973 resultados para Science and humanism in the enlightenment
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Chronic ethanol consumption can produce learning and memory deficits. Brain-derived neurotrophic factor (BDNF) and its receptors affect the pathogenesis of alcoholism. In this study, we examined the expression of BDNF, tropomyosin receptor kinase B (TrkB) and p75 neurotrophin receptor (p75NTR) in the hippocampus of a dog model of chronic alcoholism and abstinence. Twenty domestic dogs (9-10 months old, 15-20 kg; 10 males and 10 females) were obtained from Harbin Medical University. A stable alcoholism model was established through ad libitum feeding, and anti-alcohol drug treatment (Zhong Yao Jie Jiu Ling, the main ingredient was the stems of watermelon; developed in our laboratory), at low- and high-doses, was carried out. The Zhong Yao Jie Jiu Ling was effective for the alcoholism in dogs. The morphology of hippocampal neurons was evaluated using hematoxylin-eosin staining. The number and morphological features of BDNF, TrkB and p75NTR-positive neurons in the dentate gyrus (DG), and the CA1, CA3 and CA4 regions of the hippocampus were observed using immunohistochemistry. One-way ANOVA was used to determine differences in BDNF, TrkB and p75NTR expression. BDNF, TrkB and p75NTR-positive cells were mainly localized in the granular cell layer of the DG and in the pyramidal cell layer of the CA1, CA3 and CA4 regions (DG>CA1>CA3>CA4). Expression levels of both BDNF and TrkB were decreased in chronic alcoholism, and increased after abstinence. The CA4 region appeared to show the greatest differences. Changes in p75NTR expression were the opposite of those of BDNF and TrkB, with the greatest differences observed in the DG and CA4 regions.
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The semipalmated sandpiper Calidris pusilla and the spotted sandpiper Actitis macularia are long- and short-distance migrants, respectively. C. pusilla breeds in the sub-arctic and mid-arctic tundra of Canada and Alaska and winters on the north and east coasts of South America. A. macularia breeds in a broad distribution across most of North America from the treeline to the southern United States. It winters in the southern United States, and Central and South America. The autumn migration route of C. pusilla includes a non-stop flight over the Atlantic Ocean, whereas autumn route of A. macularia is largely over land. Because of this difference in their migratory paths and the visuo-spatial recognition tasks involved, we hypothesized that hippocampal volume and neuronal and glial numbers would differ between these two species. A. macularia did not differ from C. pusilla in the total number of hippocampal neurons, but the species had a larger hippocampal formation and more hippocampal microglia. It remains to be investigated whether these differences indicate interspecies differences or neural specializations associated with different strategies of orientation and navigation.
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High plasma levels of homocysteine (Hcy) promote the progression of neurodegenerative diseases. However, the mechanism by which Hcy mediates neurotoxicity has not been elucidated. We observed that upon incubation with Hcy, the viability of a neuroblastoma cell line Neuro2a declined in a dose-dependent manner, and apoptosis was induced within 48 h. The median effective concentration (EC50) of Hcy was approximately 5 mM. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) nuclear translocation and acylation has been implicated in the regulation of apoptosis. We found that nuclear translocation and acetylation of GAPDH increased in the presence of 5 mM Hcy and that higher levels of acetyltransferase p300/CBP were detected in Neuro2a cells. These findings implicate the involvement of GAPDH in the mechanism whereby Hcy induces apoptosis in neurons. This study highlights a potentially important pathway in neurodegenerative disorders, and a novel target pathway for neuroprotective therapy.
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Kirjallisuusarvostelu
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INTRODUCTION: Mesangial cells (MC) may be involved in the glomerular alterations induced by ischemia/reperfusion injury. OBJECTIVE: To evaluate the response of immortalized MC (IMC) to 30 minutes of hypoxia followed by reoxygenation periods of 30 minutes (H/R30) or 24 hours (H/R24). METHODS: The intracellular calcium concentration ([Ca+2]i) was measured before (baseline) and after adding angiotensin II (AII, 10-5 M) in the presence and absence of glybenclamide (K ATP channel blocker). We estimated the level of intracellular ATP, nitric oxide (NO) and PGE2. RESULTS: ATP concentration decreased after hypoxia and increased after reoxygenation. Hypoxia and H/R induced increases in basal [Ca+2]i. AII induced increases in [Ca+2]i in normoxia (97 ± 9%), hypoxia (72 ± 10%) or HR30 (85 ± 17%) groups, but there was a decrease in the response to AII in group H/R24 since the elevation in [Ca+2]i was significantly lower than in control (61 ± 10%, p < 0.05). Glybenclamide did not modify this response. It was observed a significant increase in NO generation after 24 hours of reoxygenation, but no difference in PGE2 production was observed. Data suggest that H/R injury is characterized by increased basal [Ca+2]i and by an impairment in the response of cells to AII. Results suggest that the relative insensibility to AII may be at least in part mediated by NO but not by prostaglandins or vasodilator K ATP channels. CONCLUSION: H/R caused dysfunction in IMC characterized by increases in basal [Ca+2]i during hypoxia and reduction in the functional response to AII during reoxygenation.
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ISBN 978-951-765-806-5Avhandlingen studerar frihamnen Gustavia på ön S:t Barthélemy, den svenska kolonin i Västindien, under de franska revolutionskrigen 1793-1815. Syftet är att kartlägga den ekonomiska aktiviteten genom Gustavia genom ett outforskat källmaterial och analysera hamnens roll i Västindien och i den atlantiska ekonomin under krigsåren. Det viktigaste resultatet av undersökningen är att den påvisar den kortvariga men exceptionella position som Gustavia fick under krigen, vilket ledde till att stora varuflöden gick genom den svenska kolonin och att sjöfart under svensk flagg i regionen tilltog. Krigskonjunkturen hämtade till ön ett stort antal nya invånare, framförallt från angränsande karibiska kolonier men också från USA och Europa. Frihamnen och ön fungerade kort under några decennier som en global marknadsplats i Västindien för handelsmän som kringgick blockader och handelsförbud. Vidare närmar sig även avhandlingen frågor om Sveriges engagemang i slavhandeln på ett systematiskt sätt, och demonstrerar att den svenska slavhandeln var mer omfattande än den tidigare forskningen visat, speciellt efter att rörelsen för slavhandelns förbud fått ett starkt fäste i Storbritannien. De tidigare stora internationella undersökningarna om slavhandeln har ofta missat det svenska inslaget. S:t Barthélemy har fått relativt lite uppmärksamhet i den svenska historieforskningen, och har ofta skildrats som ett exotiskt och ganska betydelselöst inslag i Sverige 1800-talshistoria. Mycket av den tidigare forskningen präglas av det nationalhistoriska perspektivet med kolonins länkar till Stockholm i blickfånget. Avhandlingen påvisar att länkarna mellan kolonin och Stockholm var fåtaliga och att dess ekonomiska betydelse för Sverige var ytterst liten. Däremot omvärderar avhandlingen kolonins betydelsefulla roll i ett större internationellt sammanhang. ----------------------------------------------------------- Väitöskirja käsittelee Gustavian vapaasatamaa Ruotsin Länsi-Intian siirtomaassa Saint-Barthélemyn saarella, Ranskan vallankumoussotien aikana 1793–1815. Tarkoitus on ollut kartoittaa Gustavian kautta kulkevaa taloudellista toimintaa tutkimattomien lähteiden avulla ja arvioida sataman asemaa Länsi-Intiassa sekä atlanttisessa taloudessa sotavuosina.Väitöskirjan tärkein tulos osoittaa sataman sotien aikana saavuttamaa lyhytkestoista mutta poikkeuksellista roolia, mikä johti suuren kaupankäynnin saapumiseen ruotsalaissiirtomaahan sekä siihen, että merenkulku ruotsalaisen lipun alla kiihtyi Länsi-Intian alueella. Sotatalouden nousukausi aikaansai pienelle saarelle muuttoliikkeen myötä suuren väestönkasvun, jonka lähteenä olivat pääsääntöisesti lähisaaret, mutta osa uusista asukkaista tuli myös Yhdysvalloista ja Euroopasta. Gustavian vapaasatama toimi muutaman vuosikymmenen ajan globaalina markkinapaikkana Länsi-Intian kauppamiehille, joilla oli tarve kiertää kauppasaartoja ja -kieltoja. Lisäksi väitöskirja lähestyy kysymystä Ruotsin osallistumisesta orjankauppaan ja osoittaa että ruotsalainen orjakauppa oli laajempaa kuin aiempi tutkimus on väittänyt, etenkin sen jälkeen kun kansanliike orjakauppaa vastaan oli saavuttanut vahvan tuen Iso-Britanniassa. Aiemmat laajat kansainväliset kartoitukset orjakaupasta ovat usein ohittaneet ruotsalaisten osallisuutta tässä yhteydessä. Saint-Barthélemy on aiemmin saanut suhteellisen vähän huomiota ruotsalaisessa historiankirjoituksessa, ja sitä on usein hahmoteltu eksoottisena ja melko merkityksettömänä osana Ruotsin 1800-luvun historiaa. Aiempaa tutkimusta on paljolti leimannut kansallinen historiankirjoitus, jonka keskeisenä kiinnostuksena ovat olleet saaren yhteydet Tukholmaan. Väitöskirja osoittaa kuitenkin että nämä yhteydet olivat heikkoja ja että siirtomaan taloudellinen merkitys Ruotsille oli hyvinkin pieni. Toisaalta väitöskirja arvioi siirtomaan todellista ja tärkeää roolia uudelleen sijoittamalla sen isompaan kansainväliseen asiayhteyteen.
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The credibility of the rules and the elements of power constitute fundamental keys in the analysis of the political institutions. This paper opens the "black box" of the European Union institutions and analyses the problem of credibility in the commitment of the Stability and Growth pact (SGP). This Pact (SGP) constituted a formal rule that tried to enforce budgetary discipline on the European States. Compliance with this contract could be ensured by the existence of "third party enforcement" or by the coincidence of the ex-ante and ex-post interests of the States (reputational capital). The fact is that states such as France or Germany failed to comply with the ruling and managed to avoid the application of sanctions. This article studies the transactions and the hierarchy of power that exists in the European institutions, and analyses the institutional framework included in the new European Constitution.
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The paper argues that if the state, as an expression and part of a pact of domination, operates as a corporate actor with relative autonomy, vision and capacity to promote the development, it is a key institution to the economic transformation. Supported in the neo-Marxism, exposes the limits of institutionalist approach of autonomy of the state to explain its origin, but does not rule out this approach. Maintains that the class-balance theory of the state may explain its relative autonomy and at the same time aid in understanding the historical experiences of social-developmentalist state action, particularly in the social democratic regimes and in the current Latin America.
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ABSTRACTThe term "energy nationalism" is frequently used by academic literature and media, but usually without adequate conceptual accuracy. Despite this, a set of papers deepens the discussion on the relationship between nation states and the energy industry, especially the oil sector. These papers allow identifying fundamental elements to understand the energy nationalism, either complementary or divergent between each other. Thus, this study aims at presenting an interpretation of the concept that fills the gaps left by the above mentioned literature based on a global analysis of the oil industry structure and its historical evolution since the mid-19thcentury.
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