During radiation for head and neck cancers,part of parotids are contained in planning target volume(PTV),which lead to parotids receiving radiation as the same as PTV.Radiation for head and neck cancers will influence the parotids.In the period of radiation,many factors will influence parotids,such as age,primary parotid volume,V10-40,weight and mean radiation dose et al.These factors will result in that the parotid volume reduces nearly 50％ and moves toward the middle line of the body.As a result,the real dose of the parotid receiving is higher than prescription dose.The excretion function of the parotid will be severely damaged after radiation,which will lead to xerostomia and influence the quality of patients life.

Proton magnetic resonance spectroscopy (HMRS) is the only way to study noninvasively the metabolic and biochemical signature of the human tissues and organs.It can also quantify the metabolites within the volume of interest.The metabolic information about the lesions provided by the HMRS can greatly improve the diagnostic,grading accuracy,treatment planning such as target delineation and posttreatment follow-up of the glioma.

The application of 18 F-FDG PET-CT in the diagnosis and treatment of nasopharyngeal carcinoma includes early diagnosis,clinical staging,contouring target volume,predicting the sensitivity of tumors to radiotherapy and effect evaluation,and monitoring the residual and recurrence.However,18 F-FDG uptake of tumor cells is under the influence of various factors,so false positive and false negative are unavoidable.Therefore it is need to develop more specific tracer agent in order to improve the accuracy of diagnosis and treatment,as well as to carry out multicenter clinical trial to identify the correlation of standardized uptake value (SUV)and radiation target volume.

Radiotherapy is one of the most important treatments for glioma; however its therapeutic effect is unsatisfying. Timing, accurate target outlining, a total dose higher than 60Gy, conformal modulating radiotherapy and combined chemotherapy and targeted therapy are important factors in improving the outcome of radiotherapy.

BACKGROUND: The precartilaginous stern cells are limited regarding in vitro proliferative capacity, but the immortalized cell lines can provide a large number of stable immortalized cells, and simian virus 40 large T antigen gene (SV40Tag) is one of gene fragments which are commonly used and effective in vitro immortalized ceils. OBJECTIVE: To construct human immortalized precartilaginous stem cells (IPSCs) using human precartilaginous stem calls induced by SV40LTAg gane. METHODS: The human immortalized precartilaginous stem calls were isolated from aborted fetus and purified with enzyme digestion and immunomagnetic beads screening method. By using liposome-mediated gene transfection technology, plasmid pCMVSV40T/PUR containing SV40Tag was transfected in primary embryonic precartilaginous stem cells, while non-transfected cells sewed as negative controls. Positive clones were cultured to observe the cell morphology and the passage recovery, to calculate cell survival rata and population doubling time, to drew call growth curve. Immunofluorescence cytochemistry was used to detect the expression of IPSCs fibroblast growth factor receptor 3, the expressions of SV40Tag and fibroblast growth factor receptor 3 in the human precartilaginous stem cells were determined by RT-PCR. RESULTS AND CONCLUSION: Morphology of human IPSCs seemed coincidence with primary human precartilaginous stem cells. The survival rate of human IPSCs was not influenced by subculture, freezing and recovery, but the survival rate was descended in the human precartilaginous stem cells at the 6~(th) and 10~(th) passages (P < 0.01). Compared with cells at the 6~(th) and 10~(th) passages, the proliferation of human IPSCs was greater, with short population doubling time and high growth rate (P < 0.01). The immunofluorescence showed that fibroblast growth factor receptor 3 was positive in human IPSCs at the second passage, and the RT-PCR results of fibroblast growth factor receptor 3 revealed a specific amplification band at 400 bp,.while that of SV40Tag revealed at 560 bp. No band was seen in the primary cells. It is indicated that SV40Tag human IPSCs can be constructed successfully using immunomagnatic bead screening technology and liposome transfection technique.

Immortalized human precartilaginous stem cells (IPSCs) were established to provide stable cell resource for the study of the molecular mechanism of gene targeting on the differentiation of PSCs. Plasmid pCMVSV40T/PUR containing simian virus 40 large T antigen gene (SV40Tag) was transfected into human PSCs by using lipofectin transfection. Colonies were isolated by puromycin selection and expanded by multiple passages. Immunohistochemistry, RT-PCR and Southern blotting were used to identify the transfected cells and to detect the expression and integration of SV40Tag in expanded cell lines. The positive colonies were isolated and subcultured, designated immortalized precartilaginous stem cells (IPSCs), which were confirmed as fibroblast growth factor receptor-3 (FGFR-3) positive cells by immunohistochemistry and RT-PCR. SV40Tag cDNA was found in cultured IPSCs of passage 8 by Southern blotting, and the expressions of SV40Tag mRNA and protein were confirmed by RT-PCR. These findings suggested that IPSCs strain with SV40Tag was constructed successfully.
Cartilage/*cytology ; Cell Proliferation ; Cell Transformation, Viral ; Cells, Cultured ; Fetus ; Simian virus 40/*genetics ; Stem Cells/*cytology ; Transfection

Objective To study the biological effects of pulsed electromagnetic fields (PEMFs) on the pro-liferation of immunomagnetically separated human precartilaginous stem cells (PSCs) in vitro. Methods The cells from an aborted fetus's metaphysis were digested using collagenase. The PSCs were isolated by magnetic cell sorting (MACS), then subcultured and amplified. Flow cytometry, immunohistochemistry, immunofluorescence and RT-PCR analysis were performed to identify the purified PSCs. The PSCs were stimulated by PEMFs at 50 Hz frequency and 1 mT intensity. Cell proliferation was measured at different time points using methyl thiazolyl tetrazolium ( MTT), and the cell growth curve was plotted. Flow cytometry was applied to measure the cell cycle and apoptosis. Results The PSCs were successfully cultured. There was fibroblast growth factor receptor-3 (FGFR-3) on their sur-face. Cell proliferation was promoted after 4 and 6 days of PEMF stimulation. The percentage of cells at the S phase was higher than in a control group. Early, late and total rates of apoptosis in the experimental group decreased signifi-cantly. Conclusion PEMFs can enhance the proliferation and inhibit the apoptosis of human PSCs, and it is possi-ble to cultivate the high density human PSCs in vitro.

BACKGROUND:Several studies have shown the improvement of heart function through the introduction of mesenchymal stem cells(MSCs)from bone marrow,which may be attributed to secretion of various cytokines that accelerate endogenous reparative process,but not regeneration of cardiomyocytes.OBJECTIVE:To observe the anti-apoptotic effects of MSCs on adriamycin(ADR)-injured cardiomyocytes apoptosis in vitro through paracrine pathway.METHODS:In vitro cultured neonatal rat cardiomyocytes(3×10~8/L)were incubated into a 6-well plate,3 mL/well.72 hours later,these cells were assigned into 3 groups.The primary cultured neonatal rat cardiomyocytes in the ADR-injured and coculture groups were exposed to 1 mg/L ADR for 4 hours to establish experimental models of toxic cardiomyocytes.The normal control group was left intact.In the coculture group,rat bone marrow MSCs(BMSCs)at passage 3 were regulated to 3×10~8/L,3 mL/well was added into Millicell device for 24 hours.Following model induction,the Millicell device was inseted into above-mentioned 6-well plate to establish coculture system.The levels of cytokines were measured in the conditioned medium from three cardiomyocytes groups.Effects of BMSCs on Caspase-9 and Caspase-3 activities,apoptosis and Bcl-2 and Bax protein expression in ADR-injured cardiomyocytes were measured.RESULTS AND CONCLUSION:Compared with the normal control group.the level of cytokine including insulin-like growth factor (IGF-1)and hepatocyte growth factor(HGF)was significantly higher in the medium from ADR-injured group.the activity of caspase-9,caspase-3 and the apoptosis rate increased significantly,the expression of Bax protein was higher and Bcf-2 Protein was lower in ADR-injured group(P ＜ 0.05).Compared with the ADR-injured group,the level of IGF-1 and HGF in co-cultured group increased significantly,the apoptosis rate,Caspase-3 and Caspase-9 activities decreased significantly,the expression of Bax protein was lower while Bcl-2 Protein was higher than ADR-injured group(P ＜ 0.05).Results indicated that BMSCs show increased cytokine secretion and significant anti-apoptotic effects on ADR-injured cardiomyocytes through paracrine pathway.

Objective To evaluate the prognostic value of the expression of epidermal growth factor receptor (EGFR) and nm23 in patients with nasopharyngeal carcinoma (NPC). Methods From 2003 to 2006, 127 NPC patients who had undergone biopsy before radiotherapy were reviewed retrospectively. All patients received intensity-modulated radiotherapy using 6 MV X-rays combined with platinum-based chemotherapy. Immunohistochemistry SP method was adopted to detect the expression of EGFR and nm23 in NPC biopsy specimens . The relationship between the expression of EGFR and nm23 and survival was analyzed. Results The positive rate of EGFR and nm23 were 80.3% and 47. 2% respectively. The nm23expression was correlated with distant metastasis (χ2=7.03, P = 0. 008 ). The 5-year estimated local control, over-all survival (OS) and disease-free survival (DFS) were 58.3% ,53.5% and 46. 5%. Patients with negative expression of EGFR had a significantly better 5-year OS, DFS (χ2=8.23, P=0.004;χ2=5.25,P=0.022) than those with positive expression. Patients with positive expression of nm23 had a significantly higher 5-year OS (χ2=15.68, P = 0. 000) and DFS (χ2=14. 85, P = 0. 000) than those with negative expression. The clinical stage, EGFR and nm23 expression were independent prognostic factors shown by Cox proportional hazard model (χ2=23.03, 18.33, 39.92, P= 0.000, 0.000, 0.000).Conclusions The EFGR and nm23 expression were correlated with the prognosis in NPC patients.

To explore the feasibility and accuracy for evaluating mitral regurgitation (MR) severity with MR jet volume (MRvol) by means of general imaging three-dimensional quantification (GI3DQ). Methods: A total of 93 MR patients were divided into 2 groups: Central MR group, n=41 and Eccentric MR group, n=52. According to real-time three-dimensional echocardiography (RT3DE) examined planimetry of effective regurgitation orifice area (EROA), the patients were graded into mild MR, moderate MR and severe MR. MRvol was directly measured by GI3DQ. Results: In Central MR group, ROC analysis showed that as GI3DQ measured MRvol>16.2 ml, AUC=0.93, P<0.0001, the sensitivity and specificity for distinguishing mild MR and moderate MR were 96.0% and 70.0%respectively; as MRvol>44.5 ml, AUC=0.96, P<0.0001, the sensitivity and specificity for distinguishing moderate MR and severe MR were 97.6% and 91.7% respectively. In Eccentric MR group, as MRvol>14.2 ml, AUC=0.77, P=0.0243, the sensitivity and specificity for differentiating mild MR and moderate MR were 91.8% and 62.5% respectively; as MRvol>40.5 ml, AUC=0.83, P<0.0001, the sensitivity and specificity for differentiating moderate MR and severe MR were 82.3% and 77.9% respectively. Conclusion: Taking RT3DE examined EROA as reference, GI3DQ directly measured MRvol could more accurately assess MR severity especially in patients with central MR, it may distinguish moderate MR and severe MR with the higher sensitivity and specificity.