AIM: To study the abnormal cytokeratin (CK) expression,emergence of CK19 with or without CK7, in liver parenchymal cells and the role of laminin (LN), a basement membrane protein, in this process.METHODS: Six hepatoce...AIM: To study the abnormal cytokeratin (CK) expression,emergence of CK19 with or without CK7, in liver parenchymal cells and the role of laminin (LN), a basement membrane protein, in this process.METHODS: Six hepatocellular carcinoma (HCC) cell lines were examined for different CKs, LN and its receptor by immunocytochemistry and Western blotting. Double immunofluorescent reaction, laser-scanning confocal microscopy and an in vitro induction procedure were used to demonstrate the role of LN in regulating CK19 expression in these cells.RESULTS: Immunoreactivities for CK8, CK18, CK7 and the receptor for LN were observed in all the six HCC cell lines examined. However, CK19 was merely found in four of the six cell lines, and was in any case associated with LN expression. Laser-scanning confocal microscopydemonstrated the concomitant presence of these two molecules in most of the positive cells. In the two HCC cell lines, originally negative for CK19, addition of LN to the culture medium resulted in an induction of CK19 in a dosedependent manner. Both the artificially induced and the intrinsic production of CK19 were completely blocked by an antibody to LN.CONCLUSION: LN can induce expression of CK19 in HCC cells in vitro, providing direct evidence for our hypothesis that the abnormal hepatocytic CK19 expression in situ is due to pathologic LN deposition.展开更多
AIM: To investigate the expression of gonadotropin-releasing hormone (GnRH) receptor and the effects of GnRH analog(alarelin) on proliferation of cultured gastric smooth muscle cells (GSMC) of rats. METHODS: Immunohis...AIM: To investigate the expression of gonadotropin-releasing hormone (GnRH) receptor and the effects of GnRH analog(alarelin) on proliferation of cultured gastric smooth muscle cells (GSMC) of rats. METHODS: Immunohistochemical ABC methods and in situ hybridization methods were used to dectect protein and mRNA expression of GnRH receptor in GSMC, respectively. Techniques of cell culture, OD value of MTT test, measure of ^3H-TdR incorporation, average fluorescent values of proliferating cell nuclear antigen (PCNA) and flow cytometric DNA analysis were used in the experiment. RESULTS: The cultured GSMC of rats showed immunoreactivity for GnRH receptor; positive staining was located in cytoplasm. GnRH receptor mRNA hybridized signals were also detected in cytoplasm. When alarelin (10^-9, 10^-7, 10^-5 mol/L) was administered into the medium and incubated for 24 h, OD value of MTT, ^3H-TdR incorporation and average fluorescent values of PCNA all decreased significantly as compared with the control group (P<0.05). The maximum inhibitory effect on cell proliferation was achieved a concentration of 10s mol/L and it acted in a dose-dependent manner. Flow cytometric DNA analysis revealed that alarelin could significantly enhance ratio of G1 phase and decrease ratio of S phase of GSMC of rats (P<0.05).The maximum inhibitory effect on ratio of S phase was at the concentration of 10-s mol/L and also acted in a dose-dependent manner. CONCLUSION: Our data suggest that GnRH receptor can be expressed by GSMC of rats. GnRH analogue can directly inhibit proliferation and DNA synthesis of rat GSMC through GnRH receptors.展开更多
AIM: To transfect murine angiostatin cDNA into human hepatocellular carcinoma cell line SMMC-7721 and to investigate its effects on implanted carcinoma in nude mice.METHODS: A eukaryotic expression vector of pcDNA3.1-...AIM: To transfect murine angiostatin cDNA into human hepatocellular carcinoma cell line SMMC-7721 and to investigate its effects on implanted carcinoma in nude mice.METHODS: A eukaryotic expression vector of pcDNA3.1-mAST containing murine angiostatin was constructed. Then pcDNA3.1-mAST plasmid was transfected into cell line SMMC-7721 by Lipofectamine. The resistant clone was screened by G418 filtration and identified by RT-PCR and Western blotting. Nude mice were divided into three groups of 10 each. Mice in blank control group were only injected with SMMC-7721 cells. Mice in vector control group were injected with SMMC-7721 cells transfected with pcDNA3.1 (+) vector,whereas mice in angiostatin group were injected with SMMC-7721 cells transfected with pcDNA3.1-mAST plasmid.Volume, mass and microvessel density (MVD) of the tumors in different groups were measured and compared.RESULTS: Murine angiostatin cDNA was successfully cloned into the eukaryotic expression vector pcDNA3.1 (+). pcDNA3.1-mAST was successfully transfected into SMMC-7721 cell line and showed stable expression in this cell line.No significant difference was observed in the growth speed of SMMC-7721 cells between groups transfected with and without angiostatin cDNA. Tumor volume, mass and MVD in the angiostatin group were significantly lower than those in the blank control group and vector control group (P<0.01).The inhibitory rate of tumor reached 78.6%. Mass and MVD of the tumors only accounted for 34.6% and 48.9% respectively of those in the blank control group.CONCLUSION: Angiostatin cDNA could be stably expressed in human hepatocellular carcinoma cell line SMMC-7721 without obvious inhibitory effects on the growth of SMMC-7721 cells. When implanted into nude mice, SMMC-7721 cells transfected with angiostatin cDNA show a decreased tumorigenic capability. It suggests that angiostatin can inhibit tumor growth through its inhibition on angiogenesis in tumors.展开更多
The similarity and classification of sucking louse communities on 24 species of small mammals were studied in Yunnan Province, China, through a hierarchical cluster analysis. All the louse species on the body surface ...The similarity and classification of sucking louse communities on 24 species of small mammals were studied in Yunnan Province, China, through a hierarchical cluster analysis. All the louse species on the body surface of a certain species of small mammals are regarded as a louse community unit. The results reveal that the community structure of sucking lice on small mammals is simple with low species diversity. Most small mammals usually have certain louse species on their body surface; there exists a high degree of host specificity. Most louse communities on the same genus of small mammals show a high similarity and are classified into the same group based on hierarchical cluster analysis. When the hosts have a close affinity in taxonomy, the louse communities on their body surface would tend to be similar with the same or similar dominant louse species (as observed in genus Rattus, Niviventer, Apodemus and Eothenomys). The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. The results suggest a close relationship of co-evolution between sucking lice and their hosts.展开更多
On the basis of investigating 9 counties (towns) in Yunnan Province of China, the species diversity and community structure of sucking lice on the body surface of small mammal hosts are studied in the paper. Species r...On the basis of investigating 9 counties (towns) in Yunnan Province of China, the species diversity and community structure of sucking lice on the body surface of small mammal hosts are studied in the paper. Species richness (S) is used to stand for the species diversity. The calculation of community diversity index and evenness are based on Shannon-Wiener's method. 2745 small mammals captured from the investigated sites belong to 10 families, 25 genera and 41 species in 5 orders (Rodentia, Insectivora, Scandentia, Logomorpha and Carnivora) while 18165 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 4 families, 6 genera and 22 species. The species of sucking lice are much less than the species of their hosts. Most species of small mammals have their fixed sucking lice on their body surface. One species of small mammals usually have few species of sucking lice (1 to 4 species). The close species of the hosts in the taxonomy are found to have the same or similar dominant species of sucking lice on their body surface. The results reveal that the species diversity of sucking lice on small mammals is very low with a very simple community structure. The results also imply there may be a close co-evolution relationship between the lice and the hosts.展开更多
基金the Natural Science Foundation of China(NSFC), Grants No.39470778 and No.30171052
文摘AIM: To study the abnormal cytokeratin (CK) expression,emergence of CK19 with or without CK7, in liver parenchymal cells and the role of laminin (LN), a basement membrane protein, in this process.METHODS: Six hepatocellular carcinoma (HCC) cell lines were examined for different CKs, LN and its receptor by immunocytochemistry and Western blotting. Double immunofluorescent reaction, laser-scanning confocal microscopy and an in vitro induction procedure were used to demonstrate the role of LN in regulating CK19 expression in these cells.RESULTS: Immunoreactivities for CK8, CK18, CK7 and the receptor for LN were observed in all the six HCC cell lines examined. However, CK19 was merely found in four of the six cell lines, and was in any case associated with LN expression. Laser-scanning confocal microscopydemonstrated the concomitant presence of these two molecules in most of the positive cells. In the two HCC cell lines, originally negative for CK19, addition of LN to the culture medium resulted in an induction of CK19 in a dosedependent manner. Both the artificially induced and the intrinsic production of CK19 were completely blocked by an antibody to LN.CONCLUSION: LN can induce expression of CK19 in HCC cells in vitro, providing direct evidence for our hypothesis that the abnormal hepatocytic CK19 expression in situ is due to pathologic LN deposition.
基金Supported by the Natural Science Foundation of China,No.39770388
文摘AIM: To investigate the expression of gonadotropin-releasing hormone (GnRH) receptor and the effects of GnRH analog(alarelin) on proliferation of cultured gastric smooth muscle cells (GSMC) of rats. METHODS: Immunohistochemical ABC methods and in situ hybridization methods were used to dectect protein and mRNA expression of GnRH receptor in GSMC, respectively. Techniques of cell culture, OD value of MTT test, measure of ^3H-TdR incorporation, average fluorescent values of proliferating cell nuclear antigen (PCNA) and flow cytometric DNA analysis were used in the experiment. RESULTS: The cultured GSMC of rats showed immunoreactivity for GnRH receptor; positive staining was located in cytoplasm. GnRH receptor mRNA hybridized signals were also detected in cytoplasm. When alarelin (10^-9, 10^-7, 10^-5 mol/L) was administered into the medium and incubated for 24 h, OD value of MTT, ^3H-TdR incorporation and average fluorescent values of PCNA all decreased significantly as compared with the control group (P<0.05). The maximum inhibitory effect on cell proliferation was achieved a concentration of 10s mol/L and it acted in a dose-dependent manner. Flow cytometric DNA analysis revealed that alarelin could significantly enhance ratio of G1 phase and decrease ratio of S phase of GSMC of rats (P<0.05).The maximum inhibitory effect on ratio of S phase was at the concentration of 10-s mol/L and also acted in a dose-dependent manner. CONCLUSION: Our data suggest that GnRH receptor can be expressed by GSMC of rats. GnRH analogue can directly inhibit proliferation and DNA synthesis of rat GSMC through GnRH receptors.
文摘AIM: To transfect murine angiostatin cDNA into human hepatocellular carcinoma cell line SMMC-7721 and to investigate its effects on implanted carcinoma in nude mice.METHODS: A eukaryotic expression vector of pcDNA3.1-mAST containing murine angiostatin was constructed. Then pcDNA3.1-mAST plasmid was transfected into cell line SMMC-7721 by Lipofectamine. The resistant clone was screened by G418 filtration and identified by RT-PCR and Western blotting. Nude mice were divided into three groups of 10 each. Mice in blank control group were only injected with SMMC-7721 cells. Mice in vector control group were injected with SMMC-7721 cells transfected with pcDNA3.1 (+) vector,whereas mice in angiostatin group were injected with SMMC-7721 cells transfected with pcDNA3.1-mAST plasmid.Volume, mass and microvessel density (MVD) of the tumors in different groups were measured and compared.RESULTS: Murine angiostatin cDNA was successfully cloned into the eukaryotic expression vector pcDNA3.1 (+). pcDNA3.1-mAST was successfully transfected into SMMC-7721 cell line and showed stable expression in this cell line.No significant difference was observed in the growth speed of SMMC-7721 cells between groups transfected with and without angiostatin cDNA. Tumor volume, mass and MVD in the angiostatin group were significantly lower than those in the blank control group and vector control group (P<0.01).The inhibitory rate of tumor reached 78.6%. Mass and MVD of the tumors only accounted for 34.6% and 48.9% respectively of those in the blank control group.CONCLUSION: Angiostatin cDNA could be stably expressed in human hepatocellular carcinoma cell line SMMC-7721 without obvious inhibitory effects on the growth of SMMC-7721 cells. When implanted into nude mice, SMMC-7721 cells transfected with angiostatin cDNA show a decreased tumorigenic capability. It suggests that angiostatin can inhibit tumor growth through its inhibition on angiogenesis in tumors.
文摘The similarity and classification of sucking louse communities on 24 species of small mammals were studied in Yunnan Province, China, through a hierarchical cluster analysis. All the louse species on the body surface of a certain species of small mammals are regarded as a louse community unit. The results reveal that the community structure of sucking lice on small mammals is simple with low species diversity. Most small mammals usually have certain louse species on their body surface; there exists a high degree of host specificity. Most louse communities on the same genus of small mammals show a high similarity and are classified into the same group based on hierarchical cluster analysis. When the hosts have a close affinity in taxonomy, the louse communities on their body surface would tend to be similar with the same or similar dominant louse species (as observed in genus Rattus, Niviventer, Apodemus and Eothenomys). The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. The results suggest a close relationship of co-evolution between sucking lice and their hosts.
文摘On the basis of investigating 9 counties (towns) in Yunnan Province of China, the species diversity and community structure of sucking lice on the body surface of small mammal hosts are studied in the paper. Species richness (S) is used to stand for the species diversity. The calculation of community diversity index and evenness are based on Shannon-Wiener's method. 2745 small mammals captured from the investigated sites belong to 10 families, 25 genera and 41 species in 5 orders (Rodentia, Insectivora, Scandentia, Logomorpha and Carnivora) while 18165 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 4 families, 6 genera and 22 species. The species of sucking lice are much less than the species of their hosts. Most species of small mammals have their fixed sucking lice on their body surface. One species of small mammals usually have few species of sucking lice (1 to 4 species). The close species of the hosts in the taxonomy are found to have the same or similar dominant species of sucking lice on their body surface. The results reveal that the species diversity of sucking lice on small mammals is very low with a very simple community structure. The results also imply there may be a close co-evolution relationship between the lice and the hosts.
