122 results on '"Xiong, Liang"'
Search Results
2. Discovery of a Potent and Cell-Active Inhibitor of DNA 6mA Demethylase ALKBH1
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Xiong, Liang, Li, Feng, Guo, Yinping, Zhang, Jian, Xu, Ke, Xiong, Zijie, Tong, Aiping, Li, Linli, and Yang, Shengyong
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N6-Methyladenine (6mA) of DNA has emerged as a novel epigenetic mark in eukaryotes, and several 6mA effector proteins have been identified. However, efforts to selectively inhibit the biological functions of these effector proteins with small molecules are unsuccessful to date. Here we report the first potent and selective small molecule inhibitor (13h) of AlkB homologue 1 (ALKBH1), the only validated 6mA demethylase. 13hshowed an IC50of 0.026 ± 0.013 μM and 1.39 ± 0.13 μM in the fluorescence polarization (FP) and enzyme activity assay, respectively, and a KDof 0.112 ± 0.017 μM in the isothermal titration calorimetry (ITC) assay. The potency of 13hwas well explained by the cocrystal structure of the 13h-ALKBH1 complex. Furthermore, 13hdisplayed excellent selectivity for ALKBH1. In cells, compound 13hand its derivative 16were able to engage ALKBH1 and modulate the 6mA levels. Collectively, our study identified the first potent, isoform selective, and cell-active ALKBH1 inhibitor, providing a tool compound for exploring the biological functions of ALKBH1 and DNA 6mA.
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- 2024
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3. Establishment of an Efficient Expression and Regulation System in Streptomycesfor Economical and High-Level Production of the Natural Blue Pigment Indigoidine
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Zhao, Ming, Zhang, Xiu-Shan, Xiong, Liang-Bin, Liu, Kun, Li, Xiang-Fei, Liu, Yan, and Wang, Feng-Qing
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Indigoidine, as a kind of natural blue pigment, is widely used in textiles, food, and pharmaceuticals and is mainly synthesized from l-glutamine via a condensation reaction by indigoidine synthetases, most of which originates from Streptomycesspecies. However, due to the complex metabolic switches of Streptomyces, most of the researchers choose to overexpress indigoidine synthetases in the heterologous host to achieve high-level production of indigoidine. Considering the advantages of low-cost culture medium and simple culture conditions during the large-scale culture of Streptomyces, here, an updated regulation system derived from the Streptomycesself-sustaining system, constructed in our previous study, was established for the highly efficient production of indigoidine in Streptomyces lividansTK24. The updated system was constructed via promoter mining and σhrdBexpression optimization, and this system was applied to precisely and continuously regulate the expression of indigoidine synthetase IndC derived from Streptomyces albusJ1704. Finally, the engineered strain was cultured with cheap industrial glycerol as a supplementary carbon source, and 14.3 and 46.27 g/L indigoidine could be achieved in a flask and a 4 L fermentor, respectively, reaching the highest level of microbial synthesis of indigoidine. This study will lay a foundation for the industrial application of Streptomycescell factories to produce indigoidine.
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- 2024
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4. Effect of postural changes on in vivo pelvic tilt and functional component anteversion in total hip arthroplasty patients with lumbar disc degenerations
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Klemt, Christian, Limmahakhun, Sakkadech, Bounajem, Georges, Xiong, Liang, Yeo, Ingwon, and Kwon, Young-Min
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AimsThe complex relationship between acetabular component position and spinopelvic mobility in patients following total hip arthroplasty (THA) renders it difficult to optimize acetabular component positioning. Mobility of the normal lumbar spine during postural changes results in alterations in pelvic tilt (PT) to maintain the sagittal balance in each posture and, as a consequence, markedly changes the functional component anteversion (FCA). This study aimed to investigate the in vivo association of lumbar degenerative disc disease (DDD) with the PT angle and with FCA during postural changes in THA patients.MethodsA total of 50 patients with unilateral THA underwent CT imaging for radiological evaluation of presence and severity of lumbar DDD. In all, 18 patients with lumbar DDD were compared to 32 patients without lumbar DDD. In vivo PT and FCA, and the magnitudes of changes (ΔPT; ΔFCA) during supine, standing, swing-phase, and stance-phase positions were measured using a validated dual fluoroscopic imaging system.ResultsPT, FCA, ΔPT, and ΔFCA were significantly correlated with the severity of lumbar DDD. Patients with severe lumbar DDD showed marked differences in PT with changes in posture; there was an anterior tilt (-16.6° vs -12.3°, p = 0.047) in the supine position, but a posterior tilt in an upright posture (1.0° vs -3.6°, p = 0.005). A significant decrease in ΔFCA during stand-to-swing (8.6° vs 12.8°, p = 0.038) and stand-to-stance (7.3° vs 10.6°,p = 0.042) was observed in the severe lumbar DDD group.ConclusionThere were marked differences in the relationship between PT and posture in patients with severe lumbar DDD compared with healthy controls. Clinical decision-making should consider the relationship between PT and FCA in order to reduce the risk of impingement at large ranges of motion in THA patients with lumbar DDD.
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- 2024
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5. Two new eudesmane sesquiterpenoids with neuroprotective activity from Pogostemon cablin.
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Zheng, Qi, Ma, Chuan, Xiong, Liang, Peng, Cheng, Guo, Li, Guo, Da-Le, Zhao, E, Zhou, Qin-Mei, and Dai, Ou
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Two new eudesmane sesquiterpenoids [(−)-(1 R ,5 S ,6 R ,8 S)−1-hydroxy- nor -eudesm-11-ene-2-one (1) and (−)-(1 S ,5 S ,6 R ,8 R)−6-hydroxyeudesm-11-ene-2-one (2)] were isolated from the aerial parts of Pogostemon cablin. Compound 1 is an unusual 1- nor -eudesmane, and its skeleton structure is similar to that of compound 2. The molecular structures and absolute conformations of the two new sesquiterpenoids were determined by NMR spectroscopy, X-ray diffraction analysis, NMR data calculations and electronic circular dichroism (ECD) calculations. The neuroprotective activity of the isolates in an H 2 O 2 -induced PC12 cell model was also assessed, and the results show that both compounds exhibit good neuroprotective effects. [Display omitted] • Two new eudesmane sesquiterpenoids were isolated from Pogostemon cablin. • Their absolute configurations were elucidated by NMR data, X-ray diffraction, NMR data calculations and ECD calculations. • Compounds 1 and 2 may play a role in reducing the cytotoxicity of H 2 O 2 on PC12 cells. [ABSTRACT FROM AUTHOR]
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- 2023
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6. An Optimized Two-Dimensional Quantitative Nuclear Magnetic Resonance Strategy for the Rapid Quantitation of Diester-Type C19-Diterpenoid Alkaloids from Aconitum carmichaelii.
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Lin, Qiao, Meng, Chunwang, Liu, Jie, Liu, Fei, Zhou, Qinmei, Liu, Juan, Peng, Cheng, and Xiong, Liang
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- 2023
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7. Favorable Exploration Lithofacies and Their Formation Mechanisms in Lacustrine Shales Deposited under Different Salinity Conditions: Insights into Organic Matter Accumulation and Pore Systems
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Wang, Enze, Guo, Tonglou, Li, Maowen, Xiong, Liang, Dong, Xiaoxia, Wang, Tong, and Li, Hanqi
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Efficient identification of favorable exploration lithofacies with commercial value is of utmost importance in lacustrine shale petroleum exploration. Shales deposited under different salinity conditions exhibit considerably different organic matter (OM) accumulation and mineral compositions. However, the systematic summarization of favorable exploration lithofacies and their formation mechanisms in lacustrine shale systems formed under different salinity conditions is still lacking. Herein, lacustrine shale of the Lower Jurassic Qianfoya Formation (J1q) from the Langzhong Area of the Sichuan Basin is studied to systematically reveal its OM accumulation mechanisms and the factors controlling its physical properties. By combining our data with that published in the literature, the favorable exploration lithofacies and their formation mechanisms in lacustrine shales deposited under various different salinities (i.e., freshwater, saline, and hypersaline) are discussed. Our findings indicate that the J1q shale comprises four lithofacies, namely, organic-lean mixed shale (LM), organic-lean argillaceous shale (LCM), organic-rich mixed shale (RM), and organic-rich argillaceous shale (RCM). The pore systems of RCM and RM are dominated by OM-related pores, whereas those of LCM and LM are dominated by clay mineral-related pores. The J1q shale was deposited in an oxic environment with a semiarid to semihumid climate, moderate weathering, and freshwater to brackish conditions. The OM content is primarily influenced by the relatively reductive environment. The physical properties of RCM and RM are primarily determined by the total organic carbon (TOC) content, whereas those of LCM and LM are determined by the clay mineral content. Additionally, a novel model for describing the change in the TOC content, pore system characteristics, and fracability of shale with an increase in salinity is proposed. The model shows that with an increase in salinity, the TOC content first decreases, then increases, and finally decreases. Simultaneously, there is an improvement in the proportion of framework-grain related pores within the pore system. RCM, RM, and tight sandstone and limestone interlayers within freshwater lacustrine shale can be regarded as primary sweet spots. In the saline and hypersaline lacustrine shale systems, the main exploration targets are RM and organic-rich calcareous shale. These observations provide theoretical guidance for locating sweet spots in lacustrine shale systems deposited under different salinity conditions.
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- 2023
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8. Favorable Exploration Lithofacies and Their Formation Mechanisms in Lacustrine Shales Deposited under Different Salinity Conditions: Insights into Organic Matter Accumulation and Pore Systems.
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Wang, Enze, Guo, Tonglou, Li, Maowen, Xiong, Liang, Dong, Xiaoxia, Wang, Tong, and Li, Hanqi
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- 2023
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9. Effects of Hydrogen Charging on Mechanical Properties of CLAM Steel at Different Strain Rates
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Gu, Yue-Yang, Zhao, Han-Yu, Chen, Wei, Yan, Wei, Xiong, Liang-Yin, and Chen, De-Min
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The China low-activation martensitic (CLAM) steel has been proposed as a candidate structural material for nuclear fusion reactors. It is essential to study the influence of hydrogen charging and strain rate on the tensile behavior of CLAM steel considering its service environment. In this study, CLAM steel was investigated using tensile tests operated at room temperature before and after hydrogen charging. The results showed that the elongation loss increased significantly with the increase of the hydrogen charging current density at either a low or a high strain rate, which is related to the hydrogen content in the steel. The hydride was systematically studied, including the morphology and the thermal stability as well as the effects on mechanical properties. The possible mechanism of the formation of hydride during hydrogen charging has been analyzed based on the interaction between alloying elements and hydrogen.
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- 2023
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10. Theory and practice of unconventional gas exploration in carrier beds: Insight from the breakthrough of new type of shale gas and tight gas in Sichuan Basin, SW China.
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GUO, Tonglou, XIONG, Liang, YE, Sujuan, DONG, Xiaoxia, WEI, Limin, and YANG, Yingtao
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- 2023
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11. Lithofacies and pore features of marine-continental transitional shale and gas enrichment conditions of favorable lithofacies: A case study of Permian Longtan Formation in the Lintanchang area, southeast of Sichuan Basin, SW China.
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WANG, Enze, GUO, Tonglou, LIU, Bo, LI, Maowen, XIONG, Liang, DONG, Xiaoxia, ZHANG, Nanxi, and WANG, Tong
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- 2022
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12. New sesquineolignan glycoside isomers from the aerial parts of Leonurus japonicus and their absolute configurations.
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Bu, Lan, Zhou, Qin-Mei, Peng, Cheng, Shu, Hong-Zhen, Zhou, Fei, Wu, Guang-Xu, Liu, Fei, Tian, Hui, and Xiong, Liang
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[Display omitted] The acid water-soluble fraction of the 95% EtOH extract of Leonurus japonicus exhibited significant anti-inflammatory activity by suppressing the p-ERK/ERK ratio and iNOS expression. A further phytochemical investigation of this acid water-soluble fraction led to the isolation of three previously undescribed sesquineolignan glycosides, leolignosides A–C (1 – 3), and their planar structures were elucidated using HR-ESI-MS and 1D and 2D NMR. To determine the complicated absolute configuration of sesquineolignan glycosides, coupling constants, NOESY data, empirical rules, enzymatic hydrolysis, and ECD data were comprehensively used. These isolated compounds were also screened for anti-inflammatory activity. Encouragingly, leolignosides A–C all suppressed LPS-induced NO overproduction in RAW 264.7 macrophages. The aglycone (3a) of leolignoside C was chosen for further investigation for its activity and the available amount. Similar to the acid water-soluble fraction, compound 3a inhibited NO overproduction and decreased the p-ERK/ERK and p-NF-κB/NF-κB ratios, indicating that 3a may exert anti-inflammatory effects through the ERK/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]
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- 2024
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13. A Fully-Integrated Wideband Digital Polar Transmitter With 11-bit Digital-to-Phase Converter in 40nm CMOS
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Hu, Chunxiao, Yin, Yun, Li, Tong, Liu, Yangzi, Xiong, Liang, and Xu, Hongtao
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This work presents a wideband digital polar transmitter (DPTX) with an integrated capacitor-digital-to-analog converter (C-DAC)-based digital-to-phase converter (DPC). A normalized CORDIC algorithm is introduced to convert the
$I/Q$ $1.4 \times 1.4$ - Published
- 2023
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14. Enrichment mechanism and resource potential of shale-type helium: A case study of Wufeng Formation-Longmaxi Formation in Sichuan Basin
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Nie, Haikuan, Liu, Quanyou, Dang, Wei, Li, Pei, Su, Haikun, Bao, Hanyong, Xiong, Liang, Liu, Zhujiang, Sun, Chuanxiang, and Zhang, Peixian
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China’s helium resource is highly dependent on overseas imports. Organic-rich and U/Th-rich shale reservoirs generally contain helium, and although the helium content is low, the total reserve is large. Therefore, the effective development and utilisation of shale-type helium resources is a realistic way to improve the security of helium resources in China. In this study, the generation mechanism, helium source and content, migration modes and pathways, controlling factors of enrichment, distribution pattern, and resource potential of the helium were analysed, using the Wufeng-Longmaxi shale in the Sichuan Basin and its periphery. Furthermore, countermeasures were proposed for shale-type helium exploration and development. The results show that the Wufeng-Longmaxi shale has a high content of U and Th and a good ability to generate helium. The helium is generated by a typical crustal source of helium and is characterised by self-generation, self-storage, and wide distribution. The helium resource potential is a product of its content and the resources of the associated natural gas. The continuous supply of helium and effective preservation are the main geological factors that control the enrichment of shale-type helium. The preliminary evaluation results show that the reserves of helium in proven shale gas reserves are 10.8×108m3in the Sichuan Basin and its periphery, where the extra-large helium fields are likely to be discovered. Additionally, 0.0912×108m3of helium was produced, along with the annual production of shale gas. To avoid the waste of helium and to improve the self-supply ability, it is suggested that research on the resource potential, enrichment mechanism, and distribution pattern of shale-type helium should be carried out as soon as possible, and helium extraction techniques for helium-bearing natural gas should be studied.
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- 2023
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15. Depositional Environment Variation and Organic Matter Accumulation Mechanism of Marine–Continental Transitional Shale in the Upper Permian Longtan Formation, Sichuan Basin, SW China.
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Wang, Enze, Guo, Tonglou, Li, Maowen, Xiong, Liang, Dong, Xiaoxia, Zhang, Nanxi, and Wang, Tong
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- 2022
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16. Pocahemiketone A, a Sesquiterpenoid Possessing a Spirocyclic Skeleton with a Hemiketal Endoperoxide Unit, Alleviates Aβ25–35-Induced Pyroptosis and Oxidative Stress in SH-SY5Y Cells.
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Zhou, Qin-Mei, Zhao, Hao-Yu, Ma, Chuan, Huang, Lu, Liu, Jie, Guo, Li, Peng, Cheng, and Xiong, Liang
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- 2022
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17. Architecture Design and Ground Performance of Netherlands‐China Low‐Frequency Explorer
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Karapakula, Sukanth, Brinkerink, Christiaan, Vecchio, Antonio, Pourshaghaghi, Hamid R., Dolron, Peter, Jordans, Roel, Bertels, Eric, Aalbers, Gerard, Ruiter, Mark, Boonstra, Albert J., Bentum, Mark, Prinsloo, David, Arts, Michel, Bast, Jeanette, Damstra, Sieds, Duin, Albert, Ebbendorf, Nico, Marel, Hans, Morawietz, Juergen, Witvers, Roel, Poiesz, Wietse, Dongen, Rico, Cecconi, Baptiste, Zarka, Philippe, Dekkali, Moustapha, Chen, Linjie, Wang, Mingyuan, Zhang, Mo, Huang, Maohai, Yan, Yihua, Dong, Liang, Tan, Baolin, Zhang, Lihua, Xiong, Liang, Sun, Ji, Zhang, Hongbo, Ping, Jinsong, Wolt, Marc Klein, and Falcke, Heino
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The Netherlands‐China Low‐Frequency Explorer (NCLE) (Boonstra et al., 2017, https://www.ursi.org/proceedings/procGA17/papers/Paper_J19‐2(1603).pdf; Chen et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AAS…23610203C/abstract) is a radio instrument for astrophysical studies in the low‐frequency range (80 kHz–80 MHz). As a technology demonstrator, NCLE shall inform the design of future radio receivers that aim at low‐frequency radio astronomy. NCLE can make observations at very high spectral resolution (<1 kHz) and generate radio sky maps at an angular resolution of ≈1.5 radians. NCLE uses three monopole antennas, each 5 m long, and three identical analog signal chains to process the signal from each antenna. A single digital receiver samples the signal and calculates the auto‐correlated and cross‐correlated spectra. The instrument's analog and digital signal chains are extensively configurable. They can be fine‐tuned to produce broadband spectra covering the instrument's complete operating frequency range or sub‐bands. NCLE was developed within a veryshort timescale of 2 years, and currently, it is on board Queqiao, the relay spacecraft of the Chang'e‐ 4 mission, in a halo orbit around the Earth‐Moon L2 point. This paper outlines the science cases, instrument architecture with focus on the signal chain, and discusses the laboratory measurements during the pre‐launch phase. Radio observations from the Moon at very low frequenciesRadio instrument technology demonstration for future lunar observatory and interferometryRadio receiver design for low‐frequency observation Radio observations from the Moon at very low frequencies Radio instrument technology demonstration for future lunar observatory and interferometry Radio receiver design for low‐frequency observation
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- 2024
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18. PM2.5 exposure-induced senescence-associated secretory phenotype in airway smooth muscle cells contributes to airway remodeling.
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Cheng, Pei-Pei, Yu, Fan, Chen, Shuai-Jun, Feng, Xiao, Jia, Zi-Heng, Hu, Shi-He, Cui, Xiao-Lin, Zhou, Ya-Ya, Niu, Qian, Liang, Li-Mei, Wang, Meng, Song, Lin-Jie, He, Xin-Liang, Xiong, Liang, Xiang, Fei, Wang, Xiaorong, Ma, Wan-Li, and Ye, Hong
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PARTICULATE matter ,SMOOTH muscle ,MUSCLE cells ,CHRONIC obstructive pulmonary disease ,AIRWAY (Anatomy) - Abstract
Fine particulate matter (PM2.5) has been linked to increased severity and incidence of airway diseases, especially chronic obstructive pulmonary disease (COPD) and asthma. Airway remodeling is an important event in both COPD and asthma, and airway smooth muscle cells (ASMCs) are key cells which directly involved in airway remodeling. However, it was unclear how PM2.5 affected ASMCs. This study investigates the effects of PM2.5 on airway smooth muscle and its mechanism. We first showed that inhaled particulate matter was distributed in the airway smooth muscle bundle, combined with increased airway smooth muscle bundle and collagen deposition in vivo. Then, we demonstrated that PM2.5 induced up-regulation of collagen-I and alpha-smooth muscle actin (α-SMA) expression in rat and human ASMCs in vitro. Next, we found PM2.5 led to rat and human ASMCs senescence and exhibited senescence-associated secretory phenotype (SASP) by autophagy-induced GATA4/TRAF6/NF-κB signaling, which contributed to collagen-I and α-SMA synthesis as well as airway smooth muscle remodeling. Together, our results provided evidence that SASP induced by PM2.5 in airway smooth muscle cells prompted airway remodeling. [Display omitted] • Inhaled particular matter induced airway smooth muscle remodeling. • PM2.5 led to ASMCs senescence and exhibited senescence-associated secretory phenotype (SASP). • SASP contributed to collagen-I and α-SMA synthesis as well as airway smooth muscle remodeling. • Inhibition of SASP prevented PM2.5-induced airway remodeling. [ABSTRACT FROM AUTHOR]
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- 2024
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19. In vitro and in vivo assessment of the effect of biodegradable magnesium alloys on osteogenesis.
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Li, Ding, Zhang, Dechuang, Yuan, Qi, Liu, Lihong, Li, Hui, Xiong, Liang, Guo, Xiaoning, Yan, Yang, Yu, Kun, Dai, Yilong, Xiao, Tao, Li, Yuncang, and Wen, Cuie
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MAGNESIUM alloys ,FIBROBLAST growth factor receptors ,BONE morphogenetic proteins ,BONE growth ,MESENCHYMAL stem cells ,FEMORAL fractures - Abstract
Magnesium (Mg) and some of its alloys are considered promising biodegradable metallic biomaterials for bone implant applications. The osteogenesis effect of Mg alloys is widely reported; however, the underlying mechanisms are still not clear. In this study, pure Mg, Mg-3Zn, and Mg-2Zn-1Mn were prepared, and their degradation behavior, biocompatibility, and osteogenesis effect were systematically assessed both in vitro and in vivo. Primary rat bone marrow-derived mesenchymal stem cells (BMSCs) were used to evaluate the biocompatibility of the prepared Mg alloys, and a rat femur fracture model was used to assess the stimulating effect of these alloys on bone-tissue formation. Mg-2Zn-1Mn showed higher corrosion resistance and more stable degradation behavior than pure Mg and Mg-3Zn. Extracts of the three materials showed significant stimulating effects on osteogenic differentiation of BMSCs along with non-cytotoxicity. Implantation of Mg-2Zn-1Mn wires into the femur of rats demonstrated superior histocompatibility, stable degradation, and notable promotion of osteogenesis without systemic toxicity. Moreover, the results of both in vitro and in vivo assessments demonstrated that bone morphogenetic proteins and fibroblast growth factor receptors are involved in the stimulating effect of Mg alloys. This work reports the degradation behavior, biocompatibility, and osteogenic effect of pure Mg and Mg-3Zn and Mg-2Zn-1Mn alloys in both in vitro and in vivo conditions. Mg-2Zn-1Mn showed higher corrosion resistance and more stable degradation behavior than pure Mg and Mg-3Zn. The extracts of the three materials showed a significant stimulating effect on osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs) along with non-cytotoxicity. Mg-2Zn-1Mn wires implanted into the femur of rats showed good histocompatibility, stable degradation, and notable promotion of osteogenesis without systemic toxicity. The results of the present study suggest that bone morphogenetic proteins (BMPs) and fibroblast growth factor receptors (FGFRs) are involved in the stimulating effect of Mg alloys on osteogenesis. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2022
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20. Bioactive neolignans and lignans from the roots of Paeonia lactiflora.
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XIA, Huan, ZHANG, Jing-Fang, WANG, Ling-Yan, XIA, Gui-Yang, WANG, Ya-Nan, WU, Yu-Zhuo, LIN, Peng-Cheng, XIONG, Liang, and LIN, Sheng
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Two new neolignans and one new lignan (1–3) were obtained from the roots of Paeonia lactiflora. Their structures were unambiguously elucidated based on extensive spectroscopic analysis, single-crystal X-ray crystallography, and the calculated and experimental electronic circular dichroism (ECD) spectra. Compound 1 was a racemic mixture and successfully resolved into the anticipated enantiomers via chiral-phase HPLC. Compound 3 demonstrated moderate inhibitory activity against human carboxylesterase 2A1 (hCES2A1) with an IC 50 value of 7.28 ± 0.94 μmol·
−1 . [ABSTRACT FROM AUTHOR]- Published
- 2022
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21. Experimental research on the critical conditions and critical equation of chip splitting when turning a C45E4 disc workpiece symmetrically with a high-speed steel double-edged turning tool
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Xu, Ming-Xian, Xiong, Liang-Shan, Zhu, Bao-Yi, Zheng, Ling-Feng, and Yin, Kai
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Chip splitting is a natural chip separation phenomenon that can significantly reduce cutting energy consumption. To reveal its occurrence mechanisms, a method for obtaining its critical conditions through cutting experiments and establishing its critical equation is proposed in this paper. Based on previous research results regarding the relationship between chip removal interference and chip splitting, the control variables that affect chip splitting are identified by analyzing a geometric model of the cutting process. A total of 366 experiments on turning a C45E4 disc workpiece with a high-speed steel double-edged turning tool based on the dichotomy method were conducted and 51 experimental data on chip splitting critical conditions were obtained. According to these experimental data, a critical equation expressed by a finite-degree polynomial with a cutting thickness equal to the other control variables was fitted. By analyzing the critical surface, it was determined that chip splitting followed a law in which the smaller the cutting thickness and the larger the absolute value of the negative rake angle, edge angle, and edge inclination of the tool, the more likely chip splitting was to occur. Through a verification experiment, it was determined that the derived critical equation could accurately predict the occurrence of 95.24% of chip splitting. It was also determined that the occurrence of chip splitting led to a cliff-like drop in the specific total cutting force with a maximum drop of 51.23%. This research lays a foundation for the rational utilization of chip splitting in tool structure parameter design and cutting parameter energy saving optimization.
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- 2022
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22. Accurate identification of low-resistivity gas layer in tight sandstone gas reservoirs based on optimizable neural networks
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Feng, Shaoke, Xiong, Liang, Radwan, Ahmed E., Xie, Runcheng, Yin, Shuai, and Zhou, Wen
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In tight sandstone reservoirs, low resistivity gas reservoirs have a certain gas production capacity, but their reservoir resistivity value is less than 20 Ω m, or their ratio to water layer resistivity is less than 2. Therefore, the identification of low resistivity gas reservoirs is a prominent problem that needs to be resolved. In this paper, on the basis of traditional experimental analysis, NMR experiments and wettability experiments were conducted. The high bound water saturation and pore fractal dimension have a significant impact on reservoir resistivity. After various experimental analysis results were preprocessed by the image pool and data pool, an optimized neural network (ONN) classification model was established based on deep learning theory. The confusion matrix result (training datasets) was 87.13%, and the ROC area of low resistivity gas layers was close to 1, indicating good recognition performance for low resistivity gas layers. The model was used to identify the properties of the J4 well reservoir section. The identification result was consistent with the actual logging resistivity values (low resistivity) and testing conclusions (gas layer). This model can accurately identify low resistivity gas reservoirs in the research area, and has important guiding significance for identifying the reservoir properties of tight sandstone gas reservoirs in the Sichuan Basin. It can provide reference value for the exploration and development of similar gas reservoirs in other regions.
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- 2024
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23. Engineering Mycolicibacterium neoaurumfor the production of antioxidant ergothioneine
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Xiong, Liang-Bin, Xie, Zhi-Yong, Ke, Jie, Wang, Li, Gao, Bei, Tao, Xin-Yi, Zhao, Ming, Shen, Ya-Ling, Wei, Dong-Zhi, and Wang, Feng-Qing
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Ergothioneine (EGT) represents valuable protective functions for humans, but EGT from the diet cannot meet daily requirements. Although the heterologous synthesis of EGT had been achieved, it is still a challenge to obtain stable and high-yield EGT-producing cell factories. Here, after the co-overexpression of the EGT synthetic gene cluster and hisG, hisC, and allB1in Mycolicibacterium neoaurum, the natural EGT titer was increased by 7.2-folds. However, the degradation problem of EGT in large-scale fermentation needs to be urgently solved. A putative lyase gene Mn_3042was inactivated, thus inhibiting the product degradation and increasing the EGT titer by 21%. Moreover, the enhancement of S-adenosyl- l-methionine regeneration further increased EGT titer by 28%. After optimization of fed-batch fermentation, the yield of EGT was boosted to 1.56?g/L with a productivity of 7.2?mg/L/h. This study provides a systematic engineering strategy for developing EGT-producing cell factories. M. neoaurumwas systematically engineered to produce ergothioneine.Regulating of a lyase and SAM regeneration boosted the production of ergothioneine.The engineered M. neoaurumrealized the production of 1.56?g/L ergothioneine. M. neoaurumwas systematically engineered to produce ergothioneine. Regulating of a lyase and SAM regeneration boosted the production of ergothioneine. The engineered M. neoaurumrealized the production of 1.56?g/L ergothioneine.
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- 2022
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24. Minority Race and Ethnicity is Associated With Higher Complication Rates After Revision Surgery for Failed Total Hip and Knee Joint Arthroplasty.
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Klemt, Christian, Walker, Paul, Padmanabha, Anand, Tirumala, Venkatsaiakhil, Xiong, Liang, and Kwon, Young-Min
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Background: Racial and ethnic disparities in access to hip and knee total joint arthroplasty (TJA) and postoperative outcomes have wide-reaching implications for patients and the health care system. The aim of this study is to evaluate the effect of ethnicity on clinical outcomes and complications following revision hip and knee TJA.Methods: A single-institution, retrospective analysis of a consecutive series of 4424 revision hip and knee TJA patients was evaluated. Student's t-test and chi-squared analysis were used to identify significant differences in patient demographics and clinical outcomes between Caucasians and various ethnic minorities, including African Americans, Hispanics, and Asians.Results: When compared with white patients, African American patients demonstrated a significantly higher BMI (P = .04), ASA score (P = .04), length of hospital stay (P = .06), and postoperative infection rates (P = .04). Hispanics demonstrated a significantly higher BMI (P = .04), when compared with white patients, alongside a significantly higher risk for postoperative infection (P < .01). African American demonstrated a significantly higher ASA score (P = .02; P = .03), when compared with Hispanics and Asians, alongside a significantly increased length of stay (P = .01) and higher risk for postoperative infection (P = .02).Conclusion: The study findings demonstrate an underutilization of revision TJA by ethnic minority groups, suggesting that disparities in access to orthopedic surgery increase from primary to revision surgery despite higher failure rates of minority ethnic groups reported after primary TJA surgery. In addition, inferior postoperative outcomes were associated with African Americans and Hispanics, when compared to white patients, with African Americans demonstrating the highest risk of postoperative complications. [ABSTRACT FROM AUTHOR]- Published
- 2021
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25. Determination of the absolute configurations and anti-angiogenic activities of new diarylheptanoid glucosides from Curcuma phaeocaulis.
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Li, Cheng-Zhe, Peng, Cheng, Li, Xiao-Cui, Wu, Guang-Xu, Shu, Hong-Zhen, Wang, Fang, Liu, Fei, and Xiong, Liang
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Diarylheptanoids, potential therapeutic agents and dietary supplements, are the main active compounds in the genus Curcuma , however, determination of the absolute configurations of the flexible polyhydric main chains in linear diarylheptanoids is still a challenge. In this study, an exploration of the phytochemical constituents of Curcuma phaeocaulis led to the isolation of eight novel linear diarylheptanoids (1 – 8). Enzymatic hydrolysis, preparation of acetonide derivatives, preparation of MTPA esters, and electronic circular dichroism calculations were comprehensively performed in order to determine their absolute configurations. In in vitro assays, compounds 2 , 3 , and 6 exhibited anti-angiogenic activities, and compounds 2 , 3 , and their aglycones inhibited the proliferation of HepG2 cells. These findings suggest that diarylheptanoid glucosides of C. phaeocaulis may be useful for suppression of hepatoma growth and metastasis. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Outcome of Revision Surgery for the Idiopathic Stiff Total Knee Arthroplasty.
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Xiong, Liang, Klemt, Christian, Yin, Jonathan, Tirumala, Venkatsaiakhil, and Kwon, Young-Min
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Background: Idiopathic stiff total knee arthroplasty (TKA) represents one of the most challenging subsets of the stiff TKA, as the etiology is unknown and there is no consensus on the most appropriate surgical treatment modality. Therefore, the aim of this study is to report on postoperative outcomes of revision surgery for idiopathic stiff TKA.Methods: We retrospectively reviewed 189 consecutive patients (202 knees) who underwent revision TKA for stiffness: (1) 101 knees in the idiopathic stiffness cohort and (2) 88 in the non-idiopathic stiffness cohort. In the idiopathic stiffness cohort, 42 knees underwent isolated tibial insert exchange and 59 knees underwent component revision. Perioperative knee range of movement and complications were analyzed.Results: The overall revision surgery outcomes of the idiopathic stiffness cohort were worse than those of the non-idiopathic stiffness cohort with regard to maximum flexion (91.7° vs 100.1°, P = .02) and flexion range of motion (ROM) (87.6° vs 97.1°, P = .01). In the idiopathic stiffness cohort, isolated tibial insert exchange demonstrated greater maximum flexion (96.8° vs 88.4°, P = .06) and flexion ROM (93.2° vs 83.9°, P = .07). In terms of re-revision rates, the isolated tibial insert exchange idiopathic stiffness cohort demonstrated lower re-revision rates compared to the component revision idiopathic stiffness cohort (16.7% vs 31.0%, P = .01).Conclusion: This study demonstrates that the overall revision surgery outcome of idiopathic stiff TKA is worse than non-idiopathic TKA stiffness. In idiopathic stiffness cohorts, isolated tibial insert exchange was associated with lower re-revision rates than component revision, with similar efficacy in improving ROM, suggesting that isolated tibial insert exchange may be a preferred surgical treatment option in TKA patients with idiopathic stiffness. [ABSTRACT FROM AUTHOR]- Published
- 2021
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27. Concomitant Hip and Knee Periprosthetic Joint Infection in Periprosthetic Fracture: Diagnostic Utility of Serum and Synovial Fluid Markers.
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van den Kieboom, Janna, Tirumala, Venkatsaiakhil, Xiong, Liang, Klemt, Christian, and Kwon, Young-Min
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Background: Diagnosing periprosthetic joint infection (PJI) in patients with a periprosthetic fracture can be challenging due to concerns regarding the reliability of commonly used serum and synovial fluid markers. This study aimed at determining the diagnostic performance of serum and synovial fluid markers for diagnosing PJI in patients with a periprosthetic fracture of a total joint arthroplasty.Methods: A total of 144 consecutive patients were included: (1) 41 patients with concomitant PJI and periprosthetic fracture and (2) 103 patients with periprosthetic fracture alone. Serum markers erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and synovial markers white blood cell (WBC) count and polymorphonuclear percentage were assessed.Results: ESR demonstrated 87% sensitivity and 48% specificity at the Musculoskeletal Infection Society threshold, area under the curve (AUC) of 0.74, and optimal threshold of 45.5 mm/h (76% sensitivity, 68% specificity). CRP showed 94% sensitivity and 40% specificity, AUC of 0.68 with optimal threshold of 16.7 mg/L (84% sensitivity, 51% specificity). Synovial WBC count demonstrated 87% sensitivity and 78% specificity, AUC of 0.90 with optimal threshold of 4552 cells/μL (86% sensitivity, 85% specificity). Polymorphonuclear percentage showed 79% sensitivity and 63% specificity, AUC of 0.70 with optimal threshold of 79.5% (74% sensitivity, 63% specificity). The AUC of all combined markers was 0.90 with 84% sensitivity and 79% specificity.Conclusion: The diagnostic utility of the serum and synovial markers for diagnosing PJI was lower in the setting of concomitant periprosthetic fracture compared to PJI alone. Using the Musculoskeletal Infection Society thresholds, ESR, CRP, and WBC count showed high sensitivity, yet low specificity, thus higher thresholds and utilizing all serum and synovial markers in combination should be considered. [ABSTRACT FROM AUTHOR]- Published
- 2021
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28. Diagnostic Utility of Platelet Count/Lymphocyte Count Ratio and Platelet Count/Mean Platelet Volume Ratio in Periprosthetic Joint Infection Following Total Knee Arthroplasty.
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Tirumala, Venkatsaiakhil, Klemt, Christian, Xiong, Liang, Chen, Wenhao, van den Kieboom, Janna, and Kwon, Young-Min
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Background: Diagnosing a periprosthetic joint infection (PJI) can be challenging and often requires a combination of clinical and laboratory findings. Monocyte/lymphocyte ratio, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio (PLR), and platelet/mean platelet volume ratio (PVR) are simple predictors for inflammation that can be readily obtained from complete blood count. The aim of this study is to evaluate the diagnostic utility of these markers in predicting PJI in total knee arthroplasty (TKA) patients.Methods: A total of 538 patients who underwent revision TKA with calculable marker ratios prerevision in 2 groups were evaluated: (1) 206 patients with a preoperative diagnosis of PJI (group I) and (2) 332 patients treated for revision TKA for aseptic failures (group II). The diagnostic abilities of the markers were assessed via receiver operator characteristic curve analysis.Results: The optimal threshold of PVR at 30.82 had the highest sensitivity of 87.7%, while the optimal threshold of PLR at 234.13 had the highest specificity of 82.5%. Both PLR and PVR, when combined with Musculoskeletal Infection Society thresholds for erythrocyte sedimentation rate, C-reactive protein, synovial WBC, and PMN%, achieve significantly higher sensitivity and specificity rates for PJI at or above 97% (PLR: 99.03%; 98.80%; PVR: 98.54%;97.89%).Conclusion: Our study demonstrates that PVR and PLR, which are readily available and inexpensive to obtain from complete blood counts, when combined with serum and synovial fluid markers have increased sensitivity and specificity comparable to that of alpha defensin. This suggests that PVR and PLR can be used together with other hematologic and aspirate markers to increase the accuracy of PJI diagnosis in TKA patients. [ABSTRACT FROM AUTHOR]- Published
- 2021
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29. Single-Stage Revision of the Infected Total Knee Arthroplasty Is Associated With Improved Functional Outcomes: A Propensity Score-Matched Cohort Study.
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Klemt, Christian, Tirumala, Venkatsaiakhil, Oganesyan, Ruben, Xiong, Liang, van den Kieboom, Janna, and Kwon, Young-Min
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Background: Single-stage revision is an alternative to the standard 2-stage revision, potentially minimizing morbidities and improving functional outcomes. This study aimed at comparing single-stage and 2-stage revision total knee arthroplasty (TKA) for chronic periprosthetic joint infection (PJI) with regard to patient-reported outcome measures (PROMs) and complication rates.Methods: A total of 185 consecutive revision TKA patients for chronic PJI with complete preoperative and postoperative PROMs were investigated. A total of 44 patients with single-stage revision TKA were matched to 88 patients following 2-stage revision TKA using propensity score matching, yielding a total of 132 propensity score-matched patients for analysis. Patient demographics and clinical information including reinfection and readmission rates were evaluated.Results: There was no significant difference in preoperative PROMs between propensity score-matched single-stage and 2-stage revision TKA cohorts. Postoperatively, significantly higher PROMs for single-stage revision TKA were observed for Knee disability and Osteoarthritis Outcome Score physical function (62.2 vs 51.9, P < .01), physical function short form 10A (42.8 vs 38.1, P < .01), PROMIS SF Physical (44.8 vs 41.0, P = .01), and PROMIS SF Mental (50.5 vs 47.1, P = .02). There was no difference between propensity score-matched single-stage and 2-stage revision TKA cohorts for clinical outcomes including reinfection rates (25.0% vs 27.2%, P = .78) and 90-day readmission rates (22.7% vs 25.0%, P = .77).Conclusion: This study illustrated that single-stage revision TKA for chronic PJI may be associated with superior patient-reported outcomes compared to 2-stage revision for the infected TKA using a variety of PROMs. Improved PROMs were not accompanied by differences in complication rates between both cohorts, suggesting that single-stage revision TKA may provide an effective alternative to 2-stage revision in patients with chronic TKA PJI. [ABSTRACT FROM AUTHOR]- Published
- 2021
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30. Outcome and Risk Factors Associated with Failures of Isolated Bearing Exchange for Osteolysis in Well-Fixed Cementless Total Hip Arthroplasty.
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Chen, Wenhao, Klemt, Christian, Padmanabha, Anand, Tirumala, Venkatsaiakhil, Xiong, Liang, and Kwon, Young-Min
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Background: It is often challenging to decide whether to revise only the bearing or femoral acetabular component in the setting of progressive osteolysis without component loosening in revision total hip arthroplasty (THA). In this study, we aimed to (1) compare the survivorship of isolated bearing exchange and single/both component revision for patients with periprosthetic osteolysis without component loosening, and (2) identify potential risk factors associated with failures of isolated bearing exchange.Methods: A total of 228 consecutive cases of revision THA for progressive osteolysis without component loosening was evaluated in 2 groups: (1) 124 component revision and (2) 104 isolated bearing exchange. The primary outcome was survival, with failure defined as repeat revision or reoperation for any reason. Patient risk factors, such as demographics and medical comorbidities, were also analyzed.Results: There was no significant difference in survivorship between the component revision group and the bearing exchange group at 10 years (85% vs 82%; P = .89). There was no progression of osteolysis on radiographs at last follow-up for patients with isolated bearing change. Univariate regression modeling demonstrated that renal disease was associated with failure of isolated bearing exchange after revision THA.Conclusion: This study demonstrated that isolated bearing exchange is associated with similar outcomes compared with component revision for aseptic osteolysis without loosening, demonstrating that isolated bearing exchange is a viable option for selected patients with osteolysis in the setting of well-fixed THA components. This provides clinically useful information for surgeons in the surgical treatment of THA patients with wear and osteolysis without component loosening. [ABSTRACT FROM AUTHOR]- Published
- 2021
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31. Study on the Size Distribution and Similarity Law of Bubble Nuclei in Water
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Yao, Xiong-liang, Li, Zhi-peng, Sun, Long-quan, and Chen, Wei-chu
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To study the distribution characteristics and similarity laws of nuclei under different pressures, based on the self-designed decompression chamber and the acoustic measuring system, the size distributions of nuclei in the degassed tap water under negative ambient pressures were measured. A number density distribution function of nuclei based on the modified Weibull distribution function was proposed and verified by the experimental measurement results and some published data of nuclei size distribution. Based on this nuclei number density distribution function, the similarity law of the nuclei size distribution was analyzed: in the scale experiment, the value of exponential in the similarity law of the nuclei number density should be determined by the nuclei size distribution of the water in the prototype experiment and the actual nuclei size distribution of the water in the model experiment. And a precondition is that the nuclei size distributions are similar.
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- 2021
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32. MOF-derived Cu based materials as highly active catalysts for improving hydrogen storage performance of Mg-Ni-La-Y alloys
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Liu, Yufei, Xiong, Liang, Gao, Bingyang, Shi, Qingyun, Wang, Ying, Han, Zhiya, Zhang, Zhenhua, Ma, Zhaowei, Wang, Limin, and Cheng, Yong
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Higher initial (de)hydrogenation temperature and sluggish kinetics are the main bottlenecks to develop Mg-based hydrogen storage alloys with high hydrogen capacity. One of the effective methods of solving these problems is introducing additives to enhance (de)hydrogenation kinetics and decrease particle sizes to lower (de)hydrogenation temperatures. In this work, Mg85-Ni10-La4.5-Y0.5 alloy doped with Cu@C nanoparticles is prepared, which could enhance (de)hydrogenation kinetics via introducing Cu nanoparticles as a catalyst and reduce the alloy particle sizes via acting as a grinding agent to lower (de)hydrogenation temperature. The results indicate the dehydrogenation temperature of the modified Mg85-Ni10-La4.5-Y0.5 composite could be decreased to 308.5°C, absorb 4.73 wt% H2at 220°C within 1 min and release 5.01 wt% H2within 4 min at 300°C. Moreover, the capacity retention could be maintained around 98.8 % after 10 cycles at 300°C, superior than those of Mg85-Ni10-La4.5-Y0.5 and milled-Mg85-Ni10-La4.5-Y0.5. DFT results and characterizations suggest that in-situformed Mg2Cu could accelerate the dissociation of Mg-H bonds and the presence of amorphous carbon in Mg-Ni-La-Y-Cu system will further synergistically improve the (de)hydrogenation kinetics of Mg85-Ni10-La4.5-Y0.5. Reduced particle sizes under the aid of carbon frameworks also help introduce boundaries of the particles and shorten hydrogen diffusion pathways.
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- 2024
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33. Extreme lateral interbody fusion and percutaneous pedicle screw fixation in the minimally invasive treatment of thoracic tuberculosis
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Deng, Liang, Zhang, Yuan-Wei, Xiong, Liang-Yu, Zhang, Su-Li, Ni, Wen-Yan, and Xiao, Qiang
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Objective As a minimally invasive intervertebral fusion technique popularized in recent years, extreme lateral interbody fusion (XLIF) has various advantages. In this study, we describe the application and efficacy of XLIF for the treatment of thoracic tuberculosis (TB), as this may be an emerging treatment option for thoracic TB in the future.Methods We present the case of a 75-year-old man who had suffered from chest and back pain for 1 month. Imaging studies showed destruction of the T12 and L1 vertebral bodies and the T12–L1 intervertebral disc, accompanied by formation of a paravertebral abscess. After 2 weeks of standard anti-TB treatment, the patient underwent debridement of the lesions, XLIF, and percutaneous pedicle screw fixation.Results The patient’s chest and back pain were significantly alleviated after the operation. The patient recovered well, and as of the most recent follow-up had no obvious limitation in thoracolumbar spine function.Conclusions XLIF combined with percutaneous pedicle screw fixation for the treatment of thoracic TB can allow for TB lesion debridement, discectomy, and interbody fusion under direct visualization, and can effectively improve patient prognosis.
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- 2024
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34. Visualization of GLUT1 Trafficking in Live Cancer Cells by the Use of a Dual-Fluorescence Reporter.
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Zhen-Yan Li, Yu-Ling Shi, Guo-Xiong Liang, Jie Yang, Song-Kuan Zhuang, Jie-Bin Lin, Abdelmoumin Ghodbane, Man-Seng Tam, Zu-Jian Liang, Zhen-Gang Zha, and Huan-Tian Zhang
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- 2020
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35. Pogocablanols A–G, a new class of sesquiterpenoids with an unprecedented bicyclic sesquiterpenoid skeleton from Pogostemon cablin (patchouli) and their activities.
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Zhou, Qin-Mei, Zhu, Huan, Ma, Chuan, Guo, Li, Peng, Cheng, and Xiong, Liang
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[Display omitted] Pogocablanols A–G (1 – 7), seven new compounds with an unprecedented sesquiterpenoid skeleton, were isolated from the aerial parts of Pogostemon cablin. This novel type of sesquiterpenoids, named pogocablane-type sesquiterpenoids, possesses a bicyclic nonisoprenoid system, including a five-membered carbocycle with a methyl group, a six-membered carbocycle with two methyl groups, and a methylene connecting the two carbocycles. Particularly, three isomers have an interesting 1-oxaspiro[4,4]nonane moiety. Their structures and absolute configurations were determined using extensive spectroscopic evidence, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Pogocablanols A–D (1 – 4) exhibited a concentration-dependent inhibitory effect on rat jejunum smooth muscle contraction induced by acetylcholine, with E max values varying from 48.87 ± 4.01% to 69.02 ± 7.54%. Preliminary structure–activity relationship analysis suggested that the oxaspirocycle and the pyran ring in pogocablanols are important structural features for the relaxing effects on jejunum smooth muscle. This study offered crucial support for more investigation and development of P. cablin by showing that these pogocablane-type sesquiterpenoids had the potential to be applied in pharmaceutical and functional food formulations. [ABSTRACT FROM AUTHOR]
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- 2023
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36. Sodium arsenite induces spatial learning and memory impairment associated with oxidative stress and activates the Nrf2/PPARγ pathway against oxidative injury in mice hippocampus
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Xiong, Liang, Huang, Jinyu, Gao, Ying, Gao, Yanfang, Wu, Chunmei, He, Shengfa, Zou, Lijun, Yang, Dongmei, Han, Yuhao, Yuan, Qiong, Zheng, Zuobing, and Hu, Gonghua
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Arsenic (As) is a ubiquitous environmental and industrial toxin with known correlates of oxidative stress and cognitive deficits in the brain. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcriptional factor that represents a central cellular antioxidant defense mechanism and transcribes many antioxidant genes. Peroxisome proliferator-activated receptor-gamma (PPARγ) is a well-known nuclear receptor to regulate lipid metabolism in many tissues, and it has been also associated with the control of oxidative stress, neuronal death, neurogenesis and differentiation. The role of Nrf2 and PPARγ in As-induced neurotoxicity is still debated. The present study was designed to investigate the neurobehavioral toxic effect of sub-chronic and middle-dose sodium arsenite exposure in mice hippocampus, as well as the response of Nrf2/PPARγ expression and influence on protein expression levels of their downstream antioxidant genes. Our results showed that mice treated with intraperitoneal injection of sodium arsenite (50 mg/kg body wt.) twice a week for 7 weeks resulted in increased generation of reactive oxygen species and impairment of spatial cognitive function. The present study also found a positive association between Nrf2/PPARγ expression in hippocampus of mice, and activation of antioxidant defenses by the evidently upregulated expression of their downstream genes, including superoxide dismutase, heme oxygenase-1 and glutathione peroxidase-3. Therefore, our findings were helpful for further understanding the role of Nrf2/PPARγ feedback loop in As-induced neurobehavioral toxicity.
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- 2021
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37. Establishment of intestinal organoid cultures modeling injury-associated epithelial regeneration
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Qu, Molong, Xiong, Liang, Lyu, Yulin, Zhang, Xiannian, Shen, Jie, Guan, Jingyang, Chai, Peiyuan, Lin, Zhongqing, Nie, Boyao, Li, Cheng, Xu, Jun, and Deng, Hongkui
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The capacity of 3D organoids to mimic physiological tissue organization and functionality has provided an invaluable tool to model development and disease in vitro. However, conventional organoid cultures primarily represent the homeostasis of self-organizing stem cells and their derivatives. Here, we established a novel intestinal organoid culture system composed of 8 components, mainly including VPA, EPZ6438, LDN193189, and R-Spondin 1 conditioned medium, which mimics the gut epithelium regeneration that produces hyperplastic crypts following injury; therefore, these organoids were designated hyperplastic intestinal organoids (Hyper-organoids). Single-cell RNA sequencing identified different regenerative stem cell populations in our Hyper-organoids that shared molecular features with in vivo injury-responsive Lgr5+stem cells or Clu+revival stem cells. Further analysis revealed that VPA and EPZ6438 were indispensable for epigenome reprogramming and regeneration in Hyper-organoids, which functioned through epigenetically regulating YAP signaling. Furthermore, VPA and EPZ6438 synergistically promoted regenerative response in gut upon damage in vivo. In summary, our results demonstrated a new in vitro organoid model to study epithelial regeneration, highlighting the importance of epigenetic reprogramming that pioneers tissue repair.
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- 2021
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38. Performance of 14Cr ODS-FeCrAl Cladding Tube for Accident Tolerant Fuel
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Li, Jing, Wu, Sa Jian, Wang, Yong Li, Xiong, Liang Yin, and Liu, Shi
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In the framework of Accident tolerant fuel (ATF) program, several types of claddings and pellets with enhanced accident tolerance have been developed for light water reactors. Oxide dispersion strengthened (ODS) FeCrAl alloys have been considered as a promising candidate for cladding materials due to their good mechanical strength, excellent structural stability and chemical durability at high temperature. The out-of-pile performance of 14Cr ODS-FeCrAl cladding tube fabricated by cold-rolling, such as microstructure, thermophysical property, mechanical property, and corrosion resistance, has been examined and discussed. The results confirm that iron-based ODS alloy is one of the promising candidates to be used as ATF cladding. It could also aid in the supplement of property database of ODS-FeCrAl for future use in nuclear cladding and structural applications in next generation nuclear systems.
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- 2021
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39. Regularization of mathematical model for chip flow angle catastrophe
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Zhang, Shao-Nan, Cheng, Dong-Dong, and Xiong, Liang-Shan
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The chip flow angle (CFA) catastrophe in double-edged cutting results in a significant reduction in the cutting force, which can benefit the applications. However, established potential functions (i.e., cutting power calculation functions) of mathematical models for the CFA catastrophe are presented in the form of transcendental functions with two control parameters and one state parameter, which are extremely complex. A method is proposed herein to realize the regularization of the potential functions and establish mathematical models in a standard form and with complete content for the CFA catastrophe. Using this method, the potential function of the CFA catastrophe is expanded into a k-order Taylor polynomial at each midpoint of Nend-to-end equally partitioned intervals of the state parameter using the Taylor function provided in MATLAB. The potential function after piecewise Taylor expansion is transformed into the same form as the potential function of the standard cusp catastrophe model by truncating the first five terms of the Taylor polynomial and eliminating the third-order term of the state parameter with elementary transformation. Hence, the regularization of potential function is realized. Subsequently, the regularization of equilibrium surface and bifurcation set can be realized based on the conclusions of the catastrophe theory. Regularization errors of the potential function, equilibrium surface, and bifurcation set are defined to evaluate the effectiveness of this regularization method. The problem of calculating regularization errors is regarded as an optimization problem. The “simulannealbnd” function provided in MATLAB is used to solve the problem. Applying the proposed method, the regularization of a mathematical model for the CFA catastrophe established by the predecessor is completed; a mathematical model (i.e., standard cusp catastrophe model) in a standard form and with complete content for the CFA catastrophe is established; and the corresponding regularization errors are analyzed. The regularization errors of the potential function, equilibrium surface, and bifurcation set curves are 5.485 5 × 10−4%, 0.320 6%, and 4.653 9%, respectively. Based on the equilibrium surface and the bifurcation set curves constructed using the regularized mathematical model for the CFA catastrophe, the mechanism of the CFA catastrophe and the specific approach to render the cutting system operable in a low-energy consumption state by controlling the historical change path of the control point are analyzed. This study will promote the rational use of the CFA catastrophe.
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- 2021
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40. Effect of postural changes on in vivo pelvic tilt and functional component anteversion in total hip arthroplasty patients with lumbar disc degenerations
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Klemt, Christian, Limmahakhun, Sakkadech, Bounajem, Georges, Xiong, Liang, Yeo, Ingwon, and Kwon, Young-Min
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AimsThe complex relationship between acetabular component position and spinopelvic mobility in patients following total hip arthroplasty (THA) renders it difficult to optimize acetabular component positioning. Mobility of the normal lumbar spine during postural changes results in alterations in pelvic tilt (PT) to maintain the sagittal balance in each posture and, as a consequence, markedly changes the functional component anteversion (FCA). This study aimed to investigate the in vivo association of lumbar degenerative disc disease (DDD) with the PT angle and with FCA during postural changes in THA patients.MethodsA total of 50 patients with unilateral THA underwent CT imaging for radiological evaluation of presence and severity of lumbar DDD. In all, 18 patients with lumbar DDD were compared to 32 patients without lumbar DDD. In vivo PT and FCA, and the magnitudes of changes (ΔPT; ΔFCA) during supine, standing, swing-phase, and stance-phase positions were measured using a validated dual fluoroscopic imaging system.ResultsPT, FCA, ΔPT, and ΔFCA were significantly correlated with the severity of lumbar DDD. Patients with severe lumbar DDD showed marked differences in PT with changes in posture; there was an anterior tilt (-16.6° vs -12.3°, p = 0.047) in the supine position, but a posterior tilt in an upright posture (1.0° vs -3.6°, p = 0.005). A significant decrease in ΔFCA during stand-to-swing (8.6° vs 12.8°, p = 0.038) and stand-to-stance (7.3° vs 10.6°,p = 0.042) was observed in the severe lumbar DDD group.ConclusionThere were marked differences in the relationship between PT and posture in patients with severe lumbar DDD compared with healthy controls. Clinical decision-making should consider the relationship between PT and FCA in order to reduce the risk of impingement at large ranges of motion in THA patients with lumbar DDD.Cite this article: Bone Joint J2020;102-B(11):1505–1510.
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- 2020
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41. Bismuth(III)-Doped NaYbF4:Tm3+Fluorides with Highly Efficient Upconversion Emission under Low Irradiance
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Huang, Xinyang, Xiong, Liang, Yu, Lin, Gao, Xiaohui, and Qiu, Xiaoqing
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Concentration quenching of upconversion (UC) luminescence (UCL) is a common phenomenon in rare-earth-doped materials that seriously restricts the concentration of the activator and sensitizer and withholds their UC emissions and quantum yields. In particular, it remains a tremendous challenge to develop one novel strategy based on the introduction of trivalent bismuth (Bi3+) ions to exceed the typical thulium (Tm3+) ion concentration and reach high-efficiency UC under low illumination. In this work, the Tm3+accommodation capacity can be increased from 2.0 to 8.0 mol % in NaYbF4:Tm3+materials with the assistance of Bi3+ions, which maintains strong UC emissions with large absolute UC quantum yields under low illumination. Specifically, the total upconversion quantum yield (UCQY) of the as-obtained Na(Tm0.08Yb0.60Bi0.32)F4(8Tm60Yb32Bi) sample can reach as high as 1.45% upon continuous-wave (CW) laser excitation at 40 W cm–2. Strikingly, the total UCQY still remains at a high level (0.41%) even though the CW power density decreases to 1.5 W cm–2. Moreover, the intrinsic mechanism of the breakthrough in the threshold of concentration quenching of UCL by Bi3+ions was also fully explored. These advances in enhancing UC emissions and UCQYs under a low pump power density offer exciting opportunities for important photonic applications.
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- 2020
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42. CAV1-CAVIN1-LC3B-mediated autophagy regulates high glucose-stimulated LDL transcytosis
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Bai, Xiangli, Yang, Xiaoyan, Jia, Xiong, Rong, Yueguang, Chen, Lulu, Zeng, Tianshu, Deng, Xiuling, Li, Wenjing, Wu, Guangjie, Wang, Ling, Li, Ye, Zhang, Jing, Xiong, Zhifan, Xiong, Liang, Wang, Yumei, Zhu, Lin, Zhao, Ying, and Jin, Si
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ABSTRACTDiabetes is a recognized high-risk factor for the development of atherosclerosis, in which macroautophagy/autophagy is emerging to play essential roles. The retention of low-density lipoprotein (LDL) particles in subendothelial space following transcytosis across the endothelium is the initial step of atherosclerosis. Here, we identified that high glucose could promote atherosclerosis by stimulating transcytosis of LDL. By inhibiting AMPK-MTOR-PIK3C3 pathway, high glucose suppresses the CAV-CAVIN-LC3B-mediated autophagic degradation of CAV1; therefore, more CAV1 is accumulated in the cytosol and utilized to form more caveolae in the cell membrane and facilitates the LDL transcytosis across endothelial cells. For a proof of concept, higher levels of lipids were accumulated in the subendothelial space of umbilical venous walls from pregnant women with gestational diabetes mellitus (GDM), compared to those of pregnant women without GDM. Our results reveal that high glucose stimulates LDL transcytosis by a novel CAV1-CAVIN1-LC3B signaling-mediated autophagic degradation pathway.Abbreviations3-MA: 3-methyladenine; ACTB: actin beta; AMPK: AMP-activated protein kinase; Bafi: bafilomycin A1; CAV1: caveolin-1; CAVIN1: caveolae associated protein 1; CSD: the CAV1 scaffolding domain; GDM: gestational diabetes mellitus; IMD: intramembrane domain; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule- associated protein 1 light chain 3; MFI: mean fluorescence intensity; MTOR: mechanistic target of rapamycin kinase; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; SQSTM1/p62: sequestosome 1.
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- 2020
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43. Fine characterization and target window optimization of high-quality shale gas reservoirs in the Weiyuan area, Sichuan Basin
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Wu, Hengzhi, Xiong, Liang, Ge, Zhongwei, Shi, Hongliang, Wang, Tong, and Fan, Li
- Abstract
Sinopec's Weiyuan Shale Gas Block is structurally located at the Baimazhen syncline held by the Weiyuan paleo-uplift and Ziliujing anticline in the Sichuan Basin. In this block, the Wufeng Fm of Upper Ordovician–Longmaxi Fm of Lower Silurian is an organic-rich dark shale deposit of deepwater shelf facies, whose litho-electric characteristics of geophysical logging are obviously different vertically and reservoir heterogeneity is strong. For providing a guidance for target window optimization and drilling trajectory tracking and adjustment of horizontal wells in the Weiyuan Shale Gas Block, parameter indexes were evaluated by refining the reservoir classification based on well logging subdivision, fine characterization of core laminae, high-precision geophysical prediction and genetic analysis of sedimentary microfacies. Furthermore, the “sweet spots” of shale gas reservoirs were predicted. Then, the target window was optimized and the trajectory of a horizontal well was designed. Finally, the effects of the target window of a horizontal well on shale gas productivity were evaluated. And the following research results were obtained. First, three types of laminae are developed in the high-quality shale reservoir at the bottom of Wufeng Fm–Long 1 Member, and they are vertically staggered and overlapped, which reflects the microscopic difference of sedimentary environment and reservoir quality. Second, shale gas reservoirs in this block can be divided into high-quality reservoirs, better reservoirs, general reservoirs and poor reservoirs. Third, the sublayer 2–31 at the bottom of Longmaxi Fm is biogenic sedimentary microfacies and it has the characteristics of “geological + engineering” sweet spot, e.g. high TOCcontents, high porosity, high brittleness, high gas content and low in-situ stress difference, so it is classified as a high-quality reservoir. Fourth, actual drilling results show that the location selection of the target window of a horizontal well has a significant impact on single-well shale gas productivity, and the penetration rate of a high-quality reservoir is the key geological factor to achieve high-yield shale gas. The research results provide support for the evaluation of shale gas productivity and lay a foundation for the commercial development of shale gas in the Weiyuan Shale Gas Block.
- Published
- 2019
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44. Three new 2,4′-epoxy-8,5′/8,3′-neolignans from Penthorum chinense.
- Author
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Liu, Fei, He, Ya-Cong, Zhu, Huan, Guo, Li, Peng, Cheng, and Xiong, Liang
- Abstract
Graphical abstract Highlights • Phytochemical study on Penthorum chinense yielded 3 new 2,4′-epoxy-8,5′/8,3′-neolignans. • 2,4′-Epoxy-8,3′-neolignan glycosides are reported for the first time. • 2,4′-Epoxy-8,5′/8,3′-neolignans were only found in P. chinense. Abstract Three new neolignans (1 − 3), including one 2,4′-epoxy-8,5′-neolignan and two 2,4′-epoxy-8,3′-neolignan glycosides, were isolated from the EtOAc-soluble portion of the water decoction of Penthorum chinense Pursh. Their structures and absolute configurations were elucidated by comprehensive analysis of spectroscopic data and electronic circular dichroism (ECD) calculations. Notably, the unusual 2,4′-epoxy-8,3′-neolignan glycosides are reported for the first time. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
45. Yttrium chloride induces ferroptosis in cardiomyocytes via iron accumulation and triggers cardiac lipid peroxidation and inflammation that cause heart adverse events in mice.
- Author
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Xiong, Liang, Huang, Jinyu, Wu, Chunmei, Yuan, Qiong, Wang, Sihui, Zhu, Liye, Li, Zilu, Sun, Ziyue, Fang, Yi, Li, Weisong, and Hu, Gonghua
- Subjects
IRON ,YTTRIUM ,GLUTATHIONE peroxidase ,PEROXIDATION ,HEART diseases ,HEART injuries - Abstract
The growing presence of yttrium (Y) in the environment raises concern regarding its safety and toxicity. However, limited toxicological data are available to determine cardiotoxicity of Y and its underlying mechanisms. In the present study, yttrium chloride (YCl 3) intervention with different doses was performed in male Kunming mice for the toxicological evaluation of Y in the heart. After 28 days of intragastric administration, 500 mg/kg·bw YCl 3 induces iron accumulation in cardiomyocytes, and triggers ferroptosis through the glutathione peroxidase 4 (GPX4)/glutathione (GSH)/system Xc
− axis via the inhibition of Nrf2 signaling pathway. This process led to cardiac lipid peroxidation and inflammatory response. Further RNA sequencing transcriptome analysis found that many genes involved in ferroptosis and lipid metabolism-related pathways were enriched. The ferroptosis induced by YCl 3 in cardiomyocytes ultimately caused cardiac injury and dysfunction in mice. Our findings assist in the elucidation of the potential subacute cardiotoxicity of Y3+ and its underlying mechanisms. • Yttrium chloride can induce iron accumulation in mice cardiomyocytes. • Yttrium chloride can trigger ferroptosis through GPX4/GSH/system Xc− axis via the inhibition of Nrf2 signaling pathway. • Yttrium chloride can cause subacute cardiac injury and dysfunction in mice. • Ferroptosis can be a viable target for protecting against YCl 3 -induced cardiotoxicity. [ABSTRACT FROM AUTHOR]- Published
- 2023
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- View/download PDF
46. Medicinal parts of mulberry (leaf, twig, root bark, and fruit) and compounds thereof are excellent traditional Chinese medicines and foods for diabetes mellitus.
- Author
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Liu, Chen-Hao, Liu, Fei, and Xiong, Liang
- Abstract
[Display omitted] • The hypoglycemic extracts and compounds in different medicinal parts of mulberry were systematically reviewed. • Mulberry has broad prospects in the prevention and treatment of diabetes mellitus. • The hypoglycemic compounds in mulberry are mainly flavonoids, polysaccharides, and alkaloids. • Their hypoglycemic effects involve the regulation of glucose metabolism, protection of pancreatic β-cells, and antioxidation. Diabetes mellitus (DM) is one of the main chronic diseases severely threatening human health, of which type 2 DM (T2DM) is the most common type. Traditional Chinese medicine has unique advantages in the treatment of T2DM. Mulberry (Morus alba L.) is a medicinal and edible plant that is well known for its rich nutrition and medicinal values. The medicinal parts of mulberry include leaf, twig, root bark, and fruit, all of which have remarkable hypoglycemic effects. In this paper, the extracts and compounds with hypoglycemic effects from four medicinal parts of mulberry are reviewed. It is found that the hypoglycemic compounds in mulberry are mainly flavonoids, polysaccharides, alkaloids, stilbenes, and Diels-Alder compounds. Their mechanisms of action are mainly related to the regulation of lipid profiles and glucose metabolism, protection of pancreatic β-cells, promotion of insulin secretion, antioxidation, inhibition of protein tyrosine phosphatase 1B and α-glycosidase activities. In addition, mulberry treatment could change intestinal microbiota of mice, which are associated with insulin resistance and diabetes. This review provides reference for further research and development of different medicinal parts of mulberry for the treatment of DM. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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47. Effect of lead, calcium, iron, zinc, copper and magnesium on anemia in children with BLLs ≥ 100 μg/L.
- Author
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Yu, Xiaoyu, Xiong, Liang, Zhao, Sha, Li, Zhengqiu, Xiang, Shiting, Cao, Yuhan, Zhou, Changci, Dong, Jie, and Qiu, Jun
- Subjects
LEAD ,COPPER ,IRON ,LEAD exposure ,TRACE elements ,ANEMIA - Abstract
Adverse effects of lead exposure on children's health have been demonstrated. While studies have examined the relationship between iron status and low-level lead exposure in children with blood lead levels (BLLs) < 100 μg/L, few have investigated the association between blood lead and other trace elements and anemia in children with BLLs ≥ 100 μg/L. This study aimed to assess the levels of lead, iron, copper, zinc, magnesium, and calcium in children aged 0–14 with BLLs≥ 100 μg/L between 2009 and 2021, and to examine the relationship between blood lead, trace elements and anemia. A total of 11,541 children with BLLs ≥ 100 μg/L were included in this study. Venous blood samples were collected to measure blood lead levels, hemoglobin levels, and trace element levels. According to the World Health Organization standard, outpatients with hemoglobin levels < 110 g / L were defined as having anemia. The study results found that high BLLs and blood calcium had a negative influence on Hb with odds ratios (95% confidence interval) of 1.411(1.208, 1.649) and 1.219(1.043, 1.424). High blood iron had a positive influence on Hb with odds ratios of 0.421(0.355, 0.499). The results suggest that the risk of anemia rose significantly with higher BLLs, blood copper, and blood calcium levels, and decreases considerably with higher blood iron levels. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. Treatment of diabetic foot with the transverse tibial bone transport guided by three-dimensional printing guide plates.
- Author
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Zhang, Yuan-Wei, Xiong, Liang-Yu, Gao, Wen-Cheng, and Deng, Liang
- Published
- 2020
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49. A unique case report of endobronchial cryptococcosis and review of the literature.
- Author
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Shuai, Shi-Yuan, Xiong, Liang, He, Xin-Liang, Yu, Fan, Xia, Qin, and Zhou, Qiong
- Abstract
Abstract Cryptococcosis is an infection caused by the yeast-like fungus Cryptococcus neoformans. Pulmonary cryptococcosis is typically identified as a single mass or as multiple nodules, while endobronchial lesions are quite rare. Here we report an uncommon case of pulmonary cryptococcosis presenting as endobronchial lesion in an immunocompetent patient. A 49-year-old male patient complained of intermittent cough with hemoptysis for two years. Computerized tomography of the chest showed a filling defect in the basal segment of the right lower lobe bronchus. A flexible bronchoscopic examination revealed a white smooth-surfaced polypoid lesion completely occluding the medial basal segment of the right lower lobe bronchus. The diagnosis was confirmed by bronchial biopsy under bronchoscopy, and the histopathologic findings showed the organisms were Cryptococcal neoforman s. The patient was treated with fluconazole at a dose of 400 mg daily. The endobronchial lesion was found rapidly diminished after 18 days of therapy, and disappeared after 6.5 months of therapy by repeated fiberoptic bronchoscopy. Then the patient continued fluconazole for another 2.5 months. During the total 16 months' follow-up visits, the patient repeated CT scanning for five times, the results of which were all normal. The patient's symptoms disappeared as well, and now he is still under follow-up. This case highlights the fact that pulmonary cryptococcosis can present as endobronchial lesions even in immunocompetent subjects, mimicking lung tumor. Pathological confirmation is important to establish the definite diagnosis. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
50. Polyoxygenated ergosteroids from the macrofungus Omphalia lapidescens and the structure-cytotoxicity relationship in a human gastric cancer cell line.
- Author
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Wang, Yue, Dai, Ou, Peng, Cheng, Su, Hai-Guo, Miao, Lu-Lin, Liu, Lu-Si, and Xiong, Liang
- Abstract
Seventeen polyoxygenated Δ 22 -ergosteroids ( 1 – 17 ), including two new compounds ( 1 and 15 ), were isolated from the ethyl acetate soluble fraction of a 95% ethanol extract of Omphalia lapidescens Schroet. According to the oxidation degree and the oxidation positions of A and B rings, the isolates could be divided into three subtypes: 3,5,6-trioxygenated Δ 7 -ergosteroids ( 1 – 9 ), 3,5,6,7-tetraoxygenated ergosteroids ( 10 – 14 ), and conjugated Δ 4,6,8 -3-one ergosteroids ( 15–17 ). The cytotoxic effects were studied using a human gastric cancer cell line, HGC-27, in vitro and the relationships between structure and cytotoxicity of the three subtypes were investigated. Among these subtypes, (3 β ,5α,6 β ,22 E )-6-methoxyergosta-7,22-diene-3,5-diol ( 5 ) exhibited the highest cytotoxicity, with an IC 50 value of 4.17 ± 0.48 μM. Furthermore, Hoechst fluorescence 33342 staining demonstrated that compound 5 could induce HGC-27 cell apoptosis significantly. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
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