The developmental potential of caprine fetal fibroblast nuclei after in vitro transfection and nuclear transfer (NT) into enucleated, in vitro-matured oocytes was evaluated. Fetal fibroblasts were isolated from Day 27 to Day 30 fetuses from a dwarf breed of goat (BELE: breed early lactate early). Cells were transfected with constructs containing the enhanced green fluorescent protein (eGFP) and neomycin resistance genes and were selected with G418. Three eGFP lines and one nontransfected line were used as donor cells in NT. Donor cells were cultured in Dulbecco minimum Eagle medium plus 0.5% fetal calf serum for 4-8 days prior to use in NT. Immature oocytes were recovered by laparoscopic ovum pick-up and matured for 24 h prior to enucleation and NT. Reconstructed embryos were transferred as cleaved embryos into synchronized recipients. A total of 27 embryos derived from transgenic cells and 70 embryos derived from nontransgenic cells were transferred into 13 recipients. Five recipients (38%) were confirmed pregnant at Day 35 by ultrasound. Of these, four recipients delivered five male kids (7.1% of embryos transferred) derived from the nontransfected line. One recipient delivered a female kid derived from an eGFP line (7.7% of embryos transferred for that cell line). Presence of the eGFP transgene was confirmed by polymerase chain reaction, Southern blotting, and fluorescent in situ hybridization analyses. Nuclear transfer derivation from the donor cells was confirmed by single-strand confirmation polymorphism analysis. These results demonstrate that both in vitro-transfected and nontransfected caprine fetal fibroblasts can direct full-term development following NT.
considered as one of the most promising green-energy technologies. [1][2][3][4] From the past several years, with the advents of start-of-the-art Y-series non-fullerene acceptors (NFAs) (Y6, Y6-BO, BTIC-2Cl-γCF 3 , BTP-eC9, L8-BO, and so on) in terms of novel electron-deficient core, dithienothiophen[3.2-b]pyrrolobenzothiadiazole, BTP, [5][6][7][8][9][10] the recording power conversion efficiencies (PCEs) have exceeded 19% in single-junction configuration and over 20% certified PCE based on tandem solar cells has been reported recently. [11,12] As the exciton splitting, charge generation, transport, and extraction are highly dependent on the microstructure morphology and mesoscopic aggregation state in bulk heterojunction (BHJ) photoactive layer. [13] Correspondingly, considerable morphology control strategies have been proposed to enhance crystallinity and manipulate phase separation behaviors for the promotion of photovoltaic characteristics. For example, solvent additive engineering is a promising approach to fine-tune nanomorphology. Despite the increment of performance, such a strategy worsen the device reproducibility and long-term operational stability due to the low volatilization property. [14][15][16][17] Besides, the ternary blend (introducing a third Volatile solids with symmetric π-backbone are intensively implemented on manipulating the nanomorphology for improving the operability and stability of organic solar cells. However, due to the isotropic stacking, the announced solids with symmetric geometry cannot modify the microscopic phase separation and component distribution collaboratively, which will constrain the promotion of exciton splitting and charge collection efficiency. Inspired by the superiorities of asymmetric configuration, a novel process-aid solid (PAS) engineering is proposed. By coupling with BTP core unit in Y-series molecule, an asymmetric, volatile 1,3-dibromo-5-chlorobenzene solid can induce the anisotropic dipole direction, elevated dipole moment, and interlaminar interaction spontaneously. Due to the synergetic effects on the favorable phase separation and desired component distribution, the PAS-treated devices feature the evident improvement of exciton splitting, charge transport, and collection, accompanied by the suppressed trap-assisted recombination. Consequently, an impressive fill factor of 80.2% with maximum power conversion efficiency (PCE) of 18.5% in the PAS-treated device is achieved. More strikingly, the PAStreated devices demonstrate a promising thickness-tolerance character, where a record PCE of 17.0% is yielded in PAS devices with a 300 nm thickness photoactive layer, which represents the highest PCE for thick-film organic solar cells.
BackgroundInsulin-like growth factor binding protein-2 (IGFBP-2) is a secreted protein that binds and regulates IGF actions in controlling growth, development, reproduction, and aging. Elevated expression of IGFBP-2 is often associated with progression of many types of cancers.Methodology/Principal FindingsWe report the identification and characterization of two IGFBP-2 genes in zebrafish and four other teleost fish. Comparative genomics and structural analyses suggest that they are co-orthologs of the human IGFBP-2 gene. Biochemical assays show that both zebrafish igfbp-2a and -2b encode secreted proteins that bind IGFs. These two genes exhibit distinct spatiotemporal expression patterns. During embryogenesis, IGFBP-2a mRNA is initially detected in the lens, then in the brain boundary vasculature, and subsequently becomes highly expressed in the liver. In the adult stage, liver has the highest levels of IGFBP-2a mRNA, followed by the brain. Low levels of IGFBP-2a mRNA were detected in muscle and in the gonad in male adults only. IGFBP-2b mRNA is detected initially in all tissues at low levels, but later becomes abundant in the liver. In adult males, IGFBP-2b mRNA is only detected in the liver. In adult females, it is also found in the gut, kidney, ovary, and muscle. To gain insights into how the IGFBP-2 genes may have evolved through partitioning of ancestral functions, functional and mechanistic studies were carried out. Expression of zebrafish IGFBP-2a and -2b caused significant decreases in the growth and developmental rates and their effects are comparable to that of human IGFBP-2. IGFBP-2 mutants with altered IGF binding-, RGD-, and heparin-binding sites were generated and their actions examined. While mutating the RGD and heparin binding sites had little effect, altering the IGF binding site abolished its biological activity.Conclusions/SignificanceThese results suggest that IGFBP-2 is a conserved regulatory protein and it inhibits growth and development primarily by binding to and inhibiting IGF actions in vivo. The duplicated IGFBP-2 genes may provide additional flexibility in the regulation of IGF activities.
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