Regulation of the alpha-fetoprotein promoter: Ku binding and DNA spatial conformation

This work shows that the proximal promoter of the mouse Afp gene contains a Ku binding site and that Ku binding is associated with down-regulation of the transcriptional activity of the Afp promoter. The Ku binding site is located in a segment able to adopt a peculiar structured form, probably a hairpin structure. Interestingly, the structured form eliminates the binding sites of the positive transcription factor HNF1. Furthermore, a DNAse hypersensitive site is detected in footprinting experiments done with extracts of AFP non-expressing hepatoma cells. These observations suggest that the structured form is stabilised by Ku and is associated with extinction of the gene in AFP non-expressing hepatic cells.

Characterization of human 3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase gene and its expression in mammalian cells

Three β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase (3β-HSD) catalyze the oxidative conversion of Δ5-3β-hydroxysteroids to the Δ4-3-keto configuration and is therefore essential for the biosynthesis of all classes of hormonal steroids, namely progesterone, glucocorticoids, mineralocorticoids, androgens, and estrogens. Using human 3β-HSD cDNA as probe, a human 3β-HSD gene was isolated from a λ-EMBL3 library of leucocyte genomic DNA. A fragment of 3β-HSD genomic DNA was also obtained by amplification of genomic DNA using the polymerase chain reaction. The 3β-HSD gene contains a 5′-untranslated exon of 53 base pairs (bp) and three successive translated exons of 232, 165, and 1218 bp, respectively, separated by introns of 129, 3883, and 2162 bp. The transcription start site is situated 267 nucleotides upstream from the ATG initiating codon. DNA sequence analysis of the 5′-flanking region reveals the existence of a putative TATA box (ATAAA) situated 28 nucleotides upstream from the transcription start site while a putative CAAT binding sequence is located 57 nucleotides upstream from the TATA box. Expression of a cDNA insert containing the coding region of 3β-HSD in nonsteroidogenic cells shows that the gene encodes a single 42-kDa protein containing both 3β-hydroxysteroid dehydrogenase and Δ5-Δ4-isomerase activities. Moreover, all natural steroid substrates tested are transformed with comparable efficiency by the enzyme. In addition to its importance for studies of the regulation of expression of 3β-HSD in gonadal as well as peripheral tissues, knowledge of the structure of the human 3β-HSD gene should permit investigation of the molecular defects responsible for 3β-HSD deficiency, the second most common cause of adrenal hyperplasia in children.

Science objectives and performances of NOMAD, a spectrometer suite for the ExoMars TGO mission

The NOMAD spectrometer suite on the ExoMars Trace Gas Orbiter will map the composition and distribution of Mars atmospheric trace species in unprecedented detail, fulfilling many of the scientific objectives of the joint ESA-Roscosmos ExoMars Trace Gas Orbiter mission. The instrument is a combination of three channels, covering a spectral range from the UV to the IR, and can perform solar occultation, nadir and limb observations. In this paper, we present the science objectives of the instrument and how these objectives have influenced the design of the channels. We also discuss the expected performance of the instrument in terms of coverage and detection sensitivity.

The HITRAN molecular spectroscopic database: Edition of 2000 including updates through 2001

This paper describes the status circa 2001, of the HITRAN compilation that comprises the public edition available through 2001. The HITRAN compilation consists of several components useful for radiative transfer calculation codes: high-resolution spectroscopic parameters of molecules in the gas phase, absorption cross-sections for molecules with very dense spectral features, aerosol refractive indices, ultraviolet line-by-line parameters and absorption cross-sections, and associated database management software. The line-by-line portion of the database contains spectroscopic parameters for 38 molecules and their isotopologues and isotopomers suitable for calculating atmospheric transmission and radiance properties. Many more molecular species are presented in the infrared cross-section data than in the previous edition, especially the chlorofluorocarbons and their replacement gases. There is now sufficient representation so that quasi-quantitative simulations can be obtained with the standard radiance codes. In addition to the description and justification of new or modified data that have been incorporated since the last edition of HITRAN (1996), future modifications are indicated for cases considered to have a significant impact on remote-sensing experiments. © 2003 Elsevier Ltd. All rights reserved.

Laboratory Fourier transform spectroscopy of the water absorption continuum from 2500 to 22500 cm-1

info:eu-repo/semantics/published

Synthesis of cycloruthenated compounds as potential anticancer agents

A library of 19 cycloruthenated derivatives is constructed by making use of the well-known cyclometalation reaction. Their geometries are modified in a straightforward manner by addition of either mono- or bidentate ligands, such as bipyridine, phenanthroline, 1,2-bis(diphenylphosphanyl)ethane, dimethylphenylphosphane, triphenylphosphane, and 1,3,5-triaza-7-phosphatricyclo[3.3.1.1]decane (PTA) ligands, to cationic cycloruthenated centers. The antitumor properties of the compounds thus obtained are investigated in order to compare them with recently reported ruthenium complexes and cisplatin. IC50 values against mammalian cells (A-172, HCT-116, and RDM-4) are determined for the library compounds and some of them, such as those derived from orthoruthenated phenylpyridine and a bidentate N,N ligand, display activity of the same order of magnitude as cisplatin.

Contributions to the bryological flora of the tropical and subtropical forests from the Argentina (Bryophyta, Musci).

The authors present here a list of 32 mosses belonging to 15 families: Brachytheciaceae, Cryphaeaceae, Entodontaceae, Hedwigiaceae, Hypnaceae, Leptodontaceae, Meteoriaceae, Neckeraceae, Pilotrichaceae, Polytrichaceae, Pterobryaceae, Racopilaceae, Rigodiaceae, Stereophyllaceae, and Trachypodaceae, all collected in the mountainous forests of the Yungas of the NW of the Argentina (Jujuy, Salta, Catamarca and Tucumán provinces), and also in the rainforests from the NE of the country (Misiones province). Eight species: Atrichum polycarpum, Chrysohypnum elegantulum, Pilosium chlorophyllum, Pilotrichella flexilis, Porotrichodendron lindigii, Pseudotrachypus martinicensis, Steerecleus scariosus, and Thamnobryum fasciculatum are new records for the bryologic flora from Argentina. Braunia imberbis and Squamidium brasiliense are two new records for the bryophytic flora of the Catamarca province; Porotrichodendron superbum is new for the Salta province, while Forsstroemia coronata is the first record for the Catamarca and Jujuy provinces. Aerolindigia capillacea, Braunia reflexifolia, Chryso-hypnum diminutivum, Meteorium deppei and Meteoridium remotifolium are five new citations for the Jujuy province, and Schoenobryum concavifolium is new for the bryophytic flora of the Misiones province. Many studied species occur more frequently in the Yungas than in the NE rainforests; others show separated distribution but live in both areas, the Yungas and Paranaense area, and others are more or less restricted to the Paranaense rainforest of the NE of Argentina. The taxonomy of species is updated, and comments are included on bibliographical precedents, ecology and chorology of each taxon.

Biomonitoring of air pollutants by using lichens (Evernia prunastri) in areas between Kenitra and Mohammedia cities in Morocco.

In this study, Evernia prunastri, a lichen growing in its natural habitat in Morocco was analysed for the concentration of five heavy metals (Fe, Pb, Zn, Cu and Cr) from eleven sites between Kenitra and Mohammedia cities. The control site was Dar Essalam, an isolated area with low traffic density and dense vegetation. In the investigated areas, the concentration of heavy metals was correlated with vehicular traffic, industrial activity and urbanization. The total metal concentration was highest in Sidi Yahya, followed by Mohammedia and Bouznika. The coefficient of variation was higher for Pb and lower for Cu, Zn and Fe. The concentrations of most heavy metals in the thalli differed significantly between sites (p<0.01). Principal component analysis (PCA) revealed a significant correlation between heavy metal accumulation and atmospheric purity index. This study demonstrated also that the factors most strongly affecting the lichen flora were traffic density, the petroleum industry and paper factories in these areas. Overall, these results suggest that the index of atmospheric purity and assessment of heavy metals in lichen thalli are good indicators of the air quality at the studied sites.

Nomenclature and syntaxonomic notes on some high-rank syntaxa of the European grassland vegetation

We present descriptions of a new order (Ranunculo cortusifolii-Geranietalia reuteri and of a new alliance (Stachyo lusitanicae-Cheirolophion sempervirentis) for the herbaceous fringe communities of Macaronesia and of the southwestern Iberian Peninsula, respectively. A new alliance, the Polygalo mediterraneae-Bromion erecti (mesophilous post-cultural grasslands), was introduced for the Peninsular Italy. We further validate and typify the Armerietalia rumelicae (perennial grasslands supported by nutrient-poor on siliceous bedrocks at altitudes characterized by the submediterranean climate of central-southern Balkan Peninsula), the Securigero-Dasypyrion villosae (lawn and fallow-land tall-grass annual vegetation of Italy), and the Cirsio vallis-demoni-Nardion (acidophilous grasslands on siliceous substrates of the Southern Italy). Nomenclatural issues (validity, legitimacy, synonymy, formal corrections) have been discussed and clarified for the following names: Brachypodio-Brometalia, Bromo pannonici-Festucion csikhegyensis, Corynephoro-Plantaginion radicatae, Heleochloion, Hieracio-Plantaginion radicatae, Nardetea strictae, Nardetalia strictae, Nardo-Callunetea, Nardo-Galion saxatilis, Oligo-Bromion, Paspalo-Heleochloetalia, Plantagini-Corynephorion and Scorzoneret alia villosae. 

Validations and descriptions of European syntaxa of vegetation dominated by lichens, bryophytes and algae

Fourty-two high-rank syntaxa and seven associations of the thallophyte system of syntaxa are either described as new or validated in this paper. Among those, there are the following nine classes: Aspicilietea candidae, Caulerpetea racemosae, Desmococcetea olivacei, Entophysalidetea deustae, Gloeocapsetea sanguineae, Mesotaenietea berggrenii, Naviculetea gregariae, Porpidietea zeoroidis, Roccelletea phycopsis. Eleven orders and ten alliances as well as three associations are described or validated: the Aspicilietalia verruculosae (incl. Aspicilion mashiginensis and Teloschistion contortuplicati), the Caulerpetalia racemosae (incl. Caulerpion racemosae), the Desmococcetalia olivacei (incl. Desmococcion olivacei), the Dirinetalia massiliensis, the Fucetalia vesiculosi (incl. Ascophyllion nodosi), the Gloeocapsetalia sanguineae, the Lecideetalia confluescentis (incl. Lecideion confluescentis), the Mesotaenietalia berggrenii (incl. Mesotaenion berggrenii, Mesotaenietum berggrenii and Chloromonadetum nivalis), the Naviculetalia gregariae (incl. Oscillatorion limosae and Oscillatorietum limosae), the Porpidietalia zeoroidis (incl. Porpidion zeoroidis), and the Roccelletalia fuciformis (incl. Paralecanographion grumulosae). Further, five orders, seven alliances and four associations, classified in known classes, were described as well. These include: the Bacidinetalia phacodis, the Agonimion octosporae and the Dendrographetalia decolorantis (all in the Arthonio radiatae-Lecidelletea elaeochromae), the Staurothelion solventis (in the Aspicilietea lacustris), the Pediastro duplicis-Scenedesmion quadricaudae and the Pediastro duplicis-Scenedesmetum quadricaudae (both in the Asterionelletea formosae), the Peccanion coralloidis and the Peltuletalia euplocae (both in the Collematetea cristati), the Laminarion hyperboreae, the Saccorhizo polyschidi-Laminarietum and the Alario esculenti-Himanthalietum elongatae (all in the Cystoseiretea crinitae), the Delesserietalia sanguinei, the Delesserion sanguinei and the Delesserietum sanguineae (all in the Lithophylletea soluti), as well as the the Rinodino confragosae-Rusavskietalia elegantis and the Rhizocarpo geographici-Rusavskion elegantis (both in the Rhizocarpetea geographici).

Aplicación de modelos semióticos al análisis de poesía narrativa popular ecuatoriana difundida en audiovisuales

Se expone una fundamentación teórica, lógica y metodológica de tres modelos semióticos: los elementos y funciones de la comunicación de Jakobson; el modelo actancial de Greimas; y los mundos: real, referencia y posible de Eco, aplicados al análisis de poesía narrativa popular difundida en distintos formatos audiovisuales.

Una revisión de la Cadena Datos-Información-Conocimiento desde el Pragmatismo de Peirce

La Cadena Datos-Información-Conocimiento (DIC), denominada “Jerarquía de la Información” o “Pirámide del Conocimiento”, es uno de los modelos más importantes en la Gestión de la Información y la Gestión del Conocimiento. Por lo general, la estructuración de la cadena se ha ido definiendo como una arquitectura en la que cada elemento se levanta sobre el elemento inmediatamente inferior; sin embargo no existe un consenso en la definición de los elementos, ni acerca de los procesos que transforman un elemento de un nivel a uno del siguiente nivel. En este artículo se realiza una revisión de la Cadena Datos-Información-Conocimiento examinando las definiciones más relevantes sobre sus elementos y sobre su articulación en la literatura, para sintetizar las acepciones más comunes. Se analizan los elementos de la Cadena DIC desde la semiótica de Peirce; enfoque que nos permite aclarar los significados e identificar las diferencias, las relaciones y los roles que desempeñan en la cadena desde el punto de vista del pragmatismo. Finalmente se propone una definición de la Cadena DIC apoyada en las categorías triádicas de signos y la semiosis ilimitada de Peirce, los niveles de sistemas de signos de Stamper y las metáforas de Zeleny.

El apoyo a la investigación en las bibliotecas universitarias españolas

Los cambios sufridos por los modelos de comunicación científica hacen que las bibliotecas universitarias se vean obligadas a dar nuevos servicios. Para adecuarse al investigador los bibliotecarios están desarrollando habilidades, colaborando con cada vez más estamentos y sustentando el acceso abierto. Apoyándose en una lista de posibles servicios, basada en la literatura especializada, este trabajo pretende cuantificar y evaluar el apoyo a la investigación desde las bibliotecas universitarias españolas. El sondeo demuestra la aparición de nuevos servicios e infraestructuras. Pero estas asistencias no suelen sistematizarse, difundirse ni evaluarse. Y, por otra parte, las consecuentes inversiones en personal y TIC han generado una brecha entre universidades