The effect of lipid oxidation state on the physical properties of complexes formed by plasmid DNA and the redox-active lipid bis-(11-ferrocenylundecyl)dimethylammonium bromide (BFDMA) is reported. With increasing concentration of BFDMA, the hydrodynamic sizes of complexes formed by BFDMA and DNA (in the presence of 1 mM Li(2)SO(4)) pass through a maximum and the zeta-potential changes monotonically from -40 mV to +40 mV. In contrast, complexes formed by oxidized BFDMA and DNA exhibit a minimum in size and maintain a negative zeta-potential with increasing concentration of BFDMA.
View Article and Find Full Text PDFSkin esterases serve an important pharmacological function as they can be utilised for activation of topically applied ester prodrugs. Understanding the nature of these enzymes, with respect to their role and local activity, is essential to defining the efficacy of ester prodrugs. Minipigs are used as models to study the kinetics of absorption of topically applied drugs.
View Article and Find Full Text PDFThe capacity of human, minipig, and rat skin and liver subcellular fractions to hydrolyze the anesthetic ester procaine was compared with carboxylesterase substrates 4-methylumbelliferyl-acetate, phenylvalerate, and para-nitrophenylacetate and the arylesterase substrate phenylacetate. Rates of procaine hydrolysis by minipig and human skin microsomal and cytosolic fractions were similar, with rat displaying higher activity. Loperamide inhibited procaine hydrolysis by human skin, suggesting involvement of human carboxylesterase hCE2.
View Article and Find Full Text PDFHuman liver has numerous hydrolytic enzymes involved in metabolism of endogenous and exogenous esters. Of these enzymes, carboxylesterases (EC 3.1.
View Article and Find Full Text PDFWe report on the influence of polyanion molecular weight on the growth and structure of multilayered thin films fabricated from poly(allylamine) (PAH) and well-defined, end-labeled poly(acrylic acid) (PAA) synthesized by atom transfer radical polymerization. We observed striking differences in the growth of PAH/PAA films fabricated using well-defined PAA compared to films fabricated using higher molecular weight, commercially available PAA. Past studies demonstrate that the thicknesses of PAH/PAA films increase as linear functions of the number of PAH and PAA layers deposited over a broad range of pH (e.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
August 2007
Context: A single-nucleotide polymorphism (SNP) in the human glucocorticoid receptor (hGR) N363S (rs6195) has been the focus of several clinical studies, and some epidemiological data link this SNP to increased glucocorticoid sensitivity, coronary artery disease, and increased body mass index. However, molecular studies in vitro using reporter gene expression systems have failed, for the most part, to define a link between this polymorphism and altered glucocorticoid receptor function.
Objective: The objective of this study was to address the biological relevancy of N363S SNP in GR function by establishing stable U-2 OS (human osteosarcoma) cell lines expressing wild-type hGR or N363S and examining these receptors under a variety of conditions that probe for GR activity including human gene microarray analysis.
We report characterization of aqueous solutions of dilute Lambda phage DNA containing the redox-active surfactant (11-ferrocenylundecyl)trimethylammonium bromide (FTMA) as a function of the oxidation state of the FTMA. FTMA undergoes a reversible one-electron oxidation from a reduced state that forms micelles in aqueous solution to an oxidized state (containing the ferrocenium cation) that does not self-associate in solution. This investigation sought to test the hypothesis that FTMA can be used to achieve reversible control over the conformation of DNA-surfactant complexes in solution.
View Article and Find Full Text PDFThe conjugation of cationic protein transduction domains to proteins results in an increase in the extent to which proteins are internalized by cells. This investigation sought to determine whether the conjugation of a protein transduction domain to a functional protein could be used to facilitate the incorporation of the protein into multilayered polyelectrolyte films and, subsequently, whether these films could be used to promote surface-mediated protein transduction. We demonstrate that it is possible to fabricate multilayered assemblies 80 nm thick using sodium polystyrene sulfonate (SPS) and bovine pancreatic ribonuclease (RNase A) conjugated to the cationic protein transduction domain nonaarginine (R(9)) using an entirely aqueous layer-by-layer process.
View Article and Find Full Text PDFWe demonstrate, through structural refinement from synchrotron X-ray diffraction data, that the mechanism of the transformation between lithium amide and lithium imide during hydrogen cycling in the important Li-N-H hydrogen storage system is a bulk reversible reaction that occurs in a non-stoichiometric manner within the cubic anti-fluorite-like Li-N-H structure.
View Article and Find Full Text PDFHuman glucocorticoid receptor (hGR) is expressed as two alternately spliced C-terminal isoforms, alpha and beta. In contrast to the canonical hGRalpha, hGRbeta is a nucleus-localized orphan receptor thought not to bind ligand and not to affect gene transcription other than by acting as a dominant negative to hGRalpha. Here we used confocal microscopy to examine the cellular localization of transiently expressed fluorescent protein-tagged hGRbeta in COS-1 and U-2 OS cells.
View Article and Find Full Text PDFJ Steroid Biochem Mol Biol
December 2006
Glucocorticoids regulate diverse physiological effects in virtually every organ and tissue in the body. Glucocorticoid actions are mediated through the glucocorticoid receptor (GR), a ligand-dependent transcriptional factor that activates or represses gene transcription. Since, the cloning of the human GR in 1985, research efforts have been focused on describing the mechanism of action exerted by one of the GR isoforms, GRalpha.
View Article and Find Full Text PDFMaterials that permit control over the release of DNA from the surfaces of topologically complex implantable devices, such as intravascular stents, could contribute to the development of new approaches to the localized delivery of DNA. We report the fabrication of ultrathin, multilayered polyelectrolyte films that permit both the immobilization and controlled release of plasmid DNA from the surfaces of stainless steel intravascular stents. Our approach makes use of an aqueous-based, layer-by-layer method for the assembly of nanostructured thin films consisting of alternating layers of plasmid DNA and a hydrolytically degradable polyamine.
View Article and Find Full Text PDFAlthough LXXLL motifs in coactivators mediate binding to liganded nuclear receptors, the roles of comparable motifs within nuclear receptors are less understood. We investigated the role of the LXXLL motifs in the human glucocorticoid receptor both in transcriptional activation and repression of gene expression. The two conserved LXXLL motifs within the ligand binding domain of the receptor, amino acids 532-536 (helix 1) and 718-722 (helix 10), were characterized by evaluating LXXLL mutant receptors as well as comparable mutants in other helices of the ligand binding domain.
View Article and Find Full Text PDFObjective: This study compared the quality of treatment relationships and engagement in peer-based and regular case management. It also assessed the value of positive relationship qualities in predicting motivation for and use of community-based services for persons with severe mental illness.
Methods: One hundred thirty-seven adults with severe mental illness participated in a 2x2 prospective longitudinal randomized clinical trial with two levels of case management intervention (peer and regular) and two interviews (six and 12 months).
Non-steroidal anti-inflammatory drugs (NSAIDs) represent a clinically important class of agents. NSAIDs are commonly used in treatment of conditions such as headache, fever, inflammation and joint pain. Complications often arise from chronic use of NSAIDs.
View Article and Find Full Text PDFConjugated linoleic acid (CLA) has been shown to enhance paracellular and transcellular Ca transport across human intestinal-like Caco-2 cell monolayers. The mechanisms of action, however, are still unclear. Therefore, this study investigated the molecular mechanisms underlying CLA-induced stimulation of Ca transport by use of preliminary microarray data together with more detailed and comprehensive quantitative reverse transcriptase-PCR analysis.
View Article and Find Full Text PDFCardiovasc Hematol Agents Med Chem
April 2006
Aldosterone is a mineralocorticoid primarily produced in the zona glomerulosa of the adrenal gland. For many years, aldosterone (Aldo) was thought to have its sole site of action in the kidney, where it regulated sodium excretion and potassium reabsorption. It is now known that Aldo is produced in cardiovascular tissues, and has been implicated in the development of ventricular hypertrophy and cardiac fibrosis.
View Article and Find Full Text PDFThe ability of two redox-active, ferrocene-containing cationic lipids [11-(ferrocenylundecyl)trimethylammonium bromide (FTMA) and bis(11-ferrocenylundecyl)dimethylammonium bromide (BFDMA)] to transfect mammalian cells was investigated. This study sought to determine the range of conditions over which these lipids were capable of transfecting cells and whether the oxidation state of the ferrocenyl groups in these materials could be used to influence the extent of transfection. Experiments conducted in the COS-7 cell line demonstrated that reduced and oxidized FTMA were substantially cytotoxic and did not transfect cells.
View Article and Find Full Text PDFA ferrocene-containing, redox-active cationic lipid that can be transformed using electrochemical methods yields large differences in cell transfection depending on the oxidation state of the lipid. Expression of enhanced green fluorescent protein and firefly luciferase occurs at very high levels when DNA lipoplexes are formulated using the lipid in the reduced state. In contrast, transfection is negligible when oxidized lipid is used.
View Article and Find Full Text PDFMultilayered polyelectrolyte films fabricated from plasmid DNA and a hydrolytically degradable synthetic polycation can be used to direct the localized transfection of cells without the aid of a secondary transfection agent. Multilayered assemblies 100 nm thick consisting of alternating layers of synthetic polymer and plasmid DNA encoding for enhanced green fluorescent protein (EGFP) were deposited on quartz substrates using a layer-by-layer fabrication procedure. The placement of film-coated slides in contact with COS-7 cells growing in serum-containing culture medium resulted in gene expression in cells localized under the film-coated portion of the slides.
View Article and Find Full Text PDFIntroduction: Conjugated linoleic acid (CLA) has been shown to positively influence calcium and bone metabolism in experimental animals and cells in culture, but there are limited human data available.
Objective: To investigate the effect of CLA supplementation on biomarkers of calcium and bone metabolism in healthy adult males.
Design: The study consisted of a double-blind, placebo-controlled trial in which 60 healthy adult males (aged 39-64 y) were randomly assigned to receive daily either 3.
Prostaglandins Leukot Essent Fatty Acids
March 2005
Conjugated linoleic acid (CLA) increases paracellular permeability across human intestinal-like Caco-2 cell monolayers, which transport Ca predominantly by the transcellular route. In vivo, however, paracellular Ca transport is the predominant route of Ca transport. Therefore, the objective of this study was to investigate the effect of CLA on transepithelial Ca transport in Caco-2 cells transporting Ca predominantly by the paracellular route.
View Article and Find Full Text PDFProstaglandins Leukot Essent Fatty Acids
January 2005
Studies in experimental animals and murine osteoblast cells in culture have produced conflicting findings on the effect of conjugated linoleic acid (CLA) on bone formation. The present study investigated the influence of CLA on viability and metabolism of two human osteoblast-like cell lines (SaOS2 and MG63). Both cell lines were exposed to increasing concentrations (0-50 microM) of CLA either as pure cis (c) 9: trans (t) 11 and t10:c12 CLA isomers or a blend of isomers, or linoleic acid (C18:2).
View Article and Find Full Text PDFFor the development of human immunodeficiency virus type 1 (HIV-1) vaccines, traditional approaches inducing virus-neutralizing antibodies have so far failed. Thus the effort is now focused on elicitation of cellular immunity. We are currently testing in clinical trials in the United Kingdom and East Africa a T-cell vaccine consisting of HIV-1 clade A Gag-derived immunogen HIVA delivered in a prime-boost regimen by a DNA plasmid and modified vaccinia virus Ankara (MVA).
View Article and Find Full Text PDFThe effect of polyunsaturated fatty acids (PUFA), in particular conjugated linoleic acid (CLA), on Ca and bone metabolism is unclear. In a 2x2 factorial design study, forty male 4-week-old rats were fed a control diet containing 70 g added fat (soyabean oil (SBO; n-6 PUFA-rich diet) or menhaden oil-safflower oil (MSO; n-3 PUFA-rich diet))/kg diet with 0 or 10 g CLA/kg for 8 weeks. Ex vivo prostaglandin E2 biosynthesis by bone organ culture was significantly higher (P<0.
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