New Approaches in the Differentiation of Human Embryonic Stem Cells and Induced Pluripotent Stem Cells toward Hepatocytes

Orthotropic liver transplantation is the only established treatment for end-stage liver diseases. Utilization of hepatocyte transplantation and bio-artificial liver devices as alternative therapeutic approaches requires an unlimited source of hepatocytes. Stem cells, especially embryonic stem cells, possessing the ability to produce functional hepatocytes for clinical applications and drug development, may provide the answer to this problem. New discoveries in the mechanisms of liver development and the emergence of induced pluripotent stem cells in 2006 have provided novel insights into hepatocyte differentiation and the use of stem cells for therapeutic applications. This review is aimed towards providing scientists and physicians with the latest advancements in this rapidly progressing field

Construction and Promotion Path of Public Library Service Capacity in the Smart Library Era

[Purpose/Significance] The transformation of public libraries into smart libraries depends on the continuous improvement of their own service capacity. With a growing interest in the construction of smart libraries, this paper takes public library service capacity as the research object and explores the construction and promotion path of public library service capacity, offering a guidance for public libraries' transformation into smart libraries. [Method/Process] Following the research ideas from the current situation to the future development, this paper first studied the three-stage evolution of public library service development through literature review, and re-examines the concept, characteristics and requirements of public library service capacity in the era of smart libraries. Then, based on the existing standard system, and considering the new demands in the smart library era, we explored the service capacity system of public libraries with an analysis on the constituent elements and influencing factors. [Results/Conclusions] The transformation of public libraries into smart libraries is a long and gradual process, and the construction of public library service capacity will also be a dynamic process of continuous in-depth development. Therefore, public libraries are suggested to promote their service capacity step by step based on their factor structure. The construction of public library service capacity in the era of smart libraries includes five dimensions: resource capacity, talent capacity, cultural capacity, management capacity and environmental ability. Therefore, we suggest that public libraries improve their service capacity through five paths, including (1) to build a resource system based on smart service through integration and reorganization; (2) to cultivate the ability of librarians based on smart service through enabling librarians' growth; (3) to build an organizational culture based on smart service through reshaping the concept; (4) to innovate the management model based on smart service evaluation and assessment; (5) to create a cooperation environment based on smart services through alliance collaboration, so as to promote the development of public libraries. This research provides specific methodological guidance for the construction of public library service capacity. However, due to the limitation of time, the integrity of the service capacity indicator system in this research still needs to be verified. We will continue to conduct the in-depth research based on the theory and evaluation system of library service capacity, and refine the indicators, so as to provide theoretical basis and reference for public libraries to establish their smart library strategic planning based on service capacity evaluation

Family-based analysis of -675 4G/5G polymorphism in the PAI-1 gene of polycystic ovary syndrome in Chinese population

Previous studies have shown that 4G/5G polymorphism in promoter region of plasminogen activator inhibitor-1 (PAI-1) gene can affect insulin sensitivity by elevating the level and activity of plasma PAI-1. In order to elucidate the relationship between the polymorphism of PAI-1 gene and polycystic ovary syndrome (PCOS), we used transmission disequilibrium test (TDT) to study the family of PCOS. Eight hundred and fifty-five participants consisting of 285 trios (mother, father and offspring with PCOS) were recruited at the Center of Reproductive Medicine, Shandong University from July 2007 to August 2014. 4G/5G polymorphism of PAI-1 gene was genotyped using direct sequencing protocol and TDT was used to analyse the association between PAI-1 gene and PCOS. Though the 5G allele in PAI-1 gene was overtransmitted in families, no statistical significance existed and there was no association between PAI-1 gene and PCOS, indicating that PAI-1 gene was unlikely to play a major role in the aetiology of PCOS in Chinese population.Impact Statement What is already known on this subject? Some studies have shown that 4G/5G polymorphism in promoter region of plasminogen activator inhibitor-1 (PAI-1) gene can affect insulin sensitivity by elevating the level and activity of plasma PAI-1, participating in the formation of insulin resistance (IR). What do the results of this study add? Though the 5G allele in PAI-1 gene was overtransmitted in families, no statistical significance existed and there was no association between PAI-1 gene and polycystic ovary syndrome (PCOS). What are the implications of these findings for clinical practice and/or further research? PAI-1 gene was unlikely to play a major role in the aetiology of PCOS

The differentiation of hepatocyte-like cells from monkey embryonic stem cells.

Embryonic stem cells (ESC) hold great potential for the treatment of liver diseases. Here, we report the differentiation of rhesus macaque ESC along a hepatocyte lineage. The undifferentiated monkey ESC line, ORMES-6, was cultured in an optimal culture condition in an effort to differentiate them into hepatocyte-like cells in vitro. The functional efficacy of the differentiated hepatic cells was evaluated using RT-PCR for the expression of hepatocyte specific genes, and Western blot analysis and immunocytochemistry for hepatic proteins such as alpha-fetoprotein (AFP), albumin and alpha1-antitrypsin (alpha1-AT). Functional assays were performed using the periodic acid schiff (PAS) reaction and ELISA. The final yield of ESC-derived hepatocyte-like cells was measured by flow cytometry for cells that were transduced with a liver-specific lentivirus vector containing the alpha1-AT promoter driving the expression of green fluorescence protein (GFP). The treatment of monkey ESC with an optimal culture condition yielded hepatocyte-like cells that expressed albumin, alpha1-AT, AFP, hepatocyte nuclear factor 3beta, glucose-6-phophatase, and cytochrome P450 genes and proteins as determined by RT-PCR and Western blot analysis. Immunofluorescent staining showed the cells positive for albumin, AFP, and alpha1-AT. PAS staining demonstrated that the differentiated cells showed hepatocyte functional activity. Albumin could be detected in the medium after 20 days of differentiation. Flow cytometry data showed that 6.5 +/- 1.0% of the total differentiated cells were positive for GFP. These results suggest that by using a specific, empirically determined, culture condition, we were able to direct monkey ESC toward a hepatocyte lineage

The differentiation of hepatocyte-like cells from monkey embryonic stem cells.

Embryonic stem cells (ESC) hold great potential for the treatment of liver diseases. Here, we report the differentiation of rhesus macaque ESC along a hepatocyte lineage. The undifferentiated monkey ESC line, ORMES-6, was cultured in an optimal culture condition in an effort to differentiate them into hepatocyte-like cells in vitro. The functional efficacy of the differentiated hepatic cells was evaluated using RT-PCR for the expression of hepatocyte specific genes, and Western blot analysis and immunocytochemistry for hepatic proteins such as alpha-fetoprotein (AFP), albumin and alpha1-antitrypsin (alpha1-AT). Functional assays were performed using the periodic acid schiff (PAS) reaction and ELISA. The final yield of ESC-derived hepatocyte-like cells was measured by flow cytometry for cells that were transduced with a liver-specific lentivirus vector containing the alpha1-AT promoter driving the expression of green fluorescence protein (GFP). The treatment of monkey ESC with an optimal culture condition yielded hepatocyte-like cells that expressed albumin, alpha1-AT, AFP, hepatocyte nuclear factor 3beta, glucose-6-phophatase, and cytochrome P450 genes and proteins as determined by RT-PCR and Western blot analysis. Immunofluorescent staining showed the cells positive for albumin, AFP, and alpha1-AT. PAS staining demonstrated that the differentiated cells showed hepatocyte functional activity. Albumin could be detected in the medium after 20 days of differentiation. Flow cytometry data showed that 6.5 +/- 1.0% of the total differentiated cells were positive for GFP. These results suggest that by using a specific, empirically determined, culture condition, we were able to direct monkey ESC toward a hepatocyte lineage

High level of reactive oxygen species inhibits triacylglycerols accumulation in Chlamydomonas reinhardtii

Many microalgae accumulate large amounts of lipid droplets (LDs) following N deprivation. The triacylglycerols (TAGs) in these LDs can be used as a feedstock to produce biodiesel. To investigate the molecular mechanism underlying LD formation, we used a percoll gradient-based method to enrich for mutants with defects in LD formation and generated an insertional mutagenesis library containing > 11,000 Chlamydomonas reinhardtii transformants. One of the mutants harbored a mutation in a gene encoding a glutathione peroxidase (GPX5) that catalyzes the formation of water from hydrogen peroxide (H2O2) or organic hydroperoxide. The gpx5 mutant had a 35% reduction in the number of LDs and a 50% reduction in TAG content compared with the parental strain CC4348 at 24 h of N deprivation. The full-length of GPX5 or truncate GPX5 without the putative signal peptide or the putative signal peptide of GPX5 fused YFP localized in the cytoplasm, but not in chloroplasts. Complementation with full-length GPX5 rescued the mutant phenotypes, and the expression of GPX5 in a complemented strain L27 was increased 2-3 fold after 24 h of N deprivation. Moreover, the gpx5 mutant showed increased sensitivity to the singlet oxygen (O-1(2)) stress generated by the photosensitizer Rose Bengal (RB). The ROS concentration of the gpx5 was about 1.5 times that of CC4348 during N deprivation. Artificial increasing of ROS concentration in cells abolished the formation of LDs in Chlamydomonas. These data suggest that a high level of ROS attenuates LD formation