89 research outputs found
Cardiac-derived CTRP9 protects against myocardial ischemia/reperfusion injury via calreticulin-dependent inhibition of apoptosis.
Cardiokines play an essential role in maintaining normal cardiac functions and responding to acute myocardial injury. Studies have demonstrated the heart itself is a significant source of C1q/TNF-related protein 9 (CTRP9). However, the biological role of cardiac-derived CTRP9 remains unclear. We hypothesize cardiac-derived CTRP9 responds to acute myocardial ischemia/reperfusion (MI/R) injury as a cardiokine. We explored the role of cardiac-derived CTRP9 in MI/R injury via genetic manipulation and a CTRP9-knockout (CTRP9-KO) animal model. Inhibition of cardiac CTRP9 exacerbated, whereas its overexpression ameliorated, left ventricular dysfunction and myocardial apoptosis. Endothelial CTRP9 expression was unchanged while cardiomyocyte CTRP9 levels decreased after simulated ischemia/`reperfusion (SI/R) in vitro. Cardiomyocyte CTRP9 overexpression inhibited SI/R-induced apoptosis, an effect abrogated by CTRP9 antibody. Mechanistically, cardiac-derived CTRP9 activated anti-apoptotic signaling pathways and inhibited endoplasmic reticulum (ER) stress-related apoptosis in MI/R injury. Notably, CTRP9 interacted with the ER molecular chaperone calreticulin (CRT) located on the cell surface and in the cytoplasm of cardiomyocytes. The CTRP9-CRT interaction activated the protein kinase A-cAMP response element binding protein (PKA-CREB) signaling pathway, blocked by functional neutralization of the autocrine CTRP9. Inhibition of either CRT or PKA blunted cardiac-derived CTRP9\u27s anti-apoptotic actions against MI/R injury. We further confirmed these findings in CTRP9-KO rats. Together, these results demonstrate that autocrine CTRP9 of cardiomyocyte origin protects against MI/R injury via CRT association, activation of the PKA-CREB pathway, ultimately inhibiting cardiomyocyte apoptosis
EST analysis of gene expression in the tentacle of Cyanea capillata
AbstractJellyfish, Cyanea capillata, has an important position in head patterning and ion channel evolution, in addition to containing a rich source of toxins. In the present study, 2153 expressed sequence tags (ESTs) from the tentacle cDNA library of C. capillata were analyzed. The initial ESTs consisted of 198 clusters and 818 singletons, which revealed approximately 1016 unique genes in the data set. Among these sequences, we identified several genes related to head and foot patterning, voltage-dependent anion channel gene and genes related to biological activities of venom. Five kinds of proteinase inhibitor genes were found in jellyfish for the first time, and some of them were highly expressed with unknown functions
Soft Substrates Promote Homogeneous Self-Renewal of Embryonic Stem Cells via Downregulating Cell-Matrix Tractions
Maintaining undifferentiated mouse embryonic stem cell (mESC) culture has been a major challenge as mESCs cultured in Leukemia Inhibitory Factor (LIF) conditions exhibit spontaneous differentiation, fluctuating expression of pluripotency genes, and genes of specialized cells. Here we show that, in sharp contrast to the mESCs seeded on the conventional rigid substrates, the mESCs cultured on the soft substrates that match the intrinsic stiffness of the mESCs and in the absence of exogenous LIF for 5 days, surprisingly still generated homogeneous undifferentiated colonies, maintained high levels of Oct3/4, Nanog, and Alkaline Phosphatase (AP) activities, and formed embryoid bodies and teratomas efficiently. A different line of mESCs, cultured on the soft substrates without exogenous LIF, maintained the capacity of generating homogeneous undifferentiated colonies with relatively high levels of Oct3/4 and AP activities, up to at least 15 passages, suggesting that this soft substrate approach applies to long term culture of different mESC lines. mESC colonies on these soft substrates without LIF generated low cell-matrix tractions and low stiffness. Both tractions and stiffness of the colonies increased with substrate stiffness, accompanied by downregulation of Oct3/4 expression. Our findings demonstrate that mESC self-renewal and pluripotency can be maintained homogeneously on soft substrates via the biophysical mechanism of facilitating generation of low cell-matrix tractions
Nitrogen Doped Macroporous Carbon as Electrode Materials for High Capacity of Supercapacitor
Nitrogen doped carbon materials as electrodes of supercapacitors have attracted abundant attention. Herein, we demonstrated a method to synthesize N-doped macroporous carbon materials (NMC) with continuous channels and large size pores carbonized from polyaniline using multiporous silica beads as sacrificial templates to act as electrode materials in supercapacitors. By the nice carbonized process, i.e., pre-carbonization at 400 °C and then pyrolysis at 700/800/900/1000 °C, NMC replicas with high BET specific surface areas exhibit excellent stability and recyclability as well as superb capacitance behavior (~413 F ⋅ g−1) in alkaline electrolyte. This research may provide a method to synthesize macroporous materials with continuous channels and hierarchical pores to enhance the infiltration and mass transfer not only used as electrode, but also as catalyst somewhere micro- or mesopores do not work well
Transcriptome Analysis Reveals the Molecular Mechanisms Underlying Growth Superiority in a Novel <i>Gymnocypris</i> Hybrid, <i>Gymnocypris przewalskii</i> ♀ × <i>Gymnocypris eckloni</i> ♂
Artificial hybrid breeding can optimize parental traits to cultivate excellent hybrids with enhanced economic value. In this study, we investigated the growth performance and transcriptomes of Gymnocypris przewalskii (♀) and Gymnocypris eckloni (♂) and their F1 hybrid fishes. Hatched individuals of G. przewalskii (GP) and G. eckloni (GE) of the same size and their F1 hybrids (GH) were separately cultured for eight months in three cement tanks (n = 3). The growth indexes were measured, which showed that the growth rate of the groups was GE > GH > GP, while the survival rate was GH > GE > GP. The RNA-Seq data analysis of the muscles from the three Gymnocypris fish strains revealed that gene transcription has a significant impact on F1 hybrid fish and its parents. The differentially expressed genes (DEGs) in GH show less differences with GP, but more with GE. qRT-PCR was used to confirm the expression profiles of the chosen DEGs, and the results showed positive correlations with the RNA-seq data. KEGG enrichment results indicated that the DEGs were related to a variety of molecular functions, such as glycolysis/gluconeogenesis, arachidonic acid formation, citrate cycle, and the MAPK, PI3K-Akt, or mTOR signal pathways. Subsequent analysis indicated that there may be a significant correlation between the differential expression of IGF2 and a difference in the growth of GE and GP
Heteroatom-Doped Carbon Nanostructures Derived from Conjugated Polymers for Energy Applications
Heteroatom-doped carbon materials have been one of the most remarkable families of materials with promising applications in fuel cells, supercapacitors, and batteries. Among them, conjugated polymer (CP)-derived heteroatom-doped carbon materials exhibit remarkable electrochemical performances because the heteroatoms can be preserved at a relatively high content and keep stable under harsh working conditions. In this review, we summarized recent advances in the rational design and various applications of CP-derived heteroatom-doped carbon materials, including polyaniline (PANI), polypyrrole (PPy), and their ramification-derived carbons, as well as transition metal-carbon nanocomposites. The key point of considering CP-derived heteroatom-doped carbon materials as important candidates of electrode materials is that CPs contain only nonmetallic elements and some key heteroatoms in their backbones which provide great chances for the synthesis of metal-free heteroatom-doped carbon nanostructures. The presented examples in this review will provide new insights in designing and optimizing heteroatom-doped carbon materials for the development of anode and cathode materials for electrochemical device applications
Function Evaluation and Coordination Analysis of Production–Living–Ecological Space Based on the Perspective of Type–Intensity–Connection: A Case Study of Suzhou, China
The function evaluation and coordination analysis of production–living–ecological space is of great significance for guiding the high-quality development of territorial space. Considering the complexity of territorial space, this study constructed the evaluation index system of production–living–ecological spatial functions based on the perspective of “type–intensity–connection” and used multisource data to conduct empirical analysis in Suzhou, China, as an example. The results show that there were significant regional and urban-rural differences in the production–living–ecological comprehensive functional level of Suzhou, and it presents a composite spatial structure characterized by core-agglomeration, multipoint-dispersion, and centre-periphery. Among them, the functions of production and living spaces were concentrated with high values and have similar spatial structure, while the function of ecological space has low values and is distributed in contiguous areas around the production and living spaces. Overall, the coordination relationships of living–production space, ecological–living space and ecological–production space show significant positive, negative and negative correlations, respectively. However, in local space, the coordination relationship was composed of two types of leading relationships. This mainly reflects the great coordination between production space and living space, while the coordination between ecological space and other space is poor and needs to be improved. Therefore, it’s necessary to continuously improve the adequacy and balance of the functional quality of production–living–ecological space and increase organic connectivity and benign integration
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