A novel double-layer collagen membrane with unequal pore sizes in each layer was designed and tested in this study. The inner, loose layer has about 100-μm-diameter pores, while the outer, compact layer has about 10-...A novel double-layer collagen membrane with unequal pore sizes in each layer was designed and tested in this study. The inner, loose layer has about 100-μm-diameter pores, while the outer, compact layer has about 10-μm-diameter pores. In a rat model of incomplete spinal cord injury, a large number of neural stem cells were seeded into the loose layer, which was then adhered to the injured side, and the compact layer was placed against the lateral side. The results showed that the transplantation of neural stem cells in a double-layer collagen membrane with unequal pore sizes promoted the differentiation of neural stem cells, attenuated the pathological lesion, and signiifcantly improved the motor function of the rats with incomplete spinal cord injuries. These experimental ifndings suggest that the transplantation of neural stem cells in a double-lay-er collagen membrane with unequal pore sizes is an effective therapeutic strategy to repair an injured spinal cord.展开更多
Hepatitis C virus (HCV) is a major health problem that leads to chronic hepatitis, cirrhosis and hepatocellular carcinoma, being the most frequent indication for liver transplantation in several countries. Unfortunate...Hepatitis C virus (HCV) is a major health problem that leads to chronic hepatitis, cirrhosis and hepatocellular carcinoma, being the most frequent indication for liver transplantation in several countries. Unfortunately, HCV re-infects the liver graft almost invariably following reperfusion, with an accelerated history of recurrence, leading to 10%-30% of patients progressing to cirrhosis within 5 years of transplantation. In this sense, some groups have even advocated for not retransplanting this patients, as lower patient and graftoutcomes have been reported. However, the management of HCV recurrence is being optimized and several strategies to reduce post-transplant recurrence could improve outcomes, decrease the rate of re-transplantation and optimize the use of available grafts. Three moments may be the focus of potential actions in order to decrease the impact of viral recurrence: the pretransplant moment, the transplant environment and the post-transplant management. In the pre-transplant setting, it is not well established if reducing the pre transplant viral load affects the risk for HCV progression after transplant. Obviously, antiviral treatment can render the patient HCV RNA negative post transplant but the long-term benefit has not yet been fully established to justify the cost and clinical risk. In the transplant moment, factors as donor age, cold ischemia time, graft steatosis and ischemia/reperfusion injury may lead to a higher and more aggressive viral recurrence. After the transplant, discussion about immunosuppression and the moment to start the treatment (prophylactic, pre-emptive or once-confirmed) together with new antiviral drugs are of interest. This review aims to help clinicians have a global overview of posttransplant HCV recurrence and strategies to reduce its impact on our patients.展开更多
Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell ...Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1).展开更多
Following spinal cord injury, astrocyte proliferation and scar formation are the main factors inhibiting the regeneration and growth of spinal cord axons. Recombinant decorin suppresses inflammatory reactions, inhibit...Following spinal cord injury, astrocyte proliferation and scar formation are the main factors inhibiting the regeneration and growth of spinal cord axons. Recombinant decorin suppresses inflammatory reactions, inhibits glial scar formation, and promotes axonal growth. Rat models of T8 spinal cord contusion were created with the NYU impactor and these models were subjected to combined transplantation of bone morphogenetic protein-4-induced glial-restricted precursor-derived astro- cytes and human recombinant decorin transplantation. At 28 days after spinal cord contusion, dou- ble-immunofluorescent histochemistry revealed that combined transplantation inhibited the early in- flammatory response in injured rats. Furthermore, brain-derived neurotrophic factor, which was se- creted by transplanted cells, protected injured axons. The combined transplantation promoted ax- onal regeneration and growth of injured motor and sensory neurons by inhibiting astrocyte prolif- eration and glial scar formation, with astrocytes forming a linear arrangement in the contused spinal cord, thus providing axonal regeneration channels.展开更多
Due to blood transfusions,thalassemics are often infected with either hepatitis C virus(HCV)or hepatitis B virus and often have hemochromatosis.Hepatocellular carcinoma(HCC)has emerged in thalassemics only recently as...Due to blood transfusions,thalassemics are often infected with either hepatitis C virus(HCV)or hepatitis B virus and often have hemochromatosis.Hepatocellular carcinoma(HCC)has emerged in thalassemics only recently as a result of the improvement in thalassemia outcomes.In fact,a prospective study estimated an HCC incidence inβ-thalassemia of about 2%.Although data are scanty,HCC screening in thalassemics with risk factors for HCC should be carried out.HCV treatments have some efficacy in HCV infected thalassemics despite partial contraindication to ribavirin and iron overload.However,there are no data on how HCV treatment translates into HCC prevention.Preliminary data suggest that HCC treatment in thalassemics should generally have the same outcomes as in nonthalassemics.Although coexistence of severe comorbidities makes liver transplantation challenging,this therapeutic possibility should not be precluded for well selected HCCβ-thalassemia patients.In fact,2 transfusion dependent adult HCCβ-thalassemia patients have recently undergone successful liver transplantation with a good outcome.In conclusion,HCC seems to be a developing issue in thalassemia and HCC screening should be carried out.HCC treatment,including liver transplantation,can be performed in selected patients. A multidisciplinary effort is needed for management.展开更多
Background and Aims: To evaluate the effect of intrapar-enchymal transplantation of mesenchymal bone marrow-derived stem cells (BMSCs) in patients with hepatitis C virus (HCV)-related liver cirrhosis (LC). Methods: Mo...Background and Aims: To evaluate the effect of intrapar-enchymal transplantation of mesenchymal bone marrow-derived stem cells (BMSCs) in patients with hepatitis C virus (HCV)-related liver cirrhosis (LC). Methods: Mononuclear cells were isolated from patient bone marrow and were passaged several times in vitro in order to reach the required volume. Attributes of the BMSCs were evaluated by the presence of the surface markers CD105+, CD90+, and CD73+. Cells from each passage were evaluated for sterility, and they were transplanted intraparenchymally into liver tissue. Clinical and laboratory data were evaluated and morphological studies of liver biopsy were performed prior to and 6 months after transplantation. Results: On clinical evaluation, the general state of these patients was improved at 1 month following transplantation of BMSCs. At 1 and 6 months post-transplantation, jaundice was absent in four (67%) patients. After 6 months, functional hepatic indices were improved, i.e. decrease of ALT and AST activity and bilirubin level. However, these decreases were not statistically different (P>0.05). Expression of CD34 and α-SMA in liver biopsy samples were decreased at 6 months after transplanta-tion, consistent with structural improvements in mitochondria and nuclear compartments. Conclusions: Intraparenchymal transplantation of autologous BMSCs improved the functional condition of the liver, stimulated reparative processes in hepatocytes, and decreased extracellular matrix protein (EMP) count in hepatic tissues of patients with LC. It was well tolerated and was not associated with any complications both during and after BMSC transplantation.展开更多
文摘A novel double-layer collagen membrane with unequal pore sizes in each layer was designed and tested in this study. The inner, loose layer has about 100-μm-diameter pores, while the outer, compact layer has about 10-μm-diameter pores. In a rat model of incomplete spinal cord injury, a large number of neural stem cells were seeded into the loose layer, which was then adhered to the injured side, and the compact layer was placed against the lateral side. The results showed that the transplantation of neural stem cells in a double-layer collagen membrane with unequal pore sizes promoted the differentiation of neural stem cells, attenuated the pathological lesion, and signiifcantly improved the motor function of the rats with incomplete spinal cord injuries. These experimental ifndings suggest that the transplantation of neural stem cells in a double-lay-er collagen membrane with unequal pore sizes is an effective therapeutic strategy to repair an injured spinal cord.
基金Supported by The contribution of Ruben Ciria has been possible thanks to the support of a scholarship from the Sociedad Espa ola de Trasplante Hepático (SETH-2009)
文摘Hepatitis C virus (HCV) is a major health problem that leads to chronic hepatitis, cirrhosis and hepatocellular carcinoma, being the most frequent indication for liver transplantation in several countries. Unfortunately, HCV re-infects the liver graft almost invariably following reperfusion, with an accelerated history of recurrence, leading to 10%-30% of patients progressing to cirrhosis within 5 years of transplantation. In this sense, some groups have even advocated for not retransplanting this patients, as lower patient and graftoutcomes have been reported. However, the management of HCV recurrence is being optimized and several strategies to reduce post-transplant recurrence could improve outcomes, decrease the rate of re-transplantation and optimize the use of available grafts. Three moments may be the focus of potential actions in order to decrease the impact of viral recurrence: the pretransplant moment, the transplant environment and the post-transplant management. In the pre-transplant setting, it is not well established if reducing the pre transplant viral load affects the risk for HCV progression after transplant. Obviously, antiviral treatment can render the patient HCV RNA negative post transplant but the long-term benefit has not yet been fully established to justify the cost and clinical risk. In the transplant moment, factors as donor age, cold ischemia time, graft steatosis and ischemia/reperfusion injury may lead to a higher and more aggressive viral recurrence. After the transplant, discussion about immunosuppression and the moment to start the treatment (prophylactic, pre-emptive or once-confirmed) together with new antiviral drugs are of interest. This review aims to help clinicians have a global overview of posttransplant HCV recurrence and strategies to reduce its impact on our patients.
基金This work was supported by the National Natural Science Foundation of China(No.39870661). Phone: (0086-451)-3641309 Fax: (0086-451)-3641253
文摘Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1).
基金supported by funding from the Ministry of Finance People’s Republic of ChinaChina Rehabilitation Research Center Research Program grants, No. 2008-2,2008-3, 2008-4, 2008-5
文摘Following spinal cord injury, astrocyte proliferation and scar formation are the main factors inhibiting the regeneration and growth of spinal cord axons. Recombinant decorin suppresses inflammatory reactions, inhibits glial scar formation, and promotes axonal growth. Rat models of T8 spinal cord contusion were created with the NYU impactor and these models were subjected to combined transplantation of bone morphogenetic protein-4-induced glial-restricted precursor-derived astro- cytes and human recombinant decorin transplantation. At 28 days after spinal cord contusion, dou- ble-immunofluorescent histochemistry revealed that combined transplantation inhibited the early in- flammatory response in injured rats. Furthermore, brain-derived neurotrophic factor, which was se- creted by transplanted cells, protected injured axons. The combined transplantation promoted ax- onal regeneration and growth of injured motor and sensory neurons by inhibiting astrocyte prolif- eration and glial scar formation, with astrocytes forming a linear arrangement in the contused spinal cord, thus providing axonal regeneration channels.
文摘Due to blood transfusions,thalassemics are often infected with either hepatitis C virus(HCV)or hepatitis B virus and often have hemochromatosis.Hepatocellular carcinoma(HCC)has emerged in thalassemics only recently as a result of the improvement in thalassemia outcomes.In fact,a prospective study estimated an HCC incidence inβ-thalassemia of about 2%.Although data are scanty,HCC screening in thalassemics with risk factors for HCC should be carried out.HCV treatments have some efficacy in HCV infected thalassemics despite partial contraindication to ribavirin and iron overload.However,there are no data on how HCV treatment translates into HCC prevention.Preliminary data suggest that HCC treatment in thalassemics should generally have the same outcomes as in nonthalassemics.Although coexistence of severe comorbidities makes liver transplantation challenging,this therapeutic possibility should not be precluded for well selected HCCβ-thalassemia patients.In fact,2 transfusion dependent adult HCCβ-thalassemia patients have recently undergone successful liver transplantation with a good outcome.In conclusion,HCC seems to be a developing issue in thalassemia and HCC screening should be carried out.HCC treatment,including liver transplantation,can be performed in selected patients. A multidisciplinary effort is needed for management.
文摘Background and Aims: To evaluate the effect of intrapar-enchymal transplantation of mesenchymal bone marrow-derived stem cells (BMSCs) in patients with hepatitis C virus (HCV)-related liver cirrhosis (LC). Methods: Mononuclear cells were isolated from patient bone marrow and were passaged several times in vitro in order to reach the required volume. Attributes of the BMSCs were evaluated by the presence of the surface markers CD105+, CD90+, and CD73+. Cells from each passage were evaluated for sterility, and they were transplanted intraparenchymally into liver tissue. Clinical and laboratory data were evaluated and morphological studies of liver biopsy were performed prior to and 6 months after transplantation. Results: On clinical evaluation, the general state of these patients was improved at 1 month following transplantation of BMSCs. At 1 and 6 months post-transplantation, jaundice was absent in four (67%) patients. After 6 months, functional hepatic indices were improved, i.e. decrease of ALT and AST activity and bilirubin level. However, these decreases were not statistically different (P>0.05). Expression of CD34 and α-SMA in liver biopsy samples were decreased at 6 months after transplanta-tion, consistent with structural improvements in mitochondria and nuclear compartments. Conclusions: Intraparenchymal transplantation of autologous BMSCs improved the functional condition of the liver, stimulated reparative processes in hepatocytes, and decreased extracellular matrix protein (EMP) count in hepatic tissues of patients with LC. It was well tolerated and was not associated with any complications both during and after BMSC transplantation.
