103 results on '"Ke Tian"'
Search Results
2. Real-World Oriented Smartphone AR Supported Learning System Based on Planetarium Contents for Seasonal Constellation Observation
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Ke Tian, Mayu Urata, Mamoru Endo, Katsuhiro Mouri, Takami Yasuda, and Jien Kato
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augmented reality ,smartphone ,seasonal constellation ,astronomy education ,planetarium contents ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A popular astronomical concept covered by projection learning programs in the planetarium is seasonal constellation. However, a planetarium’s learning environment is limited to virtual scenes, where learners can observe seasonal constellations, but there is a significant difference between reality and the learners’ imagination regarding constellations. It is important to create a real-world oriented observation learning environment for observing seasonal constellations. Augmented reality has proved to be a powerful tool for astronomical observation learning. In this paper, augmented reality (AR) contents and 2D contents are used to develop a smartphone-based learning system called the Real-World Oriented Smartphone AR Learning System (R-WOSARLS) for seasonal constellation observation, which is based on the planetarium contents of the planetarium of the Nagoya City Science Museum, for seasonal constellation learning. Two experiments were conducted to evaluate the usefulness, usability, and learner satisfaction of our system in university and junior high school, respectively. The results show that R-WOSARLS is an effective learning tool for constellation observation and learning, and it enhances learners’ motivation to pursue seasonal constellation learning. Moreover, R-WOSARLS could be a teaching tool not only to help students learn more than with traditional instruction, but also to stimulate their interest in astronomical phenomena outside of school.
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- 2019
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3. Study on Components Determination and Performance Evaluation of LS Pre-Maintenance Agent
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Yuxiang Tian, Biao Ma, Ke Tian, Ning Li, and Xueyan Zhou
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highway engineering ,light screening preventive maintenance agent ,optimum proportion ,permeability ,restore performance ,light aging resistance ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Adequate maintenance and taking active preventive measures can effectively prevent the early disease of asphalt pavements before significant damage occurs. By developing a light screening preventive maintenance agent (LS pre-maintenance agent) for strong ultraviolet (UV) radiation areas, based on the asphalt aging and regeneration mechanism, we analyzed the function and basic components and determined the optimum components ratio based on the best proportion of penetrant and solvent oil for solubility. The optimum ratio for quick-drying and long-term storage ability is the mass ratio of rock asphalt, reducing agent, penetrant, and solvent oil, which is 30:20:20:30. The light-shield agent is 5% of the total mass of the rock asphalt, reducing agent, penetrant, and solvent oil, and the dispersant is 0.4%. Digital image technology was used to provide an accurate measurement of the LS pre-maintenance agent penetration depth, evaluate its permeability and reasonable amount. We then used the rolling thin film oven test (RTFOT) to analyze its effect on aged asphalt and evaluated the restoration performance. Using the strong UV radiation aging test, we analyzed its anti-light aging performance. The results showed that pavement must be closed at least 2 h after the brushing LS pre-maintenance agent has been applied and this can be extended to upwards of 8 h time permitting. A dosage of 0.5 kg/m2 can ensure sufficient penetration depth and curing effect. Furthermore, the agent shows excellent restorative and anti-light aging abilities, which can effectively improve the low-temperature performance of aged asphalt and meet the pre-maintenance requirements for asphalt pavement, especially in strong UV radiation areas.
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- 2018
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4. A novel NUP98-JADE2 fusion in a patient with acute myeloid leukemia resembling acute promyelocytic leukemia
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Chi Kong Li, Hoi-Yun Chan, Joyce S. Cheung, Chi Keung Cheng, Natalie Ph Chan, Margaret Hl Ng, Thomas Sk Wan, Yuk-Lin Yung, Alex Wing Kwan Leung, and Ke Tian
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Acute promyelocytic leukemia ,Myeloid ,Receptors, Retinoic Acid ,Retinoic acid ,Tretinoin ,Pathogenesis ,chemistry.chemical_compound ,Immunophenotyping ,Leukemia, Promyelocytic, Acute ,immune system diseases ,medicine ,Transcriptional regulation ,Humans ,Child ,neoplasms ,Gene ,business.industry ,Myeloid leukemia ,Hematology ,medicine.disease ,Nuclear Pore Complex Proteins ,Leukemia, Myeloid, Acute ,medicine.anatomical_structure ,chemistry ,Cancer research ,Exceptional Case Report ,business - Abstract
Key Points Non-RAR gene rearrangements have been associated with patients with AML resembling APL but the underlying pathogenesis is unclear.NUP98-JADE2 perturbs wild-type JADE2 and retinoic acid signaling thereby contributing to an APL-like phenotype., Acute promyelocytic leukemia (APL) is a specific subtype of acute myeloid leukemia (AML) characterized by block of differentiation at the promyelocytic stage and the presence of PML-RARA fusion. In rare instances, RARA is fused with other partners in variant APL. More infrequently, non-RARA genes are rearranged in AML patients resembling APL. However, the underlying disease pathogenesis in these atypical cases is largely unknown. Here, we report the identification and characterization of a NUP98- JADE2 fusion in a pediatric AML patient showing APL-like morphology and immunophenotype. Mechanistically, we showed that NUP98-JADE2 could impair all-trans retinoic acid (ATRA)-mediated transcriptional control and myeloid differentiation. Intriguingly, NUP98-JADE2 was found to alter the subcellular distribution of wild-type JADE2, whose down-regulation similarly led to attenuated ATRA-induced responses and myeloid activation, suggesting that NUP98-JADE2 may mediate JADE2 inhibition. To our knowledge, this is the first report of a NUP98-non-RAR rearrangement identified in an AML patient mimicking APL. Our findings suggest JADE2 as a novel myeloid player involved in retinoic acid-induced differentiation. Despite lacking a rearranged RARA, our findings implicate that altered retinoic acid signaling by JADE2 disruption may underlie the APL-like features in our case, corroborating the importance of this signaling in APL pathogenesis.
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- 2022
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5. Fe3+ Promoted the Photocatalytic Defluorination of Perfluorooctanoic Acid (PFOA) over In2O3
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Dongle Cheng, Derek Hao, Liwu Zhang, Ke Tian, Feng Zhu, Wei Wei, Bing-Jie Ni, Xiaoqing Liu, and Zhijie Chen
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Chemistry ,02 engineering and technology ,010501 environmental sciences ,021001 nanoscience & nanotechnology ,01 natural sciences ,3. Good health ,law.invention ,chemistry.chemical_compound ,Chemistry (miscellaneous) ,law ,Photocatalysis ,Environmental Chemistry ,Chemical Engineering (miscellaneous) ,Perfluorooctanoic acid ,Calcination ,0210 nano-technology ,Photocatalytic degradation ,0105 earth and related environmental sciences ,Water Science and Technology ,Nuclear chemistry - Abstract
In this study, four kinds of In2O3 photocatalysts were prepared by a facile calcination process at different temperatures and used for the removal of perfluorooctanoic acid (PFOA) from contaminated...
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- 2021
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6. Optical detection of ammonia in water using integrated up-conversion fluorescence in a fiberized microsphere
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Libo Yuan, Meng Zhang, Jibo Yu, Ruoning Wang, Gilberto Brambilla, Ke Tian, and Pengfei Wang
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Phenol red ,Microsphere ,Aqueous solution ,Materials science ,integrated device ,Analytical chemistry ,up-conversion ,Fluorescence ,Atomic and Molecular Physics, and Optics ,Ion ,Ammonia ,chemistry.chemical_compound ,chemistry ,pH indicator ,Fiber ,Absorption (electromagnetic radiation) ,optical ammonia sensor - Abstract
A novel optical sensor for ammonia concentration in water is demonstrated using up-conversion (UC) fluorescence intensity ratio (FIR). The sensor element consists of (i) an Er 3+ -Yb 3+ co-doped tellurite glass microsphere integrated inside a section of suspended tri-core hollow fiber (STCHF) and (ii) the pH indicator phenol red. When 980 nm pump is coupled into the microsphere, the Er 3+ ions produce green and red UC emissions. Exposure to ammonia results in a strong increase in the 560 nm absorption of the phenol red, which acts as a filter for the green emission, while the red emission is unaffected. A simple linear relation between the FIR and the ammonia aqueous concentration has been established.
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- 2021
7. Preparation of Flower-like CuFe2O4 by a Self-Templating Method for High-Efficient Activation of Peroxymonosulfate To Degrade Carbamazepine
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Hong Jiang, Shun-Feng Jiang, Lu−Lu Wang, Ke Tian, and Wei-Fei Hu
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Chemistry ,General Chemical Engineering ,Flower like ,medicine ,General Chemistry ,Carbamazepine ,Combinatorial chemistry ,Industrial and Manufacturing Engineering ,medicine.drug - Published
- 2021
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8. Donor–acceptor structure of a coordination polymer with long-lived room temperature phosphorescence and angle-dependent polarized emission
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Ji-Rui Zhang, Wen-Jing Qin, Xu-Ke Tian, Xiao-Gang Yang, and Yuming Guo
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chemistry.chemical_compound ,Materials science ,chemistry ,Orders of magnitude (temperature) ,Coordination polymer ,General Materials Science ,Phosphor ,General Chemistry ,Condensed Matter Physics ,Phosphorescence ,Donor acceptor ,Photochemistry - Abstract
A new strategy to achieve long-lived room temperature phosphorescence performance has been developed via the formation of a donor–acceptor structure in a coordination polymer, which features a lifetime (40.22 ms) three orders of magnitude higher than that of pristine phosphor. It also shows remarkable angle-dependent polarized emission.
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- 2021
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9. MicroRNA-125b exerts antitumor functions in cutaneous squamous cell carcinoma by targeting the STAT3 pathway
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Wanggen Liu, Guoying Miao, Chunxia Yao, Jing Zhang, Jingyuan Liu, Nan Zhao, Ke Tian, and Xiaoyi Fan
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STAT3 Transcription Factor ,Skin Neoplasms ,Apoptosis ,Biochemistry ,Flow cytometry ,Cyclin D1 ,Downregulation and upregulation ,Cell Line, Tumor ,medicine ,Research Letter ,Humans ,MTT assay ,lcsh:QH573-671 ,STAT3 ,Molecular Biology ,Signal transducer and activator of transcription (STAT) 3 ,Cell Proliferation ,medicine.diagnostic_test ,biology ,Cell growth ,Chemistry ,lcsh:Cytology ,microRNA-125b ,Cell Biology ,Cutaneous squamous cell carcinoma ,Molecular medicine ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,Proto-Oncogene Proteins c-bcl-2 ,Cancer research ,STAT protein ,biology.protein ,Carcinoma, Squamous Cell ,Signal Transduction - Abstract
Background MicroRNA-125b (miR-125b) is downregulated in human cutaneous squamous cell carcinoma (CSCC). However, its function in CSCC has yet to be extensively explored. Here, we analyze the relationship between signal transducer and activator of transcription 3 (STAT3) and miR-125b in CSCC. Methods Western blotting and quantitative RT-PCR were used to determine the expression of the miR-125b–STAT3 axis in human CSCC tissues and cell lines. The direct regulatory effect of miR-125b on STAT3 expression was assessed using a luciferase reporter gene assay and RNA immunoprecipitation assay. The MTT assay and flow cytometry were used to determine the role of the miR-125b–STAT3 axis in CSCC cell proliferation and apoptosis. Results MiR-125b expression levels were significantly lower in CSCC cell lines and tissues than in normal cell lines and tissues. STAT3 was identified as the direct target of miR-125b. Upregulation of miR-125b and downregulation of STAT3 suppressed cell proliferation and promoted cell apoptosis. Cyclin D1 and Bcl2 were identified as the downstream targets of the miR-125–STAT3 axis. Conclusions Our findings indicate that miR-125b acts as a tumor suppressor in CSCC by targeting the STAT3 pathway. This observation increases our understanding of the molecular mechanisms of CSCC. Therapies aimed at activating miR-125b or inhibiting STAT3 signaling should be explored as potential treatments for CSCC.
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- 2020
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10. Nrf2 activation ameliorates mechanical allodynia in paclitaxel-induced neuropathic pain
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Xiao-Mei Wang, Jia Sun, Fei Cao, Shu-Ping Chen, Nan Chen, Yu-Ke Tian, Dai-Qiang Liu, Da-Wei Ye, and Ya-Qun Zhou
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0301 basic medicine ,Paclitaxel ,NF-E2-Related Factor 2 ,medicine.medical_treatment ,Intraperitoneal injection ,HO-1 ,Endogeny ,Thiophenes ,Pharmacology ,medicine.disease_cause ,Article ,Nrf2 ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Alkaloids ,Oltipraz ,medicine ,oxidative stress ,Animals ,Pharmacology (medical) ,neuropathic pain ,Analgesics ,Cumulative dose ,business.industry ,Thiones ,General Medicine ,Spinal cord ,Rats ,Up-Regulation ,030104 developmental biology ,Nociception ,medicine.anatomical_structure ,chemistry ,Spinal Cord ,Hyperalgesia ,030220 oncology & carcinogenesis ,oltipraz ,Pyrazines ,Neuropathic pain ,Heme Oxygenase (Decyclizing) ,Neuralgia ,business ,Oxidative stress - Abstract
Paclitaxel-induced neuropathic pain (PINP) is refractory to currently used analgesics. Previous studies show a pivotal role of oxidative stress in PINP. Because the nuclear factor erythroid-2-related factor 2 (Nrf2) has been considered as the critical regulator of endogenous antioxidant defense, we here explored whether activation of Nrf2 could attenuate PINP. A rat model of PINP was established by intraperitoneal injection of paclitaxel (2 mg/kg) every other day with a final cumulative dose of 8 mg/kg. Hind paw withdrawal thresholds (PWTs) in response to von Frey filament stimuli were used to assess mechanical allodynia. We showed that a single dose of Nrf2 activator, oltipraz (10, 50, and 100 mg/kg), dose-dependently attenuated established mechanical allodynia, whereas repeated injection of oltipraz (100 mg· kg−1· d−1, i.p. from d 14 to d 18) almost abolished the mechanical allodynia in PINP rats. The antinociceptive effect of oltipraz was blocked by pre-injection of Nrf2 inhibitor trigonelline (20 mg/kg, i.p.). Early treatment with oltipraz (100 mg· kg−1· d−1, i.p. from d 0 to d 6) failed to prevent the development of the PINP, but delayed its onset. Western blot and immunofluorescence analysis revealed that the expression levels of Nrf2 and HO-1 were significantly upregulated in the spinal cord of PINP rats. Repeated injection of oltipraz caused further elevation of the expression levels of Nrf2 and HO-1 in the spinal cord of PINP rats, which was reversed by pre-injection of trigonelline. These results demonstrate that oltipraz ameliorates PINP via activating Nrf2/HO-1-signaling pathway in the spinal cord.
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- 2020
11. Detecting Host-Plant Volatiles with Odorant Receptors from Grapholita molesta (Busck) (Lepidoptera: Tortricidae)
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Aisheng Fang, Li-Hui Chen, Xiang-Li Xu, Weining Cheng, Ke Tian, Jun-Xiang Wu, Guirong Wang, and Wei Liu
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0106 biological sciences ,Tortricidae ,Olfactory system ,biology ,Nonanal ,010401 analytical chemistry ,Zoology ,General Chemistry ,Decanal ,biology.organism_classification ,01 natural sciences ,Grapholita molesta ,0104 chemical sciences ,Lepidoptera genitalia ,chemistry.chemical_compound ,Octanal ,chemistry ,PEST analysis ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
Grapholita molesta is a global pest of stone and pome fruits. The sensitive olfactory system plays a crucial role in regulating key behavioral activities of insects and G. molesta relies heavily on general odorant receptors (ORs) to detect host-plant volatiles. In this study, three general OR genes from G. molesta (GmolOR12, GmolOR20, and GmolOR21) were identified. Quantitative polymerase chain reaction revealed that GmolORs expression was considerably higher in adults and adult antennae than in any other life stages and body parts, respectively. Moreover, the expression of GmolORs was significantly higher in the antennae of females than in those of males, with a peak in the antennae of 3-days-old adult females. GmolOR20 and GmolOR21 displayed no responses to any of the odorant compounds tested in the Xenopus oocyte system. GmolOR12 was tuned mainly to 5 of the 47 odorant components tested (including decanol, heptanal, octanal, nonanal, and decanal), and the response to aldehydes among the 5 components was the highest. Additionally, they all elicited female and male antennae electroantennogram responses, and the aldehydes elicited the highest response among the 5 components. These results suggested that GmolOR12 in the G. molesta olfactory system plays an important role in sensing aldehydes and that GmolOR12 is involved in sensing host-plant volatiles. These findings provide insight into the possibility of using host-plant volatiles for the control of G. molesta.
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- 2020
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12. Effects of the acid–base treatment of corn on rumen fermentation and microbiota, inflammatory response and growth performance in beef cattle fed high-concentrate diet
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Yongjiang Wu, Ke Tian, Jianjun Liu, Juncai Chen, Tianle He, Yawang Sun, Ruiming Zhang, and Guozhong Dong
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food.ingredient ,hydrochloric acid ,040301 veterinary sciences ,sodium bicarbonate ,PH reduction ,Butyrate ,Beef cattle ,SF1-1100 ,steer ,0403 veterinary science ,Rumen ,chemistry.chemical_compound ,Animal science ,food ,Resistant starch ,chemistry.chemical_classification ,Sodium bicarbonate ,lipopolysaccharide ,0402 animal and dairy science ,food and beverages ,04 agricultural and veterinary sciences ,040201 dairy & animal science ,Animal culture ,ruminal bacteria ,chemistry ,Propionate ,Animal Science and Zoology ,Fermentation - Abstract
Beef cattle are often fed high-concentrate diet (HCD) to achieve high growth rate. However, HCD feeding is strongly associated with metabolic disorders. Mild acid treatment of grains in HCD with 1% hydrochloric acid (HA) followed by neutralization with sodium bicarbonate (SB) might modify rumen fermentation patterns and microbiota, thereby decreasing the negative effects of HCD. This study was thus aimed to investigate the effects of treatment of corn with 1% HA and subsequent neutralization with SB on rumen fermentation and microbiota, inflammatory response and growth performance in beef cattle fed HCD. Eighteen beef cattle were randomly allocated to three groups and each group was fed different diets: low-concentrate diet (LCD) (concentrate : forage = 40 : 60), HCD (concentrate : forage = 60 : 40) or HCD based on treated corn (HCDT) with the same concentrate to forage ratio as the HCD. The corn in the HCDT was steeped in 1% HA (wt/wt) for 48 h and neutralized with SB after HA treatment. The animal trial lasted for 42 days with an adaptation period of 7 days. At the end of the trial, rumen fluid samples were collected for measuring ruminal pH values, short-chain fatty acids, endotoxin (or lipopolysaccharide, LPS) and bacterial microbiota. Plasma samples were collected at the end of the trial to determine the concentrations of plasma LPS, proinflammatory cytokines and acute phase proteins (APPs). The results showed that compared with the LCD, feeding the HCD had better growth performance due to a shift in the ruminal fermentation pattern from acetate towards propionate, butyrate and valerate. However, the HCD decreased ruminal pH and increased ruminal LPS release and the concentrations of plasma proinflammatory cytokines and APPs. Furthermore, feeding the HCD reduced bacterial richness and diversity in the rumen. Treatment of corn increased resistant starch (RS) content. Compared with the HCD, feeding the HCDT reduced ruminal LPS and improved ruminal bacterial microbiota, resulting in decreased inflammation and improved growth performance. In conclusion, although the HCD had better growth performance than the LCD, feeding the HCD promoted the pH reduction and the LPS release in the rumen, disturbed the ruminal bacterial stability and increased inflammatory response. Treatment of corn with HA in combination with subsequent SB neutralization increased the RS content and helped counter the negative effects of feeding HCD to beef steers.
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- 2020
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13. A novel rGO-decorated ZnO/BiVO4 heterojunction for the enhancement of NO2 sensing properties
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Aifan Chen, Ke Tian, Shouli Bai, Jian Guo, Ning Han, Dianqing Li, and Ruixian Luo
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Inorganic Chemistry ,chemistry.chemical_compound ,Materials science ,Operating temperature ,chemistry ,Chemical engineering ,Composite number ,Hydrazine ,Heterojunction ,Hydrate ,Rapid response ,Hydrothermal circulation - Abstract
A ZnO/BiVO4 heterojunction has been first prepared by the co-precipitation and hydrothermal methods; then, rGO nanosheets are decorated onto the heterojunction by simple hydrazine hydrate reduction to construct a novel ZnO/BiVO4/rGO composite-based NO2 sensor. The structure, morphology and gas sensing performance of the composite were characterized and measured using various spectroscopies and gas sensing tests. Compared to the same kinds of gas sensors reported previously, this sensor exhibits competitive sensing performance with a maximum response of 126.64 to 1 ppm NO2 at an operating temperature of 95 °C, which is 5.7 times and 2.4 times higher than those of the ZnO and ZnO/BiVO4 junctions, respectively. Also, the sensor shows a rapid response and long-term stability to NO2 compared with pure ZnO. The good sensing properties are ascribed to the formation of the n–n heterojunction between ZnO and BiVO4 and the decoration with rGO.
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- 2020
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14. Water cluster in hydrophobic crystalline porous covalent organic frameworks
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Shanshan Tao, Donglin Jiang, Ke Tian Tan, and Ning Huang
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chemistry.chemical_classification ,Multidisciplinary ,Materials science ,Capillary condensation ,Science ,Nucleation ,General Physics and Astronomy ,General Chemistry ,Polymer ,Microporous material ,Two-dimensional materials ,Article ,General Biochemistry, Genetics and Molecular Biology ,chemistry ,Chemical engineering ,Covalent bond ,Porous materials ,Fluidics ,Water cluster ,Porosity ,Porous medium - Abstract
Progress over the past decades in water confinement has generated a variety of polymers and porous materials. However, most studies are based on a preconception that small hydrophobic pores eventually repulse water molecules, which precludes the exploration of hydrophobic microporous materials for water confinement. Here, we demonstrate water confinement across hydrophobic microporous channels in crystalline covalent organic frameworks. The frameworks are designed to constitute dense, aligned and one-dimensional polygonal channels that are open and accessible to water molecules. The hydrophobic microporous frameworks achieve full occupation of pores by water via synergistic nucleation and capillary condensation and deliver quick water exchange at low pressures. Water confinement experiments with large-pore frameworks pinpoint thresholds of pore size where confinement becomes dominated by high uptake pressure and large exchange hysteresis. Our results reveal a platform based on microporous hydrophobic covalent organic frameworks for water confinement., Research on water confinement in small hydrophobic pores remains scarce because of a preconception that small hydrophobic pores repulse water molecules. Here, the authors demonstrate water confinement across hydrophobic microporous channels in crystalline covalent organic frameworks.
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- 2021
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15. Room-Temperature Phosphorescent Co-Crystal Showing Direct White Light and Photo-Electric Conversion
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Xin Fan, Xu-Ke Tian, Ji-Rui Zhang, Dongpeng Yan, Wen-Jing Qin, Lu-Fang Ma, and Xiao-Gang Yang
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Anthracene ,Photoluminescence ,Materials science ,room temperature phosphorescence ,Exciton ,General Chemistry ,triplet excitons ,Photochemistry ,co-crystal ,Fluorescence ,photoelectric response ,Crystal ,Chemistry ,chemistry.chemical_compound ,chemistry ,Molecule ,Phosphorescence ,QD1-999 ,HOMO/LUMO ,white light ,Original Research - Abstract
The development of molecular crystalline materials with efficient room-temperature phosphorescence has been obtained much attention due to their fascinating photophysical properties and potential applications in the fields of data storage, bioimaging and photodynamic therapy. Herein, a new co-crystal complex [(DCPA) (AD)2] (DCPA = 9,10-di (4-carboxyphenyl)anthracene; AD = acridine) has been synthesized by a facile solvothermal process. Crystal structure analysis reveals that the co-crystal possesses orderly and alternant arrangement of DCPA donors and AD acceptors at molecular level. Fixed by strong hydrogen bonds, the DCPA molecule displays seriously twisty spatial conformation. Density functional theory (DFT) calculations show well separation of HOMO and LUMO for this co-crystal system, suggesting the efficient triplet excitons generation. Photoluminescence measurements show intensive cyan fluorescence (58.20 ns) and direct white phosphorescence (325 µs) emission at room-temperature. The transient current density–time curve reveals a typical switching electric response under the irradiation of simulated light, reveal that the [(DCPA) (AD)2] co-crystal has a high photoelectric response performance.
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- 2021
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16. Hypoxia inducible factor-3α promotes osteosarcoma progression by activating KDM3A-mediated demethylation of SOX9
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Dongdong Meng, Jianzhong Xu, Fang-Gang Bi, Zhifu Li, Jian-Guang Sun, Gu Chenxi, Yong-Yi Liu, Ke Tian, and Yu Li
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Male ,Jumonji Domain-Containing Histone Demethylases ,Apoptosis ,Bone Neoplasms ,Toxicology ,Methylation ,Small hairpin RNA ,Animals ,Humans ,STAT3 ,Transcription factor ,Cell Proliferation ,Gene knockdown ,Mice, Inbred BALB C ,Osteosarcoma ,biology ,Cell growth ,Chemistry ,SOX9 Transcription Factor ,General Medicine ,Lysine demethylase 3A ,Repressor Proteins ,Hypoxia-inducible factors ,Cancer research ,STAT protein ,biology.protein ,Female ,Apoptosis Regulatory Proteins ,Signal Transduction - Abstract
Hypoxia/oxygen-sensing signally is closely associated with many tumor progressions, including osteosarcoma (OS). Previous research principally focused on the function of hypoxia-inducible factor (HIF)-1α and HIF-2α as the major hypoxia-associated transcription factors in OS, however, the role of HIF-3α has not been investigated. Our study found that HIF-3α was upregulated in OS tissues and cell lines. HIF-3α overexpression facilitated cell proliferation and invasion, and inhibited apoptosis, whereas HIF-3α knockdown showed the opposite results. Chromatin immunoprecipitation analysis revealed that lysine demethylase 3A (KDM3A) expression was transcriptionally activated by HIF-3α under hypoxia, and KDM3A occupied the SRY-box transcription factor 9 (SOX9) gene promoter region through H3 lysine 9 dimethylation (H3K9me2). Additionally, rescue results revealed that KDM3A or SOX9 overexpression reversed the effects of HIF-3α silence on cell functions. The Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway inhibitor cucurbitacin I suppressed the promotive effects of HIF-3α overexpression on cell proliferation, invasion and TAK2/STAT3 pathway. Finally, OS cell line MG-63 transfected with HIF-3α short hairpin RNA (HIF-3α shRNA) were subcutaneously injected into nude mice, and the results found that HIF-3α knockdown significantly inhibited the xenograft tumor growth of OS in vivo. In conclusion, this study reveals that HIF-3α promotes OS progression in vitro and in vivo by activating KDM3A-mediated SOX9 promoter demethylation, which may provide a potential therapeutic mechanism for OS.
- Published
- 2021
17. A comparative study of electrical aging of multiwalled carbon nanotubes and carbon black filled cross-linked polyethylene
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Kai Zhou, Pei Yang, Ke Tian, and Xiancheng Ren
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polyethylene ,Electrical aging ,Cross-linked polyethylene ,Materials science ,Nanocomposite ,Mechanical Engineering ,Water effect ,Carbon black ,electrical degradation ,Polyethylene ,Multiwalled carbon ,chemistry.chemical_compound ,TP1080-1185 ,chemistry ,Mechanics of Materials ,electrical properties ,TA401-492 ,Materials Chemistry ,Ceramics and Composites ,Breakdown strength ,Polymers and polymer manufacture ,Composite material ,Materials of engineering and construction. Mechanics of materials ,cross-linking - Abstract
In this work, XLPE/MWCNT and XLPE/CB nanocomposites have been prepared in order to investigate AC electric field and water effects on electrical aging of XLPE. The mechanical, AC breakdown strength and AC conductivity were tested and the morphologies after 30 days electrical aging were observed using an optical microscope. The results showed that all samples exhibit excellent insulation properties and mechanical properties. Compared with CB addition, the MWCNT composites exhibit better resistance to electrical aging, with the length of electrical aging-induced microcracks in the MWCNT blends decreasing from 104 to 22 µm, and the width decreasing from 87 to 17 µm, which means a reduction of ∼80% compared of values for neat XLPE in both length and width. However, the XLPE/CB composites have a tendency to promote electrical aging. The mechanism is revealed by comparing the results of the fibrous MWCNTs with the spherical CBs.
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- 2019
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18. Caffeine attenuates brain injury but increases mortality induced by high-intensity blast wave exposure
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Dong Liu, Ping Li, Yan Zhao, Zi-Ai Zhao, Yan Peng, Xing Chen, Zheng-Guo Wang, Nan Yang, Hua-Ke Tian, Yuan-Guo Zhou, Ya-Lei Ning, Xiu-Zhu Zhang, and Jiang-Fan Chen
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Male ,0301 basic medicine ,Traumatic brain injury ,Physiology ,Poison control ,Lung injury ,Toxicology ,Neuroprotection ,Blast injury ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Blast Injuries ,Caffeine ,Brain Injuries, Traumatic ,Injury prevention ,medicine ,Animals ,business.industry ,Major trauma ,General Medicine ,medicine.disease ,Mice, Inbred C57BL ,Disease Models, Animal ,Neuroprotective Agents ,030104 developmental biology ,chemistry ,business ,030217 neurology & neurosurgery - Abstract
Caffeine is a substance that is consumed worldwide, and it may exert neuroprotective effects against various cerebral insults, including neurotrauma, which is the most prevalent injury among military personnel. To investigate the effects of caffeine on high-intensity blast wave-induced severe blast injury in mice, three different paradigms of caffeine were applied to male C57BL/6 mice with severe whole body blast injury (WBBI). The results demonstrated that chronic caffeine treatment alleviated blast-induced traumatic brain injury (bTBI); however, both chronic and acute caffeine treatments exacerbated blast-induced lung injuries and, more importantly, increased both the cumulative and time-segmented mortalities postinjury. Interestingly, withdrawing caffeine intake preinjury resulted in favorable outcomes in mortality and lung injury, similar to the findings in water-treated mice, and had the trend to attenuate brain injury. These findings demonstrated that although drinking coffee or caffeine preparations attenuated blast-induced brain trauma, these beverages may place personnel in the battlefield at high risk of casualties, which will help us re-evaluate the therapeutic strategy of caffeine application, particularly in multiple-organ-trauma settings. Furthermore, these findings provided possible strategies for reducing the risk of casualties with caffeine consumption, which may help to change the coffee-drinking habits of military personnel.
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- 2019
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19. Transformation and kinetics of chlorine-containing products during pyrolysis of plastic wastes
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Junfeng Zhang, Ke Tian, Taiping Qing, Hong Jiang, and Jing Pan
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chemistry.chemical_classification ,Thermogravimetric analysis ,Environmental Engineering ,Chemistry ,Health, Toxicology and Mutagenesis ,Kinetics ,Public Health, Environmental and Occupational Health ,chemistry.chemical_element ,General Medicine ,General Chemistry ,Activation energy ,Pollution ,Polyvinyl chloride ,chemistry.chemical_compound ,Hydrocarbon ,Chemical engineering ,Biochar ,Thermogravimetry ,Chlorine ,Environmental Chemistry ,Pyrolysis ,Plastics - Abstract
Pyrolysis can not only effectively dispose of plastic wastes but also reclaim valuable chemicals and biochar. However, the production and release of second pollutants, particularly chlorine-containing products, have been neglected. The mechanism for the transformation of chlorine during the pyrolysis of plastic wastes remains unclear. Herein, a thermogravimetric Fourier transform infrared mass spectrometry technology was used to investigate the migration and transformation of substances during the pyrolysis of polyvinyl chloride (PVC) plastic from 200 °C to 900 °C with heating rates of 5, 50, 100, 150, and 200 K min−1. Results show the first stage of weight loss is at 200 °C-360 °C, where the dehydrochlorination of PVC mainly occurred, accompanied by the formation of conjugated double bonds and a small number of hydrocarbon compounds. The second stage of weight loss is at 360 °C-550 °C, where the breakage and rearrangement of the long polyethene chain may occur. Kinetics analysis shows the higher activation energy value is in the second stage, which indicates that the second stage reaction is less likely to occur and the Flynn–Wall–Ozawa method is more suitable for the study of plastic pyrolysis kinetics. This study suggests that second pollutants can be minimized during controllable pyrolysis.
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- 2021
20. The Spinal α7-Nicotinic Acetylcholine Receptor Contributes to the Maintenance of Cancer-Induced Bone Pain
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Xuebi Tian, Yu-Ke Tian, Feng Gao, Ya-Qun Zhou, Ting Yang, Hui Yang, Anne Manyande, Long-Qing Zhang, Shu-Ping Chen, Chao Chen, Wen Zhang, and Jie Wang
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Agonist ,Allosteric modulator ,clinical_medicine ,medicine.drug_class ,Analgesic ,α7-nAChR ,Pharmacology ,NF-κB ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,030202 anesthesiology ,medicine ,Journal of Pain Research ,Bone pain ,Original Research ,PNU-282,987 ,biology ,business.industry ,Chronic pain ,health ,medicine.disease ,Anesthesiology and Pain Medicine ,chemistry ,cancer-induced bone pain ,nervous system ,biology.protein ,medicine.symptom ,NeuN ,Signal transduction ,business ,030217 neurology & neurosurgery - Abstract
Ting Yang1 1, Yaqun Zhou1 1, Wen Zhang1 1, Longqing Zhang1 1, Shuping Chen1 1, Chao Chen1 1, Feng Gao1 1, Hui Yang1 1, Anne Manyande2 2, Jie Wang3 3, Yuke Tian1 1, Xuebi Tian1 1 1Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 2School of Human and Social Sciences, University of West London, London, UK; 3State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, Hubei, People’s Republic of ChinaCorrespondence: Xuebi TianDepartment of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue 1095#, Wuhan, Hubei, 430030, People’s Republic of ChinaTel +862783663423Fax +862783662853Email Tianxb@hust.edu.cnIntroduction: Cancer-induced bone pain (CIBP) is acknowledged as a multifactorial chronic pain that tortures advanced cancer patients, but existing treatment strategies for CIBP have not been satisfactory yet. Investigators have demonstrated that the activation of α 7-nAChRs exerts analgesic effects in some chronic pain models. However, the role of spinal α 7-nAChRs in CIBP remains unknown. This study was designed to investigate the role of α 7-nAChRs in a well-established CIBP model induced by Walker 256 rat mammary gland carcinoma cells.Methods: The paw withdrawal threshold (PWT) of the ipsilateral hind paw was measured using von Frey filament. The expressions of spinal α 7-nAChRs and NF-κB were measured with Western blotting analysis. Immunofluorescence was employed to detect the expression of α 7-nAChRs and co-expressed of α 7-nAChRs with NeuN or GFAP or Iba1.Results: Experiment results showed that the expression of spinal α 7-nAChRs was significantly downregulated over time in CIBP rats, and in both CIBP rats and sham rats, most of the α 7-nAChRs located in neurons. Behavioral data suggested PNU-282,987, a selective α 7-nAChRs agonist, dose-dependently produced analgesic effect and positive allosteric modulator could intensify its effects. Further, repeated administration of PNU-282,987 reversed the expression of α 7-nAChRs, inhibited the nuclear factor kappa B (NF-κB) signaling pathway, and attenuates CIBP-induced mechanical allodynia state as well.Conclusion: These results suggest that the reduced expression of spinal α 7-nAChRs contributes to the maintenance of CIBP by upregulating NF-κB expression, which implying a novel pharmacological therapeutic target for the treatment of CIBP.Keywords: cancer-induced bone pain, α 7-nAChR, NF-κB, PNU-282,987
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- 2021
21. Sodium Butyrate More Effectively Mitigates the Negative Effects of High-Concentrate Diet in Dairy Cows than Sodium β -Hydroxybutyrate via Reducing Free Bacterial Cell Wall Components in Rumen Fluid and Plasma
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Junhui Liu, Guohao Huang, Tianle He, Guozhong Dong, Ruiming Zhang, Yawang Sun, Ke Tian, Yongjiang Wu, Juncai Chen, and National Natural Science Foundation of China
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sodium β-hydroxybutyrate ,Health, Toxicology and Mutagenesis ,Sodium ,chemistry.chemical_element ,Lipopolysaccharide ,Peptidoglycan ,peptidoglycan ,Toxicology ,Proinflammatory cytokine ,03 medical and health sciences ,Rumen ,chemistry.chemical_compound ,Animal science ,Lactation ,Sodium β-hydroxybutyrate ,medicine ,Sodium β -hydroxybutyrate ,dairy cows ,sodium butyrate ,030304 developmental biology ,0303 health sciences ,lipopolysaccharide ,0402 animal and dairy science ,Acute-phase protein ,Dairy cows ,food and beverages ,Sodium butyrate ,04 agricultural and veterinary sciences ,040201 dairy & animal science ,Lipoteichoic acid ,lipoteichoic acid ,medicine.anatomical_structure ,chemistry ,Medicine ,Somatic cell count - Abstract
This article belongs to the Special Issue Histological Effects of Endotoxins., The present study was aimed at investigating the effects of sodium butyrate and sodium β-hydroxybutyrate on lactation and health of dairy cows fed a high-concentrate (HC) diet. Eighty mid-lactation dairy cows with an average milk yield of 33.75 ± 5.22 kg/d were randomly allocated to four groups (n = 20 per group) and were fed either a low-concentrate (LC) diet, a HC diet, the HC diet with 1% sodium butyrate (HCSB), or the HC diet with 1% sodium β-hydroxybutyrate (HCHB). The feeding trial lasted for 7 weeks, with a 2-week adaptation period and a 5-week measurement period, and the trial started from 96 ± 13 d in milk. Sodium butyrate supplementation delayed the decline in milk production and improved milk synthesis efficiency and milk fat content. Additionally, it decreased the proinflammatory cytokines and acute phase proteins (APPs) in plasma, the leucocytes in blood, the somatic cell count (SCC) in milk, and the gene expression of pattern recognition receptors (PRRs) and proinflammatory cytokines in the mammary gland, due to decreasing the contents of bacterial cell wall components (lipopolysaccharide, LPS; peptidoglycan, PGN; and lipoteichoic acid, LTA) in the rumen and plasma, compared with the HC diet. Sodium β-hydroxybutyrate supplementation also improved milk yield, milk synthesis efficiency and milk fat content and partially reduced the adverse effects caused by the HC diet, but it had no effect on decreasing bacterial cell wall components in the rumen and plasma, compared with the HC diet. Collectively, both sodium butyrate and sodium β-hydroxybutyrate mitigated the negative effects of HC diet on lactation and health of dairy cows, with sodium butyrate being more effective than sodium β-hydroxybutyrate., This work was financially supported by the National Natural Science Foundation of China (Grant number: 31672448).
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- 2021
22. Bone Mesenchymal Stem Cells Contribute to Ligament Regeneration and Graft-Bone Healing after Anterior Cruciate Ligament Reconstruction with Silk-Collagen Scaffold
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Junqi Liu, Ke Tian, Yangdi Chen, Wenhao Hu, and Fanggang Bi
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Anterior cruciate ligament reconstruction ,Article Subject ,medicine.medical_treatment ,Anterior cruciate ligament ,Population ,Bone healing ,behavioral disciplines and activities ,03 medical and health sciences ,0302 clinical medicine ,medicine ,education ,Internal medicine ,Molecular Biology ,Bone mineral ,030222 orthopedics ,education.field_of_study ,Chemistry ,Cell Biology ,RC31-1245 ,030104 developmental biology ,medicine.anatomical_structure ,Ligament ,Bone marrow ,Type I collagen ,Research Article - Abstract
Anterior cruciate ligament (ACL) reconstruction was realized using a combination of bone mesenchymal stem cells (BMSCs) and silk–collagen scaffold, and an in vivo evaluation of this combination was performed. By combining type I collagen and degummed silk fibroin mesh, silk–collagen scaffolds were prepared to simulate ligament components. BMSCs isolated from bone marrow of rabbits were cultured for a homogenous population and seeded on the silk–collagen scaffold. In the scaffold and BMSC (S/C) group, scaffolds were seeded with BMSCs for 72 h and then rolled and used to replace the ACL in 20 rabbits. In the scaffold (S) group, scaffolds immersed only in culture medium for 72 h were used for ACL reconstruction. Specimens were collected at 4 and 16 weeks postoperatively to assess ligament regeneration and bone integration. HE and immunohistochemical staining (IHC) were performed to assess ligament regeneration in the knee cavity. To assess bone integration at the graft–bone interface, HE, Russell–Movat staining, micro-CT, and biomechanical tests were performed. After 4 weeks, vigorous cell proliferation was observed in the core part of the scaffold in the S/C group, and a quantity of fibroblast-like cells and extracellular matrix (ECM) was observed in the center part of the graft at 16 weeks after surgery. At 4 and 16 weeks postoperatively, the tenascin-C expression in the S/C group was considerably higher than that in the S group (4 w, p < 0.01 ; 16 w, p < 0.01 ). Furthermore, bone integration was better in the S/C group than in the S group, with histological observation of trabecular bone growth into the graft and more mineralized tissue formation detected by micro-CT (4 w, bone volume fraction (BV/TV), p = 0.0169 , bone mineral density (BMD), p = 0.0001 ; 16 w, BV/TV, p = 0.1233 , BMD, p = 0.0494 ). These results indicate that BMSCs promote ligament regeneration in the knee cavity and bone integration at the graft–bone interface. Silk–collagen scaffolds and BMSCs will likely be combined for clinical practice in the future.
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- 2020
23. PPARγ activation mitigates mechanical allodynia in paclitaxel-induced neuropathic pain via induction of Nrf2/HO-1 signaling pathway
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Nan Chen, Xiao-Mei Wang, Jia Sun, Yu-Ke Tian, Shu-Ping Chen, Dan-Yang Li, Da-Wei Ye, Dai-Qiang Liu, and Ya-Qun Zhou
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0301 basic medicine ,Agonist ,Male ,Pain Threshold ,Paclitaxel ,PPARγ ,medicine.drug_class ,NF-E2-Related Factor 2 ,Analgesic ,RM1-950 ,Pharmacology ,Neuropathic pain ,Rats, Sprague-Dawley ,Rosiglitazone ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Downregulation and upregulation ,Oltipraz ,Medicine ,Animals ,Receptor ,Analgesics ,business.industry ,Antagonist ,Pain Perception ,General Medicine ,Up-Regulation ,PPAR gamma ,Disease Models, Animal ,030104 developmental biology ,chemistry ,Spinal Cord ,Hyperalgesia ,Oxidative stress ,030220 oncology & carcinogenesis ,Heme Oxygenase (Decyclizing) ,Neuralgia ,Therapeutics. Pharmacology ,business ,medicine.drug ,Signal Transduction - Abstract
Paclitaxel-induced neuropathic pain (PINP) is a dose-limiting side effect and is refractory to widely used analgesic drugs. Previous studies have demonstrated a protective role of peroxisome proliferator-activated receptor gama (PPARγ) in neuropathic pain. However, whether PPARγ activation could alleviate PINP remains to be elucidated. Our previous study has validated the analgesic effect of oltipraz, an nuclear factor erythroid-2 related factor 2 (Nrf2) activator, in a rat model of PINP. In this study, we tested the hypothesis that rosiglitazone, a selective agonist of PPARγ, could attenuate PINP through induction of Nrf2/heme oxygenase-1 (HO-1) signaling pathway. Paclitaxel was injected intraperitoneally on four alternate days to induce neuropathic pain. Paw withdrawal threshold was used to evaluate mechanical allodynia. Western blot and immunofluorescence were used to examine the expression and distribution of PPARγ, Nrf2 and HO-1 in the spinal cord. Our results showed that rosiglitazone attenuated established PINP and delayed the onset of PINP via activation of PPARγ, which were reversed by PPARγ antagonist GW9662. Moreover, rosiglitazone inhibited downregulation of PPARγ in the spinal cord of PINP rats. Furthermore, the analgesic effect of rosiglitazone against PINP was abolished by trigonelline, an Nrf2 inhibitor. Finally, rosiglitazone significantly increased expression of Nrf2 and HO-1 in the spinal cord of PINP rats. Collectively, these results indicated that PPARγ activation might mitigate PINP through activating spinal Nrf2/HO-1 signaling pathway. Our results may provide an alternative option for PINP patients.
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- 2020
24. Theoretical Study on the Mechanism for the Formation of Nitro Compounds in Red Oil
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Meng-Ke Tian, Hong-Bin Tang, Xue-Hai Ju, and Shuang-Ling Tang
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Article Subject ,Cyclohexane ,Red oil ,Chemistry ,Radical ,General Chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Medicinal chemistry ,Transition state ,010406 physical chemistry ,0104 chemical sciences ,Solvent ,chemistry.chemical_compound ,Reaction rate constant ,Nitric acid ,Nitro ,QD1-999 - Abstract
The mechanisms involved in reactions between methane, n-hexane, n-butanol, cyclohexane, and nitric acid were explored by density functional theory calculations. All the calculations in gas phase and n-tributyl phosphate (TBP) solvent were performed at the B3LYP/6–311++G ∗ ∗ and CCSD(T)/6–311++G ∗ ∗ levels of theory. The results showed that TBP has an important effect on the reactions between nitric acid and alkanes or butanol. The reactions were considered as that the radicals (·NO2 and ·NO3 radicals are formed via the HNO3 decomposition under irradiation) initiate the H-atom depletion of the reactants (R), and the produced radicals in red oil combine with ·NO2 radical to form the nitro compounds spontaneously. The rate constants of reactions R + ·NO2 and R + ·NO3 differ substantially, the rate constants of the latter being much larger than those of the former. In the reactions of R + ·NO3, the transition states and products are 20 kJ/mol and 100 kJ/mol or more stable than the reactants, respectively, but the reactions of R + ·NO2 need to overcome energy barriers over 25 kJ/mol. The formations of products mainly depend on the reactions of R + ·NO3. For the same type of alkanes (either chain or cyclic ones), the lower the relative stabilities of carbon-centered radicals are, the more reactive the alkanes are. Cyclohexane is the most competitive species, followed by n-butanol, n-alkanes, and methane which are the least competitive.
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- 2020
25. Carvacrol suppresses inflammatory responses in rheumatoid arthritis fibroblast‐like synoviocytes
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Guanlei Liu, Gu Chenxi, Yu Li, Jianzhong Xu, and Ke Tian
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0301 basic medicine ,Chemistry ,p38 mitogen-activated protein kinases ,Interleukin ,Inflammation ,Cell Biology ,Pharmacology ,Biochemistry ,Proinflammatory cytokine ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,030220 oncology & carcinogenesis ,TLR4 ,medicine ,Tumor necrosis factor alpha ,Carvacrol ,Viability assay ,medicine.symptom ,Molecular Biology - Abstract
Background Fibroblast-like synoviocytes (FLSs) play an essential role in the chronic inflammatory process of rheumatoid arthritis (RA). Carvacrol is a natural monoterpenic phenol that retains significant anti-inflammatory activity. However, the effect of carvacrol on inflammatory response in RA-FLSs has not yet been reported. The present study aimed to investigate the role of carvacrol in lipopolysaccharides (LPS)-induced inflammatory response in human RA-FLSs. Methods Cell viability and proliferation were measured by MTT and Cell Counting Kit-8 assays, respectively. The migration was detected by transwell assay. The production of inflammatory cytokines and matrix metalloproteinases (MMPs) were analyzed by enzyme-linked immunosorbent assay. The expressions of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), NF-κB, p38, p-p38, ERK1/2, p-ERK1/2, c-Jun N-terminal kinase (JNK), and p-JNK were detected by Western blot analysis. Results Carvacrol-inhibited LPS-induced cell proliferation and migration of RA-FLSs. The production of inflammatory cytokines, including tumor necrosis factor alpha, interleukin (IL)- 6, and IL-8, was reduced by carvacrol in LPS-induced RA-FLSs. Meanwhile, the induction of MMPs, including MMP-1, MMP-3, and MMP-13, caused by LPS stimulation was inhibited by carvacrol in RA-FLSs. Furthermore, carvacrol prevented LPS-induced activation of the TLR4/MyD88/NF-κB, p38, and ERK1/2 pathways in RA-FLSs. Conclusions Carvacrol-mitigated LPS-induced cell proliferation, migration, and inflammation in RA-FLSs. The TLR4/MyD88/NF-κB, p38 and ERK1/2 pathways might be involved in the protective effect of carvacrol.
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- 2018
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26. Preparation of Microporous Organic Polymers via UV-Initiated Radical Copolymerization
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Feifei Xie, Ting-Ting Zhu, Zhengchen Wu, Ke Tian, Lei Li, Haoqing Yang, and Ting Huang
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chemistry.chemical_classification ,Polymers and Plastics ,010405 organic chemistry ,Organic Chemistry ,Polymer ,Microporous material ,010402 general chemistry ,Divinylbenzene ,01 natural sciences ,0104 chemical sciences ,MOPS ,Inorganic Chemistry ,chemistry.chemical_compound ,Monomer ,chemistry ,Polymer chemistry ,Materials Chemistry ,Copolymer - Abstract
UV-initiated radical copolymerization has been successfully applied for the preparation of two kinds of microporous organic polymers (MOPs) based on divinylbenzene (DVB)/bismaleimide (BMI) monomers and DVB/pentaerythritol tetraacrylate (PET4A). The obtained MOPs exhibit high BET surface areas and good CO
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- 2018
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27. Reactive oxygen species scavengers ameliorate mechanical allodynia in a rat model of cancer-induced bone pain
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Fei Chen, Wei Mei, Yu-Ke Tian, Hui-Xian Zhang, Xue-Rong Zhou, Ya-Qun Zhou, Jia Sun, Shu-Ping Chen, Dai-Qiang Liu, Heike L. Rittner, and Da-Wei Ye
- Subjects
medicine.medical_treatment ,Clinical Biochemistry ,Intraperitoneal injection ,Pharmacology ,Cancer-induced bone pain ,Biochemistry ,Bone and Bones ,Article ,Cyclic N-Oxides ,Rats, Sprague-Dawley ,03 medical and health sciences ,0302 clinical medicine ,PBN ,medicine ,Animals ,Bone pain ,lcsh:QH301-705.5 ,chemistry.chemical_classification ,Analgesics ,Reactive oxygen species ,lcsh:R5-920 ,Microglia ,Organic Chemistry ,Cancer ,Tempol ,Cancer Pain ,Free Radical Scavengers ,Spinal cord ,medicine.disease ,Rats ,Disease Models, Animal ,medicine.anatomical_structure ,Nociception ,chemistry ,lcsh:Biology (General) ,Hyperalgesia ,030220 oncology & carcinogenesis ,Anesthesia ,Neuropathic pain ,Female ,Spin Labels ,medicine.symptom ,Reactive Oxygen Species ,lcsh:Medicine (General) ,030217 neurology & neurosurgery ,Research Paper - Abstract
Cancer-induced bone pain (CIBP) is a frequent complication in patients suffering from bone metastases. Previous studies have demonstrated a pivotal role of reactive oxygen species (ROS) in inflammatory and neuropathic pain, and ROS scavengers exhibited potent antinociceptive effect. However, the role of spinal ROS remains unclear. In this study, we investigated the analgesic effect of two ROS scavengers in a well-established CIBP model. Our results found that intraperitoneal injection of N-tert-Butyl-α-phenylnitrone (PBN, 50 and 100 mg/kg) and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol, 100 and 200 mg/kg) significantly suppressed the established mechanical allodynia in CIBP rats. Moreover, repeated injection of PBN and Tempol showed cumulative analgesic effect without tolerance. However, early treatment with PBN and Tempol failed to prevent the development of CIBP. Naive rats received repetitive injection of PBN and Tempol showed no significant change regarding the nociceptive responses. Finally, PBN and Tempol treatment notably suppressed the activation of spinal microglia in CIBP rats. In conclusion, ROS scavengers attenuated established CIBP by suppressing the activation of microglia in the spinal cord., Graphical abstract fx1, Highlights • PBN and Tempol could suppress established mechanical allodynia in CIBP rats. • Repeated injection of PBN and Tempol showed cumulative analgesic effect. • PBN and Tempol failed to prevent the development of CIBP. • PBN and Tempol could suppress the microglia activation in CIBP rats.
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- 2018
28. Massive Preparation of Coumarone-indene Resin-based Hyper-crosslinked Polymers for Gas Adsorption
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Zhengchen Wu, Lei Li, Ting-Ting Zhu, Ping Lan, Ke Tian, Feifei Xie, and Wei Hu
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chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,General Chemical Engineering ,Organic Chemistry ,Heteroatom ,02 engineering and technology ,Polymer ,Alkylation ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Solvent ,chemistry.chemical_compound ,Adsorption ,Chemical engineering ,chemistry ,medicine ,Molecule ,Coal tar ,Indene ,0210 nano-technology ,medicine.drug - Abstract
Hyper-crosslinked polymers (HCPs) are promising materials for gas capture and storage because of their low cost and easy preparation. In this work, we report the massive preparation of coumarone-indene resin-based hyper-crosslinked polymers via one-step Friedel-Crafts alkylation. Low-cost coumarone-indene resin serves as the new building block and chloroform is employed as both solvent and external crosslinker. A maximum surface area of 966 m2·g−1 is achieved, which is comparable with that of previously-reported coal tar-based porous organic polymers. Most importantly, a large number of heteroatoms including inherent oxygen atoms and introduced chlorine atoms in obtianed HCPs further enhance the interaction between specific sorbate molecule and adsorbent. Therefore, optimal structural and chemical property endow the new coumarone-indene resin-based HCPs with decent gas storage capacity (14.60 wt% at 273 K and 0.1 MPa for CO2; 1.18 wt% at 77.3 K and 0.1 MPa for H2). These results demonstrate that new HCPs are potential candidates for applications in CO2 and H2 capture.
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- 2018
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29. Hierarchically porous carbons with controlled structures for efficient microwave absorption
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Ping Lan, Zhengchen Wu, Ke Tian, Wei Hu, Feifie Xie, Ting Huang, and Lei Li
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Materials science ,Carbonization ,Reflection loss ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Divinylbenzene ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Adsorption ,Chemical engineering ,chemistry ,Polymerization ,Emulsion ,Materials Chemistry ,0210 nano-technology ,Porosity ,Microwave - Abstract
To probe the influence of the porous morphology of carbon materials on their microwave absorption performance, hierarchically porous carbons (HPCs) with designed structures have been successfully prepared starting from poly(divinylbenzene) by emulsion template polymerization. There exist two levels of pores in the obtained HPCs. One level of micro-scale pores templates from the water drops, and the other level of nano-scale pores is created during KOH activation in the subsequent carbonization process. By adjusting the water volume fraction during polymerization and the KOH dosage, both micro- and nano-scale porous structures can be accurately tuned. The influences of pores with diverse scales on microwave adsorption capacity are investigated in detail. Eventually, the maximum reflection loss of −56.4 dB and an effective adsorption bandwidth of 6.0 GHz are achieved. The superior microwave absorption performance of HPCs is attributed to the superimposed contributions of the two-level pores to the enhancement of polarization abilities and the multiple reflections of the microwave.
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- 2018
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30. A novel method to incorporate functional filler into TPSiV for balanced physical properties
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Hua Deng, Qiang Fu, Guojie Zhao, Qinjun Pan, Qin Zhang, and Ke Tian
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chemistry.chemical_classification ,Materials science ,Thermoplastic ,Composite number ,General Engineering ,Percolation threshold ,Polymer ,engineering.material ,chemistry ,Phase (matter) ,Filler (materials) ,Ultimate tensile strength ,Ceramics and Composites ,engineering ,Adhesive ,Composite material - Abstract
Various literatures have reported that incorporating functional fillers into thermoplastic vulcanizates (TPVs) is an ideal method to prepare functional TPVs with balanced properties. Nevertheless, it is quite difficult to achieve that for thermoplastic silicone vulcanizate (TPSiV) due to their rather high silicon rubber (SiR) content as well as delicate balance between processing ability and various physical properties. Herein, a novel method involves using CNT/TPU phase as polymer matrix to disperse TPSiV particles through solution processing is proposed. Compared with randomly dispersed CNTs and traditional segregated CNTs network with TPSiV particles, composites fabricated by such method illustrate much better balance between various properties, including: low percolation threshold (Pc), comprehensive mechanical performance, better electromagnetic interference (EMI) shielding ability, etc. CNT/TPU anchored TPSiV double-percolated composite illustrates comparable Pc (0.42 wt%) to traditional segregated TPSiV/CNT composite (0.38 wt%), while the TPSiV composite with randomly dispersed CNT shows apparently high Pc (1.37 wt%). More importantly, both tensile strength and elongation at break are improved for these compoistes with double-percolation structure. It is even better than neat TPSiV composites at the same CNT loading. The prepared two types of segregated composites demonstrate similar electrical conductivity at high filler loading (≥1 wt%), enabling them with similar EMI performance, but the one with CNT/TPU as adhesive phase is much more stable after 100 times bending, illustrating negligible attenuation. This study provides a novel approach for incorporating functional fillers into TPSiV matrix for balanced properties.
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- 2021
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31. Hierarchically Porous Carbon Derived from PolyHIPE for Supercapacitor and Deionization Applications
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Likun Pan, Feifei Xie, Lei Li, Yuquan Li, Miao Wang, Zhengchen Wu, Ke Tian, and Wei Hu
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Supercapacitor ,Materials science ,Capacitive deionization ,Carbonation ,02 engineering and technology ,Surfaces and Interfaces ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Divinylbenzene ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Specific surface area ,Emulsion ,Electrochemistry ,General Materials Science ,0210 nano-technology ,Porosity ,Mesoporous material ,Spectroscopy - Abstract
Hierarchically porous carbon (HPC) materials with interconnected pore texture are produced from porous poly(divinylbenzene) precursor, synthesized by polymerizing high internal phase emulsion. After carbonation, the macroporous structures of the poly(divinylbenzene) precursor are preserved and enormous micro/mesopores via carbonation with KOH are produced, resulting in interconnected hierarchical pore network. The prepared HPC has a maximum specific surface area of 2189 m2 g-1. The electrode materials for supercapacitor and capacitive deionization (CDI) device employing the formed HPC exhibit high specific capacity of 88 mAh g-1 through a voltage range of 1V (319 F g-1 at 1 A g-1) and superior electrosorption capacity of 21.3 mg g-1 in 500 mg L-1 NaCl solution, respectively. The excellent capacitive performance could be ascribed to the combination of high specific surface area and favorable hierarchical porous structure.
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- 2017
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32. Nitrogen-Doped Porous Carbons Derived from Triarylisocyanurate-Cored Polymers with High CO2 Adsorption Properties
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Wei Hu, Feifei Xie, Lei Li, Zhengchen Wu, and Ke Tian
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chemistry.chemical_classification ,Materials science ,Carbonization ,General Chemical Engineering ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,Microporous material ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Nitrogen ,0104 chemical sciences ,Fuel Technology ,Porous carbon ,Chemical engineering ,chemistry ,Specific surface area ,Organic chemistry ,0210 nano-technology ,Carbon ,Bar (unit) - Abstract
A series of N-doped porous carbon materials have been successfully prepared by using nitrogen-rich triarylisocyanurate-cored polymers as carbon precursor. The cross-linked networks explain the precursor with high carbonaceous residues in the following carbonization. The influence of KOH dosage and activation temperature on the specific surface area and nitrogen content of the resultant carbon materials is investigated in detail. Eventually, a maximum specific surface area of 2341 m2 g–1 and nitrogen content of 1.7 wt % are achieved in the resultant carbon materials. High CO2 capacity (30.2 wt % at 273 K/1 bar and 17.2 wt % at 298 K/1 bar) is attributed to abundant microporous structures and basic sites, superior to that of the most porous carbon materials reported in the previous literature. In addition, the carbon materials also demonstrate high H2 and CH4 uptake (2.7 wt % at 77.3 K/1.13 bar and 3.8 wt % at 273 K/1.13 bar, respectively). The characters of easy preparation and high gas uptake capacity end...
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- 2017
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33. Down-regulation of NOX4 by betulinic acid protects against cerebral ischemia-reperfusion in mice
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Hui-ge Li, Yu-Ke Tian, Xiao-min Zhang, Chen-chen Zhang, Ailin Luo, Hui Xu, and Pei Lu
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0301 basic medicine ,Ischemia ,Down-Regulation ,Pharmacology ,medicine.disease_cause ,Biochemistry ,Brain Ischemia ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Betulinic acid ,Genetics ,Animals ,Medicine ,cardiovascular diseases ,Betulinic Acid ,Stroke ,chemistry.chemical_classification ,Reactive oxygen species ,NADPH oxidase ,biology ,business.industry ,NOX4 ,medicine.disease ,Triterpenes ,Disease Models, Animal ,Treatment Outcome ,030104 developmental biology ,chemistry ,NADPH Oxidase 4 ,Reperfusion Injury ,biology.protein ,Pentacyclic Triterpenes ,Reactive Oxygen Species ,business ,Reperfusion injury ,030217 neurology & neurosurgery ,Oxidative stress - Abstract
Ischemic stroke leads to high potentiality of mortality and disability. The current treatment for ischemic stroke is mainly focused on intravenous thrombolytic therapy. However, ischemia/ reperfusion induces neuronal damage, which significantly influences the outcome of patients with ischemic stroke, and the exact mechanism implicated in ischemia/reperfusion injury remains unclear, although evidence shows that oxidative stress is likely to be involved. Betulinic acid is mainly known for its anti-tumor and anti-inflammatory activities. Our previous study showed that betulinic acid could decrease the reactive oxygen species (ROS) production by regulating the expression of NADPH oxidase. Thus, we hypothesized that betulinic acid may protect against brain ischemic injury in the animal model of stroke. Focal cerebral ischemia was achieved by using the standard intraluminal occlusion method and reperfusion enabled after 2 h ischemia. Neurological deficits were scored. Infarct size was determined with 2,3,5-triphenyltetrazolium chloride monohydrate (TTC) staining and the mRNA expression of NADPH oxidase 4 (NOX4) was determined by RT-PCR in infarct tissue. ROS generation and apoptosis in ischemic tissue were analyzed by measuring the oxidative conversion of cell permeable 2',7'-dichloro-fluorescein diacetate (DCF-DA) to fluorescent dichlorofluorescein (DCF) in fluorescence microplate reader and TUNEL assay, respectively. In Kunming mice, 2 h of middle cerebral artery (MCA) occlusion followed by 24 or 72 h of reperfusion led to an enhanced NOX4 expression in the ischemic hemisphere. This was associated with elevated levels of ROS generation and neuronal apoptosis. Pre-treatment with betulinic acid (50 mg/kg/day for 7 days via gavage) prior to MCA occlusion prevented the ischemia/reperfusion-induced up-regulation of NOX4 and ROS production. In addition, treatment with betulinic acid could markedly blunt the ischemia/reperfusion-induced neuronal apoptosis. Finally, betulinic acid reduced infarct volume and ameliorated the neurological deficit in this stroke mouse model. Our results suggest that betulinic acid protects against cerebral ischemia/reperfusion injury in mice and the down-regulation of NOX4 may represent a mechanism contributing to this effect.
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- 2017
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34. Room-Temperature Phosphorescence Detection of Silver Ions Based on Glutathione Capped Mn-Doped ZnS Quantum Dots
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Pan Deng, Yan-Hong Ma, Lian-Lian Wang, Fan Peng, Xi-Ke Tian, and Li-Qiang Lu
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Materials science ,Biomedical Engineering ,Bioengineering ,02 engineering and technology ,General Chemistry ,Glutathione ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,Ion ,chemistry.chemical_compound ,chemistry ,Quantum dot ,General Materials Science ,Mn doped ,0210 nano-technology ,Phosphorescence - Published
- 2017
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35. The Role of Spinal GABAB Receptors in Cancer-Induced Bone Pain in Rats
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Zhen-peng Song, Yu-Ke Tian, Dai-Qiang Liu, Heike L. Rittner, Shu-Ping Chen, Shaobing Yang, Ya-Qun Zhou, Qiao-Chu Fu, Da-Wei Ye, Bingrui Xiong, Wen Zhang, and Anne Manyande
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Pain Threshold ,0301 basic medicine ,Agonist ,Baclofen ,medicine.medical_specialty ,Time Factors ,clinical_medicine ,medicine.drug_class ,Bone Neoplasms ,Pharmacology ,GABAB receptor ,Rats, Sprague-Dawley ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Glial Fibrillary Acidic Protein ,Animals ,Medicine ,Cyclic adenosine monophosphate ,Protein kinase A ,Pain Measurement ,business.industry ,Carcinoma ,Cancer Pain ,CREB-Binding Protein ,Cyclic AMP-Dependent Protein Kinases ,Rats ,Gene Expression Regulation, Neoplastic ,Disease Models, Animal ,030104 developmental biology ,Anesthesiology and Pain Medicine ,Nociception ,Endocrinology ,Receptors, GABA-B ,Spinal Cord ,Neurology ,chemistry ,GABA-B Receptor Agonists ,Phosphopyruvate Hydratase ,Neuropathic pain ,Female ,Neurology (clinical) ,Signal transduction ,business ,030217 neurology & neurosurgery - Abstract
Cancer-induced bone pain (CIBP) remains a major challenge in advanced cancer patients because of our lack of understanding of its mechanisms. Previous studies have shown the vital role of γ-aminobutyric acid B receptors (GABABRs) in regulating nociception and various neuropathic pain models have shown diminished activity of GABABRs. However, the role of spinal GABABRs in CIBP remains largely unknown. In this study, we investigated the specific cellular mechanisms of GABABRs in the development and maintenance of CIBP in rats. Our behavioral results show that acute as well as chronic intrathecal treatment with baclofen, a GABABR agonist, significantly attenuated CIBP-induced mechanical allodynia and ambulatory pain. The expression levels of GABABRs were significantly decreased in a time-dependent manner and colocalized mostly with neurons and a minority with astrocytes and microglia. Chronic treatment with baclofen restored the expression of GABABRs and markedly inhibited the activation of cyclic adenosine monophosphate (cAMP)-dependent protein kinase and the cAMP-response element-binding protein signaling pathway. Perspective Our findings provide, to our knowledge, the first evidence that downregulation of GABABRs contribute to the development and maintenance of CIBP and restored diminished GABABRs attenuate CIBP-induced pain behaviors at least partially by inhibiting the protein kinase/cAMP-response element-binding protein signaling pathway. Therefore, spinal GABABR may become a potential therapeutic target for the management of CIBP.
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- 2017
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36. Facile Preparation of Core–Shell Fe3O4@Polypyrrole Composites with Superior Electromagnetic Wave Absorption Properties
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Wei Hu, Donggui Tan, Jingjing Wang, Zhengchen Wu, Ke Tian, Mengxing Su, and Lei Li
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Conductive polymer ,Materials science ,Reflection loss ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Polypyrrole ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,General Energy ,chemistry ,Polymerization ,Etching (microfabrication) ,Transmission electron microscopy ,Physical and Theoretical Chemistry ,Composite material ,0210 nano-technology ,Absorption (electromagnetic radiation) ,Layer (electronics) - Abstract
Core–shell Fe3O4@polypyrrole (PPy) composites with excellent electromagnetic wave absorption properties have been prepared by a sequential process of etching, polymerization, and replication. Templating from pre-prepared Fe3O4 microspheres, ferric ions were released from the skin layer of the microspheres by acid etching and initiated the oxidative polymerization of pyrrole in suit. The morphological and textural evolution of core–shell Fe3O4@PPy composites depending on etching time was investigated by scanning and transmission electron microscope. A maximum reflection loss of as much as −41.9 dB (>99.99% absorption) at 13.3 GHz with a matching layer thickness of 2.0 mm was achieved when the etching time was 5 min. In comparison with other conductive polymer-based core–shell composites reported previously, the Fe3O4@PPy composites in this study not only possess better reflection loss performance but also demonstrate a wider effective absorption bandwidth (
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- 2017
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37. Preparation of N-Doped Supercapacitor Materials by Integrated Salt Templating and Silicon Hard Templating by Pyrolysis of Biomass Wastes
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Hong Jiang, Bin-Hai Cheng, Shun Zhang, and Ke Tian
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Supercapacitor ,Materials science ,Silicon ,Renewable Energy, Sustainability and the Environment ,General Chemical Engineering ,technology, industry, and agriculture ,chemistry.chemical_element ,Lignocellulosic biomass ,02 engineering and technology ,General Chemistry ,Chemical vapor deposition ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Environmental Chemistry ,Gravimetric analysis ,0210 nano-technology ,Melamine ,Pyrolysis ,Carbon - Abstract
For safe disposal and environmentally benign recycling, lignocellulosic biomass wastes are increasingly studied for use as precursors for the preparation of value-added porous carbon materials. However, conventional chemical vapor deposition is time consuming and difficult to perform on a large scale. Herein, we obtained nitrogen-doped porous carbon materials (NPCMs) with high supercapacitor performance by one-pot copyrolysis of a carbon precursor (wheat straw), nitrogen precursor (melamine), and salt templating (mixed salt of KCl/ZnCl2 at 51:49). The NPCM with 7.78% nitrogen content exhibited an excellent gravimetric capacitance of 223.9 F g–1, which is mainly attributed to the increase in surface area by the activation of salt templating and the decrease in ion-transport resistance by N doping of the NPCM. The removal of silicon in pyrolysis products efficiently enhanced the capacitance of materials, but there was a negative effect on capacitance if the silicon was removed from feedstocks before pyrolys...
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- 2017
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38. Sevoflurane-induced isoelectric EEG and burst suppression: differential and antagonistic effect of added nitrous oxide
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Yu-Ke Tian, B. Y. Zhou, Jia Li, F. Cao, B. Niu, Wei Mei, Y. Fang, and J. Y. Xiao
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Male ,Methyl Ethers ,medicine.medical_treatment ,chemistry.chemical_element ,Blood Pressure ,Electroencephalography ,Oxygen ,Sevoflurane ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Double-Blind Method ,Heart Rate ,030202 anesthesiology ,medicine ,Humans ,Drug Interactions ,Prospective Studies ,ED50 ,Aged ,Anesthetics ,anaesthesia mechanisms ,Dose-Response Relationship, Drug ,nitrous oxide ,medicine.diagnostic_test ,business.industry ,Tracheal intubation ,depth of anaesthesia ,Original Articles ,Nitrous oxide ,Middle Aged ,Burst suppression ,Anesthesiology and Pain Medicine ,Isoelectric point ,chemistry ,Anesthesia ,Anesthetics, Inhalation ,Female ,Original Article ,Anesthesia, Inhalation ,business ,Algorithms ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Summary The objective of this study was to investigate whether nitrous oxide influenced the ED50 of sevoflurane for induction of isoelectric electroencephalogram (ED50isoelectric) differently from its influence on the ED50 of sevoflurane for electroencephalogram burst suppression (ED50burst). In a prospective, randomised, double‐blind, parallel group, up–down sequential allocation study, 77 ASA physical status 1 and 2 patients received sevoflurane induction and, after tracheal intubation, were randomly allocated to receive sevoflurane with either 40% oxygen in air (control group) or 60% nitrous oxide in oxygen mixture (nitrous group). The ED50isoelectric in the two groups was determined using Dixon's up and down method, starting at 2.5% with 0.2% step size of end‐tidal sevoflurane. The electroencephalogram was considered as isoelectric when a burst suppression ratio of 100% lasted > 1 min. The subsequent concentrations of sevoflurane administered were determined by the presence or absence of isoelectric electroencephalogram in the previous patient in the same group. The ED50isoelectric in the nitrous group 4.08 (95%CI, 3.95–4.38)% was significantly higher than that in the control group 3.68 (95%CI, 3.50–3.78)% (p < 0.0001). The values for ED50burst were 3.05 (95%CI, 2.66–3.90)% and 3.02 (95%CI, 3.00–3.05)% in nitrous group and control group, respectively (p = 0.52). The addition of 60% nitrous oxide increases ED50isoelectric, but not the ED50burst of sevoflurane. Neither result indicates an additive effect of anaesthetic agents, as might be expected, and possible reasons for this are discussed.
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- 2017
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39. Synthesis of microporous organic polymers via radical polymerization of fumaronitrile with divinylbenzene
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Lei Ding, Feifei Xie, Lei Li, Wei Hu, Zhengchen Wu, and Ke Tian
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chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Organic Chemistry ,Radical polymerization ,Bioengineering ,02 engineering and technology ,Polymer ,Microporous material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Divinylbenzene ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,MOPS ,chemistry.chemical_compound ,Adsorption ,chemistry ,Specific surface area ,Polymer chemistry ,Copolymer ,0210 nano-technology - Abstract
To circumvent the intractable disadvantages of a hyper-cross-linked strategy based on the Friedel–Crafts reaction, a new type of microporous organic polymer (MOP) has been successfully prepared using fumaronitrile and divinylbenzene via alternating radical polymerization. The obtained MOPs exhibit a maximum surface area of 805 m2 g−1 and excellent thermochemical stability. By pyrolyzing the copolymer precursor, a rich nitrogen-doped porous carbon material can be produced, which possesses a specific surface area of 1450 m2 g−1 with a CO2 uptake of 30 wt% at 273 K. The porous carbon also shows a high specific capacitance of 330 F g−1 at a current density of 1.0 A g−1 and a good cycling stability of 96.8% retention after 8000 cycles in a three electrode system. The unique synthesis strategy inspires researchers to seek novel building blocks for the scaled-up preparation of MOPs and the resulting porous carbon has promising application for gas adsorption and energy storage.
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- 2017
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40. One-step preparation of hierarchically porous polyureas: Simultaneous foaming and hyper-crosslinking
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Lei Li, Ke Tian, Jianhui Yu, Hua Bai, Wenqing Li, Hui Gao, and Aijuan Zhang
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Supercapacitor ,Chemical substance ,Materials science ,Polymers and Plastics ,Organic Chemistry ,chemistry.chemical_element ,One-Step ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Monomer ,chemistry ,Polymerization ,Materials Chemistry ,Composite material ,0210 nano-technology ,Mesoporous material ,Porosity ,Carbon - Abstract
A series of hierarchically structured porous polyureas are prepared through the polymerization of diisocyanate monomers and H2O via a one-step and template-free strategy. This simple archetypal reaction combines carbon dioxide foaming process and hyper-crosslinking reaction. The obtained hierarchically porous polyureas (HPUs) consist of micro- and mesopores created by hyper-crosslinking reaction, and macropores generated by carbon dioxide foaming process. The HPUs have a high surface area up to 483.3 m2/g, and large pore volume (0.76 cm3/g). Besides, the nitrogen-doped carbon materials prepared by pyrolyzing the HPUs show a high specific capacitance (209 F/g at 1.0 A/g) and good cycling stability (99.8% capacitance retention after 5000 cycles), demonstrating the advantages of the hierarchically porous structure and nitrogen-rich chemical composition of HPUs.
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- 2017
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41. Berberine protects against ischemia-reperfusion injury: A review of evidence from animal models and clinical studies
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Jia Sun, Ya-Qun Zhou, Xiao-Mei Wang, Shu-Ping Chen, Nan Chen, Dai-Qiang Liu, Yu-Ke Tian, and Da-Wei Ye
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0301 basic medicine ,Berberine ,Ischemia ,Apoptosis ,Pharmacology ,medicine.disease_cause ,Protective Agents ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Immune system ,medicine ,Autophagy ,Animals ,Humans ,Kidney ,business.industry ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,030220 oncology & carcinogenesis ,Reperfusion Injury ,Models, Animal ,business ,Reperfusion injury ,Oxidative stress ,Signal Transduction - Abstract
Ischemia-reperfusion (I/R) injury is accompanied with high morbidity and mortality and has seriously negative social and economic influences. Unfortunately, few effective therapeutic strategies are available to improve its outcome. Berberine is a natural medicine possessing multiple beneficial biological activities. Emerging evidence indicates that berberine has potential protective effects against I/R injury in brain, heart, kidney, liver, intestine and testis. However, up-to-date review focusing on the beneficial role of berberine against I/R injury is not yet available. In this paper, results from animal models and clinical studies are concisely presented and its mechanisms are discussed. We found that berberine ameliorates I/R injury in animal models via its anti-oxidant, anti-apoptotic and anti-inflammatory effects. Moreover, berberine also attenuates I/R injury by suppressing endoplasmic reticulum stress and promoting autophagy. Additionally, regulation of periphery immune system may also contributes to the beneficial effect of berberine against I/R injury. Although clinical evidence is limited, the current studies indicate that berberine may attenuate I/R injury via inhibiting excessive inflammatory response in patients. Collectively, berberine might be used as an alternative therapeutic strategy for the management of I/R injury.
- Published
- 2019
42. The general odorant receptor GmolOR9 from Grapholita molesta (Lepidoptera: Tortricidae) is mainly tuned to eight host-plant volatiles
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Jun-Xiang Wu, Ke-Hang He, Wei Liu, Li-Hui Chen, Xiang-Li Xu, Guirong Wang, and Ke Tian
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Tortricidae ,Arthropod Antennae ,Male ,Moths ,Receptors, Odorant ,General Biochemistry, Genetics and Molecular Biology ,Lepidoptera genitalia ,chemistry.chemical_compound ,Linalool ,Animals ,Amino Acid Sequence ,Herbivory ,Ecology, Evolution, Behavior and Systematics ,Phylogeny ,chemistry.chemical_classification ,Larva ,Volatile Organic Compounds ,biology ,Age Factors ,Pupa ,Ethyl hexanoate ,biology.organism_classification ,Grapholita molesta ,chemistry ,Biochemistry ,Insect Science ,Fruit ,Odorants ,Propionate ,Insect Proteins ,Female ,Heterologous expression ,Agronomy and Crop Science ,Sequence Alignment - Abstract
Grapholita molesta is one of the most destructive fruit pests distributed worldwide. Odorant receptors (ORs) located on the dendritic membrane of chemosensory neurons are deemed to be key molecules for sensing exogenous chemical signals. In this study, GmolOR9, a general OR from G. molesta, was functionally characterized. Quantitative real-time polymerase chain reaction revealed that GmolOR9 was more highly expressed in adults than in other stages, including eggs, larvae, and pupae. GmolOR9 expression was highly significantly more in the antennae of females than in those of males, and the highest level occurred in the antennae of 3-day-old female adults. GmolOR9 was broadly tuned to eight of 47 odorant components tested, including (Z)-3-hexenyl acetate, butyl propionate, ethyl hexanoate, ethyl heptanoate, 1-hexanol, (Z)-3-hexenol, 2-ethyl-1-hexanol, and linalool, by in vitro heterologous expression. Furthermore, electroantennogram responses indicated that the effects of dsOR9-injected females to (Z)-3-hexenyl acetate dramatically decreased. These results suggested that GmolOR9 might be involved in detecting host-plant volatiles. Moreover, (Z)-3-hexenyl acetate might serve as a potential attractant for the biological control of G. molesta.
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- 2019
43. Strain independent twist sensor based on uneven platinum coated hollow core fiber structure
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Yuliya Semenova, Arun Kumar Mallik, Dejun Liu, Qiang Wu, Rahul Kumar, Pengfei Wang, Gerald Farrell, Wei Han, Fengzi Ling, Ke Tian, Fangfang Wei, and Shen Changyu
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Optical fiber ,Materials science ,H600 ,chemistry.chemical_element ,02 engineering and technology ,engineering.material ,01 natural sciences ,law.invention ,010309 optics ,Optics ,Coating ,law ,0103 physical sciences ,Fiber ,Composite material ,Total internal reflection ,business.industry ,Single-mode optical fiber ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,chemistry ,engineering ,0210 nano-technology ,business ,Platinum ,Intensity modulation ,Photonic-crystal fiber - Abstract
Optical fiber based twist sensors usually suffer from high cross sensitivity to strain. Here we report a strain independent twist sensor based on an uneven platinum coated hollow core fiber (HCF) structure. The sensor is fabricated by splicing a section of ~4.5-mm long HCF between two standard single mode fibers, followed by a sputter-coating of a very thin layer of platinum on both sides of the HCF surface. Experimental results demonstrate that twist angles can be measured by monitoring the strength change of transmission spectral dip. The sensor’s cross sensitivity to strain is investigated before and after coating with platinum. It is found that by coating a platinum layer of ~9 nm on the HCF surface, the sensor’s cross sensitivity to strain is significantly decreased with over two orders of magnitude less than that of the uncoated sensor sample. The lowest strain sensitivity of ~2.32×10−5 dB/𝜇𝛆 has been experimentally achieved, which is to the best of our knowledge, the lowest cross sensitivity to strain reported to date for optical fiber sensors based on intensity modulation. In addition, the proposed sensor is capable of simultaneous measurement of strain and twist angle by monitoring the wavelength shift and dip strength variation of a single spectral dip. In the experiment, strain and twist angle sensitivities of 0.61 pm/𝜇𝛆 and 0.10 dB/° have been achieved. Moreover, the proposed sensor offers advantages of ease of fabrication, miniature size, and a good repeatability of measurement.
- Published
- 2019
44. Slit2/Robo1 Mediation of Synaptic Plasticity Contributes to Bone Cancer Pain
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Wensheng He, Feng Gao, Dai Shi, Xuebi Tian, Changbin Ke, Caijuan Li, and Yu-Ke Tian
- Subjects
0301 basic medicine ,RHOA ,Neurite ,Neuroscience (miscellaneous) ,Synaptogenesis ,Bone Neoplasms ,Nerve Tissue Proteins ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Postsynaptic potential ,medicine ,Animals ,Rats, Wistar ,Receptors, Immunologic ,Axon ,Cells, Cultured ,Gene knockdown ,Neuronal Plasticity ,biology ,Chemistry ,Cancer Pain ,Rats ,030104 developmental biology ,medicine.anatomical_structure ,Neurology ,Gene Knockdown Techniques ,Synaptic plasticity ,Excitatory postsynaptic potential ,biology.protein ,Intercellular Signaling Peptides and Proteins ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Synaptic plasticity is fundamental to spinal sensitivity of bone cancer pain. Here, we have shown that excitatory synaptogenesis contributes to bone cancer pain. New synapse formation requires neurite outgrowth and an interaction between axons and dendrites, accompanied by the appositional organization of presynaptic and postsynaptic specializations. We have shown that Slit2, Robo1, and RhoA act as such cues that promote neurite outgrowth and guide the axon for synapse formation. Sarcoma inoculation induces excitatory synaptogenesis and bone cancer pain which are reversed by Slit2 knockdown but aggravated by Robo1 knockdown. Synaptogenesis of cultured neurons are inhibited by Slit2 knockdown but enhanced by Robo1 knockdown. Sarcoma implantation induces an increase in Slit2 and decreases Robo1 and RhoA, while Slit2 knockdown results in an increase of Robo1 and RhoA. These results have demonstrated a molecular mechanism of synaptogenesis in bone cancer pain.
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- 2016
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45. One-pot synthesis of a carbon supported bimetallic Cu–Ag NPs catalyst for robust catalytic hydroxylation of benzene to phenol by fast pyrolysis of biomass waste
- Author
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Ke Tian, Wu-Jun Liu, Shun Zhang, and Hong Jiang
- Subjects
One-pot synthesis ,Inorganic chemistry ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Pollution ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,chemistry ,Yield (chemistry) ,Environmental Chemistry ,Phenol ,0210 nano-technology ,Benzene ,Selectivity ,Pyrolysis ,Bimetallic strip ,Nuclear chemistry - Abstract
The production of phenol in high yield and selectivity by direct catalytic hydroxylation of benzene (HOB) is challenging. In this study, a carbon supported bimetallic Cu–Ag NPs composite was synthesized (Cu–Ag/C) via one-pot fast pyrolysis of Cu–Ag preloaded sawdust. Characterization of the product using various techniques illustrated that Cu and Ag NPs were monodispersed on the biochar, which were obtained during the fast pyrolysis of biomass. The as-synthesized Cu–Ag/C efficiently catalyzed the HOB reaction, resulting in the production of phenol. The maximum yield of phenol was 34.9%, whereas the selectivity for phenol was 96% at 50 °C. The experimental results using various solvents at different retention times incorporated with GC/MS, ESR, and H2-TPD determinations suggested that ˙OH radicals played a dominant role in the catalytic HOB reaction, where Cu and Ag offered a synergistic interaction. This study may provide a new avenue for the preparation of catalysts and offer insight into the synergistic interaction of bimetallic catalytic HOB reactions.
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- 2016
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46. A novel TiC-TiN based spectrally selective absorbing coating: Structure, optical properties and thermal stability
- Author
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Shuai-Sheng Zhao, Dong-Mei Yu, Guang-Ke Tian, Xiang-Hu Gao, and Xiao-Li Qiu
- Subjects
Materials science ,Energy conversion efficiency ,chemistry.chemical_element ,02 engineering and technology ,engineering.material ,Sputter deposition ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Microstructure ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,010309 optics ,Coating ,Chemical engineering ,X-ray photoelectron spectroscopy ,chemistry ,0103 physical sciences ,Absorptance ,engineering ,Thermal stability ,0210 nano-technology ,Tin - Abstract
A novel TiC-TiN/Al2O3 tandem solar selective absorbing coating was successfully deposited on Si (1 0 0) and stainless steel (SS) substrates by reactive RF magnetron sputtering deposition. The spectral characteristics, microstructure, thermal stability and solar-thermal conversion efficiency of the coating before and after a long annealing in vacuum were investigated systematically. The optical constants of the coating are measured by an Ultraviolet–visible-near-infrared (UV/Vis/NIR) spectrometer, and the chemical composition analysis, structure information and surface morphology are investigated using XRD, XPS and FESEM. An excellent absorptance (α = 0.92) and a low emittance (e = 0.11) at 82 °C are obtained by the as-prepared coatings. After annealed at 500 °C for 100 h in vacuum, there is no significant change in micromorphology and optical properties of the coating, which produces a good solar-thermal conversion efficiency. These results indicate that it can be applied as a potential coating material to a high temperature concentrated solar power (CSP) system.
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- 2020
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47. Shear induced formation and destruction behavior of conductive networks in nickel/polyurethane composites during strain sensing
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Hua Deng, Qiang Fu, Qinjun Pan, and Ke Tian
- Subjects
Materials science ,Fabrication ,Scanning electron microscope ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Elastomer ,01 natural sciences ,0104 chemical sciences ,Nickel ,Thermoplastic polyurethane ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,Electrical resistivity and conductivity ,Ceramics and Composites ,Composite material ,0210 nano-technology ,Electrical conductor ,Polyurethane - Abstract
Stretchable sensors based on conductive polymer composites (CPCs) are attracting considerable interest from both academia and industry. For CPCs consist of elastomeric substrates with dispersed conductive fillers, a strain-induced conductivity-drop phenomenon (negative piezo-conductivity effect) is often observed in previous reported studies. Herein, CPCs with unconventional positive piezo-conductivity effect were prepared by employing a facile and low-cost fabrication process based on thermoplastic polyurethane (TPU) and conductive metal particles (nickel/iron particles). For the first time, a strongly stretch-induced conductive networks formation phenomenon was observed under tensile strain, contributing to the electrical resistivity of the composites decreases by more than 6 orders of magnitude under 20% tensile strain. The evolution of conductive networks and resistivity under uniaxial strain were studied with scanning electron microscope (SEM) and a modified mathematic model, respectively. Furthermore, these CPCs exhibits temperature sensing capability between 30 and 60 °C, indicating such method could be used to fabricate multi-functional sensors.
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- 2020
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48. Corrigendum to 'Reactive oxygen species scavengers ameliorate mechanical allodynia in a rat model of cancer-induced bone pain' [REDOX 14 (2017) 391–397]
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Jia Sun, Shu-Ping Chen, Heike L. Rittner, Yu-Ke Tian, Ya-Qun Zhou, Fei Chen, Xue-Rong Zhou, Dai-Qiang Liu, Wei Mei, Da-Wei Ye, and Hui-Xian Zhang
- Subjects
chemistry.chemical_classification ,Reactive oxygen species ,Organic Chemistry ,Clinical Biochemistry ,Rat model ,Cancer ,Pharmacology ,medicine.disease ,Biochemistry ,Redox ,Mechanical Allodynia ,chemistry ,medicine ,medicine.symptom ,Bone pain - Published
- 2020
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49. Effects of chlortetracycline on biological nutrient removal from wastewater
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Hongbo Chen, Xiayi Hu, Junfeng Zhang, Yefeng Zhou, and Ke Tian
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Chlortetracycline ,Environmental Engineering ,Denitrification ,010504 meteorology & atmospheric sciences ,biology ,medicine.drug_class ,Phosphorus ,education ,Antibiotics ,chemistry.chemical_element ,010501 environmental sciences ,biology.organism_classification ,01 natural sciences ,Pollution ,Polyhydroxyalkanoates ,Nutrient ,Wastewater ,chemistry ,medicine ,Environmental Chemistry ,Food science ,Waste Management and Disposal ,Bacteria ,0105 earth and related environmental sciences ,medicine.drug - Abstract
Due to the widespread use of antibiotics in healthcare and livestock production, antibiotic resistance genes and residual antimicrobials would enter environment and further discharge into the municipal sewage system. The objective of this work was to explore the potential effect of chlortetracycline (CTC) on biological nutrient removal from wastewater. Thus, the effects of CTC on biological phosphorus and nitrogen removal were investigated with respect to the viability of bacteria, the activities of key metabolic enzymes, and the transformations of intermediate metabolites. Results showed that the presence of 0.1 mg·L−1 CTC did not show any impact on biological phosphorus and nitrogen removal. Nevertheless, the long-term exposure to 1 and 10 mg·L−1 CTC decreased TN removal efficiency from 77.4% to 64.1% and 53.4%, respectively. Meanwhile, the presence of 10 mg·L−1 CTC decreased the SOP removal efficiency from 96.3% to 78.1%. Mechanism studies indicated that CTC could affect the activities of reductase and the transformations of polyhydroxyalkanoates and glycogen, resulting in inhibition of denitrification and phosphorus uptake, which may be the major reason for the high level of CTC showing adverse influence on wastewater biological nutrient removal.
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- 2018
50. Hierarchically Porous Carbons Derived from Biomasses with Excellent Microwave Absorption Performance
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Wei Hu, Jingjing Wang, Ting Huang, Zhengchen Wu, Feifei Xie, Ke Tian, Lei Li, and Mengxing Su
- Subjects
Materials science ,Carbonization ,Reflection loss ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry ,Chemical engineering ,Nano ,General Materials Science ,0210 nano-technology ,Absorption (electromagnetic radiation) ,Porosity ,Carbon ,Microwave ,Microscale chemistry - Abstract
A variety of biomass-based carbon materials with two-level porous structure have been successfully prepared by one-step carbonization process. The first level of microscale pores templates from the inherent porous tissues, while the second one of nanopores is produced by the in situ etching by the embedded alkaline metal elements. The superimposed effect of nano and microscale pores endows the hierarchically porous carbons (HPCs) with excellent microwave absorption (MA) performance. Among them, the spinach-derived HPC exhibits a maximum reflection loss of −62.2 dB and a broad effective absorption bandwidth of 7.3 GHz. Particularly, this excellent MA performance can be reproduced using the biomass materials belonging to different families, harvested seasons, and origins, indicating a green and sustainable process. These encouraging findings shed the insights on the preparation of biomass-derived microwave absorbents with promising practical applications.
- Published
- 2018
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