50 research outputs found

    The Cserénfa experiment.

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    The Cserénfa experiment. On the attempt to install computers and Internet in a tiny village in Hungary Authors: György Lengyel, professor of sociology, Corvinus University of Budapest, Department of Sociology and Social Policy, [email protected] Eliza Eranusz, Ph.D. student, Corvinus University of Budapest Department of Sociology and Social Policy Dániel Füleki, junior research fellow, Corvinus University of Budapest Department of eBusiness László Lőrincz, Ph.D. student, Corvinus University of Budapest Department of Sociology and Social Policy Viktória Siklós, Ph.D. student, Corvinus University of Budapest Department of Sociology and Social Policy Abstract The research aimed at studying social impacts of network-based and organized IT-learning in a local community. At the beginning of the project courses were organized, then computers and Internet accesses were made available for families, and we asked them to provide help for others on a voluntary basis. The turnout of the village Telehouse (the public eAccess point) was monitored at the same time. Focus groups, interviews, computer generated documents and diaries of the participants were the major sources of the research. As for the primary impacts, by the end of the experiment IT knowledge and related aspirations increased although side effects, like envy and frustration also did occur. The Internet activity of the participants was predominated by recreation and not by information gathering or resource extension. As far as wider social aspects are concerned, at the beginning of the project villagers thought that people were reserved, mistrustful and unprepared to help, and this mood did not change much to the end. While children learn basic IT skills in the elementary school adults are worse off in this respect. Therefore organizing courses for them was popular and proved to be useful. Another policy result is that outplacing to networks and the Telehouse satisfy more or less the same potential demand thus it is not advisable to apply both of them in a small settlement. Word count: app. 750

    A nemi hormonok és neuroszteroidok neuroprotektív szerepe: in vivo és in vitro vizsgálatok = Neuroprotective effects of gonadal hormones and neurosteroids: in vivo and in vitro studies

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    A jelen pályázat keretében elvégzett vizsgálatok célja azon sejt és molekuláris szintű mechanizmusok tanulmányozása volt, melyek az öregedésből ill. az agyi sérülésekből adódó morfológiai és funkcionális károsodások enyhítését lehetővé teszik. Különböző állatmodelleken a női nemi hormon (ösztrogén) ill. az egyik neuroszteroid, dehydroepiandoszteron (DHEA) hatását tanulmányoztuk az idegi sérüléseket követő reakciókra. Legfontosabb megállapításaink: A patkány szaglógumó kísérletes deafferentációját követően kialakuló reaktív asztrogliózist az ösztrogén és a DHEA egyaránt csökkenti. Aromatáz gátló fadrozol segítségével igazoltuk, hogy a protektív hatás kialakulásáért nem maga a neuroszteroid, hanem az abból lokálisan szintetizálódó 17β-ösztadiol a felelős. Patkány agykéregben hideg lézióval előidézett sérülés mértékét dehydroepiandoszteron szulfát (DHEAS) kezelésével csökkenteni lehet. Figyelemreméltó, hogy ilyen körülmények között a neuroszteroid protektív hatása kifejezettebb, ha azt a sérülést követően alkalmazzuk. BrdU-val történő jelöléssel igazoltuk, hogy a patkány szaglógumójában az ösztrogén régió-specifikus módon hat az agyterületen folyó neurogenezisre, az újonnan integrálódó interneuronok túlélésére. | In the present project we studied the process of neurodegeneration occurring during normal ageing or induced by injury. By using different animal models we have studied the effects of estrogen and the neurosteroid dehydroepiandrosterone (DHEA) on the neuronal and glial reactions following neuronal injury. Our aim was to identify those cellular and molecular mechanisms, which were responsible for the neuroprotective effects of these steroids. In deafferentated olfactory bulb of adult rats we have demonstrated that DHEA attenuates the glial reaction to denervation and may regulate glial plasticity in the olfactory glomeruli. With the use of aromatase inhibitor fadrozole we have provided evidences that these effects are likely to be mediated by the local conversion of DHEA to 17 β-estradiol. In a focal cortical cold lesion model we have shown that the size of injury can be decreased by dehydroepiandrosterone sulphate (DHEAS). Our observations clearly show that DHEAS is neuroprotective both in pre- and post-traumatic administration and these results suggest that it may be of substantial therapeutic benefit for the treatment of traumatic injury. By using the mitotic marker BrdU we have found that cells destined to the glomerular and granule cell layers react in the same way to chronic estrogen treatment, and the effect of 17 β-estradiol on the neurogenesis and neuron survival is region specific within the adult olfactory bulb

    Sejt-autonóm és nem sejt-autonóm tényezők tanulmányozása a motoros idegsejtek degenerációja során = Study of the role of cell-autonomous and non cell-autonomous processes in the degeneration of motor neurons

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    Kísérleteink során a mozgató idegsejtek kalcium-kötő fehérje tartalmával jellemzett "sejt-autonóm" tulajdonsága és a környéki mikrogliális reakció mértékével jelzett "nem sejt-autonóm" sajátságok akut és krónikus stressz helyzetben kimutatható összefüggéseit vizsgáltuk. Akut sérülést előidéző modellen igazoltuk, hogy a természetesen különböző kalcium-kötő fehérje tartalmú mozgató idegsejtek kalcium-kötő fehérje tartalma és ellenálló képessége között korreláció áll fenn. Továbblépve, az idegsejtek egyfajta kalcium-kötő fehérje tartalmát (parvalbumin) génsebészeti módszerrel megemelve kimutattuk, hogy ezzel a beavatkozással a sejtek korlátozottan megnövelt ellenálló képességgel ruházhatók fel. Génsebészeti úton előidézett krónikus stressz alkalmazásával igazoltuk, hogy az ilyen jellegű ellenálló képesség növelés hatékonysága, kapacitása véges. Ezen kísérletek során derült fény arra, hogy az idegsejtek károsodásához, és pusztulásához a mozgató idegsejtek környéki mikroglia sejtjei aktívan hozzájárulnak, s igazoltuk, hogy a (mozgató) idegsejtek sérüléssel szembeni hatékony védelmének kidolgozásához a mikroglia sejteket is "kezelni" kell. Ezt, az állatkísérletekkel megfelelően alátámasztott stratégiát klinikai gyakorlatban is (csontvelő átültetéssel) kipróbáltuk. Bár az eljárásnak szignifikáns terápiás hatása nem volt, megmutattuk, hogy ezzel a beavatkozással a donor eredetű sejtek a sérülés helyére vándorolnak, melyek így felhasználhatók trofikus faktorok célzott bejuttatásához. | In our study, the interaction between the cell-autonomous properties (characterized by intracellular calcium buffering capacity) and non cell-autonomous properties (characterized by local microglial activation) of motor neurons has been examined experimentally in acute and chronic stress conditions. During acute lesion, evoked by nerve transection, the correlation between the naturally occurring elevated calcium binding protein capacity and increased resistance of motor neurons against injury has been demonstrated. Next, using transgenic technology, it has been proved that by this way though limited, but increased resistance could be transferred to motor neurons, by increasing their parvalbumin content. During these experiments it became also evident that, in certain stress conditions, the neighboring microglial cells could actively contribute to the destruction of motor neurons, thus, to develop an efficient protection against their injury, microglial cells has to be "treated", as well. This strategy, supported by firm experimental data from animal studies, has been tested clinically through bone marrow transplantation in (voluntary) patients with motor neuron disease. Although this intervention did not yield significant therapeutic benefit, it could be demonstrated that a certain population of cells of donor origin migrate to the site of injury, thus might be used as vehicles for targeted delivery of trophic factors to the lesion

    Aromatase and estrogen receptor beta expression in the rat olfactory bulb: neuroestrogen action in the first relay station of the olfactory pathway?

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    The expression pattern of aromatase (ARO), the enzyme converting androgens to estrogens, was analyzed in the olfactory bulb of adult male rats and was compared with the distribution of estrogen receptor beta (ER beta), the main estrogen receptor isoform expressed in this brain region. A strong ARO immunolabeling obtained with a specificity tested antibody was observed in juxtaglomerular neurons of the glomerular layer and a weaker immunoreaction was detected in the mitral cell layer of the main olfactory bulb, while the granule cell layer of the main olfactory bulb as well as all layers in the accessory olfactory bulb showed faint immunolabeling. Fluorescence double labeling experiments revealed that ARO detected in juxtaglomerular neurons of the main olfactory bulb colocalized with tyrosine hydroxylase (TH) and glutamic acid decarboxylase 67 (GAD67), while no colocalization between ARO and the calcium binding proteins calretinin (CR) and calbindin (CB) was observed. Furthermore, the TH immunoreactive neurons expressed metabotropic glutamate receptor 1 (mGluR1) too. ER beta immunoreactivity, in contrast to ARO, was detected in all layers of both the main and accessory olfactory bulb. In the glomerular layer of the main olfactory bulb it was expressed in TH and GAD67 containing juxtaglomerular neurons, and it colocalized with CR, CB and even with glial fibrillary acidic protein too. Our morphological findings suggest that ARO expression is a novel feature of dopaminergic/GABAergic juxtaglomerular neurons in the adult rat main olfactory bulb, and raise the possibility that ARO activity may change in function of olfactory input via mGluR1. In situ estrogen production in the olfactory bulb in turn may modulate interglomerular circuits through ER beta

    Bridges over the digital divide

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    The study investigates the digital divide concerning computer literacy in Hungary. It examines the differences of computer literacy of people with different social-demographic characteristics (gender, settlement type, education, labor market presence and income). It also investigates the intentions to learn computer skills. In this respect, smaller differences have been found then in the case of actual knowledge, which predicts the narrowing down of digital divide in the future. An attempt has been made to identify the institutional, technical and primordial conditions in everyday life that may influence both computer literacy and inclination to master the computer, and hence may function as “bridges” over the digital divide. Four of these factors have been studied: access to computers at the workplace, public internet access at the settlement, communication via cellular phone and effect of the family members’ ICT knowledge. Statistical analysis and in-depth interviews were used as methods of examination. Based on logistic regression models it was found that the bridging factors exert weak or insignificant influence on the willingness to learn computer skills – if they are controlled – so these factors alone are insufficient to bridge the digital divide

    Immun tényezők, parvalbumin és PARP aktiváció jelentősége neurodegeneratív kórképekben = The role of immune factors, parvalbumin and activation of PARP, neurodegenerative diseases

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    A neurodegeneratív betegségekben a károsodás közös útja az intraneuronális Ca emelkedése. Amyotrophiás laterálsclerosisban (ALS), /humán motoneuron (MN) betegség/, Parkinson kórban (PK) és állatkísérletes modelljeikben azok az idegsejtek, amelyek képesek kompenzatórikusan megemelni a Ca-kötő parvalbumin szintjüket, rezisztensek a károsodásra. A sérülékeny sejtek NMDA receptor antagonistákkal, Ca-csatorna gátlókkal és a parvalbumin gén beültetéssel megóvhatók a pusztulástól a kísérletes MN betegségben. DNS károsodás és az intraneuronális Ca emelkedés aktiválja a poly(ADP-ribose) polymerase (PARP) DNS javító enzymet ALS-ben a corticális MN-okban, PK-ban a dopaminerg sejtekben. A túlfokozott aktiváció elhasználva a sejt energia forrásait sejthalált okoz. A PARP aktiválódik a microgliában is, mely szabályozza a helyi immun-gyulladásos reakciót. A PARP gátlók adásának kedvező hatását tapasztaltuk a MN betegség immun-mediált kísérletes modelljében, s potenciálisan használhatónak tűnnek ALS-ben és PK-ban. Az autoimmun IgG intraneuronális felvételéből, a microglia aktiválódásából és antigén prezentáló dendritikus sejtekké alakulásából, T lymphocyták odavándorlásából álló immun-gyulladásos reakció figyelhető meg ALS-ből, PK-ból származó boncolási anyagban az érintett régiókban. A microglia aktiváció gátlók csökkentik a neuronokra káros anyagok elválasztását, akadályozzák a lokális antigén prezentációt és így a neuronokat károsító másodlagos autoimmun reakciót. | The rise in intraneuronal Ca is the common pathway of cell injury in neurodegenerative diseases. The neurons which are able to upregulate a calcium-buffering protein, parvalbumin are resistant to the damage in amyotrophic lateral sclerosis (ALS), in Parkinson disease (PD) and in their animal models. NMDA receptor antagonists, Ca-channel blockers and parvalbumin gene transfer were successfully used for ameliorating the MN damage in animal models. The rise in intraneuronal Ca upregulates the DNA repair enzyme poly(ADP-ribose) polymerase in the cortical MNs in ALS and in the dopaminergic neurons in PD. The overactivation of PARP exhausts the energy sources of the cells leading to death. The PARP is also upregulated in microglia, which dictates the local immune-inflammatory reaction. The beneficial effect of the use of PARP inhibitors is predicted in the treatment of the diseases and was experienced in an immune-mediated model of MN disease. An immune-inflammatory reaction consisting of autoimmune IgG uptake by the neurons, microglia activation and conversion to antigen presenting dendritic cells, and the recruitment of T lymphocytes was noted in autopsy materials from ALS, PD and from Alzheimer disease in the affected areas. The inhibitors of the activation of microglia may be useful to diminish the harmful effect of the materials secreted by it to damage neurons and can prevent the local antigen presentation and the secondary autoimmune attack targeting neurons
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