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

BACKGROUND: Embryonic stem cells (ESCs), the seed cells of all mature cells in vivo, are useful tools for nerve transplantation and developmental gene function research. Notch1 signaling pathway is the key pathway to control the ordered neural development and differentiation of many kinds of neural cells, however, there is no report on the dynamic expression of Notch1 signal during the ESC differentiation to date. OBJECTIVE: To investigate the expression of Notch1 protein, transmembrane signal transduction molecule, during directional differentiation of embryonic stem cells into neural cells. DESIGN, TIME AND SETTING: Cell research was carried out between October 2003 and October 2004 at Zhongshan Ophthalmic Center, SUN Yat-sen University, Guangzhou, Guangdong Province, China. MATERIALS: BALB/C mouse embryonic stem cell line Ⅵ (passage 11)was obtained from experimental animal center of SUN Yat-sen University, provided by professor Huang Bing. ESC culture medium was high-glucose DMEM medium with 20% bovine serum and 106 IU/L mouse leukemia inhibitory factor. Induced differentiation medium was high-glucose DMEM medium with 20% fetal bovine.serum and 5×107 mol/L retinoid acid(RA). METHODS: Passage 11 ESCs were resuscitated and incubated by ESC culture medium in incubator at 37℃ with 5% CO2. Passage 11 ESCs were subcultured after 2 or 3 days and RA was added into medium to induce differentiation. Three time points for observation were established: induced for 1, 5 and 9 days. MAIN OUTCOME MEASURES: Morphological changes were observed under inverted phase contrast microscope, MAP-2 antigen expressed in differentiated cells was detected by immunofluorescence method. Immunocytochemistry, Western Blot, flow cytometry assay were used to investigate the Notch1 protein expression. RESULTS: ESCs presented clone-like growth. After induced by RA for 9 days, single neural network was achieved around most of the cell clusters. With the prolongation of induction, MAP-2 positive neural cells increased gradually. Almost all ESC clones expressed Notch1 protein strongly or positively, but Notehl protein expression decreased gradually after induced differentiation (P < 0.01). CONCLUSION: Notch1 signal shuts off progressively during induction of ESCs into neural cells, which suggests Notch1 may play an important role in the differentiation of ESCs into neural cells.

Objective To observe the influence of warm ischemia time on acquisition of rat pancreatic islets and islet function.Method Male Wistar rats were used.After heart beats stopped,the pancreases in four groups of rats were harvested,and warm ischemia time was 0,15,30 and 45 min separately.The pancrease was preserved in UW at 4℃C for 8 h,and subjected to injection of collagenase solutions.After islets were acquired,the purity,survival rate and islet activity were tested,and statistical analysis was performed.Result The number of islets obtained in 0 min group,15 min group,30 min group and 45 min group was (433 ± 41),(396 ± 38),(350 ± 31) and (66 ± 17)IEQ/one,islet viability was 94％,88％,77％ and 25％,and purity was 88％,78％,60％ and 32％,and insulin release index was 2.38 ± 0.23,2.25 ± 0.18,2.19-± 0.18 and 1.25 ± 0.12,respectively.There was no significant difference in islet number,purity,survival rate and activity 15 min group and 30 min group between 15 min group or 30 min group and 0 min group (P＞0.05).There was significant difference between 45 min group and 0 min group in islet number,purity,survival rate and activity (P＜0.05).The survival rate and purity in 45 min group were lower than the clinical standards for islet transplantation (survival rate ＞ 75％,and purity ＞ 50％).Conclusion Warm ischemia time of 15 min in non-heart-beating brain death(NHBD) rats had no effect on islet isolation and purification.Warm ischemia time within 30 min showed no significant influence on islets of NHBD rats,which can be used in islet transplantation.Warm ischemia time at 45 min showed significant influence on islets of NHBD rats,which can't be used in islet transplantation.

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

AIM: To investigate the feasibility and effect of directly differentiation of embryonic stem cells(ESC) into neural cells induced by retinoid acid(RA) without embryonic body(EB) culture period in vitro.METHODS: ESC were digested and divided into 4 groups: group A and B were undergone EB culturing.After that,cells in group A were induced by RA,cells in group B were differentiated spontaneously,cells in group C were committedly induced by RA directly without EB culturing,and cells in group D were differentiated spontaneously without EB period.Morphologic changes were observed under inverted microscope and scanning electron microscope.MAP-2 and GFAP were detected by immunocytochemistry and flow cytometry after differentiated for 9 days.RESULTS: In groups A or C,neuron-like cells increased gradually,forming neural network.At the 9th day,a large part of cells in these groups were MAP-2 positive cells,and the positive rate was higher than that in groups B or D(P0.05).CONCLUSION: ESC was directly induced into neural cells by RA without EB culture period in vitro.This modified method has the same effect as the traditional RA 4-/4+ assay and can replace the traditional method.

Objective : To analyze the survival of patients with malignant mesothelioma, so as to provide insights into the management of malignant mesothelioma. Methods : Totally 36 patients with malignant mesothelioma admitted to Cixi Third People’s Hospital from October 2012 to January 2021 were enrolled, and the demographic features, exposure to asbestos, and diagnosis and treatment were retrospectively reviewed. The survival rate and median survival time were calculated with the life-table method, and the factors affecting the survival rate of malignant mesothelioma were identified using the Kaplan-Meier estimate and log-rank test. Results : The 36 patients with malignant mesothelioma included 6 men ( 16.67% ) and 30 women ( 83.33% ), and had a median age of 61 ( interquartile range, 14 ) years. There were 30 cases with pleural malignant mesothelioma ( 83.33% ) and 6 cases with peritoneal malignant mesothelioma ( 16.67% ), 32 cases ( 88.89% ) with a history of occupational exposure to asbestos, and 26 cases ( 72.22% ) receiving palliative treatment. The 1-, 2- and 3-year cumulative survival rates were 30%, 15% and 3%, respectively, and the median survival time was 0.71 years. In addition, there were no significant differences in the survival period among patients with malignant mesothelioma in terms of gender, age, route of asbestos exposure, duration of asbestos exposure, pathogenic site and treatment regimens ( P>0.05 ). Conclusion The 36 patients with malignant mesothelioma had a median survival period of 0.71 years, and no association was found between the survival period and asbestos exposure or pathogenic site.

Objective : To examine the diagnostic and prognostic value of long non-coding RNA (lncRNA) JPX in mesothelioma, so as to provide insights into diagnosis and prognosis of mesothelioma. Methods: Patients with clinically definitive diagnosis of mesothelioma from 2015 to 2019 that were sampled from asbestos processing plants in Zhejiang Province from 2015 to 2019 were recruited in the mesothelioma group, while healthy residents without asbestos exposure or asbestos-related diseases in the same area served as controls. Participants' demographics, pathologic diagnosis and imaging features were collected, and the expression of blood lncRNA JPX was detected using lncRNA microarrays. The diagnostic value of lncRNA JPX for mesothelioma was evaluated using the receiver operating characteristic (ROC) curve, and the correlation between lncRNA JPX expression and prognosis was examined among mesothelioma patients using survival analysis. Results: There were 17 subjects in the mesothelioma group, with a mean age of (65.71±8.36) years, and 34 subjects in the controls, with a mean age of (64.24±8.70) years. LncRNA microarray detected significantly high lncRNA JPX expression in mesothelioma patients, and higher blood lncRNA JPX expression was detected in the mesothelioma group than in the control group [median (interquartile range), 1.10 (1.31) vs. 0.89 (0.54); t'=-2.300, P=0.034]. The area under the ROC curve was 0.673 (95%CI: 0.507-0.839, P=0.046), and if the cutoff was 1.759, the sensitivity and specificity were 35.3% and 100.0%, respectively. Survival analysis showed no significant difference in the survival rate of mesothelioma patients between the high lncRNA JPX expression group and the low expression group (χ2=0.212, P=0.645). Conclusions LncRNA JPX overexpression is detected in the blood of patients with mesothelioma, and lncRNA JPX expression presents a diagnostic value for mesothelioma; however, it shows little prognostic value for mesothelioma.

Graphene oxide is a novel two-dimensional carbon nanomaterial, but it has potential risks for the health of occupationally exposed workers. This article briefly reviews the research progress on the cytotoxic mechanism of graphene oxide and its derivatives in terms of oxidative stress, physical damage and dysfunction of enzyme activity. This review also discusses effective measures for the mitigation of cytotoxicity in order to provide helpful evidence for occupational health risk and biological safety assessment of graphene nanomaterials in China.

Graphene oxide is a novel two-dimensional carbon nanomaterial, but it has potential risks for the health of occupationally exposed workers. This article briefly reviews the research progress on the cytotoxic mechanism of graphene oxide and its derivatives in terms of oxidative stress, physical damage and dysfunction of enzyme activity. This review also discusses effective measures for the mitigation of cytotoxicity in order to provide helpful evidence for occupational health risk and biological safety assessment of graphene nanomaterials in China.