Self-renewal and differentiation capabilities are variable between human embryonic stem cell lines I3, I6 and BG01V

<p>Abstract</p> <p>Background</p> <p>A unique and essential property of embryonic stem cells is the ability to self-renew and differentiate into multiple cell lineages. However, the possible differences in proliferation and differentiation capabilities among independently-derived human embryonic stem cells (hESCs) are not well known because of insufficient characterization. To address this question, a side-by-side comparison of 1) the ability to maintain an undifferentiated state and to self-renew under standard conditions; 2) the ability to spontaneously differentiate into three primary embryonic germ lineages in differentiating embryoid bodies; and 3) the responses to directed neural differentiation was made between three NIH registered hES cell lines I3 (TE03), I6 (TE06) and BG01V. Lines I3 and I6 possess normal XX and a normal XY karyotype while BG01V is a variant cell line with an abnormal karyotype derived from the karyotypically normal cell line BG01.</p> <p>Results</p> <p>Using immunocytochemistry, flow cytometry, qRT-PCR and MPSS, we found that all three cell lines actively proliferated and expressed similar "stemness" markers including transcription factors POU5F1/Oct3/4 and NANOG, glycolipids SSEA4 and TRA-1-81, and alkaline phosphatase activity. All cell lines differentiated into three embryonic germ lineages in embryoid bodies and into neural cell lineages when cultured in neural differentiation medium. However, a profound variation in colony morphology, growth rate, BrdU incorporation, and relative abundance of gene expression in undifferentiated and differentiated states of the cell lines was observed. Undifferentiated I3 cells grew significantly slower but their differentiation potential was greater than I6 and BG01V. Under the same neural differentiation-promoting conditions, the ability of each cell line to differentiate into neural progenitors varied.</p> <p>Conclusion</p> <p>Our comparative analysis provides further evidence for similarities and differences between three hESC lines in self-renewal, and spontaneous and directed differentiation. These differences may be associated with inherited variation in the sex, stage, quality and genetic background of embryos used for hESC line derivation, and/or changes acquired during passaging in culture.</p

N-Acetylcysteine prevents congenital heart defects induced by pregestational diabetes

Background: Pregestational diabetes is a major risk factor of congenital heart defects (CHDs). Glutathione is depleted and reactive oxygen species (ROS) production is elevated in diabetes. In the present study, we aimed to examine whether treatment with N-acetylcysteine (NAC), which increases glutathione synthesis and inhibits ROS production, prevents CHDs induced by pregestational diabetes.Methods: Female mice were treated with streptozotocin (STZ) to induce pregestational diabetes prior to breeding with normal males to produce offspring. Some diabetic mice were treated with N-acetylcysteine (NAC) in drinking water from E0.5 to the end of gestation or harvesting of the embryos. CHDs were identified by histology. ROS levels, cell proliferation and gene expression in the fetal heart were analyzed.Results: Our data show that pregestational diabetes resulted in CHDs in 58% of the offspring, including ventricular septal defect (VSD), atrial septal defect (ASD), atrioventricular septal defects (AVSD), transposition of great arteries (TGA), double outlet right ventricle (DORV) and tetralogy of Fallot (TOF). Treatment with NAC in drinking water in pregestational diabetic mice completely eliminated the incidence of AVSD, TGA, TOF and significantly diminished the incidence of ASD and VSD. Furthermore, pregestational diabetes increased ROS, impaired cell proliferation, and altered Gata4, Gata5 and Vegf-a expression in the fetal heart of diabetic offspring, which were all prevented by NAC treatment.Conclusions: Treatment with NAC increases GSH levels, decreases ROS levels in the fetal heart and prevents the development of CHDs in the offspring of pregestational diabetes. Our study suggests that NAC may have therapeutic potential in the prevention of CHDs induced by pregestational diabetes. © 2014 Moazzen et al.; licensee BioMed Central Ltd

The Time Course of the Influence of Valence and Arousal on the Implicit Processing of Affective Pictures

In the current study, we investigated the time course of the implicit processing of affective pictures with an orthogonal design of valence (negative vs. positive) by arousal (low vs. high). Previous studies with explicit tasks suggested that valence mainly modulates early event-related potential (ERP) components, whereas arousal mainly modulates late components. However, in this study with an implicit task, we observed significant interactions between valence and arousal at both early and late stages over both parietal and frontal sites, which were reflected by three different ERP components: P2a (100–200 ms), N2 (200–300 ms), and P3 (300–400 ms). Furthermore, there was also a significant main effect of arousal on P2b (200–300 ms) over parieto-occipital sites. Our results suggest that valence and arousal effects on implicit affective processing are more complicated than previous ERP studies with explicit tasks have revealed

The current situation and the driving mechanism of energy consumption in China in the context of the peak of carbon emissions in 2030

The Chinese economy is actively switching to the use of gas in the energy sector and in the residential sector. At the same time, with the scale of the Chinese economy, coal will be in demand for a long time, since technological and economic reasons make it difficult to quickly abandon this raw material in favor of less carbon-intensive types of energy resources. China is the world's largest consumer and importer of energy resources, whose structure has long relied on the use of coal for electricity generation. Stable economic growth and the development of industrial production in the country have caused serious environmental problems associated with the emission of carbon dioxide into the atmosphere. The article discusses the main aspects of the current situation of energy consumption in China in the context of the peak of carbon emissions in 2030. The author conducted a meta-regression analysis, the results are shown in Table 1. The framework of China's climate policy is considered in detail, as well as how China will reach a peak in carbon emissions by 2030. The regression results show that all variables are significant for peak CO2 emissions, with the exception of the variable rate of decrease in the intensity of carbon emissions at the peak of carbon emissions (peakCEI), significant for the time of peak carbon emissions, with the exception of the variable paper type (PTY), impact factor (IF), classification of the share of coal at the peak of carbon emissions (yblcal) and the share of coal at the peak of carbon emissions (pnf). According to the author, in the future China should conduct in-depth research in these areas, including studying the optimal path to the carbon peak based on the cost-benefit theory, improve methods of accounting for greenhouse gas inventories, actively promote the progress of clean energy technologies, improving the quality of economic development, etc

Investigation of Vegetation Changes in Different Mining Areas in Liaoning Province, China, Using Multisource Remote Sensing Data

Mining can provide necessary mineral resources for humans. However, mining activities may cause damage to the surrounding ecology and environment. Vegetation change analysis is a key tool for evaluating damage to ecology and the environment. Liaoning is one of the major mining provinces in China, with rich mineral resources and long-term, high-intensity mining activities. Taking Liaoning Province as an example, vegetation change in six mining areas was investigated using multisource remote sensing data to evaluate ecological and environmental changes. Based on MODIS NDVI series data from 2000 to 2019, change trends of vegetation were evaluated using linear regression. According to the results, there are large highly degraded vegetation areas in the Anshan, Benxi, and Yingkou mining areas, which indicates that mining activities have seriously damaged the vegetation in these areas. In contrast, there are considerable areas with improved vegetation in the Anshan, Fushun, and Fuxin mining areas, which indicates that ecological reclamation has played a positive role in these areas. Based on Sentinel-2A data, leaf chlorophyll content was inferred by using the vegetation index MERIS Terrestrial Chlorophyll Index (MTCI) after measurement of leaf spectra and chlorophyll content were carried out on the ground to validate the performance of MTCI. According to the results, the leaf chlorophyll content in the mines is generally lower than in adjacent areas in these mining areas with individual differences. In the Yingkou mining area, the chlorophyll content in adjacent areas is close to the magnesite mines, which means the spillover effect of environmental pollution in mines should be considerable. In the Anshan, Benxi, and Diaobingshan mining areas, the environmental stress on adjacent areas is slight. All in all, iron and magnesite open-pit mines should be monitored closely for vegetation destruction and stress due to the high intensity of mining activities and serious pollution. In contrast, the disturbance to vegetation is limited in resource-exhausted open-pit coal mines and underground coal mines. It is suggested that land reclamation should be enhanced to improve the vegetation in active open-pit mining areas, such as the Anshan, Benxi, and Yingkou mining areas. Additionally, environmental protection measures should be enhanced to relieve vegetation stress in the Yingkou mining area