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921.
922.
Subtil-Rodríguez A Millán-Ariño L Quiles I Ballaré C Beato M Jordan A 《Molecular and cellular biology》2008,28(11):3830-3849
923.
Muñoz FJ Rumbero A Sinisterra JV Santos JI André S Gabius HJ Jiménez-Barbero J Hernáiz MJ 《Glycoconjugate journal》2008,25(7):633-646
The emerging role of glycans as versatile biochemical signals in diverse aspects of cellular sociology calls for establishment
of sensitive methods to monitor carbohydrate recognition by receptors such as lectins. Most of these techniques involve the
immobilization of one of the binding partners on a surface, e.g. atomic force microscopy, glycan array and Surface Plasmon Resonance (SPR), hereby simulating cell surface presentation.
Here, we report the synthesis of fluorescent glycoconjugates, with a functionalization strategy which avoids the frequently
occurring ring opening at the reducing end for further immobilization on a surface or derivatization with biotin. In order
to improve the versatility of these derivatized glycans for biological studies, a new approach for the synthesis of biotinylated
and fluorescent glycans has also been realized. Finally, to illustrate their usefulness the neoglycoconjugates were immobilized
on different surfaces, and the interaction analysis with a model lectin, the toxin from mistletoe, proved them to act as potent
ligands, underscoring the merit of the presented synthetic approach.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
924.
Carme Gubern Olivia Hurtado Rocío Rodríguez Jesús R Morales Víctor G Romera María A Moro Ignacio Lizasoain Joaquín Serena Judith Mallolas 《BMC molecular biology》2009,10(1):57
Background
Studies of gene expression in experimental cerebral ischaemia models can contribute to understanding the pathophysiology of brain ischaemia and to identifying prognostic markers and potential therapeutic targets. The normalization of relative qRT-PCR data using a suitable reference gene is a crucial prerequisite for obtaining reliable conclusions. No validated housekeeping genes have been reported for the relative quantification of the mRNA expression profile activated in in-vitro ischaemic conditions, whereas for the in-vivo model different reference genes have been used. 相似文献925.
Javier Espino Matías Mediero Graciela M Lozano Ignacio Bejarano Águeda Ortiz Juan F García José A Pariente Ana B Rodríguez 《Reproductive biology and endocrinology : RB&E》2009,7(1):11-11
Background
Asthenozoospermia is one of the most common findings present in infertile males characterized by reduced or absent sperm motility, but its aetiology remains unknown in most cases. In addition, calcium is one of the most important ions regulating sperm motility. In this study we have investigated the progesterone-evoked intracellular calcium signal in ejaculated spermatozoa from men with normospermia or asthenozoospermia. 相似文献926.
Bente Foereid Lorna A. Dawson David Johnson J. Ignacio Rangel-Castro 《Plant and Soil》2006,287(1-2):301-311
Knowledge of the fate of plant assimilate is fundamental to our understanding of the terrestrial carbon cycle, particularly if we are to predict the effects of changes in climate and land management practices on agroecosystems. Pulse-labelling experiments have revealed that some of the carbon fixed by plants is rapidly allocated below-ground and released back into the atmosphere in respiration. However, little is known about the fate of plant assimilate, not accounted for in soil respiration, in the longer term and how current management practices such as liming may affect this. In southern Scotland, UK, limed and unlimed acid grassland plots were pulse-labelled with 13CO2 and the turnover of 13C was studied one and two years after labelling. In this study the amount of labelled carbon remaining in shoot, root, and bulk soil pools, and how this differed between limed and unlimed plots was investigated. The results indicated that plant-root turnover was faster, and plants invested less nitrogen in the roots in the limed plots than in the unlimed plots. More 13C remained in the soil in the unlimed treatment compared to the limed treatment, but the main difference was found in the particulate organic matter, which turned over relatively quickly. The label was still above natural abundance one and two years after labelling in many cases. In addition, the results demonstrate that a 13CO2 pulse-label administered for only a few hours can be a useful approach for investigating turnover of carbon several years later. 相似文献
927.
928.
Cunha C Ignacio D Coelho MM 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2008,363(1505):2921-2929
Polyploidy, hybridization and variation in mating systems are central issues for a deeper understanding of animal evolution. The Iberian species Squalius alburnoides represents an example combining all three phenomena. Previous studies showed that S. alburnoides populations are mainly composed of triploid and diploid hybrid forms (mainly females), and that the tetraploid forms are rare or absent. Both populations from the Douro drainage reveal a distinct scenario: tetraploid individuals represent 85.6-97.5% of the population, with no sex ratio bias observed. Based on the flow cytometry measurements of blood and spermatozoa cells, microsatellite loci and experimental crosses, we describe here, for the first time, two symmetric allotetraploid populations (CCAA) that resumed normal meiosis after undergoing intermediate processes of non-sexual reproduction to give rise to a new sexually reproducing polyploid species. Prezygotic (habitat selection and assortative mating) and postzygotic mechanisms (nonviable embryos) are responsible for the reproductive isolation from other forms of the S. alburnoides complex (e.g. CA, CAA). This example illustrates how hybrid polyploid complexes may lead to speciation. 相似文献
929.
Hernández JC León F Brouard I Torres F Rubio S Quintana J Estévez F Bermejo J 《Bioorganic & medicinal chemistry》2008,16(4):2063-2076
This study was carried out to assess the cytotoxicity of several new synthetic steroidal saponins against the human myeloid leukemia cell lines (HL-60 and U937) and against human melanoma cells (SK-MEL-1). Several diosgenyl glycosides analyzed showed strong cell growth inhibition which was associated with alterations in cell cycle progression and induction of apoptosis. Studies of cytochrome c release and caspase-9 activation suggest a main role of the intrinsic pathway of apoptosis in the mechanism of cytotoxicity caused by this kind of compounds. 相似文献
930.