31 results on '"Xiaohai Wang"'
Search Results
2. Analytical solution of stochastic real‐time dispatch incorporating wind power uncertainty characterized by Cauchy distribution
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Shuwei Xu, Wenchuan Wu, Yue Yang, Bin Wang, and Xiaohai Wang
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Wind power plants ,Optimisation techniques ,Control of electric power systems ,Other topics in statistics ,Power system management, operation and economics ,Renewable energy sources ,TJ807-830 - Abstract
Abstract Real‐time power dispatch can coordinate wind farms, automatic generation control units and non‐automatic generation control units. In real‐time power dispatch, the probable wind power forecast errors should be appropriately formulated to ensure system security with high probability and minimize operational cost. Previous studies and the authors' onsite tests show that Cauchy distribution effectively fits the “leptokurtic” feature of small‐timescale wind power forecast errors distributions. In this paper, a chance‐constrained real‐time dispatch model with the wind power forecast errors represented by multivariate Cauchy distribution is proposed. Since the Cauchy distribution is stable and has promising mathematical characteristics, the proposed chance‐constrained real‐time dispatch model can be analytically transformed to a convex optimization problem considering the dependence among wind farms’ outputs. Moreover, the proposed model incorporates an affine control strategy compatible with automatic generation control systems. This strategy makes the chance‐constrained real‐time dispatch adaptively take into account both the potential power ramping requirement and power variation on transmission lines caused by the generation adjustment to offset the wind power forecast errors in real‐time power dispatch stage. Numerical test results show that the proposed method is reliable and effective. Meanwhile it is very efficient and suitable for real‐time application.
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- 2021
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3. Loss of exosomal miR-146a-5p from cancer-associated fibroblasts after androgen deprivation therapy contributes to prostate cancer metastasis
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Yu Zhang, Jing Zhao, Mao Ding, Yiming Su, Di Cui, Chenyi Jiang, Sheng Zhao, Gaozhen Jia, Xiaohai Wang, Yuan Ruan, Yifeng Jing, Shujie Xia, and Bangmin Han
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Prostate cancer ,Androgen deprivation therapy (ADT) ,Metastasis ,Cancer-associated fibroblasts (CAFs) ,Exosomes ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Androgen deprivation therapy (ADT) is the backbone of therapy for advanced prostate cancer (PCa). Despite the good initial response, castration resistance and metastatic progression will inevitably occur. Cancer-associated fibroblasts (CAFs) may be implicated in promoting metastasis of PCa after ADT. Our aim is to investigate the role and mechanism of CAFs-derived exosomes involving in metastasis of PCa after ADT. Methods PCa cells were co-cultured with exosomes derived from 10 nM dihydrotestosterone (DHT)-treated (simulating the high androgen level of prostate cancer microenvironment) or ethanol (ETOH) -treated (simulating the castration level of prostate cancer microenvironment after ADT) CAFs, and their migration and invasion differences under castration condition were examined both in vitro and in vivo. The miRNA profiles of exosomes derived from DHT-treated CAFs and matched ETOH-treated CAFs were analysed via next generation sequencing. The transfer of exosomal miR-146a-5p from CAFs to PCa cells was identified by fluorescent microscopy. The function and direct target gene of exosomal miR-146a-5p in PCa cells were confirmed through Transwell assays, luciferase reporter, and western blot. Results Compared with DHT-treated CAFs, exosomes derived from ETOH-treated CAFs dramatically increased migration and invasion of PCa cells under castration condition. MiR-146a-5p level in exosomes from ETOH-treated CAFs was significantly reduced. The loss of miR-146a-5p may strengthen the epithelial-mesenchymal transition (EMT) to accelerate cancer cells metastasis by modulating epidermal growth factor receptor (EGFR)/ERK pathway. Conclusions CAFs-derived exosomal miR-146a-5p confers metastasis in PCa cells under ADT through the EGFR/ERK pathway and it may present a new treatment for PCa.
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- 2020
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4. A Modified Technique of Thulium Laser Enucleation for Benign Prostatic Hyperplasia With Non-morcellator Approach
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Yifeng Jing, Qian Sun, Wenhuan Guo, Dapeng Zhou, Yiping Zhu, Yuyang Zhao, Di Cui, Xiaohai Wang, Yuan Ruan, Fujun Zhao, Shujie Xia, and Bangmin Han
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benign prostatic hyperplasia ,enucleation ,morcellator ,thulium laser ,modified technique ,Surgery ,RD1-811 - Abstract
Background: Until recently, most enucleation techniques of the prostate were performed with the application of morcellator. We introduce a modified enucleation technique of thulium laser with non-morcellator approach, which is about incising and vaporizing remaining prostate tissue instead of a morcellator.Methods: A retrospective evaluation of 223 patients undergoing ThuLEP from January 2014 to December 2015 was performed in our institution. One hundred five of the patients used morcellator while the other 118 used non-morcellator approach. All patients were assessed with the International Prostate Symptom Score (IPSS), quality of life (Qol), ultrasonography, serum prostate-specific antigen (PSA), maximal urine flow rate (Qmax), and postvoid residual urine volume (PVR). We reassessed these parameters at 1-, 3-, 6-, and 12-months after operation. Operative time, perioperative, and postoperative complications were also recorded.Results: Significant improvement was noted in the IPSS, QoL, Qmax, and PVR in both groups at the 12-month follow-up, and assessment showed no differences in these parameters between the two groups. Comparisons of the total operation time and enucleation time demonstrated no significant differences between the two groups. Our non-morcellator approach needed more time to incise and vaporize the enucleated tissue compared to morcellation when the prostate volume was about 40–80 ml (p < 0.05), while it showed a significant lower rate of superficial bladder injury than using morcellator (p < 0.05). There were no significant differences in other complications between the two groups (p > 0.05).Conclusions: Our modified technique is a safe and effective procedure for the treatment of BPH avoiding the potential complications caused by morcellator.
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- 2021
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5. Endothelial Cells Promote Docetaxel Resistance of Prostate Cancer Cells by Inducing ERG Expression and Activating Akt/mTOR Signaling Pathway
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Wenhao Zhou, Yiming Su, Yu Zhang, Bangmin Han, Haitao Liu, and Xiaohai Wang
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endothelial cells ,docetaxel ,chemoresistance ,prostate cancer ,FGF2 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Docetaxel is a first-line chemotherapy for the treatment of patients with castration-resistant prostate cancer (CRPC). Despite the good initial response of docetaxel, drug resistance will inevitably occur. Mechanisms underlying docetaxel resistance are not well elaborated. Endothelial cells (ECs) have been implicated in the progression and metastasis of prostate cancer. However, little attention has been paid to the role of endothelial cells in the development of docetaxel resistance in prostate cancer. Here, we sought to investigate the function and mechanism of endothelial cells involving in the docetaxel resistance of prostate cancer. We found that endothelial cells significantly promoted the proliferation of prostate cancer cells and decreased their sensitivity to docetaxel. Mechanistically, basic fibroblast growth factor (FGF2) secreted by endothelial cells leads to the upregulation of ETS related gene (ERG) expression and activation of the Akt/mTOR signaling pathway in prostate cancer cells to promote docetaxel resistance. In summary, these findings demonstrate a microenvironment-dependent mechanism mediating chemoresistance of prostate cancer and suggest that targeting FGF/FGFR signaling might represent a promising therapeutic strategy to overcome docetaxel resistance.
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- 2020
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6. Endothelial cells promote metastasis of prostate cancer by enhancing autophagy
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Ruizhe Zhao, Xiaoyu Bei, Boyu Yang, Xiaohai Wang, Chenyi Jiang, Fei Shi, Xingjie Wang, Yiping Zhu, Yifeng Jing, Bangmin Han, Shujie Xia, and Qi Jiang
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Endothelial cells ,Autophagy ,Androgen receptor ,Metastasis ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Prostate cancer is one of the most common malignancies. Increasing evidence suggested that endothelial cells may contribute to prostate cancer progression and metastasis. Most recently, autophagy has been proposed to plays a significant role in tumorigenesis and metastasis. Also, it is reported that downregulation of androgen receptor (AR) induces autophagy in prostate cancer cells. However, the underlying mechanisms remain unclear. Here, we aim to explore the role and mechanisms of endothelial cell in prostate cancer progression. Methods The coculture system was established to test the effect of endothelial cells on prostate cancer cells. We performed antibody array and ELISA were used to profile the cytokine expression pattern of endothelial cells in supernatant. Western blot and RT-PCR were used to determine the mechanism by endothelial cells to promote invasion ability of prostate cancer cells. Maraviroc and chloroquine were used to block the CCL5/CCR5 and autophagy pathway respectively. Orthotopic xenograft mouse models and drug treatment study were conducted to determine the role of endothelial cells in promoting metastatic potential in vivo. Results We use CPRC prostate cancer model and demonstrate that endothelial cells secrete large amount of CCL5 and induces autophagy by suppressing AR expression in prostate cancer cell lines. Consequently, elevated autophagy accelerates focal adhesions proteins disassembly and promoted prostate cancer invasion. Inhibition of both CCL5/CCR5 signaling and autophagy significantly reduces metastasis in vivo. Conclusions Together, our data establish the function for endothelial cells in tumor metastasis and propose new drug target for mCRPC.
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- 2018
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7. Inhibition of O-GlcNAcase leads to elevation of O-GlcNAc tau and reduction of tauopathy and cerebrospinal fluid tau in rTg4510 mice
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Nicholas B. Hastings, Xiaohai Wang, Lixin Song, Brent D. Butts, Diane Grotz, Richard Hargreaves, J. Fred Hess, Kwok-Lam Karen Hong, Cathy Ruey-Ruey Huang, Lynn Hyde, Maureen Laverty, Julie Lee, Diane Levitan, Sherry X. Lu, Maureen Maguire, Veeravan Mahadomrongkul, Ernest J. McEachern, Xuesong Ouyang, Thomas W. Rosahl, Harold Selnick, Michaela Stanton, Giuseppe Terracina, David J. Vocadlo, Ganfeng Wang, Joseph L. Duffy, Eric M. Parker, and Lili Zhang
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Tau ,OGA ,O-GlcNAc ,Alzheimer’s disease ,Tauopathy ,Neurodegeneration ,Neurology. Diseases of the nervous system ,RC346-429 ,Geriatrics ,RC952-954.6 - Abstract
Abstract Background Hyperphosphorylation of microtubule-associated protein tau is a distinct feature of neurofibrillary tangles (NFTs) that are the hallmark of neurodegenerative tauopathies. O-GlcNAcylation is a lesser known post-translational modification of tau that involves the addition of N-acetylglucosamine onto serine and threonine residues. Inhibition of O-GlcNAcase (OGA), the enzyme responsible for the removal of O-GlcNAc modification, has been shown to reduce tau pathology in several transgenic models. Clarifying the underlying mechanism by which OGA inhibition leads to the reduction of pathological tau and identifying translatable measures to guide human dosing and efficacy determination would significantly facilitate the clinical development of OGA inhibitors for the treatment of tauopathies. Methods Genetic and pharmacological approaches are used to evaluate the pharmacodynamic response of OGA inhibition. A panel of quantitative biochemical assays is established to assess the effect of OGA inhibition on pathological tau reduction. A “click” chemistry labeling method is developed for the detection of O-GlcNAcylated tau. Results Substantial (>80%) OGA inhibition is required to observe a measurable increase in O-GlcNAcylated proteins in the brain. Sustained and substantial OGA inhibition via chronic treatment with Thiamet G leads to a significant reduction of aggregated tau and several phosphorylated tau species in the insoluble fraction of rTg4510 mouse brain and total tau in cerebrospinal fluid (CSF). O-GlcNAcylated tau is elevated by Thiamet G treatment and is found primarily in the soluble 55 kD tau species, but not in the insoluble 64 kD tau species thought as the pathological entity. Conclusion The present study demonstrates that chronic inhibition of OGA reduces pathological tau in the brain and total tau in the CSF of rTg4510 mice, most likely by directly increasing O-GlcNAcylation of tau and thereby maintaining tau in the soluble, non-toxic form by reducing tau aggregation and the accompanying panoply of deleterious post-translational modifications. These results clarify some conflicting observations regarding the effects and mechanism of OGA inhibition on tau pathology, provide pharmacodynamic tools to guide human dosing and identify CSF total tau as a potential translational biomarker. Therefore, this study provides additional support to develop OGA inhibitors as a treatment for Alzheimer’s disease and other neurodegenerative tauopathies.
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- 2017
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8. Early intervention of tau pathology prevents behavioral changes in the rTg4510 mouse model of tauopathy.
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Xiaohai Wang, Karen Smith, Michelle Pearson, Anna Hughes, Mali L Cosden, Jacob Marcus, J Fred Hess, Mary J Savage, Thomas Rosahl, Sean M Smith, Joel B Schachter, and Jason M Uslaner
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Medicine ,Science - Abstract
Although tau pathology, behavioral deficits, and neuronal loss are observed in patients with tauopathies, the relationship between these endpoints has not been clearly established. Here we found that rTg4510 mice, which overexpress human mutant tau in the forebrain, develop progressive age-dependent increases in locomotor activity (LMA), which correlates with neurofibrillary tangle (NFT) pathology, hyperphosphorylated tau levels, and brain atrophy. To further clarify the relationship between these endpoints, we treated the rTg4510 mice with either doxycycline to reduce mutant tau expression or an O-GlcNAcase inhibitor Thiamet G, which has been shown to ameliorate tau pathology in animal models. We found that both doxycycline and Thiamet G treatments starting at 2 months of age prevented the progression of hyperactivity, slowed brain atrophy, and reduced brain hyperphosphorylated tau. In contrast, initiating doxycycline treatment at 4 months reduced neither brain hyperphosphorylated tau nor hyperactivity, further confirming the relationship between these measures. Collectively, our results demonstrate a unique behavioral phenotype in the rTg4510 mouse model of tauopathy that strongly correlates with disease progression, and that early interventions which reduce tau pathology ameliorate the progression of the locomotor dysfunction. These findings suggest that better understanding the relationship between locomotor deficits and tau pathology in the rTg4510 model may improve our understanding of the mechanisms underlying behavioral disturbances in patients with tauopathies.
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- 2018
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9. fMRI study of the role of glutamate NMDA receptor in the olfactory processing in monkeys.
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Fuqiang Zhao, Marie A Holahan, Xiaohai Wang, Jason M Uslaner, Andrea K Houghton, Jeffrey L Evelhoch, Christopher T Winkelmann, and Catherine D G Hines
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Medicine ,Science - Abstract
Studies in rodents show that olfactory processing in the principal neurons of olfactory bulb (OB) and piriform cortex (PC) is controlled by local inhibitory interneurons, and glutamate NMDA receptor plays a role in this inhibitory control. It is not clear if findings from studies in rodents translate to olfactory processing in nonhuman primates (NHPs). In this study, the effect of the glutamate NMDA receptor antagonist MK801 on odorant-induced olfactory responses in the OB and PC of anesthetized NHPs (rhesus monkeys) was investigated by cerebral blood volume (CBV) fMRI. Isoamyl-acetate was used as the odor stimulant. For each NHP, sixty fMRI measurements were made during a 4-h period, with each 4-min measurement consisting of a 1-min baseline period, a 1-min odor stimulation period, and a 2-min recovery period. MK801 (0.3 mg/kg) was intravenously delivered 1 hour after starting fMRI. Before MK801 injection, olfactory fMRI activations were observed only in the OB, not in the PC. After MK801 injection, olfactory fMRI activations in the OB increased, and robust olfactory fMRI activations were observed in the PC. The data indicate that MK801 enhances the olfactory responses in both the OB and PC. The enhancement effects of MK801 are most likely from its blockage of NMDA receptors on local inhibitory interneurons and the attenuation of the inhibition onto principal neurons. This study suggests that the mechanism of local inhibitory control of principal neurons in the OB and PC derived from studies in rodents translates to NHPs.
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- 2018
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10. Optimal Scheduling of Integrated Energy Systems with Combined Heat and Power Generation, Photovoltaic and Energy Storage Considering Battery Lifetime Loss
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Yongli Wang, Haiyang Yu, Mingyue Yong, Yujing Huang, Fuli Zhang, and Xiaohai Wang
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integrated energy system ,optimal scheduling ,differential evolution ,life quantification ,Technology - Abstract
Integrated energy systems (IESs) are considered a trending solution for the energy crisis and environmental problems. However, the diversity of energy sources and the complexity of the IES have brought challenges to the economic operation of IESs. Aiming at achieving optimal scheduling of components, an IES operation optimization model including photovoltaic, combined heat and power generation system (CHP) and battery energy storage is developed in this paper. The goal of the optimization model is to minimize the operation cost under the system constraints. For the optimization process, an optimization principle is conducted, which achieves maximized utilization of photovoltaic by adjusting the controllable units such as energy storage and gas turbine, as well as taking into account the battery lifetime loss. In addition, an integrated energy system project is taken as a research case to validate the effectiveness of the model via the improved differential evolution algorithm (IDEA). The comparison between IDEA and a traditional differential evolution algorithm shows that IDEA could find the optimal solution faster, owing to the double variation differential strategy. The simulation results in three different battery states which show that the battery lifetime loss is an inevitable factor in the optimization model, and the optimized operation cost in 2016 drastically decreased compared with actual operation data.
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- 2018
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11. SUMOylation represses Nanog expression via modulating transcription factors Oct4 and Sox2.
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Yongyan Wu, Zekun Guo, Haibo Wu, Xiaohai Wang, Lixia Yang, Xiaoyan Shi, Juan Du, Bo Tang, Wenzhong Li, Liping Yang, and Yong Zhang
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Medicine ,Science - Abstract
Nanog is a pivotal transcription factor in embryonic stem (ES) cells and is essential for maintaining the pluripotency and self-renewal of ES cells. SUMOylation has been proved to regulate several stem cell markers' function, such as Oct4 and Sox2. Nanog is strictly regulated by Oct4/Sox2 heterodimer. However, the direct effects of SUMOylation on Nanog expression remain unclear. In this study, we reported that SUMOylation repressed Nanog expression. Depletion of Sumo1 or its conjugating enzyme Ubc9 increased the expression of Nanog, while high SUMOylation reduced its expression. Interestingly, we found that SUMOylation of Oct4 and Sox2 regulated Nanog in an opposing manner. SUMOylation of Oct4 enhanced Nanog expression, while SUMOylated Sox2 inhibited its expression. Moreover, SUMOylation of Oct4 by Pias2 or Sox2 by Pias3 impaired the interaction between Oct4 and Sox2. Taken together, these results indicate that SUMOylation has a negative effect on Nanog expression and provides new insights into the mechanism of SUMO modification involved in ES cells regulation.
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- 2012
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12. Autoencoder-based method to assess bridge health monitoring data quality.
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Bowen Xiao, Jin Di, Jie Wang, Guanliang Wu, Jiapeng Shi, Xiaohai Wang, and Jiuhong Fan
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- 2024
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13. Consideration of reliability and economy to Capacity Configuration of energy storage system: Case Study of a large scale wind power plant in the Northwest China
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Yongli, Wang, Haiyang, Yu, Xiaohai, Wang, Fuli, Zhang, and Yujing, Huang
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- 2018
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14. Transurethral thulium laser enucleation versus resection of the prostate for treating benign prostatic hyperplasia: a retrospective study
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Yuan, Ruan, Boyu, Yang, Fujun, Zhao, Chengyi, Jiang, Yifeng, Jing, Xiaohai, Wang, Di, Cui, Shujie, Xia, and Bangmin, Han
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- 2019
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15. fMRI study of the role of glutamate NMDA receptor in the olfactory adaptation in rats: Insights into cellular and molecular mechanisms of olfactory adaptation.
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Fuqiang Zhao, Xiaohai Wang, Hatim A. Zariwala, Jason M. Uslaner, Andrea K. Houghton, Jeffrey L. Evelhoch, Eric Hostetler, Christopher T. Winkelmann, and Catherine D. G. Hines
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- 2017
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16. fMRI study of olfaction in the olfactory bulb and high olfactory structures of rats: Insight into their roles in habituation.
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Fuqiang Zhao, Xiaohai Wang, Hatim A. Zariwala, Jason M. Uslaner, Andrea K. Houghton, Jeffrey L. Evelhoch, Donald S. Williams, and Christopher T. Winkelmann
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- 2016
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17. Adaptive priority-based cache replacement and prediction-based cache prefetching in edge computing environment.
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Chunlin Li 0001, Mingyang Song, Shaofeng Du, Xiaohai Wang, Min Zhang, and Youlong Luo
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- 2020
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18. Rapamycin and Low-dose IL-2 Mediate an Immunosuppressive Microenvironment to Inhibit Benign Prostatic Hyperplasia.
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Tianyu Cao, Feng Xie, Youwei Shi, Junhao Xu, Yi Liu, Di Cui, Fang Zhang, Lihui Lin, Weize Li, Yanting Gao, Yuan Ruan, Xiaohai Wang, Yiping Zhu, Bangmin Han, Shujie Xia, Wenhuan Guo, Bin Li, and Yifeng Jing
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- 2023
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19. Impact of energy storage system on the point of common coupling of the distribution network containing photovoltaic plant.
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Hua Li, Xiaohai Wang, Wenyi Li, Baiqing Yin, and Yu Xu
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ENERGY storage , *PHOTOVOLTAIC power generation , *PHOTOVOLTAIC power systems , *SOLAR energy , *POWER resources - Abstract
This paper attempts to disclose the effects of the access of energy storage system on the fluctuations of power and voltage at the point of common coupling (PCC) in distribution networks containing photovoltaic (PV) plants. For this purpose, a photovoltaic/energy storage (PV/ES) power generation model was established and the variations in PCC power and voltage before and after the access of the energy storage system were simulated at different temperatures, access positions and capacities. Besides, the decrease in PCC voltage fluctuations was quantified according to the standard deviation of effective voltage. The simulation results reveal that the access of the energy storage system can effectively suppress the PCC voltage and power fluctuations caused by ambient temperature variation, and thus improve the PCC power quality; the same energy storage system has slightly different suppression effects on PCC voltage fluctuations depending on the access position of the PV plant and PV/ES system; the PCC voltage resistance grows significantly with the capacity expansion of the energy storage system. The research findings shed new light on the access of energy storage system to distribution networks containing PV plants. [ABSTRACT FROM AUTHOR]
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- 2018
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20. Inhibition of O-GlcNAcase leads to elevation of O-GlcNAc tau and reduction of tauopathy and cerebrospinal fluid tau in rTg4510 mice.
- Author
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Hastings, Nicholas B., Xiaohai Wang, Lixin Song, Butts, Brent D., Grotz, Diane, Hargreaves, Richard, Hess, J. Fred, Kwok-Lam Karen Hong, Ruey-Ruey Huang, Cathy, Hyde, Lynn, Laverty, Maureen, Lee, Julie, Levitan, Diane, Lu, Sherry X., Maguire, Maureen, Mahadomrongkul, Veeravan, McEachern, Ernest J., Xuesong Ouyang, Rosahl, Thomas W., and Selnick, Harold
- Subjects
CEREBROSPINAL fluid ,MICROTUBULE-associated proteins ,NEUROFIBRILLARY tangles ,PATHOLOGY ,NEURODEGENERATION - Abstract
Background: Hyperphosphorylation of microtubule-associated protein tau is a distinct feature of neurofibrillary tangles (NFTs) that are the hallmark of neurodegenerative tauopathies. O-GlcNAcylation is a lesser known posttranslational modification of tau that involves the addition of N-acetylglucosamine onto serine and threonine residues. Inhibition of O-GlcNAcase (OGA), the enzyme responsible for the removal of O-GlcNAc modification, has been shown to reduce tau pathology in several transgenic models. Clarifying the underlying mechanism by which OGA inhibition leads to the reduction of pathological tau and identifying translatable measures to guide human dosing and efficacy determination would significantly facilitate the clinical development of OGA inhibitors for the treatment of tauopathies. Methods: Genetic and pharmacological approaches are used to evaluate the pharmacodynamic response of OGA inhibition. A panel of quantitative biochemical assays is established to assess the effect of OGA inhibition on pathological tau reduction. A "click" chemistry labeling method is developed for the detection of O-GlcNAcylated tau. Results: Substantial (>80%) OGA inhibition is required to observe a measurable increase in O-GlcNAcylated proteins in the brain. Sustained and substantial OGA inhibition via chronic treatment with Thiamet G leads to a significant reduction of aggregated tau and several phosphorylated tau species in the insoluble fraction of rTg4510 mouse brain and total tau in cerebrospinal fluid (CSF). O-GlcNAcylated tau is elevated by Thiamet G treatment and is found primarily in the soluble 55 kD tau species, but not in the insoluble 64 kD tau species thought as the pathological entity. Conclusion: The present study demonstrates that chronic inhibition of OGA reduces pathological tau in the brain and total tau in the CSF of rTg4510 mice, most likely by directly increasing O-GlcNAcylation of tau and thereby maintaining tau in the soluble, non-toxic form by reducing tau aggregation and the accompanying panoply of deleterious post-translational modifications. These results clarify some conflicting observations regarding the effects and mechanism of OGA inhibition on tau pathology, provide pharmacodynamic tools to guide human dosing and identify CSF total tau as a potential translational biomarker. Therefore, this study provides additional support to develop OGA inhibitors as a treatment for Alzheimer's disease and other neurodegenerative tauopathies. [ABSTRACT FROM AUTHOR]
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- 2017
- Full Text
- View/download PDF
21. Analysis of tau post-translational modifications in rTg4510 mice, a model of tau pathology.
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Lixin Song, Lu, Sherry X., Xuesong Ouyang, Melchor, Jerry, Lee, Julie, Terracina, Giuseppe, Xiaohai Wang, Hyde, Lynn, Hess, J. Fred, Parker, Eric M., and Zhang, Lili
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MICROTUBULE-associated proteins ,ALZHEIMER'S disease research ,TAU proteins ,IMMUNOASSAY ,DEMENTIA ,UBIQUITINATION ,ACETYLATION - Abstract
Background: Microtubule associated protein tau is the major component of the neurofibrillary tangles (NFTs) found in the brains of patients with Alzheimer's disease and several other neurodegenerative diseases. Tau mutations are associated with frontotemperal dementia with parkinsonism on chromosome 17 (FTDP-17). rTg4510 mice overexpress human tau carrying the P301L FTDP-17 mutation and develop robust NFT-like pathology at 4-5 months of age. The current study is aimed at characterizing the rTg4510 mice to better understand the genesis of tau pathology and to better enable the use of this model in drug discovery efforts targeting tau pathology. Results: Using a panel of immunoassays, we analyzed the age-dependent formation of pathological tau in rTg4510 mice and our data revealed a steady age-dependent accumulation of pathological tau in the insoluble fraction of brain homogenates. The pathological tau was associated with multiple post-translational modifications including aggregation, phosphorylation at a wide variety of sites, acetylation, ubiquitination and nitration. The change of most tau species reached statistical significance at the age of 16 weeks. There was a strong correlation between the different post-translationally modified tau species in this heterogeneous pool of pathological tau. Total tau in the cerebrospinal fluid (CSF) displayed a multiphasic temporal profile distinct from the steady accumulation of pathological tau in the brain. Female rTg4510 mice displayed significantly more aggressive accumulation of pathological tau in the brain and elevation of total tau in CSF than their male littermates. Conclusion: The immunoassays described here were used to generate the most comprehensive description of the changes in various tau species across the lifespan of the rTg4510 mouse model. The data indicate that development of tauopathy in rTg4510 mice involves the accumulation of a pool of pathological tau that carries multiple posttranslational modifications, a process that can be detected well before the histological detection of NFTs. Therapeutic treatment targeting tau should therefore aim to reduce all tau species associated with the pathological tau pool rather than reduce specific post-translational modifications. There is still much to learn about CSF tau in physiological and pathological processes in order to use it as a translational biomarker in drug discovery. [ABSTRACT FROM AUTHOR]
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- 2015
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22. DRUG DISCOVERY Orexin Receptor Antagonists Differ from Standard Sleep Drugs by Promoting Sleep at Doses That Do Not Disrupt Cognition.
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Uslaner, Jason M., Tye, Spencer J., Eddins, Donnie M., Xiaohai Wang, Fox, Steven V., Savitz, Alan T., Binns, Jacquelyn, Cannon, Christopher E., Garson, Susan L., Lihang Yao, Hodgson, Robert, Stevens, Joanne, Bowlby, Mark R., Tannenbaum, Pamela L., Brunner, Joseph, Mcdonald, Terrence P., Gotter, Anthony L., Kuduk, Scott D., Coleman, Paul J., and Winrow, Christopher J.
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- 2013
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23. Increased Infiltrated Macrophages in Benign Prostatic Hyperplasia (BPH): ROLE OF STROMAL ANDROGEN RECEPTOR IN MACROPHAGE-INDUCED PROSTATE STROMAL CELL PROLIFERATION.
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Xiaohai Wang, Wen-Jye Lin, Kouji Izumi, Qi Jiang, Kuo-Pao Lai, Defeng Xu, Lei-Ya Fang, Tianjing Lu, Lei Li, Shujie Xia, and Chawnshang Chang
- Subjects
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MACROPHAGES , *BENIGN prostatic hyperplasia , *STROMAL cells , *ANDROGEN receptors , *GROWTH factors , *CELLULAR mechanics , *CLINICAL trials - Abstract
Infiltrated macrophages may play important roles in the development and progression of benign prostatic hyperplasia (BPH), but the underlying mechanisms remain largely unknown. We found increased macrophages infiltration in human and mouse BPH tissues. By establishing a co-culture transwell system, we found increased migration of macrophages and proliferation of prostate stromal cells during co-culture. Importantly, stromal androgen receptor (AR) could enhance the migration of macrophages and macrophage-mediated stromal cell proliferation. We identified CCL3 as an AR downstream player, and found CCL3 levels were notably increased in human and mouse BPH prostates. Ablation of prostate stromal AR in a mouse BPH model significantly reduced CCL3 expression levels in prostates. Consistently, targeting AR via an AR degradation enhancer, ASC-J9®, or neutralization of CCL3 with an antibody, resulted in suppression of macrophage migration and prostate stromal cell growth. Our study provides mechanistic insights on the regulation of prostate stromal cells by macrophages via stromal AR/CCL3 signaling pathways, which could potentially allow the development of therapeutic approaches for battling BPH with persistent inflammation. [ABSTRACT FROM AUTHOR]
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- 2012
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24. Adenosine is crucial for deep brain stimulation–mediated attenuation of tremor.
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Bekar, Lane, Libionka, Witold, Guo-Feng Tian, Qiwu Xu, Torres, Arnulfo, Xiaohai Wang, Lovatt, Ditte, Williams, Erika, Takano, Takahiro, Schnermann, Jurgen, Bakos, Robert, and Nedergaard, Maiken
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ADENOSINES ,BRAIN stimulation ,TREMOR ,CAFFEINE ,THALAMUS - Abstract
Deep brain stimulation (DBS) is a widely used neurosurgical approach to treating tremor and other movement disorders. In addition, the use of DBS in a number of psychiatric diseases, including obsessive-compulsive disorders and depression, is currently being tested. Despite the rapid increase in the number of individuals with surgically implanted stimulation electrodes, the cellular pathways involved in mediating the effects of DBS remain unknown. Here we show that DBS is associated with a marked increase in the release of ATP, resulting in accumulation of its catabolic product, adenosine. Adenosine A1 receptor activation depresses excitatory transmission in the thalamus and reduces both tremor- and DBS-induced side effects. Intrathalamic infusion of A1 receptor agonists directly reduces tremor, whereas adenosine A1 receptor–null mice show involuntary movements and seizure at stimulation intensities below the therapeutic level. Furthermore, our data indicate that endogenous adenosine mechanisms are active in tremor, thus supporting the clinical notion that caffeine, a nonselective adenosine receptor antagonist, can trigger or exacerbate essential tremor. Our findings suggest that nonsynaptic mechanisms involving the activation of A1 receptors suppress tremor activity and limit stimulation-induced side effects, thereby providing a new pharmacological target to replace or improve the efficacy of DBS. [ABSTRACT FROM AUTHOR]
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- 2008
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25. Astrocytic Ca2+ signaling evoked by sensory stimulation in vivo.
- Author
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Xiaohai Wang, Nanhong Lou, Qiwu Xu, Guo-Feng Tian, Wei Guo Peng, Xiaoning Han, Jian Kang, Takano, Takahiro, and Nedergaard, Maiken
- Subjects
- *
ASTROCYTES , *BRAIN , *CELLS , *MICE , *ASTROCYTOMAS , *SENSORY stimulation - Abstract
Although astrocytes are the most abundant cell type in the brain, evidence for their activation during physiological sensory activity is lacking. Here we show that whisker stimulation evokes increases in astrocytic cytosolic calcium (Ca2+) within the barrel cortex of adult mice. Increases in astrocytic Ca2+ were a function of the frequency of stimulation, occurred within several seconds and were inhibited by metabotropic glutamate receptor antagonists. To distinguish between synaptic input and output, local synaptic activity in cortical layer 2 was silenced by iontophoresis of AMPA and NMDA receptor antagonists. The antagonists did not reduce astrocytic Ca2+ responses despite a marked reduction in excitatory postsynaptic currents in response to whisker stimulation. These findings indicate that astrocytes respond to synaptic input, by means of spillover or ectopic release of glutamate, and that increases in astrocytic Ca2+ occur independently of postsynaptic excitatory activity. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
26. An astrocytic basis of epilepsy.
- Author
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Guo-Feng Tian, Hooman Azmi, Takano, Takahiro, Qiwu Xu, Weiguo Peng, Lin, Jane, Oberheim, NancyAnn, Nanhong Lou, Xiaohai Wang, Zielke, H Ronald, Jian Kang, and Nedergaard, Maiken
- Subjects
EPILEPSY ,BRAIN diseases ,SEIZURES (Medicine) ,SPASMS ,ASTROCYTES ,NEURONS ,TETRODOTOXIN ,NEUROTOXIC agents - Abstract
Hypersynchronous neuronal firing is a hallmark of epilepsy, but the mechanisms underlying simultaneous activation of multiple neurons remains unknown. Epileptic discharges are in part initiated by a local depolarization shift that drives groups of neurons into synchronous bursting. In an attempt to define the cellular basis for hypersynchronous bursting activity, we studied the occurrence of paroxysmal depolarization shifts after suppressing synaptic activity using tetrodotoxin (TTX) and voltage-gated Ca
2+ channel blockers. Here we report that paroxysmal depolarization shifts can be initiated by release of glutamate from extrasynaptic sources or by photolysis of caged Ca2+ in astrocytes. Two-photon imaging of live exposed cortex showed that several antiepileptic agents, including valproate, gabapentin and phenytoin, reduced the ability of astrocytes to transmit Ca2+ signaling. Our results show an unanticipated key role for astrocytes in seizure activity. As such, these findings identify astrocytes as a proximal target for the treatment of epileptic disorders. [ABSTRACT FROM AUTHOR]- Published
- 2005
- Full Text
- View/download PDF
27. P2X7 receptor inhibition improves recovery after spinal cord injury.
- Author
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Xiaohai Wang, Arcuino, Gregory, Takano, Takahiro, Lin, Jane, Wei Guo Peng, Pinglan Wan, Pingjia Li, Qiwu Xu, Qing Song Liu, Goldman, Steven A., and Nedergaard, Maiken
- Subjects
- *
SPINAL cord injuries , *ADENOSINE triphosphate , *NEURONS , *PURINERGIC receptors , *CELL death , *NEURODEGENERATION - Abstract
Secondary injury exacerbates the extent of spinal cord insults, yet the mechanistic basis of this phenomenon has largely been unexplored. Here we report that broad regions of the peritraumatic zone are characterized by a sustained process of pathologic, high ATP release. Spinal cord neurons expressed P2X7 purine receptors (P2X7R), and exposure to ATP led to high-frequency spiking, irreversible increases in cytosolic calcium and cell death. To assess the potential effect of P2X7R blockade in ameliorating acute spinal cord injury (SCI), we delivered P2X7R antagonists OxATP or PPADS to rats after acute impact injury. We found that both OxATP and PPADS significantly improved functional recovery and diminished cell death in the peritraumatic zone. These observations demonstrate that SCI is associated with prolonged purinergic receptor activation, which results in excitotoxicity-based neuronal degeneration. P2X7R antagonists inhibit this process, reducing both the histological extent and functional sequelae of acute SCI. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
28. Connexin Mediates Gap Junction-Independent Resistance to Cellular Injury.
- Author
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Lin, Jane H.-C., Yang, Jay, Shujun Liu, Takano, Takahiro, Xiaohai Wang, Qun Gao, Willecke, Klaus, and Nedergaard, Maiken
- Subjects
CELL death ,GAP junctions (Cell biology) ,CONNEXINS ,CELL junctions ,DEATH (Biology) - Abstract
Presents a study which investigated the role of gap junctions in cell death. Composition of gap junctions; Assessment of the effect of nonfunctional connexin mutations on cell resistance; Examination of the role of intercellular coupling in injury resistance.
- Published
- 2003
- Full Text
- View/download PDF
29. Study and application of finite time convergence ADRC with dead zone and anti-saturation disturbance compensation.
- Author
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Yuanqing Wang, Qi Wang, Jian Yuan, Liang An, Juan Su, and Xiaohai Wang
- Published
- 2019
- Full Text
- View/download PDF
30. A hybrid harmony search with arithmetic crossover operation for economic dispatch.
- Author
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Qun Niu, Hongyun Zhang, Xiaohai Wang, Kang Li, and Irwin, George W.
- Subjects
- *
SEARCH algorithms , *ECONOMIC models , *PROBLEM solving , *NONCONVEX programming , *POWER transmission , *GLOBAL optimization - Abstract
Economic dispatch (ED) problems often exhibit non-linear, non-convex characteristics due to the valve point effects. Further, various constraints and factors, such as prohibited operation zones, ramp rate limits and security constraints imposed by the generating units, and power loss in transmission make it even more challenging to obtain the global optimum using conventional mathematical methods. Meta-heuristic approaches are capable of solving non-linear, non-continuous and non-convex problems effectively as they impose no requirements on the optimization problems. However, most methods reported so far mainly focus on a specific type of ED problems, such as static or dynamic ED problems. This paper proposes a hybrid harmony search with arithmetic crossover operation, namely ACHS, for solving five different types of ED problems, including static ED with valve point effects, ED with prohibited operating zones, ED considering multiple fuel cells, combined heat and power ED, and dynamic ED. In this proposed ACHS, the global best information and arithmetic crossover are used to update the newly generated solution and speed up the convergence, which contributes to the algorithm exploitation capability. To balance the exploitation and exploration capabilities, the opposition based learning (OBL) strategy is employed to enhance the diversity of solutions. Further, four commonly used crossover operators are also investigated, and the arithmetic crossover shows its efficiency than the others when they are incorporated into HS. To make a comprehensive study on its scalability, ACHS is first tested on a group of benchmark functions with a 100 dimensions and compared with several state-of-the-art methods. Then it is used to solve seven different ED cases and compared with the results reported in literatures. All the results confirm the superiority of the ACHS for different optimization problems. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
31. Detecting tau in serum of transgenic animal models after tau immunotherapy treatment.
- Author
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d'Abramo, Cristina, Acker, Christopher M., Schachter, Joel B., Terracina, Giuseppe, Xiaohai Wang, Forest, Stefanie K., and Davies, Peter
- Subjects
- *
IMMUNOTHERAPY , *TAU protein structure , *ENZYME-linked immunosorbent assay , *SERUM , *TRANSGENIC animals , *LABORATORY mice - Abstract
In the attempt to elucidate if the "peripheral sink hypothesis" could be a potential mechanism of action for tau removal in passive immunotherapy experiments, we have examined tau levels in serum of chronically injected JNPL3 and Tg4510 transgenic animals. Measurement of tau in serum of mice treated with tau antibodies is challenging because of the antibody interference in sandwich enzyme-linked immunosorbent assays. To address this issue, we have developed a heat-treatment protocol at acidic pH to remove interfering molecules from serum, with excellent recovery of tau. The present data show that pan-tau and conformational antibodies do increase tau in mouse sera. However, these concentrations in serum do not consistently correlate with reductions of tau pathology in brain, suggesting that large elevations of tau species measured in serum are not predictive of efficacy. Here, we describe a reliable method to detect tau in serum of transgenic animals that have undergone tau immunotherapy. Levels of tau in human serum are less than the sensitivity of current assays, although artifactual signals are common. The method may be useful in similarly treated humans, a situation in which false positive signals are likely. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
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