32 results on '"Zong Q"'
Search Results
2. Energetic oxygen ion bursts in the distant magnetotail
- Author
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Zong, Q.-G., primary and Wilken, B., additional
- Published
- 1998
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3. Antibacterial and antifouling materials for urinary catheter coatings.
- Author
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Zhang Q, Zong Q, Feng X, Luo M, Sun W, and Zhai Y
- Abstract
Implantable medical devices have played a significant role in improving both medical care and patients' quality of life. Urinary Catheters (UCs) are commonly utilized as a substitute for bladder drainage and urine collection to prevent urinary retention in patients. However, bacterial colonization and biofilm formation on the catheter surface are prone to occur, leading to catheter-associated urinary tract infections (CAUTIs) and other complications. In recent years, UC coatings have garnered increasing attention. In this review, various antifouling and antibacterial materials for UC coatings are summarized and their impacts on bacterial activities are linked to potential mechanisms of action. Additionally, this review provides an in-depth understanding of the current advancements in UC coatings by presenting the advantages, limitations, notable achievements, and latest research findings. Finally, it anticipates the prospective design and development trajectories of UC coatings in this domain. This holds paramount significance in advancing medical device technology. STATEMENT OF SIGNIFICANCE: Combating catheter-associated urinary tract infections is a major healthcare challenge, and urinary catheter (UC) coatings are considered promising candidates to counter these infections. In this review, various antifouling and antibacterial materials for UCs are summarized, and their impacts on bacterial activities are linked to potential mechanisms of action. Additionally, the review provides an in-depth understanding of the current advancements in UC coatings by presenting the advantages, limitations, notable achievements, and latest research findings. This holds paramount significance in advancing medical device technology. This review not only contributes to the scientific research but also sparks interest among readerships and other researchers in the study of safer and more effective UC coatings for improved patient outcomes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2024
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4. Polystyrene nanoplastics enhance thrombosis through adsorption of plasma proteins.
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Sheng C, Wang G, Liu Z, Zheng Y, Zhao Z, Tang D, Li W, Li A, Zong Q, Zhou R, Hou X, Yao M, and Zhou Z
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- Adsorption, Animals, Molecular Dynamics Simulation, Plasminogen Activator Inhibitor 1 metabolism, Plasminogen Activator Inhibitor 1 chemistry, Microplastics toxicity, Microplastics chemistry, Humans, Polystyrenes chemistry, Polystyrenes toxicity, Blood Proteins chemistry, Blood Proteins metabolism, Thrombosis
- Abstract
Plastic products offer remarkable convenience for modern life. However, growing concerns are emerging regarding the potential health hazards posed by nanoplastics, which formed as plastics break down. Currently, the biological effects and mechanisms induced by nanoplastics are largely underexplored. In this study, we report that polystyrene nanoplastics can enter the bloodstream and enhance thrombus formation. Our findings show that polystyrene nanoplastics adsorb plasma proteins, particularly coagulation factor XII and plasminogen activator inhibitor-1, play a key role in this process, as demonstrated by proteomics, bioinformatic analyses, and molecular dynamics simulations. The adsorption of these proteins by nanoplastics is an essential factor in thrombosis enhancement. This newly uncovered pathway of protein adsorption leading to enhanced thrombosis provides new insights into the biological effects of nanoplastics, which may inform future safety and environmental risk assessment of plastics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
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- 2024
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5. STING modulates HBV-related acute-on-chronic liver failure by mediating autophagy and macrophage polarization.
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Zhang H, Liang T, Duan W, Liu F, Li L, Liu Q, Li J, Zong Q, Jin L, Wang Q, and Zhou Q
- Abstract
Background & Aims: HBV-related acute-on-chronic liver failure (HBV-ACLF) is a severe acute liver injury secondary to HBV-related chronic liver disease (with or without cirrhosis) and is characterized by a high short-term mortality rate. Presently, there is a paucity of experimental models that specifically focus on HBV-ACLF based on chronic hepatitis B. Therefore, this study aimed to establish an experimental mouse model of HBV-ACLF using chronic hepatitis B (CHB) as a basis and investigate the impact of STING activation on the disease., Methods: To simulate HBV-ACLF conditions, a model was constructed by combining chronic HBV replication (caudal vein high-pressure hydrodynamic injection of pAAV/HBV1.2 plasmid) and acute hepatic insult (intraperitoneal injection of Acetaminophen (APAP)). Then, model mice were administered either a STING agonist or STING inhibitor. Liver injury, STING pathway, autophagy flux, and macrophage polarization were assessed to elucidate the potential role of STING., Results: The mouse model developed chronic hepatitis B and acute liver injury, partially reflecting features of clinical HBV-ACLF based on CHB. STING activation, autophagy, and macrophage polarization were found to be involved in the disease process. During the early stage (6 h) of the STING agonist treatment group, the STING pathway was activated, autophagy flux was up-regulated, and liver inflammation and injury were alleviated. Contrastingly, at the late stage of STING agonist treatment (24 h, 48 h), macrophages were polarized to the M1 phenotype, exacerbating liver inflammatory infiltration and injury. However, treatment with a STING covalent inhibitor reversed these effects., Conclusions: Sting-induced autophagy exerts a protective effect on liver injury during the early stage. However, in later stages, STING may aggravate liver injury by shifting liver macrophage polarization to the M1 phenotype, thereby enhancing the inflammatory response., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier GmbH.)
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- 2024
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6. Activation of the cGAS-STING pathway by viral dsDNA leading to M1 polarization of macrophages mediates antiviral activity against hepatitis B virus.
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Zong Q, Zhang H, Liu F, Li J, Liu Q, Duan Z, Duan W, Ruan M, Zhang J, Liu Y, Zhou Q, and Wang Q
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- Animals, Mice, RAW 264.7 Cells, Hepatitis B immunology, Hepatitis B virology, Humans, Macrophage Activation immunology, Hepatocytes virology, Hepatocytes immunology, Hepatocytes metabolism, Interferon Regulatory Factor-3 metabolism, Hepatitis B virus physiology, Hepatitis B virus immunology, Nucleotidyltransferases metabolism, Macrophages immunology, Macrophages virology, Macrophages metabolism, DNA, Viral, Membrane Proteins metabolism, Signal Transduction
- Abstract
Background and Aims: Activation of the cGAS-STING pathway induces the production of type I interferons, initiating the antiviral immune response, which contributes to the clearance of pathogens. Previous studies have shown that STING agonists promote hepatitis B virus (HBV) clearance; however, few studies have investigated the effect of activating the cGAS-STING pathway in macrophages on HBV., Methods: The polarization status of HBV particle-stimulated RAW264.7 macrophages was analyzed. After stimulation with HBV particles, the analysis focused on determining whether the DNA sensors in RAW264.7 macrophages recognized the viral double-stranded DNA (dsDNA) and evaluating the activation of the cGAS-STING pathway. Coculture of mouse macrophages and hepatocytes harboring HBV was used to study the antiviral activity of HBV-stimulated RAW264.7 macrophages., Results: After stimulation with HBV particles, HBV relaxed circular DNA (rcDNA) was detected in RAW264.7 macrophages, and the protein expression of phospho-STING, phospho-TBK1, and phospho-IRF3 in the STING pathway was increased, as shown by Western blot analysis, which revealed that M1 polarization of macrophages was caused by increased expression of CD86. RT-PCR analyses revealed elevated expression of M1 macrophage polarization-associated cytokines such as TNFα, IL-1β, iNOS, and IFNα/β. In the coculture experiment, both HBsAg and HBeAg expression levels were significantly decreased in AML12-HBV1.3 cells cocultured with the supernatants of HBV-stimulated RAW264.7 macrophages., Conclusion: The results suggest that macrophages can endocytose HBV particles. Additionally, viral dsDNA can be recognized by DNA pattern recognition receptors, which in turn activate the cGAS-STING pathway, promoting the M1 polarization of macrophages, while no significant M2 polarization is observed. Macrophages stimulated with HBV particles exhibit enhanced antiviral activity against HBV., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)
- Published
- 2024
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7. Copper-gallate metal-organic framework encapsulated multifunctional konjac glucomannan microneedles patches for promoting wound healing.
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Zong Q, Peng X, Wu H, Ding Y, Ye X, Gao X, Sun W, and Zhai Y
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- Animals, Mice, Antioxidants pharmacology, Wound Healing, Anti-Bacterial Agents pharmacology, Copper pharmacology, Metal-Organic Frameworks pharmacology, Mannans
- Abstract
An ideal chronic wound dressing needs to have some properties, such as antibacterial, antioxidant, regulating macrophage polarization and promoting angiogenesis. This work presents a microneedle patch fabricated from oxidized konjac glucomannan (OKGM-MNs), in which Copper-gallate metal-organic framework (CuGA-MOF) is encapsulated for wound healing (denoted as CuGA-MOF@OKGM-MNs). CuGA-MOF is composed of Cu
2+ and gallic acid (GA), which are released through microneedles in the deep layer of the dermis. The released Cu2+ is able to act as an antibacterial agent and promote angiogenesis, while GA as a reactive oxygen species scavenger displays antioxidant activity. More attractively, the material OKGM used to prepare the microneedle patch is not only a drug carrier but also plays a role in promoting macrophage polarization M2 phenotype. In vitro experiments showed that CuGA-MOF@OKGM-MNs had good antibacterial and antioxidant properties. The therapeutic effect on wound healing has been confirmed in full-thickness skin wounds of diabetes mice models, which showed that the wound could be completely healed within 21 days under the treatment of CuGA-MOF@OKGM-MNs, and the healing effect was better than other groups. These indicated that the proposed CuGA-MOF@OKGM-MNs could be applicable in the treatment of clinical wound healing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)- Published
- 2024
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8. Temperature variability associated with respiratory disease hospitalisations, hospital stays and hospital expenses the warm temperate sub-humid monsoon climate.
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Zhai C, Bai L, Xu Y, Liu Y, Sun H, Gong X, Yu G, Zong Q, Hu W, Wang F, Cheng J, and Zou Y
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- Male, Child, Female, Humans, Temperature, Length of Stay, Hospitalization, Seasons, Hospitals, China, Hot Temperature, Environmental Exposure analysis, Respiratory Tract Diseases epidemiology
- Abstract
Objectives: The abrupt change of climate has led to an increasing trend of hospitalised patients in recent years. This study aimed to analyse the temperature variability (TV) associated with respiratory disease (RD) hospitalisations, hospital stays and hospital expenses., Study Design: The generalized linear model combined with distributed lag non-linear model was used to investigate the association between TV and RD hospitalisations., Methods: TV was determined by measuring the standard deviation of maximum and minimum temperatures for the current day and the previous 7 days. RD hospitalisations data were obtained from three major tertiary hospitals in Huaibei City, namely, the Huaibei People's Hospital, the Huaibei Hospital Of Traditional Chinese Medicine and the Huaibei Maternal and Child Health Care Hospital. First, using a time series decomposition model, the seasonality and long-term trend of hospitalisations, hospital stays and hospital expenses for RD were explored in this warm temperate sub-humid monsoon climate. Second, robust models were used to analyse the association between TV and RD hospitalisations, hospital stays and hospital expenses. In addition, this study stratified results by sex, age and season. Third, using the attributable fraction (AF) and attributable number (AN), hospitalisations, hospital stays and hospital expenses for RD attributed to TV were quantified., Results: Overall, 0.013% of hospitalisations were attributed to TV
0-1 (i.e. TV at the current day and previous 1 day), corresponding to 220 cases, 1603 days of hospital stays and 1,308,000 RMB of hospital expenses. Females were more susceptible to TV than males, and the risk increased with longer exposure (the highest risk was seen at TV0-7 [i.e. TV at the current day and previous 7 days] exposure). Higher AF and AN were observed at ages 0-5 years and ≥65 years. In addition, it was also found that TV was more strongly linked to RD in the cool season. The hot season was positively associated with hospital stays and hospital expenses at TV0-3 to TV0-7 exposure., Conclusions: Exposure to TV increased the risk of hospitalisations, longer hospital stays and higher hospital expenses for RD. The findings suggested that more attention should be paid to unstable weather conditions in the future to protect the health of vulnerable populations., (Copyright © 2023 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.)- Published
- 2023
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9. Multifunctional hydrogel wound dressing with rapid on-demand degradation property based on aliphatic polycarbonate and chitosan.
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Zong Q, Peng X, Ding Y, Wu H, Lu C, Ye J, Sun W, Zhang J, and Zhai Y
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- Humans, Hydrogels pharmacology, Antioxidants pharmacology, Anti-Bacterial Agents pharmacology, Bandages, Carbonates, Chitosan
- Abstract
The multifunctional hydrogel dressings are effective strategy to treat chronic wounds of diabetes. In addition, the ability of selective degradation on demand to change dressings could provide better patient compliance. Here, an injectable, self-healing hydrogel with rapid degradability on-demand is designed to promote the healing of diabetes wounds. The block copolymer formed by aldehyde modified aliphatic cyclic carbonate monomer with polyethylene glycol (MBP) and chitosan (CS) were crosslinked through the Schiff base bond to obtain a hydrogel with excellent injectability and self-healing ability. Due to the presence of carbonate bonds in MBP, it showed the rapid on-demand degradation characteristics triggered by N-acetylcysteine (NAC). At the same time, gallic acid (GA) was loaded into the hydrogel, giving the hydrogel dressing antioxidant. In vivo and in vitro experiments showed that the hydrogel wound dressing possesses good natures, such as antibacterial, antioxidant, and friendly cell compatibility, which could promote wound healing. Overall, the multifunctional hydrogel wound dressings with rapid on-demand degradation characteristics are more practical for clinical applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)
- Published
- 2023
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10. The global burden and trends of four major types of heart disease, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019.
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Yu G, Gong X, Xu Y, Sun H, Liu Y, Zhai C, Hu W, Zong Q, Hu D, Yan Z, Wang Y, Wang L, Zhang T, Wang F, and Zou Y
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- Humans, Young Adult, Adult, Global Burden of Disease, Quality-Adjusted Life Years, Global Health, Myocardial Ischemia epidemiology, Rheumatic Heart Disease epidemiology
- Abstract
Objectives: The global burden of heart disease is severe and increasing in the coming years. This study aims to analyze the global burden of heart disease., Study Design: Rheumatic heart disease (RHD), ischemic heart disease (IHD), hypertensive heart disease (HHD), and non-rheumatic valvular heart disease (NRVHD) were selected and analyzed from the Global Burden of Disease Study 2019., Methods: The prevalence, deaths, disability-adjusted life years and their corresponding age-standardized rates were obtained from the Global Burden of Disease Study 2019. In addition, estimated annual percentage change was calculated to better assess epidemiological trends. In addition, we performed an age-period-cohort analysis using the Nordpred package in R program to predict death trends over the next 20 years., Results: Globally, the prevalence of four heart diseases (RHD, IHD, HHD, and NRVHD) increased by 70.5%, 103.5%, 137.9%, and 110.0% compared with 1990, respectively. The deaths cases of RHD decreased by 15.6%, whereas IHD, HHD, and NRVHD increased by 60.4%, 76.6%, and 110.6%. Compared with absolute values, their corresponding age-standardized rates only showed a slight increase trend or even decreased in some areas with high sociodemographic index. In the next 20 years, the absolute values of deaths will continue to increase, whereas their age-standardized rates of deaths will flatten out., Conclusions: Globally, the absolute values of heart disease have increased over the past 30 years and will continue to increase over the next 20 years. Targeted prevention and control strategies and measures need to be developed and improved to reduce this burden., (Copyright © 2023 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2023
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11. Global, regional, and national deaths, disability-adjusted life years, years lived with disability, and years of life lost for the global disease burden attributable to second-hand smoke, 1990-2019: A systematic analysis for the Global Burden of Disease Study.
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Zhai C, Hu D, Yu G, Hu W, Zong Q, Yan Z, Wang Y, Wang L, Zhang T, Sun H, Cai L, Cui L, Wang F, and Zou Y
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- Humans, Disability-Adjusted Life Years, Quality-Adjusted Life Years, Global Burden of Disease, Life Expectancy, Tobacco Smoke Pollution adverse effects
- Abstract
Background: Smoke-free policies have led to a decline in smoking prevalence. Nevertheless, as the global population grows, more non-smokers are exposed to second-hand smoke (SHS) hazards. Mitigating SHS hazards requires a systematic analysis of the global disease burden attributable to SHS., Methods: Data on SHS was extracted from the Global Burden of Disease Study 2019. First, we measured the disease burden of SHS by the number of cases and age-standardized rates of deaths, disability-adjusted life years (DALYs), years lived with disability (YLDs), and years of life lost (YLLs) from 1990 to 2019. Second, trends in the disease burden of SHS in different periods were estimated based on the annual percentage change (APC) by joinpoint regression analysis. Finally, using histogram plots, world maps, Pearson correlation analysis, and population attributable fraction (PAF), we conducted a stratified analysis of SHS exposure by sex, age, geographic location, sociodemographic index (SDI) level, and disease., Results: The number of deaths caused by SHS remained stable between 1990 and 2019, and the number of YLDs more than doubled in three decades. In contrast, the number of DALYs and YLLs caused by SHS decreased. The declining trend in deaths (APC = -1.42 % [95 % UI -1.79 %, -1.05 %]), DALYs (APC = -1.91 % [95 % UI -2.15 %, -1.67 %]), and YLLs (APC = -1.28 % [95 % UI -1.93 %, -0.64 %]) had slowed down in recent years, while SHS-related YLDs were still increasing (APC = 1.84 % [95 % UI 0.74 %, 2.96 %]). From 2010 to 2019, we found that SHS exposure increased the risk of tracheal, bronchus, and lung cancer (PAF increased by 11.75 %), breast cancer (PAF increased by 5.36 %), diabetes mellitus (PAF increased by 8.24 %), and ischemic heart disease (PAF increased by 4.46 %). In addition, the disease burden caused by SHS was highest in middle SDI and low-middle SDI countries., Conclusion: The global disease burden attributable to SHS is still severe, and policymakers need to implement more effective measures to reduce the harm of SHS., Competing Interests: Declaration of competing interest The authors have declared no conflict of interests., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2023
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12. Self-amplified chain-shattering cinnamaldehyde-based poly(thioacetal) boosts cancer chemo-immunotherapy.
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Zong Q, Li J, Xiao X, Du X, and Yuan Y
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- Humans, Doxorubicin pharmacology, Doxorubicin therapeutic use, Polymers therapeutic use, Reactive Oxygen Species metabolism, Cell Line, Tumor, Tumor Microenvironment, Stimuli Responsive Polymers, Nanoparticles, Neoplasms drug therapy
- Abstract
The selective activation of stimuli-responsive polymers in the tumor microenvironment is a great concern to achieve intelligent cancer therapy, but most of them show inadequate response due to insufficient endogenous triggering agents. Herein, we rationally designed a reactive oxygen species (ROS)-responsive cinnamaldehyde (CA)-based poly(thioacetal), consisting of ROS-responsive thioacetal (TA) and ROS-generating agent CA, with self-amplified chain-shattering polymer degradation. The mechanism of self-amplified chain-shattering is that endogenous ROS as a triggering agent facilitates chain cleavage of TA with the release of CA, which in turn produces more ROS through mitochondrial dysfunction, resulting in an exponential polymer degradation cascade. The polymer can be further modified with anticancer drug doxorubicin (DOX) for cooperative amplification of oxidative stress and immunogenic cell death (ICD) of tumor cells, thereby boosting the effect of chemo-immunotherapy. The self-amplified chain-shattering polymer designed in this work holds great promise in developing stimuli-responsive polymers for efficient drug delivery. STATEMENT OF SIGNIFICANCE: This study presented an approach to utilize self-amplified chain-shattering cinnamaldehyde-based poly (thioacetal) as a drug delivery system to restrain tumor growth and boost chemo-immunotherapy. The endogenous ROS as a triggering agent initiates the chain cleavage with the release of CA, which in turn produces ROS through mitochondria dysfunction, resulting in an exponential polymer degradation cascade and rapid drug release., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2022 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2022
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13. Lactoferrin Attenuates Intestinal Barrier Dysfunction and Inflammation by Modulating the MAPK Pathway and Gut Microbes in Mice.
- Author
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Hu P, Zong Q, Zhao Y, Gu H, Liu Y, Gu F, Liu HY, Ahmed AA, Bao W, and Cai D
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- Animals, Male, Mice, Inflammation chemically induced, Lactoferrin pharmacology, Occludin genetics, RNA, Messenger, Gastrointestinal Microbiome, Intestinal Diseases, Trichothecenes toxicity, MAP Kinase Signaling System
- Abstract
Background: Deoxynivalenol (DON) is a major mycotoxin present in staple foods (particularly in cereal products) that induces intestinal inflammation and disrupts intestinal integrity. Lactoferrin (LF) is a multifunctional protein that contributes to maintaining intestinal homeostasis and improving host health. However, the protective effects of LF on DON-induced intestinal dysfunction remain unclear., Objectives: This study aimed to investigate the effects of LF on DON-induced intestinal dysfunction in mice, and its underlying protective mechanism., Methods: Male BALB/c mice (5 wk old) with similar body weights were divided into 4 groups (n = 6/group) and treated as follows for 5 wk: Veh [peroral vehicle daily, commercial (C) diet]; LF (peroral 10 mg LF/d, C diet); DON (Veh, C diet containing 12 mg DON/kg); and LF + DON (peroral 10 mg LF/d, DON diet). Intestinal morphology, tight junction proteins, cytokines, and microbial community were determined. Data were analyzed by 2-factor ANOVA or Kruskal-Wallis test., Results: The DON group exhibited lower final body weight (-12%), jejunal villus height (VH; -41%), and jejunal occludin expression (-36%), and higher plasma IL-1β concentration (+85%) and jejunal Il1b mRNA expression (+98%) compared with the Veh group (P < 0.05). In contrast, final body weight (+19%), jejunal VH (+49%), jejunal occludin (+53%), and intelectin 1 protein expression (+159%) were greater in LF + DON compared with DON (P < 0.05). Additionally, jejunal Il1b mRNA expression (-31%) and phosphorylation of p38 and extracellular signal regulated kinase 1/2 (-40% and - 38%) were lower in LF + DON compared with DON (P < 0.05). Furthermore, the relative abundance of Clostridium XIVa (+181%) and colonic butyrate concentration (+53%) were greater in LF + DON compared with DON (P < 0.05)., Conclusions: Our study highlights a promising antimycotoxin approach using LF to alleviate DON-induced intestinal dysfunction by modulating the mitogen-activated protein kinase pathway and gut microbial community in mice., (Copyright © 2022 American Society for Nutrition.)
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- 2022
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14. Investigating and modeling the toxicity of arsenate on wheat root elongation: Assessing the effects of pH, sulfate and phosphate.
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Li M, Song N, Song X, Liu J, Su B, Chen X, Guo X, Li M, and Zong Q
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- Humans, Hydrogen-Ion Concentration, Ligands, Phosphates pharmacology, Plant Roots, Sulfates toxicity, Arsenates toxicity, Triticum
- Abstract
Excessive arsenic in soil and groundwater will not only seriously affect the growth of plants, but also endanger human health through the food chain. However, there are few studies on the effects of metalloid speciation and anion competition on the toxicity of arsenate [As(Ⅴ)]. To investigate the effects of accompanying anions and pH on the toxicity of As(Ⅴ) on wheat root elongation, wheat roots were exposed to the concentrations of As(Ⅴ) in the solution ranged from 0 to 500 mM and different levels of pH (4.5-8.0) and different accompanying anions (H
2 PO4 - , SO4 2- , NO3 - and Cl- ) for five days. The root length of wheat was measured and the biotic ligand model (BLM) was developed to predict the potential toxicity of As(V) speciation to wheat roots. The results illustrated that EC50 of total As(V) (EC50{As(Ⅴ)T }) values increased from 6.88 to 33.9 μM with increasing pH values from 4.5 to 8.0, suggesting that increasing pH alleviated As(Ⅴ) toxicity. The EC50{AsO4 3- } and EC50{HAsO4 2- } values increased from 0.001 to 4342 μM and from 0.0214 to 27.4 μM, respectively, while the EC50{H2 AsO4 - } and EC50{H3 AsO4 } values sharply decreased from 6.62 to 2.68 μM and from 41.8 μM to 5.34 nm, respectively, when pH increased from 4.5 to 8.0. The toxicity of As(Ⅴ) decreased as the H2 PO4 - and SO4 2- activities increased but not when the activities of NO3 - and Cl- increased, indicating that SO4 2- and H2 PO4 - showed competitive effects with As(Ⅴ) on the binding sites. Based on BLM theory, the stability constants were obtained: [Formula: see text] = 3.70; [Formula: see text] = 4.08; [Formula: see text] = 4.77; [Formula: see text] = 6.50; [Formula: see text] = 2.09 and [Formula: see text] = 1.86, with fAsBL 50% = 0.30 and β = 1.73. Results implied that BLM performed well in As(Ⅴ) toxicity prediction when coupling toxic species AsO4 3- , HAsO4 2- , H2 AsO4 - , and H3 AsO4 , and the competition of SO4 2- and H2 PO4 - for binding sites. The current study provides a useful tool to accurately predict As(V) toxicity to wheat roots., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2022
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15. Sequential enzyme-activated macrotheranostic probe for selective tumor mitochondria targeting.
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Ma D, Zong Q, Du Y, Yu F, Xiao X, Sun R, Guo Y, Wei X, and Yuan Y
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- Cell Line, Tumor, Fluorescence, Fluorescent Dyes, Humans, Mitochondria, Reactive Oxygen Species, Neoplasms diagnostic imaging, Neoplasms drug therapy
- Abstract
Subcellular organelle targeted imaging and therapy are of enormous interest in cancer theranostics. However, the lack of tumor-selective organelle targeting has compromised their efficacy and safety. In this work, we found that the near-infrared (NIR) fluorophore hemicyanine (CyNH
2 ) can selectively target mitochondria with strong cytotoxicity through decreasing the mitochondrial membrane potential and increasing the intracellular reactive oxygen species (ROS) levels. A macrotheranostic probe (denoted as PLCy) based on conjugating CyNH2 with an acetylated lysine group was developed with masked fluorescence and cytotoxicity, which could both be unmasked through sequential activation by cancer cells overexpressing histone deacetylases (HDACs) and cathepsin L (CTSL) enzymes for selective cancer cell mitochondria-targeted imaging and therapy. In vitro and in vivo studies confirmed that the specific fluorescence turn-on and toxicity were restored in cancer cells and efficiently inhibited tumor growth. This macrotheranostic probe with sequential enzyme activation and mitochondrial targeting is expected to have promising applications in imaging-guided cancer therapy with high specificity and efficiency. STATEMENT OF SIGNIFICANCE: To improve the targeting efficiency and enhance the anti-cancer activities of macrotheranostic probe. We designed macrotheranostic probe PLCy that can be activated via sequential enzymes for selective tumor mitochondria targeting. More importantly, the activated CyNH2 can decrease the mitochondrial membrane potential and elevate the reactive oxygen species level in cancer cells without light irradiation, which can further induce apoptosis of tumor cells for chemotherapy. Therefore, the use of sequential enzyme activation and mitochondria targeting strategies in the context of enzymatic activation may provide a general strategy for organelle-targeted imaging and therapy with high specificity and efficiency., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)- Published
- 2021
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16. Development of gold nanorods for cancer treatment.
- Author
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Zong Q, Dong N, Yang X, Ling G, and Zhang P
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- Animals, Antineoplastic Agents chemistry, Antineoplastic Agents radiation effects, Cell Line, Tumor, Doxorubicin therapeutic use, Drug Carriers chemistry, Drug Carriers radiation effects, Drug Carriers therapeutic use, Drug Therapy, Gold chemistry, Gold radiation effects, Humans, Metal Nanoparticles chemistry, Metal Nanoparticles radiation effects, Nanotubes radiation effects, Photochemotherapy, Photosensitizing Agents chemistry, Photosensitizing Agents radiation effects, Photosensitizing Agents therapeutic use, Photothermal Therapy, Antineoplastic Agents therapeutic use, Metal Nanoparticles therapeutic use, Nanotubes chemistry, Neoplasms drug therapy
- Abstract
There has been growing interest in the application of gold nanorods (GNRs) to tumor therapy due to the unique properties they possess. In the past, GNRs were not used in clinical treatments as they lacked stability in vivo and were characterized by potential toxicity. Despite these issues, the significant potential for utilizing GNRs to conduct safe and effective treatments for tumors cannot be ignored. Therefore, it remains crucial to thoroughly investigate the mechanisms behind the toxicity of GNRs in order to provide the means of overcoming obstacles to its full application in the future. This review presents the toxic effects of GNRs, the factors affecting toxicity and the methods to improve biocompatibility, all of which are presently being studied. Finally, we conclude by briefly discussing the current research status of GNRs and provide additional perspective on the challenges involved along with the course of development for GNRs in the future., (Copyright © 2021. Published by Elsevier Inc.)
- Published
- 2021
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17. Efficacy of ribavirin and interferon-α therapy for hospitalized patients with COVID-19: A multicenter, retrospective cohort study.
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Li H, Xiong N, Li C, Gong Y, Liu L, Yang H, Tan X, Jiang N, Zong Q, Wang J, Lu Z, and Yin X
- Subjects
- Adult, Aged, COVID-19 mortality, Drug Therapy, Combination, Female, Humans, Male, Middle Aged, Retrospective Studies, Antiviral Agents administration & dosage, Interferon-alpha administration & dosage, Ribavirin administration & dosage, SARS-CoV-2, COVID-19 Drug Treatment
- Abstract
Objective: To assess the efficacy and safety of ribavirin and interferon-α (RBV/IFN-α) therapy in COVID-19 patients., Methods: A multicenter, retrospective cohort study of COVID-19 patients admitted to 4 hospitals in Hubei Province, China, from 31 December 2019 to 31 March 2020. Patients were divided into 2 groups according to their exposure to RBV/IFN-α therapy within 48 h of admission. Mixed-effect Cox model and Logistic regression were used to explore the association between early treatments of RBV/IFN-α and primary outcomes., Results: Of 2037 patients included, 1281 received RBV/IFN-α (RBV, IFN-α or RBV combined with IFN-α) treatments and 756 received none of these treatments. In a mixed effect model, RBV/IFN-α therapy was not associated with progression from non-severe into severe type (adjusted hazard ratio (aHR) = 1.09, 95% CI: 0.88-1.36) or with reduction in 30-day mortality (aHR = 0.89, 95% CI: 0.61-1.30). However, it was associated with a higher probability of hospital stay >15 days (adjusted odds ratio (aOR) = 2.11, 95% CI: 1.68-2.64) compared with no RBV/IFN-α therapy. The propensity score-matched cohort and subgroup analysis displayed similar results., Conclusion: RBV/IFN-α therapy was not observed to improve clinical outcomes in COVID-19 patients suggesting that RBV/IFN-α therapy should be avoided in COVID-19 treatment., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2021
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18. Impact of variations in vegetation on surface air temperature change over the Chinese Loess Plateau.
- Author
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Jin K, Wang F, Zong Q, Qin P, and Liu C
- Abstract
Studying the drivers and combating the effects of climate change is more urgent than ever, particularly in regions with limited water and sensitive ecosystems. This study evaluated the effect of vegetation variation on surface air temperature (SAT) change in the Chinese Loess Plateau over 1982-2015 based on the 'observation minus reanalysis' (OMR) method. Observed temperature, ERA-Interim reanalysis temperature, and Global Inventory Modeling and Mapping Studies normalized difference vegetation index (NDVI) 3rd generation were used to analyze the relationship between OMR temperature (representing vegetation impact on SAT) and NDVI. Results showed that the Loess Plateau, especially its central-east areas, has undergone a rapid increase in NDVI and rapid decrease in OMR temperature during 1982-2015. This implies a strong cooling effect of vegetation restoration on SAT change. The mean annual NDVI (M
NDVI ) and NDVI trend (SlopeNDVI ) were negatively correlated with OMR temperature trend (SlopeOMR ) on the Loess Plateau (P < 0.001). However, the relationships between MNDVI (SlopeNDVI ) and SlopeOMR varied among the arid, semi-arid, and semi-humid regions. As a result, the impacts of restoration of vegetation condition on SAT change during 1982-2015 were estimated to be 0.04, -0.01, and -0.07 °C decade-1 in the arid, semi-arid, and semi-humid regions, respectively. For the entire Loess Plateau, the restoration of its vegetation condition led to a cooling effect of -0.02 °C decade-1 during 1982-2015 and a cooling effect of -0.05 °C in the period following the implementation of the Grain for Green Project (GGP). Moreover, among the three major land use types of the Loess Plateau (i.e., grassland, farmland, and forest), vegetation restoration of forest demonstrated the most obvious cooling effect (-0.06 °C decade-1 during 1982-2015). These results are the first quantitative estimation of the impact of vegetation variation on SAT across the entire Loess Plateau, and demonstrate the ecological effect of afforestation efforts in the southeastern areas in terms of climate warming alleviation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2020
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19. Reconstruction of abdominal wall with scaffolds of electrospun poly (l-lactide-co caprolactone) and porcine fibrinogen: An experimental study in the canine.
- Author
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Li S, Su L, Li X, Yang L, Yang M, Zong H, Zong Q, Tang J, and He H
- Subjects
- Animals, Cell Death, Cell Proliferation, Collagen metabolism, Disease Models, Animal, Dogs, Endothelial Cells drug effects, Female, Fibrinogen pharmacology, Implants, Experimental, Male, Muscle Fibers, Skeletal metabolism, Myoblasts metabolism, Polypropylenes chemistry, Porosity, Swine, Abdominal Wall surgery, Fibrinogen therapeutic use, Polylactic Acid-Polyglycolic Acid Copolymer chemistry, Plastic Surgery Procedures, Tissue Engineering, Tissue Scaffolds chemistry
- Abstract
Background: The use of permanent synthetic materials for abdominal wall repair is currently the method of choice. However, they are not ideal as short-term and long-term complications have been reported for these materials including chronic groin pain (pain that lasted longer than 3 months), which occurred in 10-12% of patients, and host immunological responses to foreign body grafts. In the present randomized paired study we compared an electrospun composite scaffold composed of poly (l-lactide-co-caprolactone) [PLCL] blended with porcine fibrinogen (F-Fg) (PLCL/F-Fg), with a polypropylene mesh (PPM) as the control in a canine abdominal wall defect model (in 36 Beagle dogs)., Results: A blend ratio of 4:1 PLCL: F-Fg1 scaffold possessed optimal physical characteristics including shrinkage rate, mechanical strength, porosity and super-hydrophilic properties. Macroscopic, histological and biomechanical evaluations were performed over a period of 36 weeks and the results indicated that the resorbable PLCL/F-Fg1 electrospinning scaffold could effectively induce and augment abdominal skeletal muscle regeneration. The degradation rate of the PLCL/F-Fg1 scaffold and the rate of new tissue growth reached a balance and the biomechanical strength returned to baseline within 2 weeks of implantation. The immunohistological data demonstrated the presence of regenerated skeletal muscle tissue for PLCL/F-Fg1 scaffolds, whereas the PPM exhibited dense fibrous encapsulation along the perimeter of the mesh., Conclusions: The data provides the foundation for future clinical applications of PLCL/F-Fg1 composite scaffolds for reconstructive surgery of abdominal wall defects., Competing Interests: Declaration of competing interest LS, LY, MY, HHZ, QHZ, and HBH received financial support in the form of salaries from Shanghai Pine & Power Biotech Co., Ltd. (Shanghai, China). SJL, XXL and JXT have no competing interests to declare., (Copyright © 2020. Published by Elsevier B.V.)
- Published
- 2020
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20. Perylenequinone-based "turn on" fluorescent probe for hydrogen sulfide with high sensitivity in living cells.
- Author
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Chen JP, Duan YM, Zheng WJ, Zhang Q, Zong Q, Chen S, Wang KP, and Hu ZQ
- Subjects
- Fluorescence, Fluorescent Dyes chemical synthesis, HeLa Cells, Humans, Limit of Detection, Microscopy, Confocal, Optical Imaging, Perylene chemical synthesis, Perylene chemistry, Quinones chemical synthesis, Spectrometry, Fluorescence, Fluorescent Dyes chemistry, Hydrogen Sulfide analysis, Perylene analogs & derivatives, Quinones chemistry
- Abstract
Hydrogen sulfide (H
2 S) is a kind of gaseous signal molecule in many physiological processes. In order to detect H2 S, a novel "turn on" fluorescent probe 6,12-dihydroxyperylene-1,7-dione (DPD) was designed and synthesized. The probe DPD is fluorescence silence, while the addition of H2 S induces an obvious green fluorescence with an obvious color change from dark blue to yellow-green. The probe shows excellent selectivity, fast response (2.5min) and linear curve (0-90μM) in wide effective pH range (4-10). Competition experiments are also revealed in corresponding studies and the detection limit is 3.6μM. The response mechanism is proved to be the reduction of the probe by H2 S, which is confirmed by1 H NMR. Furthermore, through the fluorescence turn-on signal toward H2 S in Hela cells, probe DPD was successfully applied to monitor H2 S in living Hela cells., (Copyright © 2019. Published by Elsevier B.V.)- Published
- 2019
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21. Tracking control of an underactuated ship by modified dynamic inversion.
- Author
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Ye L and Zong Q
- Abstract
The tracking control problem of an underactuated ship is investigated. We intend to use the underactuated ship as an example to extend the traditional dynamic inversion control method to underactuated systems. The difficulty lies in the fact that the system has no relative degree, which prevents the application of standard dynamic inversion. Three modified dynamic inversion methods are proposed that are applicable to this system. The first is the well-known dynamic extension-based dynamic inversion (DEDI), which treats an input as a state and takes dynamic extension to achieve a relative degree. The second is virtual input-based dynamic inversion (VIDI), which treats a state as a virtual input to achieve a relative degree. The third is output redefinition-based dynamic inversion (ORDI), which selects a particular variable as a new output to achieve a relative degree. The three methods are generalizations of dynamic inversion control and remove some of its inherent limitations, making it applicable to a wide variety of underactuated systems. The effectiveness of the proposed methods is verified by numerical simulations., (Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2018
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22. A positron emission tomography image-guidable unimolecular micelle nanoplatform for cancer theranostic applications.
- Author
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Yang J, Lu W, Xiao J, Zong Q, Xu H, Yin Y, Hong H, and Xu W
- Subjects
- Animals, Cell Line, Tumor, Copper Radioisotopes chemistry, Doxorubicin pharmacology, Doxorubicin therapeutic use, Drug Delivery Systems, Drug Liberation, Humans, Mice, Molecular Weight, Nanoparticles, Neoplasms pathology, Particle Size, Peptides chemistry, Polyamines chemical synthesis, Polyamines chemistry, Proton Magnetic Resonance Spectroscopy, Static Electricity, Micelles, Neoplasms therapy, Positron-Emission Tomography, Theranostic Nanomedicine
- Abstract
Unimolecular micelles based on hyperbranched polyamidoamine (PAMAM) dendrimer were synthesized as both a cargo delivery vector and an imaging agent for triple-negative breast tumors, and the chemical synthesis procedures are detailed in this study. With the chemical conjugation of a peptide (F3, against cellular nucleolin) to increase its cellular internalization, these micelles can accumulate potently and specifically in breast cancer cells (e.g., MDA-MB-231). The size and morphology of these PAMAM-based micelles have been measured by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The hydrazone bond (responsive to pH alteration) between the loaded doxorubicin (DOX, as a model drug here) and PAMAM micelles enables cargo release following pH changes. Flow cytometry and confocal fluorescence microscopy revealed that PAMAM micelles with F3 attachment (PAMAM-DOX-F3) had stronger internalization into MDA-MB-231 cells (nucleolin-positive) than PAMAM micelles without F3 conjugation (PAMAM-DOX), whereas both of them have minimal interactions with L929 fibroblasts (nucleolin-negative). The positron-emitting isotope
64 Cu was added into PAMAM micelles by chelation to track their pharmacokinetic behavior (organ distribution profile) in vivo by positron emission tomography (PET) imaging. Serial PET imaging demonstrated that the accumulation of64 Cu-PAMAM-DOX-F3 in MDA-MB-231 tumors was fast, potent, and persistent (tumor uptake: 6.1 ± 1.2% injection dose per gram [%ID/g] at 24 h p.i.), significantly higher than that of64 Cu-PAMAM-DOX (2.5 ± 0.4%ID/g at the same time). Their distribution profiles in other organs/tissues were quite similar, with a relatively short circulation time. In addition, ex vivo fluorescence imaging confirmed that DOX can be delivered efficiently by these PAMAM micelles to MDA-MB-231 tumors. Deducing from these data, we believe that PAMAM-based micelles can be useful for selective combinational treatment of cancer., Statement of Significance: Micelles are a very useful biomaterial for theranostic purposes, and one of the major hurdles for micelles (particularly those from self-assembling) is their relatively low stability, especially when administered in vivo. In this study, we have attempted to overcome this limitation by designing unimolecular micelles (based on the concept of "one micelle is composed of one macromolecule") from polyamidoamine (PAMAM) dendrimers, in which the drug cargos (e.g., doxorubicin) are chemically attached to PAMAM through a hydrazone bond; hence, they can be used as a tumor-selective diagnostic/therapeutic platform. These unimolecular micelles possess superior stability compared to conventional micelles and can undertake stimulus (pH)-responsive cargo release for more "targeted" cancer therapy. With the incorporation of a tumor-targeting peptide sequence (F3) and a positron-emitting isotope (copper-64), the pharmacokinetic behavior of these micelles can be readily monitored by positron emission tomography imaging technique to confirm their specificity against cancer tissues. With further optimization, this micellar platform can have a broad clinical applicability owing to its biocompatibility, selectivity, and stability., (Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)- Published
- 2018
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23. Neural network disturbance observer-based distributed finite-time formation tracking control for multiple unmanned helicopters.
- Author
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Wang D, Zong Q, Tian B, Shao S, Zhang X, and Zhao X
- Abstract
The distributed finite-time formation tracking control problem for multiple unmanned helicopters is investigated in this paper. The control object is to maintain the positions of follower helicopters in formation with external interferences. The helicopter model is divided into a second order outer-loop subsystem and a second order inner-loop subsystem based on multiple-time scale features. Using radial basis function neural network (RBFNN) technique, we first propose a novel finite-time multivariable neural network disturbance observer (FMNNDO) to estimate the external disturbance and model uncertainty, where the neural network (NN) approximation errors can be dynamically compensated by adaptive law. Next, based on FMNNDO, a distributed finite-time formation tracking controller and a finite-time attitude tracking controller are designed using the nonsingular fast terminal sliding mode (NFTSM) method. In order to estimate the second derivative of the virtual desired attitude signal, a novel finite-time sliding mode integral filter is designed. Finally, Lyapunov analysis and multiple-time scale principle ensure the realization of control goal in finite-time. The effectiveness of the proposed FMNNDO and controllers are then verified by numerical simulations., (Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
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24. Gemtuzumab Ozogamicin (GO) Inclusion to Induction Chemotherapy Eliminates Leukemic Initiating Cells and Significantly Improves Survival in Mouse Models of Acute Myeloid Leukemia.
- Author
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Zhang CC, Yan Z, Pascual B, Jackson-Fisher A, Huang DS, Zong Q, Elliott M, Fan C, Huser N, Lee J, Sung M, and Sapra P
- Subjects
- Aminoglycosides therapeutic use, Animals, Antibodies, Monoclonal, Humanized therapeutic use, Antineoplastic Agents, Immunological therapeutic use, Cell Line, Tumor, Cell Survival drug effects, Disease Models, Animal, Female, Gemtuzumab, Humans, Induction Chemotherapy, Leukemia, Myeloid, Acute drug therapy, Leukemia, Myeloid, Acute mortality, Mice, Mice, Knockout, Molecular Targeted Therapy, Neoplasm, Residual pathology, Phenotype, Xenograft Model Antitumor Assays, fms-Like Tyrosine Kinase 3 antagonists & inhibitors, fms-Like Tyrosine Kinase 3 metabolism, Aminoglycosides pharmacology, Antibodies, Monoclonal, Humanized pharmacology, Antineoplastic Agents, Immunological pharmacology, Leukemia, Myeloid, Acute metabolism, Leukemia, Myeloid, Acute pathology, Neoplastic Stem Cells drug effects, Neoplastic Stem Cells metabolism
- Abstract
Gemtuzumab ozogamicin (GO) is an anti-CD33 antibody-drug conjugate for the treatment of acute myeloid leukemia (AML). Although GO shows a narrow therapeutic window in early clinical studies, recent reports detailing a modified dosing regimen of GO can be safely combined with induction chemotherapy, and the combination provides significant survival benefits in AML patients. Here we tested whether the survival benefits seen with the combination arise from the enhanced reduction of chemoresidual disease and leukemic initiating cells (LICs). Herein, we use cell line and patient-derived xenograft (PDX) AML models to evaluate the combination of GO with daunorubicin and cytarabine (DA) induction chemotherapy on AML blast growth and animal survival. DA chemotherapy and GO as separate treatments reduced AML burden but left significant chemoresidual disease in multiple AML models. The combination of GO and DA chemotherapy eliminated nearly all AML burden and extended overall survival. In two small subsets of AML models, chemoresidual disease following DA chemotherapy displayed hallmark markers of leukemic LICs (CLL1 and CD34). In vivo, the two chemoresistant subpopulations (CLL1+/CD117- and CD34+/CD38+) showed higher ability to self-renewal than their counterpart subpopulations, respectively. CD33 was coexpressed in these functional LIC subpopulations. We demonstrate that the GO and DA induction chemotherapy combination more effectively eliminates LICs in AML PDX models than either single agent alone. These data suggest that the survival benefit seen by the combination of GO and induction chemotherapy, nonclinically and clinically, may be attributed to the enhanced reduction of LICs., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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25. Control-oriented modeling and adaptive backstepping control for a nonminimum phase hypersonic vehicle.
- Author
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Ye L, Zong Q, Tian B, Zhang X, and Wang F
- Abstract
In this paper, the nonminimum phase problem of a flexible hypersonic vehicle is investigated. The main challenge of nonminimum phase is the prevention of dynamic inversion methods to nonlinear control design. To solve this problem, we make research on the relationship between nonminimum phase and backstepping control, finding that a stable nonlinear controller can be obtained by changing the control loop on the basis of backstepping control. By extending the control loop to cover the internal dynamics in it, the internal states are directly controlled by the inputs and simultaneously serve as virtual control for the external states, making it possible to guarantee output tracking as well as internal stability. Then, based on the extended control loop, a simplified control-oriented model is developed to enable the applicability of adaptive backstepping method. It simplifies the design process and releases some limitations caused by direct use of the no simplified control-oriented model. Next, under proper assumptions, asymptotic stability is proved for constant commands, while bounded stability is proved for varying commands. The proposed method is compared with approximate backstepping control and dynamic surface control and is shown to have superior tracking accuracy as well as robustness from the simulation results. This paper may also provide a beneficial guidance for control design of other complex systems., (Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2017
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26. Knockdown of Dynamitin in testes significantly decreased male fertility in Drosophila melanogaster.
- Author
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Wu CH, Zong Q, Du AL, Zhang W, Yao HC, Yu XQ, and Wang YF
- Subjects
- Animals, Cell Nucleus metabolism, Dyneins metabolism, Fertility, Gene Expression Regulation, Male, Mitochondria metabolism, Spermatids metabolism, Spermatogenesis, Tubulin metabolism, Drosophila Proteins metabolism, Drosophila melanogaster physiology, Gene Knockdown Techniques, Intermediate Filament Proteins metabolism, Testis physiology
- Abstract
Dynamitin (Dmn) is a major component of dynactin, a multiprotein complex playing important roles in a variety of intracellular motile events. We previously found that Wolbachia bacterial infection resulted in a reduction of Dmn protein. As Wolbachia may modify sperm in male hosts, we speculate that Dmn may have a function in male fertility. Here we used nosGal4 to drive Dmn knock down in testes of Drosophila melanogaster to investigate the functions of Dmn in spermatogenesis. We found that knockdown of Dmn in testes dramatically decreased male fertility, overexpression of Dmn in Wolbachia-infected males significantly rescued male fertility, indicating an important role of Dmn in inducing male fertility defects following Wolbachia infection. Some scattered immature sperm with late canoe-shaped head distributed in the end of Dmn knockdown testis and only about half mature sperm were observed in the Dmn knockdown testis relative to those in the control. Transmission electron microscopy (TEM) exhibited fused spermatids in cysts and abnormal mitochondrial derivatives. Immunofluorescence staining showed significantly less abundance of tubulin around the nucleus of spermatid and scattered F-actin cones to different extents in the individualization complex (IC) during spermiogenesis in Dmn knockdown testes, which may disrupt the nuclear condensation and sperm individualization. Since dynein-dynactin complex has been shown to mediate transport of many cellular components, including mRNAs and organelles, these results suggest that Dmn may play an important role in Drosophila spermiogenesis by affecting transport of many important cytoplasmic materials., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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27. Decentralized finite-time attitude synchronization for multiple rigid spacecraft via a novel disturbance observer.
- Author
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Zong Q and Shao S
- Abstract
This paper investigates decentralized finite-time attitude synchronization for a group of rigid spacecraft by using quaternion with the consideration of environmental disturbances, inertia uncertainties and actuator saturation. Nonsingular terminal sliding mode (TSM) is used for controller design. Firstly, a theorem is proven that there always exists a kind of TSM that converges faster than fast terminal sliding mode (FTSM) for quaternion-descripted attitude control system. Controller with this kind of TSM has faster convergence and reduced computation than FTSM controller. Then, combining with an adaptive parameter estimation strategy, a novel terminal sliding mode disturbance observer is proposed. The proposed disturbance observer needs no upper bound information of the lumped uncertainties or their derivatives. On the basis of undirected topology and the disturbance observer, decentralized attitude synchronization control laws are designed and all attitude errors are ensured to converge to small regions in finite time. As for actuator saturation problem, an auxiliary variable is introduced and accommodated by the disturbance observer. Finally, simulation results are given and the effectiveness of the proposed control scheme is testified., (Copyright © 2016. Published by Elsevier Ltd.)
- Published
- 2016
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28. New bioactive flavonoid glycosides isolated from the seeds of Lepidium apetalum Willd.
- Author
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Shi P, Chao L, Wang T, Liu E, Han L, Zong Q, Li X, Zhang Y, and Wang T
- Subjects
- Hep G2 Cells, Humans, Molecular Structure, Structure-Activity Relationship, Triglycerides metabolism, Flavonoids chemistry, Glycosides chemistry, Lepidium chemistry, Seeds chemistry
- Abstract
Ten flavonoid glycosides, apetalumosides A (1), B1-B7 (2-8), and C (9), quercetin 3-O-(2,6-di-O-β-D-glucopyranosyl)-β-D-glucopyranoside (10), were obtained from the seeds of Lepidium apetalum Willd. Their structures were elucidated by chemical and spectroscopic methods (UV, IR, NMR, and HRESI-TOF-MS). 1-9 were new isolates. The NMR data for 10 was reported here for the first time. On the other hand, activity screening results showed that 1-3 and 10 had triglyceride accumulation inhibitory effects in HepG2 cells. Preliminary structure-activity relationship study revealed that 7-hydroxyl group is an essential moiety., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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29. Continuous high order sliding mode controller design for a flexible air-breathing hypersonic vehicle.
- Author
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Wang J, Zong Q, Su R, and Tian B
- Subjects
- Computer Simulation, Computer-Aided Design, Equipment Design, Equipment Failure Analysis, Aircraft instrumentation, Algorithms, Feedback, Models, Theoretical
- Abstract
This paper investigates the problem of tracking control with uncertainties for a flexible air-breathing hypersonic vehicle (FAHV). In order to overcome the analytical intractability of this model, an Input-Output linearization model is constructed for the purpose of feedback control design. Then, the continuous finite time convergence high order sliding mode controller is designed for the Input-Output linearization model without uncertainties. In addition, a nonlinear disturbance observer is applied to estimate the uncertainties in order to compensate the controller and disturbance suppression, where disturbance observer and controller synthesis design is obtained. Finally, the synthesis of controller and disturbance observer is used to achieve the tracking for the velocity and altitude of the FAHV and simulations are presented to illustrate the effectiveness of the control strategies., (Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2014
- Full Text
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30. Direct determination of mercury in cosmetic samples by isotope dilution inductively coupled plasma mass spectrometry after dissolution with formic acid.
- Author
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Gao Y, Shi Z, Zong Q, Wu P, Su J, and Liu R
- Abstract
A new method was proposed for the accurate determination of mercury in cosmetic samples based on isotopic dilution (ID)-photochemical vapor generation (PVG)-inductively coupled plasma mass spectrometry (ICP MS) measurement. Cosmetic samples were directly dissolved in formic acid solution and subsequently subjected to PVG for the reduction of mercury into vapor species following by ICP MS detection. Therefore, the risks of analyte contamination and loss were avoided. Highly enriched (201)Hg isotopic spike is added to cosmetics and the isotope ratios of (201)Hg/(202)Hg were measured for the quantitation of mercury. With ID calibration, the influences originating from sample matrixes for the determination of mercury in cosmetic samples have been efficiently eliminated. The effects of several experimental parameters, such as the concentration of the formic acid, and the flow rates of carrier gas and sample were investigated. The method provided good reproducibility and the detection limits were found to be 0.6 pg mL(-1). Finally, the developed method was successfully applied for the determination of mercury in six cosmetic samples and a spike test was performed to verify the accuracy of the method., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
31. Transient knock down of checkpoint kinase 1 in hematopoietic progenitors is linked to bone marrow toxicity.
- Author
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Hu W, Zong Q, John-Baptiste A, and Jessen B
- Subjects
- Cell Differentiation, Cell Proliferation, Cells, Cultured, Checkpoint Kinase 1, Electroporation, Hematopoiesis, Hematopoietic Stem Cells cytology, Hematopoietic Stem Cells physiology, Humans, RNA, Small Interfering genetics, Bone Marrow drug effects, Hematopoietic Stem Cells enzymology, Protein Kinases physiology
- Abstract
Checkpoint kinase 1 (Chk1) is required for both intra-S phase and G2/M checkpoints in cell cycle, and plays critical roles in maintaining genomic stability and transducing DNA damage response. Chk1 deficiency has been shown to inhibit T-cell differentiation and resulted in severe anemia in a Chk1 heterozygous mouse model. To date, there has been a good correlation between Chk1 inhibition and in vitro bone marrow toxicity among small molecule inhibitors. To better understand the role of Chk1 in hematopoiesis, we conducted transient Chk1 gene silencing in human bone marrow progenitor cells using siRNA and electroporation. At 48h post electroporation, approximately 70% inhibition of Chk1 was confirmed using real-time RT-PCR and immunoblotting, which resulted in more than 60% reduction in cell count when compared to the non-specific siRNA control on day 6 post-electroporation. This result was confirmed using a colony forming unit assay, where reduced number in both erythroid and granulocyte colonies was observed with Chk1 siRNA treatment. The Chk1 gene inhibition in bone marrow progenitor cells resulted in significant induction of apoptosis, but not cell cycle arrest, as assessed using flow cytometry. In this study an effective method to knock down a gene of interest was established in hard-to-transfect hematopoietic stem cells. Furthermore, our results support a direct role of Chk1 in maintaining normal hematopoiesis in the bone marrow., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2011
- Full Text
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32. Determination of granulocyte colony stimulating factor and its antibody in human serum samples using the BIAcore 3000 biosensor.
- Author
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Ahmad A, Zong Q, Rock M, McLean M, and Breau A
- Subjects
- Antigen-Antibody Reactions, Biosensing Techniques standards, Calibration, Granulocyte Colony-Stimulating Factor immunology, Humans, Reference Standards, Surface Plasmon Resonance, Autoantibodies blood, Biosensing Techniques methods, Granulocyte Colony-Stimulating Factor blood, Isoantibodies blood
- Published
- 2004
- Full Text
- View/download PDF
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