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  • Combined measurement of PEDF, haptoglobin and tau in cerebrospinal fluid improves the diagnostic discrimination between alzheimer\'s disease and other dementias. 21323605

    Using proteomic approach in cerebrospinal fluid (CSF) we identified pigment epithelium-derived factor (PEDF) and Haptoglobin (Hp) as putative markers that could discriminate between AD and other dementias. ELISA assays were developed to measure the levels of PEDF and Hp in CSF from patients with AD (AD, n = 27), non-AD (NAD, n = 30) and in non-demented patients (ND, n = 27). The combined assessment of PEDF, Hp and Tau levels, using Iterative Marginal Optimization, improved the differential diagnosis of AD, especially in patients with moderate to severe dementia (p<0.002). This pilot study highlights the probable different contribution of oxidative mechanisms in dementia.
    Tipo de documento:
    Referencia
    Referencia del producto:
    MAB1059
    Nombre del producto:
    Anti-Pigment Epithelium Derived Factor Antibody, clone 10F12.2
  • Development and evaluation of an antibody capture ELISA for detection of IgG to Epstein-Barr virus in oral fluid samples. 11311354

    The development of an EBV IgG antibody capture ELISA (GACELISA) for detection of EBV viral capsid antigen specific IgG in oral fluids is described. The assay was optimised and evaluated using paired serum and oral fluid samples from healthy laboratory staff (n=82) and oral fluids collected either for routine measles, mumps, and rubella testing (n=629) or for an epidemiological study of atopic dermatitis (n=252). Statistical analysis by mixture modelling was used to determine the GACELISA cut-off and to estimate the sensitivity and specificity of the assay. Sensitivity and specificity was also assessed by comparing the results of immunofluorescence assay for EBV specific IgG in serum with those of GACELISA in 82 matching oral fluids. Compared to serum immunofluorescence assay, oral fluid GACELISA was found to have a sensitivity of 82.2 and 88.9% specificity with these samples. Mixture modelling, predicted the GACELISA to be 88.4% sensitive and of 99.4% specific. The prevalence of antibody to EBV in oral fluids was found to be 73.8% in laboratory staff, 34.4--73.9% in measles, mumps, and rubella patients and 22.2% in atopic dermatitis study participants. A robust, reliable and reproducible EBV GACELISA has been developed which will be a useful tool for epidemiological investigations.
    Tipo de documento:
    Referencia
    Referencia del producto:
    MAB045P
    Nombre del producto:
    Anti-Fluorescein (FITC) Antibody, clone 5D6.2, Peroxidase conjugated
  • High-fat feeding alters the clock synchronization to light. 18936083

    High-fat feeding in rodents leads to metabolic abnormalities mimicking the human metabolic syndrome, including obesity and insulin resistance. These metabolic diseases are associated with altered temporal organization of many physiological functions. The master circadian clock located in the suprachiasmatic nuclei controls most physiological functions and metabolic processes. Furthermore, under certain conditions of feeding (hypocaloric diet), metabolic cues are capable of altering the suprachiasmatic clock's responses to light. To determine whether high-fat feeding (hypercaloric diet) can also affect resetting properties of the suprachiasmatic clock, we investigated photic synchronization in mice fed a high-fat or chow (low-fat) diet for 3 months, using wheel-running activity and body temperature rhythms as daily phase markers (i.e. suprachiasmatic clock's hands). Compared with the control diet, mice fed with the high-fat diet exhibited increased body mass index, hyperleptinaemia, higher blood glucose, and increased insulinaemia. Concomitantly, high-fat feeding led to impaired adjustment to local time by photic resetting. At the behavioural and physiological levels, these alterations include slower rate of re-entrainment of behavioural and body temperature rhythms after 'jet-lag' test (6 h advanced light-dark cycle) and reduced phase-advancing responses to light. At a molecular level, light-induced phase shifts have been correlated, within suprachiasmatic cells, with a high induction of c-FOS, the protein product of immediate early gene c-fos, and phosphorylation of the extracellular signal-regulated kinases I/II (P-ERK). In mice fed a high-fat diet, photic induction of both c-FOS and P-ERK in the suprachiasmatic nuclei was markedly reduced. Taken together, the present data demonstrate that high-fat feeding modifies circadian synchronization to light.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
    Nombre del producto:
    Múltiplo
  • Evidence that a protein kinase A substrate, small heat-shock protein 20, modulates myometrial relaxation in human pregnancy. 18755793

    For a successful human pregnancy, the phasic smooth muscle of the myometrium must remain quiescent until labor. Activation of cAMP/cAMP-dependent protein kinase A (PKA) pathways contributes to this quiescence. The small heat-shock protein 20 (HSP20) is a target of PKA, and phosphorylated HSP20 (pHSP20) modulates relaxation of tonic vascular smooth muscle via interaction with actin, independent of myosin dephosphorylation. Our objective was to determine whether relaxation in human myometrium is associated with changes in phosphorylation of HSP20. Myometrium was obtained at elective cesarean. Elevating cAMP with forskolin or rolipram (a phosphodiesterase inhibitor) caused substantial relaxation of spontaneously contracting human myometrial strips, of 92 +/- 4% (mean +/- sem, n = 10) and 84 +/- 7% (n = 6), respectively. Subsequent two-dimensional electrophoresis with immunoblotting of strip extracts showed a significant 2.6- and 2.1-fold increase in phosphorylated HSP20 (pHSP20) after forskolin (P less than 0.01; n = 5) or rolipram treatment (P less than 0.05; n = 4). Noncyclic-nucleotide-mediated relaxation, induced by the calcium channel blocker nifedipine, did not alter pHSP20. Inhibition of PKA with H89 significantly attenuated rolipram-induced relaxation (P less than 0.01; n = 4), and partially reduced rolipram-stimulated pHSP20. Total and pHSP20 protein was unchanged in term laboring and nonlaboring myometria. Coimmunoprecipitation studies revealed a specific association of HSP20 with alpha-smooth muscle actin and HSP27, a key regulator of actin filament dynamics. Finally, coimmunofluorescence demonstrated moderate colocalization of HSP20 with alpha-smooth muscle actin in the cytoplasm of laboring myometria. Our data support a novel role for pHSP20 in the modulation of cyclic-nucleotide-mediated myometrial relaxation, through interaction with actin. pHSP20 represents an important new target for future tocolytic therapy.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
  • Increased adult hippocampal brain-derived neurotrophic factor and normal levels of neurogenesis in maternal separation rats. 15690366

    Repeated maternal separation of rat pups during the early postnatal period may affect brain-derived neurotrophic factor (BDNF) or neurons in brain areas that are compromised by chronic stress. In the present study, a highly significant increase in hippocampal BDNF protein concentration was found in adult rats that as neonates had been subjected to 180 min of daily separation compared with handled rats separated for 15 min daily. BDNF protein was unchanged in the frontal cortex and hypothalamus/paraventricular nucleus. Expression of BDNF mRNA in the CA1, CA3, or dentate gyrus of the hippocampus or in the paraventricular hypothalamic nucleus was not affected by maternal separation. All animals displayed similar behavioral patterns in a forced-swim paradigm, which did not affect BDNF protein concentration in the hippocampus or hypothalamus. Repeated administration of bromodeoxyuridine revealed equal numbers of surviving, newly generated granule cells in the dentate gyrus of adult rats from the 15 min or 180 min groups. The age-dependent decline in neurogenesis from 3 months to 7 months of age did not differ between the groups. Insofar as BDNF can stimulate neurogenesis and repair, we propose that the elevated hippocampal protein concentration found in maternally deprived rats might be a compensatory reaction to separation during the neonatal period, maintaining adult neurogenesis at levels equal to those of the handled rats.
    Tipo de documento:
    Referencia
    Referencia del producto:
    CYT306
    Nombre del producto:
    ChemiKine Brain Derived Neurotrophic Factor, Sandwich ELISA
  • Spliceosome protein (SRp) regulation of glucocorticoid receptor isoforms and glucocorticoid response in human trabecular meshwork cells. 22205602

    Glaucoma is a leading cause of visual impairment and blindness, with elevated intraocular pressure (IOP) as a major causative risk factor. Glucocorticoid (GC) therapy causes morphologic and biochemical changes in the trabecular meshwork (TM), an ocular tissue involved in regulating IOP, which can lead to the development of glaucoma in susceptible individuals (steroid responders). Steroid responders comprise 40% of the general population and are at higher risk of developing glaucoma. In addition, a majority of glaucoma patients are steroid responders. Differential distribution of various isoforms of GC receptor (GR) may be responsible for this heterogeneity in the steroid response. The alternatively spliced GRβ isoform acts as dominant negative regulator of classical GRα transcriptional activity. mRNA splicing is mediated by spliceosomes, which include serine-arginine rich proteins (SRps). The purpose of this study was to determine whether specific SRps regulate levels of these isoforms and thereby GC response in TM cells.Quantitative RT-PCR, Western blot analysis, and immunocytochemistry were used to determine the differential expression of different SRps (SRp20, 30c, and 40) in human normal and glaucomatous TM cell strains. Bioinformatics was used to find putative binding sites for SRp20 and SRp40 on exon 9 of the GR gene. A peptide modulator of splicing (bombesin) and SRp expression vectors were used to modulate SRp levels and determine their effects on GRα/GRβ ratios as well as dexamethasone (DEX) responsiveness via GRE- luciferase reporter activity, fibronectin, and myocilin induction in TM cells.SRp20, SRp30c, and SRp40 regulate GR splicing and the GC response in TM cells. Modulation of SRp levels altered the GRβ/α ratio that correlated with DEX responsiveness. Bombesin decreased SRp20; increased SRp30c, SRp40 levels, and GRβ/α ratio, and suppressed DEX response in TM cells.Relative levels of SRp20, SRp30c, and SRp40 in TM cells control differential expression of the two alternatively spliced isoforms of the GR and thereby regulate GC responsiveness. Different levels and/or activities of these SRps may account for differential GC sensitivity among the normal and glaucoma populations.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
    Nombre del producto:
    Múltiplo
  • Development of a cluster of differentiation antibody-based protein microarray. 16139293

    Protein microarrays combine aspects of DNA microarrays and ELISA for the parallel interrogation of a biological sample using a multiplex of protein biomarkers. Here we report the development of a protein microarray consisting of a subset of CD antibodies and CRP. Several preparations (culture supernatant, ascites fluid and purified Ig) of each antibody were used in a forward phase protein microarray. Microarrays were fabricated using a non-contact printer delivering 300 pL (+/-30 pL) to specific locations on polyacrylamide gel-based substrates. Following production, microarrays were blocked for non-specific binding and incubated with sera conjugated directly with Cy3. Using CRP as a control biomarker, 12 clinical samples (inflammatory conditions and controls) were interrogated using the protein microarray format and results compared to CRP measured by conventional immunoassay. The data obtained from the microarray correlated with CRP assessed by immunoassay. Subsequently CRP 'positive' samples were interrogated for CD antigen expression; which revealed CD25 and CD45RO expression in all samples. Whilst this study focussed on a subset of CD antibodies, it is anticipated that this array could be expanded to include a larger number of CD antibodies and allow screening of sera from multiple conditions in order to identify disease markers.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
    Nombre del producto:
    Múltiplo
  • Complement and alcoholic liver disease: role of C1q in the pathogenesis of ethanol-induced liver injury in mice. 20416309

    BACKGROUND & AIMS: Complement is involved in the development of alcoholic liver disease in mice; however, the mechanisms for complement activation during ethanol exposure have not been identified. C1q, the recognition subunit of the first complement component, binds to apoptotic cells, thereby activating the classical complement pathway. Because ethanol exposure increases hepatocellular apoptosis, we hypothesized that ethanol-induced apoptosis would lead to activation of complement via the classical pathway.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
    Nombre del producto:
    Múltiplo
  • Cardiac and metabolic changes in long-term high fructose-fat fed rats with severe obesity and extensive intramyocardial lipid accumulation. 20357025

    Metabolic syndrome and obesity-related diseases are affecting more and more people in the Western world. The basis for an effective treatment of these patients is a better understanding of the underlying pathophysiology. Here, we characterize fructose- and fat-fed rats (FFFRs) as a new animal model of metabolic syndrome. Sprague-Dawley rats were fed a 60 kcal/100 kcal fat diet with 10% fructose in the drinking water. After 6, 12, 18, 24, 36, and 48 wk of feeding, blood pressure, glucose tolerance, plasma insulin, glucose, and lipid levels were measured. Cardiac function was examined by in vivo pressure volume measurements, and intramyocardial lipid accumulation was analyzed by confocal microscopy. Cardiac AMP-activated kinase (AMPK) and hepatic phosphoenolpyruvate carboxykinase (PEPCK) levels were measured by Western blotting. Finally, an ischemia-reperfusion study was performed after 56 wk of feeding. FFFRs developed severe obesity, decreased glucose tolerance, increased serum insulin and triglyceride levels, and an initial increased fasting glucose, which returned to control levels after 24 wk of feeding. The diet had no effect on blood pressure but decreased hepatic PEPCK levels. FFFRs showed significant intramyocardial lipid accumulation, and cardiac hypertrophy became pronounced between 24 and 36 wk of feeding. FFFRs showed no signs of cardiac dysfunction during unstressed conditions, but their hearts were much more vulnerable to ischemia-reperfusion and had a decreased level of phosphorylated AMPK at 6 wk of feeding. This study characterizes a new animal model of the metabolic syndrome that could be beneficial in future studies of metabolic syndrome and cardiac complications.
    Tipo de documento:
    Referencia
    Referencia del producto:
    EZRMI-13K
    Nombre del producto:
    Rat/Mouse Insulin ELISA
  • Uncoupling protein-2 negatively regulates insulin secretion and is a major link between obesity, beta cell dysfunction, and type 2 diabetes. 11440717

    beta cells sense glucose through its metabolism and the resulting increase in ATP, which subsequently stimulates insulin secretion. Uncoupling protein-2 (UCP2) mediates mitochondrial proton leak, decreasing ATP production. In the present study, we assessed UCP2's role in regulating insulin secretion. UCP2-deficient mice had higher islet ATP levels and increased glucose-stimulated insulin secretion, establishing that UCP2 negatively regulates insulin secretion. Of pathophysiologic significance, UCP2 was markedly upregulated in islets of ob/ob mice, a model of obesity-induced diabetes. Importantly, ob/ob mice lacking UCP2 had restored first-phase insulin secretion, increased serum insulin levels, and greatly decreased levels of glycemia. These results establish UCP2 as a key component of beta cell glucose sensing, and as a critical link between obesity, beta cell dysfunction, and type 2 diabetes.
    Tipo de documento:
    Referencia
    Referencia del producto:
    RI-13K
    Nombre del producto:
    Rat Insulin RIA