly lower than those in the D2 groups (P<0.05) and the percentages of G0/G1 and G2 + M phase cells decreased in varying degrees, while the percentages of S phase cells increased significantly (P<0.05 or P<0.01). Conclusion: The results mentioned above indicate that when the mice were irradiated with 75 mGy (D1, 12.5 mGy/min) 3～12 hours before 1.5 Gy (D2, 0.285 Gy/min) exposure, the adaptive response of apoptosis and cell cycle progression may be induced with the thymocytes cultured for 4 and 20 hours after whole-body irradiation with D2.

Objective:To study effects of large dose thymopeptides on T cell subpopulations of patients with malignant tumor under radiotherapy.Methods:Fifty one patients with malignant tumor under radiotherapy were divided into 2 groups with 100 mg and 200 mg thymopeptides respectively.The patients we re given thymopeptides,100 mg/d or 200 mg/d,iv, for 10 days.The positive percent ages of CD4,CD8,CD25 and CD56 in T cells of peripheral blood before and after thymopeptide treatment were determined by flow cytometry.Results:The positive percentages of CD4 and CD25 in T cells of peripheral bl ood after 100 mg/d thymopeptide treatment were significantly higher than those befor e thymopeptide treatment (P<0.05),while those of CD4，CD8，CD25 and CD56 in T cells of peripheral blood after 200 mg/d thymopeptide treatment all increased significantly (P<0.05 or P<0.01). Conclusion:These results suggest that large dose of thymopeptides can increase i mmune function of patients with malignant tumor under radiotherapy,and the curat ive effect of 200 mg/d thymopeptides is better.

AIM To modify and improve a screening assay so that it becomes more convenient, economic and adaptable in China for high throughput screening of HIV fusion inhibitors targeting gp41. METHODS The original screening method reported by Jiang et al (J Virol. Methods 1999;80:85 96) was modified by: ① using a conformation specific monoclonal antibody to replace a polyclonal antibody for coating plates; ②simplifying the procedures; ③using parts of the reagents produced in China. RESULTS The modified screening assay is simpler, more convenient, and more economic than the original assay, but its sensitivity is comparable to and specificity is a little better than the original method. CONCLUSIONS The modified screening assay is more convenient and economic and can be used in China for high throughput screening of HIV fusion inhibitors from complex sample, such as phage display peptide libraries, microorganism fermentation liquids, herbs and other natural products.

Malignant tumor has become the largest disease threatening human health.The global incidence of cancer is in-creasing year by year.At present,the poor quality of life and drug resistance of patients with advanced and recurrent cancer are be-coming increasingly obvious.Reducing the invasion and metastasis of tumor,improving the survival and prognosis of tumor patients,are urgent problems to be solved in tumor treatment.Agrin is a membrane protein associated with synaptic formation,and recent studies have shown that Agrin plays an important role in the occurrence and development of tumors.Agrin is expressed in malignant tumors and immune cells,playing an important regulatory role in tumor angiogenesis,cell proliferation and migration,chemotherapy resist-ance,and neutrophil infiltration.This article summarizes and analyzes the current research status of Agrin,especially its related role and mechanism in the occurrence and development of malignant tumors.

Objective To explore the mechanism by which Sestrin2(SESN2)regulates autophagy activity of chondrocytes by mediating mammalian rapamycin target protein complex 1(mTORC1)signaling pathway.Methods The normal chondrocytes were treated with interleukin-1 β(IL-1β)to establish an osteoarthritis(OA)chondrocyte model,which was divided into the control group and the IL-1 β-treated group.Real-time quantitative PCR(qPCR)and Western blot were used to detect the expression levels of matrix metalloproteinase 13(MMP13),type Ⅱ collagen(COL2A1)and SESN2 in the two groups.The cell models of the chondrocyte overexpression SESN2 group and knockdown SESN2 group were obtained via cell transfection technology,and the expression levels of SESN2 in each group were detected by qPCR while those of SESN2,MMP13,COL2A1,mTORC1 pathway-related proteins and autophagy-related proteins in each group were detected by Western blot.The effects of SESN2 on cell proliferation and migration were detected by CCK-8 and cell scratch assay.Results(1)The expression level of MMP13 in the IL-1 β-treated group was significantly up-regulated,while the expression levels of COL2A1 and SESN2 were significantly decreased.(2)Compared with the control group,the expressions of p-mTORC1,ribosomal protein S6 kinase 1(S6K1),and MMP13 protein in OA chondrocytes in the overexpression group were significantly down-regulated,while the expressions of adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)and chondroprotective gene COL2A1 were significantly increased,and the expression level of Beclin-1 and the ratio of microtubule associated protein 1 light chain 3-Ⅱ(LC3-Ⅱ)/(LC3-Ⅰ)were increased.Meanwhile,overexpression of SESN2 could up-regulate the proliferation and migration of chondrocytes,but the results were opposite after knockdown of SESN2.Conclusion SESN2 can enhance autophagy,proliferation and migration of chondrocytes by inhibiting mTORC1 pathway,which has provided data for revealing the pathogenesis of OA and exploring new therapeutic methods.

Objective To investigate the incidence of osteonecrosis of the femoral head (ONFH) in divers of Dalian.Methods From January 2010 to December 2010,all registered 855 divers in Dalian were enrolled in this study.All divers underwent a unified medical examination and a questionnaire including height,weight,blood pressure and hip inspection.Radiological examination (anteroposterior and frog position)was used for all divers.Suspicious persons with hip pain but normal X-ray performance were confirmed by MRI.Results Sixty-eight divers were confirmed as ONFH,and the incidence of ONFH in divers of Dalian was 7.95％.According to the Ficat classification,12 patients (12 hips) were in Phase 1,40 patients (47 hips)in phase Ⅱ,3 patients (3 hips) in phase Ⅲ,13 patients (15 hips) in phase Ⅳ.The mean age of divers was 32.6+5.5 years (range,18-55 years).The onset ages of most patients ranged from 30 years to 50 years,accounted for 83.82％ (57/68).Among all patients,primary school education accounted for 10.58％ (38/359),junior high school education 6.28％ (28/446),high school education 4.26％ (2/47),university education 0 (0/3); seniority less than 5 years accounted for 4.55％ (20/440),6-10 years 9.69％ (28/289),11-15 years 13.04％ (12/92),16-20 years 21.05％ (4/19),more than 20 years 26.67％ (4/15); self-employed accounted for 11.88％ (19/160),private enterprise 8.41％ (38/452),and national enterprise 4.53％ (11/243).Conclusion The incidence of ONFH is high in divers of Dalian,which is different in terms of age,seniority,level of education,enterprise nature.