477 research outputs found
Los telómeros y el origen de la enfermedad
Este artículo recoge la presentación que la autora llevó a cabo de su carrera científica en el Foro de Encuentros, en Madrid, en Febrero de 2016En el presente texto se recoge la descripción de la trayectoria científica de María A. Blasco, Directora del Centro Nacional de Investigaciones Oncológicas e investigadora española de prestigio internacional, contada por la propia autora, a través de un conjunto de breves apuntes o hitos que han ido jalonando esa carrera científica, enormemente prolífica y cargada de interés científico y social, la cual comenzó después de finalizar su licenciatura en Ciencias Biológicas en la Universidad Autónoma de Madrid, en cuyo Centro de Biología Molecular inició su andadura científica de la mano de Margarita Salas, prestigiosa científica de reconocimiento mundial y a quien entrevistó Encuentros Multidisciplinares en el año 2000, entrevista publicada en el Vol. II nº 1 de esta revista. Aparte de la importancia de su contenido, publicamos este texto como un ejemplo que puede servir como referencia para jóvenes investigadores o universitarios que están planteándose iniciar una carrera investigador
Generation of mice with longer and better preserved telomeres in the absence of genetic manipulations.
Although telomere length is genetically determined, mouse embryonic stem (ES) cells with telomeres of twice the normal size have been generated. Here, we use such ES cells with ‘hyper-long’ telomeres, which also express green fluorescent protein (GFP), to generate chimaeric mice containing cells with both hyper-long and normal telomeres. We show that chimaeric mice contain GFP-positive cells in all mouse tissues, display normal tissue histology and normal survival. Both hyper-long and normal telomeres shorten with age, but GFP-positive cells retain longer telomeres as mice age. Chimaeric mice with hyper-long telomeres also accumulate fewer cells with short telomeres and less DNA damage with age, and express lower levels of p53. In highly renewing compartments, such as the blood, cells with hyper-long telomeres are longitudinally maintained or enriched with age. We further show that wound-healing rates in the skin are increased in chimaeric mice. Our work demonstrates that mice with functional, longer and better preserved telomeres can be generated without the need for genetic manipulations, such as TERT overexpression.post-print3240 K
Data Sources as a Driver for Market‑Oriented Tourism Organizations: a Bibliometric Perspective
This paper presents a conceptual framework that accurately represents the current
and future perspectives of data-driven companies in tourism by means of an analysis
of the data sources used in the data-driven tourism research literature, as well as the
research topics to which they are applied. For this purpose, a bibliometric analysis
of data-driven tourism research is carried out. The framework of the study is all
tourism-related publications whose research was based on data sources during the
period 1982–2020. The results show some of the basic bibliometric performance
indicators and the maps of science. The main themes of research interest are identified,
and the conceptual evolution is obtained based on these maps. Three major
thematic areas are identified: tourism research topics, information sources, and data
analysis techniques. Based on these three thematic areas, the conceptual model of
data architecture and processes of a data-driven organization in the tourism sector
are obtained. An additional qualitative analysis of the three thematic areas is
performedCRUE-CSIC agreement with Springer Natur
Suv4-20h deficiency results in telomere elongation and derepression of telomere recombination
Mammalian telomeres have heterochromatic features, including trimethylated histone H3 at lysine 9 (H3K9me3) and trimethylated histone H4 at lysine 20 (H4K20me3). In addition, subtelomeric DNA is hypermethylated. The enzymatic activities responsible for these modifications at telomeres are beginning to be characterized. In particular, H4K20me3 at telomeres could be catalyzed by the novel Suv4-20h1 and Suv4-20h2 histone methyltransferases (HMTases). In this study, we demonstrate that the Suv4-20h enzymes are responsible for this histone modification at telomeres. Cells deficient for Suv4-20h2 or for both Suv4-20h1 and Suv4-20h2 show decreased levels of H4K20me3 at telomeres and subtelomeres in the absence of changes in H3K9me3. These epigenetic alterations are accompanied by telomere elongation, indicating a role for Suv4-20h HMTases in telomere length control. Finally, cells lacking either the Suv4-20h or Suv39h HMTases show increased frequencies of telomere recombination in the absence of changes in subtelomeric DNA methylation. These results demonstrate the importance of chromatin architecture in the maintenance of telomere length homeostasis and reveal a novel role for histone lysine methylation in controlling telomere recombination
Effect of potential formation on the electrochemical behaviour of a highly-alloyed austenitic stainless steel in contaminated phosphoric acid at different temperatures
The electrochemical behaviour of the highly alloyed austenitic stainless steel UNS N08031 (Alloy 31) in a contaminated phosphoric acid solution is studied using potentiodynamic curves, EIS and Mott–Shottky. The relative stability of the films formed on Alloy 31 has been studied after a pre-passivated treatment at 0.3, 0.5, 0.8 and 1 VAg/AgCl, potentials within the passive domain. The protection of Alloy 31 was provided by the inner oxide film, while the outer film was more defective. The electronic-semiconducting properties of the passive films have been correlated to corrosion resistance. Passivated Alloy 31 at 0.8 VAg/AgCl showed lower concentration of charge carriers, which beneficially affects the protecting and electronic properties of the passive oxide film.The authors wish to express their gratitude to the MAEC of Spain (PCI Mediterraneo C/8196/07, C/018046/08, D/023608/09 and D/030177/10), to Programa de Apoyo a la Investigacion y Desarrollo de la UPV (PAID-06-09), to the Generalitat Valenciana (GV/2011/093) for the financial support and to Dra. Asuncion Jaime for her translation assistance.Escrivá Cerdán, C.; Blasco Tamarit, ME.; García García, DM.; García Antón, J.; Guenbour, A. (2012). Effect of potential formation on the electrochemical behaviour of a highly-alloyed austenitic stainless steel in contaminated phosphoric acid at different temperatures. Electrochimica Acta. 80:248-256. https://doi.org/10.1016/j.electacta.2012.07.012S2482568
Relationship Between the Quorum Network (Sensing/Quenching) and Clinical Features of Pneumonia and Bacteraemia Caused by A. baumannii
Acinetobacter baumannii (Ab) is one of the most important pathogens associated
with nosocomial infections, especially pneumonia. Interest in the Quorum network,
i.e., Quorum Sensing (QS)/Quorum Quenching (QQ), in this pathogen has grown
in recent years. The Quorum network plays an important role in regulating diverse
virulence factors such as surface motility and bacterial competition through the
type VI secretion system (T6SS), which is associated with bacterial invasiveness.
In the present study, we investigated 30 clinical strains of A. baumannii isolated in
the “II Spanish Study of A. baumannii GEIH-REIPI 2000-2010” (Genbank Umbrella
Bioproject PRJNA422585), a multicentre study describing the relationship between the
Quorum network in A. baumannii and the development of pneumonia and associated
bacteraemia. Expression of the aidA gene (encoding the AidA protein, QQ enzyme) was
lower (P < 0.001) in strains of A. baumannii isolated from patients with bacteraemic
pneumonia than in strains isolated from patients with non-bacteraemic pneumonia.
Moreover, aidA expression in the first type of strain was not regulated in the presence
of environmental stress factors such as the 3-oxo-C12-HSL molecule (substrate of AidA
protein, QQ activation) or H2O2 (inhibitor of AidA protein, QS activation). However, in the
A. baumannii strains isolated from patients with non-bacteraemic pneumonia, aidA gene
expression was regulated by stressors such as 3-oxo-C12-HSL and H2O2. In an in vivo
Galleria mellonella model of A. baumannii infection, the A. baumannii ATCC 17978 strain
was associated with higher mortality (100% at 24 h) than the mutant, abaI-deficient, strain (carrying a synthetase enzyme of Acyl homoserine lactone molecules) (70% at 24 h).
These data suggest that the QS (abaR and abaI genes)/QQ (aidA gene) network affects
the development of secondary bacteraemia in pneumonia patients and also the virulence
of A. baumannii.National Plan for Scientific ResearchTechnological Development and Innovation PI16/01163ISCIII-Deputy General Directorate for Evaluation and Promotion of Research-European Regional Development Fund A way of Making EuropeInstituto de Salud Carlos IIIMiguel Servet Research Programme SERGAS and ISCIIIXunta de Galicia (GAIN, Axencia de Innovación
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