Preclinical evaluation of the safety and effectiveness of a new bioartificial cornea.

Cross-linking agents are frequently used to restore corneal properties after decellularization, and it is especially important to select an appropriate method to avoid excessive cross-linking. In addition, how to promote wound healing and how to improve scar formation require further investigation. To ensure the safety and efficacy of animal-derived products, we designed bioartificial corneas (BACs) according to the criteria for Class III medical devices. Our BACs do not require cross-linking agents and increase mechanical strength via self-cross-linking of aldehyde-modified hyaluronic acid (AHA) and carboxymethyl chitosan (CMC) on the surface of decellularized porcine corneas (DPCs). The results showed that the BACs had good biocompatibility and transparency, and the modification enhanced their antibacterial and anti-inflammatory properties in vitro. Preclinical animal studies showed that the BACs can rapidly regenerate the epithelium and restore vision within a month. After 3 months, the BACs were gradually filled with epithelial, stromal, and neuronal cells, and after 6 months, their transparency and histology were almost normal. In addition, side effects such as corneal neovascularization, conjunctival hyperemia, and ciliary body hyperemia rarely occur in vivo. Therefore, these BACs show promise for clinical application for the treatment of infectious corneal ulcers and as a temporary covering for corneal perforations to achieve the more time.

Transcription factor OsNAC055 regulates GA-mediated lignin biosynthesis in rice straw.

Crop straws represent enormous biomass resource that mainly contain secondary cell walls (SCWs) consisting of cellulose, hemicelluloses and lignin. Nevertheless, the regulatory mechanism of SCW biosynthesis still needs to be well understood. In this study, we identified a rice NAC (NAM, ATAF1/2, CUC2) transcription factor OsNAC055 that regulates GA-mediated lignin biosynthesis. As a nucleus-localized transcription factor, OsNAC055 exhibits the transcriptional activation activity. Overexpression of OsNAC055 increases the lignin content in rice straw. Transcriptomic analyses showed that the expression of multiple lignin biosynthetic genes was increased in OsNAC055-overexpressing plants. Further ChIP-qPCR analysis and transient transactivation assays indicated that OsNAC055 directly activates rice lignin biosynthetic genes CINNAMOYL-CoA REDUCTASE 10 (OsCCR10) and CINNAMYL ALCOHOL DEHYDROGENASE 2 (OsCAD2) by binding to their promoters. On the other hand, phytohormone measurement showed that OsNAC055 overexpression significantly increased exogenous GA3 levels in rice plants by regulating GA biosynthetic gene OsGA20ox2. Moreover, yeast two-hybrid and bimolecular fluorescence complement (BiFC) assays indicated that OsNAC055 interacts with SLENDER RICE1 (SLR1), the repressor in GA signaling. More importantly, exogenous GA treatment markedly enhanced the transcription of OsCCR10 and OsCAD2, suggesting the role of GA in lignin biosynthesis. Together, our results provide the evidence that OsNAC055 functions as an essential transcription factor to regulate the GA-mediated lignin biosynthesis, which provides a strategy for manipulating lignin production.

Engineering hiPSC-CM and hiPSC-EC laden 3D nanofibrous splenic hydrogel for improving cardiac function through revascularization and remuscularization in infarcted heart.

Cell therapy has been a promising strategy for cardiac repair after myocardial infarction (MI), but a poor ischemic environment and low cell delivery efficiency remain significant challenges. The spleen serves as a hematopoietic stem cell niche and secretes cardioprotective factors after MI, but it is unclear whether it could be used for human pluripotent stem cell (hiPSC) cultivation and provide a proper microenvironment for cell grafts against the ischemic environment. Herein, we developed a splenic extracellular matrix derived thermoresponsive hydrogel (SpGel). Proteomics analysis indicated that SpGel is enriched with proteins known to modulate the Wnt signaling pathway, cell-substrate adhesion, cardiac muscle contraction and oxidation-reduction processes. In vitro studies demonstrated that hiPSCs could be efficiently induced into endothelial cells (iECs) and cardiomyocytes (iCMs) with enhanced function on SpGel. The cytoprotective effect of SpGel on iECs/iCMs against oxidative stress damage was also proven. Furthermore, in vivo studies revealed that iEC/iCM-laden SpGel improved cardiac function and inhibited cardiac fibrosis of infarcted hearts by improving cell survival, revascularization and remuscularization. In conclusion, we successfully established a novel platform for the efficient generation and delivery of autologous cell grafts, which could be a promising clinical therapeutic strategy for cardiac repair and regeneration after MI.

Integration of the proteome and transcriptome reveals multiple levels of gene regulation in the rice dl2 mutant.

Leaf vascular system differentiation and venation patterns play a key role in transporting nutrients and maintaining the plant shape, which is an important agronomic trait for improving photosynthetic efficiency. However, there is little knowledge about the regulation of leaf vascular specification and development. Here we utilized the rice midribless mutant (dl2) to investigate the molecular changes in transcriptome and proteome profiles during leaf vascular specification and differentiation. Using isobaric tags for relative and absolute quantification (iTRAQ) with digital gene expression (DGE) techniques, a nearly complete catalog of expressed protein and mRNA was acquired. From the catalog, we reliably identified 3172 proteins and 9,865,230 tags mapped to genes, and subsets of 141 proteins and 98 mRNAs, which were differentially expressed between the dl2 mutant and wild type. The correlation analysis between the abundance of differentially expressed mRNA and DEPs (differentially expressed proteins) revealed numerous discordant changes in mRNA/protein pairs and only a modest correlation was observed, indicative of divergent regulation of transcription and translational processes. The DEPs were analyzed for their involvement in biological processes and metabolic pathways. Up- or down- regulation of some key proteins confirmed that the physiological process of vascular differentiation is an active process. These key proteins included those not previously reported to be associated with vascular differentiation processes, and included proteins that are involved in the spliceosome pathway. Together, our results show that the developmental and physiological process of the leaf vascular system is a thoroughly regulated and complicated process and this work has identified potential targets for genetic modification that could be used to regulate the development of the leaf vasculature.

[A study on technology of harvest and process for stem and fruit of Akebia trifoliate].

The harvest and process experiment were carried out on the stem and fruit of Akebia trifoliate. The results showed that the medicinal materials were more excellent as the collecting period postponed, the quality of main stem from three year old was better than those of youngers or first and second branch, such as the index of aridity,the color,the mineral content,the maceration extract content and airflow trait. Stems collected in the Mid-November were observably better than those in the March, May, July and Mid-September. Fruits collected on the first day of September were more excellent than those in July, August and October. The processing technology of the stem and fruit was consisted of harvest and drying. The quality and character presented no difference after arid or drying at 60 degrees C temperature.