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New progress in roles of nitric oxide during hepatic ischemia reperfusion injury

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World Journal of Gastroenterology 2017年第14期23卷 2505-2510页

作者： Ya-Qi Zhang Ning Ding Yong-Fen Zeng Yuan-Yuan Xiang Mei-Wen Yang Fen-Fang Hong Shu-Long Yang Department of physiology Basic Medical CollegeNanchang University Medical experimental Teaching Center Jiangxi Medical CollegeNanchang University

Hepatic ischemia reperfusion injury (HIRI) is a clinical condition which may lead to cellular injury and organ dysfunction. The role of nitric oxide (NO) in HIRI is complicated and inconclusive. NO produced by endothelial nitric oxide synthase (eNOS) activation plays a protective role during early HIRI. But eNOS overexpression and the resulting excessive NO bioavailability can aggravate liver injury. NO induced by inducible nitric oxide synthase (iNOS) may have either a protective or a deleterious effect during the early phase of HIRI, but it may protect the liver during late HIRI. Here, we reviewed the latest findings on the role of NO during HIRI: (1) NO exerts a protective effect against HIRI by increasing NO bioavailability, downregulating p53 gene expression, decreasing inflammatory chemokines, reducing ROS via inhibiting the mitochondrial respiratory chain, activating sGC-GTP-cGMP signal pathway to reduce liver cell apoptosis, and regulating hepatic immune functions; (2) eNOS protects against HIRI by increasing NO levels, several eNOS/NO signal pathways (such as Akt-eNOS/NO, AMPK-eNOS/NO and HIF-1 alpha-eNOS/NO) participating in the anti-HIRI process, and inhibiting over-expression of eNOS also protects against HIRI; and (3) the inhibition of iNOS prevents HIRI. Thus, the adverse effects of NO should be avoided, but its positive effect in the clinical treatment of diseases associated with HIRI should be recognized.

关键词： Liver Hepatic ischemia reperfusion injury Nitric oxide Nitric oxide synthase

Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei Xiong Xuan Ye Hongzhang Cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

Environmental pollution and DNA methylation： carcinogenesis, clinical significance, and practical applications

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Frontiers of Medicine 2015年第3期9卷 261-274页

作者： Yi Cao laboratory of Molecular and experimental Pathology Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China

Environmental pollution is one of the main causes of human cancer. Exposures to environmental carcinogens result in genetic and epigenetic alterations which induce cell transformation. Epigenetic changes caused by environmental pollution play important roles in the development and progression of environmental pollution-related cancers. Studies on DNA methylation are among the earliest and most conducted epigenetic research linked to cancer. In this review, the roles of DNA methylation in carcinogenesis and their significance in clinical medicine were summarized, and the effects of environmental pollutants, particularly air pollutants, on DNA methylation were introduced. Furthermore, prospective applications of DNA methylation to environmental pollution detection and cancer prevention were discussed.

关键词： environmental pollution DNA methylation cancer biomarker diagnosis therapy prevention

Effects of Acetylcholine, Cytochalasin B and Amiprophosmethyl on Phloem Transport in Radish （Raphanus sativas）

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Journal of Integrative Plant Biology 2007年第4期49卷 550-555页

作者： Chong-Jun Yang Zhi-Xi Zhai Yu-Hai Guo Peng Gao laboratory of Crop physiology China Agricultural University Beijing 100094 China College of Agronomy Liaocheng University Liaocheng 252000 China State Key laboratory of Plant physiology and Biochemistry China Agricultural University Beijing 100094 China

We investigated the role of the ＂sieve tube-companion cell complex＂ lining the tube periphery, particularly the microfilament and microtubule, in assisting the pushing of phloem sap flow. We made a simple phloem transport system with a living radish plant, in which the conducting channel was exposed for local treatment with chemicals that are effective in modulating protoplasmic movement （acetylcholine, （ACh） a neurotransmitter in animals and insects; cytochalasin B, （CB） a specific inhibitor of many cellular responses that are mediated by microfilament systems and amiprophos-methyl, （APM） a specific inhibitor of many cellular responses that are mediated by microtubule systems）. Their effects on phloem transport were estimated by two experimental devices：（i） a comparison of changes in the amount of assimilates in terms of carbohydrates and ^14C-labeled photosynthetic production that is left in the leaf blade of treated plants; and （ii） distribution patterns of ^14C-labeled leaf assimilates in the phloem transport system. The results indicate that CB and APM markedly inhibited the transfer of photosynthetic product from leaf to root via the leaf vein, while ACh enhanced the transfer of photosynthetic product in low concentrations （5.0×10^-4 mol/L） but inhibited it in higher concentrations （2.0×10^-3 mol/L） from leaf to root via the leaf vein. Autoradiograph imaging clearly reveals that ACh treatment is more effective than the control, and both CB and APM treatments effectively inhibit the passage of radioactive assimilates. All of the results support the postulation that the peripheral protoplasm in the sieve tube serves not only as a passive semi-permeable membrane, but is also directly involved in phloem transport.

关键词： assimilate phloem protoplasm translocation vascular bundle.

experimental Study and Numerical Simulation of Polymer Flooding

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Fluid Dynamics & Materials Processing 2022年第6期18卷 1815-1826页

作者： Lei Bai Kai Li Ke Zhou Qingshan Wan Pengchao Sun Gaoming Yu Xiankang Xin Xinjiang Oilfield Company PetroChina(Experimental Testing Research Institute)Karamay834000China Xinjiang Conglomerate Reservoir laboratory Karamay834000China School of Petroleum Engineering Yangtze UniversityWuhan430100China

The numerical simulation of polymer flooding is a complex task as this process involves complex physical and chemical reactions,and multiple sets of characteristic parameters are required to properly set the *** present,such characteristic parameters are mainly obtained by empirical methods,which typically result in relatively large *** analyzing experimentally polymer adsorption,permeability decline,inaccessible pore volume,viscosity-concentration relationship,and rheology,in this study,a conversion equation is provided to convert the experimental data into the parameters needed for the numerical *** examples are provided to demonstrate the reliability of the proposed approach.

关键词： Polymer flooding oil displacement mechanism flooding experiment numerical simulation characteristic parameter

Small scale adeno-associated virusvector production for preclinical gene delivery based on chloroform precipitation

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Neural Regeneration Research 2022年第1期17卷 99-100页

作者： Marcus Davidsson Andreas Heuer Molecular Neuromodulation Department of Experimental Medical SciencesLund UniversityLundSweden Behavioural Neuroscience laboratory Department of Experimental Medical SciencesLund UniversityLundSweden

Gene therapy aims to introduce genetic information into a cell-type of interest to replace,correct,silence,or modify defective *** therapy in its broadest sense can theoretically prevent,halt,or cure any condition that affects *** addition to that,the introduction and/or manipulation of genes is one of the major research areas in biological sciences,aimed to deepen our knowledge on how biological systems *** advances have made it possible to induce changes ranging from manipulations of large stretches of the genome to the change of single *** gold-standard vehicles to bring this genetic information into the target cells are viral vectors.

关键词： replace Small mankind

Delayed treatment of secondary degeneration following acute optic nerve transection using a combination of ion channel inhibitors

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Neural Regeneration Research 2017年第2期12卷 307-316页

作者： Nathanael J.Yates Marcus K.Giacci Ryan L. O'Hare Doig Wissam Chiha Bethany E. Ashworth Jade Kenna Carole A. Bartlett Melinda Fitzgerald Department of experimental and Regenerative Neurosciences School of Animal Biology The University of Western Australia Crawley Western Australia Australia Department of experimental and Regenerative Neurosciences School of Anatomy Physiology and Human Biology The University of Western Australia Crawley Western Australia Australia

Studies have shown that a combined application of several ion channel inhibitors immediately after central nervous system injury can inhibit secondary degeneration. However, for clinical use, it is necessary to determine how long after injury the combined treatment of several ion channel inhibitors can be delayed and efficacy maintained. In this study, we delivered Ca^2＋ entry-inhibiting P2X7 receptor antagonist oxidized-ATP and AMPA receptor antagonist YM872 to the optic nerve injury site via an iPRECIO-@ pump immediately, 6 hours, 24 hours and 7 days after partial optic nerve transection surgery. In addition, all of the ion channel inhibitor treated rats were administered with calcium channel antagonist lomerizine hydrochloride. It is important to note that as a result of implantation of the particular pumps required for programmable delivery of therapeutics directly to the injury site, seromas occurred in a significant proportion of animals, indicating infection around the pumps in these animals. Improvements in visual function were observed only when treatment was delayed by 6 hours; phosphorylated Tau was reduced when treatment was delayed by 24 hours or 7 days. Improvements in structure of node/paranode of Ranvier and reductions in oxidative stress indicators were also only observed when treatment was delayed for 6 hours, 24 hours, or 7 days. Benefits of ion channel inhibitors were only observed with time-delayed treatment, suggesting that delayed therapy of Ca^2＋ ion channel inhibitors produces better neuroprotective effects on secondary degeneration, at least in the presence of seromas.

关键词： nerve regeneration optic nerve injury neurotrauma secondary degeneration seromas calcium channel inhibitor node of Ranvier Tau phosphorylation lipid peroxidation oxidative stress neural regeneration

Bacterial diversity in surface water of the Yellow Sea during and after a green alga tide in 2008

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Chinese Journal of Oceanology and Limnology 2011年第6期29卷 1147-1154页

作者：郭丛李富超姜鹏刘兆普秦松 Key laboratory of Marine Biology of Jiangsu Province Nanjing Agricultural University Key laboratory of experimental Marine Biology Institute of Oceanology Chinese Academy of Sciences

From May to August 2008, a large "green tide", consisting of the alga Ulva (Enteromorpha) prolifera, occurred in the Yellow Sea, China, affecting the local marine ecosystem and human activities. We investigated the influence of the green tide on the microbial community in the surface seawater, at four sites from July to August 2008, using bacterial 16S rRNA gene clone libraries. We sequenced 228 clones of unique patterns identified by restriction fragment length polymorphism (RFLP) techniques. The results show that 228 sequenced clones fell into six bacterial phyla:Proteobacteria, Bacteroidetes, Cyanobacteria, Verrucomicrobia, Actinobacteria, and Planctomycetes. Alphaproteobacteria (33%), Gammaproteobacteria (25%), Bacteroidetes (23%) and Cyanobacteria (9%) dominated the assemblage. Comparison between samples collected in July (during the tide) and those collected in August (after the tide) showed that, in the microbial community, diversities of Alphaproteobacteria and Cyanobacteria increased after the tide, while those of Gammaproteobacteria and Bacteroidetes decreased. These results indicate that the green tide influenced the growth of some bacteria, and provide information for further studies on the interactions and relationships between U. prolifera and the bacterial community. This study suggests that microbial community analysis is a good approach to monitoring green tides.

关键词： Ulvaprolifera 16S rRNA gene restriction fragment length polymorphism (RFLP) operationaltaxonomic unit (OTU)

Flares and magnetic non-potentiality of NOAA AR 11158

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Research in Astronomy and Astrophysics 2013年第2期13卷 226-238页

作者： Qiao Song Jun Zhang Shu-Hong Yang Yang Liu Key laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of Sciences W.W.Hansen experimental Physics laboratory Stanford University

Magnetic non-potentiality is important for understanding flares and other solar activities in active regions （ARs）. Five non-potential parameters, i.e. electric current, current helicity, source field, photospheric free energy, and angular shear, are calculated to quantify the non-potentiality of NOAA AR 11158. Benefitting from the high spatial resolution, high cadence and continuous temporal coverage of vector mag- netograms from the Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory, both the long-term evolution of the AR and the rapid change during flares are studied. We confirm that, compared with the magnetic flux, the magnetic non-potentiality has a closer connection with the flare, and the emerging flux regions are important for understanding the magnetic non-potentiality and flares. The main re- suits are as follows. （1） The vortex in the source field directly displays the deflection of the horizontal magnetic field. The deflection corresponds to the fast rotating sunspot with a time delay, which suggests that the sunspot rotation leads to an increase in the non-potentiality. （2） Two areas that have evident changes in the azimuth of the vector magnetic field are found near the magnetic polarity inversion line. The change rates of the azimuth are about 1.3° h-1 and 3.6° h-1, respectively. （3） Rapid and prominent increases are found in the variation of helicity during four flares in the regions where their initial brightening occurs. The recovery of the increases takes 3-4 h for the two biggest flares （X2.2 and M6.6）, but only takes about 2 h for the two other smaller flares （M2.2 and M1.6）.

关键词： Sun activity -- Sun flares -- Sun magnetic fields -- Sun photosphere -- sunspots