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Role of C-type natriuretic peptide in the function of normal human sperm

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Asian Journal of Andrology 2016年第1期18卷 80-84页

作者： Hui Xia Yao Chen ke-jia wu Hu Zhao Cheng-Liang Xiong Dong-Hui Huang Family Planning Research Institute Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China People's Hospital of Luoshan County Xinyang 464200 China Department of Human Anatomy Tongji Medical College Hua Zhong University of Science and Technology Wuhan 430030 China

C-type natriuretic peptide （CNP） is a newly discovered type of local regulatory factor that mediates its biological effects through the specific, membrane-bound natriuretic peptide receptor-B （NPR-B）. Recent studies have established that CNP is closely related to male reproductive function. The aims of this study were to determine the distribution of CNP/NPR-B in human ejaculated spermatozoa through different methods （such as immunolocalization, real time polymerase chain reaction and Western Blot）, and then to evaluate the influence of CNP on sperm function in vitro, such as motility and acrosome reaction. Human semen samples were collected from consenting donors who met the criteria of the World Health Organization for normozoospermia. Our results show that the specific receptor NPR-B of CNP is localized in the acrosomal region of the head and the membrane of the front-end tail of the sperm, and there is no signal of CNP in human sperm. Compared with the control, CNP can induce a significant dose-dependent increase in spermatozoa motility and acrosome reaction. In summary, CNP/NPR-B can affect sperm motility and acrosome reaction, thus regulating the reproductive function of males. CNP may be a new key factor in regulating sperm function.

关键词： acrosome reaction C-type natriuretic peptide natriuretic peptide receptor-B sperm motility

Large-scale fabrication of field-effect transistors based on solution-grown organic single crystals

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Science Bulletin 2015年第12期60卷 1122-1127,I0003页

作者： Shuang Liu jia-ke wu Cong-Cheng Fan Guo-Biao Xue Hong-Zheng Chen Huolin L. Xin Han-Ying Li Ministry of Education key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and EngineeringZhejiang University Hangzhou 310027 China Center for Functional Nanomaterials Brookhaven National Laboratory New York NY 11973 USA

A simple solution processing method was de- veloped to grow large-scale well-aligned single crystals in- cluding 6,13-bis（triisopropylsilylethynyl）pentacene （TIPS- pentacene）, anthracene, tetracene, perylene, C6o and tetra- cyanoquinodimethane. As pinned by a solid needle, a droplet of semiconductor solution dried into single-crystal arrays on a 1 cm×2 cm substrate. TIPS-pentacene was used to demonstrate the fabrication of hundreds of field- effect transistors （FETs） with the hole mobility as high as 6.46 cm^2 V^-1.s^-1. As such, this work provides a high- throughput, yet efficient approach for statistical examination on the FET performance of organic single crystals.

关键词： Organic single-crystal transistors Large scale High mobility Solution process

Understanding the cooperative effects in the catalysis of homodimeric fluoroacetate dehalogenase

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Science China Chemistry 2024年第7期67卷 2382-2391页

作者： ke-Wei Chen jia-Nan Chen Jun Zhang Chao Wang Tian-Yu Sun Yun-Dong wu key Laboratory of Computational Chemistry and Drug Design State Key Laboratory of Chemical OncogenomicSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Changping Laboratory Beijing 102200China

Fluoroacetate dehalogenases(FAcD),a homodimeric enzyme,catalyzes the conversion of fluoroacetic acid to glycolic acid(GoA).It has been proved that the enzyme has a half-of-the-site ***,its catalytic(C)subunit converts the first substrate to a covalent intermediate;then,the non-catalytic(NC)subunit binds a second substrate and promotes the conversion of the intermediate in the C subunit into the final *** the release of the product,the C subunit becomes the NC subunit,and the previous NC subunit becomes the C *** elucidate the detailed mechanism behind this cooperative catalysis,we have conducted microsecond-scale MD simulations along the reaction *** simulations indicate that the substrate in the NC subunit induces W185 and Y141 adopting an open conformation in the C *** opening of W185(C)facilitates the entry of catalytic water,enhancing the catalytic activity for product formation,while the opening of Y141(C)creates an unfavorable environment for product binding,promoting its *** interaction network analysis reveals that the substrate in the NC subunit can induce conformational changes through a conserved water chain at the interface.

关键词： enzyme catalysis molecular dynamics cooperative effect pre-reaction state

Solution-grown aligned crystals of diketopyrrolopyrroles(DPP)-based small molecules:Rough surfaces and relatively low charge mobility

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Chinese Chemical Letters 2016年第4期27卷 523-526页

作者： Zhuo-Ting Huang Cong-Cheng Fan Guo-Biao Xue jia-ke wu Shuang Liu Huan-Bin Li Hong-Zheng Chen Han-Ying Li MOE key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and Engineering Zhejiang University

Field-effect transistors（FETs） of three diketopyrrolopyrroles（DPP）-based small molecules, 3,6-bis（5-phenylthiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolopyrrole-1,4-dione（PDPPP）, 3,6-bis（5-（4-fluorophenyl）thiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolo pyrrole-1,4-dione（FPDPPPF） and 3,6-bis（5-（4-n-butylphenyl）thiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolo pyrrole-1,4-dione（Bu PDPPPBu）, have been studied in this work. Well aligned crystals of the three molecules were grown from para-xylene by droplet-pinned crystallization method. FETs based on these aligned crystals exhibit a hole mobility up to0.19 cm^2 V 1s 1and electron mobility up to 0.008 cm^2 V 1s 1. The achieved hole mobility is of the same order of magnitude as reported highest hole mobility for DPP-based small molecules, but it is much lower than that of the high-performance DPP-based polymers. The relative low mobility is mainly attributed to the rough crystal surfaces with steps and, thus, non-smooth charge transport channels at the interfaces between the crystals and the dielectrics. This work has implications for understanding the low charge mobility of DPP-based small molecules.

关键词： Diketopyrrolopyrrole Crystals Solution processing Organic field-effect transistors Morphology

Molecular Evolution of Protein Sequences and Codon Usage in Monkeypox Viruses

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 89-97页

作者： ke-jia Shan Changcheng wu Xiaolu Tang Roujian Lu Yaling Hu Wenjie Tan jian Lu State key Laboratory of Protein and Plant Gene Research Center for BioinformaticsSchool of Life SciencesPeking UniversityBeijing 100871China Sinovac Biotech Ltd. Beijing 100085China NHC key Laboratory of Biosafety National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 100052China

The monkeypox virus(mpox virus,MPXV)epidemic in 2022 has posed a significant public health ***,the evolutionary principles of MPXV remain largely ***,we examined the evolutionary patterns of protein sequences and codon usage in *** first demonstrated the signal of positive selection in OPG027,specifically in the CladeⅠlineage of ***,we discovered accelerated protein sequence evolution over time in the variants responsible for the 2022 ***,we showed strong epistasis between amino acid substitutions located in different *** codon adaptation index(CAI)analysis revealed that MPXV genes tended to use more non-preferred codons compared to human genes,and the CAI decreased over time and diverged between clades,with CladeⅠ>Ⅱa andⅡb-A>Ⅱ*** the decrease in fatality rate among the three groups aligned with the CAI pattern,it remains unclear whether this correlation was coincidental or if the deoptimization of codon usage in MPXV led to a reduction in fatality *** study sheds new light on the mechanisms that govern the evolution of MPXV in human populations.

关键词： Mpox virus Positive selection OPG027 Accelerated evolution Codon usage bias

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： He-xiang wu jia Qu Lin-zhi wu key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China School of Civil Engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

The Method of Polynomial Particular Solutions for Solving Nonlinear Poisson-Type Equations

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Acta Mechanica Solida Sinica 2024年第1期37卷 155-165页

作者： Zhile jia Yanhua Cao Xiaoran wu School of Sciences East China Jiaotong UniversityNanchang 330013China

In this paper,the method of polynomial particular solutions is used to solve nonlinear Poisson-type partial differential equations in one,two,and three *** condition number of the coefficient matrix is reduced through the implementation of multiple scale technique,ultimately yielding a stable numerical *** methodological process can be divided into two main parts:first,identifying the corresponding polynomial particular solutions for the linear differential operator terms in the governing equations,and second,employing these polynomial particular solutions as basis function to iteratively solve the remaining nonlinear terms within the governing ***,we investigate the potential improvement in numerical accuracy for equations with singularities in the analytical solution by shifting the computational domain a certain *** experiments are conducted to assess both the accuracy and stability of the proposed method.A comparison of the obtained results with those produced by other numerical methods demonstrates the accuracy,stability,and efficiency of the proposed method in handling nonlinear Poisson-type partial differential equations.

关键词： Nonlinear equation Singularity Polynomial particular solutions Poisson type

Chimeric Monkey Born Alive with a High Contribution of Donor Cells

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Neuroscience Bulletin 2024年第6期40卷 849-851页

作者： jia Huang Jun wu Department of Molecular Biology University of Texas Southwestern Medical CenterDallasTX75390USA Hamon Center for Regenerative Science and Medicine University of Texas Southwestern Medical CenterDallasTX75390USA Cecil H.and Ida Green Center for Reproductive Biology Sciences University of Texas Southwestern Medical CenterDallasTX75390USA

Chimeras,which consist of cells from different individuals or different species,represent an important tool in biological *** in the early twentieth century,studies on chimeras have been focusing on understanding fundamental genetic and cellular developmental *** the advances in genetic engineering and embryonic stem cell(ESC)technology,chimeras have become an important tool for the generation of transgenic animals.

关键词： mechanisms advances developmental

Glial progenitor heterogeneity and plasticity in the adult spinal cord

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Neural Regeneration Research 2024年第12期19卷 2567-2568页

作者： Haichao Wei jia Qian wu Department of Neurosurgery McGovern Medical SchoolThe University of Texas Health Science Center at HoustonHoustonTXUSA Center for Stem Cell and Regenerative Medicine UT Brown Foundation Institute of Molecular MedicineHoustonTXUSA MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences HoustonTXUSA

Glial progenitor cells were reported to have the capacity to generate various types of cells in both the central nervous system(CNS)and peripheral nervous *** progenitor cells can respond to diverse environmental signals and transform into distinct populations,each serving specific ***,the adult spinal cord hosts various populations of glial progenitors,a region integral to the central nervous *** development,glial progenitors express glial fibrillary acidic protein(GFAP;Dimou and Gotz,2014).However,the specific identities of GFAP-expressing progenitors in the adult spinal cord were not thoroughly investigated.

关键词： functions plasticity thoroughly