In liver,the most intensively studied transmembrane and intracellular signal transduction pathways are the Janus kinase signal transduction pathway,the mitogen-activated protein kinases signal transduction pathway,the...In liver,the most intensively studied transmembrane and intracellular signal transduction pathways are the Janus kinase signal transduction pathway,the mitogen-activated protein kinases signal transduction pathway,the transforming growth factor β signal transduction pathway,the tumor necrosis factor α signal transduction pathway and the recently discovered sphingolipid signal transduction pathway.All of them are activated by many different cytokines and growth factors.They regulate specific cell mechanisms such as hepatocytes proliferation,growth,differentiation,adhesion,apoptosis,and synthesis and degradation of the extracellular matrix.The replication cycle of hepatitis C virus(HCV) is intracellular and requires signal transduction to the nucleus to regulate transcription of its genes.Moreover,HCV itself,by its structural and non-structural proteins,could influence the activity of the second signal messengers.Thus,the inhibition of the transmembrane and intracellular signal transduction pathways could be a new therapeutic target in chronic hepatitis C treatment.展开更多
AIM: To transfer human HGF gene into the liver of rats by direct electroporation as a means to prevent radiationinduced liver damage.METHODS: Rat whole liver irradiation model was accomplished by intra-operative appro...AIM: To transfer human HGF gene into the liver of rats by direct electroporation as a means to prevent radiationinduced liver damage.METHODS: Rat whole liver irradiation model was accomplished by intra-operative approach. HGF plasmid was injected into liver and transferred by electroporation using a pulse generator. Control rats (n = 8) received electrogene therapy (EGT) vehicle plasmid and another 8rats received HGF-EGT 100 μg 48 h before WLIR.Expression of HGF in liver was examined by RT-PCR and ELISA methods. Apoptosis was determined by TUNEL assay. Histopathology was evaluated 10 wk after whole liver irradiation.RESULTS: Marked decrease of apoptotic cells and downregulation of transforming growth factor-beta 1 (TGF-β1)mRNA were observed in the HGF-EGT group 2 d after liver irradiation compared to control animals. Less evidence of radiation-induced liver damage was observed morphologically in liver specimen 10 wk after liver irradiation and longer median survival time was observed from HGF-EGT group (14 wk) compared to control rats (5 wk). (P = 0.031).CONCLUSION: For the first time it has been demonstrated that HGF-EGT would prevent liver from radiation-induced liver damage by preventing apoptosis and down-regulation of TGF-β1.展开更多
AIM： To evaluate hepatic recurrence and prognostic factors for survival in patients with surgically resected hilar cholangiocarcinoma in a single institution over the last 13 years. METHODS： From 1994 to 2007, all p...AIM： To evaluate hepatic recurrence and prognostic factors for survival in patients with surgically resected hilar cholangiocarcinoma in a single institution over the last 13 years. METHODS： From 1994 to 2007, all patients with hilar cholangiocarcinoma referred to a surgical clinic were evaluated. Demographic data, tumor characteristics, and outcome were analyzed retrospectively. Outcome was compared in patients who underwent additional liver resection with resection of the tumor. RESULTS： Of the 69 patients submitted to laparotomy for tumor resection, curative resection （Ro resection） was performed in 40 patients, and palliative resection in 29. Thirty-one patients had only duct resection, and 38 patients had combined duct resection with liver resection including 34 total or part caudate lobes. Curative rates with the combined hepatectomy were significantly improved compared with those without additional hepatectomy （27/38 vs 13/31; X^2 = 5.94, P 〈 0.05）. Concomitant liver resection was associated with a decreased incidence of initial recurrence in liver one year after surgery （11/38 vs 23/31; X^2 = 13.98, P 〈 0.01）. The 3-year survival rate after Ro resection was 30.7% and was 10.5% for palliative resection. R0 resection improved the 3-year survival rate （30.7% vs 10.5%; X^2 = 12.47, P 〈 0.01）.CONCLUSION： Hepatectomy, especially including the caudate lobe combined with bile duct resection should be considered standard treatment to cure hilar cholangiocarcinoma.展开更多
The iodination efficiency of salmon GH(sGH) was 38.82%,using a modification of the chloramine T method. The specific activity of the 125 I sGH was about 40 μCi/μg protein. The results of binding assay showed a singl...The iodination efficiency of salmon GH(sGH) was 38.82%,using a modification of the chloramine T method. The specific activity of the 125 I sGH was about 40 μCi/μg protein. The results of binding assay showed a single class of high affinity and low capacity binding site in flounder liver. Long term administration with exogenous GH can induce the up regulation of hepatic GH receptor in total binding capacity though there was no significant difference of association constant among any groups. Considering that there was no significant difference in capacity of free binding sites of livers from control and experimental fish, this result also indicated that the liver from experimental fish, compared to that from control fish, had more occupied binding sites.展开更多
AIM： To elucidate the role of neuropilin-1 （Nrp-1） and semaphorin 3A （Sema3A） in sinusoidal remodeling dur- ing liver regeneration in rats. METHODS： Male Wistar/ST rats at 7 wk of age, weigh- ing about 200 g, we...AIM： To elucidate the role of neuropilin-1 （Nrp-1） and semaphorin 3A （Sema3A） in sinusoidal remodeling dur- ing liver regeneration in rats. METHODS： Male Wistar/ST rats at 7 wk of age, weigh- ing about 200 g, were used for all animal experiments. In vivo, at 24, 48, 72, 96, 144 and 192 h after two- thirds partial hepatectomy （PHx）, the remnant livers were removed. Liver tissues were immunohistochemi- cally stained for Nrp-1, Sema3A and SE-1, a liver sinu- soidal endothelial cell （SEC） marker. Total RNA of the liver tissue was extracted and reversely transcribed into cDNA. The mRNA expression of Sema3A was ana- lyzed by quantitative real-time polymerase chain reac- tion and normalized to that of ribosomal protein $18. In vitro, SECs were isolated from rat liver and cultured in endothelial growth medium containing 20 ng/mL vascular endothelial cell growth factor. Migration of SECs in primary culture was assessed by cell transwell assay with or without recombinant Sema3A. Apoptotic cells were determined by a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling method. RESULTS： In vitro, immunohistochemistry study re- vealed that Sema3A and Nrp-1 were constitutively ex- pressed in hepatocytes and SECs, respectively, in normal rat liver tissues. Nrp-1 expression in SECs was quantified by the percentage of immunostained area with anti- Nrp-1 antibody in relation to the area stained with SE-1. Between 24 h and 96 h following resection of liver, Nrp-1 expression in SECs was transiently increased. Compared with the baseline （5.2% ± 0.1%）, Nrp-1 expression in SECs significantly increased at 24 h （17.3% ± 0.7%, P 〈 0.05）, 48 h （39.1% ± 0.6%, P 〈 0.01）, 72 h （46.9% ± 4.5%, P 〈 0.01） and 96 h （29.9% ±3.8%, P 〈 0.01） after PHx, then returned to the basal level at termination of liver regeneration. Interestingly, the expression of Sema3A was inversely associated with that of Nrp-1 in liver after PHx. Sema3A mRNA expres- sion was significantly reduced by about 75% over the period 24-144 h after PHx （P 〈 0.05）, and returned to basal levels at 192 h after PHx. In vitro, SECs isolated from rats after PHx （PHx-SECs） were observed to mi- grate to the lower chamber of the cell transwell system after incubation for 24 h, but not cells from normal rats （CONT-SECs）, indicating that mobility of PHx-SECs increases as compared with that of CONT-SECs. More- over, recombinant Sema3A significantly attenuated mi- gration in PHx-SECs in primary culture （vehicle-treated 100% ± 7.9% vs Sema3A-treated 42.6% ± 5.4%, P 〈 0.01）, but not in CONT-SECs. Compared with CONT- SECs, the apoptotic rate of PHx-SECs decreased by 78.3% （P 〈 0.05）. There was no difference in apopto- sis between CONT-SECs that were treated with vehicle and Sema3A. However, in PHx-SECs, apoptosis was induced by the presence of 5 nmol Sema3A for 24 h （vehicle-treated 21.7%±7.6% vs Sema3A-treated 104.3% ± 8.9%, P 〈 0.05）. In addition, immunohisto- chemistry confirmed the increased expression of Nrp-1 in PHx-SECs, while it was noted to a lesser extent in CONT-SECs. CONCLUSION： The interplay of Nrp-1 and Sema3A shown in our results may lead to a better understand- ing of interaction between sinusoidal remodeling and SECs during liver regeneration.展开更多
Objective: Angiogenesis is a crucial step for tumor growth and progression. Changes of liver angiogenesis (without metastatic invasion) in response to primary tumors are not known. The aim of the study was to investig...Objective: Angiogenesis is a crucial step for tumor growth and progression. Changes of liver angiogenesis (without metastatic invasion) in response to primary tumors are not known. The aim of the study was to investigate the liver angiogenesis in non-metastatic colorectal cancer (CRC). Methods: Human colorectal adenocarcinoma tumors were grown subcutaneously in nude mice. All animals showed tumor growth locally without macroscopic or microscopic evidence of liver metastases. Livers were investigated for their microvessel density (MVD) at different stages of tumor growth (as small, medium, and large-sized tumors). Normal non-tumor-bearing mice served as controls. To assess MVD, two endothelial cell markers (anti-CD34 and -CD31 antibodies), image analysis, and immunofluorescent technique were utilized. Enumeration of positive stained endothelial cells revealed the MVD. Results: Non-metastatic livers showed increased levels of MVD vs. control. Moreover, levels of MVD were higher in small and medium-sized tumor groups versus large sized tumor groups. Conclusion: The present data indicate that angiogenesis in the liver is induced in early-stages of CRC. However, this effect is suppressed with advanced tumor growth. These results provide an additional rationale for including antiangiogenic therapy in the treatment of early stages of CRC.展开更多
Objective: To investigate the expression and pattern of vascular endothelial growth factor (VEGF) and its fetal liver kinase-1 (Flk-1) receptor in spinal cord and dorsal root ganglia after neurotomy of sciatic nerve i...Objective: To investigate the expression and pattern of vascular endothelial growth factor (VEGF) and its fetal liver kinase-1 (Flk-1) receptor in spinal cord and dorsal root ganglia after neurotomy of sciatic nerve in rats. Methods: Forty-five adult male Wistar rats were divided randomly into a control group (n=5) and an experimental group (n=40). The bilateral sciatic nerves of the rats in the experimental group underwent neurotomy and the L 4-L 6 spinal cord and the corresponding dorsal root ganglia were harvested respectively at 8 hours, and 1, 3, 5, 7, 10, 14 and 21 days (8 subgroups with 5 rats each) after operation. The rats in the control group only underwent an exposure of sciatic nerve without neurotomy. Immunohistochemistry and image analysis were used to study the expression of VEGF and its Flk-1 receptor. Results: Both VEGF and Flk-1 receptor expressed in the normal rat spinal cord and dorsal root ganglia. In response to neurotomy, their expression reached a higher level and persisted for a short time then declined to the normal level rapidly. Besides, positive staining of Flk-1 was observed in both glial cells and nerve fibers, which located in the white matter of the spinal cord.Conclusions: VEGF can promote the regeneration of peripheral nerves from the angle of central neurons, which establishes the experimental and theoretical foundation for VEGF treating peripheral nerve injuries.展开更多
文摘In liver,the most intensively studied transmembrane and intracellular signal transduction pathways are the Janus kinase signal transduction pathway,the mitogen-activated protein kinases signal transduction pathway,the transforming growth factor β signal transduction pathway,the tumor necrosis factor α signal transduction pathway and the recently discovered sphingolipid signal transduction pathway.All of them are activated by many different cytokines and growth factors.They regulate specific cell mechanisms such as hepatocytes proliferation,growth,differentiation,adhesion,apoptosis,and synthesis and degradation of the extracellular matrix.The replication cycle of hepatitis C virus(HCV) is intracellular and requires signal transduction to the nucleus to regulate transcription of its genes.Moreover,HCV itself,by its structural and non-structural proteins,could influence the activity of the second signal messengers.Thus,the inhibition of the transmembrane and intracellular signal transduction pathways could be a new therapeutic target in chronic hepatitis C treatment.
基金Supported by National Science Council grant NSC-91-275-9075-001 for the development of Boron Neutron Capture Therapy for Hepatoma Treatment
文摘AIM: To transfer human HGF gene into the liver of rats by direct electroporation as a means to prevent radiationinduced liver damage.METHODS: Rat whole liver irradiation model was accomplished by intra-operative approach. HGF plasmid was injected into liver and transferred by electroporation using a pulse generator. Control rats (n = 8) received electrogene therapy (EGT) vehicle plasmid and another 8rats received HGF-EGT 100 μg 48 h before WLIR.Expression of HGF in liver was examined by RT-PCR and ELISA methods. Apoptosis was determined by TUNEL assay. Histopathology was evaluated 10 wk after whole liver irradiation.RESULTS: Marked decrease of apoptotic cells and downregulation of transforming growth factor-beta 1 (TGF-β1)mRNA were observed in the HGF-EGT group 2 d after liver irradiation compared to control animals. Less evidence of radiation-induced liver damage was observed morphologically in liver specimen 10 wk after liver irradiation and longer median survival time was observed from HGF-EGT group (14 wk) compared to control rats (5 wk). (P = 0.031).CONCLUSION: For the first time it has been demonstrated that HGF-EGT would prevent liver from radiation-induced liver damage by preventing apoptosis and down-regulation of TGF-β1.
基金Professor Development Fund of Fujian Medical University
文摘AIM： To evaluate hepatic recurrence and prognostic factors for survival in patients with surgically resected hilar cholangiocarcinoma in a single institution over the last 13 years. METHODS： From 1994 to 2007, all patients with hilar cholangiocarcinoma referred to a surgical clinic were evaluated. Demographic data, tumor characteristics, and outcome were analyzed retrospectively. Outcome was compared in patients who underwent additional liver resection with resection of the tumor. RESULTS： Of the 69 patients submitted to laparotomy for tumor resection, curative resection （Ro resection） was performed in 40 patients, and palliative resection in 29. Thirty-one patients had only duct resection, and 38 patients had combined duct resection with liver resection including 34 total or part caudate lobes. Curative rates with the combined hepatectomy were significantly improved compared with those without additional hepatectomy （27/38 vs 13/31; X^2 = 5.94, P 〈 0.05）. Concomitant liver resection was associated with a decreased incidence of initial recurrence in liver one year after surgery （11/38 vs 23/31; X^2 = 13.98, P 〈 0.01）. The 3-year survival rate after Ro resection was 30.7% and was 10.5% for palliative resection. R0 resection improved the 3-year survival rate （30.7% vs 10.5%; X^2 = 12.47, P 〈 0.01）.CONCLUSION： Hepatectomy, especially including the caudate lobe combined with bile duct resection should be considered standard treatment to cure hilar cholangiocarcinoma.
文摘The iodination efficiency of salmon GH(sGH) was 38.82%,using a modification of the chloramine T method. The specific activity of the 125 I sGH was about 40 μCi/μg protein. The results of binding assay showed a single class of high affinity and low capacity binding site in flounder liver. Long term administration with exogenous GH can induce the up regulation of hepatic GH receptor in total binding capacity though there was no significant difference of association constant among any groups. Considering that there was no significant difference in capacity of free binding sites of livers from control and experimental fish, this result also indicated that the liver from experimental fish, compared to that from control fish, had more occupied binding sites.
基金Supported by A Grant-in-aid for Young Scientists from Japan Society for the Promotion of Science,No.22790671
文摘AIM： To elucidate the role of neuropilin-1 （Nrp-1） and semaphorin 3A （Sema3A） in sinusoidal remodeling dur- ing liver regeneration in rats. METHODS： Male Wistar/ST rats at 7 wk of age, weigh- ing about 200 g, were used for all animal experiments. In vivo, at 24, 48, 72, 96, 144 and 192 h after two- thirds partial hepatectomy （PHx）, the remnant livers were removed. Liver tissues were immunohistochemi- cally stained for Nrp-1, Sema3A and SE-1, a liver sinu- soidal endothelial cell （SEC） marker. Total RNA of the liver tissue was extracted and reversely transcribed into cDNA. The mRNA expression of Sema3A was ana- lyzed by quantitative real-time polymerase chain reac- tion and normalized to that of ribosomal protein $18. In vitro, SECs were isolated from rat liver and cultured in endothelial growth medium containing 20 ng/mL vascular endothelial cell growth factor. Migration of SECs in primary culture was assessed by cell transwell assay with or without recombinant Sema3A. Apoptotic cells were determined by a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling method. RESULTS： In vitro, immunohistochemistry study re- vealed that Sema3A and Nrp-1 were constitutively ex- pressed in hepatocytes and SECs, respectively, in normal rat liver tissues. Nrp-1 expression in SECs was quantified by the percentage of immunostained area with anti- Nrp-1 antibody in relation to the area stained with SE-1. Between 24 h and 96 h following resection of liver, Nrp-1 expression in SECs was transiently increased. Compared with the baseline （5.2% ± 0.1%）, Nrp-1 expression in SECs significantly increased at 24 h （17.3% ± 0.7%, P 〈 0.05）, 48 h （39.1% ± 0.6%, P 〈 0.01）, 72 h （46.9% ± 4.5%, P 〈 0.01） and 96 h （29.9% ±3.8%, P 〈 0.01） after PHx, then returned to the basal level at termination of liver regeneration. Interestingly, the expression of Sema3A was inversely associated with that of Nrp-1 in liver after PHx. Sema3A mRNA expres- sion was significantly reduced by about 75% over the period 24-144 h after PHx （P 〈 0.05）, and returned to basal levels at 192 h after PHx. In vitro, SECs isolated from rats after PHx （PHx-SECs） were observed to mi- grate to the lower chamber of the cell transwell system after incubation for 24 h, but not cells from normal rats （CONT-SECs）, indicating that mobility of PHx-SECs increases as compared with that of CONT-SECs. More- over, recombinant Sema3A significantly attenuated mi- gration in PHx-SECs in primary culture （vehicle-treated 100% ± 7.9% vs Sema3A-treated 42.6% ± 5.4%, P 〈 0.01）, but not in CONT-SECs. Compared with CONT- SECs, the apoptotic rate of PHx-SECs decreased by 78.3% （P 〈 0.05）. There was no difference in apopto- sis between CONT-SECs that were treated with vehicle and Sema3A. However, in PHx-SECs, apoptosis was induced by the presence of 5 nmol Sema3A for 24 h （vehicle-treated 21.7%±7.6% vs Sema3A-treated 104.3% ± 8.9%, P 〈 0.05）. In addition, immunohisto- chemistry confirmed the increased expression of Nrp-1 in PHx-SECs, while it was noted to a lesser extent in CONT-SECs. CONCLUSION： The interplay of Nrp-1 and Sema3A shown in our results may lead to a better understand- ing of interaction between sinusoidal remodeling and SECs during liver regeneration.
文摘Objective: Angiogenesis is a crucial step for tumor growth and progression. Changes of liver angiogenesis (without metastatic invasion) in response to primary tumors are not known. The aim of the study was to investigate the liver angiogenesis in non-metastatic colorectal cancer (CRC). Methods: Human colorectal adenocarcinoma tumors were grown subcutaneously in nude mice. All animals showed tumor growth locally without macroscopic or microscopic evidence of liver metastases. Livers were investigated for their microvessel density (MVD) at different stages of tumor growth (as small, medium, and large-sized tumors). Normal non-tumor-bearing mice served as controls. To assess MVD, two endothelial cell markers (anti-CD34 and -CD31 antibodies), image analysis, and immunofluorescent technique were utilized. Enumeration of positive stained endothelial cells revealed the MVD. Results: Non-metastatic livers showed increased levels of MVD vs. control. Moreover, levels of MVD were higher in small and medium-sized tumor groups versus large sized tumor groups. Conclusion: The present data indicate that angiogenesis in the liver is induced in early-stages of CRC. However, this effect is suppressed with advanced tumor growth. These results provide an additional rationale for including antiangiogenic therapy in the treatment of early stages of CRC.
文摘Objective: To investigate the expression and pattern of vascular endothelial growth factor (VEGF) and its fetal liver kinase-1 (Flk-1) receptor in spinal cord and dorsal root ganglia after neurotomy of sciatic nerve in rats. Methods: Forty-five adult male Wistar rats were divided randomly into a control group (n=5) and an experimental group (n=40). The bilateral sciatic nerves of the rats in the experimental group underwent neurotomy and the L 4-L 6 spinal cord and the corresponding dorsal root ganglia were harvested respectively at 8 hours, and 1, 3, 5, 7, 10, 14 and 21 days (8 subgroups with 5 rats each) after operation. The rats in the control group only underwent an exposure of sciatic nerve without neurotomy. Immunohistochemistry and image analysis were used to study the expression of VEGF and its Flk-1 receptor. Results: Both VEGF and Flk-1 receptor expressed in the normal rat spinal cord and dorsal root ganglia. In response to neurotomy, their expression reached a higher level and persisted for a short time then declined to the normal level rapidly. Besides, positive staining of Flk-1 was observed in both glial cells and nerve fibers, which located in the white matter of the spinal cord.Conclusions: VEGF can promote the regeneration of peripheral nerves from the angle of central neurons, which establishes the experimental and theoretical foundation for VEGF treating peripheral nerve injuries.
