6 results match your criteria: "National Institutes of Health Campus[Affiliation]"

Significance: Colorectal cancer incidence has decreased largely due to detection and removal of polyps. Computer-aided diagnosis development may improve on polyp detection and discrimination.

Aim: To advance detection and discrimination using currently available commercial colonoscopy systems, we developed a deep neural network (DNN) separating the color channels from images acquired under narrow-band imaging (NBI) and white-light endoscopy (WLE).

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Effects of (-)-epigallocatechin gallate on the redox reactions of human hemoglobin.

Free Radic Biol Med

September 2008

Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and Research, Food and Drug Administration, National Institutes of Health Campus, Bethesda, MD 20892, USA.

The toxicity of acellular hemoglobin (Hb)-based therapeutics has been attributed in part to the uncontrolled oxidative reactions. A variety of antioxidant strategies to ameliorate potential oxidative damage in vivo have been suggested. We have examined the effects of (-)-epigallocatechin gallate (EGCG), a green tea polyphenol compound widely regarded as a chain-breaking antioxidant, on the oxidative stability of diaspirin crosslinked Hb (DBBF) and its cytotoxic ferryl intermediate.

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First-generation blood substitutes: what have we learned? Biochemical and physiological perspectives.

Expert Opin Biol Ther

May 2007

Center for Biologics Evaluation and Research, Food and Drug Administration, Laboratory of Biochemistry and Vascular Biology, Division of Hematology, National Institutes of Health Campus, Bethesda, MD 20892, USA.

Chemically modified or recombinant hemoglobin (Hb)-based oxygen carriers (HBOCs) have been developed as oxygen therapeutics or 'blood substitutes' for use in a variety of clinical settings. Oxidative and nitrosative reactions of acellular Hb can limit the effectiveness and compromise the safety of HBOCs. The reactions between Hb and biologically relevant redox active molecules may also perturb redox sensitive signaling pathways.

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A new tyrosine phosphorylation site in PLC gamma 1: the role of tyrosine 775 in immune receptor signaling.

J Immunol

May 2005

Division of Monoclonal Antibodies, Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, National Institutes of Health Campus, Bethesda, MD 20892, USA.

Phospholipase Cgamma (PLCgamma) is a ubiquitous gatekeeper of calcium mobilization and diacylglycerol-mediated events induced by the activation of Ag and growth factor receptors. The activity of PLCgamma is regulated through its controlled membrane translocation and tyrosine (Y) phosphorylation. Four activation-induced tyrosine phosphorylation sites have been previously described (Y472, Y771, Y783, and Y1254), but their specific roles in Ag receptor-induced PLCgamma1 activation are not fully elucidated.

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Hemoglobin-based blood substitutes and the hazards of blood radicals.

Free Radic Res

October 2000

Laboratory of Plasma Derivatives, Center for Biologics Evaluation and Research, Food and Drug Administration, National Institutes of Health Campus, Bethesda, Maryland 20892, USA.

Cell-free hemoglobins, chemically altered or genetically expressed in microbial host systems, have been developed as oxygen-carrying therapeutics. Site-directed modifications are introduced and serve to stabilize the protein molecules in a tetrameric and/or a polymeric functional form. Animal studies, as well as recent clinical studies, have suggested these proteins probably deliver oxygen to tissues.

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Recombinant native human immunodeficiency virus type 1 (HIV-1) envelope glycoproteins gp160 and gp120 (residues 1 to 511) expressed in insect cells quantitatively adsorbed the group-specific neutralizing antibodies found in human sera. However, these antibodies were not adsorbed by envelope fragment 1 to 471 or 472 to 857 or by both fragments sequentially, even though together they add up to the full-length gp160 sequence. A hybrid envelope glycoprotein was constructed with residues 342 to 511 of the HIV-1 sequence and residues 1 to 399 of the simian immunodeficiency virus type 1 sequence to vary the HIV-1 sequence while preserving its conformation.

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