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Complex Mutation and Weak Selection together Determined the Codon Usage Bias in Bryophyte Mitochondrial Genomes

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Journal of Integrative Plant Biology 2010年第12期52卷 1100-1108页

作者： Bin Wang jing liu liang Jin Xue-Ying Feng Jian-Qun Chen State Key Laboratory of Pharmaceutical Biotechnology Department of Biology Nanjing University Nanjing 210093 China

Mutation and selection are two major forces causing codon usage biases. How these two forces influence the codon usages in green plant mitochondrial genomes has not been well investigated. In the present study, we surveyed five bryophyte mitochondrial genomes to reveal their codon usage patterns as well as the determining forces. Three interesting findings were made. First, comparing to Chara vulgaris, an algal species sister to all extant land plants, bryophytes have more G, C-ending codon usages in their mitochondrial genes. This is consistent with the generally higher genomic GC content in bryophyte mitochondria, suggesting an increased mutational pressure toward GC. Second, as indicated by Wright＇s Nc-GC3s plot, mutation, not selection, is the major force affecting codon usages of bryophyte mitochondrial genes. However, the real mutational dynamics seem very complex. Context-dependent analysis indicated that nucleotide at the 2nd codon position would slightly affect synonymous codon choices. Finally, in bryophyte mitochondria, tRNA genes would apply a weak selection force to fine-tune the synonymous codon frequencies, as revealed by data of Ser4-Pro-Thr-Val families. In summary, complex mutation and weak selection together determined the codon usages in bryophyte mitochondrial genomes.

关键词： Selection Nucleotide sequence Mutation Genomes Uses Forcing Plants Planting Wells Mitochondria

Neuroprotective effect of quercetin on beta-amyloid-induced PC12 cells injury and potential related mechanism

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中国药理学与毒理学杂志 2017年第10期31卷 1000-1001页

作者： Yang liu liang-jing liu Wei LI Li-xia SHEN Department of Pharmacy Hebei North University Zhangjiakou 075000 China Key Laboratory in neuropharmacology of Hebei province Zhangjiakou 075000 China

OBJECTIVE To explore the estrogen-like neuroprotective effects and the related mechanism of quercetin by using PC12 cells induced with Aβ25-35,provided thought and strategy for the drug therapy of *** Cells were cultured with Aβ25-35 for 24 h,17β-estradiol(0.1 μmol·L^(-1)),genistein(50 μmol·L^(-1)) and three different concentrations of quercetin(200 μmol·L^(-1),300 μmol·L^(-1) and400 μmol·L^(-1)) were respectively added after 24 *** effects of quercetin on activity of AD model were tested by *** stain and Western blot were used to detect the expression of estrogen receptors alpha and beta,p-ERK1/2 and apoptosis related *** mechanism of quercetin estrogen-like neuroprotective effects was detected using estrogen receptor antagonist ICI182,780 and MAPKK inhibitor *** The results revealed thatthe toxic effects showed in a dose-dependent increase of Aβ25-35 on PC12 *** with the control group,cells injury was observed after cultured with 10 μmol·L^(-1) Aβ25-35 for 24 h(P<0.01).The MTT results showed that 17β-estradiol,genistein and three different concentrations of quercetin could significantly enhance the cell survival rate compared with the model group(P<0.05).Compared with model group,Immunofluorescence and Western blot results show that quercetin could improve the estrogen receptor alpha and p-ERK1/2 protein expression(P<0.05),and the expression of estrogen receptor beta protein is increased without significant *** in the Western blot experiments,the ratio of Bcl-2 and Bax was increased and the expression of Caspase 3 was decreased(P<0.05).When estrogen receptor inhibition ICI182,780 were reduced,the expression of p-ERK1/2 was decreased(P<0.05) and the ratio of Bcl-2 and Bax was decreased,Caspase 3 protein expression was increased(P<0.05).In addition,pretreatment of cells with U0126 would reduce Bcl-2/Bax ratio and increase Caspase 3 protein expression increased(P<0.05).CONCLUSION Quercetin protect

关键词： quercetin Alzheimer disease estrogen receptor MAPK signal pathway apoptosis

Protective estrogen-like properties and mechanism of quercetin in rat cerebral cortex neurons

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中国药理学与毒理学杂志 2017年第10期31卷 994-995页

作者： liang-jing liu Ming ZHONG Li-xia SHEN Department of Pharmacy Hebei North University Zhangjiakou 075000 China Key laboratory in neuropharmacology of hebei province Zhangjiakou 075000 China

OBJECTIVE To investigate the effect of quercetin on primary cultured newborn rat cortex neuron cell which is estrogen depletion,and discuss the possible mechanism,to provide new ideas and strategies for developing a drug of neurodegenerative *** Rat cortex neurons were isolated from one day old Sprague Dawley rats and treated with estrogen,quercetin and estrogen receptor antagonists(ICI182,780).Cell viability was determined by MTT assay,neurite outgrowth was measured by fluorescent microsope and estrogen receptors were determine by Western *** Quercetin functions like estrogen to increase cortex neuronal cell viability,the Que(50,100μmol·L^(-1))group compared with the control group could significantly improve the activity of the cortical neurons(P<0.05).It can also increase neurite out growth,the Que(50,100μmol·L^(-1))group significantly promoted the formation of synapse,most of the neurons were full,and the synapses of neurons became thick,growth,and connect to a dense neural *** in the Western blot experiments,Que(50,100μmol·L^(-1))group could obviously increase the expression of estrogen receptor alpha protein,in addition,the neural protective effect of quercetin can be inhibited by ICI182,*** Quercetin like estrogen can protected cortex neuronal and the effect of quercetin on cortex neuronal cells was mediated by estrogen receptor alpha.

关键词： estrogen quercetin estrogen-like protection effect estrogen receptor cortex neuron

Neuronal conversion from glia to replenish the lost neurons

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Neural Regeneration Research 2024年第7期19卷 1446-1453页

作者： Shiyu liang jing Zhou Xiaolin Yu Shuai Lu Ruitian liu National Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijingChina School of Chemical Engineering University of Chinese Academy of SciencesBeijingChina Department of Geriatric Rehabilitation Beijing Rehabilitation HospitalCapital Medical UniversityBeijingChina

Neuronal injury,aging,and cerebrovascular and neurodegenerative diseases such as cerebral infarction,Alzheimer’s disease,Parkinson’s disease,frontotemporal dementia,amyotrophic lateral sclerosis,and Huntington’s disease are characte rized by significant neuronal *** rtunately,the neurons of most mammals including humans do not possess the ability to *** of lost neurons becomes an appealing therapeutic strategy to reve rse the disease *** of pluripotent neural stem cells can supplement the missing neurons in the brain,but it carries the risk of causing gene mutation,tumorigenesis,severe inflammation,and obstructive hydrocephalus induced by brain *** of neural or non-neural lineage cells into functional neurons is a promising strategy for the diseases involving neuron loss,which may overcome the above-mentioned disadvantages of neural stem cell *** far,many strategies to transfo rm astrocytes,fibroblasts,microglia,Muller glia,NG2 cells,and other glial cells to mature and functional neurons,or for the conversion between neuronal subtypes have been developed thro ugh the regulation of transcription factors,polypyrimidine tra ct binding protein 1(PTBP1),and small chemical molecules or are based on a combination of several factors and the location in the central nervous ***,some recent papers did not obtain expected results,and discrepancies ***,in this review,we discuss the history of neuronal transdifferentiation,summarize the strategies for neuronal replenishment and conversion from glia,especially astrocytes,and point out that biosafety,new strategies,and the accurate origin of the truly co nverted neurons in vivo should be focused upon in future *** also arises the attention of replenishing the lost neurons from glia by gene therapies such as up-regulation of some transc ription factors or downregulation of PTBP1 or drug interfe rence therapies.

关键词： astrocytes neural stem cells neurodegenerative diseases neuron polypyrimidine tract binding protein 1 repair reprogramming small molecule transcription factor transdifferentiation

Characteristics,origins,and significance of pyrites in deep-water shales

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Science China Earth Sciences 2024年第2期67卷 313-342页

作者： Chao liang Shichao JI Yingchang CAO Keyu liu jing WU Fang HAO National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China School of Geosciences China University of PetroleumQingdao266000China Laboratory for Marine Mineral Resource Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China

As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their *** on previous findings,shale pyrites were divided into three major classes(euhedral pyrites,framboidal pyrites(framboids)and metasomatic pyrites)and six sub-classes in this *** the microscopic scale,each type of pyrite is associated with a different formation *** are formed by burst nucleation in environments with a homogeneous distribution of nutrients while euhedral pyrites are usually formed on pre-existing sites(such as=FeS on the minerals surface)in the heterogeneous *** pyrites formed by the replacement of other ions in accountable material by iron ions and hydrogen sulfide ions in hydrothermal *** morphology and isotope value of pyrite provide information to track the origins of their nutrient and characteristics of sulfur and iron *** addition,the trace element content of pyrite can serve as a proxy for paleo-ocean trace element abundance,indicating changes in atmospheric oxygen ***,pyrite can also serves as an indicator of shale gas reservoirs.

关键词： Shale Pyrite Sulfate reduction reaction Isotope fractionation Pyrite element

Experimental investigation on pyrolysis products and pore structure characteristics of organic-rich shale heated by supercritical carbon dioxide

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Petroleum Science 2024年第4期21卷 2393-2406页

作者： Bai-Shuo liu Chuan-Jin Yao Jia-Long Qi Ya-Qian liu liang Xu jing-Xuan Hou State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) Key Laboratory of Unconventional Oil & Gas Development (China University of Petroleum (East China)) Ministry of Education School of Petroleum Engineering China University of Petroleum (East China)

The efficient pyrolysis and conversion of organic matter in organic-rich shale,as well as the effective recovery of pyrolysis shale oil and gas,play a vital role in alleviating energy *** state of carbon dioxide（CO2） in the pyrolysis environment of shale reservoirs is the supercritical *** unique supercritical fluid properties not only effectively heat organic matter,displace pyrolysis products and change shale pore structure,but also achieve carbon storage to a certain *** samples were made into powder and three sizes of cores,and nitrogen（N2） and supercritical carbon dioxide（ScCO2）pyrolysis experiments were performed at different final pyrolysis *** properties and mineral characteristics of the pyrolysis products were studied based on gas chromatography analysis,Xray diffraction tests,and mass spectrometry ***,the pore structure characteristics at different regions of cores before and after pyrolysis were analyzed using N2adsorption tests to clarify the impact of fracturing degree on the pyrolysis *** results indicate that the optimal pyrolysis temperature of Longkou shale is about 430℃.Compared with N2,the oil yield of ScCO2pyrolysis is *** pyrolysis oil obtained by ScCO2extraction has more intermediate fractions and higher relative molecular *** ScCO2can effectively improve the pore diameter of shale and its effect is better than that of *** micropores are produced in shale after pyrolysis,and the macropores only are generated in ScCO2pyrolysis environments with temperatures greater than 430℃.The pore structure has different development characteristics at different pyrolysis temperatures,which are mainly affected by the pressure holding of volatile matter and products *** to the surface of the core,the pore development effect inside the core is *** the decrease in core size,the pore diameter,specific surface area,and pore volume of cores all increase after pyrolysis.

关键词： Organic-rich shale Supercritical carbon dioxide In-situ pyrolysis Pore structure Core size and region

A Stable Wavelength Operation Ho:YAG Laser with Orthogonally Polarized Pump

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Chinese Physics Letters 2019年第2期36卷 12-14页

作者： jing-liang liu Xin-Yu Chen Rui-Ming Wang Chun-Ting Wu Guang-Yong Jin Jilin Key Laboratory of Solid Laser Technology and Application College of Science Changchun University of Science and Technology

A stable wavelength operation Ho:YAG laser dual-pumped by two orthogonally polarized Tm:YLF lasers is reported. Under the cw operation mode, a laser output power of 24 W is measured. The corresponding opticaloptical conversion efficiency is 44.75% and the slope efficiency is 50.12%. Under the Q-switched operation mode,the output maximum average power is 22.8 W at the re-frequency of 6 kHz. The corresponding optical-optical conversion efficiency and slope efficiency are 42.64% and 48.01%, respectively. The output central wavelength is 2090.73 nm, the linewidth is 0.40 nm, and the beam quality is M^2< 1.6. Moreover, the shift of the output central wavelength is less than 0.01 nm, and the linewidth shift is also less than 0.01 nm.

关键词： YAG length Ho A Stable Wavelength Operation Ho:YAG Laser with Orthogonally Polarized Pump

Wavelength-Locked 878.6 nm In-Band Pumped Intra-Cavity 2.1 μm Optical Parametric Oscillator

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Chinese Physics Letters 2019年第8期36卷 56-59页

作者： Shuang Wu Yong-Ji Yu Yue Li Yu-Heng Wang jing-liang liu Guang-Yong Jin Jilin Key Laboratory of Solid Laser Technology and Application College of Science Changchun University of Science and Technology

We report herein a high-power folded intra-cavity 2.1μm optical parametric oscillator(ICOPO)which is the first example of an ICOPO that utilizes a wavelength-locked 878.6 nm in-band pumped Nd:YVO4 laser as the pump *** thermal effect of PPMgLN crystal and the divergence angle of the incident laser are considered comprehensively to determine the 2128 nm degenerate *** the experiment,the functions of different output coupler transmittances and different repetition rates on the parametric laser output power are studied,*** temperature versus parametric laser output power in an in-band p umped non-wavelength-locked880 nm laser diode(LD)and in a wavelength-locked 878.6 nm LD is compared.A maximum output power of 5.87 W is obtained at the pump power of 56.9 W when the repetition rate is 80 *** corresponding conversion efficiency is 14.55%,with a linewidth of 73.65 nm and pulse width of 3.62 *** wavelength-locked 878.6 nm LD in-band pumping technology can stabilize the 2.1μm laser output power of Nd:YVO4 crystal effectively in the environment of intense temperature change.

关键词： OPO PPMgLN Wavelength-Locked

Carbon cathode with heteroatom doping and ultrahigh surface area enabling enhanced capacitive behavior for potassium-ion hybrid capacitors

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Rare Metals 2024年第5期43卷 2136-2149页

作者： Yan Xiong Ya-Fei Zhang Chun-liu Zhu Lei Yang Huan-Yu liang jing Shi jing-Wei Chen Wei-QianTian Shuai liu Zhi Li jing-Yi Wu Huan-Lei Wang School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 2V4Canada

Potassium-ion hybrid capacitors(PIHCs)are widely regarded as highly promising energy storage devices,due to their exceptional energy density,impressive power density,and abundant potassium ***,restricted by the inherent capacitive storage mechanism,the carbon cathodes possess a much lower specific capacity than battery-type ***,designing high-performance carbon cathodes is extremely urgent for the development of ***,N,O codoped porous carbon(NOPC)was fabricated through the NaCl hard template method and combined KOH/melamine chemical activation technique,displaying the characteristics of abundant N/O content(4.7 at%/16.9 at%),ultrahigh specific surface area(3092 m^(2)g^(-1))and hierarchical pore *** designed NOPC cathode delivers a high specific capacity(164.4 mAh.g^(-1)at 0.05 A.g^(-1))and superior cyclability(95.1%retention ratio at 2 A·g^(-1)over 2500 cycles).Notably,the adjustable ratio of micropores to mesopores facilitates the achievement of the optimal bal-ance between capacity and rate ***,the pseudocapacitance can be further augmented through the incorporation of N/O functional *** expected,the graphite//NOPC based PIHC possesses a high energy density of 113 Wh·kg-at 747 W·kg^(-1)and excellent capacity retention of 84.4% fter 400 cycles at 1.0 A·g^(-1).This work introduces a novel strategy for designing carbon cathodes that enhances the electrochemical performance of PIHCs.

关键词： Template method N/O co-doping High specific surface area Carbon cathode Potassium-ion capacitors