202,052 research outputs found
Selective lesioning of the basal forebrain cholinergic system by intraventricular 192 IgG-saporin: behavioral, biochemical and stereological studies in the rat.
No full textThe elucidation of the functional role of the basal forebrain cholinergic system will require access to a highly specific and efficient cholinergic neurotoxin. Recently, selective depletion of the nerve growth factor (NGF) receptor-bearing cholinergic neurons in the rat basal forebrain and a dramatic loss of cholinergic innervation in the related cortical regions have been obtained following intraventricular injection of a newly introduced immunotoxin, 192 IgG-saporin. Here we extend these initial findings and report that administration of increasing doses (1.25, 2.5, 5.0 or 10 micrograms) of the 192 IgG-saporin conjugate into the lateral ventricles of adult rats induced dose-dependent impairments in the water maze task and passive avoidance retention, but only weak and inconsistent effects on locomotor activity. These behavioural changes were paralleled by a reduction in choline acetyltransferase activity in hippocampus and several cortical areas (up to 97%) and selective depletions of NGF receptor-positive cholinergic neurons in the septal-diagonal band area and nucleus basalis magnocellularis (up to 99%). By contrast, the non-cholinergic parvalbumin-containing neurons in the septum were completely spared, and other cholinergic projection systems (such as in the striatum, thalamus, brainstem and spinal cord) were unaffected even at the highest dose. The observed changes in the water maze and passive avoidance tasks, as well as the cholinergic cell loss, were maintained up to at least 8 months following the intraventricular injection of a single dose (5 micrograms) of the immunotoxin. The results confirm the usefulness of the 192 IgG-saporin toxin for selective and profound lesions of the basal forebrain cholinergic neurons and provide further support for a role of the basal forebrain cholinergic system in cognitive functions
Про задачу вiдокремлення для сiм’ї борелiвських та берiвських G-степенiв мiр зсуву на R
No full textThe separation problem for a family of Borel and Baire G-powers of shift measures on R is studied for an arbitrary infinite additive group G using the technique developed in [Kuipers L., Niederreiter H. Uniform distribution of sequences. – New York etc.: John Wiley & Sons, 1974], [Shiryaev A. N. Probability (in Russian). – Moscow: Nauka, 1980] and [Pantsulaia G. R. Invariant and quasiinvariant measures in infinite-dimensional topological vector spaces. – New York: Nova Sci. Publ., Inc., 2007].Вивчається задача вiдокремлення для сiм’ї борелiвських та берiвських G-степенiв мiр зсуву на R для довiльної нескiнченної адитивної групи G iз використанням пiдходу, розвиненого в роботах [Kuipers L., Niederreiter H. Uniform distribution of sequences. – New York etc.: John Wiley & Sons, 1974], [Ширяев А. Н. Вероятность. – М.: Наука, 1980] та [Pantsulaia G. R. Invariant and quasiinvariant measures in infinite-dimensional topological vector spaces.
– New York: Nova Sci. Publ., Inc., 2007]
Extensive reinnervation of the hippocampus by embryonic basal forebrain cholinergic neurons grafted into the septum of neonatal rats with selective cholinergic lesions.
No full textReconstruction of the septohippocampal pathways by axons extending from embryonic cholinergic neuroblasts grafted into the neuron-depleted septum has been explored in the neonatal rat by using a novel lesioning and grafting protocol. Neonatal ablation of the basal forebrain cholinergic projection neurons, accompanied by extensive bilateral cholinergic denervation of the hippocampus and neocortex, was produced at postnatal day (PD) 4 by 192 immunoglobulin (IgG)-saporin intraventricularly. Four days later, cholinergic neuroblasts (from embryonic day 14 rats) were implanted bilaterally into the neuron-depleted septum by using a microtransplantation approach. The results show that homotopically implanted septal neurons survive and integrate well into the developing septal area, extending axons caudally along the myelinated fimbria-fornix and supracallosal pathways that are able to reach the appropriate targets in the denervated hippocampus and cingulate cortex as early as 4 weeks postgrafting. Moreover, the laminar innervation patterns established by the graft-derived axons closely resembled the normal ones and remained essentially unchanged up to at least 6 months, which was the longest postoperative time studied. The reinnervating fibers restored tissue choline acetyltransferase activity (up to 50% of normal) in the dorsal hippocampus and the parietooccipital cortex. Retrograde labeling with Fluoro-Gold from the host hippocampus combined with immunocytochemistry confirmed that most of the projecting neurons, indeed, were cholinergic. The results suggest that the graft-host interactions that are necessary for target-directed axon growth are present in the septohippocampal system during early postnatal maturation. Thus, the present approach may contribute to overcome the functional limitations inherent in the use of ectopically placed intrahippocampal transplants
Effect of microwave radiation on the permeability of carbonic anhydrase loaded unilamellar liposomes
No full textThe influence of 2.45 GHz microwave exposure (6 mW/g) on the diffusion processes in enzyme‐loaded unilamellar liposomes as bioreactors was studied. The enzyme carbonic anhydrase (CA) was entrapped into cationic unilamellar vesicles. Previous kinetic experiments showed a very low self‐diffusion rate of the substrate p‐nitrophenyl acetate (PNPA) across intact liposome bilayer. A twofold increase in the diffusion rate of PNPA through the lipid bilayer was observed after 120 min of microwave radiation compared to temperature control samples. The microwave effect was time dependent. The enzyme activity, as a function of increased diffusion of PNPA, rises over 120 min from 22.3% to 80%. The increase in stearylamine concentration reduces the enzyme activity from 80% to 65% at 120 min. No enzyme leakage was observed. © 1994 Wiley‐Liss, Inc. Copyright © 1994 Wiley‐Liss, Inc., A Wiley Compan
LNS Modality
No full textMielicki, M. K., Koppel, R. H., Valencia, G., & Wiley, J. (2018). Measuring working memory capacity with the letter-number sequencing task: Advantages of visual administration. Applied Cognitive Psychology, 32, 805-814. https://doi.org/10.1002/acp.346
LNS Modality
No full textMielicki, M. K., Koppel, R. H., Valencia, G., & Wiley, J. (2018). Measuring working memory capacity with the letter-number sequencing task: Advantages of visual administration. Applied Cognitive Psychology, 32, 805-814. https://doi.org/10.1002/acp.346
Effects of neonatal lesions of the basal forebrain cholinergic system by 192 IgG-saporin: biochemical, behavioural and morphological characterization.
No full textThe dialogue between the author and the hero in the “Notes” of G. R. Derzhavin
No full textВ центре внимания автора статьи «Записки» Г. Р. Державина, представляющие по своей сути его автобиографию. Труд этот был создан на закате жизни, он включает все важнейшие события жизни Г. Р. Державина, поэта и государственного деятеля. Рассказ ведется от третьего лица, что придает особую атмосферу повествованию, выстраивается своеобразный диалог между автором и героем, все это и является предметом исследования автора статьи.The focus of the author of the article “Notes” G. R. Derzhavin, representing in essence his autobiography. This work was created at the end of his life; it includes all the most important events in the life of G. R. Derzhavin, poet and statesman. The story is told in a third person, which gives a special atmosphere to the story, a certain dialogue emerges between the author and the hero, all this is the subject of the author's research
Memo re: Vidal report
No full textMemo from James R. Record to Amon G. Carter enclosed with a report on the plane crash of Wiley Post and Will Rogers
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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