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Oxidative stress and diabetes: antioxidative strategies

Pengju Zhang, Tao Li, Xingyun Wu, Edouard C. Nice, Canhua Huang, Yuanyuan Zhang

《医学前沿（英文）》 2020年第14卷第5期页码 583-600 doi: 10.1007/s11684-019-0729-1

摘要： Diabetes mellitus is one of the major public health problems worldwide. Considerable recent evidence suggests that the cellular reduction–oxidation (redox) imbalance leads to oxidative stress and subsequent occurrence and development of diabetes and related complications by regulating certain signaling pathways involved in β-cell dysfunction and insulin resistance. Reactive oxide species (ROS) can also directly oxidize certain proteins (defined as redox modification) involved in the diabetes process. There are a number of potential problems in the clinical application of antioxidant therapies including poor solubility, storage instability and non-selectivity of antioxidants. Novel antioxidant delivery systems may overcome pharmacokinetic and stability problem and improve the selectivity of scavenging ROS. We have therefore focused on the role of oxidative stress and antioxidative therapies in the pathogenesis of diabetes mellitus. Precise therapeutic interventions against ROS and downstream targets are now possible and provide important new insights into the treatment of diabetes.

关键词： diabetes oxidative stress redox modification antioxidative therapy novel antioxidant delivery

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EMBRYOGENESIS ABUNDANT FAMILY GENE FROM PONCIRUS TRIFOLIATA, CONFERS ENHANCED DROUGHT TOLERANCE BY ENHANCING ANTIOXIDANT

《农业科学与工程前沿（英文）》 2021年第8卷第2期

摘要：

Late embryogenesis abundant (LEA) genes encode highly hydrophilic proteins that are essential in abiotic stress responses. However, most LEA genes in higher plants have not yet been investigated. This study identified an LEA family gene (PtrLEA7) from Poncirus trifoliata and studied its function in drought tolerance. The full-length coding sequence of PtrLEA7 was 420 bp encoding a protein of 139 amino acids. Phylogenetic analysis shows that PtrLEA7 protein belongs to the LEA_4 subfamily. Expression profiling by qPCR found that PtrLEA7 was strongly induced by dehydration, cold and ABA treatments, and slightly induced by salt stress. Subcellular localization reveals that PtrLEA7 protein was located in both cytoplasm and nucleus. To investigate its function, transgenic plants of both tobacco and Poncirus trifoliata overexpressing PtrLEA7 were obtained. Stress tolerance assays show that overexpression lines had enhanced dehydration and drought tolerance compared with wild type plants, indicating that PtrLEA7 positively regulates drought tolerance. In addition, transgenic plants had much higher expression levels of three antioxidant enzyme genes (CAT, SOD and POD) and significantly increased catalase enzyme activity, accompanied by reduced reactive oxygen species accumulation in comparison with wild type plants. Collectively, this study demonstrates that PtrLEA7 can confer enhanced drought tolerance partially via enhancing antioxidant capacity.

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Polyamines and antioxidant defense system are associated with cold tolerance in centipedegrass

Jingjing CHEN, Junyang FANG, Zhenfei GUO, Shaoyun LU

《农业科学与工程前沿（英文）》 2018年第5卷第1期页码 129-138 doi: 10.15302/J-FASE-2017197

摘要： Physiological responses to low temperature were analyzed in a chilling-tolerant centipedegrass ( ) accession, Shao Guan (SG), in comparison to the commercial cultivar, Common. Lower levels of ion leakage and higher chlorophyll (Chl) concentration were observed in SG than in Common during chilling stress. The maximum photochemical efficiency, the actual photosystem II (PSII) efficiency, photochemical quenching efficiency, and net photosynthetic rate were decreased during chilling stress in both genotypes, with higher levels of these parameters shown by SG than Common. In addition, higher activities of superoxide dismutase (SOD), catalase (CAT), ascorbate-peroxidase (APX) and glutathione reductase (GR), and higher concentrations of ascorbic acid (AsA) and glutathione (GSH) were observed in SG than in Common. Moreover, higher concentrations of putrescine (Put), spermidine (Spd), and spermine (Spm) were observed in SG than in Common. Correlation analysis indicated that SOD, CAT, APX and GR activities, and AsA and GSH concentrations showed high correlation to Put, while APX, GR, and AsA concentrations were correlated to Spd. Exogenous Put or Spd increased antioxidant enzyme activities and chilling tolerance. The results suggested that polyamine-regulated antioxidants are important for chilling tolerance in centipedegrass and protect plants against chilling induced oxidative damage.

关键词： antioxidants centipedegrass chilling photosynthesis polyamines

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OVEREXPRESSION OF

Tonglu WEI, Dalong GUO, Jihong LIU

《农业科学与工程前沿（英文）》页码 236-246 doi: 10.15302/J-FASE-2020368

摘要： Late embryogenesis abundant (LEA) genes encode highly hydrophilic proteins that are essential in abiotic stress responses. However, most LEA genes in higher plants have not yet been investigated. This study identified an LEA family gene (PtrLEA7) from Poncirus trifoliata and studied its function in drought tolerance. The full-length coding sequence of PtrLEA7 was 420 bp encoding a protein of 139 amino acids. Phylogenetic analysis shows that PtrLEA7 protein belongs to the LEA_4 subfamily. Expression profiling by qPCR found that PtrLEA7 was strongly induced by dehydration, cold and ABA treatments, and slightly induced by salt stress. Subcellular localization reveals that PtrLEA7 protein was located in both cytoplasm and nucleus. To investigate its function, transgenic plants of both tobacco and Poncirus trifoliata overexpressing PtrLEA7 were obtained. Stress tolerance assays show that overexpression lines had enhanced dehydration and drought tolerance compared with wild type plants, indicating that PtrLEA7 positively regulates drought tolerance. In addition, transgenic plants had much higher expression levels of three antioxidant enzyme genes (CAT, SOD and POD) and significantly increased catalase enzyme activity, accompanied by reduced reactive oxygen species accumulation in comparison with wild type plants. Collectively, this study demonstrates that PtrLEA7 can confer enhanced drought tolerance partially via enhancing antioxidant capacity.

关键词： abiotic stress antioxidant drought late embryogenesis abundant Poncirus trifoliata

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Biodegradable polymethacrylic acid grafted psyllium for controlled drug delivery systems

Ranvijay KUMAR, Kaushlendra SHARMA

《化学科学与工程前沿（英文）》 2013年第7卷第1期页码 116-122 doi: 10.1007/s11705-013-1310-0

摘要： Polymethacrylic acid (PMA) was synthesized on the backbone of psyllium (Psy) by a microwave assisted method to prepare polymeric grafted materials designated as (Psy- -PMA). Various grades of Psy- -PMA were prepared by changing the degree of grafting from 35%–58% and the materials were then made into tablets. Swelling and biodegradability studies of the tablets were carried out. Acetyl salicylic acid was incorporated in the various Psy- -PMA samples and tablets were prepared to study the in vitro drug release in acidic (pH= 4), neutral (pH= 7), and basic (pH= 9) media. In the acidic medium, the swelling was more than 1300%. In addition, the biodegradable Psy- -PMA had the highest drug release in the acidic medium. This may be attributed to Fickian diffusion since the drug and the medium in which it was released have the same acidic nature.

关键词： psyllium acetyl salicylic acid in-vitro drug release swelling biodegradation

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Engineering platelet-mimicking drug delivery vehicles

Quanyin Hu, Hunter N. Bomba, Zhen Gu

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 624-632 doi: 10.1007/s11705-017-1614-6

摘要： Platelets dynamically participate in various physiological processes, including wound repair, bacterial clearance, immune response, and tumor metastasis. Recreating the specific biological features of platelets by mimicking the structure of the platelet or translocating the platelet membrane to synthetic particles holds great promise in disease treatment. This review highlights recent advancements made in the platelet-mimicking strategies. The future opportunities and translational challenges are also discussed.

关键词： drug delivery platelets nanomedicine bio-inspired biomimetic

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Gene delivery into isolated

Nan Zheng, Ziyuan Song, Yang Liu, Lichen Yin, Jianjun Cheng

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 521-528 doi: 10.1007/s11705-017-1612-8

摘要： The application of gene delivery materials has been mainly focused on mammalian cells while rarely extended to plant engineering. Cationic polymers and lipids have been widely utilized to efficiently deliver DNA and siRNA into mammalian cells. However, their application in plant cells is limited due to the different membrane structures and the presence of plant cell walls. In this study, we developed the cationic, -helical polypeptide that can effectively deliver DNA into both isolated protoplasts and intact leaves. The PPABLG was able to condense DNA to form nanocomplexes, and they exhibited significantly improved transfection efficiencies compared with commercial transfection reagent Lipofectamine 2000 and classical cell penetrating peptides such as poly(L-lysine), HIV-TAT, arginine9, and poly(L-arginine). This study therefore widens the utilities of helical polypeptide as a unique category of gene delivery materials, and may find their promising applications toward plant gene delivery.

关键词： α-helical polypeptide plant gene delivery protoplast intact leaves transfection

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Introduction to the special issue of the 2009 International Symposium on Crystal Engineering & Drug Delivery

Zhijian CHEN, Wei LI,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 1-1 doi: 10.1007/s11705-009-0306-2

摘要：

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Controlled drug delivery systems: the next 30 years

Yeonhee YUN,Byung Kook LEE,Kinam PARK

《化学科学与工程前沿（英文）》 2014年第8卷第3期页码 276-279 doi: 10.1007/s11705-014-1426-x

摘要： The drug delivery scientists need to reexamine the advances made during the past 60 years, analyze our current abilities, and design the future technologies that will propel us to achieve the next level of drug delivery technologies. History shows that the first generation (1G) of drug delivery research during 1950–1980 was quite productive, while the second generation (2G) technologies developed during 1980–2010 were not as prolific. The ultimate goal of drug delivery research is to develop clinically useful formulations to treat various diseases. Effective drug delivery systems can be developed by overcoming formulation barriers and/or biological barriers. The engineering approach has a limit in solving the problem, if biological difficulties are not clearly identified and understood. The third generation (3G) drug delivery systems will have to focus on understanding the biological barriers so that they can be overcome by engineering manipulation of the drug delivery systems. Advances in the next 30 years will be most accelerated by starting open dialogues without any preconceived ideas on drug delivery technologies. The new generation of drug delivery scientists needs to be aware of the successes and limitations of the existing technologies to design the new technologies for meaningful advances in the future.

关键词： drug delivery history formulation barriers nanotechnology clinical product

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Bioorthogonal chemistry based on-demand drug delivery system in cancer therapy

《化学科学与工程前沿（英文）》 2023年第17卷第4期页码 483-489 doi: 10.1007/s11705-022-2227-2

摘要： Benefiting from the advantage of taking place in biological environments without interfering with an innate biochemical process, the bioorthogonal reaction that commonly contains the “bond formation” and “bond cleavage” system has been widely used in targeted therapy for a variety of tumors. Herein, several prominent cases based on the bioorthogonal reaction that tailoring the metabolic glycoengineering tactics to modified cells for cancer immunotherapy, and the innovative tactics for reducing the metal ions’ toxic and side effects with microneedle patches will be highlighted. Based on these applications, the complexities, potential pitfalls, and opportunities of bioorthogonal chemistry in future cancer therapy will be evaluated.

关键词： bioorthogonal reaction cancer therapy metabolic glycoengineering bioorthogonal catalytic patch

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Effect of the new maternity insurance scheme on medical expenditures for caesarean delivery in Wuxi,

null

《医学前沿（英文）》 2016年第10卷第4期页码 473-480 doi: 10.1007/s11684-016-0479-

摘要：

Aiming to control rising medical expenditures and help improve China’s healthcare systems, this study examined whether a cap-based medical insurance scheme with shared financial interest between the insurance and healthcare providers is effective in containing hospitals’ C-section medical expenditures. We used 6547 caesarean delivery case records from a teaching tertiary-level general public hospital located in Wuxi, China (2004–2013), and used the Chow test to investigate the possibility of significant variation in mean medical expenditures for caesarean deliveries pre- and post-reform. We also used paired sample t-tests and linear regression models to compare the mean medical expenditures between insured and uninsured women undergoing caesarean delivery during the post-reform period. After the scheme’s implementation, medical expenditures for caesarean deliveries declined and the medical expenditures of women covered by the scheme were significantly lower than those of uninsured patients. These findings indicated the scheme’s effectiveness in minimizing caesarean delivery expenditures. The cap-based medical insurance scheme with shared financial interest between insurance and healthcare providers would likely steer healthcare providers’ behaviors in a more cost-effective direction.

关键词： maternity insurance scheme financial incentive caesarean delivery medical expenditure China

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Economic analysis of a hybrid solar-fuel cell power delivery system using tuned genetic algorithm

Trina SOM, Niladri CHAKRABORTY

《能源前沿（英文）》 2012年第6卷第1期页码 12-20 doi: 10.1007/s11708-012-0172-3

摘要： An economic evaluation of a network of distributed energy resources (DERs) comprising a microgrid structure of power delivery system in an Indian scenario has been made. The mathematical analysis is based on the application of tuned genetic algorithm (TGA). The analyses for optimal power operation pertaining to minimum cost have been made for two cases in Indian power delivery system. The first case deals with the consumers’ individual optimal operation of DERs, while in the second one, consumers altogether form a microgrid with the optimal supply of power from DERs. The total annual costs for these two cases are found to be economically competitive and encouraging. A reduction of approximately 5.7% in the annual cost has been obtained in the case of microgid system than that in the separately operating consumers’ system for a small locality of India. It is observed that the application of TGA results in a reduction of the minimum cost depicting an improved outcome in terms of energy economy.

关键词： distributed energy resources (DERs) microgrid tuned genetic algorithm (TGA)

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Antioxidant and antitumor effects and immunomodulatory activities of crude and purified polyphenol extract

Xiaohong Kou,Lihua Han,Xingyuan Li,Zhaohui Xue,Fengjuan Zhou

《化学科学与工程前沿（英文）》 2016年第10卷第1期页码 108-119 doi: 10.1007/s11705-016-1553-7

摘要： The antioxidant and antitumor effects as well as the immunomodulatory activities of crude and purified polyphenol extract from blueberries were investigated. The antioxidant and antitumor effects of the polyphenol extract were measured both and , and their effect on the immune systems of CD-1 tumor-bearing mice were also analyzed. assays demonstrated that blueberry purified polyphenol extract (BBPP) exhibited higher antioxidant activities than blueberry crude polyphenol extract (BBCP), but the opposite effect was observed . Both the and antitumor activity and the immunity assay showed that BBCP not only inhibited tumor growth, but also significantly improved the immunity of the mice. According to physical and histological studies, the CD-1 tumor-bearing mice treated with the polyphenol extract, especially high doses of BBCP experienced a higher quality of life than the positive control group (treated with cyclophosphamide). These results indicate that BBCP has significant antioxidant and antitumor activities and that it can enhance the immunity of CD-1 tumor-bearing mice.

关键词： crude polyphenol extract purified polyphenol extract blueberry antioxidant antitumor immunity

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Inhibition of NO emission by adding antioxidant mixture in

A. PRABU,R. B. ANAND

《能源前沿（英文）》 2015年第9卷第2期页码 238-245 doi: 10.1007/s11708-015-0356-8

摘要： In this paper, the effect of adding an antioxidant mixture in biodiesel as fuel, in a single cylinder, direct injection compression ignition engine was experimentally investigated and the level of pollutants in the exhaust and performance characteristics of the engine were analyzed. Nine test fuels were prepared with three antioxidants, namely, Succinimide (C H NO ), , dimethyl- -phenylenediamine-dihydrochloride (C H Cl N ), and -phenyl- -phenylenediamine (C H NHC H NH ) added to neat biodiesel at 500 parts per million (ppm), 1000 ppm and 2000 ppm and the observed experimental results were compared with those of neat biodiesel and neat diesel as base fuels. The comparison showed that NO emission was reduced drastically for the test fuels with the antioxidant addition of 2000 ppm. The maximum reduction of 10% of NO emission was observed for the antioxidant mixture in neat biodiesel, with a slight increase in unburned HC, CO and smoke opacity. In addition, the obtained experimental results reveal that the addition of two antioxidants as mixture in neat biodiesel caused improved NO emission reduction for all test fuels.

关键词： NO emission antioxidants Succinimide N N-dimethyl-p-phenylenediamine-dihydrochloride N-phenyl-p-phenylenediamine

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Zeolitic imidazolate framework-8 (ZIF-8) for drug delivery: A critical review

Simin Feng, Xiaoli Zhang, Dunyun Shi, Zheng Wang

《化学科学与工程前沿（英文）》 2021年第15卷第2期页码 221-237 doi: 10.1007/s11705-020-1927-8

摘要： Zeolitic imidazolate framework-8 (ZIF-8), composed of Zn ions and imidazolate ligands, is a class of metal-organic frameworks, which possesses a similar structure as conventional aluminosilicate zeolites. This material exhibits inherent porous property, high loading capacity, and pH-sensitive degradation, as well as exceptional thermal and chemical stability. Extensive research effort has been devoted to relevant research aspects ranging from synthesis methods, property characterization to potential applications of ZIF-8. This review focuses on the recent development of ZIF-8 synthesis methods and its promising applications in drug delivery. The potential risks of using ZIF-8 for drug delivery are also summarized.

关键词： zeolitic imidazolate framework-8 (ZIF-8) synthesis methods applications drug delivery