1,872 research outputs found
Evaluation of the first automated thyroglobulin assay
No full textThe aim of this study was to investigate technical and analytical performance of the first automated thyroglobulin (Tg) assay (DPC-Immulite(R); Diagnostic Products Corporation, Los Angeles, USA). In imprecision studies using several human serum pools ranging from 21 to 58 replicates, a coefficient of variation of 9.0 % was obtained at a mean Tg concentration of 0.84 ng/ml and of 6.1 % at a Tg concentration of 62.1 ng/ml. In a method comparison with a non-automated assay (BRAHMS LUMItest Tg(R), BRAHMS, Berlin, Germany) using 383 sera of 303 patients with thyroid carcinoma, regression analysis according to Passing and Bablock yielded in the following equation: Immulite Tg=1.6 x BRAHMS Tg - 0.1 ng/ml (Pearson's r=0.979). Sera obtained from 59 patients with thyroid carcinoma enabled comparative follow-up studies; in all cases qualitative agreement was found with regard to increase or decrease of serum Tg; in eight cases, however, Tg was detected with the Immulite assay but not with the BRAHMS assay. Further follow-up proved the presence of thyroid tissue in these patients. From these and further methodological data (dilution linearity, interference studies, carry-over study, high-dose hook properties, and short report time) it is concluded that the DPC-Immulite Tg assay meets the requirements of routine diagnostic use
Bulk viscosity in F(T, TG) gravity
No full textThe present paper is devoted to exploring the effect of bulk viscosity in the context of F(T, TG) gravity. We consider a time-dependent viscosity model with a particular expression of Hubble parameter. We evaluate viscous effective equation of state parameter for three well-known F(T, TG) models. The behavior of the accelerated expanding universe is explored graphically through the viscous equation of state parameter. This parameter indicates the phantom-dominated era as well as crosses the phantom divide line for all three models. We conclude that the universe shows a transition from quintessence to phantom region in the presence of bulk viscosity.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
() Topology of unimolecular G-quadruplex adopted by dG(TG) and -ion-binding sites
No full text<p><b>Copyright information:</b></p><p>Taken from "NMR evaluation of ammonium ion movement within a unimolecular G-quadruplex in solution"</p><p>Nucleic Acids Research 2007;35(8):2554-2563.</p><p>Published online 4 Apr 2007</p><p>PMCID:PMC1895886.</p><p>© 2007 The Author(s)</p> The three binding sites are labeled as O, I and O. The guanine bases are shown as numbered rectangles, where cyan and magenta rectangles represent nucleobases in and conformation, respectively. () Birds-eye view of a ion above an individual G-quartet
Competition of the 13 bp substrate duplexes and the Tg-containing duplexes in the Endo III reaction
No full text<p><b>Copyright information:</b></p><p>Taken from "Synthesis and characterization of oligonucleotides containing 2′-fluorinated thymidine glycol as inhibitors of the endonuclease III reaction"</p><p>Nucleic Acids Research 2006;34(5):1540-1551.</p><p>Published online 17 Mar 2006</p><p>PMCID:PMC1409675.</p><p>© The Author 2006. Published by Oxford University Press. All rights reserved</p> The P-labeled substrates without fluorine were incubated with Endo III in the presence of the competitors containing Tg. The amounts of the nicked products (standardized to those without the competitors) were plotted against the concentrations of the competitor. Open circles, P-5-Tg + 5-Tg; filled circles, P-5-Tg + 5-Tg; open triangles, P-5-Tg + 5-Tg; filled triangles, P-5-Tg 5-Tg
DNA fusion gene vaccination mobilizes effective anti-leukemic cytotoxic T lymphocytes from a tolerized repertoire
No full textThe majority of known human tumor-associated antigens derive from non-mutated self proteins. T cell tolerance, essential to prevent autoimmunity, must therefore be cautiously circumvented to generate cytotoxic T cell responses against these targets. Our strategy uses DNA fusion vaccines to activate high levels of peptide-specific CTL. Key foreign sequences from tetanus toxin activate tolerance-breaking CD4+ T cell help. Candidate MHC class Ibinding tumor peptide sequences are fused to the C terminus for optimal processing and presentation. To model performance against a leukemia-associated antigen in a tolerized setting, we constructed a fusion vaccine encoding an immunodominant CTL epitopederived from Friend murine leukemia virus gag protein (FMuLVgag) and vaccinated tolerant FMuLVgag-transgenic (gag-Tg) mice. Vaccination with the construct induced epitopespecificIFN-c-producing CD8+ T cells in normal and gag-Tg mice. The frequency and avidity of activated cells were reduced in gag-Tg mice, and no autoimmune injury resulted. However, these CD8+ T cells did exhibit gag-specific cytotoxicity in vitro and in vivo. Also, epitope-specific CTL killed FBL-3 leukemia cells expressing endogenous FMuLVgag antigen and protected against leukemia challenge in vivo. These results demonstrate a simple strategy to engage anti-microbial T cell help to activate epitope-specific polyclonal CD8+ T cell responses from a residual tolerized repertoire
Aromatic () and imino () regions of H NMR spectrum of form of dG(TG) G-quadruplex at 298 K
No full text<p><b>Copyright information:</b></p><p>Taken from "NMR evaluation of ammonium ion movement within a unimolecular G-quadruplex in solution"</p><p>Nucleic Acids Research 2007;35(8):2554-2563.</p><p>Published online 4 Apr 2007</p><p>PMCID:PMC1895886.</p><p>© 2007 The Author(s)</p> Plot of 2D N–H HSQC spectrum (). The cross-peak corresponding to ions in bulk is labeled as B, while those residing at the binding sites within the G-quadruplex are labeled as O, O and I
Gradient interphases between high-Tg epoxy and polyetherimide for advanced joining processes
No full textAdhesive joining of carbon fibre reinforced polymer (CFRP) is cumbersome due to the careful surface preparation required and multiple validation steps to certify adhesion quality. Further these joints are often supplemented by mechanical fastenings add weight whilst also localising bearing stress. As an alternative technique, CFRP parts can be functionalized with thermoplastic surfaces during manufacture to enable cost-effective welding of composite structures. In the process of manufacturing the CFRP, curing an epoxy resin in the presence of the functionalising thermoplastic polymer can lead to local dissolution of the latter in the epoxy, followed by a reaction-induced phase separation. This results in a thermosetting-thermoplastic interphase featuring gradient concentrations and a multiphase morphology, which promotes load transfer between the thermosetting matrix and the thermoplastic joint. The aim of the work presented in this paper was to investigate interphase formation between high-Tg epoxy and polyetherimide (PEI) at different curing temperatures. The morphology was characterised using scanning electron microscopy and the composition of the interphase was quantified through Raman spectroscopy. The curing experiments indicated that temperature has a significant effect on the interphase morphology and led to two different biphasic morphologies which generally increased in size with increasing curing temperature. This suggests that the size of the gradient interphase can be tailored through the curing process, which is as a fundamental step in optimising the structural performance of welded joints with PEI-functionalized epoxy-based CFRPs.Aerospace Manufacturing TechnologiesStructural Integrity & Composite
An exponential convergence estimate for analog neural networks with delay
No full textA componentwise estimate of exponential convergence is obtained for a class of delayed Hopfield type neural networks by using a method based on a comparison principle of delay differential systems. The method is simple and straightforward in analysis, without resorting to any Lyapunov functionals. The result shows explicitly the effect of time delay on exponential decay rate of the networks and is of practical significance for designing fast and stable neural networks. Some existing results via Lyapunov functional method and linear analysis are found to be special cases of the present result. (C) 2001 Elsevier Science B.V. All rights reserved.Physics, MultidisciplinarySCI(E)42ARTICLE1-2113-11828
The effects of triacylglycerols and heparin binding on the structural stability and remodeling of very low- and low-density lipoproteins: implications for type-2 diabetes mellitus
No full textPlasma triacylglycerols (TG) are elevated in diabetes, metabolic syndrome, obesity, and dyslipidemia. Very-low density lipoprotein (VLDL) is the main plasma carrier of TG and the direct metabolic precursor of low-density lipoprotein (LDL), the main carrier of plasma cholesterol and the major causative risk factor for atherosclerosis. Binding of LDL to heparan sulfate on the arterial wall initiates retention and modifications of LDL in the arterial intima, triggering atherosclerosis. Studies presented in this dissertation show that variations in TG levels and lipoprotein binding to heparin, a model for heparan sulfate, alter the structural and biochemical stability of VLDL and LDL, and increase their atherogenic potential.
The molecular consequences of variations in the lipoprotein TG content and LDL-heparin binding were determined by combining heparin affinity chromatography with biochemical, spectroscopic and electron microscopic techniques. Remodeling of human VLDL and LDL by thermal denaturation was used to mimic key aspects of lipoprotein remodeling in vivo. Our studies revealed that increasing the TG content in VLDL promotes changes in the lipoprotein size and release of the exchangeable apolipoproteins. Similarly, increased TG content in LDL promotes lipoprotein remodeling and fusion. Additionally, an increase in TG content increases lipoprotein susceptibility to oxidation and lipolysis, thereby promoting the generation of free fatty acids that augment fusion. Consequently, TG-induced destabilization may be a general property of plasma lipoproteins.
Our studies showed that binding to heparin initiates irreversible pro-atherogenic remodeling of human LDL. As a result of heparin binding, LDL showed decreased structural stability and increased susceptibility to hydrolysis and fusion. Further, phospholipid hydrolysis and/or glycation of LDL (as occurs in diabetes) increased the proteolytic susceptibility of apolipoprotein (apo)B (the major apolipoprotein of VLDL and LDL) and its heparin binding affinity. LDL derived from hyperglycemic patients with type-2 diabetes, became particularly destabilized following heparin binding causing apoB fragmentation and LDL fusion. In summary, binding to heparin alters apoB conformation and triggers pro-atherogenic LDL modifications including proteolysis, lipolysis and structural destabilization. Furthermore, phospholipid lipolysis and glycation of LDL in vitro strengthen its binding to heparin.
Together, these findings help establish a mechanistic link between diabetes and atherosclerosis
Development and initial psychometric evaluation of the transgender adaptation and integration measure (TG AIM)
No full textTransgender individuals have a gender identity or expression that is not congruent with their anatomy (Bullough, 2000). Limited empirical data are available regarding the mental health and general well -being of the transgender population. In addition, few standardized measures have been developed specifically for transgender individuals. The main purpose or this study was item and scale development or a measure or adjustment for transgender adults, as well as the assessment of the internal consistency and validity or the measure. Responses to the Transgender Adaptation and Integration Measure (TG AIM ) were collected from a sample of 108 self-identified male-to-female transsexual adults. Standardized measures or quality or life and self-esteem were also administered to participants in order to assess construct-related validity. Factor analysis of the measure identified four factors: Gender-Related Fears, Psychosocial Impact of Gender Status, Coping and Gender Reorientation Efforts, and Gender Locus or Control. Internal consistency for each of the four factors ranged from r = .59 to r = .81. Psychosocial Impact of Gender Status and Gender-Related Fears were positively correlated with self-esteem and quality or life. Coping and Gender Reorientation Efforts were significantly correlated to both Psychosocial Impact of Gender Status and Gender-Related Fears. Preliminary psychometric analysis resulted in a 15 item. multidimensional measure with three reliable and valid subscales for use with male to female (MtF) transsexual adults. Further psychometric evaluation or the measure for use with other segments of the transgender population is needed.PublishedJournal Articl
- …
