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Strong Adhesion (strong + adhesion)
Selected AbstractsInheritance of the F4ab, F4ac and F4ad E. coli receptors in swine and examination of four candidate genes for F4acRJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 2005P. Python Summary Susceptibility to enterotoxigenic Escherichia coli with fimbriae F4ac is dominantly inherited in the pig. A three-generation pedigree was created to refine the position of F4acR on chromosome 13 comprising 202 pigs: eight parents, 18 F1 and 176 F2 pigs. The 17-point analysis indicates that F4acR lies between Sw207 and S0283. Recombinant offspring specify that the most probable order is Sw207,S0075,F4acR,Sw225,S0283. We observed six phenotypes for the three fimbrial variants F4ab, F4ac and F4ad. The two missing phenotypes F4abR,/F4acR+/F4adR+ and F4abR,/F4acR+/F4adR, indicate that pigs susceptible to F4ac are always susceptible to F4ab. Furthermore, a weak and a strong adhesion of F4ab and F4ad bacteria was observed. The weak receptor F4abR (F4abRw) was present only in pigs devoid of the receptor F4acR (F4abR+/F4acR,). In contrast, in pigs with the phenotype F4abR+/F4acR+, F4ab bacteria adhered to the majority of enterocytes. F4abRw constitutes a frequently observed phenotype whose inheritance is still unclear. Strong adhesion of F4ab and F4ac bacteria is most likely influenced by the same receptor that we name F4bcR. The number of F4ad bacteria that adhered to enterocytes was very variable in the adhesion test. Moreover, expression of F4adR was independent of age. Our segregation analyses indicated a dominant inheritance of F4adR, although the number of susceptible pigs was smaller than expected. We examined four genes as candidates for the F4acR locus: the transferrin receptor gene (TFRC) and three genes members of the glucosyl/galactosyltransferase family (B3GnT5, B3GALT3 and B4GALT4). Comparison of sequences from resistant and homozygous susceptible F4ac pigs did not reveal any causative single nucleotide polymorphism in the four genes. Two silent mutations at the positions 295 (C/T) and 313 (T/C) in B3GALT3 were found. Using the somatic cell hybrid panel, B3GnT5 and B3GALT3 were assigned to the chromosomal region SSC13q23-q41. No mutations were found in the cDNA sequences of these genes associated with the F4acR genotypes. [source] Vascular smooth muscle cell phenotypic modulation in culture is associated with reorganisation of contractile and cytoskeletal proteinsCYTOSKELETON, Issue 3 2001Nathalie F. Worth Abstract Smooth muscle cells (SMC) exhibit a functional plasticity, modulating from the mature phenotype in which the primary function is contraction, to a less differentiated state with increased capacities for motility, protein synthesis, and proliferation. The present study determined, using Western analysis, double-label immunofluorescence and confocal microscopy, whether changes in phenotypic expression of rabbit aortic SMC in culture could be correlated with alterations in expression and distribution of structural proteins. "Contractile" state SMC (days 1 and 3 of primary culture) showed distinct sorting of proteins into subcellular domains, consistent with the theory that the SMC structural machinery is compartmentalised within the cell. Proteins specialised for contraction (,-SM actin, SM-MHC, and calponin) were highly expressed in these cells and concentrated in the upper central region of the cell. Vimentin was confined to the body of the cell, providing support for the contractile apparatus but not co-localising with it. In line with its role in cell attachment and motility, ,-NM actin was localised to the cell periphery and basal cortex. The dense body protein ,-actinin was concentrated at the cell periphery, possibly stabilising both contractile and motile apparatus. Vinculin-containing focal adhesions were well developed, indicating the cells' strong adhesion to substrate. In "synthetic" state SMC (passages 2,3 of culture), there was decreased expression of contractile and adhesion (vinculin) proteins with a concomitant increase in cytoskeletal proteins (,-non-muscle [NM] actin and vimentin). These quantitative changes in structural proteins were associated with dramatic changes in their distribution. The distinct compartmentalisation of structural proteins observed in "contractile" state SMC was no longer obvious, with proteins more evenly distributed throughout the cytoplasm to accommodate altered cell function. Thus, SMC phenotypic modulation involves not only quantitative changes in contractile and cytoskeletal proteins, but also reorganisation of these proteins. Since the cytoskeleton acts as a spatial regulator of intracellular signalling, reorganisation of the cytoskeleton may lead to realignment of signalling molecules, which, in turn, may mediate the changes in function associated with SMC phenotypic modulation. Cell Motil. Cytoskeleton 49:130,145, 2001. © 2001 Wiley-Liss, Inc. [source] Bi-Stable Adhesion of a Surface with a DimpleADVANCED ENGINEERING MATERIALS, Issue 5 2010Robert M. McMeeking In this paper, we propose a new adhesive system of dimpled surfaces. The principle is derived from a contact mechanics model. The material is assumed to be linear elastic and isotropic, and attraction between the surfaces of the half-spaces is modeled via the concept of a specific adhesion energy. It is found that large and small detachments are unstable and will either grow or shrink spontaneously when their sizes are perturbed. It is shown that this phenomenon can lead to a new bi-stable adhesive system in which weak adhesion can be converted to strong adhesion by the application of pressure. [source] Hydrophobins: the protein-amphiphiles of filamentous fungiFEMS MICROBIOLOGY REVIEWS, Issue 5 2005Markus B. Linder Abstract Hydrophobins are surface active proteins produced by filamentous fungi. They have a role in fungal growth as structural components and in the interaction of fungi with their environment. They have, for example, been found to be important for aerial growth, and for the attachment of fungi to solid supports. Hydrophobins also render fungal structures, such as spores, hydrophobic. The biophysical properties of the isolated proteins are remarkable, such as strong adhesion, high surface activity and the formation of various self-assembled structures. The first high resolution three dimensional structure of a hydrophobin, HFBII from Trichoderma reesei, was recently solved. In this review, the properties of hydrophobins are analyzed in light of these new data. Various application possibilities are also discussed. [source] Simple Patterning via Adhesion between a Buffered-Oxide Etchant-Treated PDMS Stamp and a SiO2 Substrate,ADVANCED FUNCTIONAL MATERIALS, Issue 13 2007Y.-K. Kim Abstract A very simple polydimethylsiloxane (PDMS) pattern-transfer method is devised, called buffered-oxide etchant (BOE) printing. The mechanism of pattern transfer is investigated, by considering the strong adhesion between the BOE-treated PDMS and the SiO2 substrate. PDMS patterns from a few micrometers to sub-micrometer size are transferred to the SiO2 substrate by just pressing a stamp that has been immersed in BOE solution for a few minutes. The patterned PDMS layers work as perfect physical and chemical passivation layers in the fabrication of metal electrodes and V2O5 nanowire channels, respectively. Interestingly, a second stamping of the BOE-treated PDMS on the SiO2 substrate pre-patterned with metal as well as PDMS results in a selective transfer of the PDMS patterns only to the bare SiO2. In this way, the fabrication of a device structure consisting of two Au electrodes and V2O5 nanowire network channels is possible; non-ohmic semiconducting I,V characteristics, which can be modeled by serially connected percolation, are observed. [source] Influence of Binding-Site Density in Wet BioadhesionADVANCED MATERIALS, Issue 20 2008Jijun Wang The biomimetic adhesion polymer poly[(dopamine acrylamide)- co -(butylamine acrylamide)] shows strong adhesion even in aqueous environments. With single-molecule atomic force microscopy experiments, we show that the adhesion force does not depend on the density of the functional dopamine groups. [source] Micropatterning Layers by Flame Aerosol Deposition-Annealing,ADVANCED MATERIALS, Issue 16 2008Antonio Tricoli A flame process for in situ synthesis and micropatterned deposition of highly porous, self-assembled, lace-like nanostructured layers of pure or Pt-doped SnO2 is presented. These layers are stabilized in situ by rapid flame annealing that results in transparent cauliflower-like layers with strong adhesion to substrates containing integrated circuitry, while exhibiting high CO sensitivity (f). [source] Adhesion molecule expression by bone marrow CD34-positive cells in aplastic anemia before and after immunosuppressive therapyINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 6 2003K. Kaito Summary Appropriate adhesion between bone marrow stem cells and the marrow microenvironment is necessary for hematopoiesis, since signals that promote maturation or apoptosis are transmitted from stromal cells to stem cells. In aplastic anemia (AA), interferon- , produced by stromal cells has more influence on the pathogenesis of marrow failure than interferon- , produced by lymphocytes. We evaluated the expression of cell adhesion molecules, such as very late antigen-4 (CD49d), and -5 (CD49e) or c-kit receptor (CD117), by CD34-positive bone marrow cells in patients with AA who achieved hematological complete remission after immunosuppressive therapy. Before treatment, CD34-positive cells showed markedly higher expression of CD49d and CD49e than cells from healthy controls, indicating the strong adhesion of stem cells to the bone marrow stroma. Expression of CD49d and CD49e was significantly decreased, reaching normal levels, after hematological recovery. These findings suggest that changes in adhesion molecule expression by stem cells are important in the pathology of AA. [source] Laparoscopic adrenalectomy: Troublesome casesINTERNATIONAL JOURNAL OF UROLOGY, Issue 5 2009Gaku Kawabata Among 143 cases of laparoscopic adrenalectomy carried out from 1993 to the present, 13 patients in whom the surgical manipulation presented problems were examined. Problems occurred due to the condition of the adrenal tumors themselves in six patients, whereas problems occurred due to the operative history in four patients. There were three patients with no operative history but with strong intraperitoneal adhesion. In patients with a history of laparotomy in other fields such as open cholecystectomy, gastrectomy or colostomy, operations were possible in most patients by examining the trocar site preoperatively. Patients with strong adhesion even without a history of surgery could be handled by full separation of the adhesion during surgery. In patients with bleeding in the adrenal tumors, large adrenal tumors, or tumors impacted in the liver, methods such as changing the sequence of separation procedures were required. In patients with a history of renal subcapsular hematomas due to extracorporeal shock wave lithotripsy (ESWL), it was not possible to understand the conditions of adrenal or perinephritic adhesion in preoperative imaging diagnosis, but resection was possible by changing the order of separation procedures and by using optimal instruments and devices. As with any surgery, including open surgeries, it is necessary to obtain knowledge on how to deal with variations in laparoscopic adrenalectomy to assure safe outcomes and to always consider effective methods for coping with unexpected difficulties. [source] Inheritance of the F4ab, F4ac and F4ad E. coli receptors in swine and examination of four candidate genes for F4acRJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 2005P. Python Summary Susceptibility to enterotoxigenic Escherichia coli with fimbriae F4ac is dominantly inherited in the pig. A three-generation pedigree was created to refine the position of F4acR on chromosome 13 comprising 202 pigs: eight parents, 18 F1 and 176 F2 pigs. The 17-point analysis indicates that F4acR lies between Sw207 and S0283. Recombinant offspring specify that the most probable order is Sw207,S0075,F4acR,Sw225,S0283. We observed six phenotypes for the three fimbrial variants F4ab, F4ac and F4ad. The two missing phenotypes F4abR,/F4acR+/F4adR+ and F4abR,/F4acR+/F4adR, indicate that pigs susceptible to F4ac are always susceptible to F4ab. Furthermore, a weak and a strong adhesion of F4ab and F4ad bacteria was observed. The weak receptor F4abR (F4abRw) was present only in pigs devoid of the receptor F4acR (F4abR+/F4acR,). In contrast, in pigs with the phenotype F4abR+/F4acR+, F4ab bacteria adhered to the majority of enterocytes. F4abRw constitutes a frequently observed phenotype whose inheritance is still unclear. Strong adhesion of F4ab and F4ac bacteria is most likely influenced by the same receptor that we name F4bcR. The number of F4ad bacteria that adhered to enterocytes was very variable in the adhesion test. Moreover, expression of F4adR was independent of age. Our segregation analyses indicated a dominant inheritance of F4adR, although the number of susceptible pigs was smaller than expected. We examined four genes as candidates for the F4acR locus: the transferrin receptor gene (TFRC) and three genes members of the glucosyl/galactosyltransferase family (B3GnT5, B3GALT3 and B4GALT4). Comparison of sequences from resistant and homozygous susceptible F4ac pigs did not reveal any causative single nucleotide polymorphism in the four genes. Two silent mutations at the positions 295 (C/T) and 313 (T/C) in B3GALT3 were found. Using the somatic cell hybrid panel, B3GnT5 and B3GALT3 were assigned to the chromosomal region SSC13q23-q41. No mutations were found in the cDNA sequences of these genes associated with the F4acR genotypes. [source] Fabrication of Photonic/Microfluidic Integrated Devices Using an Epoxy PhotoresistMACROMOLECULAR MATERIALS & ENGINEERING, Issue 6 2010Thomas Kowpak Abstract Using a single layer of SU-8 photoresist to fabricate optical waveguide cores and microfluidic channels on Pyrex glass is an ideal way to achieve photonic/microfluidic integration on a single chip. To address the problem of poor bonding, a thin nanoscale intermediate polymer layer was applied to reduce the stress generated from the material processing while maintaining strong adhesion between the patterning polymer layer and Pyrex. It was found that a 186,600,nm thick intermediate layer of a specialty epoxy photoresist effectively served the purpose without deteriorating the optical performance of the involved waveguides. Quality photonic/microfluidic integrated devices with satisfied optical performance were fabricated. [source] Compatibilizing effect of ethylene,propylene,diene grafted maleic anhydride terpolymer on the blend of polyamide 66 and thermal liquid crystalline polymerPOLYMER COMPOSITES, Issue 6 2006Qunfeng Yue Polyamide 66,thermal liquid crystalline polymer (PA66/TLCP) composites containing 10 wt% TLCP was compatibilized by ethylene,propylene,diene-grafted maleic anhydride terpolymer (MAH- g -EPDM). The blending was performed on a twin-screw extrusion, followed by an injection molding. The rheological, dynamic mechanical analysis (DMA), thermal, mechanical properties, as well as the morphology and FTIR spectra, of the blends were investigated and discussed. Rheological, DMA, and FTIR spectra results showed that MAH- g -EPDM is an effective compatibilizer for PA66/TLCP blends. The mechanical test indicated that the tensile strength, tensile elongation, and the bending strength of the blends were improved with the increase of the content of MAH- g -EPDM, which implied that the blends probably have a great frictional shear force, resulting from strong adhesion at the interface between the matrix and the dispersion phase; while the bending modulus was weakened with the increase of MAH- g -EPDM content, which is attributed to the development of the crystalline phase of PA66 hampered by adding MAH- g -EPDM. POLYM. COMPOS., 27:608,613, 2006. © 2006 Society of Plastics Engineers [source] A review on interface modification and characterization of natural fiber reinforced plastic compositesPOLYMER ENGINEERING & SCIENCE, Issue 9 2001Jayamol George An Important aspect with respect to optimal mechanical performance of fiber reinforced composites in general and durability in particular is the optimization of the interfacial bond between fiber and polymer matrix. The quality of the fiber-matrix interface is significant for the application of natural fibers as reinforcement for plastics. Since the fibers and matrices are chemically different, strong adhesion at their interfaces is needed for an effective transfer of stress and bond distribution throughout an Interface. A good compatibilization between cellulose fibers and non-polar matrices is achieved from polymeric chains that will favor entanglements and interdiffiusion with the matrix. This article gives a critical review on the physical and chemical treatment methods that improve the fiber-matrix adhesion and their characterization methods. [source] Starch-based nanocomposites by reactive extrusion processingPOLYMER INTERNATIONAL, Issue 10 2004Sathya B Kalambur Abstract Nanocomposites with unique material properties have been prepared from synthetic plastics and nanosilicates (nanoclay) until now, but not from biopolymers such as starch. The primary challenge in making biopolymeric nanocomposites is to achieve strong adhesion between nanoclay and polymer matrix. For the first time nanocomposites with superior properties have been successfully made from starch-polycaprolactone (PCL) blends in the presence of montmorillonite (MMT) nanoclay. Reactive extrusion results showed that addition of a modified nanoclay at 3 % wt level increased elongation almost fourfold over that of pristine starch,PCL blends. X-ray diffractions results showed dispersion of clay in the polymer matrix. The nanocomposites have better solvent-resistance properties because of resistance to diffusion offered by clay platelets in the polymer matrix. Copyright © 2004 Society of Chemical Industry [source] 111Indium-labelled human gut-derived T cells from healthy subjects with strong in vitro adhesion to MAdCAM-1 show no detectable homing to the gut in vivoCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 1 2004J. KELSEN SUMMARY Integrin ,4,,7 is the principal gut-homing receptor, and it is assumed that expression of this specific integrin directs lymphocytes to the gut in vivo. Adoptive cellular immunotherapy against inflammatory bowel disease (IBD) may depend on the expression of integrin ,4,,7 to accomplish local delivery of intravenously injected regulatory T cells in inflamed gut mucosa. The present study aimed to investigate whether in vitro expanded human T cells from the colonic mucosa maintain integrin expression, show in vitro adhesion and retain in vivo gut-homing properties during cultivation. Whole colonic biopsies from healthy subjects were cultured in the presence of interleukin-2 (IL-2) and IL-4. The integrin expression of the cultured T cells was determined by flow cytometry and in vitro adhesion was assessed in a mucosal addressin cell adhesion molecule 1 (MAdCAM-1) adhesion assay. We studied the homing pattern after autologous infusion of 3 × 108 111Indium (111In)-labelled T cells in five healthy subjects using scintigraphic imaging. The cultured CD4+CD45RO+ gut-derived T cells express higher levels of integrin ,4,,7 than peripheral blood lymphocytes (PBLs) and show strong adhesion to MAdCAM-1 in vitro, even after 111In-labelling. Scintigraphic imaging, however, showed no gut-homing in vivo. After prolonged transit through the lungs, the T cells migrated preferentially to the spleen, liver and bone marrow. In conclusion, it is feasible to infuse autologous T cells cultured from the gut mucosa, which may be of interest in adoptive immunotherapy. Despite high expression of the gut-homing integrin ,4,,7 and adhesion to MAdCAM-1 in vitro, evaluation by 111In-scintigraphy demonstrated no gut-homing in healthy individuals. [source] | ||||||||||||||||||||||||||||