78 research outputs found

    Cholinergic Activation of M2 Receptors Leads to Context-Dependent Modulation of Feedforward Inhibition in the Visual Thalamus

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    The temporal dynamics of inhibition within a neural network is a crucial determinant of information processing. Here, the authors describe in the visual thalamus how neuromodulation governs the magnitude and time course of inhibition in an input-dependent way

    Gene expression profiling identifies inflammation and angiogenesis as distinguishing features of canine hemangiosarcoma

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    <p>Abstract</p> <p>Background</p> <p>The etiology of hemangiosarcoma remains incompletely understood. Its common occurrence in dogs suggests predisposing factors favor its development in this species. These factors could represent a constellation of heritable characteristics that promote transformation events and/or facilitate the establishment of a microenvironment that is conducive for survival of malignant blood vessel-forming cells. The hypothesis for this study was that characteristic molecular features distinguish hemangiosarcoma from non-malignant endothelial cells, and that such features are informative for the etiology of this disease.</p> <p>Methods</p> <p>We first investigated mutations of VHL and Ras family genes that might drive hemangiosarcoma by sequencing tumor DNA and mRNA (cDNA). Protein expression was examined using immunostaining. Next, we evaluated genome-wide gene expression profiling using the Affymetrix Canine 2.0 platform as a global approach to test the hypothesis. Data were evaluated using routine bioinformatics and validation was done using quantitative real time RT-PCR.</p> <p>Results</p> <p>Each of 10 tumor and four non-tumor samples analyzed had wild type sequences for these genes. At the genome wide level, hemangiosarcoma cells clustered separately from non-malignant endothelial cells based on a robust signature that included genes involved in inflammation, angiogenesis, adhesion, invasion, metabolism, cell cycle, signaling, and patterning. This signature did not simply reflect a cancer-associated angiogenic phenotype, as it also distinguished hemangiosarcoma from non-endothelial, moderately to highly angiogenic bone marrow-derived tumors (lymphoma, leukemia, osteosarcoma).</p> <p>Conclusions</p> <p>The data show that inflammation and angiogenesis are important processes in the pathogenesis of vascular tumors, but a definitive ontogeny of the cells that give rise to these tumors remains to be established. The data do not yet distinguish whether functional or ontogenetic plasticity creates this phenotype, although they suggest that cells which give rise to hemangiosarcoma modulate their microenvironment to promote tumor growth and survival. We propose that the frequent occurrence of canine hemangiosarcoma in defined dog breeds, as well as its similarity to homologous tumors in humans, offers unique models to solve the dilemma of stem cell plasticity and whether angiogenic endothelial cells and hematopoietic cells originate from a single cell or from distinct progenitor cells.</p

    Bartter- and Gitelman-like syndromes: salt-losing tubulopathies with loop or DCT defects

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    Salt-losing tubulopathies with secondary hyperaldosteronism (SLT) comprise a set of well-defined inherited tubular disorders. Two segments along the distal nephron are primarily involved in the pathogenesis of SLTs: the thick ascending limb of Henle’s loop, and the distal convoluted tubule (DCT). The functions of these pre- and postmacula densa segments are quite distinct, and this has a major impact on the clinical presentation of loop and DCT disorders – the Bartter- and Gitelman-like syndromes. Defects in the water-impermeable thick ascending limb, with its greater salt reabsorption capacity, lead to major salt and water losses similar to the effect of loop diuretics. In contrast, defects in the DCT, with its minor capacity of salt reabsorption and its crucial role in fine-tuning of urinary calcium and magnesium excretion, provoke more chronic solute imbalances similar to the effects of chronic treatment with thiazides. The most severe disorder is a combination of a loop and DCT disorder similar to the enhanced diuretic effect of a co-medication of loop diuretics with thiazides. Besides salt and water supplementation, prostaglandin E2-synthase inhibition is the most effective therapeutic option in polyuric loop disorders (e.g., pure furosemide and mixed furosemide–amiloride type), especially in preterm infants with severe volume depletion. In DCT disorders (e.g., pure thiazide and mixed thiazide–furosemide type), renin–angiotensin–aldosterone system (RAAS) blockers might be indicated after salt, potassium, and magnesium supplementation are deemed insufficient. It appears that in most patients with SLT, a combination of solute supplementation with some drug treatment (e.g., indomethacin) is needed for a lifetime

    Genetics of the iron dicitrate transport system of Escherichia coli.

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    Escherichia coli B and K-12 express a citrate-dependent iron(III) transport system for which three structural genes and their arrangement and products have been determined. The fecA gene of E. coli B consists of 2,322 nucleotides and encodes a polypeptide containing a signal sequence of 33 amino acids. The cleavage site was determined by amino acid sequence analysis of the unprocessed protein and the mature protein. For the processed form a length of 741 amino acids was calculated. The mature FecA protein in the outer membrane contains at the N terminus the "TonB box," a pentapeptide, which has hitherto been found in all receptors and colicins which functionally require the TonB protein. In addition, the dyad repeat sequence GAAAATAATTCTTATTTCG is proposed to serve as the binding site of the Fur iron repressor protein. The fecB gene was mapped downstream of fecA and encodes a protein with an apparent molecular weight of 30,000. It was synthesized as a precursor, and the mature form was found in the periplasm. The fecD gene follows fecB and was related to a membrane-bound protein with an apparent molecular weight of 28,000. In Mu d1 insertion mutants upstream of fecA, the fec genes were not inducible by iron limitation and citrate, indicating a regulatory region, termed fecI, which controls fec gene expression

    (Re)presentation of consumer in Latvian advertisements during perestroika and post soviet period: discourse of gender identity (1985–2004)

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    Elektroniskā versija nesatur pielikumusPromocijas darbs veltīts reklāmas lomai patērētāja identitātes un dzimtes priekšstatu veidošanā Latvijā no 1985. līdz 2004. gadam. Tā uzmanības centrā reklāmas (at)veidoto patēriņa un patērētāju dzīvesstila paraugu nozīme dzimtes identitātes nostiprināšanā un normalizēšanā pēcpadomju periodā. Darba teorētiskajā daļā iztirzāta reklāmas sociālā loma un tās komunicētās simboliskās nozīmes, kā arī vizuālās komunikācijas, identitātes un patēriņa problēmas. Tajā analizēta padomju un pēcpadomju patērētāja identitāte, tās veidošanu ietekmējošie nosacījumi, kā arī transformācijas perioda sociālā vide un izmaiņas reklāmas praksē. Pētījums veikts, izmantojot diskursa analīzes pieeju un kontentanalīzi. Darba rezultāti raksturo Latvijas reklāmas attīstību, pēcpadomju sabiedrību, patērnieciskā dzīves veida iedibināšanos, tādējādi bagātinot zināšanas par Latvijas iedzīvotāju identitātēm. Atslēgvārdi: identitāte, patēriņš, dzimte, dzimtes displejs, reklāma, pēcpadomju, patērētājs, vizuālā komunikācijaThe doctoral thesis is dedicated to the role of advertising in creation of consumer identities and gender notions in Latvia from 1985 until 2004. It focuses on the role consumption and consumer lifestyle models (re)produced by advertisements played in strengthening and normalizing of gender identity in the post-Soviet period. The theoretical part of the thesis discusses the social role of advertising and symbolic meanings it communicates, as well as visual communication, identity and consumption issues. The thesis analyzes the Soviet and post-Soviet consumer's identity, conditions influencing its formation as well as social environment and changes to advertising practice during the period of transformation. The study is conducted using a discourse analysis approach and content analysis. Results of the study characterise development of advertising in Latvia, transition processes of post-Soviet society and establishment of consumer life style thus enriching knowledge about various identities of Latvia’s inhabitants. Keywords: identity, consumption, gender, gender displays, advertising, post-Soviet, consumer, visual communicatio

    Extensive Endoscopic Image-Guided Sinus Surgery Decreases BPI-ANCA in Patients with Cystic Fibrosis

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    Antineutrophil cytoplasm autoantibodies (ANCA) directed against bactericidal/permeability-increasing protein (BPI) are common in patients with cystic fibrosis (CF), and serum levels are correlated with lung colonization by Pseudomonas aeruginosa and the severity of lung damage. The production of BPI-ANCA may be due to the costimulation of BPI when mounting an immune response against P. aeruginosa. The effect of surgery aiming to eradicate bacteria and infected tissue on BPI-ANCA levels is sparsely described. A cohort of patients with CF were included: 53 patients having extensive image-guided sinus surgery (EIGSS) with topical postoperative antibiotic treatment, 131 non-operated controls and 36 who had double lung transplantation (LTX). In all 219 patients, serum samples before and after surgery or at similar intervals were analysed for IgG and IgA BPI-ANCA. The EIGSS group showed a highly significant decrease in both IgA and IgG BPI-ANCA levels compared with their own preoperative values and control group values (P andlt; 0.0010.02). The LTX patients also showed a highly significant decrease in both IgA and IgG BPI-ANCA levels (P andlt; 0.001). EIGSS and LTX decrease IgA and IgG BPI-ANCA levels in patients with CF, indicating that extensive removal of infected tissue influences the pathogenic process of autoantibody production. The results shown herein are in favour of applying EIGSS in selected patients with CF and for using BPI-ANCA as a surrogate marker for guiding further therapeutic interventions.Funding Agencies|Statens Serum Institut||Candys Foundation||</p
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