Epigenetic inactivation of ACAT1 promotes epithelial-mesenchymal transition of clear cell renal cell carcinoma

Han Peipei,Wu Shu,Li Limei,Li Danping,Zhao Jun,Zhang Haishan,Wang Yifang,Zhong Xuemin,Zhang Zhe,Li Ping,Matskova Liudmila,Zhou Xiaoying 한국유전학회 2022 Genes & Genomics Vol.44 No.4

Background: Acetyl-CoA acyltransferase 1 (ACAT1) is a key enzyme catalyzing the production of mitochondrial ketone bodies. We have shown that ACAT1 is down-regulated in kidney renal clear cell carcinoma (KIRC) previously. Objective: To investigate the reasons for downregulation of ACAT1 in KIRC and explore the underlying mechanisms involved in metastatic inhibition regulated by ACAT1. Methods: The Gene Expression Omnibus (GEO) database was queried for meta-analysis of ACAT1 mRNA expression in KIRC. The UALCAN website was used to compare the methylation levels of the ACAT1 promoter region in KIRC and normal tissues. RT-qPCR was used to quantitate ACAT1 transcription levels. The GCBI and Tarbase V.8 databases were used to predict miRNAs that may target the mRNA of ACAT1. The correlation between mRNA expression of ACAT1, MMP7 (matrix metallopeptidase 7), CDH1 (E-cadherin), EpCAM (epithelial cell adhesion molecule), and VIM (vimentin) was analyzed. Extracellular MMP7 protein was quantitated using an ELISA assay. Results: The methylation level of the ACAT1 promoter region in KIRC was significantly higher than that in the normal kidney tissues. The ACAT1 mRNA expression in the KIRC cell lines was restored after treatment with 5-aza-dC (p < 0.05). MiR-21-5p is a conserved microRNA targeting ACAT1. It is expressed at a significantly higher level in KIRC than in normal tissues (p < 0.001). MiR-21-5p miRNA expression negatively correlates with ACAT1 mRNA expression. The expression of miR-21-5p is higher at the T3-T4 stages and in the histologic grades G3-G4. Patients with high miR-21-5p expression tended to have lower overall survival, suggesting that miR-21-5p could serve as a potentially valuable diagnostic biomarker for KIRC (AUC = 0.957; p < 0.001). A mimetic of miR-21-5p inhibited the expression of ACAT1 mRNA and protein. In addition, ACAT1 mRNA expression positively correlates with CDH1 and EpCAM but is negatively correlated with VIM. Overexpression of ACAT1 suppresses the secretion of MMP7 in KIRC cells. Conclusion: Expression of ACAT1 in KIRC is controlled at two levels, firstly by the hypermethylation of the ACAT1 promoter region and secondly by overexpression of miR-21-5p. Downregulation of ACAT1 expression correlates with epithelial-mesenchymal transition (EMT).

Thymol Ameliorates Aspergillus fumigatus Keratitis by Downregulating the TLR4/ MyD88/ NF-kB/ IL-1β Signal Expression and Reducing Necroptosis and Pyroptosis

Wang Limei,Yan Haijing,Chen Xiaomeng,Han Lin,Liu Guibo,Yang Hua,Lu Danli,Liu Wenting,Che Chengye 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.1

Fungal keratitis is a refractory kind of keratopathy. We attempted to investigate the antiinflammatory role of thymol on Aspergillus fumigatus (A. fumigatus) keratitis. Wound healing and fluorescein staining of the cornea were applied to verify thymol’s safety. Mice models of A. fumigatus keratitis underwent subconjunctival injection of thymol. The anti-inflammatory roles of thymol were verified by hematoxylin-eosin (HE) staining, slit lamp observation, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blotting. In contrast with the DMSO group, more transparent corneas and less inflammatory cells infiltration were detected in mice treated with 50 μg/ml thymol. Thymol downregulated the synthesis of TLR4, MyD88, NF-kB, IL-1β, NLRP3, caspase 1, caspase 8, GSDMD, RIPK3 and MLKL. In summary, we proved that thymol played a protective part in A. fumigatus keratitis by cutting down inflammatory cells aggregation, downregulating the TLR4/ MyD88/ NF-kB/ IL-1β signal expression and reducing necroptosis and pyroptosis.

Toward integrated Cloud–Fog networks for efficient IoT provisioning: Key challenges and solutions

Peng, Limei,Dhaini, Ahmad R.,Ho, Pin-Han Elsevier 2018 Future generation computer systems Vol.88 No.-

<P><B>Abstract</B></P> <P>Fog computing has been proposed as one of the promising technologies for the construction of a scalable network infrastructure in the user’s vicinity, with the purpose of serving the tremendous amount of daily generated latency-sensitive Internet-of-Things (IoT) data. In provisioning the emerging IoT data in addition to the legacy Cloud services, the Cloud and Fog form a natural continuum of one another and the integration of these two key technologies would offer a promising infrastructure full with IoT resources for IoT data provisioning.</P> <P>In this article, we present iCloudFog, a reconfigurable architecture that enables an agile integration of Fog and Cloud networks. iCloudFog allows to construct different Fog types (i.e., wireless, wired, or hybrid) to fit the different characteristics of IoT devices and data, and Fog nodes. Due to its nature, iCloudFog presents several unique key research challenges that have not yet been addressed in existing literatures, such as network dimensioning and configuration, resource management/QoS, security/privacy, and positioning/localization. We discuss these challenges and suggest promising approaches to resolve them. Effective design and implementation of solutions based on the suggested approaches would allow iCloudFog to play a salient role towards the successful provisioning of future IoT applications and services.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We first provide a literature review of the work related to the integration of Cloud–Fog networks. </LI> <LI> We then present iCloudFog, a scalable and agile integrated Cloud–Fog architecture that provisions Fog and IoT networks dynamically based on the Cloud and IoT nodes’ availability and capability, and network requirements. </LI> <LI> We identify the key challenges that emerge in the process of constructing the iCloudFog framework, such as network dimensioning, security and IoT job scheduling, and indoor localization, and suggest viable approaches to address these challenges. </LI> </UL> </P>

Estimating functional brain networks by incorporating a modularity prior

Qiao, Lishan,Zhang, Han,Kim, Minjeong,Teng, Shenghua,Zhang, Limei,Shen, Dinggang ACADEMIC PRESS 2016 NEUROIMAGE Vol.141 No.-

<P><B>Abstract</B></P> <P>Functional brain network analysis has become one principled way of revealing informative organization architectures in healthy brains, and providing sensitive biomarkers for diagnosis of neurological disorders. Prior to any post hoc analysis, however, a natural issue is how to construct “ideal” brain networks given, for example, a set of functional magnetic resonance imaging (fMRI) time series associated with different brain regions. Although many methods have been developed, it is currently still an open field to estimate biologically meaningful and statistically robust brain networks due to our limited understanding of the human brain as well as complex noises in the observed data. Motivated by the fact that the brain is organized with <I>modular</I> structures, in this paper, we propose a novel functional brain network modeling scheme by encoding a <I>modularity prior</I> under a <I>matrix-regularized</I> network learning framework, and further formulate it as a sparse low-rank graph learning problem, which can be solved by an efficient optimization algorithm. Then, we apply the learned brain networks to identify patients with mild cognitive impairment (MCI) from normal controls. We achieved 89.01% classification accuracy even with a simple feature selection and classification pipeline, which significantly outperforms the conventional brain network construction methods. Moreover, we further explore brain network features that contributed to MCI identification, and discovered potential biomarkers for personalized diagnosis.</P>

A Novel Front-hauling Architecture under Centralized Radio Access Network (C-RAN)

Haoran Mei,Mai Hassan,Limei Peng,Pin Han Ho 한국통신학회 2022 Journal of communications and networks Vol.24 No.3

Residential power line is considered a cost-effectivecommunication media for building a digital indoor distributednetwork thanks to its ubiquity in the indoor environment. This paper investigates a front-hauling system under the splitcentralized radio access network (C-RAN) architecture, aimingto examine the feasibility of implementing common public radiointerface (CPRI) over power line communication (PLC) channels. Particularly, we introduce a novel device called CPRI-PLCgateway (CPG) that provides a virtual CPRI link over the PLCchannel to ensure high reliability and efficiency in delivering theCPRI hyper-frames (HFs) between the data unit (DU) and radiounit (RU). We examine the proposed CPRI over PLC system viaextensive simulations in terms of the achievable throughput andreliability.

Distortion Minimization for Relay Assisted Wireless Multicast

Zhi Chen,Pin-Han Ho,Limei Peng 한국통신학회 2018 Journal of communications and networks Vol.20 No.1

The paper studies the scenario of wireless multicast witha single transmitter and a relay that deliver scalable source symbolsto the receivers in a decode-and-forward (DF) fashion. Withthe end-to-end mean square error distortion (EED) as performancemetric, we firstly derive the EED expression for the L-resolutionscalable source symbol for any receiver. An optimization problemin minimizing the weighted EED is then formulated for finding thepower allocations for all resolution layers at the transmitter andthe relay. Due to nonlinearity of the formulations, we solve the formulatedoptimization problems using a generalized programmingalgorithm for obtaining good sub-optimal solutions. Case studiesare conducted to verify the proposed formulations and solution approaches. The results demonstrate the advantages of the proposedstrategies in the relay-assisted wireless networks for scalable sourcemulticast.

Cognitive-Empowered Femtocells: An Intelligent Paradigm for Femtocell Networks

Wang, Xiaoyu,Ho, Pin-Han,Wong, Alexander,Peng, Limei WILEY INTERSCIENCE 2018 WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Vol.2018 No.-

<P>Deploying femtocells has been taken as an effective solution for removing coverage holes and improving wireless service performance in 3G-beyond wireless networks such as WiMAX and Long Term Evolution (LTE). This article investigates a novel framework of dynamic spectrum management for femtocell networks, called cognitive-empowered femtocells (CEF), aiming at mitigating both cross-tier and intratier interferences with minimum modifications required on the corresponding macrocell network. With the proposed framework, each CEF base station (BS) and the femtocell users can utilize spatiotemporally available radio resources for the access traffic. We conclude that the proposed CEF framework can effectively complement the existing femtocell design and serve as a value-added feature to the state-of-the-art femtocell technologies, while achieving high scalability and interoperability by minimizing the required modifications on the macrocell protocol design.</P>

Conductively coupled flexible silicon electronic systems for chronic neural electrophysiology

Li, Jinghua,Song, Enming,Chiang, Chia-Han,Yu, Ki Jun,Koo, Jahyun,Du, Haina,Zhong, Yishan,Hill, Mackenna,Wang, Charles,Zhang, Jize,Chen, Yisong,Tian, Limei,Zhong, Yiding,Fang, Guanhua,Viventi, Jonathan National Academy of Sciences 2018 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.115 No.41

<P>Materials and structures that enable long-term, intimate coupling of flexible electronic devices to biological systems are critically important to the development of advanced biomedical implants for biological research and for clinical medicine. By comparison with simple interfaces based on arrays of passive electrodes, the active electronics in such systems provide powerful and sometimes essential levels of functionality; they also demand long-lived, perfect biofluid barriers to prevent corrosive degradation of the active materials and electrical damage to the adjacent tissues. Recent reports describe strategies that enable relevant capabilities in flexible electronic systems, but only for capacitively coupled interfaces. Here, we introduce schemes that exploit patterns of highly doped silicon nanomembranes chemically bonded to thin, thermally grown layers of SiO2 as leakage-free, chronically stable, conductively coupled interfaces. The results can naturally support high-performance, flexible silicon electronic systems capable of amplified sensing and active matrix multiplexing in biopotential recording and in stimulation via Faradaic charge injection. Systematic in vitro studies highlight key considerations in the materials science and the electrical designs for high-fidelity, chronic operation. The results provide a versatile route to biointegrated forms of flexible electronics that can incorporate the most advanced silicon device technologies with broad applications in electrical interfaces to the brain and to other organ systems.</P>

5G NR mmWave Indoor Coverage with Massive Antenna System

Syed Hassan Raza Naqvi,Pin Han Ho,Limei Peng 한국통신학회 2021 Journal of communications and networks Vol.23 No.1

In this paper, we introduce a novel mmWave access architecture,called mmWave over cable (mmWoC), for achieving effectiveindoor coverage, which is characterized by using an analogmodulated relay link to transport the outdoor mmWave signalsto the indoors. To enable an effective mapping of radio signals onthe cable sub-carriers, we introduce non-configurable air-to-cable(NC-A2C) scheduler that is characterized by its low control complexityand hardware requirement. We will discuss the merits ofthe proposed mmWoC access architecture and the NC-A2C scheduler,which are further validated via extensive simulations.

Inactivation of epithelial sodium ion channel molecules serves as effective diagnostic biomarkers in clear cell renal cell carcinoma

Zheng Qian,Wang Yifang,Zhao Ran,Han Peipei,Zhao Jun,Li Limei,Zhou Xiaohui,Li Ping,Mo Yingxi,Pan Xinli,Luo Wenqi,Zhou Xiaoying 한국유전학회 2023 Genes & Genomics Vol.45 No.7

Background Non-voltage-gated sodium channel, also known as the epithelial sodium channel (ENaC), formed by heteromeric complexes consisting of SCNN1A, SCNN1B, and SCNN1G, is responsible for maintaining sodium ion and body fluid homeostasis in epithelial cells. However, no systematic study of SCNN1 family members has been conducted in renal clear cell carcinoma (ccRCC) to date. Objective To investigate the abnormal expression of SCNN1 family in ccRCC and its potential correlation with clinical parameters. Methods The transcription and protein expression levels of SCNN1 family members in ccRCC were analyzed based on the TCGA database, and were confirmed by quantitative RT-PCR and immunohistochemical staining assays, respectively. The area under curve (AUC) was used to evaluate the diagnostic value of SCNN1 family members for ccRCC patients. Results The mRNA and protein expression of SCNN1 family members was significantly downregulated in ccRCC compared with normal kidney tissues, which might be due to DNA hypermethylation in the promoter region. It is worth noting that the AUC of SCNN1A, SCNN1B, and SCNN1G were 0.965, 0.979, and 0.988 based on the TCGA database (p < 0.0001), respectively. The diagnostic value was even higher when combing these three members together (AUC = 0.997, p < 0.0001). Intriguingly, the mRNA level of SCNN1A was significantly lower in females compared with males, while SCNN1B and SCNN1G were increased with the progression of ccRCC and remarkably associated with a worse outcome for patients. Conclusion The aberrantly decrease of SCNN1 family members might serve as valuable biomarkers for the diagnosis of ccRCC.