AIM: To study the activation of cytotoxic T lymphocytes (CTLs) against gastric cancer cells induced by FasL/B7-1 (FB-11) gene-modified tumor cells, and to explore whether co-expression of FasL and B7-1 in SGC-7901 tum...AIM: To study the activation of cytotoxic T lymphocytes (CTLs) against gastric cancer cells induced by FasL/B7-1 (FB-11) gene-modified tumor cells, and to explore whether co-expression of FasL and B7-1 in SGC-7901 tumor cells could initiate synergistic antitumor effect. METHODS: FasL and B7-1 genes were transfected into human SGC-7901 gastric cancer cells with adenovirus vectors. The positive clones were selected by G418. FasL and B7-1 genes were detected by flow cytometry and RT-PCR. Abdominal infiltrating lymphocytes and sensitized spleen cells were obtained from mice that were immunized with SGC-7901/FB-11 or wild type SGC-7901 cells intraperitoneally, and cytotoxicity of these CTLs against tumor cells was determined by MTT assay. RESULTS: Flow cytometry and RT-PCR showed that FasL and B7-1 genes were highly expressed. FasL and B7-1 transfected cancer cells had a high apoptosis index. DNA laddering suggested that FasL and B7-1 genes induced gastric cancer cell apoptosis. FasL+/B7-1+SGC-7901 cells (SGC-7901/FB-11) were inoculated subcutaneously in the dorsal skin of C57BL/6 mice and then decreased their tumorigenicity greatly (z = 2.15-46.10, P＜0.01). SGC- 7901/FB-11 cell-sensitized mice obtained protective immune activity against the rechallenge of wild type SGC 7901 cells (z = 2.06-44.30, P＜0.05). The cytotoxicity of CTLs induced by SGC-7901/FB-11 cells against SGC-7901 was significantly higher than that of CTLs activated by wild-type SGC-7901 cells (84.1±2.4% vs30.5±2.3%,P＜0.05).CONCLUSION: FasL and B7-1 genes can effectively promote the activity of CTLs against gastric cancer cells. FasL/B7-1 molecules play an important role in CTL cytotoxicity.展开更多
Migration inhibitory factor-related protein 14 (MRP 14) is one of calcium-binding proteins,referred as S 100A9. The heterodimeric molecule formed by MRP 14 with its partner MRP8 (S 100A8) is the major fatty acid carri...Migration inhibitory factor-related protein 14 (MRP 14) is one of calcium-binding proteins,referred as S 100A9. The heterodimeric molecule formed by MRP 14 with its partner MRP8 (S 100A8) is the major fatty acid carrier in neutrophils.The MRP8/14 complex has been also implicated in the intracellular transport of arachidonic acid and its precursors in keratinocytes. We show here the involvement of MRP14 in human esophageal cancer. In an initial study,mRNA differential display - reverse transcription polymerase chain reaction (DD-PCR) was performed with two esophageal carcinomas,one esophageal adenocarcinoma and matched normal adjacent mucosa. DD-PCR with the arbitrary primer OPA3 showed that one cDNA band was highly expressed in normal tissues,but disappeared or substantially decreased in tumor counterparts. It was later identified to be the 3'-end of migration inhibitory factor-related protein 14 (MRP14).Northern blotting,RT-PCR and Western blotting corroborated the down-regulation of MRP14 in 58/64 squamous cell carcinomas and 2/2 adenocarcinomas as compared with adjacent normal epithelia of the esophagus. MRP14 was undetectable in 3/3 esophageal-carcinoma cell lines. Immunochemistry demonstrated that expression of MRP14 was restricted to normal esophageal epithelia. No mutation was found in the genomic DNA of the MRP14 gene by PCR and directed DNA sequencing. Our finding suggested that the reduction of MRP14 expression is a frequent event in Chinese human esophageal cancer.展开更多
The microstructural evolution of pearlite during severe cold rolling in Fe-0.8C binary alloy and Fe-1Mn-0.8C ternary alloys was investigated by using SEM, TEM and XRD etc. The results show that the deformed pearlite c...The microstructural evolution of pearlite during severe cold rolling in Fe-0.8C binary alloy and Fe-1Mn-0.8C ternary alloys was investigated by using SEM, TEM and XRD etc. The results show that the deformed pearlite consists of irregularly bent lamella, coarse lamella with shear-band and fine lamella. As the rolling reduction increases, the proportion of fine lamella increases. The strong plastic deformation, amorphization and dissolution of cementite take place during the severe cold rolling. The maximum carbon content in ferrite reaches 0.15 mass% after 90% cold rolling.展开更多
AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length huma...AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length human FasL cDNA was constructed and used to infect a human gastric cancer (SGC-7901) cell line. FasL expression was confirmed by X-gal staining, flow cytometric analysis and RT-PCR. The effect of FasL on cell proliferation was determined by clonogenic assay, cytotoxicity was detected by MTT assay, and cell viability was measured by trypan blue exclusion. The therapeutic efficiency of Ad-FasL in vivo was investigated with a xenograft tumor model in nude mice. RESULTS: SGC-7901 cells infected with Ad-FasL showed increased expression of FasL, resulting in significantly decreased cell growth and colony-forming activity when compared with control adenovirus-infected cells. The cytotoxicity of anti-Fas antibody (CH-11) in gastric cancer cells was stronger than that of ActD (91±8 vs60±5,P<0.01), and the cytotoxicity of Ad-FasL was stronger than that of CH-11 (60±5 vs50±2, P<0.05). In addition, G1-phase arrest (67.75±0.39 vs 58.03±2.16, P<0.05) and apoptosis were observed in Ad-FasL-infected SGC-7901 cells, and the growth of SGC-7901 xenografts in nude mice was retarded after intra-tumoral injection with Ad-FasL (54% vs 0%,P<0.0001). CONCLUSION: Infection of human gastric carcinoma cells with Ad-FasL induces apoptosis, indicating that this target gene might be of potential value in gene therapy for gastric cancer.展开更多
This paper focuses on the robust H-infinity reliable control for a class of nonlinear neutral delay systems with uncertainties and actuator failures. We design a state feedback controller in terms of linear matrix ine...This paper focuses on the robust H-infinity reliable control for a class of nonlinear neutral delay systems with uncertainties and actuator failures. We design a state feedback controller in terms of linear matrix inequality(LMI)such that the plant satisfies robust H-infinity performance for all admissible uncertainties, and actuator failures among a prespecified subset of actuators. An example is also given to illustrate the effectiveness of the proposed approach.展开更多
The aging precipitation behavior of beta phase in two kinds of alloys with7/3 and 9/1 ssickel4o-iron ratios during aging at 800 deg C after deformation was studied. Theresults show that there are two different kinds o...The aging precipitation behavior of beta phase in two kinds of alloys with7/3 and 9/1 ssickel4o-iron ratios during aging at 800 deg C after deformation was studied. Theresults show that there are two different kinds of aging hardness variation mechanisms (thesoftening mechanism and the hardening mechanism) deciding the hardness variations of the alloys.when Ni/Fe is smaller than8/2, there is only the softening mechanism which results from the decreasing of dislocation densityand recovery or re-crystallization. And when NI/Fe is greater than 8/2 besides the softeningmechanism there is still the hardening mechanism that is induced by the precipitation of beta phase.展开更多
基金Supported by the Medical Scientific Foundation of Jiangsu Province, No. H200147
文摘AIM: To study the activation of cytotoxic T lymphocytes (CTLs) against gastric cancer cells induced by FasL/B7-1 (FB-11) gene-modified tumor cells, and to explore whether co-expression of FasL and B7-1 in SGC-7901 tumor cells could initiate synergistic antitumor effect. METHODS: FasL and B7-1 genes were transfected into human SGC-7901 gastric cancer cells with adenovirus vectors. The positive clones were selected by G418. FasL and B7-1 genes were detected by flow cytometry and RT-PCR. Abdominal infiltrating lymphocytes and sensitized spleen cells were obtained from mice that were immunized with SGC-7901/FB-11 or wild type SGC-7901 cells intraperitoneally, and cytotoxicity of these CTLs against tumor cells was determined by MTT assay. RESULTS: Flow cytometry and RT-PCR showed that FasL and B7-1 genes were highly expressed. FasL and B7-1 transfected cancer cells had a high apoptosis index. DNA laddering suggested that FasL and B7-1 genes induced gastric cancer cell apoptosis. FasL+/B7-1+SGC-7901 cells (SGC-7901/FB-11) were inoculated subcutaneously in the dorsal skin of C57BL/6 mice and then decreased their tumorigenicity greatly (z = 2.15-46.10, P＜0.01). SGC- 7901/FB-11 cell-sensitized mice obtained protective immune activity against the rechallenge of wild type SGC 7901 cells (z = 2.06-44.30, P＜0.05). The cytotoxicity of CTLs induced by SGC-7901/FB-11 cells against SGC-7901 was significantly higher than that of CTLs activated by wild-type SGC-7901 cells (84.1±2.4% vs30.5±2.3%,P＜0.05).CONCLUSION: FasL and B7-1 genes can effectively promote the activity of CTLs against gastric cancer cells. FasL/B7-1 molecules play an important role in CTL cytotoxicity.
基金supported by State Key Basic Research programme of China(G1998051205)National Key Technologies R&D Programme of China(2002BA711A06)+2 种基金The National High Technology Research and Development Program of China(2001AA221151)National Natural Science Foundation of China(30125026)Doctoral Program Fund of China(20010023016).
文摘Migration inhibitory factor-related protein 14 (MRP 14) is one of calcium-binding proteins,referred as S 100A9. The heterodimeric molecule formed by MRP 14 with its partner MRP8 (S 100A8) is the major fatty acid carrier in neutrophils.The MRP8/14 complex has been also implicated in the intracellular transport of arachidonic acid and its precursors in keratinocytes. We show here the involvement of MRP14 in human esophageal cancer. In an initial study,mRNA differential display - reverse transcription polymerase chain reaction (DD-PCR) was performed with two esophageal carcinomas,one esophageal adenocarcinoma and matched normal adjacent mucosa. DD-PCR with the arbitrary primer OPA3 showed that one cDNA band was highly expressed in normal tissues,but disappeared or substantially decreased in tumor counterparts. It was later identified to be the 3'-end of migration inhibitory factor-related protein 14 (MRP14).Northern blotting,RT-PCR and Western blotting corroborated the down-regulation of MRP14 in 58/64 squamous cell carcinomas and 2/2 adenocarcinomas as compared with adjacent normal epithelia of the esophagus. MRP14 was undetectable in 3/3 esophageal-carcinoma cell lines. Immunochemistry demonstrated that expression of MRP14 was restricted to normal esophageal epithelia. No mutation was found in the genomic DNA of the MRP14 gene by PCR and directed DNA sequencing. Our finding suggested that the reduction of MRP14 expression is a frequent event in Chinese human esophageal cancer.
基金The financial support of the Iron and Alloy Institute of Japan is gratefully acknowledged.One of the authors(Wantang Fu)appreciates the support from the National Natural Science Foundation of China(No.50271061).
文摘The microstructural evolution of pearlite during severe cold rolling in Fe-0.8C binary alloy and Fe-1Mn-0.8C ternary alloys was investigated by using SEM, TEM and XRD etc. The results show that the deformed pearlite consists of irregularly bent lamella, coarse lamella with shear-band and fine lamella. As the rolling reduction increases, the proportion of fine lamella increases. The strong plastic deformation, amorphization and dissolution of cementite take place during the severe cold rolling. The maximum carbon content in ferrite reaches 0.15 mass% after 90% cold rolling.
基金Supported by the Medical Scientific Foundation of Jiangsu Province, No. H200147
文摘AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length human FasL cDNA was constructed and used to infect a human gastric cancer (SGC-7901) cell line. FasL expression was confirmed by X-gal staining, flow cytometric analysis and RT-PCR. The effect of FasL on cell proliferation was determined by clonogenic assay, cytotoxicity was detected by MTT assay, and cell viability was measured by trypan blue exclusion. The therapeutic efficiency of Ad-FasL in vivo was investigated with a xenograft tumor model in nude mice. RESULTS: SGC-7901 cells infected with Ad-FasL showed increased expression of FasL, resulting in significantly decreased cell growth and colony-forming activity when compared with control adenovirus-infected cells. The cytotoxicity of anti-Fas antibody (CH-11) in gastric cancer cells was stronger than that of ActD (91±8 vs60±5,P<0.01), and the cytotoxicity of Ad-FasL was stronger than that of CH-11 (60±5 vs50±2, P<0.05). In addition, G1-phase arrest (67.75±0.39 vs 58.03±2.16, P<0.05) and apoptosis were observed in Ad-FasL-infected SGC-7901 cells, and the growth of SGC-7901 xenografts in nude mice was retarded after intra-tumoral injection with Ad-FasL (54% vs 0%,P<0.0001). CONCLUSION: Infection of human gastric carcinoma cells with Ad-FasL induces apoptosis, indicating that this target gene might be of potential value in gene therapy for gastric cancer.
基金This work was supported by the National Natural Science Foundation of China (No. 60274009)the SRFDP (No. 20020145007)the Natural Science Foundation of Liaoning Province (No.20032020).
文摘This paper focuses on the robust H-infinity reliable control for a class of nonlinear neutral delay systems with uncertainties and actuator failures. We design a state feedback controller in terms of linear matrix inequality(LMI)such that the plant satisfies robust H-infinity performance for all admissible uncertainties, and actuator failures among a prespecified subset of actuators. An example is also given to illustrate the effectiveness of the proposed approach.
基金National Natural Science Foundation of China (No.59971007)
文摘The aging precipitation behavior of beta phase in two kinds of alloys with7/3 and 9/1 ssickel4o-iron ratios during aging at 800 deg C after deformation was studied. Theresults show that there are two different kinds of aging hardness variation mechanisms (thesoftening mechanism and the hardening mechanism) deciding the hardness variations of the alloys.when Ni/Fe is smaller than8/2, there is only the softening mechanism which results from the decreasing of dislocation densityand recovery or re-crystallization. And when NI/Fe is greater than 8/2 besides the softeningmechanism there is still the hardening mechanism that is induced by the precipitation of beta phase.
