Development and validation of an HPLC method for the rapid and simultaneous determination of 6-mercaptopurine and four of its metabolites in plasma and red blood cells

An HPLC method has been developed and validated for the rapid determination of mercaptopurine and four of its metabolites; thioguanine, thiouric acid, thioxanthine and methylmercaptopurine in plasma and red blood cells. The method involves a simple treatment procedure based on deproteinisation by perchloric acid followed by acid hydrolysis and heating for 45 min at 100 degrees C. The developed method was linear over the concentration range studied with a correlation coefficient >0.994 for all compounds in both plasma and erythrocytes. The lower limits of quantification were 13, 14, 3, 2, 95 pmol/8 x 101 RBCs and 2, 5, 2, 3, 20 ng/ml plasma for thioguanine, thiouric acid, mercaptopurine, thioxanthine and methylmercaptopurine, respectively. The method described is selective and sensitive enough to analyse the different metabolites in a single run under isocratic conditions. Furthermore, it has been shown to be applicable for monitoring these metabolites in paediatric patients due to the low volume requirement (200 mu l of plasma or erythrocytes) and has been successfully applied for investigating population pharmacokinetics, pharmacogenetics and non-adherence to therapy in these patients. (C) 2008 Elsevier B.V. All rights reserved.

Emergencias de la mediación intelectual. "La Revista de América" (París, 1912-1914) y la red de escritores latinoamericanos en Europa a comienzos del siglo XX

Este trabajo estudia el proyecto editorial de la Revista de América (1912-1914), fundada en París y dirigida por Francisco García Calderón. Mi propósito es analizar el modo en que muchos de los vínculos entre los escritores latinoamericanos radicados en París entre fines del siglo XIX y la Primera Guerra Mundial se materializaron en la edición de revistas. Propongo examinar las estrategias de difusión de las producciones latinoamericanas en el Viejo Continente, como así también algunos aspectos ideológicos y de intervención intelectual que la revista llegó a articular. En un primer momento, me detengo en los rasgos materiales tanto del proyecto editorial de la revista como de los vínculos entre los latinoamericanos desterrados. Luego indago las distintas formas de mediación crítica, por un lado, y cultural, por otro, que la revista escenificó y, en algunos casos, desarrolló activamente. En efecto, la revista de García Calderón vuelve visible una dimensión mediadora en varios sentidos: mediación crítica entre productores y lectores, pues se propuso como instancia de difusión, al convocar a “a los mejores escritores latinoamericanos”. Al mismo tiempo, propuso otras dos mediaciones: entre pares, al funcionar como consagradora, seleccionando y agrupando simbólicamente a los escritores de cada país latinoamericano. Finalmente, una mediación intercontinental entre culturas en la contemporaneidad, que intentó acercar dos gestos en la acción de la revista: una legitimación del pensamiento y el arte “de ultramar” y una valoración de los desarrollos artísticos europeos del presente.

Del Fichero supremo a la Biblioteca de Babel: Salaverría, precursor de Borges

A juzgar por alguna declaración más bien negativa de Borges sobre la literatura española, se podría creer que esta no influyó demasiado en él. Sin embargo, existen indicios de que pudo haberse inspirado también en determinados escritores españoles coetáneos hoy casi olvidados. Uno de ellos pudo ser José María Salaverría, entre cuyos relatos destaca “El fichero supremo” (1926), del que se ha dicho que “anticipa algunas de las preocupaciones características de un tipo de relato que Jorge Luis Borges elevará años después a la máxima categoría estética”. De hecho, recuerda a “La biblioteca de Babel” (1941) borgiana por su planteamiento hasta el punto de que podría pensarse que el maestro argentino pudo tener presente, a la hora de escribir esa obra maestra, ese cuento de Salaverría, el cual se publicó por primera vez en Caras y Caretas, una revista porteña que Borges reconoció “devorar” en su juventud. Sin embargo, el interés mayor de la comparación entre “El fichero supremo” y “La biblioteca de Babel” no radica tanto en el carácter de posible fuente del primero como en el contraste entre sus formas de presentación narrativa: desde fuera y en tercera persona en Salaverría, en un marco realista; y desde dentro y en primera persona, prácticamente sin marco, en Borges. Este parece desarrollar, en el registro propio de la “imaginación razonada” descrito por él mismo, una virtualidad presente en el relato de Salaverría, cuya comparación con “La biblioteca de Babel” puede suscitar también alguna reflexión sobre el enigma de la identidad y el carácter de la voz enunciadora de la biblioteca universal de Babel. Al menos, esta parece haber hecho realidad en cierto modo, de forma sublime, el patético sueño divino del archivero imaginado por Salaverría.

Novel dermaseptin, adenoregulin and caerin homologs from the Central American red-eyed leaf frog, Agalychnis callidryas, revealed by functional peptidomics of defensive skin secretion

By integrating systematic peptidome and transcriptome studies of the defensive skin secretion of the Central American red-eyed leaf frog, Agalychnis callidryas, we have identified novel members of three previously described antimicrobial peptide families, a 27-mer dermaseptin-related peptide (designated DRP-AC4), a 33-mer adenoregulin-related peptide (designated ARP-AC1) and most unusually, a 27-mer caerin-related peptide (designated CRP-AC1). While dermaseptin and adenoregulin were originally isolated from phyllomedusine leaf frogs, the caerins, until now. had only been described in Australian frogs of the genus, Litoria. Both the dermaseptin and adenoregulin were C-terminally amidated and lacked the C-terminal tripeptide of the biosynthetic precursor sequence. In contrast, the caerin-related peptide, unlike the majority of Litoria analogs. was not C-terminally amidated. The present data emphasize the need for structural characterization of mature peptides to ensure that unexpected precursor cleavages and/or post-translational modifications do not produce mature peptides that differ in structure to those predicted from cloned biosynthetic precursor cDNA. Additionally, systematic study of the secretory peptidome can produce unexpected results such as the CRP described here that may have phylogenetic implications. It is thus of the utmost importance in the functional evaluation of novel peptides that the primary structure of the mature peptide is unequivocally established - something that is often facilitated by cloning biosynthetic precursor cDNAs but obviously not reliable using such data alone. (C) 2008 Elsevier Masson SAS. All rights reserved.

Narrow bandwidth red electroluminescence from solution-processed lanthanide-doped polymer thin films

Narrow bandwidth red electroluminescence from OLED devices fabricated using a simple solution-based approach is demonstrated. A spin-casting method is employed to fabricate organic light emitting diode (OLED) devices comprising a poly(N-vinylcarbazole) (PVK) host matrix doped with a europium beta-diketonate complex, Eu(dbM)(3)(Phen) (dibenzoylmethanate, dbm; 1,10-phenanthroline, Phen) on glass/ indium tin oxide (ITO)/3,4-polyethylene-dioxythiophene-polystyrene sulfonate (PEDOT) substrates. Saturated red europium ion emission, based on the (5)Do ->F-7(2) transition, is centered at a wavelength of 612 nm with a full width at half maximum of 3.5 rim. A maximum external quantum efficiency of 6.3 x 10(-2) cd/A (3.1 X 10(-2)%) and a maximum luminance of 130 cd/M-2 at 400 mA/cm(2) and 25 V is measured for ITO/PEDOT/PVK:Eu(dbM)3(Phen)/Ca/Al devices. This measured output luminance is comparable to that of devices fabricated using more sophisticated small molecule evaporation techniques. (c) 2005 Elsevier B.V All rights reserved.

“Hegemony Protected by the Armour of Coercion”: Dashiell Hammett’s Red Harvest and the State

This article argues that Dashiell Hammett's 1929 novel Red Harvest is best understood in the context of the consolidation and expansion of the US state following the First World War and the Russian Revolution. It also argues that Hammett's novel constitutes a highly significant articulation of theoretical debates about the nature of political authority and state power in the modern era and speaks about the transition of one state formation to another. Insofar as Red Harvest explores the way in which the state's coercive and ethical character are bound up together, this article argues that Hammett's novel draws upon an understanding of political authority and state power primarily derived from Gramsci, via Marx. Gramsci insists that control cannot be maintained through force alone (and his conception of hegemony, in turn, suggests a power bloc that can become fragmented and disunited in a war of position). In the same way, Red Harvest traces the transformation of the “economic-corporate” state into the expanded or “ethical” State but crucially any ethical dimension, as Gramsci notes, is always beholden to the needs of the capitalist economy. As such, the apparently arbitrary bloodshed in the novel is conceived as a relatively minor realignment in the ranks of the capitalist classes – certainly less serious than the miners' strike that prefigures the novel. What makes this realignment significant is that it calls attention to the state both as repressive and as a site of conflict and compromise. Here, the work performed by the Continental Op and by the crime novel in general – simultaneously buttressing and, to some extent, contesting the power of the state – needs to be understood as part of the process by which the state is consistently enacting hegemony (albeit protected by the armour of coercion). The article concludes by pointing out that while Gramsci is perhaps too willing to dwell upon the state's expanded reach, Red Harvest is more interested in examining possible “cracks and fissures” in the state formation, even if the critique it ultimately offers goes nowhere and yields nothing.

Red meat consumption: An overview of the risks and benefits

Red meat is long established as an important dietary source of protein and essential nutrients including iron, zinc and vitamin B12, yet recent reports that its consumption may increase the risk of cardiovascular disease (CVD) and colon cancer have led to a negative perception of the role of red meat in health. The aim of this paper is to review existing literature for both the risks and benefits of red meat consumption, focusing on case-control and prospective studies. Despite many studies reporting an association between red meat and the risk of CVD and colon cancer, several methodological limitations and inconsistencies were identified which may impact on the validity of their findings. Overall, there is no strong evidence to support the recent conclusion from the World Cancer Research Fund (WCRF) report that red meat has a convincing role to play in colon cancer. A substantial amount of evidence supports the role of lean red meat as a positive moderator of lipid profiles with recent Studies identifying it as a dietary source of the anti-inflammatory long chain (LC) n-3 PUFAs and conjugated linoleic acid (CIA). In conclusion. moderate consumption of lean red meat as part of a balanced diet is unlikely to increase risk for CVD or colon cancer, but may positively influence nutrient intakes and fatty acid profiles, thereby impacting positively on long-term health. (C) 2009 Elsevier Ltd. All rights reserved

Red meat from animals offered a grass diet increases plasma and platelet n-3 PUFA in healthy consumers

Red meat from grass-fed animals, compared with concentrate-fed animals, contains increased concentrations of long-chain (LC) n-3 PUPA. However, the effects of red meat consumption from grass-fed animals on consumer blood concentrations of LC n-3 PUFA are unknown. The aim of the present study was to compare the effects on plasma and platelet LC n-3 PUFA status of consuming red meat produced from either grass-fed animals or concentrate-fed animals. A randomised, double-blinded, dietary intervention study was carried out for 4 weeks on healthy subjects who replaced their habitual red meat intake with three portions per week of red meat (beef and lamb) from animals offered a finishing diet of either grass or concentrate (n 20 consumers). Plasma and platelet fatty acid composition, dietary intake, blood pressure, and serum lipids and lipoproteins were analysed at baseline and post-intervention. Dietary intakes of total n-3 PUFA, as well as plasma and platelet concentrations of LC n-3 PUFA, were significantly higher in those subjects who consumed red meat from grass-fed animals compared with those who consumed red meat from concentrate-fed animals (P<0.05). No significant differences in concentrations of serum cholesterol, TAG or blood pressure were observed between groups. Consuming red meat from grass-fed animals compared with concentrate-fed animals as part of the habitual diet can significantly increase consumer plasma and platelet LC n-3 PUFA status. As a result, red meat from grass-fed animals may contribute to dietary intakes of LC n-3 PUFA in populations where red meat is habitually consumed.

List 229: Irish and English Dendrochronology

These results cover dating undertaken since the last published list of dated building from Ireland (Brown (2002)); one English church building is also included in the list. Thanks are due to the owners of the buildings and especially to everyone who assisted in taking of the samples: Phil Barrett, Sapphire Mussen, Charles Lyons, Jon Pilcher and Mike Baillie, Amanda Pedlow, Caimin O’Brien and Martin Timoney. Most of the descriptions of the buildings are taken from the National Inventory of Architectural Heritage http://www.buildingofi reland.ie/. The correlation values were generated by CROSS84 (Munro, 1984), which provides a signifi cance level for the date to be correct; *** (extremely signifi cant), ** (very signifi cant), * (signifi cant), nsm (not signifi cant). Estimated felling date ranges are based on the Belfast sapwood estimate of 32 ± 9 years. Date ranges have been calculated by adding and subtracting 9 years from the calculated estimated felling dates. Timbers from the following buildings could not be dated. Cork: St Finbarre’s Cathedral (W 675 715); Dublin: Christchurch Cathedral (O 152 341); Galway: Cloghan Castle (M 972 119); Kilkenny: Rothe House (S 506 563); Offaly: Boveen House (S 075 956); Waterford: Christchurch Cathedral (S 616 121). Generally only single oak samples were recovered from these structures. References: D.Brown, ‘Dendrochronological dating building from Ireland’, VA 33 (2002), 71–3; M. Munro, ‘An improved algorithm for crossdating tree-ring series’, Tree-Ring Bulletin 44 (1984), 17–27.