The development of the CNS in vertebrate embryos involves the generation of different sub-types of neurons and glia in a complex but highly-ordered spatio-temporal manner. Zebrafish are commonly used for exploring the...The development of the CNS in vertebrate embryos involves the generation of different sub-types of neurons and glia in a complex but highly-ordered spatio-temporal manner. Zebrafish are commonly used for exploring the development, plasticity and regeneration of the CNS, and the recent development of reliable protocols for isolating and culturing neural stem/progenitor cells(NSCs/NPCs) from the brain of adult fish now enables the exploration of mechanisms underlying the induction/specification/differentiation of these cells. Here, we refined a protocol to generate proliferating and differentiating neurospheres from the entire brain of adult zebrafish. We demonstrated via RT-qPCR that some isoforms of ip3 r, ryr and stim are upregulated/downregulated significantly in differentiating neurospheres, and via immunolabelling that 1,4,5-inositol trisphosphate receptor(IP3 R) type-1 and ryanodine receptor(RyR) type-2 are differentially expressed in cells with neuron-or radial glial-like properties. Furthermore, ATP but not caffeine(IP3 R and RyR agonists, respectively), induced the generation of Ca^(2+) transients in cells exhibiting neuron-or glial-like morphology. These results indicate the differential expression of components of the Ca^(2+) -signaling toolkit in proliferating and differentiating cells. Thus, given the complexity of the intact vertebrate brain, neurospheres might be a useful system for exploring neurodegenerative disease diagnosis protocols and drug development using Ca^(2+) signaling as a read-out.展开更多
Scoring the technologies in competition for the NRG Canada’s Oil Sands Innovation Alliance Carbon XPRIZE required an economic evaluation to estimate the value created through the conversion of CO_(2) emissions into p...Scoring the technologies in competition for the NRG Canada’s Oil Sands Innovation Alliance Carbon XPRIZE required an economic evaluation to estimate the value created through the conversion of CO_(2) emissions into products.Across all of the Teams participating in the competition,58 different materials were consumed and produced.Standardized prices and market sizes needed to be established for each of these materials to ensure a consistent evaluation across all Teams.The Standards Data Set(SDS)was created as a standardized database of economic data used in the competition.The rationale for the SDS project and the methodology for researching each material is described.Ultimately,credible material definitions using the SDS methodology were created for all materials,and some research and methodological customization were required for materials that did not have credible,publicly available market data.The methodologies for establishing credible values and market sizes for concrete,concrete admixtures and syngas are highlighted as examples of materials whose value and markets are not easily defined.展开更多
Aim:Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) for chronic hepatitis B (CHB) can be associated with reappearance of hepatitis B surface antigen (HBsAg). The current study determined ...Aim:Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) for chronic hepatitis B (CHB) can be associated with reappearance of hepatitis B surface antigen (HBsAg). The current study determined the significance of HBsAg qualitatively and quantitatively using a highly sensitive assay in recurrent HCC after transplantation. Methods:Consecutive patients with HBV-related HCC with LT were included. Oral nucleos(t)ide analogues without hepatitis B immune globulin were used as hepatitis B virus (HBV) prophylaxis. Quantitative HBsAg levels were performed at time of transplant, at 1 month, 3 and 6 months post transplant using a highly sensitive (hs)-HBsAg assay. Results:One hundred and fourteen patients were included, with a median follow-up of 80 months, with 24 cases of HCC recurrence, and a cumulative rate of 20.7% at 5 years. There was significant correlation between time of tumor recurrence and time of HBsAg reappearance (r = 0.551,P = 0.027). Early HCC recurrence was associated with higher median level of hs-HBsAg at the time of transplant (72.85vs. 69.70 IU/mL,P = 0.018). Using a hs-HBsAg cut-off level of 0.0005 IU/mL, patients with levels above this threshold at 3 and 6 months were associated with higher rate of early HCC recurrence (28.6%vs. 3.0% and 26.9%vs. 2.9% respectively, bothP =0.0006). There was no significant difference in HCC recurrence between positive and negative HBsAg using the conventional qualitative HBsAg assay. Conclusion:Serum hs-HBsAg levels of≥ 0.0005 IU/mL at 3 to 6 months after LT is associated with higher rates of early HCC recurrence, and may be useful as an early tumor marker.展开更多
基金supported by the ANR/RGC Joint Research Scheme Award (A-HKUST601/ 13)the HK RGC General Research Fund awards (662113, 16101714, 16100115)Funding from the HKITC (ITCPD/17-9)
文摘The development of the CNS in vertebrate embryos involves the generation of different sub-types of neurons and glia in a complex but highly-ordered spatio-temporal manner. Zebrafish are commonly used for exploring the development, plasticity and regeneration of the CNS, and the recent development of reliable protocols for isolating and culturing neural stem/progenitor cells(NSCs/NPCs) from the brain of adult fish now enables the exploration of mechanisms underlying the induction/specification/differentiation of these cells. Here, we refined a protocol to generate proliferating and differentiating neurospheres from the entire brain of adult zebrafish. We demonstrated via RT-qPCR that some isoforms of ip3 r, ryr and stim are upregulated/downregulated significantly in differentiating neurospheres, and via immunolabelling that 1,4,5-inositol trisphosphate receptor(IP3 R) type-1 and ryanodine receptor(RyR) type-2 are differentially expressed in cells with neuron-or radial glial-like properties. Furthermore, ATP but not caffeine(IP3 R and RyR agonists, respectively), induced the generation of Ca^(2+) transients in cells exhibiting neuron-or glial-like morphology. These results indicate the differential expression of components of the Ca^(2+) -signaling toolkit in proliferating and differentiating cells. Thus, given the complexity of the intact vertebrate brain, neurospheres might be a useful system for exploring neurodegenerative disease diagnosis protocols and drug development using Ca^(2+) signaling as a read-out.
基金Funding for this project was provided by NRG and COSIA(Canada’s Oil Sands Innovation Alliance)through their sponsorship of the NRG COSIA Carbon XPRIZE.
文摘Scoring the technologies in competition for the NRG Canada’s Oil Sands Innovation Alliance Carbon XPRIZE required an economic evaluation to estimate the value created through the conversion of CO_(2) emissions into products.Across all of the Teams participating in the competition,58 different materials were consumed and produced.Standardized prices and market sizes needed to be established for each of these materials to ensure a consistent evaluation across all Teams.The Standards Data Set(SDS)was created as a standardized database of economic data used in the competition.The rationale for the SDS project and the methodology for researching each material is described.Ultimately,credible material definitions using the SDS methodology were created for all materials,and some research and methodological customization were required for materials that did not have credible,publicly available market data.The methodologies for establishing credible values and market sizes for concrete,concrete admixtures and syngas are highlighted as examples of materials whose value and markets are not easily defined.
文摘Aim:Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) for chronic hepatitis B (CHB) can be associated with reappearance of hepatitis B surface antigen (HBsAg). The current study determined the significance of HBsAg qualitatively and quantitatively using a highly sensitive assay in recurrent HCC after transplantation. Methods:Consecutive patients with HBV-related HCC with LT were included. Oral nucleos(t)ide analogues without hepatitis B immune globulin were used as hepatitis B virus (HBV) prophylaxis. Quantitative HBsAg levels were performed at time of transplant, at 1 month, 3 and 6 months post transplant using a highly sensitive (hs)-HBsAg assay. Results:One hundred and fourteen patients were included, with a median follow-up of 80 months, with 24 cases of HCC recurrence, and a cumulative rate of 20.7% at 5 years. There was significant correlation between time of tumor recurrence and time of HBsAg reappearance (r = 0.551,P = 0.027). Early HCC recurrence was associated with higher median level of hs-HBsAg at the time of transplant (72.85vs. 69.70 IU/mL,P = 0.018). Using a hs-HBsAg cut-off level of 0.0005 IU/mL, patients with levels above this threshold at 3 and 6 months were associated with higher rate of early HCC recurrence (28.6%vs. 3.0% and 26.9%vs. 2.9% respectively, bothP =0.0006). There was no significant difference in HCC recurrence between positive and negative HBsAg using the conventional qualitative HBsAg assay. Conclusion:Serum hs-HBsAg levels of≥ 0.0005 IU/mL at 3 to 6 months after LT is associated with higher rates of early HCC recurrence, and may be useful as an early tumor marker.