AIM: To investigate the differences in biological features of gastric dysplasia (Dys), indefinite dysplasia (IDys) and reactive hyperplasia (RH) by studying the biomarker alterations in cell proliferation, cell differ...AIM: To investigate the differences in biological features of gastric dysplasia (Dys), indefinite dysplasia (IDys) and reactive hyperplasia (RH) by studying the biomarker alterations in cell proliferation, cell differentiation, cell cycle control and the expression of house-keeping genes, and further to search for markers which could be used in guiding the pathological diagnosis of three lesions. METHODS: Expressions of MUC5AC, MUC6, adenomatous polyposis coli (APC), p53, Ki-67, proliferation cell nuclear antigen (PCNA) and EGFR were studied by immunohistochemistry with a standard Envision technique in formalinfixed and paraffin-embedded specimens from 43 RH, 35 IDys, 35 Dys and 36 intestinal type gastric carcinomas (IGC). In addition, Bayes discriminant analysis was used to investigate the value of markers studied in differential diagnosis of RH, IDys, Dys and IGC. RESULTS: The MUC5AC and MUC6 antigen expressions in RH, IDys, Dys and IGC decreased gradually (MUC5AC:86.04%, 77.14%, 28.57%, 6.67%; MUC6: 65.15%, 54.29%, 20.00%, 25.00%, respectively). The expressions of the two markers had no significant difference between RH and IDys, but were all significantly higher than those ofthe other two lesions (MUC5AC: x2 = 27.607, 38.027 and 17.33, 26.092; MUC6: x2= 16.54, 12.665 and 9.282, 6.737, P＜0.01). There was no significant differencebetween RH and IDys, Dys and IGC in MUC6 expression. The APC gene expression in the four lesions had a similar decreasing tendency (RH 69.76%, IDys 68.57%, Dys39.39%, IGC 22.86%), and it was significantly higher in the first two lesions than in the last two (x2 = 7.011,16.995 and 14.737, 19.817, P＜0.05). The p53 expressionin RH, IDys, Dys and IGC was 6.98%, 20%, 57.14% and 50%, respectively. There was no significant differencebetween RH and IDys or Dys and IGC, but the p53 expression in RH and IDys was significantly lower than that in Dys and IGC (x2 = 7.011, 16.995 and 14.737, 19.817, P＜0.01).The Ki-67 label index was significantly different among four lesions (RH: 0.298±8.92%, IDys: 0.358±9.25%,Dys: 0.498±9.03%, IGC: 0.620±10.8%, P＜0.001). Positive immunostaining of PCNA was though observed in all specimens, significant differences were detected among four lesions (F= 95.318, P＜0.01). In addition, we used Bayes discriminant analysis to investigate molecular pathological classification of the lesions, and obtained the best result with the combination of MUC5AC, Ki-67 and PCNA. The overall rate of correct classification was67.4% (RH), 68.6% (IDys), 70.6% (Dys) and 84.8% (IGC), respectively.CONCLUSION: Dys has neoplastic biological characteristics, while RH and IDys display hyperplastic characteristics. MUC5AC and proliferation-related biomarkers (Ki-67, PCNA) are more specific in distinguishing Dys from RH and IDys.展开更多
Short interfering RNA (siRNA) is widely used for studyingpost-transcriptional gene silencing and holds great promise as a tool for both identifying functionof novel genes and validating drug targets. Two siRNA fragmen...Short interfering RNA (siRNA) is widely used for studyingpost-transcriptional gene silencing and holds great promise as a tool for both identifying functionof novel genes and validating drug targets. Two siRNA fragments (siRNA-a and -b), which weredesigned against different specific areas of coding region of the same target green fluorescentprotein (GFP) gene, were used to silence GFP expression in cultured gfp transgenic cells of rice(Oryza sativa L.; OS), cotton (Gossypium hirsutum L.; GH), Eraser fir [Abies fraseri (Pursh) Poir;AF], and Virginia pine (Pinus virginiana Mill.; PV). Differential gene silencing was observed in thebombarded transgenic cells between two siRNAs, and these results were consistent with theinactivation of GFP confirmed by laser scanning microscopy, Northern blot, and siRNA analysis intested transgenic cell cultures. These data suggest that siRNA-mediated gene inactivation can be thesiRNA specific in different plant species. These results indicate that siRNA is a highly specifictool for targeted gene knockdown and for establishing siRNA-mediated gene silencing, which could bea reliable approach for large-scale screening of gene function and drug target validation.展开更多
Genomics promises to enrich the investigations of biology and biochemistry. Current advancements in genomics have major implications for genetic improvement in animals, plants, and microorganisms, and for our understa...Genomics promises to enrich the investigations of biology and biochemistry. Current advancements in genomics have major implications for genetic improvement in animals, plants, and microorganisms, and for our understanding of cell growth, development, differentiation, and communication. Significant progress has been made in the understanding of plant genomics in recent years, and the area continues to progress rapidly. Functional genomics offers enormous potential to tree improvement and the understanding of gene expression in this area of science worldwide. In this review we focus on functional genomics of wood quality and properties in trees, mainly based on progresses made in genomics study of Pinus and Populus. The aims of this review are to summarize the current status of functional genomics including: (1) Gene discovery; (2) EST and genomic sequencing; (3) From EST to functional genomics; (4) Approaches to functional analysis; (5) Engineering lignin biosynthesis; (6) Modification of cell wall biogenesis; and (7) Molecular modelling. Functional genomics has been greatly invested worldwide and will be important in identifying candidate genes whose function is critical to all aspects of plant growth, development, differentiation, and defense. Forest biotechnology industry will significantly benefit from the advent of functional genomics of wood quality and properties.展开更多
基金Supported by the National Key Fundamental Research Project,No.G1998051203
文摘AIM: To investigate the differences in biological features of gastric dysplasia (Dys), indefinite dysplasia (IDys) and reactive hyperplasia (RH) by studying the biomarker alterations in cell proliferation, cell differentiation, cell cycle control and the expression of house-keeping genes, and further to search for markers which could be used in guiding the pathological diagnosis of three lesions. METHODS: Expressions of MUC5AC, MUC6, adenomatous polyposis coli (APC), p53, Ki-67, proliferation cell nuclear antigen (PCNA) and EGFR were studied by immunohistochemistry with a standard Envision technique in formalinfixed and paraffin-embedded specimens from 43 RH, 35 IDys, 35 Dys and 36 intestinal type gastric carcinomas (IGC). In addition, Bayes discriminant analysis was used to investigate the value of markers studied in differential diagnosis of RH, IDys, Dys and IGC. RESULTS: The MUC5AC and MUC6 antigen expressions in RH, IDys, Dys and IGC decreased gradually (MUC5AC:86.04%, 77.14%, 28.57%, 6.67%; MUC6: 65.15%, 54.29%, 20.00%, 25.00%, respectively). The expressions of the two markers had no significant difference between RH and IDys, but were all significantly higher than those ofthe other two lesions (MUC5AC: x2 = 27.607, 38.027 and 17.33, 26.092; MUC6: x2= 16.54, 12.665 and 9.282, 6.737, P＜0.01). There was no significant differencebetween RH and IDys, Dys and IGC in MUC6 expression. The APC gene expression in the four lesions had a similar decreasing tendency (RH 69.76%, IDys 68.57%, Dys39.39%, IGC 22.86%), and it was significantly higher in the first two lesions than in the last two (x2 = 7.011,16.995 and 14.737, 19.817, P＜0.05). The p53 expressionin RH, IDys, Dys and IGC was 6.98%, 20%, 57.14% and 50%, respectively. There was no significant differencebetween RH and IDys or Dys and IGC, but the p53 expression in RH and IDys was significantly lower than that in Dys and IGC (x2 = 7.011, 16.995 and 14.737, 19.817, P＜0.01).The Ki-67 label index was significantly different among four lesions (RH: 0.298±8.92%, IDys: 0.358±9.25%,Dys: 0.498±9.03%, IGC: 0.620±10.8%, P＜0.001). Positive immunostaining of PCNA was though observed in all specimens, significant differences were detected among four lesions (F= 95.318, P＜0.01). In addition, we used Bayes discriminant analysis to investigate molecular pathological classification of the lesions, and obtained the best result with the combination of MUC5AC, Ki-67 and PCNA. The overall rate of correct classification was67.4% (RH), 68.6% (IDys), 70.6% (Dys) and 84.8% (IGC), respectively.CONCLUSION: Dys has neoplastic biological characteristics, while RH and IDys display hyperplastic characteristics. MUC5AC and proliferation-related biomarkers (Ki-67, PCNA) are more specific in distinguishing Dys from RH and IDys.
基金This work was funded by the East Carolina Christmas Tree Program (2002).
文摘Short interfering RNA (siRNA) is widely used for studyingpost-transcriptional gene silencing and holds great promise as a tool for both identifying functionof novel genes and validating drug targets. Two siRNA fragments (siRNA-a and -b), which weredesigned against different specific areas of coding region of the same target green fluorescentprotein (GFP) gene, were used to silence GFP expression in cultured gfp transgenic cells of rice(Oryza sativa L.; OS), cotton (Gossypium hirsutum L.; GH), Eraser fir [Abies fraseri (Pursh) Poir;AF], and Virginia pine (Pinus virginiana Mill.; PV). Differential gene silencing was observed in thebombarded transgenic cells between two siRNAs, and these results were consistent with theinactivation of GFP confirmed by laser scanning microscopy, Northern blot, and siRNA analysis intested transgenic cell cultures. These data suggest that siRNA-mediated gene inactivation can be thesiRNA specific in different plant species. These results indicate that siRNA is a highly specifictool for targeted gene knockdown and for establishing siRNA-mediated gene silencing, which could bea reliable approach for large-scale screening of gene function and drug target validation.
文摘Genomics promises to enrich the investigations of biology and biochemistry. Current advancements in genomics have major implications for genetic improvement in animals, plants, and microorganisms, and for our understanding of cell growth, development, differentiation, and communication. Significant progress has been made in the understanding of plant genomics in recent years, and the area continues to progress rapidly. Functional genomics offers enormous potential to tree improvement and the understanding of gene expression in this area of science worldwide. In this review we focus on functional genomics of wood quality and properties in trees, mainly based on progresses made in genomics study of Pinus and Populus. The aims of this review are to summarize the current status of functional genomics including: (1) Gene discovery; (2) EST and genomic sequencing; (3) From EST to functional genomics; (4) Approaches to functional analysis; (5) Engineering lignin biosynthesis; (6) Modification of cell wall biogenesis; and (7) Molecular modelling. Functional genomics has been greatly invested worldwide and will be important in identifying candidate genes whose function is critical to all aspects of plant growth, development, differentiation, and defense. Forest biotechnology industry will significantly benefit from the advent of functional genomics of wood quality and properties.
