48 results on '"Yi Ping, Li"'
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2. Comparing the effects of two different progesterone vaginal gels, Progeson™ and Crinone™, from pharmacokinetics study to clinical applications in patients undergone fresh embryo transfer and frozen-thawed embryo transfer via natural cycle endometrial preparation protocol
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Cheng-Wei Yu, Wei-Jiun Li, Wen-Chi Hsieh, Li-Shan Chen, and Yi-Ping Li
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Obstetrics and Gynecology - Published
- 2023
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3. Runt-related transcription factor 1 is required for murine osteoblast differentiation and bone formation
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Yiping Wang, Jing Xie, Yi-Ping Li, Jinjin Wu, Hou-De Zhou, Jun Tang, Wei Chen, Xuedong Zhou, and Chen-Yi Tang
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Male ,musculoskeletal diseases ,0301 basic medicine ,Activating Transcription Factor 4 ,Biochemistry ,Mice ,03 medical and health sciences ,Osteogenesis ,Osteoclast ,hemic and lymphatic diseases ,medicine ,Animals ,Molecular Biology ,Transcription factor ,Mice, Knockout ,Osteoblasts ,030102 biochemistry & molecular biology ,biology ,ATF4 ,Cell Differentiation ,Osteoblast ,Cell Biology ,Cell biology ,RUNX2 ,030104 developmental biology ,medicine.anatomical_structure ,Core Binding Factor Alpha 2 Subunit ,embryonic structures ,Osteocalcin ,biology.protein ,Osteoporosis ,Female ,Cortical bone - Abstract
Despite years of research investigating osteoblast differentiation, the mechanisms by which transcription factors regulate osteoblast maturation, bone formation, and bone homeostasis is still unclear. It has been reported that runt-related transcription factor 1 (Runx1) is expressed in osteoblast progenitors, pre-osteoblasts, and mature osteoblasts; yet, surprisingly, the exact function of RUNX1 in osteoblast maturation and bone formation remains unknown. Here, we generated and characterized a pre-osteoblast and differentiating chondrocyte-specific Runx1 conditional knockout mouse model to study RUNX1's function in bone formation. Runx1 ablation in osteoblast precursors and differentiating chondrocytes via osterix-Cre (Osx-Cre) resulted in an osteoporotic phenotype and decreased bone density in the long bones and skulls of Runx1(f/f)Osx-Cre mice compared with Runx1(f/f) and Osx-Cre mice. RUNX1 deficiency reduced the expression of SRY-box transcription factor 9 (SOX9), Indian hedgehog signaling molecule (IHH), Patched (PTC), and cyclin D1 in the growth plate, and also reduced the expression of osteocalcin (OCN), OSX, activating transcription factor 4 (ATF4), and RUNX2 in osteoblasts. ChIP assays and promoter activity mapping revealed that RUNX1 directly associates with the Runx2 gene promoter and up-regulates Runx2 expression. Furthermore, the ChIP data also showed that RUNX1 associates with the Ocn promoter. In conclusion, RUNX1 up-regulates the expression of Runx2 and multiple bone-specific genes, and plays an indispensable role in bone formation and homeostasis in both trabecular and cortical bone. We propose that stimulating Runx1 activity may be useful in therapeutic approaches for managing some bone diseases such as osteoporosis.
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- 2020
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4. Biomineralization and AHLs-guided quorum sensing enhanced phosphorus recovery in the alternating aerobic/anaerobic biofilm system under metal ion stress
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Hao, Zhang, Shuang-Shuang, Zhang, Wei, Zhang, Liang, Zhu, Yi-Ping, Li, and Yang, Pan
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Biomineralization ,Environmental Engineering ,Polyphosphates ,Metals ,Biofilms ,Quorum Sensing ,Phosphorus ,Anaerobiosis ,General Medicine ,Acyl-Butyrolactones ,Management, Monitoring, Policy and Law ,Waste Management and Disposal - Abstract
The alternating aerobic/anaerobic biofilm system had been applied for phosphorus (P) enrichment and recovery because of the advantage of low energy consumption and high efficiency. The metal ions and N-acyl-L-homoserine lactones (AHLs) in system were studied to better clarify the mechanism of P uptake/release under metal ion stress. The results indicated that the increase of metal ions stimulated the release of AHLs, and AHLs-guided quorum sensing (QS) enhanced P uptake. Moreover, biomineralization could stimulate the increase of P content in biofilm (P
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- 2023
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5. Recovering phosphorus as vivianite using an alternating aerobic/anaerobic biofilm and fluidized bed crystallization coupled system
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Hao Zhang, Wei Zhang, Liang Zhu, Yi-Ping Li, Yang Pan, Wu-Cheng Ma, and Ze Zong
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Process Chemistry and Technology ,Safety, Risk, Reliability and Quality ,Waste Management and Disposal ,Biotechnology - Published
- 2022
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6. Mother-to-child transmission of HIV: An 11-year experience in a single center and HIV prevention effectiveness in Taiwan
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Wen Wei Hsu, Chia-Hui Lin, Jessica Kang, Shin-Yu Lin, Yi-Ping Li, Chung Ching Shih, Hong Nerng Ho, Yi Yun Tai, Kuan Ying Huang, and Ming Wei Lin
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Adult ,Pediatrics ,medicine.medical_specialty ,Mother to child transmission ,Taiwan ,Human immunodeficiency virus (HIV) ,HIV Infections ,medicine.disease_cause ,Single Center ,Antiviral Agents ,World health ,Pregnancy ,Global health ,medicine ,Humans ,Pregnancy Complications, Infectious ,Retrospective Studies ,lcsh:R5-920 ,Prevention effectiveness ,Transmission (medicine) ,business.industry ,Infant ,virus diseases ,General Medicine ,University hospital ,Infectious Disease Transmission, Vertical ,Female ,lcsh:Medicine (General) ,business - Abstract
Background: Mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV) has become an essential global health issue and its elimination is a crucial target. A prenatal “opt-out” HIV screening program was initiated in 2005 in Taiwan. In recent 3 years, approximate screening and MTCT rates were 99% and 2.27% (1/44), respectively. Here, we describe the clinical management of mothers infected with HIV and MTCT rate at National Taiwan University Hospital (NTUH), Taipei, Taiwan, in the years after the program was initiated. Methods: We retrospectively reviewed charts of pregnant women infected with HIV, who were managed at NTUH between January 2005 and December 2016. HIV infection status of 39 infants born to mothers infected with HIV was available. Results: Between 2005 and December 2016, 50 pregnant women infected with HIV, with 57 parities were managed at NTUH, and 57 live infants were born. We excluded 18 parities because of missing data. Maternal antiviral treatment was administered in 37 of 39 infants. Only one infant tested positive for an HIV antibody test at 18 months, but showed definitive HIV exclusion at 20 months after a series of tests without administration of antiviral treatment. MTCT rate was 0%. Conclusion: Successful implementation of available perinatal HIV intervention dramatically reduced vertical transmission rate of HIV. MTCT rate was 0% in NTUH after the program. However, as NTUH is an HIV referral center, additional efforts are needed to achieve the World Health Organization criteria of lowering the vertical transmission rate of HIV to
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- 2019
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7. Development of Cell Culture Infectious Hepatitis C Virus Genotype 1b Clones and 1b-Induced Angiogenesis and Cholesterol Disorders
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Lin Ma, Dade Rong, Haihe Wang, Yi-Ping Li, Qing Zhou, Yuanping Zhou, Yang Yang, Jiawei Hao, Guirong Rao, Chengyao Li, Jinqian Li, Zhenzhen Zhang, Liang Rong, and Fei Xiao
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Infectivity ,Sofosbuvir ,Hepatitis C virus ,Biology ,medicine.disease ,medicine.disease_cause ,Virology ,Virus ,Titer ,Cell culture ,Hepatocellular carcinoma ,Genotype ,medicine ,medicine.drug - Abstract
Globally, hepatitis C virus (HCV) genotype 1b is most prevalent, and its infection has been found to associate with a higher risk of hepatocellular carcinoma (HCC) than other genotype viruses. However, an efficient infectious HCV genotype 1b culture system is unavailable, which has largely hampered the study of this important genotype virus. In this study, by using a systematic approach combining adaptive mutations and infectious 1a TNcc sequences, we succeeded in culture adaption of two full-length 1b clones for the reference strain Con1 and a clinical isolate A6, and designated as Con1cc and A6cc, respectively. Con1cc and A6cc replicated efficiently in hepatoma Huh7.5.1 cells, released HCV infectivity titers of 104.1 and 103.72 focus forming units per milliliter, respectively, and maintained the engineered mutations after passages. Both viruses responded to sofosbuvir and velpatasvir in a dose-dependent manner. With culture infectious 1b clones, we characterized the transcriptomes of 1b Con1cc-infected cells. Con1cc infection activated angiogenesis and disturbed cholesterol homeostasis compared with uninfected cells. In conclusion, we have developed infectious clones for genotype 1b and shown a novel strategy for culture adaptation of HCV isolates by using a genetically close backbone sequence. Besides, this study provides transcriptional landscape of HCV 1b-infected hepatoma cells facilitating the study of genotype 1b infection. Funding Statement: This work was supported by the National Natural Science Foundation of China (No. 81971938 for Y.-P.L.; 81772923 for Y.Z.), The Innovation Research Team for Basic and Clinical Studies on Chronic Liver Diseases of 2018 High-Level Health Teams of Zhuhai (for Y.-P.L. and F.X.), National Key Basic Research Program of China (No. 2015CB554301 for Y.-P.L.), Entrepreneurial Talent Team Award of Guangdong Province (No. 2016ZT06S252 for Y.-P.L.). Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: The use of patient serum was approved by the Medical Ethics Committee at the Zhongshan School of Medicine, Sun Yat-sen University (No. 2014-072).
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- 2021
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8. Recovering phosphorus as struvite from the concentrated solution produced by the alternating aerobic/anaerobic biofilm system
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Hao Zhang, Wei Zhang, Liang Zhu, Yi-Ping Li, Lin Chen, Yang Pan, and Yuan-Zhuo Xu
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Process Chemistry and Technology ,Chemical Engineering (miscellaneous) ,Pollution ,Waste Management and Disposal - Published
- 2022
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9. Phosphorus recovery in the alternating aerobic/anaerobic biofilm system: Performance and mechanism
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Hao, Zhang, Shuang-Shuang, Zhang, Liang, Zhu, Yi-Ping, Li, and Lin, Chen
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Bioreactors ,Environmental Engineering ,Sewage ,Polyphosphates ,Biofilms ,Environmental Chemistry ,Phosphorus ,Anaerobiosis ,Pollution ,Waste Management and Disposal - Abstract
To balance the high phosphorus concentration in recirculated solution and the stability of biofilm system, this study explored the performance and mechanism of phosphorus uptake/release for recovering phosphorus from sewage when the phosphorus content in biofilm (P
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- 2022
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10. Recombinant hepatitis C virus genotype 5a infectious cell culture systems expressing minimal JFH1 NS5B sequences permit polymerase inhibitor studies
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Tanja B. Jensen, Santseharay Ramirez, Judith M. Gottwein, Daryl Humes, Jens Bukh, and Yi-Ping Li
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0301 basic medicine ,Virus Cultivation ,Genotype ,Sofosbuvir ,viruses ,Hepatitis C virus ,Cell Culture Techniques ,Drug Evaluation, Preclinical ,Clone (cell biology) ,Hepacivirus ,Viral Nonstructural Proteins ,medicine.disease_cause ,Antiviral Agents ,Virus ,Cell Line ,03 medical and health sciences ,chemistry.chemical_compound ,Virology ,medicine ,Humans ,NS5B ,Polymerase ,biology ,030104 developmental biology ,Viral replication ,chemistry ,Hepatocytes ,biology.protein ,medicine.drug - Abstract
The six major epidemiologically important hepatitis C virus (HCV) genotypes differ in global distribution and antiviral responses. Full-length infectious cell-culture adapted clones, the gold standard for HCV studies in vitro, are missing for genotypes 4 and 5. To address this challenge for genotype 5, we constructed a consensus full-length clone of strain SA13 (SA13fl), which was found non-viable in Huh7.5 cells. Step-wise adaptation of SA13fl-based recombinants, beginning with a virus encoding the NS5B-thumb domain and 3´UTR of JFH1 (SA13/JF372-X), resulted in a high-titer SA13 virus with only 41 JFH1-encoded NS5B-thumb residues (SA13/JF470-510cc); this required sixteen cell-culture adaptive substitutions within the SA13fl polyprotein and two 3´UTR-changes. SA13/JF372-X and SA13/JF470-510cc were equally sensitive to nucleoside polymerase inhibitors, including sofosbuvir, but showed differential sensitivity to inhibitors targeting the NS5B palm or thumb. SA13/JF470-510cc represents a model to elucidate the influence of HCV RNA elements on viral replication and map determinants of sensitivity to polymerase inhibitors.
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- 2018
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11. Bone resorption deficiency affects tooth root development in RANKL mutant mice due to attenuated IGF-1 signaling in radicular odontoblasts
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Yan Zhang, Hong Huang, Guochun Zhu, Wei Chen, Ji Ping, Jue Wang, and Yi-Ping Li
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Male ,musculoskeletal diseases ,0301 basic medicine ,Histology ,Physiology ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Cellular differentiation ,Odontoblast differentiation ,Mice, Transgenic ,Bone resorption ,Mice ,03 medical and health sciences ,0302 clinical medicine ,stomatognathic system ,medicine ,Animals ,Bone Resorption ,Insulin-Like Growth Factor I ,Tooth Root ,Mice, Knockout ,Odontoblasts ,biology ,Chemistry ,Growth factor ,RANK Ligand ,Osteoblast ,030206 dentistry ,Dentinogenesis ,Cell biology ,Mice, Inbred C57BL ,Epithelial root sheath ,030104 developmental biology ,Odontoblast ,medicine.anatomical_structure ,RANKL ,Mutation ,biology.protein ,Signal Transduction - Abstract
The tooth root is essential for normal tooth physiological function. Studies on mice with mutations or targeted gene deletions revealed that osteoclasts (OCs) play an important role in tooth root development. However, knowledge on the cellular and molecular mechanism underlying how OCs mediate root formation is limited. During bone formation, growth factors (e.g. Insulin-like growth factor-1, IGF-1) liberated from bone matrix by osteoclastic bone resorption stimulate osteoblast differentiation. Thus, we hypothesize that OC-osteoblast coupling may also apply to OC-odontoblast coupling; therefore OCs may have a direct impact on odontoblast differentiation through the release of growth factor(s) from bone matrix, and consequently regulate tooth root formation. To test this hypothesis, we used a receptor activator of NF-κB ligand (RANKL) knockout mouse model in which OC differentiation and function was entirely blocked. We found that molar root formation and tooth eruption were defective in RANKL-/- mice. Disrupted elongation and disorganization of Hertwig's epithelial root sheath (HERS) was observed in RANKL-/- mice. Reduced expression of nuclear factor I C (NFIC), osterix, and dentin sialoprotein, markers essential for radicular (root) odontogenic cell differentiation indicated that odontoblast differentiation was disrupted in RANKL deficient mice likely contributing to the defect in root formation. Moreover, down-regulation of IGF/AKT/mTOR activity in odontoblast indicated that IGF signaling transduction in odontoblasts of the mutant mice was impaired. Treating odontoblast cells in vitro with conditioned medium from RANKL-/- OCs cultured on bone slices resulted in inhibition of odontoblast differentiation. Moreover, depletion of IGF-1 in bone resorption-conditioned medium (BRCM) from wild-type (WT) OC significantly compromised the ability of WT osteoclastic BRCM to induce odontoblast differentiation while addition of IGF-1 into RANKL-/- osteoclastic BRCM rescued impaired odontoblast differentiation, confirming that root and eruption defect in RANKL deficiency mice may result from failure of releasing of IGF-1 from bone matrix through OC bone resorption. These results suggest that OCs are important for odontoblast differentiation and tooth root formation, possibly through IGF/AKT/mTOR signaling mediated by cell-bone matrix interaction. These findings provide significant insights into regulatory mechanism of tooth root development, and also lay the foundation for root regeneration studies.
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- 2018
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12. Novel genetically stable infectious clone for a Zika virus clinical isolate and identification of RNA elements essential for virus production
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Ping Zhang, Liang Rong, Ling Ma, Yiyi Chen, Xi Huang, Bolan Yu, De Wu, Yi-Ping Li, Zhenzhen Zhang, Mingxiao Chen, Hui Zhang, Ting Liu, and Xun Zhu
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0301 basic medicine ,Cancer Research ,DNA, Complementary ,Virus Cultivation ,Clone (cell biology) ,Genome, Viral ,Biology ,Virus Replication ,Virus ,Zika virus ,Mice ,03 medical and health sciences ,Plasmid ,Virology ,Complementary DNA ,Chlorocebus aethiops ,Escherichia coli ,Animals ,Humans ,Cloning, Molecular ,Promoter Regions, Genetic ,Vero Cells ,Infectivity ,Zika Virus Infection ,Zika Virus ,Viral Load ,biology.organism_classification ,Reverse Genetics ,Flavivirus ,030104 developmental biology ,Infectious Diseases ,A549 Cells ,Mutation ,Vero cell ,RNA, Viral - Abstract
Zika virus (ZIKV) is an Aedes mosquitoes-transmitted flavivirus, and its infection may cause severe neurological diseases. A genetically stable infectious clone is essential for ZIKV research, however the toxicity and instability of the viral cDNA in bacteria potentially due to its bacterial promoter activity are major challenges. Here, we constructed a full-length cDNA clone for isolate ZG01 by introducing non-coding changes T1865C/A1868G to reduce the bacterial promoter activity. Wild-type and recombinant ZG01 were highly attenuated in Vero cells, thus we serially passaged wild-type ZG01 through neonatal mice and Vero cells to generate high-titer virus, from which four mutations (4m, C2178T/G2913A/T4991C/T10561C) were identified. Addition of 4m greatly enhanced the infectivity, as ZG01_4m released ZIKV of 107.0-107.5 plaque-forming unit (PFU)/ml in infected Vero and A549 cells. ZG01_4m resembled the infectivity of high-titer ZG01 in vitro and in vivo. Notably, ZG01_4m plasmid was genetically stable after multiple rounds of transformation-purification in bacteria. Using ZG01_4m, we identified a potential RNA-RNA interaction between 5'UTR and 3'UTR and demonstrated that the nucleotides involved were essential for ZIKV production. The genetically stable ZG01 cDNA clone provides a reliable tool for the study of this important virus, and the strategy used here is feasible for the development of reverse genetics systems for other ZIKV isolates and related flaviviruses.
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- 2018
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13. Identification of Ascomycin against Zika virus infection through screening of natural product library
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Yi-Ping Li, Liang Zhou, Tiantian Wu, Wenfang Chen, Wei Yang, Jia Zhou, Tongling Chen, Xinhui Zhang, Xiaojing Chi, Xiuying Liu, Shengnan Pan, and Tianli Lin
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Hepatitis C virus ,Dengue virus ,Virus Replication ,medicine.disease_cause ,Antiviral Agents ,Tacrolimus ,Zika virus ,Small Molecule Libraries ,Inhibitory Concentration 50 ,Mice ,Flaviviridae ,Virology ,Chlorocebus aethiops ,Drug Discovery ,medicine ,Animals ,Humans ,Ascomycin ,Vero Cells ,Pharmacology ,Biological Products ,Innate immune system ,biology ,Zika Virus Infection ,Zika Virus ,biology.organism_classification ,High-Throughput Screening Assays ,Vero cell ,Streptomyces hygroscopicus ,medicine.drug - Abstract
Zika virus (ZIKV) infection could lead to Guillain-Barre syndrome in adults and microcephaly in the newborns from infected pregnant women. To date, there is no specific drug for the treatment of ZIKV infection. In this study, we sought to screen inhibitors against ZIKV infection from a natural product library. A ZIKV replicon was used to screen a library containing 1680 natural compounds. We explored the antiviral mechanism of the compound candidate in vitro and in vivo infection models. Ascomycin, a macrolide from Streptomyces hygroscopicus, was identified with inhibitory effect against ZIKV in Vero cells (IC50 = 0.11 μM), hepatoma cell Huh7 (IC50 = 0.38 μM), and glioblastoma cell SNB-19 (IC50 = 0.06 μM), far below the cytotoxic concentrations. Mechanistic study revealed that Ascomycin suppressed ZIKV RNA replication step during the life cycle and the regulation of calcineurin-NFAT pathway maybe involved in this inhibitory effect, independent of innate immunity activation. Moreover, we found that Ascomycin also inhibited the infection of other Flaviviridae members, such as hepatitis C virus and dengue virus. Ascomycin reduced ZIKV load in blood by up to 3500-fold in A129 mice. Meanwhile, the infection in the mice brain was undetectable by immunohistochemistry staining. Together, these findings reveal a critical role of Ascomycin in the inhibition of ZIKV and related viruses, facilitating the development of novel antiviral agents.
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- 2021
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14. Development of cell culture infectious clones for hepatitis C virus genotype 1b and transcription analysis of 1b-infected hepatoma cells
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Yuanping Zhou, Fei Xiao, Haihe Wang, Dade Rong, Zhenzhen Zhang, Jinqian Li, Guirong Rao, Yi-Ping Li, Jiawei Hao, Liang Rong, Yang Yang, Chengyao Li, Qing Zhou, and Ling Ma
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Carcinoma, Hepatocellular ,Genotype ,Sofosbuvir ,Hepatitis C virus ,Cell Culture Techniques ,Clone (cell biology) ,Hepacivirus ,Viral Nonstructural Proteins ,Biology ,Virus Replication ,medicine.disease_cause ,Antiviral Agents ,Heterocyclic Compounds, 4 or More Rings ,Virus ,Cell Line, Tumor ,Virology ,medicine ,Humans ,Pharmacology ,Infectivity ,medicine.disease ,digestive system diseases ,Clone Cells ,Cell culture ,Hepatocellular carcinoma ,RNA, Viral ,Carbamates ,medicine.drug - Abstract
Globally, hepatitis C virus (HCV) genotype 1b is the most prevalent, and its infection has been found to associate with a higher risk of hepatocellular carcinoma (HCC) than other genotype viruses. However, an efficient infectious HCV genotype 1b culture system is unavailable, which has largely hampered the study of this important genotype virus. In this study, by using a systematic approach combining the sequences of infectious 1a TNcc clone and adaptive mutations, we succeeded in culture adaption of two full-length 1b clones for the reference strain Con1 and a clinical isolate A6, and designated as Con1cc and A6cc, respectively. Con1cc and A6cc replicated efficiently in hepatoma Huh7.5.1 cells, released HCV infectivity titers of 104.1 and 103.72 focus forming units per milliliter, respectively, and maintained the engineered mutations after passages. Both viruses responded to sofosbuvir and velpatasvir in a dose-dependent manner. With culture infectious 1b clones, we characterized the transcriptomes of 1b Con1cc-infected cells, in comparison with 2a-infected and uninfected cells. In conclusion, we have developed two infectious clones for genotype 1b and shown a novel strategy for culture adaptation of HCV isolates by using a genetically close backbone sequence. Furthermore, this study provides transcriptional landscape of HCV 1b-infected hepatoma cells facilitating the study of genotype 1b infection.
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- 2021
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15. Avasimibe: A novel hepatitis C virus inhibitor that targets the assembly of infectious viral particles
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Longbo Hu, Xiu Qiu, Hua Cai, Jing Xiao, Huimin Xia, Wenxia Yao, Tao Peng, Jinqian Li, and Yi-Ping Li
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Gene Expression Regulation, Viral ,0301 basic medicine ,Apolipoprotein E ,Genotype ,Apolipoprotein B ,Combination therapy ,Hepatitis C virus ,Sterol O-acyltransferase ,Down-Regulation ,Hepacivirus ,Drug resistance ,Acetates ,medicine.disease_cause ,Antiviral Agents ,Microsomal triglyceride transfer protein ,03 medical and health sciences ,Apolipoproteins E ,Viral life cycle ,Cell Line, Tumor ,Virology ,Acetamides ,medicine ,Humans ,RNA, Small Interfering ,Apolipoproteins B ,Pharmacology ,Lipid Regulating Agents ,Sulfonamides ,biology ,Virus Assembly ,Virion ,Hepatitis C, Chronic ,Lipid Metabolism ,030104 developmental biology ,Host-Pathogen Interactions ,biology.protein ,Sulfonic Acids ,Carrier Proteins ,Sterol O-Acyltransferase - Abstract
Direct-acting antivirals (DAAs), which target hepatitis C virus (HCV) proteins, have exhibited impressive efficacy in the management of chronic hepatitis C. However, the concerns regarding high costs, drug resistance mutations and subsequent unexpected side effects still call for the development of host-targeting agents (HTAs) that target host factors involved in the viral life cycle and exhibit pan-genotypic antiviral activity. Given the close relationship between lipid metabolism and the HCV life cycle, we investigated the anti-HCV activity of a series of lipid-lowering drugs that have been approved by government administrations or proven safety in clinical trials. Our results showed that avasimibe, an inhibitor of acyl coenzyme A:cholesterol acyltransferase (ACAT), exhibited marked pan-genotypic inhibitory activity and superior inhibition against HCV when combined with DAAs. Moreover, avasimibe significantly impaired the assembly of infectious HCV virions. Mechanistic studies demonstrated that avasimibe induced downregulation of microsomal triglyceride transfer protein expression, resulting in reduced apolipoprotein E and apolipoprotein B secretion. Therefore, the pan-genotypic antiviral activity and clinically proven safety endow avasimibe exceptional potential as a candidate for combination therapy with DAAs. In addition, the discovery of the antiviral properties of ACAT inhibitors also suggests that inhibiting the synthesis of cholesteryl esters might be an additional target for the therapeutic intervention for chronic HCV infection.
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- 2017
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16. Activation of the TLR2-mediated downstream signaling pathways NF-κB and MAPK is responsible for B7-H3-augmented inflammatory response during S. pneumoniae infection
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Xiangying Meng, N.M. Foley, Yi-Ping Li, Min Liu, Jian Wang, Xuqin Chen, Yahui Chai, Jiang Huai Wang, H. Paul Redmond, and Xiaoyan Shi
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Male ,0301 basic medicine ,MAPK/ERK pathway ,Chemokine ,B7 Antigens ,Time Factors ,MAP Kinase Signaling System ,Immunology ,Stimulation ,p38 Mitogen-Activated Protein Kinases ,Proinflammatory cytokine ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Animals ,Immunology and Allergy ,Enzyme Inhibitors ,Phosphorylation ,Cells, Cultured ,Mice, Inbred BALB C ,biology ,Meningitis, Pneumococcal ,Chemistry ,Transcription Factor RelA ,Brain ,NF-κB ,Gene Expression Regulation, Bacterial ,Toll-Like Receptor 2 ,Cell biology ,TLR2 ,Streptococcus pneumoniae ,030104 developmental biology ,Animals, Newborn ,Neurology ,biology.protein ,Cytokines ,Tumor necrosis factor alpha ,Microglia ,Neurology (clinical) ,030217 neurology & neurosurgery - Abstract
It has been reported that B7-H3, a costimulatory protein, participates in the development and progression of experimental pneumococcal meningitis by amplifying the TLR2-mediated inflammatory response. This study attempted to clarify the pathway(s) of TLR2 signaling involved in B7-H3-augmented inflammatory response during S. pneumoniae infection. Murine microglial cell line N9 cells and primary murine microglial cells were infected with S. pneumoniae alone or in combination with B7-H3. Although B7-H3 stimulation failed to further enhance S. pneumoniae-upregulated mRNA and protein expression of TLR2, it strongly augmented S. pneumoniae-induced phosphorylation of NF-κB p65, MAPK p38, and ERK1/2 in both N9 cells and primary microglial cells. Notably, B7-H3 itself did not activate NF-κB p65, MAPK p38, and ERK1/2. Furthermore, deactivation of NF-κB p65, MAPK p38, and ERK1/2 with their specific inhibitors significantly attenuated B7-H3-amplified proinflammatory cytokine and chemokine release from S. pneumoniae-infected microglial cells. Importantly, blockage of NF-κB p65, MAPK p38, or ERK1/2 in vivo substantially diminished B7-H3-augmented TNF-α levels in the brain of S. pneumoniae-infected mice. These results indicate that the activation of both NF-κB and MAPKs is predominantly responsible for B7-H3-augmented inflammatory response during S. pneumoniae infection.
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- 2017
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17. Downregulation of autophagy-related gene ATG5 and GABARAP expression by IFN-λ1 contributes to its anti-HCV activity in human hepatoma cells
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Jinming Su, Jieliang Li, Zang Ning, Hui Chen, Shoucai Fang, Xu Li, Jiegang Huang, Yu Li, Bingyu Liang, Li Ye, Yi-Ping Li, Hao Liang, Junjun Jiang, Wen-Zhe Ho, and Bo Zhou
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0301 basic medicine ,GABARAP ,ATG5 ,Down-Regulation ,Hepacivirus ,Biology ,Virus Replication ,Antiviral Agents ,Autophagy-Related Protein 5 ,03 medical and health sciences ,chemistry.chemical_compound ,Downregulation and upregulation ,Interferon ,Cell Line, Tumor ,Virology ,Autophagy ,medicine ,Humans ,Adaptor Proteins, Signal Transducing ,Pharmacology ,RIG-I ,Liver Neoplasms ,Tunicamycin ,Hepatitis C ,digestive system diseases ,MicroRNAs ,030104 developmental biology ,chemistry ,Hepatocytes ,Cancer research ,Interferons ,Signal transduction ,Apoptosis Regulatory Proteins ,Microtubule-Associated Proteins ,Signal Transduction ,medicine.drug - Abstract
Type-III interferon (IFN-λ), the most recently discovered family of IFNs, shares common features with type I IFNs, but also has many distinctive activities. It is not clear that whether IFN-λ has additional antiviral mechanisms. In this study, we investigated the effects of IFN-λ on autophagy, a cellular process closely related to hepatitis C virus (HCV) infection in human hepatoma Huh7 cells. Our results showed that IFN-λ1 treatment inhibit autophagic activity in Huh7 cells, as evidenced by the decreased expression of microtubule-associated protein 1 light chain 3B (LC3B)-II and conversion of LC3B-I to LC3B-II, decreased formation of GFP-LC3 puncta and accumulation of autophagosomes. IFN-λ1 could also inhibit HCV-induced or tunicamycin (a known inducer of autophagy with similar mechanism to HCV infection) -induced LC3B-II expression and autophagosome formation. Through PCR array, real time RT PCR, and western blot, two autophagy-related genes, ATG5 and GABARAP, were identified and verified to be down-regulated by IFN-λ1 treatment, either in HCV-uninfected Huh7 cells or in HCV JFH-1-infected cells. Overexpression of ATG5 and/or GABARAP could partly recover the IFN-λ1-inhibited HCV replication. Mechanism research demonstrated that IFN-λ1 could induce the expression of miR-181a and miR-214 (targeting ATG5 and GABARAP respectively), by which down-regulates ATG5 and GABARAP expression. Taken together, our results indicate that suppression of the autophagy response by IFN-λ1 contributes to IFN-λ1 anti-HCV activity. The results also provide a theoretical basis for improving the effectiveness of IFN treatment of HCV infection through inhibition of the HCV-induced autophagy response.
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- 2017
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18. Texture and surface feature-mediated striking improvements on multiple direct compaction properties of Zingiberis Rhizoma extracted powder by coprocessing with nano-silica
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Yue Zhang, Yi Feng, Lan Shen, Yan-Long Hong, Yi-Ping Li, Fei Wu, and Xiao Lin
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Materials science ,Drug Compounding ,Compaction ,Pharmaceutical Science ,Percolation threshold ,02 engineering and technology ,Silicon Dioxide ,021001 nanoscience & nanotechnology ,030226 pharmacology & pharmacy ,Excipients ,Microcrystalline cellulose ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,Tensile Strength ,Ultimate tensile strength ,Nano ,Surface roughness ,Texture (crystalline) ,Powders ,Composite material ,0210 nano-technology ,Dispersion (chemistry) ,Tablets - Abstract
The study aims to markedly improve direct compaction (DC) properties of Zingiberis Rhizoma extracted powder (ZR) by modifying its texture and surface properties with nano-silica (NS). A wet coprocessing method was applied to evenly distribute up to 33.3% NS to ZR. To clarify uniqueness of NS, microcrystalline cellulose (MCC), a superior filler-binder in DC, was used as control. Coprocessed particles and physical mixtures (PMs) were comprehensively evaluated for surface features, micromeritic properties, and texture and compacting parameters. Compared to MCC, NS could more significantly modify the texture and surface features of ZR (e.g., hardness, cohesiveness, yield pressure, and nanoscaled surface roughness) via coprocessing, resulting in more striking improvements on multiple DC properties of ZR, including tabletability, flowability, lubricant sensitivity, hygroscopicity, etc. Especially, tensile strength (σt) of coprocessed ZR-NS (1:0.5) tablets was 4.62 and 3.22 times that of ZR and ZR-MCC counterparts pressed at 210 MPa, respectively. Moreover, percolation thresholds of σt enhancement were observed for ZR-NSs, but not for ZR-MCCs. Evaluation by the SeDeM expert system indicated that some ZR-NSs (but no ZR-MCCs) were qualified for DC. Collectively, coprocessing with NS by liquid dispersion appears to be a novel, effective, and pragmatic option for DC of drugs like ZR.
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- 2021
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19. Large scale environmental drivers of biocrust distribution and development across a sandy desert in China
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Xin-Kai Li, Qing-Xuan Wang, Yi-Ping Li, Chongfeng Bu, Ting-Long Zhang, Qiu-Yu Liu, Meng-Chen Ju, and Bingyin Li
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Biomass (ecology) ,010504 meteorology & atmospheric sciences ,biology ,ved/biology ,ved/biology.organism_classification_rank.species ,04 agricultural and veterinary sciences ,Soil carbon ,biology.organism_classification ,01 natural sciences ,Bulk density ,Shrub ,Arid ,Moss ,Soil pH ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Aridity index ,Physical geography ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
Biological soil crusts (biocrusts) are widely distributed in arid and semiarid ecosystems and provide critical ecological functions. Understanding how biocrusts change across broad regional scales allows us to manage them more effectively under changing climates and land-use pressures. Based on field surveys, we used boosted regression trees and correlation analysis to examine the changes in cover, distribution and developmental characteristics of biocrust mosses and cyanobacteria, and environmental factors at 40 sites in the Mu Us Sandland in northwestern China. We found that higher elevation sites (~1342 m) were the most suitable for biocrust distribution, and preferred sites were characterized by greater vegetation cover (>43%), values of the aridity index (>0.34), slope (>6.6°), soil pH (>8.85) and soil organic carbon (>0.50%). Increasing levels of disturbance (>1.15 kg dung ha−1) suppressed biocrusts. Moss crust development (e.g., biomass, thickness, bulk density) was significantly positively related to vegetation cover, aridity index, and soil organic carbon, and moss crusts tended to prefer shady shrub communities at low elevations. Shady and steep (5 – 15°) slopes and higher soil nutrient contents were positively correlated with cyanobacteria development. Reduced rainfall and increasing disturbance intensity would reduce the distribution and development of biocrusts. Our study provides a basis for informed decision making about how to manage moss and cyanobacterial crusts in the Mu Us Sandland as the region becomes hotter and drier.
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- 2021
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20. Pollution resistance assessment of existing landscape plants on Beijing streets based on air pollution tolerance index method
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Minghao Zhu, Zheng Yang, Yanju Liu, Yi-ping Li, Xing Chen, and Pengqian Zhang
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Chlorophyll ,0106 biological sciences ,Pollution ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,Air pollution ,Ascorbic Acid ,010501 environmental sciences ,medicine.disease_cause ,01 natural sciences ,Air Pollution ,Environmental monitoring ,Botany ,medicine ,Rosa chinensis ,Vehicle Emissions ,0105 earth and related environmental sciences ,media_common ,Ailanthus altissima ,Air Pollutants ,biology ,Resistance (ecology) ,Public Health, Environmental and Occupational Health ,Water ,General Medicine ,Hydrogen-Ion Concentration ,Plants ,biology.organism_classification ,Ascorbic acid ,Plant Leaves ,Agronomy ,Beijing ,Environmental science ,Fraxinus chinensis ,Environmental Monitoring ,010606 plant biology & botany - Abstract
Various plant species of green belt in urban traffic area help to reduce air pollution and beautify the city environment. Those plant species growing healthily under long-term atmospheric pollution environment are considered to be resilient. This study aims to identify plant species that are more tolerant to air pollution from traffic and to give recommendations for future green belt development in urban areas. Leaf samples of 47 plant species were collected from two heavy traffic roadside sites and one suburban site in Beijing during summer 2014. Four parameters in leaves were separately measured including relative water content (RWC), total chlorophyll content (TCH), leaf-extract pH (pH), and ascorbic acid (AA). The air pollution tolerance index (APTI) method was adopted to assess plants' resistance ability based on the above four parameters. The tolerant levels of plant species were classified using two methods, one by comparing the APTI value of individual plant to the average of all species and another by using fixed APTI values as standards. Tolerant species were then selected based on combination results from both methods. The results showed that different tolerance orders of species has been found at the three sampling sites due to varied air pollution and other environmental conditions. In general, plant species Magnolia denudata, Diospyros kaki, Ailanthus altissima, Fraxinus chinensis and Rosa chinensis were identified as tolerant species to air pollution environment and recommend to be planted at various location of the city, especially at heavy traffic roadside.
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- 2016
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21. Dexmedetomidine inhibits pyroptosis by down-regulating miR-29b in myocardial ischemia reperfusion injury in rats
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Yi Zhong, Hong Gao, Yi-Ping Li, Yongqiang Yin, and Bai-Long Hu
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Male ,0301 basic medicine ,Immunology ,Cell ,Down-Regulation ,Myocardial Reperfusion Injury ,Pharmacology ,Protective Agents ,Cell Line ,Rats, Sprague-Dawley ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Lactate dehydrogenase ,Troponin I ,Adrenergic alpha-2 Receptor Agonists ,Pyroptosis ,medicine ,Animals ,Humans ,Immunology and Allergy ,Receptor ,Arc (protein) ,Chemistry ,Myocardium ,Forkhead Box Protein O3 ,medicine.disease ,Rats ,Disease Models, Animal ,MicroRNAs ,030104 developmental biology ,medicine.anatomical_structure ,Apoptosis ,Reperfusion Injury ,030220 oncology & carcinogenesis ,Reperfusion injury ,Dexmedetomidine - Abstract
Objective Dexmedetomidine (DEX) was reported to protect heart against ischemic-reperfusion (IR) but the mechanism herein remains elusive. This study aims to explore the mechanism of DEX on pyroptosis induced by myocardial ischemic reperfusion (MIR). Methods MIR rat models were established and injected DEX or miR-29b agomir/antagomir separately. The possible effect of DEX or miR-29b on myocardial cells was assessed according to measurement on creatine kinase-MB (CK-MB), cardiac troponin I (cTnI), interleukin-1β (IL-1β) and interleukin-18 (IL-18), myocardial infarction size, myocardial injury and apoptosis. Western blot determined the expression levels of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing CARD (ASC) and cleaved-caspase-1. Hypoxia/reoxygenation (H/R) cell model was established. The lactate dehydrogenase (LDH) content released by myocardial cells was examined. The relation between miR-29b and FoxO3a was confirmed by dual luciferase reporter gene assay. FoxO3a or ARC level was elevated in H/R myocardial cells to detect its effect on pyroptosis. Results MIR rat models were successfully established, in which cell pyroptosis was triggered as evidenced by increased expression levels of NLRP3, ASC and cleaved-caspase-1. Rats with DEX precondition had attenuated cell pyroptosis and ameliorated inflammatory response. FoxO3a was a target of miR-29b. MiR-29b agomir or miR-29b antagomir could inhibit or promote the protective effect of DEX on MIR. Overexpression of FoxO3a/ARC axis could suppress myocardial pyroptosis induced by H/R. Conclusion DEX could ameliorate MIR injury (MIRI) and H/R injury in rats and inhibit H/R induced pyroptosis in myocardial cells via down-regulating miR-29b to activate FoxO3a/ARC axis.
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- 2020
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22. Blockade of adenosine A1 receptor in nucleus tractus solitarius attenuates baroreflex sensitivity response to dexmedetomidine in rats
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Qian Liu, Yongqiang Yin, Lei Tian, Yi-Ping Li, Guoqiang Tang, and Yi Zhong
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Male ,0301 basic medicine ,Agonist ,medicine.drug_class ,Adenosine A1 Receptor Antagonists ,Pharmacology ,Baroreflex ,Rats, Sprague-Dawley ,03 medical and health sciences ,Adenosine A1 receptor ,0302 clinical medicine ,Adrenergic alpha-2 Receptor Agonists ,Solitary Nucleus ,medicine ,Animals ,Dexmedetomidine ,Molecular Biology ,Phenylephrine ,Receptor, Adenosine A1 ,business.industry ,General Neuroscience ,Solitary nucleus ,Atipamezole ,Adenosine ,Rats ,030104 developmental biology ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Developmental Biology ,medicine.drug - Abstract
The α2-adrenergic receptor (α2-AR) agonist dexmedetomidine increases baroreflex sensitivity (BRS). In the current study, we examined the potential role of adenosine A1 receptor (A1R) within the nucleus tractus solitaries (NTS) in such a response. Briefly, adult male Sprague-Dawley rats were anesthetized and randomly received microinjection of selective A1R antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX; 0.1 pmol/1 μl) or saline vehicle into the right NTS. Ten min after the microinjection, dexmedetomidine infusion started at a rate of 30 μg/kg over 15 min followed by infusion at 15 μg·kg−1·h−1 for 105 min, or 100 μg/kg over 15 min followed by infusion at 50 μg·kg−1·h−1 for 105 min. BRS was examined using a standard phenylephrine method prior to infusion (T0), 60 min (T1) and 120 min (T2) after dexmedetomidine infusion started. Adenosine concentration in plasma and brainstem was measured with high-performance liquid chromatography with vs. without α2-AR antagonist atipamezole pretreatment (0.5 mg/kg, i.p.). Dexmedetomidine increased BRS at both 30 (T0: 0.55 ± 0.25 vs. T1: 2.45 ± 0.37, T2: 2.26 ± 0.56 ms/mmHg, P
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- 2020
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23. Corrigendum to 'Deletion of core-binding factor β (Cbfβ) in mesenchymal progenitor cells provides new insights into Cbfβ/Runxs complex function in cartilage and bone development' [Bone 65 (2014) 49–59]
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Yiping Wang, Joel Jules, Mengrui Wu, Jian-Zhong Shao, Matthew McConnell, Yi-Ping Li, Wei Chen, Chenguan Li, Yun Lu, Yong-Jun Wang, and Guochun Zhu
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Histology ,medicine.anatomical_structure ,Bone development ,Physiology ,Chemistry ,Endocrinology, Diabetes and Metabolism ,Cartilage ,Mesenchymal stem cell ,medicine ,Progenitor cell ,Core binding factor ,Function (biology) ,Cell biology - Published
- 2019
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24. A proposed mother-friendly childbirth model for Taiwanese women and obstetricians' attitudes toward it
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Chien-Nan Lee, Chih-Hsin Yeh, Ya-Ling Yang, Yi-Ping Li, Su-Chen Kuo, Heng-Cheng Hsu, and Shin-Yu Lin
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Adult ,Episiotomy ,medicine.medical_specialty ,Attitude of Health Personnel ,Cross-sectional study ,medicine.medical_treatment ,episiotomy ,Taiwan ,amniotomy ,intermittent fetal monitoring ,lcsh:Gynecology and obstetrics ,Patient Positioning ,mother-friendly childbirth ,Obstetrics and gynaecology ,Pregnancy ,Obstetrics and Gynaecology ,medicine ,Humans ,Pain Management ,Childbirth ,Practice Patterns, Physicians' ,Fetal Monitoring ,lcsh:RG1-991 ,reproductive and urinary physiology ,Obstetrics ,business.industry ,Obstetrics and Gynecology ,Enema ,Focus Groups ,Delivery, Obstetric ,medicine.disease ,Focus group ,Position (obstetrics) ,Cross-Sectional Studies ,Family medicine ,enema ,Female ,business - Abstract
Objective Pleasant and humane childbirth is every mother's wish. The objective of this study was to propose a practicable mother-friendly childbirth model tailored to Taiwanese women in order to improve the quality of perinatal care and maternal satisfaction. Material and methods In this study, the guidelines of several countries were systematically reviewed, and a standard set of clinical guidelines were established by a focus group. In addition, a total of 172 Taiwanese obstetricians were visited, and a cross-sectional study of these obstetricians' attitudes toward the practicality and effectiveness of the model was performed using questionnaires. Results A total of 10 suggestions were developed for this woman-friendly childbirth model, including: (1) intermittent fetal monitoring for low-risk pregnancy, (2) no routine enema, (3) no routine perineal shaving, (4) no routine restricted oral intake, (5) no routine parenteral fluid support, (6) no routine elective amniotomy, (7) nonpharmacological pain management, (8) upright position during childbirth, (9) delayed pushing, and (10) restrictive episiotomy. Taiwanese obstetricians approved of no routine oral intake restriction and providing nonmedical pain relief. The majority of obstetricians disagreed that perineal shaving and routine elective amniotomy were necessary, and agreed to modify their practice according to the suggestions. Suggestions were still being debated, such as no routine parenteral fluid support, using an upright position for childbirth, and delayed pushing. Intermittent fetal monitoring for low-risk pregnancy, no routine enema, and restrictive episiotomy were questioned by many Taiwanese obstetricians. Conclusion Several suggestions were made in this model. However, there was still no consensus of Taiwanese obstetricians. More evidence for the advantages and disadvantages of the various suggestions was needed to convince Taiwanese obstetrician to modify their routine practice.
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- 2015
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25. A novel biomimetic logic gate for sensitive and selective detection of Pb(II) base on porous alumina nanochannels
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Peng Zhang, Shucheng Liu, Yi-Ping Li, Hongwu Ji, Guo-Zhu Shen, Zhi-Meng Chen, Qian Zhongji, and Cheng-Yong Li
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Steric effects ,chemistry.chemical_classification ,Detection limit ,Biomolecule ,Analytical chemistry ,Ion ,lcsh:Chemistry ,Membrane ,lcsh:Industrial electrochemistry ,lcsh:QD1-999 ,chemistry ,Linear range ,Logic gate ,Electrochemistry ,Ion channel ,lcsh:TP250-261 - Abstract
A novel biomimetic logic gate sensor for Pb2+ is established using porous alumina membrane nanochannels modified with morpholino and DNA. It is based on electrochemical detection, and the current response from the diffusion flux of Fe(CN)63− is influenced by the steric blockage and charge repulsion in nanochannels. A limit of detection (0.1 nM) and good linear range (0.1 nM–5 μM) for Pb2+ analysis are achieved in the tenth cycle. The sensing strategy shows prospective application in drug release, artificial ion channels, DNA logic gates for controlling biomolecule, and ion translocation. Keywords: Nanochannel, Steric blockage, Charge repulsion, Pb2+ detection
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- 2015
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26. Macroinvertebrate assemblages in relation to environments in the West River, with implications for management of rivers affected by channel regulation projects
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Baozhu Pan, Yong-jun Lu, Zhiwei Li, Yi-Ping Li, Wen-Jun Yang, and Zhaoyin Wang
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Hydrology ,Dike ,geography ,geography.geographical_feature_category ,River ecosystem ,Ecology ,Hydraulic engineering ,Silt ,Benthic zone ,Canonical correspondence analysis ,Bank ,Geology ,Channel (geography) ,Earth-Surface Processes - Abstract
Rivers have many service functions, and play an important role in people's living and agricultural production. During the last decades, intensive human activities have been threatening river ecosystem. For shipping, hydraulic engineering facilities (e.g. spur dikes) have been built along river bank to increase water depth. However, natural habitat conditions (i.e. substrate, flow regime, water physico-chemical properties) are accordingly altered. Therefore, it is necessary to select representative organisms as indicators to assess the aquatic ecological status of different habitat conditions, furthermore, management strategies are to be put forward. Macroinvertebrates are often considered as good indicators of long-term changes in environments due to their confinement to the bottom, long life cycles and limited abilities of movement. In this study, field investigations of macroinvertebrates in the West River were conducted in November 2009 (at low water level) and May 2010 (at high water level). Altogether 70 taxa of macroinvertebrates belonging to 30 families and 59 genera were identified. Among them were 16 annelids, 21 mollusks, 32 arthropods and 1 miscellaneous animal. The average density and biomass of total macroinvertebrates were 140 ind m −2 and 0.23 g dry weight m −2 , respectively. Canonical Correspondence Analysis (CCA) revealed that major factors structuring macroinvertebrate assemblages were flow velocity ( U ), water depth ( Z ), conductivity (Cond), total nitrogen (TN) and substrates (clay, silt, cobbles and bedrock). Density and diversity of macroinvertebrates peaked in the cobbles, while biomass reached the maximum in the bedrock. It is indicated that stable and heterogeneous habitats were beneficial to development of benthic assemblages. To conserve these habitats, type and construction position of spur dikes should receive enough attentions. Thus, it is suggested that as few spur dikes as possible can be constructed in the riverbed covered with cobbles and bedrocks. Otherwise, the angle between spur dike and river bank need be analyzed to generate the appropriate flow regime which can prevent the stable substrates from being buried by sands. Some advice about length and separation distance of spur dikes is also presented.
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- 2015
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27. Deletion of core-binding factor β (Cbfβ) in mesenchymal progenitor cells provides new insights into Cbfβ/Runxs complex function in cartilage and bone development
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Yiping Wang, Joel Jules, Matthew McConnell, Guochun Zhu, Yong-Jun Wang, Yi-Ping Li, Mengrui Wu, Yun Lu, Wei Chen, Jian-Zhong Shao, and Chenguan Li
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medicine.medical_specialty ,Histology ,Physiology ,Endocrinology, Diabetes and Metabolism ,Biology ,Polymerase Chain Reaction ,Article ,Chondrocyte ,Mice ,chemistry.chemical_compound ,Calcification, Physiologic ,Osteoclast ,Internal medicine ,medicine ,Animals ,Endochondral ossification ,DNA Primers ,Bone Development ,Base Sequence ,Cartilage ,Core Binding Factors ,Mesenchymal Stem Cells ,Osteoblast ,Cell biology ,RUNX2 ,medicine.anatomical_structure ,Endocrinology ,RUNX1 ,chemistry ,Core Binding Factor Alpha 2 Subunit ,Intramembranous ossification ,Gene Deletion - Abstract
Core-binding factor β (Cbfβ) is a subunit of the Cbf family of heterodimeric transcription factors, which plays a critical role in skeletal development through its interaction with the Cbfα subunits, also known as Runt-related transcription factors (Runxs). However, the mechanism by which Cbfβ regulates cartilage and bone development remains unclear. Existing Cbfβ-deficient mouse models cannot specify the role of Cbfβ in skeletal cell lineage. Herein, we sought to specifically address the role of Cbfβ in cartilage and bone development by using a conditional knockout (CKO) approach. A mesenchymal-specific Cbfβ CKO mouse model was generated by using the Dermo1-Cre mouse line to specifically delete Cbfβ in mesenchymal stem cells, which give rise to osteoblasts and chondrocytes. Surprisingly, the mutant mice had under-developed larynx and tracheal cartilage, causing alveolus defects that led to death shortly after birth from suffocation. Also, the mutant mice exhibited severe skeletal deformities from defective intramembranous and endochondral ossification, owing to delayed chondrocyte maturation and impaired osteoblast differentiation. Almost all bones of the mutant mice, including the calvariae, vertebrae, tibiae, femurs, ribs, limbs and sternums were defective. Importantly, we showed that Cbfβ was expressed throughout the skeleton during both embryonic and postnatal development, which explains the multiple-skeletal defects observed in the mutant mice. Consistently, Cbfβ deficiency impaired both chondrocyte proliferation and hypertrophy zone hypertrophy during growth-plate development in the long bones of mutant mice. Notably, Cbfβ, Runx1 and Runx2 displayed different expression patterns in the growth plates of the wild-type mice, indicating that Cbfβ/Runx1 complex and Cbfβ/Runx2 complex may regulate chondrocyte proliferation and hypertrophy, respectively, in a spatial and temporal manner. Cbfβ deletion in the mesenchymal progenitors affected bone development by dramatically down-regulating Collagen X (Col X) and Osterix (Osx) but had a dispensable effect on osteoclast development. Collectively, the results demonstrate that Cbfβ mediates cartilage and bone development by interacting with Runx1 and Runx2 to regulate the expressions of Col X and Osx for chondrocyte and osteoblast development. These findings not only reveal a critical role for Cbfβ in cartilage and bone development but also facilitate the design of novel therapeutic approaches for skeletal diseases.
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- 2014
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28. Discovery of 2-methoxy-3-phenylsulfonamino-5-(quinazolin-6-yl or quinolin-6-yl)benzamides as novel PI3K inhibitors and anticancer agents by bioisostere
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Juan Wang, Qi-Bing Mei, Yi-Ping Li, Jiangang Chen, Guang-De Yang, Xiao-Meng Wang, Huan Li, Yan Li, Shao Teng, and San-Qi Zhang
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Male ,Stereochemistry ,Mice, Nude ,Antineoplastic Agents ,Pharmacology ,Mice ,chemistry.chemical_compound ,Cell Line, Tumor ,Neoplasms ,Drug Discovery ,Quinazoline ,Animals ,Humans ,MTT assay ,Benzamide ,Protein kinase B ,PI3K/AKT/mTOR pathway ,Cell Proliferation ,Phosphoinositide-3 Kinase Inhibitors ,Mice, Inbred BALB C ,Chemistry ,TOR Serine-Threonine Kinases ,Organic Chemistry ,General Medicine ,Cell culture ,Benzamides ,Quinazolines ,Bioisostere ,Human cancer ,Signal Transduction - Abstract
2-Substituted-3-sulfonamino-5-(quinazolin-6-yl or quinolin-6-yl)benzamides have been proposed as novel structures of PI3K inhibitors and anticancer agents based on bioisostere. In the present study, 2-substituted-3-sulfonamino-5-(4-morpholinoquinazolin-6-yl)benzamides and 2-methoxy-3-sulfonamino-5-(4-morpholinoquinolin-6-yl)benzamides were synthesized. Their antiproliferative activities in vitro were evaluated via MTT assay against four human cancer cell lines, including A549, HCT-116, U-87 MG and KB. The SAR of the title compounds was preliminarily discussed. Compound 1a with potent antiproliferative activity was tested for its inhibitory activity against PI3K and mTOR and its effect on the AKT and p-AKT 473 . The anticancer effect of 1a was evaluated in established nude mice U-87 MG xenograft model. The results suggest that compound 1a can significantly inhibit PI3K/AKT/mTOR pathway and tumor growth. These findings strongly support the assumption that title compounds are potent PI3K inhibitors and anticancer agents.
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- 2014
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29. ZIP4 Promotes Muscle Wasting and Cachexia in Mice With Orthotopic Pancreatic Tumors by Stimulating RAB27B-Regulated Release of Extracellular Vesicles From Cancer Cells
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Courtney W. Houchen, Yusheng Luo, Yi-Ping Li, Yuqing Zhang, Jingxuan Yang, Michael S. Bronze, Jing Fang, Xiaobo Cui, Lei Zheng, Mingyang Liu, Zicheng Zhang, Can Xu, Xiaoling Ni, Jie Yan, Guohua Zhang, Zhao-Shen Li, Qiang Zhang, John P. Hagan, Barish H. Edil, Huiyun Zhu, Min Li, Aminah Jatoi, Martin E. Fernandez-Zapico, and Vivian F. Zhu
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0301 basic medicine ,Cachexia ,Mice, Nude ,Kaplan-Meier Estimate ,Sensitivity and Specificity ,p38 Mitogen-Activated Protein Kinases ,Article ,Metastasis ,Extracellular Vesicles ,Mice ,Random Allocation ,03 medical and health sciences ,Pancreatectomy ,0302 clinical medicine ,Reference Values ,Cell Line, Tumor ,Pancreatic cancer ,Myosin ,medicine ,Animals ,Humans ,Muscle, Skeletal ,Cation Transport Proteins ,Hepatology ,Chemistry ,Myogenesis ,Gastroenterology ,Extracellular vesicle ,medicine.disease ,Xenograft Model Antitumor Assays ,Gene Expression Regulation, Neoplastic ,Pancreatic Neoplasms ,030104 developmental biology ,medicine.anatomical_structure ,rab GTP-Binding Proteins ,Cancer cell ,Cancer research ,030211 gastroenterology & hepatology ,Pancreas - Abstract
Background & Aims Cachexia, which includes muscle wasting, is a frequent complication of pancreatic cancer. There are no therapies that reduce cachexia and increase patient survival, so it is important to learn more about its mechanisms. The zinc transporter ZIP4 promotes growth and metastasis of pancreatic tumors. We investigated its effects on muscle catabolism via extracellular vesicle (EV)-mediated stimulation of mitogen-activated protein kinase 14 (p38 MAPK). Methods We studied nude mice with orthotopic tumors grown from human pancreatic cancer cell lines (AsPC-1 and BxPC-3); tumors were removed 8 days after cell injection and analyzed by histology. Mouse survival was analyzed by Kaplan–Meier curves. ZIP4 was knocked down in AsPC-1 and BxPC-3 cells with small hairpin RNAs; cells with empty vectors were used as controls. Muscle tissues were collected from mice and analyzed by histology and immunohistochemistry. Conditioned media from cell lines and 3-dimensional spheroid/organoid cultures of cancer cells were applied to C2C12 myotubes. The myotubes and the media were analyzed by immunoblots, enzyme-linked immunosorbent assays, and immunofluorescence microscopy. EVs were isolated from conditioned media and analyzed by immunoblots. Results Mice with orthotopic tumors grown from pancreatic cancer cells with knockdown of ZIP4 survived longer and lost less body weight and muscle mass than mice with control tumors. Conditioned media from cancer cells activated p38 MAPK, induced expression of F-box protein 32 and UBR2 in C2C12 myotubes, and also led to loss of myofibrillar protein myosin heavy chain and myotube thinning. Knockdown of ZIP4 in cancer cells reduced these effects. ZIP4 knockdown also reduced pancreatic cancer cell release of heat shock protein (HSP) 70 and HSP90, which are associated with EVs, by decreasing CREB-regulated expression of RAB27B. Conclusions ZIP4 promotes growth of orthotopic pancreatic tumors in mice and loss of muscle mass by activating CREB-regulated expression of RAB27B, required for release of EVs from pancreatic cancer cells. These EVs activate p38 MAPK and induce expression of F-box protein 32 and UBR2 in myotubes, leading to loss of myofibrillar myosin heavy chain and myotube thinning. Strategies to disrupt these pathways might be developed to reduce pancreatic cancer progression and accompanying cachexia.
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- 2019
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30. Synthesis and anticancer activity evaluation of a series of [1,2,4]triazolo[1,5-a]pyridinylpyridines in vitro and in vivo
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Xiao-Meng Wang, Congshan Jiang, San-Qi Zhang, Jing Xu, Shemin Lu, Guang-De Yang, Huan Li, and Yi-Ping Li
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Models, Molecular ,Pyridines ,Antineoplastic Agents ,Pharmacology ,Mice ,Structure-Activity Relationship ,In vivo ,Drug Discovery ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Protein kinase B ,Cell Proliferation ,Dose-Response Relationship, Drug ,Molecular Structure ,Chemistry ,Organic Chemistry ,Neoplasms, Experimental ,General Medicine ,Triazoles ,HCT116 Cells ,medicine.disease ,In vitro ,Disease Models, Animal ,Cell culture ,MCF-7 Cells ,Cancer research ,Sarcoma ,Drug Screening Assays, Antitumor ,Human cancer - Abstract
A series of [1,2,4]triazolo[1,5-a]pyridinylpyridines were synthesized and characterized. Their antiproliferative activities in vitro were evaluated by MTT against three human cancer cell lines including HCT-116, U-87 MG and MCF-7 cell lines. The SAR of target compounds was preliminarily discussed. The compounds 1c and 2d with potent antiproliferative activities were tested for their effects on the AKT and p-AKT 473 . The anticancer effect of 1c was evaluated in mice bearing sarcoma S-180 model. The results suggest that the title compounds are potent anticancer agents.
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- 2013
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31. SNX25 regulates TGF-β signaling by enhancing the receptor degradation
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Zhijie Chang, Baoqing Jia, Yongming Ren, Fangli Ren, Shanshan Zhu, Yi-Ping Li, Yinyin Wang, Xinbao Hao, and Yuguang Shi
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R-SMAD ,Endocytic cycle ,Cell Biology ,Receptor-mediated endocytosis ,TGF beta receptor 2 ,Endoglin ,Biology ,Molecular biology ,Clathrin ,Endocytosis ,Protein Structure, Tertiary ,Cell biology ,Mice ,Sorting nexin ,Transforming Growth Factor beta ,Cell Line, Tumor ,TGF beta signaling pathway ,Animals ,Humans ,RNA Interference ,RNA, Small Interfering ,Receptor ,Receptors, Transforming Growth Factor beta ,Sorting Nexins ,Signal Transduction - Abstract
SNXs (sorting nexin), a family of proteins playing roles in cargo sorting and signaling from compartments within the endocytic network, regulate traffic of membrane proteins including TGF-β receptors. Here we report that the full length human and mouse SNX25, a SNX member with PX, PXA and RGS domains, co-localizes with TGF-β receptors, and forms internalized cytosolic punctae upon treatment with TGF-β. While overexpression of SNX25 inhibits TGF-β induced luciferase reporter activity, knocking down endogenous SNX25 by siRNA in NIH3T3 cells elevates the TGF-β receptor levels and facilitates TGF-β signaling. Immunoprecipitation experiments demonstrate that SNX25 interacts with TβRI. Western blot analyses indicate that SNX25 enhances the degradation of TGF-β receptors. SNX25 induced TGF-β receptor degradation is shown via the clathrin dependent endocytosis pathway into lysosome. We have characterized that PXA domain of SNX25 is required for the degradation of TβRI. Our findings demonstrate that SNX25 negatively regulates TGF-β signaling by enhancing the receptor degradation through lysosome pathway.
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- 2011
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32. Campylobacter jejuni induces an anti-inflammatory response in human intestinal epithelial cells through activation of phosphatidylinositol 3-kinase/Akt pathway
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Hanne Ingmer, Yi-Ping Li, Dang Duong Bang, Mogens Madsen, Christina S. Vegge, and Lone Brøndsted
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MAPK/ERK pathway ,Cell signaling ,Cytolethal distending toxin ,Down-Regulation ,Microbiology ,Campylobacter jejuni ,Cell Line ,Campylobacter Infections ,Animals ,Humans ,Phosphorylation ,Protein kinase B ,PI3K/AKT/mTOR pathway ,General Veterinary ,biology ,Kinase ,Interleukin-8 ,Epithelial Cells ,General Medicine ,biology.organism_classification ,Interleukin-10 ,Intestines ,Host-Pathogen Interactions ,Mitogen-Activated Protein Kinases ,Phosphatidylinositol 3-Kinase ,Signal transduction ,Chickens ,Proto-Oncogene Proteins c-akt ,Signal Transduction - Abstract
Campylobacter jejuni (C. jejuni) is the most common cause of human acute bacterial gastroenteritis. Poultry is a major reservoir of C. jejuni and considered an important source of human infections, thus, it is important to understand the host response to C. jejuni from chicken origin. In this study, we demonstrated firstly that a chicken isolate SC11 colonized chicks faster than clinical isolate NCTC11168. Using the SC11, we further studied the host responds to C. jejuni in terms of inflammatory response and involvement of cellular signaling pathways. Infection of C. jejuni SC11 was able to activate phosphatidylinositol 3-kinase (PI3K)/Akt pathway and induce pro-inflammatory interleukin-8 (IL-8) as well as anti-inflammatory cytokine IL-10 in human intestinal epithelial cell line Colo 205. The signalling pathways PI3K/Akt and mitogen-activated protein (MAP) kinases ERK and p38 were involved in C. jejuni-induced IL-8 and IL-10 expression. Inhibition of PI3K resulted in augmentation of C. jejuni-induced IL-8 production, concomitant with down-regulation of IL-10 mRNA, indicating an anti-inflammatory response was activated and associated with the activation of P13K/Akt. Similar effect was observed for cytolethal distending toxin (CDT) deficient mutants. Moreover, we demonstrated that heat-killed bacteria were able to induce IL-8 and IL-10 expression to a lower level than live bacteria. We therefore conclude that C. jejuni activate a PI3K/Akt-dependent anti-inflammatory pathway in human intestinal epithelial cells which may benefit the intracellular survival of C. jejuni during infection.
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- 2011
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33. Mutant (CCTG)n Expansion Causes Abnormal Expression of Zinc Finger Protein 9 (ZNF9) in Myotonic Dystrophy Type 2
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Ralf Krahe, Anna Vihola, Shodimu Emmanuel Olufemi, Mario Sirito, Yi-Ping Li, Jeanette Holmlund-Hampf, Hannu Haapasalo, Bjarne Udd, Linda L. Bachinski, and Olayinka Raheem
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Adult ,Male ,musculoskeletal diseases ,medicine.medical_specialty ,RNA-binding protein ,Biology ,Myotonic dystrophy ,Pathology and Forensic Medicine ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,Myotonic Dystrophy ,Tissue Distribution ,Muscle, Skeletal ,Aged ,030304 developmental biology ,Regulation of gene expression ,Zinc finger ,0303 health sciences ,DNA Repeat Expansion ,Muscle cell differentiation ,Gene Expression Profiling ,Alternative splicing ,Intron ,RNA-Binding Proteins ,Middle Aged ,Microarray Analysis ,medicine.disease ,Molecular biology ,Endocrinology ,Gene Expression Regulation ,Mutation ,RNA splicing ,Female ,030217 neurology & neurosurgery ,Regular Articles ,Myotonic Disorders - Abstract
The mutation that underlies myotonic dystrophy type 2 (DM2) is a (CCTG)n expansion in intron 1 of zinc finger protein 9 (ZNF9). It has been suggested that ZNF9 is of no consequence for disease pathogenesis. We determined the expression levels of ZNF9 during muscle cell differentiation and in DM2 muscle by microarray profiling, real-time RT-PCR, splice variant analysis, immunofluorescence, and Western blotting. Our results show that in differentiating myoblasts, ZNF9 protein was localized primarily to the nucleus, whereas in mature muscle fibers, it was cytoplasmic and organized in sarcomeric striations at the Z-disk. In patients with DM2, ZNF9 was abnormally expressed. First, there was an overall reduction in both the mRNA and protein levels. Second, the subcellular localization of the ZNF9 protein was somewhat less cytoplasmic and more membrane-bound. Third, our splice variant analysis revealed retention of intron 3 in an aberrant isoform, and fourth quantitative allele-specific expression analysis showed the persistence of intron 1 sequences from the abnormal allele, further suggesting that the mutant allele is incompletely spliced. Thus, the decrease in total expression appears to be due to impaired splicing of the mutant transcript. Our data indicate that ZNF9 expression in DM2 patients is altered at multiple levels. Although toxic RNA effects likely explain overlapping phenotypic manifestations between DM1 and DM2, abnormal ZNF9 levels in DM2 may account for the differences in DM1.
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- 2010
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34. Requirement of the Epithelium-specific Ets Transcription Factor Spdef for Mucous Gland Cell Function in the Gastric Antrum
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Xuesong Gu, Dongxu Lin, David Horst, Manoj Bhasin, Towia A. Libermann, Marie G. Joseph, Yi-Ping Li, Michael P. Verzi, Xiaobo Zhang, Ramesh A. Shivdasani, Wei Chen, and Quanli Yang
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medicine.medical_specialty ,Cellular differentiation ,Muscle Proteins ,Mucous gland ,Biology ,Biochemistry ,Mice ,Exocrine Glands ,Internal medicine ,Pyloric Antrum ,medicine ,Animals ,Homeostasis ,education ,Mucin-6 ,Molecular Biology ,Antrum ,Mice, Knockout ,education.field_of_study ,Hyperplasia ,Proto-Oncogene Proteins c-ets ,Mucins ,Trefoil factor 2 ,Cell Biology ,medicine.disease ,Mucus ,Cell biology ,Foveolar cell ,Endocrinology ,Gene Expression Regulation ,Organ Specificity ,Trefoil Factor-2 ,Peptides - Abstract
Mucus-secreting cells of the stomach epithelium provide a protective barrier against damage that might result from bacterial colonization or other stimuli. Impaired barrier function contributes to chronic inflammation and cancer. Knock-out mice for the epithelium-specific transcription factor Spdef (also called Pdef) have defects in terminal differentiation of intestinal and bronchial secretory cells. We sought to determine the physiologic function of Spdef in the stomach, another site of significant levels of Spdef expression. We used in situ hybridization and immunohistochemistry to localize Spdef-expressing cells in the mouse stomach; targeted gene disruption to generate mice lacking Spdef; and histologic, immunologic, and transcriptional profiling approaches to determine the requirements of Spdef in stomach epithelial homeostasis. In wild-type mice, Spdef RNA and protein are expressed predominantly in mucous gland cells of the antrum and in mucous neck cells of the glandular corpus. Within 1.5 years, nearly half of homozygous mutant mice developed profound mucosal hyperplasia of the gastric antrum. Submucosal infiltration of inflammatory cells preceded antral hyperplasia by several weeks. The absence of Spdef impaired terminal maturation of antral mucous gland cells, as reflected in reduced expression of Muc6 and Tff2 and reduced numbers of secretory granules. Antral gene expression abnormalities overlapped significantly with those in Spdef(-/-) colon, including genes implicated in secretory granule traffic and functions. Spdef is required for terminal maturation of antral mucous gland cells to protect animals from gastric inflammation and resulting hyperplasia. These requirements parallel Spdef functions in secretory intestinal cells and suggest a common molecular mechanism for maturation of gastrointestinal secretory lineages.
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- 2010
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35. HCV Genotype 6a Escape From and Resistance to Velpatasvir, Pibrentasvir, and Sofosbuvir in Robust Infectious Cell Culture Models
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Jannie Pedersen, Santseharay Ramirez, Ulrik Fahnøe, Judith M. Gottwein, Jens Bukh, Long V. Pham, and Yi-Ping Li
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0301 basic medicine ,Ledipasvir ,Pyrrolidines ,Daclatasvir ,Genotype ,Sofosbuvir ,viruses ,Hepatitis C virus ,Cell Culture Techniques ,Hepacivirus ,Viral Nonstructural Proteins ,Biology ,medicine.disease_cause ,Antiviral Agents ,Heterocyclic Compounds, 4 or More Rings ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cell Line, Tumor ,Drug Resistance, Viral ,medicine ,Humans ,NS5B ,Hepatology ,Gastroenterology ,virus diseases ,Hepatitis C, Chronic ,Virology ,digestive system diseases ,Pibrentasvir ,Ombitasvir ,030104 developmental biology ,Amino Acid Substitution ,chemistry ,Benzimidazoles ,Drug Therapy, Combination ,030211 gastroenterology & hepatology ,Carbamates ,medicine.drug - Abstract
Background & Aims Chronic liver diseases caused by hepatitis C virus (HCV) genotype 6 are prevalent in Asia, and millions of people require treatment with direct-acting antiviral regimens, such as NS5A inhibitor velpatasvir combined with the NS5B polymerase inhibitor sofosbuvir. We developed infectious cell culture models of HCV genotype 6a infection to study the effects of these inhibitors and the development of resistance. Methods The consensus sequences of strains HK2 (MG717925) and HK6a (MG717928), originating from serum of patients with chronic HCV infection, were determined by Sanger sequencing of genomes amplified by reverse-transcription polymerase chain reaction. In vitro noninfectious full-length clones of these 6a strains were subsequently adapted in Huh7.5 cells, primarily by using substitutions identified in JFH1-based Core-NS5A and Core-NS5B genotype 6a recombinants. We studied the efficacy of NS5A and NS5B inhibitors in concentration-response assays. We examined the effects of long-term culture of Huh7.5 cells incubated with velpatasvir and sofosbuvir singly or combined following infection with passaged full-length HK2 or HK6a recombinant viruses. Resistance-associated substitutions (RAS) were identified by Sanger and next-generation sequencing, and their effects on viral fitness and in drug susceptibility were determined in reverse-genetic experiments. Results Adapted full-length HCV genotype 6a recombinants HK2cc and HK6acc had fast propagation kinetics and high infectivity titers. Compared with an HCV genotype 1a recombinant, HCV genotype 6a recombinants of strains HK2 and HK6a were equally sensitive to daclatasvir, elbasvir, velpatasvir, pibrentasvir, and sofosbuvir, but less sensitive to ledipasvir, ombitasvir, and dasabuvir. Long-term exposure of HCV genotype 6a-infected Huh7.5 cells with a combination of velpatasvir and sofosbuvir resulted in clearance of the virus, but the virus escaped the effects of single inhibitors via emergence of the RAS L31V in NS5A (conferring resistance to velpatasvir) and S282T in NS5B (conferring resistance to sofosbuvir). Engineered recombinant genotype 6a viruses with single RAS mediated resistance to velpatasvir or sofosbuvir. HCV genotype 6a viruses with RAS NS5A-L31V or NS5B-S282T were however, able to propagate and escape in Huh7.5 cells exposed to the combination of velpatasvir and sofosbuvir. Further, HCV genotype 6a with NS5A-L31V was able to propagate and escape in the presence of pibrentasvir with emergence of NS5A-L28S, conferring a high level of resistance to this inhibitor. Conclusions Strains of HCV genotype 6a isolated from patients can be adapted to propagate in cultured cells, permitting studies of the complete life cycle for this important genotype. The combination of velpatasvir and sofosbuvir is required to block propagation of original HCV genotype 6a, which quickly becomes resistant to single inhibitors via the rapid emergence and persistence of RAS. These features of HCV genotype 6a could compromise treatment.
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- 2018
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36. Urocanic acid-modified chitosan-mediated p53 gene delivery inducing apoptosis of human hepatocellular carcinoma cell line HepG 2 is involved in its antitumor effect in vitro and in vivo
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Yi-ping Li, Lei Tao, Yun Lu, Jing Yao, Wei Wang, Jianping Zhou, and Yu Wang
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Carcinoma, Hepatocellular ,Genetic enhancement ,Biophysics ,Apoptosis ,Biology ,Gene delivery ,Transfection ,Biochemistry ,chemistry.chemical_compound ,In vivo ,Cell Line, Tumor ,Humans ,DAPI ,Molecular Biology ,Cell Proliferation ,Chitosan ,Cell growth ,Liver Neoplasms ,Urocanic Acid ,Genetic Therapy ,Cell Biology ,Molecular biology ,chemistry ,Cell culture ,Cancer research ,Tumor Suppressor Protein p53 - Abstract
The p53 tumor suppressor gene is the most frequently mutated gene identified in many tumors, including hepatocellular carcinoma (HCC). Gene therapy using the p53 gene has been proposed and performed with inactivation of p53 function. However, there have been few reports of nonviral vector-mediated p53 gene delivery in HCC. In this study, the wild-type p53 (wt-p53) gene was transfected into human hepatocellular carcinoma cell line HepG(2) using the urocanic acid-modified chitosan (UAC) as a nonviral vector, and transfection efficiency was determined by FACS analysis. UAC-mediated p53 transfection in HepG(2) cells resulted in high expression levels of wt-p53 mRNA and protein and significant cellular growth inhibition. DAPI staining and Annexin V/PI double-staining assay revealed apoptosis occurrence in HepG(2) cells after treatment with UAC/pEGFP-p53 complexes. In in vivo studies, intratumoral injection of UAC/pEGFP-p53 complexes into BALB/c nude mice bearing HepG(2) cells clearly suppressed tumor growth, and significantly induced apoptosis. These results demonstrated that UAC-mediated efficient p53 gene transfer could induce apoptosis thereby significantly inhibiting the growth of HepG(2) cells in vitro and in vivo, and suggested that UAC-mediated p53 gene delivery might be a promising approach for HCC gene therapy.
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- 2008
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37. Low intensity pulsed ultrasound accelerates macrophage phagocytosis by a pathway that requires actin polymerization, Rho, and Src/MAPKs activity
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Hans J. Gross, Andreas Schmelz, Shaoxia Zhou, Thomas Seufferlein, Yi-ping Li, and Max G. Bachem
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rho GTP-Binding Proteins ,MAPK/ERK pathway ,Cytochalasin D ,Time Factors ,RHOA ,Pyridines ,Phagocytosis ,Low-intensity pulsed ultrasound ,p38 Mitogen-Activated Protein Kinases ,Cell Line ,Mice ,chemistry.chemical_compound ,Escherichia coli ,Animals ,Humans ,Ultrasonics ,Extracellular Signal-Regulated MAP Kinases ,Complement Activation ,Protein Kinase Inhibitors ,Cells, Cultured ,rho-Associated Kinases ,biology ,Kinase ,Macrophages ,Imidazoles ,Cell Biology ,Amides ,Actins ,Cell biology ,src-Family Kinases ,chemistry ,biology.protein ,Mitogen-Activated Protein Kinases ,rhoA GTP-Binding Protein ,Tyrosine kinase ,Signal Transduction ,Proto-oncogene tyrosine-protein kinase Src - Abstract
Phagocytosis is an essential event in the complex process of tissue repair. Here we examined the effect of low intensity pulsed ultrasound (US), which promotes fracture and wound healing, on phagocytosis by mouse macrophage cell line J774A.1 and human monocyte-derived macrophages. First, 10 to 40 min low intensity pulsed US increased uptake of serum opsonized E. coli by J774A.1 cells during a 50 min phagocytosis period. In addition, when the E. coli exposure time was varied between 35 to 80 min, the maximum increase in phagocytosis was observed in the first 35 min upon US exposure. In parallel, US induced robust actin polymerization in a time dependent manner in J774A.1 cells, showing the peak effect 30 min after stimulation. Interestingly, a low concentration of cytochalasin D (0.25-0.5 microM) prevented US-induced phagocytosis of E. coli. Furthermore, we demonstrated US enhanced activation of RhoA. Blocking its downstream effector Rho associated kinase (ROCK) with Y27632 abrogated US-induced phagocytosis. We also show that US induced activation of ERK and p38 MAPK. Pretreatment of the cells with the corresponding inhibitors PD98059 and SB203580 reduced US-induced phagocytosis. In addition, activity of tyrosine kinase Src was required for US-induced phagocytosis. Here Src represents an upstream activator of ERK and p38 MAPK. Depolymerization of actin by cytochalasin D prevented US-induced Src, ERK, and p38 activation. Our data provide a new insight into the cellular and molecular mechanisms by which low intensity pulsed US promotes tissue repair.
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- 2008
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38. Relative quantification and detection of different types of infectious bursal disease virus in bursa of Fabricius and cloacal swabs using real time RT-PCR SYBR green technology
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Mette Kusk, Susanne Kabell, Poul Henrik Jørgensen, Kurt Handberg, Yi-Ping Li, and M.F. Zhang
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animal structures ,Viral pathogenesis ,Virulence ,Biology ,Infectious bursal disease virus ,Virus ,Infectious bursal disease ,Bursa of Fabricius ,Cloaca ,RNA, Ribosomal, 28S ,medicine ,Animals ,Poultry Diseases ,Fluorescent Dyes ,General Veterinary ,Reverse Transcriptase Polymerase Chain Reaction ,Ribosomal RNA ,medicine.disease ,Virology ,Actins ,Specific Pathogen-Free Organisms ,Real-time polymerase chain reaction ,Chickens ,Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+) ,Viral load - Abstract
In present study, different types of infectious bursal disease virus (IBDV), virulent strain DK01, classic strain F52/70 and vaccine strain D78 were quantified and detected in infected bursa of Fabricius (BF) and cloacal swabs using quantitative real time RT-PCR with SYBR green dye. For selection of a suitable internal control gene, real time PCR parameters were evaluated for three candidate genes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 28S rRNA and beta-actin to IBDVs. Based on this beta-actin was selected as an internal control for quantification of IBDVs in BF. All BF samples with D78, DK01 or F52/70 inoculation were detected as virus positive at day 1 post inoculation (p.i.). The D78 viral load peaked at day 4 and day 8 p.i., while the DK01 and F52/70 viral load showed relatively high levels at day 2 p.i. In cloacal swabs, viruses detectable were at day 2 p.i. for DK01 and F52/70, day 8 p.i. for D78. Importantly, the primers set were specific as the D78 primer set gave no amplification of F52/70 and DK01 and the DK01 primer set gave no amplification of D78, thus DK01 and D78 could be quantified simultaneously in dually infected chickens by use of these two set of primers. The method described here is robust and may sever as a useful tool with high capacity for diagnostics as well as in viral pathogenesis studies.
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- 2007
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39. Transactivated minimal E1b promoter is capable of driving the expression of short hairpin RNA
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Fangjun Jia, Li-He Guo, Mei Huang, Yuan-Chang Yan, and Yi-Ping Li
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Gene Expression Regulation, Viral ,Transcriptional Activation ,viruses ,Molecular Sequence Data ,RNA polymerase II ,Adenovirus E1B protein ,Small hairpin RNA ,Viral Proteins ,Transactivation ,RNA interference ,Transcription (biology) ,Virology ,Humans ,Inducer ,RNA, Small Interfering ,Adenovirus E1B Proteins ,Promoter Regions, Genetic ,Base Sequence ,biology ,Promoter ,Molecular biology ,biology.protein ,RNA, Viral ,RNA Interference ,RNA Polymerase II ,HeLa Cells - Abstract
The strategy that transcribes short hairpin RNAs (shRNAs) by RNA polymerase II promoters is expected to present flexible approaches for regulating the patterns of shRNA expression. The capacity of generating shRNA by a modified adenovirus RNA polymerase II E1b promoter was studied. This 49bp promoter consists of a TATA-box and an initiation element. It is demonstrated that this modified E1b promoter is capable of driving shRNA transcription and causing either long-term suppression against the target gene in response to the transactivation of constitutively expressed Gal4-VP16 fusion protein or inducible suppression given that the expression of Gal4-VP16 is subject to a dexamethasone inducer.
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- 2006
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40. Prediction of automotive engine power and torque using least squares support vector machines and Bayesian inference
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Pak Kin Wong, Yi-Ping Li, and Chi-Man Vong
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Engine power ,Automotive engine ,Dynamometer ,Computer science ,Tune-up ,Least squares ,Automotive engineering ,Power (physics) ,Support vector machine ,Artificial Intelligence ,Control and Systems Engineering ,Torque ,Electrical and Electronic Engineering ,Simulation - Abstract
Automotive engine power and torque are significantly affected with effective tune-up. Current practice of engine tune-up relies on the experience of the automotive engineer. The engine tune-up is usually done by trial-and-error method, and then the vehicle engine is run on the dynamometer to show the actual engine output power and torque. Obviously, the current practice costs a large amount of time and money, and may even fail to tune up the engine optimally because a formal power and torque model of the engine has not been determined yet. With an emerging technique, least squares support vector machines (LS-SVM), the approximated power and torque model of a vehicle engine can be determined by training the sample data acquired from the dynamometer. The number of dynamometer tests for an engine tune-up can therefore be reduced because the estimated engine power and torque functions can replace the dynamometer tests to a certain extent. Besides, Bayesian framework is also applied to infer the hyperparameters used in LS-SVM so as to eliminate the work of cross-validation, and this leads to a significant reduction in training time. In this paper, the construction, validation and accuracy of the functions are discussed. The study shows that the predicted results using the estimated model from LS-SVM are good agreement with the actual test results. To illustrate the significance of the LS-SVM methodology, the results are also compared with that regressed using a multilayer feed forward neural networks.
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- 2006
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41. Diapause development and acclimation regulating enzymes associated with glycerol synthesis in the Shonai ecotype of the rice stem borer larva, Chilo suppressalis walker
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Lei Ding, Michiyo Goto, Yi-Ping Li, and Hisaaki Tsumuki
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Glycogen ,Physiology ,fungi ,Diapause ,Biology ,Chilo suppressalis ,biology.organism_classification ,Acclimatization ,Horticulture ,Glycogen phosphorylase ,chemistry.chemical_compound ,chemistry ,Insect Science ,Glyceraldehyde ,Botany ,Glycerol ,Cold acclimation - Abstract
Overwintering larvae of the Shonai ecotype of the rice stem borer, Chilo suppressalis, enter diapause in early September and terminate diapause at the end of October. Cold acclimation at 0 degrees C did not influence glycerol, trehalose or glycogen content in larvae collected on 22 September. Acclimation at 0 degrees C increased the glycerol content and reduced the glycogen content significantly in larvae collected on 2 October and 22 November compared with acclimation at 15 degrees C. These results indicate that overwintering larvae at different phases of diapause development respond differently to the low temperature stimulus for glycerol synthesis. Thus, we evaluated the metabolic rearrangements associated with glycerol synthesis during diapause development and after temperature acclimation. Larvae collected on 2 October were acclimated at 15 degrees C for 15 and 60 days. Some of those acclimated at 15 degrees C were then moved to 0 degrees C for 15 days. The larvae acclimated at 15 degrees C for 15 days were in deep diapause and accumulated little glycerol, while larvae acclimated at 15 degrees C for 60 days were nearly ready to emerge from diapause and accumulated glycerol at 155.5mgr;mol/g. When larvae acclimated to 15 degrees C for 15 days were transferred to 0 degrees C, glycerol accumulation was stimulated to the same extent (ca 140mgr;mol/g) as it was in larvae that were acclimated to 15 degrees C for 60 days and then transferred to 0 degrees C. These results indicate that low temperature has a cumulative effect on glycerol production in larvae at different phases of diapause development. Glycerol accumulation was accomplished by activation of glycogen phosphorylase and inhibition of fructose-1,6-bisphosphatase, and activation of enzymes associated with glycerol synthesis, mainly glyceraldehyde-3-phosphatase and polyol dehydrogenase with glyceraldehyde activity.
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- 2002
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42. Physiology of diapause and cold hardiness in the overwintering pupae of the fall webworm Hyphantria cunea (Lepidoptera: Arctiidae) in Japan
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Yi-Ping Li, S Ito, N Goto, K Sasaki, Michiyo Goto, and Y Sato
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biology ,Physiology ,Diapause ,biology.organism_classification ,Acclimatization ,Trehalose ,Pupa ,Horticulture ,chemistry.chemical_compound ,chemistry ,Insect Science ,Botany ,Hyphantria ,Respiration rate ,Hardiness (plants) ,Overwintering - Abstract
The fall webworm Hyphantria cunea Drury, which was accidentally introduced to Japan in 1945, overwinters on the ground in pupal diapause. Diapause termination, as indicated by the respiration rate and the period required for adult emergence, began in March and ended in April. Cold hardiness (the ability to survive exposure to -15 degrees C) decreased linearly with diapause development from November to the following April under field conditions. Cold hardiness of diapause pupae (DP) decreased as the acclimation temperature decreased from 15 to -10 degrees C, whereas cold hardiness of non-diapause pupae (NDP) remained high as the acclimation temperature decreased from 5 to -5 degrees C. However, H. cunea in Japan can survive exposure to -5 degrees C for two weeks, whether it is in a diapause or non-diapause state. Trehalose was the main sugar detected in the body, but its level was less than 0.8%. Trehalose levels increased in field-collected pupae from January to March. DP accumulated less trehalose than NDP, as the acclimation temperature was decreased from 5 to -5 degrees C. The alanine content in field-collected pupae increased from November to February. Both diapause and low temperature caused an accumulation of alanine. These results suggest that under field conditions, overwintering pupae of H. cunea in Japan do not accumulate high levels of sugars and polyols and do not develop a high level of cold hardiness. Furthermore, DP do not accumulate high levels of sugars and polyols and their ability to survive exposure to -15 degrees C is not greater than that of NDP. The physiological and biochemical bases of diapause in H. cunea from Japan are discussed.
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- 2001
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43. Cold hardiness in summer and winter diapause and post-diapause pupae of the cabbage armyworm, Mamestra brassicae L. under temperature acclimation
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Shinichi Outani, Koichi Suzuki, Michiyo Goto, Yi-Ping Li, and Shirou Kayaba
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Physiology ,Diapause ,Biology ,Acclimatization ,Trehalose ,Mamestra brassicae ,Pupa ,Horticulture ,chemistry.chemical_compound ,chemistry ,Insect Science ,Botany ,Hemolymph ,Cold acclimation ,Hardiness (plants) - Abstract
Cold hardiness and biochemical changes were investigated in winter and summer pupae of the cabbage armyworm Mamestra brassicae at the diapause and post-diapause stages under temperature acclimation. Diapause pupae were successively acclimated to 25, 20 and then 10 degrees C (warm-acclimated group). Pupae at the diapause and post-diapause stages were successively acclimated to 5, 0, -5 and then -10 degrees C (cold-acclimated groups). Supercooling point values in winter and summer pupae remained constant regardless of the diapause stages and acclimated temperatures. Warm-acclimated pupae at the diapause stage did not survive the subzero temperature exposure, whereas, cold-acclimated pupae achieved cold hardiness to various degrees. Winter pupae were more cold hardy than summer pupae, and pupae at the post-diapause stage were more cold hardy than those at the diapause stage. Trehalose contents in winter pupae rose under cold acclimation. Summer pupae accumulated far lower trehalose contents than winter pupae, with the maximal level occurring in winter pupae at the post-diapause stage. Glycogen content remained at a high level in diapause pupae after warm acclimation, whereas it decreased after cold acclimation. Alanine, the main free amino acid in haemolymph after cold acclimation, increased at lower temperatures in both diapause and post-diapause pupae, but the increase was greater in the diapause pupae. These results suggest that cold hardiness is more fully developed in winter pupae than in summer pupae, and cold acclimation provides higher cold hardiness in winter pupae at the post-diapause stage than at the diapause stage.
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- 2001
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44. Slow Pelleting Coagulation of MBS Latex
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Gaixia Xu, Kuanglei Wang, Yi-Ping Li, and Ming Chen
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chemistry.chemical_classification ,Aqueous solution ,Chemistry ,General Chemical Engineering ,Mineralogy ,General Chemistry ,Polymer ,Residence time (fluid dynamics) ,Styrene ,chemistry.chemical_compound ,Chemical engineering ,Coagulation (water treatment) ,Particle ,Particle size ,Methyl methacrylate - Abstract
In this paper, the continuous slow pelleting coagulation of polymer latex consisting of butadiene, styrene and methyl methacrylate (MBS) was investigated, using H 2 SO 4 aqueous solution as coagulant. The effects of pH, temperature, feeding mode, agitation, polymer concentration and residence time on coagulation were discussed. It was found that spherical particles with uniform particle size and high bulk density were produced in the narrow range of pH. In order to obtain good particle morphology and high bulk density, welldistributed concentration, temperature and shear field in the coagulating system were required. The research will not only provide a basis for the design and production of MBS but also propose a new method for continuous pelleting coagulation.
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- 1997
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45. ZIP4 regulates pancreatic cancer cachexia and post-surgical survival through activation of P38 pathway
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Yi-Ping Li, Guohua Zhang, Xiaoling Ni, Jingxuan Yang, Yuqing Zhang, Crag D. Logsdon, and Min Li
- Subjects
Oncology ,medicine.medical_specialty ,Post surgical ,Hepatology ,business.industry ,Endocrinology, Diabetes and Metabolism ,p38 mitogen-activated protein kinases ,Gastroenterology ,medicine.disease ,Cachexia ,Internal medicine ,Pancreatic cancer ,medicine ,business - Published
- 2016
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46. A cell type-specific silencer in the human choline acetyltransferase gene requiring two distinct and interactive E boxes
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Richard Davis, Fred Baskin, Yi-Ping Li, Louis B. Hersh, and Donghai Wu
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Neurons ,Regulation of gene expression ,Mutation ,Base Sequence ,Molecular Sequence Data ,E-box ,Regulatory Sequences, Nucleic Acid ,Biology ,medicine.disease_cause ,Silencer ,Choline acetyltransferase ,Molecular biology ,Choline O-Acetyltransferase ,Neuroblastoma ,Cellular and Molecular Neuroscience ,Gene Expression Regulation ,Regulatory sequence ,Tumor Cells, Cultured ,medicine ,Humans ,Cholinergic ,Nuclear protein ,DNA Probes ,Molecular Biology - Abstract
We have previously reported that cholinergic neuron-specific expression of the human choline acetyltransferase gene is mediated by two co-operative silencers. We have now localized the proximal silencer to the region from nucleotide −2195 to −2409, which contains two distinct E boxes (CACCTG and CATGTG). Deletion or mutation of either of these E boxes results in a loss of silencer activity. There are specific nuclear proteins in adrenergic cells which bind to each of the two E boxes. However, nuclear proteins from cholinergic cells only bind the 5′ E box not the 3′ E box. It is this interaction which appears to be the cause of the inactivity of this silencer in these cells.
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- 1995
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47. Unloading of the heart in vivo rapidly activates markers of the ubiquitin proteosome proteolytic pathway and mTOR pathway
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Peter Razeghi, Stanislaw M. Stepkowski, Yi-Ping Li, Jun Ying, Saumya Sharma, Heinrich Taegtmeyer, O.H. Frazier, and Micheal B. Reid
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Proteasome ,Biochemistry ,Ubiquitin ,biology ,In vivo ,business.industry ,biology.protein ,Medicine ,Cardiology and Cardiovascular Medicine ,business ,PI3K/AKT/mTOR pathway ,Cell biology - Published
- 2003
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48. Evaluation of tussilagone: A cardiovascular-respiratory stimulant isolated from Chinese herbal medicine
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Yun-mo Wang and Yi-ping Li
- Subjects
Male ,Dopamine ,Tussilagone ,Stimulation ,Pharmacology ,Tachyphylaxis ,Median lethal dose ,Lethal Dose 50 ,Mice ,Dogs ,Heart Rate ,Drug Discovery ,Respiration ,medicine ,Animals ,Anesthesia ,Respiratory system ,CATS ,biology ,Dose-Response Relationship, Drug ,Traditional medicine ,Terpenes ,business.industry ,Hemodynamics ,biology.organism_classification ,Dose–response relationship ,Tussilago ,Injections, Intravenous ,Cats ,Female ,business ,Sesquiterpenes ,Drugs, Chinese Herbal ,medicine.drug - Abstract
1. Traditional Chinese herbal medicine has long used Kuandong Hua (Tussilago farfara L.) in the treatment of various respiratory conditions. 2. Recently, it has been found that an extract of this plant (7R,14R)-14-acetoxy-7-[(2'E)-3'-methylpent-2'-enoyloxy ]-oplopanone, is a potent cardiovascular and respiratory stimulant. 3. This compound has been named Tussilagone (TUS) and when administered intravenously, has been shown to produce an instant and dose dependent pressor effect in anesthetized dogs (0.02-0.3 mg/kg), cats (0.02-0.5 mg/kg), and rats (0.4-4 mg/kg). 4. This pressor effect is similar to that of dopamine; however, no tachyphylaxis has been observed. 5. In addition to its cardiovascular effects TUS produced a significant stimulation of respiration in experimental animals. 6. The acute intravenous LD50 in mice of this compound was 28.9 mg/kg.
- Published
- 1988
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