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Rapid control of black and odorous substances from heavilypolluted sediment by oxidation:Efficiency and effects

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Frontiers of Environmental Science & Engineering 2019年第6期13卷 91-101页

作者： Kun Li Min Yang Jianfeng Peng Ruiping Liu Tista Prasai Joshi Yaohui Bai Huijuan Liu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100039China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China Nepal Academy of Science and Technology KhumaltarLalitpur 44700Nepal

The control ofblack and odorous substances in sediments is of crucial importance to improve the urban ecological landscape and to restore water environments *** this study,chemical oxidation by the oxidants NaClO,H2O2,and KMnO4 was proposed to achieve rapid control of black and odorous substances in heavily-polluted *** indicate that NaClO and KMnO4 are effective at removing Fe(II)and acid volatile *** removal efficiencies of Fe(II)and AVS were determined to be 45.2%,94.1%,and 93.7%,89.5%after 24-h exposure to NaClO and KMnO4 at 0.2 mmol/g,***,rapid oxidation might accelerate the release of pollutants from *** release of organic matters and phosphorus with the maximum ratios of 22.1%and 51.2%was observed upon NaClO oxidation at 0.4 mmol/***,the introduction of oxidants contributed to changes in the microbial community composition in *** oxidation by NaClO and KMnO4 at 0.4 mmol/g,the Shannon index decreased from 6.72 to 5.19 and 4.95,whereas the OTU numbers decreased from 2904 to 1677 and 1553,***,H2O2 showed a lower effect on the removal of black and odorous substances,pollutant release,and changes in sediment *** study illustrates the effects of oxidant addition on the characteristics of heavily polluted sediments and shows that chemical oxidants may be an option to achieve rapid control of black and odorous substances prior to remediation of water environments.

关键词： oxidants Heavily polluted sediment Black and odorous substances Release behaviors Microorganism

Recent advances in radical-mediated [2+2+m] annulation of 1,n-enynes

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Science China Chemistry 2019年第11期62卷 1463-1475页

作者： Chong-Hui Xu Yang Li Jin-Heng Li Jian-Nan Xiang Wei Deng State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China

1,n-Enynes are a versatile class of unsaturated hydrocarbons that found broad applications in the synthetic community of natural products,biologically active structures and functional *** methods for the transformations of 1,n-enynes include the radical-mediated[2+2+m]annulation reaction as they are particularly efficient accesses to functionalized polycyclic *** herein highlighted recent process in the radical-mediated[2+2+m]annulation of 1,n-enynes,including[2+2+1]and[2+2+2]modes,for the construction of five-to six-membered-ring-fused polycyclic ***,the mechanisms for these transformations were described.

关键词： radical annulation oxidants 1 n-enynes polycycles

Partial oxidation of methane by photocatalysis

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Chinese Chemical Letters 2024年第1期35卷 153-168页

作者： Zhongshan Yang Qiqi Zhang Hui Song Xin Chen Jiwei Cui Yanhui Sun Lequan Liu Jinhua Ye TJU-NIMS International Collaboration Laboratory School of Materials Science and EngineeringTianjin UniversityTianjin 300072China International Center for Materials Nanoarchitectonics(WPI-MANA) National Institute for Materials Science(NIMS)1-1 NamikiIbaraki 3050047Japan Zhejiang LAMP Co. Ltd.Wenzhou 325206China

Methane chemistry is one of the“Holy Grails of catalysis”.It is highly desirable but challenge to transform methane into value-added chemicals,because of its high C-H bonding energy(435 kJ/mol),lack ofπbonding or unpaired ***,commercial methane conversion is usually carried out in harsh conditions with enormous energy *** partial oxidation of methane to liquid oxygenates(PPOMO)is a future-oriented technology towards realizing high efficiency and high selectivity under mild *** selection of oxidant is crucial to the PPOMO ***,attentions are paid to the research progress of PPOMO with various oxidants(O_(2),H_(2)O,H_(2)O_(2)and other oxidants).Moreover,the activation of the selected oxidants is also highly ***,we summarized the methane activation mechanisms focusing on the C-H bond that was broken mainly by·OH radical,O-specie or photogenerated hole(h+).Finally,the challenges and prospects in this subject are briefly discussed.

关键词： Partial oxidation of methane Photocatalysis Liquid oxygenates oxidants C-H activation

Exercise-induced oxidative stress:Friend or foe?

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Journal of Sport and Health Science 2020年第5期9卷 415-425页

作者： Scott K.Powers Rafael Deminice Mustafa Ozdemir Toshinori Yoshihara Matthew P.Bomkamp Hayden Hyatt Department of Applied Physiology and Kinesiology University of FloridaGainesvilleFL32608USA Department of Physical Education State University of LondrinaLondrina10011Brazil Department of Exercise and Sport Sciences Hacettepe UniversityAnkara06800Turkey Department of Exercise Physiology Juntendo UniversityTokyo270-1695Japan

The first report demonstrating that prolonged endurance exercise promotes oxidative stress in humans was published more than 4 decades *** this discovery,many ensuing investigations have corroborated the fact that muscular exercise increases the production of reactive oxygen species(ROS)and results in oxidative stress in numerous tissues including blood and skeletal *** several tissues may contribute to exercise-induced ROS production,it is predicted that muscular contractions stimulate ROS production in active muscle fibers and that skeletal muscle is a primary source of ROS production during *** contraction-induced ROS generation is associated with(1)oxidant damage in several tissues(e.g.,increased protein oxidation and lipid peroxidation),(2)accelerated muscle fatigue,and(3)activation of biochemical signaling pathways that contribute to exercise-induced adaptation in the contracting muscle *** our understanding of exercise and oxidative stress has advanced rapidly during the last decades,questions remain about whether exercise-induced increases in ROS production are beneficial or harmful to *** review addresses this issue by discussing the site(s)of oxidant production during exercise and detailing the health consequences of exercise-induced ROS production.

关键词： Hormesis oxidants Radicals Reactive oxygen species Skeletal muscle

Bioactive compounds from marine Streptomyces sp. VITPSA as therapeutics

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Frontiers in Biology 2017年第4期12卷 280-289页

作者： S. Pooja T. Aditi S. Jemimah Naine C. Subathra Devi School of Biosciences and Technology VIT University Tamil Nadu India

BACKGROUND： Marine actinomycetes are efficient producers of new secondary metabolites that show different biological activities, including antibacterial, antifungal, anticancer, insecticidal, and enzyme inhibition activities. METHODS： The morphological, physiological, and biochemical properties of the strain Streptomyees sp. VITPSA were confirmed by conventional methods. Antibacterial, anti-oxidant, anti-inflammatory, anti-diabetic, and cytotoxic activities of Streptomyces sp. VITPSA extract were determined. The media were optimized for the production of secondary metabolites. Characterization and identification of secondary metabolites were conducted by high-performance liquid chromatography, gas chromatography-mass spectroscopy, and Fourier transform infrared spectroscopy analysis. RESULTS： The strain showed significant antibacterial, anti-oxidant, and cytotoxic activities, moderate anti-inflammatory activity, and no satisfactory anti-diabetic activity. The ethyl acetate extract of Streptomyces sp. VITPSA showed maximum antibacterial activity against two gram-positive and gram-negative bacteria at 0.5 mg/mL. The antioxidant potential of the crude extract exhibited strong reducing power activity at 0.5 mg/mL with 95.1% inhibition. The cytotoxic effect was found to be an ICso of 50 gg/mL on MCF-7 cell lines. Experimental design of optimization by one-factor analysis revealed the most favorable sucrose, yeast extract, pH （7.25）, and temperature （28~C） conditions for the effective production of secondary metabolites. CONCLUSION： This study revealed that Streptomyces sp. VITPSA is an excellent source of secondary metabolites with various bioactivities.

关键词： Marine actinomycetes bioactive compounds pathogens oxidants

Effects of nitric oxide on reproductive organs and related physiological processes

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Asian pacific Journal of Reproduction 2020年第4期9卷 159-165页

作者： Ayoob Rostamzadeh Reza Ahmadi Mahdi Heydari Amir Raoofi Student Research Committee Department of Anatomical SciencesFaculty of MedicineIran University of Medical SciencesTehranIran Clinical Biochemistry Research Center Basic Health Sciences InstituteShahrekord University of Medical SciencesShahrekordIran Leishmaniasis Research Center Department of AnatomySabzevar University of Medical SciencesSabzevarIran

Nitric oxide(NO),a member of the reactive nitrogen species family,plays a role in several physiologic processes,including vasculogenesis and angiogenesis,growth and puberty,and senescence and *** plays an important role in the production of ovarian steroids,ovulation,and follicular *** other words,increased activity of nitric oxide synthase(NOS)leads to an increased amount of NO,which triggers production of prostaglandins and inflammatory cascades which facilitate follicular rupture and *** concentration elevation inhibits steroid synthesis in luteal and granulosa *** NO is a major paracrine mediator of various biological processes,as well as a key factor in both the reproductive cycle and embryo implantation,oversynthesis of NO in the uterus results in toxicity and inflammation in epithelial cells and immunorejection of *** the male physiological system,NO synthesized by NOS plays a major role in erectile function and androgen secretion,as well as semen parameters,and oocyte junction to the ***,this supposedly simple molecule is involved in a number of other functions,such as germ cell evolution,connections between sertoli cells and germ cells in the blood-testis barrier,homodynamic contraction,and germ cell ***,NO is considered a key factor in male fertility due to its widespread distribution in both normal and diseased testis *** difference of expression level of NOS in normal and pathological states is a probable cause of fertility destructive processes.

关键词： Reproduction Nitric oxide Nitric oxide synthase Cell signaling oxidants

The importance of “first-blood circulation stage”, a new insight into the pathogenesis of clinical manifestations of preeclampsia

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Advances in Bioscience and Biotechnology 2012年第7期3卷 945-950页

作者： Lucijan Mohorovic Vladimir Micovic Department of Environmental Medicine University of Rijeka School of Medicine Rijeka Croatia

The tested hypothesis points out that exposure to environmental toxic substances originating from coal or other fossil fuels burning is the most decisive for the impacts of the metabolic synergy of nitrogen oxides as oxidants that cause hemoglobin oxidation to methemoglobin, and sulphur dioxide metabolites as inhibitors of antioxidants, in the bloodstream throughout the period of pregnancy. The main difference between the present three-stage hypothesis and other hypotheses is the assertion that, in the pathogenesis of early and late complicated pregnancy, methemoglobin takes on an important role. Methemoglobin by itself and from heme, redox-active ferric iron as a product of methemoglobin catabolism, has prooxidant properties and causes important structural and functional changes in the vascular endothelium, such as growth arrest, senescence, morphological alterations and cell apoptosis. Our own prospective study of methemoglobin in pregnancy revealed a significant rise and correlation between the ground level of SO2 and the level of methemoglobin: >1.5 g/L (r = 0.72, p 2, NOx, NO, NO2 and others) and that is an early biomarker of the identification of women with a pregnancy risk, and having an significant role upon adverse effects on mother and fetus health.

关键词： Methemoglobinemia Mother and Fetal Preeclampsia Three-Stage Disorders Environmental oxidants Biomarker Nitrogen and Sulphur Synergy

Inflammation and reactive oxygen species in cardiovascular disease

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World Journal of Cardiology 2010年第12期2卷 408-410页

作者： Bradley T Andresen Department of Internal Medicine 1 Medical Pharmacology and Physiology and Harry S Truman VAMC

Reactive oxygen species(ROS)have long been proposed to be mediators of experimental cardiovascular *** is also a wealth of data indicating that ROS are involved in clinical cardiovascular ***,multiple clinical studies have shown little benefit from anti-oxidant treatments,whereas nearly all experimental studies have shown a marked effect of anti-oxidant *** reason for this discrepancy is that ROS are produced through multiple different mechanisms of which some are clinically beneficial;thus,in a defined experimental system where predominately pathological ROS are generated does not mimic a clinical setting where there are likely to be multiple ROS generating systems producing beneficial and pathological *** inhibition of ROS would not be expected to have the same result in these two situations;ergo,it is important to understand the molecular mechanism underlying the production of ROS so that clinical treatments can be tailored to target the pathological production of *** such example of this in cardiovascular biology is tissue specific inflammation-mediated ROS *** and the following series of articles discuss the current understanding of the role of ROS in cardiovascular disease,specifically focusing on the molecular mechanisms of ROS generation and the actions of ROS within the cardiovascular *** there are still many areas with regard to the effects of ROS in the cardiovascular system that are not completely understood,there is a wealth of data suggesting that blocking pathological ROS production is likely to have beneficial clinical effects compared to traditional anti-oxidants.

关键词： Anti-oxidants Inflammation oxidants Pathology Reactive oxygen species

Telomerase enzyme in aging and cancer

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Aging Communications 2022年第4期4卷 26-29页

作者： Cagri Baris Gunec Sun Yat-sen University Zhongshan School of MedicineGuangzhou 510080China.

Telomerase is an enzyme that maintains the length of telomeres at the ends of *** are protective caps at the ends of chromosomes that keep genetic information intact,enable cells to multiply and provide insight into some of the mysteries of ageing and *** activity affects ageing and cancer development in humans by preventing telomeres from becoming too short,which can lead to cellular senescence and *** telomerase is suppressed,cancer cells die,and telomerase inhibitors can be used to kill human breast and prostate cancer cells grown in the *** have also found an association between shorter telomeres,a decreased overall lifespan,and an increased risk of cardiovascular disease and infectious *** research linking telomere shortening to the ageing process,additional research is needed to fully understand the role of telomerase in the ageing process,including whether or not it is the cause of these *** variables,such as oxidative stress,glycation,and inflammation,also contribute to the ageing process and may explain the remaining 33 percent of the variance in the probability of passing *** authors of this paper discuss the current understanding of telomerase enzyme activity and its effects on ageing and cancer,as well as the implications of telomerase research and the potential for developing innovative drugs and gene therapies.

关键词： telomerase ageing cancer telomeres chromosomes,DNA oxidants glycation