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Abnormal Systemic and Ocular Responses to the Valsalva Manoeuvre in Primary Open-Angle Glaucoma:A Case for Autonomic Failure?

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Current Medical Science 2023年第2期43卷 376-383页

作者： Bin-bin LIU bo-wen ZHAO Fei-peng WU Tian HU Yin ZHAO Hong ZHANG Department of Ophthalmology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective This study aimed to examine the association of primary open-angle glaucoma(POAG)with autonomic dysfunction by assessing the differences in systemic and ocular responses to an autonomic provocation test,the Valsalva manoeuvre(VM),between POAG patients and normal *** Forty POAG and forty control subjects were subjected to the *** and ocular parameters were measured at baseline,phase 2,and phase 4 of the VM(VM2 and VM4),where VM2 and VM4 are sympathetic and parasympathetic nervous activation states,*** rate variability was used to assess the autonomic nervous activity,among which the high-frequency component(HF)and the low-frequency(LF)/HF ratio were used as indices of parasympathetic and sympathetic activation,*** POAG patients demonstrated higher sympathetic activation(LF/HF ratio median:2.17 vs.1.53,P=0.000)than controls at baseline and exhibited attenuated sympathetic and parasympathetic responses(a smaller change in LF/HF and HF values)during the VM than *** VM,the intraocular pressure(IOP),mean blood pressure(MAP),mean ocular perfusion pressure(MOPP),and the Schlemm’s canal area(SCAR)increased from baseline to VM2 and then decreased from VM2 to VM4 in both the POAG and control groups(all Pbove,the fluctuations in IOP,MAP,and MOPP were more pronounced in POAG than in controls(all Pcht)in the POAG group was significantly decreased,while it was unchanged in normal subjects(P=0.258).A regression analysis showed a significant correlation of the baseline LF/HF with IOP change values(ΔIOP)from baseline to VM2 in POAG(R^(2)=0.147,P=0.014).Conclusion Patients with POAG showed more pronounced fluctuations in IOP,MAP,MOPP and cht during the VM than *** reactions could be associated with autonomic dysfunction in POAG.

关键词： primary open-angle glaucoma Valsalva manoeuvre autonomic dysfunction intraocular pressure Schlemm’s canal

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Chitinase 10 controls chitin amounts and organization in the wing cuticle of Drosophila

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Insect Science 2020年第6期27卷 1198-1207页

作者： Wei Dong Ying-Hao Gao Xu-bo Zhang Bernard Moussian Jian-Zhen Zhang Institute of Applied Biology Shanxi UniversityTaiyuanChina College of Life Science Shanxi UniversityTaiyuanChina Interfaculty Institute of Cell Biology University of TubingenTubingenGermany Universite Cote d'Azur CNRSInsermiBVParc ValroseNice CEDEX 2France

Wings are essential for insect fitness.A number of proteins and enzymes have been identified to be involved in wing terminal differentiation,which is characterized by the formation of the wing ***,we addressed the question whether chitinase 10(cht10)may play an important role in chitin organization in the wings of the fruit fly Drosophila ***,we first found that cht10 expression coincides with the expression of the chitin synthase coding gene *** suggests that the respective proteins may cooperate during wing *** tissue-specific RNA interference experiments,we demonstrate that suppression of cht10 causes an excess in chitin amounts in the wing *** organization is severely disrupted in these *** on these data,we hypothesize that cht10 restricts chitin amounts produced by Kkv in order to ensure normal chitin organization and wing cuticle *** addition,we found by scanning electron microscopy that cht10 suppression also affects the cuticle *** turn,cuticle inward permeability is enhanced in cht10 Aess ***,flies with reduced cht 10 function are unable to *** conclusion,cht10 is essential for wing terminal differentiation and function.

关键词： cht10 chitin cuticle Drosophila melanogaster,Kkv wing

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Tough Polyion Complex Hydrogel Films of Natural Polysaccharides

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Chinese Journal of Polymer Science 2017年第10期35卷 1276-1285页

作者： Feng-bo Zhu Hai-chao Yu Wen-xi Lei Ke-feng Ren Jin Qian 吴子良 Qiang Zheng Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Department of Engineering Mechanics Zhejiang University Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

The developments of tough hydrogels in recent years have greatly expanded the applications of hydrogels as structural materials. However, most of the tough hydrogels are made of synthetic polymers. To develop biopolymer-based tough hydrogels has both fundamental and practical significances. Here we report a series of polysaccharides-based tough hydrogel films prepared by polyion complexation and solvent evaporation of chondroitin sulfate（CS） and protonated chitosan（cht） solutions with different weight ratios. The obtained CS/cht gel films with thickness of 40-80 μm and water content of 66 wt%-81 wt% possess excellent mechanical properties, with tensile breaking stress and breaking strain being 0.4-3 MPa and 160%-320%, respectively. We found that in the mixture solutions there are large amounts of excess cht in terms of charges; after swelling the films in water, the acetic acid, which is used to protonate the amino groups of cht, diffuses out of the gel matrix, enhancing the intermolecular interactions between cht molecules and thus improving the mechanical properties of gel films, besides the ionic bonds between CS and cht. Antimicrobial tests also showed that the gel films with low weight ratio of CS to cht, corresponding to the case with excess cht, have evident antimicrobial effect. These CS/cht gel films with good mechanical properties and antimicrobial effect should extend the applications of hydrogels in biomedical fields.

关键词： responsive polymerization methacrylate acrylamide hydrophilic reversible dissipation AMPS toughness swelling

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Insect group II chitinase Ofchtll promotes chitin degradation during larva-pupa molting

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Insect Science 2021年第3期28卷 692-704页

作者： Ming-bo Qu Shao-Peng Sun Yuan-Sheng Liu Xiao-Rui Deng Jun Yang Qing Yang School of Bioengineering Dalian University of TechnologyDalianLiaoningChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection and Shenzhen Agricultural Genome Research InstituteChinese Academy of Agricultural SciencesBeijingChina

The insect group ll chitinase(chtIl,also known as cht10)is a unique chitinasewith multiple catalytic and chitin-binding *** has been proven genetically to be anessential chitinase for ***,chtll's role in chitin degradation during insectdevelopment remains poorly *** this knowledge is the key to fullyunderstanding the chitin degradation system in ***,we investigated the roleof Ofchtll during the molting of Ostrinia furnacalis,a model lepidopteran pest *** was expressed earlier than OfchtI(Ofcht5)and OfChi-h,at both the gene andprotein levels during larva-pupa molting as evidenced by quantitative polymerase chainreaction and western blot analyses.A truncated OfchtII,OfchtII-B4C1,was recombinantlyexpressed in Pichia pastoris cells and purified to *** recombinant Ofchtll-B4C1 loosened compacted chitin particles and produced holes in the cuticle surface asevidenced by scanning electron *** synergized with Ofchtl and OfChi-h whenhydrolyzing insoluble *** findings suggested an important role for chtIl duringinsect molting and also provided a strategy for the coordinatdd degradation of cuticularchitin during insect molting by chtll,chtl and Chi-h.

关键词： chitin chitinase chitin binding degradation multiple module synergy

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Heterologous expression and characterization of two chitinase 5 enzymes from the migratory locust Locusta migratoria

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Insect Science 2016年第3期23卷 406-416页

作者： Ying-Long Li Hui-Fang Song Xue-Yao Zhang Da-Qi Li Ting-Ting Zhang En-bo Ma Jian-Zhen Zhang Research Institute of Applied Biology College of Life Science Shanxi University Taiyuan China

Insect chitinases are involved in degradation of chitin from the exoskeleton or peritrophic metrix ofmidgut. In Locusta migratoria, two duplicated cht5s （Lmcht5-1 and Lmcht5-2） have been shown to have distinct molecular characteristics and biological roles. To explore the protein properties of the two Lmcht5s, we heterologously expressed both enzymes using baculovirus expression system in SF9 cells, and characterized kinetic and carbohydrate-binding properties of purified enzymes. Lmcht5-1 and Lmcht5-2 exhibited similar pH and temperature optimums. Lmcht5-1 has lower Km value for the oligomeric substrate （4MU-（GlcNAe）3）, and higher Km value for the longer substrate （CM-Chitin- RBV） compared with Lmcht5-2. A comparison of amino acids and homology modeling of catalytic domain presented similar TIM barrel structures and differentiated amino acids between two proteins. Lmcht5-1 has a chitin-binding domain （CBD） tightly bound to colloidal chitin, but Lmcht5-2 does not have a CBD for binding to colloidal chitin. Our results suggested both Lmcht5- I and Lmcht5-2, which have the critical glutamate residue in region II of catalytic domain, exhibited chitinolytic activity cleaving both polymeric and oligomeric substrates. Lmcht5-1 had relatively higher activity against the oligomeric substrate, 4MU-（GlcNAc）3, whereas Lmcht5-2 exhibited higher activity toward the longer substrate, CM-Chitin-RBE These findings are helpful for further research to clarit}g their different roles in insect growth and development.

关键词： chitinase 5 enzyme kinetics heterologous expression Locusta migratoria

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Macular choroidal thickness in Chinese preschool children: decrease with axial length but no evident change with age

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International Journal of Ophthalmology(English edition) 2019年第9期12卷 1465-1473页

作者： Xian-Gui He Jun-Jie Deng Yao Yin bo Zhang Shu-Yu Xiong Jian-Feng Zhu Hai-Dong Zou Xun Xu Ling Wang Department of Maternal and Child Health School of Public HealthKey Laboratory of Public Health SafetyMinistry of EducationFudan UniversityShanghai 200032China Department of Preventative Ophthalmology Shanghai Eye Disease Prevention and Treatment CenterShanghai Eye HospitalShanghai 200040China Department of Ophthalmology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai 200080China

AIM: To explore the distribution pattern of macular choroidal thickness(cht) and its association with age as well as refractive status in Chinese ***: School-based, cross-sectional study. A total of 550 healthy preschool children aged 3 to 6 years old from 6 kindergartens were enrolled. Comprehensive ocular examinations, including measurement of visual acuity, axial length, intraocular pressure and slit-lamp examination before cycloplegia, as well as refraction measurement and sweptsource optical coherence tomography(SS-OCT) examination after cycloplegia, were performed. The macular cht in each sector of the ETDRS grid was measured by the builtin software of ***: The mean central cht of the participants was 312±59 μm. The mean axial length and spherical equivalent refraction were 22.36±0.72 mm and 1.51±0.83 D, respectively. Axial length increased with age(Pcht in all sectors among different age groups(all P>0.05). The central cht of 3-4, 5 and 6 years old children was 314±59 μm, 312±60 μm and 312±59 μm, respectively(P=0.920). No difference was observed in cht in most of the sectors between genders. No statistical significant difference was observed among different refractive groups(all P>0.05), though the cht of each sector seemed to be smaller in myopic children. Axial length and weight were the independent factors of central Ch T. Children with longer axial length(β=-21.184, Pcht remains relatively stable with age, while a negative association between cht and axial length existed. This will be helpful to elucidate the characteristics of cht during the early refractive development.

关键词： preschool children choroidal thickness refractive error optical coherence tomography

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广东凉茶作用于大鼠的血清代谢组学研究

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华南理工大学学报（自然科学版） 2012年第12期40卷 145-150页

作者：尤蓉李冰徐振波李琳华南理工大学轻工与食品学院广东广州510640

传统中医理论认为,广东凉茶具有清热祛湿等多种功效.但由于其成分异常复杂,难以利用传统评价手段对其作用机制进行全面分析.文中引入代谢组学的研究策略,即采用稳定性和重复性俱佳的核磁共振技术(NMR)获得大鼠血清样本中代谢物指纹图谱... 详细信息

传统中医理论认为,广东凉茶具有清热祛湿等多种功效.但由于其成分异常复杂,难以利用传统评价手段对其作用机制进行全面分析.文中引入代谢组学的研究策略,即采用稳定性和重复性俱佳的核磁共振技术(NMR)获得大鼠血清样本中代谢物指纹图谱的"全景"数据,然后对其进行多元数据分析,识别差异标志物.结果表明,长期饮用广东凉茶使大鼠体内的脂类代谢、糖代谢及能量代谢发生变化,且其代谢响应呈现阶段性特征.本研究为深入解析广东凉茶的作用机制和建立科学的凉茶评价系统提供了实验依据.

关键词：广东凉茶代谢组学核磁共振技术多元数据分析

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高温透平气热耦合通流设计与分析

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工程热物理学报 2016年第5期37卷 969-974页

作者：巴威李海波顾春伟清华大学热能工程系热科学与动力工程教育部重点实验室北京100084

透平冷却技术的广泛应用带来了冷却透平中主流流动和传热过程的复杂耦合问题。传统透平设计过程中,通常将气动设计与冷却设计分开进行,因而难以充分考虑二者之间的相互影响。本文在某高温轴流透平的初步设计中采用了一种气热耦合的通流... 详细信息

透平冷却技术的广泛应用带来了冷却透平中主流流动和传热过程的复杂耦合问题。传统透平设计过程中,通常将气动设计与冷却设计分开进行,因而难以充分考虑二者之间的相互影响。本文在某高温轴流透平的初步设计中采用了一种气热耦合的通流设计方法,该方法在传统通流计算的基础上引入了冷却计算模型,并以通流计算得到的主流流场参数作为传热计算的边界条件,由此求得透平所需冷气量及主流流场参数。本文采用ANSYS CFX对设计透平进行了性能分析,结果表明该气热耦合通流设计方法可以在透平初步设计阶段提供较大的借鉴意义。

关键词：气热耦合通流方法冷却模型数值计算

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电站用Q390钢焊接温度模拟与组织性能分析

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材料热处理学报 2016年第11期37卷 172-177页

作者：迟露鑫黄灿严博伦高选泽重庆理工大学材料科学与工程学院重庆400050 特种焊接材料与技术重庆市高校工程研究中心(重庆理工大学) 重庆400050 重庆市高校模具技术重点试验室(重庆理工大学) 重庆400050

基于ANSYS有限元对锅炉用Q390钢多道次气体保护焊接温度场进行数值模拟,获得了热循环曲线、峰值温度与组织状态的变化规律,结合SH-CCT曲线,预测了热影响区宽度和组织分布,将结果与相同焊接条件下试验数据对比。结果表明:模拟温度分布与... 详细信息

基于ANSYS有限元对锅炉用Q390钢多道次气体保护焊接温度场进行数值模拟,获得了热循环曲线、峰值温度与组织状态的变化规律,结合SH-CCT曲线,预测了热影响区宽度和组织分布,将结果与相同焊接条件下试验数据对比。结果表明:模拟温度分布与实测数据吻合良好;模拟热影响区宽度为3.3 mm,实测位置的峰值温度为1189.54℃,冷却后得到贝氏体和马氏体混合组织;采用药芯焊丝cht711的焊缝为铁素体、贝氏体和珠光体组织,热影响区以贝氏体组织为主;拉伸断裂位置在母材,断口呈杯锥形的韧窝断裂,其力学指标满足工程要求。

关键词： Q390B钢热循环曲线数值模拟组织性能

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考虑涡轮传热性能的气动设计耦合计算方法研究

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推进技术 2018年第11期39卷 2463-2471页

作者：刘维温风波罗磊崔涛王松涛哈尔滨工业大学能源科学与工程学院黑龙江哈尔滨150001

为了在涡轮叶片气动型线设计过程中同时提高气动效率并保证传热性能,提出了一种基于一维管道网络法和三维CFD的耦合计算方法,分别采用管网/三维耦合计算方法和全三维耦合计算方法对MARK-II冷却叶片多个工况进行计算,两种数值计算方法计... 详细信息

为了在涡轮叶片气动型线设计过程中同时提高气动效率并保证传热性能,提出了一种基于一维管道网络法和三维CFD的耦合计算方法,分别采用管网/三维耦合计算方法和全三维耦合计算方法对MARK-II冷却叶片多个工况进行计算,两种数值计算方法计算结果与实验数据交叉对比,以验证本文计算方法可行性。计算结果表明,两种数值计算得到的叶片型面压力、温度、换热系数和实验值都比较吻合,但管网/三维耦合计算得到的壁面温度相比全三维耦合计算结果整体略微偏低,最大偏差不超过3.89%。基于管网/三维耦合计算方法对某航空发动机涡轮第二级动叶叶片型线优化设计,气动效率提高0.34%,壁面平均温度几乎没有变化。

关键词：涡轮管网气热耦合优化耦合计算

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