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Andrew H Lichtman - One of the best experts on this subject based on the ideXlab platform.
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p selectin and vascular cell adhesion molecule 1 mediate rolling and arrest respectively of cd4 t lymphocytes on tumor necrosis factor alpha activated vascular endothelium under flow
Journal of Experimental Medicine, 1995Co-Authors: Francis W Luscinskas, Han Ding, Andrew H LichtmanAbstract:This report examines the adhesive interactions of human CD4+ T lymphocytes with tumor necrosis factor alpha-activated human endothelial cell monolayers in an in vitro model that mimics microcirculatory flow conditions. Resting CD4+ T cell interactions with activated endothelium consisted of Initial Attachment followed by rolling, stable arrest, and then spreading and transendothelial migration. P-selectin, but not E-, or L-selectin, mediated most of this Initial contact and rolling, whereas beta 1-integrins (alpha 4 beta 1), interacting with endothelial-expressed vascular cell adhesion molecule 1, participated in rolling and mediated stable arrest. In contrast, beta 2-integrins were primarily involved in spreading and transmigration. These findings highlight an important role for P-selectin and suggest discrete functions for beta 1- and beta 2-integrins during lymphocyte recruitment to sites of immune-mediated inflammation.
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p selectin and vascular cell adhesion molecule 1 mediate rolling and arrest respectively of cd4 t lymphocytes on tumor necrosis factor α activated vascular endothelium under flow
Journal of Experimental Medicine, 1995Co-Authors: Francis W Luscinskas, Han Ding, Andrew H LichtmanAbstract:Summary This report examines the adhesive interactions of human CD4 + T lymphocytes with tumor necrosis factor a-activated human endothelial cell monolayers in an in vitro model that mimics microcirculatory flow conditions. Resting CD4 + T cell interactions with activated endothelium consisted of Initial Attachment followed by rolling, stable arrest, and then spreading and transendothelial migration. P-selectin, but not E-, or L-selectin, mediated most of this Initial contact and rolling, whereas Brintegrins (ot4fll), interacting with endothelial-expressed vascular cell adhesion molecule 1, participated in rolling and mediated stable arrest. In contrast, fl2-integrins were primarily involved in spreading and transmigration. These findings highlight an important role for P-selectin and suggest discrete functions for fir and fl2-integrins during lymphocyte recruitment to sites of immune-mediated inflammation.
Francis W Luscinskas - One of the best experts on this subject based on the ideXlab platform.
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L- and P-selectins, but not CD49d (VLA-4) integrins, mediate monocyte Initial Attachment to TNF-alpha-activated vascular endothelium under flow in vitro.
Journal of immunology (Baltimore Md. : 1950), 1996Co-Authors: Francis W Luscinskas, Thomas F Tedder, Han Ding, P Tan, Dale A. Cumming, Mary E. GerritsenAbstract:Monocyte adhesion to the vascular endothelium is a pivotal step during their egress to tissues at sites of inflammation and immune reactions, and during atherogenesis. In this study, an in vitro flow model and blocking mAb were used to define the role of adhesion molecules in monocyte interactions with activated HUVEC under flow conditions. By videomicroscopy, freely flowing monocytes abruptly halted (Initial Attachment) on 6-h TNF-alpha-activated HUVEC under flow via L- and P-selectin, whereas E-selectin was not involved. CD49d/CD29 integrin (VLA-4), which can mediate Initial Attachment of certain T cells to VCAM-1 under flow, did not support monocyte Initial Attachment. Once Initially attached, a small number of monocytes began rolling at 9 microns/s through a mechanism involving L-selectin, as well as CD49d and CD11/CD18 integrins, while the remaining monocytes became firmly adherent, or released to the flow stream. Monocyte stable arrest and subsequent transendothelial migration occurred rapidly and efficiently through either CD49d or CD18 integrin adhesion pathways. Transendothelial passage was also dependent on PECAM-1 (CD31). These data reveal monocytes Initially attach to activated endothelium via an L-selectin-dependent mechanism, with a smaller contribution from P-selectin and no contribution by CD49d. Subsequent monocyte rolling, arrest, and transmigration require overlapping functions between multiple members of the selectin, integrin, and Ig gene families.
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p selectin and vascular cell adhesion molecule 1 mediate rolling and arrest respectively of cd4 t lymphocytes on tumor necrosis factor alpha activated vascular endothelium under flow
Journal of Experimental Medicine, 1995Co-Authors: Francis W Luscinskas, Han Ding, Andrew H LichtmanAbstract:This report examines the adhesive interactions of human CD4+ T lymphocytes with tumor necrosis factor alpha-activated human endothelial cell monolayers in an in vitro model that mimics microcirculatory flow conditions. Resting CD4+ T cell interactions with activated endothelium consisted of Initial Attachment followed by rolling, stable arrest, and then spreading and transendothelial migration. P-selectin, but not E-, or L-selectin, mediated most of this Initial contact and rolling, whereas beta 1-integrins (alpha 4 beta 1), interacting with endothelial-expressed vascular cell adhesion molecule 1, participated in rolling and mediated stable arrest. In contrast, beta 2-integrins were primarily involved in spreading and transmigration. These findings highlight an important role for P-selectin and suggest discrete functions for beta 1- and beta 2-integrins during lymphocyte recruitment to sites of immune-mediated inflammation.
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p selectin and vascular cell adhesion molecule 1 mediate rolling and arrest respectively of cd4 t lymphocytes on tumor necrosis factor α activated vascular endothelium under flow
Journal of Experimental Medicine, 1995Co-Authors: Francis W Luscinskas, Han Ding, Andrew H LichtmanAbstract:Summary This report examines the adhesive interactions of human CD4 + T lymphocytes with tumor necrosis factor a-activated human endothelial cell monolayers in an in vitro model that mimics microcirculatory flow conditions. Resting CD4 + T cell interactions with activated endothelium consisted of Initial Attachment followed by rolling, stable arrest, and then spreading and transendothelial migration. P-selectin, but not E-, or L-selectin, mediated most of this Initial contact and rolling, whereas Brintegrins (ot4fll), interacting with endothelial-expressed vascular cell adhesion molecule 1, participated in rolling and mediated stable arrest. In contrast, fl2-integrins were primarily involved in spreading and transmigration. These findings highlight an important role for P-selectin and suggest discrete functions for fir and fl2-integrins during lymphocyte recruitment to sites of immune-mediated inflammation.
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monocyte rolling arrest and spreading on il 4 activated vascular endothelium under flow is mediated via sequential action of l selectin beta 1 integrins and beta 2 integrins
Journal of Cell Biology, 1994Co-Authors: Francis W Luscinskas, Geoffrey S Kansas, Hart Ding, Pilaf Pizcueta, Boris E Schleiffenbaum, Thomas E Tedder, Michael A GimbroneAbstract:Leukocyte interactions with vascular endothelium at sites of inflammation can be dynamically regulated by activation-dependent adhesion molecules. Current models, primarily based on studies with polymorphonuclear leukocytes, suggest the involvement of multiple members of the selectin, integrin, and immunoglobulin gene families, sequentially, in the process of Initial Attachment (rolling), stable adhesion (arrest), spreading and ultimate diapedesis. In the current study, IL-4-activated human umbilical vein endothelium, which selectively expresses VCAM-1 and an L-selectin ligand but not E-selectin, and appropriate function blocking monoclonal antibodies, were used to study monocyte-endothelial interactions in an in vitro model that mimics microcirculatory flow conditions. In this system, L-selectin mediates monocyte rolling and also facilitates alpha 4 beta 1-integrin-dependent arrest, whereas beta 2-integrins are required for spreading of firmly attached monocytes on the endothelial cell surface but not their arrest. These findings provide the first in vitro evidence for human monocyte rolling on cytokine-activated endothelium, and suggest a sequential requirement for both beta 1- and beta 2-integrin-dependent adhesive mechanisms in monocyte-endothelial interactions.
Scott A Wade - One of the best experts on this subject based on the ideXlab platform.
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inhibition or acceleration bacterial test media can determine the course of microbiologically influenced corrosion
Corrosion Science, 2014Co-Authors: M A Javed, Sally L. Mcarthur, Paul R Stoddart, Enzo A Palombo, Scott A WadeAbstract:The objective of this study was to determine the effect of different test media on the Initial Attachment of Escherichia coli and subsequent corrosion of carbon steel coupons. Nutrient broth (NB) and minimal media (MM) with different carbon sources and phosphate concentrations were used. The Initial bacterial Attachment to the coupons increased with time in all of the studied media. Longer term immersion studies showed accelerated corrosion of steel coupons in all inoculated MM, whereas corrosion inhibition was observed in inoculated NB. The results showed that the test medium can play a critical role in determining the outcome of microbiologically influenced corrosion tests.
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the effect of metal microstructure on the Initial Attachment of escherichia coli to 1010 carbon steel
Biofouling, 2013Co-Authors: M A Javed, Sally L. Mcarthur, Paul R Stoddart, Scott A WadeAbstract:Metallurgical features have been shown to play an important role in the Attachment of microorganisms to metal surfaces. In the present study, the influence of the microstructure of as-received (AR) and heat-treated (HT) 1010 carbon steel on the Initial Attachment of bacteria was investigated. Heat treatment was carried out with the aim of increasing the grain size of the carbon steel coupons. Mirror-polished carbon steel coupons were immersed in a minimal medium inoculated with Escherichia coli (ATCC 25922) to investigate the early (15, 30 and 60 min) and relatively longer-term (4 h) stages of bacterial Attachment. The results showed preferential colonisation of bacteria on the grain boundaries of the steel coupons. The bacterial Attachment to AR steel coupons was relatively uniform compared to the HT steel coupons where an increased number of localised aggregates of bacteria were found. Quantitative analysis showed that the ratio of the total number of isolated (ie single) bacteria to the number of bacte...
Moshe Herzberg - One of the best experts on this subject based on the ideXlab platform.
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side effects of antiscalants on biofouling of reverse osmosis membranes in brackish water desalination
Journal of Membrane Science, 2015Co-Authors: Amer Sweity, Sarit Bason, Tesfalem Rezene Zere, Inbal David, Yoram Oren, Zeev Ronen, Moshe HerzbergAbstract:In this study, we investigated the contribution of antiscalants to biofouling of reverse osmosis (RO) membranes in brackish water desalination process. Both the physico-chemical effects of the antiscalants on the Initial Attachment of bacterial cells to RO membrane surfaces, as well as their nutritional contribution to biofilm growth were analyzed. A bacterial deposition experiment on ESPA-2 RO membrane was conducted using Pseudomonas fluorescens, and the two polyphosphonate- and polyacrylate-based antiscalants. Both the model bacterium and the ESPA-2 RO membranes were treated with feed brackish water with and without antiscalants. The nutritional contribution of these antiscalants to biofilm growth was investigated by growing biofilms in packed-bed biofilm reactors in the presence and absence of the antiscalants. In the presence of both antiscalants, biofilm development was enhanced in comparison to the control. Eventually, the impact of the antiscalant-induced biofilm growth on the performance of RO membranes was investigated in a crossflow RO filtration unit under typical brackish water desalination conditions. Significant membrane biofouling was detected in the presence of the antiscalants compared to the case where no antiscalant was used, accompanied by higher flux decline and salt passage. RO membrane modules were also utilized in an industrial and pilot desalination plants to test the effect of the polyacrylate-based antiscalant. Similar behavior was observed on both scales of membrane operation, with polyacrylate inducing biofilm growth. We assert that the two types of antiscalant induce biofilm formation on RO membrane surfaces through two different mechanisms: while polyacrylates increase bacterial Initial Attachment by altering membrane physico-chemical properties, mainly increasing membrane hydrophobicity, polyphosphonates increase biofilm growth under phosphorous limiting conditions by providing the cells with the phosphorous they lack. Thus, the selection of the type and dosage of antiscalant should take into account the associated contribution to membrane biofouling propensity.
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side effects of antiscalants on biofouling of reverse osmosis membranes in brackish water desalination
Journal of Membrane Science, 2015Co-Authors: Amer Sweity, Sarit Bason, Tesfalem Rezene Zere, Inbal David, Yoram Oren, Zeev Ronen, Moshe HerzbergAbstract:In this study, we investigated the contribution of antiscalants to biofouling of reverse osmosis (RO) membranes in brackish water desalination process. Both the physico-chemical effects of the antiscalants on the Initial Attachment of bacterial cells to RO membrane surfaces, as well as their nutritional contribution to biofilm growth were analyzed. A bacterial deposition experiment on ESPA-2 RO membrane was conducted using Pseudomonas fluorescens, and the two polyphosphonate- and polyacrylate-based antiscalants. Both the model bacterium and the ESPA-2 RO membranes were treated with feed brackish water with and without antiscalants. The nutritional contribution of these antiscalants to biofilm growth was investigated by growing biofilms in packed-bed biofilm reactors in the presence and absence of the antiscalants. In the presence of both antiscalants, biofilm development was enhanced in comparison to the control. Eventually, the impact of the antiscalant-induced biofilm growth on the performance of RO membranes was investigated in a crossflow RO filtration unit under typical brackish water desalination conditions. Significant membrane biofouling was detected in the presence of the antiscalants compared to the case where no antiscalant was used, accompanied by higher flux decline and salt passage. RO membrane modules were also utilized in an industrial and pilot desalination plants to test the effect of the polyacrylate-based antiscalant. Similar behavior was observed on both scales of membrane operation, with polyacrylate inducing biofilm growth. We assert that the two types of antiscalant induce biofilm formation on RO membrane surfaces through two different mechanisms: while polyacrylates increase bacterial Initial Attachment by altering membrane physico-chemical properties, mainly increasing membrane hydrophobicity, polyphosphonates increase biofilm growth under phosphorous limiting conditions by providing the cells with the phosphorous they lack. Thus, the selection of the type and dosage of antiscalant should take into account the associated contribution to membrane biofouling propensity.
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glycosphingolipids enhance bacterial Attachment and fouling of nanofiltration membranes
Environmental Science and Technology Letters, 2015Co-Authors: Moshe Herzberg, Robert Haas, Jenia Gutman, Nathaniel Charles Wardrip, Kazuyoshi Kawahara, Wolfgang Uhl, Christopher J ArnuschAbstract:Biofouling is a ubiquitous problem in many places in society and technology, especially in reverse osmosis or nanofiltration (NF) processes. Initial stages in the development of the biofilm include Attachment of bacteria to the surface, where bacterial outer membrane components such as biopolymers, lipids, and proteins play important roles. Here we show that the glycosphingolipid (GSL) unique to Sphingomonas species is a key player in the Initial Attachment of bacteria to NF membranes whereas lipopolysaccharide (LPS), the major glycolipid in many Gram-negative species, is less significant. GSL and LPS were deposited on an NF membrane with subsequent bacterial culture injection in a three-dimensionally printed microfluidic flow cell. Flux, rejection, and pressure changes showed that GSL caused permanent membrane fouling. This study underlines the significance of Sphingomonas for the Initial Attachment of bacteria to membranes. A deeper understanding and identification of key components in the biofouling pr...
Masao Yoshinari - One of the best experts on this subject based on the ideXlab platform.
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influence of surface wettability on competitive protein adsorption and Initial Attachment of osteoblasts
Biomedical Materials, 2009Co-Authors: Jianhua Wei, Toshio Igarashi, Naoto Okumori, Takayasu Igarashi, Takashi Maetani, Baolin Liu, Masao YoshinariAbstract:This study investigated the influence of surface wettability on competitive protein adsorption and the Initial Attachment of osteoblasts. A thin-film coating of hexamethyldisiloxane (HMDSO) and subsequent O2-plasma treatment was carried out on substrates with a mirror surface in order to create a wide range of wettabilities. The adsorption behavior of fibronectin (Fn) and albumin (Alb) in both individual and competitive mode, and the Initial Attachment of mouse osteoblastic cells (MC3T3-E1) over a wide range of wettabilities were investigated. The contact angle of HMDSO coatings without O2-plasma treatment against double-distilled water was more than 100°, whereas it dramatically decreased after the O2-plasma treatment to almost 0°, resulting in super-hydrophilicity. Individually, Fn adsorption showed a biphasic inclination, whereas Alb showed greater adsorption to hydrophobic surfaces. In the competitive mode, in a solution containing both Fn and Alb, Fn showed greater adsorption on hydrophilic surfaces, whereas Alb predominantly adsorbed on hydrophobic surfaces. The Initial Attachment of osteoblastic cells increased with an increase in surface wettability, in particular, on a super-hydrophilic surface, which correlated well with Fn adsorption in the competitive mode. These results suggest that Fn adsorption may be responsible for increasing cell adhesion on hydrophilic surfaces in a body fluid or culture media under physiological conditions.
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the Initial Attachment and subsequent behavior of osteoblastic cells and oral epithelial cells on titanium
Bio-medical Materials and Engineering, 2004Co-Authors: Tetsuya Goto, Masao Yoshinari, Shigeru Kobayashi, Teruo TanakaAbstract:: The interaction between implant materials and bone cells or oral epithelial (OE) cells contributes to the clinical success of dental implants. The functional activity of cells in contact with an implant is determined by its surface properties. Before cells attach, extracellular matrix (ECM) in the serum deposits on the substrate; rounded cells then attach and spread upon it. Cells form focal adhesions and polarize, then start to migrate or proliferate to form colonies. Comparison of the Attachment and behavior of osteoblastic cells on titanium (Ti) and hydroxyapatite (HA) revealed that more cells attached on HA and that these spread more rapidly than on Ti. In contrast, cells did not form good stress fibers or vinculin-positive focal adhesions on HA, whereas the cells on Ti possessed well-defined and polarized stress fibers. The Initial Attachment of OE cells to Ti was inferior to that on polystyrene culture dish or glass, and the OE cell migration area, indicated by the deposition of LN5, was smaller on Ti than on the other materials. This review summarizes data on the Attachment and behavior of osteoblastic cells and OE cells on biomaterials, which may suggest future improvements in surface properties.
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a study of the Initial Attachment and subsequent behavior of rat oral epithelial cells cultured on titanium
Journal of Periodontology, 2002Co-Authors: Masaru Shiraiwa, Tetsuya Goto, Masao Yoshinari, Kiyoshi Koyano, Teruo TanakaAbstract:Background: The seal between an implant and the oral epithelium is an important factor for successful implant therapy. The purpose of this study was to evaluate the Initial Attachment and subsequent behavior of rat oral epithelial (OE) cells on pure titanium (Ti) used for dental implants. Methods: OE cells derived from 4-day-old rats were cultured on Ti, polystyrene culture dishes, and glass coverslips. The number of attached cells, cell areas, number of colonies, and proliferation rates were measured. Additionally, immunostaining of vinculin and laminin-5 (LN5) was performed, and LN5- immunoreactive areas were measured. Results: After 24 hours of culture, there were fewer cells attached to the Ti than to the polystyrene dishes or glass coverslips, and the area of cells was greater on the polystyrene than on the Ti or glass. OE cells reached their maximum proliferation rate after 48 hours of culture on the polystyrene and glass, and after 72 hours on Ti. LN5 was deposited behind cells as they migrated, an...
