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Journal of Materials Science & Technology 2024年第3期170卷 246-254页

作者： Ze pu Wang WenHong Ruan MinZhi rong MingQiu Zhang Key Laboratory for Polymeric Composite and Functional Materials of MOE GD HPPC LabIGCMESchool of ChemistrySun Yat-Sen UniversityGuangzhou 510275China

To tackle the challenge of producing highly filled polymer composites using the traditional injection molding technique,which is characterized by the fairly high melt viscosity that makes mold filling difficult,the authors propose a solution based on dynamic covalent chemistry.As demonstrated by the proof-of-concept experiments,the 4-arm starshaped polycaprolactone(PCL)oligomers and microcrystalline cel-lulose(MCC)are crosslinked by the reversible Diels-Alder(DA)bonds.The flowability of the compounds greatly decreases due to the dissociation of the intercomponent DA bonds at the retro-reaction tempera-ture,and the networked architecture is reconstructed during cooling as a result of the forward DA reaction.Consequently,the high-loading MCC fillers are well distributed in the matrix and covalently bonded to the nearby PCL,forming a striking contrast to the control in which linear PCL acts as the matrix.The DA bonds crosslinked biodegradable PCL composites exhibit decent mechanical strength(20.7 MPa)even at the MCC fraction of 65 wt%,which is superior to those(5-12.2 MPa)of the highly filled PCL composites(with filler contents of 50-63.8 wt%)reported so far.The proposed approach has sufficient expansibility for the fabrication of the highly filled polymer composites constructed by other types of matrix and fillers.

关键词： Polymer composites Microcrystalline cellulose Polycaprolactone Injection molding Dynamic reversible chemistry

Protein crystallization with DNA templates

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Particuology 2024年第3期86卷 262-268页

作者： Bo Zhang Jia Yu Zhe pu Wenhui Guo Ruoqi Yang Yu Wen Zhijiang rong Hui Wang Xiaoli Wu Bo Wang Hongyan Sun School of Environment and Resources Taiyuan University of Science and TechnologyTaiyuan030024China School of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024China

Protein crystallization plays a significant role in three-dimensional structural analysis and protein pu-rification.It is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization systems.DNA is biologically compatible and artificially designable polymer,which is easy to extract.In this study,single-and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and catalase.In-fluence of DNA,single-stranded DNA with 10,20,40 bases and double-stranded DNA with 10,20,40 base pairs,were investigated.The success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates added.Double-stranded DNA led to higher nucleation rate than that with single-stranded DNA.The promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA templates.Crystal number and crystallization rate was enhanced with addition of long double-stranded DNA templates.All the results confirm that DNA is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

关键词： DNA Polymer Additive Protein Crystallization

TCERG1L hypermethylation is a risk factor of diabetic retinopathy in Chinese children with type 1 diabetes

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 537-544页

作者： Yu Qian Ying Xiao Qiu-rong Lin Zhao-Yu Xiang Li-pu Cui Jia-Qi Sun Si-Cong Li Xin-Ran Qin Hai-Dong Zou Chen-Hao Yang Pei-Yao Jin Department of Ophthalmology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai First People’s HospitalShanghai 200080China Shanghai Eye Diseases Prevention&Treatment Center Shanghai Eye HospitalShanghai 200040China National Clinical Research Center for Eye Diseases Shanghai Clinical Research Center for Eye DiseasesShanghai Key Clinical SpecialtyShanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai Engineering Center for Precise Diagnosis and Treatment of Eye DiseasesShanghai 200080China Department of Ophthalmology Children’s Hospital of Fudan UniversityShanghai 201102China

●AIM:To identify the differential methylation sites(DMS)and their according genes associated with diabetic retinopathy(DR)development in type 1 diabetes(T1DM)children.●METHODS:This study consists of two surveys.A total of 40 T1DM children was included in the first survey.Because no participant has DR,retina thinning was used as a surrogate indicator for DR.The lowest 25%participants with the thinnest macular retinal thickness were included into the case group,and the others were controls.The DNA methylation status was assessed by the Illumina methylation 850K array BeadChip assay,and compared between the case and control groups.Four DMS with a potential role in diabetes were identified.The second survey included 27 T1DM children,among which four had DR.The methylation patterns of the four DMS identified by 850K were compared between participants with and without DR by pyrosequencing.●RESULTS:In the first survey,the 850K array revealed 751 sites significantly and differentially methylated in the case group comparing with the controls(|Δβ|>0.1 and Adj.P0.05)between participants with and without DR.●CONCLUSION:The hypermethylation of the TCERG1L gene is a risk factor for DR development in Chinese children with T1DM.

关键词： DNA methylation 850K array pyrosequencing diabetic retinopathy type 1 diabetes children

Topological reorganization and functional alteration of distinct genomic components in gallbladder cancer

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Frontiers of Medicine 2024年第1期18卷 109-127页

作者： Guoqiang Li Peng pu Mengqiao Pan Xiaoling Weng Shimei Qiu Yiming Li Sk Jahir Abbas Lu Zou Ke Liu Zheng Wang Ziyu Shao Lin Jiang Wenguang Wu Yun Liu rong Shao Fatao Liu Yingbin Liu Department of Biliary-Pancreatic Surgery Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai200127China State Key Laboratory of Oncogenes and Related Genes Shanghai Cancer InstituteShanghai200127China Shanghai Key Laboratory of Biliary Tract Disease Shanghai200082China Department of Health Science and Engineering University of Shanghai for Science and TechnologyShanghai200082China Shanghai Tenth People’s Hospital of Tongji University Shanghai200072China Department of General Surgery Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai200082China Department of Pharmacology Shanghai Jiao Tong University School of MedicineShanghai200025China

Altered three-dimensional architecture of chromatin influences various genomic regulators and subsequent gene expression in human cancer.However,knowledge of the topological rearrangement of genomic hierarchical layers in cancer is largely limited.Here,by taking advantage of in situ Hi-C,RNA-sequencing,and chromatin immunoprecipitation sequencing(ChIP-seq),we investigated structural reorganization and functional changes in chromosomal compartments,topologically associated domains(TADs),and CCCTC binding factor(CTCF)-mediated loops in gallbladder cancer(GBC)tissues and cell lines.We observed that the chromosomal compartment A/B switch was correlated with CTCF binding levels and gene expression changes.Increased inter-TAD interactions with weaker TAD boundaries were identified in cancer cell lines relative to normal controls.Furthermore,the chromatin short loops and cancer unique loops associated with chromatin remodeling and epithelial–mesenchymal transition activation were enriched in cancer compared with their control counterparts.Cancer-specific enhancer–promoter loops,which contain multiple transcription factor binding motifs,acted as a central element to regulate aberrant gene expression.Depletion of individual enhancers in each loop anchor that connects with promoters led to the inhibition of their corresponding gene expressions.Collectively,our data offer the landscape of hierarchical layers of cancer genome and functional alterations that contribute to the development of GBC.

关键词： 3D genome cancer TADs loop gene regulation

Euphorstranoids A and B,two highly rearranged ingenane diterpenoids from Euphorbia stracheyi:structural elucidation,chemical transformation,and lipid-lowering activity

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Organic Chemistry Frontiers 2022年第3期9卷 775-780页

作者： Fang-Yu Yuan Yue-Hua Pan Ai-Ping Yin Wei Li Dong Huang Xue-Long Yan Shu-Qi Wu Gui-Hua Tang rong pu Sheng Yin School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhouGuangdong 510006People’s Republic of China Department of Clinical Laboratory the Third People’s Hospital of DongguanDongguan 523326People’s Republic of China

Euphorstranoids A(1)and B(2),two highly rearranged ingenane diterpenoids with an unusual 5/6/7/3 carbon ring system,were isolated from Euphorbia stracheyi.Their structures were determined by a combination of spectral,chemical,and X-ray diffraction methods.The plausible biosynthetic pathway of 1 and 2 was proposed and chemically mimicked.Compounds 1 and 2 significantly inhibited the triglyceride(TG)level in 3T3-L1 adipocytes via retarding cell adipogenesis at the early stage.

关键词： methods chemical elucidation

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超协调元

工程力学 2024年第S1期41卷 7-14页

作者：傅向荣王钰赵阳陈璞孙树立中国农业大学土木工程系北京100083 北京大学力学与工程科学系北京100871

该文提出一类超协调的单元理论。不同于在普通协调元中采用的线位移协调插值格式,超协调元的单元插值函数首先引入转角自由度等线位移导数的高阶协调假设,并通过积分推导,进而获得超协调的线位移模型。基于超协调元理论,该文构造了一类... 详细信息

该文提出一类超协调的单元理论。不同于在普通协调元中采用的线位移协调插值格式,超协调元的单元插值函数首先引入转角自由度等线位移导数的高阶协调假设,并通过积分推导,进而获得超协调的线位移模型。基于超协调元理论,该文构造了一类新型的三结点三角形平板壳元SCT。数值算例表明:与其他类型单元相比,基于超协调元理论的单元具有计算精度高和计算效率好的优势。该文所提出单元理论构造简单,超协调元理论可以成为构造高性能数值算法的一种新的通用理论。

关键词：超协调理论壳单元转角自由度有限单元法高阶分片检验

黏多糖贮积症Ⅰ型和Ⅱ型患儿耳鼻喉科表现的特点分析

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临床耳鼻咽喉头颈外科杂志 2024年第3期38卷 221-224,229页

作者：白鑫茹刘嵘冯顺乔普建谷庆隆北京协和医学院研究生院北京100730 首都儿科研究所附属儿童医院

目的分析黏多糖贮积症(mucopolysaccharidosis,MPS)Ⅰ型和Ⅱ型患儿临床表现的特点,以提高耳鼻喉科医生对该病的认识。方法回顾性分析55例MPSⅠ型和Ⅱ型患儿的相关临床资料,探讨MPS在耳鼻喉科的临床表现。结果40例(72.72%)的MPS患者在病... 详细信息

目的分析黏多糖贮积症(mucopolysaccharidosis,MPS)Ⅰ型和Ⅱ型患儿临床表现的特点,以提高耳鼻喉科医生对该病的认识。方法回顾性分析55例MPSⅠ型和Ⅱ型患儿的相关临床资料,探讨MPS在耳鼻喉科的临床表现。结果40例(72.72%)的MPS患者在病程中均至少出现了一种耳鼻喉科症状,其中95%的患者在确诊MPS前出现耳鼻喉科症状;上气道阻塞为最常见的耳鼻喉科症状(34例,85.00%),反复上呼吸道感染次之(23例,57.50%),最后为听力下降(11例,27.50%);26例患者至少接受过1次外科手术,其中15例(57.69%)接受过耳鼻喉科手术,这些患者均在确诊前接受耳鼻喉科手术。最常见的耳鼻喉科手术是腺样体切除术。结论MPS患者早期临床表现不典型,但耳鼻喉科症状出现早期且普遍,提高耳鼻喉科医生对该病的认识对MPS预后有着积极的意义。

关键词：黏多糖贮积症临床表现上气道阻塞反复呼吸道感染听力下降

富含支化精氨酸的两亲性阳离子脂质肽体内外mRNA基因递送能力及安全性评价

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药学学报 2024年第4期59卷 1079-1086页

作者：王一醇蒲艺瑶毕群杰宋相容金蓉蓉聂宇四川大学国家生物医学材料工程技术研究中心/四川大学生物医学工程学院四川成都610064 四川大学生物治疗全国重点实验室四川成都610041

mRNA基因治疗因其可扩展、修饰,不需要进入细胞核及不整合宿主遗传基因等优势而备受关注。在基因治疗中,将mRNA安全有效地递送到细胞内对于基因治疗的成功至关重要。本研究基于前期设计合成的富含支化精氨酸的两亲性阳离子脂质肽(dendri... 详细信息

mRNA基因治疗因其可扩展、修饰,不需要进入细胞核及不整合宿主遗传基因等优势而备受关注。在基因治疗中,将mRNA安全有效地递送到细胞内对于基因治疗的成功至关重要。本研究基于前期设计合成的富含支化精氨酸的两亲性阳离子脂质肽(dendritic arginine&disulfide bond-containing cationic lipopeptide,RLS)基因载体在斑马鱼体内成功实现比商品化试剂Lipofectamine 2000高1.5倍的mRNA转染效果,并通过体外细胞毒性和斑马鱼体内生物安全性研究证实其具有良好的生物安全性。首先,通过核磁共振氢谱(1H NMR)及飞行时间质谱(MALDI-TOF)对阳离子脂质肽的化学成分进行表征。通过动态光散射粒度分析仪(DLS)测试的粒径和电位结果显示,在氮磷(N/P)比为20时,RLS与mRNA复合组装体形成平均粒径约220 nm、表面ζ电位约+21 mV的均匀纳米粒子。体外基因转染中,RLS在人胚肾293细胞(HEK293)和大鼠间充质干细胞(MSC)中的转染效率较Lipofectamine 2000分别提高1.2和3倍。此外,将RLS显微注射至斑马鱼胚胎后,通过评价生存率、孵化率和致畸率等指标,进一步证实了其在体内良好的安全性。综上所述,该富含支化精氨酸的两亲性阳离子脂质肽RLS具有优良的mRNA递送性能和安全性。

关键词：支化精氨酸两亲性阳离子脂质肽基因载体 mRNA递送斑马鱼

家庭亲密度与适应性对大学生生命意义感的影响:积极心理资本的中介作用

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科教文汇 2024年第5期 185-188页

作者：蒲蓉内江师范学院四川内江641100

采用问卷对300名大学生进行调查,探究家庭亲密度与适应性和生命意义感的关系,以及积极心理资本在其中的中介作用。结果显示:男生积极心理资本得分显著高于女生;独生子女家庭亲密度与适应性得分显著高于非独生子女;常住城镇的大学生家庭... 详细信息

采用问卷对300名大学生进行调查,探究家庭亲密度与适应性和生命意义感的关系,以及积极心理资本在其中的中介作用。结果显示:男生积极心理资本得分显著高于女生;独生子女家庭亲密度与适应性得分显著高于非独生子女;常住城镇的大学生家庭亲密度与适应性、生命意义感得分显著高于常住农村的学生;家庭亲密度与适应性可以直接预测大学生的生命意义感,积极心理资本在其中起中介作用。

关键词：家庭亲密度与适应性生命意义感积极心理资本

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试析正当防卫制度的法律适用

北京政法职业学院学报 2024年第2期 32-37页

作者：孙嵘孙瀑西北政法大学山东省济南市人民检察院法律政策研究室

最高人民法院、最高人民检察院、公安部印发的《关于依法适用正当防卫制度的指导意见》对保护防卫人的合法利益作出了诸多规范与阐释,对于正确适用正当防卫制度、激活正当防卫条款亦作出了积极探索。“正当防卫”是普通人对自身的保护... 详细信息

最高人民法院、最高人民检察院、公安部印发的《关于依法适用正当防卫制度的指导意见》对保护防卫人的合法利益作出了诸多规范与阐释,对于正确适用正当防卫制度、激活正当防卫条款亦作出了积极探索。“正当防卫”是普通人对自身的保护与对恶势力的反抗,但其更应该被合理规制,在成为正当的自力救济权的同时又不被滥用。文章尝试梳理新时期正当防卫制度,结合近期最高人民法院、最高人民检察院发布的指导案例,继续厘清正当防卫制度的具体适用,明晰合法权益的充分保护原则,以维护社会公平正义。

关键词：正当防卫紧迫性防卫权本位司法良知