Cartas enviadas por Federico Biggi a Justo Garate

3 cartas (manuscritas) ; entre 210x295 y 210x310

Increased expression of cystine/glutamate antiporter in multiple sclerosis

Background: Glutamate excitotoxicity contributes to oligodendrocyte and tissue damage in multiple sclerosis (MS). Intriguingly, glutamate level in plasma and cerebrospinal fluid of MS patients is elevated, a feature which may be related to the pathophysiology of this disease. In addition to glutamate transporters, levels of extracellular glutamate are controlled by cystine/glutamate antiporter x(c)(-), an exchanger that provides intracellular cystine for production of glutathione, the major cellular antioxidant. The objective of this study was to analyze the role of the system x(c)(-) in glutamate homeostasis alterations in MS pathology. -- Methods: Primary cultures of human monocytes and the cell line U-937 were used to investigate the mechanism of glutamate release. Expression of cystine glutamate exchanger (xCT) was quantified by quantitative PCR, Western blot, flow cytometry and immunohistochemistry in monocytes in vitro, in animals with experimental autoimmune encephalomyelitis (EAE), the animal model of MS, and in samples of MS patients. -- Results and discussion: We show here that human activated monocytes release glutamate through cystine/glutamate antiporter x(c)(-) and that the expression of the catalytic subunit xCT is upregulated as a consequence of monocyte activation. In addition, xCT expression is also increased in EAE and in the disease proper. In the later, high expression of xCT occurs both in the central nervous system (CNS) and in peripheral blood cells. In particular, cells from monocyte-macrophage-microglia lineage have higher xCT expression in MS and in EAE, indicating that immune activation upregulates xCT levels, which may result in higher glutamate release and contribution to excitotoxic damage to oligodendrocytes. -- Conclusions: Together, these results reveal that increased expression of the cystine/glutamate antiporter system x(c)(-) in MS provides a link between inflammation and excitotoxicity in demyelinating diseases.

Asymmetric flow networks

This paper provides a new model of network formation that bridges the gap between the two benchmark models by Bala and Goyal, the one-way flow model, and the two-way flow model, and includes both as particular extreme cases. As in both benchmark models, in what we call an "asymmetric flow" network a link can be initiated unilaterally by any player with any other, and the flow through a link towards the player who supports it is perfect. Unlike those models, in the opposite direction there is friction or decay. When this decay is complete there is no flow and this corresponds to the one-way flow model. The limit case when the decay in the opposite direction (and asymmetry) disappears, corresponds to the two-way flow model. We characterize stable and strictly stable architectures for the whole range of parameters of this "intermediate" and more general model. We also prove the convergence of Bala and Goyal's dynamic model in this context.

Dispositiboen elektronika

Helburuak: Liburu hau Telekomunikazio Ingeniaritza Titulazioan enborrezkoa den Dispositiboen Elektronika irakasgaian erabiltzen da. Ikasleek elektronikarekin duten lehenengo harremana hau izaten denez, irakasgaiaren helburu nagusia oinarrizko osagaien ezaugarriak eta funtzionamenduaren printzipioak ezagutaraztea da. Norentzat izan daiteke baliagarria: Testua Ingeniaritza Eskolako Lehenengo Ikasturteko ikasleentzat bereziki prestatu da, baina dispositiboen funtzionamendua eta anplikazio-sistema sinpleak azaltzen dituenez, oso baliagarria gerta daiteke, orobat, edozein maila eta titulazioko Elektronika-ikasleentzat -edota ikasle horiei irakatsi behar dietenentzat.

Gailuen elektronika: azterketen bilduma (1999-2009)

Helburuak: Liburu honek Gailuen Elektronika irakasgaian azken urteotan egin diren azterketak jasotzen ditu. Hortaz, ikasleek azterketak prestatzeko eta, oro har, elektronika ikasteko oso baliagarritzat jotzen dugu. Irakasgaiaren helburu nagusia diren oinarrizko osagaien ezaugarriak eta funtzionamenduaren printzipioak lantzen dira. Norentzat izan daiteke baliagarria: Testua Ingeniaritza Eskolako Lehenengo Ikasturteko ikasleentzat bereziki prestatu da, baina gailuen funtzionamendua eta anplikazio-sistema sinpleak aztertzen dituzten ariketak jasotzen dituenez, oso baliagarria gerta daiteke, orobat, edozein maila eta titulazioko Elektronika-ikasleentzat -edota ikasle horiei irakatsi behar dietenentzat.

Oinarrizko elektronika laborategia I

Helburuak: Material hau, Telekomunikazio Ingeniaritza Titulazioan enborrezkoa den Oinarrizko Elektronika Laborategia I (OEL I) irakasgaian erabiltzen da. Ikasleak laborategiarekin duen lehenengo harremana izaten denez, irakasgaiaren helburu nagusia Elektronika laborategietan oinarrizkoak diren osagaiak, sorgailuak eta neurgailuak ezagutzea da. Norentzat izan daiteke baliagarria: Testuak, Ingeniaritza Eskolako Lehenengo Ikasturteko ikasleentzat bereziki prestatu badira ere, lantzen diren kontzeptuak oinarrizkoak direnez, baliagarriak gerta daitezke, oro har, Elektronikan lehenengo urratsak egiten ari direnentzat -edota hauei irakatsi behar dietenentzat.

Problemas de la traducción literaria

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

Ethnolinguistic democracy, translation policy and contemporary world order (dis)order

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

The study of film adaptation: a state of the art and some "new" functional proposals

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

Lang's M, investigation, and fascism: Bataille, Benjamin, and the limits of popular genre

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

El serial clásico de la BBC: la adaptación literaria como servicio público

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

La poesía inglesa y alemana en la revista Cántico

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

A Passage to India: from novel to film. Some problems of "translation"

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

De la Viena "Fin-de-Siècle" al París "Rive-Gauche": Reigen/La Ronde

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

Traducción y manipulación: el caso de Ezra Pound

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)