Mesenchymal Stem Cell-Derived Exosomes are Effective for Radiation Enteritis and Essential for the Proliferation and Differentiation of Lgr5+ Intestinal Epithelial Stem Cells by Regulating Mir-195/Akt/β-Catenin Pathway

Yang Leilei,Fang Chengfeng,Song Caifang,Zhang Yaya,Zhang Ruili,Zhou Shenkang 한국조직공학과 재생의학회 2023 조직공학과 재생의학 Vol.20 No.5

BACKGROUND: Radiation enteritis (RE) is a common complication of abdominal or pelvic radiotherapy, which when severe, could be life-threatening. Currently, there are no effective treatments. Studies have shown that mesenchymal stem cells (MSCs)-derived exosomes (MSC-exos) exhibit promising therapeutic effects in inflammatory diseases. However, the specific role of MSC-exos in RE and the regulatory mechanisms remain elusive. METHODS: In vivo assay was carried out by injecting MSC-exos into the total abdominal irradiation (TAI)-induced RE mouse model. For in vitro assay, Lgr5-positive intestinal epithelial stem cells (Lgr5? IESC) were extracted from mice, followed by irradiation along with MSC-exos treatment. HE staining was performed to measure histopathological changes. mRNA expression of inflammatory factors TNF-a and IL-6 and stem cell markers LGR5, and OCT4 were quantified by RT-qPCR. EdU and TUNEL staining was performed to estimate cell proliferation and apoptosis. MiR-195 expression in TAI mice and radiation-induced Lgr5? IESC was tested. RESULTS: We found that the injection of MSC-exos inhibited inflammatory reaction, increased stem cell marker expression, and maintained intestinal epithelial integrity in TAI mice. Furthermore, MSC-exos treatment increased the proliferation and simultaneously suppressed apoptosis in radiation-stimulated Lgr5? IESC. MiR-195 expression increased by radiation exposure was decreased by MSC-exos therapy. MiR-195 overexpression facilitated the progress of RE by counteracting the effect of MSC-exos. Mechanistically, the Akt and Wnt/b-catenin pathways inhibited by MSC-exos were activated by miR-195 upregulation. CONCLUSION: MSC-Exos are effective in treating RE and are essential for the proliferation and differentiation of Lgr5? IESCs. Moreover, MSC-exos mediates its function by regulating miR-195 Akt b-catenin pathways.

Imprinted gene expression in maize starchy endosperm and aleurone tissues of reciprocal F1 hybrids at a defined developmental stage

Meishan Zhang,Ruili Lv,Wei Yang,Tiansi Fu,Bao Liu 한국유전학회 2018 Genes & Genomics Vol.40 No.1

Imprinted gene expression in flowering plants predominantly occurs in the triploid endosperm of developing seed. However, endosperm is composed of distinct tissue types. For example, the maize (Zea mays) endosperm is constituted by two major tissues, starchy endosperm and aleurone. Previous studies in imprinted gene expression have generally assumed that the different tissues constituting endosperm would behavior the same, and hence have not examined them separately. Here, to examine parentalspecific expression of imprinted genes in different parts of the seed, eight previously reported maize protein-coding imprinted genes were selected, and analyzed by cleaved amplified polymorphic sequence (CAPS) coupled with Sanger sequencing for transcripts from the various seed tissues collected at 18 days after pollination (DAP). The studied tissues included seed coat, embryo, starchy endosperm and aleurone, which were collected from a pair of reciprocal F1 hybrids produced by crossing inbred lines B73 and Mo17. Six of these eight analyzed imprinted genes showed the same imprinted expression pattern between the starchy endosperm and aleurone, but two showed imprinted expression only in the starchy endosperm. Comparison of the expression pattern of 20 selected imprinted genes in multiple seed tissues and vegetative tissues indicated that the majority (~ 75%) of these imprinted genes exhibited seedspecific or endosperm-specific expression. Our results also uncovered that imprinted genes have a high propensity to be alternatively spliced via intron retention in the developing embryo compared with the other tissues.

Analysis of Microbial Diversity in Tomato Paste Wastewater through PCR-DGGE

Shiyang Sun,Zhiguo Guo,Ruili Yang,Zhigang Sheng,Peng Cao 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.1

This study was conducted to evaluate the relationship between the flora and the changes in the microbial communities during tomato paste wastewater treatment. The bio-analytical techniques like Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE), adenosine-triphosphate (ATP) analysis, and testing of mixed liquid and suspended solids (MLSS) were simultaneously conducted to analyze the dynamics of the microbial communities during tomato paste wastewater treatment process. The study suggests that the combined approaches of PCR-DGGE, ATP, and MLSS provided a simple and accurate method to evaluate the changes in microbial activity, microbial structure, and population size with the shift in contaminants in different treatment processes. The study also demonstrates that the structure and quantity of a microbial community are influenced by MLSS during the wastewater treatment process, which consequently determines the overall functionality of the system.

Numerical Simulation of Prestressed Precast Concrete Bridge Deck Panels Using Damage Plasticity Model

Wei Ren,Lesley H. Sneed,Yang Yang,Ruili He 한국콘크리트학회 2015 International Journal of Concrete Structures and M Vol.9 No.1

This paper describes a three-dimensional approach to modeling the nonlinear behavior of partial-depth precast prestressed concrete bridge decks under increasing static loading. Six full-size panels were analyzed with this approach where the damage plasticity constitutive model was used to model concrete. Numerical results were compared and validated with the experimental data and showed reasonable agreement. The discrepancy between numerical and experimental values of load capacities was within six while the discrepancy of mid-span displacement was within 10 %. Parametric study was also conducted to show that higher accuracy could be achieved with lower values of the viscosity parameter but with an increase in the calculation effort.

Super-Resolution Reconstruction based on Tukey Norm and Adaptive Bilateral Total Variation

Jie Shen,Feng Xu,Mengxi Xu,Yun Yang,Ruili Wang,Lili Zhang 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.5

In Bilateral Total Variation (BTV) regularized super-resolution reconstruction (SRR), the fidelity item is only applicable to a specific noise model, and the fixed weight of BTV regularization term cannot adapt to the changes in an image. Thus, this paper proposes a SRR algorithm based on the Tukey fidelity term and adaptive BTV regularization term. The Tukey fidelity term has a more effective outliers suppression feature to deal with complex noises, and the weight of adaptive BTV regularization term can resize itself according to the changes of image textures, which can achieve the purposes of suppressing noises and preserving edges. Experimental results show that, compared with other algorithms, the proposed algorithm has better vision effects and higher Peak Signal-to-noise Ratio (PSNR) values.

The Characterization of Hemicellulose Extract from Corn Stalk with Stepwise Alkali Extraction

Rui Li,Guihua Yang,Jiachuan Chen,Ming He 한국펄프·종이공학회 2017 펄프.종이技術 Vol.49 No.4

In this paper, the stepwise alkaline extraction and structural characterization of hemicelluloses in corn stalk were conducted, and the theoretical support for the application of hemicelluloses was provided. Stepwise alkaline extraction of dewaxed corn stalk was performed with water, KOH aqueous solution (0.6%, 1.0%, 1.5%, and 2.0%) and a mixture of KOH solution and ethanol with a volume ratio of 2:3, and under these conditions, 2.6%, 10.2%, 16.5%, 24.8%, 11.2% and 8.7% of total hemicelluloses were extracted from corn stalk, respectively. The six types of hemicelluloses from different KOH concentration extraction process were characterized by high performance anion exchange chromatography, Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analyzer (TG), carbon-13 magnetic resonance spectroscopy (13C-NMR) and hydrogen-1magnetic resonance spectroscopy (1H-NMR). Xylose was the predominant sugar constituent in the six types of hemicelluloses, and arabinose, glucose and galactose were present in small amounts. The straight chain and higher thermal stability hemicellulose can be obtained at optimal alkali concentration. An optimal alkali solution concentration was found to be at 1.5% KOH with the higher yield, xylose content and thermal stability of the hemicelluloses. NMR analysis showed that the alkaline extraction of the corn stalk with 1.5% KOH did not result in any obvious change in the macromolecular structure of hemicelluloses.