检索结果-南通市图书馆

Effect of BRM S1 expression on proliferation, migration and adhesion of mouse forestomach carcinoma

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2015年第9期8卷 712-717页

作者： Xiu-Li Guo Ya-Jie Wang Pei-Lin Cui Yan-Bin Wang Pi-Xia Liang Ya-Nan Zhang You-Qing Xu Department of Digestive System Beijing Tiantan Hospital Capital Medical University Central Laboratory Beijing Tian Tan Hospital Capital Medical University Department of Laboratory Beijing Tiantan Hospital Capital Medical University

Objective: To discuss the ef ect of BRMS1 on the proliferation, migration and adhesion of mouse forestomach carcinoma(MFC). Methods: The constructed p CMV-myc-BRMS1 recombinant plasmid and blank plasmid were transfected into mouse forestomach carcinoma. MTT method was employed to measure the activity of gastric cancer cell; the scratch assay and Transwell assay to measure the migration and invasion of gastric cancer cell; the adhesion assay to measure the adhesion of gastric cancer cell; while the Western blot assay to measure the expression of The NF-毷B signal pathway, downstream matrix metalloproteinase(MMP-2), MMP-9 and osteopontin and E-cadherin in the gastric cancer cell. Besides, the transplanted animal model of gastric cancer in mice was constructed to measure the size of tumor xenograft. Results: Results of MTT assay showed that, compared with the empty vector control group, the activity of gastric cancer cell was not af ected in the BRMS1 transfection group. The improved expression of BRMS1 could inhibit the adhesion, migration and invasion of gastric cancer cell(Padhesion, migration, invasion and metastasis of MCF gastric cancer cell, which is related to The NF-毷B signal pathway.

关键词： BRMS1 Proliferation Migration adhesion Forestomach carcinoma Mice

A MODEL FOR COMPUTATIONAL INVESTIGATION OF ELASTO-PLASTIC NORMAL AND TANGENTIAL CONTACT CONSIDERING adhesion EFFECT

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2004年第2期20卷 165-171页

作者：李群仰余寿文 Key Lab.of Failure Mechanics MoEDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China

With the rapid development of Micro-Electro-Mechanical System(MEMS),we enter a field in which the surface effects have dominated many of the micro-scale phenomena,and the adhesive contact is one of the focuses.In this paper,a feasible model for finite element computation is presented via a macroscopic and microscopic combination approach,in which the adhesive forces are simulated by some non-linear spring elements considering the softening stage.Two basic problems concerning the adhesion effect were considered;through specific quantitative analysis,the results show a consistency with the current elastic continuum theories of adhesion and a brief investigation into the effects of adhesion on plastic deformation and tangential contact will be carried out as well.

关键词： adhesion adhesive force contact tangential contact

The relation between a microscopic threshold-force model and macroscopic models of adhesion

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2017年第3期33卷 508-515页

作者： Srivatsan Hulikal Kaushik Bhattacharya Nadia Lapusta School of Engineering Brown University Department of Mechanical and Civil Engineering California Institute of Technology

This paper continues our recent work on the relationship between discrete contact interactions at the microscopic scale and continuum contact interactions at the macroscopic scale (Hulikal et al., J. Mech. Phys. Solids 76, 144-161, 2015). The focus of this work is on adhesion. We show that a collection of a large number of discrete elements governed by a threshold-force based model at the microscopic scale collectively gives rise to continuum fracture mechanics at the macroscopic scale. A key step is the introduction of an efficient numerical method that enables the computation of a large number of discrete contacts. Finally, while this work focuses on scaling laws, the methodology introduced in this paper can also be used to study rough-surface adhesion.

关键词： adhesion Threshold-force model Johnson-Kendall-Roberts (JKR) theory Fracture Fast Multipole Method

Modified hyaluronic acid hydrogels with chemical groups that facilitate adhesion to host tissues enhance cartilage regeneration

在线全文

学校读者我要写书评

暂无评论

Bioactive Materials 2021年第6期6卷 1689-1698页

作者： Jiaqing Chen Jiabei Yang Li Wang Xuewei Zhang Boon Chin Heng Dong-An Wang Zigang Ge Department of Biomedical Engineering College of EngineeringPeking UniversityBeijing100871PR China School of Stomatology Peking UniversityBeijing100081PR China Department of Biomedical Engineering College of EngineeringCity University of Hong KongHong Kong SARPR China

Stable integration of hydrogel implants with host tissues is of critical importance to cartilage tissue engineering.Designing and fabricating hydrogels with high adhesive strength,stability and regeneration potential are major challenges to be overcome.This study fabricated injectable adhesive hyaluronic acid(HA)hydrogel modified by aldehyde groups and methacrylate(AHAMA)on the polysaccharide backbone with multiple anchoring mechanisms(amide bond through the dynamic Schiff base reaction,hydrogen bond and physical interpenetration).AHAMA hydrogel exhibited significantly improved durability and stability within a humid environment(at least 7 days),together with higher adhesive strength(43 KPa to skin and 52 KPa to glass),as compared to commercial fibrin glue(nearly 10 KPa)and HAMA hydrogel(nearly 20 KPa).The results showed that AHAMA hydrogel was biocompatible and could be easily and rapidly prepared in situ.In vitro cell culture experiments showed that AHAMA hydrogel could enhance proliferation(1.2-folds after 3 days)and migration(1.5-folds after 12 h)of bone marrow stem cells(BMSCs),as compared to cells cultured in a culture dish.Furthermore,in a rat osteochondral defect model,implanted AHAMA hydrogel significantly promoted integration between neo-cartilage and host tissues,and significantly improved cartilage regeneration(modified O’Driscoll histological scores of 16.0±4.1 and 18.3±4.6 after 4 and 12-weeks of post-implantation in AHAMA groups respectively,12.0±2.7 and 12.2±2.8 respectively in HAMA groups,9.8±2.4 and 11.5±2.1 respectively in untreated groups).Hence,AHAMA hydrogel is a promising adhesive biomaterial for clinical cartilage regeneration and other biomedical applications.

关键词： Cartilage regeneration Hydrogel adhesion Schiff base reaction Hyaluronic acid Aldehyde

Role of interfacial water in adhesion,friction,and wear--A critical review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2021年第1期9卷 1-28页

作者： Lei CHEN Linmao QIAN Tribology Research Institute State Key Laboratory of Traction PowerSouthwest Jiaotong UniversityChengdu 610031China

Surficial water adsorption and interfacial water condensation as natural phenomena that can alter the contact status of the solid interface and tribological performances are crucial in all length scales,i.e.,from earthquakes to skating at the macroscale level and even to micro/nano-electromechanical systems(M/NEMS)at the microscale/nanoscale level.Interfacial water exhibits diverse structure and properties from bulk water because of its further interaction with solid surfaces.In this paper,the evolutions of the molecular configuration of the adsorbed water layer depending on solid surface chemistry(wettability)and structure,environmental conditions(i.e.,relative humidity and temperature),and experimental parameters(i.e.,sliding speed and normal load)and their impacts on tribological performances,such as adhesion,friction,and wear,are systematically reviewed.Based on these factors,interfacial water can increase or reduce adhesion and friction as well as facilitate or suppress the tribochemical wear depending on the water condensation kinetics at the interface as well as the thickness and structure of the involved interfacial water.

关键词： water adsorption water condensation adhesion friction tribochemical wear

Enhanced alumina film adhesion of Hf/Y-doped iron-aluminum alloys during high-temperature oxidation:a new observation

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2019年第9期38卷 877-884页

作者： Dong-Qing Li Li-Xian Zhou Jun Zhan Jing-Chao Wang Jian Gu Jia-Jun Si Department of Transmission and Transformation Engineering Mechanics China Electric Power Research Institute

The cyclic oxidation behavior of Hf/Y-doped B2 FeAl intermetallics at 1373 K was investigated.For an undoped FeAl alloy,premature spallation of the alumina film occurs due to the formation of numerous voids at the film/alloy interface and apparent shrinkage in the film.In contrast to this,doping with either Hf or Y significantly improves the interfacial adhesion between the alumina film and the alloy substrate,particularly with Hf-doping.Microstructural observation in combination with Anger electron spectroscopic analysis suggests that in addition to prohibiting interfacial void formation and alleviating film shrinkage,the addition of Hf in the FeAl alloy could consolidate the film/alloy interface by directly participating in chemical bonding across the interface as a Hf ion.This causes the spallation of alumina film from the equiaxed grains/columnar grains interface rather than the bottom of the film.

关键词： Intermetallics Reactive elements Thermal cycling Alumina film Interfacial adhesion Segregation

An Elastic-plastic adhesion Model for Contacting Fractal Rough Surface and Perfectly Wetted Plane with Meniscus

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2009年第1期22卷 9-14页

作者： PENG Yunfeng GUO Yinbiao Department of Mechanical and Electrical Engineering Xiamen University Xiamen 361005 China

The strong stiction of adjacent surfaces with meniscus is a major design concern in the devices with a micro-sized interface. Today, more and more research works are devoted to understand the adhesion mechanism. This paper concerns the elastic-plastic adhesion of a fractal rough surface contacting with a perfectly wetted rigid plane. The topography of rough surface is modeled with a two-variable Weierstrass-Mandelbrot fractal function. The Laplace pressure is dealt with the Dugdale approximation. Then the adhesion model of the plastically deformed asperities with meniscus can be established with the fractal microcontact model. According to the plastic flow criterion, the elastic-plastic adhesion model of the contacting rough surfaces with meniscus can be solved by combining the Maugis-Dugdale （MD） model and its extension with the Morrow method. The necessity for considering the asperities＇ plastic deformation has been validated by comparing the simulation result of the presented model with that of the elastic adhesion model. The stiction mechanism of rough surfaces with meniscus is also discussed.

关键词： adhesion meniscus Laplace pressure rough surface ffactal function

Nanoparticles Covered Surfaces for Post-functionalization with Aromatic Groups to Obtain Parahydrophobic Surface with High Water adhesion （Petal Effect）

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2017年第3期14卷 468-475页

作者： Guilhem Godeau Marek Dovcik Frederic Guittard Thierry Darmanin Universite Cote d'Azur NICE Lab 1MREDD Pare Valrose 061 O0 Nice France

Numerous exceptional properties can be observed in nature. Among these properties, parahydrophobic feature is of in- terest. This property describes material with high adhesion with water such as rose petals or gecko foot. Such kind of surface presents a real potential for applications in the field of water harvesting systems. In this work, we report a new synthetic strategy to mimic this property. Here, we combine three strategies in one, First, a monomer is electropolymerized in order to form the starting structured surface. Then, nanoparticles are grafted on the surface to increase the structuration and consequently to create the reactive surface. Finally, the grafted surface is post-functionalized （Huisgen reaction） with various aryl alkynes to control the surface chemistry and energy. This strategy allows to reach surfaces with both very high hydrophobic properties （0= 140~） and high water adhesion. This work also includes the surface wettability, roughness and morphology investigation in order to study the impact of the starting monomer structure and post-functionalization on the surface properties.

关键词： conductive polymers nanostructures click chemistry superhydrophobic adhesion

Mucosal adhesion and anti-inflammatory effects of Lactobacillus rhamnosus GG in the human colonic mucosa: A proof-of-concept study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2018年第41期24卷 4652-4662页

作者： Cristiano Pagnini Vito Domenico Corleto Michela Martorelli Claudio Lanini Giancarlo D'Ambra Emilio Di Giulio Gianfranco Delle Fave Department of Digestive and Liver Disease School of Medicine and PsychologyS.Andrea HospitalSapienza University

AIM To investigate the adhesion and anti-inflammatory effects of Lactobacil us rhamnosus GG (LGG) in the colonic mucosa of healthy and ulcerative colitis (UC) patients, both in vivo and ex vivo in an organ culture model.METHODS For the ex vivo experiment, a total of 98 patients (68 UC patients and 30 normal subjects) were included. Endoscopic biopsies were collected and incubated with and without LGG or LGG-conditioned media to evaluate the mucosal adhesion and anti-inflammatory effects [reduction of tumor necrosis factor alpha (TNFα) and interleukin (IL)-17 expression] of the bacteria, and extraction of DNA and RNA for quantification by real-time (RT)-PCR occurred after the incubation. A dose-response study was performed by incubating biopsies at "regular", double and 5 times higher doses of LGG. For the in vivo experiment, a total of 42 patients (20 UC patients and 22 normal controls) were included. Biopsies were taken from the colons of normal subjects who consumed a commercial formulation of LGG for 7 d prior to the colonoscopy,and the adhesion of the bacteria to the colonic mucosa was evaluated by RT-PCR and compared with that of control biopsies from patients who did not consume the formulation. LGG adhesion and TNFα and IL-17 expression were compared between UC patients who consumed a regular or double dose of LGG supplementation prior to colonoscopy.RESULTS In the ex vivo experiment, LGG showed consistent adhesion to the distal and proximal colon in normal subjects and UC patients, with a trend towards higher concentrations in the distal colon, and in UC patients, adhesion was similar in biopsies with active and quiescent inflammation. In addition, bioptic samples from UC patients incubated with LGG conditioned media (CM) showed reduced expression of TNFα and IL-17 compared with the corresponding expression in controls (P adhesion and the anti-inflammatory effects (P < 0.05). In the in vivo experiment, LGG was detectable only in the colon of

关键词： Lactobacillus rhamnosus GG Ulcerative colitis Probiotic adhesion Cytokines