Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The initial step in extravasation of neutrophils (polymorphonuclear leukocytes [PMNs]) to the extravascular space is adherence to the endothelium. We examined the effect of oxidants on this process by treating human endothelial cells with H2O2, t-butylhydroperoxide, or menadione. This resulted in a surface adhesive for PMN between 1 and 4 h after exposure. The oxidants needed to be present only for a brief period at the initiation of the assay. Adhesion was an endothelial cell-dependent process that did not require an active response from the PMN. The adhesive molecule was not platelet-activating factor, which mediates PMN adherence when endothelial cells are briefly exposed to higher concentrations of H2O2 (Lewis, M. S., R. E. Whatley, P. Cain, T. M. McIntyre, S. M. Prescott, and G. A. Zimmerman. 1988. J. Clin. Invest. 82:2045-2055), nor was it ELAM-1, an adhesive glycoprotein induced by cytokines. Oxidant-induced adhesion did not require protein synthesis, was inhibited by antioxidants, and, when peroxides were the oxidants, was inhibited by intracellular iron chelators. Granule membrane protein-140 (GMP-140) is a membrane-associated glycoprotein that can be translocated from its intracellular storage pool to the surface of endothelial cells where it acts as a ligand for PMN adhesion (Geng, J.-G., M. P. Bevilacqua, K. L. Moore, T. M. McIntyre, S. M. Prescott, J. M. Kim, G. A. Bliss, G. A. Zimmerman, and R. P. McEver. 1990. Nature (Lond). 343:757-760). We found that endothelial cells exposed to oxidants expressed GMP-140 on their surface, and that an mAb against GMP-140 or solubilized GMP-140 completely blocked PMN adherence to oxidant-treated endothelial cells. Thus, exposure of endothelial cells to oxygen radicals induces the prolonged expression of GMP-140 on the cell surface, which results in enhanced PMN adherence.
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PMID:Oxygen radicals induce human endothelial cells to express GMP-140 and bind neutrophils. 170 76

Adhesion to epithelial respiratory cells, iron acquisition, and production of K1 polysaccharide capsules have been proposed as potential virulence factors of avian Escherichia coli. These factors were studied by inoculating groups of axenic or specific-pathogen-free (SPF) chickens intratracheally with O2 E. coli strains after previous challenge with a wild strain of infectious bronchitis virus (IBV). In all experiments, the association between IBV and an E. coli strain endowed with the three virulence factors previously mentioned resulted in the most severe pathological effects, as measured by mortality, weight gains, lesions, and reisolation of E. coli from internal organs. An E. coli strain devoid of virulence factors was able only to induce mild pathological effects restricted to the respiratory tract when combined with IBV. Both E. coli strains were more invasive in axenic chickens than in SPF chickens. These results confirm the probable involvement of the three factors studied in the pathogenic properties of avian E. coli. This model can be used to assess the role of virulence factors, by comparing pairs of positive and negative isogenic strains.
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PMID:Comparative infectivity for axenic and specific-pathogen-free chickens of O2 Escherichia coli strains with or without virulence factors. 252 66

The adhesion of cells of Salmonella typhimurium to albite, biotite, felspar, magnetite and quartz was correlated to the presence of fimbriae and degree of hydrophobicity and charge of the bacterial surface. It was found that the presence of fimbriae resulted in a higher degree of adhesion compared to adhesion of nonfimbriated cells. The significance of the physico-chemical characteristics of fimbriae was shown by a direct linearity between high hydrophobicity of fimbriated cells and degree of adhesion to the mineral particles. Fimbriated cells exhibited higher negative as well as positive surface charge as compared to nonfimbriated cells. Adhesion to several of the minerals was shown to be independent of the extent of negative charges on the bacterial surfaces. A high degree of adhesion to biotite, possibly due to a combination of characteristics of the particles, was not related to either bacterial fimbriation or a physico-chemical characteristic of the bacterial surface. The results of the nonspecific adhesion observed are discussed in terms of available binding sites and distribution of physico-chemical characteristics on the bacterial cell surface structures.
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PMID:Fimbriae mediated nonspecific adhesion of Salmonella typhimurium to mineral particles. 286 57

Deferoxamine is a potent chelator of ferric iron. Past studies have shown that deferoxamine interferes with acute inflammatory tissue injury in a number of animal models. In cell culture, it inhibits neutrophil-medicated killing of endothelial cells. Both the animal model and cell culture data are thought to reflect the capacity of deferoxamine to interfere with the superoxide anion- and and ferric iron-dependent reduction of hydrogen peroxide to the hydroxyl radical (Fenton Reaction). The present study describes a second mechanism by which deferoxamine may interfere with the acute inflammatory response. Here it is shown that deferoxamine has the capacity to inhibit neutrophil adhesion to lung epithelial cells and vascular endothelial cells. Adhesion of phorbol ester-stimulated neutrophils to both cell types is reduced by 70-80%. The inhibitory effects are reversible and are overcome when ferric iron is present along with deferoxamine in a 2:1 molar ratio. Concentrations of deferoxamine that prevent neutrophil adhesion also prevent neutrophil-mediated killing of the same target cells. In contrast, deferoxamine does not significantly inhibit activation-induced up-regulation of neutrophil surface adhesion structures (CD11b/CD18) and does not prevent binding of a monoclonal antibody that recognizes beta 2 integrins in the high-affinity state. Release of proteolytic enzymes from activated cells is also not significantly inhibited by deferoxamine. Taken together, these data indicate that deferoxamine modulates neutrophil adhesive functions associated with the activated state. The ability of deferoxamine to interfere with neutrophil binding to target cells may contribute to its anti-inflammatory activity.
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PMID:Deferoxamine interferes with adhesive functions of activated human neutrophils. 879 50

Invasive Escherichia coli strains of certain serotypes invade by the same mechanism as the Shigella sp. It has been proposed that invasion of epithelial cells by EPEC strains may also occur; this is a previously overlooked property. In the present study E. coli strains isolated from patients with diarrhoea or ulcerative colitis, lacking the inv plasmid mediating classical invasion, but hybridizing with probes for different adhesins, were analyzed for their ability to invade HeLa and Caco-2 cells. The majority of strains invaded Caco-2 cells to a higher extent than HeLa cells. Adhesion to Caco-2 cells was a prerequisite for subsequent invasion of the cells but EAF, eae, EAgg and other known virulence factors were not sufficient to mediate invasion. In 8/9 E. coli strains invasion was enhanced after growth under iron restriction. Growth during anaerobic conditions did not influence subsequent invasion by E. coli strains whereas 6/9 strains had their invasive ability significantly decreased after growth in the presence of 1% glucose. The invasive process was inhibited by mannose but not by lactose, fucose or galactose. Our data indicate that strains of E. coli may invade Caco-2 cells by novel mechanisms which require adhesion to the cells but which differ from those of Salmonella sp., Yersinia sp., Shigella sp. and classical enteroinvasive E. coli.
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PMID:Invasion of tissue culture cells by diarrhoeagenic strains of Escherichia coli which lack the enteroinvasive inv gene. 880 71

Shewanella alga BrY adhesion to hydrous ferric oxide, goethite, and hematite was examined. Adhesion to each oxide followed the Langmuir adsorption model. No correlation between adhesion and Fe(III) oxide surface area or crystallinity was observed. Zeta potential measurements suggested that electrostatic interactions do not influence S. alga BrY adhesion to these minerals. Cell adhesion does not appear to explain the recalcitrance of crystalline Fe(III) oxides to bacterial reduction.
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PMID:Adhesion of the dissimilatory Fe(III)-reducing bacterium Shewanella alga BrY to crystalline Fe(III) oxides. 1127 Jun 46

Adhesion problems during tablet manufacturing have been observed to be dependent on many formulation and process factors including the run time on the tablet press. Consequently, problems due to sticking may only become apparent towards the end of the development process when a prolonged run on the tablet press is attempted for the first time. It would be beneficial to predict in a relative sense if a formulation or new chemical entity has the potential for adhesion problems early in the development process. It was hypothesized that favorable intermolecular interaction between the drug molecules and the punch face is the first step or criterion in the adhesion process. Therefore, the rank order of adhesion during tablet compression should follow the rank order of these energies of interaction. The adhesion phenomenon was investigated using molecular simulations and contact mode atomic force microscopy (AFM). Three model compounds were chosen from a family of "profen" compounds. Silicon nitride AFM tips were modified by coating a 20-nm iron layer on the surfaces by sputter coating. Profen flat surfaces were made by melting and recrystallization. The modified AFM probe and each profen surface were immersed in the corresponding profen saturated water during force measurements using AFM. The work of adhesion between iron and ibuprofen, ketoprofen, and flurbiprofen in vacuum were determined to be -184.1, -2469.3, -17.3 mJ. m(-2), respectively. The rank order of the work of adhesion between iron and profen compounds decreased in the order: ketoprofen > ibuprofen > flurbiprofen. The rank order of interaction between the drug molecules and the iron superlattice as predicted by molecular simulation using Cerius(2) is in agreement with the AFM measurements. It has been demonstrated that Atomic Force Microscopy is a powerful tool in studying the adhesion phenomena between organic drug compounds and metal surface. The study has provided insight into the adhesion problems occurring during tablet compression and a direction for continued study.
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PMID:Modeling of adhesion in tablet compression--I. Atomic force microscopy and molecular simulation. 1266 Oct 65

Adhesion to host cells and tissues is important for several steps in the pathogenesis of disseminated Candida albicans infections. Although such adhesion is evident in vivo and for C. albicans grown in vitro in complex medium, some adhesive activities are absent when cultures are grown in defined media. However, addition of hemoglobin to defined media restores binding and adhesion to several host proteins. This activity of hemoglobin is independent of iron acquisition and is mediated by a cell surface hemoglobin receptor. In addition to regulating expression of adhesion receptors, hemoglobin rapidly induces expression of several genes. One of these, a heme oxygenase, allows the pathogen to utilize exogenous heme or hemoglobin to acquire iron and to produce the cytoprotective molecules alpha-biliverdin and carbon monoxide. The specific recognition of and responses to hemoglobin demonstrate a unique adaptation of C. albicans to be both a commensal and an opportunistic pathogen in humans.
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PMID:Sensing the host environment: recognition of hemoglobin by the pathogenic yeast Candida albicans. 1515 65

We developed a scheme of consecutive replacement of complex components of a known Brucella medium containing peptones and blood with simple analogs and created a synthetic medium for Helicobacter pylori culturing. H. pylori cells require hemic iron for their growth; an appreciable increment in biomass was ensured by hemoglobin, but not simpler hemocontaining compounds (hemin and cytochrome C). Glutamine (20 g/liter) was used as the main nitrogen-containing component, and other amino acids were added in trace amounts. Adhesion was provided by adding agarose gel (0.1%) also promoting the increase in biomass. The proposed medium of a certain chemical composition differs from the known foreign analogs by the presence of hemocontaining component (hemoglobin), short period of exponential growth, and appreciable accumulation of cell protein.
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PMID:Creation of a new synthetic medium for culturing Helicobacter pylori. 1622 54

Bacterial adhesion to mineral surfaces plays an important role not only in bacterial survival in natural ecosystems, but also in mining industry applications. Selective adhesion was investigated with Thiobacillus ferrooxidans by using four minerals, pyrite, quartz, chalcopyrite, and galena. Escherichia coli was used as a control bacterium. Contact angles were used as indicators of hydrophobicity, which was an important factor in the interaction between minerals and bacteria. The contact angle of E. coli in a 0.5% sodium chloride solution was 31 degrees , and the contact angle of T. ferrooxidans in a pH 2.0 sulfuric acid solution was 23 degrees . E. coli tended to adhere to more hydrophobic minerals by hydrophobic interaction, while T. ferrooxidans selectively adhered to iron-containing minerals, such as pyrite and chalcopyrite. Ferrous ion inhibited the selective adhesion of T. ferrooxidans to pyrite competitively, while ferric ion scarcely inhibited such adhesion. When selective adhesion was quenched by ferrous ion completely, adhesion of T. ferrooxidans was controlled by hydrophilic interactions. Adhesion of E. coli to pyrite exhibited a liner relationship on langmuir isotherm plots, but adhesion of T. ferrooxidans did not. T. ferrooxidans recognized the reduced iron in minerals and selectively adhered to pyrite and chalcopyrite by a strong interaction other than the physical interaction.
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PMID:Selective Adhesion of Thiobacillus ferrooxidans to Pyrite. 1634 6


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