GATA4 Forms a Positive Feedback Loop with CDX2 to Transactivate MUC2 in Bile Acids-Induced Gastric Intestinal Metaplasia

( Xiaofang Yang ),( Ting Ye ),( Li Rong ),( Hong Peng ),( Jin Tong ),( Xiao Xiao ),( Xiaoqiang Wan ),( Jinjun Guo ) 대한소화기기능성질환·운동학회 2024 Gut and Liver Vol.18 No.3

Background/Aims: Gastric intestinal metaplasia (GIM), a common precancerous lesion of gastric cancer, can be caused by bile acid reflux. GATA binding protein 4 (GATA4) is an intestinal transcription factor involved in the progression of gastric cancer. However, the expression and regulation of GATA4 in GIM has not been clarified. Methods: The expression of GATA4 in bile acid-induced cell models and human specimens was examined. The transcriptional regulation of GATA4 was investigated by chromatin immunopre-cipitation and luciferase reporter gene analysis. An animal model of duodenogastric reflux was used to confirm the regulation of GATA4 and its target genes by bile acids. Results: GATA4 expression was elevated in bile acid-induced GIM and human specimens. GATA4 bound to the promoter of mucin 2 (MUC2) and stimulate its transcription. GATA4 and MUC2 expression was positively correlated in GIM tissues. Nuclear transcription factor-κB activation was required for the upregulation of GATA4 and MUC2 in bile acid-induced GIM cell models. GATA4 and caudal-related homeobox 2 (CDX2) reciprocally transactivated each other to drive the transcription of MUC2. In chenodeoxycholic acid-treated mice, MUC2, CDX2, GATA4, p50, and p65 expression levels were increased in the gastric mucosa. Conclusions: GATA4 is upregulated and can form a positive feedback loop with CDX2 to transactivate MUC2 in GIM. NF-κB signaling is involved in the upregulation of GATA4 by chenodeoxycholic acid. (Gut Liver 2024;18:414-425)

ALMOST PERIODIC SOLUTION FOR A n-SPECIES COMPETITION MODEL WITH FEEDBACK CONTROLS ON TIME SCALES

Li, Yongkun,Han, Xiaofang The Korean Society for Computational and Applied M 2013 Journal of applied mathematics & informatics Vol.31 No.1

In this paper, using the time scale calculus theory, we first discuss the permanence of a $n$-species competition system with feedback control on time scales. Based on the permanence result, by the Lyapunov functional method, we establish sufficient conditions for the existence and uniformly asymptotical stability of almost periodic solutions of the considered model. The results of this paper is completely new. An example is employed to show the feasibility of our main result.

Myo-Inositol Attenuates Renal Interstitial Fibrosis in Obstructive Nephropathy by Inhibiting PI3K/AKT Activation

Xiaofang Hu,Ming Yang,Xiangyi Li,Zhicheng Gong,Jianxiu Duan 한국식품영양과학회 2023 Journal of medicinal food Vol.26 No.6

Emerging evidence suggests that myo-inositol (MI) has a critical role in reducing renal inflammatory processes and improving podocyte function and preventing diabetes-related renal damage. We aimed to explore the function and underlying workings of MI in renal interstitial fibrosis (RIF). Based on a mouse model, we explored the effect of MI in unilateral ureteral obstruction (UUO) and in transforming growth factor-β1 (TGF-β1)-treated HK-2 cells. Pathological changes of the kidney tissues were examined following staining of the tissues with hematoxylin, eosin, and Masson's trichrome. The mRNA quantities of fibrosis markers, fibronectin, α-smooth muscle actin (α-SMA), and collagen I, were analyzed by means of real-time polymerase chain reaction, whereas those of protein levels were assessed with Western blotting. We also determined the expression of collagen I by immunofluorescence, and the levels of phosphorylated phosphotidylinositol-3-kinase and protein kinase B (PI3K/AKT) by Western blot. In vivo, histopathological examination in the UUO mice revealed renal tubular epithelial cell necrosis, inflammatory cell infiltration, and RIF. UUO mice showed higher expression levels of collagen I, fibronectin, α-SMA, pPI3K, and pAKT compared with sham-operated mice. However, MI treatment diminished the pathological alterations of RIF in UUO mice and downregulated the expression of fibrosis markers and phosphorylated PI3K/AKT. In vitro, TGF-β1 positively influenced the propagation and differentiation of HK-2 cells and upregulated the levels of α-SMA, fibronectin, collagen I, pPI3K, and pAKT, but these became significantly reversed by MI treatment. In conclusion, MI ameliorates RIF, possibly by negatively regulating TGF-β1-induced epithelial transdifferentiation and PI3K/AKT activation.

Transplantation of Wnt5a-modified NSCs promotes tissue repair and locomotor functional recovery after spinal cord injury

Li Xiang,Peng Zhiming,Long Lingli,Lu Xiaofang,Zhu Kai,Tuo Ying,Chen Ningning,Zhao Xiaoyang,Wang Le,Wan Yong 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Traditional therapeutic strategies for spinal cord injury (SCI) are insufficient to repair locomotor function because of the failure of axonal reconnection and neuronal regeneration in the injured central nervous system (CNS). Neural stem cell (NSC) transplantation has been considered a potential strategy and is generally feasible for repairing the neural circuit after SCI; however, the most formidable problem is that the neuronal differentiation rate of NSCs is quite limited. Therefore, it is essential to induce the neuronal differentiation of NSCs and improve the differentiation rate of NSCs in spinal cord repair. Our results demonstrate that both Wnt5a and miRNA200b-3p could promote NSC differentiation into neurons and that Wnt5a upregulated miRNA200b-3p expression through MAPK/JNK signaling to promote NSC differentiation into neurons. Wnt5a could reduce RhoA expression by upregulating miRNA200b-3p expression to inhibit activation of the RhoA/Rock signaling pathway, which has been reported to suppress neuronal differentiation. Overexpression of RhoA abolished the neurogenic capacity of Wnt5a and miRNA200b-3p. In vivo, miRNA200b-3p was critical for Wnt5a-induced NSC differentiation into neurons to promote motor functional and histological recovery after SCI by suppressing RhoA/Rock signaling. These findings provide more insight into SCI and help with the identification of novel treatment strategies.

ALMOST PERIODIC SOLUTION FOR A n-SPECIES COMPETITION MODEL WITH FEEDBACK CONTROLS ON TIME SCALES

Yongkun Li,Xiaofang Han 한국전산응용수학회 2013 Journal of applied mathematics & informatics Vol.31 No.1

In this paper, using the time scale calculus theory, we firstdiscuss the permanence of a n-species competition system with feedbackcontrol on time scales. Based on the permanence result, by the Lyapunovfunctional method, we establish sufficient conditions for the existence anduniformly asymptotical stability of almost periodic solutions of the consideredmodel. The results of this paper is completely new. An example isemployed to show the feasibility of our main result.

Analysis of Strong Stress Concentrations of Key Joints for Super-Spanned Steel Truss Bridges

Cong Li,Zixin Song,Guanghui Xia,Xiaofang Kang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.7

In this paper, the strategy of three scales was proposed to analyse strong stress distributions of key joints during the incremental launching construction. Firstly, the internal forces and reaction forces were obtained by the finite element method (FEM). Secondly, some key joints were separated from the whole structure. The displacements and boundary conditions of the separated joint were taken from the results of the FEM. Then the stress distributions of the separated joint were successfully obtained by using the FEM. Thirdly, the local stress concentration areas were separated from the key joint structure. The high stress distributions of the local stress concentration region were successfully obtained by using the extended boundary element method (XBEM). On the other hand, the stress of some joints were measured through mechanical test on the construction site. And calculation results of the FEM and XBEM were in good agreement with test results. A multi-scale method is developed to obtain the strong stress concentration during the construction of the super-spanned steel truss bridge accurately, which enables the safety of the construction. In addition, the present method can be further used to guide the design of super-tall building, super-spanned bridge, etc.

IOMMU Para-Virtualization for Efficient and Secure DMA in Virtual Machines

Tang, Hongwei,Li, Qiang,Feng, Shengzhong,Zhao, Xiaofang,Jin, Yan Korean Society for Internet Information 2016 KSII Transactions on Internet and Information Syst Vol.10 No.12

IOMMU is a hardware unit that is indispensable for DMA. Besides address translation and remapping, it also provides I/O virtual address space isolation among devices and memory access control on DMA transactions. However, currently commodity virtualization platforms lack of IOMMU virtualization, so that the virtual machines are vulnerable to DMA security threats. Previous works focus only on DMA security problem of directly assigned devices. Moreover, these solutions either introduce significant overhead or require modifications on the guest OS to optimize performance, and none can achieve high I/O efficiency and good compatibility with the guest OS simultaneously, which are both necessary for production environments. However, for simulated virtual devices the DMA security problem also exists, and previous works cannot solve this problem. The reason behind that is IOMMU circuits on the host do not work for this kind of devices as DMA operations of which are simulated by memory copy of CPU. Motivated by the above observations, we propose an IOMMU para-virtualization solution called PVIOMMU, which provides general functionalities especially DMA security guarantees for both directly assigned devices and simulated devices. The prototype of PVIOMMU is implemented in Qemu/KVM based on the virtio framework and can be dynamically loaded into guest kernel as a module, As a result, modifying and rebuilding guest kernel are not required. In addition, the device model of Qemu is revised to implement DMA access control by separating the device simulator from the address space of the guest virtual machine. Experimental evaluations on three kinds of network devices including Intel I210 (1Gbps), simulated E1000 (1Gbps) and IB ConnectX-3 (40Gbps) show that, PVIOMMU introduces little overhead on DMA transactions, and in general the network I/O performance is close to that in the native KVM implementation without IOMMU virtualization.

Sex pheromone of the jumping plant bug, Halticus minutus Reuter (Hemiptera: Miridae)

Tao Zhang,Xiaofang Zhang,Xiangdong Mei,Yaofa Li,Zhanlin Gao,Jun Ning 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.2

The jumping plant bug, Halticusminutus Reuter, is a pest of sweet potatoes, soybeans and turfgrass in China. Here we present our analysis of the female-produced sex pheromone. These plant bugs release their sex pheromone, consisting hexyl acetate (HA), hexyl butyrate (HB) and (E)-4-oxo-2-hexenal (4-OHE), at night. These three components, tested individually, elicited strong antennal responses. Field tests indicated that a ternary blend of HA, HB and 4-OHE, at ratios of 1:16:10, effectively attractedmale H. minutus. Our dose-response analysis showed optimal male capture at the trap dose of 13.5mg/trap. Higher trap doses did not improve capture rates. Higher ratios of HB in the pheromone mix led to substantially reduced captures, fromwhich we infer that HBmay function as an alarm pheromone or defensive secretion. Pipette tips were used as long-term lures, and whose longevities were evaluated. Results showed effective duration of pipette tip lures were N5 weeks. Thus, we suggest that the pheromone-baited traps are economically viable tools for long-term monitoring and trapping of jumping plant bugs.

Do Foreign Investors Monitor Managers in Merger and Acquisition? Evidence from China

Chao Xu,Xiaofang Zhao,Hao Yang,Shiqing Li 한국증권학회 2022 Asia-Pacific Journal of Financial Studies Vol.51 No.1

Using foreign investors’ shareholding to proxy for foreign investors’ monitoring effect in the Chinese stock market, we find that those acquirers exhibit higher announcement returns with higher shareholding, and this effect is stronger when acquirers are private firms. We provide price efficiency and corporate governance channels through which foreign investors play a monitoring role in mergers and acquisitions. Finally, foreign investors decrease the likelihood that managers will conduct mergers in the future and significantly improve long-run performance. Our study provides new insights into the real effects of foreign investors on acquisition performance and the economy.

Cocktail Formula and Application Prospects for Oral and Maxillofacial Organoids

Ou Mingyu,Li Qing,Ling Xiaofang,Yao Jinguang,Mo Xiaoqiang 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.5

Oral and maxillofacial organoids (OMOs), tiny tissues and organs derived from stem cells cultured through 3-d cell culture models, can fully summarize the cell tissue structure, physiological functions and biological characteristics of the source tissues in the body. OMOs are applied in areas such as disease modelling, developmental and regenerative medicine, drug screening, personalized treatment, etc. Although the construction of organoids in various parts of the oral and maxillofacial (OM) region has achieved considerable success, the existing cocktail formulae (construction strategies) are not widely applicable for tissues of various sources due to factors including the heterogeneity of the source tissues and the dependence on laboratory technology. Most of their formulae are based on growth factor niches containing expensive recombinant proteins with their efficiency remaining to be improved. In view of this, the cocktail formulae of various parts of the OM organs are reviewed with further discussion of the application and prospects for those OMOs to find some affordable cocktail formula with strong operability and high repeatability for various maxillofacial organs. The results may help improve the efficiency of organoid construction in the laboratory and accelerate the pace of the clinical use of organoid technology.