Hypoxia Mediates Runt-Related Transcription Factor 2 Expression via Induction of Vascular Endothelial Growth Factor in Periodontal Ligament Stem Cells

Manjing Deng,Qian Xu,Zhihua Liu1,Ling Guo,Rui Liu,Rulei Li,Xiang Chu,Jiajia Yang,Jia Luo,Faming Chen 한국분자세포생물학회 2019 Molecules and cells Vol.42 No.11

Periodontitis is characterized by the loss of periodontal tissues, especially alveolar bone. Common therapies cannot satisfactorily recover lost alveolar bone. Periodontal ligament stem cells (PDLSCs) possess the capacity of self-renewal and multilineage differentiation and are likely to recover lost alveolar bone. In addition, periodontitis is accompanied by hypoxia, and hypoxia-inducible factor-1α (HIF-1α) is a master transcription factor in the response to hypoxia. Thus, we aimed to ascertain how hypoxia affects runt-related transcription factor 2 (RUNX2), a key osteogenic marker, in the osteogenesis of PDLSCs. In this study, we found that hypoxia enhanced the protein expression of HIF-1α, vascular endothelial growth factor (VEGF), and RUNX2 ex vivo and in situ. VEGF is a target gene of HIF-1α, and the increased expression of VEGF and RUNX2 proteins was enhanced by cobalt chloride (CoCl2, 100 μmol/L), an agonist of HIF-1α, and suppressed by 3-(5′-hydroxymethyl-2′-furyl)-1-benzyl indazole (YC-1, 10 μmol/L), an antagonist of HIF-1α. In addition, VEGF could regulate the expression of RUNX2, as RUNX2 expression was enhanced by human VEGF (hVEGF165) and suppressed by VEGF siRNA. In addition, knocking down VEGF could decrease the expression of osteogenesis-related genes, i.e., RUNX2, alkaline phosphatase (ALP), and type I collagen (COL1), and hypoxia could enhance the expression of ALP, COL1, and osteocalcin (OCN) in the early stage of osteogenesis of PDLSCs. Taken together, our results showed that hypoxia could mediate the expression of RUNX2 in PDLSCs via HIF-1α-induced VEGF and play a positive role in the early stage of osteogenesis of PDLSCs

5-Aza-2'-deoxycytidine Induces Hepatoma Cell Apoptosis via Enhancing Methionine Adenosyltransferase 1A Expression and Inducing S-Adenosylmethionine Production

Liu, Wei-Jun,Ren, Jian-Guo,Li, Ting,Yu, Guo-Zheng,Zhang, Jin,Li, Chang-Sheng,Liu, Zhi-Su,Liu, Quan-Yan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

In hepatocellular cancer (HCC), lack of response to chemotherapy and radiation treatment can be caused by a loss of epigenetic modifications of cancer cells. Methionine adenosyltransferase 1A is inactivated in HCC and may be stimulated by an epigenetic change involving promoter hypermethylation. Therefore, drugs releasing epigenetic repression have been proposed to reverse this process. We studied the effect of the demethylating reagent 5-aza-2'-deoxycitidine (5-Aza-CdR) on MAT1A gene expression, DNA methylation and S-adenosylmethionine (SAMe) production in the HCC cell line Huh7. We found that MAT1A mRNA and protein expression were activated in Huh7 cells with the treatment of 5-Aza-CdR; the status of promoter hypermethylation was reversed. At the same time, MAT2A mRNA and protein expression was significantly reduced in Huh7 cells treated with 5-Aza-CdR, while SAMe production was significantly induced. However, 5-Aza-CdR showed no effects on MAT2A methylation. Furthermore, 5-Aza-CdR inhibited the growth of Huh7 cells and induced apoptosis and through down-regulation of Bcl-2, up-regulation of Bax and caspase-3. Our observations suggest that 5-Aza-CdR exerts its anti-tumor effects in Huh7 cells through an epigenetic change involving increased expression of the methionine adenosyltransferase 1A gene and induction of S-adenosylmethionine production.

Effects of a multi-strain probiotic on growth, health, and fecal bacterial flora of neonatal dairy calves

Guo Yongqing,Li Zheng,Deng Ming,Li Yaokun,Liu Guangbin,Liu Dewu,Liu Qihong,Liu Qingshen,Sun Baoli 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.2

Objective: The aim of this study was to investigate the effects of dietary supplementation with a multi-strain probiotic (MSP) product containing of Bifidobacterium animalis, Lactobacillus casei, Streptococcus faecalis, and Bacillus cerevisiae on growth, health, and fecal bacterial composition of dairy calves during the first month of life. Methods: Forty Holstein calves (24 female and 16 male) at 2 d of age were grouped by sex and date of birth then randomly assigned to 1 of 4 treatments: milk replacer supplementation with 0 g (0MSP), 2 g (2MSP), 4 g (4MSP), and 6 g (6MSP) MSP per calf per day. Results: Supplementation of MSP did not result in any significant differences in parameters of body measurements of calves during the 30 d period. As the dosage of MSP increased, the average daily gain (p = 0.025) and total dry matter intake (p = 0.020) of calves showed a linear increase. The fecal consistency index of the 2MSP, 4MSP, and 6MSP group calves were lower than that of the 0MSP group calves (p = 0.003). As the dosage of MSP increased, the concentrations of lactate dehydrogenase (p = 0.068) and aspartate aminotransferase (p = 0.081) in serum tended to decrease, whereas the concentration of total cholesterol increased quadratically (p = 0.021). The relative abundance of Dorea in feces was lower (p = 0.011) in the 2MSP, 4MSP, and 6MSP group calves than that in the 0MSP group calves. The relative abundance of Dorea (p = 0.001), Faecalibacterium (p = 0.050), and Mitsuokella (p = 0.030) decreased linearly, whereas the relative abundance of Prevotella tended to increase linearly as the dosage of MSP increased (p = 0.058). Conclusion: The MSP product can be used to reduce the diarrhea, improve the performance, and alter the composition of the fecal bacteria in neonatal dairy calves under the commercial conditions. Objective: The aim of this study was to investigate the effects of dietary supplementation with a multi-strain probiotic (MSP) product containing of Bifidobacterium animalis, Lactobacillus casei, Streptococcus faecalis, and Bacillus cerevisiae on growth, health, and fecal bacterial composition of dairy calves during the first month of life.Methods: Forty Holstein calves (24 female and 16 male) at 2 d of age were grouped by sex and date of birth then randomly assigned to 1 of 4 treatments: milk replacer supplementation with 0 g (0MSP), 2 g (2MSP), 4 g (4MSP), and 6 g (6MSP) MSP per calf per day.Results: Supplementation of MSP did not result in any significant differences in parameters of body measurements of calves during the 30 d period. As the dosage of MSP increased, the average daily gain (p = 0.025) and total dry matter intake (p = 0.020) of calves showed a linear increase. The fecal consistency index of the 2MSP, 4MSP, and 6MSP group calves were lower than that of the 0MSP group calves (p = 0.003). As the dosage of MSP increased, the concentrations of lactate dehydrogenase (p = 0.068) and aspartate aminotransferase (p = 0.081) in serum tended to decrease, whereas the concentration of total cholesterol increased quadratically (p = 0.021). The relative abundance of Dorea in feces was lower (p = 0.011) in the 2MSP, 4MSP, and 6MSP group calves than that in the 0MSP group calves. The relative abundance of Dorea (p = 0.001), Faecalibacterium (p = 0.050), and Mitsuokella (p = 0.030) decreased linearly, whereas the relative abundance of Prevotella tended to increase linearly as the dosage of MSP increased (p = 0.058).Conclusion: The MSP product can be used to reduce the diarrhea, improve the performance, and alter the composition of the fecal bacteria in neonatal dairy calves under the commercial conditions.

Formation and Characterization of Two-Dimensional Arrays of Silver Oxide Nanoparticles under Langmuir Monolayers of n-Hexadecyl Dihydrogen Phosphate

Hong-Guo Liu,Fei Xiao,Hong-Guo Liu 대한화학회 2008 Bulletin of the Korean Chemical Society Vol.29 No.12

Two-dimensional arrays of silver oxide nanoparticles were prepared by oxidation of silver nanoparticle arrays in air. The silver nanoparticle arrays were formed by illuminating the composite Langmuir monolayers of nhexadecyl dihydrogen phosphate (n-HDP)/ethyl stearate (ES)/Ag+ at the air-water interface by daylight. The average diameters of the nanoclusters is found to be 2.32 ± 0.89, 2.97 ± 0.78, and 4.94 ± 0.57 nm, respectively, depending on the experimental conditions. X-ray photoelectron spectroscopy (XPS), UV-vis spectroscopy and high-resolution transmission electron microscopy (HRTEM) investigations indicate the formation of silver oxide nanoparticles. The possible formation mechanism of the 2D arrays should be attributed to the templating effect of parallel aligned linear supramolecular rows of n-HDP formed at the air-water interface.

Comparative transcriptomic and physiological analyses of contrasting hybrid cultivars ND476 and ZX978 identify important differentially expressed genes and pathways regulating drought stress tolerance in maize

Guo Liu,Tinashe Zenda,Songtao Liu,Xuan Wang,Hongyu Jin,Anyi Dong,Yatong Yang,Huijun Duan 한국유전학회 2020 Genes & Genomics Vol.42 No.8

Background Drought is the major abiotic stress factor that negatively influences growth and yield in cereal grain crops such as maize (Zea mays L.). A multitude of genes and pathways tightly modulate plant growth, development and responses to environmental stresses including drought. Therefore, crop breeding efforts for enhanced drought resistance require improved knowledge of plant drought responses. Objective Here, we sought to elucidate the molecular and physiological mechanisms underpinning maize drought stress tolerance. Methods We therefore applied a 12-day water-deficit stress treatment to maize plants of two contrasting (drought tolerant ND476 and drought sensitive ZX978) hybrid cultivars at the late vegetative (V12) growth stage and performed a large-scale RNA sequencing (RNA-seq) transcriptome analysis of the leaf tissues. Results A comparative analysis of the two genotypes leaf transcriptomes and physiological parameters revealed the key differentially expressed genes (DEGs) and metabolic pathways that respond to drought in a genotype-specific manner. A total of 3114 DEGs were identified, with 21 DEGs being specifically expressed in tolerant genotype ND476 in response to drought stress. Of these, genes involved in secondary metabolites biosynthesis, transcription factor regulation, detoxification and stress defense were highly expressed in ND476. Physiological analysis results substantiated our RNA-seq data, with ND476 exhibiting better cell water retention, higher soluble protein content and guaiacol peroxidase activity, along with low lipid peroxidation extent than the sensitive cultivar ZX978 under drought conditions. Conclusion Our findings enrich the maize genetic resources and enhance our further understanding of the molecular mechanisms regulating drought stress tolerance in maize. Additionally, the DEGs screened in this study may provide a foundational basis for our future targeted cloning studies.

Key Application Technologies of High Efficiency Power Quality Control Systems

Liu, Ding-Guo,Shuai, Zhi-Kang,Tu, Chun-Ming,Cheng, Ying,Luo, An The Korean Institute of Power Electronics 2013 JOURNAL OF POWER ELECTRONICS Vol.13 No.3

Large capacity reactive power compensation and harmonic control in the low-voltage grid of an enterprise, are important technical means to improve power quality and reduce power loss. In this paper, the principle of an efficient power quality controller is analyzed. Then, key application technologies of the HPQC which would influence the performances of the HPQC are studied. Based on an analysis of the harmonic shunt problem, a frequency dividing control strategy of the HPQC continuous subsystem is proposed. A parameter design method of the HPQC discrete subsystem and its installation method are also proposed to ensure the system compensation effect. HPQC systems have been designed for a copper foil plant. The effectiveness of this paper has been verified by the simulation and application results.

The Stand and Prospect of Laws on Migration in China ; Critical Reflection on the Law of Exit and Entry Administration of China 2013

( Guo Fu Liu ) 건국대학교 법학연구소 2015 一鑑法學 Vol.0 No.30

2013년 중국 이민법은 중국 내 국제 거주 구역에서 가장 중요한 법이며, 1985년 중국 이민법 이후 가장 큰 점검을 마쳤다. 이 법은 중국 내외 이주를 규제할 뿐만 아니라, 중국의 외환과 개화를 촉진하기도 한다. 중국 이민법은 이 법이 구축하는 이민 제도 내에 결점을 가지고 있으며, 따라서 시행 세칙에도 결점이 있다. 이 법을 효과적으로 시행하고, 시행 세칙을 준비하는 동안, 법 집행의 영향을 조심스럽게 고려해 봐야 하며, 이 법의 단점을 정확하게 명시하는 것이 필요하다. Law in international migration area in China, and the biggest overhaul of China’s exit and entry administration law since 1985. This Law not only regulates China’s exit and entry administration, but also promotes China’s foreign exchanges and opening to the outside world. The LEEA as promulgated has deficiencies in the immigration system it establishes and thus its implementing regulations. To implement this Law efficiently, it is imperative to carefully consider its impacts and address the Law’s deficiencies while the implementing regulations are being prepared.

A MODIFIED BFGS BUNDLE ALGORITHM BASED ON APPROXIMATE SUBGRADIENTS

Guo, Qiang,Liu, Jian-Guo The Korean Society for Computational and Applied M 2010 Journal of applied mathematics & informatics Vol.28 No.5

In this paper, an implementable BFGS bundle algorithm for solving a nonsmooth convex optimization problem is presented. The typical method minimizes an approximate Moreau-Yosida regularization using a BFGS algorithm with inexact function and the approximate gradient values which are generated by a finite inner bundle algorithm. The approximate subgradient of the objective function is used in the algorithm, which can make the algorithm easier to implement. The convergence property of the algorithm is proved under some additional assumptions.

A novel method for identifying rotor-stator rubbing positions using the cepstrum analysis technique

Guo Chen,Yong-Quan Liu,Guang-Yi Jiang,Cheng-Gang Li,Guo-Quan Feng,De-You Wang 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.9

A novel method of aero-engine rubbing positions identification based on cepstrum analysis is proposed, and the transfer path characteristicswhich reflect the transfer characteristics information from rubbing points to casing measuring points are separated from the vibrationacceleration signals of casing by means of cepstrum analysis. Therefore, there is different transfer characteristics information atdifferent rubbing positions, and in view of this, twenty rubbing positions identification features from the cepstrum are extracted. A largenumber of rubbing experiments of different positions are simulated with the rotor experiment rig of aero-engine, and the characteristicanalysis of experimental samples at different rubbing positions is carried out, and the results indicate the consistency of features to thesame rubbing position and the difference of the features to the different rubbing positions. Finally, the aero-engine rubbing positionsidentification is carried out using the nearest neighbor classification method, the recognition rate reaches 100%, and the effectiveness ofthe method is full verified.

GLOBAL CONVERGENCE PROPERTIES OF THE MODIFIED BFGS METHOD ASSOCIATING WITH GENERAL LINE SEARCH MODEL

Liu, Jian-Guo,Guo, Qiang 한국전산응용수학회 2004 Journal of applied mathematics & informatics Vol.16 No.1

To the unconstrained programme of non-convex function, this article give a modified BFGS algorithm. The idea of the algorithm is to modify the approximate Hessian matrix for obtaining the descent direction and guaranteeing the efficacious of the quasi-Newton iteration pattern. We prove the global convergence properties of the algorithm associating with the general form of line search, and prove the quadratic convergence rate of the algorithm under some conditions.