Upon activation with various noncytokine stimuli, polymorphonuclear leukocytes (PMNs) mobilize intracellular sialidase to the plasma membrane, where the sialidase releases sialic acid from the cell surface. This desialylation enhances PMN adherence, spreading, deformability, and motility, functions critical to diapedesis. We now have examined the role of sialidase activity in PMN adhesion to and migration across the endothelium in vivo. A polyclonal antibody prepared against Clostridium perfringens neuraminidase 1) detected surface expression of sialidase on human PMNs stimulated with IL-8 in vitro and on murine PMNs stimulated in vivo, but not on that of unstimulated cells, 2) recognized proteins in human PMN lysates and granule preparations that were not detected by preimmune antibody, 3) inhibited bacterial neuraminidase and human PMN sialidase activities in vitro, and 4) inhibited both pulmonary leukostasis in mice systemically infused with cobra venom factor and intrapulmonary transendothelial migration of PMNs into the bronchoalveolar compartment of mice intranasally challenged with interleukin-8. We conclude that the chemokine interleukin-8, like other PMN agonists, induces the translocation of sialidase to the PMN surface and that surface expression of this sialidase is a prerequisite to PMN recruitment in vivo. The ability of antibodies raised against a prokaryotic neuraminidase to recognize eukaryotic sialidase extends the concept of the neuraminidase superfamily to mammalian enzymes. Inhibition of mobilized endogenous sialidase may provide a novel strategy for limiting the inflammatory response.

The amount of sialic acid on the surface of the neutrophil (PMN) influences its ability to interact with other cells. PMN activation with various stimuli mobilizes intracellular sialidase to the plasma membrane, where it cleaves sialic acid from cell surfaces. Because enhanced PMN adherence, spreading, deformability, and motility each are associated with surface desialylation and are critical to PMN diapedesis, we studied the role of sialic acid on PMN adhesion to and migration across pulmonary vascular endothelial cell (EC) monolayers in vitro. Neuraminidase treatment of either PMN or EC increased adhesion and migration in a dose-dependent manner. Neuraminidase treatment of both PMNs and ECs increased PMN adhesion to EC more than treatment of either PMNs or ECs alone. Moreover, neuraminidase treatment of ECs did not change surface expression of adhesion molecules or release of IL-8 and IL-6. Inhibition of endogenous sialidase by either cross-protective antineuraminidase antibodies (45.5% inhibition) or competitive inhibition with pseudo-substrate (41.2% inhibition) decreased PMN adhesion to ECs; the inhibitable sialidase activity appeared to be associated with activated PMNs. Finally, EC monolayers preincubated with activated PMNs became hyperadhesive for subsequently added resting PMNs, and this hyperadhesive state was mediated through endogenous PMN sialidase activity. Blocking anti-E-selectin, anti-CD54 and anti-CD18 antibodies decreased PMN adhesion to tumor necrosis factor-activated ECs but not to PMN-treated ECs. These data implicate desialylation as a novel mechanism through which PMN-EC adhesion can be regulated independent of de novo protein synthesis or altered adhesion molecule expression. The ability of activated PMNs, through endogenous sialidase activity, to render the EC surface hyperadherent for unstimulated PMNs may provide for rapid amplification of the PMN-mediated host response.

. Protein tyrosine phosphatase activity regulates endothelial cell-cell interactions, the paracellular pathway, and capillary tube stability. Am J Physiol Lung Cell Mol Physiol 285: L63-L75, 2003. First published March 7, 2003 10.1152/ajplung.00423.2002-Protein tyrosine phosphorylation is tightly regulated through the actions of both protein tyrosine kinases and protein tyrosine phosphatases. In this study, we demonstrate that protein tyrosine phosphatase inhibition promotes tyrosine phosphorylation of endothelial cell-cell adherens junction proteins, opens an endothelial paracellular pathway, and increases both transendothelial albumin flux and neutrophil migration. Tyrosine phosphatase inhibition with sodium orthovanadate or phenylarsine oxide induced dose-and time-dependent increases in [14 C]bovine serum albumin flux across postconfluent bovine pulmonary artery endothelial cell monolayers. These increases in albumin flux were coincident with actin reorganization and intercellular gap formation in both postconfluent monolayers and preformed endothelial cell capillary tubes. Vanadate (25 M) increased tyrosine phosphorylation of endothelial cell proteins 12-fold within 1 h. Tyrosine phosphorylated proteins were immunolocalized to the intercellular boundaries, and several were identified as the endothelial cell-cell adherens junction proteins, vascular-endothelial cadherin, and ␤-, ␥-, and p120-catenin as well as platelet endothelial cell adhesion molecule-1. Of note, these tyrosine phosphorylation events were not associated with disassem-

Well‐defined amphiphilic graft copolymer with hydrophobic polysulfone (PSU) backbone and hydrophilic poly(acrylic acid) (PAA) side chains were synthesized and characterized. For this purpose, commercially available PSU was converted to azido‐functionalized polymer (PSU‐N3) by successive chloromethylation and azidation processes. Independently, poly(tert‐butyl acrylate) (PtBA) with an alkyne‐end‐group is obtained by using suitable initiator in atom transfer radical polymerization (ATRP). Then, this polymer was successfully grafted onto PSU‐N3 by click chemistry to yield polysulfone‐graft‐poly(tert‐butyl acrylate), (PSU‐g‐PtBA). Finally, amphiphilic polysulfone‐graft‐poly(acrylic acid), (PSU‐g‐PAA), membranes were obtained by hydrolyzing precursor the PSU‐g‐PtBA membranes in trifluoroacetic acid. The final polymer and intermediates at various stages were characterized by 1H NMR, FTIR, GPC, and SEM analyses. Protein adsorption and eukaryotic and prokaryotic cell adhesion on PSU‐g‐PAA were studied and compared to those of PSU‐g‐PtBA and unmodified PSU. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010

This study indicates that people suffering from the disease did not ask for any professional healthcare or that the healthcare providers could not diagnose these cases.

No abstract

The generation and fabrication of nanoscopic structures are of critical technological importance for future implementations in areas such as nanodevices and nanotechnology, biosensing, bioimaging, cancer targeting, and drug delivery. Applications of carbon nanotubes (CNTs) in biological fields have been impeded by the incapability of their visualization using conventional methods. Therefore, fluorescence labeling of CNTs with various probes under physiological conditions has become a significant issue for their utilization in biological processes. Herein, we demonstrate a facile and additional fluorophore-free approach for cancer cell-imaging and diagnosis by combining multiwalled CNTs with a well-known conjugated polymer, namely, poly(p-phenylene) (PP). In this approach, PP decorated with poly(ethylene glycol) (PEG) was noncovalently (π-π stacking) linked to acid-treated CNTs. The obtained water self-dispersible, stable, and biocompatible f-CNT/PP-g-PEG conjugates were then bioconjugated to estrogen-specific antibody (anti-ER) via -COOH functionalities present on the side-walls of CNTs. The resulting conjugates were used as an efficient fluorescent probe for targeted imaging of estrogen receptor overexpressed cancer cells, such as MCF-7. In vitro studies and fluorescence microscopy data show that these conjugates can specifically bind to MCF-7 cells with high efficiency. The represented results imply that CNT-based materials could easily be fabricated by the described approach and used as an efficient "fluorescent probe" for targeting and imaging, thereby providing many new possibilities for various applications in biomedical sensing and diagnosis.

To date, western Anatolia has been accepted as a non-endemic area for this disease, with only sporadic cases. These non-endemic CCHF cases in Aydin province of the Aegean region should alert other non-endemic regions of the world to be mindful of this disease.