AIM: To study interactions between hepatitis B virus (HBV) and interferon-a in liver- derived cells. METHODS. mRNAs were separately isolated from an HBV-transfected cell line (HepG2 2.2.15) and its parental cell line ...AIM: To study interactions between hepatitis B virus (HBV) and interferon-a in liver- derived cells. METHODS. mRNAs were separately isolated from an HBV-transfected cell line (HepG2 2.2.15) and its parental cell line (HePG2) pre- and post-interferon-a (IFN-a) treatment at 6, 24 and 48 h, followed by hybridization with a cDNA microarray filter dotted with 14 000 human genes. After hybridization and scanning of the arrays, the data were analyzed using ArrayGauge software. The microarray data were further verified by Northern blot analysis. RESULTS: Compared to HepG2 cells, 14 genes with known functions were down-regulated 3 to 12- magnitudes, while 7 genes were up-regulated 3-13 magnitudes in HepG2 2.2.15 cells prior to IFN-a treatment. After interferon-a treatment, the expression of four genes (vascular endothelial growth factor, tyrosine phosphate 1E, serine protein with IGF-binding motif and one gene of clathrin light chain) in HepG2 2.2.15 were up-regulated, while one gene encoding a GTP-binding protein, two genes of interferon-induced kinases and two proto-oncogenes were further down- regulated. Interestingly, under IFN-a treatment, a number of differentially regulated genes were new ESTs or genes with unknown functions. CONCLUSION: The up-regulated genes in HepG2 2.2.15 cell line suggested that under IFN-a treatment, these repressed cellular genes in HBV infected hepatooltes could be partially restored, while the down- regulated genes were most likely the cellular genes which could not be restored under interferon treatment. These down-regulated genes identified by microarray analysis could serve as new targets for anti-HBV drug development or for novel therapies.展开更多
Let (M^3+k, T) be an involution on a closed manifold such that its fixed point set is L^1 (p).In this paper, we determine the existence of (M^3+k, T) and give the equivariant bordism classification of such involutions.
This paper deals with two parabolic initial-boundary value problems in multidimensional domain. The first problem describes the situation where the spherical medium is static and the nonlinear reaction takes place onl...This paper deals with two parabolic initial-boundary value problems in multidimensional domain. The first problem describes the situation where the spherical medium is static and the nonlinear reaction takes place only at a single point. We show that under some conditions, the solution blows up in finite time and the blow-up set is the whole spherical medium. When the spherical medium is allowed to move in a special space, we investigate another parabolic initial-boundary value problem. It is proved that the blow-up can be avoided if the acceleration of the motion satisfies certain conditions.展开更多
OBUECTIVE To screen differentially expressed genes in the development of human glioma and establish a primary molecular classification of glioma based on gene expression using cDNA microarrays.METHODS Brain specimens ...OBUECTIVE To screen differentially expressed genes in the development of human glioma and establish a primary molecular classification of glioma based on gene expression using cDNA microarrays.METHODS Brain specimens were obtained from 18 patients with glioma, 10 males and 8 females, ages 14-62 with an average age of 44.4. The total RNAs of these glioma specimens and two specimens of donated brain of normal adults were extracted. BioStarH140S microarrays (including 8,347 old genes and 5,592 novel genes) were adopted and hybridized with probes which were prepared from the total RNAs. Differentially expressed genes between normal tissues and glioma tissues were assayed after scanning cDNA microarrays with ScanArray4000. Northern hybridization and in situ hybridization (ISH) were used to identify functions of novel genes. Those differentially expressed genes were studied with a Hierarchical method and molecular classification of glioma was preliminary carried out.RESULTS Among the 13,939 target genes, there were 1,200 (8.61%) differentially expressed genes, of which 395 (2.83%) were novel genes. A total of 348 genes were up-regulated and 852 genes were down-regulated in the gliomas. The results of bioinformatical analysis, Northern hybridization and ISH revealed that those novel genes were highly associated with gliomas. There were multiple genes, such as the MAP gene,cytoskeleton & matrix motility genes, etc, which were of relevance to classification by the Hierarchical method. Molecular classification of glioma using a Hierarchical cluster was in accordance with pathology and suggested a molecular process of tumorigenesis and development.CONCLUSION Multiple genes play important roles in development of glioma, cDNA microarray technology is a powerful technique in screening for differentially expressed genes between two different kinds of tissues. Further analysis of gene expression and novel genes would be helpful to understand the molecular mechanism of glioma development.展开更多
基金Supported by the Chinese State Basic Science Foundation,No.1999054105 and Med-X Foundation of Fudan University
文摘AIM: To study interactions between hepatitis B virus (HBV) and interferon-a in liver- derived cells. METHODS. mRNAs were separately isolated from an HBV-transfected cell line (HepG2 2.2.15) and its parental cell line (HePG2) pre- and post-interferon-a (IFN-a) treatment at 6, 24 and 48 h, followed by hybridization with a cDNA microarray filter dotted with 14 000 human genes. After hybridization and scanning of the arrays, the data were analyzed using ArrayGauge software. The microarray data were further verified by Northern blot analysis. RESULTS: Compared to HepG2 cells, 14 genes with known functions were down-regulated 3 to 12- magnitudes, while 7 genes were up-regulated 3-13 magnitudes in HepG2 2.2.15 cells prior to IFN-a treatment. After interferon-a treatment, the expression of four genes (vascular endothelial growth factor, tyrosine phosphate 1E, serine protein with IGF-binding motif and one gene of clathrin light chain) in HepG2 2.2.15 were up-regulated, while one gene encoding a GTP-binding protein, two genes of interferon-induced kinases and two proto-oncogenes were further down- regulated. Interestingly, under IFN-a treatment, a number of differentially regulated genes were new ESTs or genes with unknown functions. CONCLUSION: The up-regulated genes in HepG2 2.2.15 cell line suggested that under IFN-a treatment, these repressed cellular genes in HBV infected hepatooltes could be partially restored, while the down- regulated genes were most likely the cellular genes which could not be restored under interferon treatment. These down-regulated genes identified by microarray analysis could serve as new targets for anti-HBV drug development or for novel therapies.
文摘Let (M^3+k, T) be an involution on a closed manifold such that its fixed point set is L^1 (p).In this paper, we determine the existence of (M^3+k, T) and give the equivariant bordism classification of such involutions.
基金Supported by the Innovation Project for University Prominent Research Talents of Henan (2003KJCX008)
文摘This paper deals with two parabolic initial-boundary value problems in multidimensional domain. The first problem describes the situation where the spherical medium is static and the nonlinear reaction takes place only at a single point. We show that under some conditions, the solution blows up in finite time and the blow-up set is the whole spherical medium. When the spherical medium is allowed to move in a special space, we investigate another parabolic initial-boundary value problem. It is proved that the blow-up can be avoided if the acceleration of the motion satisfies certain conditions.
文摘OBUECTIVE To screen differentially expressed genes in the development of human glioma and establish a primary molecular classification of glioma based on gene expression using cDNA microarrays.METHODS Brain specimens were obtained from 18 patients with glioma, 10 males and 8 females, ages 14-62 with an average age of 44.4. The total RNAs of these glioma specimens and two specimens of donated brain of normal adults were extracted. BioStarH140S microarrays (including 8,347 old genes and 5,592 novel genes) were adopted and hybridized with probes which were prepared from the total RNAs. Differentially expressed genes between normal tissues and glioma tissues were assayed after scanning cDNA microarrays with ScanArray4000. Northern hybridization and in situ hybridization (ISH) were used to identify functions of novel genes. Those differentially expressed genes were studied with a Hierarchical method and molecular classification of glioma was preliminary carried out.RESULTS Among the 13,939 target genes, there were 1,200 (8.61%) differentially expressed genes, of which 395 (2.83%) were novel genes. A total of 348 genes were up-regulated and 852 genes were down-regulated in the gliomas. The results of bioinformatical analysis, Northern hybridization and ISH revealed that those novel genes were highly associated with gliomas. There were multiple genes, such as the MAP gene,cytoskeleton & matrix motility genes, etc, which were of relevance to classification by the Hierarchical method. Molecular classification of glioma using a Hierarchical cluster was in accordance with pathology and suggested a molecular process of tumorigenesis and development.CONCLUSION Multiple genes play important roles in development of glioma, cDNA microarray technology is a powerful technique in screening for differentially expressed genes between two different kinds of tissues. Further analysis of gene expression and novel genes would be helpful to understand the molecular mechanism of glioma development.
